JPS6334320B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a variable capacity vane compressor used in vehicle air conditioners and the like.

Generally, when the vehicle air conditioner has a high cabin temperature and a large cooling load, the compressor is turned off at 100%.
% capacity, and as the cabin temperature drops and the cooling load becomes smaller, reducing the compressor capacity is being considered. As shown in Japanese Unexamined Patent Publication No. 55-125992, such a variable displacement vane compressor has a working chamber formed by a cylinder, a rotor, and a vane, which changes over time from the suction stroke to the compression stroke. There is a structure in which, when the compression starts, the on-off valve of the reduction hole communicating between the working chamber and the suction chamber is opened, and the compressed gas is returned to the suction chamber to be expanded again.

However, the vane compressor has a drawback in that the gas that has been compressed to a certain extent is returned to the suction chamber as it is to be re-expanded, so the power generated during re-expansion cannot be used, resulting in a large power loss.

The present invention was devised to solve the above-mentioned defects, and its purpose is to divide the suction chamber into two, a first suction chamber and a second suction chamber, and to supply gas to the first suction chamber from the outside. A main suction port is provided to supply gas to the working chamber, and a reduction hole communicates the working chamber in the middle of compression operation with the second suction chamber. By communicating with the working chamber at the beginning of the suction stroke through a sub-suction hole and re-expanding the compressed gas in the same working chamber, gas that has been compressed to some extent during small capacity operation can flow into the working chamber at the beginning of the suction stroke and be re-expanded. An object of the present invention is to provide a variable displacement vane compressor that can reduce power loss and reduce the amount of suction gas sucked from the circuit by using the re-expansion energy as a force for promoting the rotational movement of the rotor. .

Hereinafter, a first embodiment embodying a variable capacity vane compressor of the present invention will be explained with reference to FIGS. 2 and 3 are joined and fixed, a front housing 4 is joined and fixed to the front end surface of the front side plate 2, and a suction chamber 5 is formed by both members. A rear housing 6 having a cylindrical shape with a bottom is fitted and fixed on the outer peripheral surfaces of the cylinder 1 and both side plates 2 and 3.
The front housing 4 and the front housing 4 are mutually tightened and fixed by a plurality of bolts 7 shown in FIG. or,
The cylinder 1, the rear side plate 3, and the front and rear housings 4, 6 are each tightened and fixed with a plurality of bolts (not shown).

The side plates 2, 3 and the front housing 4 are integrally formed with shaft supporting cylinder portions 2a, 3a, and 4a eccentrically from the central axis of the cylinder 1. A rotary shaft 9 is supported by the shaft support cylinder portions 2a, 3a via a radial needle bearing 8, and a shaft seal mechanism 10 is interposed between the shaft 9 and the shaft support cylinder portion 4a. A horizontal cylindrical rotor 11 located inside the cylinder 1 is integrally formed in the middle part of the rotating shaft 9, and both front and rear end surfaces of the rotor 11 are in sliding contact with the end surfaces of the pair of side plates 2 and 3, and the outer circumferential surface As shown in FIG. 2, the cylinder 1 is locally slidably contacted with the inner circumferential surface of the cylinder 1.
Further, a plurality of vane grooves 11a are formed on the outer peripheral surface of the rotor 11 over the entire width of the rotor, and a vane 12 is fitted into each vane groove 11a so as to be retractable.

On the other hand, as shown in FIG. 3, a partition wall 13 is integrally formed on the inner wall surface of the front housing 4 to divide the suction chamber 5 into a first suction chamber 5a and a second suction chamber 5b. The shaft seal mechanism 10 is located at. The first suction chamber 5a is connected to the outer periphery of the front housing 4 from the outside.
An inlet 14 is provided for introducing gas into the tank.
The front side plate 2 is formed by the first suction chamber 5a and the working chamber in the cylinder 1, that is, the cylinder 1, the front and rear side plates 2, 3, the rotor 11, the vane 12, etc. A main suction hole 16 is provided through the main suction hole 16 which communicates with the working chamber 15 which changes over time during the compression stroke. The terminal edge e of this main suction hole 16 is connected to the two vanes 12a, front and rear, forming the working chamber 15 with the maximum suction volume.
The vane 12b is made to substantially coincide with the front surface of the succeeding vane 12b, and the starting edge s is located close to the rear surface of the succeeding vane 12b.

In addition, a reduction hole 17 is provided in the front side plate 2 to communicate the working chamber 15 in the compression stroke with the second suction chamber 5b, so that during the compression stroke from the working chamber 15 to the second suction chamber 5b during small capacity operation. gas supply. As shown in FIG. 1, a solenoid valve 18 is fitted and fixed into a mounting hole 4b extending through the front housing 4 corresponding to the reduction hole 17, and a spool 19 and a valve fixed to the tip of the spool are fitted. The plate 20 is biased by a coil spring 21 in a direction to close the reduction hole 17. Similarly, on the front side plate 2, as shown in FIG. A sub suction hole 2 communicating with the working chamber 15 of
2 is transparently installed, and gas in the middle of compression is supplied from the second suction chamber 5b to the working chamber 15 for re-expansion during small capacity operation. This auxiliary suction hole 22 is placed as close as possible to the top positions T and P.

By the way, in the present invention, the gas in the working chamber 15 during the compression operation is transferred to the working chamber 15 at the beginning of the suction stroke through the reduction hole 17, the second suction chamber 5b, and the auxiliary suction hole 22.
to the working chamber 1 at the beginning of the suction stroke.
It is necessary to increase the negative pressure generated at 5 to positive pressure. Therefore, the reduction hole 1 should be adjusted to satisfy this requirement.
7 opening position (if it is too close to the trailing vane 12b, the gas pressure will be too low and the negative pressure cannot be made into a positive pressure),
Alternatively, the sizes of the reduction hole 17 and the sub-intake hole 22 are set.

As shown in FIG.
3 and the rear housing 6 form a discharge chamber 24. The discharge chamber 24 and the working chamber 15 for the compression stroke are formed by a plurality of discharge holes 25 transparently provided in the cylinder 1.
A check valve 26 and a retainer 27 are fixed to the partition wall 23 so as to correspond to these discharge holes 25. As shown in FIG. 1, the rear side plate 3 is provided with a passage 29 that communicates the discharge chamber 24 with an oil separation chamber 28 formed at the rear of the rear housing 6.

A cap 30 is fixed to the rear end surface of the rear side plate 3 so as to cover the radial bearing 8, and an oil suction hole (not shown) is provided in the rear side plate 3 so as to communicate the cap 30 with the oil separation chamber 28. ) is provided. Further, each vane groove 11 is provided on the front surface of the side plate 3.
A groove 3b is cut in the side plate 3 to communicate with each other, and the groove 3b and the inside of the cap 30 are communicated through an oil guide hole 3c formed through the side plate 3.

Furthermore, an oil separation filter 31 is disposed between the inner peripheral surface of the rear housing 6 and the cap 30 in correspondence with the passage 29, and an oil separation chamber is provided on the outer periphery of the rear housing 6. A discharge port 32 is provided for transferring the compressed gas within the gas chamber 28 to the outside.

Next, the operation of the variable displacement vane compressor mentioned above will be explained.

First, explanation will be made regarding operation at 100% capacity. In this case, the solenoid valve 18 is in a demagnetized state due to the control action of a capacity controller (not shown), and the spool 19 and the valve plate 20 are turned on by the spring 21. In FIG. 1, it moves to the rear side and closes the reduction hole 17. When the rotor 11 is rotated in the direction of the arrow in FIG. 2 in this state, the tip of each vane 12 comes into sliding contact with the inner circumferential surface of the cylinder 1 and rotates together with the rotor 11. The working chamber 15 at the beginning of the suction stroke, which is formed between the top position T/P where the cylinder 1 and the rotor 11 are closest to each other, and the vane 12 that has passed the top position T/P, becomes negative pressure due to a gradual increase in volume, and the sub-intake I try to inhale gas from the hole 22, but the reduction hole 17
is closed and gas does not flow into the second suction chamber 5b, so that no gas is inhaled from the sub-suction hole 22.

When the rotor 11 is rotated and the vane 12 passes the starting edge s of the main suction hole 16, the gas in the first suction chamber 5a is sucked into the working chamber 15 through the main suction hole 16. The maximum volume of the working chamber 15 is the suction of this gas.
i.e. the subsequent vane 12 forming the working chamber 15
This is continued until the end edge e of the main suction hole 16 is reached.

After the succeeding vane 23 passes the end edge e of the main suction hole 16, compression of the working chamber 15 begins, and the compressed gas is sent under pressure from the discharge hole 25 to the discharge chamber 24. The gas pressure-fed to the discharge chamber 24 passes through the passage 29 to reach the oil separation chamber 28, and is discharged to the outside from the discharge port 32.

Next, when small capacity operation is required due to excess capacity, the solenoid valve 18 is controlled by the control action of the capacity controller.
is excited, the spool 19 is moved to the front side in FIG. 1, and the reduction hole 17 is opened. Then,
The compressed gas from the time when the working chamber 15 reaches its maximum volume and starts compression until the succeeding vane 12b passes through the reduction hole 17 is sent under pressure to the second suction chamber 5b through the same hole 17, and is further compressed into the second suction chamber 5b. It is supplied from the suction chamber 5b through the sub-suction hole 22 to the working chamber 15 at the beginning of the suction stroke. At this time, the gas that has entered the working chamber 15 is compressed to some extent and has a high pressure, so it expands again within the working chamber 15, overcomes the negative pressure generated by the gradual increase in the volume of the working chamber 15, and creates a positive pressure in the working chamber 15. to rise to. When this compressed gas expands, the pressure of the gas causes the preceding vane 12 of the working chamber 15 to
The rotation of the rotor 11 is promoted by the force that presses the rotor 11 in the direction of rotation of the rotor.

On the other hand, the subsequent vane 12 forming the working chamber 15
After passing through the reduction hole 17, substantial compression takes place. Therefore, in this embodiment, if the maximum volume of the working chamber 15 is V ₀ and the volume of the working chamber at the time when the succeeding vane 12 passes through the reduction hole 17 is V, then the maximum volume of the working chamber 15 is (V ₀ −V). It is possible to reduce the capacity by the volume.

Now, in the first embodiment of the present invention, the suction chamber 5 in the front housing 4 is divided into a first suction chamber 5a and a second suction chamber 5b, and the compressed gas at the beginning of the compression stroke is passed from the reduction hole 17 to the second suction chamber. 5b, and further supplied from the auxiliary suction hole 22 to the working chamber 15 at the beginning of the suction stroke to re-expand it and change the negative pressure generated in the same chamber 15 into positive pressure.
The energy can be re-expanded within the rotor and used as a force for accelerating rotor rotation, reducing power loss. In addition, since the re-expansion of the compressed gas can be converted into rotor rotational force in this way, there is no need to consider power loss even if the reduction hole 17 is located somewhat close to the discharge hole 25. The degree of freedom in the opening position of the hole 17 can be increased.

Next, a second embodiment of the present invention will be described with reference to FIG.

In this embodiment, a communication hole 33 is provided through a partition wall 13 which is integrally formed in the front housing 4 and defines first and second suction chambers 5a and 5b, and allows the two suction chambers 5a and 5b to communicate with each other. Partition wall 13
The second suction chamber 5b is characterized in that a check valve 34 capable of opening and closing the communication hole 33 is fixed to the side wall surface of the second suction chamber 5b with bolts, but the other configuration is the same as that of the first embodiment. Therefore, in this second embodiment, when operating at 100% capacity, the gas in the first suction chamber 5a moves through the communication hole 33 to the second suction chamber 5b, and further through the sub-suction hole 22 at the beginning of the suction stroke. Since the pressure is supplied to the working chamber 15 of the working chamber 15, it is possible to prevent the working chamber from becoming a negative pressure and to further reduce power loss.

In addition, when operating at 100% capacity, the second suction chamber 5b
Since the cold gas is inhaled into the second suction chamber 5b, the shaft seal mechanism 10 may be located in the second suction chamber 5b. Therefore, the shape of the partition wall 13 may be changed so as to enclose the seal mechanism 10 as in the first embodiment. The shape of the partition wall 13 can be simplified accordingly.

Further, in the third embodiment shown in FIGS. 5 to 8, the first suction chamber 5a' is disposed within the rear housing 6a, and the second suction chamber 5b' is disposed within the front housing 4. There are certain characteristics,
Since the other configurations and their functions are almost the same as those of the first embodiment, detailed explanations will be omitted. Furthermore, in the fourth embodiment shown in FIGS. 9 to 11, the first suction chamber is omitted and the suction refrigerant is supplied to the working chamber 15 through the suction port 14'' provided in the cylinder 1.
The main feature is that the second suction chamber 5b'' is provided in the front housing 4, and the other configurations and functions are almost the same as in the first embodiment, so a detailed explanation will be omitted. is omitted.

Further, the present invention can also be embodied in the following embodiments.

(1) In the embodiment described above, the main suction hole 16 was provided locally, but this starting edge s should be extended toward the sub-suction hole 22 side. In this way, also in the first embodiment, it is possible to reduce the negative pressure generated in the working chamber 15 at the beginning of the suction stroke during operation at 100% capacity.
However, in this case, during small capacity operation, the compressed gas that is pressurized into the working chamber 15 at the beginning of the suction stroke tends to escape from the main suction hole 16 to the first suction chamber 5a, so if it is brought too close, it will cause a problem. be.

(2) The shape of the reduction hole 17 is formed to be the same as or smaller than the cross-sectional shape of the vane 12 protruding from the rotor 11. In this way, 100
When the vane 12 passes through the reduction hole 17 during operation at % capacity, it is possible to prevent the gas being compressed from leaking into the working chamber during the suction stroke.

(3) Instead of directly opening and closing the reducing hole 17 using a solenoid valve built into the compressor, a spool is provided that opens and closes the reducing hole 17 by alternating discharge pressure and suction pressure, and the spool A solenoid valve shall be installed outside the compressor to appropriately switch the pilot pressure of the discharge pressure and suction pressure supplied to the compressor.

As detailed above, the present invention allows gas that has been compressed to some extent during small capacity operation to flow into the working chamber at the beginning of the suction stroke and re-expands it, and then uses the re-expansion energy as a force to promote the rotational movement of the rotor. , power loss can be reduced, and 100
Even when operating at % capacity, there is an effect of eliminating negative pressure in the initial state of suction and eliminating power loss.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the variable capacity vane compressor of the present invention, and FIG.
A line sectional view, Figure 3 is a - line sectional view of Figure 1,
FIG. 4 is a cross-sectional view of a front housing showing a second embodiment of the present invention, and FIG. 5 is a vertical cross-sectional view (-cross-sectional view in FIG. 6) showing a third embodiment.
6 is a sectional view of FIG. 5, FIG. 7 is a sectional view of FIG. 5, FIG. 8 is a sectional view of FIG. 5, and FIG. 9 shows a fourth embodiment. A vertical sectional view, FIG. 10 is a - sectional view in FIG. 9, and FIG. 11 is a cross-sectional view taken from XI-XI in FIG. 9.
FIG. Cylinder...1, Front and rear side plates...2, 3, Front housing...4,
First and second suction chambers...5a, 5b, rotating shaft...
...9, Rotor...11, Vane...12, Bulkhead...
...13, Working chamber...15, Main suction hole...16, Reduction hole...17, Solenoid valve...18, Sub-suction hole...2
2. Communication hole...33, Check valve...34.

Claims (1)

[Claims] 1. A rotor having vanes is rotatably installed inside the cylinder, and front and rear side plates are fixedly connected to both front and rear end surfaces of the cylinder, and a first suction chamber and a second suction chamber are provided. The first suction chamber has a suction port for sucking gas from the outside, and the working chamber formed by the cylinder, both side plates, rotor, vanes, etc. receives gas from the first suction chamber. A main suction port is opened for inhaling the compressed gas, a discharge hole having a check valve is opened for discharging the compressed gas to the outside, and the gas being compressed is guided to the second suction chamber. A reduction hole is provided in the working chamber at the beginning of the pre-air intake stroke, and a sub-intake port is opened in the working chamber at the beginning of the pre-air intake stroke to suck in the compressed gas from the second suction chamber and re-expand it in the working chamber. A variable capacity vane compressor characterized in that the hole is provided with an on-off valve that opens and closes depending on the load state. 2. The variable displacement vane compressor according to claim 1, wherein the terminal edge of the main suction hole is located approximately at the same position as the leading edge of the succeeding vane forming the working chamber with maximum suction volume. 3. The variable displacement vane compressor according to claim 1, wherein the auxiliary suction hole is opened in the working chamber at the very beginning of the suction stroke near the top position where the rotor is closest to the cylinder. 4. The variable displacement vane compressor according to claim 1, wherein the starting edge of the main suction hole is located close to a subsequent vane forming a working chamber of maximum suction volume. 5 A rotor with vanes is rotatably installed inside the cylinder, and front and rear side plates are fixedly connected to both the front and rear end surfaces of the cylinder to define a first suction chamber and a second suction chamber. A communication hole communicating the first and second suction chambers is provided in the partition wall separating the two, and a check valve is provided in the communication hole to prevent gas from flowing back from the second suction chamber to the first suction chamber. A suction port for sucking gas from the outside is opened in the first suction chamber, and a working chamber formed by the cylinder, both side plates, a rotor, a vane, etc. sucks gas from the first suction chamber. a discharge hole having a check valve for discharging the compressed gas to the outside, and a reduction hole for guiding the gas during the compression operation to the second suction chamber. A sub-suction hole is opened in the working chamber at the beginning of the suction stroke for sucking the gas in the middle of compression from the second suction chamber and re-expanding it in the working chamber, and the reduction hole is opened in the working chamber in a loaded state. A variable capacity vane compressor characterized by being equipped with an on-off valve that opens and closes depending on the conditions.