BACKGROUND OF THE INVENTION
Field of the Invention
This invention relates to a gases supply and gases humidification apparatus, particularly
but not solelv for providing respiratory assistance to patients or users who require a supply of
humidified gas at positive pressure for the treatment of diseases such as Obstructive Sleep Apnea
(OSA), snoring, or Chronic Obstructive Pulmonary Disease (COPD) and the like. In particular,
this invention relates to a gases supply apparatus which has an integral humidifier chamber, so as
to form a combined assisted breathing unit and humidifier.
Summary of the Prior Art
Devices or systems for providing a humidified gases flow to a patient for therapeutic
purposes are well known in the art. Systems for providing therapy of this type, for example
CPAP therapy, have a structure where gases at the required pressure are delivered from an
assisted breathing unit or blower unit to a humidifier chamber downstream from the blower. As
the gases are passed through the heated, humidified air in the humidifier chamber, they become
saturated with water vapour. The gases arc then delivered to a user or padent downstream from
the humidifier, via a gases conduit. Humidified gases can be delivered from a modular system
that has been assembled from separate units (that is, a system where the humidifier
chamber/heater and the breathing unit/blower are separate items) connected in series via
conduits. An example of a system of this type is shown in Figure 1. However, it is becoming
more common for integrated blower/humidifier systems to be used, as shown schematically in
Figure 2. A typical integrated system consists of a mam 'blower' or assisted breathing unit which
provides a pressurised gases flow, and a humidifier unit that mares with or is otherwise rigidly
connected to the blower unit. This mating occurs for example by a slide on or push connection,
so that the humidifier is held firmly in place on the main blower unit. An example of a system of
this type is the Fisher and Paykel Healthcare 'slide-on' water chamber system shown and
described in US 7,111,624. A variation of this design is a slide-on or clip-on design where the
chamber is enclosed inside a portion of the integrated unit in use. An example of this type of
design is shown in WO 2004/112873. This specification describes a blower, or flow generator 50,
and an associated humidifier 150. The blower unit 50 and the humidifier unit 150 arc brought
together in use and connected as described in paragraph 00119 of tins document. The humidifier
chamber, or water tub (698, 699, 700) is described in paragraphs 00132 to 00141. It should be
noted that the water tub can either be filled through the passage 722 (described in detail in
paragraph 00126), which is located on the rear wall of the humidifier unit 150, or by removing the

tub lid 700. The process for removing the lid is described in paragraph 00136. When the lid of
the humidifier unit (lid 648) is closed, this pushes the water tub into position.
WO 04/112873 also describes a power supply cavity, shown as item 65 in Figure 6, and
described in paragraphs [0096] and [0097]. The compartment is described as being vented to
atmosphere (if necessary) for cooling. Figure 7 shows the power supply board 124 and the cavity
65. As described in paragraph [00100], air enters the blower through an air inlet 84,
communicating with passage 85 above the power supply cavity 65, with the passage then leading
to the muffler cavity 134 in which the fan unit 90 sits. It should be noted that as shown in figure
6, the power supply cavity 65 is insulated from the air supply passage 85 and the muffler cavity
134 by two walls, with an airgap between them. Using this air flow to cool the power supply
board is not discussed in this specification.
A further example of this type of design is shown in US 7,096,864. The humidifier
chamber 17 is partly enclosed in a humidifier unit 16, which is push-fitted to a separate blower or
CPAP unit 1.
In the devices shown in WO 2004/112873 and US 7,096,864, the blower unit and the
humidifier unit are both discrete, 'table-standing' units, pushed together to mate pneumatically
and electrically.
A further variation of the integrated blower and humidifier type of design is shown in US
6,435,180. A water container or humidifier chamber 66 has a lid 72. The lid 72 of the humidifier
chamber 66 is located in use underneath a cover 94 that covers the entire top part of the unit.
Cover 94 and lid 72 can be removed simultaneously by a user passing their fingers and thumbs
through the holes 92. Two separate air streams (a humidified stream and a dry stream) are mixed
in the housing of the device to create one air stream that is provided to a user (Column 6, lines
23-34). It is not intended that any of the elements such as the lids or the chamber are connected
together with fasteners or similar, so that the unit can be disassembled easily (column 6, lines 46-
55).
A hunudifier chamber with a lid is described in US 5,588,423. Lid 11 closes the top of the
chamber 2.
The advantage of these types of integrated devices is that generally they are more compact
and discrete than a modular breathing circuit that 'has been assembled from separate units. A
compact and discrete unit is particularly advantageous for home use units, where bedside space is
limited, and where a user may also have to transport and set up their own personal unit elsewhere,

for example if staying overnight away from home. With compact and integrated units, the set up
is generally easier for a user. Generally, home units are used for the relief of sleep apnoea. A '
mid-use point will usually be during the night, during a users sleep cycle. If refilling or similar is
required during use, a user will need to wake up to perform this operation. Having been woken
up, the user is required to remove the humidifier chamber from the integrated unit, refill it, then
return it into position and if necessary reassemble the unit. Humidifier chambers are often sealed
units, and cannot be easily opened. That is, they are sealed except for the inlet and outlet ports.
Chambers of this type are tilled through either the inlet or the outlet port of the chamber. This
refilling operation can be time-consuming,-difficult to perform at bedside, and can require a level
of concentration that a user may find difficult to muster in the middle of the night. It is especially
important to minimise disruption to a users sleep pattern if they suffer from sleep apnoea, as the
intent of the therapy is to minimise disruption to their sleep patterns, and any additional factors
that might disturb them are therefore unwelcome. Although chambers with lids are known in the
art as described above, these are generally not designed with the intended purpose that the lid that
it can be easily removed during use, for example for refilling the chamber. Humidifier chambers
with removable lids are generally not designed in such a manner that simplifies this operation. It
is generally intended that the lid will only be removed when the unit is not in use, to access the
inner surfaces of the chamber for e.g. cleaning or similar.
Further problems can arise when filling or cleaning these units, as nearly all of the
respiratory humidification systems currendy available use water as a humidification medium, and
cleaning will almost always be carried out with a water based cleaner. Blower and humidifier units
are operated and controlled electrically, and problems can occur if the electronic parts, such as
external user controls, are not protected. If the controls are not protected, any accidental water
spillage that takes place can potentially short-circuit the controls and disrupt the operation of the
system.
Control knobs that are designed in such a manner that the opportunities for spillage to
cause damage are known in the art.
US 6,812,435 describes a control knob for an oven that is mounted on a continuous
horizontal plate, and which can be moved around on the plate. Magnetic actuators under the
plate and in the knob interact, with Hall sensors detecting the changes in the magnetic fields. A
control unit receives the signals from the Hall sensors and alters the output parameters of the
stove accordingly.

US 2005/0205395 describes a control knob arrangement where magnetic elements are embedded
in the body of a knob 2, with their magnetic fields interacting as the knob is rotated with e.g.
rotary field sensor 25 (a Hall sensor in the embodiment described). The knob sits in a recess 16 in
a panel 14, and is held in place on the panel by retaining pegs 11 that pass through an open
aperture at the bottom of the recess 16.
As outlined above, it can be difficult to concentrate and carry out complex operations in
the middle of the night (or during the middle of a users sleep sequence), or if a users sleep pattern
has been disrupted. It is therefore considered important, or at least preferred, that the blower and
humidifier controls are as simple and intuitive as possible. Also, that the number of steps
necessary to make adjustments or carry out an operation is minimised.
One of the advantages of an integrated unit is that generally they are compact and
discrete, and are particularly suited for home use as their 'footprint' - e.g. on a bedside stand or
similar — tends to be less than modular units. It is therefore particularly advantageous if the
power supply unit can be built into, or located inside, the housing or external shell of the
integrated blower/humidifier, in order to keep the 'footprint' of the unit as small as possible.
However, If the power supply pack is external - located outside the housing or shell of the
ventilator/humidifier unit, the heat can dissipate to atmosphere easily. If the power supply unit is
located inside the shell or housing, heat from the power supply unit cannot dissipate as easily.
The ventilator or 'blower' units that form part of these integrated, compact units draw a
considerable amount of power. The power packs or power plants used to provide power to the
motor or drive units usually generate a considerable amount of heat as a by-product of this power
generation. That is, the power packs and associated circuitry (for example, transformers or similar
components) become hot as a consequence of powering the operation of the
ventilator/humidifier. As the temperature of the power supply increases, it works less effectively,
and more power is drawn to compensate for the drop in efficiency, leading to a greater heat
output, and a corresponding further drop in efficiency - a negative feedback loop. It can be seen
that it is important to prevent the power supply unit from overheating, or at least from heating up
to a temperature that is over the upper limit of an optimum operating range. This can be difficult
to achieve if the power supply is enclosed in the external shell of an compact unit that is
specifically designed to be as small as possible, with internal free space minimised. This can be
especially important if the size of the power supply itself has been minimised, and the airgaps
between components have been minimised, potentially leading to further difficulties with heat
dissipation.

US 2007/0048159 discloses a blower unit that includes electronic circuitry (referred to generally as
electronics seating portion 120). An air inlet 140 is shown direcdy below this electronic circuitry.
It is not clear from the specification whether the electronic circuitry is heat-producing circuitry -
for example, power circuitry, which generally produces a considerable amount of heat, or if it is
control circuitry, which generates much less heat and does not generally require cooling. It is also
unclear from the specification how the structure between the air path and the electronic circuitry
is configured. The wall between the components and the air flow could potentially be thick
enough to insulate the electronic circuitry from any cooling effect produced by the air flow.
Users of domestic breathing assistance apparatus (such as a CPAP device) may
occasionally wish to travel and spend the night (or longer) away from home. It is normal for the
breathing assistance apparatus to be carried in some form of bag or carry case. Many users prefer
to have the option of carrying their device as hand luggage e.g. if flying, so that they are assured of
arriving at their destination with the device. This necessitates a compact carry case (as well as a
compact device). Rigid or hard carry cases are known, which allow the user a convenient safe
method to travel with their device. One of the problems with any type of cany case is that when
the device is placed inside is the user forgetting to empty the water from the humidification
chamber. Spillages of water from the chamber can occur if the unit is packed and carried without
the contents of the chamber being emptied.
It is an object of the present invention to provide a breathing assistance apparatus which
goes some way to overcoming the abovementioned disadvantages or which at least provides the
public or industry with a useful choice.
DISCLOSURE OF THE INVENTION
Accordingly in n first aspect, the invention may broadly be said to consist in a blower
unit for use as part of an integrated blower/humidification system for providing heated
humidified gases to a user, comprising:
an outer casing, which encloses and forms part of said blower unit, said casing including
an inlet vent through which air from atmosphere can enter said casing in use,
a humidifier compartment adapted to in use receive a humidifier unit of the type which
has a gases inlet and a gases outlet, said compartment including a heater base adapted for use with
said humidifier unit, said compartment further including a blower inlet port adapted to provide a
gases path between the interior of said casing and said humidifier unit inlet in use,
a gases path through said casing between said inlet vent and said blower inlet port,

a fan unit contained within said casing and adapted to provide a pressurised gases stream
along said gases path in use,
a power supply unit located within said casing and adapted to in use provide power to said
fan unit and said heater base,
said gases path routed over said power supply unit in order to provide a cooling air flow.
In a second aspect, the invention may broadly be said to consist in a blower unit for use
as part of an integrated blower/humidification system for providing heated humidified gases to a
user, comprising:
an outer casing, which encloses and forms part of said blower unit, said casing including
an inlet vent through which air from atmosphere can enter said casing in use,
a humidifier compartment adapted to in use receive a humidifier unit of the type which
has a gases inlet and a gases oudet, said compartment including a heater base adapted for use with
said humidifier unit, said compartment further including a blower inlet port adapted to provide a
gases path between the interior of said casing and said humidifier unit inlet in use,
a gases path through said casing between said inlet vent and said blower inlet port,
a fan unit contained within said casing and adapted to provide a pressurised gases stream
along said gases path in use,
a power supply unit located within said casing and adapted to in use provide power to said
fan unit and said heater base,
said power supply unit enclosed within a power supply sub-housing and said gases path
routed so that it passes over at least two walls of said power supply sub-housing in use in order to
provide a cooling air flow.
In a third aspect, the invention may broadly be said to consist in an integrated
blower/humidification system for providing heated humidified gases to a user, comprising:
a humidifier unit adapted to contain a volume of water and also adapted for use in
conjunction with a heater base such that said volume of water can be heated, said humidifier unit
having a gases inlet port, a gases outlet port and a top fill aperture,
an assisted breathing unit having an outer casing and including a humidifier compartment
into which said humidifier unit locates in use, said humidifier unit substantially enclosed within
said compartment, said compartment including a heater base, said assisted breathing unit further
including an inlet vent open to atmosphere on said outer casing, a blower inlet port, a single gases

path running between said inlet vent and said blower inlet port, and a means to provide a
pressurised gases stream along said gases path, in use said blower inlet port and said humidifier
gases inlet port in gaseous communication, said gases stream entering said humidifier unit via said
humidifier gases inlet port and exiting said humidifier unit via said humidifier gases outlet port,
a connection means to provide said gases stream exiting said humidifier unit to a patient
interface,
a lid unit, said lid unit adapted to close and seal said top fill aperture of said humidifier
unit and to connect with said outer casing to hold said humidifier unit rigidly in position relative
to said assisted breathing unit in use.
In a fourth aspect, the invention may broadly be said to consist in a humidifier unit
adapted for use in conjunction with an assisted breathing unit that includes a heater plate, said
humidifier unit comprising;
a humidifier chamber that includes said top fill aperture, and a heater plate that is adapted
to contact said heater base in use, the wall of said chamber having a gases inlet and a gases outlet,
an elongate inlet passage extending into said humidifier chamber from said gases inlet, said
entry passage including a first opening in that end of said entry passage spaced from the wall of
said chamber,
an elongate, exit passage extending into said humidifier chamber from said gases outlet,
said exit passage including a second opening in that end of said exit passage spaced from the wall
of said chamber,
said first and second openings aligned to face substantially vertically upwards,
a baffle means located between said first and second openings and adapted to prevent air
entering said chamber from said inlet passage from directly entering said exit passage.
In a fifth aspect, the invention may broadly be said to consist in an assisted breathing unit
comprising,
an outer casing including a humidifier compartment into which a humidifier unit can
locate in use, said compartment sized and shaped to substantially enclose said chamber, said
compartment including a heater base, said assisted breathing unit further including an inlet vent
open to atmosphere on said outer casing, a blower inlet port, a single gases path running between
said inlet vent and said blower inlet port, and a means to provide a pressurised gases stream along

said gases path, in use said blower inlet port in gaseous communication with a humidifier gases
inlet port,
a connection means to provide said gases stream exiting said humidifier unit to a patient
interface,
means'for receiving and releasably engaging a lid unit that is adapted to hold said
humidifier chamber in position in said compartment.
In a sixth aspect, the invention may broadly be said to consist in an assisted breathing
unit comprising;
an outer casing including a humidifier compartment into which a humidifier unit can
locate in use, said compartment sized and shaped to substantially enclose said chamber, said
compartment including a heater base, said assisted breathing unit further including an inlet vent
open to atmosphere on said outer casing, a blower inlet port, a gases path running between said
inlet vent and said blower inlet port, and a means to provide a pressurised gases stream along said
gases path, in use said blower inlet port in gaseous communication with a humidifier gases inlet
port,
a connection means to provide said gases stream exiting said humidifier unit to a patient
interface,
means for receiving and releasably engaging a lid unit that is adapted to hold said
humidifier chamber in position in said compartment.
In a seventh aspect, the invention may broadly be said to consist in an integrated
blower/hunudification system for providing heated humidified gases to a user, comprising:
a humidifier unit adapted to contain a volume of water and also adapted for use in
conjunction with a heater base such that said volume of water can be heated, said humidifier unit
having a gases inlet port and a gases outlet port,
an assisted breathing unit having an outer casing and including a humidifier compartment
into which said humidifier unit locates in use, said humidifier unit substantially enclosed within
said compartment, said compartment including a heater base, said assisted breathing unit further
including an inlet vent open to atmosphere on said outer casing, a blower inlet port, a gases path
running between said inlet vent and said blower inlet port, and a means to provide a pressurised
gases stream along said gases path, in use said blower inlet port and said humidifier gases inlet

port in gaseous communication, said gases stream entering said humidifier unit via said humidifier
gases inlet port and exiting said humidifier unit via said humidifier gases oudet port,
a connection means to provide said gases stream exiting said humidifier unit to a patient
interface,
said breadung unit, said compartment and said gases padi shaped and aligned to minimise
the volume of said breathing unit.
In an eighth aspect, the invention may broadly be said to consist in an integrated
blower/humidification system for providing heated humidified gases to a user, comprising:
a humidifier unit adapted to contain a volume of water and also adapted for use in
conjunction with a heater base such that said volume of water can be heated, said humidifier unit
having a gases inlet port, a gases oudet port and a top fill aperture,
an assisted breathing unit having an outer casing and including a humidifier compartment
into which said humidifier unit locates in use, said humidifier unit substantially enclosed within
said compartment, said compartment including a heater base, said assisted breathing unit further
including an inlet vent open to atmosphere on said outer casing, a blower inlet port, a gases path
running between said inlet vent and said blower inlet port, and a means to provide a pressurised
gases stream along said gases path, in use said blower inlet port and said humidifier gases inlet
port in gaseous communication, said gases stream entering said humidifier unit via said humidifier
gases inlet port and exidng said humidifier unit via said humidifier gases outlet port,
a connection means to provide said gases stream exiting said humidifier unit to a patient
interface,
a lid unit, said lid unit adapted to close and seal said top fill aperture of said humidifier
unit and to connect with said outer casing to hold said humidifier unit rigidly in position relative
to said assisted breathing unit in use.
In a ninth aspect, the present invention broadly consists in a control knob assembly that
is operable by a user to generate control signals, comprising:
a mounting plate including a recess, below which associated detector magnetic
components are situated;
an operable control knob that is securable within the aperture of the mounting plate, the
control knob having:

a button that is resibendy depressible by a user between a rest position and an operative position,
the button being biased toward the rest position and having an associated magnetic component(s)
that is arranged to move with the button; and
a boss that surrounds the button and that is rotatable either clockwise or anticlockwise
about the button by a user, the boss having an associated magnetic component(s) that is arranged
to rotate with the boss; and
control circuitry that is arranged to detect depression of the button and/or rotation of the
boss by sensing magnetic field fluctuations caused by interaction of the-magnetic components of
the button and/or boss with the detector magnetic components situated below the mounting
plate to generate control signals representing operation of the button-and/or boss by a user.
In a tenth aspect, the invention may broadly be said to consist in a control system for an
integrated assisted breathing and humidifier unit, said control system comprising;
a controller including controller memory, said controller controlling the operation of said
integrated assisted breathing and humidifier unit;
a display panel controlled by said controller; and
a user options selector, said controller responsive to changes in said options selector.
In an eleventh aspect, the invention may broadly be said to consist in a method for
altering the control settings of an integrated assisted breathing and humidifier unit having a
controller controlling the operation of said integrated assisted breathing and humidifier unit, said
method comprising the steps of:
detecting the rotational position of a rotatable user options selector;
displaying, the currently selected option, based on the rotational position of said rotatable
selector; and
detecting movement of said user options selector along the axis of rotation of said
selector, in response to said movement moving to a option chosen mode for the selected option.
This invention may also be said broadly to consist in the parts, elements and features
referred to or indicated in the specification of the application, individually or collectively, and any
or all combinations of any two or more of said parts, elements or features, and where specific
integers are mentioned herein which have known equivalents in the art to which this invention
relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

The term 'comprising' as used in this specification means 'consisting at least in part of,
that is to say when interpreting statements in this specification which include that term, the
features, prefaced by that term in each statement, all need to be present but other features can
also be present.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred form of the present invention will now be described with reference to the
accompanying drawings.
Figure 1 shows a schematic view of a user receiving humidified air from a modular
blower/humidifier system of a known, prior art, type.
Figure 2 shows a schematic view of a user receiving humidified air from an integrated
blower/humidifier system of a known, prior art, type.
Figure 3 shows a perspective view of the preferred embodiment of the integrated
blower/humidifier of the present invention, which has a separate humidifier chamber and assisted
breathing unit that are shown with the humidifier chamber in place within the blower unit ready
for use.
Figure 4 shows a perspective view of the blower unit of Figure 3, with the humidifier unit
removed (not shown).
Figure 5a shows a rear view of the blower unit of Figure 3, with a section line D-D
shown.
Figure 5b shows a cross-sectional view along section line D-D of the blower unit of
Figure 4.
Figure 6 shows an exploded view of the blower unit and the humidifier unit of Figure 3.
Figure 7 shows a schematic detail view along section line DD of the internal structure of
the blower unit.
Figure 8 shows a cutaway view of the blower unit from underneath and to the rear
looking forwards, with detail of an air inlet duct, a power supply and power supply sub-housing, a
fan, and an air path through the unit shown.
Figure 9 shows a cutaway view of the blower unit from underneath and to the rear
looking forwards, with the rearmost part of the blower unit cut away to show detail of the au path
around the power supply sub-housing.

Figures 10a and 10b show cutaway views of the blower unit from underneath and to the
rear looking forwards, with Figure 10a showing the blower unit with the base and part of the rear
wall removed, and Figure 10b showing the rear part of the blower cutaway further forward than
the view of Figure 10a, to show detail of the air path over the power supply sub-housing.
Figure 11a shows a cutaway bottom view of the blower unit of the preceding Figures,
with the base removed.
Figure lib shows a schematic view of the blower of Figure 1 la, with the air path and
turbulence shown as the air passes firsdy into the air inlet duct, then over and around the power
supply sub-housing, and then into and out of the fan.
Figure 12 shows a schematic line view of the blower unit underneath and to the rear
looking forwards, with the air path and turbulence shown as the air passes firsdy into the air inlet
duct, then over and around the power supply sub-housing, and then into and out of the fan.
Figure 13a shows a rear view of the humidifier chamber of the present invention, with a
humidifier chamber lid and a locking handle shown in exploded view above the humidifier
chamber, and a section line A-A shown.
Figure 13b shows a cross sectional view along the line A-A of the humidifier chamber,
humidifier chamber lid and locking handle of figure 13a.
Figure 14 shows a schematic cross-section of part of the front of the blower unit.
Figure 15 shows a preferred form of main menu that is displayed on a display panel of
the integrated blower/humidifier of Figure 3.
Figure 16 shows a schematic view of the internal structure of the preferred form of fan
and motor that can be used in the blower unit of Figure 5b.
Figure 17 shows a partial view of the lid of Figure 6, and a locking handle used to hold
the lid in position, with the lid and locking handle separated.
Figure 18 shows a preferred form of carry case that can be used with the breathing
assistance apparatus of the present invention, closed and upright resting on its end base.
Figure 19 shows a cutaway side view of the carry case of Figure 18, resting on its side
base, ready to be opened, with an integrated breathing assistance apparaais of the type shown in
Figure 3 located in the carry case.

1 _/
Figure 20 shows a top view of the'carry case of Figures 18 and 19, with the lid or top half
wn, and an integrated breathing assistance apparatus of the type shown in Figure 3 located
in the carry case ready for transport.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A schematic view of a user 3a receiving air from a known (prior art) modular assisted
breathing unit and humidifier system is shown in Figure 1. Pressurised air is provided from an
assisted breathing unit or blower la via a conduit 41 to a humidifier chamber 2a. Humidified,
heated and pressurised gases exit the humidifier chamber 2a via a conduit 21, and are provided to
the patient or user 3 via a user interface 4. The user interface 4 shown in Figure 1 is a nasal mask,
covering the nose of the user 3. However, it should be noted that in systems of these types, a full
face mask, nasal cannula, tracheostomy fitting, or any other suitable user interface could be
substituted for the nasal mask shown.
A schematic view of the user 3 receiving air from a known, prior art integrated
blower/humidifier unit 5 is shown in Figure 2. The system operates in the same manner as the
modular system shown in Figure 1, except that humidifier chamber 2b has been integrated with
the blower unit lb to form the integrated unit 5.
The integrated blower/humidifier unit 6 of the present invention can be substituted for
the unit 5 of Figure 2. The preferred form of the integrated blower/humidifier unit 6 is shown
assembled and ready for use in Figure 3. The unit 6 has two main parts: An integrated assisted
breathing unit 7 (also known as a blower unit), having an outer shell which forms part of the
breathing unit 7 and also encloses the working parts of the assisted breathing unit — e.g. the fan,
internal ducting and the internal control system; and a humidification unit 31 (described in detail
below).
Assisted Breathing Unit
The preferred form of assisted breathing unit or integrated unit 6 will now be described
with reference to Figures 4-17.
The integrated unit 6 consists of two main parts: an assisted breathing or blower unit 7
and a humidification unit 31. The humidification unit 31 is enclosed within the external casing of
the integrated unit 6 in use, except for the top part. The structure of the humidification unit 31 is
described in greater detail below. The blower unit 7 has an outer shell which is a generally
rectangular block with substantially vertical side and rear walls, and a front face that is angled
slighdy rearwards, In the preferred embodiment, the walls, base and top surface are all

manufactured and connected as fax as possible to minimise the occurrence of seams, and any
necessary seams are sealed. This outer shell encloses the working parts of the blower unit 7, and
forms part of the blower unit 7. As shown in Figure 4, a control knob 8 is located on the lower
section of the front face of the integrated unit 6, with a control display 9 located direcdy above
the knob 8. A patient oudet 25 is shown passing out of the rear wall of the integrated unit 6. In
the preferred embodiment, in use the free end of the oudet 25 faces upwards for ease of
connection. However, the preferred form of patient oudet 25 can be rotated to one side or the
odier to move or align it in a more convenient position for storage or for a more convenient use
position. The padent oudet 25 is adapted to allow both pneumatic and electrical connection to
one end of a conduit — e.g. conduit 21 — running between the unit 6 and a padent interface - e.g.
interface 4. An example of the type of connector that can be used and the type of dual
connection that can be made is described in US 6,953,354. It should be noted that for the
purposes of reading this specification, the patient interface can be thought of as including both
the interface 4 and the conduit 21 where it would be appropriate to read it in this manner.
In Figure 3, a locking handle 22 is shown in position on the top surface of the integrated
unit 6. The locking handle 22 is a separate item that can be unlocked and removed from the
remainder of the integrated unit 6. The locking handle 22 includes a grip 30, adapted to act as a
handle to allow a user to lift and carry the integrated unit 6, and also adapted to enable the handle
22 to be rotated from a locked position to an unlocked position. The locking handle 22 can be
releasably locked to the remainder of the integrated unit 6. The function of the locking handle 22
will be more fully described below in the 'humidifier unit' section.
Figure 4 shows the integrated unit 6 with the locking handle 22 removed and the
humidificauon unit 31 not shown. That is, just the blower unit 7 is shown. The top surface of
the blower unit 7 includes a circular humidifier aperture 1000, leading to an internal humidifier
compartment 11. The opening includes a rim 24 located around the circumference of the
opening. In use, a humidifier chamber 12 is located within the compartment 11. The humidifier
chamber 12 will be described in detail below. The humidifier chamber 12 is in use fully enclosed
inside the compartment 11, except for the uppermost part. When the chamber 12 is described as
enclosed in the blower unit 7, it can be taken to mean fully enclosed except for the uppermost
portion, as well as fully enclosed including the uppermost portion.
The internal structure of the blower unit 7 will now be described with reference to Figures
4 and 5. A heater base 23 is located at the bottom of the compartment 11. The heater base 23 is
mounted to the floor of the compartment 11 in such a way that it has a small amount of elastic or

compression resilience. That is, it can be pushed downwards a short distance within the
compartment, but will push back against any downwards force that is applied. In the absence of
any downwards force it will return to its initial position. This can be achieved by spring loading
the base 23, or by any other of the methods that are known in the associated arts. A blower inlet
port 13 and blower outlet port 14 are located on the wall of the compartment 11, towards the top
of the compartment 11. In the preferred embodiment, these blower ports 13, 14 are aligned so as
to mate with humidifier ports 15, 16 located on the humidifier chamber 12 in use (described in
detail below) so as to form a blower-to-humidifier gases route which allows gases to exit the
blower 7 and enter the humidifier chamber 12. It should be noted that other forms of blower
inlet are possible. For example a conduit running between the blower unit 7 and e.g. the lid of the
humidifier chamber 12.
As shown in Figures 7 and 8, the integrated unit 6 includes an inlet vent 101 to draw air in
from atmosphere. The integrated unit 6 also includes a mechanism for providing a pressurised air
flow from the inlet vent 101 to the humidifier chamber. This vent 101 can be located wherever is
convenient on the external surface of the integrated unit 6. In the preferred embodiment, as
shown in Figure 8, it is located on the rear face of the blower unit 7. In the preferred
embodiment, air is drawn in through the vent 101 by a fan unit 100 which acts as the preferred
form of pressured air flow mechanism (described in detail below). The air is ducted or otherwise
directed through the casing to the inlet port 13. In use, air will exit the main body of the blower
unit 7 via the inlet port 13 and then enter the humidifier chamber 12, where it is humidified and
heated, before passing out of the chamber 12 through the outlet port 14, which is directly
connected to the patient outlet 25. The heated humidified gas is then passed to the user 3 via e.g.
a conduit 21. The patient outlet 25 is adapted to enable pneumatic attachment of the patient
conduit 21, and in the preferred embodiment, electrical connection at the outlet 25 is also enabled
via an electrical connector 19. A combined electrical and pneumatic connection can be useful for
example if the conduit 21 is to be heated. Electrical heating of a conduit such as conduit 21 can
prevent or minimise the occurrence of condensation within the conduit 21. It should also be
noted that the oudet connection does not have to be via the housing of the integrated unit 6. If
required, the connection for the conduit 21 could be located directly on an oudet from humidifier
chamber 12. The preferred form and variations can generally be referred to as connection
mechanisms.
As shown in Figures 6 and 7, the inlet port 13 is offset. That is, the port is positioned
facing into or out of the corner of the integrated unit 6 between the side wall and the front face.
In contrast, outlet port 14 is direcdy aligned with the rear wall of the integrated unit 6. It can also

be seen from Figure 6 that the circular compartment 11 is sized to just fit within the generally
square plan view profile of the integrated unit 6. Offsetting the inlet port 13 towards the corner
allows a more efficient use of the space within the assisted breathing integrated unit 6, and allows
the size of the integrated blower/humidifier unit 6 to be minimised.
The locking handle 22 and the integrated unit 6 include a locking mechanism for locking the handle 22 to the integrated unit 6. In the preferred embodiment the locking mechanism is as
follows: the rim 24 includes two mating grooves 26 located just below the rim 24, spaced opposite
each other on the circumference of the rim 24. More dian two of the mating grooves 26 can be
used if required. The grooves 26 correspond to an equal number of mating lugs 27 on the locking
handle 22. The mating groove or grooves 26 have an entry point 28 on the rim 24, with the main
part of the groove 26 located slighdy below the rim 24. The lugs 27 are pushed downwards into
the entry points 28, and the handle is rotated so that the lugs enter the main part of the grooves
26 to hold the handle 22 in place. Different locking mechanisms can be used if required.
Humidifier chamber with lid
The humidifier unit 31 will now be described in more detail with particular reference to
Figures 13 and 17.
In the preferred embodiment, the humidifier unit 31 is comprised of three main parts:
humidifier chamber 12, lid 32 and locking handle 22 (counted as part of the humidifier unit for
the purpose of describing the operation of the integrated unit 6).
The preferred embodiment of the humidifier chamber 12 is an open-topped container,
with a heat conducting base. The chamber 12 is sized to fit snugly within the compartment 11 on
the integrated unit 6. That is, the chamber 12 is enclosed within the blower unit except for the
open top of the chamber 12. A fully open topped chamber 12 is the preferred form. However,
an alternative form of the chamber 12 could have a closed top surface, and would include an
opening on the chamber (not necessarily on the top surface), sized appropriately so that a user can
easily fill the chamber 12. The preferred form of chamber 12 with an open top, and the
alternative form that includes a fill opening on the top are referred to as 'open top', or 'top
openings' within this specification. The open top may also be referred to as a 'top fill aperture'.
It should also be noted that when the humidifier chamber 12 is referred to as 'enclosed', or
'substantially, enclosed' in relation to the integrated breathing assistance apparatus, this lias the
meanings defined above. The chamber 12 is generally circular, but the lower part of the rear
(relative to the integrated unit 6) is flattened as shown in Figures 13a and 13b to correspond to a
ledge 33 on the lower rear side of the compartment 11. This ensures that the chamber 12 will

always be oriented correctly in use. It should be understood that other methods of achieving the
same result could also be used. For example, the chamber 12 and integrated unit 6 could include
complimentary grooves and slots. The chamber 12 can also include features such as a fill or level
line if required. The humidifier inlet port 15 and a humidifier outlet port 16 are located in the wall
of the humidifier chamber 12, towards the top of the chamber wall. These are positioned so as to
align with the blower inlet and outlet ports 13 and 14 when the humidifier chamber 12 is in
position, forming the blowcr-to-humidifier gases route as described above. It is preferred that the
corresponding ports on the blower 7 and humidifier chamber 12 are shaped so as to minimise
airgaps. A good seal is preferred but not required. In the preferred form, the rim or perimeter of
the chamber 12 includes a chamber seal 10, formed from soft silicone or similar. When the
chamber 12 is placed in position in the humidifier compartment 11, the chamber seal 10 is
pressed against the wall or walls of the compartment 11, and the body of the chamber 12 and the
seal 10 ensure that the chamber 12 is sealed, so that air exiting the blower through the port 13
cannot escape to atmosphere. This helps ensure that a pressunscd airstream enters the humidifier
chamber 12 in use. If required, a substantially unbroken ring of sealing material such as soft
silicone can be added to the wall of the compartment 11 at or close to the upper rim of the
chamber 12, to form a compartment seal (not shown) instead of or as well as the chamber seal 10.
In alternative embodiments the ports 13, 14 are surrounded by resilient sealing gaskets such as
silicone gaskets to assist in forming a seal in use. If preferred, the resilient sealing gaskets around
the ports can be used as well as the compartment and/or chamber seals.
Air enters the humidifier chamber 12 through the humidifier inlet port 15, and passes
along a generally horizontal entry passage 34 towards the centre of the humidifier chamber 12.
Passage 34 is offset towards one of the front corners of the unit to align with the inlet port 13 as
described above. The air exits the entry passage 34 through a first aperture or opening 200 in the
centre of the humidifier chamber 12 aligned facing upwards (that is, in the top of the passage).
The air is then directed into the main part of the chamber by a baffle 35. In cross section, the
baffle 35 is T-shaped, with a vertical central portion to deflect gases entering the chamber 12, and
a substantially horizontal top 'umbrella' portion 202, which is circular in plan view, as shown in
Figures 6 and 13. Air is deflected by the baffle 35 as it exits the passage 34, and then enters the
main part of the chamber 12 where it is heated and humidified. The heated and humidified gases
then enter an exit passage 36 on the other side of the baffle 35 through a second aperture or
opening 201, with the air passing through the exit passage 36 to the chamber exit port 16 and
then into the breathing unit outlet port 14, and on to the user 4 as described above. It can be
seen that the baffle 35 prevents air from the inlet passage 34 from direcdy entering the exit

passage 36 before it has been heated and humidified. The passage and baffle arrangement also
serves the purpose of acting as a splash baffle as well as an air baffle. Water is obstructed from
entering the passages 34 and 36 if the chamber 12 is tilted while it contains water. The umbrella
portion 202 of the baffle 35 acts as a shield for the passages 34, 36, vertically occluding the
apertures 200, 201, so that when a user is pouring or refilling the chamber 12, the user cannot
direcdy pour into either of the apertures 200, 201. The top surface of the passages 34, 36 also
acts as a shield to prevent a user pouring water into the passages 34, 36. It is preferred that the
exit and entry apertures 200, 201 in the passages 34, 36 face upwards, as this helps to prevent
water or liquid in the chamber splashing into the passages 34, 36, or otherwise entering the
passages 34, 36 when the chamber 12 is tilted. The passages, 34, 36 and the baffle 35 can be
generally referred to as the baffle, or the baffle mechanism.
In use, the chamber 12 is positioned (in the correct orientation) within the compartment
11. The lid 32 is then placed on top of the chamber 12. The lid 32 is sized so that it will pass
through the top opening of the integrated unit 6, with the lower surface of the lid 32, close to the
edge, sealing onto the upper edge of the chamber 12. In the preferred embodiment, the lid 32 has
an edge perimeter portion that is aligned facing downwards. This has a central recess that is filled
with a silicone seal 70 or similar which is pressed onto the upwards facing edge of the chamber 12
when the lid 32 is in position. This arrangement is shown in Figure 13. In Figure 13 the handle
22 is also shown vertically above the lid 32 (separate from the lid 32). The lid 32 is sized to fit
into the recess shown in the handle 22 (if the handle shown in Figure 13 is pressed vertically
downwards onto the lid 32). If required, the two contacting portions of the lid 32 and the
chamber 12 can also be shaped to improve the seal between the two. The central part of the lid
32 is bulged upwards so that it will stand proud of the baffle 35. The lid 32 is placed in position
on the chamber 12 once the chamber 12 has been filled. The locking handle 22 is then positioned
above the lid 32. As has been described above, lugs 27 on the circumference of the locking
handle 22 engage with complimentary grooves 26 on the rim 24. In order to engage correctly, it is
necessary in the preferred embodiment for the locking handle 22 to be pressed or pushed
downwards, pushing both the lid 32 and the chamber 12 downwards onto the heater plate 12.
The heater plate 12 will give slighdy under the downwards pressure, allowing the locking handle
22to be rotated so that the lugs 27 engage with the grooves or slots 26. Once the downwards
force is removed, the chamber 12, lid 32, and locking handle 22 will be pressed upwards by the
reaction force from the heater plate 12, with the assembly held in place by the lugs 27 and slots
26. In the preferred embodiment, the slots 26 are shaped so that the locking handle 22 cannot be
rotated to disengage the lugs 27 without pressing the locking handle 22 downwards slighdy first.

The locking handle 22 also includes the grip 30, which in the preferred embodiment is an arched
member passing from one side of the handle 22 to the other, sized and shaped so that a user can
pass at least some of their fingers underneath, so as to manipulate the locking handle 22 and to
carry the integrated unit 6 if necessary. In the preferred embodiment, the locking handle 22 and
the lid 32 are separate items, as described. If the handle 22 is used without the lid 32, the
chamber will not be sealed, and the heated, humidified air will escape or vent to atmosphere
before entering the exit port 14. Any air diat does enter the port 14 will be at a lower pressure
than required, due to the leaking. To ensure correct operation, the lid must be used to seal the
chamber in the preferred embodiment. This ensure that there is less chance of incorrect use of
the unit. For example, if a user fills the compartment 11 direcdy without using the chamber 12,
or if a user forgets to place the lid 32 in position.
In the preferred form, the top portion of the lid 32 fits into a central recess in the handle
22, as can best be seen in Figure 6b. The lid 32 and the handle 22 are sized so that the lid 22 will
snap-fit and be held in place in the handle 22 to form an integrated lid unit. The lid 22 can be
disengaged from the handle 32 by pressing on its top surface or similar. However, it is preferred
that the snap-fit will keep them engaged in normal usage. As the handle recess and the lid 22 are
circular, they can easily rotate relative to one another when engaged. When the handle 22 is
rotated to disengage it from the integrated unit 6, it will rotate easily relative to the lid 32 (which
will not rotate easily due to the seal on the perimeter edge). When the handle 22 has been
disengaged from the integrated unit 6, it can be lifted away from the integrated unit 6 to remove
both the handle 22 and the lid 32.
It should be noted that although a round chamber 12, lid 32 and a locking mechanism
(lugs 27 and slots 26) have been described, and locking/unlocking of the lid 32 is achieved by
rotating the separate locking handle 22, this is not the only way in which this effect can be
achieved. If a different locking mechanism is used in place of the lugs 27 and grooves 26,
chambers with different profiles can be used in place of the round chamber 12 described above.
For example, spring loaded clips could be used, with the clips released by a button placed in a
convenient location, such as on a handle or on the outer surface of the integrated unit 6. A
hinged lid could also be used, with a clip and complimentary catch located on the lid and the
blower unit, to hold the lid closed in use. Alternatively or as well as, the chamber lid 32 and the
locking handle 22 could be integrated as a single unit. This single unit could either be separable
from the integrated unit 6 or the humidifier unit 31, or an integral part of it, for example a hinged
lid similar to diat suggested above. The intention of the lid 32 and handle 22 in the arrangement
described above is that a user can easily remove the lid 32 in order to access the chamber 12 for

refilling or similar, and that a user can then easily replace the lid 32 and handle 22 to hold the lid
32 and the chamber 12 in position inside the assisted breathing integrated unit 6.
It should be noted that as outlined above, use of a round chamber 12, with a generally
square profile integrated unit 6 allows an efficient use of space so that the overall size of the
integrated unit 6 can be minimised. This should be considered if using an alternative layout or
locking mechanism.
Control Knob
The preferred form of construction of the control knob assembly including operable
control knob 8, and attachment to the integrated unit 6 will now be described with particular
reference to Figure 14. The knob 8 is manipulable by a user to change the settings of the
integrated unit. This is achieved by twisting and pushing the knob 8 to generate control signals.
In the preferred embodiment, the integrated unit 6 includes a removable mounting plate
removable faceplate 37 that removably attaches onto the front face of the integrated unit 6 - e.g.
by friction-fit push clips or similar, sufficient to hold the faceplate 37 in place in use or during
transport, but allowing the faceplate 37 to be removed e.g. by pressing a knife blade under one
side and twisting or similar. The faceplate 37 includes an aperture that aligns with the control •
screen 9, so that the screen can be viewed through the aperture in use. Figure 14 shows a
schematic cross-section of the front surface of the integrated unit 6, viewed from above. For
clarity, the various elements shown in Figure 8 are shown not in contact with one another. As
shown in Figure 14, the face plate 37 includes a concave hollow, depression or recess 38, into
which the knob 8 locates in use. The depression 38 is sized and shaped so that the knob 8 fits
snugly. The bottom of the depression 38 contains a fastening mechanism 39. In the preferred
embodiment, the fastening mechanism 39 is formed as an integral part of the plate 37. In the
preferred embodiment, the fastening mechanism 39 is a ring or crown of sprung fasteners or
fastening clips 39, with their tips or upper portions 60 facing or pointing inwards. The fastening
clips 39 are aligned perpendicular to the base of the depression 38. The knob 8 is made up of a
central, non-rotating portion or button 61 and an outer, rotatable portion or boss 62 that can be
rotated either clockwise or anticlockwise by a user. The outer portion 62 is ring-shaped, with a
central aperture. The inner portion 61 has a T-shape in cross-section, with fasteners 63 integral
with the upright of the T. In use, the fasteners 63 connect with the sprung fasteners 39 to hold
the inner portion in position. The knob assembly is assembled by placing the outer (rotatable)
portion 62 of the knob 8 in position in the depression 38, and then pushing the inner (non-
rotatable) portion 61 into position. The flat upper part of the inner portion acts as a flange to

hold the outer portion 62 in position. In the preferred embodiment, the outer portion 62 also has
a slight central hollow, with the cross-portion of the T-section of the inner portion 62 fitting
snugly into this hollow so that the inner portion 61 and the outer portion 62 together form a flush
outer surface.
What has been described above is the preferred form of fastening mechanism to hold the
knob 8 in position on the faceplate 37- However, any suitable fastening mechanism could be
substituted for the one described.
The knob 8, or more specifically the outer portion 62, is fitted with a ring magnet 45. The
outer portion 62 generally has the form of a hollow cup, with the open face facing inwards
towards the centre of the depression 38 in use. The ring magnet 45 is fitted running around the
inside of the outer portion, just below the rim. The centre of the ring magnet 45 is aligned with
the axis of rotation of the knob 8. As the outer portion 62 rotates, the ring magnet 45 also
rotates.
The front face or wall 50 of the assisted breathing or integrated unit 6 is located behind
the faceplate 37. The front face 50 includes an aperture 43, through which the rearmost part of
the depression or recess 38 passes in use. A connector board 44 is located just behind, and
generally planar with, both the faceplate 37 and the front face 50 of the integrated unit 6.
Magnetic or magnetised sections 46 are embedded on the inner surface of the connector board
44. These are positioned to as to form a generally circular shape, corresponding to the ring
magnet 45, so that the magnetised sections 46 align with the ring magnet 45. The magnetic fields
of the ring magnet 45 and the magnetised sections 46 (detector magnetic components, or boss
detector magnetic components) interact as the knob is rotated in use. Control circuitry and
sensors (not shown) located within the blower unit 6 are connected to the ring magnet 45 so that
as the boss portion 62 of the knob 8 is turned it can detect the fluctuations of the interacting
magnetic fields. In the preferred form, the ring magnet 45 is continuous (that is, a continuous
annular component), but divided into a number of discrete magnetic sections (That is, there are
no physical gaps between the sections). 1 he number of sections can be varied depending on the
number of positions required. One advantage of using a ring magnet such as ring magnet 45 is
that is has discrete sections. This means that as the boss portion of the knob 8 is rotated, it will
have a number of discrete positions, having preferred 'rest' positions as the fields of the
magnetised sections 46 and the fields of the sections of the ring magnet 45 interact to reach an
equilibrium point, an effect known as 'cogging'. The outer portion 62 of the knob 8 will rest at
these equilibrium points until acted on by an external force - e.g. a user exerting a rotational force

on the rotatnble outer portion 62 of knob 8. The knob 8 will therefore tend to naturally 'jump'
from one rest position to the next as it is rotated. As the relative positions of the magnets 45 and
46 changes, the fluctuations of the relative magnetic fields changes is detected by the sensors, and
the results of the fluctuations are passed to the control circuitry 300 located inside the housing of
the respirator 7 (e.g. located on the circuit board 44), which alters the output parameters of the
integrated unit 6 according to pre-programmed responses (e.g. altering the power to the heater
base 23, fan speed, etc) as required by a user.
The preferred form of ring magnet 45 and magnetised sections 46 has been described
above. It should be noted that the positions of the ring magnet 45 and magnetised sections 46
could be reversed. Also, the ring magnet 45 could be composed of discrete sections, with gaps
between them. That is, an annular arrangement of individual magnetic components. Magnetised
sections 46 have been described. These could be actual magnets, or alternatively these could be
electrotnagnetised elements that act both as magnets and sensors to exert a cogging force and
provide positioning feedback.
In the preferred embodiment, the knob 8 is also adapted to allow limited movement along
its axis of rotation 51. That is, it can be pressed inwards to act as a button. This can be achieved
in a number of ways. However, in the preferred embodiment, a spring (not shown) is placed
inside' the circle or crown of the preferred form of fastening mechanism 39. When cmplaced, this
spring is slightly under compression, and pushes outwards against the knob 8 so that it has a rest
position when not depressed and an operative position when depressed. When pressed inwards
towards the integrated unit 6, the spring is compressed slightly more, and will act to return the
knob 8 to its initial position once the pressing force is removed. The centre of the knob S also
holds a magnet 48. A corresponding central magnet 49 (or button detector magnetic component)
is located at the centre of the circle formed by sections 46. In a similar fashion to that described
above, as the relative positions of the magnets 48 and 49 changes, the fluctuations of the relative
magnetic fields are detected, and these changes are passed to a control unit which vanes the
output parameters of the integrated unit 6 accordingly. For example, using the arrangement
described above, the knob 8 can be rotated clockwise and anticlockwise to scroll between menu
options, and then pressed inwards to choose the option to which the user has scrolled. The knob
8 can also be used as e.g. an on/off switch, either by scrolling to the required on/off menu choice
and pressing, or by pressing and holding the knob in for a longer period than would naturally
occur if the unit 6 was accidentally knocked - for example 5 seconds. Alternatively, the controls
could be set so that a user is required to pull the knob 8 slightly out from the unit 6 to turn it off.

What has been described above is an assembly where the medical device (blower unit 7)
includes a faceplate 37 which includes a recess, and which fits over the front face 50 of the blower
7. The faceplate is unbroken, in that there are no apertures or gaps through which moisture or
dirt can enter the medical device. Also, the components external to the blower 7 are not moisture
or dirt sensitive, so if they get wet or dirty, their operational effectiveness is not adversely affected.
It should be noted that what is described above is the preferred embodiment, and the principles
of the operauon could be applied equally well to a device which does not include a separate
faceplate, and which has a single flat face (i.e. no recess), with magnetic elements 46, 63 located
behind the face, and the control knob, boss, fastening mechanism, etc located external to the face.
It should also be noted that another possible variation of the layout described above could also be
used, with the front face 50 unbroken and including a recess, and the faceplate including an
aperture through which the control knob locates into the recess on the faceplate. It should also
be noted that the faceplate does not have to present at all, but is present in the preferred forms.
Control Menu
The preferred form of display shown on the display panel 9 is shown in Figure 15. In the
preferred embodiment, the control menu as displayed on the display 9 is a single layer menu, in
order to keep the operauon of the unit 6 simple. In the preferred embodiment, the display is an
LCD display, with a circular ring of options around the outside of the display. As the knob 8 is
rotated, each of the options will light up in turn. When the knob is depressed, that option will be
chosen. Once an opuon is chosen, for example 'output power', the level of this parameter can be
adjusted by rotating the knob 8 clockwise and anticlockwise. A user can then exit this submenu
and return to the main menu bv, for example, tapping the knob inwards or pulling it outwards.
The control circuitry can be programmed as required. Other options can be pre-programmed as
required. For example, pushing and holding in the knob 8 (or pulling it outwards and holding it
out) could turn the unit off. It is preferred that the discrete posiuons (the 'cogging' positions) that
the knob 8 reaches as it is rotated correspond to different menu options.
Blower Unit
The internal structure of the blower unit 7 will now be described with reference to Figures
5 and 7-11. In the preferred embodiment, heater base 23 is located at the bottom of the
compartment 11, as described above. It should be noted that the blower unit and humidification
chamber could be configured so that the volume of water withm the humidifier chamber is heated
e.g. through the side walls. That is, contact with a heater element or unit through a heat
conducting surface on the side wall of the chamber, rather than on the base of the chamber. This

configuration would achieve substantially the same effect. However, heating through the base is
preferred for reasons of simplifying the chamber construction and overall operation of the
heater/humidifier unit. When 'heater base' is referred to in this specification, it should be taken
to mean heating through the base of the humidifier chamber, or alternatively the side walls.
As described above, the integrated unit 6 includes an inlet vent 101 to draw air in from
atmosphere. The integrated unit 6 also includes a mechanism and structure by which a
pressurised air flow is provided from the inlet vent 101 to the humidifier chamber. The vent 101
can be located wherever is convenient on the external surface of the integrated unit 6, but in the
preferred embodiment, as shown in Figures 7 and 8, it is located on the rear face of the blower
unit 7, on the right hand side of the rear face (right hand side when looking forwards). In the
preferred embodiment, air is drawn in through the vent 101 by a fan unit 100 which provides a
pressurised gases stream through the blower unit 7. The pressurised gases stream is ducted or
otherwise directed from the inlet vent 101 through the casing to the humidifier inlet port 13. The
air path and the ducting will be described in detail in the 'Fan Unit and Air Path' section below.
In use, air exits the main body of the blower unit 7 via the inlet port 13 and enters the humidifier
chamber 12, where it is humidified and heated, before passing out of the chamber 12 through the
oudet port 14, which is directly connected to the patient outlet 25. The heated humidified gas is
then passed to the user 3 via e.g. a conduit 21. The patient oudet 25 is adapted to enable
pneumatic attachment of the patient conduit 21, and in the preferred embodiment, electrical
connection at the outlet 25 is also enabled via an electrical connector 19.
As shown in Figures 4 and 6. the inlet port 13 is offset. That is, the port is positioned
facing into or out of the corner of the integrated unit 6 between the side wall and the front face.
In contrast, outlet port 14 is directly aligned with the rear wall of the integrated unit 6. It can also
be seen that the circular compartment 11 is sized to just fit within the generally square plan view
profile of the integrated unit 6. Offsetting the inlet port 13 towards the corner allows a more
efficient use of the space within the assisted breathing integrated unit 6, and allows the size of the
integrated blower/humidifier unit 6 to be minimised.
Fan Unit
The fan unit and ducting of the preferred embodiment will now be described with
reference to Figures 5, 7-12 and 16. The fan unit 100 is intended to sit in the recess 400 shown in
Figure 5b. Air is drawn into the fan unit 100 through an inlet vent 101. Once inside the housing ,
the air is then is drawn upwards into the casing of the fan unit 100 through an aperture 110 in the
centre of the casing of the fan unit 100, and is directed outwards through a duct 120 (shown

schematically as hidden detail in Figure 16) to the inlet 13. The duct 120 runs from the recess 400
up between the side wall and the front wall of the integrated unit 6. The air path through the fan
unit is shown by arrows 130. In the preferred embodiment, fan unit 100 is electromagnetically
powered, with magnetic segments 111 interacting with electromagnetic coils 112, located above
the fan unit 100, as shown in Figure 7. The fan 110 is held in place by a bearing unit 113 that
includes a spindle for the fan 110.
Fan Unit and Air Path
The fan unit and ducting of the preferred embodiment will now be described with
particular reference to Figures 8 to 12. A power supply sub-housing 500 is located within and
integrated with the outer housing or outer shell of the breathing unit 7. The power supply sub-
housing 500 is a rectangular cuboid structure at the rear of the blower unit 7, integrated as part of
the rear wall 80 of the blower unit 7. The cuboid sub-housing 500 shares one of its two largest
faces with the rear wall 80 of the blower unit 7 (although it should be noted that the outer
dimensions of the sub-housing 500 are substantially less than the dimensions of the rear wall 80).
The other large face 510 is common with the fan recess 400, and the humidifier aperture 1000.
The sub-housing 500 is generally centrally located on the inner rear wall of the blower unit 7.
Once the unit is assembled, the sub-housing 500 is substantially closed off from atmosphere and
the rest of the internal volume of the outer shell of the blower unit 7, apart from small apertures
necessary for external electrical connections or similar (not shown). The power supply
component board 501 is comprised of electrical components connected to a mother board, and
slotted into the space within the sub-housing 500 during assembly. It is not necessary to detail or
individually number all of the components used to make up the power supply component board
501, as the make-up and variations of the construction of power supply boards is well-known in
the art. However, it should be noted that these components generate heat during use, which
cannot dissipate or vent to atmosphere due to the power supply being enclosed. This heat
therefore builds up, potentially leading to less efficient operation. It is preferred that the sub-
housing 500 is sealed or enclosed in the sub-housing 500 in this manner in order to protect the
components of the power supply component board 501, so that dirt, moisture or similar cannot
enter the sub-housing 500. However, the power supply component board could be merely-
located within the external casing or shell of the blower unit 7. It should be noted that when
'power supply' or 'power supply unit' are referred to in this specification, this means either the
power supply sub-housing 500, the power supply component board 501, or both together.

In order to help reduce the temperature of the sub-housing 500 and the temperature of
the components of the power supply component board 501 in the sub-housing 500, air from
atmosphere is drawn into the housing by the fan unit 100 and then ducted directly over the power
supply unit sub-housing 500 to cool the power supply component board 501. It is preferred that
the air is ducted over the sub-housing 500 directly after it enters the outer housing of the
integrated unit 6, as the air will be at its coolest at this point - direct from the atmosphere. In
order to most effectively cool the power supply component board 501 and the sub-housing 500,
the air is ducted over the greatest possible surface area of the sub-housing 500, while still
maintaining the integrity and operation of the integrated unit 6, and still maintaining a practical
compact and integrated design.
Air from atmosphere is drawn in through the air inlet vent 101, the side of which is
substantially the same height as one of the side walls of the sub-housing 500. In the preferred
embodiment, the inlet 101 is directly next to the sub-housing 500. It should also be noted that in
the preferred form, the height of the air inlet 101 is substantially the same as the dimension of the
neighbouring wall 502. The air entering the external shell through the inlet 101 therefore
immediately contacts the side wall 502 of the sub-housing 500. This first contact is made across
substantially the entire surface area of the wall, as the height dimension of the neighbouring vent
101 is substantially the same as the height or length of the wall 502. This has the advantage that
all the air contacting this.wall will be at atmospheric temperature as it contacts the wall. The ait is
then drawn by the fan 100 upwards and across the top wall 503 of the sub-housing 500, passing
across or over the entire outer surface area of the top wall 503. The air is then ducted down the
other, or inner side wall 504 of the sub-housing 500, passing across the enure outer surface area
of wall 504. It should be noted that the walls of the sub-housing 500 are as thin as is practical in
order to minimise their insulating effect, and maximise heat transfer between the air flow and the
power supply board. The air is then drawn inwards, away from the power supply, along the
curved path 505, through aperture 506 into the recess 400 and then into the fan unit 100. Air is
drawn into the fan unit 100 through aperture 110, and is dien directed outwards through a
plenum chamber or duct 120 inside the blower 7 to the inlet 13 ( duct 120 is shown schematically
and for the purposes of illustration only as hidden detail in Figure 16. The representation of the
duct 120 as shown in Figure 16 does not necessarily match the actual path or size of the duct).
The duct 120 runs from the recess 400 up between the right side wall (from behind looking
forwards) and the front wall of the integrated unit 6, up to the blower inlet port 13.
It can be seen that for an outer casing with a sub-housing 500 and air path configured in
this manner, air passes over the enure surface area of diree walls (502, 503, 504) of the sub-

housing 500, substantially adding to the cooling of the power supply component board 501. This
is the most preferred configuration of the cooling path, as manufacture in this configuration
allows repeatability and a high number of units within design tolerance, while minimising costs. It
has been found that this configuration gives the most efficient use of both space and air cooling,
allowing a good degree of cooling, while still ensuring the unit 6 can be configured compacdy to
minimise footprint. It should be.noted that if the power supply component board 501 is not
enclosed in a sub-housing, the cooling air can be ducted directed over the board and the
components thereon.
Other configurations are possible. For example, the air could be ducted along a space
between the large wall 510 of the sub-housing 500, and the rear wall of the humidifier aperture
1000. However, in order to make this configuration work effectively, without the air in this space
stagnating, the gap between the fan recess 400 and the power supply sub-housing 500 has to be
over a certain size, arid this can detract from the overall compact nature of the overall structure.
Furthermore, it can add to the manufacturing difficulty. It should also be noted that the blower
unit could be redesigned to allow the ail- path to pass over the lower wall of the sub-housing, as
well as or instead of, the side and upper walls.
As described above, the sub-housing 500 is located at the rear of the blower unit 7. It
could of course be located anywhere suitable, such as the sides or base, with the air ducting and
inlet configured and located accordingly. The rear is preferred as this configuration allows the
other elements of the blower unit to be configured to minimise the overall device 'footprint'.
In the most preferred form, the outer surfaces of the walls 502, 503 and 504 are ribbed, in
order to increase the surface area available for cooling, and to aid in heat dissipation by acting in a
similar manner to heat sinks. Also, in the most preferred form, air flows over at least two and
preferably three walls of the sub-housing 500 in order to maximise the cooling.
Carry Case
As has been noted above, one problem that can occur when a user packs their breathing
assistance apparatus in a case for travel is forgetting to empty the humidifier chamber, and the
contents may then spill during travel, causing at least inconvenience. It is a long felt want by users
of domestic breathing assistance apparatus that this problem is addressed.
In the preferred embodiment, a carry case 600 is used with the integrated unit 6 described
above to help overcome this problem. When a user wishes to pack their breathing assistance
device for transport, the carry case 600 can be used.

The carry case 600 is shown in Figures 18-20. The carry case 600 is formed from a rigid
plastic in the preferred embodiment. The case 600 in the preferred form comes in two parts or
halves, an upper half 604 and a lower half 605 ('half is used in this context as a term of
convenience and does not necessarily indicate that the upper and lower halves are required to be
exacdy or even close to the same size). In the closed position, the carry case 600 has one
generally flat end 601, with the opposite end 602 coming to a rounded point when viewed side on.
It is preferred that end 602 includes a handle 609 to aid a user in transporting the case 600. In the
preferred form, the handle 609 is formed when the case is closed, the upper and lower halves 604,
605 including apertures which align to form one aperture when the case is closed, a user gripping
the handle portion thus formed. The parts tat form the handle are preferably rounded, and sized
to facilitate their acting as a handle. The case 600 can be stood upright and rested on the flat end,
or end base 601, in use. Alternatively, the carry case can be rested on the side base 603 which
forms the lower side of the lower half 605. It should be noted that 'upper' and 'lower' are only
directional indicators when the-carry case 600 is resting on the side base 603. The two halves are
connected by hinges - the upper half 604 attached to the lower half 605 so that the case can be
opened by e.g. rotating or pivoting the upper half 605 relative to the stationary lower half 605,
with the case 600 resting on side base 603, for packing or unpacking. In the fully closed position,
the edges of the two come together to enclose a volume of space or an internal volume of the
case. The hinges are adapted to allow the two halves a full range of movement - e.g. substantially
180 degrees of rotation relative to one another. This allows the upper half 604 to be rotated far
enough that its outer surface can rest on the same surface as the lower half 605, for example a
table or similar, and a user can freely access the inside of the case. In the preferred embodiment,
the hinges 610 are located at the flat end 601, and form part of the flat base in use. The inside
contains packaging ot padding 606, in the preferred form including a pocket or recess 60S formed
by moulding and shaping the padding 606, so that the pocket 608 conforms generally to the
external shape and dimensions of the blower unit 7, so that at least the lower portion of the
blower unit can be placed in the recess 608 in the packaging 606 in an upright position, with the
packaging or padding 606 partially enclosing at least the lower portion of the blower unit 7, to
hold the blower unit 7 securely in position during transport. As described above, the preferred
form of chamber 31 is a top fill chamber with a removable lid 32. To prevent the user from
inadvertendy packing their integrated unit 6 away with chamber 31 still partially full and
containing liquid, the carry case 600 is adapted in the following manner so that the case 600
cannot be closed fully if the lid 32 is still in position on the chamber 31. It should be noted at
different forms of the carry case could be used to transport other types of systems that provide

heated, humidified gases to a user. For example, systems that have push fit chambers filled
through their inlets or outlets, rather than through a top fill aperture.
When the user needs to transport their integrated blower/humidifier unit, the user packs
the integrated unit 6 in the earn- case 600 by placing the integrated unit 6 in recess 608 in the
packaging 606, the recess 608 shaped to enclose at least the base of the integrated unit 6. It is
intended that the case 600 is as compact as possible. This helps a user to transport their unit as,
for example, hand luggage on an aircraft, as it can be fitted in an overhead locker. Therefore, in
the preferred form, the humidifier chamber 31 is located in the same position in which it is used
in the blower 7, and not in a separate recess. The upper half 604 of the case 600 includes at least
one protrusion 607 extending inwards from the inner surface of the upper half 604 (i.e.
downwards towards lower half 605). The at least one prouxision 607 is sized and shaped so that
the upper half and lower half 604, 605 cannot be brought fully together (i.e. the case 600 cannot
be closed) when the humidifier chamber lid 32 is sdll in position on the chamber 31. When the
humidifier chamber lid 31 is removed, the protrusion or protrusions 607 fit down inside the
chamber 31. The lid 32 dierefore has to be removed from the chamber 31 before the carry case
600 can be shut. It is preferred that the separate handle 22 can be located onto the blower unit 7,
with the protrusion or protrusions 607 extending past the handle 22 to extend downwards into
the chamber 31. The carry case 600 is preferably adapted to include an internal pocket or similar
— e.g. in the packaging 606 - which the user can use to store the lid 32 for travel.
It is preferred that the carry case can also be fitted with a strap or straps, to allow it to be
carried in the same manner that a daysac or small knapsack would be carried, or slung over one
shoulder and carried by one strap.
It should be noted that blower unit 7 is used as an example for the above described
preferred form of carry case. In other, alternative forms, the carry case is adapted to earn'
respiratory humidification systems of the type where the humidifier chamber and the blower unit
rigidly mate. In this alternative form, the padding includes a first pocket and a second pocket.
The first pocket is adapted to enclose at least the base of the blower unit, and the second pocket
is adapted to at least partly enclose the humidifier chamber. The two pockets are separate, so that
the humidifier chamber must be disconnected from the blower before the chamber and the
blower can be placed in their respective pockets. That is, the blower and the chamber cannot be
mated to be correcdy stored in the case in their respecdve pockets. The inner surface of the
upper half includes a protrusion, facing inwards. When the case is closed, the protrusion locates
into a space adjacent to the blower pocket, and ensures that the blower cannot be placed into the

first pocket with the chamber rigidly mated to the blower, and the lid them closed. The
protrusion will interfere with the chamber if a user attempts to close the lid while the chamber is
in position on the blower.

CLAIMS
What is claimed is:
1. A blower unit for use as part of an integrated blower/humidification system for providing
heated humidified gases to a user, comprising:
an outer casing, which encloses and forms part of said blower unit, said casing including
an inlet vent through which air from atmosphere can enter said casing in use,
a humidifier compartment adapted to in use receive a humidifier unit of the type which in
use contains a volume of water and which has a gases inlet and a separate gases outlet, said
compartment including a heater base adapted for use with said humidifier unit, said compartment
further including a blower inlet port adapted to align with said humidifier unit inlet to provide a
gases route between the interior of said casing and said humidifier unit in use,
a gases path through said casing between said inlet vent and said blower inlet port,
a fan unit contained within said casing and adapted to provide a pressurised gases stream
. along said gases path in use,
a power supply unit located within said casing and adapted to in use provide power to said
fan unit and said heater base,
said gases path routed over said power supply unit in order to provide a cooling air flow.
2. A blower unit as claimed in claim 1 wherein said power supply is enclosed within a
power supply sub-housing located in said casing, and said gases path is routed so as to pass over
at least two walls of said power supply sub-housing in use.
3. A blower unit for use as part of an integrated blower/humidification system for providing
heated humidified gases to a user, comprising:
an outer casing, which encloses and forms part of said blower unit, said casing including
an inlet vent through which air from atmosphere can enter said casing in use,
a humidifier compartment adapted to in use receive a humidifier unit of the type which in
use contains a volume of water and which has a gases inlet and a separate gases oudet, said
compartment including a heater base adapted for use with said humidifier unit, said compartment
further including a blower inlet port adapted to align with said humidifier unit inlet to provide a
gases route between the interior of said casing and said humidifier unit in use,
a gases path through said casing between said inlet vent and said.blower inlet pprt,

a fan unit contained within said casing and adapted to provide a pressurised gases stream
along said gases path in use,
a power supply unit located within said casing and adapted to in use provide power to said
fan unit and said heater base,
said power supply unit enclosed within a power supply sub-housing, and said gases path
routed in such a manner that said gases path passes over at least two walls of said power supply
sub-housing in use in order to provide a cooling air flow.
4. A blower unit as. claimed in claim 3 wherein said gases path passes over at least one side
wall of said power supply sub-housing.
5. A blower unit as claimed in claim 4 wherein said gases path also passes over the top wall
of said power supply sub-housing:
6. A blower unit as claimed in claim 5 wherein said gases path also passes over a second
side wall of said power supply sub-housing.
7. A blower unit as claimed in claim 6 wherein said inlet vent is located directly next to said
one wall of said power supply sub-housing.
8. A blower unit as claimed in claim 7 wherein said inlet vent is sized so that the side of said
vent and the adjourning power supply wall are substantially similarly dimensioned.
y. A blower unit as claimed in any one of claims 4 to 8 wherein said walls of said sub-
housing are ribbed to increase the surface area available for cooling:
10. A blower unit as claimed in claim 9 wherein said power supply sub-housing is located at
the rear of said casing.
11. A blower unit as claimed in claim 10 wherein said inlet vent is located on the rear wall of
said casing.
12. A blower unit as claimed in claim 11 wherein said power supply sub-liousing is
substantially centrally located on said rear wall.
13. A blower unit as claimed in claim 12 wherein the interior walls of said sub-housing are
thin, to minimise their insulating effect and maximise heat transfer between the air flow and the
power supply board.
14. A blower unit as claimed in claim 13 wherein said blower unit also includes a plenum
chamber located in said gases path between said inlet vent and said blower inlet port and

downstream of said fan unit, said fan unit and said blower unit configured so that gases exit said
fan unit at an angle to the walls of said plenum chamber.
15. An integrated blower and humidification system for providing heated humidified gases to
a user, comprising:
a humidifier unit adapted to contain a volume of water and also adapted for use in
conjunction with a heater base such that said volume of water can be heated, said humidifier unit
having a gases inlet port, a gases outlet port and a top fill aperture,
a blower unit having an outer casing and including a humidifier compartment into which
said humidifier unit locates in use, said humidifier unit substantially enclosed within said
compartment in use, said compartment including a heater base, said blower unit further including
an inlet vent open to atmosphere on said outer casing, a blower inlet port, a gases path running
between said inlet vent and said blower inlet port, and a fan unit to provide a pressurised gases
stream along said gases path, in use said blower inlet port and said humidifier gases inlet port
aligned to provide a gases route for gases exiting said blower unit via said blower inlet port and
entering said humidifier unit via said humidifier gases inlet port, said gases exiting said humidifier
unit via said humidifier gases oudet port,
a connector to allow said gases stream exiting said humidifier unit to enter a patient
interface,
a lid unit, said lid unit and said blower unit adapted to mutually connect in such a manner
that said lid unit closes and seals said chamber, and said chamber is held in position in said
humidifier compartment.
16. An integrated blower and humidification system as claimed in claim 15 wherein said
humidifier unit comprises;
a humidifier chamber that includes said top fill aperture, and a heater plate that is adapted
to contact said heater base in use, said chamber having a gases inlet and a separate gases outlet,
an elongate inlet passage extending into said humidifier, chamber from said gases inlet, said
inlet passage including a first opening in that end of said entry passage spaced from the wall of
said chamber,
an elongate exit passage extending into said humidifier chamber from said gases outlet,
said exit passage including a second opening in that end of said exit passage spaced from the wall
of said chamber,

said first and second openings aligned to face upwards when said chamber is in use, and
a baffle located between said first and second openings and adapted to prevent air that
enters said chamber from said inlet passage from directly entering said exit passage.
17 An integrated blower and humidification system as claimed in claim 16 wherein said
baffle is sized and shaped to vertically occlude said first and second openings.
18. An integrated blower and humidification system as claimed in any one of claims 15 to 17
wherein said lid unit comprises separate lid and handle portions, said handle portion releasably
connectable to said lid portion in such a manner that said handle can freely rotate when
connected to said lid portion, said lid portion adapted to close and seal said top fill aperture, said
handle portion and said blower unit adapted to mutually connect in such a manner that said lid
portion is held in position on said chamber, and said chamber is held in position in said
humidifier compartment.
19. An integrated blower and humidification system as claimed in claim 18 wherein said
heater base is located at the bottom of said humidifier compartment, said heater base spring
loaded, said base under compression tension when said humidifier chamber and lid portion are in
position and said handle portion is in position and engaged with said blower unit.
20. An integrated blower and humidification system as claimed in claim 19 wherein said
blower unit includes a plurality of grooves and said handle portion includes a plurality of
complimentary mating lugs, said lugs releasably engaging with said grooves as said handle portion
is depressed and rotated.
21. An integrated blower and humidification system as claimed in claim 20 wherein said lid
portion includes a circular top portion, and said handle includes a circular central recess, said
circular top portion sized to fit into said central recess, said handle and said lid engaging by snap
fit connection.
22. An integrated blower and humidification system as claimed in claim 21 wherein said lid
includes a silicone seal sized and shaped to fit around and seal on the perimeter of said top fill
aperture in use.
23. An integrated blower and humidification system as claimed in claim 22 wherein said
blower unit includes a blower outlet port, adapted to align with said humidifier oudet port in use
and form a gases route for gases exiting said chamber, and

said connector is mounted on said outer casing and is in gaseous communication with
said blower outlet port.
24. An integrated blower and humidification system as claimed in claim 23 wherein said
connector is adapted to allow both pneumatic and electrical connection between said connector
and said patient interface.
25. An integrated blower and humidification system as claimed in claim 24 wherein said
humidifier chamberwill vent to atmosphere unless both of said lid portion and said handle
portion are in position, and said handle portion is engaged with said blower unit.
26. An integrated blower and humidification system as claimed in claim 25 wherein said
chamber and said compartment are mutually shaped such that said chamber will only fit into said
compartment in a single orientation.
27. An integrated blower and humidification system as claimed in claim 26 wherein said
chamber and said compartment are substantially" circular in plan view, except for complimentary
flat spots on the perimeter of each of said chamber and said compartment, said flat spots shaped
such that said chamber will only fit into said compartment in one orientation.
28. An integrated blower and humidification system as claimed in claim 27 wherein said
chamber includes a chamber seal running around the top edge of said chamber adapted to seal
against said compartment in use.
29. An integrated blower and humidification system as claimed in claim 28 wherein said
compartment includes a compartment seal, said compartment seal aligning with said chamber seal
in use, when said chamber is located in said compartment.
30. An integrated blower and humidification system as claimed in claim 27 wherein said
blower inlet port and said blower outlet port include silicone seals adapted to substantially seal
between said humidifier inlet port and said humidifier outlet port respectively in use.
31. An integrated blower and humidification system as claimed in any one of claims 27 to 30
wherein said outer casing is substantially rectangular in plan view, said compartment shaped so
that in plan view there is a gap between the perimeter of said compartment and at least one corner
of said outer casing, said blower inlet pOrt located on the perimeter wall of said compartment
aligned with said gap and towards the top of said compartment, at least part of said gases path
running substantially vertically within said gap along the height of said compartment.

32. An integrated blower and hurnidification system as claimed in claim 31 wherein said
compartmenc is substantially circular in plan view.
33. A humidifier unit adapted for use in conjunction with an assisted breathing unit that
includes a heater plate, said humidifier unit comprising;
a humidifier chamber that includes a top fill aperture, and a heater plate that is adapted to
contact said heater base in use, said chamber having a gases inlet and a separate gases oudet,
an elongate inlet passage extending into said humidifier chamber from said gases inlet, said
entry passage including a first opening in that end of said entry passage spaced from the wall of
said chamber,
an elongate exit passage extending into said humidifier chamber from said gases outlet,
said exit passage including a second opening in that end of said exit passage spaced from the wall
of said chamber,
said fust and second openings aligned to face upwards,
a baffle located between said first and second openings and adapted to prevent gases
which enter said chamber from said inlet passage from directly entering said exit passage.
34. A humidifier unit as claimed in claim 33 wherein said baffle is sized and shaped to
vertically occlude said first and second openings.
35. A humidifier unit as claimed in claim 34 wherein said humidifier unit also includes a lid
unit, adapted to close and seal said open top of said humidifier chamber in use, and to connect
with said assisted breathing unit to hold said humidifier chamber in position in use.
36. A humidifier unit as claimed in claim 35 wherein said lid unit comprises a separate lid
portion and a handle portion, said handle portion releasably connecting to said lid portion in such
a manner that said handle can freely rotate while connected to said lid portion, said lid portion
adapted to seal on said open top of said humidifier chamber, said handle portion adapted to
connect with said blower unit.
37. A humidifier unit as claimed in claim 35 wherein said exit passage and said entry passage
are angled when viewed in the vertical plane.
38. A humidifier unit as claimed in claim 37 wherein said chamber includes a chamber seal
running around the top edge of said chamber.
39. An integrated blower/humidificauon system for providing heated humidified gases to a
user, comprising:

a blower unit having an outer casing and including a humidifier compartment into which a
humidifier unit locates in use, said compartment adapted so that said humidifier unit is
substantially enclosed within said compartment in use, said compartment including a heater base,
said blower unit further including an inlet vent on said outer casing adapted to allow gases from
atmosphere to enter said casing, a blower inlet port opening into said compartment, a gases path
running between said inlet vent and said blower inlet port, and a fan unit adapted to provide a
pressurised gases stream along said gases path,
a humidifier unit adapted to contain a volume of water and also adapted for use in
conjunction with said heater base such that said volume of water can be heated, said humidifier
unit having a gases inlet port and a gases outlet port,
in use, said blower inlet port and said humidifier gases inlet port aligning to provide a
gases route for gases exiting said blower unit and entering said humidifier chamber via said
humidifier gases inlet port, said gases stream exiting said humidifier unit via said humidifier gases
outlet port,
said blower unit, said compartment and said gases path shaped and aligned to minimise
the volume of said breathing unit.
40. An integrated blower/humidification system as claimed in claim 39 wherein said blower
unit further includes a blower oudet port opening onto said compartment, said blower outlet port
and said humidifier gases outlet port mutually adapted to align in use to provide a path for gases
exiting said chamber, said blower unit further including a connector adapted to connect with a
patient interface in use, said blower unit including a gases exit path between said blower outlet
port and said connector, said gases in use exiting said blower unit via said connector, and entering
said patient interface.
41. An integrated blower/humidification system as claimed in claim 39 or claim 40 wherein
said breathing unit is substantially rectangular in plan view, said compartment shaped so that in
plan view there is a gap between the perimeter of said compartment and at least one corner of
said breathing unit, said blower inlet port located on the perimeter wall of said compartment
aligned with said gap and towards the top of said compartment, said gases path running
substantially vertically within said gap along the height of said compartment.
42. An integrated blower/humidificatipn system as claimed in claim 41 wherein said
compartment is substantially circular in plan view, and has a diameter substantially similar to, but
slightly less than, the external depth and width dimensions of said blower unit, said fan unit

located below said compartment, control circuitry for said blower unit located directly behind the
front face of said blower unit, the power supply for said blower unit located directly behind the
rear wall of said blower and adjacent to said inlet vent.
43. An integrated blower/humidification system as claimed in claim 42 wherein said
humidifier unit includes a top fill aperture, and a lid unit, said lid unit adapted to close and seal
said top fill aperture of said humidifier unit and to connect with said outer casing to hold said
humidifier unit rigidly in position relative to said blower unit in use.
44. A medical device that includes a control knob assembly located on one side of said
medical device and which is operable by a user to generate control signals; said medical device
including detector magnetic components located inside said medical device, and a device fastener
located on the outside of said device, said control knob assembly comprising;
an operable control knob that includes a knob fastener, said knob fastener and said device
fastener co-operatively engaging to secure said control knob assembly in position on said device,
said control knob resiliency depressible by a user between a rest position and an operative
position, said control knob being biased toward said rest position and having at least one
associated knob magnetic component that is arranged to move with the control knob,
a boss that surrounds said control knob and which is rotatable either clockwise or
anticlockwise about said control knob by a user, said boss having at least one associated boss
magnetic component arranged to rotate with the boss,
said medical device including control circuitry adapted to separately detect both
depression of said button and rotation of said boss by sensing magnetic field fluctuations caused
by interaction of said boss magnetic components and said knob magnetic components with the
detector magnetic components and generating control signals which represent operation of the
control knob assembly by a user,
said side of said medical device unbroken.
45. A medical device as claimed in claim 44 wherein said boss magnetic components form a
ring magnet, and at least part of said detector magnetic components below said recess align with
said boss magnetic components to form boss detector components.
46. A medical device as claimed in claim 45 wherein said ring magnet is divided into a plurality
of discrete magnetic sections that interact with the detector boss magnetic components situated
below the mounting plate to cause the boss to be rotatable in a cogged manner between discrete
positions.

47. A medical device as claimed in claim 46 wherein said ring magnet is a continuous annular
component that is divided into a plurality of discrete magnetic sections.
48. A medical device as claimed in claim 46 wherein said ring magnet is an annular
arrangement of individual magnetic components, each representing a discrete magnetic section of
the magnetic ring.
49. A medical device as claimed in any one of claims 44 to 48 wherein at least part of said
detector magnet components align with said knob magnetic component to form a knob detector
magnetic component.
50. A medical device as claimed in claim 49 wherein said knob is depressible inwards towards
the body of said medical device from a rest position, said depressed position being the operative
position.
51. A medical device as claimed in claim 50 wherein said knob is biased toward said rest
position by a spring component that is in a compressed form and located between an outer
surface of said recess and an inwards-facing surface of said knob.
52. A medical device as claimed in claim 51 wherein said knob, said knob fastener and said
recess fastener are arranged and adapted to retain said control knob in place within said recess and
said control knob is adapted to sandwich said boss between said recess and the outer part of said
control knob to hold said boss in position.
53. A medical device as claimed in claim 52 wherein said recess fastener comprises co-
operating sprung fastening clips extending outwardly from said recess and said knob fastener
comprises sprung fastening clips extending from the inner surface of said control knob, said
fastening clips on said recess and said control knob mutually engaging to secure said knob in
posidon, said boss sandwiched between said control knob and said recess.
54. A medical device as claimed in claim 53 wherein said side of said medical device is formed
as a faceplate, fitted to said medical device in use and adapted to substantially cover the front face
of said medical device, said faceplate including a recess into which said control knob locates in
use.
55. A medical device as claimed in claim 54 wherein said front face of said medical device
includes an aperture into which said recess locates in use.
56. A control system for an integrated assisted breathing and humidifier unit, said control
system comprising;

a controller including controller memory, said controller controlling the operation of said
integrated assisted breathing and humidifier unit;
a display panel controlled by said controller; and
a user options selector, said controller responsive to changes in said options selector,
said options selector both rotatable about an axis to a number of discrete positions, and
movable along said axis of rotation in both directions from a neutral position,
said opdons selected from one or more of the group including, output power, off, heater
power level, and fan speed, said options limited by factor}' programmed limits,
said user options selector a control knob as claimed in any one of claims 42 to 52.
57. A control system as claimed in claim 56 wherein said display panel is an LCD.display,
including a plurality of user option indicators, each option indicator indicative of a user selectable
option and said plurality of indicators forming a ring.
58. A control system as claimed in claim 57 wherein each user selectable option indicator is
selectable by rotating said control knob until the appropriate option indicator is selected, and
wherein said controller indicates, the currently selected option indicator by lighting the indicator
associated with the currently selected option, said indicated user option chosen by moving said
control knob along said axis of rotation, said chosen options parameters altered by rotating said
control knob.
59. A control system as claimed in claim 58 wherein said option parameters are displayed on
said display panel, said controller altering said display in response to the rotation of said control
knob.
60. A control system as claimed in claim 59 wherein a chosen option may be exited from by
moving said control knob along said axis of rotation.
61. A control system as claimed in claim 60 wherein said controller controls the operation of
said integrated assisted breathing and humidifier unit in accordance with user set option
parameters, said controller storing said user set option parameters.
62. A control system as claimed in claim 61 wherein at least one of said options to be chosen
requires said control knob to be held in a position along said axis of rotation for a period of time.
63. A control system as claimed in claim 62 wherein said option is a shut down option, and
said control knob is required to be held in position for substantially in the region of five seconds.

64. A carry case for an integrated blower/humidification system of the type that uses a top
filling humidifier chamber with a separate lid, comprising;
an upper half and a lower half, said halves formed from a rigid material and pivotably
connected by a hinge mechanism so that said upper and lower halves can be rotated relative to
one another between a fully closed position where said upper and lower halves enclose an internal
volume, and an open position where said user can access the inside of said carry case to add or
remove items,
at least said lower half of said carry case including padding having at least one pocket
shaped'and adapted to partially enclose said integrated blower/humidification system and hold
said system in position when said system is located in said carry case,
said lower half having a flat external portion adapted to act as a side base,
said upper half including a protrusion extending from the inner surface of said upper half,
sized and aligned so that when said integrated blower/humidification system is in position within
said case, said upper half and said lower half cannot be rotated into said fully closed position while
said humidifier chamber lid is in position on said chamber.
65. A carry case as claimed in claim 64 wherein one end of said carry case is flattened to act as
an end base so that said carry case can be stood upright in use, the opposite end of said case from
said end base having the appearance of a rounded point when said case is closed, and including a
handle portion adapted to allow a user to carry said case, said packaging further including a
separate pocket adapted to hold said humidifier chamber lid.
66. A carry case as claimed in claim 65 wherein said carry case includes at least one strap.
67. A carry case for a respiratory humidification system which in use provides heated
humidified air to a user who requires a supply of heated humidified air for medical purposes, said
system of the type that includes a blower and a humidifier chamber that rigidly mate in use, said
carry case comprising;
an upper half and a lower half, said halves formed from a rigid material and pivotably
connected by a hinge mechanism so that said upper and lower halves can be rotated relative to
one another between a fully closed position where said upper and lower halves enclose an internal
volume, and an open position where said user can access the inside of said carry case to add or
remove items,

at least said lower half of said carry case including padding that has at least a first pocket
and a second pocket, said first pocket shaped and adapted to at least partially enclose at least said
blower and hold said blower in position when said blower is located in said carry case,
said second pocket adapted to at least partially enclose said humidifier chamber and hold
said blower in position when said chamber is located in said carry case, said upper half including a
protrusion extending from the inner surface of said upper half, sized and aligned so that said
upper half and said lower half cannot be rotated into said fully closed position while said
humidifier chamber and said blower are mated.
68. A carry case as claimed in claim 67 wherein said lower half has a flat external portion
adapted to act as a side base, and one end of said carry case is flattened to act as an end base so
that said carry case can be stood upright in use, the opposite end of said case from said end base
having the appearance of a rounded point when said case is closed, and including a handle portion
adapted to allow a user to carry said case.
69. A carry case as claimed in claim 68 wherein said carry case includes at least one strap.

A blower unit for use as part of an integrated
blower/humidification system is described. The blower unit has an outer casing, which encloses and forms part of the blower unit, the casing including an air inlet vent. The blower unit further includes a humidifier compartment for receiving a humidifier unit with a separate gases inlet and outlet, the compartment having a
heater base for heating the contents of the humidifier unit. The compartment also has a blower inlet port which aligns with the
humidifier unit inlet in use, the blower providing a gases path through the casing between the inlet vent and the inlet port. The
blower unit also includes a fan for providing a pressurised gases stream along the gases path, and a power supply unit for powering the fan. The gases path is routed over the power supply unit in order to provide a cooling air flow.