JP3213891U - Swash plate compressor - Google Patents

Abstract

A sliding contact portion between an outer peripheral surface of a swash plate and a rotation preventing portion of a piston reduces wear due to a file effect and increases the amount of oil retained on the outer periphery of the swash plate. Provided is a swash plate compressor capable of improving durability and reliability at a sliding contact portion. In a swash plate type compressor in which rotation of a piston is prevented by forming a rotation preventing portion capable of sliding contact with an outer peripheral surface of a swash plate in a mooring recess of the piston, the outer peripheral surface of the swash plate is A plurality of grooves 30 that are inclined in the same direction as the swash plate 20 with respect to a plane β orthogonal to the shaft axis α of the shaft are provided. A plurality of grooves 30 are formed in parallel with the inclined surface 20 b of the swash plate 20. It is possible to increase the amount of oil retained by the groove 30 and reduce the file effect between the rotation preventing portion. [Selection] Figure 3

Description

  The present invention relates to a swash plate compressor in which a slope outer edge portion of a swash plate is moored in a mooring recess of a piston, and the piston is reciprocated as the swash plate rotates. The present invention relates to a swash plate type compressor provided with a rotation blocking portion for slidingly contacting and preventing rotation of a piston.

  In a swash plate type piston compressor used in a car air conditioner, durability at each sliding portion is required, but the sliding between the outer peripheral surface of the swash plate and the rotation preventing portion provided in the mooring recess of the piston is required. The contact part is one of them. In passenger car compressors, the contact between the outer peripheral surface of the swash plate and the rotation-preventing portion is relatively weak, so there is no particular problem, but for heavy duty mounted on large vehicles such as buses and trucks. In such compressors, the contact between the outer peripheral surface of the swash plate and the rotation preventing portion is strong, and further durability (reduction of wear) is required, and improvement of the structure of the portion is required.

  Therefore, in the prior art, a large number of circumferential grooves that obliquely intersect the slope of the swash plate (shoe sliding surface of the swash plate) on the outer peripheral surface of the swash plate (in the embodiment, the rotating shaft on which the swash plate is fixed) This circumferential direction groove is shifted from one side of the rotation preventing portion of the piston to the other side with the rotation of the swash plate. A configuration has been proposed in which the lubricant between the rotation preventing portions is lubricated and cooled with the lubricating oil held in the grooves (see Patent Document 1).

Japanese Utility Model Publication No. 5-24974

  However, in the conventional configuration, the circumferential groove is formed so as to be substantially perpendicular to the axis of the rotation shaft and is oblique to the slope of the swash plate. It is substantially equal to an angle (an inclination angle of the swash plate with respect to a plane perpendicular to the axis of the rotation axis). For this reason, when the outer peripheral surface of the swash plate is in sliding contact with the rotation prevention portion of the piston, the file effect at the edge portion of the circumferential groove is increased, and the wear of the outer peripheral surface of the swash plate and the rotation prevention portion of the piston is increased. Inconvenience occurs. In addition, when the oblique angle with respect to the slope of the circumferential groove is increased, it becomes impossible to increase the length of the circumferential groove formed on the outer peripheral surface of the swash plate, and the oil retained in the groove is moved. Since the length is shortened, the amount of oil held in the groove (oil holding amount) is reduced, and there is a disadvantage that it is difficult to supply abundant oil between the outer peripheral surface of the swash plate and the rotation prevention portion.

  The present invention has been made in view of such circumstances, and reduces wear caused by a file effect at the sliding contact portion between the outer peripheral surface of the swash plate and the rotation prevention portion of the piston, and is held on the outer periphery of the swash plate. The main object is to provide a swash plate type compressor that can increase the amount of oil that is produced and, in turn, can improve the durability and reliability of the swash plate in sliding contact.

  To achieve the above object, a swash plate compressor according to the present invention includes a housing, a piston fitted into a cylinder bore formed in the housing, a shaft rotatably supported by the housing, A swash plate housed in the housing and rotated in accordance with the rotation of the shaft, and slidably engages an outer edge portion of the inclined surface of the swash plate with a mooring recess formed in the piston via a pair of shoes. As the swash plate rotates, the piston is reciprocated in the cylinder bore, and a rotation preventing portion that can slide in contact with the outer peripheral surface of the swash plate is formed in the anchoring recess. In the configuration for preventing the swash plate, a plurality of grooves inclined in the same direction as the swash plate with respect to a surface orthogonal to the axis of the shaft are provided on the outer peripheral surface of the swash plate.

  Therefore, the grooves formed on the outer peripheral surface of the swash plate are formed in a direction inclined in the same direction as the swash plate with respect to the surface orthogonal to the shaft axis, so that the groove forming angle with respect to the slope of the swash plate is The angle of inclination of the swash plate with respect to the surface perpendicular to the axis of the shaft can be made smaller, and the file effect (wear) when the outer peripheral surface of the swash plate is in sliding contact with the rotation prevention portion of the piston is reduced. . Further, since the groove length in the circumferential direction can be made longer than that in the prior art, the amount of oil retained can be increased.

Here, it is preferable that at least one of the plurality of grooves is continuously formed on the entire outer periphery of the swash plate.
In such a configuration, at least one oil can be held over the entire circumference of the outer peripheral surface of the swash plate, so that it is possible to maintain good lubrication with the rotation preventing portion of the piston. Thus, it is possible to further improve the durability and reliability at the sliding contact portion of the swash plate.

  In particular, it is desirable that the plurality of grooves be formed in parallel with the slope of the swash plate (the shoe sliding surface of the swash plate). In such a configuration, there is no file effect at the sliding contact portion with the rotation prevention portion of the piston, and all the grooves are formed continuously over the entire circumference of the swash plate, so that the amount of oil retained is small. Get very good.

  The plurality of grooves may be formed with an angle difference of 10% or less with respect to an inclination angle of the swash plate with respect to a plane orthogonal to the axis of the shaft. Actually, it is not always easy to form a groove parallel to the slope of the swash plate, so that a groove formation error is expected and one or more continuous grooves are formed over the entire circumference of the outer peripheral surface of the swash plate. For this, it is desirable to form the groove at an inclination angle within the above-mentioned range.

  Further, in order to enhance the durability of the outer peripheral surface of the swash plate and maintain the oil retaining state, it is desirable to further apply a wear-resistant coating on the outer peripheral surface of the swash plate so that the groove shape remains. .

  As described above, according to the present invention, since the outer peripheral surface of the swash plate is provided with a plurality of grooves inclined in the same direction as the swash plate with respect to the surface orthogonal to the shaft axis, The groove formation angle with respect to the inclined surface can be made smaller than the inclination angle with respect to the plane perpendicular to the axis of the shaft of the swash plate, and the file effect at the sliding contact portion with the rotation prevention portion of the piston (wear) Since the groove length can be increased, the amount of oil retained on the outer peripheral surface of the swash plate can be increased, and the durability and reliability of the swash plate at the sliding contact point can be increased. Can be improved.

FIG. 1 is a cross-sectional view showing a configuration example of a swash plate compressor according to the present invention. FIG. 2A is an enlarged sectional view of the front cylinder block and the rear cylinder block of the swash plate compressor according to the present invention, and FIG. 2B is a mooring recess (bridge portion) of the piston. It is the enlarged view which looked at the swash plate which contacts this from the axial direction, and is sectional drawing cut | disconnected by the II line | wire of FIG. FIG. 3 is a side view showing an example of a swash plate. FIG. 4 is a side view showing another example of the swash plate. FIG. 5 is a view showing a state in which a coating is applied to the outer peripheral surface of the swash plate.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 shows a fixed capacity swash plate type piston compressor used in a refrigeration cycle using a refrigerant as a working fluid.

  The compressor is assembled via a valve plate 3 on the front side cylinder block 1, the rear side cylinder block 2 assembled to the front side cylinder block 1, and the front side (left side in the figure) of the front side cylinder block 1. And a rear head 6 assembled to the rear side (right side in the drawing) of the rear cylinder block 2 via a valve plate 5. The front head 4, the front side cylinder block 1, the rear side cylinder block 2, and the rear head 6 are fastened in the axial direction by fastening bolts 7, and constitute a housing of the entire compressor.

  Inside the front cylinder block 1 and the rear cylinder block 2, a crank chamber 8 defined by assembling the respective cylinder blocks is provided. The crank chamber 8 is rotatably supported by shaft support holes 9 and 10 formed in the front cylinder block 1 and the rear cylinder block 2 via bearings 11 and 12, and one end projects from the front head 4. A shaft 13 is provided. A seal member 14 for preventing refrigerant leakage is disposed between the tip of the shaft 13 and the front head 4, and an electromagnetic clutch (not shown) is attached to the tip of the shaft 13 protruding from the front head 4. It is like that.

  Each cylinder block 1, 2 is formed with a plurality of cylinder bores 15 arranged in parallel to the shaft support holes 9, 10 and at equal intervals on the circumference centered on the shaft 13. A double-headed piston 16 having heads 16a at both ends is inserted into each cylinder bore 15 so as to be reciprocally slidable. A compression chamber 17 is defined between the double-headed piston 16 and the valve plates 3 and 5. ing.

A swash plate 20 that is housed in the crank chamber 8 and rotates together with the shaft 13 is formed integrally with the shaft 13.
As shown in FIG. 2A, the swash plate 20 is rotatably supported via thrust bearings 21 and 22 with respect to the front cylinder block 1 and the rear cylinder block 2. It is moored in a mooring recess 16b formed in the center of the double-headed piston 16 via a pair of hemispherical shoes 23a, 23b slidably engaged so that the portion is sandwiched from the front and rear. Therefore, when the shaft 13 rotates and the swash plate 20 rotates, the rotational motion is converted into the reciprocating motion of the double-headed piston 16 via the shoes 23a, 23b, and the volume of the compression chamber 17 changes.

  Each of the valve plates 3 and 5 is opened and closed by suction holes 3a and 5a that are opened and closed by a suction valve (not shown) provided on the end face on the cylinder block side and a discharge valve (not shown) provided on the end face on the cylinder head side. Discharge holes 3b and 5b are formed corresponding to the respective cylinder bores 15. Further, the front head 4 and the rear head 6 have suction chambers 4a and 6a for storing the refrigerant supplied to the compression chamber 17 and discharge chambers 4b and 6b for storing the refrigerant discharged from the compression chamber 17, respectively. Is formed. In this example, the suction chambers 4a and 6a are formed at substantially the center of the respective heads 4 and 6, and the discharge chambers 4b and 6b are formed around the suction chambers 4a and 6a.

  Also, the housing sucks refrigerant from the external cycle and communicates with the suction chambers 4a and 6a (not shown) and the discharge chambers 4b and 6b, and discharges the compressed refrigerant to the external cycle (not shown). A discharge port is formed.

  In such a configuration, the anchoring recess 16b of the double-headed piston 16 is formed with a rotation preventing portion 16c capable of sliding contact with the outer peripheral surface 20a of the swash plate 20 in order to prevent the piston 16 from rotating. As shown in FIG. 2 (b), the rotation preventing portion 16c is formed on the inner side of the bridge portion 16d that constitutes the back portion of the mooring recess 16b formed so as to bridge between the pair of head portions 16a of the double-headed piston 16. Both end portions in the circumferential direction of the portion facing the outer peripheral surface 20a of the swash plate 20 (both edges on the surface facing the outer peripheral surface 20a of the swash plate 20 of the bridge portion 16d when viewed from the axial direction of the piston 16) Part) is provided with a projecting portion capable of coming into contact with the outer peripheral surface 20a of the swash plate 20, and the outer periphery 20a of the swash plate 20 is brought into contact with the rotation preventing portion 16c so that the rotation of the piston 16 occurs. Try to prevent.

Further, as shown in FIG. 3, a plurality of grooves 30 are formed in the circumferential direction on the outer peripheral surface 20a of the swash plate 20 that is in sliding contact with the rotation preventing portion 16c. The plurality of grooves 30 are inclined in the same direction as the swash plate 20 with respect to a plane β orthogonal to the axis α of the shaft 13. In the example shown in FIG. 3, the plurality of grooves 30 are parallel to the inclined surface 20 b of the swash plate 20. Is formed. Although FIG. 3 exaggerates and describes the grooves 30 for convenience of explanation, in practice, a large number of grooves 30 are formed over the entire width of the swash plate at a pitch of several tens of μm to several hundreds of μm. It is formed to a depth of several tens of μm to several hundreds of μm.
Therefore, in this example, since each groove 30 is formed in parallel with the inclined surface 20b of the swash plate 20, each groove 30 is continuously connected to the outer peripheral surface 20a of the swash plate 20 over the entire circumference thereof. Is formed.

  Oil is stored in the lower part of the crank chamber 8, and the lower part of the swash plate 20 is immersed in the stored oil.

  In the above configuration, when the compressor is driven and the swash plate 20 rotates as the shaft 13 rotates, the swash plate 20 swings at a predetermined swing angle, and the pinton 16 is connected to the cylinder bore 15 via the pair of shoes 23a. It will slide back and forth inside. Further, since the rotation preventing portion 16c provided in the mooring recess 16b reciprocates while the piston 16 is in sliding contact with the outer peripheral surface 20a of the swash plate 20, the piston 16 rotates without rotating with respect to the axis of the piston 16 (rotates. Reciprocating).

  At this time, the contact pressure between the rotation preventing portion 16c and the outer peripheral surface 20a of the swash plate 20 may increase, but the outer peripheral surface 20a of the swash plate 20 has a large number of grooves 30 parallel to the inclined surface 20b of the swash plate 20. Therefore, the oil stored in the lower portion of the crank chamber 8 can be held in the groove 30 and guided to the sliding contact portion with the rotation preventing portion 16c, and each groove 30 has a swash plate. Since the oil is continuously formed over the entire circumference of the groove 20, even if the oil retained in the groove 30 moves in the groove, the oil is not lost from the outer periphery of the swash plate 20 and is stored in the lower part of the crank chamber 8. It is possible to hold the oil thoroughly over the entire circumference of the swash plate 20.

  Further, since each groove 30 is formed in parallel to the inclined surface 20b of the swash plate 20, even when the outer peripheral surface 20a of the swash plate 20 is in sliding contact with the rotation preventing portion 16c, the file effect by the outer peripheral surface 20a of the swash plate 20 is achieved. As a result, the wear of the outer peripheral surface 20a of the swash plate 20 and the rotation preventing portion 16c can be greatly reduced.

In the above configuration, an example in which a large number of grooves 30 formed on the outer peripheral surface 20a of the swash plate 20 are formed in parallel to the inclined surface 20b of the swash plate 20 is shown. However, grooves formed on the outer peripheral surface 20a of the swash plate 20 are illustrated. As long as 30 is inclined in the same direction as the swash plate 20 with respect to the plane β orthogonal to the axis α of the shaft 13, for example, as shown in FIG. 4, the axis 30 is orthogonal to the axis α of the shaft 13. The groove may be formed with an inclination angle θ1 smaller than the inclination angle θ0 of the swash plate 20 with respect to the surface β to be formed.
Even in such a case, as shown in the figure, it is possible to form the groove at an inclination angle such that at least one groove 30 is continuously formed over the entire outer periphery 20a of the swash plate 20. Preferably, in order to realize such a configuration, the plurality of grooves 30 are inclined with an angle difference within 10% with respect to the inclination angle θ0 of the swash plate 20 with respect to the plane β orthogonal to the axis α of the shaft 13. It is preferably formed at an angle θ1 (so that an angle difference with the inclination angle θ0 of the swash plate 20 is within 10% of the inclination angle of the swash plate).

  With such a configuration, it is possible to form at least one groove for retaining oil over the entire circumference on the outer peripheral surface 20a of the swash plate 20, so that abundant oil supply to the rotation prevention portion 16c is achieved. In addition, an increase in the file effect due to the groove 30 on the outer peripheral surface 20a of the swash plate 20 can be avoided.

  Furthermore, on the premise of the above-described configuration, as shown in FIG. 5, a wear-resistant coating 31 may be applied so that the shape of the groove 30 remains on the outer peripheral surface 20 a of the swash plate 20. For example, the same molybdenum disulfide-based coating as the inclined surface 20b of the swash plate 20 may be applied, or a fluororesin (PTFE) -based coating may be applied. In addition, although wear-resistant coating by DLC or nickel plating may be applied, since these are high in level, it is desirable to crush the edge portion of the processing eye for forming the groove 30 or to perform finish processing.

  By such a coating process, it becomes possible to further reduce the wear of the outer peripheral surface 20a of the swash plate 20 while maintaining the oil holding state, and even when the contact with the rotation preventing portion 16c becomes strong, it can sufficiently cope. And durability can be further improved.

  In the above-described embodiment, the case where the invention is applied to a fixed capacity type compressor provided with a double-headed piston 16 has been described. A similar configuration can be adopted for the compressor.

DESCRIPTION OF SYMBOLS 1 Front side cylinder block 2 Rear side cylinder block 4 Front head 6 Rear head 13 Shaft 15 Cylinder bore 16 Piston 16c Rotation prevention part 20 Swash plate 20a Outer peripheral surface 20b Slope 23a, 23b Shoe 30 Groove 31 Covering

Claims (5)

A housing, a piston fitted into a cylinder bore formed in the housing, a shaft rotatably supported by the housing, and a swash plate housed in the housing and rotated as the shaft rotates. The swash plate has a slanted outer edge portion slidably engaged with a mooring recess formed in the piston via a pair of shoes so that the piston moves into the cylinder bore as the swash plate rotates. In the swash plate type compressor, the piston is prevented from rotating by reciprocating and forming a rotation preventing portion capable of sliding contact with the outer peripheral surface of the swash plate in the mooring recess.
A swash plate compressor, wherein a plurality of grooves inclined in the same direction as the swash plate with respect to a surface orthogonal to the axis of the shaft are provided on an outer peripheral surface of the swash plate. The swash plate compressor according to claim 1, wherein at least one of the plurality of grooves is continuously formed on the entire outer periphery of the swash plate. The swash plate compressor according to claim 1 or 2, wherein the plurality of grooves are formed in parallel with the slope of the swash plate. 3. The oblique line according to claim 1, wherein the plurality of grooves are formed with an angle difference of 10% or less with respect to an inclination angle of the swash plate with respect to a plane orthogonal to the axis of the shaft. Plate type compressor. The swash plate compressor according to any one of claims 1 to 4, wherein a wear-resistant coating is provided on an outer peripheral surface of the swash plate so that the shape of the groove remains.

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