U.S. patent application number 15/786628 was filed with the patent office on 2018-04-26 for motor module and vacuum cleaner.
The applicant listed for this patent is Nidec Corporation. Invention is credited to Jun MURAKAMI, Yuuichi SAKUMA.
Application Number | 20180110384 15/786628 |
Document ID | / |
Family ID | 61971667 |
Filed Date | 2018-04-26 |
United States Patent
Application |
20180110384 |
Kind Code |
A1 |
SAKUMA; Yuuichi ; et
al. |
April 26, 2018 |
MOTOR MODULE AND VACUUM CLEANER
Abstract
This motor module includes a motor, a fan, and a casing arranged
to house the motor and the fan therein. The casing includes a
tubular body portion arranged to extend in an axial direction, an
air inlet, an air outlet, a flow passage, and a partitioning
portion. The flow passage is a space arranged to join the air inlet
and the air outlet to each other between the body portion and the
motor. The partitioning portion is arranged in the flow passage to
partition the flow passage. The flow passage includes a fan
accommodating portion, a first silencing chamber arranged to be in
communication with the fan accommodating portion through a first
communicating passage, and a second silencing chamber arranged to
be in communication with the first silencing chamber through a
second communicating passage. The second silencing chamber is
arranged to be in communication with the air outlet. The first
silencing chamber is arranged to have a flow passage
cross-sectional area greater than that of the first communicating
passage. The second silencing chamber is arranged to have a flow
passage cross-sectional area greater than that of the second
communicating passage. Two expansion-type silencers, one defined by
the first communicating passage and the first silencing chamber and
the other defined by the second communicating passage and the
second silencing chamber, are arranged between the fan and the air
outlet, so that noise generated in the fan can be reduced with high
efficiency.
Inventors: |
SAKUMA; Yuuichi; (Kyoto,
JP) ; MURAKAMI; Jun; (Kyoto, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Nidec Corporation |
Kyoto |
|
JP |
|
|
Family ID: |
61971667 |
Appl. No.: |
15/786628 |
Filed: |
October 18, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A47L 5/24 20130101; A47L
9/2884 20130101; A47L 9/22 20130101; A47L 9/0081 20130101 |
International
Class: |
A47L 5/24 20060101
A47L005/24; A47L 9/00 20060101 A47L009/00; A47L 9/22 20060101
A47L009/22 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 21, 2016 |
JP |
2016-206579 |
Claims
1. A motor module comprising: a motor including a rotating portion
arranged to rotate about a rotation axis; a fan arranged on a first
axial side of the motor to rotate together with the rotating
portion; and a casing arranged to house the motor and the fan
therein; wherein the casing includes: a tubular body portion
arranged to extend in an axial direction; an air inlet arranged on
the first axial side of the fan; an air outlet arranged on a second
axial side of the fan and radially outside of the motor; a flow
passage being a space arranged to join the air inlet and the air
outlet to each other between the body portion and the motor; and at
least one partitioning portion arranged in the flow passage to
partition the flow passage; the flow passage includes: a fan
accommodating portion arranged to have the fan accommodated
therein, and arranged to be in direct communication with the air
inlet; a first silencing chamber arranged to be in communication
with the fan accommodating portion through a first communicating
passage; and a second silencing chamber arranged to be in
communication with the first silencing chamber through a second
communicating passage, and arranged to be in direct or indirect
communication with the air outlet; the first silencing chamber is
arranged to have a flow passage cross-sectional area greater than a
flow passage cross-sectional area of the first communicating
passage; and the second silencing chamber is arranged to have a
flow passage cross-sectional area greater than a flow passage
cross-sectional area of the second communicating passage.
2. The motor module according to claim 1, wherein the at least one
partitioning portion includes: a plate-shaped first partitioning
portion arranged between the fan accommodating portion and the
first silencing chamber; and a plate-shaped second partitioning
portion arranged between the first and second silencing
chambers.
3. The motor module according to claim 2, wherein the first
partitioning portion includes: a first plate portion arranged to
extend substantially perpendicularly to the axial direction; and a
first bend portion arranged to extend from the first plate portion
to the second axial side.
4. The motor module according to claim 2, wherein the second
partitioning portion includes: a second plate portion arranged to
extend substantially perpendicularly to the axial direction; and a
second bend portion arranged to extend from the second plate
portion to the second axial side.
5. The motor module according to claim 1, wherein each of the first
and second communicating passages is arranged along an inner wall
of the body portion; and the first and second communicating
passages are arranged to overlap at least in part with each other
when viewed in the axial direction.
6. The motor module according to claim 1, wherein the first
communicating passage is arranged along an inner wall of the body
portion; the second communicating passage is arranged along the
motor; and the first and second communicating passages are arranged
at different positions when viewed in the axial direction.
7. The motor module according to claim 1, wherein the casing
further includes a motor covering portion arranged between the
motor and the flow passage; and at least a portion of the flow
passage is surrounded by the motor covering portion and the body
portion.
8. The motor module according to claim 1, wherein the air outlet is
a through hole defined in the body portion, and is arranged to be
in direct communication with the second silencing chamber.
9. The motor module according to claim 8, wherein the casing
further includes a partition wall portion arranged to divide the
second silencing chamber and a space on the second axial side of
the second silencing chamber from each other on the second axial
side of the air outlet.
10. The motor module according to claim 1, wherein the casing
includes: a first casing defined by a single monolithic member; and
a second casing defined by a single monolithic member; and the
first and second casings include contact surfaces arranged to be in
contact with each other on a plane passing through the rotation
axis.
11. The motor module according to claim 10, wherein the first
casing includes a projecting portion arranged to project from the
plane toward the second casing; the second casing includes a
recessed portion recessed from the plane; and the projecting
portion is fitted into the recessed portion.
12. A handy-type, upright-type, or stick-type vacuum cleaner
comprising: a suction head; a dust separation portion arranged to
separate dust included in an air flow from the air flow; and the
motor module of claim 10; wherein the casing includes a handle
portion arranged to be substantially symmetrical with respect to
the plane; and the motor module is arranged to cause gas to be
sucked into the air inlet through the suction head and the dust
separation portion and be discharged through the air outlet.
13. A canister-type vacuum cleaner comprising: a suction head; a
dust separation portion arranged to separate dust included in an
air flow from the air flow; a hose portion arranged to join the
suction head and the dust separation portion to each other; and the
motor module of claim 1; wherein the motor module is arranged to
cause gas to be sucked into the air inlet through the suction head,
the hose portion, and the dust separation portion and be discharged
through the air outlet.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to Japanese
Patent Application No. 2016-206579 filed on Oct. 21, 2016. The
entire contents of this application are hereby incorporated herein
by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
[0002] The present invention relates to a motor module and a vacuum
cleaner including the motor module.
2. Description of the Related Art
[0003] Apparatuses, such as vacuum cleaners, which are required to
create suction typically have a motor and a fan installed therein.
In recent years, in addition to conventional canister-type vacuum
cleaners, small-sized vacuum cleaners called handy-type,
upright-type, or stick-type vacuum cleaners have become widespread.
A known handy-type vacuum cleaner including a motor and a fan is
described in, for example, JP-A 2016-67664.
[0004] In recent years, there has been a demand for a reduction in
noise of vacuum cleaners because of, for example, an increased
number of apartment houses. In addition, the small-sized vacuum
cleaners can be used in various places and situations. Accordingly,
a reduction in noise is more strongly demanded of the small-sized
vacuum cleaners than of larger vacuum cleaners. That is, there is a
demand for a reduction in noise of a motor module including a motor
and a fan.
SUMMARY OF THE INVENTION
[0005] A motor module according to a preferred embodiment of the
present invention includes a motor including a rotating portion
arranged to rotate about a rotation axis; a fan arranged on a first
axial side of the motor to rotate together with the rotating
portion; and a casing arranged to house the motor and the fan
therein. The casing includes a tubular body portion arranged to
extend in an axial direction; an air inlet arranged on the first
axial side of the fan; an air outlet arranged on a second axial
side of the fan and radially outside of the motor; a flow passage
being a space arranged to join the air inlet and the air outlet to
each other between the body portion and the motor; and at least one
partitioning portion arranged in the flow passage to partition the
flow passage. The flow passage includes a fan accommodating portion
arranged to have the fan accommodated therein, and arranged to be
in direct communication with the air inlet; a first silencing
chamber arranged to be in communication with the fan accommodating
portion through a first communicating passage; and a second
silencing chamber arranged to be in communication with the first
silencing chamber through a second communicating passage, and
arranged to be in direct or indirect communication with the air
outlet. The first silencing chamber is arranged to have a flow
passage cross-sectional area greater than a flow passage
cross-sectional area of the first communicating passage. The second
silencing chamber is arranged to have a flow passage
cross-sectional area greater than a flow passage cross-sectional
area of the second communicating passage.
[0006] According to the above preferred embodiment of the present
invention, the first communicating passage and the first silencing
chamber together define an expansion-type silencer. In addition,
the second communicating passage and the second silencing chamber
together define another expansion-type silencer. With the two
expansion-type silencers being arranged between the fan and the air
outlet, noise generated in the fan can be reduced with high
efficiency.
[0007] The above and other elements, features, steps,
characteristics and advantages of the present invention will become
more apparent from the following detailed description of the
preferred embodiments with reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a side view of a vacuum cleaner according to a
first preferred embodiment of the present invention.
[0009] FIG. 2 is a sectional view of a motor module according to
the first preferred embodiment.
[0010] FIG. 3 is a sectional view of the motor module according to
the first preferred embodiment taken along line A-A in FIG. 2.
[0011] FIG. 4 is a perspective view of a first casing of the motor
module according to the first preferred embodiment.
[0012] FIG. 5 is a sectional view of a motor module according to a
modification of the first preferred embodiment.
[0013] FIG. 6 is a sectional view of a motor module according to
another modification of the first preferred embodiment.
[0014] FIG. 7 is a sectional view of a motor module according to
yet another modification of the first preferred embodiment.
[0015] FIG. 8 is a sectional view of a motor module according to
yet another modification of the first preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] Hereinafter, vacuum cleaners including a motor module
according to preferred embodiments of the present invention will be
described. It is assumed herein that a direction parallel to a
rotation axis of a motor is referred to by the term "axial
direction", "axial", or "axially", that directions perpendicular to
the rotation axis of the motor are each referred to by the term
"radial direction", "radial", or "radially", and that a direction
along a circle centered on the rotation axis of the motor is
referred to by the term "circumferential direction",
"circumferential", or "circumferentially". It is also assumed
herein that a vertical direction in FIG. 2 is a vertical direction,
and that a side on which a handle portion is arranged with respect
to a rechargeable battery is an upper side. The shape of each
member or portion and relative positions of different members or
portions will be described based on the above assumptions. It
should be noted, however, that the above definition of the vertical
direction and the upper and lower sides is not meant to restrict in
any way the orientation of a motor module according to any
preferred embodiment of the present invention at the time of
manufacture or when in use.
1-1. Structure of Vacuum Cleaner
[0017] FIG. 1 is a side view of a vacuum cleaner 1 according to a
first preferred embodiment of the present invention. The vacuum
cleaner 1 includes a motor module 10, a dust separation portion 11,
and a nozzle 12. The vacuum cleaner 1 is a so-called handy-type
vacuum cleaner.
[0018] FIG. 2 is a sectional view of the motor module 10. Referring
to FIG. 2, the motor module 10 includes a casing 20, a motor 31, a
fan 32, and a rechargeable battery 33.
[0019] The casing 20 is arranged to house the motor 31, the fan 32,
and the rechargeable battery 33 therein. The casing 20 includes an
air inlet 211, which is arranged on one axial side (this side will
be hereinafter referred to as a first axial side) of the fan 32 and
is arranged to bring an interior of the dust separation portion 11
into communication with a space inside of the casing 20 in which
the fan 32 is housed, and air outlets 212 defined in a side surface
of the casing 20. In addition, the casing 20 has a flow passage 40,
which is a space arranged to join the air inlet 211 to the air
outlets 212, defined inside thereof. The structure of the casing 20
will be described in detail below.
[0020] The motor 31 is a brushless motor. The motor 31 includes a
rotating portion arranged to rotate about a rotation axis 9. The
fan 32 is arranged on the first axial side of the motor 31. In
addition, the fan 32 is arranged to rotate together with the
rotating portion of the motor 31. The fan 32 is a so-called
centrifugal fan, and is arranged to generate air flows traveling
radially outward through the rotation thereof. Thus, the fan 32 is
arranged to generate air flows traveling from the air inlet 211
toward the air outlets 212 in the flow passage 40 of the casing 20.
The rechargeable battery 33 is arranged to supply driving power to
the motor 31.
[0021] The dust separation portion 11 is arranged on the first
axial side of the motor module 10. The nozzle 12 is arranged on the
first axial side of the dust separation portion 11. The dust
separation portion 11 is arranged to separate dust and trash
included in an air flow sucked through the nozzle 12 from the air
flow. The dust separation portion 11 may be arranged to separate
the dust and the trash using a paper bag, or may alternatively be
arranged to separate the dust and the trash using a cyclone
separator.
[0022] Once the vacuum cleaner 1 is driven, the motor 31 is driven
to generate air flows which travel from the nozzle 12 toward the
air outlets 212 through the interior of the dust separation portion
11, the air inlet 211, and an interior of the motor module 10.
Thus, dust and trash are sucked through the nozzle 12 together with
the air flows. In the dust separation portion 11, the dust and the
trash are removed from the air flows sucked through the nozzle 12.
Then, the air flows, from which the dust and the trash have been
removed, pass through the interior of the motor module 10, and are
discharged through the air outlets 212.
1-2. Structure of Casing
[0023] Next, the specific structure of the casing 20 will now be
described below with reference to FIGS. 2, 3, and 4. FIG. 3 is a
sectional view of the motor module 10 taken along line A-A in FIG.
2. FIG. 4 is a perspective view of a first casing 71, which will be
described below.
[0024] The casing 20 has a body portion 21, a handle portion 22,
and a rechargeable battery accommodating portion 23.
[0025] The body portion 21 is a tubular portion arranged to extend
in an axial direction. The air inlet 211, which is arranged to pass
through in the axial direction, is defined in the body portion 21
on the first axial side. The air inlet 211 is arranged on the first
axial side of the fan 32.
[0026] In addition, the air outlets 212, each of which is a through
hole, are defined in a side surface of the body portion 21. Each
air outlet 212 is arranged on a second axial side (i.e., a side
opposite to the first axial side) of the fan 32 and radially
outside of the motor 31.
[0027] Each of the handle portion 22 and the rechargeable battery
accommodating portion 23 is arranged on the second axial side of
the air outlets 212. The handle portion 22 is arranged on the upper
side of the rechargeable battery accommodating portion 23. Here,
the handle portion 22 is formed by a handle hole 221 arranged to
pass through in a left-right direction, which is perpendicular to
both the axial direction and the vertical direction, and a
graspable portion 222 arranged to extend in the axial direction on
the upper side of the handle hole 221. The rechargeable battery 33
is accommodated in the rechargeable battery accommodating portion
23.
[0028] Referring to FIGS. 2 and 4, the casing 20 includes an
upper-side wall portion 51, a lower-side wall portion 52, and a
middle wall portion 53, which are arranged to partition the space
inside of the casing 20.
[0029] The upper-side wall portion 51, the lower-side wall portion
52, and the middle wall portion 53 are arranged to partition the
space inside of the casing 20 into the flow passage 40 and a
portion outside of the flow passage 40. In the present preferred
embodiment, the flow passage 40 includes a fan accommodating
portion 41 arranged to have the fan 32 accommodated therein, and an
upper-side flow passage 42 and a lower-side flow passage 43 each of
which is arranged to extend from the fan accommodating portion 41
to the second axial side. That is, the flow passage 40 according to
the present preferred embodiment is arranged to branch out into the
upper-side flow passage 42 and the lower-side flow passage 43 on a
downstream side of the fan 32.
[0030] The upper-side flow passage 42 is arranged above the motor
31. The lower-side flow passage 43 is arranged below the motor 31.
The upper-side wall portion 51 is arranged to divide the upper-side
flow passage 42 and the portion outside of the flow passage 40 from
each other above the motor 31. The lower-side wall portion 52 is
arranged to divide the lower-side flow passage 43 and the portion
outside of the flow passage 40 below the motor 31. In addition, the
middle wall portion 53 is arranged to extend in the vertical
direction to join an end portion of the upper-side wall portion 51
on the first axial side and an end portion of the lower-side wall
portion 52 on the first axial side to each other. As a result, the
fan accommodating portion 41 and a space in which the motor 31 is
accommodated are divided from each other.
[0031] The upper-side wall portion 51 includes an upper-side motor
covering portion 511 and an upper-side partition wall portion 512.
The lower-side wall portion 52 includes a lower-side motor covering
portion 521 and a lower-side partition wall portion 522. Each of
the upper-side motor covering portion 511 and the lower-side motor
covering portion 521 is arranged to extend in the axial direction
and the left-right direction to assume the shape of a plate. The
upper-side motor covering portion 511 is arranged between the motor
31 and the upper-side flow passage 42. The lower-side motor
covering portion 521 is arranged between the motor 31 and the
lower-side flow passage 43.
[0032] Accordingly, the upper-side flow passage 42 is surrounded by
the upper-side motor covering portion 511 and the body portion 21
at a position radially overlapping with the upper-side motor
covering portion 511. In addition, the lower-side flow passage 43
is surrounded by the lower-side motor covering portion 521 and the
body portion 21 at a position radially overlapping with the
lower-side motor covering portion 521.
[0033] Because the upper-side motor covering portion 511 is
arranged between the motor 31 and the upper-side flow passage 42,
and the lower-side motor covering portion 521 is arranged between
the motor 31 and the lower-side flow passage 43 as described above,
the shape of each of the upper-side and lower-side flow passages 42
and 43 can be defined regardless of the shape of the motor 31.
Thus, flow passage resistance in each of the upper-side and
lower-side flow passages 42 and 43 and silencing effects, which
will be described below, can remain the same even if the motor 31
is replaced with a motor having a different shape.
[0034] Each of the upper-side partition wall portion 512 and the
lower-side partition wall portion 522 is arranged to extend in the
vertical direction and the left-right direction to assume the shape
of a plate. The upper-side partition wall portion 512 is arranged
to extend from an end portion of the upper-side motor covering
portion 511 on the second axial side to an inner wall of the body
portion 21. The upper-side partition wall portion 512 is thus
arranged to divide the upper-side flow passage 42 and a space which
is not a flow passage and which is on the second axial side of the
upper-side flow passage 42 from each other on the second axial side
of the upper-side flow passage 42. In other words, the upper-side
partition wall portion 512 is arranged to divide a second silencing
chamber 424, which will be described below, and the space which is
not a flow passage and which is on the second axial side of the
second silencing chamber 424 from each other on the second axial
side of the air outlets 212.
[0035] The lower-side partition wall portion 522 is arranged to
extend from an end portion of the lower-side motor covering portion
521 on the second axial side to the inner wall of the body portion
21. The lower-side partition wall portion 522 is thus arranged to
divide the lower-side flow passage 43 and a space which is not a
flow passage and which is on the second axial side of the
lower-side flow passage 43 from each other on the second axial side
of the lower-side flow passage 43. In other words, the lower-side
partition wall portion 522 is arranged to divide a second silencing
chamber 434, which will be described below, and the space which is
not a flow passage and which is on the second axial side of the
second silencing chamber 434 from each other on the second axial
side of the air outlets 212.
[0036] As described above, the upper-side wall portion 51 is
arranged to partition a space inside of the casing 20 into the
upper-side flow passage 42 and a space outside of the flow passage
40, while the lower-side wall portion 52 is arranged to partition a
space inside of the casing 20 into the lower-side flow passage 43
and a space outside of the flow passage 40. Thus, the shape of each
of the upper-side and lower-side flow passages 42 and 43 can be
defined without being affected by a space outside of the flow
passage 40. Accordingly, an air flow is prevented from striking
against a portion such as, for example, the handle portion 22, the
rechargeable battery accommodating portion 23, or the rechargeable
battery 33 to cause noise. In addition, the flow passage resistance
in each of the upper-side and lower-side flow passages 42 and 43
and the silencing effects, which will be described below, can
remain the same regardless of the shapes of the handle portion 22,
the rechargeable battery accommodating portion 23, and the
rechargeable battery 33.
[0037] The casing 20 includes plate-shaped partitioning portions
61, 62, 63, and 64 each of which is arranged in the flow passage 40
to partition the flow passage 40. Specifically, the four
partitioning portions 61 to 64 include an upper-side first
partitioning portion 61 arranged to divide the fan accommodating
portion 41 and the upper-side flow passage 42 from each other, an
upper-side second partitioning portion 62 arranged to partition the
upper-side flow passage 42, a lower-side first partitioning portion
63 arranged to divide the fan accommodating portion 41 and the
lower-side flow passage 43 from each other, and a lower-side second
partitioning portion 64 arranged to partition the lower-side flow
passage 43.
[0038] The upper-side first partitioning portion 61 includes a
first plate portion 611 and a first bend portion 612. The first
plate portion 611 is arranged to extend substantially
perpendicularly to the axial direction on the first axial side of
the motor 31 and on the second axial side of the fan 32. The first
bend portion 612 is arranged to extend from the first plate portion
611 to the second axial side. The upper-side second partitioning
portion 62 includes a second plate portion 621 and a second bend
portion 622. The second plate portion 621 is arranged to extend
substantially perpendicularly to the axial direction on the second
axial side of the upper-side first partitioning portion 61 and on
the first axial side of the upper-side partition wall portion 512.
The second bend portion 622 is arranged to extend from the second
plate portion 621 to the second axial side
[0039] Thus, the upper-side flow passage 42 includes a first
communicating passage 421, a first silencing chamber 422, a second
communicating passage 423, and the second silencing chamber
424.
[0040] The first communicating passage 421 is a space arranged to
extend in the axial direction between the upper-side first
partitioning portion 61 and an inner wall of an upper portion of
the body portion 21. Specifically, the first communicating passage
421 is arranged to bring the fan accommodating portion 41 and the
first silencing chamber 422 into communication with each other
between the first bend portion 612 and the inner wall of the upper
portion of the body portion 21. The first silencing chamber 422 is
a space defined on the second axial side of the upper-side first
partitioning portion 61 and the first communicating passage 421, on
the upper side of the upper-side motor covering portion 511, on a
radially inner side of the inner wall of the body portion 21, and
on the first axial side of the upper-side second partitioning
portion 62 and the second communicating passage 423.
[0041] The second communicating passage 423 is a space arranged to
extend in the axial direction between the upper-side second
partitioning portion 62 and the upper-side motor covering portion
511. Specifically, the second communicating passage 423 is arranged
to bring the first and second silencing chambers 422 and 424 into
communication with each other between the second bend portion 622
and the upper-side motor covering portion 511. The second silencing
chamber 424 is a space defined on the second axial side of the
upper-side second partitioning portion 62 and the second
communicating passage 423, on the upper side of the upper-side
motor covering portion 511, on the radially inner side of the inner
wall of the body portion 21, and on the first axial side of the
upper-side partition wall portion 512. A portion of the body
portion 21 which contributes to defining the second silencing
chamber 424 includes three of the air outlets 212, each of which is
a through hole, on a left-hand side and other three of the air
outlets 212 on a right-hand side. That is, each of these air
outlets 212 is in direct communication with the second silencing
chamber 424. Note that each of these air outlets 212 may
alternatively be in indirect communication with the second
silencing chamber 424.
[0042] The lower-side flow passage 43 is similar in structure to
the upper-side flow passage 42 turned upside down. Accordingly, the
lower-side first partitioning portion 63 and the lower-side second
partitioning portion 64 are similar in shape to the upper-side
first partitioning portion 61 and the upper-side second
partitioning portion 62, respectively, turned upside down.
Accordingly, similarly to the upper-side flow passage 42, the
lower-side flow passage 43 includes a first communicating passage
431, a first silencing chamber 432, a second communicating passage
433, and the second silencing chamber 434. The first communicating
passage 431, the first silencing chamber 432, the second
communicating passage 433, and the second silencing chamber 434 of
the lower-side flow passage 43 are similar in structure to the
first communicating passage 421, the first silencing chamber 422,
the second communicating passage 423, and the second silencing
chamber 424, respectively, of the upper-side flow passage 42.
[0043] The upper-side flow passage 42 and the lower-side flow
passage 43 are arranged to have different dimensions as measured in
the vertical direction. The dimension of each portion of the
upper-side flow passage 42 as measured in the vertical direction is
greater than the dimension of a corresponding portion of the
lower-side flow passage 43 as measured in the vertical direction.
Thus, the dimension of the upper-side second partitioning portion
as measured in the vertical direction is greater than the dimension
of the lower-side second partitioning portion 64 as measured in the
vertical direction. In the case where the flow passage 40 is
arranged to branch out into the upper-side flow passage 42 and the
lower-side flow passage 43 on the downstream side of the fan 32,
the upper-side flow passage 42 and the lower-side flow passage 43
may be arranged to have different flow passage cross-sectional
areas as described above. Descriptions of features of the
lower-side flow passage 43 which are shared by the upper-side flow
passage 42 are omitted.
[0044] Once the motor 31 is driven to cause the fan 32 to start
rotating, the fan 32 generates air flows traveling from above the
fan 32 radially outwardly of the fan 32. Thus, air flows which
travel from the air inlet 211 into the upper-side flow passage 42
and the lower-side flow passage 43 through the first communicating
passages 421 and 431 are generated in the fan accommodating portion
41. The air flows then pass through the first silencing chambers
422 and 432, the second communicating passages 423 and 433, and the
second silencing chambers 424 and 434, and are discharged out of
the motor module 10 through the air outlets 212.
[0045] The first silencing chamber 422 is arranged to have a flow
passage cross-sectional area greater than that of the first
communicating passage 421. Thus, the first communicating passage
421 and the first silencing chamber 422 together define a first
expansion-type silencer 401. In addition, the second silencing
chamber 424 is arranged to have a flow passage cross-sectional area
greater than that of the second communicating passage 423. Thus,
the second communicating passage 423 and the second silencing
chamber 424 together define a second expansion-type silencer 402.
With the two expansion-type silencers 401 and 402 being arranged
between the fan 32 and the air outlets 212 in the upper-side flow
passage 42 as described above, noise generated in the fan 32 can be
reduced with high efficiency.
[0046] In the present preferred embodiment, the first bend portion
612 of the upper-side first partitioning portion 61 contributes to
increasing the axial dimension of the first communicating passage
421. An increase in a duct length of the first communicating
passage 421 contributes to an improved silencing effect of the
first expansion-type silencer 401 defined by the first
communicating passage 421 and the first silencing chamber 422. In
addition, the length of the first communicating passage 421 can be
adjusted by appropriately adjusting the length of the first bend
portion 612. It is therefore possible to fine-tune the silencing
effect of the first expansion-type silencer 401 to achieve improved
silencing performance.
[0047] In addition, a portion of the first communicating passage
421 is arranged in the first silencing chamber 422, so that the
first expansion-type silencer 401 serves as a silencer with an
inner duct. Specifically, a space over the upper-side motor
covering portion 511 and under the first bend portion 612 performs
a function as an inner duct. Accordingly, this space functions as a
side branch silencer (i.e., an interference/resonance silencer). It
is therefore possible to fine-tune the silencing effect of the
first expansion-type silencer 401 to achieve improved silencing
performance.
[0048] Meanwhile, the second bend portion 622 of the upper-side
second partitioning portion 62 contributes to increasing the axial
dimension of the second communicating passage 423. An increase in a
duct length of the second communicating passage 423 contributes to
an improved silencing effect of the second expansion-type silencer
402 defined by the second communicating passage 423 and the second
silencing chamber 424. In addition, the length of the second
communicating passage 423 can be adjusted by appropriately
adjusting the length of the second bend portion 622. It is
therefore possible to fine-tune the silencing effect of the second
expansion-type silencer 402 to achieve improved silencing
performance.
[0049] In addition, a portion of the second communicating passage
423 is arranged in the second silencing chamber 424, so that the
second expansion-type silencer 402 serves as a silencer with an
inner duct. Specifically, a space under the inner wall of the upper
portion of the body portion 21 and over the second bend portion 622
performs a function as an inner duct. Accordingly, this space
functions as a side branch silencer. It is therefore possible to
fine-tune the silencing effect of the second expansion-type
silencer 402 to achieve improved silencing performance.
[0050] In the lower-side flow passage 43, which is similar to the
upper-side flow passage 42, the first communicating passage 431 and
the first silencing chamber 432 together define an expansion-type
silencer, and the second communicating passage 433 and the second
silencing chamber 434 together define another expansion-type
silencer. With the two expansion-type silencers being arranged
between the fan 32 and the air outlets 212 on the lower side in the
lower-side flow passage 43 as described above, noise generated in
the fan 32 can be reduced with high efficiency.
[0051] In the present preferred embodiment, the first communicating
passage 421 is arranged along the inner wall of the upper portion
of the body portion 21. This allows an air flow generated in the
fan accommodating portion 41 by the fan 32 and traveling radially
outward to easily enter into the first communicating passage 421.
In addition, the second communicating passage 423 is arranged along
the motor 31. Thus, the first and second communicating passages 421
and 423 are arranged at different positions when viewed in the
axial direction. Arranging the first and second communicating
passages 421 and 423 at different positions when viewed in the
axial direction contributes to an improved silencing effect of the
first expansion-type silencer 401 defined by the first
communicating passage 421 and the first silencing chamber 422. That
is, the motor module 10 as a whole is designed with a high priority
placed on the silencing performance.
[0052] Referring to FIG. 3, in the present preferred embodiment,
the casing 20 includes the first casing 71, which is defined by a
single monolithic member, and a second casing 72 defined by a
single monolithic member. The first and second casings 71 and 72
include contact surfaces 710 and 720, respectively, which are
arranged to be in contact with each other on a plane 90 passing
through the rotation axis 9. The casing 20 is arranged to be
substantially symmetrical with respect to the plane 90.
Accordingly, the handle portion 22 is also substantially
symmetrical with respect to the plane 90.
[0053] As described above, the casing 20 includes two members each
of which forms a half of the casing 20, and this contributes to
improving efficiency with which parts of the motor module 10 are
fitted together in a process of manufacturing the motor module 10.
In addition, in the first and second casings 71 and 72, each of
which forms the half of the casing 20, each of the partitioning
portions 61 to 64 is arranged to be perpendicular to the plane 90.
This contributes to reducing the number of mold parts which are
used when the first and second casings 71 and 72 are defined by
injection molding processes. This in turn leads to a reduced
production cost.
[0054] In the present preferred embodiment, each of the upper-side
first partitioning portion 61 and the lower-side first partitioning
portion 63 is defined by a member defined separately from the first
and second casings 71 and 72. When the motor module 10 is
assembled, the upper-side first partitioning portion 61 and the
lower-side first partitioning portion 63 are inserted into the
middle wall portion 53 of each of the first and second casings 71
and 72.
[0055] The first casing 71 includes first projecting portions 711
each of which is arranged to project from the plane 90 toward the
second casing 72. The second casing 72 includes first recessed
portions 721 each of which is recessed from the plane 90. Each
first projecting portion 711 is fitted into a corresponding one of
the first recessed portions 721. The first and second casings 71
and 72 are thus securely fixed to each other. The first projecting
portions 711 and the first recessed portions 721 are arranged in
the vicinity of an outer surface of the casing 20 and around the
handle hole 221.
[0056] In addition, referring to FIG. 4, the first casing 71
includes second recessed portions 712 each of which is recessed
from the plane 90. The second casing 72 includes second projecting
portions (not shown) each of which is arranged to project from the
plane 90 toward the first casing 71. Each second projecting portion
is fitted into a corresponding one of the second recessed portions
712. The first and second casings 71 and 72 are thus more securely
fixed to each other.
[0057] FIG. 5 is a sectional view of a motor module 10A according
to a modification of the first preferred embodiment. In the motor
module 10A according to the modification illustrated in FIG. 5, the
number of air outlets 212A provided for an upper-side flow passage
42A is different from the number of air outlets 212A provided for a
lower-side flow passage 43A. As described above, in the case where
a flow passage 40A is arranged to branch out into the upper-side
flow passage 42A and the lower-side flow passage 43A on the
downstream side of a fan 32A, a different number of air outlets
212A may be provided for each of the upper-side flow passage 42A
and the lower-side flow passage 43A.
[0058] FIG. 6 is a sectional view of a motor module 10B according
to another modification of the first preferred embodiment. In the
motor module 10B according to the modification illustrated in FIG.
6, a second plate portion 621B of an upper-side second partitioning
portion 62B is arranged to slant with respect to the axial
direction. Similarly, a second plate portion 641B of a lower-side
second partitioning portion 64B is also arranged to slant with
respect to the axial direction.
[0059] As illustrated in FIG. 6, each partitioning portion may be
modified in angle and length as desired. This allows silencing
effects of a first expansion-type silencer and a second
expansion-type silencer arranged in each flow passage to be
adjusted to achieve improved silencing performance.
[0060] FIG. 7 is a sectional view of a motor module 10C according
to yet another modification of the first preferred embodiment. In
the motor module 10C according to the modification illustrated in
FIG. 7, an upper-side second partitioning portion 62C includes only
a second plate portion 621C arranged to extend substantially
perpendicularly to the axial direction. In other words, the
upper-side second partitioning portion 62C includes no second bend
portion extending from the second plate portion 621C to the second
axial side. Thus, a duct length of a second communicating passage
423C is equal to a thickness of the upper-side second partitioning
portion 62C. In addition, a lower-side second partitioning portion
64C is arranged to have a shape similar to that of the upper-side
second partitioning portion 62C.
[0061] As illustrated in FIG. 7, each partitioning portion may not
include a bend portion to increase the duct length of a
corresponding communicating passage. The first and second
expansion-type silencers can exhibit silencing performance even
when each of the first and second communicating passages has a
short duct length as described above.
[0062] FIG. 8 is a sectional view of a motor module 10D according
to yet another modification of the first preferred embodiment. In
the motor module 10D according to the modification illustrated in
FIG. 8, each of a first communicating passage 421D and a second
communicating passage 423D is arranged along an inner wall of a
body portion 21D. In addition, the first and second communicating
passages 421D and 423D are arranged to overlap at least in part
with each other when viewed in the axial direction.
[0063] This allows an air flow generated by a fan 32D and traveling
to the second axial side along the inner wall of the body portion
21D to easily enter into the first communicating passage 421D and
the second communicating passage 423D. That is, a reduction in flow
passage resistance in an upper-side flow passage 42D can be
achieved. This leads to improved air blowing efficiency of the
motor module 10D as a whole.
[0064] Note that, although the fan is a centrifugal fan in each of
the above-described preferred embodiment and the modifications
thereof, this is not essential to the present invention. Fans used
in motor modules and vacuum cleaners according to other preferred
embodiments of the present invention may be mixed flow fans.
[0065] Note that, although the flow passage is arranged to branch
out into two flow passages on the downstream side of the fan in
each of the above-described preferred embodiment and the
modifications thereof, this is not essential to the present
invention. Alternatively, only one flow passage may be provided on
the downstream side of the fan. In this case, this sole flow
passage may be an annular flow passage extending all the way around
the motor in the circumferential direction. Also note that the flow
passage may alternatively be arranged to branch out into three or
more flow passages on the downstream side of the fan.
[0066] Note that, although the vacuum cleaner according to the
above-described preferred embodiment is a handy-type vacuum
cleaner, this is not essential to the present invention. Motor
modules according to other preferred embodiments of the present
invention may be installed in an upright-type or stick-type vacuum
cleaner which is arranged to cause gas to be sucked into an air
inlet through a suction head and a dust separation portion and be
discharged through an air outlet, as is the case with the
handy-type vacuum cleaner.
[0067] Also note that a motor module according to a preferred
embodiment of the present invention may be installed in a so-called
canister-type vacuum cleaner. The canister-type vacuum cleaner
includes, in addition to a suction head and a dust separation
portion, a hose portion arranged to join the suction head and the
dust separation portion to each other. The motor module is arranged
to cause gas to be sucked into an air inlet through the suction
head, the hose portion, and the dust separation portion and be
discharged through an air outlet.
[0068] Also note that the detailed shape of any member may be
different from the shape thereof as illustrated in the accompanying
drawings of the present application. For example, the shape of any
of the air inlet, the air outlets, and the wall portions may be
different from that according to each of the above-described
preferred embodiment and the modifications thereof. Also note that
features of the above-described preferred embodiment and the
modifications thereof may be combined appropriately as long as no
conflict arises.
[0069] Preferred embodiments of the present invention are
applicable to, for example, motor modules and vacuum cleaners.
[0070] While preferred embodiments of the present invention have
been described above, it is to be understood that variations and
modifications will be apparent to those skilled in the art without
departing from the scope and spirit of the present invention. The
scope of the present invention, therefore, is to be determined
solely by the following claims.
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