U.S. patent application number 15/040050 was filed with the patent office on 2016-08-18 for double-headed piston 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 Shohei FUJIWARA, Hiromichi OGAWA, Takahiro SUZUKI, Shinya YAMAMOTO.
Application Number | 20160238001 15/040050 |
Document ID | / |
Family ID | 56622041 |
Filed Date | 2016-08-18 |
United States Patent
Application |
20160238001 |
Kind Code |
A1 |
FUJIWARA; Shohei ; et
al. |
August 18, 2016 |
DOUBLE-HEADED PISTON TYPE COMPRESSOR
Abstract
In the compressor of the present invention, the first discharge
chamber is divided into m first discharge sections, where m is an
integer satisfying m.gtoreq.2, and the second discharge chamber is
divided into m second discharge sections. N out of the first
discharge sections, where n is an arbitrary integer satisfying
1.ltoreq.n<m, are defined as specified first discharge sections,
and n out of the second discharge sections are defined as specified
second discharge sections. When viewed from an axial direction of
the drive shaft, at least one of the specified first discharge
sections and at least one of the specified second discharge
sections are disposed at positions shifted from each other. N first
discharge passages each communicates with each of the specified
first discharge sections and the merging portion, and n second
discharge passages each communicates with each of the specified
second discharge sections and the merging portion.
Inventors: |
FUJIWARA; Shohei;
(Kariya-shi, JP) ; SUZUKI; Takahiro; (Kariya-shi,
JP) ; YAMAMOTO; Shinya; (Kariya-shi, JP) ;
OGAWA; Hiromichi; (Kariya-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KABUSHIKI KAISHA TOYOTA JIDOSHOKKI |
Kariya-shi |
|
JP |
|
|
Assignee: |
KABUSHIKI KAISHA TOYOTA
JIDOSHOKKI
Kariya-shi
JP
|
Family ID: |
56622041 |
Appl. No.: |
15/040050 |
Filed: |
February 10, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04B 27/0891 20130101;
F04B 27/12 20130101; F04B 27/1045 20130101; F04B 27/02 20130101;
F04B 27/1009 20130101; F04B 27/1054 20130101; F04B 27/1081
20130101 |
International
Class: |
F04B 53/00 20060101
F04B053/00; F04B 27/10 20060101 F04B027/10; F04B 27/12 20060101
F04B027/12; F04B 27/02 20060101 F04B027/02 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 12, 2015 |
JP |
2015-025762 |
Claims
1. A double-headed piston type compressor comprising: a drive
shaft; a housing that rotatably supports the drive shaft and has m
first cylinder bores, where m is an integer satisfying m.gtoreq.2,
at one side of the drive shaft and m second cylinder bores facing
the respective first cylinder bores at the other side of the drive
shaft; m double-headed pistons that reciprocate in the respective
first and second cylinder bores by rotation of the drive shaft; a
first discharge chamber that is formed into an annular shape in the
housing and into which refrigerant compressed in the first cylinder
bores is discharged; a second discharge chamber that is formed into
an annular shape in the housing and into which refrigerant
compressed in the second cylinder bores is discharged; a merging
portion in which the refrigerant discharged into the first
discharge chamber and the refrigerant discharged into the second
discharge chamber merge together, the merging portion being capable
of discharging the merged refrigerant to the outside; at least one
first discharge passage that provides communication between the
first discharge chamber and the merging portion; and at least one
second discharge passage that provides communication between the
second discharge chamber and the merging portion, wherein the first
discharge chamber is divided into m first discharge sections that
correspond to the respective first cylinder bores, the second
discharge chamber is divided into m second discharge sections that
correspond to the respective second cylinder bores, n out of the
first discharge sections, where n is an arbitrary integer
satisfying 1.ltoreq.n<m, are defined as specified first
discharge sections, n out of the second discharge sections are
defined as specified second discharge sections, when viewed from an
axial direction of the drive shaft, at least one of the specified
first discharge sections and at least one of the specified second
discharge sections are disposed at positions shifted from each
other, the at least one first discharge passage is n in number and
each communicates with each of the specified first discharge
sections and the merging portion, and the at least one second
discharge passage is n in number and each communicates with each of
the specified second discharge sections and the merging
portion.
2. The double-headed piston compressor according to claim 1,
Wherein, when viewed from the axial direction of the drive shaft,
all of the specified first discharge sections and all of the
specified second discharge sections are disposed at positions
shifted from one another.
3. The double-headed piston type compressor according to claim 2,
wherein m is an odd number satisfying m.gtoreq.3, and n=1.
4. The double-headed piston type compressor according to claim 3,
wherein the specified first discharge section is located apart from
the specified second discharge section by at least an integer
multiple of 360.degree./m around an axis of the drive shaft.
5. The double-headed piston type compressor according to claim 4,
wherein the specified first discharge section is located most apart
from the specified second discharge section across the axis of the
drive shaft.
6. The double-headed piston type compressor according to claim 3,
wherein the first discharge passage and the second discharge
passage are substantially equal in length.
7. The double-headed piston type compressor according to claim 1,
wherein the first discharge passage, the second discharge passage
and the merging portion are formed in the housing.
Description
TECHNICAL FIELD
[0001] The present invention relates to a double-headed piston type
compressor.
BACKGROUND ART
[0002] Japanese Patent Laid-Open No. 10-103228 discloses a
conventional double-headed piston type compressor (hereinafter,
simply referred to as a compressor). The compressor comprises a
drive shaft, a housing that rotatably supports the drive shaft, and
five double-headed pistons.
[0003] The housing has five first cylinder bores and five second
cylinder bores. The first cylinder bores are disposed at one side
of the drive shaft. The second cylinder bores are disposed at the
other side of the drive shaft and face the respective first
cylinder bores. The double-headed pistons reciprocate in the first
cylinder bores and the second cylinder bores respectively.
[0004] The housing has also an annular first discharge chamber, an
annular second discharge chamber, a merging portion, a first
discharge passage and a second discharge passage. Refrigerant that
has been compressed in the respective first cylinder bores is
discharged into the first discharge chamber. Refrigerant that has
been compressed in the respective second cylinder bores is
discharged into the second discharge chamber. The refrigerant
discharged into the first discharge chamber and the refrigerant
discharged into the second discharge chamber flow into and merge
together in the merging portion. The merging portion is capable of
discharging the merged refrigerant to the outside. The first
discharge passage provides communication between the first
discharge chamber and the merging portion. The second discharge
passage provides communication between the second discharge chamber
and the merging portion.
[0005] In this compressor, when the respective double-headed
pistons reciprocate by rotation of the drive shaft, the refrigerant
that has been compressed in the respective first cylinder bores is
successively discharged into the first discharge chamber and
reaches the merging portion through the first discharge passage,
and the refrigerant that has been compressed in the respective
second cylinder bores is successively discharged into the second
discharge chamber and reaches the merging portion through the
second discharge passage. Then, the refrigerant from the first
discharge chamber merges with the refrigerant from the second
discharge chamber in the merging portion, and the merged
refrigerant is discharged outside. At this time, pressures in the
first and second discharge chambers momentarily increase at every
discharge, and this causes discharge pulsation. When the discharge
pulsation is analyzed using a fast Fourier transform (FFT), it is
found that the pulsation includes various frequency components from
a first-order to quite a high-order of rotation components. If the
refrigerant is discharged outside from the merging portion without
reducing the discharge pulsation, components in a refrigeration
circuit such as a condenser vibrate and noise is generated.
[0006] In this regard, in this compressor, among the frequency
components of the discharge pulsation, the fifth-order rotation
component corresponding to the number (five) of the double-headed
pistons (where, the fifth-order rotation component is a five-cycle
fluctuation component during one rotation of the drive shaft) in
the first discharge chamber differ in phase by 180.degree. from the
fifth-order rotation component in the second discharge chamber.
Therefore, in the merging portion, the refrigerant which has passed
through the first discharge passage merges with the refrigerant
which has passed through the second discharge passage in a state
where the phases of their fifth-order rotation components are
shifted from each other, and this reduces the amplitude of
fifth-order rotation component in the merging portion.
[0007] Furthermore, in this compressor, countermeasures are taken
against other factors that may increase the fifth-order rotation
component. That is, the timing of discharging the refrigerant from
any one of the first cylinder bores is made different from any of
the timing of discharging the refrigerant from the respective
second cylinder bores. In addition, in this compressor, a pair of
pulsation reducing means are provided; one consisting of the first
discharge chamber and the first discharge passage, and the other
consisting of the second discharge chamber and the second discharge
passage. The pulsation reducing means are configured such that the
reduction rate of the discharge pulsation at one side of the drive
shaft is made equal to the reduction rate of the discharge
pulsation at the other side of the drive shaft in the housing. By
employing such a configuration, this compressor attempts to
reliably reduce the fifth-order rotation component of the discharge
pulsation.
[0008] The inventors of the present application intensively
analyzed various frequency components of discharge pulsations and
reached the findings that, in the case of employing the
configuration in which refrigerant compressed in the first and
second cylinder bores are respectively discharged into the annular
first and second discharge chambers, not only a m.sup.th-order
rotation component corresponding to the number m of double-headed
pistons, but also (m.+-.1).sup.th-order rotation components reach a
high level depending on the conditions at the time of operation and
become the factor of generating vibration and noise of the
refrigeration circuit unit. Furthermore, the inventors confirmed
that, with the conventional compressor described above, the
(m.+-.1).sup.th-order rotation components of the discharge
pulsation are difficult to reduce. That is, in the conventional
compressor, it is difficult to reliably reduce the vibration and
noise at the time of operation.
[0009] The present invention has been made in view of the
conventional situation described above, and an object of the
invention is to provide a double-headed piston type compressor
capable of reliably reducing vibration and noise at the time of
operation.
SUMMARY OF THE INVENTION
[0010] A double-headed piston type compressor of the present
invention comprises: a drive shaft; a housing that rotatably
supports the drive shaft and has m first cylinder bores, where m is
an integer satisfying m.gtoreq.2, at one side of the drive shaft
and m second cylinder bores facing the respective first cylinder
bores at the other side of the drive shaft; m double-headed pistons
that reciprocate in the respective first and second cylinder bores
by rotation of the drive shaft; a first discharge chamber that is
formed into an annular shape in the housing and into which
refrigerant compressed in the first cylinder bores is discharged; a
second discharge chamber that is formed into an annular shape in
the housing and into which refrigerant compressed in the second
cylinder bores is discharged; a merging portion in which the
refrigerant discharged into the first discharge chamber and the
refrigerant discharged into the second discharge chamber merge
together, the merging portion being capable of discharging the
merged refrigerant to the outside; at least one first discharge
passage that provides communication between the first discharge
chamber and the merging portion; and at least one second discharge
passage that provides communication between the second discharge
chamber and the merging portion. The first discharge chamber is
divided into m first discharge sections that correspond to the
respective first cylinder bores. The second discharge chamber is
divided into m second discharge sections that correspond to the
respective second cylinder bores. N out of the first discharge
sections, where n is an arbitrary integer satisfying
1.ltoreq.n<m, are defined as specified first discharge sections,
and n out of the second discharge sections are defined as specified
second discharge sections. When viewed from an axial direction of
the drive shaft, at least one of the specified first discharge
sections and at least one of the specified second discharge
sections are disposed at positions shifted from each other. The at
least one first discharge passage is n in number and each
communicates with each of the specified first discharge sections
and the merging portion. The at least one second discharge passage
is n in number and each communicates with each of the specified
second discharge sections and the merging portion.
[0011] Other aspects and advantages of the present invention will
be apparent from the embodiments disclosed in the following
description and the attached drawings, the illustrations
exemplified in the drawings, and the concept of the invention
disclosed in the entire description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 shows a sectional view of a compressor according to
Embodiment 1.
[0013] FIG. 2 relates to the compressor according to Embodiment 1,
showing a sectional view taken along line A-A of FIG. 1.
[0014] FIG. 3 relates to the compressor according to Embodiment 1,
showing a sectional view taken along line B-B of FIG. 1.
[0015] FIG. 4 relates to the compressor according to Embodiment 1,
showing a schematic perspective view of a first discharge chamber,
a second discharge chamber, a merging portion, a first discharge
passage, and a second discharge passage.
[0016] FIG. 5 relates to the compressor according to Embodiment 1
and is a series of graphs showing fifth-order rotation components
of discharge pulsations in the first and second discharge
chamber.
[0017] FIG. 6 relates to the compressor according to Embodiment 1
and is a series of graphs showing fourth-order rotation components
of the discharge pulsations in the first and second discharge
chambers.
[0018] FIG. 7 relates to the compressor according to Embodiment 1
and is a series of graphs showing sixth-order rotation components
of the discharge pulsations in the first and second discharge
chambers.
[0019] FIG. 8 relates to the compressor according to Embodiment 1;
(A) is a graph showing a fourth-order rotation component of a
discharge pulsation in the merging portion; (B) is a graph showing
a fifth-order rotation component of the discharge pulsation in the
merging portion; and (C) is a graph showing a sixth-order rotation
component of the discharge pulsation in the merging portion.
[0020] FIG. 9 relates to a compressor of a comparative example; (A)
is a graph showing a fourth-order rotation component of a discharge
pulsation in a merging portion; (B) is a graph showing a
fifth-order rotation component of the discharge pulsation in the
merging portion; and (C) is a graph showing a sixth-order rotation
component of the discharge pulsation in the merging portion.
[0021] FIG. 10 relates to a compressor according to Embodiment 2,
showing a schematic view of a first discharge chamber, a second
discharge chamber, a merging portion, a first discharge passage,
and a second discharge passage.
[0022] FIG. 11 relates to the compressor according to Embodiment 2;
(A) is a graph showing a fourth-order rotation component of a
discharge pulsation in the merging portion; (B) is a graph showing
a fifth-order rotation component of the discharge pulsation in the
merging portion; and (C) is a graph showing a sixth-order rotation
component of the discharge pulsation in the merging portion.
[0023] FIG. 12 relates to a compressor according to Embodiment 3,
showing a schematic view of a first discharge chamber, a second
discharge chamber, a merging portion, a first discharge passage,
and a second discharge passage.
[0024] FIG. 13 is shows a sectional view of a compressor according
to Embodiment 4.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0025] Hereinafter, Embodiments 1 to 4 of the present invention
will be described with reference to the drawings. The compressors
of Embodiments 1 to 4 are all mounted on vehicles and constitute
refrigeration circuits of air-conditioning apparatus for the
vehicles.
Embodiment 1
[0026] As shown in FIG. 1, the compressor in Embodiment 1 comprises
a housing 1, a drive shaft 3, a swash plate 5, and five
double-headed pistons 7.
[0027] The housing 1 has a first housing 11, a second housing 13, a
first cylinder block 15, a second cylinder block 17, a first valve
formation plate 19, and a second valve formation plate 21. In the
present embodiment, the front-rear direction of the compressor is
defined on the assumption that the side on which the first housing
11 is disposed is the front side of the compressor, and the side on
which the second housing 13 is disposed is the rear side of the
compressor. The front side of the compressor corresponds to "one
side of the drive shaft" in the present invention, and the rear
side of the compressor corresponds to "the other side of the drive
shaft" in the present invention.
[0028] The housing 1 is formed by aligning the first housing 11,
the first valve formation plate 19, the first cylinder block 15,
the second cylinder block 17, the second valve formation plate 21,
and the second housing 13 in this order from the front side to the
rear side of the compressor and joining them all together using
five through-bolts 14 shown in FIGS. 1 to 3.
[0029] As shown in FIG. 1, the first housing 11 has a boss 11a that
protrudes frontward. A shaft seal device 23 is provided in the boss
11a. As shown in FIGS. 1 and 2, a first suction chamber 25 and a
first discharge chamber 27 are formed in the first housing 11. The
first suction chamber 25 is disposed in a center portion of the
first housing 11. The first discharge chamber 27 is disposed at an
outer circumferential side of the first suction chamber 25, and is
formed into a substantially annular shape to surround the first
suction chamber 25. Furthermore, as shown in FIG. 1, the first
housing 11 has recesses 11b, in which front end portions of the
respective through-bolts 14 can be accommodated, and bolt holes 11c
that communicate with the recesses 11b.
[0030] As shown in FIGS. 1 and 3, a second suction chamber 26 and a
second discharge chamber 28 are formed in the second housing 13.
The second suction chamber 26 is disposed in a center portion of
the second housing 13. The second discharge chamber 28 is disposed
at an outer circumferential side of the second suction chamber 26,
and is formed into a substantially annular shape to surround the
second suction chamber 26. Furthermore, as shown in FIG. 1, the
second housing 13 has bolt holes 13a. The bolt holes 13a are formed
with threads (not illustrated) to be screwed with the through-bolts
14.
[0031] The first cylinder block 15 is disposed at the front side of
the second cylinder block 17 in the compressor. As shown in FIGS. 1
and 2, the first cylinder block 15 has five first cylinder bores
151 to 155 that extend in an axial direction, i.e., in the
direction of an axis O of the drive shaft 3. The first cylinder
bores 151 to 155 are arranged at equiangular intervals around the
axis O of the drive shaft 3.
[0032] As shown in FIG. 1, the first cylinder block 15 has a first
shaft hole 15a through which the drive shaft 3 is inserted. A first
radial bearing 29a is provided in the first shaft hole 15a.
Furthermore, the first cylinder block 15 has a first retainer
groove 15b that restricts the maximum opening degree of first
suction reed valves 191a, which will be described later, and also
has bolt holes 15c through which the through-bolts 14 are
inserted.
[0033] As shown in FIGS. 1 and 2, the first cylinder block 15 has
five first communication paths 31a. The first communication paths
31a are arranged at equiangular intervals around the axis O of the
drive shaft 3. Furthermore, the first cylinder block 15 has a first
connecting passage 33a. The first communication paths 31a and the
first connecting passage 33a all extend in the axial direction, and
front ends thereof are opened to a front end surface of the first
cylinder block 15. In FIG. 2, illustration of the first valve
formation plate 19 is omitted for ease of explanation.
[0034] As shown in FIG. 1, the second cylinder block 17 is disposed
at the rear side of first cylinder block 15 in the compressor. As
shown in FIGS. 1 and 3, the second cylinder block 17 has five
second cylinder bores 171 to 175 that extend in the axial
direction. The first cylinder bores 171 to 175 are arranged at
equiangular intervals around the axis O of the drive shaft 3, and
are respectively paired with the above described first cylinder
bores 151 to 155. Thereby, the first cylinder bore 151 faces the
second cylinder bore 171 in the direction of the axis O of the
drive shaft 3. Similarly, the first cylinder bores 152 to 155 face
the corresponding second cylinder bores 172 to 175 in the direction
of the axis O of the drive shaft 3.
[0035] As shown in FIG. 1, the second cylinder block 17 has a
second shaft hole 17a through which the drive shaft 3 is inserted.
A second radial bearing 29b is provided in the second shaft hole
17a. Furthermore, the second cylinder block 17 has a second
retainer groove 17b that restricts the maximum opening degree of
second suction reed valves 211a, which will be described later, and
also has bolt holes 17c through which the through-bolts 14 are
inserted.
[0036] As shown in FIGS. 1 and 3, the second cylinder block 17 has
five second communication paths 31b. The second communication paths
31b are arranged at equiangular intervals around the axis O of the
drive shaft 3. Furthermore, the second cylinder block 17 has a
second connecting passage 33b. The second communication paths 31b
and the second connecting passage 33b all extend in the axial
direction, and rear ends thereof are opened to a rear end surface
of the second cylinder block 17. In FIG. 3, illustration of the
second valve formation plate 21 is omitted for ease of
explanation.
[0037] As shown in FIG. 1, by joining the first cylinder block 15
and the second cylinder block 17 with each other, a swash plate
chamber 35, an inlet port 350, a connection passage 37, a merging
portion 39 and an outlet port 390 are formed therebetween.
[0038] The swash plate chamber 35 is disposed substantially at a
center of the housing 1 in the front-rear direction of the
compressor. Rear ends of the first communication paths 31a and
front ends of the second communication paths 31b respectively
communicate with the swash plate chamber 35. The inlet port 350
also communicates with the swash plate chamber 35.
[0039] In FIG. 1, the first connecting passage 33a, the second
connecting passage 33b, the connection passage 37 and the merging
portion 39 are schematically illustrated, and the actual shapes
thereof are as shown in FIG. 4. That is, the connection passage is
formed into a circular arc shape and extends in a circumferential
direction of the housing 1. One end of the connection passage 37 is
connected to a rear end of the first connecting passage 33a, and
the other end of the connection passage 37 is connected to a front
end of the second connecting passage 33b. Furthermore, the merging
portion 39 is connected to a center of the connection passage 37 in
the circumferential direction.
[0040] In this configuration, the connection passage 37 is divided
into the following two portions: a first portion 37a, which is the
portion extending from the position where the first connecting
passage 33a is connected to the position where the merging portion
39 is connected; and a second portion 37b, which is the portion
extending from the position where the second connecting passage 33b
is connected to the position where the merging portion 39 is
connected. In this compressor, the first connecting passage 33a and
the first portion 37a of the connection passage 37 form a first
discharge passage 41. Similarly, the second connecting passage 33b
and the second portion 37b of the connection passage 37 forma
second discharge passage 43.
[0041] In the present embodiment, a length L1, which is the length
of the first connecting passage 33a, and a length L2, which is the
length of the second connecting passage 33b, are made equal.
Furthermore, a length L3, which is the length of the first portion
37a of the connection passage 37, and a length L4, which is the
length of the second portion 37b of the connection passage 37, are
also made equal. Accordingly, the length of the first discharge
passage 41 (L1+L3) and the length of the second discharge passage
43 (L2+L4) are equal.
[0042] As shown in FIG. 1, the first valve formation plate 19 is
disposed between the first housing 11 and the first cylinder block
15. The first valve formation plate 19 has a first valve plate 190,
a first suction valve plate 191, a first discharge valve plate 192
and a first retainer plate 193. The first valve formation plate 19
is provided with a first discharge communication hole 190a and five
first suction communication holes 190b. Furthermore, the first
valve formation plate 19 is also provided with a communication hole
190c and bolt holes 190d. Additionally, although not illustrated,
the first valve formation plate 19 is also provided with five first
suction ports and five first discharge ports that respectively
correspond to the first cylinder bores 151 to 155.
[0043] The first suction valve plate 191 is provided on the rear
surface of the first valve plate 190. The five first suction reed
valves 191a, which can open and close the respective first suction
ports by elastic deformation, are formed on the first suction valve
plate 191. The first discharge valve plate 192 is provided on the
front surface of the first valve plate 190. Five first discharge
reed valves 192a, which can open and close the respective first
discharge ports by elastic deformation, are formed on the first
discharge valve plate 192. The first retainer plate 193 is provided
on the front surface of the first discharge valve plate 192. The
first retainer plate 193 restricts the maximum opening degree of
the first discharge reed valves 192a.
[0044] The first cylinder bores 151 to 155 shown in FIG. 2
communicate with the first suction chamber 25 through the
respective first suction ports (not illustrated) and communicate
also with the first discharge chamber 27 through the respective
first discharge ports (not illustrated). As shown in FIG. 2, the
first discharge chamber 27 of the present embodiment is divided
into first to fifth front side discharge sections 271 to 275
equiangularly around the axis O of the drive shaft 3 so as to
correspond to the respective first cylinder bores 151 to 155. The
first to fifth front side discharge sections 271 to 275 correspond
to first discharge sections in the present invention.
[0045] Specifically, the first front side discharge section 271
corresponds to the first cylinder bore 151; the second front side
discharge section 272 corresponds to the first cylinder bore 152;
the third front side discharge section 273 corresponds to the first
cylinder bore 153; the fourth front side discharge section 274
corresponds to the first cylinder bore 154; and the fifth front
side discharge section 275 corresponds to the first cylinder bore
155.
[0046] As shown in FIG. 2, when viewed from the direction of the
axis O of the drive shaft 3, the first connecting passage 33a is
provided at a position overlapping with the first front side
discharge section 271 of the first discharge chamber 27. The first
connecting passage 33a communicates with the first front side
discharge section 271 through the first discharge communication
hole 190a shown in FIG. 1. Thereby, as shown in FIG. 4, the first
discharge chamber 27 communicates with the first discharge passage
41 at the first front side discharge section 271. Among the first
to fifth front side discharge sections 271 to 275, the first front
side discharge section 271 corresponds to a specified first
discharge section in the present invention.
[0047] As shown in FIG. 1, the first suction chamber 25
communicates with the respective first communication paths 31a
through the first suction communication holes 190b and thus
communicates with the swash plate chamber 35. Therefore, the
pressure in the swash plate chamber 35 is substantially equal to
the pressure in the first suction chamber 25. The drive shaft 3 is
inserted through the insertion hole 190c, and the bolts 14 are
inserted through the bolt holes 190d.
[0048] The second valve formation plate 21 is disposed between the
second housing 13 and the second cylinder block 17. The second
valve formation plate 21 has a second valve plate 210, a second
suction valve plate 211, a second discharge valve plate 212 and a
second retainer plate 213. The second valve formation plate 21 is
provided with a second discharge communication hole 210a and five
second suction communication holes 210b. Furthermore, the second
valve formation plate 21 is also provided with bolt holes 210c.
Additionally, although not illustrated, the second valve formation
plate 21 is also provided with five second suction ports and five
second discharge ports that respectively correspond to the second
cylinder bores 171 to 175.
[0049] The second suction valve plate 211 is provided on the front
surface of the second valve plate 210. The five second suction reed
valves 211a, which can open and close the respective second suction
ports by elastic deformation, are formed on the second suction
valve plate 211. The second discharge valve plate 212 is provided
on the rear surface of the second valve plate 210. Five second
discharge reed valves 212a, which can open and close the respective
second discharge ports by elastic deformation, are formed on the
second discharge valve plate 212. The second retainer plate 213 is
provided on the rear surface of the second discharge valve plate
212. The second retainer plate 213 restricts the maximum opening
degree of the second discharge reed valves 212a.
[0050] The respective second cylinder bores 171 to 175 shown in
FIG. 3 communicate with the second suction chamber 26 through the
respective second suction ports (not illustrated) and communicate
with the second discharge chamber 28 through the respective second
discharge ports (not illustrated). As shown in FIG. 3, the second
discharge chamber 28 of the present embodiment is divided into a
first to fifth rear side discharge sections 281 to 185
equiangularly around the axis O of the drive shaft 3 so as to
correspond to the respective second cylinder bores 171 to 175. The
first to fifth rear side discharge sections 281 to 285 correspond
to second discharge sections in the present invention.
[0051] Specifically, the second rear side discharge section 281
corresponds to the second cylinder bore 171; the second rear side
discharge section 282 corresponds to the second cylinder bore 172;
the third rear side discharge section 283 corresponds to the second
cylinder bore 173; the fourth rear side discharge section 284
corresponds to the second cylinder bore 174; and the fifth rear
side discharge section 285 corresponds to the second cylinder bore
175.
[0052] As shown in FIG. 3, when viewed from the direction of the
axis O of the drive shaft 3, the second connecting passage 33b is
provided at a position overlapping with the third rear side
discharge section 283 of the second discharge chamber 28. The
second connecting passage 33b communicates with the third rear side
discharge section 283 through the second discharge communication
hole 210a shown in FIG. 1. Thereby, as shown in FIG. 4, the second
discharge chamber 28 communicates with the second discharge passage
43 at the third rear side discharge section 283. Among the first to
fifth rear side discharge sections 281 to 285, the third rear side
discharge section 283 corresponds to a specified second discharge
section in the present invention.
[0053] As shown in FIG. 4, when the first discharge chamber 27 and
the second discharge chamber 28 are viewed from the direction of
the axis O of the drive shaft 3, the first front side discharge
section 271 is located at a position facing the first rear side
discharge section 281. Similarly, the second front side discharge
section 272, the third front side discharge section 273, the fourth
front side discharge section 274, and the fifth front side
discharge section 275 are located at positions facing the second
rear side discharge section 282, the third rear side discharge
section 283, the fourth rear side discharge section 284, and the
fifth rear side discharge section 285, respectively.
[0054] The first front side discharge section 271 is located apart
from the third rear side discharge section 283 by 144.degree.,
which is twice as large as 360.degree./5, in the direction of the
dashed arrow R1 in FIG. 4 around the axis O of the drive shaft 3.
That is, the first front side discharge section 271 is most apart
from the third rear side discharge section 283 across the axis O of
the drive shaft 3 in the direction of the dashed arrow R1. In other
words, when the first discharge chamber 27 and the second discharge
chamber 28 are viewed from the direction of the axis O of the drive
shaft 3, the first front side discharge section 271 and the third
rear side discharge section 283 are disposed at positions shifted
from each other. Consequently, in this compressor, when viewed from
the direction of the axis O, the position where the first
connecting passage 33a of the first discharge passage 41
communicates with the first front side discharge section 271 of the
first discharge chamber 27 is shifted from the position where the
second connecting passage 33b of the second discharge passage 43
communicates with the third rear side discharge section 283 of the
second discharge chamber 28.
[0055] As shown in FIG. 1, the second suction chamber 26
communicates with the respective second communication paths 31b
through the second suction communication holes 210b and thus
communicates with the swash plate chamber 35. Therefore, the
pressure in the swash plate chamber 35 is also substantially equal
to the pressure in the second suction chamber 26. The bolts 14 are
inserted through the bolt holes 210c.
[0056] The drive shaft 3 is inserted into the housing 1 so as to
extend in the direction of the axis O. A front side of the drive
shaft 3 is inserted through the shaft seal device 23 in the boss
11a and supported by the first radial bearing 29a in the first
shaft hole 15a of the first cylinder block 15. A rear side of the
drive shaft 3 is supported by the second radial bearing 29b in the
second shaft hole 17a of the second cylinder block 17. The housing
1 supports the drive shaft 3 so as to be rotatable around the axis
O of the drive shaft 3.
[0057] A threaded portion 3a is formed at a front end of the drive
shaft 3. The drive shaft 3 is connected to a pulley or an
electromagnetic clutch (not illustrated) via the threaded portion
3a.
[0058] The swash plate 5 includes a cylindrical portion 5a and a
swash plate main body 5b. An insertion hole 5c is formed through
the cylindrical portion 5a. The swash plate main body 5b is formed
into a plate shape and has a front surface 501 and a rear surface
502. The swash plate main body 5b is inclined at a predetermined
angle with respect to the axis O of the drive shaft 3 and formed
integrally with the cylindrical portion 5a. By press-fitting the
drive shaft 3 to the insertion hole 5c, the swash plate 5 is
integrated with the drive shaft 3 and rotatable in the swash plate
chamber 35 along with the rotation of the drive shaft 3.
[0059] In the swash plate chamber 35, a first thrust bearing 45a is
provided between the swash plate 5 and the first cylinder block 15.
Furthermore, in the swash plate chamber 35, a second thrust bearing
45b is provided between the swash plate 5 and the second cylinder
block 17. The first thrust bearing 45a receives a frontward thrust
force acting on the drive shaft 3 at the time of operation of the
compressor, and the second thrust bearing 45b receives a rearward
thrust force acting on the drive shaft 3 at the time of operation
of the compressor.
[0060] The double-headed pistons 7 each has a first head portion 7a
at a front end thereof a second head portion 7b at a rear end
thereof. The first head portions 7a are reciprocally accommodated
in the respective first cylinder bores 151 to 155. First
compression chambers 47a are defined by the respective first head
portions 7a and the first valve formation plate 19 within the first
cylinder bores 151 to 155. The second head portions 7b are
reciprocally accommodated in the respective second cylinder bores
171 to 175. Second compression chambers 47b are defined by the
respective second head portions 7b and the second valve formation
plate 21 within the second cylinder bores 171 to 175.
[0061] The double-headed pistons 7 each has an engaging portion 7c
at a center thereof. Semispherical shoes 49a and 49b are provided
in the respective engaging portions 7c. The shoes 49a slide on the
front surface 501 of the swash plate main body 5b. The shoes 49b
slide on the rear surface 502 of the swash plate main body 5b. In
this way, the shoes 49a and 49b convert rotation of the swash plate
5 into reciprocation of the double-headed pistons 7. Therefore,
when the drive shaft 3 rotates, the first head portions 7a of the
respective double-headed pistons 7 reciprocate in the respective
first cylinder bores 151 to 155, and the second head portions 7b
reciprocate in the respective second cylinder bores 171 to 175.
[0062] In this compressor, a pipe 201, which is connected to a
condenser 101, is connected to the outlet port 390. The condenser
101 is connected to an evaporator 102 via a pipe 202. Furthermore,
an expansion valve 103 is provided on the pipe 202. The evaporator
102 and the inlet port 350 are connected via a pipe 203. In this
manner, the refrigeration circuit of vehicle air-conditioning
apparatus is configured. Detailed explanation on configurations of
the condenser 101, the evaporator 102, the expansion valve 103, and
the pipes 201 to 203 are omitted.
[0063] In the compressor configured as above, by rotation of the
drive shaft 3, the swash plate 5 rotates and the double-headed
pistons 7 reciprocate in the first cylinder bores 151 to 155 and
the second cylinder bores 171 to 175. At this time, a suction phase
for sucking refrigerant gas that has passed through the evaporator
102 into the compression chambers 47a and 47b of the first cylinder
bores 151 to 155 and the second cylinder bores 171 to 175
respectively, a compression phase for compressing the refrigerant
gas in the first and second compression chambers 47a and 47b, and a
discharge phase for discharging the compressed high-pressure
refrigerant gas into the first and second discharge chambers 27 and
28 take place repeatedly. The high-pressure refrigerant gas
discharged into the first and second discharge chambers 27 and 28
reaches the merging portion 39 through the first and second
discharge passages 41 and 43 and is then discharged to the
condenser 101 through the outlet port 390.
[0064] More specifically, in this compressor, by rotation of the
drive shaft 3, the high-pressure refrigerant gas compressed in the
compression chamber 47a of the first cylinder bore 151 is
discharged into the first front side discharge section 271 of the
first discharge chamber 27. Subsequently, the high-pressure
refrigerant gas compressed in the compression chamber 47a of the
first cylinder bore 152 is discharged into the second front side
discharge section 272. Subsequently, the high-pressure refrigerant
gas compressed in the compression chamber 47a of the first cylinder
bore 153 is discharged into the third front side discharge section
273. Subsequently, the high-pressure refrigerant gas compressed in
the compression chamber 47a of the first cylinder bore 154 is
discharged into the fourth front side discharge section 274.
Subsequently, the high-pressure refrigerant gas compressed in the
compression chamber 47a of the first cylinder bore 155 is
discharged to the fifth front side discharge section 275.
Discharging operation is repeated in this order.
[0065] Similarly, by rotation of the drive shaft 3, the
high-pressure refrigerant gas compressed in the compression chamber
47b of the second cylinder bore 171 is discharged into the first
rear side discharge section 281. Subsequently, the high-pressure
refrigerant gas compressed in the compression chamber 47b of the
second cylinder bore 172 is discharged into the second rear side
discharge section 282. Subsequently, the high-pressure refrigerant
gas compressed in the compression chamber 47b of the second
cylinder bore 173 is discharged into the third rear side discharge
section 283. Subsequently, the high-pressure refrigerant gas
compressed in the compression chamber 47b of the second cylinder
bore 174 is discharged into the fourth rear side discharge section
284. Subsequently, the high-pressure refrigerant gas compressed in
the compression chamber 47b of the second cylinder bore 175 is
discharged to the fifth rear side discharge section 285.
Discharging operation is repeated in this sequence.
[0066] During the discharging operation, the pressures in the first
and second discharge chambers 27 and 28 momentarily increase every
time the high-pressure refrigerant gas is discharged, and this
causes discharge pulsation. In this compressor, since the number of
the double-headed pistons 7 is five, a fifth-order rotation
component is the main component among various frequency components
of the discharge pulsation. As shown in FIG. 5, the fifth-order
rotation component on the side of the first discharge chamber 27
differs in phase by 180.degree. from the fifth-order rotation
component on the side of the second discharge chamber 28.
Accordingly, when, for example, the phase of the fifth-order
rotation component of the high-pressure refrigerant gas discharged
from the first front side discharge section 271 of the first
discharge chamber 27 and flowing into the merging portion 39
through the first discharge passage 41 corresponds to the point A1
in FIG. 5 at a certain point in time, the phase of the fifth-order
rotation component of the high-pressure refrigerant gas discharged
from the third rear side discharge section 283 of the second
discharge chamber 28 and flowing into the merging portion 39
through the second discharge passage 43 corresponds to the point A2
in FIG. 5. Therefore, in this compressor, the high-pressure
refrigerant gas from the first discharge passage 41 merges with the
high-pressure refrigerant gas from the second discharge passage 43
in the merging portion 39 in a state where the phases of their
fifth-order rotation components differ from each other by
180.degree., and this reduces the amplitude of the fifth-order
rotation component of the discharge pulsation in the merging
portion 39 as shown in FIG. 8(B). As compared with the fifth-order
rotation components in the first and second discharge chambers 27
and 28 shown in FIG. 5, the amplitude of the fifth-order rotation
component in the merging portion 39 is surely reduced to almost
zero.
[0067] In this compressor, since the number of the double-headed
pistons 7 is an odd number, the timing of discharging the
high-pressure refrigerant gas from any one of the compression
chambers 47a of the first cylinder bores 151 to 155 differs from
any of the timing of discharging the high-pressure refrigerant gas
from the respective discharge chambers 47b of the second cylinder
bores 171 to 175. Furthermore, in this compressor, as shown in FIG.
4, the length of the first discharge passage 41 (L1+L3) is equal to
the length of the second discharge passage 43 (L2+L4). Accordingly,
the reduction rate of the discharge pulsations of the high-pressure
refrigerant gas is substantially equal between the first discharge
passage 41 and the second discharge passage 43. Therefore, even if
there are other factors which may increase the fifth-order rotation
component as described in Japanese Patent Laid-Open No. 10-103228,
the compressor of the present embodiment is capable of reliably
reduce the fifth-order rotation component of the discharge
pulsation.
[0068] Furthermore, in this compressor, the first and second
discharge chambers 27 and 28 are formed into the substantially
annular shapes. The high-pressure refrigerant gas compressed in the
compression chambers 47a of the first cylinder bores 151 to 155 is
discharged into the first discharge chamber 27. The high-pressure
refrigerant gas compressed in the compression chambers 47b of the
second cylinder bores 171 to 175 is discharged into the second
discharge chamber 28. In such a compressor, depending on the
conditions of operation, fourth-order rotation components of the
discharge pulsations in the first and second discharge chambers 27
and 28 also increases to a high level as shown in FIG. 6.
Similarly, depending on the conditions of operation, sixth-order
rotation components of the discharge pulsations in the first and
second discharge chambers 27 and 28 also increases to a high level
as shown in FIG. 7.
[0069] In this regard, as shown in FIG. 4, when the compressor is
viewed from the direction of the axis O of the drive shaft 3, the
position of the first front side discharge section 271 where the
first discharge passage 41 communicates with the first discharge
chamber 27 is shifted from the position of the third rear side
discharge section 283 where the second discharge passage 43
communicates with the second discharge chamber 28.
[0070] Accordingly, when, for example, the phase of the
fourth-order rotation component of the high-pressure refrigerant
gas discharged from the first front side discharge section 271 of
the first discharge chamber 27 and flowing into the merging portion
39 through the first discharge passage 41 corresponds to the point
B1 in FIG. 6 at a certain point in time, the phase of the
fourth-order rotation component of the high-pressure refrigerant
gas discharged from the third rear side discharge section 283 of
the second discharge chamber 28 and flowing into the merging point
39 through the second discharge passage 43 corresponds to the point
B2 in FIG. 6. Therefore, in the merging portion 39, the
high-pressure refrigerant gas which has flowed through the first
discharge passage 41 from the first front side discharge section
271 merges with the high-pressure refrigerant gas which has flowed
through the second discharge passage 43d from the third rear side
discharge section 283 in a state where the phases of their
fourth-order rotation components are shifted from each other, and
this reduces the amplitude of the fourth-order rotation component
of the discharge pulsation in the merging portion 39 as shown in
FIG. 8(A). As compared with the fourth-order rotation components in
the first and second discharge chambers 27 and 28 shown in FIG. 6,
the amplitude of the fourth-order rotation component in the merging
portion 39 is surely reduced.
[0071] Furthermore, when, for example, the phase of the sixth-order
rotation component of the high-pressure refrigerant gas discharged
from the first front side discharge section 271 of the first
discharge chamber 27 and flowing into the merging portion 39
through the first discharge passage 41 corresponds to the point C1
in FIG. 7 at a certain point in time, the phase of the sixth-order
rotation component of the high-pressure refrigerant gas discharged
from the third rear side discharge section 283 of the second
discharge chamber 28 and flowing into the merging portion 39
through the second discharge passage 43 corresponds to the point C2
in FIG. 7. Therefore, in the merging portion 39, the high-pressure
refrigerant gas which has flowed through the first discharge
passage 41 from the first front side discharge section 271 merges
with the high-pressure refrigerant gas which has flowed through the
second discharge passage 43 from the third rear side discharge
section 283 in a state where the phases of their sixth-order
rotation components are shifted from each other, and this reduces
the amplitude of the sixth-order rotation component of the
discharge pulsation in the merging portion 39 as shown in FIG.
8(C). As compared with the sixth-order rotation components in the
first and second discharge chambers 27 and 28 shown in FIG. 7, the
amplitude of the sixth-order rotation component in the merging
portion 39 is surely reduced.
[0072] A comparative example is shown in FIG. 9. In a compressor of
the comparative example, although not illustrated, the first
connecting passage 33a is connected to the first discharge chamber
27 at the first front side discharge section 271, and the second
connecting passage 33b is connected to the second discharge chamber
28 at the first rear side discharge section 281. That is, in the
compressor of the comparative example, the first front side
discharge section 271 is the first specified discharge section, and
the first rear side discharge section 281 is the second specified
discharge section. Therefore, when the compressor of the
comparative example is viewed from the direction of the axis O of
the drive shaft 3, the first front side discharge section 271 where
the first discharge passage 41 communicates with the first
discharge chamber 27 faces the first rear side discharge section
281 where the second discharge passage 43 communicates with the
second discharge chamber 28. The other configurations in the
compressor of the comparative example are the same as those of the
compressor in Embodiment 1.
[0073] Also In the compressor of the comparative example, the
fifth-order rotation component on the side of the first discharge
chamber 27 differs in phase by 180.degree. from the fifth-order
rotation component on the side of the second discharge chamber 28.
Accordingly, when, for example, the phase of the fifth-order
rotation component of the high-pressure refrigerant gas discharged
from the first front side discharge section 271 of the first
discharge chamber 27 and flowing into the merging portion 39
through the first discharge passage 41 corresponds to the point A1
in FIG. 5 at a certain point in time, the phase of the fifth-order
rotation component of the high-pressure refrigerant gas discharged
from the first rear side discharge section 281 of the second
discharge chamber 28 and flowing into the merging portion 39
through the second discharge passage 43 corresponds to the point A3
in FIG. 5. Therefore, the amplitude of the fifth-order rotation
component in the compressor of the comparative example is also
surely reduced to almost zero as shown in FIG. 9(B).
[0074] However, in the compressor of the comparative example, when,
for example, the phase of the fourth-order rotation component of
the high-pressure refrigerant gas discharged from the first front
side discharge section 271 of the first discharge chamber 27 and
flowing into the merging portion 39 through the first discharge
passage 41 corresponds to the point B1 in FIG. 6 at a certain point
in time, the phase of the fourth-order rotation component of the
high-pressure refrigerant gas discharged from the first rear side
discharge section 281 of the second discharge chamber 28 and
flowing into the merging portion 39 through the second discharge
passage 43 corresponds to the point B3 in FIG. 6. Therefore, in the
merging portion 39, the refrigerant gas which has flowed through
the first discharge passage 41 from the first front side discharge
section 271 merges with the high-pressure refrigerant gas which has
flowed through the second discharge passage 43 from the first rear
side discharge section 281 in a state where the phases of their
fourth-order rotation components overlap each other, and this
increases the amplitude of the fourth-order rotation component of
the discharge pulsation in the merging portion 39 as shown in FIG.
9(A). As compared with the fourth-order rotation components in the
first and second discharge chambers 27 and 28 shown in FIG. 6, the
amplitude of the fourth-order rotation component in the merging
portion 39 is significantly increased.
[0075] Furthermore, when, for example, the phase of the sixth-order
rotation component of the high-pressure refrigerant gas discharged
from the first front side discharge section 271 of the first
discharge chamber 27 and flowing into the merging portion 39
through the first discharge passage 41 corresponds to the point C1
in FIG. 7 at a certain point in time, the phase of the sixth-order
rotation component of the high-pressure refrigerant gas discharged
from the first rear side discharge section 281 of the second
discharge chamber 28 and flowing into the merging portion 39
through the second discharge passage 43 corresponds to the point C3
in FIG. 7. Therefore, in the merging portion 39, the high-pressure
refrigerant gas which has flowed through the first discharge
passage 41 from the first front side discharge section 271 merges
with the high-pressure refrigerant gas which has flowed through the
second discharge passage 43 from the first rear side discharge
section 281 in a state where the phases of their sixth-order
rotation components overlap each other, and this increases the
amplitude of the sixth-order rotation component of the discharge
pulsation in the merging portion 39 as shown in FIG. 9(C). As
compared with the sixth-order rotation components in the first and
second discharge chambers 27 and 28 shown in FIG. 7, the amplitude
of the sixth-order rotation component in the merging portion 39 is
significantly increased.
[0076] Since the compressor of Embodiment 1 is capable of reducing
the amplitudes of the fourth, fifth and sixth-order rotation
components in this way, it is possible to reduce the discharge
pulsation of the high-pressure refrigerant gas flowing into the
pipe 201 through the merging portion 39 and the outlet port
390.
[0077] Therefore, the compressor of Embodiment 1 is capable of
reliably reducing vibration and noise at the time of operation.
[0078] Furthermore, in this compressor, since the first discharge
passage 41, the second discharge passage 43, and the merging
portion 39 are formed in the housing 1, it is possible to simplify
the outer shape of the compressor as well as the assembly process
thereof.
Embodiment 2
[0079] In the compressor of Embodiment 2, as shown in FIG. 10, the
second discharge chamber 28 communicates with the second connecting
passage 33b and thus the second discharge passage 43 at the fifth
rear side discharge section 285. That is, in this compressor, the
fifth rear side discharge section 285 corresponds to the specified
second discharge section of the present invention.
[0080] In this compressor, the first front side discharge section
271 is located apart from the fifth rear side discharge section 285
by 72.degree., which is 360.degree./5, in the opposite direction of
the dashed arrow R1 in FIG. 4 around the axis O of the drive shaft
3. The other configurations in this compressor are the same as
those of the compressor of Embodiment 1. Where the components are
the same as Embodiment 1, same reference numerals are used and
detailed explanation thereof is omitted.
[0081] Also in this compressor, the fifth-order rotation component
of the discharge pulsation on the side of the first discharge
chamber 27 differs in phase by 180.degree. from the fifth-order
rotation component on the side of the second discharge chamber 28.
Accordingly, when, for example, the phase of the fifth-order
rotation component of the high-pressure refrigerant gas discharged
from the first front side discharge section 271 of the first
discharge chamber 27 and flowing into the merging portion 39
through the first discharge passage 41 corresponds to the point A1
in FIG. 5 at a certain point in time, the phase of the fifth-order
rotation component of the high-pressure refrigerant gas discharged
from the fifth rear side discharge section 285 of the second
discharge chamber 28 and flowing into the merging portion 39
through the second discharge passage 43 corresponds to the point A4
in FIG. 5. Therefore, the amplitude of the fifth-order rotation
component in this compressor is surely reduced to almost zero as
shown in FIG. 11(B).
[0082] Furthermore, in this compressor, when, for example, the
phase of the fourth-order rotation component of the high-pressure
refrigerant gas discharged from the first front side discharge
section 271 of the first discharge chamber 27 and flowing into the
merging portion 39 through the first discharge passage 41
corresponds to the point B1 in FIG. 6 at a certain point in time,
the phase of the fourth-order rotation component of the
high-pressure refrigerant gas discharged from the fifth rear side
discharge section 285 of the second discharge chamber 28 and
flowing into the merging portion 39 through the second discharge
passage 43 corresponds to the point B4 in FIG. 6. Therefore, in the
merging portion 39, the high-pressure refrigerant gas which has
flowed through the first discharge passage 41 from the first front
side discharge section 271 merges with the high-pressure
refrigerant gas which has flowed through the second discharge
passage 43 from the fifth rear side discharge section 285 in a
state where the phases of their fourth-order rotation components
are shifted from each other, and thereby, as shown in FIG. 11(A),
the degree of increase of the amplitude of the fourth-order
rotation component in the merging portion 39 can be made smaller
than that of the comparative example shown in FIG. 9(A).
[0083] Furthermore, when, for example, the phase of the sixth-order
rotation component of the high-pressure refrigerant gas discharged
from the first front side discharge section 271 of the first
discharge chamber 27 and flowing into the merging portion 39
through the first discharge passage 41 corresponds to the point C1
in FIG. 7 at a certain point in time, the phase of the sixth-order
rotation component of the high-pressure refrigerant gas discharged
from the fifth rear side discharge section 285 of the second
discharge chamber 28 and flowing into the merging portion 39
through the second discharge passage 43 corresponds to the point C4
in FIG. 7. Therefore, in the merging portion 39, the high-pressure
refrigerant gas which has flowed through the first discharge
passage 41 from the first front side discharge section 271 merges
with the high-pressure refrigerant gas which has flowed through the
second discharge passage 43 from the fifth rear side discharge
section 285 in a state where the phases of their sixth-order
rotation components are shifted from each other, and thereby, as
shown in FIG. 11(C), the degree of increase of the amplitude of the
sixth-order rotation component in the merging portion 39 can be
made smaller than that of the comparative example shown in FIG.
9(C).
[0084] Therefore, the compressor of Embodiment 2 is also capable of
reliably reducing vibration and noise at the time of operation.
Embodiment 3
[0085] Unlike the compressor of Embodiment 1, the compressor of
Embodiment 3 is provided with two first discharge passages 51a and
51b and two second discharge passages 53a and 53b as shown in FIG.
12.
[0086] The first discharge passage 51a communicates with the first
front side discharge section 271 in the first discharge chamber 27
and the merging portion 39. The first discharge passage 51b
communicates with the third front side discharge section 273 in the
first discharge chamber 27 and the merging portion 39.
[0087] The second discharge passage 53a communicates with the
second rear side discharge section 282 in the second discharge
chamber 28 and the merging portion 39. The second discharge passage
53b communicates with the fourth rear side discharge section 284 in
the second discharge chamber 28 and the merging portion 39.
[0088] The first front side discharge section 271 and the third
front side discharge section 273 correspond to the first specified
discharge section in the present invention. The second rear side
discharge section 282 and the fourth rear side discharge section
284 correspond to the second specified discharge section in the
present invention.
[0089] When viewed from the direction of the axis O of the drive
shaft 3, the first front side discharge section 271 and the third
front side discharge section 273, i.e., the first specified
discharge section, and the second rear side discharge section 282
and the fourth rear side discharge section 284, i.e., the second
specified discharge section, are disposed at positions shifted from
each other. The other configurations of this compressor are the
same as those of the compressor in Embodiment 1.
[0090] With the compressor of Embodiment 3 configured as above,
similarly to the compressors of Embodiments 1 and 2, it is possible
to reliably reduce vibration and noise at the time of
operation.
Embodiment 4
[0091] As shown in FIG. 13, the compressor of Embodiment 4 employs
a first discharge passage 55 and a second discharge passage 57
instead of the first discharge passage 41 and the second discharge
passage 43 in the compressor of Embodiment 1. In the present
embodiment, the first discharge passage 55, the second discharge
passage 57, and the merging portion 39 are disposed outside of the
housing 1. Furthermore, the first and second valve formation plates
19 and 21 in this embodiment do not have the first and second
discharge communication paths 190a and 210a provided in Embodiment
1.
[0092] The first discharge passage 55 communicates with the first
discharge chamber 27 at a front end 55a thereof and communicates
with the merging portion 39 at a rear end 55b thereof. Furthermore,
the second discharge passage 57 communicates with the merging
portion 39 a front end 57a thereof and communicates with the second
discharge chamber 28 a rear end 57b thereof. The front end 55a of
the first discharge passage 55 is connected to the first discharge
chamber 27 from outside of the first housing 11 at a position where
the first front side discharge section 271 is located. Similarly,
the rear end 57b of the second discharge passage 57 is connected to
the second discharge chamber 28 from outside of the second housing
13 at a position where the third rear side discharge section 283 is
located. The other configurations of this compressor are the same
as those of the compressor in Embodiment 1.
[0093] Similarly to the compressors of Embodiments 1 and 2, the
compressor of Embodiment 4 is also capable of reliably reducing
vibration and noise at the time of operation. Furthermore, in this
compressor, since the first discharge passage 55, the second
discharge passage 57, and the merging portion 39 do not need to be
formed in the first and second cylinder blocks 15 and 17,
configurations of the first and second cylinder blocks 15 and 17
can be simplified.
[0094] Although the present invention has been described in line
with the embodiments above, it is needless to say that the
invention is not limited to the above-described embodiments, but
may be appropriately modified in application without departing from
the gist of the invention.
[0095] For example, selection of the specified first discharge
section and the specified second discharge section is not limited
to those in Embodiments 1 to 4. The compressor of Embodiment 1 may
be configured such that the second discharge chamber 28
communicates with the second discharge passage 43 at the fourth
rear side discharge section 284. In this case, the first front side
discharge section 271 is located apart from the fourth rear side
discharge section 284 by 144.degree. in the opposite direction of
the dashed arrow R1 in FIG. 4 around the axis O of the drive shaft
3. Therefore, it is possible to exhibit the same effect as the
compressor of Embodiment 1.
[0096] Furthermore, although m=5 and n=1 in Embodiments 1, 2 and 4
and m=5 and n=2 in Embodiment 3, the present invention is not
limited to these configurations. In the present invention, the
numbers m and n may be freely selected as long as the compressor is
operable. For example, when m=5 and n=4, the compressor may be
configured such that, when viewed from the axial direction of the
drive shaft, one of the four specified first discharge sections and
one of the four specified second discharge sections are disposed at
positions shifted from each other, and the other three of the four
specified first discharge sections and the other three of the four
specified second discharge sections are disposed at positions
facing each other.
[0097] Furthermore, although the discharge capacity of the
compressors in Embodiments 1 to 4 is fixed at a constant value by
fixing the inclination angle of the swash plate main body 5b at a
predetermined value with respect to the axis O of the drive shaft
3, the swash plate 5 may be configured such that its inclination
angle with respect to the axis O of the drive shaft 3 is changeable
by pressure in the swash plate chamber 35 and an exclusive
actuator.
* * * * *