U.S. patent application number 14/813787 was filed with the patent office on 2016-02-11 for electric compressor.
This patent application is currently assigned to KABUSHIKI KAISHA TOYOTA JIDOSHOKKI. The applicant listed for this patent is KABUSHIKI KAISHA TOYOTA JIDOSHOKKI. Invention is credited to Hiroshi FUKASAKU.
Application Number | 20160040674 14/813787 |
Document ID | / |
Family ID | 55135041 |
Filed Date | 2016-02-11 |
United States Patent
Application |
20160040674 |
Kind Code |
A1 |
FUKASAKU; Hiroshi |
February 11, 2016 |
ELECTRIC COMPRESSOR
Abstract
An electric compressor includes a compression part, a motor that
drives the compression part, a cylindrical housing that
accommodates therein the compression part and the motor, a
supporting member, and a first vibration damper. The supporting
member supports the housing and is configured to be fixed to a
target to which the compressor is attached. The first vibration
damper is disposed between the housing and the supporting member so
as to keep the housing free from contact with the supporting member
and the target. The first vibration damper has therein a hollow
enclosed space.
Inventors: |
FUKASAKU; Hiroshi;
(Aichi-ken, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KABUSHIKI KAISHA TOYOTA JIDOSHOKKI |
Kariya-shi |
|
JP |
|
|
Assignee: |
KABUSHIKI KAISHA TOYOTA
JIDOSHOKKI
Kariya-shi
JP
|
Family ID: |
55135041 |
Appl. No.: |
14/813787 |
Filed: |
July 30, 2015 |
Current U.S.
Class: |
417/363 |
Current CPC
Class: |
F04C 2270/12 20130101;
F01C 21/007 20130101; F04C 18/0207 20130101 |
International
Class: |
F04C 29/06 20060101
F04C029/06; F04C 29/00 20060101 F04C029/00; F04C 18/02 20060101
F04C018/02 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 5, 2014 |
JP |
2014-159408 |
Claims
1. An electric compressor comprising: a compression part; a motor
that drives the compression part; a cylindrical housing that
accommodates therein the compression part and the motor; a
supporting member that supports the housing and is configured to be
fixed to a target to which the compressor is attached; a first
vibration damper that is disposed between the housing and the
supporting member; wherein the first vibration damper keeps the
housing free from contact with the supporting member and the
target, and the first vibration damper has therein a hollow
enclosed space.
2. The electric compressor according to claim 1, wherein the first
vibration damper has an annular shape that extends around a
periphery of the housing.
3. The electric compressor according to claim 1, wherein the
supporting member has an annular shape that extends around a
periphery the housing.
4. The electric compressor according to claim 3, wherein an inner
periphery of the supporting member is configured such that an outer
periphery of the first vibration damper is fixed thereon.
5. The electric compressor according to claim 1, wherein the
electric compressor comprises a plurality of the supporting
members, and each of the supporting members is non-annular shaped
and disposed around the housing.
6. The electric compressor according to claim 5, wherein inner
peripheries of the supporting members are configured such that the
outer periphery of the first vibration damper is fixed thereon.
7. The electric compressor according to claim 2, wherein the first
vibration damper is at least at a part thereof in contact with both
of the housing and the target, and the first vibration damper keeps
the housing free from contact with the target.
8. The electric compressor according to claim 1, wherein the first
vibration damper is disposed between the housing and the target,
and the first vibration damper keeps the housing free from contact
with the target.
9. The electric compressor according to claim 1, wherein the first
vibration damper is filled with a gas or a liquid, and the first
vibration damper is configured such that the gas or the liquid is
injectable thereinto.
10. The electric compressor according to claim 9, wherein the gas
is air.
11. The electric compressor according to claim 1, wherein a recess
is formed in one of the outer periphery of the first vibration
damper and the inner periphery of the supporting member, a
projection is formed in the other of the outer periphery of the
first vibration damper and the inner periphery of the supporting
member, and the recess and the projection are adapted to be fitted
to each other.
12. The electric compressor according to claim 11, wherein the
electric compressor further comprises an auxiliary vibration damper
disposed between the first vibration damper and the supporting
member, the auxiliary vibration damper is contactable with the
housing when the first vibration damper is deformed, and the
auxiliary vibration damper keeps the housing free from contact with
the supporting member and the target when the first vibration
damper is deformed.
13. The electric compressor according to claim 1, wherein a groove
is provided in an outer periphery of the housing, and the first
vibration damper is fitted in the groove.
14. An electric compressor comprising: a compression part; a motor
that drives the compression part; a cylindrical housing that
accommodates therein the compression part and the motor; a
supporting member that supports the housing and is configured to be
fixed to a target to which the compressor is attached; and a second
vibration damper that extends along an outer periphery of the
housing and is disposed between the housing and the supporting
member, wherein the second vibration damper keeps the housing free
from contact with the supporting member, when the second vibration
damper is taken along a plane that is perpendicular to the
extending direction of the second vibration damper, the second
vibration damper has a C-shaped cross section with an opening that
is opened toward a side that is opposite to the housing in the
radial direction of the cross section, and the supporting member
covers the opening in an air-tight and liquid-tight manner to seal
a space enclosed by the supporting member and the second vibration
damper.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to an electric compressor.
[0002] Japanese Unexamined Patent Application Publication No.
2013-224652 discloses a cylindrical electric compressor adapted for
use in a vehicle air conditioner. The electric compressor includes
a housing, two supporting members, and a vibration damper. The
housing has therein a motor and a compression part that is driven
by the motor. The supporting members are formed in a
semi-cylindrical shape and support the housing by holding the
housing on the periphery thereof. The supporting members are fixed
to any part or target in the engine compartment of the vehicle
(e.g. a vehicle frame or the engine). In other words, the housing
is fixed to the target via the supporting members. The vibration
damper is disposed between each of the supporting members and the
housing so that the supporting members and the housing are not in
direct contact with each other.
[0003] According to the configuration of the electric compressor
disclosed in Japanese Unexamined Patent Application Publication No.
2013-224652, the vibration damper prevents transmission of
vibration from the compression part and the motor in the electric
compressor to the engine. However, the vibration damper used in the
electric compressor disclosed in the Publication is formed of a
solid rubber. Heat is generated relatively easily in such solid
rubber due to vibration and, therefore, the durability of the
heated vibration damper is lowered, which may lead to poor
vibration damping property.
[0004] The present invention is directed to providing an electric
compressor that prevents the transmission of vibration from the
housing to the target to which the housing of the compressed is
attached.
SUMMARY OF THE INVENTION
[0005] In accordance with an aspect of the present invention, there
is provided an electric compressor that includes a compression
part, a motor that drives the compression part, a cylindrical
housing that accommodates therein the compression part and the
motor, a supporting member, and a first vibration damper. The
supporting member supports the housing and is configured to be
fixed to a target to which the compressor is attached. The first
vibration damper is disposed between the housing and the supporting
member. The first vibration damper keeps the housing free from
contact with the supporting member and the target. The first
vibration damper has therein a hollow enclosed space.
[0006] In an electric compressor according to an aspect of the
present invention, the first vibration damper is disposed between
the housing and the supporting member so as to keep the housing
free from contact with the supporting member and, therefore, the
first vibration damper prevents transmission of vibration of the
housing to the target through the supporting member. The housing
and the target are not in contact with each other, so that direct
transmission of the vibration from the housing to the target is
prevented. The first vibration damper is formed hollow.
Specifically, the first vibration damper has therein a space that
is enclosed and sealed from the exterior thereof. Selecting a
material for filling the hollow space of the first vibration damper
that is less heat-generative under vibration than the material of
the first vibration damper further prevents heat generation due to
the vibration, as compared with the vibration damper that is formed
solid. Therefore, the durability of the first vibration damper
against the heat is improved and the transmission of vibration from
the housing to the target is effectively prevented.
[0007] Other aspects and advantages of the invention will become
apparent from the following description, taken in conjunction with
the accompanying drawings, illustrating by way of example the
principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a longitudinal sectional view of an electric
compressor according to a first embodiment of the present invention
cut along an axis of the housing;
[0009] FIG. 2 is a transverse sectional view taken along line II-II
of FIG. 1;
[0010] FIG. 3 is a longitudinal sectional view showing the electric
compressor of FIG. 1 and a pair of assemblies each including a
supporting member and a vibration damper that is yet to be inflated
with air before being mounted to the housing of the electric
compressor;
[0011] FIG. 4 is a longitudinal sectional view of the electric
compressor with the paired assemblies of FIG. 3 mounted in place on
the housing of the electric compressor;
[0012] FIG. 5 is a transverse sectional view of an electric
compressor according to a first modification of the present
invention;
[0013] FIG. 6 is a transverse sectional view of an electric
compressor according to a second modification of the present
invention, showing a state in which the air pressure of the
vibration dampers is maintained in a specified range;
[0014] FIG. 7 is a transverse sectional view of the electric
compressor according to the second modification of the present
invention, showing a state in which the air pressure of one of the
vibration dampers is below the specified range;
[0015] FIG. 8A is a cross-sectional view of one of the vibration
dampers and the vicinity thereof, taken along line VIIIA-VIIIA of
FIG. 6;
[0016] FIG. 8B is a cross-sectional view of one of the vibration
dampers and the vicinity thereof, taken along line VIIIB-VIIIB of
FIG. 7;
[0017] FIG. 9 is a transverse sectional view of an electric
compressor according to a second embodiment of the present
invention;
[0018] FIG. 10 is a transverse sectional view of an electric
compressor according to a third modification of the present
invention;
[0019] FIG. 11 is a transverse sectional view of an electric
compressor according to a third embodiment of the present
invention;
[0020] FIG. 12 is a transverse sectional view of an electric
compressor according to a fourth modification of the present
invention;
[0021] FIG. 13 is a transverse sectional view of an electric
compressor according to a fourth embodiment of the present
invention;
[0022] FIG. 14 is a transverse sectional view of an electric
compressor according to a fifth modification of the present
invention; and
[0023] FIG. 15 is a cross-sectional view of a vibration damper and
a supporting member of an electric compressor according to a fifth
embodiment of the present invention.
[0024] The following will describe major features of the
embodiments described hereinafter. It is to be noted that technical
elements described hereafter are all independent and exhibit a
technical significance when used alone or in various combinations,
and the combinations of such technical elements are not limited to
those described herein.
DETAILED DESCRIPTION OF THE EMBODIMENTS
First Embodiment
[0025] A first embodiment of the present invention will now be
described with reference to FIGS. 1 to 4. An electric compressor,
which is designated by numeral 10, is mounted to an electric
vehicle or a hybrid car and adapted for use in a vehicle air
conditioner. In FIG. 2, an engine to which the electric compressor
10 is mounted is designated by numeral 60, but in FIGS. 1, 3, and 4
the engine 60 is not illustrated. It is to be noted in the drawings
some cross sections are not indicated by hatching and also that in
FIG. 2 the internal configuration of a housing 12 is not
illustrated. Referring to FIG. 1, the electric compressor 10
includes the housing 12 of a substantially cylindrical shape, a
rotating shaft 39 that is rotatably supported in the housing 12, a
motor including a stator coil 30 and a rotor 34 and a compression
part 22. The motor (30, 34) and the compression part 22 are housed
in the housing 12. The electric compressor further includes a pair
of tubes 50A, 50B that extend around the periphery of the housing
12, and a pair of rims 54A, 54B (see FIG. 2) that support the
housing 12. The rotating shaft 39 extends in the axial direction of
the housing 12 (in the horizontal direction in FIG. 1). The motor
(30, 34) is disposed on one end side the rotating shaft 39 (or the
right hand side in FIG. 1), and the compression part 22 is disposed
on the other end side of the rotating shaft 39. Specifically, the
motor (30, 34) and the compression part 22 are arranged along the
axial direction of the housing 12. The motor (30, 34) supplied with
electric power drives the rotating shaft 39, which in turn drives
the compression part 22. Although not shown in the drawing, the
electric compressor 10 may be equipped with an inverter.
[0026] The housing 12 includes a cylindrical motor housing 16
having a closed end, a front housing 18 that is installed in the
motor housing 16, and a discharge housing 20 that closes the open
end of the motor housing 16 to form an end of the motor housing 16
on the left hand side in FIG. 1.
[0027] The motor housing 16 is made of a metal such as aluminum
alloy. The motor housing includes 16 a peripheral wall and a bottom
wall 16B. The motor housing 16 has through the peripheral wall
thereof a suction port 16A. The suction port 16A is located at a
position adjacent to the bottom wall 16B of the motor housing 16. A
plain bearing 47 that rotatably supports one end of the rotating
shaft 39 (or the right end in FIG. 1) is disposed in the bottom
wall 16B of the motor housing 16.
[0028] The front housing 18 is made of a metal such as aluminum
alloy. The front housing 18 installed in the motor housing 16
separates the interior of the motor housing 16 into a space in
which the motor (30, 34) is disposed and a space in which the
compression part 22 is disposed. A plain bearing 45 is disposed in
the front housing 18 for rotatably supporting the other end of the
rotating shaft 39 (or the left end in FIG. 1).
[0029] The discharge housing 20 has a cylindrical shape with a
closed end and is made of a metal such as aluminum alloy. The
discharge housing 20 has therethrough a discharge port 20A. With
the discharge housing 20 mounted to the motor housing 16, a
discharge chamber 20B is formed between the compression part 22 and
the discharge housing 20. The discharge chamber 20B is communicable
with the outside through the discharge port 20A.
[0030] The rotating shaft 39 is mounted in the housing 12. As
described above, the rotating shaft 39 is rotatably supported at
one end thereof by the plain bearing 47 provided in the motor
housing 16 and at the other end thereof by the plain bearing 45
provided in the front housing 18.
[0031] The motor (30, 34) is disposed on the side of the front
housing 18 that is adjacent to the bottom wall 16B in the motor
housing 16 (or on the right hand side of the front housing 18 in
FIG. 1). The motor (30, 34) includes a rotor 34 fixed on the
rotating shaft 39 and a stator 30 that is disposed raidally outward
of the rotor 34. A coil wire (not shown) is wound around teeth (not
shown) of the stator 30. The motor (30, 34) is electrically
connected to a drive circuit (not shown) and driven by an AC power
supplied from the drive circuit.
[0032] The compression part 22 is disposed in the motor housing 16
on the open end side thereof (on the left side of the front housing
18 in FIG. 1). The compression part 22 includes a fixed scroll 26
fixed to the motor housing 16 and a movable scroll 24 disposed
facing the fixed scroll 26. The fixed scroll 26 and the movable
scroll 24 are engaged with each other in such a way that a
compression chamber 22A is formed therebetween. The volume of the
compression chamber 22A varies with the orbital motion of the
movable scroll 24. The compression chamber 22A is communicable with
the space of the motor housing 16 in which the motor (30, 34) is
disposed and draws in refrigerant gas from the space. The
compression chamber 22A is communicable with the discharge chamber
20B and discharges the compressed refrigerant gas into the
discharge chamber 20B.
[0033] Referring to FIG. 2, the tubes 50A, 50B (only the tube 50A
being shown in the drawing) are formed in a substantially annular
shape around the periphery of the motor housing 16, respectively,
and made of a rubber, such as natural rubber (NB), isoprene rubber
(IR), butadiene rubber (BR), butyl rubber (IIR), ethylene propylene
diene rubber (EPDM), and silicone rubber. As shown in FIGS. 1 and
2, the tubes 50A, 50B are made hollow and the interior of the
respective tubes 50A, 50B is enclosed and sealed from the exterior
thereof. As shown in FIG. 1, the tubes 50A, 50B are provided with
valves 52A, 52B, respectively, and air is injected into and removed
from the tubes 50A, 50B through the valves 52A, 52B, respectively.
In FIGS. 1 and 2, the tubes 50A, 50B are inflated with an
appropriate volume of air and the air pressure is maintained in a
specified range. As shown in FIG. 1, the tubes 50A, 50B have in the
outer periphery thereof (the radially outward surfaces of the tubes
50A, 50B) five grooves 51A, 51B, respectively, formed extending
along the entire circumference of the respective annular tubes 50A,
50B. The grooves 51A, 51B are provided equidistantly in the radial
direction in the cross section of the tubes 50A, 50B in FIG. 1. It
is to be noted that the material of the tubes 50A, 50B is not
limited to rubber, and any other materials such as .alpha.GEL
(registered trademark) may be used. The tubes 50A, 50B correspond
to an example of the first vibration damper of the present
invention and the grooves 51A, 51B correspond to the recesses of
the present invention, respectively.
[0034] The motor housing 16 has in the periphery thereof a pair of
grooves 16C, 16D each extending along the entire circumference of
the motor housing 16. The groove 16C is formed on the motor (30,
34) side with respect to the axial center of the housing 12, and
the groove 16D on the compression part 22 side, respectively.
Imaginary planes passing through the centers of the respective
grooves 16C, 16D are perpendicular to the axis of the housing 12.
Tubes 50A, 50B are fitted along the grooves 16C, 16D, respectively.
The inner diameter of the annular-shaped tubes 50A, 50B having an
internal pressure maintained within the specified range
substantially correspond to the outer diameter of the motor housing
16 as measured at the bottom of the grooves 16C, 16D. The grooves
16C, 16D in the periphery of the motor housing 16 facilitate
positioning of the tubes 50A, 50B. The outer diameters of the motor
housing 16 measured at the positions including the grooves 16C, 16D
are smaller than the outer diameter of the motor housing 16
measured at a position other than the position including the
grooves 16C, 16D. Therefore, the diametric dimension of the
electric compressor 10 measured at the positions where the tubes
50A, 50B are fitted is smaller, as compared with a case in which no
grooves such as 16C, 16D are formed in the periphery of the motor
housing 16 to receive the tubes such as 50A, 50B.
[0035] Referring to FIG. 2, the rims 54A, 54B (only the rim 54A
being shown in the drawing) are formed in a substantially annular
shape around the tubes 50A, 50B, respectively and made of a metal
such as aluminum alloy. As shown in FIG. 1, the rims 54A, 54B are
formed in a substantially arc shape. Specifically, the inner
peripheries of the rims 54A, 54B are curved along the outer
peripheries of the tubes 50A, 50B, respectively. The rims 54A, 54B
have in the inner periphery thereof five projections 56A, 56B
formed extending along the entire circumference of the respective
tubes 50A, 50B. The projections 56A, 56B are spaced equidistantly
in the circumferential direction in the cross section of the
respective tubes 50A, 50B in FIG. 1. The interval of any two
adjacent projections 56A, 56B of the rims 54A, 54B is substantially
the same as the interval of any two adjacent grooves 51A, 51B of
the tubes 50A, 50B, respectively. The width and the height of the
projections 56A, 56B are substantially the same as the width and
the depth of the grooves 51A, 51B. The inner diameters of the rims
54A, 54B are substantially the same as the outer diameter of the
tubes 50A, 50B, respectively, so that the projections 56A, 56B of
the rims 54A, 54B are fitted in the grooves 51A, 51B of the tubes
50A, 50B, respectively, thereby preventing the tubes 50A, 50B from
being displaced from the rims 54A, 54B, respectively. The tubes
50A, 50B are disposed between the motor housing 16 and the rims
54A, 54B, respectively. When the air pressure of the tubes 50A, 50B
is maintained within the specified range, the tubes 50A, 50B are in
close contact with the motor housing 16 and the rims 54A, 54B,
respectively. As shown in FIG. 1, because the tubes 50A, 50B are
disposed between the rims 54A, 54B and the motor housing 16, the
rims 54A, 54B are not in contact with the motor housing 16. It is
to be noted that the rims 54A, 54B correspond to an example of the
supporting member of the present invention, and the projections
56A, 56B correspond to an example of the projections of the present
invention.
[0036] As shown in FIG. 1, the rims 54A, 54B have at the top and
bottom thereof mountings 58A, 58B of a flat plate shape,
respectively. Each of the mountings 58A, 58B has wider surfaces
that are parallel to the axial direction of the housing 12. As
shown in FIG. 2, the engine 60 has two mounting projections 62
projecting one above the other from a side of the engine 60. The
projections 62 extend in the direction away from the viewer of FIG.
2, or extend axially along the housing 12. Each projection 62
extends to such an extent that end surface of the projection 62
(the left surface in FIG. 2) is in contact with one of the wide
surfaces of the mountings 58A, 58B (the right surface in FIG. 2),
respectively. The mountings 58A, 58B are fastened to the ends of
the projections 62 by bolts 64 to thereby fix the rims 54A, 54B to
the engine 60. The housing 12 thus supported by the rims 54A, 54B
is fixed to the engine 60. The rims 54A, 54B that extend around the
periphery of the motor housing 16 firmly support the housing 12. A
part of the housing 12 (the right part of the housing 12 in FIG. 2)
is located in the recessed space formed by a surface of the engine
60 and the projections 62. As shown in FIG. 2, the rims 54A, 54B
are in contact only at the mountings 58A, 58B thereof with the
engine 60. It is to be noted that the engine 60 corresponds to an
example of the target of the present invention to which the
electric compressor is attached.
[0037] A procedure for assembling the tubes 50A, 50B and the rims
54A, 54B to the motor housing 16 will now be described with
reference to FIGS. 3 and 4. First, the rims 54A, 54B and the tubes
50A, 50B from which air is removed (that is, the air pressure of
the tubes 50A, 50B is below the specified range) are prepared.
Next, the tubes 50A, 50B are assembled to the rims 54A, 54B by
fitting the projections 56A, 56B of the rims 54A, 54B into grooves
51A, 51B of the tubes 50A, 50B, respectively. Since the tubes 50A,
50B are made of an elastic rubber, the engagement of the grooves
51A, 51B and the projections 56A, 56B prevents the tubes 50A, 50B
from being moved off from the rims 54A, 54B by virtue of the
friction occurring therebetween. With the engagement, the outer
periphery of the tubes 50A, 50B are fixed to the inner periphery of
the rims 54A, 54B, respectively, thus the tubes 50A, 50B and the
rims 54A, 54B being integrated. In the following description, the
tubes 50A, 50B that are fixed to the rims 54A, 54B will also be
referred to as tube assemblies 55A, 55B.
[0038] Subsequently, the tube assembly 55A is fitted over the
periphery of the motor housing 16 by mounting the bottom wall 16B
thereof and installed in the groove 16D (see FIG. 4). Then the tube
assembly 55B is fitted in the same manner over the periphery of the
motor housing 16 by mounting from the discharge housing 20 side and
fitted in the groove 16C (see FIG. 4). Air has been removed from
the tubes 50A, 50B at the time of assembling the tube assemblies
55A, 55B onto the motor housing 16, the inner diameter of the
respective annular tubes 50A, 50B is greater than the outer
diameter of the housing 12 (specifically, the outer diameter of the
housing 12 measured at positions other than the grooves 16C, 16D).
Accordingly, it is easy for the tube assemblies 55A, 55B to be fit
over the motor housing 16.
[0039] Subsequently, the tubes 50A, 50B are inflated by injecting
air through the valves 52A, 52B, respectively. Air is injected
until the air pressure of the tubes 50A, 50B reaches a value in the
specified range. By so doing, the tubes 50A, 50B are inflated to
expand radially inwardly (or toward the housing 12) and to be
brought into contact with the surfaces of the grooves 16C, 16D,
respectively to be elastically deformed. In other words, the tubes
50A, 50B exerts elastic force acting radially inwardly against the
motor housing 16. The tubes 50A, 50B are made of a rubber material.
Therefore, the tubes 50A, 50B thus inflated to be in contacted with
the respective grooves 16C, 16D, are held in place in the grooves
16C, 16D and the displacement of the tubes 50A, 50B is prevented by
virtue of the friction occurring between the tubes 50A, 50B and the
grooves 16C, 16D. Thus the tube assemblies 55A, 55B are assembled
to the motor housing 16. Because the tubes 50A, 50B and the rims
54A, 54B are thus integrated together into a single structure,
respectively, assembly of the tubes 50A, 50B and the rims 54A, 54B
to the motor housing 16 can be performed at a time, simplifying the
assembling procedure. Subsequently, the mountings 58A, 58B of the
rims 54A, 54B are fixed to the engine 60 by bolts 64, with the
result that the housing 12 supported by the rims 54A, 54B is fixed
to the engine 60. It is to be noted that the tubes 50A, 50B may be
inflated after the rims 54A, 54B are fixed to the engine 60.
[0040] The operation of the electric compressor 10 will now be
described. The motor (30, 34) supplied with electric power from a
drive circuit (not shown) dives the rotating shaft 39 with the
motor (30, 34). With the rotation of the rotating shaft 39, the
movable scroll 24 orbits and the volume of the compression chamber
22A of the compression part 22 varies with the orbiting motion of
the movable scroll 24. Refrigerant gas introduced through the
suction port 16A flows in the motor housing 16 in the axial
direction thereof and then is taken into the compression chamber
22A of the compression part 22. The refrigerant gas is compressed
in the compression chamber 22A with the orbiting motion of the
movable scroll 24. The compressed refrigerant gas is sent to the
discharge chamber 20B and is discharged to the outside of the
housing 12 through the discharge port 20A. The air pressure of the
tubes 50A, 50B is checked periodically and air is added as
appropriate through the valves 52A, 52B. The air pressure of the
tubes 50A, 50B is maintained within the specified range so that the
desired vibration damping of the 50A, 50B is maintained for a
prolonged period of time.
[0041] In the electric compressor 10, the tubes 50A, 50B are
disposed between the motor housing 16 and the rims 54A, 54B,
respectively, so that the motor housing 16 and the rims 54A, 54B
are not in contact with each other because of the intervention of
the tubes 50A, 50B. The tubes 50A, 50B prevent transmission of
vibration of the compression part 22 and the motor (30, 34) to the
engine 60 through the rims 54A, 54B and the motor housing 16 (or
the housing 12). The tubes 50A, 50B also prevent transmission of
vibration of the engine 60 to the housing 12. The tubes 50A, 50B,
which are formed hollow and filled with air, prevent heat
generation due to the vibration effectively as compared with the
solid tubes. Thus, deterioration of the durability of the tubes
50A, 50B against the heat is improved and the desired vibration
damping between the housing 12 and the engine 60 is maintained for
a long period of time.
[0042] In the electric compressor 10, the tubes 50A, 50B, which are
formed in a substantially annular shape, may be set correctly in
place on the periphery of the motor housing 16. Particularly in the
present embodiment, the tubes 50A, 50B which are formed of elastic
rubber and fitted around the entire periphery of the motor housing
16 may be prevented from being displaced on the motor housing 16
due to vibration, and the transmission of vibration of the
compression part 22 and the motor (30, 34) to the engine 60 through
the housing 12 may also be prevented successfully, as compared with
the configuration in which the tubes such as 50A, 50B are disposed
only partially on the periphery of the motor housing 16.
[0043] Furthermore, in the electric compressor 10 in which the
tubes 50A, 50B and the rims 54A, 54B are fixed to each other by
fitting the projections 56A, 56B of the rims 54A, 54B in the
grooves 51A, 51B of the tubes 50A, 50B, respectively, the
displacement of the tubes 50A, 50B relative to the rims 54A, 54B
may be prevented. Therefore, the position of the tubes 50A, 50B
relative to the rims 54A, 54B and the non-contact state between the
rims 54A, 54B and the motor housing 16 will not be influenced by
any vibration of the rims 54A, 54B transmitted from the engine 60
or by any vibration of the motor housing 16.
First Modification
[0044] A first modification of the present invention will now be
described with reference to FIG. 5. In the following description of
the first modification, only the differences form the first
embodiment will be described and the detailed description on the
configurations that are common to the first embodiment will be
omitted. This also applies to other embodiments and modifications
unless otherwise specified. It is to be noted that the internal
configuration of the housing 12 is not illustrated in FIG. 5. This
also applies to FIGS. 6 and 7, and FIGS. 9 to 14. In the first
modification, substantially the same tube assemblies each including
a tube and a rim are fitted in the respective grooves 16C, 16D of
the motor housing 16. This also applies to other embodiments and
modifications which will be described hereinafter.
[0045] The first modification of FIG. 5 is different from the first
embodiment in the configuration of the tube. Specifically, the
first modification differs from the first embodiment in that,
unlike the substantially annular-shaped tube 50A, two substantially
arc-shaped tubes 150A, 152A are disposed between the rim 54A and
the motor housing 16. The tubes 150A, 152A are hollow and the
interior of the respective tube 150A, 152A are enclosed and sealed
from the exterior thereof. The tubes 150A, 152A are inflated with
an appropriate volume of air and the air pressure of the tubes
150A, 152A is maintained in a specified range. The procedure for
assembling the tubes 150A, 152A, and the rim 54A to the housing 12
is substantially the same as in the first embodiment.
[0046] The configuration according to the first modification
exhibits substantially the same effects as the first embodiment.
The use of two tubes, namely the tubes 150A, 152A, which are
disposed between the motor housing 16 and the rims 54A, 54B,
respectively, makes easy the maintenance of the tubes (the rim 54B
not being illustrated in FIG. 5). Specifically, each of the tubes
150A, 152A is smaller than the annular-shaped tubes 50A, 50B of the
first embodiment, and therefore, when any defect is found in the
tubes 150A, 152A, replacement of the tubes 150A, 152A with a new
arc-shaped tube can be made easily. In addition, the first
modification makes possible replacement of only one of the tubes
having a defect, which reduces cost associated with the tube
replacement. It is to be noted that the number of the tubes
disposed between the motor housing 16 and the rims 54A, 54B is not
limited to two, and three or more tubes may be used in one tube
assembly.
Second Modification
[0047] A second modification of the present invention will now be
described with reference to FIGS. 6 to 8. The second modification
is different from the first modification in that two sheets 70 are
added, i.e. one sheet 70 disposed between the rim 254A and the tube
150A and the other sheet 70 between the rim 254A and the tube 152A.
FIG. 6 shows a state in which the air pressure of the tubes 150A,
152A is maintained within the specified range, and FIG. 7 shows a
state in which some air is released from the tube 152A, so that the
air pressure of the tube 152A falls below the specified range. FIG.
8A is a cross-sectional view of the tube 152A of FIG. 6, and FIG.
8B is a cross-sectional view of the tube 152A of FIG. 7. The cross
sections in FIGS. 8A and 8B are taken along a plane that is
perpendicular to the extending direction of the tube 152A. As shown
in FIG. 6 and FIG. 8A, the sheet 70 that is disposed between the
rim 254A and the tube 152A is in contact with both of the rim 254A
and the tube 152A. The sheet 70 is formed into a substantially arc
shape and made of a rubber, such as EPDM and silicone rubber. The
sheet 70 is solid and has a C-shaped cross section. The sheet 70 is
disposed extending partially around the outer periphery of the tube
152A. As shown in FIGS. 8A and 8B, the sheet 70 has in the outer
periphery thereof three grooves 71 formed extending along the
circumference of the respective tubes 150A, 152A (in the direction
in which the sheet 70 extends). The rim 254 has in the inner
periphery thereof three projections 256A at positions corresponding
to the respective grooves 71 of the sheet 70. Each projection 256A
is fitted in its corresponding groove 71. As shown in FIG. 8A, when
the air pressure of the tube 152A is maintained in the specified
range, opposite ends of the sheet 70 in the circumferential
direction thereof are not in contact with the peripheral surface of
the motor housing 16. It is to be noted that the material of the
sheet 70 is not limited to a rubber, and other materials such as
the .alpha.GEL (registered trademark) may be used. It is to be
noted that the sheet 70 corresponds to an example of the auxiliary
vibration damper of the present invention. The sheet 70 disposed
between the rim 254A and the tube 152A and the sheet 70 disposed
between the rim 254A and the tube 150A have substantially the same
configuration and are disposed in the same manner.
[0048] The following will describe the positional relationship
between the tubes 150A, 152A and the motor housing 16 when the air
pressure of the tube 150A is maintained in the specified range
while the air pressure of the tube 152A is below the specified
range, with reference to FIG. 7. When the air pressure of the tubes
150A, 152A is maintained within the specified range, the tubes
150A, 152A exert an elastic force that acts radially inwardly on
the motor housing 16 (or acting toward a position O1 which is the
axial center of the motor housing 16). As shown in FIG. 7, when
some air is released from the tube 152A, the motor housing 16 is
pressed toward the tube 152A by the elastic force of the tube 150A,
with the result that the motor housing 16 is moved rightward as
viewed in FIG. 7. The moving distance of the motor housing 16
increases with a decrease of the air pressure of the tube 152A.
When the air pressure of the tube 152A falls below the specified
range and the position of the axial center of the motor housing 16
is shifted from O1 to O2, the opposite ends of the sheet 70
disposed on the tube 152A are brought into contact with the outer
peripheral surface of the motor housing 16, as shown in FIG.
8B.
[0049] In the electric compressor according to the second
modification, as the air pressure of the tube 152A lowers with
time, the motor housing 16 is moved toward the tube 152A by the
elastic force of the tube 150A and the opposite ends of the sheet
70 are brought into contact with the outer peripheral surface of
the motor housing 16. The sheet 70 is then in contact with both the
rim 254A and the motor housing 16 and prevents transmission of the
vibration from the housing 12 to the engine 60 through the rim
254A. In other words, even if the air pressure of the tube 152A is
lowered and the vibration damping thereof is lowered accordingly,
the sheet 70 auxiliarily continues to prevent transmission of the
vibration from the housing 12 to the engine 60. Therefore,
transmission of vibration from the housing 12 to the engine 60 is
prevented for a prolonged period of time and the reliability of the
electric compressor itself is enhanced. In the second modification,
the sheet 70 is also disposed on the outer periphery of the tube
150A. When the air pressure of the tube 152A is maintained in the
specified range while the air pressure of the tube 150A is below
the specified range, the motor housing 16 is moved toward the tube
150A and opposite ends of the sheet 70 on the tube 150A are brought
into contact with the outer peripheral surface of the motor housing
16. Thus, transmission of the vibration from the housing 12 to the
engine 60 is prevented.
Second Embodiment
[0050] A second embodiment of the present invention will now be
described with reference to FIG. 9. The second embodiment is
different from the first embodiment in the configuration of the
rims. Specifically, the rim of the second embodiment is formed by a
pair of substantially semi-annular rims 354A, 356A. The rims 354A,
356A have substantially the same shape. The rims 354A, 356A have at
upper and lower positions thereof as viewed in FIG. 9 mountings
358A, 360A of a flat plate shape, respectively. A substantially
annular-shaped rim is formed by connecting the opposite wider
surfaces of the mountings 358A of the rim 354A and their
corresponding opposite wider surfaces of the mountings 360A of the
rim 356A with each other.
[0051] The procedure for assembling the tube 50A and the rims 354A,
356A to the motor housing 16 will be described. The tube 50A from
which air is removed beforehand is fitted over the motor housing 16
from the bottom wall 16B thereof and fitted in place in the groove
16C. Then the tube 50A is inflated by injecting air through a valve
(not shown) until the air pressure of the tube 50A reaches a value
in the specified range. In the second embodiment, the valve is
mounted directly to the tube 50A and not exposed to the outside
through the rim. Next, the rims 354A, 356A are mounted on the outer
periphery of the tube 50A. Specifically, the rims 354A, 356A are
mounted such that the rims 354A, 356A surround the motor housing
16. When the air pressure of the tube 50A is within the specified
range, the outer diameter of the tube 50A is substantially the same
as the diameter of a circle that is formed by the inner periphery
of the rims 354A, 356A as seen in the cross section of FIG. 9. With
the rims 354A, 356A disposed over the tube 50A, the opposite wider
surfaces of the mountings 358A of the rim 354A and their
corresponding opposite wider surfaces of the mountings 360A of the
rim 356A are brought into contact with each other. In the contacted
state, the mountings 358A and the mountings 360A are fixed to the
projections 62 of the engine 60 by bolts 64. The rims 354A, 356A
are connected with each other over the housing 12. The housing 12
supported by the rims 354A, 356A is thus fixed to the engine
60.
[0052] The second embodiment also exhibits substantially the same
effects as the first embodiment. In the second embodiment in which
the tube 50A is fitted in the groove 16C of the motor housing 16
and then inflated with air before the rims 354A, 356A are attached
to the tube 50A, the tube 50A is difficult to be displaced relative
to the motor housing 16. Thus, the tube 50A is not displaced easily
when the rims 354A, 356A are attached to the tube 50A, which
facilitates attaching of the rims 354A, 356A to the tube 50A. If
the tube assembly with the tube 50A that is yet to be inflated with
air is fitted on the motor housing 16, the tube assembly is not
fixed securely to the motor housing 16 at the time when the tube
50A is inflated with air. Therefore, the tube assembly may be
displaced from the specified position on the housing 12 while air
is injected into the tube 50A. According to the configuration of
the second embodiment, however, such displacement of the tube 50A
is prevented and the tube 50A and the rims 354A, 356A can be
assembled properly to the motor housing 16 at the specified
positions thereof. It is to be noted that the number of the rims is
not limited to two, and three or more rims may be used.
Third Modification
[0053] A third modification of the present invention will now be
described with reference to FIG. 10. In the third modification, the
tube assemblies 150A, 152A of the first modification are disposed
between the motor housing 16 and the rims 354A, 356A of the second
embodiment, respectively. The procedure for assembling the tubes
150A, 152A to the motor housing 16 will be described. Firstly, the
tubes 150A, 152A are fixed to the inner periphery of the rims 354A,
356A to thereby form tube assemblies 355A, 357A, respectively. Then
the tube assemblies 355A, 357A are fitted in the groove 16C of the
motor housing 16 such that the tube assemblies 355A, 357A surround
the motor housing 16. Secondly, with wider surfaces of the
mountings 358A of the tube assembly 355A and the wider surfaces of
the mountings 360A of the tube assembly 357A being in contact with
each other, the mountings 358A and 360A are fixed together to the
projections 62 of the engine 60 by the bolts 64, and then air is
injected into the tubes 150A, 152A.
[0054] The third modification also exhibits substantially the same
effects as the first embodiment. Furthermore, in the third
modification, the tube assemblies 355A, 357A can be fitted directly
in the groove 16C of the motor housing 16. Specifically, there is
no necessity to fit the tube assemblies 355A, 357A over the housing
12 from one end thereof to a specified position on the motor
housing 16 (for example, from the bottom wall 16B of the motor
housing 16 onto the groove 16C). Therefore, the tube assemblies
355A, 357A may be mounted on the housing 12 irrespective of the
contour of the housing 12, which does not lower the freedom of
design of the housing 12. In the case that the tube and the rim are
integrated in a single part of a substantially annular shape, the
maximum outer diameter of the housing 12 between one end of the
housing 12 and a specified position at which the tube assembly is
fitted cannot be made greater than the inner diameter of the tube
assembly, which lowers the freedom of design of the housing 12.
However, the above-described configuration of the third
modification will not lower the freedom of design of the housing
12.
Third Embodiment
[0055] A third embodiment of the present invention will now be
described with reference to FIG. 11. The third embodiment is
different from the first embodiment in that the tube 50A is
disposed between the motor housing 16 and the engine 60.
Specifically, the rim 454A is disposed extending over a part of the
outer periphery of the tube 50A. The rim 454A has at the top and
bottom thereof as viewed in FIG. 11 mountings 458A. The housing 12
is fixed to the engine 60 by fixing the mountings 458A to the
projections 62 of the engine 60 by the bolts 64. The remaining part
of the outer periphery of the tube 50A that is not covered by the
rim 454A is located in a recessed space formed by a surface of the
engine 60 and the two projections 62 of the engine 60. In the
recessed space, the tube 50A is in surface contact with the engine
60 at a part of inner surfaces of the respective projections 62
facing each other and of the bottom of the recessed space. Contact
of the housing 12 with the engine 60 is prevented by the tube 50A
interposed therebetween. The procedure for assembling the tube 50A
and the rim 454A to the motor housing 16 will be described. The
tube 50A is mounted to the inner periphery of the rim 454A to
thereby form a tube assembly 455A, and the tube assembly 455A is
fitted in the groove 16C of the motor housing 16 by mounting the
tube assembly 455A over the motor housing 16 from the bottom wall
16B. Subsequently, the mountings 458A are fixed to the projections
62 of the engine 60 by bolts 64 and the tube 50A is inflated with
air. When the air pressure of the tube 50A reaches a value in the
specified range, the tube 50A is brought into surface contact with
the engine 60 at a part of the inner surfaces of the projections 62
facing each other and the bottom of the recessed space.
[0056] The third embodiment also exhibits substantially the same
effects as the first embodiment. Furthermore, in the third
embodiment in which the tube 50A is brought in contact with the
walls of the engine 60, the housing 12 is supported by the walls of
the engine 60, as well as the rim 454A. According to the
configuration of the third embodiment, the dimension of the rim
454A in the circumferential direction can be reduced and the amount
of materials for manufacturing the rim 454A can accordingly be
reduced, while the firm support for the housing 12 is
maintained.
Fourth Modification
[0057] A fourth modification of the present invention will now be
described with reference to FIG. 12. In the following description
of the fourth modification, only the differences from the third
embodiment will be described and the detailed description on the
configurations that are common to the third embodiment will be
omitted. The fourth modification is different from the third
embodiment in the configuration of the tubes. Specifically, in the
fourth modification, a substantially arc-shaped tube 450A is
disposed between the rim 454A and the motor housing 16 and a
substantially arc-shaped tube 452A is disposed between the engine
60 and the motor housing 16. The tube 452A is in surface contact
with the engine 60 at a part of the inner surfaces of the
respective projections 62 facing each other and the bottom of the
recessed space.
[0058] The procedure for assembling the tubes 450A, 452A and the
rim 454A to the motor housing 16 will be described. The tube 452A
from which air is removed beforehand is fitted in the groove 16C of
the motor housing 16. Specifically, the tube 452A is set in the
right half of the groove 16C of the motor housing 16 as viewed in
the axial direction of the housing 12 from the bottom wall 16B
side, as shown in FIG. 12 (i.e. the right side in the outer
periphery of the motor housing 16 in FIG. 12). Subsequently, the
housing 12 on which the tube 452A is mounted is set in the recessed
space formed between the two projections 62 of the engine 60. Then
the tube 452A is inflated with air. By so doing, the inflated tube
452A is brought into surface contact with the engine 60 at the
aforementioned three parts. The tube 450A is fixed to the inner
periphery of the rim 454A to thereby form a tube assembly and the
tube assembly is fitted in the left part of the groove 16C as
viewed in FIG. 12. The mountings 458A of the rim 454A are fixed to
the engine 60 by the bolts 64, and the tube 450A is inflated by
injecting air thereinto. The fourth modification also exhibits
substantially the same effects as the third embodiment. The tube
450A of the fourth embodiment is relatively short in the
circumferential direction and therefore can be attached to the rim
454A easily. Furthermore, the tube assembly and the tube 452A are
substantially arc shaped and therefore can be fitted directly in
the groove 16C, which does not lower the freedom of design of the
housing 12. It is to be noted that the number of the tubes disposed
between the engine 60 and the motor housing 16 is not limited to
one, and two or more tubes may be used.
Fourth Embodiment
[0059] A fourth embodiment of the present invention will now be
described with reference to FIG. 13. The fourth embodiment is
different from the first embodiment in the configuration of the
rims. Specifically, in the fourth embodiment, two substantially
arc-shaped rims 554A, 556A are disposed on the outer periphery of
the annular tube 50A. The rims 554A, 556A are in the same
circumference of the tube 50A. The rim 554A is disposed at an upper
part of the motor housing 16 and the rim 556A is disposed at a
lower part of the motor housing 16 (i.e. the side opposite to the
rim 554A across the motor housing 16) as viewed in FIG. 13. In
other words, some parts of the outer peripheral surface of the tube
50A of the fourth embodiment are exposed without being covered by
the rims. The rims 554A, 556A have mountings 558A, 560A,
respectively. The mountings 558A, 560A are fixed to the engine 60
by the bolts 64. Thus, the housing 12 supported by the rims 554A,
556A is fixed to the engine 60.
[0060] The procedure for assembling the tube 50A and the rims 554A,
556A will be described. The tube 50A is fixed to the inner
peripheries of the rims 554A, 556A, respectively, to thereby form a
tube assembly 555A. The tube assembly 555A is fitted onto the motor
housing 16 from the bottom wall 16B thereof and is fitted in the
groove 16C. The tube 50A is inflated with air and the mountings
558A, 560A are fixed to the engine 60 by the bolts 64. The fourth
embodiment also exhibits substantially the same effects as the
first embodiment. In the fourth embodiment in which the rims 554A,
556A are disposed on opposite sides of the housing 12, the housing
12 that is held by the rims 554A, 556A from outside is stably
supported. It may be so configured that the exposed part of the
outer periphery of the tube 50A is in contact with the engine
60.
Fifth Modification
[0061] A fifth modification of the present invention will now be
described with reference to FIG. 14. In the fifth modification,
only the differences from the fourth embodiment will be described
and the detailed description on the configurations that are common
to the fourth embodiment will be omitted. The fifth modification is
different from the fourth embodiment in the configuration of the
tube. Specifically, in the fifth modification, a substantially
arc-shaped tube 650A is disposed between the rim 554A and the motor
housing 16 and a substantially arc-shaped tube 652A is disposed
between the rim 556A and the motor housing 16. The tubes 650A, 652A
have substantially the same shape and the length of the tubes 650A,
652A in the circumferential direction is substantially the same as
the length of the rims 554A, 556A in the circumferential direction.
The procedure for assembling the tubes 650A, 652A and the rims
554A, 556A to the motor housing 16 will be described. The tubes
650A, 652A are firstly fixed to the inner periphery of the rims
554A, 556A to thereby form tube assemblies 655A, 657A,
respectively. The tube assemblies 655A, 657A are fitted in the
groove 16C of the motor housing 16 such that the tube assemblies
655A, 657A hold therebetween the motor housing 16. The tubes 650A,
652A are inflated with air and the mountings 558A, 560A of the rims
554A, 556A are fixed to the engine 60 by the bolts 64. The fifth
modification also exhibits substantially the effects as the fourth
embodiment. Furthermore, the tube assemblies 655A, 657A which are
substantially arc shaped and therefore can be fitted directly in
the groove 16C, which does not lower the freedom of design of the
housing 12.
Fifth Embodiment
[0062] A fifth embodiment of the present invention will now be
described with reference to FIG. 15. The fifth embodiment is
different from the first embodiment in the cross-sectional shape
and the configuration of the tube and the rim. Unlike the tube 50A
that is hollow and has a substantially annular cross section, a
tube 750A in the fifth embodiment has a substantially C-shaped
cross section having an opening 700 that is opened toward the side
opposite to the motor housing 16 in the radial direction of the
cross section. The opening 700 is formed extending along the entire
circumference of the tube 750A. A rim 754A covers the opening 700
so that the entire opening 700 is air-tight and liquid-tight. The
tube 750A and the rim 754A form a substantially annular, hollow
tube assembly 755A. The interior of the tube assembly 755A is
enclosed and sealed from the exterior thereof. The tube assembly
755A is filled with air. Air can be injected into the tube assembly
755A through a valve 752A attached to the rim 754A. The air
pressure of the tube assembly 755A can be maintained in the
specified range by refilling the tube assembly 755A periodically
with air. With the air pressure of the tube assembly 755A kept
within the specified range, the motor housing 16 is not in contact
with the rim 754A because of the intervention of the tube 750A. The
assembling procedure of the tube assembly 755A to the motor housing
16 is substantially the same as the first embodiment. It is to be
noted that the tube 750A corresponds to an example of the second
vibration damper of the present invention. The fifth embodiment
also exhibits substantially the same effects as the first
embodiment. Furthermore, the configuration according to the fifth
embodiment requires no projection or groove for fixing the tube
750A to the rim 754A. The configuration according to the fifth
embodiment facilitates manufacturing of the rims 754A and the tubes
750A.
[0063] Although embodiments of the present inventions have been
described in detail, these embodiments are mere examples and the
electric compressor according to the present invention may
variously be modified within the gist of the invention.
[0064] For example, the tubes are filled with air in the above
embodiments and the modifications. However, the configuration of
the tubes is not limited to this.
[0065] The tubes may be filled with any medium that provides
excellent vibration absorbing characteristics and is less
heat-generative under vibration than the material used for the
tubes. Vibration absorbing medium to be used in the tubes includes
a gas such as nitrogen, a liquid such as ethylene glycol or
propylene glycol, a gel, or a resin such as silicone resin.
[0066] The tubes 50A,50B may not necessarily have an annular shape,
and may have an elliptic shape or a rectangular shape in the cross
section as long as the shape conforms to contour of the housing 12.
The housing 12 may not necessarily have a cylindrical shape and may
have an elliptical and cylindrical shape, for example. Furthermore,
the tubes 50A, 50B may not be fitted extending around the
circumferential periphery of the housing 12, and extending on the
periphery of the motor housing 16 in the axial direction thereof
and the opposite longitudinal ends of the housing 12 (i.e. the end
of the discharge housing 20 and the bottom wall 16B of the motor
housing 16).
[0067] The projections 56A, 56B and the grooves 51A, 51B may not
necessarily be formed extending around the entire circumference of
the outer peripheries of the annular rims 54A, 54B and the tubes
50A 50B, respectively, as long as the rims 54A, 54B are kept from
being displaced from the tubes 50A, 50B due to the vibration of the
engine 60. The rims 54A, 54B may be fixed to any other components
than the engine 60, such as any vehicle frame.
[0068] The sheet 70 of the second modification is applicable to the
electric compressor in which two or more substantially arc-shaped
tubes are fitted in the grooves 16C, 16D of the motor housing 16.
Specifically, the sheet 70 may be disposed on the outer periphery
of the tubes in the electric compressor according to the third
modification (FIG. 10), the fourth modification (FIG. 12), and the
fifth modification (FIG. 14). This is also applicable to the tube
452A used in the fourth modification. Additionally, it may be so
configured that the sheet 70 is fixed to the outer periphery of the
tube by engagement of a plurality of grooves that is formed in one
of the sheet 70 and the tube and a plurality of projections that is
formed in the other of the sheet 70 and the tube. The sheet 70 may
not necessarily be disposed on every tube. For example, the sheet
70 may be used only for the tube that allows air to be released
relatively easily or for the tube that tends to deteriorate
relatively easily.
[0069] In the second embodiment, the tube 50A is fitted over the
motor housing 16 and then the rims 354A, 356A are mounted on the
tube 50A. However, the assembling order is not limited to this. The
procedure for assembling may be such that the wider surfaces of the
mountings 358A of the rim 354A and the wider surfaces of the
mountings 360A of the rim 356A are brought into contact with each
other, a tube assembly formed by fixing the tube 50A from which air
is removed beforehand to the inner peripheries of the rims 354A,
356A is mounted on the motor housing 16, the mountings 358A, 360A
are fixed to the engine 60 by bolts 64, and then the tube 50A is
inflated with air.
[0070] Furthermore, in the third modification, the tube assemblies
355A, 357A that are built beforehand are assembled to the motor
housing 16. However, the assembling order is not limited to this.
For example, the procedure for assembling may be such that the
tubes 150A, 152A are fitted in the groove 16C of the motor housing
16 and then inflated with air, the rims 354A, 356A are mounted on
the outer peripheries of the tubes 150A, 152A, and the mountings
358A, 360A are fixed to the engine 60 by the bolts 64.
[0071] In the fourth embodiment, the tube assembly 555A is built
and then assembled to the motor housing 16. However, the assembling
order is not limited to this. For example, the procedure for
assembling may be such that the tube 50A is set on the motor
housing 16 and inflated with air, the rims 554A, 556A are mounted
on the periphery of the tube 50A, and the mountings 558A, 560A are
fixed to the engine 60 by the bolts 64.
[0072] In the fifth embodiment, one tube 750A is disposed between
the rim 754A and the motor housing 16. However, the number of the
tube 750A is not limited to one, and two or more arc-shaped tubes
may be used. In this case, each of the tubes is closed at the
opposite ends thereof in the circumferential direction thereof, and
the space enclosed by the tubes and the rim 754A is sealed from the
exterior thereof.
[0073] Specific embodiments of the present invention have been
described in detail. However, these embodiments are mere examples
and not intended to restrict the scope of the present invention.
The embodiments disclosed herein may variously be modified. The
technical elements described in the specification and the drawings
exhibit the technical significance when used alone or in various
combinations, and therefore should not be limited to the
combinations disclosed herein. The technique exemplified in the
specification and the drawings is to achieve multiple purposes at
the same time, and therefore achieving one of the purposes
constitutes the technical significance.
* * * * *