U.S. patent application number 10/074317 was filed with the patent office on 2002-08-22 for compressor.
Invention is credited to Murase, Masakazu, Yokomachi, Naoya.
Application Number | 20020114709 10/074317 |
Document ID | / |
Family ID | 18904300 |
Filed Date | 2002-08-22 |
United States Patent
Application |
20020114709 |
Kind Code |
A1 |
Murase, Masakazu ; et
al. |
August 22, 2002 |
Compressor
Abstract
A compressor has a front housing, a rear housing, a plurality of
bolts, and a rigid plate. The rear housing is connected to the
front housing. The bolts connect the front housing and the rear
housing in an axial direction. The rigid plate is disposed between
an axial end surface of one of the front and rear housings and
heads of the bolts. The front housing and the rear housing are
connected by the bolts via the rigid plate.
Inventors: |
Murase, Masakazu;
(Kariya-shi, JP) ; Yokomachi, Naoya; (Kariya-shi,
JP) |
Correspondence
Address: |
MORGAN & FINNEGAN, L.L.P.
345 Park Avenue
New York
NY
10154
US
|
Family ID: |
18904300 |
Appl. No.: |
10/074317 |
Filed: |
February 12, 2002 |
Current U.S.
Class: |
417/269 |
Current CPC
Class: |
F04B 27/1081
20130101 |
Class at
Publication: |
417/269 |
International
Class: |
F04B 001/12 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 19, 2001 |
JP |
2001-041927 |
Claims
What is claimed is:
1. A compressor comprising, a front housing; a rear housing
connected to the front housing; a plurality of bolts connecting the
front housing and the rear housing in an axial direction; and a
rigid plate disposed between an axial end surface of one of the
front and rear housings and heads of said bolts; and wherein the
front housing and the rear housing are connected by said bolts via
said rigid plate.
2. The compressor according to claim 1, wherein said rigid plate is
annular in shape, and said bolts are positioned on the
circumference of said rigid plate.
3. The compressor according to claim 2, wherein said rigid plate is
annular in shape, and said bolts are positioned substantially in
equiangular positions on the circumference of said rigid plate.
4. The compressor according to claim 2, wherein said rigid plate is
annular in shape, and said rigid plate is formed in one piece.
5. The compressor according to claim 2, wherein said rigid plate is
annular in shape, and said rigid plate is constituted of a
plurality of plates, and each plate is screwed by a plurality of
bolts.
6. The compressor according to claim 1, wherein said rigid plate is
disk-shaped, and said bolts are positioned on the circumference of
said rigid plate.
7. The compressor according to claim 1, wherein refrigerant gas
used in the compressor is carbon dioxide.
8. The compressor according to claim 1, wherein the compressor is a
swash plate type.
9. The compressor according to claim 1, wherein the compressor is a
variable displacement type.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a compressor and more
particularly to a compressor that suppresses deformation of a
thrust surface receiving thrust force inside a housing of the
compressor.
[0002] FIG. 5 shows a structure of a conventional swash plate type
compressor. A front housing 1 and a rear housing 2 are secured by
bolts 4 via a gasket 3. The front housing 1 and the rear housing 2
constitute a housing 5 of the compressor. A step 6 is formed inside
the front housing 1. A retainer plate 7, a discharge valve plate 8,
a valve plate 9, a suction valve plate 10 are fitted into the front
housing 1, so as to contact with the step 6. A suction chamber 12
and a discharge chamber 13 are defined between the retainer plate 7
and a front end wall 11 of the front housing 1 such that the
suction chamber 12 and the discharge chamber 13 are separated by a
separating wall 14.
[0003] A cylinder block 15 is fitted into the front housing 1 so as
to contact with the suction valve plate 10. The cylinder block 15
is secured to the front housing 1 by bolts 16. A drive shaft 17 is
rotatably supported by the cylinder block 15, the front housing 1
and the rear housing 2. The one end of the drive shaft 17 protrudes
outwardly from the front housing 1, and connects with a driving
source, such as an engine or a motor of a vehicle, which is not
shown. In the rear housing 2, a lug plate 18 as a rotary support
member is secured to the drive shaft 17, and a swash plate 19 is
connected with the lug plate 18. The drive shaft 17 extends through
a through hole, which is formed through the center of the swash
plate 19. A pair of guide pins 20 extending from the swash plate 19
is slidably fitted into a pair of guide holes 21 formed on the lug
plate 18. The swash plate 19 integrally rotates with the drive
shaft 17 by connecting the guide pins 20 and the guide holes 21.
The swash plate 19 is slidably tiltably supported by the drive
shaft 17 so as to slide in an axial direction of the drive shaft
17. The lug plate 18 is rotatably supported by a thrust bearing 22,
which is disposed on an inner wall of the rear end of the rear
housing 2.
[0004] The cylinder block 15 forms a plurality of cylinder bores 23
surrounding the drive shaft 17, and each cylinder bore 23 slidably
accommodates each associated piston 24. Each piston 24 is coupled
to the periphery of the swash plate 19 through a pair of shoes 25.
As the swash plate 19 integrally rotates with the drive shaft 17,
each piston 24 reciprocates in the axial direction of the drive
shaft 17 in the associated cylinder bore 23 through shoes 25.
[0005] However, the bolts 4 connecting the front housing 1 and the
rear housing 2 are arranged in the vicinity of a thrust bearing 22.
As the thrust surface of the inner wall of the rear end of the rear
housing 2 deforms due to the bolts 4, the deformation of the thrust
surface causes an eccentric load to act on the thrust bearing 22.
With a consequence of a noise during an operation of the compressor
and shortened durability of the thrust bearing 22.
[0006] Particularly, when carbon dioxide is used as refrigerant
gas, pressure in the compressor relatively increases. Therefore,
the bolts 4 need to be further firmly fastened. However, in such a
state, the eccentric load tends to act on the thrust bearing
22.
SUMMARY OF THE INVENTION
[0007] The present invention addresses the above-mentioned problems
traceable to an eccentric load by suppressing deformation of a
thrust surface of an inner wall of a housing in a compressor.
[0008] In accordance with the present invention, a compressor has a
front housing, a rear housing, a plurality of bolts, and a rigid
plate. The rear housing is connected to the front housing. The
bolts connect the front housing and the rear housing in an axial
direction. The rigid plate is disposed between an axial end surface
of one of the front and rear housings and heads of the bolts. The
front housing and the rear housing are connected by the bolts via
the rigid plate.
[0009] According to the present invention, since connecting force
of the bolts is equally added on the end surface of one of the
front and rear housings via the rigid plate, deformation of the
thrust surface is inhibited.
[0010] 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 DRAWING
[0011] The features of the present invention that are believed to
be novel are set forth with particularity in the appended claims.
The invention together with objects and advantages thereof, may
best be understood by reference to the following description of the
presently preferred embodiments together with the accompanying
drawings in which:
[0012] FIG. 1 is a longitudinal cross-sectional view of a
compressor according to a first embodiment of the present
invention;
[0013] FIG. 2 is a rear elevation of a compressor illustrated in
FIG. 1;
[0014] FIG. 3 is a rear elevation of a compressor according to a
second embodiment;
[0015] FIG. 4 is a rear elevation of a compressor according to a
third embodiment; and
[0016] FIG. 5 is a longitudinal cross-sectional view of a
compressor of a conventional art.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] A first embodiment of the present invention will now be
described with reference to FIGS. 1 and 2. FIG. 1 shows a structure
of a variable displacement compressor according to the first
embodiment of the present invention. A front housing 1 and a rear
housing 26, which are made of aluminum, are connected via a gasket
3. In this manner, a housing 27 is constructed. A rigid plate 28,
which is made of iron, is annular in shape. The rigid plate 28 is
disposed on the rear end surface of the rear housing 26. The rigid
plate 28 has a bearing surface for bolts 4, and the bolts 4 extends
through the rigid plate 28 and the rear housing 26 and is screwed
on the front housing 1. As shown in FIG. 2, a plurality of bolts 4
is disposed in equiangular positions on an identical circumference.
Thereby, the front housing 1 and the rear housing 26 are connected
in an axial direction of the drive shaft 17.
[0018] Other components of the compressor of the present invention
are similar to those in the conventional art shown in FIG. 5. A
step 6 is formed inside the front housing 1. A retainer plate 7, a
discharge valve plate 8, a suction valve plate 10 and a valve plate
9 are fitted into the front housing so as to contact with the step
6. A suction chamber 12 and a discharge chamber 13 are defined
between the retainer plate 7 and a front end wall 11 of the front
housing 1 such that the suction chamber 12 and the discharge
chamber 13 are separated by a separating wall 14.
[0019] A cylinder block 15 is fitted into the front housing 1 so as
to contact with the suction valve plate 10. The cylinder block 15
is secured to the front housing 1 by bolts 16. A drive shaft 17 is
rotatably supported by the cylinder block 15, the front housing 1
and the rear housing 26. The one end of the drive shaft 17
protrudes outwardly from the front housing 1, and is connected with
a driving source, such as an engine or a motor of a vehicle, which
is not shown in FIG. 4 in the rear housing 26. A lug plate 18 is
secured to the drive shaft 17, and a swash plate 19 is connected
with the lug plate 18. The drive shaft 17 extends through a through
hole, which is formed through the center of the swash plate 19. A
pair of guide pins 20 extending from the swash plate 19 is slidably
fitted into a pair of guide holes 21 formed on the lug plate 18.
The swash plate 19 integrally rotates with the drive shaft 17 by
connecting the guide pins 20 and the guide holes 21. The swash
plate 19 is slidably tiltably supported by the drive shaft 17 so as
to slide in an axial direction of the drive shaft 17. The lug plate
18 is rotatably supported by a thrust bearing 22, which is disposed
on an inner wall of the rear end of the rear housing 26.
[0020] The cylinder block 15 forms a plurality of cylinder bores 23
surrounding the drive shaft 17, and each cylinder bore 23 slidably
accommodates each associated piston 24. Each piston 24 is coupled
to the periphery of the swash plate 19 through a pair of shoes 25.
As the swash plate 19 integrally rotates with the drive shaft 17,
each piston 24 reciprocates in the axial direction of the drive
shaft 17 in the associated cylinder bore 23 through shoes 25.
[0021] As mentioned above, the front housing 1 and the rear housing
26 are secured by a plurality of bolts 4 via the annular rigid
plate 28. Thereby, force tightening each bolt 4 is dispersed, and
is equally acted on the rear end surface of the rear housing 26.
Therefore, deformation of an inner wall of the rear end of the rear
housing 26, that is, deformation of a thrust surface, is
suppressed, thus inhibiting an eccentric load from acting on a
thrust bearing 22.
[0022] In the compressor shown in FIG. 1, seven cylinder bores 23
are defined in a cylinder block 15 in equiangular positions, and
the front housing 1 and the rear housing 26 are connected by seven
bolts 4 as shown in FIG. 2. However, the number of the bolts 4 is
not limited. As the number of bolts 4 increases, the force
tightening the bolts 4 is effectively dispersed. Therefore,
deformation of the thrust surface is effectively inhibited.
[0023] All the bolts 4 do not need to be positioned on one rigid
plate 28. According to the second embodiment, the rigid plate 28
may be divided into some pieces as shown in FIG. 3, and each rigid
plate 28 supports the associated heads of the bolts 4.
[0024] Also, the rigid plate 28 used in the above embodiment is
annular in shape, however, the shape of the rigid plate 28 is not
limited. According to the third embodiment, if an end surface of a
housing disposing the rigid plate is flat, the rigid plate may be
disk-shaped, and a plurality of bolts may be positioned in
equiangular positions on an identical circumference, as shown in
FIG. 4.
[0025] In addition, since the rigid plate 28 is disposed on the
rear end surface of the rear housing 26 in the above embodiment,
the thrust bearing 22 is disposed on the inner wall of the rear end
of the rear housing 26. However, the rigid plate should be disposed
on an end surface of a front housing if a compressor has a thrust
bearing disposed on an inner wall of a front end of the front
housing 1.
[0026] As described above, the rigid plate is disposed between one
of the front and rear housings and heads of the bolts. The front
housing and the rear housing are connected by the bolts via the
rigid plate. Thereby, force tightening each bolt equally acts on
the end surface of one of the front and rear housings, with a
consequence of suppressed deformation of the thrust surface of the
housing. Accordingly, a noise during the operation of the
compressor and shortened durability of the thrust bearing due to
the deformation of the thrust bearing may be inhibited. In other
words, the force tightening the bolts may be increased without any
trouble so that the present invention is effective especially when
carbon dioxide is used as refrigerant gas.
[0027] The present examples and embodiments are to be considered as
illustrative and not restrictive and the invention is not to be
limited to the details given herein but may be modified within the
scope of the appended claims.
* * * * *