JP2958574B2 - Rotation balance adjustment device for wobble plate compressor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wobble plate type variable displacement compressor used for a cooling cycle or the like, and more particularly to a device for adjusting the center of gravity of a rotating element.

(Prior art) A conventional wobble plate type variable displacement compressor is:
As shown in FIG. 5, a rotating member 9 for power transmission that rotates together with the drive shaft 7 is connected to the crank chamber 4 inside the compressor, and the rotating member 9 is connected to the rotating member 9 through a link mechanism.
The swing angle can be changed via a hinge ball 10 externally fitted to the drive shaft 7 and a wobble plate supporting rotating member 11 which rotates with the rotation of the power transmitting rotating member 9.
A wobble plate 19 interlocking with the piston 23 is attached to the rotating member 11 via a bearing so as to allow only swinging.

When the swing angle of the wobble plate 19, that is, the swing angle of the rotating member 11 for supporting the wobble plate is large, the stroke amount of the piston 23 is large.
When the swing angle is small, the stroke amount is small, and the swing angle of the rotating member 11 is changed by adjusting the pressure in the crank chamber by the pressure control valve 32.

(Problems to be Solved by the Invention) However, in general, in this type of compressor, in order to keep the center of gravity of the entire rotating members 9 and 11 on the axis of the drive shaft 7, for example, The balancer 9a is provided on the side opposite to the link mechanism with respect to the drive shaft 7, but even if such a fixed balancer 9a is provided, the stroke of the piston 23 changes, that is, the rotating member 11 for supporting the wobble plate. It is difficult to always maintain the center of gravity on the axis of the drive shaft 7 with respect to the change of the swing angle.

According to the result of actually measuring the balance state of the rotating member with respect to the stroke amount (the maximum stroke amount is assumed to be 100%), as shown in FIG. The moment on the side (B) on the side opposite to the link mechanism with respect to the shaft 7 increases substantially linearly with an increase in the stroke amount, but the change is not the same. FIG. 4 (b)
As shown in the figure, as the stroke amount increases, the center of gravity of the entire rotating members 9 and 11 shifts from the side with the link mechanism to the opposite side, and it is impossible to balance the rotation in the entire stroke range. there were.

For this reason, the center of gravity of the rotating member is displaced from the axis of the drive shaft 7, thereby causing vibration in the compressor itself. Particularly, when this compressor is used for an air conditioner for an automobile, the frequency of the compressor is reduced when the engine is idle. There is a drawback that the resonance frequency is caused to coincide with the rotation speed of the vehicle and cause the floor of the vehicle to vibrate.

Therefore, in the present invention, the rotation of a wobble plate type compressor that can prevent or reduce the vibration of the compressor itself by correcting the above-described drawback and correcting the displacement of the center of gravity of the entire rotating member according to the stroke amount is achieved. It is an object to provide a balance adjusting device.

(Means for Solving the Problems) However, the gist of the present invention is that a rotating member that transmits rotation of a drive shaft is swingably connected to a rotating member that transmits rotation of a drive shaft into a crank chamber formed inside, A rotatable member that supports a wobble plate connected to a piston via a rod and rotates with respect to the wobble plate, and the pressure in the crank chamber is adjusted by a pressure control valve to thereby control the wobble plate. A plurality of counterweights that rotate with the drive shaft and are relatively movable in the circumferential direction with respect to the drive shaft. An adjusting means is provided for moving the weight around the drive shaft in opposite directions according to a change in the swing angle of the wobble plate.

(Operation) Therefore, when the swing angle of the wobble plate is changed, the center of gravity of the entire rotating member is likely to be changed. In this case, the counterweight moves around the drive shaft to change the moment of inertia. Therefore, the center of rotation and the center of gravity of the entire rotating member can be made to coincide with each other, thereby achieving the above object.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIG. 1, a wobble plate type variable displacement compressor 1 has a bottomed cylindrical housing 2, a cylinder block 3 is fixed to an open end of the housing 2, and the housing 2 and one end of the cylinder block 3 are connected to each other. The crank chamber 4 is constituted by being surrounded by. A cylinder head 5 is fixed to the other end of the cylinder block 3 with a valve plate 6 interposed therebetween.

The drive shaft 7 includes the housing 2 and the cylinder block 3.
A power transmission rotating member 9 rotatably supported by the housing 2 via a radial bearing 8 is fixed to the drive shaft 7 in the crank chamber 4. A rotation member 11 for supporting a wobble plate 19, which will be described later, is also rotatably and swingably supported in the crank chamber 4 via a hinge ball 10 loosely fitted to the drive shaft 7. Have been. The supporting rotating member 11 is connected to the power transmitting rotating member 9 via a link mechanism.

The link mechanism slidably locks a pin 15 of an arm 14 provided on the supporting rotating member 11 with an elongated hole 13 of a lug plate 12 provided on the rotating member 9 for power transmission. The long hole 13 is provided so that the sliding of the pin 15 is not hindered from the maximum inclined state to the minimum inclined state of the rotating member 11, and in this embodiment, in particular, in the maximum inclined state, The distance between the pin 15 and the drive shaft 7 is minimized when the distance between the drive shaft 7 and the drive shaft 7 is maximized.

The rotation members 9 and 11 are provided with a balancer 9a on the opposite side of the link mechanism with respect to the drive shaft 7 of the power transmission rotation member 9 so that the center of gravity of the entire rotation member is the axis of the drive shaft 7. The shape is determined in advance so as to be located almost on the heart.

The wobble plate 19 is rotatably supported on the rotating member 11 for supporting the wobble plate in the crank chamber 4 via radial and thrust bearings 20 and 21, and is mounted on the housing 2 via the slider 22. The hinge ball 10 is engaged, and only swinging is allowed with the hinge ball 10 as a fulcrum.

A plurality of pistons 23 (for example, seven in the case of a seven-cylinder compressor) are connected to the wobble plate 19 via a rod 24. These pistons 23 are slidably inserted into cylinder bores 25 formed in the cylinder block 3, and the ends of the pistons 23 and the cylinder bores 25 are formed.
A compression chamber is formed in a space surrounded by the above.

When the piston 23 is in the suction stroke, the suction valve 26 is opened and the suction hole formed in the valve plate 6 is formed in the compression chamber.
When the piston 23 is in the discharge stroke, the discharge valve 29 is opened and the discharge hole 30 formed in the valve plate 6 is also opened.
Through a high-pressure chamber 31 defined in the cylinder head 5. The low-pressure chamber 28 and the high-pressure chamber 31 are connected to a suction port and a discharge port (not shown) formed in the cylinder head 5, respectively.

A cylindrical body 50 integrally formed with the hinge ball 10 is loosely fitted to the drive shaft 7, and two counterweights 51 and 52 described below are loosely fitted side by side to the cylindrical body 50. I have.

As shown in FIG. 2, the counter weights 51 and 52 are
It comprises annular ring portions 51a, 52a and weight portions 51b, 52b radially protruding from a part of the periphery of the ring portions 51a, 52a, and the center of gravity of each counter weight 51, 52 is set at the center of rotation (driving center). (On the axis 7 of the shaft 7). And, between the fixed ring 53 fixed near the tip of the drive shaft 7 and one of the counterweights 51,
The positioning rod 54 is inserted through the insertion holes 53a, 54a formed in the fixing ring 53 and the positioning member 54 and the arc-shaped holes 51c, 52c formed in the ring portions 51a, 52a of the counterweight with the positioning member 54 interposed. The two counterweights 51 and 52 are always maintained at a predetermined position in the axial direction of the drive shaft 7 by screwing the nut 56 into the nut.

The fixing means between the drive shaft 7 and the fixing ring 53 is formed by forming key grooves 7b and 53b in the drive shaft 7 and the fixing ring 53, and fitting the fixing ring 53 to the drive shaft 7 and then forming the key grooves 7b and 53b respectively. 53b
And the key 57 is fitted therein. The insertion hole 53a of the fixing ring 53 is on the same side as the link mechanism with respect to the drive shaft 7, and the assembly rod 55 is arranged on a plane including the link mechanism and the drive shaft 7. .

Arc-shaped holes 51c, 52c formed in counterweights 51, 52
For example, it is formed to have a length that makes a quarter of a circumference along the ring portions 51a, 52a from a position facing the center of the weight portions 51b, 52b. The counterweight 52 is formed counterclockwise from the fixing ring 53 in the arc-shaped hole 52c of the other counterweight 52 clockwise from the counterweight 52.

Thus, the counterweights 51 and 52 rotate with the rotation of the drive shaft 7 and the one of the counterweights 51 and 52 rotates.
Can be moved relative to the drive shaft in the range of 90 degrees counterclockwise from the link mechanism when viewed from the fixed ring 53, and the other counter weight 52 It can move relative to the drive shaft 7 in a clockwise range of 90 degrees.

The means for adjusting the relative position of the counterweights 51 and 52 with the drive shaft 7 is provided by forming two spiral grooves 58a and 58b in the cylindrical body 50 which are arranged back and forth in the axial direction, and one of the counterweights is formed in one of the spiral grooves 58a. A pin 59a that is inserted from the side surface of 51 through the insertion hole 51d and protrudes from the inner surface is engaged, and is inserted into the other spiral groove 58b from the side surface of the other counterweight 52 through the insertion hole 52d and from the inner surface. It is configured by engaging a protruding pin 59b. In this embodiment, the spiral grooves 58a, 58b start at a portion facing the position opposite to the weight portions 51b, 52b of the counterweight with respect to the drive shaft 7, and extend along the peripheral surface away from the hinge ball 10 therefrom. One helical groove 58a.
Are formed clockwise from the fixing ring 53, and the other spiral groove 58b is formed counterclockwise from the fixing ring 53. In the state where the hinge ball 10 is farthest from the counterweights 51 and 52, the pins 59a and 59b of the counterweight are located at the positions of the spiral grooves 58a and 58b that are farthest from the hinge ball 10, and in this state, the respective counterweights The weight portions 51b and 52b are configured to overlap in the axial direction.

Incidentally, 16a is a first elastic member interposed between the hinge ball 10 and the rotating member 9 for power transmission, 16b is
It is a second elastic member interposed between the cylinder 50 and the fixing ring 53, and presses the hinge ball 10 and the cylinder 50 from both sides in the axial direction.

In the compressor 1, a pressure control valve 32 is inserted and fixed in a control valve insertion hole 33 defined between the cylinder block 3 and the cylinder head 5. The control valve insertion hole 33 is
The suction chamber 35 is connected to the crank chamber 4 through a communication hole 34 formed in the cylinder block 3 through a pressure control valve 32.
Is connected to the low-pressure chamber 28 via a.

The pressure control valve 32 includes a valve body 36 for adjusting a communication state between the suction chamber 35 and the crank chamber 4, a pressure responsive member 37 for moving the valve body 36 according to the pressure in the suction chamber 35, Solenoid that forcibly moves 36 depending on the amount of electricity to electromagnetic coil 38
When the current flowing through the electromagnetic coil 38 increases and the magnetic force of the solenoid 39 increases, the valve element 36 moves in a direction to reduce the communication between the crank chamber 4 and the suction chamber 35.

When the current flowing through the electromagnetic coil 38 is small, the amount of gas leaking from the crank chamber 4 to the suction chamber 35 increases, the pressure in the crank chamber 4 decreases, and the force acting on the back surface of the piston 23 decreases. Plate 19 is a rotating member
With the hinge ball 10 as a fulcrum, the piston 11 rotates in a direction in which the swing angle increases, and the stroke of the piston 23, that is, the discharge capacity of the compressor 1 increases. In such a case, the hinge ball 10 approaches the rotating member 9 for power transmission, and the pins 59a, 59b of the respective counterweights 51, 52 are screwed into the spiral grooves 58.
The weights 51a and 52b of the counterweights 51 and 52 overlap in the axial direction on the side where the crank mechanism is located. Therefore, if only looking at the two counterweights 51 and 52, the center of gravity G is
As shown in FIG. 3 (a), it is shifted from the axis of the drive shaft 7.

On the other hand, when the current flowing through the electromagnetic coil 38 is large, the amount of gas leaking from the crank chamber 4 to the suction chamber 35 decreases, and the so-called blow-by gas leaks from between the piston 23 and the cylinder bore 25 to the crank chamber 4. Pressure increases. As the pressure in the crank chamber 4 increases, the force acting on the back surface of the piston 23 increases, and the wobble plate 19 rotates together with the rotating member 11 in a direction in which the swing angle decreases with the hinge ball 10 as a fulcrum. And
The stroke of the piston 23, that is, the displacement of the compressor 1 is reduced. In such cases, the hinge ball
10 moves away from the power transmitting rotary member 9, and the pins 59a, 59b of the respective counterweights 51, 52 are guided by the spiral grooves 58a, 58b and move to the opposite side to the link mechanism with respect to the drive shaft 7, The weight portions 51b, 52b of the counterweights 51, 52 rotate in opposite directions. For this reason, if only the two counterweights are viewed, each of the weight portions 51b and 52b
3B, the center of gravity G of the counterweight is located on the axis of the drive shaft 7 as shown in FIG. 3 (b).

For this reason, if the center of gravity of the entire rotating element including the rotating members 9 and 11 and the counterweights 51 and 52 is aligned with the axis of the drive shaft 7 in the maximum swing angle state of the wobble plate 19, In the state where the swing angle of the bull plate 19 is small, even if the center of gravity of the rotating members 9 and 11 moves to the opposite side to the link mechanism with respect to the drive shaft 7 as shown in FIG. By moving the center of gravity of 52, the center of gravity of the entire rotating element can be maintained at a position on or near the axis of the drive shaft 7, as shown by the dashed line in FIG. 4 (b). As a result, the vibration of the compressor caused by the deviation of the center of gravity can be suppressed.

(Effects of the Invention) As described above, according to the present invention, the displacement of the center of gravity of the entire rotating member from the center of rotation due to the change in the stroke of the piston, that is, the swing angle of the wobble plate, is controlled by the drive shaft. Is compensated by adjusting the amount of movement of the counterweight, which is relatively movable in the circumferential direction, so that the center of gravity of the entire rotating element and the center of rotation can be made substantially coincident regardless of the stroke amount. Vibration can be prevented or reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a wobble plate type compressor according to the present invention, FIG. 2 is an exploded perspective view showing a counterweight used in the compressor and its vicinity, and FIG. 3 is II in FIG. Shows a sectional view of the line,
(A) shows a case where the swing angle of the wobble plate is large (when the piston stroke is large), and (b) shows a case where the swing angle of the wobble plate is small (when the piston stroke is small). FIG. 4 is a characteristic diagram showing a balance state between a piston stroke and a rotating member, and FIG. 5 is a sectional view showing a conventional wobble plate type compressor. 1 ... Compressor, 4 ... Crankcase, 9,11 ... Rotating member, 19 ... Wobble plate, 23 ... Piston, 24 ...
Rods, 51, 52 …… Counter weights.

Claims (1)

(57) [Claims] A rotating member for transmitting rotation of a drive shaft, and a wobble plate connected to a piston via a rod, are supported in a crank chamber formed in the inside of the crank member. A wobble plate-type compressor that includes a rotating member that rotates with respect to the wobble plate and that varies a swing angle of the wobble plate by adjusting a pressure in the crank chamber with a pressure control valve. A plurality of counterweights that rotate with the drive shaft and are relatively movable in the circumferential direction with respect to the drive shaft are provided, and the plurality of counterweights are moved in accordance with a change in the swing angle of the wobble plate. A rotating balance adjusting device for a wobble plate compressor, comprising adjusting means for moving the periphery of a drive shaft in opposite directions.