JPS631774A - Self-exciting vibration preventing mechanism for suction valve of rocking cam plate type compressor - Google Patents

Abstract

PURPOSE:To prevent production of self-exciting vibration of a suction valve and the generation of noise due to the self-exciting vibration, by a method wherein a lift allowable amount of the suction valve is automatically regulated in linkage with a change in the rocking inclination angle of a wobble plate. CONSTITUTION:A stopper material 23 is forward and backward movably engaged in a manner to be positioned facing the tip part of a suction valve 11 with a spring 29 therebetween, and is moved forward and backward through the change in the rocking inclination angle of a dry plate 20 and the wobble plate 21. Namely, under a state in that a cooling load in a car room is high and a piston 16 is reciprocated with a high stroke left, a high life allowable amount is obtained. Under a state in that a cooling load in a car room is low and the piston 16 is reciprocated with a low stroke left, a low lift allowable amount is obtained. This constitution enables prevention of production of self- exciting vibration of the suction valve 11 and the generation of noise due to the self-exciting vibration.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is capable of changing the compression capacity by changing the swinging inclination angle of the wobble plate in response to changes in the cooling load in the vehicle interior. A rocking swash plate type compressor installed in a compressor, more specifically, when the cooling load is large, by increasing the inclination angle of the wobble plate, the piston moves back and forth with a large stroke in each cylinder bore. A oscillating swash plate type compression system is provided so that the piston moves forward and backward with a small stroke by gradually reducing the inclination angle of the wobble plate as the cooling load decreases. The present invention relates to an improvement for preventing self-excited vibrations occurring in a suction valve provided in opposition to a suction port opening into each cylinder bore in a machine.

[Conventional technology]

Generally, in a rocking swash plate type compressor, as shown in FIGS. 7 and 8, a plurality of cylinder bores 14 are provided in parallel at regular intervals along the circumferential direction, and each cylinder A compression chamber 15 is provided in the bore 14 between the valve plate 4 and the valve plate 4.
The piston 16 is inserted into the crank chamber 13 so as to be able to move forward and backward, while a wobble plate 21 is swingably provided in the crank chamber 13 and connected to the piston 16. 16 is provided so as to obtain a compression effect by moving it forward and backward continuously. The wobble plate 21 is provided so that its tilt angle can be changed in response to changes in the cooling load in the vehicle interior, and when the cooling load in the vehicle interior is large, the wobble plate 21 swings. By increasing the inclination angle, a large piston stroke (large compression capacity) can be obtained, and in a state where the cooling load in the vehicle interior is small, the piston stroke can be reduced by reducing the swing inclination angle of the wobble plate 21 ( It is provided so that the compression capacity can be reduced. Furthermore, each cylinder bore 14 is provided with a notch step (stopper) 22 corresponding to the tip of the suction valve 11.
A stopper 22 is provided to restrict the opening amount (lift amount) of the suction valve 11.

[Problem that the invention seeks to solve]

However, as mentioned above, a fixed stopper (stepped notch) is provided on the inner wall surface of the cylinder bore facing the suction valve, and the opening amount (lift amount) of the suction valve is ) In the case of a conventionally structured oscillating swash plate type compressor that is installed to regulate the When the suction amount decreases due to the shortening of the piston stroke in each cylinder bore, the opening amount (lift amount) of the suction valve decreases and a state is achieved in which the suction valve contacts the stopper (stepped notch). Since the suction valve is not in contact with the stopper (stepped notch), self-excited vibration occurs in the suction valve, and noise is generated due to the self-excited vibration. There is a problem in that it causes the following inconvenience.

The present invention attempts to improve the problem in order to solve the above-mentioned problems.The present invention is an attempt to improve the above-mentioned problems. In other words, when the cooling load is large (i.e., the piston advances and retreats with a large stroke), the intake valve has a large opening amount (lift amount). If a large lift capacity is obtained corresponding to the opening of the
In other words, the problem should be solved by making it possible to reduce the allowable lift amount in response to the smaller opening amount (lift amount) of the intake valve in the state where the piston advances and retreats with a small stroke. There are problems. That is, the present invention is characterized in that the above-mentioned problem is solved by making it possible to automatically adjust the lift tolerance of the intake valve in conjunction with changes in the swinging inclination angle of the wobble plate. The specific means and effects are as follows.

[Means for solving problems]

A plurality of cylinder bores are bored in the cylinder block in parallel with the drive shaft so as to surround the drive shaft, and a piston is fitted into each cylinder bore so as to be able to move forward and backward, while communicating with the cylinder bore to form a crank chamber. On the same day, the drive plate was installed in the tank chamber so that the inclination angle of the drive plate could be changed through a lug plate that was axially mounted on the drive shaft and a sleeve that was loosely fitted to the drive shaft so that it could slide freely in the front and rear directions. In a wobble plate type compressor, a wobble plate is provided to be freely rotatable, and a wobble plate whose rotation is restricted is attached to the drive plate so as to be swingable, and the wobble plate and each of the pistons are connected by connecting rods, A stepped notch is provided on the inner wall surface of the cylinder bore so as to face the tip of the suction valve.

■ A race is provided in the crank chamber so that it can slide freely by loosely fitting it onto the drive shaft.The race is provided in such a way that one end of the race can be brought into contact with the sleeve, and a stopper rod is provided extending from the race, and the end of the race is provided so that it can be brought into contact with the sleeve. The part is made to freely appear and retract from the step of the notch.

■ A spring is interposed between the race and the cylinder block so that the race and stopper rod are normally biased in the direction of contact with the sleeve.

[For production]

■ Conditions where the cooling load is large The drive plate and wobble plate are in a state of swinging with a large angle of inclination, and the piston moves back and forth with a large stroke in each cylinder bore. During the suction stroke, a large negative pressure is generated in each compression chamber, which allows the suction valve to open with a large lift amount. In addition, since the drive plate and the wobble plate are in a state of swinging at a large angle of inclination as described above, the stopper rod is retracted toward the crank chamber through the biasing pressure of the spring, that is, the above-mentioned suction The effect of increasing the lift permissible amount corresponding to the lift amount of the valve can be obtained.

■ Condition where the cooling load is small The drive plate and wobble plate are in a state of swinging with a small angle of inclination, and the piston moves back and forth with a small stroke in each cylinder bore. During the suction stroke, the negative pressure generated in each compression chamber decreases, thereby achieving a state in which the amount of lift of the suction valve is reduced. In addition, since the drive plate and wobble plate are in a state of swinging with a small angle of inclination as described above, the sleeve pushes the stopper rod toward the notch step side, that is, the lift amount of the suction valve is reduced. The effect of reducing the allowable lift amount correspondingly can be obtained.

〔Example〕

Specific embodiments of the present invention will be described below with reference to illustrative drawings.

1 to 4 are drawings showing the first embodiment, and in each drawing, 1 indicates a cylinder block, 2 indicates a front housing, and 3 indicates a rear housing. The cylinder block 1 extends in the front-rear direction. One end is formed into a cylindrical shape, and a front housing 2 is mounted on one end of the front side.

A rear housing 3 is mounted on one end of the rear side with a valve plate 4 interposed therebetween. In the center of the front housing 2 is a drive shaft 1, which will be described later.
The bearing 7 is provided with the portion 5A, while the rear housing 3
A suction chamber 6 and a discharge chamber 7 are provided concentrically with an annular partition wall 8 interposed therebetween. That is, the suction chamber 6 is located at the center, and the discharge chamber 7 is located near the outer periphery so as to surround the suction chamber 6.

Further, the cylinder block 1 is provided with a bearing portion 5B at its center facing the bearing portion 5A, and a plurality of cylinder bores 14 extend in the front-rear direction around the bearing portion 5B at its outer periphery. The holes are drilled at regular intervals. Each cylinder bore 14 has a compression chamber 15 between it and the valve plate 4, into which a piston 16 is fitted so as to be able to move forward and backward. It is provided so as to selectively communicate with the suction chamber 6 and the discharge chamber 7 via the suction chamber 6 and the discharge chamber 7. That is, the suction port 9 is provided with a suction valve 11, and the discharge port 10 is provided with a discharge valve 12, respectively. Similarly, they are provided so as to open and close, respectively, through the compression stroke of the piston 16.

Furthermore, each cylinder bore 14 is provided with a notch step 22 on the inner wall surface of the cylinder bore 14 at a portion facing the tip of the suction valve 11, and the notch step 22 has a stopper as described later. The tip of the rod 23 is provided so that it can be moved in and out in conjunction with the swinging of the wobble plate 21.

- On the other hand, a crank chamber 13 is provided in the front housing 2 in communication with each of the cylinder bores 14, and the aforementioned drive shaft 17 is horizontally suspended in the crank chamber 13 between the two bearing portions 5A and 5B. be done. A lug plate 1 is attached to one end of the front side of the drive shaft 17.
8 is mounted on a shaft so that it can rotate together with the drive shaft 17. Therefore, the lug plate 18 is provided with a contact surface 18a for a sleeve 19, which will be described later, at its center, while
The support arm 18 of the drive plate 20 is attached to the peripheral edge of the drive plate 20.
A drive plate 20 formed in an annular shape so as to surround the drive shaft 17 is supported on the support arm 18b so as to be swingable along the longitudinal direction (back and forth direction) of the drive shaft 17. Further, the aforementioned sleeve 19 is connected to the drive plate 20 and is loosely fitted onto the drive shaft 17 so as to be freely slidable. That is, the sleeve 19 is connected to the drive plate 20 via a pair of left and right connecting pins 24, 24, and the drive plate 2
It is provided so that it can slide in the front and back direction in conjunction with the rocking of the o. The above-mentioned wobble plate 21 is connected to the drive plate 2o via a thrust bearing 25.
is swingably supported with its rotation restricted. Similarly to the drive plate 20, the wobble plate 21 is formed in an annular shape so as to surround the drive shaft 17, and the wobble plate 21 and each of the pistons 1
6 are connected by a connecting rod 26. More specifically, each wobble plate 21 and the piston 16 are connected so that each piston 16 is at the top dead center position when the support arm 18b is rotated to a position facing each cylinder bore 14. A race 27 is slidably fitted to the drive shaft 17 between the sleeve 19 and the cylinder block 1, while the cylinder block 1 has a crank chamber 13 and the notch stepped portion 22. A through hole 28 is bored through the gap, and the stopper rod 23 is fitted into the through hole 28 with one end connected to the race 27 so that it can move forward and backward. A spring 29 is interposed between the race 27 and the cylinder block 1, and the race 27 and the stopper rod 23 are normally biased toward the front side (sleeve 19 side) via the spring 29. It is set up as follows.

In other drawings, numeral 30 indicates a control valve.

Both FIG. 5 and FIG. 6 are drawings showing a second embodiment, in which a drive shaft 17 has two races 27 interposed between a sleeve 19 and a cylinder block 1.
A and 27B are slidably fitted into each other. The other race 27A is provided so as to be able to come into contact with the sleeve 19, and the stopper rod 23 is extended from the other race 27B. And also, both sides 2
A spring 29A is interposed between 7A and 27B, and a spring 29B is interposed between race 27B and cylinder block 1, respectively, and both springs 29A and 29B are provided with different spring pressures. That is, the spring 29A is provided with a weaker spring pressure than the spring 29B. Note that the number of laces 27 is not limited to two, but can be increased to three or more as appropriate. Further, in both of the embodiments described above, the tip of the stopper rod 23 is provided so as to be sunk into the through hole 28 from the notch step 22 when the cooling load is low.

It is also possible to provide the stopper rod 23 so that its tip end always projects into the notch step 22 by making the notch step 22 larger.

Next, its effect will be explained.

In the first embodiment shown in FIGS. 1 to 4, the first
The figure shows a state where the cooling load in the vehicle interior is large, and the drive plate 20 has a large angle of inclination in the crank chamber 13 and is in a state of rocking rotation together with the drive shaft 17.

Further, the wobble plate 21 is in a state of swinging at the same inclination angle as the drive plate 20 through the swing rotation of the drive plate 20. By obtaining a state in which the wobble plate 21 swings with a large inclination angle in this way, a state in which the piston 16 advances and retreats with a large stroke in each cylinder bore 14, (
(large capacity operation state) can be obtained. Furthermore, as the piston 16 moves back and forth with a large stroke, a large pressure difference (negative pressure) is generated between the suction chamber 6 and each compression chamber 15. The pressure allows the suction valve 11 to open with a large lift amount during the suction stroke of the piston 16. - On the other hand, when the drive plate 20 swings and rotates at a large angle of inclination as described above, the sleeve 19 that supports the drive plate 20 on the drive shaft 17 is in a state of sliding toward the front side. As a result, the race 27 and the stopper rod 23 are in a state of sliding toward the front side like the sleeve 19 through the biasing pressure of the spring 29.

That is, the tip of the stopper rod 23 is sunk into the through hole 28, and as a result, the notch step 22 provides a lift tolerance S corresponding to the lift of the suction valve 11. (In this embodiment, the maximum allowable lift amount of the suction valve 11 is set by the notch stepped portion 22).

By achieving such a large-capacity operating state for a certain period of time, the interior of the vehicle is cooled and its cooling load (evaporator heat load) is reduced. As the cooling load decreases, the drive plate 20 and wobble plate 21 in the crank chamber 13 swing at a small angle of inclination.
In this case, a state in which the piston 16 moves forward and backward with a small stroke, that is, a state shown in FIG. 2 (small capacity operating state) is obtained. In this way, the piston 16 moves forward and backward with a small stroke.

The pressure difference (negative pressure) generated between the suction chamber 6 and each compression chamber 15 will gradually decrease, and as the negative pressure in each compression chamber 15 decreases, the pressure difference of the piston 16 will decrease gradually. A state is obtained in which the lift amount of the suction valve 11 is reduced during the suction stroke.

- On the other hand, when the drive plate 20 swings and rotates with a small angle of inclination as described above, the sleeve 19 supporting the drive plate 2o slides toward the rear, causing the race 27 and the stopper rod to 23 overcomes the biasing pressure of the spring 29 and slides toward the rear.As the stopper rod 23 slides toward the rear in this way, the tip of the stopper rod 23 protrudes into the notched stepped portion 22, resulting in an effect of reducing the allowable lift amount of the suction valve 11. In other words, it is possible to obtain the allowable lift amount S' corresponding to the lift amount of the suction valve 11.

Further, in the second embodiment shown in both FIGS. 4 and 5, two races 27A and 27B are slidably provided in the crank chamber 13 by loosely fitting the drive shaft 17, and both races 27A , 27B and the same race 27
Two types of springs 29A and 29B with different spring pressures are interposed between B and the cylinder block 1, so that the swing inclination angle of the drive plate 20 (sleeve 19
The amount of forward and backward movement of the stopper rod 23 can be arbitrarily adjusted with respect to the amount of sliding movement of the stopper rod 23. That is, both bases 27
By setting the spring 29A interposed between A and 27B to a weaker spring pressure than the spring 29B interposed between the race 27B and the cylinder block 1, the swinging inclination angle of the drive plate 2o (the amount of sliding movement of the sleeve 19) ) The amount of forward and backward movement of the stopper rod 23 with respect to ) can be reduced.

〔Effect of the invention〕

The present invention is constructed as described above, and as described above, a stopper rod is inserted into the suction valve so as to be able to move forward and backward while facing the tip, and the stopper rod is used to swing the drive plate and the wobble plate. By moving the piston forward and backward by changing the angle of inclination, a large lift capacity can be obtained when the cooling load inside the vehicle is large and the piston moves forward and backward with a large stroke. By making it possible to obtain a small lift capacity when the cooling load is small and the piston advances and retreats with a small stroke, the same amount of lift can be obtained in response to changes in the lift amount of the intake valve due to changes in the piston stroke. It has now become possible to automatically change the allowable lift amount of the intake valve. In this way, by making it possible to change the allowable lift amount of the suction valve in response to changes in the lift amount of the suction valve, self-excited vibration of the suction valve and noise caused by the self-excited vibration can be reduced. It has now become possible to effectively prevent the occurrence of

Furthermore, in the present invention, a spring is interposed as a means for returning the stopper rod to the front side, thereby improving return characteristics when returning the drive plate and wobble plate from a small capacity operating state to a large capacity operating state. I was able to do it.

Also, as mentioned above, by making it possible to increase the lift capacity of the intake valve during large capacity operation,
The suction resistance to the compression chamber can be reduced, and by reducing the suction resistance in this way, the discharge temperature can be lowered accordingly. In other words, it has become possible to improve the reliability of the compressor.

Furthermore, as shown in the second embodiment, by interposing two or more types of springs with different spring pressures, it has become possible to arbitrarily set the optimum lift allowable amount. Ta.

[Brief explanation of drawings]

1 to 4 are drawings showing a first embodiment, and FIG. 1 shows the entire wobble plate compressor according to the present invention (the wobble plate swings at a large angle of inclination). Figure 2 is a cross-sectional view showing the entire swinging swash plate type compressor (state in which the wobble plate swings at a small angle of inclination).
3 is an enlarged sectional view of the suction valve and a stopper rod portion that regulates the lift amount of the suction valve. FIG. 4 is a sectional view taken along the line A--A in FIG. 3. Figures 5 and 6 are drawings showing the second embodiment, in which Figure 5 is a sectional view of the suction valve and the stopper rod portion that regulates the lift amount of the suction valve, and Figure 6 is the same operating state. FIG. Further, FIGS. 7 and 8 are drawings showing the conventional structure, and FIG. 7 is a cross-sectional view showing the entire swinging swash plate type compressor, and FIG. 8 is an enlarged cross-sectional view of the suction valve portion. DESCRIPTION OF SYMBOLS 1...Cylinder block, 2...Front housing, 3...Rear housing, 4...Valve plate, 5A, 5B...Bearing part, 6...Suction chamber, 7...Discharge Chamber, 8... Partition wall, 9...
Suction port, 10...Discharge port, 11...Suction valve, 12.
...Discharge valve, 13...Crank chamber, 14...Cylinder bore. 15... Compression chamber, 16... Piston, 17... Drive shaft, 18... Lug plate, 18a...
- Contact surface, 18b... Support arm, 19... Sleeve. 20... Drive plate, 21... Wobble plate, 22... Notch step, 23... Stopper rod, 24... Connection pin, 25... Thrust bearing. 26...Fun rod, 27.27A, 27B...lace, 28...through hole, 29,29A, 29B...
Spring, 30...control valve. Figure 5 Figure 6

Claims (2)

[Claims] (1) A plurality of cylinder bores are bored in the cylinder block in parallel with the drive shaft, and a piston is fitted into each cylinder bore so that it can move forward and backward, while a crank chamber is provided in communication with the cylinder bore. The chamber is provided with a lug plate that is axially mounted on the drive shaft, and a sleeve that is loosely fitted to the drive shaft so as to be slidable in the front and rear directions, so that the drive plate can be oscillated and rotated so that its inclination angle can be changed. In a wobble plate compressor, a wobble plate whose rotation is restricted is attached to the drive plate so as to be swingable, and the wobble plate and each of the pistons are connected by connecting rods, and a race is slid onto the drive shaft. A stopper rod is provided so that it can be freely fitted loosely and one end is brought into contact with the sleeve, and a stopper rod is extended from the same race, and its tip is made to face the tip of the suction valve on the inner wall surface of the cylinder bore. A spring is interposed between the race and the cylinder block so that the race and stopper rod are always biased in the direction of contact with the sleeve. A self-excited vibration prevention mechanism for a suction valve in a rocking swash plate compressor. (2) A patent in which a plurality of races are slidably fitted loosely onto a drive shaft, and springs are interposed between each race and between each race and the cylinder block, and each spring is provided with a different spring pressure. A self-excited vibration prevention mechanism for a suction valve in a rocking swash plate compressor according to claim 1.