This disclosure relates generally to blowers, and more particularly to a device
and system for reducing blower noise.
BACKGROUND
[002] Vacuum cleaner is a commonly known appliance used in homes as well as
industries for cleaning different types of surfaces by removing dust and debris by creating
vacuum Today, various types of vacuum cleaner are available such as, upright type,
robotic type, hand-held type, and drum type. However, basic parts of the vacuum cleaner
always include an intake port, a dust collecting bag, a blower, and outlet ports. Out of
these parts, the blower plays an important role in operation of the vacuum cleaner.
Conventional blowers include a fan and motor assembly to draw dirt and dust. The
conventional blowers generate air borne noise during operation, as inlet port and the
outlet ports are directly exposed to the environment. This air borne noise may originate
near the inlet port of the blower, within the blower, or at outlet ports of the blower.
Moreover, the conventional blowers cause highly turbulent flow with wake and
recirculation zones, resulting in high pressure drop and increased noise levels.
[003] Therefore, there is a need to develop a device that may attain required
pressure delivery for a given motor speed and reduce the airborne noise of the blower.
SUMMARY
[004] In one embodiment, a device for reducing blower noise is disclosed. In one
example, the device may include an intake region attached to a plurality of outlet ports of

Docket No: IIP-HCL-P0034
-3-
a blower. The device may further include an enclosure portion configured to receive an
airflow from at least one of the plurality of outlet ports through the intake region. Further,
the enclosure portion may include at least two spiral guide passages with overlapping
walls attached at a predefined angle. It should be noted that area of the at least two spiral
guided passages increases from a first end to a second end. The at least two spiral guide
passages may further include a plurality of guide vanes configured to guide the airflow
received from the at least one of the plurality outlet ports of the blower. The device may
further include a discharge region configured to discharge the airflow.
[005] In another embodiment, a system for vacuum cleaning is disclosed. In one
example, the system may include a blower. The blower may further include an inlet port
configured to intake an airflow and a plurality of outlet ports to direct the airflow to
environment. The system may further include a noise reduction device. The noise
reduction device may include an intake region attached to the plurality of outlet ports of
the blower. The noise reduction may further include an enclosure portion configured to
receive the airflow from at least one of the plurality of outlet ports through the intake
region. The enclosure portion may include at least two spiral guide passages with
overlapping walls attached at a predefined angle. It should be noted that area of the at
least two spiral guided passages increases from a first end to a second end. The at least
two spiral guide passages may include a plurality of guide vanes configured to guide the
airflow received from the at least one of the plurality outlet ports of the blower The noise
reduction device may further include a discharge region configured to discharge the
airflow.

Docket No: IIP-HCL-P0034
-4-
[006] In yet another embodiment, a method for reducing blower noise is disclosed.
The method may include receiving an airflow from at least one of a plurality of outlet ports
of a blower through an intake region of the noise reduction device The method may further
include splitting the airflow into a first airflow and a second airflow using at least two spiral
guide passages of an enclosure portion. The method may further include guiding the first
airflow and the second airflow cumulatively towards a discharge region using a plurality
of guide vanes of the at least two spiral guide passages. It should be noted that the first
airflow may be directed in a first direction using a first spiral guide passage of the at least
two spiral guide passages and the second airflow may be directed in a second direction
using a second spiral guide passage of the at least two spiral guide passages. It should
also be noted that area of the at least two spiral guide passages increases from a first
end to a second end. The method may further include discharging the first airflow and the
second through the discharge region.
[007] It is to be understood that both the foregoing general description and the
following detailed description are exemplary and explanatory only and are not restrictive
of the invention, as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[008] The accompanying drawings, which are incorporated in and constitute a part
of this disclosure, illustrate exemplary embodiments and, together with the description,
serve to explain the disclosed principles.
[009] FIG. 1 illustrates an exemplary blower within a vacuum cleaner where
various embodiments may be employed.

Docket No: IIP-HCL-P0034
-5-
[010] FIGS. 2A and 2B illustrate an isometric view and a front view of a noise
reduction device configured to reduce blower noise, in accordance with an exemplary
embodiment.
[011] FIGS. 3A and 3B illustrate a top view and a side view of a noise reduction
device configured to reduce blower noise, in accordance with an exemplary embodiment.
[012] FIGS. 4A and 4B illustrate entering and exiting airflow patterns for a noise
reduction device, in accordance with an exemplary embodiment.
[013] FIG. 5 is a flowchart of a method for reducing blower noise, in accordance
with an embodiment.
[014] FIG. 6 is a flowchart of a method for directing an airflow from a noise
reduction device to environment, in accordance with an embodiment.
DETAILED DESCRIPTION
[015] Exemplary embodiments are described with reference to the accompanying
drawings. Wherever convenient, the same reference numbers are used throughout the
drawings to refer to the same or like parts. While examples and features of disclosed
principles are described herein, modifications, adaptations, and other implementations
are possible without departing from the spirit and scope of the disclosed embodiments. It
is intended that the following detailed description be considered as exemplary only, with
the true scope and spirit being indicated by the following claims. Additional illustrative
embodiments are listed below.
[016] In FIG. 1, an exemplary blower 100 within a vacuum cleaner (not shown in
FIG. 1) is illustrated, where various embodiments may be employed. As illustrated in FIG.
1, the blower 100 may be a typical centrifugal pump and may be configured to generate

Docket No: IIP-HCL-P0034
-6-
a suction force and blowing force. The blower 100 may include an electric motor assembly
102, a stationary casing 104, a plurality of outlet ports 106, and a plurality of stationary
vanes 108. The electric motor assembly 102 may include an electric motor. The blower
100 may also include a blower fan (or impeller) (not shown in FIG. 1) connected to the
electric motor. The blower fan may include a plurality of blades that may vary based on
requirement. The plurality of blades may be selected from, but not limited to, a forward
curved, a backward curved, a radial type, an open paddle type, and a backward inclined
blade. The blower fan may be configured to generate the suction force and blowing force
and the electric motor may rotate the blower fan to generate the suction force and the
blowing force.
[017] In some embodiments, a user may operate the vacuum cleaner to collect
dust from a surface which needs to be cleaned. In response to this operation, the blower
100 of the vacuum cleaner may get triggered. As a result, the suction force may be
generated by the blower fan, when the electric motor rotates the blower fan. Further,
drawn air and dust may be separated. The separated dust may be further collected in a
dust bag inside the vacuum cleaner. On the other hand, the separated air may be drawn
by the blower 100.
[018] The air drawn may be further discharged through the plurality of outlet ports
106. In other words, the blower fan may provide kinetic energy to the air and the stationary
vanes 108 redirects the air expelled from the impeller towards the plurality of outlet ports
106. The stationary casing 104 is circular in shape as illustrated in FIG. 1 and provides
the plurality of outlet ports 106 around the periphery of the blower 100. This circular
passage design of the blower 100 may cause wakes or recirculation zones. Thus, it

Docket No: IIP-HCL-P0034
-7-
makes the flow of air highly turbulent, resulting in higher pressure drop. This in turn leads
to pressure pulses and increase in sound pressure level or noise of the air flowing out of
the blower 100 and the vacuum cleaner.
[019] To reduce blower noise, a noise reduction device 200 may be detachably
attached around the periphery of the stationary casing 104 through the plurality of outlet
ports 106. In other words, the noise reduction device 200 may encircle the blower 100.
Internal architecture and operation of the noise reduction device 200 are further explained
in detail in conjunction with FIG. 2 to FIG. 6.
[020] Referring now to FIGs. 2A and 2B, an isometric view and a front view of the
noise reduction device 200 configured to reduce blower noise are illustrated, in
accordance with an exemplary embodiment. FIG. 2A is the isometric view of the noise
reduction device 200 that depicts an intake region 202, an encloser portion including a
first spiral guide passage 204a, and a second spiral guide passage 204b, and a discharge
region including a first discharge region 206a and a second discharge region 206b. In
order to integrate the noise reduction device 200 with a blower (such as, the blower 100),
the plurality of outlet ports 106 of the blower 100 may be attached to the intake region
202 of the noise reduction device 200. In one example, the plurality of outlet ports 106
may be detachably connected to the intake region 202 through a plurality of channels, for
example, channels 202a, 202b, 202c, and 202d. The intake region 202 may also have
other channels (not visible in the isometric view, FIG. 2A) similar to the channels 202a,
202b, 202c, and 202c.
[021] Further, an enclosure portion 204 may be configured to receive an airflow
coming out of the plurality of outlet ports 106 of the blower 100 through the intake region

Docket No: IIP-HCL-P0034
-8-
202. As shown in FIG. 2A, walls of the first spiral guide passage 204a and the second
spiral guide passage 204b may overlap each other at a predefined angle. It should be
noted that in an embodiment the predefined angle may lie in a range of forty-five to sixty
degrees. Also, the predefined angle may further be selected from this range based on
application of the noise reduction device 200. In some embodiments, a first airflow and a
second airflow may be generated from the airflow received by the enclosure portion 204.
The first spiral guide passage 204a and the second spiral guide passage 204b may split
the airflow into two airflows in order to generate the first airflow and the second airflow.
The first airflow may be directed in a first direction using the first spiral guide passage
204a and the second airflow may be directed in a second direction using the second spiral
guide passage 204b. It should also be noted that area of the first spiral passage 204a and
204b may increases from one end to another.
[022] The first spiral guide passage 204a and the second spiral guide passage
204b may include a plurality of guide vanes, such as, guide vanes 208a and 208b. The
plurality of guide vanes associated with the first spiral guide passage 204a and 204b may
guide the first airflow and the second airflow cumulatively towards the discharge region.
The first discharge region 206a may be associated with the first spiral guide passage
204a. Thus, the first airflow may be discharged to the environment though the first
discharge region 206a. Similarly, the second discharge region 206b may be associated
with the second spiral guide passage 204b to discharge the second airflow to the
environment. FIG. 2B is the front view of the noise reduction device 200 that illustrates
the enclosure portion 204, and the first spiral guide passage 204a and the second spiral
guide passage 204b inside the enclosure portion 204.

Docket No: IIP-HCL-P0034
-9-
[023] Referring now to FIGs. 3A and 3B, a top view and a side view of a noise
reduction device 300 configured to reduce blower noise are illustrated, in accordance with
an exemplary embodiment. FIG. 3A is the top view of the noise reduction device 300. The
top view of the noise reduction device 300 depicts a discharge region. By way of an
example, in the FIG. 3A, illustrated discharge region is a first discharge region 302 (similar
to the first discharge region 206a) associated with a first spiral guide passage. In another
top view (not shown), other discharge region may be visible. For example, a second
discharge region (similar to the second discharge region 206b) associated with a second
spiral guide passage. The first discharge region 302 includes a plurality of exit ports
302(1) to 302(n1). Here, ‘n1’ represents total number of exit ports in the first discharge
region 302. The number of exit ports in the first discharge region 302 may vary according
to need.
[024] FIG. 3B is the side view of the noise reduction device 300. The side view
depicts the first discharge region 302 that includes some of the plurality of exit ports 302(1)
to 302(q1), such that, ‘q1’ is less than ‘n1’. Further, the side view also depicts two exit ports
304 (n2-1) and 304 (n) (i.e., last two exit ports) of the second discharge region 304. Here,
‘n2’ represents total number of exit ports in the second discharge region 304. In some
embodiments, ‘n1’ is equal to ‘n2’ and in some other embodiments, ‘n1’ is not equal to ‘n2’.
[025] Referring now to FIGs. 4A and 4B, entering and exiting airflow patterns in a
noise reduction device 400 are illustrated, in accordance with an exemplary embodiment.
FIG. 4A illustrates the noise reduction device 400. The noise reduction device 400 is
analogous to the noise reduction device 200 and 300. The noise reduction device 400
may be connected to a blower (not shown in FIG. 4A) through a plurality of outlet ports

Docket No: IIP-HCL-P0034
-10-
402 (analogous to the plurality of outlet ports 106). Further, the noise reduction device
400 includes a first spiral guide passage 404a (same as the spiral guide passage 204a),
a second spiral guide passage 404b (same as the spiral guide passage 204b), that may
split the incoming airflow from the plurality of outlet ports 402a. Further the first spiral
guide passage 404a and the second spiral guide passage 404b may direct the airflow
towards respective airflow exit regions (same as the discharge region 206a and 206b).
This is already described in greater detail in conjunction with FIGs. 2-3. Further, a first
airflow 406a and second airflow 406b exiting out of the noise reduction device 400 are
depicted.
[026] FIG. 4B depicts generated airflow patterns 408, 410, and 412, during
operation of the noise reduction device 400. The airflow pattern 408 may be generated
when air enters the noise reduction device 400 from the outlet ports 402 of the blower.
Further, airflow patterns 410a and 410b may be generated, when the first airflow 406a
and the second airflow 406b are directed towards the exit regions. Consequently, the
airflow patterns 412a and 412b may be generated, when the first airflow 406a and the
second airflow 406b exit from the exit region to the environment.
[027] In short, the disclosed noise reduction device may collect an airflow coming
out of a plurality of outlet ports of a blower and then may guide the airflow to exit
cumulatively through a gradually increasing area of an enclosure portion. Further, the
airflow may be divided into two halves (i.e., a first airflow and a second airflow) by using
the at least two spiral guide passages of the enclosure portion. Additionally, the first
airflow and the second airflow may be directed in two opposite directions over a larger

Docket No: IIP-HCL-P0034
-11-
external area. As a result, flow velocity and noise or Sound Pressure Level (SPL) may
get reduced before the airflow reaches to the environment.
[028] Referring now to FIG. 5, a method 500 for reducing blower noise is depicted
via a flowchart, in accordance with an embodiment. Each step of the method 500 may be
executed by a noise reduction device (analogous to the noise reduction devices 200, 300,
and 400). At step 502, an airflow may be received by the noise reduction device. In
particular, the airflow may be received through an intake region (same as the intake region
202) of the noise reduction device. The airflow may be received from a plurality of outlet
ports of a blower (similar to the plurality of outlet ports 104 of the blower100) associated
with a vacuum cleaner. After receiving the airflow, at step 504, the airflow may be split
into a first airflow and a second airflow. To split the airflow, at least two spiral guide
passages of an enclosure portion (similar to the at least two spiral guide passages 204a
and 204b of the enclosure portion 204) may be employed in the noise reduction device.
[029] At step 506, the first airflow and the second airflow may be guided
cumulatively towards a discharge region (same as the first discharge region 206a and
302, and the second discharge region 206b and 304). It should be noted that a plurality
of guide vanes (for example, the guide vanes 208a and 208b) may be used to guide the
first airflow and the second airflow. At step 506a, the first airflow may be directed in a first
direction using a first spiral guide passage of the at least two spiral guide passages and
the second airflow be directed in a second direction using a second spiral guide passage
of the at least two spiral guide passages. In some embodiments, the first airflow direction
may be opposite to the second airflow direction. It should also be noted that area of the
at least two spiral guide passages increases from a first end to a second end.

Docket No: IIP-HCL-P0034
-12-
[030] At step 508, the first airflow and the second may be discharged out the noise
reduction device through the discharge region of the noise reduction device. The
discharge region may include a plurality of exit ports (for example, the exit ports 302(1) to
302(n1)).
[031] Referring now to FIG. 6, a method 600 for directing the airflow from the noise
reduction device to environment is depicted via a flowchart, in accordance with an
embodiment. At step 602, the plurality of outlet ports may be linked to environment via
the enclosure portion and direct exposure of each of the plurality of outlet ports may be
blocked to environment. It should be noted that the enclosure portion may encircle the
plurality of outlet ports of the blower through the intake region.
[032] At step 604, the airflow may be split into the first airflow and the second
airflow using the at least two spiral guide passages of the enclosure portion. It should be
noted that the at least two spiral guide passages may have overlapping walls attached at
a predefined angle, and the predefined angle lies in a range of forty-five to sixty degrees.
Further, it should also be noted that radius of the enclosure portion gradually increases
from the intake region to the discharge region. At step 606, the airflow including the first
airflow and the second airflow may be directed out of the noise reduction device to
environment.
[033] As will further be appreciated by those skilled in the art, current systems and
devices lack the mechanism to effectively reduce blower noise. The disclosed noise
reduction device may provide a barrier to propagate sound or noise generated by the
airflow of high velocity. The walls of the at least two spiral passages cover the plurality of
outlet ports of the blower, when the noise reduction device is integrated with the blower.

Docket No: IIP-HCL-P0034
-13-
Thus, none of the plurality of outlet ports of the blower is directly open to the atmosphere
that may help in providing the barrier to sound propagation. The obstructed sound or
sound waves get reflected within the enclosure portion and dissipate their energy before
it reaches to the atmosphere. Moreover, the disclosed noise reduction device achieves a
large pressure delivery for a given motor speed. In one example, integration of blower
and the noise reduction device enables supply of a given pressure at a relatively low
motor speed and with a fast response time.
[034] Further, simulations are performed for the integrated noise reduction device
and blower assembly, and test results showed reduction in noise level in comparison to
the conventional systems or vacuum cleaners.
[035] The specification has described a device, system, and method for reducing
blower noise. The illustrated steps are set out to explain the exemplary embodiments
shown, and it should be anticipated that ongoing technological development will change
the manner in which particular functions are performed. These examples are presented
herein for purposes of illustration, and not limitation. Further, the boundaries of the
functional building blocks have been arbitrarily defined herein for the convenience of the
description. Alternative boundaries can be defined so long as the specified functions and
relationships thereof are appropriately performed. Alternatives (including equivalents,
extensions, variations, deviations, etc., of those described herein) will be apparent to
persons skilled in the relevant art(s) based on the teachings contained herein. Such
alternatives fall within the scope and spirit of the disclosed embodiments.
[036] It is intended that the disclosure and examples be considered as exemplary
only, with a true scope of disclosed embodiments being indicated by the following claims.

CLAIMS
WHAT IS CLAIMED IS:
1. A device (200) for reducing blower noise, the device (200) comprising:
an intake region (202) attached to a plurality of outlet ports (106) of a blower
(100);
an enclosure portion (204) configured to receive an airflow from at least one of
the plurality of outlet ports (106) through the intake region (202), wherein the enclosure
portion (204) comprises:
at least two spiral guide passages (204a), (204b) with overlapping walls
attached at a predefined angle, wherein area of the at least two spiral guided
passages (204a), (204b) increases from a first end to a second end, and wherein
the at least two spiral guide passages (204a), (204b) further comprise:
a plurality of guide vanes (208a), (208b) configured to guide the
airflow received from the at least one of the plurality outlet ports (106) of
the blower (100); and
a discharge region configured to discharge the airflow.
2. The device (200) of claim 1, wherein the enclosure portion (204) encircles the plurality
of outlet ports (106) of the blower (100) through the intake region (202), and wherein the
enclosure portion (204) connects the plurality of outlet ports (106) to the environment and
blocks direct exposure of each of the plurality of outlet ports (106) to the environment.
3. The device (200) of claim 1, wherein the at least two spiral guide passages (204a),
(204b) are configured to split the airflow into a first airflow and a second airflow, wherein
a first spiral guide passage (204a) of the at least two spiral guide passages (204a), (204b)
directs the first airflow in a first direction and a second spiral guide passage (204b) of the
at least two spiral guide passages (204a), (204b) directs the second airflow in a second
direction, and wherein the first airflow and the second airflow are directed towards the
discharge region.

Docket No: IIP-HCL-P0034
-15-
4. The device (200) of claim 1, wherein the predefined angle lies in a range of forty-five
to sixty degrees.
5. The device (200) of claim 1, wherein radius of the enclosure portion (204) gradually
increases from the intake region (202) to the discharge region.
6. The device (200) of claim 1, wherein the blower (100) is part of a vacuum cleaner.
7. A system for vacuum cleaning, the system comprising:
a blower (100) comprising:
an inlet port configured to intake an airflow; and
a plurality of outlet ports (106) to direct the airflow to environment; and
a noise reduction device (200) comprising:
an intake region (202) attached to the plurality of outlet ports (106) of the
blower (100);
an enclosure portion (204) configured to receive the airflow from at least
one of the plurality of outlet ports (106) through the intake region (202), wherein
the enclosure portion (204) comprises:
at least two spiral guide passages (204a), (204b) with
overlapping walls attached at a predefined angle, wherein area of the at
least two spiral guided passages (204a), (204b) increases from a first end
to a second end, and wherein the at least two spiral guide passages
(204a), (204b) further comprise a plurality of guide vanes (208a), (208b)
configured to guide the airflow received from the at least one of the
plurality outlet ports (106) of the blower (100); and
a discharge region configured to discharge the airflow.
8. The system of claim 7, wherein the blower (100) comprises an impeller to withdraw the
airflow.
9. A method (500) for reducing blower noise, the method comprising:

Docket No: IIP-HCL-P0034
-16-
receiving (502), by a noise reduction device (200), an airflow from at least one of
a plurality of outlet ports (106) of a blower (100) through an intake region (202) of the
noise reduction device (200);
splitting (504), by the noise reduction device (200), the airflow into a first airflow
and a second airflow using at least two spiral guide passages (204a), (204b) of an
enclosure portion (204);
guiding (506), by the noise reduction device (200), the first airflow and the second
airflow cumulatively towards a discharge region using a plurality of guide vanes (208a),
(208b) of the at least two spiral guide passages (204a), (204b), wherein the first airflow
is directed in a first direction using a first spiral guide passage (204a) of the at least two
spiral guide passages (204a), (204b) and the second airflow is directed in a second
direction using a second spiral guide passage (204b) of the at least two spiral guide
passages (204a), (204b), and wherein area of the at least two spiral guide passages
(204a), (204b) increases from a first end to a second end; and
discharging (508), by the noise reduction device (200), the first airflow and the
second through the discharge region.
10. The method (500) of claim 9, further comprising:
linking (602) the plurality of outlet ports (106) to environment via the enclosure
portion (204) and blocking direct exposure of each of the plurality of outlet ports (106) to
environment, wherein radius of the enclosure portion (204) gradually increases from the
intake region (202) to the discharge region.; and
directing (606) the airflow comprising the first airflow and the second airflow to
environment via the enclosure portion (204), wherein the at least two spiral guide
passages (204a), (204b) of the enclosure portion (204) have overlapping walls attached
at a predefined angle, and wherein the predefined angle lies in a range of forty-five to
sixty degrees.