JPH07247982A - Variable capacity vane compressor - Google Patents

Abstract

PURPOSE:To prevent an increase in clearance between a rotary plate and a cylinder while securing smooth rotation of the rotary plate. CONSTITUTION:An annular piston 54 is brought into contact with the anti- cylinder side end surface of a rotary plate 20 through a thrust bearing 53 to guide the discharge pressure to the anti-rotary plate side end surface of the annular piston 54 through a high pressure introducing passage. The discharge pressure is applied to the rotary plate 20 through the thrust bearing 53 to press the rotary plate 20 to the cylinder side, so that though a clearance between the rotary plate 20 and the cylinder 1 is decreased, frictional resistance which the rotary plate 20 receives is so small that the rotary plate 20 can be rotated smoothly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable capacity vane compressor capable of changing a discharge capacity.

[0002]

2. Description of the Related Art As a conventional variable displacement vane compressor, a rotor is rotatably housed in a cylinder in a housing, and a pair of side blocks are fixed to both ends of the cylinder. The space between the surface and the surface is divided into a plurality of compression chambers by a plurality of vanes, and the rotation of the rotor causes the suction ports and the discharge ports to communicate with the respective compression chambers alternately, and a vane for sucking, compressing and discharging the refrigerant gas In the compressor, a rotary plate that controls the maximum volume when the compression chamber is closed is rotatably interposed between the front side block and the rotor, and a spool is slidably mounted in the spool storage chamber of the front side block. A first pressure chamber for accommodating the spool, engaging a pin of the rotating plate with the spool, and introducing the refrigerant gas corresponding to the discharge pressure by the spool into the spool accommodating chamber; It is divided into a second pressure chamber into which oil corresponding to the discharge pressure is introduced via an opening / closing valve mechanism using pressure input, and a drive mechanism for driving the rotating plate by the pressure opposition between the two pressure chambers is provided. There is a structure in which a seal portion for separating high and low pressure regions from each other is provided between the front side block and the front side block, and a supply passage for guiding oil corresponding to the discharge pressure is communicated with the seal portion (JP-A-63-259190).

Generally, in this type of variable displacement vane compressor, when the gap between the rotary plate and the cylinder becomes large, the blow-by gas leaking from the compression chamber of the cylinder through the gap increases and the compression efficiency (volume efficiency ηv) is increased. It is necessary to press the rotary plate to the cylinder side, because it lowers, the back pressure of the vane acting on the vane decreases, chattering of the vane occurs, and noise is generated due to looseness of the rotary plate.

[0004]

In the variable capacity vane compressor described above, in order to prevent the refrigerant gas equivalent to the discharge pressure introduced into the first pressure chamber from leaking, the rotary plate and the front side block are prevented. A seal part (annular sealing recess and seal ring mounted in this recess) that separates and shuts off both the high pressure and low pressure regions is provided between and, and lubricating oil equivalent to the discharge pressure is supplied to the seal. ing. As a result, a high pressure equivalent to the discharge pressure is directly applied to the rotary plate by the lubricating oil, and the rotary plate is pressed against the cylinder side.

However, in order to sufficiently prevent the leakage of the refrigerant gas corresponding to the discharge pressure introduced into the first pressure chamber by the seal ring and the lubricating oil, the lubricating oil is provided between the seal ring and the rotary plate. Since it is necessary to press the seal ring against the rotating plate side so that it does not leak from the
The frictional force between the seal ring and the rotating plate causes a great resistance to the rotation of the rotating plate, and there is a problem that the rotating plate cannot rotate smoothly.

The present invention has been made in view of the above circumstances, and its object is to make it possible to prevent the increase of the gap between the rotary plate and the cylinder while ensuring the smooth rotation of the rotary plate. The object is to provide a capacity vane compressor.

[0007]

In order to solve the above-mentioned problems, a variable capacity vane compressor according to the invention of claim 1 is
A cylinder having an inner surface of an approximately elliptical diameter, a rotor rotatably housed in the cylinder, a plurality of vanes slidably inserted in vane grooves of the rotor, and both end surfaces of the cylinder. A pair of fixed side blocks,
A rotary plate rotatably housed in the cylinder side concave portion of the one side block between a partial operating position that minimizes the discharge capacity and a full operating position that maximizes the discharge capacity, and the rotation plate. A variable capacity vane compressor including a drive mechanism that rotates a plate in accordance with suction pressure of a suction chamber formed in one of the side blocks,
An annular pressing member provided in the one side block and abutting against the end surface of the rotary plate on the side opposite to the cylinder via a thrust bearing, and a high-pressure introduction passage for guiding high pressure to the end surface of the press member on the side opposite to the rotary plate. ing.

In the variable capacity vane compressor according to the second aspect of the present invention, the high pressure is the discharge pressure discharged from the compression chamber in the cylinder.

Further, in the variable capacity vane compressor of the third aspect of the invention, the discharge pressure introducing chamber is provided in the middle of the high pressure introducing passage.

[0010]

As described above, the annular pressing member is brought into contact with the end surface of the rotating plate on the side opposite to the cylinder via the thrust bearing, and high pressure is introduced to the end surface of the pressing member on the side opposite to the rotating plate through the high pressure introducing passage. The high pressure acts on the rotary plate via the thrust bearing to press the rotary plate toward the cylinder side, the gap between the rotary plate and the cylinder becomes small, and the frictional resistance received by the rotary plate is small, so that the rotary plate can smoothly rotate.

Further, if the discharge pressure discharged from the compression chamber in the cylinder as high pressure is guided to the end surface of the pressing member on the side opposite to the rotary plate, it acts on the rotary plate via the thrust bearing even during partial operation. Since the pressure does not drop significantly and the force pressing the rotary plate against the cylinder is kept high, the gap between the rotary plate and the cylinder is kept small.

Further, if the discharge pressure introducing chamber is provided in the middle of the high pressure introducing passage, the pressure fluctuation of the discharge pressure sent from the compression chamber through the high pressure introducing passage to the end surface of the pressing member on the side opposite to the rotating plate causes the discharge pressure to change. Since it is damped by the introduction chamber, pulsation is reduced, and a substantially constant discharge pressure is introduced to the end surface of the pressing member on the side opposite to the rotation plate through the high pressure introduction passage regardless of the change in volume.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a vertical sectional view showing a variable capacity vane compressor according to an embodiment of the present invention. This variable capacity vane compressor is a cylinder 1 having a substantially elliptical inner peripheral surface 1a, a front side block 2 fixed to a front end surface 1b of the cylinder 1, and a front side block 2 fixed to an end surface. , Front side block 2
A front head 4 that forms a discharge chamber 3 between them, a rear side block 5 that is fixed to the rear end surface 1c of the cylinder 1, and a suction chamber 6 that is fixed to the end surface of the rear side block 5 And a rotor 8 rotatably housed in the cylinder 1.
And a rotation shaft 9 of the rotor 8. The rotating shaft 9
The front side block 2 and the rear side block 5 are rotatably supported by radial bearings 10 and 11, respectively.

A refrigerant gas discharge port 4a is formed in the front head 4, and a refrigerant gas suction port 7a is formed in the rear head 7. The discharge port 4a communicates with the discharge chamber 3, and the suction port 7a communicates with the suction chamber 6.

Two compression chambers 12 are formed between the inner peripheral surface 1a of the cylinder 1 and the outer peripheral surface of the rotor 8 at substantially symmetrical positions in the circumferential direction. The rotor 8 is provided with a plurality of vane grooves 8a, and the vanes 13 are slidably inserted in the vane grooves 8a.

As shown in FIG. 1, the outer peripheral wall of the cylinder 1 has two discharge ports 14 corresponding to the two compression chambers 12.
Are provided at substantially symmetrical positions in the circumferential direction (only one discharge port 14 is visible in FIG. 1). The discharge port 14 is provided with a discharge valve 17. Further, the outer peripheral wall of the cylinder 1 and the discharge valve cover 1 fixed to the outer peripheral wall
6, a discharge space 17 into which the refrigerant gas discharged from each discharge port 14 flows is formed. The discharge space 17 communicates with the discharge chamber 3 via a discharge passage 18 provided in the front side block 2.

FIG. 6 is an end view of the rear side block as seen in the direction of arrow B in FIG. 1, and FIG. 7 is a view as seen in the direction of arrow C in FIG.

As shown in FIG. 6, an annular recess 5a (cylinder recess) is provided on the cylinder side end surface of the rear side block 5, and the rotary plate 20 is housed in the annular recess 5a. The rotary plate 20 is rotated by a drive mechanism 30 described later.

The rear side block 5 is provided with two suction holes 5b at positions displaced by approximately 180 ° in the circumferential direction. On the other hand, the rotating plate 20 has approximately 1 in the circumferential direction.
Two notches 20a are provided at positions shifted by 80 °. Then, the refrigerant gas in the suction chamber 6 is sucked into each compression chamber 12 in the cylinder 1 through each suction hole 5b of the rear side block 5 and each notch 20a of the rotary plate 20.

Rotating plate 2 housed in annular recess 5a
0 is a part that delays the end position of the suction stroke (the start position of the compression stroke) in which the refrigerant gas is sucked into each compression chamber 12 through each suction hole 5b and each notch 20a to minimize the discharge capacity. It is possible to rotate between the operating position and the entire operating position where the end position of the suction stroke is the earliest and the discharge capacity is maximized, and the discharge capacity can be continuously changed.

FIG. 4 is a sectional view taken along the line EE of FIG.
FIG. 4 is a sectional view taken along the line D-D in FIG. 3.

The drive mechanism 30 is slidably accommodated in the cylinder chamber 5c of the rear side block 5 and rotates the rotary plate 20 via a connecting pin 31 (see FIG. 1) fixed to the rotary plate 20. A piston 32 to
The pressure adjusting valve mechanism 33 controls the reciprocating motion of the piston 32. The connecting pin 31 projects toward the rear head 7, and the tip of the connecting pin 31 is fitted into the annular groove 32a of the piston 32 as shown in FIGS. It is slidably fitted in the groove 5d. As a result, when the piston 32 reciprocates in the cylinder chamber 5c, the tip of the connecting pin 31 slides in the arc-shaped guide groove 5d, and the rotary plate 20 rotates.

As shown in FIG. 4, a spring guide member 33 having a rod-shaped spring guide portion 33a is inserted into one end of the cylinder chamber 5c, and one end of the cylinder chamber 5c has a spring receiving portion 33b of the spring guide member 33. And is sealed by an O-ring 34. The spring receiving portion 33b is fixed to the rear side block 5 by a pin 35. On the other hand, the other end of the cylinder chamber 5c is sealed by the plug 36 and the O-ring 37. The plug 36 is fixed to the rear side block 5 by a pin 38.

At one end of the piston 32, the suction chamber 6
A low pressure chamber 39 into which the suction pressure Ps is introduced is formed. On the other end side of the piston 32, a high pressure chamber 40 into which a control pressure Pc described later is introduced is formed. Piston 32
Is a spring 41 interposed between one end of the piston 32 and the spring receiving portion 33b of the spring guide member 33, and the low pressure chamber 3
The suction pressure Ps in 9 causes the discharge volume to be minimized to a partial operating position side (to the left in FIG. 4), and the control pressure Pc in the high pressure chamber 40 maximizes the discharge volume. It is pressed toward the operating position (to the right in FIG. 4). As a result, the piston 32 reciprocates in the cylinder chamber 5c according to the change in the control pressure Pc. That is,
In the piston 32, the control pressure Pc is the suction pressure Ps and the spring 41.
When the control pressure Pc is smaller than the pressing force, it is partially displaced to the full operating position side.

The pressure adjusting valve mechanism 33 controls the control pressure Pc introduced into the high pressure chamber 40 according to the suction pressure Ps of the suction chamber 6.
As shown in FIG. 5, a ball valve 45 that opens and closes a communication passage between the control pressure chamber 43 and the bellows chamber 44, and a spring 55 that urges the ball valve 45 in the valve closing direction.
And the plunger 50 for urging the ball valve 45 in the valve closing direction by the discharge pressure Pd introduced through the high pressure introduction passage 47.
And the bellows chamber 4 into which the suction pressure Ps is introduced from the suction chamber 6.
4, a bellows 46 that expands and contracts according to changes in the suction pressure Ps, and a rod 51 that is fixed to the free end of the bellows 46 and that pushes the ball valve 45 in the opening direction when the bellows 46 extends. There is.

The high-pressure introducing passage 47 includes a communicating passage 47a formed in the cylinder 1, a port 47b formed in the rear side block 5, a communicating passage 47c, a discharge pressure introducing chamber 47d having a large volume, and a communicating passage 47e. It is configured. The communication passage 47a is in direct communication with the discharge space 17 (see FIG. 1) into which the refrigerant gas discharged from the compression chamber 12 flows. The communication passage 47e communicates with the control pressure chamber 43 through the orifice 42, and the control gas Pc is formed by introducing the refrigerant gas discharged from the compression chamber 12 through the orifice 42.

Further, the control pressure chamber 43 communicates with the high pressure chamber 40 (see FIG. 4) through a communication passage 48, and the control pressure chamber 43
The control pressure Pc formed therein is introduced into the high pressure chamber 40 via the communication passage 48.

When the suction pressure Ps becomes lower than a predetermined value, the bellows 46 extends from the state shown in FIG. 5 to open the ball valve 45, whereby the control pressure Pc in the control pressure chamber 43 and the high pressure chamber 40 decreases, and When the pressure Ps becomes higher than a predetermined value, the bellows 46 contracts to close the ball valve 45 as shown in FIG. 5, whereby the control pressure Pc in the control pressure chamber 43 and the high pressure chamber 40 rises. The predetermined value can be adjusted by the adjusting screw 52.

The annular recess 5 of the rear side block 5
Inside the annular recess 5e formed on the bottom surface of a, the end surface 2 on the side opposite to the cylinder side of the rotary plate 20 is inserted through the thrust bearing 53.
Annular piston (annular pressing member) that abuts 0b
54 are accommodated.

As shown in FIG. 2, the bottom surface 5 of the annular recess 5e is
f and the end surface 5 of the annular piston 54 on the side opposite to the rotating plate
4a, a pressure chamber 60 is formed, and the discharge pressure Pd is introduced into the pressure chamber 60 via the communication passage 55. The communication passage 55 is provided in the rear side block 5, and one end of the communication passage 55 has a discharge pressure introducing chamber 47d (see FIG.
(Refer to FIG. 3), the other end of the communication passage 55 opens to the bottom surface 5f of the annular recess 5e. This communication passage 55 and port 4
The refrigerant gas discharged from the pressure chamber 12 is supplied to the pressure chamber 60 by the 7b, the communication passage 47, and the discharge pressure introduction chamber 47d (to the end face 54a of the annular piston 54 on the side opposite to the rotating plate).
A high-pressure introduction passage 61 for guiding is constructed.

In order to prevent the discharge pressure Pd in the pressure chamber 60 from leaking to the low pressure side (suction chamber 6 side), O-rings 56 and 57 are provided between the annular piston 54 and the annular recess 5e. There is. Also, the annular piston 5
A female screw 54b is formed on the connector 4 to facilitate removal from the annular recess 5e.

Next, the operation of the variable displacement vane compressor of this embodiment will be described.

At start-up, the control pressure Pc is low, the piston 32 is in the partially operating position side shown in FIG. 4, and the rotary plate 20 is also in the partially operating position side, whereby the compressor is operated with a small capacity. .

When the suction pressure Ps becomes higher than a predetermined value, the bellows 46 contracts and the ball valve 45 closes as shown in FIG. 5, whereby the control pressure Pc in the control pressure chamber 43 and the high pressure chamber 40 rises. , The piston 32 is displaced from the partial operating position side to the full operating position side (displaced to the right in FIG. 4). For example,
The piston 32 is displaced from the partial operating position side shown in FIG. 8 to the intermediate position shown in FIG. 7. This displacement is transmitted to the rotary plate 20 via the connecting pin 31, and the rotary plate 20 rotates from the partially operating position side to the fully operating position side, thereby increasing the discharge capacity.

When the suction pressure Ps becomes lower than a predetermined value, the bellows 46 extends from the state shown in FIG. 5 and the ball valve 45 opens,
As a result, the control pressure P in the control pressure chamber 43 and the high pressure chamber 40 is increased.
c is lowered, and the piston 32 is displaced from the full operating position side to the partial operating position side (this displacement on the left side in FIG. 4 is transmitted to the rotary plate 20 via the connecting pin 31, and the rotary plate 20 is moved to the full operational position side. To a part of the operating position side, which reduces the discharge capacity).

In this manner, the discharge capacity is continuously variably controlled by rotating the rotary plate 20 according to the suction pressure Ps.

According to the variable displacement vane type compressor of this embodiment, the annular piston 54 is housed in the annular recess 5e of the rear side block 5 and the end face 20b of the rotary plate 20 on the side opposite to the cylinder side is thrust via the thrust bearing 53. The discharge pressure Pd is introduced to the end face 54a of the annular piston 54 opposite to the rotary plate, and the discharge pressure Pd acts on the rotary plate 20 via the thrust bearing 53 to press the rotary plate 20 toward the cylinder 1 side. The frictional resistance that the rotary plate receives is small, and it is possible to prevent the increase of the gap between the rotary plate and the cylinder while ensuring smooth rotation of the rotary plate.

Further, the refrigerant gas discharged from the pressure chamber 12 in the cylinder 1 is supplied to the pressure chamber 60 (annular piston 5
No. 4, the discharge pressure introducing chamber 47d having a large volume is provided in the middle of the high pressure introducing passage 61 leading to the end face 54a on the anti-rotation plate side. Therefore, the anti-rotation of the annular piston 54 from the compression chamber 12 through the high pressure introducing passage 61. Plate side end surface 54
The pressure fluctuation of the refrigerant gas sent to a is caused by the discharge pressure introducing chamber 47d.
The pulsation is reduced by this, and a substantially constant discharge pressure Pd is maintained regardless of the change in the volume.
Since it is supplied to the end face 54a of the annular piston 54 on the side opposite to the rotating plate 2 via the No. 1, the rotating plate 2 is secured regardless of the change in capacity while ensuring smooth rotation of the rotating plate 20.
The gap between 0 and the cylinder 1 can be made almost constant.

[0040]

As described above, according to the variable displacement vane compressor of the present invention, the annular pressing member is brought into contact with the end surface of the rotary plate on the side opposite to the cylinder via the thrust bearing and pressed through the high pressure introducing passage. Since high pressure is introduced to the end face of the member opposite to the rotating plate, the high pressure acts on the rotating plate via the thrust bearing to press the rotating plate toward the cylinder side and prevent the gap between the rotating plate and the cylinder from increasing. Moreover, since the frictional resistance applied to the rotating plate is small, the rotating plate can smoothly rotate.

Further, if the discharge pressure discharged from the compression chamber in the cylinder as high pressure is guided to the end face of the pressing member on the side opposite to the rotating plate, it acts on the rotating plate via the thrust bearing even during partial operation. Since the pressure does not drop significantly and the force pressing the rotary plate against the cylinder is kept high, the gap between the rotary plate and the cylinder is kept small.

Further, if the discharge pressure introducing chamber is provided in the middle of the high pressure introducing passage, the pressure fluctuation of the refrigerant gas sent from the compression chamber through the high pressure introducing passage to the end surface of the pressing member on the side opposite to the rotating plate causes the discharge pressure to change. Since it is damped by the introduction chamber, pulsation is reduced, and a substantially constant discharge pressure is introduced to the end surface of the pressing member opposite to the rotation plate through the high-pressure introduction passage regardless of volume change, and the force that presses the rotation plate on the cylinder is constant. To be kept.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a variable capacity vane compressor according to an embodiment of the present invention.

FIG. 2 is a partially enlarged view of FIG.

FIG. 3 is a view on arrow A in FIG.

4 is a cross-sectional view taken along the line EE of FIG.

5 is a cross-sectional view taken along the line DD of FIG.

FIG. 6 is an end view of the rear side block seen in the direction of arrow B in FIG.

FIG. 7 is a view taken in the direction of arrow C in FIG. 1, showing a state in which the piston is partly in the operating position side.

FIG. 8 is a view similar to FIG. 7, showing a state in which the piston is in the vicinity of an intermediate position.

[Explanation of symbols]

 1 Cylinder 1a Inner Surface 3 Discharge Chamber 5 Rear Side Block (One Side Block) 5a Cylinder Side Recess 5f Bottom 6 Suction Chamber 7 Rear Head 8 Rotor 8a Vane Groove 12 Compression Chamber 20 Rotating Plate 20b Opposite Cylinder Side 30 Drive Mechanism 47d Discharge Pressure introducing chamber 53 Thrust bearing 54 Annular piston (pressing member) 54a Counter-rotating piston side end face 60 Pressure chamber 61 High pressure introducing passage

Claims (3)

[Claims] 1. A cylinder having an inner peripheral surface having a substantially elliptical diameter, and a rotor rotatably housed in the cylinder.
The plurality of vanes slidably inserted in the vane grooves of the rotor, the pair of side blocks fixed to both end surfaces of the cylinder, and the cylinder side concave portion of the one side block have a minimum discharge capacity. And a rotating plate housed so as to be rotatable between a partial operating position and a full operating position that maximizes the discharge capacity, and the rotating plate of the suction chamber formed in one of the side blocks. In a variable displacement vane compressor provided with a drive mechanism that rotates in accordance with suction pressure, a ring-shaped compressor that is provided on the one side block and abuts an end surface of the rotating plate on the side opposite to the cylinder via a thrust bearing. A variable capacity vane compressor comprising: a pressing member; and a high-pressure introducing passage for guiding a high pressure to an end surface of the pressing member on the side opposite to the rotating plate. 2. The variable displacement vane compressor according to claim 1, wherein the high pressure is a discharge pressure discharged from a compression chamber in the cylinder. 3. The variable displacement vane compressor according to claim 2, wherein a discharge pressure introducing chamber is provided in the high pressure introducing passage.