U.S. patent application number 14/221709 was filed with the patent office on 2014-10-23 for refrigerant compressor.
This patent application is currently assigned to MITSUBISHI ELECTRIC CORPORATION. The applicant listed for this patent is MITSUBISHI ELECTRIC CORPORATION. Invention is credited to Hideaki MAEYAMA, Koichi SATO.
Application Number | 20140314607 14/221709 |
Document ID | / |
Family ID | 51478141 |
Filed Date | 2014-10-23 |
United States Patent
Application |
20140314607 |
Kind Code |
A1 |
MAEYAMA; Hideaki ; et
al. |
October 23, 2014 |
REFRIGERANT COMPRESSOR
Abstract
A refrigerant compressor configured to compress ethylene
fluorohydrocarbon or a mixture containing the ethylene
fluorohydrocarbon as a refrigerant, the refrigerant compressor
including: a compression element configured to compress the
refrigerant and including a sliding component that constitutes a
sliding portion; and refrigerator oil configured to be supplied to
the sliding component so as to lubricate the sliding portion,
wherein at least one of the sliding surfaces of the sliding
component is formed by non-metal, and wherein a polymerization
inhibitor configured to suppress polymerization of the refrigerant
is contained in the refrigerator oil.
Inventors: |
MAEYAMA; Hideaki; (Tokyo,
JP) ; SATO; Koichi; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MITSUBISHI ELECTRIC CORPORATION |
Tokyo |
|
JP |
|
|
Assignee: |
MITSUBISHI ELECTRIC
CORPORATION
Tokyo
JP
|
Family ID: |
51478141 |
Appl. No.: |
14/221709 |
Filed: |
March 21, 2014 |
Current U.S.
Class: |
418/63 ;
418/83 |
Current CPC
Class: |
F04C 2210/263 20130101;
F04C 2240/605 20130101; F04C 2240/56 20130101; F04C 18/3564
20130101 |
Class at
Publication: |
418/63 ;
418/83 |
International
Class: |
F04C 18/356 20060101
F04C018/356; F04C 29/02 20060101 F04C029/02 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 17, 2013 |
JP |
2013-086267 |
Claims
1. A refrigerant compressor configured to compress ethylene
fluorohydrocarbon or a mixture containing the ethylene
fluorohydrocarbon as a refrigerant, the refrigerant compressor
comprising: a compression element configured to compress the
refrigerant and including a sliding component that constitutes a
sliding portion; and refrigerator oil configured to be supplied to
the sliding component so as to lubricate the sliding portion,
wherein at least one of the sliding surfaces of the sliding
component is formed by non-metal, and wherein a polymerization
inhibitor configured to suppress polymerization of the refrigerant
is contained in the refrigerator oil.
2. A refrigerant compressor configured to compress ethylene
fluorohydrocarbon or a mixture containing the ethylene
fluorohydrocarbon as a refrigerant, the refrigerant compressor
comprising: a compression element configured to compress the
refrigerant and including a sliding component that constitutes a
sliding portion, wherein the sliding component is a sintered
component in which a polymerization inhibitor configured to
suppress polymerization of the refrigerant is contained, and
wherein at least one of the sliding surfaces of the sliding
component is formed by non-metal.
3. A refrigerant compressor configured to compress ethylene
fluorohydrocarbon or a mixture containing the ethylene
fluorohydrocarbon as a refrigerant, the refrigerant compressor
comprising: a compression element configured to compress the
refrigerant and including a sliding component that constitutes a
sliding portion; and an electric element configured to drive the
compression element and including windings, wherein a
polymerization inhibitor configured to suppress polymerization of
the refrigerant is contained in a gap between the windings, and
wherein at least one of the sliding surfaces of the sliding
component is formed by non-metal.
4. The refrigerant compressor according to claim 1, wherein the
ethylene fluorohydrocarbon includes at least one of fluoroethylene
(R1141), trans-1,2 difluoroethylene (R1132 (E)), cis-1,2
difluoroethylene (R1132 (Z)), 1,1 difluoroethylene (R1132a), and
1,1,2 trifluoroethylene (R1123).
5. The refrigerant compressor according to claim 1, wherein the
polymerization inhibitor is a terpin compound.
6. The refrigerant compressor according to claim 5, wherein the
terpin compound is at least one of limonene, pinene, camphene,
cymene, terpinen, citronellol, terpineol and bornelol.
7. The refrigerant compressor according to claim 1, wherein the
non-metal is formed by performing a coating process on the surface
of the sliding component.
8. The refrigerant compressor according to claim 7, wherein one of
DLC (diamond like carbon), DLC-Si (diamond like carbon-silicon),
CrN (chromium nitride), TiN (titanium nitride), TiCN (titanium
carbonitride), TiAlN (titanium nitride aluminum), WC/C (tungsten
carbide coating) and VC (vanadium carbide) is coated as a coating
in the coating process.
9. The refrigerant compressor according to claim 1, wherein the
non-metal is configured by a non-metallic bearing member.
10. The refrigerant compressor according to claim 9, wherein the
non-metallic bearing member contains PTFE (polytetrafluoroethylene)
or POM (polyacetal) as a main component.
11. The refrigerant compressor according to claim 1, wherein at
least one of the components constituting the sliding portion is
formed by a ceramic material.
12. The refrigerant compressor according to claim 11, wherein the
ceramic material is one of SiC (silicon carbide), ZrO.sub.2
(zirconium dioxide), Al.sub.2O.sub.3 (aluminum oxide) and
Si.sub.3N.sub.4 (silicon nitride).
13. The refrigerant compressor according to claim 1, wherein the
non-metal is configured by a manganese phosphate film.
14. The refrigerant compressor according to claim 1, wherein the
compression element includes, a ring-shaped rolling piston
configured to eccentrically rotate within a cylinder chamber of a
cylinder, and a vane accommodated in a vane groove of the cylinder
and configured to slide within the vane groove while being pressed
against the rolling piston, and wherein the sliding portion is
constituted of a leading end of the vane and an outer periphery of
the rolling piston.
15. The refrigerant compressor according to claim 1, wherein the
compression element includes, a cylinder including a vane groove,
and a vane accommodated in the vane groove of the cylinder and
configured to slide within the vane groove, and wherein the sliding
portion is constituted of the vane groove and the vane.
16. The refrigerant compressor according to claim 1, wherein the
compression element includes, a ring-shaped rolling piston
configured to eccentrically rotate within a cylinder chamber of a
cylinder, and a crank shaft having an eccentric shaft portion
eccentric to a main shaft portion, and wherein the sliding portion
is constituted of an inner periphery of the rolling piston and the
eccentric shaft portion of the crank shaft.
17. The refrigerant compressor according to claim 1, wherein the
compression element includes, a crank shaft having a main shaft
portion and an auxiliary shaft portion, a main bearing configured
to slidably engage with the main shaft portion of the crank shaft,
and an auxiliary bearing configured to slidably engage with the
auxiliary shaft portion of the crank shaft, and wherein the sliding
portion is constituted of the main bearing, the auxiliary bearing
and the crank shaft.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from Japanese Patent
Application No. 2013-086267 filed on Apr. 17, 2013, the entire
contents of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] Aspects of the invention relate to a refrigerant compressor
for use in a refrigerator/air-conditioner and, specifically, to a
refrigerant compressor using ethylene fluorohydrocarbon or a
mixture containing the ethylene fluorohydrocarbon as a
refrigerant.
BACKGROUND
[0003] In the field of a car air-conditioner, as a low GWP (Global
Warming Potential) refrigerant, there is known HFO-1234yf
(CF.sub.3CF.dbd.CH.sub.2) which is propylene fluorohydrocarbon.
[0004] Generally, in propylene fluorohydrocarbon having a double
bond in its composition, due to the presence of the double bond,
resolution or polymerization is easy to occur. Thus, for example,
JP-A-2009-299649 discloses a method for suppressing the resolution
or polymerization of a refrigerant by forming a surface of a
sliding portion of the compressor, where its temperature becomes
high and thus the resolution or polymerization of propylene
fluorohydrocarbon is easy to occur, by a non-metal component.
[0005] Also, tetrafluoroethylene is useful as a monomer for
manufacturing fluoro-resin and a fluorine-containing elastomer
having excellent heat resistance, chemical resistance and the like.
However, since this material is very easy to polymerize, in order
to suppress the polymerization, it is necessary to add a
polymerization inhibitor to tetrafluoroethylene when it is
produced. JP-A-H11-246447 discloses such technology.
SUMMARY
[0006] A refrigerant of HFO-1234yf, which is propylene
fluorohydrocarbon, has a high standard boiling point of -29.degree.
C. and is lower in the operation pressure and smaller in the
refrigeration capacity per suction volume than an R410A refrigerant
(standard boiling point of -51.degree. C.) or the like used in a
stationary air-conditioner. In the stationary air-conditioner, in
order to obtain a refrigeration capacity, which is equivalent to
that of the R410A refrigerant, by using the HFO-1234yf refrigerant,
a volume flow rate of the refrigerant must be increased. In this
case, there were problems due to increase in a displacement of the
compressor, and problems of increase in the pressure loss of the
refrigerant and deterioration in the efficiency due to the
increased volume flow rate.
[0007] Thus, when a low GWP refrigerant is applied to a stationary
air-conditioner, a low GWP refrigerant of a low standard boiling
point is suitable. Generally, there is a tendency that, the smaller
the carbon number of a refrigerant is, the lower the low boiling
point thereof is. Therefore, when compared with using propylene
fluorohydrocarbon whose carbon umber is 3 as in related-art, by
using ethylene fluorohydrocarbon whose carbon number is 2, a
compound of a low boiling point, that is, a refrigerant of a low
boiling point can be obtained.
[0008] However, when compared with propylene fluorohydrocarbon,
since ethylene fluorohydrocarbon is high in reactivity, is
thermally and chemically unstable and is easy to resolve or
polymerize, it is difficult to suppress the resolution or
polymerization by using only the method disclosed in
JP-A-2009-299649.
[0009] Also, when ethylene fluorohydrocarbon is used as the
refrigerant, resolution or polymerization is easy to occur from
just after the time of production of the refrigerant, and even
during the storage thereof, resolution or polymerization occurs. To
suppress the resolution or polymerization of the refrigerant at and
after the storage thereof, to a refrigerant constituted of ethylene
fluorohydrocarbon, polymerization inhibitor as disclosed in, for
example, JP-A-H11-246447, is added to the refrigerator to suppress
polymerization at and after the time of production of the
refrigerant. Therefore, since the polymerization inhibitor is
contained in the refrigerant, it was thought that there is no need
to add a polymerization inhibitor to the refrigerator oil. However,
even when the polymerization inhibitor has been added to the
refrigerant, since the refrigerant circulates within a
refrigeration circuit while repeating phase change between liquid
and gas, in a sliding portion of a compressor or in a winding
portion of a motor where the temperature becomes high and thus
polymerization is easy to occur, the refrigerant vaporizes. Since
the polymerization inhibitor is contained in the vaporized
refrigerant and is carried out together therewith, it may not be
sufficiently supplied to the sliding portion of the compressor or
the winding portion of the motor, which makes it difficult to
obtain a sufficient suppressing effect on the polymerization of the
refrigerant.
[0010] Especially, when each sliding portion is formed of metal,
due to the mutual sliding operation thereof, the sliding surface
becomes high in temperature to thereby activate the metal of the
sliding surface. Since the activated metal acts as a reaction
catalyst to promote the resolution of ethylene fluorohydrocarbon,
when the polymerization inhibitor is insufficient, the production
of a polymer, which is produced when a resolvent is polymerized, is
promoted.
[0011] Aspects of the invention is made to solve the
above-described problems and an object thereof is to, in a
refrigerant compressor using ethylene fluorohydrocarbon or a
mixture containing the ethylene fluorohydrocarbon as a refrigerant,
suppress resolution of the refrigerant in a sliding portion of a
compression element and also suppress polymerization of the
resolvent of the refrigerant.
[0012] According to an aspect of the invention, there is provided a
refrigerant compressor configured to compress ethylene
fluorohydrocarbon or a mixture containing the ethylene
fluorohydrocarbon as a refrigerant, the refrigerant compressor
including: a compression element configured to compress the
refrigerant and including a sliding component that constitutes a
sliding portion; and refrigerator oil configured to be supplied to
the sliding component so as to lubricate the sliding portion,
wherein at least one of the sliding surfaces of the sliding
component is formed by non-metal, and wherein a polymerization
inhibitor configured to suppress polymerization of the refrigerant
is contained in the refrigerator oil.
[0013] According to another aspect of the invention, there is
provided a refrigerant compressor configured to compress ethylene
fluorohydrocarbon or a mixture containing the ethylene
fluorohydrocarbon as a refrigerant, the refrigerant compressor
including: a compression element configured to compress the
refrigerant and including a sliding component that constitutes a
sliding portion, wherein the sliding component is a sintered
component in which a polymerization inhibitor configured to
suppress polymerization of the refrigerant is contained, and
wherein at least one of the sliding surfaces of the sliding
component is formed by non-metal.
According to another aspect of the invention, there is provided a
refrigerant compressor configured to compress ethylene
fluorohydrocarbon or a mixture containing the ethylene
fluorohydrocarbon as a refrigerant, the refrigerant compressor
including: a compression element configured to compress the
refrigerant and including a sliding component that constitutes a
sliding portion; and an electric element configured to drive the
compression element and including windings, wherein a
polymerization inhibitor configured to suppress polymerization of
the refrigerant is contained in a gap between the windings, and
wherein at least one of the sliding surfaces of the sliding
component is formed by non-metal.
[0014] Accordingly, an increase in the temperature of the sliding
portion of the compression element can be suppressed, the
activation of the metal of the sliding surface can be suppressed,
the resolution of the refrigerant by the activated metal can be
suppressed, and the polymerization of the resolvent of the
refrigerant can be suppressed by the polymerization inhibitor of
the refrigerator oil.
BRIEF DESCRIPTION OF DRAWINGS
[0015] FIG. 1 is a longitudinal section view of a refrigerant
compressor according to embodiment 1 of the present invention;
[0016] FIG. 2 is a section view of the refrigerant compressor
according to the embodiment 1 of the present invention, taken along
the A-A line shown in FIG. 1;
[0017] FIG. 3 is a perspective view of a compression element
component according to embodiment 6 of the present invention;
and
[0018] FIG. 4 is a perspective view of a main bearing 4 (a part of
the main bearing 4 is omitted) according to embodiment 7 of the
present invention.
DETAILED DESCRIPTION
Embodiment 1
[0019] Hereinafter, embodiments of the invention will be described
with reference to a rotary compressor as an example of a
refrigerant compressor. Here, although a single cylinder rotary
compressor will be described as an example, the invention may also
be carried out by using a multiple cylinder rotary compressor.
[0020] FIGS. 1 and 2 show embodiment 1. FIG. 1 is a longitudinal
section view of a rotary compressor 200 and FIG. 2 is a section
view taken along the A-A line shown in FIG. 1.
[0021] Hereinafter, the whole structure of the rotary compressor
200 will be briefly described.
[0022] An example of the rotary compressor 200 shown in FIG. 1 is a
vertical type compressor including a sealed container 20 having
high internal pressure. A compression element 101 is accommodated
in the lower portion of the inside of the sealed container 20. An
electric element 102 for driving the compression element 101 is
accommodated above the compression element 101 in the upper portion
of the inside of the sealed container 20.
[0023] Refrigerator oil 30 for lubricating respective sliding
portions of the compression element 101 is accommodated in the
bottom portion of the inside of the sealed container 20.
[0024] Firstly, the structure of the compression element 101 will
be described. A cylinder 1 containing a compression chamber therein
includes an outer periphery having a substantially circular shape
when viewed from above and also includes therein a cylinder chamber
1b which is a space having a substantially circular shape when
viewed from above. The cylinder chamber 1b is opened at both
axial-direction ends thereof. The cylinder 1 has a predetermined
axial-direction height when viewed from the side.
[0025] The cylinder 1 includes parallel vane grooves 1a formed such
that it penetrates the cylinder 1 in the axial direction. Each vane
groove communicates with the cylinder chamber 1b formed of a
substantially circular space in the cylinder 1 and extends in the
radial direction of the cylinder 1.
[0026] At a back side (outside) of the vane groove 1a, there is
formed a back pressure chamber 1c which is a space communicating
with the vane groove 1a and having a substantially circular shape
when viewed from the above.
[0027] The cylinder 1 has an intake port (not shown) through which
suction gas from an externally provided refrigeration circuit
passes. The intake port penetrates through the cylinder chamber 1b
from the outer peripheral surface of the cylinder 1.
[0028] The cylinder 1 includes a discharge port (not shown) formed
by cutting off a portion adjacent to a circle forming the cylinder
chamber 1b (end face at the electric element 102 side) which is a
substantially circular space.
[0029] The cylinder 1 is made of gray iron, a sinter, carbon steel
or the like.
[0030] A rolling piston 2 eccentrically rotates within the cylinder
chamber 1b. The rolling piston 2 has a ring-like shape and the
inner periphery of the rolling piston 2 is slidably engaged with an
eccentric shaft portion 6a of a crank shaft 6.
[0031] The rolling piston 2 and the cylinder 1 perform the
eccentric movement such that the outer periphery of the rolling
piston 2 almost follows the inner wall of the cylinder chamber 1b
of the cylinder 1.
[0032] The rolling piston 2 is made of, for example, alloy steel
containing chromium or the like.
[0033] A vane 3 is accommodated in the vane groove 1a of the
cylinder 1 and is always pressed against the rolling piston 2 by a
vane spring 8 provided in the back pressure chamber 1c. In the
rotary compressor 200, since the sealed container 20 has high
internal pressure, when the rotary compressor 200 starts its
operation, force caused by a pressure difference between the high
internal pressure of the sealed container 20 and the pressure of
the cylinder chamber 1b acts on the back surface (back pressure
chamber 1c side) of the vane 3. Thus, the vane spring 8 is mainly
used to press the vane 3 against the rolling piston 2 at the start
of the rotary compressor 200 (while no pressure difference exists
between the inside of the sealed container 20 and cylinder chamber
1b).
[0034] A shape of the vane 3 is a flat and is substantially a
rectangular parallelpiped (the thickness in the peripheral
direction is smaller than the lengths in the radial and axial
directions).
[0035] The vane 3 is made mainly of high speed tool steel.
[0036] The main bearing 4 is slidably engaged with the main shaft
portion 6b (the portion above the eccentric shaft portion 6a) of
the crank shaft 6 and closes one end face (at the electric element
102 side) of the cylinder chamber 1b (including the vane groove 1a)
of the cylinder 1.
[0037] The main bearing 4 includes a discharge valve (not shown).
However, the discharge valve may also be included in the main
bearing 4, an auxiliary bearing 5, or both of them.
[0038] The main bearing 4 has a substantially inverted-T shape when
viewed from the side.
[0039] The auxiliary bearing 5 is slidably engaged with the
auxiliary shaft portion 6c (the portion existing downwardly of the
eccentric shaft portion 6a) of the crank shaft 6 and closes the
other end face (existing on the refrigerator oil 30 side) of the
cylinder chamber 1b (including the vane groove 1a) of the cylinder
1.
[0040] The auxiliary bearing 5 has a substantially T-like shape
when viewed at the side.
[0041] The main bearing 4 and the auxiliary bearing 5, similarly to
the cylinder 1, are respectively made of gray iron, a sinter,
carbon steel or the like.
[0042] A discharge muffler 7 is mounted on the outside (the
electric element 102 side) of the main bearing 4. Discharge gas of
high temperature and high pressure, which is discharged from the
discharge valve of the main bearing 4, enters the discharge muffler
7 and is thereafter ejected from the discharge muffler 7 into the
sealed container 20. However, the discharge muffler 7 may also be
provided on the auxiliary bearing 5 side.
[0043] At a lateral side of the sealed container 20, there is
provided a suction muffler 21 which sucks therein refrigeration gas
of low pressure from the refrigeration circuit, and suppresses the
liquid refrigerant from being directly sucked into the cylinder
chamber of the cylinder 1 when liquid refrigerant returns. The
suction muffler 21 is connected through a suction pipe 22 to the
suction port of the cylinder 1. The main body of the suction
muffler 21 is fixed to the side surface of the sealed container 20
by welding or the like.
[0044] Next, the structure of the electric element 102 will be
described. A brushless DC motor is used as the electric element
102. However, an induction motor may also be used as the electric
element 102.
[0045] The electric element 102 includes a stator 12 and a rotor
13. The stator 12 is engaged with and fixed to the inner peripheral
surface of the sealed container 20, and the rotor 13 is disposed
inside the stator 12 with a clearance therebetween.
[0046] The stator 12 includes a stator iron core 12a, which is
produced by punching an electromagnetic steel plate having a
thickness of 0.1 to 1.5 mm into a predetermined shape, laminating a
predetermined number of punched pieces in the axial direction and
fixing them together by caulking, by welding or the like. Further,
the stator 12 includes a three-phase winding 12b wound on a
plurality of teeth portions (not shown) of the stator iron core 12a
by a concentrated winding method. The winding 12b is wound on the
teeth portion through an insulation member 12c. The winding 12b is
made of copper wires coated with AI (amid imide)/EI (ester imide)
or the like. For the insulation member 12c, PET (polyethylene
terephtalate), PBT (polybutylene terephtalate), FEP
(tetrafluoroethylene hexafluoropropylene copolymer (4.6
Fluorinated)), PFA (tetrafluoroethylene perfluoro alkyl vinyl ether
copolymer), PTFE (polytetrafluoroethylene), LCP (liquid crystal
polymer), PPS (polyphenylenesulfide), phenol resin and the like are
mainly used.
[0047] The winding 12b partially projects from the two
axial-direction ends (in FIG. 1, the axial-direction upper and
lower ends) of the stator iron core 12a. The projected portions are
called coil ends. In FIG. 1, the portion designated by the
reference (12b) is one (counter compression element 101 side) coil
end of the winding 12. A lead wire 23 is connected to a terminal
(not shown) which is mounted on the insulation member 12c.
[0048] Notches (not shown) are formed to an outer periphery of the
stator iron core 12a at multiple positions with substantially
regular intervals. These notches constitute one of passages for the
discharge gas which is discharged from the discharge muffler 7 into
the sealed container 20 and also serve as a passage through which
the refrigerant oil 30 returns from the top of the electric element
102 to the bottom of the sealed container 20.
[0049] The rotor 13 arranged inside the stator 12 with a clearance
(normally, about 0.3 to 1 mm) therebetween includes a rotor iron
core 13a, which, similarly to the stator iron core 12a, is produced
by punching an electromagnetic steel plate having a thickness of
0.1 to 1.5 mm into a predetermined shape, laminating a given number
of punched pieces in the axial direction and fixing them together
by caulking, by welding or the like. Further, the rotor 13 includes
a permanent magnet (not shown) to be inserted into a permanent
magnet insertion hole (not shown) formed in the rotor iron core
13a. As the permanent magnet, there is used a magnet such as a
ferrite or a rare earth.
[0050] In order to prevent the permanent magnet inserted in the
permanent magnet insertion hole from falling off in the axial
direction, end plates are provided at the two axial-direction ends
(in FIG. 1, axial-direction upper and lower ends) of the rotor 13.
The rotor 13 includes an upper end plate 13b on the axial-direction
upper end portion and a lower end plate 13c on the axial-direction
lower end portion.
[0051] The upper and lower end plates 13b and 13c serve as rotation
balancers. Further, the upper and lower end plates 13b and 13c are
integrally caulked and fixed by using multiple fixing rivets and
the like (not shown).
[0052] The rotor iron core 13a has multiple penetration holes (not
shown) penetrating therethrough substantially in the axial
direction and serving as gas passages for the discharge gas.
[0053] A terminal 24, which is to be connected to a power supply
serving as the electric power supply source, is fixed to the sealed
container 20 by welding. In the example of FIG. 1, the terminal 24
is provided on the upper surface of the sealed container 20. To the
terminal 24, the lead wire 23 from the electric element 102 is
connected.
[0054] Into the upper surface of the sealed container 20, a
discharge pipe 25 having two open ends is fitted. The discharge gas
discharged from the compression element 101 is discharged from
within the sealed container 20 through the discharge pipe 25 to an
external refrigeration circuit.
[0055] Here, when the electric element 102 is configured by an
induction motor, the rotor 13 has a rotor iron core 13a produced by
punching an electromagnetic steel plate having a thickness of 0.1
to 1.5 mm into a specified shape, laminating a given number of
punched pieces in the axial direction and fixing them together by
caulking by welding or the like. Further, the rotor 13 has and a
squirrel-cage winding produced by filling or inserting a conductor
made of aluminum or copper into a slot formed in the rotor iron
core 13a, while the two ends of the conductor are short-circuited
by an end ring.
[0056] As the refrigeration oil 30 to be accumulated in the bottom
portion of the inside of the sealed container 20, there is used,
for example, POE (polyol ester) which is synthetic oil, PVE
(polyvinyl ether) and AB (arkylbenzen). As the viscosity of the
oil, there is selected the viscosity that sufficiently lubricates
the rotary compressor 200 including the mixing of the refrigerant
into the oil and also prevents the efficiency of the rotary
compressor 200 from being reduced. Generally, the kinematic
viscosity (at 40.degree. C.) of base oil is about 5 to 300
[cSt].
[0057] The refrigerator oil contains 0.1% to 5% of limonene as a
refrigerant polymerization inhibitor.
[0058] In the compressor, trans-1,2, difuluoroethylene (R1132 (E))
which is a low-boiling-point refrigerant similarly to R410A, is
used as the refrigerant.
[0059] General operation of the rotary compressor 200 will be
described. When power is supplied from the terminal 24 and lead
wire 23 to the stator 12 of the electric element 102, the rotor 13
rotates. Then, the crank shaft 6 fixed to the rotor 13 rotates,
whereby the rolling piston 2 rotates eccentrically within the
cylinder chamber 1b of the cylinder 1. A space between the cylinder
chamber 1b of the cylinder 1 and the rolling piston 2 is divided
into two by the vane 3. With the rotation of the crank shaft 6, the
volumes of the two spaces change. Specifically, one space sucks
therein the refrigerant from the suction muffler 21 due to its
gradually increased volume, while the other space compresses the
refrigeration gas therein due to its gradually reduced volume. The
compressed discharge gas is discharged from the discharge muffler 7
into the sealed container 20, then passes through the electric
element 102, and is further discharged from the discharge pipe 25
provided to the sealed container 20 to the outside of the sealed
container 20.
[0060] The discharge gas flowing through the electric element 102
passes through the penetration hole of the rotor 13 of the electric
element 102, an air gap including the slot opening (not shown) of
the stator iron core 12a, notches formed in the outer periphery of
the stator iron core 12a, and the like.
[0061] When the rotary compressor 200 carries out the above
operation, as described below, there are a plurality of sliding
portions where the components slide with each other:
[0062] (1) First sliding portion: Outer periphery 2a of rolling
piston 2 and leading end 3a (inside) of vane 3;
[0063] (2) Second sliding portion: Vane groove 1a of cylinder 1 and
side surface portions 3b of vane 3 (both side surfaces);
[0064] (3) Third sliding portion: Inner periphery 2b of rolling
piston 2 and eccentric shaft portion 6a of crank shaft 6;
[0065] (4) Fourth sliding portion: Inner periphery of main bearing
4 and main shaft portion 6b of crank shaft 6; and,
[0066] (5) Fifth sliding portion: Inner periphery of auxiliary
bearing 5 and auxiliary shaft portion 6c of crank shaft 6.
[0067] Components, which are provided in the compression element
101 and constitute the sliding portions, are as follows:
[0068] (1) Cylinder 1;
[0069] (2) Rolling piston 2;
[0070] (3) Vane 3:
[0071] (4) Main bearing 4;
[0072] (5) Auxiliary bearing 5;
[0073] (6) Crank shaft 6.
[0074] Further, although not shown, there is also known a
swing-type rotary compressor in which, as the drive shaft is
driven, simultaneously when the projection leading end portion of
the vane 3 provided integrally on the rolling piston 2 moves into
and out of a support body along the receiving groove of the support
body, the support body turns. That is, in the swing-type rotary
compressor, the vane 3 advances and retreats in the radial
direction while oscillating according to the revolution of the
rolling piston 2, thereby always dividing the inside of the
cylinder chamber 1b to a compression chamber and a suction
chamber.
[0075] In such swing-type rotary compressor, the projection leading
end portion of the vane 3 and the receiving groove of the support
body constitute the sliding portion.
[0076] Also, between the suction and discharge ports of the
cylinder 1, there is formed a cylindrical hold hole. A support body
constituted of two semi-cylindrical-shaped members each having a
semi-circular-shaped cross section is rotatably engaged to the
cylindrical hold hole. Thereby the outer peripheral surface of the
support body and the tubular hold hole of the cylinder constitute
another sliding portion.
[0077] In this embodiment, since trans-1,2, difuluoroethylene
(R1132 (E)) is used as a refrigerant, the refrigerant is thermally
and chemically unstable and thus resolution or polymerization due
to chemical reaction is easy to occur. When the refrigerant is
polymerized to produce a polymer, there is a possibility that the
inside of the compressor or the refrigeration circuit may be
clogged with such polymer. Especially, in a portion where the
temperature becomes high, the chemical reaction of the refrigerant
is promoted and thus polymerization thereof is easy to occur.
Therefore, to suppress the polymerization of the refrigerant, it is
necessary to take measures, for example, to attach a polymerization
inhibitor to the high temperature portion.
[0078] The above-mentioned sliding portions of the compression
element and the winding portions of the electric element are
portions where the temperatures become high in the compressor. The
sliding portion of the compression element generates heat when the
components of the compression element slide relative to each other,
while the winding portion of the electric element generates heat
when a current is supplied to the winding for rotation of the rotor
13.
[0079] Since ethylene fluorohydrocarbon has high reactivity, even
during storage at room temperature, resolution or polymerization
occurs. Therefore, when using ethylene fluorohydrocarbon as the
refrigerant, when the refrigerant is produced, a polymerization
inhibitor for suppressing the polymerization of the refrigerant is
added to the refrigerant. Even during storage, a polymerization
inhibitor is always mixed into ethylene fluorohydrocarbon. In a
state where ethylene fluorohydrocarbon and polymerization inhibitor
are separated from each other, the refrigerant is not used or kept.
However, within the compressor, since the resolution of the
refrigerant is promoted due to the relative sliding movements of
metals, there is a high possibility that the resolvent is
polymerized. Thus, even when the polymerization inhibitor is
already added to the refrigerant, in the sliding portions of the
compression element and the winding portions of the electric
element which have high temperature, the refrigerant is evaporated,
and the polymerization inhibitor is moved out together with the
evaporated refrigerant and is not left in the high-temperature
portions. Therefore, the effect of the polymerization inhibitor can
not be sufficiently obtained.
[0080] On the other hand, the refrigerator oil 30 accumulated in
the sealed container 20 is supplied to the respective sliding
portions of the compressor by an oiling mechanism (not shown)
provided in the compression element to lubricate the sliding
portions. Generally, the refrigerant and refrigerator oil are
accumulated and transported separately and, when an air-conditioner
is assembled, the refrigerant and refrigerator oil are charged into
the compressor and refrigeration circuit. Therefore, even when a
polymerization inhibitor that suppresses the polymerization of a
refrigerant such as limonene is added to the refrigerator oil,
since the refrigerator oil and the refrigerant do not mix with each
other, the polymerization inhibitor will not act on the
refrigerator oil during storage to suppress the polymerization of
the refrigerant. Therefore, it is not necessary to add the
polymerization inhibitor to the refrigerator oil. Further, even
after the refrigerator oil is charged into the compressor and the
refrigeration circuit, while the compressor is stopping, although
the refrigerant may vaporize and thus may move freely within the
refrigeration circuit, the refrigeration oil is accumulated in the
bottom portion of the sealed container and is unable to move
freely. Therefore, even when the polymerization inhibitor is added
to the refrigeration oil, it will not mix with the refrigerant and
thus the polymerization inhibitor will not act on the refrigerant
to suppress the polymerization thereof. Therefore, while the
compressor is stopping, when the polymerization inhibitor is
already added to the refrigerant, it is not necessary to add the
polymerization inhibitor to the refrigerator oil. However, while
the compressor is operating, by adding a polymerization inhibitor
to the refrigerator oil, the polymerization inhibitor may be
supplied to the sliding portions together with the refrigerator
oil, whereby a sufficient amount of polymerization inhibitor may be
kept at the sliding portions. Thus, even when the sliding portions
become high in temperature, the refrigerant may be suppressed from
being polymerized. Therefore, the polymerization inhibitor may
fulfill its effect. Also, the high-temperature refrigerant
compressed by the compression element, as described above, passes
through the electric element 102 and is discharged outside the
sealed container 20 from the discharge pipe 25 provided on the
upper surface of the sealed container 20. In this case, since the
refrigerant flows fast, a part of the refrigerator oil containing
limonene is conveyed to the electric element while it is molten in
the refrigerant. The refrigerant conveyed to the electric element
collides with the electric element and then the refrigerant and
refrigerator oil are separated from each other, whereby the
refrigerant flows toward the discharge pipe 25 existing upward and
the refrigerator oil returns to the bottom portion of the sealed
container where the refrigerator oil is accumulated. A portion of
the separated refrigerator oil attaches to the winding of the
electric element when colliding with the electric element and is
temporarily kept thereto. Thus, even when the winding becomes high
in temperature, the refrigerant is suppressed from being
polymerized, so that the polymerization inhibitor may provide its
effect.
[0081] As described above, in the sliding portions of the
compression element and the winding portions of the electric
element which become high in temperature in the compressor, by
supplying the refrigerator oil containing limonene as a
polymerization inhibitor, a sufficient amount of polymerization
inhibitor may be kept.
[0082] Also, the polymerization inhibitor contained in the
refrigerant acts on the vaporized refrigerant, thereby effectively
suppressing the polymerization of the refrigerant.
[0083] Thus, at high temperature portions where polymerization is
easy to occur, the polymerization can be suppressed by the
refrigerator oil containing limonene. Therefore, even by using a
refrigerant that easily polymerizes, sufficient reliability can be
maintained.
[0084] In the sliding portions of the compression element, when
each of them are formed by metals, the sliding surfaces thereof
become high in temperature due to the relative sliding movements of
the metals, and the metals of the sliding surfaces are activated.
The activated metal surfaces of the sliding portions act as
reactive catalysts on a thermally and chemically unstable
refrigerant to induce the resolution of the refrigerant. Further,
the exposed metal activated surface of the resultant resolvent acts
as a polymer catalyst to promote the generation of a polymer. The
polymerization inhibitor suppresses not only the polymerization of
the resolvent but also the resolution of the refrigerant, whereby
the action of the polymerization inhibitor may be enhanced further.
That is, in the sliding portions of the compression element, by
suppressing the activated metal surfaces from being exposed, the
catalyst action may be suppressed.
[0085] As will be described hereinafter, at least one of the two
components constituting the sliding portion is formed by a
non-metal material. In the case that one component of the sliding
portion is formed by a non-metal material having low specific heat,
when compared with the relative sliding movements of two metals, a
temperature increase can be reduced, thereby being able to suppress
the sliding portion metal surface from being activated. Thus, the
resolution and polymerization of the refrigerant can be
suppressed.
[0086] Firstly, in the outer periphery of the rolling piston 2 and
the leading end 3a of the vane 3 which constitute the first sliding
portion, the surface of the vane 3 is coated with a carbon DLC-Si
(diamond like carbon-silicone) coating (an example of non-metals).
Thus, in the relative sliding motion between the outer periphery of
the rolling piston 2 and the leading end 3a of the vane 3, direct
contact between metals can be avoided. Accordingly, the first
sliding portion is hard to become high in temperature and the metal
surface is also hard to be activated, thereby being able to
suppress the polymerization of the refrigerant.
[0087] The DLC-Si coating is amorphous carbon containing silicone,
while it has a surface layer hardness of 2000 to 2500 Hmv and a
film thickness of 3 .mu.m or so.
[0088] Also, in the vane groove 1a of the cylinder 1 and the side
surface portion 3b of the vane 3 which constitute the second
sliding portion, by coating the above-mentioned surface of the vane
3 with a DLC-Si coating, the direct contact between metals can be
avoided, and the metal surface is hard to be activated and is hard
to become high in temperature, thereby being able to suppress the
polymerization of the refrigerant.
[0089] In the inner periphery 2b of the rolling piston 2 and the
eccentric shaft portion 6a of the crank shaft 6 which constitute
the third sliding portion, by forming a manganese phosphate film
(an example of non-metals) on the surface the crank shaft 6, the
direct contact between metals can be avoided, and the metal surface
is hard to be activated and is hard to become high in temperature,
thereby being able to suppress the refrigerant from being
polymerized. Here, the manganese phosphate film can also be formed
on the inner periphery 2b of the rolling piston 2.
[0090] In the inner periphery of the main bearing 4 and the main
shaft portion 6b of the crank shaft 6 which constitute the fourth
sliding portion and in the inner periphery of the auxiliary bearing
5 and the auxiliary shaft portion 6c of the crank shaft 6 which
constitute the fifth sliding portion, by forming a manganese
phosphate film on the surface the crank shaft 6, the direct contact
between metals may be avoided, and the metal surface is hard to be
activated and is hard to become high in temperature, thereby being
able to suppress the refrigerant from being polymerized. Here, the
manganese phosphate film may also be formed on the inner
peripheries of the main bearing 4 and the auxiliary bearing 5.
[0091] According to the above structure, in the respective sliding
portions of the rotary compressor 200, since the direct contact
between metals can be avoided, the metal surface serving as the
sliding surface can be suppressed from being activated and the
sliding portions can be suppressed from increasing in temperature,
thereby suppressing the resolution and polymerization of the
refrigerant. This may suppress failure of the rotary compressor 200
and clogging of the refrigeration circuit, which may otherwise be
caused by the resultant polymers of the refrigerant. Thus, the
compressor may provide reliability for a long term.
[0092] Here, the non-metal structure need not be employed in all of
the above sliding portions. Since the activation of the metal
surface is easy to occur in such a portion where the surface
pressure of the sliding portion is large, the sliding speed is
fast, and the state of lubrication is poor, by forming such portion
by a non-metal material, the resolution or polymerization of the
refrigerant can be suppressed and a process for changing such
portion into a non-metal structure may be saved. In a portion where
the surface pressure of the sliding portion is small, the sliding
speed is slow and the lubrication state is good, even when the
sliding portions are respectively made of metals, the sliding
surfaces are hard to be activated. Therefore, it is not always
necessary to change it into a non-metal structure.
[0093] Also, by preventing the direct contact of metals, the
promotion of resolution of the refrigerant is suppressed and the
resolvent of the refrigerant is suppressed from polymerization by
the polymerization inhibitor contained in refrigerator oil.
Therefore, the generation of polymers can be suppressed further and
thus the reliability of the compressor can be enhanced further.
[0094] In the above description, there has been shown an example
using trans-1,2, difluoroethylene (R1132 (E)) as a refrigerant.
However, using fluoroethylene (R1141), cis-1,2 difluoroethylene
(R1132 (Z)), 1,1 difluoroethylene (R1132a), 1,1,2 trifluoroethylene
(R1123) or the like can provide similar effects.
[0095] In the above description, limonene is used as a
polymerization inhibitor contained in the refrigerator oil. However
terpene hydrocarbon such as pecan, camphene, cymene and terpene, or
terpene alcohol such as cirtronellol, terpineol and borneol may
also be used.
Embodiment 2
[0096] The embodiment 1 showed a method in which, in the portion
easy to increase in temperature, a sufficient amount of
refrigerator oil containing a polymerization inhibitor is provided
to thereby suppress polymerization. However, the polymerization
inhibitor may also be contained in the sliding component in
advance. This method will be described hereinafter.
[0097] The cylinder 1, the main bearing 4 and the auxiliary bearing
5 shown in the embodiment 1 may also be configured by porous
sintered components. A polymerization inhibitor or refrigerator oil
containing the polymerization inhibitor is impregnated in these
sintered components in advance and a compressor is then assembled.
In this method, since, within the compressor cylinder or in the
sliding portion easy to increase in temperature, the polymerization
inhibitor leaks out from the sintered components, the
polymerization of the refrigerant can be further suppressed.
[0098] Thus, even when the polymerizing condition of the
refrigerant is satisfied in a state where the amount of the
refrigerator oil charged into the sliding portion of the
compression element is not sufficient, the polymerization of the
refrigerant can be suppressed by the polymerization inhibitor held
by the sintered component.
Embodiment 3
[0099] Other than the sliding portion, in the winding portion of
the electric element which is also easy to increase in temperature,
similarly to the embodiment 2, a polymerization inhibitor may also
be contained in advance. This method will be described
hereinafter.
[0100] In the winding portion 12b of the electric element, when
each winding has a circular section, a gap exists between one
winding and another winding. The gap between the windings,
similarly to the porous property of the sintered component, is
capable of containing and holding therein a polymerization
inhibitor or refrigerator oil containing a polymerization
inhibitor. For example, a polymerization inhibitor is contained in
working oil for use in a winding process, or a winding is immersed
in a polymerization inhibitor. Since a polymerization inhibitor in
the winding portion 12b is sufficiently supplied to the winding
portion where polymerization occurs, the refrigerant polymerization
preventive effect may be enhanced.
[0101] Thus, even when the refrigerant polymerization condition is
satisfied in a state where the amount of the refrigerator oil
charged into the sliding portion of the winding portion of the
electric element is not sufficient, the polymerization of the
refrigerant can be suppressed by the polymerization inhibitor
contained in the winding portion.
Embodiment 4
[0102] The embodiment 1 showed an example of a method for, in five
sliding portions, avoiding direct contact between the metals to
thereby suppress the activation of the metal surfaces and suppress
the temperature increase of the sliding portions. However, as the
method for obtaining a similar effect, several kinds of methods
other than the method of the embodiment 1 are available. This
embodiment 4 shows another method relating to the first sliding
portion constituted of the outer periphery 2a of the rolling piston
2 and the leading end 3a of the vane 3.
[0103] Although the embodiment 1 showed the method for coating the
vane 3 with the DLC-Si coating, as a coating to be applied to the
vane 3, DLC (diamond like carbon), CrN (chromium nitride), TiN
(titanium nitride), TiCN (titanium carbonitride), TiAlN (titanium
nitride aluminum), WC/C (tungsten carbide coating), VC (vanadium
carbide) or the like may also be used. Since no metal is exposed to
the sliding surface of the vane, these coatings also provide a
similar effect to the embodiment 1.
[0104] Also, for the vane 3, besides the above-mentioned method for
covering the surface of the metal with the non-metal coating, there
is also known a method for forming the vane 3 itself by a ceramic
material. The material includes SiC (silicon carbide), ZrO.sub.2
(zirconium dioxide), Al.sub.2O.sub.3 (aluminum oxide),
Si.sub.3N.sub.4 (silicon nitride) and the like. Since use of them
may prevent the metal from being exposed to the sliding surface of
the vane 3, a similar effect to the embodiment 1 can be
obtained.
[0105] Although the embodiment 1 showed the method for suppressing
the metal surface from being exposed to the surface of the vane 3,
a similar method may also be employed in the outer periphery 2a of
the rolling piston 2. When the surface including the outer
periphery 2a of the rolling piston 2 is covered with a coating of
DLC-Si, DLC, CrN, TiN, TiCN, TiAlN, WC/C, VC or the like, the metal
is not exposed to the sliding surface of the outer periphery 2a of
the rolling piston 2. Thus, a similar effect to the embodiment 1
can be obtained.
[0106] Also, for the rolling piston 2 as well, other than the
method for covering the metal surface with the non-metal coating, a
method for forming the rolling piston 2 itself of a ceramic
material may also be employed. The material may include SiC,
ZrO.sub.2, Al.sub.2O.sub.3, Si.sub.3N.sub.4 and the like. Since the
metal is not exposed to the sliding surface of the outer periphery
2a of the rolling piston 2, a similar effect to the embodiment 1
can be obtained.
Embodiment 5
[0107] Similarly to the embodiment 4, embodiment 5 shows an example
relating to the second sliding portion constituted of the vane
groove 1a of the cylinder 1 and the side surface portion 3b of the
vane 3. Like the embodiment 4, the vane 3 may be covered with a
coating of DLC, CrN, TiN, TiCN, TiAlN, WC/C, VC or the like. Thus,
in the second sliding portion as well, since the metal can be
suppressed from being exposed to the sliding surface of the vane 3,
a similar effect to the embodiment 1 can be obtained. When the vane
3 is also formed of ceramics such as SiC, ZrO.sub.2,
Al.sub.2O.sub.3 and Si.sub.3N.sub.4, since the metal is not exposed
to the sliding surface of the vane 3 in the second sliding portion
as well, a similar effect to the embodiment 1 can be obtained.
Embodiment 6
[0108] Embodiment 6 shows another embodiment relating to the third
sliding portion constituted of the inner periphery 2b of the
rolling piston 2 and the eccentric shaft portion 6a of the crank
shaft 6.
[0109] FIG. 3 shows the embodiment 6 and is a perspective view of
the rolling piston 2.
[0110] Although the embodiment 1 showed the method for forming the
manganese phosphate film on the surface of the crank shaft 6,
different measures may also be taken on the rolling piston 2 side,
for example, as shown in FIG. 3, there may be applied a method for
using a bearing member 9 on the inside diameter portion of the
rolling piston 2.
[0111] This bearing member 9 includes two kinds of members. One is
made of metal and the other is made of resin (non-metal). The
resin-made bearing member 9 (an example of non-metal members) is a
characteristic feature of this embodiment.
[0112] Specifically, a bearing member 9 containing PTFE
(polytetrafluoroethylene) or POM (polyacetal) as a main component
can preferably be used. In this case, since the metal is not
exposed to the sliding portion on the rolling piston inside
diameter side, a similar effect to the embodiment 1 can be
obtained.
[0113] Here, the bearing member 9 (an example of non-metal members)
may also be used in the eccentric shaft portion 6a of the crank
shaft 6.
Embodiment 7
[0114] Embodiment 7 shows another example relating to the fourth
sliding portion constituted of the inner periphery of the main
bearing 4 and the main shaft portion 6b of the crank shaft 6 and
the fifth sliding portion constituted of the inner periphery of the
auxiliary bearing 5 and the auxiliary shaft portion 6c of the crank
shaft 6.
[0115] FIG. 4 is a perspective view of the main bearing 4
(partially omitted), showing the seventh embodiment.
[0116] Although the embodiment 1 has showed the method for forming
the manganese phosphate film on the surface of the crank shaft 6,
different measures may also be taken on the main and auxiliary
bearings 4 and 5 side, for example, as shown in FIG. 4, there may
also be employed a method for using a bearing member 10 (an example
of non-metal members) on the inside diameter portion of the main
bearing 4.
[0117] This bearing member 10 includes two kinds of members. One is
made of metal and the other is made of resin. A resin-made bearing
member 10 is a characteristic feature of this embodiment.
[0118] Specifically, a bearing member 10 containing PTFE
(polytetrafluoroethylene) or POM (polyacetal) as a main component
may preferably be used. In this case, since no metal is exposed to
the sliding portion on the inside diameter side of the main bearing
4, a similar effect to the embodiment 4 can be obtained.
[0119] Here, the bearing member 10 may also be used in the main and
auxiliary shaft portions 6b and 6c of the crank shaft 6.
[0120] Although the example in which at least the sliding surface
of one of the components constituting the sliding portions is made
of non-metal has been described, at least the sliding surfaces of
both of the components constituting the sliding portions may be
made of non-metal.
Embodiment 8
[0121] The refrigerator oil used in the above embodiments generally
contains a wear preventing agent. While the wear preventing agent
has a function of preventing the wear of the sliding portions by
the resolution of itself, it is known that the resolvent of the
wear preventing agent reacts with the resolvent of the easily
resolvable ethylene fluorohydrocarbon or its mixture to generate
solids. There is a fear that the solids may accumulate in fine flow
passages such as an expansion valve and a capillary tube within a
refrigeration cycle to cause clogging and thus poor cooling. In
this embodiment, since the refrigerator oil is selected properly
such that it does not include an wear preventing agent, there can
be provided a refrigerant compressor which does not produce solids
generated by the reaction between the resolvent of the wear
preventing agent and ethylene fluorohydrocarbon or the resolvent of
the mixture thereof, nor cause clogging on the refrigeration
circuit, thereby being able to keep excellent performance for a
long period of time.
[0122] The present invention provides illustrative, non-limiting
aspects as follows:
[0123] (1) In a first aspect, there is provided a refrigerant
compressor configured to compress ethylene fluorohydrocarbon or a
mixture containing the ethylene fluorohydrocarbon as a refrigerant,
the refrigerant compressor including: a compression element
configured to compress the refrigerant and including a sliding
component that constitutes a sliding portion; and refrigerator oil
configured to be supplied to the sliding component so as to
lubricate the sliding portion, wherein at least one of the sliding
surfaces of the sliding component is formed by non-metal, and
wherein a polymerization inhibitor configured to suppress
polymerization of the refrigerant is contained in the refrigerator
oil.
[0124] (2) In a second aspect, there is provided a refrigerant
compressor configured to compress ethylene fluorohydrocarbon or a
mixture containing the ethylene fluorohydrocarbon as a refrigerant,
the refrigerant compressor including: a compression element
configured to compress the refrigerant and including a sliding
component that constitutes a sliding portion, wherein the sliding
component is a sintered component in which a polymerization
inhibitor configured to suppress polymerization of the refrigerant
is contained, and wherein at least one of the sliding surfaces of
the sliding component is formed by non-metal.
[0125] (3) In a third aspect, there is provided a refrigerant
compressor configured to compress ethylene fluorohydrocarbon or a
mixture containing the ethylene fluorohydrocarbon as a refrigerant,
the refrigerant compressor including: a compression element
configured to compress the refrigerant and including a sliding
component that constitutes a sliding portion; and an electric
element configured to drive the compression element and including
windings, wherein a polymerization inhibitor configured to suppress
polymerization of the refrigerant is contained in a gap between the
windings, and wherein at least one of the sliding surfaces of the
sliding component is formed by non-metal.
[0126] (4) In a fourth aspect, there is provided the refrigerant
compressor according to any one of the first to third aspects,
wherein the ethylene fluorohydrocarbon includes at least one of
fluoroethylene (R1141), trans-1,2 difluoroethylene (R1132 (E)),
cis-1,2 difluoroethylene (R1132 (Z)), 1,1 difluoroethylene
(R1132a), and 1,1,2 trifluoroethylene (R1123).
[0127] (5) In a fifth aspect, there is provided the refrigerant
compressor according to any one of the first to fourth aspects,
wherein the polymerization inhibitor is a terpin compound.
[0128] (6) In a sixth aspect, there is provided the refrigerant
compressor according to the fifth aspect, wherein the terpin
compound is at least one of limonene, pinene, camphene, cymene,
terpinen, citronellol, terpineol and bornelol.
[0129] (7) In a seventh aspect, there is provided the refrigerant
compressor according to any one of the first to sixth aspects,
wherein the non-metal is formed by performing a coating process on
the surface of the sliding component.
[0130] (8) In an eighth aspect, there is provided the refrigerant
compressor according to the seventh aspect, wherein one of DLC
(diamond like carbon), DLC-Si (diamond like carbon-silicon), CrN
(chromium nitride), TiN (titanium nitride), TiCN (titanium
carbonitride), TiAlN (titanium nitride aluminum), WC/C (tungsten
carbide coating) and VC (vanadium carbide) is coated as a coating
in the coating process.
[0131] (9) In a ninth aspect, there is provided the refrigerant
compressor according to any one of the first to sixth aspects,
wherein the non-metal is configured by a non-metallic bearing
member.
[0132] (10) In a tenth aspect, there is provided the refrigerant
compressor according to the ninth aspect, wherein the non-metallic
bearing member contains PTFE (polytetrafluoroethylene) or POM
(polyacetal) as a main component.
[0133] (11) In an eleventh aspect, there is provided the
refrigerant compressor according to any one of the first to sixth
aspects, wherein at least one of the components constituting the
sliding portion is formed by a ceramic material.
[0134] (12) In a twelfth aspect, there is provided the refrigerant
compressor according to the eleventh aspect, wherein the ceramic
material is one of SiC (silicon carbide), ZrO.sub.2 (zirconium
dioxide), Al.sub.2O.sub.3 (aluminum oxide) and Si.sub.3N.sub.4
(silicon nitride).
[0135] (13) In a thirteenth aspect, there is provided the
refrigerant compressor according to any one of the first to sixth
aspects, wherein the non-metal is configured by a manganese
phosphate film.
[0136] (14) In a fourteenth aspect, there is provided the
refrigerant compressor according to any one of the first to eighth,
eleventh and twelfth aspects, wherein the compression element
includes, a ring-shaped rolling piston configured to eccentrically
rotate within a cylinder chamber of a cylinder, and a vane
accommodated in a vane groove of the cylinder and configured to
slide within the vane groove while being pressed against the
rolling piston, and wherein the sliding portion is constituted of a
leading end of the vane and an outer periphery of the rolling
piston.
[0137] (15) In a fifteenth aspect, there is provided the
refrigerant compressor according to any one of the first to eighth,
eleventh and twelfth aspects, wherein the compression element
includes, a cylinder including a vane groove, and a vane
accommodated in the vane groove of the cylinder and configured to
slide within the vane groove, and wherein the sliding portion is
constituted of the vane groove and the vane.
[0138] (16) In a sixteenth aspect, there is provided the
refrigerant compressor according to any one of the first to sixth,
ninth, tenth and thirteenth aspects, wherein the compression
element includes, a ring-shaped rolling piston configured to
eccentrically rotate within a cylinder chamber of a cylinder, and a
crank shaft having an eccentric shaft portion eccentric to a main
shaft portion, and wherein the sliding portion is constituted of an
inner periphery of the rolling piston and the eccentric shaft
portion of the crank shaft.
[0139] (17) In a seventeenth aspect, there is provided the
refrigerant compressor according to any one the first to sixth,
ninth, tenth and thirteenth aspects, wherein the compression
element includes, a crank shaft having a main shaft portion and an
auxiliary shaft portion, a main bearing configured to slidably
engage with the main shaft portion of the crank shaft, and an
auxiliary bearing configured to slidably engage with the auxiliary
shaft portion of the crank shaft, and wherein the sliding portion
is constituted of the main bearing, the auxiliary bearing and the
crank shaft.
* * * * *