JPS62265491A - Vane type compressor - Google Patents

Abstract

PURPOSE:To simplify structure, by a method wherein a control member for the open angle of the bypass port of a side block is motioned through utilization of the pressure of a compressor, and a communicating passage running between a second chamber on the high pressure side and a low pressure chamber is controlled by means of an on-off valve having a hysteresis preventing member. CONSTITUTION:A control member 24 for the bypass port of a side block 8 is controlled through the pressure of a pressure-operated chamber. A second chamber 272 on the high pressure side is communicated to a suction chamber 17 through a communicating passage 32, and the communicating passage is controlled by means of an on-off valve mechanism 33 having a plunger 39 serving as a hysteresis preventing member. This constitution simplifies structure of a variable capacity control mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a vane compressor used as a refrigerant compressor for, for example, an automobile air conditioner.

(Prior art and its problems) Conventionally, a so-called variable displacement vane type compressor, in which the capacity of the vane type compressor can be controlled by adjusting the suction amount of gas to be compressed, was developed in Utility Model Application No. 55-2000. The number is publicly known.

Such a conventional vane type compressor has an arc-shaped slot bored through an end plate on the side of the suction port provided in the lower part of the cylinder, and a throttle plate is slidably fitted into the slot. The throttle plate is slid within the slot and the length of the suction port is restricted at the tip thereof, thereby changing the compression start position and varying the discharge capacity. Further, one end of a swing lever is connected to the throttle plate via a shaft, the swing lever is pivotally supported by a support shaft fixed to the end plate, and an actuator connected to the other end is connected to the throttle plate. The throttle plate is slidably displaced by rotating the swing lever.

Therefore, since the actuator, which is the driving means, deflects the throttle plate, which is the control member of the suction port, through the swing lever, the hysteresis of the control member is large, and the processing and assembly are complicated. was there.

In addition, as a vane type compressor with reduced hysteresis of the control member described above, the present applicant filed a Japanese patent application No. 60-719.
No. 84 has been filed. The vane type compressor according to the application includes a cam ring whose both end faces are closed with side blocks, a rotor rotatably disposed within the cam ring, and a rotor slidably fitted into a vane groove of the rotor. comprising a plurality of vanes, a control member detachably attached to the suction port of the - side side block, and a driving means for driving the control member, and defined by the side block, the rotor, and the vane. In the vane type compressor, the fluid is compressed by changing the volume of the compression chamber, and the discharge capacity can be variably controlled by changing the compression start position of the suction port using the control member, A toothed portion for being driven is carved on the control member, and a toothed portion that meshes with the toothed portion is provided on the output shaft of the driving means, so that the control member is directly driven by the driving means. .

However, since this vane type compressor has a step motor built into the housing as a driving means, it requires a large storage space, has a complicated structure, and is expensive. .

(Object of the Invention) The present invention has been made in view of the above circumstances, and is a vane type compressor equipped with a variable capacity control mechanism that has a simple and compact structure, is low in cost, and has highly reliable control that prevents hysteresis. The purpose is to provide

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention includes a cam ring whose both sides are closed with side blocks, a rotor rotatably disposed within the cam ring, and a rotor that is rotatably disposed within the cam ring. A vane type compressor is provided with a vane slidably fitted in a vane groove of the side block, the cam ring, the rotor, and the vane, and compresses fluid by changing the volume of a cavity defined by the side block, the cam ring, the rotor, and the vane. , a bypass port provided in the side block having the suction port of both the side blocks; a pressure operating chamber provided in the side block having the suction port and communicating with the low pressure chamber side and the high pressure chamber side; The pressure working chamber is slidably fitted in the pressure working chamber so as to airtightly divide the pressure working chamber into a first chamber communicating with the low pressure chamber side and a second chamber communicating with the high pressure chamber side. a control member that has a pressure receiving part and controls the opening angle of the bypass port; a biasing member that urges the control member in a direction in which the opening angle of the bypass port increases; and the second chamber and the low pressure chamber side. and a communication path disposed in the communication path that closes the communication path when the pressure on the low pressure chamber side is above a predetermined value and when the pressure on the low pressure chamber side is below a predetermined value. and an opening/closing valve mechanism having a hysteresis prevention member that always urges the valve element in the valve closing direction by pressure on the high pressure chamber side.
The control member rotates in accordance with the differential pressure between the first chamber and the second chamber to control the opening angle of the bypass port, thereby controlling the compression start timing and variably controlling the discharge volume. It is characterized by

(Example) Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings.

FIG. 1 is a partially cutaway side view of a vane compressor according to the present invention. In the figure, 1 is a housing, which is a cylindrical case 2 with an open end surface, and a cylindrical case 2 with an open end surface on one end surface of the case 2. It consists of a front head 3 attached with bolts (not shown) so as to be closed. A discharge port 4 for refrigerant gas, which is a heat medium, is provided on the upper surface of the rear side of the case 2, and an inlet port 5 for refrigerant gas is provided on the upper surface of the front head 3, respectively. The discharge port 4 and the suction port 5 communicate with a discharge chamber and a suction chamber, respectively, which will be described later.

A pump body 6 is housed inside the housing 1. The pump body 6 includes a cam ring 7, a front side block 8 and a rear side block 9 attached to both open ends of the cam ring 7 so as to close the opening surfaces.
The main components are a circular rotor 1o rotatably housed inside the cam ring 7 and a rotating shaft 11 of the rotor 10, and the rotating shaft 11 is connected to each bearing provided on both side blocks 8.9. (Only the front side block 8 side is shown.) It is rotatably supported at 12.

The inner circumferential surface of the cam ring 7 has an elliptical shape as shown in FIG. A void chamber 13.13 is defined.

A plurality (for example, four) of vane grooves 14 are provided in the rotor 10 at equal intervals in the circumferential direction along the radial direction of the rotor 10,
Vanes 151 to 15. are fitted in such a way that they can appear and retract freely along the radial direction.

The front side block 8 is provided with suction ports 16, 16 symmetrically offset by 180 degrees in the circumferential direction (see FIGS. 2 to 7). These suction ports 16.16 are located in the cavity 1 divided by the vanes 151-15°.
It is placed at the position where the volume of No. 3 is maximum. The suction ports 16.16 pass through the front side block 8 in the thickness direction, and through these suction ports 16,
A suction chamber (low-pressure side chamber) 17 between the front head 3 and the front side block 8 and the gap chamber 13 communicate with each other.

Discharge ports 18 and 18 are provided on both side peripheral walls of the cam ring 7.
are provided, and the discharge chamber (high pressure side chamber) 19 in the case 2 and the void chamber 13 communicate with each other through these discharge ports 18 and 18 as shown in FIG. A discharge valve 20 and a discharge valve stop 21 are respectively provided.

As shown in FIG. 7, the front side block 8 is provided with an annular recess 22 on its one side (rotor 1o side) surface, and an arc-shaped bypass port 2 is provided in the recess 22.
3.23 are provided symmetrically and offset by 180 degrees in the circumferential direction, and the suction chamber 17 and the void chamber 13 communicate with each other via these bypass ports 23. Furthermore, a ring-shaped control member 24 for controlling the opening angle of the bypass port 23.23 is fitted in the recess 22 so as to be rotatable in forward and reverse directions.

The outer circumferential edge of the control member 24 is provided with an arc-shaped notch 25.25 symmetrically offset by 180 degrees in the circumferential direction. Further, on one side of the control member 24, 18
A protruding piece-shaped pressure receiving part 26.26 is integrally provided and symmetrically offset by 0 degrees. These pressure receiving parts 26.26 are slidably fitted into an arcuate pressure operating chamber 27.27 provided continuously with the bypass port 2:l 23. The inside of these pressure working chambers 27 is divided into a first chamber 27□ and a second chamber 27□ by the pressure receiving section 26, and the first chamber 271 is connected to the suction chamber 17 through the suction port 16 and the bypass port 23. In addition, the second chambers 27□ communicate with the discharge chamber 19 via orifices 28, respectively. The one second chamber 272 and the other second chamber 27□ communicate with each other via the communication hole 29, and the orifice 28 is interposed between the one second chamber 27□ and the discharge chamber 19. It is equipped.

A sealing member 30 having a special shape as shown in FIG. 7 is installed over the center of one side of the control member 24 and the end face of the pressure receiving portion 26. As shown in FIG. The sealing member 30 allows a gap between the first chamber 27□ and the second chamber 27□ as shown in FIG. 8 and the center portions of the annular recesses 22 are hermetically sealed.

The control member 24 uses a coil spring 31, which is a biasing member, to control the bypass port 23 in a direction (
(counterclockwise in FIG. 5). This coil spring 31 is fitted onto the outer circumferential side of the central boss portion 8a of the front side block 8 that extends toward the suction chamber 17 side. This coil spring 31 has one end connected to the central boss portion 8a and the other end connected to the control member 24, respectively.

The other second chamber 27□ communicates with the suction chamber 17 via a communication passage 32 as shown in FIGS. 1 and 3,
The communication passage 32 is provided with an on-off valve mechanism 33. The opening/closing valve mechanism 33 opens and closes in response to the pressure Ps on the suction chamber 17 side (low pressure chamber side), and as shown in FIG. 8, includes a bellows 34, a case 35, a ball valve body 36, It consists of a spring 37 that urges the ball valve body 36 in the valve closing direction and a plunger 39. A rod 34a is attached to one end of the bellows 34, and the rod 34a is attached to the case 35.
It is slidably inserted into a communication passage 32a bored in the ball valve body 36, and its tip is in contact with one side of the ball valve body 36. Further, the plunger 39 is provided to prevent hysteresis of the opening/closing valve mechanism 33 and to smoothly open and close the valve mechanism 33, and is slidably inserted into a through hole 40 formed in the front side block 8. Since the discharge pressure (high pressure chamber side pressure) Pd of the discharge chamber 19 is introduced into the through hole 40 through the clearance between the front side block 8 and the cam ring 7,
The plunger 39 is always urged toward the ball valve body 36 by its discharge pressure Pd, and its tip surface is in contact with the ball valve body 36. Note that the seat area S of the ball valve body 36 and the area S' of the end surface (pressure receiving surface) of the plunger 39 are formed to be approximately the same. When the pressure Ps on the side of the suction chamber 17 is above a predetermined value, the bellows 34 is in a contracted state, and the ball valve body 36 closes the communication passage 32a by the urging force of the spring 37 and the plunger 39. Further, when the pressure Ps on the side of the suction chamber 17 is below a predetermined value, the bellows 34 is expanded and the rod 34a at the tip thereof is expanded.
As a result, the ball valve body 36 is pressed against the biasing force of the spring 37 and the plunger 39 to open the communication passage 32a. There is an O between the case 35 and the front side block 8.
A ring 38 is interposed.

(Operation) Next, the operation of the vane type compressor of the present invention having the above structure will be explained.

When the rotor 10 rotates clockwise in FIG. 2 as the rotating shaft 11 is rotated in relation to the engine of the vehicle, the vanes 15. ~
15. protrudes in the radial direction from the vanes 1114 due to centrifugal force and vane back pressure, rotates together with the rotor 10 while its tip surface slides on the inner peripheral surface of the cam ring 8, and each vane is divided by 151 to 15 degrees. In the suction stroke to expand the volume of the cavity 13, refrigerant gas, which is a heat medium, is sucked into the cavity 13 through the suction port 16, and the volume of the cavity 13 is increased.
The refrigerant gas is compressed in the compression stroke to reduce the volume of the refrigerant.

In the discharge stroke at the end of the compression stroke, the discharge valve 20 is opened by the pressure of the compressed refrigerant gas, and the compressed refrigerant gas is delivered to the discharge port 1.
8, the discharge chamber 19 and the discharge port 4 are sequentially supplied to a heat exchange circuit of an air conditioner (not shown).

When such a compressor operates, the pressure Ps in the suction chamber 17, which is on the low pressure side, is introduced into the first chamber 271° 271 of both pressure working chambers 27.27 through the suction port 16, and the high pressure The pressure Pd in the discharge chamber 19, which is the side, flows through the orifice 28 and the communication hole 29 to both pressure working chambers 27.
．． 27 into the second chambers 27□, 272. Therefore, the sum of the pressure in the first chamber 271 and the biasing force of the coil spring 31 (the force that presses the control member 24 in the direction in which the opening angle of the bypass port 23 becomes larger, that is, the arrow B in FIG.
the pressure in the second chamber 27□ (the force that presses the control member 24 in the direction that reduces the opening angle of the bypass port 23, that is, the force that rotates it in the direction of arrow A in FIG. 5). ) The control member 24 rotates in response to the differential pressure between the bypass port 23 and the opening angle of the bypass port 23, thereby controlling the compression start timing and controlling the discharge capacity.

That is, during low-speed operation of the compressor, the pressure of refrigerant gas in the suction chamber 17 (suction pressure Ps) is relatively high, so the bellows 34 of the on-off valve mechanism 33 contracts, causing the ball valve body 36 to contract.
is in a state where the communication passage 32a is blocked by 171, and the second chamber 2
7 overcomes the sum of the pressure in the first chamber 271 and the biasing force of the coil spring 31, and the control member 24 is rotated to the rotation limit position in the direction of arrow A in FIG. motion is maintained,
The entire bypass port 23 is closed by the control member 24 as shown by the two-dot chain line in FIG. 5 (the opening angle is zero).

Therefore, all of the refrigerant gas sent into the gap chamber 13 from the suction port 16 is compressed and discharged, so that the discharge capacity of the compressor is maximized and the compressor is in full operation.

Next, when the compressor enters a high-speed operation state, the suction pressure Ps in the suction chamber 17 decreases, so the bellows 34 of the on-off valve mechanism 33 expands, and the rod 34a moves the ball valve body 36 between the spring 37 and the plunger 39. As the communication passage 32a opens to open the valve by pressing against the force, the pressure in the second chamber 27□ leaks into the suction chamber 17 on the low pressure side via the communication passage 32.32a. As a result, the pressure inside the second chamber 27□ decreases, and as a result, the control member 24 rotates in the direction of arrow B in FIG. As a result, the bypass port 23 opens as shown by the solid line in FIG. Therefore, since the refrigerant gas sent from the port 16 into the cavity chamber 13 passes through the bypass port 23 and leaks to the suction chamber 17, the compression start time is delayed by the amount that the bypass port 23 opens, and the refrigerant gas in the cavity chamber 13 Since the amount of compressed gas decreases, the discharge capacity of the compressor decreases and the compressor becomes partially operational.

Note that the opening angle of the bypass port 23 is the same as that of the first chamber 2.
71 and the force of the sum of the spring 37.

It is determined when the pressure in the second chamber 27□ is balanced, and the pressure in the suction chamber 17 (suction pressure P
Since the rotational position of the control member 24 changes continuously in response to changes in s), continuous variable displacement control of the compressor is possible. Further, although the pressure of the discharge chamber 19, that is, the discharge pressure Pd, is introduced into the second chamber 27□, the present invention is not limited to this.
5. - 15 in the protrusion direction, that is, vane back pressure may be introduced.

Next, the action of the plunger 39 provided in the on-off valve mechanism 33 for preventing hysteresis will be explained. First, considering the case where the plunger 39 is not provided, the biasing force of the spring 37 and the pressure in the second chamber 272 of the pressure operating chamber 27 (referred to as Pc) are in the direction of closing the ball valve body 36. The power of peace is at work. However, since the pressure Pc in the second chamber 27□ is a value that constantly fluctuates (for example, 3 to 14 kg/1ffl), the bellows 34 expands and contracts in response to changes in the suction pressure Ps, and the ball valve body 36 opens and closes. During operation, the ball valve body 36 is difficult to open and close in a constant regular manner, and hysteresis is likely to occur.

Therefore, when the plunger 39 is provided, the plunger 3
9 always presses the ball valve element 36 in the valve closing direction by the discharge pressure Pd, so the ball valve element 36 is not affected by fluctuations in the pressure Pc.

This is because the discharge pressure Pd is always approximately constant and Pd
This is because the ball valve body 36 is always influenced by the higher pressure, that is, Pd, and is not affected by fluctuations in the value of Pc, since the relationship is ≧Pc. Therefore, the force that the ball valve element 36 receives in the valve closing direction becomes the sum of the biasing force of the spring 37 and the discharge pressure Pct and is always constant, so the opening/closing state is always constant and hysteresis is eliminated. prevention and improved controllability.

Also, if the discharge pressure Pd is a normal value (for example, 14 kg/a#
) (e.g. 20 kg/aj>,
That is, when the capacity of the compressor is reduced, the ball valve body 36 receives a correspondingly higher pressure from the plunger 39, making it difficult to open the valve, and therefore the suction pressure Ps becomes lower than the normal value (for example, 2 kg/a[t]). is also low (e.g. 1.7 kg/
The valve is automatically adjusted so that it opens only when the As a result, the operation of the control member 24 in the B direction (FIG. 5) is delayed, so that the discharge capacity of the compressor increases, and so-called high pressure correction is performed.

Note that the ball valve body 36 is used as the valve body of the on-off valve mechanism 33.
A needle valve may be used instead.

(Effects of the Invention) As explained above, the present invention includes a cam ring whose both sides are closed with side blocks, a rotor rotatably disposed within the cam ring, and a rotor that is slidably fitted into a vane groove of the rotor. In the vane type compressor, the vane compressor compresses fluid by changing the volume of a cavity defined by the side block, the cam ring, the rotor, and the vane. a bypass port provided in the side block having a port; a pressure working chamber provided in the side block having the suction boat and communicating with the low pressure chamber side and the high pressure chamber side; The bypass port has a pressure receiving portion fitted in a slidable manner so as to be airtightly partitioned into a first chamber communicating with the low pressure chamber side and a second chamber communicating with the high pressure chamber side. a control member that controls the opening angle; a biasing member that biases the control member in a direction in which the opening angle of the bypass port increases; a communication path that communicates the second chamber with the low pressure chamber side; a valve body disposed in a communication passage that closes the communication passage when the low pressure chamber side pressure is above a predetermined value and opens the communication passage when the low pressure chamber side pressure is below a predetermined value; an on-off valve mechanism having a hysteresis prevention member that always urges the valve in the valve closing direction by pressure on the high pressure chamber side, and the control member rotates in accordance with the differential pressure between the first chamber and the second chamber. The invention is characterized in that by controlling the opening angle of the bypass port, the compression start timing can be controlled and the discharge capacity can be variably controlled.

Therefore, since the pressure of the compressor is used to control the control member, the structure of the variable displacement control mechanism is simple and compact, and its assembly is easy, low in cost, and highly reliable. Furthermore, since the pressure working chamber also serves as a part of the passage for releasing high pressure to the low pressure side, space can be used effectively, making variable displacement control even more effective especially for this type of compressor, which is subject to space constraints. The mechanism can be made more compact.

Furthermore, since hysteresis in the opening/closing valve mechanism is prevented, controllability is further improved, and there is also the effect that so-called high pressure correction is automatically performed when the discharge pressure becomes higher than normal.

[Brief explanation of drawings]

1 to 8 show an embodiment of the vane type compressor of the present invention, FIG. 1 is a partially cutaway side view of the vane type compressor, and FIG. 3 is a sectional view taken along the line ■-■ in FIG. 1, and FIG. 4 is a sectional view taken along the line rV-rV in FIG.
5 is a sectional view taken along line ■-■ in FIG. 1, FIG. 6 is a sectional view taken along line VI-VI in FIG. 4, and FIG.
The figure is an exploded perspective view of the main part, and FIG. 8 is an enlarged sectional view of the main part. 7... Cam ring, 8... Front side block, 9.9a... Rear side block, 10... Rotor, 13... Gap chamber, 14... Vane groove, 15□~
15. ...Vane, 16...Suction boat, 17...
・Suction chamber (low pressure side chamber), 19...Discharge chamber (high pressure side chamber)
, 23... Bypass port, 24... Control member, 2
6... Pressure receiving part, 27... Pressure operation chamber, 27□... First chamber, 27□... Second chamber, 31... Coil spring (biasing member), 32... Communication passage, 33... Opening/closing valve mechanism, 34... Bellows, 34a... Rod, 35...
...Case, 36...Ball valve body, 37...Spring,
39... Plunger (hysteresis prevention member).

Claims (1)

[Claims] 1. A cam ring with side blocks closed on both sides,
A cavity defined by the side block, the cam ring, the rotor, and the vane includes a rotor rotatably disposed within the cam ring, and a vane slidably fitted in a vane groove of the rotor. In a vane type compressor that compresses fluid by volume variation, a bypass port is provided in the side block having the suction port of the two side blocks, and a bypass port is provided in the side block having the suction port and is a low pressure compressor. a pressure working chamber communicating with the chamber side and the high pressure chamber side; a first chamber communicating within the pressure working chamber with the low pressure chamber side; and a second chamber communicating with the high pressure chamber side. a control member for controlling the opening angle of the bypass port, the control member having a pressure receiving portion slidably fitted in an airtight manner to partition the bypass port; and a control member for controlling the opening angle of the bypass port; an urging member that applies pressure; a communication path that communicates the second chamber with the low pressure chamber side; and an urging member that is disposed in the communication path and closes the communication path when the pressure on the low pressure chamber side is equal to or higher than a predetermined value. and an on-off valve mechanism having a valve body that opens the communication passage when the low pressure chamber side pressure is below a predetermined value, and a hysteresis prevention member that always urges the valve body in the valve closing direction by the high pressure chamber side pressure. The control member rotates according to the pressure difference between the first chamber and the second chamber to control the opening angle of the bypass port, thereby controlling the compression start timing and variable control of the discharge volume. A vane type compressor characterized by being able to perform