This invention relates to an attachment for a hand held appliance, in particular an
attachment for a hairdryer and an appliance, particularly a hairdryer comprising such an
attachment.
Blowers and in particular hot air blowers are used for a variety of applications such as
drying substances such as paint or hair and cleaning or stripping surface layers.
Generally, a motor and fan are provided which draw fluid into a body; the fluid may be
heated prior to exiting the body. The motor is susceptible to damage from foreign
objects such as dirt or hair so conventionally a filter is provided at the fluid intake end
of the blower. Conventionally such appliances are provided with a nozzle which can be
attached and detached from the appliance and changes the shape and velocity of fluid
flow that exits the appliance. Such nozzles can be used to focus the outflow of the
appliance or to diffuse the outflow depending on the requirements of the user at that
time.
According to a first aspect, the invention provides a hairdryer comprising a handle; a
body comprising a fluid outlet and a primary fluid outlet; a fan unit for generating fluid
flow through the hairdryer, the hairdryer comprising a fluid flow path extending from a
fluid inlet through which a fluid flow enters the hairdryer to the fluid outlet, and a
primary fluid flow path extending from a primary fluid inlet to the primary fluid outlet;
a heater for heating the primary fluid flow drawn through the primary fluid inlet; and a
nozzle attachable to the body, the nozzle comprising a nozzle fluid inlet for receiving
the primary fluid flow from the primary fluid outlet, and a nozzle fluid outlet for
emitting the primary fluid flow, and wherein the nozzle is configured to inhibit the
emission of the fluid flow from the fluid outlet.
The hairdryer has a primary flow which is that processed by and drawn into the
appliance by the fan unit and a fluid flow which is entrained by the primary, processed
flow. Thus the fluid flow through the hairdryer is amplified by the entrained flow.
The primary fluid flow path starts at a primary fluid inlet into the hairdryer i.e. a
primary fluid inlet through which a primary fluid flow enters the hairdryer.
Preferably, the nozzle is configured to inhibit the generation of the fluid flow.
It is preferred that the nozzle comprises means for inhibiting the flow of fluid along the
fluid flow path to the fluid outlet.
Preferably, the means for inhibiting the flow of fluid along the flow path to the fluid
outlet comprises a barrier which is located within the fluid flow path when the nozzle is
attached to the hairdryer.
It is preferred that the barrier is located an end of the nozzle.
Preferably, the barrier is substantially orthogonal to the longitudinal axis of the nozzle.
Alternatively, the barrier is inclined to the longitudinal axis of the nozzle.
It is preferred that the primary fluid outlet is configured to emit the primary fluid flow
into the fluid flow path, and wherein the nozzle comprises a first end which is insertable
into the fluid flow path through the fluid outlet, and a second end remote from the first
end, and wherein the nozzle fluid inlet is located between the first end and the second
end of the nozzle.
Preferably, wherein the nozzle fluid inlet comprises at least one aperture extending at
least partially about the longitudinal axis of the nozzle. It is preferred that the nozzle
fluid inlet comprises a plurality of apertures extending circumferentially about the
longitudinal axis of the nozzle.
Preferably, the at least one aperture has a length extending in the direction of the
longitudinal axis of the nozzle, and wherein the length of said at least one aperture
varies about the longitudinal axis of the nozzle.
It is preferred that the nozzle comprises a side wall between the first end and the second
end of the nozzle, and wherein a portion of the side wall which is located between the
first end and the second end of the nozzle at least partially defines the nozzle fluid inlet.
Preferably, the side wall is tubular in shape. It is preferred that the nozzle fluid inlet is
formed in the side wall.
Preferably, the side wall extends about an inner wall, and wherein the nozzle fluid inlet
is located between the walls of the nozzle. It is preferred that the inner wall is tubular in
shape.
Preferably, the inner wall extends from the first end to the second end. It is preferred
that the second end of the nozzle comprises the nozzle fluid outlet.
It is preferred that the nozzle fluid outlet is located between the first end and the second
end of the nozzle.
According to a second aspect, the invention provides a nozzle for a hairdryer
comprising a handle; a body comprising a fluid outlet and a primary fluid outlet; a fan
unit for generating fluid flow through the hairdryer, a fluid flow path extending from a
fluid inlet through which a fluid flow enters the hairdryer to the fluid outlet, and a
primary fluid flow path extending from a primary fluid inlet to the primary fluid outlet;
and a heater for heating the primary fluid flow drawn through the primary fluid inlet;
wherein the nozzle is attachable to the body, the nozzle comprising a nozzle
fluid inlet for receiving the primary fluid flow from the primary fluid outlet, and a
nozzle fluid outlet for emitting the primary fluid flow, and wherein the nozzle is
configured to inhibit the emission of the fluid flow from the fluid outlet.
The primary fluid flow path starts at a primary fluid inlet into the hairdryer i.e. a
primary fluid inlet through which a primary fluid flow enters the hairdryer.
Preferably, the nozzle is configured to inhibit the generation of the fluid flow.
It is preferred that the nozzle comprises means for inhibiting the flow of fluid along the
fluid flow path to the fluid outlet of the hairdryer.
Preferably, the means for inhibiting the flow of fluid along the flow path to the fluid
outlet comprises a barrier which is located within the fluid flow path when the nozzle is
attached to the hairdryer.
It is preferred that the barrier is located an end of the nozzle.
Preferably, the barrier is substantially orthogonal to the longitudinal axis of the nozzle.
Alternatively, the barrier is inclined to the longitudinal axis of the nozzle.
Preferably, the nozzle comprises a first end which is insertable into the fluid flow path
through the fluid outlet, and a second end remote from the first end, and wherein the
nozzle fluid inlet is located between the first end and the second end of the nozzle.
It is preferred that the nozzle fluid inlet comprises at least one aperture extending at
least partially about the longitudinal axis of the nozzle.
Preferably, the nozzle fluid inlet comprises a plurality of apertures extending
circumferentially about the longitudinal axis of the nozzle.
It is preferred that the at least one aperture has a length extending in the direction of the
longitudinal axis of the nozzle, and wherein the length of said at least one aperture
varies about the longitudinal axis of the nozzle.
Preferably, the nozzle comprises a side wall between the first end and the second end of
the nozzle, and wherein a portion of the side wall which is located between the first end
and the second end of the nozzle at least partially defines the nozzle fluid inlet.
It is preferred that the side wall is tubular in shape.
Preferably, the nozzle fluid inlet is formed in the side wall.
It is preferred that the side wall extends about an inner wall, and wherein the nozzle
fluid inlet is located between the walls of the nozzle.
Preferably, the inner wall is tubular in shape. It is preferred that the inner wall extends
from the first end to the second end.
It is preferred that the second end of the nozzle comprises the nozzle fluid outlet.
Preferably, the nozzle fluid outlet is located between the first end and the second end of
the nozzle.
The invention will now be described by way of example and with reference to the
accompanying drawings, of which:
Figures l a to If show various representations of a single flow path nozzle according to
the invention;
Figures 2a to 2c show various representations of a single flow path nozzle attached to a
hairdryer;
Figures 3a to 3d show a nozzle with an end valve;
Figure 4a shows an alternate single flow path nozzle attached to a hairdryer;
Figures 4b to 4g show an alternate single flow path nozzle;
Figures 5a to 5e show a further single flow path nozzle;
Figures 6a to 6c show another single flow path nozzle with a hairdryer;
Figures 7a to 7c show a nozzle and hairdryer having two inlets into a single flow path;
Figures 8a to 8d show an alternate two outlet arrangement;
Figures 9a to 9d show a further nozzle and hairdryer combination;
Figures 10a to lOg show yet another single flow path nozzle and hairdryer;
Figures lOh and lOi show the hairdryer without a nozzle; and
Figures lOj to 10m show a further attachment with a hairdryer.
Figures l a to If show a nozzle 100 comprising a generally tubular body 110 with a
longitudinal axis A-A extending along the length of the body, having a fluid inlet 120
through a wall 112 of the body 110 and a fluid outlet 130 downstream of the fluid inlet
120. The fluid inlet 120 has a length that extends in the direction of the longitudinal
axis A-A of the nozzle and is located between a first or upstream end 100a and a second
or downstream end 100b of the nozzle 100.
In this example, the fluid outlet 130 is slot shaped and the length of the slot B-B is
greater than the diameter C-C of the body 110. In this example, the fluid inlet 120
comprises a number of discrete apertures 120a separated by reinforcing struts 120b.
The apertures 120a extend circumferentially about the longitudinal axis of the nozzle
100.
In use, fluid flows into the fluid inlet 120 along the length of the body 110 along fluid
flow path 160 and out through the fluid outlet 130. The upstream end 100a of the
nozzle 100 is closed by an end wall 140 thus fluid can only enter the nozzle 100 via the
fluid inlet 120 when in use.
Figures 2a to 2c show the nozzle 100 attached to a hairdryer 200. The nozzle 100 is
inserted into the downstream end 200b of the hairdryer until a stop 210 is reached. In
this position, the fluid inlet 120 of the nozzle 100 is in fluid communication with a
primary fluid outlet 230 of the hairdryer 200. The nozzle is an attachment for adjusting
at least one parameter of the fluid flow emitted from the hairdryer and the downstream
end 100b of the nozzle protrudes from the downstream end 200b of the hairdryer 200.
The hairdryer 200 has a handle 204, 206 and a body 202 which comprises a duct 282,
284. A primary fluid flow path 260 starts at a primary inlet 220 which in this example
is located at the upstream end 200a of the hairdryer i.e. at the distal end of the hairdryer
from the fluid outlet 200b. Fluid is drawn into the primary fluid inlet 220 by a fan unit
250, fluid flows along primary fluid flow path 260 located on the inside of the outer
body 202 of the hairdryer between the outer body 202 and the duct 282, along a first
handle portion 204 to the fan unit 250.
The fan unit 250 includes a fan and a motor. The fluid is drawn through the fan unit
250, along a second handle portion 206 and returns to the body 202 of the hairdryer in
an inner tier 260a of the body. The inner tier 260a of the body 202 is nested within the
primary fluid flow path 260 between the primary fluid flow path 260 and the duct 282
and includes a heater 208. The heater 208 is annular and heats the fluid that flows
through the inner tier 260a directly. Downstream of the heater 208, fluid exits the
primary fluid flow path at the primary outlet 230.
With the nozzle 100 attached to the hairdryer 200, the primary outlet 230 is in fluid
communication with the fluid inlet 120 of the nozzle 100. Fluid that flows out of the
primary outlet 230 flows along the body 110 of the nozzle 100 to the nozzle outlet 130.
The hairdryer 200 has a second fluid flow path 280. This second fluid flow path 280
flows from a second inlet 270 along the length of the body 202 of the hairdryer through
duct 282 to a second outlet 290 outlet where, when there is no nozzle attached to the
hairdryer, fluid flowing through the second fluid flow path 280 mixes with the primary
fluid at the primary fluid outlet 230. This mixed flow continues along duct 284 to the
fluid outlet 200b of the hairdryer. The fluid that flows through the second fluid flow
path 280 is not processed by the fan unit 250; it is entrained by the primary fluid flow
through the primary fluid flow path 260 when the fan unit is switched on.
The second fluid flow path 280 can be considered to flow along a tube defined by an
upstream duct 282 and a downstream duct 284 where the primary outlet 230 is an
aperture in the tube between the ducts 282 and 284. The nozzle is partially inserted into
the tube defined by the ducts 284, 282. In this example the nozzle 100 is slidably
inserted into hairdryer outlet 200b along downstream duct 284 past the aperture or
primary fluid outlet 230 into the upstream duct 282. The nozzle 100 is retained in the
duct 282, 284 by friction. In this example, the friction is provided between stop 210 and
the duct 284 of the hairdryer.
Nozzle 100 is a single flow path nozzle and only fluid that has been processed by the
fan unit 250 from the primary fluid flow path 260 flows through the nozzle 100. The
end wall 140 of the nozzle 100 is a barrier that blocks the second fluid flow path 280
and thereby prevents entrainment into the second fluid flow path when the nozzle is
properly attached to the hairdryer. The nozzle 100 prevents emission of the entrained
fluid and inhibits the generation of the entrained fluid.
As an alternative, the nozzle could extend into downstream duct 284 of the hairdryer
200 but not as far as the primary fluid outlet 230. In this example, fluid from the
primary fluid flow path 260 would mix with entrained fluid from the second fluid flow
path 280 at the primary fluid outlet 230 and the mixed flow would enter the nozzle at
the upstream end of the nozzle and continue to the fluid outlet 130 of the nozzle
producing a combined fluid flow at the nozzle outlet.
It is advantageous that the end wall 140 of the nozzle 100 comprises a valve. This
assists if the nozzle 100 is inserted into the hairdryer whilst the hairdryer is switch on.
The valve is designed to open and let the full fluid flow through it this is for example
around 22 1/s.
Referring now to Figures 3a to 3d, the operation of a valve in the nozzle will now be
described. When the nozzle 100 is initially inserted into the outlet end 200b of a
hairdryer 200 as is shown in Figure 3a, the valve 150 in the upstream end wall 140 of
the nozzle 100 opens. The valve 150 is attached to a central strut 152 of the end wall
140 and when the force of the fluid flow is high enough the valve 150 folds into the
nozzle 100 to make an opening 154, for example an annular opening, in the end wall
140 of the nozzle 100. The valve 150 is pushed downstream by the force of the fluid
flowing into the nozzle 100.
Once the inlet 120 is partially aligned with the primary outlet 230 of the hairdryer 200,
some of the primary flow will flow through the inlet 120 which results in a reduction in
the pressure at the valve 150. Once at least the majority of the primary flow goes
through the inlet 120, the valve 150 will shut as is shown in Figure 3c. When the valve
150 is shut the end wall 140 of the nozzle is blocked so fluid cannot flow through the
second fluid flow path 280. Thus the only flow is from the primary outlet 230 of
primary fluid flow path 260 into the inlet 120 of the nozzle.
Nozzle 100 is a hot styling nozzle. Although around only half of the normal flow
through the hairdryer will flow through the nozzle to the outlet 130 the velocity of the
flow is increased by the shape of the nozzle so a user will feel a similar force to that of
normal flow. Normal flow is the total flow through the hairdryer without an attachment
i.e. the primary flow plus the second or entrained flow. The shape of the nozzle outlet
130 reduces the cross sectional area compared with the hairdryer outlet 200b which
increases the velocity of the flow.
Whilst the hairdryer shown has the primary fluid flow path flowing through the handles
of the hairdryer, this is not required. The primary fluid flow path can alternatively flow
from the primary inlet 220 along the body 202 through the heater to the primary fluid
outlet 230 and thence into the nozzle.
Figures 6a to 6f show a nozzle 800 and a nozzle 800 attached to a hairdryer 200. In this
embodiment, components illustrated and described with respect to Figures 2a to 2c have
like reference numbers. The nozzle is similar to nozzle 100 but instead of a valve 150,
this nozzle 800 is provided with a slanted upstream end 800a and fluid inlet 820 i.e. the
fluid inlet 820 has a length that extends in the direction of the longitudinal axis of the
nozzle 800 and varies about the longitudinal axis of the nozzle. The fluid inlet 820 is
defined by a side wall 822 of the body 810 of the nozzle 800 where the side wall 822 is
substantially orthogonal to the wall 812 of the body and the longitudinal axis A-A of the
nozzle 800.
When the nozzle 800 is inserted into the outlet end 200b of a hairdryer 200, the fluid
inlet 820 gradually aligns with the primary fluid outlet 230 of the hairdryer (Figure 6f).
When the nozzle 800 is fully inserted as is shown in Figure l id, the whole of the
annular primary fluid outlet 230 is in fluid communication with the nozzle inlet 820.
There will be an initial resistance to the insertion of the nozzle 800 when the hairdryer is
switched on as there will be both primary and second fluid flowing through the
hairdryer however, the entrainment effect will gradually reduce as the hairdryer outlet
end 200b is blocked by the slanted nozzle inlet end 800a until the hairdryer outlet end
800b is completely blocked. At this point, primary flow from the primary fluid outlet
230 that cannot enter the fluid inlet 820 is redirected down a second fluid flow path 280
towards the rear or upstream end 200a of the hairdryer. So, when the nozzle is initially
inserted the primary flow cannot exit the downstream end 800b of the nozzle but can
flow in a reverse direction along the second fluid flow path 280. This feature provides
protection from the heater overheating during the nozzle insertion process as there will
always be some fluid flowing through the primary fluid flow path.
Figures 4a to 4g show an alternate single flow path nozzle 600 having a generally
tubular body 610, a first or upstream end 600a and a second or downstream end 600b.
There is a fluid inlet 620 in an outer wall 612 of the body 610 between the first end
600a and the second end 600b of the nozzle 600 and a fluid outlet 630 downstream of
the fluid inlet 620. In this example, the fluid outlet 630 is ring shaped or annular and is
formed by an inner wall 614 of the nozzle 600 and the outer wall 612.
The fluid inlet 620 is an opening in the outer wall 612 of the nozzle and is defined by an
aperture formed from a slanted edge 622b of the outer wall and a curved side wall 622
provided at the upstream end of the fluid inlet which connects the outer wall 612 and the
inner wall 614. The slanted edge of the outer wall is slanted in the direction of fluid
flow to reduce turbulence and pressure losses as the primary flow enters the nozzle.
The outer wall 612 surrounds inner wall 614 and together walls 612, 614 define a fluid
flow path 660 through the generally tubular body 610 from the inlet 620 to the outlet
630. In the vicinity of the outlet 630, the inner wall curves outwards 614b and increases
in diameter causing a reduction in the cross section of the fluid flow path at the outlet
630. The inner wall 614 continues beyond the outlet 630 and the end of the outer wall
612 of the nozzle 600 to a downstream nozzle end 600b. The inner wall 614b is convex
and is a Coanda surface i.e. it causes fluid that flows through the fluid flow path 660 to
hug the surface of the inner wall 614b as it curves forming an annular flow at the outlet
630 and downstream nozzle end 600b. In addition the Coanda surface 614 is arranged
so a primary fluid flow exiting the outlet 630 is amplified by the Coanda effect.
The hairdryer achieves the output and cooling effect described above with a nozzle
which includes a Coanda surface to provide an amplifying region utilising the Coanda
effect. A Coanda surface is a known type of surface over which fluid flow exiting an
output orifice close to the surface exhibits the Coanda effect. The fluid tends to flow
over the surface closely, almost 'clinging to' or 'hugging' the surface. The Coanda effect
is already a proven, well documented method of entrainment whereby a primary air
flow is directed over the Coanda surface. A description of the features of a Coanda
surface, and the effect of fluid flow over a Coanda surface, can be found in articles such
as Reba, Scientific American, Volume 214, June 1963 pages 84 to 92.
Advantageously, the assembly results in the entrainment of air surrounding the mouth of
the nozzle such that the primary air flow is amplified by at least 15%, whilst a smooth
overall output is maintained
By encouraging the fluid at the outlet 630 to flow along 616 the curved surface 614b of
the inner wall to the downstream nozzle end 600b, fluid is entrained 618 from outside
the hairdryer 200 (Figure 4c) by the Coanda effect. This action of entrainment increases
the flow of air at the downstream nozzle end 600b, thus the volume of fluid flowing at
the downstream nozzle end 600b is magnified by the entrainment above what is
processed by the hairdryer 200 through a fan unit 250 and heater 208.
When the nozzle 600 is attached to a hairdryer 200 as shown in Figure 4a, the fluid inlet
620 aligns with a primary fluid outlet 230 of the hairdryer. Hairdryer 200 has a second
fluid flow path 280 through a central duct 282 but this is blocked by the nozzle 600. In
the example shown in Figure 2a, nozzle 100 blocked the second fluid flow path 280 at
the upstream end 100a of the nozzle. In this example, the nozzle 600 uses an upstream
continuation of curved wall 614b which curves inwards to form a rounded end 616
which blocks the second fluid flow path.
In order to seal the nozzle fluid flow path 660 with respect to the primary fluid outlet
230, the outer wall 612 of the nozzle is provided with a collar 612a. The collar 612a is
upstanding from the outer wall 612 so has a larger diameter than the outer wall and is
designed to fit with ducting 282 within the hairdryer 200. The collar 612a is upstream
of the fluid inlet 620 of the nozzle 600. A second collar 612b is ideally also provided
downstream of the fluid inlet 620 and prevents fluid from the primary outlet 230 of the
hairdryer flowing between the outer wall 612 of the nozzle and the hairdryer outlet
200b.
Figures 5a to 5e show a further single flow path nozzle 10 which is similar to the one
described with respect to Figure 8 . In this nozzle a fluid flow path 60 is provided from
an inlet 20 to an outlet 30. The inlet 20 is through an outer wall 12 of a generally
tubular body 14 of the nozzle 10 between a first or upstream end 10a and a second or
downstream end 10b of the nozzle 10. The outlet 30 is a slit formed between the outer
wall 12 and an inner wall 32 of the nozzle.
The inner wall 32 is convex and formed by a bung 34 which is located in the
downstream end 12b of the outer wall 12. Fluid that flows through the fluid flow path
60 is funnelled by an upstream end 34a of the bung 34 towards the outlet 30. As the
inner wall 32 is convex, fluid that flows out of the outlet 30 is drawn to the surface 32
by the Coanda effect and this entrains fluid 18 from the environment around the nozzle
10.
The shape of the bung 34 at the downstream end 34b is generally rectangular so the
fluid exits the nozzle in a generally rectangular profile.
The rear or upstream end 10a of the nozzle has a cone shaped bung 70 so when the
nozzle 10 is used in conjunction with hairdryer 200 (not shown), fluid from the second
fluid flow path 280 is blocked by the cone shaped bung 70.
Figures 7a to 7c show a nozzle and hairdryer combination where the nozzle 1100 has a
generally tubular body 1103 with a longitudinal axis D-D extending along the length of
the body and having a first inlet 1102 and a second inlet 1104 into the fluid flow path
1106 of the nozzle 1100. The hairdryer 1120 has a corresponding primary outlet 1122
and second primary outlet 1124 which provide fluid communication with the first inlet
1102 and the second inlet 1104 respectively. This arrangement means that the primary
flow through the primary fluid flow path 1126 of the hairdryer has two outlet regions.
The use of a nozzle 1100 on a hairdryer 1120 introduces a restriction to the flow
through the hairdryer resulting in a drop in output by the hairdryer of up to around 41/s.
By introducing a second primary outlet 1124 for the primary flow the drop in output is
mitigated.
The second inlet 1104 is similar to first inlet 1102 in that is extends in the direction of
the longitudinal axis of the nozzle and radially round through outer wall 1110 of the
generally tubular body 1103 of the nozzle 1100. The second inlet 1104 consists of a
number of discrete apertures 1104a separated by reinforcing struts 1104b.
Referring to Figure 7a, which shows a portion of a hairdryer having a primary fluid
outlet comprising first 1122 and second 1124 primary outlets when there is no nozzle
attached to the hairdryer 1120, the second primary outlet 1124 is closed as it is not
required to increase flow through the primary fluid flow path 1126 of the hairdryer
1120. A closure 1130 is provided which occludes, blocks, covers or restricts the second
primary outlet 1124. The closure 1130 is biased into the closed position by a spring
1132, in this example, which pushes against the closure 1124 to occlude the second
primary outlet 1124. The first 1122 and second 1124 primary outlets both comprise
apertures and are spaced apart along the longitudinal axis D-D of the nozzle 1100.
Referring now to Figure 7c, the nozzle 1100 is provided with a lip 1108 which is
upstanding from the generally tubular wall 1101 of the nozzle. The lip 1108 can be
continuous or discontinuous around the perimeter of the generally tubular outer wall
1105 of the body 1103 of the nozzle 1100 and is of sufficient depth or height upstanding
from the wall 1105 to firstly engage with the closure 1130 and secondly to allow the
nozzle to be inserted up to the point of engagement of the lip 1108 with the closure
1130 without snagging of the nozzle 1100.
The lip in this example is formed from an O-ring which is held in a recess formed in the
body 1103 of the nozzle. Alternatives will be apparent to the skilled person and
include, but are not limited to an integral moulded lip, a plastic/hard rubber ring, a
living hinge, an overmoulded lip and a push fit arrangement.
The closure 1130 is ring shaped and has an S-shaped profile. Central to the ring is an
aperture 1126 to enable fluid flowing through the primary fluid flow path 1126 of the
hairdryer to exit the downstream end 1120b of the hairdryer from the first primary fluid
outlet 1122 of the hairdryer. A first end 1125 of the S-shaped profile of the closure
1130 engages with one end of spring 1132 and provides the means by which the closure
1130 is biased into an occluded or closed position. A second end 1127 of the S-shaped
profile protrudes into the fluid flow path 1129 of the hairdryer between the primary
outlet 1122 and the downstream end 1120b of the hairdryer. This second end 1127 of
the closure 1130 engages with the lip 1108 of the nozzle 1100 when the nozzle is
inserted far enough into the downstream end 1120b of the hairdryer 1120 (see Figure
7b) and as the nozzle is inserted past the point of engagement, the closure 1130 is
pushed against the action of the spring 1132 and slides, opening the second primary
outlet 1124 to allow fluid flowing in the primary fluid flow path 1126 to exit via either
the first primary outlet 1122 or the second primary outlet 1124 thus mitigating any
restriction on fluid flow through the hairdryer from the use of a nozzle.
In order to prevent egress of fluid from the primary fluid flow path 1126 from the
hairdryer outlet 1120b around the outside of the nozzle 1100. The outer wall 1103 is
provided with an upstanding collar 1110 that extends about the outer wall 1103 and
seals the nozzle with respect to the hairdryer outlet 1120. The collar 1110 additionally
provides a point of friction between the nozzle and the hairdryer that retains the nozzle
within the hairdryer.
The nozzle 1100 has a downstream end 110b where fluid is output through a nozzle
outlet 1112 and an upstream end 1100a. In one embodiment the upstream end 1100b of
the nozzle comprises an end wall 1114. In this embodiment, the primary flow from the
hairdryer is the only flow that is output from the nozzle outlet 1112.
Figures 8a to 8d show a different arrangement. In this example, the second primary
outlet 1174 from the primary fluid flow path 1176 is in an end wall 1160 of the
hairdryer 1150 rather than through an internal wall.
Referring now to Figure 8a, the hairdryer has a generally tubular body 1152 having an
inner wall 1154a 1154b and an outer or external wall 1156. At the downstream end
1150b of the hairdryer an end wall 1160, 1180 is provided between the inner 1154b and
outer 1156 wall. The end wall is orthogonal to a longitudinal axis E-E of the body 1152
and includes a fixed portion 1160 and a moveable portion or closure 1180. The closure
1180 is annular and is biased by a spring 1182 to be substantially flush with the fixed
portion of the end wall 1160. When a nozzle is inserted into the hairdryer 1150, the
closure 1180 is pushed against the spring 1182, causing the spring to compress and open
the second primary outlet 1174. In this example, the closure 1180 is adjacent to the
inner wall 1154b of the hairdryer however the closure could be located anywhere
between the inner and outer walls. In addition, the closure need not be continuous
around the end wall.
Referring now to Figure 8d, the nozzle 1190 has a generally tubular body 1192 having
an outer wall 1194. A first inlet 1196 is provided in the outer wall 1194 between an
upstream or first end 1190a and a downstream or second end 1190b of the nozzle but
towards the upstream end 1190a of the nozzle. This first inlet 1196 is in fluid
communication with a first primary outlet 1172 of the hairdryer provided in the inner
wall 1154 of the body of the hairdryer and a fluid flow path 1197 is provided through
the nozzle from the first inlet 1196 through the body 1192 of the nozzle to a nozzle
outlet 1198 at the downstream end 1190b of the nozzle. The outer wall 1194 of the
nozzle is designed to be insertable into the outlet end 1150b of the hairdryer. At the
downstream end 1194b of the outer wall 1194 a hook shaped lip 1193 is provided.
When the nozzle 1190 is inserted in the hairdryer, the hooked shaped lip 1193 covers
the end of inner wall 1154b of the hairdryer and engages with closure 1180 pushing it
against the action of the spring 1182. In order to provide a second fluid flow path 1184
from the second opening 1174 to the downstream end 1190b of the nozzle, a collar 1195
is provided on the nozzle. When the nozzle is inserted into the hairdryer, the collar
1195 fits over the outer wall 1156 of the body 1152 of the hairdryer and forms together
with the fixed portion of the end wall 1160 and the hook shaped lip 1193 a second fluid
inlet 1184 for the nozzle which combines with fluid from the first inlet 1196 in the fluid
flow path 1197 within the nozzle.
The nozzle 1190 is inserted as shown in Figures 8b and 8c; the lip 1193 engages with
the closure 1180 and forces the closure back against the action of the spring 1182
opening the second primary outlet 1174.
Figures 9a to 9d show an alternate arrangement for mitigating flow restriction when a
nozzle 1200 is used on a hairdryer 1252. In this example, insertion of a nozzle 1200
results in the primary fluid outlet 1250 of the hairdryer 1252 increasing in size.
The nozzle 1200 has a generally tubular body 1202 with a longitudinal axis F-F
extending along the length of the body 1202. A fluid inlet 1208 comprising a number of
apertures 1210 separated by struts 1212 has a length that extends in the direction of the
longitudinal axis F-F of the nozzle 1200 and is located between a first or upstream end
1200a and a second or downstream end 1200b of the nozzle 1200 in an outer wall 1204
of the body 1202.
The hairdryer 1252 has a generally tubular body having an inner wall 1254a, 1254b, an
outer wall 1256 and a primary fluid flow path 1258 provided therebetween. The
primary fluid flow path 1258 flows from a primary inlet 1220 to a primary outlet 1250
provided as an aperture between two sections of the inner wall 1254a, 1254b and then
through a central bore 1260 in the body of the hairdryer 1252 to a hairdryer outlet 1262.
The primary outlet 1250 is formed from a fixed surface 1270 attached to the
downstream section of inner wall 1254b and a moveable surface 1272 which is
connected to an upstream section of the inner wall 1254a. In order that the primary
outlet 1250 can be opened, a moveable portion 1254aa of the upstream inner wall 1254a
is slidably moveable against the direction of fluid flow at the primary fluid outlet 1250
towards the upstream end 1252a of the hairdryer 1252. The upstream section of the
inner wall 1254a and the moveable portion 1254aa form a lap joint 1282 (Figure 14d)
which is biased apart by a spring 1280 (Figures 9a and 9b). The moveable portion
1254aa has an internal surface which describes a duct 1262 within the hairdryer and is
provided with a rim or lip 1264 which is upstanding from the duct 1262 and extends
radially into the duct 1262. When a nozzle 1200 is inserted into the outlet 1262 of the
hairdryer, the upstream end 1200a of the outer wall 1204 of the nozzle engages with the
rim or lip 1262 on the moveable portion 1254aa and pushes the moveable portion
1254aa against the biasing action of the spring 1280 so the moveable portion 1254aa
slides towards the upstream inner wall 1254a and opens the primary fluid outlet 1250
(Figures 9c and 9d).
When the nozzle 1200 is subsequently removed, the moveable portion 1254aa slides
back towards the downstream end 1252b of the hairdryer 1252 causing the primary
outlet 1250 to reduce back to its' original size.
Figures 10a, 10b, lOh to 10k all show a hairdryer 670 having a primary fluid flow path
671 which is processed by a fan unit 672 and a heater 673 second fluid flow path 680
which comprises fluid that has been entrained into the hairdryer by the action of the fan
unit 672 drawing fluid into the primary fluid flow path 671.
Referring in particular to Figures lOh and lOi, a primary fluid flow is drawn into the
primary fluid flow path 671 at a primary inlet 674 and flows along a first handle 676
though a fan unit 672, along a second handle 677 through a heater 673 and out of a
primary outlet 675 into a duct 678 of the hairdryer to the fluid outlet 679. A second
fluid flow path 680 is provided from a second inlet 681 at the upstream end 670a of the
hairdryer through the duct 678 to the hairdryer outlet 679. Fluid is entrained into the
second fluid flow path 680 by the action of the fan unit 672 drawing fluid into the
primary inlet 674 to the primary outlet 675 and mixes or combines with the primary
flow at the primary fluid outlet 675. The fluid that flows through the duct 678 to the
outlet 679 is a combined primary and entrained flow.
The primary fluid outlet 675 is relatively large and unrestricted. In order to encourage
entrainment into the second fluid flow path 680, an attachment 685 is provided. The
attachment 685 (Figures 101 and 10m) is inserted into the hairdryer outlet 679 and
comprises a generally tubular body 686 between a first or upstream end 685a and a
second or downstream end 685b. In order to encourage entrainment by the Coanda
effect, the attachment 685 is provided with a Coanda surface 687 at the upstream end
685a. The Coanda surface 687 is in fluid communication with the primary fluid outlet
675 when the attachment is inserted in the hairdryer 670 (Figures lOj and 10k) and
causes primary fluid to hug the Coanda surface 687 when the primary fluid flow exits
the primary fluid outlet 675 into the nozzle fluid flow path 688 and to a nozzle outlet
689. The downstream end 685b of the attachment 685 is provided with an upstanding
lip 690 which protrudes from the downstream end 670b of the hairdryer and covers the
downstream end 670b of the hairdryer. The nozzle outlet 689 is circular and has a
smaller diameter than the hairdryer outlet 679.
Referring now to Figures 10c to lOg, a second attachment 850 is provided. This second
attachment 850 is a hot styling nozzle and only provides an outlet for the primary flow
from the hairdryer 670.
The second attachment 850 has a generally tubular body 851 which defines a
longitudinal axis G-G of the attachment from a first or upstream end 850a to a second or
downstream end 850b. At the upstream end 850a, an end wall 852 is provided which is
designed to block the second fluid flow path 680 of the hairdryer 670. A fluid inlet 853
is provided in the body 851 downstream of the end wall 852 and fluid can flow from the
fluid inlet 853 along a fluid flow path 854 to a fluid outlet 855 at the downstream end
850b of the nozzle. The nozzle 850 is designed to be partially insertable into hairdryer
670 such that the fluid inlet is in fluid communication with the primary fluid outlet 675.
The portion of the nozzle that is insertable is generally tubular and is provided with an
upstanding lip of collar 856 around the body 850 which abuts the downstream end 670b
of the hairdryer when the attachment 850 is inserted properly. Downstream of the lip
856, the change of the attachment changes from generally circular to generally
rectangular to provide a focused flow from the nozzle outlet 855.
When there is no nozzle of the first type of nozzle 685 attached to the hairdryer 670, a
primary fluid flow is augmented by an entrained flow through the second fluid flow
path 680 and the total fluid output from the fluid outlet 679 is the combined value of the
primary flow and the entrained flow. The second attachment 850 only allows primary
flow from the hairdryer and blocks the entrained flow so, could suffer from a lower
velocity of fluid output at the nozzle outlet 855. However, this is mitigated as the
upstream end 855a of the nozzle 855 is designed to sit in the duct 678 of the hairdryer
670 so it does not restrict flow from the primary outlet 675. The upstream end of the
nozzle body 851 has a curved wall 857 so turbulence and pressure losses as a result of
the use of the second attachment 850 are minimised. This second nozzle 850 has the
effect of opening up the amp gap or the primary fluid outlet 675.
The lip or collar 856, 690 has the effect of not only informing the user that the nozzle or
attachment 850, 685 has been correctly inserted into the hairdryer outlet 679 but also
provides a seal against fluid from the primary fluid outlet 675 exiting external to the
nozzle or attachment 850, 685.
The nozzle is retained with respect to the hairdryer by one of a number of alternatives
which include but are not limited to a felt seal, a bump stop, an o-ring, magnets, friction
fit, a mechanical clip, snap fit or actuated snap fit.
The hairdryers are preferably provided with a filter 222 (Figures 2b and 2c) which
covers at least the primary fluid flow inlet 220 of the hairdryer. The filter 222 is
provided as is prevents ingress of dust, debris and hair into the primary fluid flow path
upstream 260 of the fan unit250 which includes a fan and a motor. These foreign
objects could damage the motor and cause premature failure of the hairdryer. The filter
222 can cover the entire intake of the hairdryer i.e. both the primary fluid flow path 260
and the second fluid flow path 280 however this is not preferred as it interferes with a
line of sight through the appliance. A line of sight through the appliance is restricted by
the use of a nozzle on the appliance.
The invention has been described in detail with respect to a nozzle for a hairdryer and a
hairdryer comprising a nozzle however, it is applicable to any appliance that draws in a
fluid and directs the outflow of that fluid from the appliance.
The appliance can be used with or without a heater; the action of the outflow of fluid at
high velocity has a drying effect.
The fluid that flows through the appliance is generally air, but may be a different
combination of gases or gas and can include additives to improve performance of the
appliance or the impact the appliance has on an object the output is directed at for
example, hair and the styling of that hair.
The invention is not limited to the detailed description given above. Variations will be
apparent to the person skilled in the art.

WE CLAIMS:-
1. A hairdryer comprising a handle; a body comprising a fluid outlet and a primary
fluid outlet; a fan unit for generating fluid flow through the hairdryer, the hairdryer
comprising a fluid flow path extending from a fluid inlet through which a fluid flow
enters the hairdryer to the fluid outlet, and a primary fluid flow path extending from a
primary fluid inlet through which a primary fluid flow enters the hairdryer to the
primary fluid outlet; a heater for heating the primary fluid flow drawn through the
primary fluid inlet; and a nozzle attachable to the body, the nozzle comprising a nozzle
fluid inlet for receiving the primary fluid flow from the primary fluid outlet, and a
nozzle fluid outlet for emitting the primary fluid flow, and wherein the nozzle is
configured to inhibit the emission of the fluid flow from the fluid outlet.
2 . A hairdryer according to claim 1, wherein the nozzle is configured to inhibit the
generation of the fluid flow.
3 . A hairdryer according to claim 1 or claim 2, wherein the nozzle comprises
means for inhibiting the flow of fluid along the fluid flow path to the fluid outlet.
4 . A hairdryer according to claim 3, wherein the means for inhibiting the flow of
fluid along the flow path to the fluid outlet comprises a barrier which is located within
the fluid flow path when the nozzle is attached to the hairdryer.
5 . A hairdryer according to claim 4, wherein the barrier is located an end of the
nozzle.
6 . A hairdryer according to claim 4 or claim 5, wherein the barrier is substantially
orthogonal to the longitudinal axis of the nozzle.
7 . A hairdryer according to claim 4 or claim 5, wherein the barrier is inclined to the
longitudinal axis of the nozzle.
8 . A hairdryer according to any preceding claim, wherein the primary fluid outlet is
configured to emit the primary fluid flow into the fluid flow path, and wherein the
nozzle comprises a first end which is insertable into the fluid flow path through the fluid
outlet, and a second end remote from the first end, and wherein the nozzle fluid inlet is
located between the first end and the second end of the nozzle.
9 . A hairdryer according to claim 8, wherein the nozzle fluid inlet comprises at
least one aperture extending at least partially about the longitudinal axis of the nozzle.
10. A hairdryer according to claim 8 or claim 9, wherein the nozzle fluid inlet
comprises a plurality of apertures extending circumferentially about the longitudinal
axis of the nozzle.
11. A hairdryer according to claim 9 or claim 10, wherein the at least one aperture
has a length extending in the direction of the longitudinal axis of the nozzle, and
wherein the length of said at least one aperture varies about the longitudinal axis of the
nozzle.
12. A hairdryer according to any of claims 8 to 11, wherein the nozzle comprises a
side wall between the first end and the second end of the nozzle, and wherein a portion
of the side wall which is located between the first end and the second end of the nozzle
at least partially defines the nozzle fluid inlet.
13. A hairdryer according to claim 12, wherein the side wall is tubular in shape.
14. A hairdryer according to claim 12 or claim 13, wherein the nozzle fluid inlet is
formed in the side wall.
15. A hairdryer according to claim 12 or claim 13, wherein the side wall extends
about an inner wall, and wherein the nozzle fluid inlet is located between the walls of
the nozzle.
16. A hairdryer according to claim 15, wherein the inner wall is tubular in shape.
17. A hairdryer according to claim 15 or claim 16, wherein the inner wall extends
from the first end to the second end.
18. A hairdryer according to any of claims 8 to 17, wherein the second end of the
nozzle comprises the nozzle fluid outlet.
19. A hairdryer according to any of claims 8 to 17, wherein the nozzle fluid outlet is
located between the first end and the second end of the nozzle.
20. A nozzle for a hairdryer comprising a handle; a body comprising a fluid outlet
and a primary fluid outlet; a fan unit for generating fluid flow through the hairdryer, a
fluid flow path extending from a fluid inlet through which a fluid flow enters the
hairdryer to the fluid outlet, and a primary fluid flow path extending from a primary
fluid inlet through which a primary fluid flow enters the hairdryer to the primary fluid
outlet; and a heater for heating the primary fluid flow drawn through the primary fluid
inlet;
wherein the nozzle is attachable to the body, the nozzle comprising a nozzle
fluid inlet for receiving the primary fluid flow from the primary fluid outlet, and a
nozzle fluid outlet for emitting the primary fluid flow, and wherein the nozzle is
configured to inhibit the emission of the fluid flow from the fluid outlet.
2 1. A nozzle according to claim 20, wherein the nozzle is configured to inhibit the
generation of the fluid flow.
22. A nozzle according to claim 20 or claim 21, comprising means for inhibiting the
flow of fluid along the fluid flow path to the fluid outlet of the hairdryer.
23. A nozzle according to claim 22, wherein the means for inhibiting the flow of
fluid along the flow path to the fluid outlet comprises a barrier which is located within
the fluid flow path when the nozzle is attached to the hairdryer.
24. A nozzle according to claim 23, wherein the barrier is located an end of the
nozzle.
25. A nozzle according to claim 23 or claim 24, wherein the barrier is substantially
orthogonal to the longitudinal axis of the nozzle.
26 A nozzle according to claim 23 or claim 24, wherein the barrier is inclined to the
longitudinal axis of the nozzle.
27. A nozzle according to any of claims 20 to 26, comprising a first end which is
insertable into the fluid flow path through the fluid outlet, and a second end remote from
the first end, and wherein the nozzle fluid inlet is located between the first end and the
second end of the nozzle.
28. A nozzle according to claim 27, wherein the nozzle fluid inlet comprises at least
one aperture extending at least partially about the longitudinal axis of the nozzle.
29. A nozzle according to claim 27 or claim 28, wherein the nozzle fluid inlet
comprises a plurality of apertures extending circumferentially about the longitudinal
axis of the nozzle.
30. A nozzle according to claim 28 or claim 29, wherein the at least one aperture has
a length extending in the direction of the longitudinal axis of the nozzle, and wherein
the length of said at least one aperture varies about the longitudinal axis of the nozzle.
31. A nozzle according to any of claims 27 to 30, comprising a side wall between
the first end and the second end of the nozzle, and wherein a portion of the side wall
which is located between the first end and the second end of the nozzle at least partially
defines the nozzle fluid inlet.
32. A nozzle according to claim 31, wherein the side wall is tubular in shape.
33. A nozzle according to claim 31 or claim 32, wherein the nozzle fluid inlet is
formed in the side wall.
34. A nozzle according to claim 31 or claim 32, wherein the side wall extends about
an inner wall, and wherein the nozzle fluid inlet is located between the walls of the
nozzle.
35. A nozzle according to claim 34, wherein the inner wall is tubular in shape.
36. A nozzle according to claim 34 or claim 35, wherein the inner wall extends from
the first end to the second end.
37. A nozzle according to any of claims 27 to 36, wherein the second end of the
nozzle comprises the nozzle fluid outlet.
38. A nozzle according to any of claims 27 to 36, wherein the nozzle fluid outlet is
located between the first end and the second end of the nozzle.