JPS6232292A - Vane type compressor - Google Patents

Abstract

PURPOSE:To obtain a variable capacity type compressor of simple structure, by conducting vane back pressure into the pressure receiving chamber of a piston valve opening and closing a bypass port, and communicating the pressure receiving chamber to a suction chamber via a closing valve. CONSTITUTION:In case that gas pressure of a suction chamber 20 is below a prescribed value, a ball valve 29 opens so that pressure of a vane back pressure chamber 18 drops down toward the gas pressure of the suction chamber 20. When pressure of back pressure receiving chamber 82 communicated with the vane back pressure chamber 18 becomes below spring power of a coil spring 83, slider 81 is energized by the coil spring 83 to move down toward a rotor axis 12 so that a bypass port 21 is opened. Thereby, gas which is being compressed in a cam ring 8 is relieved from the bypass port 21 into the suction chamber 20, so that compressing capacity of a vane compressor can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a vane compressor used in vehicle air conditioners and the like.

(Prior art and its problems) As is well known, a vane type compressor includes a cam ring whose both sides are closed with side blocks, a rotor rotatably disposed within the cam ring, and a vane groove of the rotor. It is equipped with a plurality of vanes that are fitted so as to be retractable and whose tips can slide into contact with the inner circumferential surface of the cam ring, and the suction chamber is compressed through the suction port by changing the volume of the compression chamber defined by the side block, rotor, and vanes. The fluid introduced into the compression chamber is compressed.

In this type of vane compressor, the compression start position is changed by adjusting the suction amount of the compressed gas.

Various so-called variable capacity vane type compressors have been proposed, which enable the compressor capacity to be controlled by realizing a full operating state where the discharge capacity is maximum and a partial operating state where the discharge capacity is reduced. ing.

However, in the conventionally proposed variable capacity vane type compressor, the suction amount adjustment mechanism for the gas to be compressed is complicated, which causes an increase in cost.

(Object of the Invention) The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a variable capacity vane type compressor that has a simple structure and can be manufactured at low cost.

(Means for Solving the Problems) In order to achieve the above object, the vane type compressor according to the present invention includes a cam ring whose both sides are closed with side blocks, and a cam ring rotatably disposed within the cam ring. A rotor, and a plurality of vanes slidably fitted in vane grooves of the rotor, and a suction chamber is provided through a suction port by a change in volume of a compression chamber defined by the side block, rotor, and vanes. In a vane type compressor configured to compress fluid introduced into the compression chamber from a compressor, the suction chamber is formed downstream of the suction port of the one side block in which the suction port is provided, and the suction chamber and the compression chamber are connected to each other. a bypass port that communicates with the vane base, and a back pressure receiving chamber into which back pressure applied to the base of the vane is introduced. an opening/closing means that is biased in a direction to open the bypass port by force; an opening/closing valve that opens and closes a communication path that communicates the back pressure receiving chamber and the suction chamber; When the on-off valve is opened, the pressure in the back pressure receiving chamber is lowered to below the spring force, and when the pressure in the suction chamber is above the predetermined value, the on-off valve is closed to lower the back pressure. The present invention is characterized by comprising a control means for increasing the pressure in the pressure receiving chamber to a level higher than the spring force.

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

1 to 5 show a vane type compressor according to a first embodiment of the present invention. In the figure, the compressor housing l
consists of a bottomed cylindrical case 2 with one end open, and a front head 4 attached to one end of the case 2 with bolts 3 so as to close the opening.

A gas discharge port 5 as a heat medium is provided on the top surface of the case 2, and a gas suction port 6 is provided on the top surface of the front head 4.
are provided respectively.

A compressor main body 7 is housed inside the housing 1 . The compressor main body 7 includes a cam ring 8, a front side block 9 and a rear side block 10 attached to both open ends of the cam ring 8 so as to close the opening surfaces, and a compressor body 7 rotatably housed inside the cam ring 8. The main components are a rotor 11 and a rotating shaft 12 of the rotor 11, and the rotating shaft 12 is rotatably supported by bearings 13 and 14 provided on both side blocks 9 and 10.

The inner circumferential surface of the cam ring 8 has an elliptical shape as shown in FIG.

Therefore, compression chambers 15.15 are defined at 180 degrees symmetrical positions between the inner peripheral surface on the long axis side of the cam ring 8 and the outer peripheral surface of the rotor 11.

The rotor 11 is provided with a plurality (for example, four) of vane grooves 16 extending in the radial direction at equal intervals in the circumferential direction, and vanes 17 can freely move in and out of the vane grooves 16 in the radial direction. , whose tip is fitted so as to be slidably in contact with the inner circumferential surface of the cam ring 8. A back pressure chamber 18 is defined between the bottom of each vane groove 16 and the base end of the vane 17, and this back pressure chamber 18
Lubricating oil is pumped into the The back pressure accumulated in the back pressure chamber 18 is set to an appropriate value 1 that allows the vane 17 to easily pop out from the vane groove 16 and that does not cause excessive sliding resistance when the tip of the vane 15 slides against the inner peripheral surface of the cam ring 8. For example, it is well known that the pressure is set to 1/2 of the sum of the discharge pressure and the suction pressure (ie, intermediate pressure).

As shown in FIG. 3, the side block 9 has 180
Suction ports 19 and 19 are provided at symmetrical positions. The front head 4
The suction chamber 20 between the front side block 9 and the compression chamber 15 communicate with each other. Further, this side block 9 is provided with a bypass port 21.21 at a 180 degree symmetrical position on the downstream side of the suction port 19.19. These bypass ports 21.21 are connected to the suction ports 19.1.
Similarly to 9, the suction chamber 20 and the compression chamber 15 are communicated with each other.

The opening and closing of the bypass port 21.21 is controlled by a piston valve 22. Figure 1 shows a state in which the piston valve 22 closes the bypass port 21 (upper side) and a state in which it opens (
(lower side) are shown respectively. This piston valve 22 is
As shown in FIGS. 1 and 2, a movable piston portion 23 is supported by the front head 4 at the inner bottom of the suction chamber 20 so as to be slidable in the axial direction of the rotor 11, and a side block 9 side of the movable piston portion 23. It consists of port valves 25.25 protruding from both ends of an arm 24 standing upright at one end and slidingly contacting a part of the inner peripheral surface of the bypass port 21.21. The bypass port 21.21 has a small diameter hole on the compression chamber 15.15 side and a large diameter hole on the suction chamber 20 side. Port valve 25.2
5 slides into a part of the inner periphery of the large diameter hole and moves forward and backward, opening and closing the small diameter hole whose tip forms a valve seat. And port valve 25
, 25 retreats to the suction chamber 20 side and opens the small diameter hole,
The suction chamber 20 and the compression chamber 15.15 communicate through large diameter holes.

The port valve 25.25 is always connected to the suction chamber 2 by the corrugated leaf spring 26.
It is biased toward the 0 side. The corrugated plate spring 2G is formed into a ring shape, and its inner peripheral end is held between the front side block 9 and the front head 4, and its outer peripheral end is locked to the side peripheral surface of the port valve 25.25.

A back pressure receiving chamber 2 is provided at the sliding contact portion on the other end side of the piston movable portion 23.
7 is provided. This back pressure receiving chamber 27 communicates with the back pressure chamber 18 via a communication passage 28.

On the other hand, as shown in FIG. 4, the front side block 9 is provided with a ball valve 29 as an on-off valve. This ball valve 29 includes a coil spring 30 disposed in the valve chamber,
It consists of a ball 31 that is biased by a coil spring 30 to close the valve seat. The valve chamber of the ball valve 29 communicates with the back pressure chamber 18 via the communication passage 32, and the ball valve 29
The valve seat 9 communicates with the suction chamber 20 via a communication passage 33. The front head 4 is provided with the ball valve 2.
A pressure-responsive body 1, for example, a bellows 34, is provided as a control means for controlling opening and closing of the pressure-responsive body 9. The bellows 34 expands and contracts depending on the pressure value of the suction chamber 20 via the communication passage 33, and a rod protruding from its tip engages with the ball 31.

Discharge ports 35° and 35 are provided on both side peripheral walls of the cam ring 8.
are bored, and communicate with the discharge chamber 36 and the compression chamber 15 inside the case 2 via these discharge ports 35 and 35.

These discharge ports 35, 35 are provided with a discharge valve 37 and a discharge valve stop 38, respectively.

(Operation) Next, the operation of the vane compressor according to the first embodiment of the present invention configured as described above will be explained.

First, the general operation of this type of vane compressor will be explained. When the rotor 11 rotates clockwise in FIG. 5 as the rotating shaft 12 rotates in relation to the engine of the vehicle, the vanes 17 protrude radially from the vane grooves 16 due to the pressure in the back pressure chamber 18 and the centrifugal force. The distal end surface rotates while slidingly contacting the inner peripheral surface of the cam ring 8, and a heat medium is introduced into the compression chamber 15 through the suction port 6, the suction chamber 20, and the suction port 19 during the suction stroke in which the volume of the compression chamber 15 is expanded. Gas is sucked in, the gas is compressed in the compression stroke to reduce the volume of the compression chamber 15, and the compressed gas is delivered to the discharge port 35 in the discharge stroke at the end of the compression stroke.
Discharge valve 37. It is supplied to a heat exchange circuit of an air conditioner (not shown) sequentially through the discharge chamber 36 and the discharge port 5.

By repeating the above operations, a fully operating state is reached where the discharge capacity is maximized and the maximum capacity is exhibited. However, when the fully operating state continues and progresses to the extent that the room temperature becomes, for example, supercooled, the suction chamber 20 is opened at the suction port 6. The pressure of the gas introduced through falls. Furthermore, the gas pressure within the suction chamber 20 is in a low state at the beginning of the operation.

Therefore, the vane compressor according to the present invention operates as follows. That is, the gas pressure in the suction chamber 2o is set to a predetermined value (for example, 2 kg).
/cd), the bellows 34 expands and pushes the ball 31 into the valve chamber against the spring force of the coil spring 30, opening the valve seat and communicating the two-speed passages 32, 33. As a result, the back pressure chamber 18 communicates with the suction chamber 20, and the back pressure decreases toward the suction gas pressure. Then, when the pressure in the back pressure receiving chamber 27 becomes equal to or lower than the spring force of the corrugated leaf spring 26, the piston valve 22 moves backward to reduce the back pressure receiving chamber 27 by the spring force of the corrugated leaf spring 26. The port valve 25 opens the bypass port 21 (the state shown at the bottom in FIG. 1). As a result, the start timing of the compression stroke is different from the full operation time, and is delayed at the time when the vane 17 passes the bypass port 21, resulting in a partial operation state in which the discharge capacity is reduced.

Next, when the gas pressure in the suction chamber 20 increases and exceeds the predetermined value, the bellows 34 contracts and the pressing force against the ball 31 disappears, so the ball 31 is pressed against the coil spring 3.
It contacts the valve seat with a spring force of 0, cutting off communication between the communication passages 32 and 33, and as a result, the pressure in the back pressure chamber 18 increases.

When the back pressure increases and the pressure in the back pressure receiving chamber 27 exceeds the spring force of the corrugated plate spring 26, the back pressure receiving chamber 27 expands against the spring force, so the piston valve 22
is urged forward in the direction of closing. bypass port 21
When the valve is closed, the start timing of the compression stroke returns to the original timing defined by the suction port 19 (the state shown in the upper part of FIG. 1).

At the beginning of operation, the gas pressure in the suction chamber 20 is originally in a low state, so the bypass port 21 starts operating in an open state from the beginning. Therefore, the shock at the time of starting is alleviated, and starting starts smoothly.

Then, the partial operating state and the full operating state are automatically repeated alternately. During partial operation, part of the discharged gas is
As shown by the arrow in the figure, from the bypass port 21 to the suction chamber 2.
is discharged to the zero side, thus reducing the capacity of the compressor. As a result, the partial operating state and the full operating state are repeated, thereby obtaining the optimum air conditioning state.

In the vane type compressor according to the first embodiment described above, the ball valve 29 is driven to open and close by the bellows 34, but instead of the bellows 34, for example, it may be constituted by a diaphragm or other suitable pressure-responsive body. can.

Alternatively, as shown in FIG. 6, the ball valve 71 may be composed of only a ball 72, a solenoid 73 for suppressing and releasing the ball 72 may be provided, and the solenoid 73 may be controlled by a control device 74. That is, the control device 74 is at room temperature (Te
mp, ), the rotation speed (rpm) of the rotor 11, and other operating parameters (PRAM, ), and calculates the gas pressure in the suction chamber 20, and if the gas pressure is less than the predetermined value, the solenoid 73 is energized. Further, the solenoid 73 is configured to be demagnetized if the gas pressure is above the predetermined value. The solenoid 73 is composed of an electromagnet 75 and an armature 77 that is biased in a direction to press the ball 72 by a coil spring 76. When the electromagnet 75 is demagnetized, the armature 77 presses the ball 72 and the communication passage 32.33 When the electromagnet 75 is excited, the armature 77 is attracted against the spring force of the coil spring 76, and the ball 72 is separated from its valve seat.

Next, FIGS. 7 to 10 show a vane type compressor according to a second embodiment of the present invention. Note that the same components as those in the first embodiment are given the same reference numerals and their explanations will be omitted.

In this second embodiment, the bypass port 21°21
A slider 81 is provided as an opening/closing means for opening and closing.

The slider 81 is disposed on the side wall surface of the front side block 9 on the compression chamber 15 side so as to be able to move up and down.
A back pressure receiving chamber 82 communicating with the back pressure chamber 18 is formed between one end of the slider 81 and the rotor shaft 12, and the other end of the slider 81 is
As shown in FIG. 9, it is constantly pressed and biased by a coil spring 82.

In addition, as shown in FIG. 10, the front side block 9
A ball valve 29 as an on-off valve is provided in the same manner as in the first embodiment, and a bellows 34 for controlling the opening and closing of this ball valve 29 is provided in the same manner as in the first embodiment.

(Operation) The operation of the vane compressor according to the second embodiment of the present invention configured as above will be explained.

゛ If the gas pressure in the suction chamber 20 is below the predetermined value,
When the ball valve 29 is opened, the pressure in the back pressure chamber 18 decreases toward the gas pressure in the suction chamber 20. When the pressure in the back pressure receiving chamber 82 becomes lower than the spring force of the coil spring 83, the slider 81 is urged by the coil spring 83 and moves downward toward the rotor shaft 12.
Bypass port 2 as shown on the lower side in Figures 7 and 9
1 is released. As a result, the device enters a partially operating state, similar to the first embodiment.

Further, when the suction gas pressure exceeds the predetermined value, the ball valve 29 closes to increase the pressure in the back pressure chamber 18. The pressure in the back pressure receiving chamber 82 expands and pushes the slider 81 toward the coil spring 83, thereby closing the bypass port 21 as shown on the upper side in FIGS. 7 and 9. As a result, the device becomes fully operational as in the first embodiment.

Next, FIG. 11 shows a vane type compressor according to a third embodiment of the present invention.

In this third embodiment, a slider 83 similar to that in the second embodiment is used as an opening/closing means for opening and closing the bypass port 21, but as a method for controlling back pressure, a back pressure receiving chamber 82 and an intake chamber are provided in the front side block 9. A communication passage 91 that communicates with the chamber 20 and a ball valve 92 that controls opening and closing of the communication passage 91.
The ball valve 92 is driven and controlled by a solenoid 93, which is controlled by a control device 74 as illustrated in FIG.

The solenoid 93 consists of an electromagnet 94 and an armature 95. When the electromagnet 94 is demagnetized, the armature 95 is biased by a leaf spring 96 and drives the ball valve 92 to close. When the electromagnet 94 is energized, the armature 95 closes the ball valve 92. is attracted and drives the ball valve 92 to open.

As a result, the same effect as in the second embodiment can be obtained.

In each of the above embodiments, the vane back pressure is controlled, but the discharge pressure may be controlled more actively.

(Effects of the Invention) As detailed above, the vane type compressor of the present invention has a bypass port that is formed on the downstream side of the suction port of the side block in which the suction port is provided and communicates the suction chamber and the compression chamber, and a vane base. has a back pressure receiving chamber into which back pressure applied to the back pressure is introduced, and is biased in a direction to close the bypass port by the pressure of the back pressure receiving chamber, and is biased in a direction to open the bypass port by a spring force. an on-off valve that opens and closes a communication path that communicates the back pressure receiving chamber and the suction chamber; The pressure in the back pressure receiving chamber is lowered to below the spring force, and the on-off valve is closed when the pressure in the suction chamber is above the predetermined value, thereby increasing the pressure in the back pressure receiving chamber to above the spring force. Since the compressor is equipped with a control means for boosting the pressure, it is possible to realize a variable capacity vane type compressor that can switch stepwise and alternately between a full operating state and a partial operating state with a simple structure that is easy to manufacture. .

Furthermore, since the back pressure control method reduces the vane back pressure during partial operation, the sliding resistance between the vane and the cam ring is reduced. Therefore, durability is improved and power loss is reduced.

Furthermore, since the engine is in partial operation at the start of operation, the shock at startup is alleviated.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a vane type compressor according to a first embodiment of the present invention, FIG. 2 is a perspective view showing essential parts of the present invention, and FIG. 3 is taken along line A-A in FIG. 1. Section m1 diagram. Figure 4 is a cross-sectional view taken along the line C-C in Figure 3, and Figure 5 is a cross-sectional view along the line C-C in Figure 3.
6 is a partial sectional view showing another embodiment of the control means shown in FIG. 4, and FIG. 7 is a vane type according to a second embodiment of the present invention. Sectional view showing the compressor, No. 8
The figure is a cross-sectional view taken along line A-A in Figure 7, Figure 9 is a cross-sectional view taken along line B-B in Figure 7, Figure 10 is a cross-sectional view taken along line E-E in Figure 8, FIG. 11 is a sectional view showing a vane type compressor according to a third embodiment of the present invention. - 8... Cam ring, 9... Front side block, 11... Rotor, 12... Rotating shaft, 15... Compression chamber, 16... Vane groove, 17... Vane, 18...
... Back pressure chamber, 19... Suction port, 20... Suction chamber, 21... Bypass port 22... Piston valve, 2
6... Corrugated plate spring, 27°82... Back pressure receiving chamber, 29
,71,92... Ball valve, 28.32,33,91
...Communication path, 34...Bellows, 73.93...
Solenoid, 74...control device.

Claims (1)

[Claims] 1. A cam ring whose both sides are closed with side blocks;
A compression chamber defined by the side block, the rotor, and the vanes, comprising a rotor rotatably disposed within the cam ring and a plurality of vanes slidably fitted in vane grooves of the rotor. In a vane compressor configured to compress fluid introduced from a suction chamber into the compression chamber through a suction port due to a change in the volume of the suction port, the suction port is located downstream of the one side block in which the suction port is provided. A bypass port is formed on the side and communicates the suction chamber and the compression chamber, and a back pressure receiving chamber is introduced into which the back pressure applied to the vane base is introduced, and the bypass port is closed by the pressure of the back pressure receiving chamber. an opening/closing means that is biased in a direction to open the bypass port and biased in a direction to open the bypass port by a spring force; an opening/closing valve that opens and closes a communication passage that communicates the back pressure receiving chamber and the suction chamber; When the pressure in the suction chamber is below the predetermined value, the on-off valve is opened to reduce the pressure in the back pressure receiving chamber below the spring force, and when the pressure in the suction chamber is above the predetermined value, the on-off valve is opened. A vane type compressor, comprising: a control means for increasing the pressure in the back pressure receiving chamber to a level higher than the spring force by closing an on-off valve. 2. The opening/closing means is a piston valve that reciprocates in the axial direction of the rotor on the suction chamber side, and one end of which forms a valve body opens and closes the bypass port, and the back pressure receiving chamber is located at the other end of the piston valve. The vane type compression device according to claim 1, wherein the piston valve is formed at a portion slidingly in contact with the bottom surface of the suction chamber, and the spring member is disposed at the one end side of the piston valve. Machine. 3. The opening/closing means is arranged to be able to move up and down on the side surface of the one side block facing the compression chamber, and opens the bypass port when it moves downward toward the rotor, and closes the bypass port when it moves upward. Claim 1: comprising a slider, wherein the back pressure receiving chamber is formed on the lower moving end side of the slider, and the spring material is disposed on the upper moving end side of the slider. Vane type compressor as described in section. 4. The vane type compressor according to claim 1, wherein the control means comprises a pressure-responsive body that opens and closes the on-off valve in response to the pressure in the suction chamber. 5. The control means comprises a solenoid that opens and closes the on-off valve, and a control device that controls excitation and demagnetization of the solenoid in accordance with a detected pressure value in the suction chamber. The vane compressor according to item 1.