U.S. patent application number 11/720267 was filed with the patent office on 2009-05-28 for hermetic compressor.
This patent application is currently assigned to MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.. Invention is credited to Takashi Kakiuchi, Kiwamu Watanabe.
Application Number | 20090136369 11/720267 |
Document ID | / |
Family ID | 37719848 |
Filed Date | 2009-05-28 |
United States Patent
Application |
20090136369 |
Kind Code |
A1 |
Kakiuchi; Takashi ; et
al. |
May 28, 2009 |
HERMETIC COMPRESSOR
Abstract
This hermetic compressor includes a regulation mechanism, which
is arranged between a lower washer and an upper end face of a
bearing, for regulating a movable distance in a thrust direction of
the lower washer so that the movable distance can be shorter than
clearance between an inner diameter of the lower washer and an
outer diameter of a main shaft portion. It is possible to prevent
the inner diameter of the lower washer from coming into contact
with the outer diameter of the main shaft portion by this
regulation mechanism.
Inventors: |
Kakiuchi; Takashi;
(Kanagawa, JP) ; Watanabe; Kiwamu; (Kanagawa,
JP) |
Correspondence
Address: |
PEARNE & GORDON LLP
1801 EAST 9TH STREET, SUITE 1200
CLEVELAND
OH
44114-3108
US
|
Assignee: |
MATSUSHITA ELECTRIC INDUSTRIAL CO.,
LTD.
Osaka
JP
|
Family ID: |
37719848 |
Appl. No.: |
11/720267 |
Filed: |
November 21, 2006 |
PCT Filed: |
November 21, 2006 |
PCT NO: |
PCT/JP2006/323631 |
371 Date: |
May 25, 2007 |
Current U.S.
Class: |
417/410.1 ;
417/902 |
Current CPC
Class: |
F16C 35/06 20130101;
F16C 19/10 20130101; F04B 39/0246 20130101 |
Class at
Publication: |
417/410.1 ;
417/902 |
International
Class: |
F04B 35/04 20060101
F04B035/04 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 22, 2005 |
JP |
2005-336560 |
Sep 1, 2006 |
JP |
2006-237235 |
Claims
1. A hermetic compressor comprising: an electrically driving
element having a stator and a rotor, the electrically driving
element being accommodated in a hermetic container; and a
compression element driven by the electrically driving element, the
compression element being accommodated in the hermetic container,
the compression element comprising: a shaft; a cylinder block
forming a compression chamber; a bearing for supporting the shaft,
arranged in the cylinder block; a piston reciprocated in the
compression chamber; a connecting portion for connecting the piston
with an eccentric shaft portion; and a thrust ball bearing, the
thrust ball bearing comprising: a plurality of balls; a holder
portion for holding the balls; an upper washer arranged above the
balls; and a lower washer arranged below the balls, the hermetic
compressor further comprising a regulation mechanism for regulating
the lower washer so that a movable distance in the thrust direction
of the lower washer can be shorter than clearance formed between an
inner diameter of the lower washer and an outer diameter of the
main shaft portion.
2. The hermetic compressor of claim 1, wherein the shaft comprises
a main shaft portion and an eccentric shaft portion formed through
a flange portion; and wherein the thrust ball bearing is arranged
between the flange portion and an upper end face of the
bearing.
3. The hermetic compressor of claim 2, wherein the regulation
mechanism comprises a first cylindrical wall, which is arranged in
the cylinder block or the bearing, surrounding the outside of the
lower washer; and wherein clearance between an outer diameter of
the lower washer and an inner diameter of the first cylindrical
wall is smaller than clearance between an inner diameter of the
lower washer and an outer diameter of the main shaft portion.
4. The hermetic compressor of claim 2, wherein the regulation
mechanism comprises a first recess portion and a first protruding
portion which are idly engaged with each other and respectively
arranged on the lower washer and the upper end face of the bearing;
and wherein clearance in the thrust direction between the first
recess portion and the first protruding portion is smaller than
clearance between an inner diameter of the lower washer and an
outer diameter of the main shaft portion.
5. The hermetic compressor of claim 2, wherein the regulation
mechanism comprises a first bent portion on an outer circumference
of the lower washer; and wherein clearance in the thrust direction
between an inner circumferential face of the first bent portion and
an outer diameter of the bearing is smaller than clearance between
an inner diameter of the lower washer and an outer diameter of the
main shaft portion.
6. The hermetic compressor of claim 2, wherein the regulation
mechanism comprises a first annular protruding portion arranged
inside an upper end face of the bearing; and wherein the first
annular protruding portion and an inner circumference of the lower
washer are idly engaged with each other.
7. The hermetic compressor of claim 1, wherein the shaft comprises
a main shaft portion to which the eccentric shaft portion and the
rotor are fixed; and wherein the thrust ball bearing is arranged
between an upper end face of the bearing and the rotor fixed to the
main shaft portion.
8. The hermetic compressor of claim 7, wherein a second cylindrical
wall for surrounding the outside of the lower washer is provided in
an upper portion of the bearing; and wherein the regulation
mechanism is composed in such a manner that clearance between an
outer diameter of the lower washer and an inner diameter of the
second cylindrical wall is smaller than clearance between an inner
diameter of the lower washer and an outer diameter of the main
shaft portion.
9. The hermetic compressor of claim 7, wherein the regulation
mechanism comprises a second recess portion and a second protruding
portion which are idly engaged with each other and respectively
arranged on the lower washer and the upper end face of the bearing;
and wherein clearance in the thrust direction between the second
recess portion and the second protruding portion is smaller than
clearance between an inner diameter of the lower washer and an
outer diameter of the main shaft portion.
10. The hermetic compressor of claim 7, wherein the regulation
mechanism comprises a second bent portion on an outer circumference
of the lower washer; and wherein clearance in the thrust direction
between an inner circumferential face of the second bent portion
and an outer diameter of the bearing is smaller than clearance
between an inner diameter of the lower washer and an outer diameter
of the main shaft portion.
11. The hermetic compressor of claim 7, wherein the regulation
mechanism comprises a second annular protruding portion arranged
inside an upper end face of the bearing; and wherein the second
annular protruding portion and an inner circumference of the lower
washer are idly engaged with each other.
Description
TECHNICAL FIELD
[0001] The present invention relates to a hermetic compressor
mainly used for a refrigerator for domestic use.
BACKGROUND ART
[0002] In a conventional hermetic compressor in which a thrust ball
bearing is employed for enhancing the efficiency, washers arranged
on the upper and lower sides of the thrust ball bearing can be
freely rotated round the shaft and the bearing. This prior art is
disclosed, for example, in the official gazette of Japanese Patent
Unexamined Publication No. 61-53474.
[0003] Referring to the drawings, the above conventional hermetic
compressor will be explained below.
[0004] FIG. 18 is a longitudinal sectional view of the conventional
hermetic compressor and FIG. 19 is an enlarged sectional view
showing a primary portion of the conventional hermetic
compressor.
[0005] In FIGS. 18 and 19, refrigerant 3002 is charged into
hermetic container 3001. Further, refrigerating machine oil 3003 is
stored in hermetic container 3001.
[0006] Electrically driving element 3011 includes: stator 3012
connected to an external electric power source (not shown): and
rotor 3013 arranged inside stator 3012, forming a predetermined gap
between rotor 3013 and stator 3012.
[0007] Compression element 3021 includes: shaft 3022; cylinder
block 3023; bearing 3024; piston 3025 reciprocating in compression
chamber 3023a; connecting portion 3026; and thrust ball bearing
3031. Shaft 3022 includes: main shaft portion 3022a; and eccentric
shaft portion 3022c. Cylinder block 3023 is fixed under stator 3012
and forms compression chamber 3023a. Bearing 3024 supports shaft
3022 provided in cylinder block 3023. Piston 3025 is reciprocated
in compression chamber 3023a. Connecting portion 3026 connects
piston 3025 with eccentric shaft portion 3022c. Thrust ball bearing
3031 is arranged between rotor 3013 and an upper end face of
bearing 3024. Compression element 3021 composes a reciprocating
type compression mechanism.
[0008] Thrust ball bearing 3031 includes: a plurality of balls
3032; holder portion 3033 to hold balls 3032; upper washer 3034
arranged above balls 3032; and lower washer 3035 arranged below
balls 3032.
[0009] Operation of the hermetic compressor composed as described
above will be explained as follows.
[0010] When stator 3012 is energized by an external electric power
source, rotor 3013 is rotated together with shaft 3022. Due to the
foregoing, an eccentric motion is conducted by eccentric shaft
portion 3022c. Therefore, eccentric shaft portion 3022c
reciprocates piston 3025 through connecting portion 3026 in
compression chamber 3023a. Accordingly, a predetermined compressive
motion to compress suction gas is conducted.
[0011] Thrust ball bearing 3031 supports a vertical load generated
by the dead weights of rotor 3013 and shaft 3022. Therefore, it is
possible to reduce a frictional force generated between rotor 3013
and bearing 3024. Accordingly, an intensity of electric power to be
inputted into the hermetic compressor can be decreased and the
efficiency can be enhanced.
[0012] However, in the above conventional structure, in order to
make it easy to assemble the components, thrust ball bearing 3031
is only put on an upper end face of bearing 3024, that is, thrust
ball bearing 3031 is arranged without being fixed. Accordingly,
there is a possibility that lower washer 3035 is arranged being
shifted at the time of assembling. Further, there is a possibility
that lower washer 3035 is shifted by a shock while the device is
being conveyed and an inner diameter of lower washer 3035 comes
into contact with an outer diameter of main shaft portion 3022
which is being rotated.
[0013] Concerning lower washer 3035, since a lower face of lower
washer 3035 is closely contacted with an upper end face of bearing
3024 through viscosity of refrigerating machine oil 3003, lower
washer 3035 is not rotated together with balls 3032 and holder
portion 3033. Therefore, when an inner diameter of lower washer
3035 comes into contact with an outer diameter of main shaft
portion 3022a which is rotating, abrasion powder is generated. The
thus generated abrasion powder spreads to each sliding portion of
the hermetic compressor and causes abrasion.
DISCLOSURE OF THE INVENTION
[0014] A hermetic compressor comprises:
[0015] an electrically driving element having stator and a rotor,
the electrically driving element being accommodated in a hermetic
container; and
[0016] a compression element driven by the electrically driving
element, the compression element being accommodated in the hermetic
container,
[0017] the compression element comprising: [0018] a shaft; [0019] a
cylinder block forming a compression chamber; [0020] a bearing for
supporting the shaft, arranged in the cylinder block; [0021] a
piston reciprocated in the compression chamber; [0022] a connecting
portion for connecting the piston with an eccentric shaft portion;
and [0023] a thrust ball bearing,
[0024] the thrust ball bearing comprising: [0025] a plurality of
balls; [0026] a holder portion for holding the balls; [0027] an
upper washer arranged above the balls; and [0028] a lower washer
arranged below the balls,
[0029] the hermetic compressor further comprising a regulation
mechanism for regulating the lower washer so that a movable
distance in the thrust direction of the lower washer can be shorter
than clearance formed between an inner diameter of the lower washer
and an outer diameter of the main shaft portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 is a longitudinal sectional view of a hermetic
compressor of Embodiment 1 of the present invention.
[0031] FIG. 2 is an enlarged sectional view showing a primary
portion of the hermetic compressor of Embodiment 1 of the present
invention.
[0032] FIG. 3 is a longitudinal sectional view of a hermetic
compressor of Embodiment 2 of the present invention.
[0033] FIG. 4 is an enlarged sectional view showing a primary
portion of the hermetic compressor of Embodiment 2 of the present
invention.
[0034] FIG. 5 is a longitudinal sectional view of a hermetic
compressor of Embodiment 3 of the present invention.
[0035] FIG. 6 is an enlarged sectional view showing a primary
portion of the hermetic compressor of Embodiment 3 of the present
invention.
[0036] FIG. 7 is a view showing an example of Embodiment 3 of the
present invention.
[0037] FIG. 8 is a longitudinal sectional view of a hermetic
compressor of Embodiment 4 of the present invention.
[0038] FIG. 9 is an enlarged sectional view showing a primary
portion of the hermetic compressor of Embodiment 4 of the present
invention.
[0039] FIG. 10 is a longitudinal sectional view of a hermetic
compressor of Embodiment 5 of the present invention.
[0040] FIG. 11 is an enlarged sectional view showing a primary
portion of the hermetic compressor of Embodiment 5 of the present
invention.
[0041] FIG. 12 is a longitudinal sectional view of a hermetic
compressor of Embodiment 6 of the present invention.
[0042] FIG. 13 is an enlarged sectional view showing a primary
portion of the hermetic compressor of Embodiment 6 of the present
invention.
[0043] FIG. 14 is a longitudinal sectional view of a hermetic
compressor of Embodiment 7 of the present invention.
[0044] FIG. 15 is an enlarged sectional view showing a primary
portion of the hermetic compressor of Embodiment 7 of the present
invention.
[0045] FIG. 16 is a longitudinal sectional view of a hermetic
compressor of Embodiment 8 of the present invention.
[0046] FIG. 17 is an enlarged sectional view showing a primary
portion of the hermetic compressor of Embodiment 8 of the present
invention.
[0047] FIG. 18 is a longitudinal sectional view showing a
conventional hermetic compressor.
[0048] FIG. 19 is an enlarged sectional view showing a primary
portion of the conventional hermetic compressor.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0049] The present invention has been accomplished to solve the
above problems. An object of the present invention is to provide a
highly reliable hermetic compressor.
[0050] In order to solve the above conventional problems, a
hermetic compressor of the present invention includes a regulation
means, which is arranged between a lower washer and an upper end
face of a bearing, for regulating the lower washer so that a
movable distance in the thrust direction of the lower washer can be
shorter than clearance between an inner diameter of the lower
washer and an outer diameter of a main shaft portion. Due to the
above structure, the inner diameter of the lower washer can be
prevented from coming into contact with the outer diameter of the
main shaft portion. Therefore, the generation of abrasion powder
can be prevented.
[0051] In the hermetic compressor of the present invention, the
generation of abrasion powder can be prevented. Therefore, it is
possible to provide a highly reliable hermetic compressor.
[0052] Referring to the drawings, embodiments of the present
invention will be explained below. In this connection, it should be
noted that the present invention is not limited to this specific
embodiment.
Embodiment 1
[0053] FIG. 1 is a longitudinal sectional view of a hermetic
compressor of Embodiment 1 of the present invention. FIG. 2 is an
enlarged sectional view showing a primary portion of the hermetic
compressor of Embodiment 1 of the present invention.
[0054] In FIGS. 1 and 2, refrigerant 1102 is charged into hermetic
container 1101. Further, refrigerating machine oil 1103 is stored
in hermetic container 1101. In this case, refrigerant 1102 is R600a
which is a hydrocarbon refrigerant. Refrigerating machine oil 1103
is an oil, which is compatible with refrigerant 1102, such as
synthetic fluid, mineral oil or polyol ester oil.
[0055] Electric driving element 1111 includes: stator 1112
connected to an external electric power source (not shown); and
rotor 1113 arranged, forming a predetermined gap between rotor 1113
and stator 1112.
[0056] Compression element 1121 includes: shaft 1122; cylinder
block 1123; bearing 1124; piston 1125; connecting portion 1126; and
thrust ball bearing 1131. Shaft 1122 includes: main shaft portion
1122a, the outer diameter of which is d; and eccentric shaft
portion 1122c formed out of main shaft portion 1122a through flange
portion 1122b. Cylinder block 1123 composes compression chamber
1123a. Bearing 1124 supports shaft 1122 provided in cylinder block
1123. Piston 1125 reciprocates in compression chamber 1123a.
Connecting portion 1126 connects piston 1125 with eccentric shaft
portion 1122c. Thrust ball bearing 1131 is arranged between flange
portion 1122b and an upper end face of bearing 1124. Compression
element 1121 composes a reciprocating type compression
mechanism.
[0057] Rotor 1113 is engaged with main shaft portion 1122a of the
shaft. Stator 1112 is arranged and fixed in a lower portion of
cylinder block 1123.
[0058] Thrust ball bearing 1131 includes: a plurality of balls
1132; holder portion 1133 for holding balls 1132; upper washer 1134
arranged above balls 1132; and lower washer 1135, the outer
diameter of which is b and the inner diameter of which is C,
arranged below balls 1132. In cylinder block 1123, at a height in
which lower washer 1135 is arranged, first cylindrical wall 1141,
the inner diameter of which is A, surrounding the outside of lower
washer 1135, is arranged. It is composed so that clearance (A-b)/2
between outer diameter b of lower washer 1135 and inner diameter A
of first cylinder wall 1141 can be smaller than clearance (C-d)/2
between inner diameter C of lower washer 1135 and outer diameter d
of main shaft portion 1122a.
[0059] Operation and action of the hermetic compressor composed as
described above will be explained below.
[0060] When stator 1112 is energized by an external electric power
source (not shown), rotor 1113 is rotated together with shaft 1122.
Due to the foregoing, an eccentric motion is conducted by eccentric
shaft portion 1122c. Therefore, eccentric shaft portion 1122c
reciprocates piston 1125 through connecting portion 1126 in
compression chamber 1123a. Accordingly, a predetermined compressive
motion to compress suction gas is conducted.
[0061] At this time, balls 1132 of thrust ball bearing 1131 support
a vertical load generated by the dead weights of rotor 1113 and
shaft 1122. An upper surface of upper washer 1134 is closely
contacted with a lower surface of flange portion 1122b of shaft
1122 through viscosity of refrigerating machine oil 1103.
Therefore, when shaft 1122 is rotated, upper washer 1134 is rotated
synchronously with shaft 1122. On the other hand, a lower surface
of lower washer 1135 is also closely contacted with an upper end
portion of bearing 1124 through viscosity of refrigerating machine
oil 1103. Therefore, lower washer 1135 is not rotated. Since
slippage is generated between rotating balls 1132 and lower washer
1135, balls 1132 and holder portion 1133 are rotated being delayed
without following a rotation of shaft 1122. In general, the
coefficient of rolling friction is 10 to 20 times as low as the
coefficient of sliding friction. Further, no metal contact is
caused in the rolling bearing. Therefore, it is possible to conduct
a stable motion by the rolling bearing.
[0062] In this structure, clearance (A-b)/2 between outer diameter
b of lower washer 1135 and inner diameter A of first cylinder wall
1141 is smaller than clearance (C-d)/2 between inner diameter C of
lower washer 1135 and outer diameter d of main shaft portion 1122a.
Accordingly, before lower washer 1135 comes into contact with main
shaft portion 1122a, an outer diameter of lower washer 1135 and an
inner diameter of cylindrical wall 1141 are contacted with each
other. That is, by first cylindrical wall 1141 surrounding the
outside of lower washer 1135, the inner diameter of lower washer
1135 is arranged at a position where the inner diameter of lower
washer 1135 does not come into contact with the outer diameter of
main shaft portion 1122a.
[0063] When first cylindrical wall 1141 surrounding the outside of
lower washer 1135 is provided in cylinder block 1123 or bearing
1124 as described above, a regulation mechanism is formed.
[0064] Consequently, according to the present embodiment, the inner
diameter of lower washer 1135 can be prevented from coming into
contact with the outer diameter of main shaft portion 1122a by this
regulation mechanism. Accordingly, there is no possibility that
lower washer 1135 damages main shaft portion 1122a and generates
abrasion powder. Therefore, it is possible to realize a highly
reliable hermetic compressor.
[0065] Since first cylindrical wall 1141 can be manufactured
simultaneously when cylinder block 1123 or bearing 1124 is
machined, it is unnecessary to add a new component. Therefore, the
productivity can be enhanced.
[0066] Further, since thrust ball bearing 1131 can be incorporated
into the device only when it is accommodated in first cylindrical
wall 1141 with shaft 1122 being inserted into the thrust ball
bearing at the time of assembling, it is unnecessary to use a
special assembling method such as a method of press-fitting lower
washer 1135. Accordingly, the working property can be enhanced at
the time of assembling.
[0067] In this connection, in the present embodiment, first
cylindrical wall 1141 is integrated with cylinder block 1123 into
one body. However, of course, it is possible to provide the same
effect even when first cylindrical wall 1141 is integrated with
bearing 1124 into one body.
Embodiment 2
[0068] FIG. 3 is a longitudinal sectional view of a hermetic
compressor of Embodiment 2 of the present invention. FIG. 4 is an
enlarged sectional view showing a primary portion of the hermetic
compressor of Embodiment 2 of the present invention.
[0069] Like reference characters are used to indicate like parts in
Embodiments 1 and 2.
[0070] In FIGS. 3 and 4, refrigerant 1102 is charged into hermetic
container 1101. Further, refrigerating machine oil 1103 is stored
in hermetic container 1101. In this case, refrigerant 1102 is R600a
which is a hydrocarbon refrigerant. Refrigerating machine oil 1103
is an oil, which is compatible with refrigerant 1102, such as
synthetic fluid, mineral oil or polyol ester oil.
[0071] Electric driving element 1111 includes: stator 1112
connected to an external electric power source (not shown); and
rotor 1113 arranged, forming a predetermined gap between rotor 1113
and stator 1112.
[0072] Compression element 1221 includes: shaft 1122; cylinder
block 1123; bearing 1224; piston 1125; connecting portion 1126; and
thrust ball bearing 1231. Shaft 1122 includes: main shaft portion
1122a, the outer diameter of which is d; and eccentric shaft
portion 1122c formed out of main shaft portion 1122a through flange
portion 1122b. Cylinder block 1123 is fixed in a portion above
stator 1112 and composes compression chamber 1123a. Bearing 1224
supports shaft 1122 provided in cylinder block 1123. Piston 1125
reciprocates in compression chamber 1123a. Connecting portion 1126
connects piston 1125 with eccentrics haft portion 1122c. Thrust
ball bearing 1231 is arranged between flange portion 1122b and an
upper end face of bearing 1224. Compression element 1221 composes a
reciprocating type compression mechanism.
[0073] Rotor 1113 is engaged with main shaft portion 1122a of the
shaft. Stator 1112 is arranged and fixed in a lower portion of
cylinder block 1123.
[0074] Thrust ball bearing 1231 includes: a plurality of balls
1232; holder portion 1233 for holding balls 1232; upper washer 1234
arranged above balls 1232; and lower washer 1235, the outer
diameter of which is b and the inner diameter of which is C,
arranged below the balls 1232. On lower washer 1235, first recess
portion 1241 is provided. On an upper end face of bearing 1224,
first protruding portion 1242 is provided. First recess portion
1241 and first protruding portion 1242 are idly engaged with each
other. It is composed so that Clearance (E-f)/2 in the thrust
direction between width E in the thrust direction of first recess
portion 1241 and width f in the thrust direction of first
protruding portion 1242 can be smaller than clearance (C-d)/2
between inner diameter C of lower washer 1235 and outer diameter d
of main shaft portion 1122a.
[0075] Operation and action of the hermetic compressor composed as
described above will be explained below.
[0076] When stator 1112 is energized by an external electric power
source (not shown), rotor 1113 is rotated together with shaft 1122.
Due to the foregoing, an eccentric motion is conducted by eccentric
shaft portion 1122c. Therefore, eccentric shaft portion 1122c
reciprocates piston 1125 through connecting portion 1126 in
compression chamber 1123a. Accordingly, a predetermined compressive
motion to compress suction gas is conducted.
[0077] At this time, balls 1232 of thrust ball bearing 1231 support
a vertical load generated by the dead weights of rotor 1113 and
shaft 1122. An upper surface of upper washer 1234 is closely
contacted with a lower surface of flange portion 1122b of shaft
1122 through viscosity of refrigerating machine oil 1103.
Therefore, when shaft 1122 is rotated, upper washer 1234 is rotated
synchronously with shaft 1122. On the other hand, a lower surface
of lower washer 1235 is also closely contacted with an upper end
portion of bearing 1224 through viscosity of refrigerating machine
oil 1103. Therefore, lower washer 1235 is not rotated. Slippage is
generated between rotating balls 1232 and lower washer 1235.
Therefore, balls 1232 and holder portion 1233 are rotated being
delayed without following a rotation of shaft 1122. In general, the
coefficient of rolling friction is 10 to 20 times as low as the
coefficient of sliding friction. Further, no metal contact is
caused in the rolling bearing. Therefore, it is possible to conduct
a stable motion by the rolling bearing.
[0078] Clearance (E-f)/2 in the thrust direction between width E in
the thrust direction of first recess portion 1241 and width f in
the thrust direction of first protruding portion 1242 is smaller
than clearance (C-d)/2 between inner diameter C of lower washer
1235 and outer diameter d of main shaft portion 1122a. Therefore,
before lower washer 1235 comes into contact with main shaft portion
1122a, an end face of first recess portion 1241 and an end face of
first protruding portion 1242 come into contact with each other.
That is, by first recess portion 1241 and first protruding portion
1242, the inner diameter of lower washer 1235 is surely arranged at
a position where it can not be contacted with the outer diameter of
rotating main shaft portion 1122a. Therefore, according to the
present embodiment, there is no possibility that the inner diameter
of lower washer 1235 comes into contact with the outer diameter of
main shaft portion 1122a.
[0079] As described above, on lower washer 1235, first recess
portion 1241 is provided. On the upper end face of bearing 1224,
first protruding portion 1242 is provided. First recess portion
1241 and first protruding portion 1242 are idly engaged with each
other. In this way, a regulation mechanism is formed.
[0080] According to the present embodiment, by this regulation
mechanism, the inner diameter of lower washer 1235 can be prevented
from coming into contact with the outer diameter of main shaft
portion 1122a. Accordingly, there is no possibility that lower
washer 1235 damages main shaft portion 1122a and generates abrasion
powder. Therefore, it is possible to realize a highly reliable
hermetic compressor.
[0081] First recess portion 1241 can be formed, for example,
simultaneously when lower washer 1235 is formed by means of press
forming. First protruding portion 1242 can be formed, for example,
simultaneously when bearing 1242 is molded by means of die-cast
molding. Therefore, it is unnecessary to add a manufacturing step.
Accordingly, it is possible to enhance the productivity of
producing a hermetic compressor.
[0082] Since thrust ball bearing 1231 can be incorporated into the
device only when shaft 1122 is inserted into the thrust ball
bearing and first recess portion 1241 and first protruding portion
1242 are idly engaged with each other at the time of assembling, it
is unnecessary to use a special assembling method such as a method
of press-fitting lower washer 1135. Accordingly, the working
property of assembling can be enhanced.
[0083] In the present embodiment, first recess portion 1241 is a
hollow portion which does not penetrate lower washer 1235. However,
as long as first protruding portion 1242 does not exceed the wall
thickness of lower washer 1235 and first recess portion 1241 is out
of the rotary locus of balls 1232 controlled by holder portion
1233, of course, first recess portion 1241 can provide the same
operational effect as that of a hole penetrating lower washer
1235.
[0084] In the present embodiment, first recess portion 1241 is a
hollow portion not penetrating lower washer 1235. However, as long
as first protruding portion 1242 is out of the rotary locus of
balls 1232 controlled by holder portion 1233 and first protruding
portion 1242 is arranged in a range in which first protruding
portion 1242 can not obstruct rotating balls 1232, of course, the
same operational effect can be provided even when first recess
portion 1241 is a hole penetrating lower washer 1235 and first
protruding portion 1242 exceeds the wall thickness of lower washer
1235.
Embodiment 3
[0085] FIG. 5 is a longitudinal sectional view of a hermetic
compressor of Embodiment 3 of the present invention. FIG. 6 is an
enlarged sectional view showing a primary portion of the hermetic
compressor of Embodiment 3 of the present invention. FIG. 7 is a
view showing an example of Embodiment 3 of the present
invention.
[0086] Like reference characters are used to indicate like parts in
Embodiments 1 and 3.
[0087] In FIGS. 5 and 6, refrigerant 1102 is charged into hermetic
container 1101. Further, refrigerating machine oil 1103 is stored
in hermetic container 1101. In this case, refrigerant 1102 is R600a
which is a hydrocarbon refrigerant. Refrigerating machine oil 1103
is an oil, which is compatible with refrigerant 1102, such as
synthetic fluid, mineral oil or polyol ester oil.
[0088] Electric driving element 1111 includes: stator 1112
connected to an external electric power source (not shown); and
rotor 1113 arranged, forming a predetermined gap between rotor 1113
and stator 1112.
[0089] Compression element 1321 includes: shaft 1122; cylinder
block 1123; bearing 1324; piston 1125; connecting portion 1126; and
thrust ball bearing 1331. Shaft 1122 includes: main shaft portion
1122a, the outer diameter of which is d; and eccentric shaft
portion 1122c formed out of main shaft portion 1122a through flange
portion 1122b. Cylinder block 1123 is fixed in a portion above
stator 1112 and composes compression chamber 1123a. Bearing 1324
supports shaft 1122 provided in cylinder block 1123. Piston 1125
reciprocates in compression chamber 1123a. Connecting portion 1126
connects piston 1125 with eccentric shaft portion 1122c. Thrust
ball bearing 1331 is arranged between flange portion 1122b and an
upper end face of bearing 1124. Compression element 1321 composes a
reciprocating type compression mechanism.
[0090] Rotor 1113 is engaged with main shaft portion 1122a of the
shaft. Stator 1112 is arranged and fixed in a lower portion of
cylinder block 1123.
[0091] Thrust ball bearing 1331 includes: a plurality of balls
1332; holder portion 1333 for holding balls 1332; upper washer 1334
arranged above balls 1332; and lower washer 1335, the outer
diameter of which is b and the inner diameter of which is C,
arranged below balls 1332. On an outer circumference of lower
washer 1335, first bent portion 1341 is formed. It is composed so
that clearance (J-k)/2 in the thrust direction between inner
circumferential diameter J of first bent portion 1341 and outer
diameter k of bearing 1324 can be smaller than clearance (C-d)/2
between inner diameter C of lower washer 1335 and outer diameter d
of main shaft portion 1122a.
[0092] Operation and action of the hermetic compressor composed as
described above will be explained below.
[0093] When stator 1112 is energized by an external electric power
source (not shown), rotor 1113 is rotated together with shaft 1122.
Due to the foregoing, an eccentric motion is conducted by eccentric
shaft portion 1122c. Therefore, eccentric shaft portion 1122c
reciprocates piston 1125 through connecting portion 1126 in
compression chamber 1123a. Accordingly, a predetermined compressive
motion to compress suction gas is conducted.
[0094] At this time, balls 1332 of thrust ball bearing 1331 support
a vertical load generated by the dead weights of rotor 1113 and
shaft 1122. An upper surface of upper washer 1334 is closely
contacted with a lower surface of flange portion 1122b of shaft
1122 through viscosity of refrigerating machine oil 1103.
Therefore, when shaft 1122 is rotated, upper washer 1334 is rotated
synchronously with shaft 1122. On the other hand, a lower surface
of lower washer 1335 is also closely contacted with an upper end
portion of bearing 1324 through viscosity of refrigerating machine
oil 1103. Therefore, lower washer 1335 is not rotated. Since
slippage is generated between rotating balls 1332 and lower washer
1335. Therefore, balls 1332 and holder portion 1333 are rotated
being delayed without following a rotation of shaft 1122. In
general, the coefficient of rolling friction is 10 to 20 times as
low as the coefficient of sliding friction. Further, no metal
contact is caused in the rolling bearing. Therefore, it is possible
to conduct a stable motion by the rolling bearing.
[0095] It is composed so that clearance (J-k)/2 in the thrust
direction between inner circumferential diameter J of first bent
portion 1341 and outer diameter k of bearing 1324 can be smaller
than clearance (C-d)/2 between inner diameter C of lower washer
1335 and outer diameter d of main shaft portion 1122a. Accordingly,
before lower washer 1135 comes into contact with main shaft portion
1122a, the inner circumferential diameter of first bent portion
1341 and the outer diameter of bearing 1324 come into contact with
each other. That is, by first bent portion 1341, lower washer 1335
is surely arranged at a position where the inner diameter of lower
washer 1335 does not come into contact with the outer diameter of
rotating main shaft portion 1122a.
[0096] When first bent portion 1341 or raised portions 1342 is
provided on the outer circumference of lower washer 1335 as
described above, a regulation mechanism is composed.
[0097] Therefore, according to the present embodiment, the inner
diameter of lower washer 1335 can be prevented from coming into
contact with the outer diameter of main shaft portion 1122a by this
regulation mechanism. Accordingly, there is no possibility that
main shaft portion 1122a is damaged by lower washer 1335 and
abrasion powder is generated. Therefore, it is possible to realize
a highly reliable hermetic compressor.
[0098] First bent portion 1341 can be formed, for example,
simultaneously when lower washer 1335 is formed by means of press
forming. Therefore, it is unnecessary to add a manufacturing step
and it is possible to enhance the productivity of a hermetic
compressor.
[0099] Concerning thrust ball bearing 1331, only when shaft 1122 is
inserted into thrust ball bearing 1331 and first bent portion 1341
is idly engaged with bearing 1324 at the time of assembling, it is
possible to incorporate thrust ball bearing 1331. That is, it is
unnecessary to use a special assembling method such as
press-fitting lower washer 1335. Accordingly, the property of
assembling work can be enhanced.
[0100] In this connection, in the present embodiment, first bent
portion 1341 is formed into a shape in which an overall
circumference of lower washer 1335 is subjected to extrusion.
However, of course, the same operational effect can be provided
when three or more raised portions 1342 are provided on the outer
circumference of lower washer 1335 as shown in FIG. 7.
Embodiment 4
[0101] FIG. 8 is a longitudinal sectional view of a hermetic
compressor of Embodiment 4 of the present invention. FIG. 9 is an
enlarged sectional view showing a primary portion of the hermetic
compressor of Embodiment 4 of the present invention.
[0102] In this connection, like reference characters are used to
indicate like parts in Embodiments 1 and 4.
[0103] In FIGS. 8 and 9, refrigerant 1102 is charged into hermetic
container 1101. Further, refrigerating machine oil 1103 is stored
in hermetic container 1101. In this case, refrigerant 1102 is R600a
which is a hydrocarbon refrigerant. Refrigerating machine oil 1103
is an oil, which is compatible with refrigerant 1102, such as
synthetic fluid, mineral oil or polyol ester oil.
[0104] Electric driving element 1111 includes: stator 1112
connected to an external electric power source (not shown); and
rotor 1113 arranged, forming a predetermined gap between rotor 1113
and stator 1112.
[0105] Compression element 1421 includes: shaft 1122; cylinder
block 1123; bearing 1424; piston 1125; connecting portion 1126; and
thrust ball bearing 1431. Shaft 1122 includes: main shaft portion
1122a; and eccentric shaft portion 1122c formed out of main shaft
portion 1122a through flange portion 1122b. Cylinder block 1123 is
fixed in a portion above stator 1112 and composes compression
chamber 1123a. Bearing 1424 supports shaft 1122 provided in
cylinder block 1123. Piston 1125 reciprocates in compression
chamber 1123a. Connecting portion 1126 connects piston 1125 with
eccentric shaft portion 1122c. Thrust ball bearing 1431 is arranged
between flange portion 1122b and an upper end face of bearing 1424.
Compression element 1421 composes a reciprocating type compression
mechanism.
[0106] Rotor 1113 is engaged with main shaft portion 1122a of the
shaft. Stator 1112 is arranged and fixed in a lower portion of
cylinder block 1123.
[0107] Thrust ball bearing 1431 includes: a plurality of balls
1432; holder portion 1433 for holding balls 1432; upper washer 1434
arranged above balls 1432; and lower washer 1435, arranged below
balls 1432. In bearing 1424, at the height in which lower washer
1435 is arranged, first annular protruding portion 1441, which is
surrounded by the inside of the lower washer, is provided.
Therefore, under the condition that the lower surface of lower
washer 1435 is closely contacted with an upper end face of bearing
1424, an inner diameter of lower washer 1435 can not be moved
inside from first annular protruding portion 1441.
[0108] Operation and action of the hermetic compressor composed as
described above will be explained below.
[0109] When stator 1112 is energized by an external electric power
source (not shown), rotor 1113 is rotated together with shaft 1122.
Due to the foregoing, an eccentric motion is conducted by eccentric
shaft portion 1122c. Therefore, eccentric shaft portion 1122c
reciprocates piston 1125 through connecting portion 1126 in
compression chamber 1123a. Accordingly, a predetermined compressive
motion to compress suction gas is conducted.
[0110] At this time, balls 1432 of thrust ball bearing 1431 support
a vertical load generated by the dead weights of rotor 1113 and
shaft 1122. An upper surface of upper washer 1434 is closely
contacted with a lower surface of flange portion 1122b of shaft
1122 through viscosity of refrigerating machine oil 1103.
Therefore, when shaft 1122 is rotated, upper washer 1434 is rotated
synchronously with shaft 1122. On the other hand, a lower surface
of lower washer 1435 is also closely contacted with an upper end
portion of bearing 1424 through viscosity of refrigerating machine
oil 1103. Therefore, lower washer 1435 is not rotated. Slippage is
generated between rotating balls 1432 and lower washer 1435.
Therefore, balls 1432 and holder portion 1433 are rotated being
delayed without following a rotation of shaft 1122. In general, the
coefficient of rolling friction is 10 to 20 times as low as the
coefficient of sliding friction. Further, no metal contact is
caused in the rolling bearing. Therefore, it is possible to conduct
a stable motion by the rolling bearing.
[0111] Since first annular protruding portion 1441 exists between
an inner diameter of lower washer 1435 and an outer diameter of
main shaft portion 1122a, the inner diameter of lower washer 1435
comes into contact with first annular protruding portion 1441
before it comes into contact with the outer diameter of main shaft
portion 1122a. That is, by first annular protruding portion 1441,
the inner diameter of lower washer 1435 is surely arranged at a
position where the inner diameter of lower washer 1435 does not
come into contact with the outer diameter of rotating main shaft
portion 1122a.
[0112] As described above, a regulation mechanism is composed when
first annular protruding portion 1441 is provided inside the upper
end face of bearing 1424.
[0113] Therefore, according to the present embodiment, the inner
diameter of lower washer 1435 can be prevented from coming into
contact with the outer diameter of main shaft portion 1122a by this
regulation mechanism. Accordingly, there is no possibility that
main shaft portion 1122a is damaged by lower washer 1435 and
abrasion powder is generated. Therefore, it is possible to realize
a highly reliable hermetic compressor.
[0114] First annular protruding portion 1441 can be formed, for
example, simultaneously when bearing 1424 is molded by means of
die-cast molding. Therefore, it is unnecessary to add a
manufacturing step. Accordingly, it is possible to enhance the
productivity of producing a hermetic compressor.
[0115] Since thrust ball bearing 1431 can be incorporated into the
device only when shaft 1122 is inserted into the thrust ball
bearing and the inner diameter of lower washer 1435 is idly engaged
with the outer diameter of first annular protruding portion 1441,
it is unnecessary to use a special assembling method such as a
method of press-fitting lower washer 1435. Accordingly, the working
property can be enhanced at the time of assembling.
[0116] In this connection, in the present embodiment, first annular
protruding portion 1441 is arranged at a height in which lower
washer 1435 is arranged. However, as long as first annular
protruding portion 1441 is out of the rotary locus of balls 1432
controlled by holder portion 1433 and as long as first annular
protruding portion 1441 is arranged in a range in which the
rotation of balls 1432 is not obstructed, even when first annular
protruding portion 1441 exceeds the wall thickness of lower washer
1435, the same operational effect can be provided.
Embodiment 5
[0117] FIG. 10 is a longitudinal sectional view of a hermetic
compressor of Embodiment 5 of the present invention. FIG. 11 is an
enlarged sectional view showing a primary portion of the hermetic
compressor of Embodiment 5 of the present invention.
[0118] In FIGS. 10 and 11, refrigerant 2102 is charged into
hermetic container 2101. Further, refrigerating machine oil 2103 is
stored in hermetic container 2101. In this case, refrigerant 2102
is R600a which is a hydrocarbon refrigerant. Refrigerating machine
oil 2103 is an oil, which is compatible with refrigerant 2102, such
as synthetic fluid, mineral oil or polyol ester oil.
[0119] Electric driving element 2111 includes: stator 2112
connected to an external electric power source (not shown); and
rotor 2113 arranged, forming a predetermined gap between rotor 2113
and stator 2112.
[0120] Compression element 2121 includes: shaft 2122; cylinder
block 2123; bearing 2124; piston 2125; connecting portion 2126; and
thrust ball bearing 2131. Shaft 2122 includes: main shaft portion
2122a, the outer diameter of which is d; and eccentric shaft
portion 2122c connected to main shaft portion 2122a. Cylinder block
2123 composes compression chamber 2123a. Bearing 2124 supports
shaft 2122, and is provided being integrated with or separated from
cylinder block 2123. Piston 2125 reciprocates in compression
chamber 2123a. Connecting portion 2126 connects piston 2125 with
eccentric shaft portion 2122c. Thrust ball bearing 2131 is arranged
between an upper end face of bearing 2124 and rotor 2113 fixed to
main shaft portion 2122a. Compression element 2121 composes a
reciprocating type compression mechanism.
[0121] Rotor 2113 is engaged with main shaft portion 2122a of the
shaft. Stator 2112 is arranged and fixed in an upper portion of
cylinder block 2123.
[0122] Thrust ball bearing 2131 includes: a plurality of balls
2132; holder portion 2133 for holding balls 2132; upper washer 2134
arranged above balls 2132; and lower washer 2135 arranged below
balls 2132.
[0123] In bearing 2124, at the height in which lower washer 2135 is
arranged, second cylindrical wall 2141 surrounding the outside of
lower washer 2135 is provided. It is composed so that clearance A
between the outer diameter of lower washer 2135 and the inner
diameter of second cylindrical wall 2141 can be smaller than
clearance c between the inner diameter of lower washer 2135 and the
outer diameter of main shaft portion 2122a.
[0124] Since lower washer 2135 is made of carbon steel of not less
than 70%, the hardness of lower washer 2135 is made to be about 95%
of the hardness of balls 2132 of thrust ball bearing 2131. On
rolling face 2136 with which balls 2132 comes into contact,
flatness is maintained to be not more than 30 microns. Further,
when rolling face 2136 is subjected to quenching, predetermined
hardness can be ensured.
[0125] In the present embodiment, second cylindrical wall 2141
surrounding the outside is formed in such a manner that a stainless
steel sheet is formed into a cylindrical shape. This second
cylindrical wall 2141 is engaged with an outer circumference of an
upper portion of bearing 2124. When the inner diameter of the
cylindrical shape of second cylindrical wall 2141 is made to be a
little smaller than the outer diameter of the outer circumference
of the upper portion of bearing 2124, second cylindrical wall 2141
is fixed onto the outer circumference of the upper portion of
bearing 2124 by an elastic force generated by second cylindrical
wall 2141 itself at the time of engagement.
[0126] Operation and action of the hermetic compressor composed as
described above will be explained below.
[0127] When stator 2112 is energized by an external electric power
source (not shown), rotor 2113 is rotated together with shaft 2122.
Due to the foregoing, an eccentric motion is conducted by eccentric
shaft portion 2122c. Therefore, eccentric shaft portion 2122c
reciprocates piston 2125 through connecting portion 2126 in
compression chamber 2123a. Accordingly, a predetermined compressive
motion to compress suction gas is conducted.
[0128] At this time, balls 2132 of thrust ball bearing 2131 support
a vertical load generated by the dead weights of rotor 2113 and
shaft 2122. An upper surface of upper washer 2134 is closely
contacted with a lower end surface of rotor 2113 fixed to main
shaft portion 2122a through viscosity of refrigerating machine oil
2103. Therefore, when shaft 2122 is rotated, upper washer 2134 is
rotated synchronously with shaft 2122. On the other hand, a lower
surface of lower washer 2135 is also closely contacted with an
upper end portion of bearing 2124 through viscosity of
refrigerating machine oil 2103. Therefore, lower washer 2135 is not
rotated. Since slippage is generated between rotating balls 2132
and lower washer 2135, balls 2132 and holder portion 2133 are
rotated being delayed without following a rotation of shaft 2122.
In general, the coefficient of rolling friction is 10 to 20 times
as low as the coefficient of sliding friction. Further, no metal
contact is caused in the rolling bearing. Therefore, it is possible
to conduct a stable motion by the rolling bearing.
[0129] Clearance A between the outer diameter of lower washer 2135
and the inner diameter of second cylindrical wall 2141 is smaller
than clearance c between the inner diameter of lower washer 2135
and the outer diameter of main shaft portion 2122a. Accordingly,
before lower washer 2135 comes into contact with main shaft portion
2122a, the outer diameter of lower washer 2135 and the inner
diameter of second cylindrical wall 2141 come into contact with
each other. That is, by second cylindrical wall 2141 surrounding
the outside of lower washer 2135, the inner diameter of lower
washer 2135 is arranged at a position where the inner diameter of
lower washer 2135 does not come into contact with the outer
diameter of rotating main shaft portion 2122a.
[0130] When second cylindrical wall 2141 surrounding the outside of
lower washer 2135 is provided in an upper portion of bearing 2124,
a regulation mechanism is composed.
[0131] Therefore, according to the present embodiment, the inner
diameter of lower washer 2135 can be prevented from coming into
contact with the outer diameter of main shaft portion 2122a by this
regulation mechanism. Accordingly, there is no possibility that
main shaft portion 2122a is damaged by lower washer 2135 and
abrasion powder is generated. Therefore, it is possible to realize
a highly reliable hermetic compressor.
[0132] Since it is composed in such a manner that second
cylindrical wall 2141 is formed out of a substantially annular
sheet member and lightly press-fitted into the outer diameter of
bearing 2124, a size of second cylindrical wall 2141 is formed to
be substantially the same as that of the outer diameter of bearing
2124. Therefore, these components are arranged in the minimized
space. Accordingly, there is no possibility that second cylindrical
wall 2141 interferes with other parts even when rotor 2113 exists
in the periphery of bearing 2124.
[0133] Concerning thrust ball bearing 2131, only when shaft 2122 is
inserted into thrust ball bearing 2131 at the time of assembling
and the outer diameter of lower washer 2135 is accommodated in
second cylindrical wall 2141, a regulation means can be easily
provided. Therefore, it is unnecessary to use a special assembling
method of press-fitting lower washer 2135. Accordingly, the
assembling work property can be enhanced.
[0134] In this connection, in the present embodiment, second
cylindrical wall 2141 is formed out of a substantially annular
sheet which is formed differently from bearing 2124. However, of
course, when second cylindrical wall 2141 is formed being
integrated with bearing 2124 into one body, the same effect can be
provided.
Embodiment 6
[0135] FIG. 12 is a longitudinal sectional view of a hermetic
compressor of Embodiment 6 of the present invention. FIG. 13 is an
enlarged sectional view showing a primary portion of the hermetic
compressor of Embodiment 6 of the present invention.
[0136] In FIGS. 12 and 13, refrigerant 2202 is charged into
hermetic container 2201. Further, refrigerating machine oil 2203 is
stored in hermetic container 2201. In this case, refrigerant 2202
is R600a which is a hydrocarbon refrigerant. Refrigerating machine
oil 2203 is an oil, which is compatible with refrigerant 2202, such
as synthetic fluid, mineral oil or polyol ester oil.
[0137] Electric driving element 2211 includes: stator 2212
connected to an external electric power source (not shown); and
rotor 2213 arranged, forming a predetermined gap between rotor 2213
and stator 2212.
[0138] Compression element 2221 includes: shaft 2222; cylinder
block 2223; bearing 2224; piston 2225; connecting portion 2226; and
thrust ball bearing 2231. Shaft 2222 includes: main shaft portion
2222a, the outer diameter of which is d; and eccentric shaft
portion 2222c connected to main shaft portion 2222a. Cylinder block
2223 composes compression chamber 2223a. Bearing 2224 supports
shaft 2222, and is provided being integrated with cylinder block
2223 or being separated from cylinder block 2223. Piston 2225
reciprocates in compression chamber 2223a. Connecting portion 2226
connects piston 2225 with eccentric shaft portion 2222c. Thrust
ball bearing 2231 is arranged between the upper end face of bearing
2224 and rotor 2213 fixed to main shaft portion 2222a. Compression
element 2221 composes a reciprocating type compression
mechanism.
[0139] Rotor 2213 is engaged with main shaft portion 2222a of the
shaft. Stator 2212 is arranged and fixed in an upper portion of
cylinder block 2223.
[0140] Thrust ball bearing 2231 includes: a plurality of balls
2232; holder portion 2233 for holding balls 2232; upper washer 2234
arranged above balls 2232; and lower washer 2235, the inner
diameter of which is C, arranged below the balls 2232. On lower
washer 2235, second recess portion 2241 is provided. On the upper
end face of bearing 2224, second protruding portion 2242 is
provided. These second recess portion 2241 and second protruding
portion 2242 are idly engaged with each other. It is composed in
such a manner that clearance (E-f)/2 in the thrust direction
between width E in the thrust direction of the second recess
portion 2241 and width f in the thrust direction of second
protruding portion 2242 is smaller than clearance (C-d)/2 between
inner diameter C of lower washer 2235 and outer diameter d of main
shaft portion 2222a.
[0141] Since lower washer 2235 is made of carbon steel of not less
than 70%, the hardness of lower washer 2235 is made to be about 95%
of the hardness of balls 2232 of thrust ball bearing 2231. On
rolling face 2236 with which balls 2232 comes into contact,
flatness is maintained to be not more than 30 microns. Further,
when rolling face 2236 is subjected to quenching, predetermined
hardness can be ensured.
[0142] Operation and action of the hermetic compressor composed as
described above will be explained below.
[0143] When stator 2212 is energized by an external electric power
source (not shown), rotor 2213 is rotated together with shaft 2222.
Due to the foregoing, an eccentric motion is conducted by eccentric
shaft portion 2222c. Therefore, eccentric shaft portion 2222c
reciprocates piston 2225 through connecting portion 2226 in
compression chamber 2223a. Accordingly, a predetermined compressive
motion to compress suction gas is conducted.
[0144] At this time, balls 2232 of thrust ball bearing 2231 support
a vertical load generated by the dead weights of rotor 2213 and
shaft 2222. An upper surface of upper washer 2234 is closely
contacted with a lower surface of rotor 2213 fixed to main shaft
portion 2222a through viscosity of refrigerating machine oil 2203.
Therefore, when shaft 2222 is rotated, upper washer 2234 is rotated
synchronously with shaft 2222. On the other hand, a lower surface
of lower washer 2235 is also closely contacted with an upper end
portion of bearing 2224 through viscosity of refrigerating machine
oil 2203. Therefore, lower washer 2235 is not rotated. Since
slippage is generated between rotating balls 2232 and lower washer
2235, balls 2232 and holder portion 2233 are rotated being delayed
without following a rotation of shaft 2222. In general, the
coefficient of rolling friction is 10 to 20 times as low as the
coefficient of sliding friction. Further, no metal contact is
caused in the rolling bearing. Therefore, it is possible to conduct
a stable motion by the rolling bearing.
[0145] Clearance (E-f)/2 in the thrust direction between width E in
the thrust direction of second recess portion 2241 and width f in
the thrust direction of second protruding portion 2242 is smaller
than clearance (C-d)/2 between inner diameter C of lower washer
2235 and outer diameter d of main shaft portion 2222a. Therefore,
before lower washer 2235 comes into contact with main shaft portion
2222a, an end face of second recess portion 2241 and an end face of
second protruding portion 2242 come into contact with each other.
That is, by second recess portion 2241 and second protruding
portion 2242, the inner diameter of lower washer 2235 is surely
arranged at a position where the inner diameter of lower washer
2235 does not come into contact with the outer diameter of rotating
main shaft portion 2222a. Therefore, according to the present
embodiment, there is no possibility that the inner diameter of
lower washer 2235 comes into contact with the outer diameter of
main shaft portion 2222a.
[0146] As described above, when second recess portion 2241 and
second protruding portion 2242, which are idly engaged with each
other, are respectively provided on lower washer 2235 and the upper
end face of bearing 2224, a regulation mechanism is composed.
[0147] Therefore, according to the present embodiment, the inner
diameter of lower washer 2235 can be prevented from coming into
contact with the outer diameter of main shaft portion 2222a by this
regulation mechanism. Accordingly, there is no possibility that
main shaft portion 2222a is damaged by the lower washer 2235 and
abrasion powder is generated. Therefore, it is possible to realize
a highly reliable hermetic compressor.
[0148] Second recess portion 2241 can be formed, for example,
simultaneously when lower washer 2235 is formed by means of press
forming. Second protruding portion 2242 can be formed, for example,
simultaneously when bearing 2242 is molded by means of die-cast
molding. Therefore, it is unnecessary to add a new manufacturing
step. Accordingly, it is possible to enhance the productivity of
producing a hermetic compressor.
[0149] Since thrust ball bearing 2231 can be incorporated into the
device only when shaft 2122 is inserted into the thrust ball
bearing and when second recess portion 2241 and second protruding
portion 2242 are put on each other and the lower washer is arranged
on the upper end face of the bearing at the time of assembling, it
is unnecessary to use a special assembling method such as a method
of press-fitting lower washer 2235. Accordingly, the working
property can be enhanced at the time of assembling.
[0150] In the present embodiment, second recess portion 2241 is a
hollow portion which does not penetrate lower washer 2235. However,
as long as second protruding portion 2242 does not exceed the wall
thickness of lower washer 2235 and second recess portion 2241 is
out of the rotary locus of balls 2232 controlled by holder portion
2233, of course, second recess portion 2241 can provide the same
operational effect as that of a structure in which the second
recess portion 2241 is formed into a hole penetrating lower washer
2235.
[0151] In the present embodiment, second recess portion 2241 is a
hollow portion not penetrating lower washer 2235. However, as long
as second protruding portion 2242 is out of the rotary locus of
balls 2232 controlled by holder portion 2233 and second protruding
portion 2242 is arranged in a range in which second protruding
portion 2242 can not obstruct rotating balls 2232, of course, the
same operational effect can be provided even when second recess
portion 2241 is a hole penetrating lower washer 2235 and second
protruding portion 2242 exceeds the wall thickness of lower washer
2235.
Embodiment 7
[0152] FIG. 14 is a longitudinal sectional view of a hermetic
compressor of Embodiment 7 of the present invention. FIG. 15 is an
enlarged sectional view showing a primary portion of the hermetic
compressor of Embodiment 7 of the present invention.
[0153] In FIGS. 14 and 15, refrigerant 2302 is charged into
hermetic container 2301. Further, refrigerating machine oil 2303 is
stored in hermetic container 2301. In this case, refrigerant 2302
is R600a which is a hydrocarbon refrigerant. Refrigerating machine
oil 2303 is an oil, which is compatible with refrigerant 2302, such
as synthetic fluid, mineral oil or polyol ester oil.
[0154] Electric driving element 2311 includes: stator 2312
connected to an external electric power source (not shown); and
rotor 2313 arranged, forming a predetermined gap between rotor 2313
and stator 2312.
[0155] Compression element 2321 includes: shaft 2322; cylinder
block 2323; bearing 2324; piston 2325; connecting portion 2326; and
thrust ball bearing 2331. Shaft 2322 includes: main shaft portion
2322a, the outer diameter of which is d; and eccentric shaft
portion 2322c connected to main shaft portion 2322a. Cylinder block
2323 composes compression chamber 2323a. Bearing 2324 supports
shaft 2322, and is provided being integrated with cylinder block
2323 or being separated from cylinder block 2323. Piston 2325
reciprocates in compression chamber 2323a. Connecting portion 2326
connects piston 2325 with eccentric shaft portion 2322c. Thrust
ball bearing 2331 is arranged between the upper end face of bearing
2324 and rotor 2313 fixed to main shaft portion 2322a. Compression
element 2321 composes a reciprocating type compression
mechanism.
[0156] Rotor 2313 is engaged with main shaft portion 2322a of the
shaft. Stator 2312 is arranged and fixed in an upper portion of
cylinder block 2323.
[0157] Thrust ball bearing 2331 includes: a plurality of balls
2332; holder portion 2333 for holding balls 2332; upper washer 2334
arranged above balls 2332; and lower washer 2335, arranged below
the balls 2332.
[0158] Lower washer 2335 includes: rolling face 2336 with which
balls 2332 come into contact; and cylindrical second bent portion
2341, the inner diameter of which is C. Clearance (J-k)/2 in the
thrust direction between inner diameter J of second bent portion
2341 and outer diameter k of bearing 2334 is smaller than clearance
(C-d)/2 between inner diameter C of lower washer 2335 and outer
diameter d of main shaft portion 2322a.
[0159] Since lower washer 2335 is made of carbon steel of not less
than 70%, the hardness of lower washer 2335 is made to be about 95%
of the hardness of balls 2332 of thrust ball bearing 2331. On
rolling face 2336 with which balls 2332 comes into contact,
flatness is maintained to be not more than 30 microns. In order to
ensure this flatness, rolling face 2336 is formed by means of
pushing. After that, rolling face 2136 is subjected to quenching so
as to ensure the predetermined hardness and flatness.
[0160] Operation and action of the hermetic compressor composed as
described above will be explained below.
[0161] When stator 2312 is energized by an external electric power
source (not shown), rotor 2313 is rotated together with shaft 2322.
Due to the foregoing, an eccentric motion is conducted by eccentric
shaft portion 2322c. Therefore, eccentric shaft portion 2322c
reciprocates piston 2325 through connecting portion 2326 in
compression chamber 2323a. Accordingly, a predetermined compressive
motion to compress suction gas is conducted.
[0162] At this time, balls 2332 of thrust ball bearing 2231 support
a vertical load generated by the dead weights of rotor 2313 and
shaft 2322. An upper surface of upper washer 2334 is closely
contacted with a lower end surface of rotor 2313 fixed to main
shaft portion 2322a through viscosity of refrigerating machine oil
2303. Therefore, when shaft 2322 is rotated, upper washer 2334 is
rotated synchronously with shaft 2322. On the other hand, a lower
surface of lower washer 2335 is also closely contacted with an
upper end portion of bearing 2324 through viscosity of
refrigerating machine oil 2303. Therefore, lower washer 2335 is not
rotated. Since slippage is generated between rotating balls 2332
and lower washer 2335, balls 2232 and holder portion 2333 are
rotated being delayed without following a rotation of shaft 2322.
In general, the coefficient of rolling friction is 10 to 20 times
as low as the coefficient of sliding friction. Further, no metal
contact is caused in the rolling bearing. Therefore, it is possible
to conduct a stable motion by the rolling bearing.
[0163] Clearance (J-k)/2 in the thrust direction between inner
diameter J of second bent portion 2341 and outer diameter k of
bearing 2334 is smaller than clearance (C-d)/2 between inner
diameter C of lower washer 2335 and outer diameter d of main shaft
portion 2322a. Therefore, before lower washer 2335 comes into
contact with main shaft portion 2322a, inner diameter J of second
bent portion 2341 and outer diameter k of bearing 2324 come into
contact with each other. That is, by second bent portion 2341,
lower washer 2335 is surely arranged at a position where the inner
diameter of lower washer 2335 is not contacted with rotating main
shaft portion 2322a.
[0164] As described above, when second bent portion 2341 is
provided on the outer circumference of lower washer 2335, a
regulation mechanism is composed.
[0165] Therefore, according to the present embodiment, the inner
diameter of lower washer 2335 can be prevented from coming into
contact with the outer diameter of main shaft portion 2322a by this
regulation mechanism. Accordingly, there is no possibility that
main shaft portion 2322a is damaged by the lower washer 2335 and
abrasion powder is generated. Therefore; it is possible to realize
a highly reliable hermetic compressor.
[0166] Concerning thrust ball bearing 2331, only when shaft 2322 is
inserted into thrust ball bearing 2331 and second bent portion 2341
is idly engaged with an upper end of bearing 2324 at the time of
assembling, it is possible to incorporate thrust ball bearing 2331.
That is, it is unnecessary to use a special assembling method such
as press-fitting lower washer 2335. Accordingly, the property of
assembling work can be enhanced.
Embodiment 8
[0167] FIG. 16 is a longitudinal sectional view of a hermetic
compressor of Embodiment 8 of the present invention. FIG. 17 is an
enlarged sectional view showing a primary portion of the hermetic
compressor of Embodiment 8 of the present invention.
[0168] In FIGS. 16 and 17, refrigerant 2402 is charged into
hermetic container 2401. Further, refrigerating machine oil 2403 is
stored in hermetic container 2301. In this case, refrigerant 2402
is R600a which is a hydrocarbon refrigerant. Refrigerating machine
oil 2403 is an oil, which is compatible with refrigerant 2402, such
as synthetic fluid, mineral oil or polyol ester oil.
[0169] Electric driving element 2411 includes: stator 2412
connected to an external electric power source (not shown); and
rotor 2413 arranged, forming a predetermined gap between rotor 2413
and the inside of stator 2412.
[0170] Compression element 2421 includes: shaft 2422; cylinder
block 2423; bearing 2424; piston 2425; connecting portion 2426; and
thrust ball bearing 2431. Shaft 2422 includes: main shaft portion
2422a; and eccentric shaft portion 2422c connected to main shaft
portion 2422a. Cylinder block 2423 composes compression chamber
2423a. Bearing 2424 supports shaft 2422, and is provided being
integrated with cylinder block 2423 or being separated from
cylinder block 2423. Piston 2425 reciprocates in compression
chamber 2423a. Connecting portion 2426 connects piston 2425 with
eccentric shaft portion 2422c. Thrust ball bearing 2431 is arranged
between the upper end face of bearing 2424 and rotor 2413 fixed to
main shaft portion 2422a. Compression element 2421 composes a
reciprocating type compression mechanism.
[0171] Rotor 2413 is engaged with main shaft portion 2422a of the
shaft. Stator 2412 is arranged and fixed in an upper portion of
cylinder block 2423.
[0172] Thrust ball bearing 2431 includes: a plurality of balls
2432; holder portion 2433 for holding balls 2432; upper washer 2434
arranged above balls 2432; and lower washer 2435, arranged below
the balls 2432. In bearing 2424, at the height in which lower
washer 2435 is arranged, second annular protruding portion 2441,
which is surrounded inside the lower washer, is provided.
Therefore, under the condition that the lower surface of lower
washer 2435 is closely contacted with an upper end face of bearing
2424, an inner diameter of lower washer 2435 can not be moved
inside from second annular protruding portion 2441.
[0173] Since lower washer 2435 is made of carbon steel of not less
than 70%, the hardness of lower washer 2435 is made to be about 95%
of the hardness of balls 2432 of thrust ball bearing 2431. On
rolling face 2436 with which balls 2432 comes into contact,
flatness is maintained to be not more than 30 microns. Further,
when rolling face 2436 is subjected to quenching, predetermined
hardness can be ensured.
[0174] Operation and action of the hermetic compressor composed as
described above will be explained below.
[0175] When stator 2412 is energized by an external electric power
source (not shown), rotor 2413 is rotated together with shaft 2422.
Due to the foregoing, an eccentric motion is conducted by eccentric
shaft portion 2422c. Therefore, eccentric shaft portion 2422c
reciprocates piston 2425 through connecting portion 2426 in
compression chamber 2423a. Accordingly, a predetermined compressive
motion to compress suction gas is conducted.
[0176] At this time, balls 2432 of thrust ball bearing 2431 support
a vertical load generated by the dead weights of rotor 2413 and
shaft 2422. An upper surface of upper washer 2434 is closely
contacted with a lower end surface of rotor 2413 fixed to main
shaft portion 2422a through viscosity of refrigerating machine oil
2403. Therefore, when shaft 2422 is rotated, upper washer 2434 is
rotated synchronously with shaft 2422. On the other hand, a lower
surface of lower washer 2435 is also closely contacted with an
upper end portion of bearing 2424 through viscosity of
refrigerating machine oil 2403. Therefore, lower washer 2435 is not
rotated. Since slippage is generated between rotating balls 2432
and lower washer 2435, balls 2432 and holder portion 2433 are
rotated being delayed without following a rotation of shaft 2422.
In general, the coefficient of rolling friction is 10 to 20 times
as low as the coefficient of sliding friction. Further, no metal
contact is caused in the rolling bearing. Therefore, it is possible
to conduct a stable motion by the rolling bearing.
[0177] Since second annular protruding portion 2441 exists between
an inner diameter of lower washer 2435 and an outer diameter of
main shaft portion 2422a, the inner diameter of lower washer 2435
comes into contact with second annular protruding portion 2441
before it comes into contact with the outer diameter of main shaft
portion 2422a. That is, by second annular protruding portion 2441,
the inner diameter of lower washer 2435 is surely arranged at a
position where the inner diameter of lower washer 2435 does not
come into contact with the outer diameter of rotating main shaft
portion 2422a.
[0178] When the annular protruding portion is provided inside the
upper end face of the bearing, a regulation mechanism is
composed.
[0179] Therefore, according to the present embodiment, the inner
diameter of lower washer 2435 can be prevented from coming into
contact with the outer diameter of main shaft portion 2422a by this
regulation mechanism. Accordingly, there is no possibility that
main shaft portion 2422a is damaged and abrasion powder is
generated. Therefore, it is possible to realize a highly reliable
hermetic compressor.
[0180] Second annular protruding portion 2441 can be formed, for
example, simultaneously when bearing 2424 is molded by means of
die-cast molding. Therefore, it is unnecessary to add a
manufacturing step. Accordingly, it is possible to enhance the
productivity of producing a hermetic compressor.
[0181] Since thrust ball bearing 2431 can be incorporated into the
device only when shaft 2422 is inserted into the thrust ball
bearing and when lower washer 2435 is arranged so that the inner
diameter of lower washer 2435 can be laid along the outer diameter
of second annular protruding portion 2441, it is unnecessary to use
a special assembling method such as a method of press-fitting lower
washer 2435. Accordingly, the working property can be enhanced at
the time of assembling.
[0182] In this connection, in the present embodiment, second
annular protruding portion 2441 is arranged at a height in which
lower washer 2435 is arranged. However, as long as second annular
protruding portion 2441 is out of the rotary locus of balls 2432
controlled by holder portion 2433 and as long as second annular
protruding portion 2441 is arranged in a range in which rotation of
balls 2432 is not obstructed, even when second annular protruding
portion 2441 exceeds the wall thickness of lower washer 2435, the
same operational effect can be provided.
INDUSTRIAL APPLICABILITY
[0183] A hermetic compressor of the present invention is highly
efficient and reliable. Therefore, the hermetic compressor of the
present invention can be applied to a refrigerating compressor
incorporated into an air conditioner, a refrigerator and so
forth.
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