U.S. patent application number 14/780000 was filed with the patent office on 2016-02-04 for variable displacement swash plate type 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 Kazunari HONDA, Kei NISHII, Masaki OTA, Takahiro SUZUKI, Shinya YAMAMOTO, Hideharu YAMASHITA, Yusuke YAMAZAKI.
Application Number | 20160032910 14/780000 |
Document ID | / |
Family ID | 51623779 |
Filed Date | 2016-02-04 |
United States Patent
Application |
20160032910 |
Kind Code |
A1 |
YAMAMOTO; Shinya ; et
al. |
February 4, 2016 |
VARIABLE DISPLACEMENT SWASH PLATE TYPE COMPRESSOR
Abstract
Provided is a compressor, in which discharge capacity is changed
by an actuator, exhibiting high controllability while realizing
reduction in size. In the compressor, a movable body includes a
rear wall, a circumferential wall, and a coupling mechanism. The
coupling mechanism includes a first arm provided with a first
pulling point and a second arm provided with a second pulling
point. In the compressor, when the inclination angle of a swash
plate is increased, the movable body pulls the swash plate via the
first and second arms. At this time, in the compressor, pulling
force can be applied at two points, i.e., at the first pulling
point and the second pulling point. Consequently, in the
compressor, even when the size of the rear wall and the
circumferential wall is increased, the rigidity of the first and
second arms can be made lower.
Inventors: |
YAMAMOTO; Shinya;
(Kariya-shi, JP) ; OTA; Masaki; (Kariya-shi,
JP) ; SUZUKI; Takahiro; (Kariya-shi, JP) ;
HONDA; Kazunari; (Kariya-shi, JP) ; YAMASHITA;
Hideharu; (Kariya-shi, JP) ; NISHII; Kei;
(Kariya-shi, JP) ; YAMAZAKI; Yusuke; (Kariya-shi,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KABUSHIKI KAISHA TOYOTA JIDOSHOKKI |
Aichi |
|
JP |
|
|
Assignee: |
KABUSHIKI KAISHA TOYOTA
JIDOSHOKKI
Aichi
JP
|
Family ID: |
51623779 |
Appl. No.: |
14/780000 |
Filed: |
March 18, 2014 |
PCT Filed: |
March 18, 2014 |
PCT NO: |
PCT/JP2014/057236 |
371 Date: |
September 25, 2015 |
Current U.S.
Class: |
417/218 |
Current CPC
Class: |
F04B 27/1027 20130101;
F04B 1/295 20130101; F04B 27/1045 20130101; F04B 27/1804 20130101;
F04B 27/1081 20130101; F04B 27/18 20130101; F04B 27/1054 20130101;
F04B 2027/1813 20130101 |
International
Class: |
F04B 27/18 20060101
F04B027/18; F04B 27/08 20060101 F04B027/08; F04B 27/10 20060101
F04B027/10 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 27, 2013 |
JP |
2013-067086 |
Feb 26, 2014 |
JP |
2014-034820 |
Claims
1. A variable displacement swash plate type compressor comprising:
a housing in which a suction chamber, a discharge chamber, a swash
plate chamber, and at least one cylinder bore are formed; a drive
shaft extending along a drive axis and rotatably supported in the
housing; a swash plate rotatable in the swash plate chamber along
with rotation of the drive shaft; a link mechanism that is provided
between the drive shaft and the swash plate and permits change of
an inclination angle of the swash plate in a direction
perpendicular to the drive axis of the drive shaft; a piston
reciprocally accommodated in the cylinder bore; a conversion
mechanism that reciprocates the piston in the cylinder bore along
with rotation of the swash plate at a stroke corresponding to the
inclination angle; an actuator that is disposed in the swash plate
chamber and capable of changing the inclination angle; and a
control mechanism that controls the actuator, wherein the suction
chamber and the swash plate chamber communicate with each other,
the actuator includes a partition body provided on the drive shaft,
a movable body that is coupled to the swash plate via a coupling
mechanism and movable with respect to the partition body along the
drive axis of the drive shaft, and a control pressure chamber that
is defined by the partition body and the movable body and moves the
movable body by introducing a refrigerant from the discharge
chamber, the movable body is disposed so as to increase the
inclination angle by pulling the swash plate when pressure in the
control pressure chamber increases, the link mechanism includes a
coupling portion that is coupled to the swash plate, and the
coupling mechanism is disposed on an opposite side of the coupling
portion with respect to the drive shaft and includes a first arm
and a second arm provided at the movable body across the drive
axis.
2. The variable displacement swash plate type compressor according
to claim 1, wherein the at least one cylinder bore comprises at
least a first cylinder bore, a second cylinder bore, and a third
cylinder bore, the first cylinder bore, the second cylinder bore,
and the third cylinder bore are arranged concentrically at equal
angular intervals around the drive axis in the housing, a first
imaginary region and a second imaginary region are set in the swash
plate chamber, the first imaginary region being defined by a first
tangential line drawn from the drive axis to the first cylinder
bore at a side of the second cylinder bore and a second tangential
line drawn from the drive axis to the second cylinder bore at a
side of the first cylinder bore, the second imaginary region being
defined by a third tangential line drawn from the drive axis to the
second cylinder bore at a side of the third cylinder bore and a
fourth tangential line drawn from the drive axis to the third
cylinder bore at a side of the second cylinder bore, and the first
arm is located within the first imaginary region and the second arm
is located within the second imaginary region.
3. The variable displacement swash plate type compressor according
to claim 1, wherein the swash plate is provided with a pulled
portion that protrudes between the first arm and the second arm,
and a driving force is transmitted between the first arm, the
second arm, and the pulled portion.
4. The variable displacement swash plate type compressor according
to claim 3, wherein a pin extending in a direction perpendicular to
the drive axis is inserted through the first arm, the pulled
portion, and the second arm.
Description
TECHNICAL FIELD
[0001] The present invention relates to a variable displacement
swash plate type compressor.
BACKGROUND ART
[0002] A conventional variable displacement swash plate type
compressor (hereinafter referred to as a compressor) is disclosed
in Patent Literature 1. This compressor includes a housing which is
formed by a front housing, a cylinder block, and a rear housing. A
suction chamber and a discharge chamber are formed in each of the
front housing and the rear housing. A swash plate chamber and
plural cylinder bores are formed in the cylinder block. A drive
shaft is rotatably supported in the housing. The swash plate
chamber accommodates a swash plate, which is rotatable along with
rotation of the drive shaft. A link mechanism is provided between
the drive shaft and the swash plate. The link mechanism permits
change of the inclination angle of the swash plate. The inclination
angle is defined as an angle of the swash plate with respect to a
direction perpendicular to the drive axis of the drive shaft. A
piston is reciprocally accommodated in each of the cylinder bores.
A pair of shoes provided for each piston serves as a conversion
mechanism and reciprocates the piston in each of the cylinder bores
along with rotation of the swash plate at a stroke corresponding to
the inclination angle. An actuator includes a movable body and a
control pressure chamber. The actuator is capable of changing the
inclination angle by changing the volume of the control pressure
chamber. The actuator is controlled by a control mechanism.
[0003] The swash plate has a pair of first arms extending toward
the front housing and a pair of second arms extending toward the
rear housing. Furthermore, a lug arm is fixed to the drive shaft.
The first arms are coupled to the lug arm via a first pin. The
second arms are coupled to the movable body via a second pin. The
first and second arms, the lug arm, the movable body, and the first
and second pins constitute the link mechanism.
[0004] In this compressor, the control mechanism raises the
pressure in the control pressure chamber by using the pressure of
refrigerant in the discharge chamber and thereby increases the
inclination angle of the swash plate via the link mechanism. At
this time, the movable body pushes the swash plate via the second
arms. The swash plate pushed by the movable body pushes the lug arm
via the first arms. As a result, the length of the link mechanism
in an axial direction of the drive shaft is reduced, and thereby,
the inclination angle of the swash plate is increased. In this way,
discharge capacity per rotation of the drive shaft is increased in
this compressor.
CITATION LIST
Patent Literature
[0005] Patent Literature 1: Japanese Patent Laid-Open No.
5-172052
SUMMARY OF INVENTION
Technical Problem
[0006] In a compressor in which the discharge capacity is changed
by an actuator as described above, higher controllability may be
required.
[0007] To deal with this, in the conventional compressor described
above, it is conceivable to upsize the movable body in a radial
direction in order to reliably increase the discharge capacity
using the pressure rise in the control pressure chamber. In this
case, however, in order to prevent interference between the movable
body and the swash plate when its inclination angle is large, the
swash plate chamber has to be upsized, and therefore the compressor
has to be upsized.
[0008] Furthermore, in this compressor, since the inclination angle
is increased by having the movable body push the swash plate, the
movable body needs to push the swash plate with a large pushing
force against a compressive reaction force and a suction reaction
force which gradually increase. Consequently, in the compressor,
when the inclination angle is increased, a large pushing force acts
on the second arms. If it is attempted to provide the second arms
with high rigidity enough to withstand the load of such a pushing
force, the size of the second arms will need to be increased. The
same applies to the first arms. If the size of the movable body is
increased in the radial direction as described above, the first and
second arms will need to have higher rigidity because the pushing
force acting on the first and second arms will become greater. Such
upsizing of the first and second arms will also lead to the
upsizing of the swash plate chamber.
[0009] The present invention has been made in view of the
conventional circumstances described above, and an object of the
invention is to provide a compressor, in which discharge capacity
is changed by an actuator, exhibiting high controllability while
realizing reduction in size.
Solution to Problem
[0010] A variable displacement swash plate type compressor
according to the present invention comprises: a housing in which a
suction chamber, a discharge chamber, a swash plate chamber, and at
least one cylinder bore are formed; a drive shaft extending along a
drive axis and rotatably supported in the housing; a swash plate
rotatable in the swash plate chamber along with rotation of the
drive shaft; a link mechanism that is provided between the drive
shaft and the swash plate and permits change of an inclination
angle of the swash plate in a direction perpendicular to the drive
axis of the drive shaft; a piston reciprocally accommodated in the
cylinder bore; a conversion mechanism that reciprocates the piston
in the cylinder bore along with rotation of the swash plate at a
stroke corresponding to the inclination angle; an actuator that is
disposed in the swash plate chamber and capable of changing the
inclination angle; and a control mechanism that controls the
actuator,
[0011] wherein the suction chamber and the swash plate chamber
communicate with each other,
[0012] the actuator includes a partition body provided on the drive
shaft, a movable body that is coupled to the swash plate via a
coupling mechanism and movable with respect to the partition body
along the drive axis of the drive shaft, and a control pressure
chamber that is defined by the partition body and the movable body
and moves the movable body by introducing a refrigerant from the
discharge chamber,
[0013] the movable body is disposed so as to increase the
inclination angle by pulling the swash plate when pressure in the
control pressure chamber increases,
[0014] the link mechanism includes a coupling portion that is
coupled to the swash plate, and
[0015] the coupling mechanism is disposed on an opposite side of
the coupling portion with respect to the drive shaft and includes a
first arm and a second arm provided at the movable body across the
drive axis.
[0016] In the compressor according to the present invention, when
the inclination angle of the swash plate is increased, the movable
body pulls the swash plate. In other words, in this compressor,
when the swash plate is displaced in a direction of increasing the
inclination angle, the movable body moves away from the swash
plate. Consequently, in the compressor, even if the size of the
movable body is increased in order to reliably increase the
discharge capacity due to the pressure rise in the control pressure
chamber, the movable body does not interfere with the swash plate.
Therefore, it is possible in this compressor to prevent upsizing of
the swash plate chamber.
[0017] In this compressor, the movable body is coupled to the swash
plate via the coupling mechanism. The movable body applies a
pulling force to the swash plate via the coupling mechanism in
order to increase the inclination angle of the swash plate. In the
case where the inclination angle is increased by pulling the swash
plate, less compressive reaction force and less suction reaction
force are exerted as compared with the case where the inclination
angle is increased by pushing the swash plate. Therefore, in this
compressor, a large pulling force is not required to increase the
inclination angle of the swash plate.
[0018] Furthermore, in this compressor, the coupling mechanism
includes the first arm and the second arm. The first arm and the
second arm are provided on the movable body across the drive axis.
The pulling force can be applied by the first arm and the second
arm. Therefore, in this compressor, the pulling force that each of
the first arm and the second arm exerts on the swash plate can be
made less as compared with the case where, for example, the
coupling mechanism has only a single arm. In the compressor,
although the movable body pushes the swash plate via the first and
second arms when the inclination angle of the swash plate is
decreased, the pushing force at that time is not so large. This is
because a centrifugal force acts on a rotating body, which includes
the swash plate and the movable body, in a direction of decreasing
the inclination angle.
[0019] For these reasons, as described above, even when the size of
the movable body is increased in this compressor, the rigidity of
the first arm and the second arm required thereby can be made
lower. Therefore, it is possible in this compressor to prevent
upsizing of the coupling mechanism.
[0020] Thus, the compressor according to the present invention, in
which the discharge capacity is changed by an actuator, exhibits
high controllability while realizing reduction in size.
[0021] In the compressor according to the present invention, the at
least one cylinder bore comprises at least a first cylinder bore, a
second cylinder bore, and a third cylinder bore. The first cylinder
bore, the second cylinder bore, and the third cylinder bore may be
arranged concentrically at equal angular intervals around the drive
axis in the housing. A first imaginary region and a second
imaginary region may be set in the swash plate chamber. The first
imaginary region is defined by a first tangential line drawn from
the drive axis to the first cylinder bore at a side of the second
cylinder bore and a second tangential line drawn from the drive
axis to the second cylinder bore at a side of the first cylinder
bore. The second imaginary region is defined by a third tangential
line drawn from the drive axis to the second cylinder bore at a
side of the third cylinder bore and a fourth tangential line drawn
from the drive axis to the third cylinder bore at a side of the
second cylinder bore. It is preferable that the first arm is
located within the first imaginary region and the second arm is
located within the second imaginary region.
[0022] In this case, the first arm and the second arm do not
obstruct the pistons reciprocating in the first to third cylinder
bores. Therefore, it is possible to surely reduce the size of the
compressor.
[0023] The swash plate may be provided with a pulled portion that
protrudes between the first arm and the second arm. It is
preferable that a driving force is transmitted between the first
arm, the second arm, and the pulled portion. In this case, the
movable body stably rotates together with the drive shaft, and the
swash plate also stably rotates together with the movable body and
thus together with the drive shaft.
[0024] In the compressor according to the present invention, the
first arm and the second arm may be separately coupled to the
pulled portion by using different pins or the like.
[0025] In particular, it is preferable that a pin extending in a
direction perpendicular to the drive axis is inserted through the
first arm, the pulled portion, and the second arm. In this case,
the first arm, the pulled portion, and the second arm can be
coupled together easily. In this case, it is further possible to
reduce the number of components and facilitate manufacturing as
compared with the case of using different pins to couple the first
arm and the pulled portion and couple the second arm and the pulled
portion respectively as described above. Furthermore, in this case,
the pin is less likely to come off the first arm, the second arm,
and the pulled portion, and thus reliability is improved.
Advantageous Effects of Invention
[0026] The compressor according to the present invention, in which
the discharge capacity can be changed by the actuator, exhibits
high controllability while realizing reduction in size.
BRIEF DESCRIPTION OF DRAWINGS
[0027] FIG. 1 is a sectional view of a compressor according to an
embodiment at the time of maximum displacement.
[0028] FIG. 2 is a schematic diagram showing a control mechanism of
the compressor according to the embodiment.
[0029] FIG. 3 is a sectional view of the compressor according to
the embodiment when taken along the line and viewed in the
direction of arrow III in FIG. 1.
[0030] FIG. 4A is a front view showing a swash plate of the
compressor according to the embodiment.
[0031] FIG. 4B is a sectional view showing the swash plate of the
compressor according to the embodiment.
[0032] FIG. 5 is a sectional view of the compressor according to
the embodiment at the time of minimum displacement.
[0033] FIG. 6 is a perspective view showing a movable body of the
compressor according to the embodiment when viewed from the
front.
[0034] FIG. 7 is a schematic top view showing the movable body of
the compressor according to the embodiment.
DESCRIPTION OF EMBODIMENTS
[0035] An embodiment, which embodies the present invention, will be
described below with reference to the drawings. The compressor
according to the embodiment is a variable displacement double head
swash plate type compressor. This compressor is mounted on a
vehicle and constitutes a refrigeration circuit of vehicle
air-conditioning apparatus.
[0036] As shown in FIG. 1, a compressor according to the embodiment
comprises a housing 1, a drive shaft 3, a swash plate 5, a link
mechanism 7, plural pistons 9, a pair of shoes 11a and 11b, and an
actuator 13 as well as a control mechanism 15 which is shown in
FIG. 2.
[0037] As shown in FIG. 1, the housing 1 includes a rear housing 17
located at a rear position in the compressor, a front housing 19
located at a front position in the compressor, first and second
cylinder blocks 21 and 23 located between the front housing 19 and
the rear housing 17, and first and second valve forming plates 39
and 41.
[0038] The aforementioned control mechanism 15 is provided in the
rear housing 17. Also, a first suction chamber 27a, a first
discharge chamber 29a, and a pressure regulation chamber 31 are
formed in the rear housing 17. The pressure regulation chamber 31
is located in central part of the rear housing 17. The first
suction chamber 27a is formed into an annular shape and located on
an outer peripheral side of the pressure regulation chamber 31 in
the rear housing 17. The first discharge chamber 29a is also formed
into an annular shape and located on an outer peripheral side of
the first suction chamber 27a in the rear housing 17.
[0039] A first rear-side communication passage 18a is formed in the
rear housing 17. The rear end of the first rear-side communication
passage 18a communicates with the first discharge chamber 29a, and
the front end thereof opens at the front end of the rear housing
17.
[0040] A boss 19a, which protrudes frontward, is formed in the
front housing 19. A shaft seal device 25 is provided in the boss
19a. A second suction chamber 27b and a second discharge chamber
29b are formed in the front housing 19. The second suction chamber
27b is located on an inner peripheral side in the front housing 19.
The second discharge chamber 29b is formed into an annular shape
and located on an outer peripheral side of the second suction
chamber 27b in the front housing 19.
[0041] A first front-side communication passage 20a is formed in
the front housing 19. The front end of the first front-side
communication passage 20a communicates with the second discharge
chamber 29b, and the rear end thereof opens at the rear end of the
front housing 19.
[0042] A swash plate chamber 33 is formed between the first
cylinder block 21 and the second cylinder block 23. The swash plate
chamber 33 is located at an approximate center in the front-rear
direction of the housing 1.
[0043] As shown in FIG. 3, first to fifth rear-side cylinder bores
21a to 21e are formed in the first cylinder block 21 so as to be
parallel to one another at equal angular intervals in a
circumferential direction. Also, as shown in FIG. 1, a first shaft
hole 211 is formed in the first cylinder block 21 to allow the
drive shaft 3 to be inserted therethrough. The rear end of the
first shaft hole 211 communicates with the pressure regulation
chamber 31. A first sliding bearing 22a is provided in the first
shaft hole 211. A roller bearing may be provided instead of the
first sliding bearing 22a.
[0044] The first cylinder block 21 has a first recess 212, which
communicates with the first shaft hole 211 and is coaxial with the
first shaft hole 211. The first recess 212 also communicates with
the swash plate chamber 33 and forms part of the swash plate
chamber 33. The first recess 212 is shaped such that its diameter
becomes smaller toward the rear end in a stepwise manner. A first
thrust bearing 35a is provided on the rear end of the first recess
212. As shown in FIG. 3, five connecting passages 37a are formed in
the first cylinder block 21 to allow the swash plate chamber 33 to
communicate with the first suction chamber 27a. The connecting
passages 37a are formed at equal angular intervals in the
circumferential direction so as to be located between the
respective first to fifth rear-side cylinder bores 21a to 21e.
Also, as shown in FIG. 1, a first retainer groove 213 is provided
in the first cylinder block 21 to restrict a maximum opening degree
of first suction reed valves 391a described later.
[0045] The first cylinder block 21 includes an outlet port 160, a
confluence discharge chamber 161, a third front-side communication
passage 20c, a second rear-side communication passage 18b, and an
inlet port 330. The front end of the second rear-side communication
passage 18b communicates with the confluence discharge chamber 161
and the rear end thereof opens at the rear end of the first
cylinder block 21. The outlet port 160 and the confluence discharge
chamber 161 communicate with each other. Via the outlet port 160,
the confluence discharge chamber 161 is connected to a condenser
(not shown) constituting a refrigeration circuit. The front end of
the third front-side communication passage 20c opens at the front
end of the first cylinder block 21, and the rear end thereof
communicates with the confluence discharge chamber 161. The inlet
port 330 communicates with the swash plate chamber 33. This inlet
port 330 is connected to an evaporator (not shown) constituting the
refrigeration circuit.
[0046] The second cylinder block 23 has a first front-side cylinder
bore 23a which corresponds to the first rear-side cylinder bore
21a. Thereby, the first rear-side cylinder bore 21a is paired with
the first front-side cylinder bore 23a in the front-rear direction.
The first rear-side cylinder bore 21a and the first front-side
cylinder bore 23a are equal in diameter. Similarly, the second
cylinder block 23 has second to fifth front-side cylinder bores
(not shown) which correspond respectively to the second to fifth
rear-side cylinder bores 21b to 21e.
[0047] A second shaft hole 23b is formed in the second cylinder
block 23 to allow the drive shaft 3 to be inserted therethrough. A
second sliding bearing 22b is provided in the second shaft hole
23b. A roller bearing may be provided instead of the second sliding
bearing 22b.
[0048] The second cylinder block 23 has a second recess 23c, which
communicates with the second shaft hole 23b and is coaxial with the
second shaft hole 23b. The second recess 23c also communicates with
the swash plate chamber 33 and forms part of the swash plate
chamber 33. Thereby, the rear end of the second shaft hole 23b
communicates with the swash plate chamber 33. The second recess 23c
is shaped such that its diameter becomes smaller toward the front
end in a stepwise manner. A second thrust bearing 35b is provided
on the front end of the second recess 23c. Plural connecting
passages 37b are formed in the second cylinder block 23 to allow
the swash plate chamber 33 to communicate with the second suction
chamber 27b. Also, a second retainer groove 23e is provided in the
second cylinder block 23 to restrict a maximum opening degree of
respective suction reed valves 411a described later.
[0049] A second front-side communication passage 20b is formed in
the second cylinder block 23. The front end of the second
front-side communication passage 20b opens at the front end of the
second cylinder block 23, and the rear end thereof opens at the
rear end the second cylinder block 23. The second front-side
communication passage 20b communicates with the front end of the
third front-side communication passage 20c when the first cylinder
block 21 and the second cylinder block 23 are joined together.
[0050] The first valve forming plate 39 is provided between the
rear housing 17 and the first cylinder block 21. Also, the second
valve forming plate 41 is provided between the front housing 19 and
the second cylinder block 23.
[0051] The first valve forming plate 39 includes a first valve
plate 390, a first suction valve plate 391, a first discharge valve
plate 392, and a first retainer plate 393. Plural first suction
ports 390a, which correspond respectively to the first to fifth
rear-side cylinder bores 21a to 21e, are formed in the first valve
plate 390, the first discharge valve plate 392, and the first
retainer plate 393. Plural first discharge ports 390b, which
correspond respectively to the first to fifth rear-side cylinder
bores 21a to 21e, are formed in the first valve plate 390 and the
first suction valve plate 391. A first suction communication hole
390c is formed in the first valve plate 390, the first suction
valve plate 391, the first discharge valve plate 392, and the first
retainer plate 393. A first discharge communication hole 390d is
formed in the first valve plate 390 and the first suction valve
plate 391.
[0052] The first to fifth rear-side cylinder bores 21a to 21e
communicate with the first suction chamber 27a through the
respective first suction ports 390a. Also, the first to fifth
rear-side cylinder bores 21a to 21e communicate with the first
discharge chamber 29a through the respective first discharge ports
390b. The first suction chamber 27a communicates with the
connecting passages 37a through the first suction communication
hole 390c. The first rear-side communication passage 18a
communicates with the second rear-side communication passage 18b
through the first discharge communication hole 390d.
[0053] The first suction valve plate 391 is provided on the front
face of the first valve plate 390. The first suction valve plate
391 has the first suction reed valves 391a, the number of which is
equal to the number of the first suction ports 390a, capable of
opening and closing the respective first suction ports 390a by
elastic deformation. The first discharge valve plate 392 is
provided on the rear face of the first valve plate 390. The first
discharge valve plate 392 has first discharge reed valves 392a, the
number of which is equal to the number of the first discharge ports
390b, capable of opening and closing the respective first discharge
ports 390b by elastic deformation. The first retainer plate 393 is
provided on the rear face of the first discharge valve plate 392.
The first retainer plate 393 restricts a maximum opening degree of
the respective first discharge reed valves 392a.
[0054] The second valve forming plate 41 includes a second valve
plate 410, a second suction valve plate 411, a second discharge
valve plate 412, and a second retainer plate 413. Second suction
ports 410a, the number of which is equal to the number of the first
to fifth front-side cylinder bores 23a, are formed in the second
valve plate 410, the second discharge valve plate 412, and the
second retainer plate 413. Second discharge ports 410b, the number
of which is equal to the number of the first to fifth front-side
cylinder bores 23a, are formed in the second valve plate 410 and
the second suction valve plate 411. A second suction communication
hole 410c is formed in the second valve plate 410, the second
suction valve plate 411, the second discharge valve plate 412, and
the second retainer plate 413. A second discharge communication
hole 410d is formed in the second valve plate 410 and the second
suction valve plate 411.
[0055] The first to fifth front-side cylinder bores 23a communicate
with the second suction chamber 27b through the respective second
suction ports 410a. Also, the first to fifth front-side cylinder
bores 23a communicate with the second discharge chamber 29b through
the respective second discharge ports 410b. The second suction
chamber 27b communicates with the connecting passages 37b through
the second suction communication hole 410c. The first front-side
communication passage 20a communicates with the second front-side
communication passage 20b through the second discharge
communication hole 410d.
[0056] The second suction valve plate 411 is provided on the rear
face of the second valve plate 410. The second suction valve plate
411 has the second suction reed valves 411a, the number of which is
equal to the number of the second suction ports 410a, capable of
opening and closing the respective second suction ports 410a by
elastic deformation. Also, the second discharge valve plate 412 is
provided on the front face of the second valve plate 410. The
second discharge valve plate 412 has second discharge reed valves
412a, the number of which is equal to the number of the second
discharge ports 410b, capable of opening and closing the respective
second discharge ports 410b by elastic deformation. The second
retainer plate 413 is provided on the front face of the second
discharge valve plate 412. The second retainer plate 413 restricts
a maximum opening degree of the respective second discharge reed
valves 412a.
[0057] In the compressor, a first discharge communication passage
18 is formed by the first rear-side communication passage 18a, the
first discharge communication hole 390d, and the second rear-side
communication passage 18b. Also, a second discharge communication
passage 20 is formed by the first front-side communication passage
20a, the second discharge communication hole 410d, the second
front-side communication passage 20b, and the third front-side
communication passage 20c.
[0058] Also, in the compressor, the first and second suction
chambers 27a and 27b and the swash plate chamber 33 communicate
with each other via the connecting passages 37a and 37b and the
first and second suction communication holes 390c and 410c.
Accordingly, the pressure in the first and second suction chambers
27a and 27b and the swash plate chamber 33 are substantially equal.
Because a low-pressure refrigerant gas which has passed through an
evaporator flows into the swash plate chamber 33 through the inlet
port 330, the pressure in the swash plate chamber 33 and the first
and second suction chambers 27a and 27b is lower than the pressure
in the first and second discharge chambers 29a and 29b.
[0059] The drive shaft 3 is made up of a drive shaft body 30
extending along a drive axis O, a first support member 43a, and a
second support member 43b. A first small-diameter portion 30a is
formed on the rear end side of the drive shaft body 30, and a
second small-diameter portion 30b is formed on the front end side
of the drive shaft body 30. The drive shaft body 30 extends
rearward from the front side of the housing 1 by being inserted
rearward from the boss 19a through the first and second sliding
bearings 22a and 22b. Consequently, the drive shaft body 30 and
thus the drive shaft 3 are supported by the housing 1 so as to be
rotatable around the drive axis O. The front end of the drive shaft
body 30 is located in the boss 19a and the rear end thereof
protrudes into the pressure regulation chamber 31.
[0060] The swash plate 5, the link mechanism 7, and the actuator 13
are provided on the drive shaft body 30. The swash plate 5, the
link mechanism 7, and the actuator 13 are all disposed in the swash
plate chamber 33.
[0061] The first support member 43a is press-fitted to the rear end
of the first small-diameter portion 30a of the drive shaft body 30
and located in the first shaft hole 211. A flange 430 is formed on
the front end of the first support member 43a. The flange 430
protrudes into the first recess 212 and abuts the first thrust
bearing 35a. The rear end of the first support member 43a protrudes
into the pressure regulation chamber 31. In the first support
member 43a, a first slide member 431 and a second slide member 432
made of resin are provided in the rear of the flange 430. The first
and second slide members 431 and 432 are in contact with and
slidable along an inner circumferential surface of the first shaft
hole 211.
[0062] The second support member 43b is press-fitted to the second
small-diameter portion 30b of the drive shaft body 30 and located
inside of the second sliding bearing 22b in the second shaft hole
23b. Also, the second support member 43b includes a flange 433
configured to abut the second thrust bearing 35b and a mounting
portion (not shown) configured to allow a second pin 47b, which
will be described later, to be inserted therethrough. A front end
of a first return spring 44a is fixed to the second support member
43b. The first return spring 44a extends from the second support
member 43b toward the swash plate chamber 33 along the drive axis
O.
[0063] The swash plate 5 has a flat annular shape and includes a
front face 5a and a rear face 5b. The front face 5a faces frontward
of the compressor in the swash plate chamber 33. Also, the rear
face 5b faces rearward of the compressor in the swash plate chamber
33.
[0064] The swash plate 5 includes a ring plate 45. As shown in FIG.
4, the ring plate 45 has a flat annular shape with an insertion
hole 45a formed in the center. The swash plate 5 is attached to the
drive shaft 3 by inserting the drive shaft body 30 through the
insertion hole 45a in the swash plate chamber 33 (see FIG. 1).
[0065] Also, as shown in FIG. 4A, a groove 45b is formed on one end
side of the ring plate 45 and a pulled portion 45c is formed on the
opposite end side of the ring plate 45. As shown in FIG. 4B, the
groove 45b extends through the swash plate 5 from the front face 5a
to the rear face 5b. The pulled portion 45c protrudes from the rear
face 5b toward the rear of the swash plate 5 so as to be located
between first and second arms 132 and 133 described later. A pin
hole 450 is formed in the pulled portion 45c.
[0066] As shown in FIG. 1, the link mechanism 7 has a lug arm 49.
The lug arm 49 is placed frontward relative to the swash plate 5 in
the swash plate chamber 33 and located between the swash plate 5
and the second support member 43b. The lug arm 49 is formed so as
to be substantially L-shaped from the front end toward the rear
end. A weight 49a is formed at the rear end of the lug arm 49. The
weight 49a extends approximately half around a circumference of the
actuator 13. The shape of the weight 49a may be designed as
appropriate.
[0067] The rear end side of the lug arm 49 is connected to the one
end side of the ring plate 45 with a first pin 47a. The first pin
47a corresponds to the coupling portion according to the present
invention. When the axis of the first pin 47a is defined as a first
pivot axis M1, the rear end side of the lug arm 49 is supported
around the first pivot axis M1 so as to be pivotable with respect
to the one end side of the ring plate 45, i.e., the swash plate 5.
The first pivot axis M1 extends in a direction perpendicular to the
drive axis O of the drive shaft 3.
[0068] The front end of the lug arm 49 is connected to the second
support member 43b via the second pin 47b. When the axis of the
second pin 47b is defined as a second pivot axis M2, the front end
of the lug arm 49 is supported around the second pivot axis M2 so
as to be pivotable with respect to the second support member 43b,
i.e., the drive shaft 3. The second pivot axis M2 extends parallel
to the first pivot axis M1. The link mechanism 7 according to the
present invention is made up of the lug arm 49, the first and
second pins 47a and 47b, and in addition, the first and second arms
132 and 133 and a third pin 47c, which will be described later.
[0069] The weight 49a is provided so as to extend at the rear end
of the lug arm 49, i.e., extend on the opposite side of the second
pivot axis M2 with reference to the first pivot axis M1. As the lug
arm 49 is supported by the ring plate 45 with the first pin 47a,
the weight 49a passes through the groove 45b in the ring plate 45
and reaches the rear face side of the ring plate 45, i.e., the side
of the rear face 5b of the swash plate 5. Therefore, a centrifugal
force produced by rotation of the swash plate 5 around the drive
axis O also acts on the weight 49a at the side of the rear face 5b
of the swash plate 5.
[0070] In this compressor, the swash plate 5 is able to rotate
together with the drive shaft 3 as the swash plate 5 is connected
to the drive shaft 3 by the link mechanism 7. Also, the swash plate
5 is able to change its inclination angle due to the pivotal
movement of both ends of the lug arm 49 around the first pivot axis
M1 and the second pivot axis M2, respectively.
[0071] The pistons 9 each has a first head 9a at its rear end and a
second head 9b at its front end. The first head 9a is reciprocally
accommodated in each of the first to fifth rear-side cylinder bores
21a to 21e. The first head 9a and the first valve forming plate 39
define a first compression chamber 210 in each of the first to
fifth rear-side cylinder bores 21a to 21e. The second head 9b is
reciprocally accommodated in each of the first to fifth front-side
cylinder bores 23a. The second head 9b and the second valve forming
plate 41 define a second compression chamber 230 in each of the
first to fifth front-side cylinder bores 23a.
[0072] An engaging portion 9c is formed in the middle of each of
the pistons 9. Hemispherical shoes 11a and 11b are provided in each
of the engaging portions 9c. The shoes 11a and 11b convert rotation
of the swash plate 5 into reciprocating movement of the pistons 9.
The shoes 11a and 11b correspond to the conversion mechanism
according to the present invention. Thus, the respective first
heads 9a are able to reciprocate in the first to fifth rear-side
cylinder bores 21a to 21e and the respective second heads 9b are
able to reciprocate in the first to fifth front-side cylinder bores
23a at a stroke corresponding to the inclination angle of the swash
plate 5.
[0073] Here, in the compressor, when the stroke of the pistons 9
changes according to the change in the inclination angle of the
swash plate 5, respective top dead center positions of the first
heads 9a and the second heads 9b move. Specifically, as shown in
FIG. 5, as the inclination angle of the swash plate 5 decreases,
the top dead center positions of the first and second heads 9a and
9b move such that the volume of the first compression chamber 210
become larger than the volume of the second compression chamber
230.
[0074] The actuator 13 is placed in the swash plate chamber 33. The
actuator 13 is located rearward of the swash plate 5 in the swash
plate chamber 33 and able to advance into the first recess 212. The
actuator 13 includes a movable body 13a, a partition body 13b, and
a control pressure chamber 13c. The control pressure chamber 13c is
formed between the movable body 13a and the partition body 13b.
[0075] As shown in FIG. 6, the movable body 13a includes a rear
wall 130, a circumferential wall 131, and a coupling mechanism 14.
The rear wall 130 is located at a rear position in the movable body
13a and extends radially in a direction away from the drive axis O.
The rear wall 130 has an insertion hole 130a through which the
first small-diameter portion 30a of the drive shaft body 30 is
inserted. The circumferential wall 131 continues from an outer
circumferential edge of the rear wall 130 and extends frontward at
the movable body 13a. The movable body 13a is formed into a
bottomed cylindrical shape by the rear wall 130, the
circumferential wall 131, and the coupling mechanism 14.
[0076] The coupling mechanism 14 has the first arm 132 and the
second arm 133. The first arm 132 and the second arm 133 are formed
at the front end of the circumferential wall 131 and protrude
frontward of the movable body 13a. Specifically, the first arm 132
is formed at the left front end of the circumferential wall 131,
while the second arm 133 is formed at the right front end of the
circumferential wall 131. Since the first arm 132 and the second
arm 133 protrude frontward of the movable body 13a in this way, a
recessed portion 134 is formed between the first arm 132 and the
second arm 133 by the first and second arms 132 and 133 and the
front end face of the circumferential wall 131. A first pulling
point 132a is set on the first arm 132 and a second pulling point
133a is set on the second arm 133. The first and second pulling
points 132a and 133a also serve as pin holes through which the
third pin 47c is inserted.
[0077] As shown in FIG. 7, the first arm 132 and the second arm 133
are formed symmetrically and disposed across the drive axis O. More
specifically, the first arm 132 and the second arm 133 face each
other across an imaginary plane X which is defined by the drive
axis O, the top dead center position of the swash plate 5, and the
bottom dead center position of the swash plate 5. Accordingly, the
first pulling point 132a and the second pulling point 133a of the
movable body 13a are also disposed across the imaginary plane X.
For ease of explanation, the shape of the first and second arms 132
and 133 etc. is simplified in FIG. 7.
[0078] As shown in FIG. 1, the partition body 13b is formed in a
disk shape having a diameter that is substantially equal to the
inside diameter of the movable body 13a. A second return spring 44b
is provided between the partition body 13b and ring plate 45.
Specifically, the rear end of the second return spring 44b is fixed
to the partition body 13b and the front end of the second return
spring 44b is fixed to the opposite end side of the ring plate
45.
[0079] The first small-diameter portion 30a of the drive shaft body
30 is inserted through the movable body 13a and the partition body
13b. The movable body 13a is attached to the drive shaft body 30 so
as to be accommodated in the first recess 212 and faces the link
mechanism 7 across the swash plate 5. The partition body 13b is
placed in the movable body 13a at a position rearward of the swash
plate 5, and its periphery is surrounded by the circumferential
wall 131. Consequently, the control pressure chamber 13c is formed
between the movable body 13a and the partition body 13b. The
control pressure chamber 13c is partitioned from the swash plate
chamber 33 by the rear wall 130 and the circumferential wall 131 of
the movable body 13a and the partition body 13b.
[0080] In the compressor, due to the insertion of the first
small-diameter portion 30a, the movable body 13a is able to rotate
with the drive shaft 3 and move along the drive axis O of the drive
shaft 3 in the swash plate chamber 33. On the other hand, the
partition body 13b is fixed to the first small-diameter portion 30a
in the state that the first small-diameter portion 30a has been
inserted therethrough. The partition body 13b is thus only able to
rotate together with the drive shaft 3, and not able to move in the
same manner as the movable body 13a. As a result, the movable body
13a moves along the drive axis O relative to the partition body
13b. The partition body 13b may be provided on the drive shaft body
30 so as to be movable along the drive axis O.
[0081] As shown in FIG. 3, a first imaginary region S1 and a second
imaginary region S2 are set in the swash plate chamber 33. The
first imaginary region S1 is defined by a first tangential line L1
drawn from the drive axis O to the first rear-side cylinder bore
21a at a side of the second rear-side cylinder bore 21b and a
second tangential line L2 drawn from the drive axis O to the second
rear-side cylinder bore 21b at a side of the first rear-side
cylinder bore 21a. The second imaginary region S2 is defined by a
third tangential line L3 drawn from the drive axis O to the second
rear-side cylinder bore 21b at a side of the third rear-side
cylinder bore 21c and a fourth tangential line L4 drawn from the
drive axis O to the third rear-side cylinder bore 21c at a side of
the second rear-side cylinder bore 21b.
[0082] In the compressor, the first and second arms 132 and 133 are
formed such that when the movable body 13a is attached to the drive
shaft body 30, the first arm 132 is positioned in the first
imaginary region S1 and the second arm 133 is positioned in the
second imaginary region S2. For ease of explanation, the shape of
the first and second arms 132 and 133 is simplified in FIG. 3.
[0083] As shown in FIG. 1, the first and second arms 132 and 133
are connected with the swash plate 5 with the third pin 47c.
Specifically, the pulled portion 45c shown in FIG. 4 is fitted to
the recessed portion 134 of the movable body 13a, and in this
state, the first and second arms 132 and 133 are connected with the
pulled portion 45c by the third pin 47c alone. Consequently, the
coupling mechanism 14 is placed on the opposite side of the first
pin 47a across the drive shaft 3, i.e., the drive axis O.
[0084] The third pin 47c extends in a direction perpendicular to
the drive axis O from the first pulling point 132a to the second
pulling point 133a through the pin hole 450 of the pulled portion
45c. Thereby, as shown in FIG. 1, when the axis of the third pin
47c is defined as an action axis M3, the swash plate 5 is supported
by the movable body 13a so as to be pivotable around the action
axis M3. The action axis M3 extends parallel to the first and
second pivot axes M1 and M2. The movable body 13a is coupled to the
swash plate 5 in this way.
[0085] The first small-diameter portion 30a has an axial path 3a,
which extends frontward from the rear end along the drive axis O,
and a radial path 3b, which extends in a radial direction from the
front end of the axial path 3a and opens at an outer
circumferential surface of the drive shaft body 30. The rear end of
the axial path 3a opens to the pressure regulation chamber 31. The
radial path 3b opens to the control pressure chamber 13c. The
control pressure chamber 13c thus communicates with the pressure
regulation chamber 31 through the radial path 3b and the axial path
3a.
[0086] A threaded portion 3d is formed on a tip end of the drive
shaft body 30. Via the threaded portion 3d, the drive shaft 3 is
connected to a pulley or an electro-magnetic clutch (not
shown).
[0087] As shown in FIG. 2, the control mechanism 15 includes a
low-pressure passage 15a, a high-pressure passage 15b, a control
valve 15c, an orifice 15d, the axial path 3a, and the radial path
3b.
[0088] The low-pressure passage 15a is connected to the pressure
regulation chamber 31 and the first suction chamber 27a. The
control pressure chamber 13c, the pressure regulation chamber 31,
and the first suction chamber 27a communicate with one another
through the low-pressure passage 15a, the axial path 3a, and the
radial path 3b. The high-pressure passage 15b is connected to the
pressure regulation chamber 31 and the first discharge chamber 29a.
The control pressure chamber 13c, the pressure regulation chamber
31, and the first discharge chamber 29a communicate with one
another through the high-pressure passage 15b, the axial path 3a,
and the radial path 3b. The orifice 15d is provided in the
high-pressure passage 15b.
[0089] The control valve 15c is provided on the low-pressure
passage 15a. The control valve 15c is able to adjust an opening
degree of the low-pressure passage 15a based on the pressure in the
first suction chamber 27a.
[0090] In the compressor, the inlet port 330 shown in FIG. 1 is
connected with a pipe leading to the evaporator while the outlet
port 160 is connected with a pipe leading to the condenser. The
condenser is connected to the evaporator through a pipe and an
expansion valve. The compressor, the evaporator, the expansion
valve, the condenser, etc. constitute the refrigeration circuit of
vehicle air-conditioning apparatus. Illustration of the evaporator,
the expansion valve, the condenser, and the pipes is omitted.
[0091] In the compressor configured as described above, by rotation
of the drive shaft 3, the swash plate 5 rotates and the pistons 9
reciprocate in the first to fifth rear-side cylinder bores 21a to
21e and the first to fifth front-side cylinder bores 23a. Thereby,
the first and second compression chambers 210 and 230 change their
volumes according to the piston stroke. In the compressor, a
suction phase for sucking refrigerant gas into the first and second
compression chambers 210 and 230, a compression phase for
compressing the refrigerant gas in the first and second compression
chambers 210 and 230, and a discharge phase for discharging the
compressed refrigerant gas into the first and second discharge
chambers 29a and 29b take place repeatedly.
[0092] The refrigerant gas discharged into the first discharge
chamber 29a passes through the first discharge communication
passage 18 and reaches the confluence discharge chamber 161.
Similarly, the refrigerant gas discharged into the second discharge
chamber 29b passes through the second discharge communication
passage 20 and reaches the confluence discharge chamber 161. After
reaching the confluence discharge chamber 161, the refrigerant gas
is discharged to the condenser through the outlet port 160.
[0093] While the suction stroke and so forth take place, a piston
compression force to reduce the inclination angle of the swash
plate 5 is applied to a rotation body made up of the swash plate 5,
the ring plate 45, the lug arm 49, and the first pin 47a. When the
inclination angle of the swash plate 5 is changed, the stroke of
the pistons 9 increases or decreases, and thereby it is possible to
control the displacement.
[0094] Specifically, when the control valve 15c, which is shown in
FIG. 2, of the control mechanism 15 increases the opening degree of
the low-pressure passage 15a, the pressure in the pressure
regulation chamber 31, and thus the pressure in the control
pressure chamber 13c becomes substantially equal to the pressure in
the first suction chamber 27a. Therefore, due to the piston
compression force acting on the swash plate 5, the movable body 13a
of the actuator 13 moves frontward in the swash plate chamber 33 as
shown in FIG. 5.
[0095] Consequently, in the compressor, the movable body 13a pushes
the swash plate 5 at the opposite end side frontward in the swash
plate chamber 33 about the action axis M3 via the first and second
pulling points 132a and 133a of the first and second arms 132 and
133. Thus, in the compressor, the opposite end side of the ring
plate 45, i.e., the opposite end side of the swash plate 5, pivots
clockwise around the action axis M3 against a biasing force of the
second return spring 44b. Also, the rear side of the lug arm 49
pivots counterclockwise around the first pivot axis M1 and the
front end of the lug arm 49 pivots counterclockwise around the
second pivot axis M2. The lug arm 49 thus comes close to the flange
433 of the second support member 43b. In this way, the swash plate
5 pivots using the action axis M3 as a point of action and using
the first pivot axis M1 as a fulcrum. This reduces the inclination
angle of the swash plate 5 with respect to a direction
perpendicular to the drive axis O of the drive shaft 3 and
decreases the stroke of the piston 9. Therefore, the discharge
capacity of the compressor per rotation of the drive shaft 3
decreases. The inclination angle of the swash plate 5 shown in FIG.
5 is the minimum value in this compressor.
[0096] Here, in this compressor, the centrifugal force acting on
the weight 49a is also applied to the swash plate 5. Thus, the
swash plate 5 of this compressor is easily displaced in a direction
of decreasing the inclination angle.
[0097] When the inclination angle of the swash plate 5 decreases,
the ring plate 45 abuts the rear end of the first return spring
44a. The first return spring 44a thus deforms elastically and the
rear end of the first return spring 44a comes close to the second
support member 43b.
[0098] In this compressor, as the inclination angle of the swash
plate 5 becomes smaller and the stroke of the pistons 9 decreases,
the top dead center position of the first heads 9a moves away from
the first valve forming plate 39. Thus, in the compressor, when the
inclination angle of the swash plate 5 approaches 0 degrees,
compression work is performed slightly in the second compression
chamber 230, whereas compression work is not performed in the first
compression chamber 210.
[0099] When the control valve 15c shown in FIG. 2 reduces the
opening degree of the low-pressure passage 15a, the pressure in the
pressure regulation chamber 31 increases due to the pressure of the
refrigerant gas in the first discharge chamber 29a, and thereby the
pressure in the control pressure chamber 13c increases. Thus, the
movable body 13a of the actuator 13 moves rearward in the swash
plate chamber 33 as shown in FIG. 1 against the piston compression
force acting on the swash plate 5.
[0100] Consequently, in the compressor, the movable body 13a pulls
the opposite end side of the swash plate 5 rearward in the swash
plate chamber 33 about the action axis M3 via the first and second
pulling points 132a and 133a of the first and second arms 132 and
133. Thus, in the compressor, the opposite end side of the swash
plate 5 pivots counterclockwise around the action axis M3. Also,
the rear side of the lug arm 49 pivots clockwise around the first
pivot axis M1 and the front end of the lug arm 49 pivots clockwise
around the second pivot axis M2. The lug arm 49 thus moves away
from the flange 433 of the second support member 43b. In this way,
the swash plate 5 pivots in a direction opposite to the direction
in the above-described case of decreasing the inclination angle,
using the action axis M3 as a point of action and using the first
pivot axis M1 as a fulcrum. This increases the inclination angle of
the swash plate 5 with respect to the direction perpendicular to
the drive axis O of the drive shaft 3 and thus increases the stroke
of the pistons 9. Consequently, the discharge capacity of the
compressor per rotation of the drive shaft 3 increases. The
inclination angle of the swash plate 5 shown in FIG. 1 is the
maximum value in this compressor. When the inclination angle of the
swash plate 5 has reached the maximum value, the rear wall 130 of
the movable body 13a abuts the first flange 430.
[0101] In this way, in the compressor, to increase the inclination
angle of the swash plate 5, the movable body 13a pulls the swash
plate 5 via the first and second pulling points 132a and 133a of
the first and second arms 132 and 133. In other words, in this
compressor, when the swash plate 5 is displaced in the direction of
increasing the inclination angle, the movable body 13a moves away
from the swash plate 5. Consequently, in the compressor, even if
the rear wall 130 and the circumferential wall 131 are upsized in
order to reliably increase the discharge capacity using the
pressure rise in the control pressure chamber 13c, no interference
will occur between the circumferential wall 131 and the swash plate
5. Therefore, it is possible in this compressor to prevent upsizing
of the swash plate chamber 33 when the rear wall 130 and the
circumferential wall 131 of the movable body 13a are upsized.
[0102] Furthermore, in this compressor, the coupling mechanism 14
includes the first and second arms 132 and 133. The first arm 132
is provided with the first pulling point 132a for applying a
pulling force to the swash plate 5 and the second arm 133 is
provided with the second pulling point 133a for applying a pulling
force to the swash plate 5. In the case where the inclination angle
is increased by pulling the swash plate 5, less compressive
reaction force and less suction reaction force are exerted as
compared with the case where the inclination angle is increased by
the pushing swash plate 5. Therefore, in this compressor, a large
pulling force is not required to increase the inclination angle of
the swash plate 5.
[0103] Furthermore, in this compressor, the first arm 132 and the
second arm 133 are arranged across the imaginary plane X defined by
the drive axis O, top dead center position of the swash plate 5,
and the bottom dead center position of the swash plate 5. The first
pulling point 132a and the second pulling point 133a are set on the
first arm 132 and the second arm 133, respectively. The first arm
132 and the second arm 133 are able to apply the pulling force at
two points, i.e., the first pulling point 132a and the second
pulling point 133a. Consequently, in this compressor, the pulling
force that each of the first arm 132 and the second arm 133 exerts
on the swash plate 5 can be made less as compared with the case
where, for example, the coupling mechanism 14 has only a single
arm. In this compressor, although the movable body 13a pushes the
swash plate 5 via the first and second arms 132 and 133 when the
inclination angle of the swash plate 5 is decreased, the pushing
force at that time is not so large. This is because a centrifugal
force acts on a rotation body including the swash plate 5 and the
movable body 13a in the direction of decreasing the inclination
angle.
[0104] For these reasons, as described above, even when the size of
the rear wall 130 and the circumferential wall 131 is increased in
this compressor, the rigidity of the first and second arms 132 and
133 required thereby can be made lower. Therefore, it is possible
in this compressor to prevent upsizing of the first and second arms
132 and 133, i.e., upsizing of the coupling mechanism 14.
[0105] Furthermore, in this compressor, the first imaginary region
S1 and the second imaginary region S2 are set in the swash plate
chamber 33. When the movable body 13a is attached to the drive
shaft body 30, the first arm 132 is positioned in the first
imaginary region S1 and the second arm 133 is positioned in the
second imaginary region S2. Consequently, in the compressor, the
first arm 132 and the second arm 133 do not obstruct the pistons 9
reciprocating in the first to fifth rear-side cylinder bores 21a to
21e and the first to fifth front-side cylinder bores 23a.
Therefore, it is possible to dispose the first arm 132 and the
second arm 133 in the vicinity of the first to fifth rear-side
cylinder bores 21a to 21e and the first to fifth front-side
cylinder bores 23a, i.e., in the vicinity of the respective pistons
9.
[0106] Therefore, the compressor according to the embodiment, in
which the discharge capacity is changed by the actuator 13,
exhibits high controllability while realizing reduction in
size.
[0107] In particular, the swash plate 5 of this compressor is
provided with the pulled portion 45c that protrudes between the
first arm 132 and the second arm 133. The pulled portion 45c is
fitted to the recessed portion 134 of the movable body 13a, and in
this state, the first and second arms 132 and 133 are connected
with the swash plate 5. Thereby, in the compressor, when the
movable body 13a rotates together with the drive shaft 3, a driving
force is transmitted between the first and second arms 132 and 133
and the pulled portion 45c. Therefore, in the compressor, the
movable body 13a rotates stably together with the drive shaft 3 and
the swash plate 5 also rotates stably together with the movable
body 13a and thus together with the drive shaft 3.
[0108] In addition, the third pin 47c extending in a direction
perpendicular to the drive axis O is inserted through the first arm
132, the pulled portion 45c, and the second arm 133. Consequently,
the first arm 132, the pulled portion 45c, and the second arm 133
can be coupled together easily. It is also possible to reduce the
number of components and facilitate manufacturing as compared with
the case of, for example, using different pins to couple the first
arm 132 and the pulled portion 45c and couple the second arm 133
and the pulled portion 45c. Furthermore, in this compressor, the
third pin 47c is less likely to come off the first and second arms
132 and 133 and the pulled portion 45c, and thus reliability is
improved.
[0109] Although the present invention has been described above by
referring to the embodiment, needless to say, the present invention
is not limited to the above embodiment and may be modified and
applied as required without departing from the gist of the present
invention.
[0110] For example, the compressor may be configured as a variable
displacement single head swash plate type compressor by forming
cylinder bores only in either of the first cylinder block 21 and
the second cylinder block 23.
[0111] Also, the control mechanism 15 may be configured such that
the control valve 15c is provided on the high-pressure passage 15b
while the orifice 15d is provided in the low-pressure passage 15a.
In this case, it is possible to adjust the opening degree of the
high-pressure passage 15b using the control valve 15c. Thereby, the
pressure in the control pressure chamber 13c can be increased
quickly due to the pressure of refrigerant gas in the first
discharge chamber 29a, and the discharge capacity can be increased
quickly.
INDUSTRIAL APPLICABILITY
[0112] The present invention is applicable to air-conditioning
apparatus and the like.
REFERENCE SIGNS LIST
[0113] 1 Housing
[0114] 3 Drive shaft
[0115] 5 Swash plate
[0116] 7 Link mechanism
[0117] 9 Piston
[0118] 11a, 11b Shoe (conversion mechanism)
[0119] 13 Actuator
[0120] 13a Movable body
[0121] 13b Partition body
[0122] 13c Control pressure chamber
[0123] 14 Coupling mechanism
[0124] 15 Control mechanism
[0125] 21a First rear-side cylinder bore (first cylinder bore)
[0126] 21b Second rear-side cylinder bore (second cylinder
bore)
[0127] 21c Third rear-side cylinder bore (third cylinder bore)
[0128] 27a First suction chamber
[0129] 27b Second suction chamber
[0130] 29a First discharge chamber
[0131] 29b Second discharge chamber
[0132] 33 Swash plate chamber
[0133] 45c Pulled portion
[0134] 47a First pin (connecting portion)
[0135] 47c Third pin (pin)
[0136] 132 First arm
[0137] 133 Second arm
[0138] 210 First compression chamber
[0139] 230 Second compression chamber
[0140] L1 First tangential line
[0141] L2 Second tangential line
[0142] L3 Third tangential line
[0143] L4 Fourth tangential line
[0144] O Drive axis
[0145] S1 First imaginary region
[0146] S2 Second imaginary region
* * * * *