JPH0540301Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a rotation prevention mechanism for a swinging inclined plate in a variable capacity compressor used for vehicle air conditioning.

[Prior art] The inclination angle of the oscillating inclined plate is changed according to the differential pressure between the crank chamber pressure and the suction pressure in the housing.
In a wobble-type variable capacity compressor that controls compression capacity, a mechanism for tilting the swinging inclined plate is configured as follows. That is, a rotary support is mounted on the drive shaft so as to be able to rotate synchronously, a rotary drive plate is attached to the rotary support so as to be tiltable in the front-rear direction, and the rotary drive plate has a swinging inclined plate that reciprocates the piston. are fitted in such a way that they can be tilted back and forth by a rotation prevention mechanism including a guide rail installed parallel to the drive shaft, but cannot rotate around the drive shaft.

As the above-mentioned rotation prevention mechanism, the applicant of the present application has proposed the one shown in Japanese Patent Application Laid-Open No. 61-291783.
As shown in FIGS. 10 to 12, this anti-rotation mechanism has a slider 23 slidably fitted to the guide rail 22 so as to be able to reciprocate in the front and back direction and to be able to rotate around the rail 22, The left and right sliding surfaces 23b of the slider 23 are connected to each other by engagement pins 24 so that the shoe 25 can be rotated and the slider 23 can be moved in the front and back directions in synchronization. 23 is formed into a convex arcuate sliding surface 25c, and the swinging inclined plate 1
The slide surface 25c is formed on the left and right inner surfaces of the fitting recess 19a formed on a part of the outer circumference of the inclined plate 19.
The arcuate slide grooves 19b are formed parallel to each other and guide in the radial direction.

[Problem to be solved by the invention] However, the rotation prevention mechanism of the swinging inclined plate of the variable capacity compressor mentioned above is machined with high precision to suppress rattling of each sliding member, so it is difficult to compress the compressor. In the case of liquid compression where the refrigerant is liquefied and stored indoors and is suddenly activated at high rotational speed, the following problems occur. That is, from the beginning to the end of the compression stroke, relative movement occurs in the vertical direction between the slider 23 and shoe 25 and the swinging inclined plate 19 as shown in FIG. 11, and the shoe 25 moves upward within the slide groove 19b. When the right side wall 19A of the swinging inclined plate 19 is receiving the compression reaction force, the left side wall 19B is in the suction stroke and is not receiving the compression reaction force, so that the swinging inclined plate 19 is in the twelfth position. In the figure, when the guide rail 22 is displaced in the same direction as the axial direction due to a strong external force in the direction of the arrow P due to the compression reaction force, the upper edge portion 25d of the arcuate slide surface 25c of the shoe 25 is moved into the arcuate slide groove 19b. Biting, arcuate slide groove 19b and shoe 25
There were problems in that not only the compressor was damaged, but also noise was generated, power was lost, and the swinging inclined plate 19 and shoe 25 were locked, making the compressor inoperable.

The present invention solves the above-mentioned problems of the prior art, and prevents abnormal contact or digging between the arcuate slide groove of the swinging inclined plate and the upper edge of the shoe even if the compressor load fluctuates rapidly. An object of the present invention is to provide a rotation prevention mechanism for a swinging inclined plate in a variable capacity compressor that can improve reliability.

[Means for Solving the Problems] In order to achieve the above object, the present invention makes it possible for the slider to reciprocate in the back and forth direction with respect to a guide rail arranged parallel to the drive shaft, and also to rotate around the guide rail. The shoe is fitted to the left and right sliding surfaces of the slider so as to be rotatable along the sliding surfaces using engagement pins, and the opposite side of the shoe from the slider is formed into a convex shape. A convex sliding surface of the shoe is formed on the outer periphery of the swinging inclined plate, and a convex sliding face of the shoe is formed on both left and right sides of a fitting recess for inserting the guide rail. Concave arcuate slide grooves that guide in a substantially radial direction are formed parallel to each other, so that the swinging inclined plate is guided so as to be non-rotatable around the drive shaft but tiltable in the front-rear direction. In a variable displacement compressor, a concave groove capable of keeping an edge portion of a convex slide surface formed on the shoe in a non-contact state at the end of a compression stroke with an inner end of the arcuate slide groove formed on the swinging inclined plate. We are taking steps to form a

[Function] In the present invention, a concave groove is formed in the arcuate slide groove of the swinging inclined plate to prevent the inner end of the shoe from coming into contact with the arcuate slide groove at the end of the compression stroke. The shoe does not dig into the arcuate slide groove, and the shoe reciprocates smoothly within the arcuate slide groove, suppressing noise generation and damage to the swinging inclined plate or the shoe.

[Example] Below, an example embodying the present invention is shown in Figs.
This will be explained according to FIG.

As shown in FIG. 2, a front housing 3 forming a crank chamber 2 is bonded and fixed to the left end surface of the cylinder block 1. Further, a rear housing 5 is fixedly connected to the right end surface of the cylinder block 1 via a valve plate 4. Further, a plurality of cylinder chambers 1a (only one is shown) are provided through the cylinder block 1 in parallel with each other and spaced apart at equal angles.
Pistons 6 are accommodated in the cylinder chambers 6 so as to be able to reciprocate back and forth by a drive mechanism to be described later, and refrigerant gas is supplied to the cylinder chamber 1a from a suction chamber 7 formed in the rear housing 5 through an inlet 8 provided in the valve plate 4. Refrigerant gas is sucked into the refrigerant gas and compressed by the piston 6, and is discharged from a discharge port 9 provided in the valve plate 4 to a discharge chamber 10 provided in the rear housing 5.

A drive shaft 11 is connected to the center of the cylinder block 1 and front housing 3 via a bearing.
is supported on the drive shaft 11, and the crank chamber 2 is supported on the drive shaft 11.
A rotary support body 12 is fitted and fixed so as to be able to rotate synchronously so as to be located inside. Moreover, the rotation support body 1
2 has a connecting pin 13 engaged with the elongated hole 12a.
The rotary drive plate 14 is mounted so as to be tiltable in the front-rear direction (horizontal direction in FIG. 2) and rotatable integrally with the rotary support 12.

As shown in FIGS. 2 and 3, a sleeve 15 is fitted onto the drive shaft 11 so as to be able to reciprocate in the axial direction, and a pair of pins 16 are fixed to the sleeve 15. The rotary drive plate 14 is engaged with an engagement hole 14b formed in the boss portion 14a of the rotary drive plate 14, and can tilt and guide the rotary drive plate 14 in the front-rear direction along the drive shaft 11.

A swinging inclined plate 19 is supported on the rotary drive plate 14 via a journal bearing 17 and a thrust bearing 18 so as to be tiltable in the front and back direction together with the drive plate 14, and non-rotatably supported by a rotation prevention mechanism 21 which will be described in detail later. has been done. The left end portions of the piston rods 20 connected to the respective pistons 6 are connected to the swinging inclined plate 19, and the rotation of the drive shaft 11 rotates the rotary support 12.
When the piston 9 is tilted back and forth, the piston 6 is reciprocated via the piston rod 20. Then, the piston stroke changes according to the differential pressure between the crank chamber pressure in the crank chamber 2 and the suction pressure in the suction chamber 7, and the inclination angle of the rocking inclined plate 19 changes, so that the compression capacity is controlled. It's summery.

Next, the rotation prevention mechanism 21 of the swinging inclined plate 19 according to the present invention, which allows the swinging inclined plate 19 to tilt in the front-rear direction and prevents its rotation, will be described in detail.

A guide rail 22 passes through the cylinder block 1 and the front housing 3 in parallel with the drive shaft 11 and through a fitting recess 19a formed in the lower end of the swinging inclined plate 19.
The cylindrical portion 22a of the guide rail 22 has an insertion hole 23 through which a cylindrical slider 23 penetrates in the diametrical direction so as to be perpendicular to the axial direction of the rail 22.
a allows sliding in the front and back direction, and the cylindrical part 2
It is fitted so as to be rotatable around 2a. Engagement pins 24 are integrally provided on sliding contact surfaces 23b at both left and right ends of the slider 23 in a flat shape, and an engagement pin 24 is provided through the center of a shoe 25 having a substantially semi-cylindrical shape. The slider 23 is engaged with the mating hole 25a, and the planar sliding contact surface 25b of the shoe 25 is engaged with the slider 23.
The shoe 25 is rotatable about the pin 24 while in sliding contact with the sliding surface 23b. This show 2
A convex arcuate slide surface 25c is formed on the opposite side of the slider 23 of No. 5.

On the other hand, concave arcuate slide grooves 19b are formed on both left and right inner surfaces of the fitting recess 19a of the swinging inclined plate 19 so as to extend in the radial direction of the inclined plate 19. In this arcuate slide groove 19b, an arcuate slide surface 25 of the shoe 25 is provided.
c is slidably fitted so as to be relatively movable in the radial direction and relatively rotatable along the arcuate slide groove 19b.

When the shoe 25 is moved upward at the end of the compression stroke, as shown in FIG. A concave groove 19c, which is an important part of the present invention, is formed to prevent contact with the groove 19b.
The formation width of this concave groove 19c is the same as that of the arcuate slide groove 1.
Approximately one-third of the total length of 9b is desirable.

The guide rail 22 and shoe 25 are made of iron-based material, and the slider 23 is made of high-Si-based Al material (for example, A390).

In this embodiment, the rotation prevention mechanism 21 is located at the lowest part of the crank chamber 2, and the oil stored in the crank chamber is supplied to the slider 23, shoe 25, and the like.

Next, the operation of the variable displacement compressor constructed as described above will be explained.

Now, when the drive shaft 11 is rotated by the power of an engine or the like, the swinging inclined plate 19 is tilted back and forth in a rotationally restricted state by the rotation prevention mechanism 21 via the rotating support 12, the connecting pin 13, and the rotating drive plate 14. be done.
As a result, each piston 6 is reciprocated via the piston rod 20, and the refrigerant gas sucked from the suction chamber 7 through the suction port 8 into the compression chamber of the cylinder chamber 1a is compressed in the compression chamber, and then the refrigerant gas is compressed in the compression chamber. The liquid is pumped into the discharge chamber 10 through the .

In FIG. 2, when the swinging inclined plate 19 is tilted in the front-back direction about the connecting pin 13, the slide groove 19b formed in the inclined plate 19 is displaced in the front-back and up-down directions while changing the angle of inclination. This displacement of the inclination angle of the slide groove 19b is allowed because the shoe 25 can rotate around the pin 24 with respect to the slider 23, and the displacement in the front-rear direction is allowed so that the slider 23 can slide in the front-rear direction with respect to the guide rail 22. Therefore, the displacement in the vertical direction is allowed due to the circular arc slide groove 19b of the swinging inclined plate 19.
On the other hand, this is allowed because the convex arc sliding surface 25c of the shoe 25 is slidable in the vertical direction.

Further, the swinging inclined plate 19 receives an external force (see arrow) in the direction of pressing the shoe 25 in FIG. In addition, since the slide groove 19b of the inclined plate 19 can move relative to the convex arcuate slide surface 25c of the shoe 25, the slide groove 19b does not come into partial contact with the convex slide surface 25c. Local wear of the sliding parts is prevented.

Furthermore, at the end of the compression stroke when the slider 23 and shoe 25 are located near the top dead center as shown in FIG. When receiving a large compression reaction force (see arrow P) as shown in
The swinging inclined plate 19 receives a torsional force in the same direction, but because of the concave groove 19c, the edge portion 25d of the shoe 25 does not come into contact with the surface of the slide groove 19b, and as a result, the edge portion 25d does not slide. Biting into the groove 19b is prevented, and noise and damage to each sliding member are suppressed.

Note that the present invention can also be embodied as follows.

(1) As shown in Fig. 7, an oil passage 23c is inserted into the insertion hole 23 for the slider 23 to improve lubricity.
A is installed through the shaft so as to communicate with the shaft 2.
5, an oil groove 25e is formed in a cross shape on the sliding contact surface 25b.
may be engraved.

(2) As shown in FIG. 8, a spiral oil groove 23d is provided in the insertion hole 23a of the slider 23, and the
An annular oil groove 25e may also be formed on the sliding surface 25c of No. 5.

(3) As shown in FIG.
The engagement hole 25a may also be formed in the same shape.

[Effects of the invention] As detailed above, this invention prevents abnormal contact between the sliding groove of the oscillating inclined plate and the edge of the shoe when the load changes suddenly, such as when the compressor compresses liquid refrigerant. This has the effect of preventing premature wear of the swinging inclined plate and shoe or damage of the sliding members, reducing noise, and improving durability and reliability.

[Brief explanation of the drawing]

1 to 6 show an embodiment of the rotation prevention mechanism of the swinging inclined plate in the variable displacement compressor of the present invention, FIG. 1 is an exploded perspective view of only the rotation prevention mechanism, and FIG. 2 is an exploded perspective view of only the rotation prevention mechanism. Fig. 3 is an enlarged sectional view taken along the line A-A in Fig. 2;
5 and 5 are respectively enlarged sectional views of the vicinity of the anti-rotation mechanism, FIG. 6 is a sectional view taken along line B-B in FIG.
9 to 9 are exploded perspective views showing other examples of the rotation prevention mechanism of the present invention, FIGS. 10 to 12 show conventional rotation prevention mechanisms, and FIG. 10 is an exploded perspective view,
FIG. 11 is a sectional view showing the assembled state, and FIG. 12 is a sectional view taken along the line C--C in FIG. 11. Crank chamber...2, Suction chamber...7, Discharge chamber...
10, Drive shaft...11, Rotating support body...12, Rotating drive plate...14, Swinging inclined plate...19, Fitting recess...19a, Arc slide groove...19b, Concave groove...19c , rotation prevention mechanism...21, guide rail...22, slider...23, insertion hole...2
3a, sliding surface...23b, engaging pin...24, shoe...25, engaging hole...25a, sliding surface...2
5b, arc sliding surface...25c, edge part...
25d.

Claims (1)

[Claims for Utility Model Registration] A rotary support is attached to the drive shaft so that it can rotate synchronously, a rotary drive plate is attached to the rotary support so that it can be tilted back and forth, and a piston is mounted on the rotary drive plate to reciprocate. A swinging inclined plate is fitted so that it can be tilted back and forth, while a slider can be moved back and forth in the back and forth direction relative to a guide rail that is arranged parallel to the drive shaft.
and is rotatably fitted around the guide rail,
A shoe is fitted to the flat left and right sliding surfaces of the slider so as to be rotatable along both sliding surfaces using engagement pins, and the opposite side of the shoe to the slider is fitted with a convex surface. A convex sliding surface of the shoe is formed on the outer periphery of the swinging inclined plate, and a convex sliding face of the shoe is formed on both left and right sides of a fitting recess for inserting the guide rail. Concave arcuate slide grooves that guide in a substantially radial direction are formed parallel to each other, so that the swinging inclined plate is guided so as to be non-rotatable around the drive shaft but tiltable in the front-rear direction. In a variable displacement compressor, a concave groove capable of keeping an edge portion of a convex slide surface formed on the shoe in a non-contact state at the end of a compression stroke with an inner end of the arcuate slide groove formed on the swinging inclined plate. A rotation prevention mechanism for a swinging inclined plate in a variable displacement compressor.