JP2012137013A - Compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a clearance between a roller and a cylinder from getting lost by a difference in their thermal expansion, and also to easily surface-treat the roller.SOLUTION: A compressor includes: a compression chamber; a cylinder having a blade storage communicating with the compression chamber; a first end plate member and a second end plate member disposed at both axial ends of the cylinder; a piston 40 disposed inside the compression chamber and the blade storage; and a pair of bushes disposed inside the blade storage. The piston 40 includes an annular roller 41 provided in the compression chamber and moving along the peripheral wall face of the compression chamber, and a blade 42 extending from the outer peripheral surface of the annular roller 41 and disposed to be capable of coming forward and backward between the pair of bushes disposed in the blade storage. The piston 40 is structured of a substrate 43 made of a hard material with a linear expansion coefficient less than 12×10[/°C], and resin layers 44a-44d covering at least part of the surface of the substrate 43.

Description

  The present invention relates to a compressor that compresses a refrigerant.

  Conventionally, as a compressor, there is a rotary compressor including a cylinder and a roller disposed inside the cylinder. The roller is mounted on a shaft that rotates eccentrically, and moves along the inner peripheral surface of the cylinder as the shaft rotates. Also, in order to prevent seizure due to sliding between the end face of the roller and the end plate member disposed opposite to the end face and between the outer peripheral face of the roller and the inner peripheral face of the cylinder, etc. A minute gap is formed. The size of the gap is preferably as small as possible from the viewpoint of preventing leakage of refrigerant and lubricating oil.

  In the conventional rotary compressor, both the roller and the cylinder are formed of a material having a relatively large thermal expansion coefficient such as iron. Therefore, when the temperature of the roller becomes higher than the temperature of the cylinder, for example, when the compressor is started at a high speed, the amount of thermal expansion of the roller may be larger than the amount of thermal expansion of the cylinder, and the gap described above may be eliminated. is there.

  As a countermeasure against this problem, for example, in the compressor of Patent Document 1, the roller is formed of ceramics having a small thermal expansion coefficient. Thereby, even if the roller temperature becomes higher than the cylinder temperature, it is possible to prevent the gap from being lost.

JP-A-61-66882

However, since ceramics have a high hardness, processing is difficult. Therefore, when forming a roller with ceramics, surface processing is difficult, and processing requires labor and cost.
The same problem occurs when a roller is formed using, for example, a cemented carbide as a material having a small thermal expansion coefficient.
Further, some rotary compressors include a piston in which a roller and a blade projecting from an outer peripheral surface thereof are integrated, and a pair of bushes disposed on both sides of a blade. In the case of this rotary compressor, the same problem as that of the roller described above occurs with respect to the blade and the pair of bushes.
Another rotary compressor includes a roller and a vane that comes into contact with the outer peripheral surface of the roller. In this rotary compressor, the same problem as the above-described roller occurs with respect to the vane.

  Accordingly, an object of the present invention is to provide a compressor including a roller or the like that can prevent gaps from being lost due to a difference in thermal expansion and can easily perform surface processing.

In order to solve the above-described problems, a compressor according to a first aspect of the present invention includes a compression chamber, a cylinder having a blade accommodating portion communicating with the compression chamber, and first end plate members disposed at both axial ends of the cylinder. And a second end plate member, a piston disposed inside the compression chamber and the blade accommodating portion, and a pair of bushes disposed inside the blade accommodating portion, wherein the piston is disposed in the compression chamber. An annular roller that is disposed and moves along the peripheral wall surface of the compression chamber, and a blade that extends from the outer peripheral surface of the roller and is disposed so as to be able to advance and retract between the pair of bushes disposed in the blade housing portion. And at least one of the piston and the pair of bushes includes a base material formed of a high hardness material having a linear expansion coefficient smaller than 12 × 10 ⁻⁶ [/ ° C.], and And a resin layer covering at least a part of the surface of the substrate.

In this compressor, since the coefficient of thermal expansion of the base material constituting the piston or the pair of bushes is smaller than that of iron which is a material of the conventional piston and the pair of bushes, It is possible to prevent a gap between the axial end surfaces of the pair of bushes and the end plate member or a gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber from being lost.
Moreover, since the surface of the base material is covered with a resin layer that can be easily processed, the surface processing can be easily performed.

  A compressor according to a second aspect of the present invention is the compressor according to the first aspect, wherein the resin layer is formed on at least one of the axial end surface of the piston and the outer peripheral surface of the roller. It is characterized by being.

In this compressor, when the resin layer is provided on the axial end surface of the piston, seizure due to sliding can be prevented even if the axial end surface of the piston contacts the end plate member.
Further, when the resin layer is provided on the outer peripheral surface of the roller, even if the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber come into contact with each other, it is possible to prevent the occurrence of seizure due to sliding.

  A compressor according to a third aspect of the invention is the compressor according to the first or second aspect of the invention, wherein the cylinder has a suction hole that opens in a peripheral wall surface of the compression chamber and introduces a refrigerant into the compression chamber. Further, the piston is configured to divide the compression chamber into a high pressure chamber and a low pressure chamber together with the blade while the roller moves along a peripheral wall surface of the compression chamber, and the resin layer includes: The resin layer is formed on the entire surface of the axial end surface of the roller, and the thickness of the resin layer in a part of the region on the high-pressure chamber side half from the root of the blade on the axial end surface of the roller is It is thinner than the minimum thickness in the low pressure chamber side half area from the root portion of the blade at the axial end face, and the remaining half area in the high pressure chamber side half from the root portion of the blade in the axial end face of the roller. The thickness of the minute of the resin layer, characterized in that from the base portion of the blade in the axial end surface of the roller the at most the minimum thickness of the low-pressure chamber side half region.

  In this compressor, the compression chamber is divided into a high pressure chamber and a low pressure chamber by the outer peripheral surface of the roller and the blade, and a portion of the outer peripheral surface of the roller that is in contact with the high pressure chamber to which the refrigerant is compressed is a low pressure chamber to which the refrigerant is supplied. It is exposed to a higher temperature than the side. In the present invention, in the resin layer on the end surface in the axial direction of the roller, the thickness of a part of the region on the high pressure chamber side half from the blade root is made thinner than the region on the low pressure chamber side half from the blade root. The thickness of the resin layer at the time of thermal expansion can be made uniform, and only the portion on the high pressure chamber side of the roller end surface can be prevented from contacting the end plate member.

  The compressor according to a fourth aspect of the present invention is the compressor according to the third aspect, wherein the thickness of the resin layer in the region on the high pressure chamber side half from the root portion of the blade on the axial end surface of the roller is the roller. The thickness of the resin layer in the region on the low pressure chamber side half from the root portion of the blade on the axial end surface of the blade is characterized in that it is thinner.

  In this compressor, in the resin layer on the end surface in the axial direction of the roller, the thickness of the region on the high-pressure chamber side than the blade root is made thinner than the region on the low-pressure chamber side than the blade root, The thickness of the resin layer at the time of thermal expansion can be made uniform, and only the portion on the high pressure chamber side of the roller end surface can be prevented from contacting the end plate member.

  A compressor according to a fifth aspect of the present invention is the compressor according to the third aspect of the present invention, wherein in the resin layer formed on the entire surface of the axial end surface of the roller, the inner side in the radial direction of the root portion of the blade The portion excluding this portion is characterized in that the thickness gradually decreases from the low pressure chamber side end portion of the blade root portion toward the high pressure chamber side end portion of the blade root portion.

  In this compressor, the thickness of the resin layer on the end surface in the axial direction of the roller gradually decreases from the low pressure chamber side toward the high pressure chamber side, so that the thickness of the resin layer during thermal expansion can be made uniform. Further, it is possible to prevent only the portion on the high pressure chamber side of the roller end surface from coming into contact with the end plate member.

  A compressor according to a sixth aspect of the invention is the compressor according to the first or second aspect of the invention, wherein the cylinder has a suction hole that opens in a peripheral wall surface of the compression chamber and introduces a refrigerant into the compression chamber. Further, the piston is configured to divide the compression chamber into a high pressure chamber and a low pressure chamber together with the blade while the roller moves along a peripheral wall surface of the compression chamber, and the resin layer includes: The roller is formed on the entire surface of the axial end surface of the roller, and when the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber is minimized on the axial end surface of the roller, The thickness of the resin layer corresponding to the portion defining the high-pressure chamber in the outer peripheral surface is such that the roller from the axial center of the compression chamber viewed from the axial direction of the compression chamber on the axial end surface of the roller. Extending toward the axial center of When the straight line passing through the end of the suction hole on the downstream side in the moving direction of the roller, the outer peripheral surface of the roller is thinner than the thickness of the resin layer corresponding to the portion defining the low-pressure chamber. It is characterized by.

In this compressor, the compression chamber is divided into a high pressure chamber and a low pressure chamber by the outer peripheral surface of the roller and the blade, and a portion of the outer peripheral surface of the roller that is in contact with the high pressure chamber to which the refrigerant is compressed is a low pressure chamber to which the refrigerant is supplied. Exposed to higher temperatures than the side. In the present invention, when the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber is minimized among the resin layer on the axial end surface of the roller, it corresponds to the portion defining the high-pressure chamber on the outer peripheral surface of the roller The thickness of the portion that is close to the suction hole (the straight line extending from the axial center of the compression chamber toward the axial center of the roller when viewed from the axial direction of the compression chamber is the downstream end of the roller in the movement direction of the roller) Since the thickness of the outer peripheral surface of the roller when passing through the portion is smaller than the thickness of the portion corresponding to the portion that defines the low-pressure chamber), the thickness of the resin layer during thermal expansion can be made uniform. Only the portion on the high pressure chamber side of the end face can be prevented from contacting the end plate member.
In the resin layer on the axial end surface of the roller, when the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber is minimized, the portion corresponding to the portion defining the high pressure chamber in the outer peripheral surface of the roller; As seen from the axial direction of the compression chamber, when a straight line extending from the axial center of the compression chamber toward the axial center side of the roller passes through the end of the suction hole on the downstream side in the moving direction of the roller, The thickness of the portion excluding the portion corresponding to the portion defining the low pressure chamber is such that a straight line extending from the axial center of the compression chamber toward the axial center of the roller as viewed from the axial direction of the compression chamber When passing through the end portion on the downstream side in the movement direction, the thickness is equal to or less than the thickness of the portion corresponding to the portion defining the low-pressure chamber on the outer peripheral surface of the roller.

According to a seventh aspect of the present invention, there is provided a compressor having a compression chamber and a cylinder having a vane accommodating portion communicating with the compression chamber, a first end plate member and a second end plate member disposed at both axial ends of the cylinder, An annular roller disposed inside the compression chamber, and a vane having a tip pressed against an outer peripheral surface of the roller and disposed so as to be able to advance and retreat inside the vane housing portion, and And at least one of the vanes is a substrate formed of a high hardness material having a linear expansion coefficient smaller than 12 × 10 ⁻⁶ [/ ° C.], and a resin layer covering at least a part of the surface of the substrate. It is characterized by having.

In this compressor, since the coefficient of thermal expansion of the base material constituting the roller or vane is smaller than that of iron, which is the material of the conventional roller and vane, the axial end surface of the roller or vane is caused by the thermal expansion of the roller or vane. It is possible to prevent the gap between the end plate member or the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber from being lost.
Moreover, since the surface of the base material is covered with a resin layer that can be easily processed, the surface processing can be easily performed.

  A compressor according to an eighth invention is the compressor according to the seventh invention, wherein the resin layer is formed on the entire surface of at least one of the axial end surface of the roller and the outer peripheral surface of the roller. It is characterized by being.

In this compressor, when a resin layer is provided on the end surface in the axial direction of the roller, seizure due to sliding can be prevented even if the end surface of the roller contacts the end plate member.
Further, when the resin layer is provided on the outer peripheral surface of the roller, even if the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber come into contact with each other, it is possible to prevent the occurrence of seizure due to sliding.

  A compressor according to a ninth invention is the compressor according to any one of the first to eighth inventions, wherein the portion of the surface of the base material covered with the resin layer has an arithmetic average surface roughness Ra. 0.3 or more.

  In this compressor, since the resin layer is bonded to a relatively rough surface, it is difficult to peel off.

  A compressor according to a tenth invention is the compressor according to any one of the first to ninth inventions, wherein the portion of the surface of the base material that is covered with the resin layer is not polished. Features.

In this compressor, the cost and time required for processing the substrate can be reduced.
Moreover, since the resin layer is formed on the rough surface of the substrate that has not been polished, it is difficult to peel off from the substrate.

  A compressor according to an eleventh invention is characterized in that in the compressor according to any one of the first to tenth inventions, the high-hardness material is ceramics or cemented carbide.

  In this compressor, since the base material is formed of ceramics or cemented carbide having a small linear expansion coefficient, it is possible to more reliably prevent the gap from being lost.

  A compressor according to a twelfth aspect of the present invention is the compressor according to any one of the first to eleventh aspects, wherein the resin layer covers corners of the base material.

  In this compressor, since the corners of the substrate are protected by the resin layer, the corners of the substrate can be prevented from being chipped.

  A compressor according to a thirteenth invention is characterized in that, in the compressor according to the twelfth invention, the corner portion of the base material has a chamfered shape.

  In this compressor, since the corners of the substrate are chamfered, the corners can be more reliably prevented from being chipped.

  As described above, according to the present invention, the following effects can be obtained.

In the first invention, since the coefficient of thermal expansion of the base material constituting the piston or the pair of bushes is smaller than that of iron which is a material of the conventional piston and the pair of bushes, Or it can prevent that the clearance gap between the axial direction end surface of a pair of bushes and an end plate member, or the clearance gap between the outer peripheral surface of a roller, and the surrounding wall surface of a compression chamber is lose | eliminated.
Moreover, since the surface of the base material is covered with a resin layer that can be easily processed, the surface processing can be easily performed.

In the second invention, when the resin layer is provided on the axial end surface of the piston, the occurrence of seizure due to sliding can be prevented even if the axial end surface of the piston contacts the end plate member. .
Further, when the resin layer is provided on the outer peripheral surface of the roller, even if the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber come into contact with each other, it is possible to prevent the occurrence of seizure due to sliding.

  In the third invention, the compression chamber is divided into a high pressure chamber and a low pressure chamber by the outer peripheral surface of the roller and the blade, and a portion of the outer peripheral surface of the roller that contacts the high pressure chamber where the refrigerant is compressed is a low pressure to which the refrigerant is supplied. It is exposed to higher temperatures than the room side. In the present invention, in the resin layer on the end surface in the axial direction of the roller, the thickness of a part of the region on the high pressure chamber side half from the blade root is made thinner than the region on the low pressure chamber side half from the blade root. The thickness of the resin layer at the time of thermal expansion can be made uniform, and only the portion on the high pressure chamber side of the roller end surface can be prevented from contacting the end plate member.

  In the fourth aspect of the invention, in the resin layer on the end surface in the axial direction of the roller, the thickness of the half region on the high pressure chamber side with respect to the blade root portion is made thinner than the half region on the low pressure chamber side with respect to the blade root portion. The thickness of the resin layer at the time of thermal expansion can be made uniform, and only the portion on the high pressure chamber side of the roller end surface can be prevented from contacting the end plate member.

  In the fifth invention, since the thickness of the resin layer on the axial end surface of the roller gradually decreases from the low pressure chamber side toward the high pressure chamber side, the thickness of the resin layer during thermal expansion can be made uniform. It is possible to prevent only the high pressure chamber side portion of the roller end surface from contacting the end plate member.

In the sixth invention, the compression chamber is partitioned into a high pressure chamber and a low pressure chamber by the outer peripheral surface of the roller and the blade, and a portion of the outer peripheral surface of the roller that contacts the high pressure chamber where the refrigerant is compressed is a low pressure to which the refrigerant is supplied. It is exposed to higher temperatures than the room side. In the present invention, when the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber is minimized among the resin layer on the axial end surface of the roller, it corresponds to the portion defining the high-pressure chamber on the outer peripheral surface of the roller The thickness of the portion that is close to the suction hole (the straight line extending from the axial center of the compression chamber toward the axial center of the roller when viewed from the axial direction of the compression chamber is the downstream end of the roller in the movement direction of the roller) Since the thickness of the outer peripheral surface of the roller when passing through the portion is smaller than the thickness of the portion corresponding to the portion that defines the low-pressure chamber), the thickness of the resin layer during thermal expansion can be made uniform. Only the portion on the high pressure chamber side of the end face can be prevented from contacting the end plate member.
In the resin layer on the axial end surface of the roller, when the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber is minimized, the portion corresponding to the portion defining the high pressure chamber in the outer peripheral surface of the roller; As seen from the axial direction of the compression chamber, when a straight line extending from the axial center of the compression chamber toward the axial center side of the roller passes through the end of the suction hole on the downstream side in the moving direction of the roller, The thickness of the portion excluding the portion corresponding to the portion defining the low pressure chamber is such that a straight line extending from the axial center of the compression chamber toward the axial center of the roller as viewed from the axial direction of the compression chamber When passing through the end portion on the downstream side in the movement direction, the thickness is equal to or less than the thickness of the portion corresponding to the portion defining the low-pressure chamber on the outer peripheral surface of the roller.

In the seventh invention, since the coefficient of thermal expansion of the substrate constituting the roller or vane is smaller than that of iron which is a material of the conventional roller and vane, the axial end surface of the roller or vane is caused by the thermal expansion of the roller or vane. It is possible to prevent the gap between the end plate member and the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber from being lost.
Moreover, since the surface of the base material is covered with a resin layer that can be easily processed, the surface processing can be easily performed.

In the eighth invention, when the resin layer is provided on the end face in the axial direction of the roller, the occurrence of seizure due to sliding can be prevented even if the end face of the roller comes into contact with the end plate member.
Further, when the resin layer is provided on the outer peripheral surface of the roller, even if the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber come into contact with each other, it is possible to prevent the occurrence of seizure due to sliding.

  In the ninth invention, since the resin layer is bonded to the surface having a relatively rough surface, it is difficult to peel off.

In the tenth aspect, the cost and time required for processing the substrate can be reduced.
Moreover, since the resin layer is formed on the rough surface of the substrate that has not been polished, it is difficult to peel off from the substrate.

  In the 11th invention, since the base material is formed of ceramics or cemented carbide having a small linear expansion coefficient, it is possible to more reliably prevent the gap from being lost.

  In the twelfth invention, since the corners of the substrate are protected by the resin layer, chipping of the corners of the substrate can be prevented.

  In the thirteenth aspect, since the corners of the base material are chamfered, the corners can be more reliably prevented from being chipped.

1 is a schematic cross-sectional view of a compressor according to a first embodiment of the present invention. It is sectional drawing along the AA line of FIG. 1, Comprising: It is a figure which shows operation | movement of the piston in a cylinder. It is the figure which looked at the front head of the compressor shown in Drawing 1 from the lower part. It is a perspective view of the piston of the compressor shown in FIG. (A) is sectional drawing along the BB line of FIG. 4, (b) is sectional drawing along CC line of FIG. (A) is the elements on larger scale of FIG. 1, (b) is the elements on larger scale of FIG. It is a schematic sectional drawing of the compressor which concerns on 2nd Embodiment of this invention. It is sectional drawing along the DD line of FIG. It is a figure which shows operation | movement of the roller and vane in a cylinder in the compressor which concerns on 3rd Embodiment of this invention. It is a perspective view of the roller and vane of the compressor shown in FIG. (A) is sectional drawing along the EE line of FIG. 10, (b) is sectional drawing along the FF line of FIG. It is a figure for demonstrating a blade root part. (A) is a top view of the piston of other embodiment of this invention, (b) is sectional drawing along the GG line of (a). It is a figure for demonstrating the resin layer of the piston of other embodiment of this invention. It is a figure which shows the piston of other embodiment of this invention.

<First Embodiment>
The first embodiment of the present invention will be described below.
The present embodiment is an example in which the present invention is applied to a one-cylinder rotary compressor.
As shown in FIG. 1, the compressor 1 of the present embodiment includes a sealed casing 2, a compression mechanism 10 and a drive mechanism 6 disposed in the sealed casing 2. In FIG. 1, hatching indicating a cross section of the drive mechanism 6 is omitted. For example, the compressor 1 is used by being incorporated in a refrigeration cycle such as an air conditioner, and compresses the refrigerant (CO 2 in this embodiment) introduced from the suction pipe 3 and discharges it from the discharge pipe 4. The compressor 1 will be described below with the vertical direction in FIG.

  The hermetic casing 2 is a cylindrical container with both ends closed. An upper portion of the hermetic casing 2 has a discharge pipe 4 for discharging a compressed refrigerant and a coil of a stator 7b (to be described later) of the drive mechanism 6 as a current. Is provided with a terminal terminal 5. In FIG. 1, the wiring connecting the coil and the terminal terminal 5 is not shown. Also. A suction pipe 3 for introducing a refrigerant into the compressor 1 is provided on the side of the closed casing 2. In addition, a lubricating oil L for smoothing the operation of the sliding portion of the compression mechanism 10 is stored in the lower part of the sealed casing 2. Inside the sealed casing 2, a drive mechanism 6 and a compression mechanism 10 are arranged vertically.

  The drive mechanism 6 is provided to drive the compression mechanism 10 and includes a motor 7 serving as a drive source and a shaft 8 attached to the motor 7.

  The motor 7 includes a substantially annular stator 7b fixed to the inner peripheral surface of the hermetic casing 2, and a rotor 7a disposed on the radially inner side of the stator 7b via an air gap. . The rotor 7a has a magnet (not shown), and the stator 7b has a coil. The motor 7 rotates the rotor 7a by an electromagnetic force generated by passing a current through the coil. Further, the outer peripheral surface of the stator 7b is not in close contact with the inner peripheral surface of the hermetic casing 2 over the entire periphery. The outer peripheral surface of the stator 7b extends in the vertical direction and has a space above and below the motor 7. A plurality of recesses (not shown) to be communicated are formed side by side in the circumferential direction.

  The shaft 8 is provided to transmit the driving force of the motor 7 to the compression mechanism 10, is fixed to the inner peripheral surface of the rotor 7a, and rotates integrally with the rotor 7a. The shaft 8 has an eccentric portion 8a at a position in the compression chamber 31 described later. The eccentric portion 8 a is formed in a columnar shape, and its axis is eccentric from the rotation center of the shaft 8. A roller 41 (to be described later) of the compression mechanism 10 is mounted on the eccentric portion 8a.

  An oil supply passage 8b extending in the vertical direction is formed inside the lower half of the shaft 8. A spiral blade-shaped pump member (not shown) for sucking the lubricating oil L into the oil supply passage 8b as the shaft 8 rotates is inserted into the lower end portion of the oil supply passage 8b. Further, the shaft 8 is formed with a plurality of discharge holes 8 c for discharging the lubricating oil L in the oil supply passage 8 b to the outside of the shaft 8.

  The compression mechanism 10 is disposed on the front head (first end plate member) 20 fixed to the inner peripheral surface of the sealed casing 2, the muffler 11 disposed on the upper side of the front head 20, and the lower side of the front head 20. A cylinder 30, a piston 40 disposed inside the cylinder 30, and a rear head (second end plate member) 50 disposed below the cylinder 30. Although details will be described later, as shown in FIG. 2, the cylinder 30 is a substantially annular member, and a compression chamber 31 is formed at the center thereof. The cylinder 30 is fixed to the lower side of the front head 20 together with the rear head 50 by bolts. In FIG. 2, bolt holes formed in the cylinder 30 are omitted.

  As shown in FIGS. 1 and 3, the front head 20 is a substantially annular member, and a bearing hole 21 into which the shaft 8 is rotatably inserted is formed at the center thereof. The outer peripheral surface of the front head 20 is fixed to the inner peripheral surface of the sealed casing 2 by spot welding or the like. The lower surface of the front head 20 closes the upper end of the compression chamber 31 of the cylinder 30. The front head 20 has a discharge hole 22 for discharging the refrigerant compressed in the compression chamber 31. The discharge hole 22 is formed in the vicinity of a blade accommodating portion 33 (described later) of the cylinder 30 when viewed from the up-down direction. Although not shown, a valve mechanism that opens and closes the discharge hole 22 according to the pressure in the compression chamber 31 is attached to the upper surface of the front head 20. In addition, a plurality of oil return holes 23 are formed in the circumferential direction in the radially outer portion of the front head 20 than the cylinder 30.

  The rear head 50 is a substantially annular member, and a bearing hole 51 through which the shaft 8 is rotatably inserted is formed at the center thereof. The rear head 50 closes the lower end of the compression chamber 31 of the cylinder 30.

  The muffler 11 is provided to reduce noise when the refrigerant is discharged from the discharge hole 22 of the front head 20. The muffler 11 is attached to the upper surface of the front head 20 with bolts, and forms a muffler space M between the front head 20 and the muffler 11. Although not shown, the muffler 11 is formed with a muffler discharge hole for discharging the refrigerant in the muffler space M.

  As shown in FIGS. 1 and 2, the cylinder 30 is formed with the above-described compression chamber 31, a suction hole 32 for introducing a refrigerant into the compression chamber 31, and a blade accommodating portion 33. 2A is a cross-sectional view taken along the line AA in FIG. 1, and the discharge holes 22 of the front head 20 are not originally shown, but are shown for convenience of explanation.

  The suction hole 32 is formed so as to extend in the radial direction of the cylinder 30, and the tip of the suction pipe 3 is fitted into the end (the end opposite to the compression chamber 31).

  The blade accommodating portion 33 penetrates the cylinder 30 in the vertical direction and communicates with the compression chamber 31. The blade housing portion 33 extends in the radial direction of the compression chamber 31. The blade accommodating portion 33 is formed at a position between the suction hole 32 and the discharge hole 22 of the front head 20 when viewed from the vertical direction. A pair of bushes 34 is disposed in the blade accommodating portion 33. The pair of bushes 34 is formed in a shape in which a substantially cylindrical member is divided into half. A blade 42 is disposed between the pair of bushes 34. The pair of bushes 34 can swing in the circumferential direction in the blade housing portion 33 with the blade 42 disposed therebetween.

  As shown in FIG. 4, the piston 40 includes an annular roller 41 and a blade 42 extending radially outward from the outer peripheral surface of the roller 41. As shown in FIG. 2, the roller 41 is mounted on the outer peripheral surface of the eccentric portion 8 a so as to be relatively rotatable, and is disposed in the compression chamber 31. The blade 42 is disposed between the pair of bushes 34 disposed in the blade accommodating portion 33 so as to advance and retreat.

  As shown in FIG. 6A, the vertical length H1 of the piston 40 is slightly smaller than the vertical length H2 of the compression chamber 31, and the difference between H2 and H1 during operation is, for example, several μm. . As shown in FIGS. 6A and 6B, the outer diameter of the roller 41 is set between the outer peripheral surface of the roller 41 and the peripheral wall surface of the compression chamber 31 in a state where the roller 41 is mounted on the eccentric portion 8a. The size is sometimes such that a minute gap d1 of several μm, for example (hereinafter, this gap is referred to as a radial gap d1) is generated. Further, as shown in FIGS. 2B to 2D, in a state where the blade 42 protrudes from the blade housing portion 33 toward the compression chamber 31, the outer peripheral surface of the roller 41 and the peripheral wall surface of the compression chamber 31 The space formed between the two is partitioned by the blade 42 into a low pressure chamber 31a and a high pressure chamber 31b.

  Next, materials and manufacturing methods of the front head 20, the rear head 50, the cylinder 30, the pair of bushes 34, and the piston 40 will be described.

The front head 20 is formed by casting, sintering of metal powder, cutting, or the like, and the surface is polished. Examples of the material of the front head 20 include cast iron and sintered material. As shown in Table 1 below, the linear expansion coefficients of cast iron and sintered material are both 12 × 10 ⁻⁶ [/ ° C.]. Table 1 also shows the hardness of the cast iron and the sintered material. The linear expansion coefficient (also referred to as a linear expansion coefficient) is a ratio at which the length changes in response to an increase in temperature.

  The material and manufacturing method of the rear head 50, the cylinder 30, and the pair of bushes 34 are the same as the material and manufacturing method of the front head 20 described above. In addition, the materials and manufacturing methods of the front head 20, the rear head 50, the cylinder 30, and the pair of bushes 34 may be the same or different from each other.

  As shown in FIGS. 4 and 5, the piston 40 of the present embodiment includes a base material 43 and thin film-like resin layers 44 a to 44 d that cover the surface of the base material 43. The base material 43 is formed of a high hardness material having a smaller linear expansion coefficient than cast iron or the like. Specific examples of the high hardness material include ceramics such as alumina, zirconia, and silicon carbide, or cemented carbide such as tungsten carbide. Table 1 shows the linear expansion coefficient and hardness of alumina, zirconia, silicon carbide, and tungsten carbide. Moreover, as a resin material which comprises the resin layers 44a-44d, polyamide, an epoxy, phenol etc. are mentioned, for example.

The base material 43 substantially constitutes the outer shape of the piston 40. As shown in FIG. 5A, the outer peripheral corner portion of the portion corresponding to the roller 41 of the base material 43 has a chamfered shape. Moreover, as shown in FIG.5 (b), the corner | angular part of the part corresponded to the braid | blade 42 of the base material 43 becomes a chamfered shape.
The resin layers 44a and 44b cover the upper surface and the lower surface of the base material 43, respectively. That is, the resin layers 44a and 44b are formed on the upper end surface and the lower end surface of the piston. The resin layer 44c is formed on the outer peripheral surface of the roller 41, and the resin layer 44d is formed on both side surfaces of the blade 42 (specifically, side surfaces facing the pair of bushes 34). Therefore, the chamfered corners of the base material 43 are covered with the resin layers 44a to 44d.
Moreover, although the film thickness of the resin layers 44a-44d in the state before using the compressor 1 is 5-100 micrometers, for example, it is not limited to this thickness.

An example of the manufacturing procedure of the piston 40 will be described. First, the base material 43 is formed by sintering or casting. Thereafter, if necessary, a process for forming a hole or a process for forming a screw groove is performed. If necessary, the inner peripheral surface of the base material 43 is polished and dimensioned. The chamfered portion of the substrate 43 is preferably formed during sintering or casting, but may be formed by cutting after sintering or casting.
Next, the resin coating solution is formed on a predetermined surface of the base material 43 by applying a resin composition solution and drying it several times to form a resin coating layer. Then, the surface of the resin coating layer is polished to flatten the surface of the resin coating layer, and the dimensions of the piston 40 are determined.

  As described above, at least portions of the surface of the base material 43 where the resin layers 44a to 44d are formed are formed by sintering or casting, and then are not subjected to polishing, so the surface roughness becomes rough. ing. That is, the resin layers 44a to 44d are formed on a surface having a rough surface. In addition, arithmetic mean surface roughness Ra prescribed | regulated by JISB0601: 2001 of the part which is not grind | polished of the base material 43 is 0.3 or more, for example.

  Next, operation | movement of the compressor 1 of this embodiment is demonstrated with reference to Fig.2 (a)-FIG.2 (d). 2A shows a state in which the piston 40 is at the top dead center. FIGS. 2B to 2D show that the shaft 8 is 90 from the state of FIG. It shows a state rotated by 270 ° at 180 ° (bottom dead center).

  When the shaft 8 is rotated by driving the motor 7 while supplying the refrigerant from the suction pipe 3 to the compression chamber 31 through the suction hole 32, as shown in FIGS. 2 (a) to 2 (d), the eccentric portion The roller 41 attached to 8 a moves along the peripheral wall surface of the compression chamber 31. Thereby, the refrigerant is compressed in the compression chamber 31. Hereinafter, the process of compressing the refrigerant will be described in detail.

  When the eccentric portion 8a rotates in the direction of the arrow in the figure from the state of FIG. 2A, a space formed by the outer peripheral surface of the roller 41 and the peripheral wall surface of the compression chamber 31 is formed as shown in FIG. The chamber is divided into a low pressure chamber 31a and a high pressure chamber 31b. When the eccentric portion 8a further rotates, the volume of the low pressure chamber 31a increases as shown in FIGS. 2 (b) to 2 (d). Therefore, the refrigerant enters the low pressure chamber 31a from the suction pipe 3 through the suction hole 32. Is sucked in. At the same time, since the volume of the high pressure chamber 31b is reduced, the refrigerant is compressed in the high pressure chamber 31b.

  Then, when the pressure in the high pressure chamber 31b becomes equal to or higher than a predetermined pressure, the valve mechanism provided in the front head 20 opens, and the refrigerant in the high pressure chamber 31b passes through the discharge hole 22 and the muffler space M Discharged. Thereafter, the state returns to the state of FIG. 2A, and the discharge of the refrigerant from the high pressure chamber 31b is completed. By repeating this process, the refrigerant supplied from the suction pipe 3 to the compression chamber 31 is continuously compressed and discharged.

  The refrigerant discharged into the muffler space M is discharged out of the compression mechanism 10 through a muffler discharge hole (not shown) of the muffler 11. The refrigerant discharged from the compression mechanism 10 passes through an air gap between the stator 7b and the rotor 7a, and is finally discharged out of the sealed casing 2 from the discharge pipe 4.

  At this time, a part of the lubricating oil L supplied into the compression chamber 31 from the discharge hole 8c of the shaft 8 is discharged into the muffler space M from the discharge hole 22 together with the refrigerant, and then the muffler discharge hole (not shown) of the muffler 11. ) To the outside of the compression mechanism 10. A part of the lubricating oil L discharged to the outside of the compression mechanism 10 is returned to the storage portion at the lower part of the sealed casing 2 through the oil return hole 23 of the front head 20. Further, another part of the lubricating oil L discharged to the outside of the compression mechanism 10 is formed on the outer peripheral surface of the stator 7b after passing through the air gap between the stator 7b and the rotor 7a together with the refrigerant. Between the recessed portion (not shown) and the inner peripheral surface of the sealed casing 2, and through the oil return hole 23 of the front head 20, is returned to the storage section at the lower portion of the sealed casing 2.

  As described above, the vertical length of the piston 40 is set slightly smaller than the vertical length of the compression chamber 31. Therefore, during normal operation of the compressor 1, as shown in FIG. 6A, a minute gap between the upper end surface of the piston 40 and the front head 20 and between the lower end surface of the piston 40 and the rear head 50. The lubricating oil L discharged from the discharge hole 8c of the shaft 8 is held in D1 and D2 (hereinafter, these gaps are referred to as axial gaps D1 and D2). By providing the axial gaps D1 and D2, seizure between the upper end surface of the piston 40 and the front head 20 and the lower end surface of the piston 40 and the rear head 50 is prevented.

  Further, as described above, the outer diameter of the roller 41 is such that the outer peripheral surface of the roller 41 forms a minute radial gap d1 between the outer peripheral surface of the roller 41 and the peripheral wall surface of the compression chamber 31 when mounted on the eccentric portion 8a. It is a big size. Therefore, during the normal operation of the compressor 1, as shown in FIG. 6A, the lubricating oil L discharged from the discharge hole 8c of the shaft 8 is held in the radial gap d1. By providing the radial gap d1, seizure between the outer peripheral surface of the roller 41 and the peripheral wall surface of the compression chamber 31 is prevented, and the shaft 8 is misaligned when the roller 41 contacts the peripheral wall surface of the compression chamber 31. Is preventing.

  In this embodiment, since the thermal expansion coefficient of the base material 43 constituting the piston 40 is smaller than that of cast iron or the like, even if the temperature of the piston 40 is higher than the temperature of the cylinder 30, It is possible to prevent the thermal expansion amount from becoming larger than the thermal expansion amount of the cylinder 30. Accordingly, it is possible to prevent the axial gaps D1 and D2 and the radial gap d1 from being lost.

  Further, when the piston is composed only of a high hardness material such as ceramics or cemented carbide, surface processing (for example, polishing) is difficult, but the piston 40 of the present embodiment is made of the base material 43 made of a high hardness material. Since the surface is covered with the resin layers 44 to 44d, the surface of the piston 40 (except for the inner peripheral surface of the roller 41) can be processed by simply processing the resin layers 44 to 44d. It can be carried out.

Further, as described above, the surface of the base material 43 (at least the portion covered with the resin layers 44a to 44d) is not polished. Therefore, the cost and time required for processing the base material 43 can be reduced.
In addition, since the resin layers 44a to 44d are formed on the surface of the base material 43 that is not polished, the surface roughness is rough (specifically, the arithmetic average surface roughness Ra is, for example, 0.3 or more). It is difficult to peel off from the base material 43.

Further, ceramics and cemented carbide, which are examples of the material of the base material 43, have low toughness and are easily chipped, but correspond to the outer peripheral corner portion of the base material 43 corresponding to the roller 41 and the blade 42. Since the corner portion is covered and protected by the resin layers 44a to 44d, chipping of the corner portion can be prevented.
Furthermore, since the corners covered with the resin layers 44a to 44d are formed in a chamfered shape, chipping of the corners can be more reliably prevented.

  Further, the resin layers 44a to 44d swell by absorbing the lubricating oil L and the refrigerant. Therefore, when the swelling amount increases, the axial gaps D1 and D2 or the radial gap d1 may disappear. In this case, seizure can be prevented from occurring due to the slidability of the resin layers 44a to 44c.

Second Embodiment
Next, a second embodiment of the present invention will be described.
The present embodiment is an example in which the present invention is applied to a two-cylinder rotary compressor.
As shown in FIG. 7, the compressor 101 of this embodiment differs in the structure of the shaft 108 and the compression mechanism 110 from the said 1st Embodiment. Further, in the compressor 101 of the present embodiment, the two suction pipes 3 are provided side by side on the side of the sealed casing 2. Since other configurations are the same as those of the first embodiment, the same reference numerals are used and the description thereof is omitted as appropriate.

  The shaft 108 has two eccentric portions 108a and 108d. The shaft centers of the two eccentric portions 108a and 108d are shifted by 180 ° about the rotation axis of the shaft 108. Moreover, the shaft 108 has the oil supply path 108b and the some discharge hole 108c similarly to the shaft 8 of the said 1st Embodiment.

  The compression mechanism 110 includes a front muffler 111, a front head 120, a cylinder 130 and a piston 140, a middle plate 150, a cylinder 160 and a piston 170 in order from the top to the bottom along the axial direction of the shaft 108. A rear head 180 and a rear muffler 112 are provided. The front head 120 and the middle plate 150 are arranged at the upper and lower ends of the piston 140 and correspond to the first end plate member and the second end plate member of the present invention. The middle plate 150 and the rear head 180 are disposed at the upper and lower ends of the piston 170 and correspond to the first end plate member and the second end plate member of the present invention.

  The front muffler 111 has the same configuration as the muffler 11 of the first embodiment, and forms a muffler space M1 between the front muffler 111 and the front head 120.

  The front head 120 has a bearing hole 121, a discharge hole 122 (see FIG. 8), and an oil return hole 123. Further, the front head 120 has a through hole (not shown) penetrating in the vertical direction. The through hole constitutes a part of a flow path for discharging the refrigerant in the muffler space M2 formed by the rear head 180 and the rear muffler 112 to the muffler space M1. The front head 120 has the same configuration as the front head 20 of the first embodiment, except that the front head 120 has the through hole.

  As shown in FIG. 8, the cylinder 130 is formed with a compression chamber 131, a suction hole 132, and a blade accommodating portion 133. Further, a through hole 135 for discharging a refrigerant in the muffler space M2 described later to the muffler space M1 is formed in the outer peripheral side portion of the compression chamber 131 in the cylinder 130. The cylinder 130 has the same configuration as the cylinder 30 of the first embodiment except that the cylinder 130 has the through hole 135.

  The piston 140 has the same configuration as the piston 40 of the first embodiment, and includes a roller 41 and a blade 42. The roller 41 is rotatably mounted on the outer peripheral surface of the eccentric portion 108 a, and the blade 42 is disposed between the pair of bushes 34 disposed in the blade accommodating portion 133 of the cylinder 130 so as to advance and retreat. Moreover, the piston 140 is comprised from the base material 43 and resin layer 44a-44d similarly to the piston 40 of the said 1st Embodiment.

  The middle plate 150 is an annular plate member that is disposed between the cylinder 130 and the cylinder 160 and closes the lower end of the compression chamber 131 of the cylinder 130 and closes the upper end of the compression chamber 131 of the cylinder 160. ing. Further, the middle plate 150 is formed with a through hole (not shown) for discharging a refrigerant in the muffler space M2 described later to the muffler space M1. The middle plate 150 is manufactured by the same material and manufacturing method as the front head 20 of the first embodiment.

  The cylinder 160 has the same configuration as the cylinder 130 described above, and includes a compression chamber 161, a suction hole 162, a blade accommodating portion (not shown) in which a pair of bushes 34 are arranged, and a through hole (not shown). Have

  The piston 170 has the same configuration as the piston 40 of the first embodiment, and includes a roller 41 and a blade 42. The roller 41 is rotatably mounted on the outer peripheral surface of the eccentric portion 108d, and the blade 42 is disposed between a pair of bushes 34 disposed in a blade accommodating portion (not shown) of the cylinder 160 so as to be able to advance and retreat. Yes. Moreover, the piston 170 is comprised from the base material 43 and resin layer 44a-44d similarly to the piston 40 of the said 1st Embodiment.

  The rear head 180 is disposed below the cylinder 160 and closes the lower end of the compression chamber 131 of the cylinder 160. The rear head 180 is a substantially annular member, and a bearing hole 181 through which the shaft 108 is rotatably inserted is formed at the center thereof. Further, the rear head 180 is formed with a discharge hole (not shown) for discharging the refrigerant compressed in the compression chamber 161 of the cylinder 160 to the muffler space M2 formed between the rear head 180 and the rear muffler 112. Yes. Further, the rear head 180 is formed with a through hole (not shown) for discharging the refrigerant in the muffler space M2 to the muffler space M1. A valve mechanism (not shown) that opens and closes the discharge hole according to the pressure in the compression chamber 131 is attached to the lower surface of the rear head 180. The rear head 180 is manufactured by the same material and manufacturing method as the front head 20 of the first embodiment.

  The rear muffler 112 is provided to reduce noise when the refrigerant is discharged from the discharge hole (not shown) of the rear head 180. The rear muffler 112 is attached to the lower surface of the rear head 180 with bolts, and forms a muffler space M2 between the rear muffler 112 and the rear head 180. The muffler space M2 communicates with the muffler space M1 through through holes formed in the rear head 180, the cylinder 160, the middle plate 150, the cylinder 130, and the front head 120, respectively.

The operation of the compressor 101 of this embodiment will be described.
When the shaft 108 is rotated by driving the motor 7 while supplying the refrigerant from the suction holes 132 and 162 to the compression chambers 131 and 161, the roller 41 of the piston 140 attached to the eccentric portion 108 a Move along. Thereby, the refrigerant is compressed in the compression chamber 131. In parallel with this, the roller 41 of the piston 170 attached to the eccentric portion 108 d moves along the peripheral wall surface of the compression chamber 161. As a result, the refrigerant is compressed in the compression chamber 161.

When the pressure in the compression chamber 131 becomes equal to or higher than a predetermined pressure, the valve mechanism provided in the front head 120 is opened, and the refrigerant in the compression chamber 131 flows from the discharge hole 22 of the front head 120 through the muffler space M1. Discharged.
Further, when the pressure in the compression chamber 161 becomes equal to or higher than a predetermined pressure, the valve mechanism provided in the rear head 180 is opened, and the refrigerant in the compression chamber 161 is discharged from a discharge hole (not shown) of the rear head 180. It is discharged into the muffler space M2. The refrigerant discharged to the muffler space M2 is discharged to the muffler space M1 through through holes formed in the rear head 180, the cylinder 160, the middle plate 150, the cylinder 130, and the front head 120, respectively.

  The refrigerant discharged into the muffler space M1 is discharged out of the compression mechanism 110 through a muffler discharge hole (not shown) of the front muffler 111, and then passes through an air gap between the stator 7b and the rotor 7a. Thereafter, it is finally discharged from the discharge pipe 4 to the outside of the sealed casing 2.

  In the present embodiment, as in the first embodiment, the pistons 140 and 170 have a base material 43 made of a high-hardness material having a smaller linear expansion coefficient than cast iron and the like, and a resin layer that covers the surface of the base material 43. 44a to 44d. Therefore, the same effect as the first embodiment can be obtained.

<Third Embodiment>
Next, a third embodiment of the present invention will be described.
The compressor of the present embodiment is different from the first embodiment in the configuration of the compression mechanism 210. Since other configurations are the same as those of the first embodiment, the same reference numerals are used and the description thereof is omitted as appropriate.

  As shown in FIG. 9, the compression mechanism 210 differs in the structure of the member arrange | positioned inside the cylinder 230 and the cylinder 230, and the other structure is the same as that of the said 1st Embodiment.

  The cylinder 230 has a compression chamber 231 and a suction hole 232. Further, the cylinder 230 has a vane accommodating portion 233 instead of the blade accommodating portion 33 of the first embodiment, and other configurations are the same as those of the cylinder 30 of the first embodiment. The vane accommodating portion 233 passes through the cylinder 230 in the vertical direction and communicates with the compression chamber 231. Further, the vane accommodating portion 233 extends in the radial direction of the compression chamber 231.

  An annular roller 241 is disposed inside the compression chamber 231. The roller 241 is disposed in the compression chamber 231 in a state in which the roller 241 is mounted on the outer peripheral surface of the eccentric portion 8a so as to be relatively rotatable. The vertical length of the roller 241 is the same as the vertical length H1 of the piston 40 of the first embodiment. Further, the outer diameter of the roller 241 is the same as the outer diameter of the roller 41 of the piston 40 of the first embodiment.

  A vane 244 is disposed inside the vane housing portion 233. As shown in FIG. 10, the vane 244 is a flat plate-like member, and the vertical length thereof is the same as the vertical length of the roller 241. The tip of the vane 244 on the center side of the compression chamber 231 (lower tip in FIG. 9) is formed in a tapered shape as viewed from above. Further, the vane 244 is urged by an urging spring 247 provided in the vane housing portion 233, and the distal end portion on the compression chamber 231 side is pressed against the outer peripheral surface of the roller 241. Therefore, as shown in FIGS. 9A to 9D, when the roller 241 moves along the peripheral wall surface of the compression chamber 231 as the shaft 8 rotates, the vane 244 is moved in the vane accommodating portion 233. Then, it moves forward and backward along the radial direction of the compression chamber 231. 9B to 9D, when the vane 244 protrudes from the vane housing portion 233 to the compression chamber 231 side, the outer peripheral surface of the roller 241 and the peripheral wall surface of the compression chamber 231 The space formed between is divided into a low pressure chamber 231a and a high pressure chamber 231b by a vane 244.

  As shown in FIGS. 10 and 11A, the roller 241 includes a base material 242 and thin film resin layers 243 a to 243 c that cover the surface of the base material 242. As shown in FIGS. 10 and 11B, the vane 244 includes a base material 245 and thin film resin layers 246a to 246c that cover the surface of the base material 245. The materials of the base materials 242 and 245 are the same as those of the base material 43 of the first embodiment, and the materials and film thicknesses of the resin layers 243a to 243c and 246a to 246c are the resin layers 44a to 44 of the piston 40 of the first embodiment. It is the same as 44d.

  As shown in FIGS. 11A and 11B, the outer shapes of the base materials 242 and 245 substantially constitute the outer shapes of the roller 241 and the vane 244, respectively. Further, the outer peripheral corner portion of the base material 242 and the corner portion of the base material 245 each have a chamfered shape.

As shown in FIG. 11A, the resin layers 243a and 243b cover the upper surface and the lower surface of the substrate 242, respectively. That is, the resin layers 243 a and 243 b are formed on the upper end surface and the lower end surface of the roller 241. Further, the resin layer 243 c is formed on the outer peripheral surface of the roller 241.
11B, the resin layers 246a and 246b are formed on the upper end surface and the lower end surface of the vane 244, and the resin layer 246c is formed on the side surface of the vane 244 (a surface other than the upper and lower end surfaces). Is formed. The materials and thicknesses of the resin layers 243a to 243c, 246a to 246c are the same as those of the resin layers 44a to 44d of the piston 40 of the first embodiment.
The manufacturing procedure of the roller 241 and the vane 244 is the same as the manufacturing procedure of the piston 40 described in the first embodiment.

Next, the operation of the compressor of this embodiment will be described.
FIG. 9A shows a state where the roller 241 is at the top dead center, and FIGS. 9B to 9D show that the shaft 8 is 90 from the state of FIG. It shows a state rotated by 270 ° at 180 ° (bottom dead center).

  When the shaft 8 is rotated by driving the motor 7 while supplying the refrigerant from the suction pipe 3 to the compression chamber 231 through the suction hole 232, as shown in FIGS. 9A to 9D, the eccentric portion The roller 241 attached to 8 a moves along the peripheral wall surface of the compression chamber 231. Thereby, the refrigerant is compressed in the compression chamber 231. Hereinafter, the process of compressing the refrigerant will be described in detail.

  When the eccentric portion 8a rotates in the direction of the arrow in the drawing from the state of FIG. 9A, a space formed by the outer peripheral surface of the roller 241 and the peripheral wall surface of the compression chamber 231 is formed as shown in FIG. 9B. The chamber is divided into a low pressure chamber 231a and a high pressure chamber 231b. When the eccentric portion 8a further rotates, the volume of the low-pressure chamber 231a increases as shown in FIGS. 9B to 9D, so that the refrigerant enters the low-pressure chamber 231a from the suction pipe 3 through the suction hole 232. Is sucked in. At the same time, since the volume of the high pressure chamber 231b is reduced, the refrigerant is compressed in the high pressure chamber 231b.

  When the pressure in the high-pressure chamber 231b becomes equal to or higher than a predetermined pressure, the valve mechanism provided in the front head 20 is opened, and the refrigerant in the high-pressure chamber 231b passes through the discharge hole 22 to the muffler space M. Discharged. The refrigerant discharged into the muffler space M passes through the same path as the compressor 1 of the first embodiment, and is finally discharged out of the sealed casing 2 from the discharge pipe 4.

  In the present embodiment, the roller 241 and the vane 244 respectively cover a base material made of a high-hardness material having a linear expansion coefficient smaller than that of cast iron and the like, like the piston 40 of the first embodiment. And a resin layer. Therefore, the same effect as the first embodiment can be obtained.

  As mentioned above, although embodiment of this invention was described, it should be thought that the specific structure of this invention is not limited to the said 1st-3rd embodiment. The scope of the present invention is shown not only by the description of the above-described embodiment but also by the scope of claims for patent, and further includes meanings equivalent to the scope of claims for patent and all modifications within the scope. Note that the following modifications can be implemented in combination as appropriate.

The base portions 43 of the pistons 40, 140, and 170 of the first and second embodiments are chamfered at the corners, but are not necessarily chamfered.
The same applies to the corners of the substrates 242 and 245 of the roller 241 and the vane 244 of the third embodiment.

  In the first to third embodiments, portions of the surfaces of the base materials 43, 242 and 245 that are covered with the resin layer are not polished, but are polished to remove, for example, an oxide film. Processing may be given.

  In the first and second embodiments, the thicknesses of the resin layers 44a to 44d of the pistons 40, 140, and 170 are constant, but may not be constant.

  For example, the thickness of the resin layer on the upper and lower end surfaces of the roller may be gradually reduced from the low pressure chamber side to the high pressure chamber side, with the root portion of the blade (the portion indicated by a thick line in FIG. 12) as a boundary. . That is, the thickness of the resin layer on the upper and lower end surfaces of the roller excluding the radially inner portion of the blade root portion is from the low pressure chamber side end portion of the blade root portion to the high pressure chamber side end portion of the blade root portion. It may be gradually thinner toward In the case of this modified form, the thickness of the resin layer in the radially inner region of the root portion of the blade (indicated by hatching in FIG. 12) is equal to or less than the thickness of the low pressure chamber side end portion of the root portion of the blade, and The thickness of the base portion of the blade is equal to or greater than the thickness of the end portion on the high pressure chamber side, and the thickness of the boundary portion is changed gradually.

  Further, for example, in the resin layer on the upper and lower end surfaces of the roller, the thickness of the half region on the high pressure chamber side from the root portion of the blade is thinner than the thickness of the half region on the low pressure chamber side from the root portion of the blade. Also good. Of the resin layers on the upper and lower end surfaces of the roller, the region on the high pressure chamber side from the root portion of the blade is the region on the radially inner side of the root portion of the blade in the resin layer on the upper and lower end surfaces of the roller (FIG. 12). This is the area on the high-pressure chamber side when the area excluding (indicated by middle hatching) is halved. In the case of this modified form, the thickness of the resin layer in the radially inner region of the blade root portion (indicated by hatching in FIG. 12) is equal to or less than the thickness of the half region on the low pressure chamber side from the blade root portion, and The thickness should be equal to or greater than the thickness of the half region on the high pressure chamber side from the root of the blade.

  Further, for example, in the resin layer on the upper and lower end surfaces of the roller, the thickness of a part of the half region on the high pressure chamber side from the root portion of the blade is thinner than the minimum thickness of the half region on the low pressure chamber side from the root portion of the blade. May be. In this case, the thickness of the remaining resin layer in the half region on the high pressure chamber side is the same as the minimum thickness of the half region on the low pressure chamber side from the root of the blade. Further, the thickness of the resin layer in the radially inner region of the blade root portion (indicated by hatching in FIG. 12) is equal to or less than the thickness of the half region on the low-pressure chamber side from the blade root portion, and the blade root portion. More than the thickness of the half region on the higher pressure chamber side.

  The portion in contact with the high pressure chamber to which the refrigerant is compressed is exposed to a higher temperature than the low pressure chamber side to which the refrigerant is supplied. According to these configurations, the thickness of the resin layer during thermal expansion can be made uniform. Therefore, it is possible to prevent only the high pressure chamber side portion of the roller end surface from coming into contact with the front head and the rear head.

Further, for example, the thickness may be changed like the resin layers 344a and 344b on the upper and lower end surfaces of the piston 340 shown in FIG. Resin layer 344a is composed of a thin film portion 344a ₁ and the thick portion 344a ₂ Prefecture, the thickness of the thin portion 344a ₁ also e.g. 3~50μm thinner than the thickness of the thick portion 344a _2, a thin film portion 344a ₁ the thickness of the boundary portion between the thick portion 344a ₂ are slowly changing. The thin film portion 344a ₁ is formed in an approximately half region of the upper end surface of the roller 341, and the thick film portion 344a ₂ is formed in the remaining region of the upper end surface of the piston 340 and the upper end surface of the blade 342. . The formation range of the thin film portion 344a ₁ will be described in detail below. The radial gap d1 changes periodically. When the radial gap d1 is minimized, the portion of the outer peripheral surface of the roller 341 that defines the high pressure chamber 31b is denoted by W1. The thin film portion 344 a ₁ is formed in a portion S 1 corresponding to the portion W 1 on the outer peripheral surface of the roller 341 on the upper end surface of the roller 341.
13B, the resin layer 344b on the lower end surface of the piston 340 is formed on the back side of the thin film part 344b ₁ formed on the back side of the thin film part 344a _{1 and on} the back side of the thick film part 344a ₂ . The thick film portion 344b ₂ is included.
Since the left half of the piston 340 in FIG. 13 is heated by the high-temperature refrigerant in the high-pressure chamber 31b, the temperature of the thin film portion 344a ₁ (344b ₁ ) is that of the thick film portion 344a ₂ (344b ₂ ). It becomes higher than the temperature. By making the thickness of the thin film portion 344a ₁ (344b ₁ ) thinner than that of the thick film portion 344a ₂ (344b ₂ ), the thickness of the thin film portion 344a ₁ (344b ₁ ) at the time of thermal expansion is changed to the thick film portion 344a ₂ (344b ₂ ). The thickness at the time of thermal expansion of ₂ ) can be made substantially the same. Therefore, the axial gap can be made uniform.

When the thicknesses of the resin layers on the upper and lower ends of the piston are made different, the thickness of the portion S1 corresponding to the portion W1 on the outer peripheral surface of the roller is thinner than the thickness of the portion S2 corresponding to a later-described portion W1 on the outer peripheral surface of the roller. Is preferred. In this case, the thickness of portions other than the portions S1 and S2 in the resin layer on the upper and lower end surfaces of the piston may be equal to or smaller than the thickness of the portion S2.
In FIG. 14, a straight line L <b> 1 extending from the axial center of the compression chamber 31 toward the axial center side of the roller 41 is the downstream end of the suction hole 32 in the moving direction of the roller 41 (clockwise in FIG. 14). A state passing through P1 is shown. At this time, a portion of the outer peripheral surface of the roller 41 that defines the low-pressure chamber 31a is denoted by W2. Since the portion W2 is cooled by the refrigerant supplied from the suction hole 32, it is at a low temperature. Therefore, in the resin layer on the upper and lower end surfaces of the roller 41, the portion S2 corresponding to the portion W2 has a small amount of thermal expansion.
Therefore, by making the thickness of the resin layer portion S1 on the upper and lower end surfaces of the piston 40 smaller than the thickness of the portion S2, the thickness of the resin layer at the time of thermal expansion can be made uniform.

  In the piston of the above embodiment and this modified form, the outer peripheral shape of the roller 41 is circular. However, like the piston 440 shown in FIG. 15, the suction hole extends from the proximal end portion of the blade 442 to the outer peripheral surface of the roller 441. A notch 445 extending to the 32 side (the right side in FIG. 15) may be formed. In FIG. 15, as in FIG. 14, a straight line L <b> 1 extending from the axial center of the compression chamber 31 toward the axial center side of the roller 441 is the moving direction of the roller 441 in the suction hole 32 (clockwise in FIG. 15). A state of passing through the downstream end P1 is shown. Depending on the length of the notch, as shown in FIG. 15, the portion W402 that defines the low-pressure chamber 31a on the outer peripheral surface of the roller 141 has a slightly circumferential length longer than the portion W2 shown in FIGS. become longer.

In the first and second embodiments, the resin layer is provided on a surface other than the inner peripheral surface of the roller 41 of the pistons 40, 140, and 170. However, the resin layer may be provided on the inner peripheral surface of the roller 41 as well. Good.
The same applies to the inner peripheral surface of the roller 241 of the third embodiment.

In the first and second embodiments, the resin layer 44a is provided on the entire upper end surface of the piston 40, 140, 170, but may be provided only on a part of the upper end surface of the piston. For example, the resin layer 44 a may be provided only on the upper end surface of the roller 41.
Similarly, the resin layers 44b to 44d of the first and second embodiments and the resin layers 243a to 243c and 246a to 246c of the third embodiment may be provided only on a part rather than the entire surface.

In the first and second embodiments, the four resin layers 44a to 44d are provided on the pistons 40, 140, and 170, but all of the four resin layers may not necessarily be provided. For example, only the resin layers 44a and 44b may be provided.
The same applies to the resin layers 243a to 243c of the roller 241 of the third embodiment. The same applies to the resin layers 246a to 246c of the vane 244 of the third embodiment.

  In the third embodiment, both the roller 241 and the vane 244 are composed of a base material and a resin layer made of a high-hardness material, but only one of them is a base material and a resin layer made of a high-hardness material. It may be comprised. In this case, the other may be formed of only a high-hardness material, or a metal material similar to the conventional one, or may be composed of a base material and a resin layer made of the same metal material as the conventional one.

  A resin layer may be provided on the surfaces of the cylinders 30, 130, 160, 230, the front heads 20, 120, the rear heads 50, 180, the pair of bushes 34, or the middle plate 150.

In the first and second embodiments, the pair of bushes 34 are made of cast iron or the like. However, the base material made of a high-hardness material similar to the base material 43 and the entire surface or one surface of the base material. It may be constituted by a resin layer that covers a portion (for example, upper and lower end surfaces). In this case, the manufacturing procedure of the pair of bushes is the same as the manufacturing procedure of the piston described in the first embodiment. Moreover, it is preferable that the corner | angular part of a base material is chamfered.
According to this configuration, it is possible to prevent the gap between the upper end surface (lower end surface) of the pair of bushes and the front head (rear head or middle plate) from being lost due to thermal expansion of the pair of bushes. Furthermore, the effect similar to the effect by having comprised the piston 40 by the base material 43 and resin layer 44a-44d described in the said 1st Embodiment is acquired.
In the case of this modification, the pistons 40, 140, and 170 may be formed of cast iron that is the same as the front head 20 or the like.

  The cylinders 30, 130, 160, 230, the front heads 20, 120, the rear heads 50, 180, or the middle plate 150 may be formed of a high hardness material similar to the base material 43, and a base made of a high hardness material. You may be comprised with the material and the resin layer which coat | covers the surface of this base material.

  In the first to third embodiments, the compression mechanism is supported by the outer peripheral portion of the front heads 20 and 120 being fixed to the inner peripheral surface of the sealed casing 2, but the cylinders 30, 130, 160, middle The structure supported by fixing the outer peripheral part of the plate 150 or the rear heads 50 and 180 to the inner peripheral surface of the airtight casing 2 may be sufficient.

  In the third embodiment, the compression mechanism including the roller 241 and the vane 244 is applied to a one-cylinder rotary compressor. However, the compression mechanism may be applied to a two-cylinder rotary compressor.

  By utilizing the present invention, it is possible to prevent the gap from being lost due to the difference in thermal expansion between the roller and the cylinder and to easily perform the surface processing of the roller and the like.

1, 101 Compressor 20, 120 Front head (first end plate member)
30, 130, 160 Cylinder 31, 131, 161 Compression chamber 33, 133 Blade housing groove (blade housing portion)
34 Pair of bushes 40, 140, 170 Piston 41 Roller 42 Blade 43 Base material 44a-44d Resin layer 50, 180 Rear head (second end plate member)
150 middle plate (first end plate member, second end plate member)
230 Cylinder 231 Compression chamber 233 Vane housing groove (vane housing portion)
241 Roller 242 Base material 243a to 243c Resin layer 244 Vane 245 Base material 246a to 246c Resin layer

Claims (13)

A cylinder having a compression chamber and a blade accommodating portion communicating with the compression chamber;
A first end plate member and a second end plate member disposed at both axial ends of the cylinder;
A piston disposed inside the compression chamber and the blade housing;
A pair of bushes disposed inside the blade accommodating portion,
The piston includes an annular roller disposed in the compression chamber and a blade extending from the outer peripheral surface of the roller and disposed between the pair of bushes disposed in the blade accommodating portion so as to be able to advance and retreat. And
At least one of the piston and the pair of bushes is
A base material formed of a high-hardness material having a linear expansion coefficient smaller than 12 × 10 ⁻⁶ [/ ° C.],
A resin layer covering at least a portion of the surface of the substrate;
The compressor characterized by having.   2. The compressor according to claim 1, wherein the resin layer is formed on at least one of an axial end surface of the piston and an outer peripheral surface of the roller. The cylinder further has a suction hole that opens to a peripheral wall surface of the compression chamber and introduces a refrigerant into the compression chamber;
The piston divides the compression chamber into a high pressure chamber and a low pressure chamber together with the blade while the roller moves along the peripheral wall surface of the compression chamber,
The resin layer is formed on the entire surface of the portion serving as the axial end surface of the roller,
The thickness of the resin layer in a part of the high pressure chamber side half from the root portion of the blade in the axial end surface of the roller is a region in the low pressure chamber side half from the root portion of the blade in the axial end surface of the roller. And the thickness of the resin layer in the remaining portion of the half portion on the high pressure chamber side from the root portion of the blade on the axial end surface of the roller is the blade on the axial end surface of the roller. 3. The compressor according to claim 1, wherein the compressor has a thickness equal to or less than a minimum thickness of a region on the low pressure chamber side half from a root portion of the compressor.   The thickness of the resin layer in the region on the high pressure chamber side half from the root portion of the blade on the axial end surface of the roller is the thickness in the region on the low pressure chamber side half from the root portion of the blade in the axial end surface of the roller. The compressor according to claim 3, wherein the compressor is thinner than the thickness of the resin layer.   Of the resin layer formed on the entire surface of the portion serving as the axial end surface of the roller, the portion excluding the radially inner portion of the root portion of the blade is from the low pressure chamber side end portion of the root portion of the blade. The compressor according to claim 3, wherein the thickness of the root portion of the blade gradually decreases toward the end portion on the high pressure chamber side. The cylinder further has a suction hole that opens to a peripheral wall surface of the compression chamber and introduces a refrigerant into the compression chamber;
The piston divides the compression chamber into a high pressure chamber and a low pressure chamber together with the blade while the roller moves along the peripheral wall surface of the compression chamber,
The resin layer is formed on the entire surface of the portion serving as the axial end surface of the roller,
In the axial end surface of the roller, when a gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber is minimized, a portion of the outer peripheral surface of the roller corresponding to a portion defining the high pressure chamber The resin layer has a thickness of
On the axial end surface of the roller, a straight line extending from the axial center of the compression chamber toward the axial center side of the roller as viewed from the axial direction of the compression chamber is on the downstream side in the moving direction of the roller in the suction hole. 3. The compressor according to claim 1, wherein when passing through the end portion, the thickness of the resin layer corresponding to the portion defining the low-pressure chamber in the outer peripheral surface of the roller is thinner. A cylinder having a compression chamber and a vane accommodating portion communicating with the compression chamber;
A first end plate member and a second end plate member disposed at both axial ends of the cylinder;
An annular roller disposed inside the compression chamber;
A vane having a tip pressed against the outer peripheral surface of the roller and arranged to be able to advance and retreat inside the vane housing portion;
At least one of the roller and the vane is
A base material formed of a high-hardness material having a linear expansion coefficient smaller than 12 × 10 ⁻⁶ [/ ° C.],
A resin layer covering at least a portion of the surface of the substrate;
The compressor characterized by having.   8. The compressor according to claim 7, wherein the resin layer is formed on at least one whole surface of a portion that becomes an axial end surface of the roller and an outer peripheral surface of the roller.   The compressor according to any one of claims 1 to 8, wherein a portion of the surface of the base material that is covered with the resin layer has an arithmetic average surface roughness Ra of 0.3 or more.   10. The compressor according to claim 1, wherein a portion of the surface of the base material that is covered with the resin layer is not polished. 10.   The compressor according to claim 1, wherein the high-hardness material is ceramic or cemented carbide.   The compressor according to claim 1, wherein the resin layer covers corners of the base material.   The compressor according to claim 12, wherein the corner portion of the base material has a chamfered shape.

Images