JPH074876U - Reciprocating compressor - Google Patents

Abstract

(57) [Summary] [Purpose] To stabilize the rotary system equipped in the compressor with a simple axial thrust bearing structure. [Structure] In a rotary system including a drive shaft 8 and a swash plate element, a forward axial thrust is received by a thrust bearing 21 interposed between the thrust bearing 21 and the housing 2, and a backward axial thrust is received in the cylinder block 1. Seat plate 2 made of fluororesin interposed between
2, the seat plate 22 is provided with a tightening margin that causes pre-deformation due to an abutment with the rotating system, so that the elastic restoring force of the seat plate 22 stably supports the rotating system. To do.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a compressor suitable for air conditioning of a vehicle, and more particularly to a multi-cylinder reciprocating compressor having a single-head piston inside.

[0002]

[Prior art]

 Conventionally known as this type of compressor are a constant-capacity compressor having a fixed swash plate and a variable-capacity compressor having a swash plate and an oscillating plate capable of tilt displacement. In these compressors, axial support is extremely important in addition to radial support in order to stabilize the rotary system including the drive shaft and the swash plate element. For example, in the variable displacement compressor disclosed in Japanese Utility Model Laid-Open No. 3-112582, a thrust bearing is arranged between an end surface of a rotating body fixed to a drive shaft and an inner side surface of a casing, while a rear side of the drive shaft is provided. Thrust traces (thrust bearings), disc springs, spacers (holding screws), etc. are interposed between the ends and the valve plate.

[0003]

[Problems to be solved by the device]

 However, the above-mentioned rotary thrust bearing structure has a large number of parts and associated processing and assembly man-hours, and it is difficult to say that it is satisfactory from the viewpoint of productivity. The present invention is to solve the technical problem to be solved by stabilizing the rotary system with an extremely simple and inexpensive axial thrust bearing structure.

[0004]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention can form a cylinder block having a plurality of bores arranged side by side and a crank chamber inside to close the front end of the cylinder block, and can rotate the drive shaft in cooperation with the cylinder block. A reciprocating compressor having a housing supported on the drive shaft and a single-head piston that linearly moves in the bore in association with a swash plate element fixed to the drive shaft in the crank chamber. In the rotary system including the elements, the forward thrust is received by the thrust bearing interposed between the housing and the rear thrust, and the backward thrust is the fluororesin interposed between the cylinder block and the cylinder block. A new structure is adopted in which the seat plate is made of a metal and the seat plate is provided with a tightening margin that causes pre-deformation due to the abutment with the rotating system.

In a preferred embodiment of the present invention, the seat plate is arranged so as to abut against a rear end surface or a step surface of the drive shaft.

[0006]

[Action]

 In other words, between the rotary system and the cylinder block, the only seat plate with a plate thickness larger than the axial gap formed is given a pre-deformation corresponding to its interference due to the collision with the rotary system. It is assembled. Therefore, the elastic restoring force of the seat plate, which works against the thrust bearing, buffers the axial thrust acting on the rotary system to always stably support the rotary system, and is unique to the seat plate made of fluororesin. Ensures durability with excellent thermal and mechanical properties.

[0007]

【Example】

 An embodiment of the present invention will be specifically described below with reference to FIG. In the figure, a housing 2 is connected to the front end of a cylinder block 1 forming a part of the outer contour of the compressor, and a cylinder head 3 having a suction chamber 5 and a discharge chamber 6 is formed at the rear end of the cylinder block 3 with a valve plate 4. Are connected through. A drive shaft 8 connected to a power source is inserted into a crank chamber 7 formed in the housing 2, and the drive shaft 8 is rotatably supported by the cylinder block 1 and the housing 2. A rotation support 9 is fixed on the drive shaft 8 in the crank chamber 7, and a long hole 10a is formed at the tip of a support arm 10 extending to the rear surface side of the rotation support 9. A pin 11 is slidably fitted in the elongated hole 10a, and a rotary swash plate 12 is tiltably connected to the pin 11.

A sleeve 13 is loosely fitted on the drive shaft 8 adjacent to the rear end of the rotary support 9, and is constantly urged toward the rotary support 9 by a coil spring 14, and the left and right of the sleeve 13 are The pivots 13a (only one of which is provided) projecting from both ends are fitted into the engaging holes (not shown) of the rotary swash plate 12, and the rotary swash plate 12 is supported so as to be able to swing around the pivot 13a. .

A swing plate 15 is supported on the rear surface side of the rotary swash plate 12 so as to be rotatable relative thereto, and a guide portion 15 a provided at an outer edge portion is engaged with a through bolt 16 to restrain rotation thereof. A single-head piston 18 in a bore 17 penetrating the cylinder block 1 and the oscillating plate 15 are connected by a connecting rod 19. Therefore, the rotary motion of the drive shaft 8 is converted into the back-and-forth swing of the rocking plate 15 via the rotary swash plate 12, and the single-head piston 18 reciprocates in the bore 17 to move the suction chamber 5 to the bore 17 inside. The refrigerant gas sucked in is discharged to the discharge chamber 6 while being compressed. Then, the stroke of the single-head piston 18 and the tilt angle of the oscillating plate 15 change according to the pressure difference between the crank chamber pressure and the suction chamber pressure, and the discharge capacity is controlled. The crank chamber pressure is controlled by the opening / closing control valve 20 mounted in the cylinder head 3 based on the cooling load.

Next, the axial thrust support structure of the rotary system, which is the most characteristic feature of the present invention, will be described. The so-called rotary system including the drive shaft 8 and the swash plate element (the rotary support 9, the rotary swash plate 12 and the sleeve 13 of this embodiment) has a shaft thrust acting forward in the rotary support 9 and the housing 2. A shaft thrust force, which is received by a thrust bearing 21 interposed between the side surface and the rear side surface, is also interposed between the rear end surface of the drive shaft 8 and the cylinder block 1 and is made of a fluororesin seat plate 22. Configured to be accepted by.

That is, a countersunk portion 23 for landing the seat plate 22 is provided in the central shaft hole of the cylinder block 1, and is formed between the bottom surface of the countersunk portion 23 and the rear end surface of the drive shaft 8. The seat plate 22 having a plate thickness larger than the gap H is assembled by being given a pre-deformation corresponding to its tightening margin Δt in balance with the drive shaft 8. Therefore, the elastic restoring force of the seat plate 22 that opposes the thrust bearing 21 buffers the axial thrust acting on the rotating system including the drive shaft 8 to stably and stably support the rotating system. The seat plate 22 made of a fluororesin ensures excellent durability due to its excellent thermal and mechanical properties.

FIG. 2 shows another embodiment of the present invention. In this embodiment, a seat plate 22a is provided between the center front end surface 1a of the cylinder block 1 and a step surface 8a formed on the drive shaft 8. Although the seat plate 22a is interposed, the characteristics and functions of the seat plate 22a are not different from those of the previous embodiment, but selective application according to the form of the compressor is sufficiently possible. Most of the above cylinder blocks 1 are made of aluminum alloy, and although not shown in the drawings, a rotation stopper is appropriately provided between the seat blocks 22 and 22a that come into contact with the cylinder blocks 1 to prevent rotation sliding. It can also be configured to apply.

Although the swing plate type variable displacement compressor has been mainly described above, the present invention is not limited to the swing plate type, the rotary swash plate type or the constant displacement type, and the variable displacement type. Instead, the point is applicable to all reciprocating compressors with single-headed pistons.

[0014]

[Effect of device]

 As described above in detail, since the present invention has the configuration described in the scope of claims for utility model registration, it has a very simple and inexpensive axial thrust bearing structure that stabilizes the rotating system including the drive shaft. In addition to being able to support it, excellent durability is guaranteed especially by adopting a fluororesin seat plate. It should be noted that even if the seat plate is abraded, the resin material does not cause a substantial adverse effect such as metal powder, which is an effect that cannot be overlooked.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the whole of a reciprocating compressor according to an embodiment of the present invention.

FIG. 2 is a sectional view of a main part showing another embodiment of the present invention.

[Explanation of symbols]

1 is a cylinder block, 2 is a housing, 7 is a crank chamber, 8 is a drive shaft, 9 is a rotary support, 12 is a rotary swash plate, 1
8 is a single head piston, 21 is a thrust bearing, 22 and 22a
Is a seat

Claims (3)

[Scope of utility model registration request] 1. A cylinder block having a plurality of bores arranged side by side, and a housing for forming a crank chamber therein to close the front end of the cylinder block and rotatably supporting a drive shaft in cooperation with the cylinder block. A reciprocating compressor having a swash plate element fixed to the drive shaft in a crank chamber and linearly moving in the bore in a reciprocating compressor, the rotary system including the drive shaft and the swash plate element The forward axial thrust is received by the thrust bearing interposed between the housing and the rear axial thrust by the seat plate made of fluororesin interposed between the thrust bearing and the cylinder block. A reciprocating compressor that is received and is provided with a tightening margin that is pre-deformed by an abutment with the rotating system. 2. The compressor according to claim 1, wherein the seat plate abuts on a rear end surface of the drive shaft. 3. The compressor according to claim 1, wherein the seat plate is in contact with a step surface of the drive shaft.