U.S. patent application number 12/845351 was filed with the patent office on 2011-02-03 for rotary compressor.
This patent application is currently assigned to FUJITSU GENERAL LIMITED. Invention is credited to Masaki Fujino, Taku Morishita, Naoya Morozumi, Junya Tanaka, Kenshi Ueda.
Application Number | 20110027117 12/845351 |
Document ID | / |
Family ID | 42732240 |
Filed Date | 2011-02-03 |
United States Patent
Application |
20110027117 |
Kind Code |
A1 |
Fujino; Masaki ; et
al. |
February 3, 2011 |
ROTARY COMPRESSOR
Abstract
According to one embodiment, a rotary compressor includes a
compressor housing, a compressing unit, a motor, and an oil supply
mechanism. The compressor housing has an inlet and an outlet of
refrigerant. The compressing unit compresses refrigerant sucked in
from the inlet. The motor drives the compressing unit through a
rotation shaft. The oil supply mechanism supplies lubricant oil to
the compressing unit through an oil supply hole of the rotation
shaft. The oil supply mechanism includes a housing hole, a pump
case, and a pump vane. The housing hole is communicated with the
oil supply hole. The pump case is fitted in the housing hole. The
pump vane is housed in the pump case, and includes a large width
portion which is locked by the upper inner surface of the pump
case.
Inventors: |
Fujino; Masaki; (Kanagawa,
JP) ; Tanaka; Junya; (Kanagawa, JP) ;
Morishita; Taku; (Kanagawa, JP) ; Ueda; Kenshi;
(Kanagawa, JP) ; Morozumi; Naoya; (Kanagawa,
JP) |
Correspondence
Address: |
MCDERMOTT WILL & EMERY LLP
600 13TH STREET, N.W.
WASHINGTON
DC
20005-3096
US
|
Assignee: |
FUJITSU GENERAL LIMITED
|
Family ID: |
42732240 |
Appl. No.: |
12/845351 |
Filed: |
July 28, 2010 |
Current U.S.
Class: |
418/88 ; 418/156;
418/64; 418/94 |
Current CPC
Class: |
F04C 23/008 20130101;
F04C 2230/60 20130101; F04C 18/3564 20130101; F04C 29/025
20130101 |
Class at
Publication: |
418/88 ; 418/64;
418/94; 418/156 |
International
Class: |
F01C 21/04 20060101
F01C021/04; F01C 1/063 20060101 F01C001/063; F01C 5/00 20060101
F01C005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 31, 2009 |
JP |
2009-179690 |
Claims
1. A rotary compressor comprising: a hollow compressor housing that
is provided with an inlet and an outlet of refrigerant; a
compressing unit that is located in a lower part of the compressor
housing to compress refrigerant sucked in from the inlet; a motor
that is located in an upper part of the compressor housing to drive
the compressing unit through a rotation shaft; and an oil supply
mechanism that supplies lubricant oil retained in a lower part of
the compressor housing to a sliding portion of the compressing unit
through an oil supply hole of the rotation shaft, wherein the oil
supply mechanism includes a housing hole that has an opening in a
lower end of the rotation shaft and is communicated with the oil
supply hole, a pump case that includes a lubricant oil inlet in a
lower end and an opening in an upper end, the pump case configured
to be fitted in the housing hole, and a pump vane that has a
plate-like shape and is housed in the housing hole and the pump
case, the pump vane including a large width portion at a
longitudinal center, which is locked by an upper inner surface of
the pump case.
2. The rotary compressor according to claim 1, wherein a
longitudinal end portion of the pump vane housed in the pump case
is configured to be in contact with an inner surface of the pump
case to position the pump vane.
3. The rotary compressor according to claim 2, wherein a
longitudinal end portion of the pump vane housed in the housing
hole is separate from an inner surface of the housing hole.
4. The rotary compressor according to claim 1, wherein the
longitudinal center of the pump vane bulges in at least one width
direction to form a bulge that allows the large width portion to
have a width equal to or wider than an inner diameter of the pump
case.
5. The rotary compressor according to claim 4, wherein an inclined
portion is formed between the bulge and a side of the pump
vane.
6. The rotary compressor according to claim 1, wherein the pump
vane is twisted by a predetermined degree in a circumference
direction and is made of a material that allows the pump vane to be
elastically deformable in a direction in which the pump vane is
twisted.
7. The rotary compressor according to claim 1, wherein the pump
case is deformable at least in a radial direction.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application is based upon and claims the benefit of
priority of the prior Japanese Patent Application No. 2009-179690,
filed on Jul. 31, 2009, the entire contents of which are
incorporated herein by reference.
FIELD
[0002] The embodiments discussed herein are directed to a rotary
compressor.
BACKGROUND
[0003] A conventional rotary compressor is provided with a motor
and a compressing unit in the sealed housing. The compressing unit
is located below the motor and is driven by the motor. The
compressing unit includes a cylinder, an annular piston, and a
vane. The cylinder has an inlet and an outlet. The annular piston
is attached to an eccentric portion of the rotation shaft of the
motor to form an operation chamber the volume of which is variable.
The vane moves in and out of the operation chamber from the
cylinder and comes in contact with the annular piston, thereby
partitioning the operation chamber into an inlet chamber and a
compression chamber.
[0004] As the rotation shaft is rotated by the motor, the annular
piston revolves via the eccentric portion inside the cylinder.
Accordingly, gas refrigerant is sucked into the operation chamber
from the inlet. The gas refrigerant is compressed by reducing the
volume of the operation chamber. When the pressure reaches a
predetermined level, the compressed gas refrigerant is discharged
from the outlet, then passes through a gap in the motor as
high-pressure refrigerant, and is discharged out of the sealed
housing.
[0005] In the rotary compressor, lubricant oil is retained in the
lower part of the sealed housing. The lubricant oil is pumped up by
an oil supply mechanism and is supplied to the compressing unit for
lubrication. For example, Japanese unexamined utility model
application publication No. H06-049791 discloses a conventional
technology related to such an oil supply mechanism. According to
the conventional technology, in an oil supply device of a vertical
compressor, a hollow hole is formed in the core of a crankshaft. A
twisted pump vane is inserted in the hollow hole to pump up the
lubricant oil. The twisted pump vane is provided with a large width
portion wider than the inner diameter of the hollow hole. When
being inserted in the hollow hole of the crankshaft, the twisted
pump vane presses the inner wall of the hollow hole with the large
width portion and thus is reliably fixed.
[0006] In the conventional oil supply device of the vertical
compressor described above, first, the twisted pump vane is
inserted into the hollow hole of the crankshaft, and then a pump
case is inserted thereinto to cover the twisted pump vane. Thus,
the large width portion of the twisted pump vane comes in contact
with a stepped portion of the crankshaft and the upper end of the
pump case, and thereby the twisted pump vane is positioned.
However, when the pump case is inserted into the hollow hole of the
crankshaft, the upper end of the pump case may tightly press the
large width portion of the twisted pump vane and deform the twisted
pump vane (the large width portion).
SUMMARY
[0007] According to an aspect of the present invention, a rotary
compressor includes a hollow compressor housing, a compressing
unit, a motor, and an oil supply mechanism. The compressor housing
is provided with an inlet and an outlet of refrigerant. The
compressing unit is located in the lower part of the compressor
housing to compress refrigerant sucked in from the inlet. The motor
is located in the upper part of the compressor housing to drive the
compressing unit through a rotation shaft. The oil supply mechanism
supplies lubricant oil retained in the lower part of the compressor
housing to the sliding portion of the compressing unit through an
oil supply hole of the rotation shaft. The oil supply mechanism
includes a housing hole, a pump case, and a pump vane. The housing
hole has an opening in the lower end of the rotation shaft and is
communicated with the oil supply hole. The pump case includes a
lubricant oil inlet in the lower end and an opening in the upper
end. The pump case is configured to be fitted in the housing hole.
The pump vane has a plate-like shape and is housed in the housing
hole and the pump case. The pump vane includes a large width
portion at the longitudinal center, which is locked by the upper
inner surface of the pump case.
[0008] The object and advantages of the invention will be realized
and attained by means of the elements and combinations particularly
pointed out in the claims.
[0009] It is to be understood that both the foregoing general
description and the following detailed description are exemplary
and explanatory and are not restrictive of the invention, as
claimed.
BRIEF DESCRIPTION OF THE DRAWING(S)
[0010] FIG. 1 is a vertical cross-sectional view of a rotary
compressor according to an embodiment of the invention;
[0011] FIG. 2 is a cross-sectional view of a compressing unit of
the rotary compressor taking along line II-II in FIG. 1;
[0012] FIG. 3 is a cross-sectional view of an oil supply mechanism
of the rotary compressor illustrated in FIG. 1;
[0013] FIG. 4 is a cross-sectional view of the oil supply mechanism
taking along line IV-IV in FIG. 3;
[0014] FIG. 5 is a front view of a twisted pump vane of the rotary
compressor illustrated in FIG. 1 before twisted; and
[0015] FIG. 6 is a front view of the twisted pump vane after
twisted.
DESCRIPTION OF THE EMBODIMENT(S)
[0016] Exemplary embodiments of the present invention will be
described in detail with reference to the accompanying
drawings.
[0017] FIG. 1 is a vertical cross-sectional view of a rotary
compressor according to an embodiment of the invention.
[0018] FIG. 2 is a cross-sectional view of a compressing unit of
the rotary compressor taking along line II-II in FIG. 1.
[0019] FIG. 3 is a cross-sectional view of an oil supply mechanism
of the rotary compressor. FIG. 4 is a cross-sectional view of the
oil supply mechanism taking along line IV-IV in FIG. 3. FIG. 5 is a
front view of a twisted pump vane of the rotary compressor before
twisted. FIG. 6 is a front view of the twisted pump vane after
twisted.
[0020] As illustrated in FIGS. 1 and 2, the rotary compressor of
the embodiment comprises a compressor housing 11, a compressing
unit 12, a motor 13, and an oil supply mechanism 14. The compressor
housing 11 is a hollow sealed housing formed of a cylindrical
housing body 21, a cover 22 above the housing body 21, and a bottom
23 fixed to the lower end of the housing body 21. The compressing
unit 12 is located in the lower part of the compressor housing 11.
The compressing unit 12 compresses gas refrigerant sucked in, and
thereby discharges it as high-pressure refrigerant.
[0021] The motor 13 is located in the upper part of the compressor
housing 11. The motor 13 includes a starter 31 and a rotor 32. The
starter 31 is shrink fit to the inner periphery of the compressor
housing 11 to be fixed thereto. The starter 31 is spaced apart from
the center of the starter 31 by a predetermined distance, and is
shrink fit to a rotation shaft 33 to be fixed thereto. The rotation
shaft 33 extends downward and is mechanically connected to the
compressing unit 12. Thus, the motor 13 drives the compressing unit
12 via the rotation shaft 33.
[0022] The oil supply mechanism 14 functions as an oil supply pump,
and supplies lubricant oil retained in the lower part of the
compressor housing 11 to the sliding portion of the compressing
unit 12 through an oil supply hole 100 of the rotation shaft 33,
which will be described later.
[0023] In the following, the compressing unit 12 will be described
in detail. The compressing unit 12 comprises a first compressing
unit 41 and a second compressing unit 51. The first compressing
unit 41 is located above the second compressing unit 51. The first
compressing unit 41 and the second compressing unit 51 are of
basically the same configuration, and operate in a similar manner,
and are arranged one on top of the other.
[0024] The first compressing unit 41 includes a short cylindrical
first cylinder 42 at the outer periphery. The first cylinder 42 has
a circular first cylinder inner wall 42a that is formed concentric
with the rotation shaft 33 of the motor 13. Inside the first
cylinder 42 (the first cylinder inner wall 42a) is a first annular
piston 43 having a smaller outer diameter than the inner diameter
of the first cylinder 42. Between the first cylinder inner wall 42a
and a first piston outer wall 43a of the first annular piston 43, a
first operation chamber (compression space) 44 is defined and
formed. The first operation chamber 44 is capable of compressing
refrigerant sucked therein and discharges the compressed
refrigerant.
[0025] In the first cylinder 42, a first vane groove 45 is formed
from the first cylinder inner wall 42a along the radial direction
over the height of the first cylinder 42. A flat plate-like first
vane 46 is fitted in the first vane groove 45. The first vane 46 is
supported and biased by a first spring (not illustrated) attached
to the recess of the first vane groove 45 in a direction to
protrude into the first operation chamber 44.
[0026] Usually, the first vane 46 is biased by the first spring in
a direction to protrude from the first vane groove 45 into the
first operation chamber 44, and the end is in contact with the
outer periphery of the first annular piston 43. Accordingly, the
first operation chamber 44 is partitioned by the first vane 46 into
a first inlet chamber 44a and a first compression chamber 44b.
[0027] Further, in the first cylinder 42, a back pressure guide
passage 47 is formed to allow the recess of the first vane groove
45 to be communicated with the inside of the compressor housing 11
to apply a back pressure to the first vane 46 by the pressure of
compressed refrigerant. The first cylinder 42 is provided with a
first inlet 48 that allows the first inlet chamber 44a to be
communicated with the outside so that refrigerant can be sucked
into the first inlet chamber 44a from the outside.
[0028] On the other hand, as with the first compressing unit 41,
the second compressing unit 51 includes a short cylindrical second
cylinder 52 at the outer periphery. The second cylinder 52 has a
circular second cylinder inner wall that is formed concentric with
the rotation shaft 33 of the motor 13. Inside the second cylinder
52 (the second cylinder inner wall) is a second annular piston 53
having a smaller outer diameter than the inner diameter of the
second cylinder 52. Between the second cylinder inner wall and a
second piston outer wall of the second annular piston 53, a second
operation chamber (compression space) 54 is defined and formed. The
second operation chamber 54 is capable of compressing refrigerant
sucked therein and discharges the compressed refrigerant.
[0029] In the second cylinder 52, a second vane groove (not
illustrated) is formed from the second cylinder inner wall along
the radial direction over the height of the second cylinder 52. A
flat plate-like second vane (not illustrated) is fitted in the
second vane groove. The second vane is supported and biased by a
second spring (not illustrated) attached to the recess of the
second vane groove in a direction to protrude into the second
operation chamber 54.
[0030] Usually, the second vane is biased by the second spring in a
direction to protrude from the second vane groove into the second
operation chamber 54, and the end is in contact with the outer
periphery of the second annular piston 53. Accordingly, the second
operation chamber 54 is partitioned by the second vane into a
second inlet chamber 54a and a second compression chamber 54b.
[0031] Although not illustrated, in the second cylinder 52, a back
pressure guide passage is formed to allow the recess of the second
vane groove to be communicated with the inside of the compressor
housing 11 to apply a back pressure to the second vane by the
pressure of compressed refrigerant. The second cylinder 52 is
provided with a second inlet (not illustrated) that allows the
second inlet chamber 54a to be communicated with the outside so
that refrigerant can be sucked into the second inlet chamber 54a
from the outside.
[0032] A partition 61 is placed between the first cylinder 42 and
the second cylinder 52 so that the first compressing unit 41 and
the second compressing unit 51 operate independently in the
compressing unit 12. The partition 61 is arranged to define the
first operation chamber 44 and the second operation chamber 54. An
upper end plate 62 is arranged above the first cylinder 42 to close
the first operation chamber 44. Meanwhile, A lower end plate 63 is
arranged below the second cylinder 52 to close the second operation
chamber 54.
[0033] Thus, the upper end plate 62, the first cylinder 42, the
partition 61, the second cylinder 52, and the lower end plate 63
are in this order from the top to the bottom, and are integrally
fixed by a fixing bolt (not illustrated). The outer periphery of
the upper end plate 62 is fitted and fixed to the inner periphery
of the compressor housing 11.
[0034] An upper bearing 62a is formed at the center of the upper
end plate 62. The upper bearing 62a rotatably supports the rotation
shaft 33. A lower bearing 63a is formed at the center of the lower
end plate 63. The lower bearing 63a rotatably supports the rotation
shaft 33. The upper end plate 62 is provided with a plurality of
arc long through holes 62b that are formed at regular intervals in
the circumference direction at the outer periphery. Through the
through holes 62b, lubricant oil mixed with refrigerant in the
compressing unit 12 and discharged above the compressor housing 11
is separated from the refrigerant and returns to the lower part of
the compressor housing 11.
[0035] The rotation shaft 33 is provided on the end side (the lower
side) with a first eccentric portion 64 and a second eccentric
portion 65, the phase of which is shifted by 180.degree. to be
eccentric. The first eccentric portion 64 is slidably fitted to the
inside of the first annular piston 43 of the first compressing unit
41 and is rotatable. The second eccentric portion 65 is slidably
fitted to the inside of the second annular piston 53 of the second
compressing unit 51 and is rotatable.
[0036] Accordingly, when the rotation shaft 33 rotates, the first
and second eccentric portions 64 and 65 integrally rotate. Through
the first and second eccentric portions 64 and 65, the first and
second annular pistons 43 and 53 revolve and rotate. That is, when
the rotation shaft 33 rotates clockwise in FIG. 2, the first
eccentric portion 64 rotates in the same direction while sliding
against the first annular piston 43. The first annular piston 43
rotates counterclockwise in FIG. 2 so that the first piston outer
wall 43a moves along the first cylinder inner wall 42a while
rotating, and also revolves clockwise in FIG. 2. Similarly, when
the rotation shaft 33 rotates, the second eccentric portion 65
rotates in the same direction, and the second annular piston 53
rotates and revolves.
[0037] When the first and second annular pistons 43 and 53 rotate
and revolve, along with the movement of them, the first vane 46 and
the second vane (not illustrated) move back and forth. Accordingly,
along with the movement of the first and second annular pistons 43
and 53, the volume of the first inlet chamber 44a, the second inlet
chamber 54a, the first compression chamber 44b, and the second
compression chamber 54b continuously changes. As a result, the
first compressing unit 41 and the second compressing unit 51
continuously suck in refrigerant and compress it, thereby
discharging the compressed refrigerant.
[0038] An upper muffler cover 66 is fixed on the upper end plate 62
such that an upper muffler chamber 67 is formed between the upper
end plate 62 and the upper muffler cover 66. Formed in the upper
end plate 62 is a first outlet 68 that allows the first compression
chamber 44b of the first cylinder 42 to be communicated with the
upper muffler chamber 67. The first outlet 68 is provided with a
first outlet valve 69 that prevents the backflow of compressed
refrigerant. The upper muffler chamber 67 reduces the pressure
pulsation of discharged refrigerant.
[0039] A lower muffler cover 70 is fixed to the bottom of the lower
end plate 63 such that a lower muffler chamber 71 is formed between
the lower end plate 63 and the lower muffler cover 70. Formed in
the lower end plate 63 is a second outlet 72 that allows the second
compression chamber 54b of the second cylinder 52 to be
communicated with the lower muffler chamber 71. The second outlet
72 is provided with a second outlet valve 73 that prevents the
backflow of compressed refrigerant. The lower muffler chamber 71
reduces the pressure pulsation of discharged refrigerant.
[0040] Although not illustrated, in the outer peripheral wall of
the cylindrical compressor housing 11, first and second through
holes are formed to be separated from each other in the axial
direction. Besides, on the outer peripheral wall of the cylindrical
compressor housing 11, an accumulator 81 formed of an independent
cylindrical sealed housing is supported by an accumulator holder
(not illustrated) and an accumulator band 82. The top of the
accumulator 81 is connected to a system connecting pipe 83
connected to the low pressure side of the refrigeration cycle.
[0041] The bottom of the accumulator 81 is connected to an end of a
first inlet pipe 84 and a second inlet pipe 85. The first inlet
pipe 84 and the second inlet pipe 85 extend through the first and
second through holes of the compressor housing 11, and the other
end thereof is connected to each of the first inlet 48 and the
second inlet (not illustrated) of the first cylinder 42 and the
second cylinder 52 in the first compressing unit 41 and the second
compressing unit 51.
[0042] The compressor housing 11 is connected to an outlet pipe 86
that is connected to the high pressure side of the refrigeration
cycle to discharge high pressure refrigerant to the high pressure
side of the refrigeration cycle. That is, the first outlet 68 and
the second outlet 72 are communicated with the high pressure side
of the refrigeration cycle via the outlet pipe 86.
[0043] Lubricant oil is retained in the lower part of the
compressor housing 11. The oil supply mechanism 14 supplies the
lubricant oil to the sliding portion of the compressing unit 12
through the oil supply hole 100 of the rotation shaft. The oil
supply mechanism 14 comprises a housing hole 101, a pump case 102,
and a pump vane 103.
[0044] That is, in the oil supply mechanism 14, as illustrated in
FIGS. 1, 3, and 4, the housing hole 101 is formed in the bottom of
the rotation shaft 33 and has an opening in the lower end. On the
other hand, a through hole 104 is formed in the top of the rotation
shaft 33. The through hole 104 has an opening in the upper end and
is communicated with the housing hole 101. At the middle of the
rotation shaft 33, a horizontal hole 105 is formed that passes
through in the redial direction to be communicated with the housing
hole 101. The oil supply hole 100 includes the housing hole 101,
the through hole 104, and the horizontal hole 105. The horizontal
hole 105 is provided correspondingly to the upper bearing 62a, the
first annular piston 43, the second annular piston 53, and the
lower bearing 63a.
[0045] The pump case 102 is a cylindrical pipe in the lower end of
which is formed a lubricant oil inlet 106 having the inner diameter
as a small diameter. The pump case 102 has an opening in the upper
end and is fitted in the housing hole 101. The pump vane 103 is of
a plate-like shape and is housed in the housing hole 101 and the
pump case 102. The pump vane 103 is provided with a large width
portion 107 at the center in the longitudinal direction. The large
width portion 107 is locked by the upper inner surface of the pump
case 102.
[0046] The housing hole 101 formed in the rotation shaft 33
comprises a housing hole main body 101a, a stepped portion 101b,
and an attachment hole 101c. The attachment hole 101c is located
below the housing hole main body 101a with the stepped portion 101b
therebetween and has a diameter slightly larger than that of the
housing hole main body 101a. The upper end portion of the pump case
102 is fitted in the attachment hole 101c of the housing hole 101
and is in contact with the stepped portion 101b, and thereby the
pump case 102 is positioned. The pump case 102 is press-fitted into
the attachment hole 101c to be fixed to the rotation shaft 33. In
this case, preferably, a press fitting margin is set to 0 to 0.06
mm between the pump case 102 and the attachment hole 101c. It is
also preferable that the inner diameter of the housing hole main
body 101a is substantially the same as that of the pump case
102.
[0047] The pump case 102 is deformable at least in the radial
direction. In the embodiment, the pump case 102 is made of copper,
and thus is a little elastically deformable.
[0048] The pump vane 103 is twisted by a predetermined degree,
180.degree. in the embodiment, in the circumference direction. As
illustrated in FIG. 5, a plate 201 having a predetermined length L
and a predetermined width W is provided with bulges 202a and 202b
formed over a region L1 of a predetermined length at the center in
the longitudinal direction. The bulges 202a and 202b extend from
both sides 203a and 203b of a portion of the plate 201 in the
predetermined width W, respectively, in the width direction by a
predetermined length W1. Between the sides 203a and 203b of the
portion in the predetermined width W and the bulges 202a and 202b,
inclined portions 204a and 204b are formed, respectively. The
inclined portions 204a and 204b are inclined at a predetermined
angle a. The inclined portions 204a and 204b are formed on both
sides of the bulges 202a and 202b, respectively. Further, curved
portions 205 are formed at the four corners of the plate 201. The
curved portions 205 each have a predetermined radius R. The
inclined portions 204a and 204b, and the curved portions 205 may be
formed when press work is performed on the plate 201. The inclined
portions 204a and 204b, and the curved portions 205 may be also
formed by chamfering the corners of the plate 201 or by barrel
polishing after the press work.
[0049] The plate 201 thus formed is twisted 180.degree. to form the
pump vane 103 as illustrated in FIG. 6. At this time, only the
longitudinal end portions of the plate 201 are not twisted to form
flat portions 130a and 103b. The pump vane 103 is longitudinally
symmetrical about the large width portion 107 formed at the center
in the longitudinal direction.
[0050] The twisted pump vane 103 is processed such that the width
of the large width portion 107 is equal to or wider than the inner
diameter of the pump case 102. The large width portion 107 is
press-fitted into the pump case 102, and the pump vane 103 is fixed
by the inner periphery of the pump case 102. Preferably, a press
fitting margin is set to 0 to 0.5 mm between the large width
portion 107 of the pump vane 103 and the pump case 102. The pump
vane 103 is made of an inexpensive elastically deformable material
such as carbon steel for tools (i.e., spring steel) and cold rolled
steel. Therefore, the pump vane 103 is deformable in the twisted
direction. When the pump vane 103 (the large width portion 107) is
press-fitted into the pump case 102, it is deformed in the twisted
direction and is fixed. Preferably, the angle a of the inclined
portions 204a and 204b of the pump vane 103 is set to 10.degree. to
45.degree..
[0051] The pump vane 103 need not necessarily twisted 180.degree.,
and may be twisted by different degrees appropriately set. The
large width portion 107 may be formed by providing a bulge to only
one side of the pump vane 103 in the width direction. The inclined
portions 204a and 204b need not necessarily be straight lines, and
may be curved lines, i.e., arcs that allow the sides 203a and 203b
and the bulges 202a and 202b to smoothly continue,
respectively.
[0052] Upon forming the oil supply mechanism 14 by assembling the
housing hole 101, the pump case 102, and the pump vane 103 thus
obtained, the pump vane 103 is press-fitted into the pump case 102
and is fixed. Then, the pump case 102 to which the pump vane 103 is
fixed is press-fitted into the housing hole 101 of the rotation
shaft 33 and is fixed.
[0053] When the large width portion 107 of the pump vane 103 is
press-fitted into the pump case 102, the pump vane 103 is
elastically deformed in the twisted direction, and the diameter is
reduced. On the other hand, the pump case 102 is elastically
deformed in the radial direction, and the diameter is increased.
This reduces the force required to press-fit the pump vane 103 (the
large width portion 107) into the pump case 102, resulting in less
dust produced by the rubbing of the large width portion 107 and the
pump case 102. Besides, the pump vane 103 is made of a material
such as carbon steel for tools and cold rolled steel and is
elastically deformable. Therefore, the pump vane 103 can be
press-fitted into the pump case 102 with a small hand press, and
the assembly can be easily and reliably performed through press
fitting. When the pump case 102 to which the pump vane 103 is fixed
is press-fitted into the housing hole 101 of the rotation shaft 33,
the elastically deformed pump case 102 with an increased diameter
recovers to the original state. Thus, the pump vane 103 is held
tightly by the pump case 102 and is secured.
[0054] Further, when the large width portion 107 of the pump vane
103 is press-fitted into the pump case 102, the longitudinal end
portion (the corners of the flat portion 103b) of the pump vane 103
housed in the pump case 102 comes in contact with the inner surface
of the pump case 102, and thereby the pump vane 103 is positioned.
When the pump case 102 to which the pump vane 103 is fixed is
press-fitted into the housing hole 101 of the rotation shaft 33,
the end portion of the pump case 102 comes in contact with the
stepped portion 101b, and thereby the pump case 102 is positioned.
At this point, the longitudinal end portion (the corners of the
flat portion 103a) of the pump vane 103 housed in the housing hole
101 is separate from the inner surface of the housing hole 101.
[0055] Accordingly, as illustrated in FIG. 1, when the rotation
shaft 33 rotates in the oil supply mechanism 14, the pump case 102
and the pump vane 103 integrally rotate. With the centrifugal force
of the rotation, lubricant oil retained in the lower part of the
compressor housing 11 can be pumped up. More specifically, the
lubricant oil retained in the compressor housing 11 enters into the
pump case 102 through the lubricant oil inlet 106, and is pumped up
in the housing hole 101 by the rotation of the pump vane 103. The
lubricant oil is then supplied to the upper bearing 62a, the first
annular piston 43, the second annular piston 53, the lower bearing
63a, and the like through the horizontal hole 105 to lubricate
them. After lubricating the components, the lubricant oil enters
into the first operation chamber 44 and the second operation
chamber 54 through a small gap between components that define the
first compressing unit 41 and the second compressing unit 51. The
lubricant oil lubricates the sliding portions of the respective
components and provides pressure sealing to the small gap.
Thereafter, the lubricant oil is discharged.
[0056] In the following, the operation of the rotary compressor of
the embodiment will be described. When the rotary compressor is
activated, refrigerant flows from the low pressure side of the
refrigeration cycle into the accumulator 81 through the system
connecting pipe 83. The refrigerant is separated into liquid
refrigerant and gas refrigerant. The liquid refrigerant is
accumulated in the lower part of the accumulator 81, while the gas
refrigerant is accumulated in the upper part.
[0057] In the compressor housing 11, the rotation shaft 33 is
driven by the motor 13 and rotates. Through the first and second
eccentric portions 64 and 65, the first and second annular pistons
43 and 53 revolve and rotate. As the first and second annular
pistons 43 and 53 revolve while rotating in the first cylinder 42
and the second cylinder 52, the volume of the first inlet chamber
44a and the second inlet chamber 54a increases. Accordingly, the
gas refrigerant in the accumulator 81 is sucked into the first
inlet chamber 44a and the second inlet chamber 54a via the first
inlet pipe 84, the second inlet pipe 85, the first inlet 48, and
the second inlet (not illustrated).
[0058] When the first and second annular pistons 43 and 53 make one
revolution, the first inlet chamber 44a and the second inlet
chamber 54a are shut off from the first inlet 48 and the second
inlet (not illustrated). The first inlet chamber 44a and the second
inlet chamber 54a switch to the first compression chamber 44b and
the second compression chamber 54b, respectively, to compress the
gas refrigerant.
[0059] When the pressure of the compressed refrigerant in the first
compression chamber 44b and the second compression chamber 54b
reaches that of the upper muffler chamber 67 and the lower muffler
chamber 71 located downstream of the first outlet valve 69 and the
second outlet valve 73 of the first outlet 68 and the second outlet
72, the first outlet valve 69 and the second outlet valve 73 are
opened. The compressed refrigerant is discharged through the first
outlet 68 and the second outlet 72 into the upper muffler chamber
67 and the lower muffler chamber 71. The upper muffler chamber 67
and the lower muffler chamber 71 reduce the pressure pulsation of
the refrigerant that causes noise. The refrigerant is then
discharged into the compressor housing 11 as high pressure
refrigerant.
[0060] After that, the high pressure refrigerant flows through the
core cutout (not illustrated) of the starter 31 of the motor 13,
and a gap between the core and a winding. The high pressure
refrigerant is sent to the upper part of the motor 13, and is
discharged to the high pressure side of the refrigeration cycle
through the outlet pipe 86.
[0061] At this time, the lubricant oil retained in the lower part
of the compressor housing 11 is pumped up by the oil supply
mechanism 14 to lubricate the upper bearing 62a, the first annular
piston 43, the second annular piston 53, the lower bearing 63a, and
the like. More specifically, the pump case 102 and the pump vane
103 rotate with the rotation shaft 33, the lubricant oil is pumped
up by the centrifugal force in the housing hole 101, and is
supplied to the upper bearing 62a, the first annular piston 43, the
second annular piston 53, the lower bearing 63a, and the like
through the horizontal hole 105 to lubricate them. After
lubricating the components, the lubricant oil is sent back to the
lower part of the compressor housing 11.
[0062] As described above, according to the embodiment, the rotary
compressor comprises the compressing unit 12, the motor 13, and the
oil supply mechanism 14. The compressing unit 12 compresses
refrigerant sucked in the lower part of the compressor housing 11.
The motor 13 is located above the compressor housing 11 and drives
the compressing unit 12 through the rotation shaft 33. The oil
supply mechanism 14 supplies lubricant oil retained in the lower
part of the compressor housing 11 to the sliding portion of the
compressing unit 12 through the oil supply hole 100 of the rotation
shaft 33. The oil supply mechanism 14 comprises the housing hole
101, the pump case 102, and the pump vane 103. The housing hole 101
formed in the bottom of the rotation shaft 33 has an opening in the
lower end, and is communicated with the oil supply hole 100. The
pump case 102 is provided with the lubricant oil inlet 106 in the
lower end and an opening in the upper end, and is fitted in the
housing hole 101. The pump vane 103 is of a plate-like shape and is
housed in the housing hole 101 and the pump case 102. The pump vane
103 is provided with the large width portion 107 at the
longitudinal center. The large width portion 107 is locked by the
upper inner surface of the pump case 102.
[0063] In other words, the pump vane 103 is locked by the upper
inner surface of the pump case 102 through the large width portion.
The pump case 102 is fitted in the housing hole 101 of the rotation
shaft 33. With this, the pump vane 103 is placed in the oil supply
hole 100 of the rotation shaft 33. Accordingly, when the pump case
102 is fitted in the housing hole 101, the pump vane 103 does not
touch the housing hole 101. This prevents the deformation of the
pump vane 103 and improves the assembly efficiency.
[0064] Moreover, according to the embodiment, the longitudinal end
portion of the pump vane 103 housed in the pump case 102 comes in
contact with the inner surface of the pump case 102, and thereby
the pump vane 103 is positioned. In this manner, the pump vane 103
is positioned at a predetermined location relative to the pump case
102. Accordingly, the pump vane 103 is easily positioned at a
predetermined location in the housing hole 101 by only fitting the
pump case 102 in the housing hole 101. This improves the assembly
efficiency.
[0065] On the other hand, the longitudinal end portion of the pump
vane 103 housed in the housing hole 101 is separate from the inner
surface of the housing hole 101. That is, the pump vane 103 is in
contact with the pump case 102 at one end to be positioned, and is
separate from the housing hole 101 at the other end. Therefore,
excessive stress is not placed on the pump vane 103. Thus, it is
possible to prevent the deformation or damage of the pump vane 103
and increase the durability.
[0066] Further, according to the embodiment, the housing hole 101
comprises the housing hole main body 101a, the stepped portion
101b, and the attachment hole 101c having a larger diameter. The
upper end portion of the pump case 102 is fitted in the attachment
hole 101c and is in contact with the stepped portion 101b, and
thereby the pump case 102 is positioned. In this manner, by
positioning the pump case 102 using the stepped portion 101b of the
housing hole 101, the pump vane 103 is positioned with respect to
the housing hole 101. This eliminates the need to directly position
the pump vane 103. Thus, it is possible to prevent the deformation
or damage of the pump vane 103 as well as to improve the assembly
efficiency.
[0067] Further, according to the embodiment, the bulges 202a and
202b are formed at the longitudinal center of the pump vane 103 to
extend outward. The bulges 202a and 202b form the large width
portion 107 having a width equal to or wider than the inner
diameter of the pump case 102. Since the large width portion 107 is
formed in such a simple manner, the manufacturing cost can be
reduced.
[0068] Besides, the inclined portions 204a and 204b are formed
between the bulges 202a and 202b and the sides 203a and 203b of the
pump vane 103, respectively. When the pump vane 103 is fitted into
the pump case 102, the large width portion (the bulges 202a and
202b) is fitted from the sides 203a and 203b through the inclined
portions 204a and 204b. Thus, the pump vane 103 can be smoothly
fitted into the pump case 102. This reduces dust produced by
rubbing in the pump case 102 and the pump vane 103 as well as
preventing damage to them.
[0069] The pump vane 103 is twisted by a predetermined degree in
the circumference direction and is made of a material that allows
the pump vane 103 to be elastically deformable in the twisted
direction. Accordingly, when fitted into the pump case 102, the
pump vane 103 is elastically deformed in the twisted direction.
Thus, the pump vane 103 can be smoothly fitted into the pump case
102.
[0070] Further, according to the embodiment, the pump case 102 is
deformable at least in the radial direction. Accordingly, when the
pump vane 103 is fitted into the pump case 102, the pump case 102
is deformed so that the pump vane 103 can be smoothly fitted into
the pump case 102. After that, when the pump case 102 is fitted in
the housing hole 101, the elastically deformed pump case 102
recovers to the original state. Thus, the pump vane 103 can be
fixed securely to the pump case 102.
[0071] Furthermore, according to the embodiment, the large width
portion 107, i.e., the bulges 202a and 202b, the sides 203a and
203b, the inclined portions 204a and 204b, and the curved portions
205, is formed such that the pump vane 103 is point-symmetrical
about the center. Therefore, the direction in which the pump vane
103 is fitted into the pump case 102 is not restricted, which
improves the assembly efficiency.
[0072] All examples and conditional language recited herein are
intended for pedagogical purposes to aid the reader in
understanding the invention and the concepts contributed by the
inventor to furthering the art, and are to be construed as being
without limitation to such specifically recited examples and
conditions, nor does the organization of such examples in the
specification relate to a showing of the superiority and
inferiority of the invention. Although the embodiment(s) of the
present inventions have been described in detail, it should be
understood that the various changes, substitutions, and alterations
could be made hereto without departing from the spirit and scope of
the invention.
* * * * *