JP2018080650A - Swash plate compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a swash plate compressor capable of developing excellent durability.SOLUTION: The swash plate compressor has a first slide layer 5b formed between a swash plate 5 and each of shoes 7a, 7b, and a second slide layer 9b formed between each of cylinder bores 21a, 23a and a piston 9. The first slide layer 5b and the second slide layer 9b each have a binder resin 70 and a solid lubricant. The contact angle of lubricating oil in the first slide layer 5b is smaller than the contact angle of the lubricating oil in the second slide layer 9b.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a swash plate compressor.

  A typical swash plate compressor includes a housing, a drive shaft, a swash plate, a plurality of pairs of shoes, and a plurality of pistons. The housing is formed with a swash plate chamber and a plurality of cylinder bores. The drive shaft is supported by the housing and is rotatable in the swash plate chamber. The swash plate is provided in the swash plate chamber and can rotate synchronously with the drive shaft. Each pair of shoes slides with the swash plate. Each piston reciprocates in each cylinder bore with a stroke corresponding to the inclination angle of the swash plate through a pair of shoes. A first sliding layer is formed on both surfaces of the swash plate on which each shoe slides. A second sliding layer is formed on the peripheral surface of the piston that slides with the cylinder bore.

  Patent Document 1 discloses a resin material that can be used for the first and second sliding layers. This resin material is made of fluororesin such as polytetrafluoroethylene (PTFE), ultrahigh molecular weight polyethylene or the like. In this swash plate compressor, each shoe is preferably slid with respect to the swash plate by the first sliding layer, and the piston is preferably slid with respect to the cylinder bore by the second sliding layer.

JP 2010-60262 A

  However, when the swash plate compressor constitutes a refrigeration circuit for a vehicle together with an evaporator, a condenser, etc., and is operated by being filled with lubricating oil together with refrigerant in the refrigeration circuit, according to the knowledge of the inventors, In the board chamber, there are a part where a lot of lubricating oil exists and a part where there is not much lubricating oil. In particular, lubricating oil hardly exists between the swash plate and each shoe, and lubricating oil tends to exist between the cylinder bore and the piston. On the other hand, according to the knowledge of the inventors, a large amount of lubricating oil is desired between the swash plate and each shoe.

  In this regard, if the first sliding layer is formed of the conventional resin material, depending on the selection of the resin material, wear or seizure may occur between the swash plate and each shoe, which may impair durability.

  This invention is made | formed in view of the said conventional situation, Comprising: It is set as the problem which should be solved to provide the swash plate type compressor which can exhibit the outstanding durability.

The swash plate compressor of the present invention includes a housing in which a swash plate chamber and a plurality of cylinder bores are formed, a drive shaft supported by the housing and rotatable in the swash plate chamber, and provided in the swash plate chamber. A swash plate that can rotate synchronously with a shaft, a shoe that slides on the swash plate, and a refrigerant that contains lubricating oil that reciprocates in each cylinder bore with a stroke according to the inclination angle of the swash plate via the shoe. A piston for compressing
In the swash plate type compressor, a first sliding layer is formed between the swash plate and the shoe, and a second sliding layer is formed between the cylinder bore and the piston.
The first sliding layer and the second sliding layer have a binder resin and a solid lubricant,
The contact angle of the lubricant in the first sliding layer is smaller than the contact angle of the lubricant in the second sliding layer.

  In the swash plate type compressor of the present invention, as shown by the results of experiments by the inventors, the shoe is preferably slid relative to the swash plate by the first sliding layer having the binder resin and the solid lubricant. Further, the piston slides favorably with respect to the cylinder bore by the second sliding layer having the binder resin and the solid lubricant.

  In particular, in this swash plate compressor, the contact angle of the lubricating oil in the first sliding layer is smaller than the contact angle for lubrication in the second sliding layer. For this reason, the first sliding layer has higher oil wettability than the second sliding layer. For this reason, it is difficult for the lubricating oil to exist on the structure of the swash plate compressor, but a large amount of lubricating oil can be present even between the swash plate and the shoe where a large amount of lubricating oil is desired. For this reason, wear and seizure hardly occur between the swash plate and the shoe.

  Further, on the structure of the swash plate type compressor, lubricating oil is likely to be present, but it is possible to prevent so much lubricating oil from being present between the cylinder bore and the piston where not much lubricating oil is desired. That is, the lubricating oil can be moved between the cylinder bore and the piston into the swash plate chamber so that the lubricating oil exists between the swash plate and the shoe.

  Therefore, the swash plate compressor of the present invention can exhibit excellent durability.

  The first and second sliding layers have a binder resin and a solid lubricant. Binder resin has a solid lubricant retention property that makes it difficult to remove the solid lubricant, durability against shearing force that repeatedly acts under the layered film (hardness as a base), abrasion resistance, heat resistance, etc. Demonstrate. As the binder resin, polyamide imide (PAI), polyimide, epoxy resin, phenol resin, or the like can be used. In consideration of cost and characteristics, it is optimal to use PAI as a binder resin.

  The solid lubricant is held by the binder resin and exhibits a low shearing force and a low friction coefficient on the outermost surface. As the solid lubricant, fluororesin, molybdenum dioxide, graphite, ultra high molecular weight polyethylene particles and the like can be employed. The fluororesin and the ultrahigh molecular weight polyethylene particles improve the slipperiness by forming a film on the sliding surfaces of the first and second sliding layers and transferring them to the mating material. Molybdenum dioxide and graphite improve slipperiness by a crystal structure having a low shear force, and realize low friction under a high load. According to the results of experiments by the inventors, the fluororesin has sliding properties such as wear resistance and seizure resistance, but has oil repellency, and the contact angle of the lubricating oil is relatively low. large. On the other hand, the ultra high molecular weight polyethylene particles are inferior to the fluororesin in terms of sliding properties, but have lipophilic properties, and the contact angle of the lubricating oil is relatively small. As the solid lubricant, soft metals such as melamine cyanurate (MCA), calcium fluoride, copper and tin can be employed.

  Further, the first and second sliding layers can have additives in addition to the binder resin and the solid lubricant. As the additive, those that improve the hardness of the first and second sliding layers, such as hard particles such as titanium dioxide, tricalcium phosphate, alumina, silica, silicon carbide, and silicon nitride, can be employed.

  Further, the first and second sliding layers can have a surfactant, a coupling agent, a processing stabilizer, an antioxidant, and the like.

  The solid lubricant of the first sliding layer preferably contains ultra high molecular weight polyethylene, and the solid lubricant of the second sliding layer preferably contains a fluororesin. As described above, since the fluororesin has oil repellency and the ultra high molecular weight polyethylene has oleophilic properties, the solid lubricant of the first sliding layer contains the ultra high molecular weight polyethylene and the second slide. If the solid lubricant in the moving layer contains a fluororesin, the present invention can be reliably realized.

  The swash plate compressor of the present invention has a remarkable effect when the swash plate chamber is directly connected to the evaporator. That is, in a swash plate type compressor in which the swash plate chamber is directly connected to the evaporator, when the liquid refrigerant is returned from the evaporator into the swash plate chamber, the lubricating oil on the shoe and the swash plate is easily flowed by the refrigerant. . For this reason, the first sliding layer between the swash plate and each shoe is easily worn, and seizure is likely to occur. On the other hand, in the swash plate compressor according to the present invention, since the oil wettability of the first sliding layer is high, even if the swash plate chamber is directly connected to the evaporator, the lubricating oil on the first sliding layer is refrigerant. Even if it is flowed, the lubricating oil between the cylinder bore and the piston moves to the swash plate chamber and is introduced between the swash plate and the shoe. It is easy to be supplied in between.

  A swash plate compressor according to the present invention includes a link mechanism that is provided in a swash plate chamber and allows a change in the inclination angle of the swash plate, and an actuator that is provided in the swash plate chamber and changes the inclination angle of the swash plate. If it is, it has a remarkable effect. Here, the actuator is configured to rotate integrally with the drive shaft in the swash plate chamber and to rotate integrally with the drive shaft in the swash plate chamber, and moves in the drive axis direction with respect to the partition body. A movable body that changes the tilt angle, a control body that is partitioned by the partition body and the mobile body, moves the mobile body by the internal pressure, and a control mechanism that controls the pressure in the control pressure chamber. It is preferable.

  That is, a swash plate compressor having such a link mechanism and an actuator has a smaller swash plate chamber volume than a swash plate compressor that changes the inclination angle of the swash plate by controlling the crank chamber pressure. It is difficult to supply lubricating oil to the first sliding layer between the plate and each shoe. For this reason, the first sliding layer between the swash plate and each shoe is easily worn, and seizure is likely to occur. On the other hand, in the swash plate compressor of the present invention, since the oil wettability of the first sliding layer is high, a link mechanism and an actuator are provided. Lubricating oil is difficult to be washed away by the refrigerant.

  The swash plate compressor of the present invention can exhibit excellent durability.

FIG. 1 is a cross-sectional view illustrating a swash plate compressor according to a first embodiment. FIG. 2 is a schematic diagram illustrating a control mechanism in the swash plate compressor according to the first embodiment. FIG. 3 is an enlarged cross-sectional view showing a swash plate, a shoe, and a piston according to the swash plate compressor of the first embodiment. FIG. 4 is a schematic cross-sectional view illustrating the swash plate body and the first sliding layer in the swash plate compressor according to the first embodiment. FIG. 5 is an enlarged cross-sectional view illustrating a cylinder bore and a piston according to the swash plate compressor of the first embodiment. FIG. 6 is a schematic cross-sectional view illustrating the piston body and the second sliding layer in the swash plate compressor according to the first embodiment.

  A first embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, the left side is defined as the front, the right side is defined as the rear, the upper side is defined as the upper side, and the lower side is defined as the lower side. The directions shown in FIGS. 3 and 5 are displayed in correspondence with the directions shown in FIG.

  As shown in FIG. 1, the swash plate type compressor (hereinafter referred to as a compressor) of the first embodiment includes a housing 1, a drive shaft 3, a swash plate 5, a plurality of pairs of shoes 7a and 7b, and a plurality of shoes. Piston 9, link mechanism 11, actuator 13, and control mechanism 15 shown in FIG. 2.

  As shown in FIG. 1, the housing 1 includes a front housing 17, a rear housing 19, a first cylinder block 21, and a second cylinder block 23.

  The front housing 17 is located in front of the compressor. The rear housing 19 is located behind the compressor. The first cylinder block 21 and the second cylinder block 23 are located between the front housing 17 and the rear housing 19.

  The front housing 17 is formed with a first suction chamber 27a and a first discharge chamber 29a. The first suction chamber 27 a is located on the inner peripheral side of the front housing 17. The first discharge chamber 29 a is located on the outer peripheral side of the front housing 17.

  The rear housing 19 is provided with a control mechanism 15. In the rear housing 19, a second suction chamber 27b, a second discharge chamber 29b, and a pressure adjustment chamber 31 are formed. The second suction chamber 27 b is located on the inner peripheral side of the rear housing 19. The second discharge chamber 29 b is located on the outer peripheral side of the rear housing 19. The pressure adjustment chamber 31 is located in the center portion of the rear housing 19. The first discharge chamber 29a and the second discharge chamber 29b are connected by a discharge passage (not shown), and a discharge port (not shown) is formed in the discharge passage.

  A swash plate chamber 33 is formed in the first cylinder block 21 and the second cylinder block 23. The swash plate chamber 33 is located substantially at the center of the housing 1. The swash plate chamber 33 is directly connected to an evaporator (not shown) via a suction port 330 formed in the second cylinder block 23.

  In the first cylinder block 21, a plurality of first cylinder bores 21a are formed concentrically in parallel at equal angular intervals. The first cylinder block 21 is formed with a first shaft hole 21b through which the drive shaft 3 is inserted. The first cylinder block 21 is formed with a first suction passage 37a that communicates the swash plate chamber 33 and the first suction chamber 27a.

  A first valve unit 39 is provided between the front housing 17 and the first cylinder block 21. The first valve unit 39 has the same number of intake ports 39b and discharge ports 39a as the first cylinder bores 21a. Each suction port 39b allows each first cylinder bore 21a to communicate with the first suction chamber 27a via a suction valve (not shown). Each discharge port 39a communicates each first cylinder bore 21a with the first discharge chamber 29a via a discharge valve (not shown). The first valve unit 39 has a communication hole 39c. The first suction chamber 27a communicates with the swash plate chamber 33 through the first suction passage 37a through the communication hole 39c.

  Similar to the first cylinder block 21, a plurality of second cylinder bores 23 a are also formed in the second cylinder block 23. The second cylinder block 23 has a second shaft hole 23b through which the drive shaft 3 is inserted. The second shaft hole 23 b communicates with the pressure adjustment chamber 31. The second cylinder block 23 is formed with a second suction passage 37b that communicates the swash plate chamber 33 and the second suction chamber 27b.

  A second valve unit 41 is provided between the rear housing 19 and the second cylinder block 23. Similar to the first valve unit 39, the second valve unit 41 is formed with the same number of intake ports 41b and discharge ports 41a as the second cylinder bores 23a. Each suction port 41b communicates each second cylinder bore 23a with the second suction chamber 27b via a suction valve 51 (see FIG. 5). Each discharge port 41a allows each second cylinder bore 23a to communicate with the second discharge chamber 29b via a discharge valve 52 (see FIG. 5). The second valve unit 41 has a communication hole 41c. The second suction chamber 27b communicates with the swash plate chamber 33 through the second suction passage 37b through the communication hole 41c.

  The first and second suction chambers 27a and 27b and the swash plate chamber 33 communicate with each other through first and second suction passages 37a and 37b. For this reason, the pressures in the first and second suction chambers 27a and 27b and the swash plate chamber 33 are substantially equal (more strictly speaking, in the swash plate chamber 33 due to the influence of blow-by gas, The pressure is slightly higher than in the suction chambers 27a and 27b.) Since refrigerant gas having passed through the evaporator flows into the swash plate chamber 33 through the suction port 330, each pressure in the swash plate chamber 33 and the first and second suction chambers 27a and 27b is set in the first and second discharge chambers. The pressure is lower than in 29a and 29b.

  A swash plate 5, an actuator 13, and a flange 3a are attached to the drive shaft 3, respectively. The drive shaft 3 is inserted into the first and second shaft holes 21 b and 23 b in the first and second cylinder blocks 21 and 23. Further, the drive shaft 3 is supported around the first and second shaft holes 21b and 23b, so that the drive shaft 3 can rotate around the rotation axis O in the swash plate chamber 33.

  In the drive shaft 3, an axial path 3b extending in the direction of the rotational axis O from the rear end toward the front, and a radial path 3c extending in the radial direction from the front end of the axial path 3b and opening on the outer peripheral surface of the drive shaft 3 are formed. Has been. The rear end of the axis 3 b is open to the pressure adjustment chamber 31. On the other hand, the path 3c is open to a control pressure chamber 13c described later.

  As shown in FIGS. 1 and 3, the swash plate 5 has an annular flat plate shape. The swash plate 5 includes a swash plate body 5a and a first sliding layer 5b. A first sliding layer 5b is formed on the front and rear surfaces of the swash plate body 5a. The swash plate 5 is fixed to the ring plate 45. The ring plate 45 is formed in an annular flat plate shape, and an insertion hole 45a is formed at the center. The swash plate 5 is attached to the drive shaft 3 by the drive shaft 3 being inserted into the insertion hole 45 a and is disposed in the swash plate chamber 33.

  As shown in FIG. 1, the link mechanism 11 has a lug arm 49. The lug arm 49 is disposed in the swash plate chamber 33 and is located on the rear side of the swash plate 5. The lug arm 49 is formed to be substantially L-shaped from one end side to the other end side.

  One end side of the lug arm 49 is connected to the upper end side of the ring plate 45 by the first pin 47a. As a result, the one end side of the lug arm 49 is arranged around the first swing axis M1 with respect to one end side of the ring plate 45, that is, the swash plate 5, with the axis of the first pin 47a as the first swing axis M1. It is supported so that it can swing.

  The other end side of the lug arm 49 is connected to the support member 43 press-fitted to the rear end side of the drive shaft 3 by the second pin 47b. As a result, the other end side of the lug arm 49 swings around the second swing axis M2 with respect to the support member 43, that is, the drive shaft 3, with the second pivot 47b as the second pivot axis M2. It is supported movably.

  In this compressor, the swash plate 5 and the drive shaft 3 are connected by the link mechanism 11, so that the swash plate 5 can rotate synchronously with the drive shaft 3. In addition, the both ends of the lug arm 49 swing around the first swing axis M1 and the second swing axis M2, respectively, thereby allowing the tilt angle of the swash plate 5 to be changed. That is, the link mechanism 11 can change the inclination angle of the swash plate 5.

  As shown in FIG.1 and FIG.5, each piston 9 is comprised from the piston main body 9a and the 2nd sliding layer 9b. A second sliding layer 9b is formed on the entire surface of the piston body 9a. Each piston 9 has a first piston head 9c on the front end side and a second piston head 9d on the rear end side. The first piston head 9c is housed in a reciprocating manner in the first cylinder bore 21a, and forms a first compression chamber 21d. The second piston head 9d is accommodated in the second cylinder bore 23a so as to reciprocate and forms a second compression chamber 23d. Each piston 9 has a recess 9e.

  As shown in FIGS. 1 and 3, the shoes 7a and 7b are each formed in a hemispherical shape. Each shoe 7a, 7b is provided in each recess 9e. Each shoe 7 a, 7 b slides with the swash plate 5. The rotation of the swash plate 5 is converted into the reciprocating motion of the piston 9 by the shoes 7a and 7b. Thus, each piston 9 can reciprocate in each of the first and second cylinder bores 21a, 23a with a stroke corresponding to the inclination angle of the swash plate 5 via the pair of shoes 7a, 7b. Yes.

  As shown in FIG. 1, the actuator 13 is disposed in the swash plate chamber 33 and is located in front of the swash plate 5. The actuator 13 has a partition 13a, a moving body 13b, and a control pressure chamber 13c.

  The partition 13a is formed in a disk shape. The drive shaft 3 is inserted through the partition 13a. The partition 13a is fixed to the drive shaft 3 and provided so as to be rotatable integrally with the drive shaft 3.

  The moving body 13b is located between the flange 3a and the swash plate 5. The moving body 13b is formed in a bottomed cylindrical shape. Further, the drive shaft 3 is inserted through the movable body 13b. The movable body 13b can rotate integrally with the drive shaft 3. Further, a partition 13a is slidably disposed in the moving body 13b. The movable body 13b can move in the direction of the rotational axis O of the drive shaft 3 with respect to the partitioning body 13a. The moving body 13b faces the link mechanism 11 with the swash plate 5 interposed therebetween. Thus, the actuator 13 can rotate integrally with the drive shaft 3 around the rotation axis O.

  A mounting portion 13d is formed at the rear end of the moving body 13b. The attachment portion 13d is connected to the lower end side of the ring plate 45 by the third pin 47c. As a result, the other end side of the ring plate 45 uses the third rocking shaft center with respect to the lower end side of the ring plate 45, that is, the swash plate 5, with the third rocking shaft center M3 serving as the axis of the third pin 47c. It is supported to be swingable around M3. Thus, the moving body 13b is connected to the swash plate 5.

  The control pressure chamber 13c is partitioned by a partition body 13a and a moving body 13b. The control pressure chamber 13c communicates with the pressure adjustment chamber 31 through the radial path 3c and the axial path 3b. The control pressure chamber 13c moves the moving body 13b by the internal pressure. Thereby, the movable body 13b can move in the direction of the rotational axis O of the drive shaft 3 with respect to the partition 13a, and can change the inclination angle of the swash plate 5. That is, the actuator 13 can change the inclination angle of the swash plate 5.

  As shown in FIG. 2, the control mechanism 15 includes a bleed passage 15a and a supply passage 15b as control passages, a control valve 15c, and an orifice 15d. The control mechanism 15 controls the pressure in the control pressure chamber 13c through these.

  The second suction chamber 27b communicates with the pressure adjustment chamber 31 through the extraction passage 15a. The pressure regulation chamber 31 communicates with the control pressure chamber 13c through the axial path 3b and the radial path 3c. That is, the second suction chamber 27b and the control pressure chamber 13c are in communication with each other. Further, an orifice 15d is provided in the extraction passage 15a, and the flow rate of the refrigerant gas flowing through the extraction passage 15a is reduced.

  The second discharge chamber 29b communicates with the pressure adjustment chamber 31 through the air supply passage 15b. The pressure regulation chamber 31 communicates with the control pressure chamber 13c through the axial path 3b and the radial path 3c. That is, the second discharge chamber 29b and the control pressure chamber 13c are in communication with each other. The axial path 3b and the radial path 3c constitute a part of the extraction passage 15a and the supply passage 15b as control passages.

  A control valve 15c is provided in the supply passage 15b. The control valve 15c can adjust the opening degree of the supply passage 15b based on the pressure in the second suction chamber 27b, and can adjust the flow rate of the refrigerant gas flowing through the supply passage 15b. It has become. Public goods can be adopted for the control valve 15c.

  As a characteristic configuration of the compressor of the first embodiment, as shown in FIG. 3, a first sliding layer 5b is formed on the front and rear surfaces of the swash plate body 5a. The swash plate body 5a excluding the first sliding layer 5b in the swash plate 5 is made of an iron-based metal (refers to iron or an iron alloy containing the most iron, the same applies hereinafter). The swash plate body 5a may be an aluminum-based metal (referred to as aluminum or an aluminum alloy containing the most aluminum; hereinafter the same).

As shown in FIG. 4, the first sliding layer 5 b includes a binder resin 70 that is polyamideimide (PAI), ultrahigh molecular weight polyethylene particles (UHPE) 81, molybdenum dioxide (MoS ₂ ) 83, and graphite 84. And a lubricant. These ratios (volume%) are as shown in the sliding layer 1 of Table 1. UHPE has an average particle diameter of 1 to 30 μm and an average molecular weight of 500,000. When the particle size is smaller than 1 μm, it is difficult to handle because it is easy to condense, and when it is larger than 30 μm, the surface roughness of the layer increases and the sliding performance deteriorates. Moreover, when molecular weight is smaller than 500,000, abrasion resistance deteriorates.

  The shoes 7a and 7b that slide on the sliding surface of the first sliding layer 5b are also made of an iron-based metal. The shoes 7a and 7b may also be aluminum metal. Further, the shoes 7a and 7b can be constituted by the shoe main body and the first sliding layer 5b.

  Further, a second sliding layer 9b is formed on the entire surface of each piston 9 as shown in FIG. The piston main body 9a excluding the second sliding layer 9b in the piston 9 is made of an aluminum-based metal. The piston body 9a may be an iron-based metal.

  As shown in FIG. 6, the second sliding layer 9 b includes a binder resin 70 that is PAI and PTFE 82 that is a solid lubricant. These ratios (volume%) are as shown in the sliding layer 4 of Table 1. That is, the solid lubricant is composed only of PTFE 82.

  The first and second cylinder blocks 21 and 23 that slide with the sliding surface of the second sliding layer 9b are made of an aluminum-based metal. The first and second cylinder blocks 21 and 23 may be iron-based metal. Also, the first and second cylinder blocks 21 and 23 can be constituted by the first and second cylinder block bodies and the second sliding layer 9b.

  The first and second sliding layers 5b and 9b are produced as follows. First, each solid lubricant is blended in the PAI varnish and well disturbed. Then, the mixture is passed between three roll mills to obtain a paint. This paint can be optionally coated with n-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, for adjustment of the type of coating method (spray coating, roll coating, etc.), viscosity adjustment, solid content concentration adjustment, etc. Or it is diluted with a solvent such as xylene. Then, the swash plate body 5a and the piston body 9a are coated with a paint, dried, and then fired (230 ° C. × 1 hour). The coating film thus obtained is adjusted to a film thickness of 20 μm to form first and second sliding layers 5b and 9b.

  In the compressor of Example 1 obtained in this way, piping connected to the evaporator is connected to the suction port 330 shown in FIG. 1, and piping connected to a condenser (not shown) is connected to the discharge port. A compressor, an evaporator, an expansion valve, a condenser, and the like constitute a refrigeration circuit for a vehicle air conditioner.

  In this compressor, when the drive shaft 3 rotates, the swash plate 5 rotates and each piston 9 reciprocates in the first and second cylinder bores 21a and 23a. For this reason, the first and second compression chambers 21d and 23d change in volume according to the piston stroke. Therefore, the refrigerant gas sucked into the swash plate chamber 33 from the evaporator through the suction port 330 is compressed in the first and second compression chambers 21d and 23d via the first and second suction chambers 27a and 27b, and the first, The two discharge chambers 29a and 29b are discharged. The refrigerant gas in the first and second discharge chambers 29a and 29b is discharged from the discharge port to the condenser.

  In the meantime, in this compressor, each shoe 7a, 7b slides suitably with respect to the swash plate 5 by the 1st sliding layer 5b. Also, each piston 9 slides favorably with respect to each of the first and second cylinder bores 21a, 23a by the second sliding layer 9b.

  In particular, in this compressor, the lubricating oil can be moved between the cylinder bores 21a, 23a and the piston 9 to the swash plate chamber 33 to increase the lubricating oil between the swash plate 5 and the shoes 7a, 7b. The first sliding layer 5b has higher oil wettability than the second sliding layer 9b. For this reason, even between the swash plate 5 and the shoes 7a and 7b, a large amount of lubricating oil can be present. For this reason, wear and seizure hardly occur between the swash plate 5 and the shoes 7a and 7b.

  Further, it is possible to prevent so much lubricating oil from being present between each of the first and second cylinder bores 21a, 23a and each piston 9. Therefore, the lubricating oil between the first and second cylinder bores 21 a and 23 a and the pistons 9 can be moved to the swash plate chamber 33.

  Therefore, the compressor of Example 1 can exhibit excellent durability.

(test)
In order to confirm the effect of Example 1, each test piece having sliding layers 1 to 5 was prepared. The base material corresponding to the swash plate body or the piston body in each test piece is cast iron. The ratio (volume%) of the binder resin and the solid lubricant in the sliding layers 1 to 5 in each test piece is as shown in Table 1. Each test piece has the same mass.

  Table 2 shows the basic characteristics of the fluororesin (PTFE) and ultrahigh molecular weight polyethylene particles (UHPE) constituting the composition of the sliding layers 1, 2, 4, and 5.

  The contact angle of the lubricating oil in the sliding layers 1 to 5 of each test piece is as shown in Table 1. Here, polyalkylene glycol (PAG) was used as the lubricating oil. The lubricating oil may be polyol ester (POE) or the like. From Table 1, it can be seen that the sliding layers 1 and 2 have oleophilic properties since the contact angle is small. On the other hand, since the sliding layers 4 and 5 have a larger contact angle than the sliding layers 1 and 2, it can be seen that they have oil repellency.

  Moreover, the following test 1 and test 2 were implemented with respect to the sliding layers 1-3 of each test piece.

Test 1: Ring-on-disk evaluation S45C was used as the material for the other ring, and the coefficient of friction and specific wear were determined under the conditions of no lubrication (no lubricating oil), sliding speed: 9 m / sec, and load 220 N.

Test 2: Evaluation of swash plate / shoe, step load seizure Under oil lubrication (with lubricating oil: refrigeration oil attached to the surface of the swash plate at 25 g / min), load 400N was applied every 5 minutes, and the rotation speed was 1500 rpm. Then, step load seizure evaluation was performed. The load that caused seizure was determined. The results are shown in Table 3.

  The sliding layers 1 and 2 have a lower coefficient of friction, less friction, and improved seizure resistance compared to the sliding layer 3. This is because the sliding layers 1 and 2 contain UHPE as a solid lubricant.

  Further, the solid lubricant of the sliding layers 1 and 2 contains UHPE, whereas the solid lubricant of the sliding layers 4 and 5 does not contain UHPE, but instead contains PTFE. For this reason, the sliding layers 1 and 2 containing UHPE are less worn and have better seizure resistance than the sliding layers 4 and 5 containing PTFE. Accordingly, it is understood that the sliding layers 1 and 2 have high lipophilic properties, improve oil wettability, form an oil film, and have excellent wear resistance.

  In the above, the present invention has been described with reference to Example 1 and Tests 1 and 2. However, the present invention is not limited to Example 1 described above, and can be appropriately modified and applied without departing from the spirit of the present invention. Needless to say.

  The present invention can be used for an air conditioner or the like.

DESCRIPTION OF SYMBOLS 1 ... Housing 3 ... Drive shaft 5 ... Swash plate 5b ... 1st sliding layer 7a, 7b ... Shoe 9 ... Piston 9b ... 2nd sliding layer 11 ... Link mechanism 13 ... Actuator 13a ... Partition body 13b ... Moving body 13c ... Control pressure chamber 15 ... Control mechanism 33 ... Swash plate chamber 21a ... First cylinder bore (cylinder bore)
23a ... Second cylinder bore (cylinder bore)
70 ... Binder resin 81 ... UHPE (ultra high molecular weight polyethylene)
82 ... PTFE (Fluororesin)

Claims (4)

A housing in which a swash plate chamber and a plurality of cylinder bores are formed; a drive shaft supported by the housing and rotatable in the swash plate chamber; a swash plate provided in the swash plate chamber and rotatable in synchronization with the drive shaft; A shoe that slides with the swash plate, and a piston that reciprocates in each cylinder bore with a stroke according to the inclination angle of the swash plate via the shoe, and compresses a refrigerant containing lubricating oil,
In the swash plate type compressor, a first sliding layer is formed between the swash plate and the shoe, and a second sliding layer is formed between the cylinder bore and the piston.
The first sliding layer and the second sliding layer have a binder resin and a solid lubricant,
The contact angle of the lubricating oil in the first sliding layer is smaller than the contact angle of the lubricating oil in the second sliding layer.   2. The swash plate compressor according to claim 1, wherein the solid lubricant of the first sliding layer includes ultra high molecular weight polyethylene, and the solid lubricant of the second sliding layer includes a fluororesin.   The swash plate compressor according to claim 1 or 2, wherein the swash plate chamber is directly connected to an evaporator. A link mechanism that is provided in the swash plate chamber and allows the inclination angle of the swash plate to be changed, and an actuator that is provided in the swash plate chamber and changes the inclination angle of the swash plate;
The actuator is configured to rotate integrally with the drive shaft in the swash plate chamber, and to rotate integrally with the drive shaft in the swash plate chamber, and in the direction of the drive axis with respect to the partition A control body that is moved by an internal pressure to change the tilt angle, is divided by the partition body and the mobile body, and moves the mobile body by an internal pressure, and controls the pressure in the control pressure chamber The swash plate type compressor according to claim 3, further comprising a control mechanism.

Images