JPS6321386A - Variable capacity type rotary compressor - Google Patents

Abstract

PURPOSE:To favorably control the discharge capacity of a compression chamber without using a complicated structure by simultaneously controlling the discharge capacity of a plurality of compression chambers by one spool valve. CONSTITUTION:A cylinder part 237 is formed onto a front side plate 101, and a spool valve 203 is arranged in slidable ways into the cylinder part 237. A pressure chamber 201 is formed on one edge side part of the spool valve 203, and bypass ports 213 and 214 are opened on the other edge side, an the suction pressure in a suction chamber 113 is introduced. Therefore, the control of the variable opening area of a suction inlet 112 and the opening/closing control for the bypass ports 213 and 214 can be carried out by one spool valve 203, and the capacity control of a compression chamber can be carried out favourably without using a complicate structure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a rotary compressor, and is effective for use as a refrigerant compressor in, for example, an automobile air conditioner.

[Prior art and its problems]

Conventionally, rotary compression has a compression chamber formed by a cylinder with an elliptical space inside, a rotor rotatably disposed within the cylinder, and vanes slidably disposed on the rotor. The machine is known (for example, Japanese Patent Application Laid-Open No. 57-157982, Japanese Patent Application Laid-Open No. 60-192297).
Publication No.).

It has also been proposed in the past to provide this type of compressor with variable capacity means. As a variable capacity means, for example, a so-called suction gas throttling method is known, which restricts the opening area of the suction port. As shown in Figure 8, this consists of a suction chamber and
The suction port 12 communicating with the compression chamber is controlled according to the displacement of the spool valve 21.

However, as is clear from FIG. 8, in this type of compressor, a plurality of compression chambers 10 are formed, so there are also a plurality of suction ports 12.

Therefore, a plurality of spool valves 21 are required to perform the throttling operation at each suction port.

Another method of variable capacitance means is to provide a bypass port as shown in FIG. 9, for example.

The bypass port 13 communicates a portion of the compression chamber 10 that is in the middle of compression with the suction chamber, and returns the compressed refrigerant to the suction chamber side. By controlling the opening of this bypass port 13 with a spool valve 21, the discharge capacity of the compression chamber can be varied.

However, due to the same problem as described above, this type of compressor requires a plurality of spool valves 21 in order to control opening and closing of the bypass port 13.

In particular, in this type of compressor, a plurality of compression chambers are connected to one shaft.
Since the suction port 12 and the bypass port 13 are formed at positions that are point symmetrical with respect to each other, the suction port 12 and the bypass port 13 must also be formed at positions that are point symmetrical with respect to each other. Therefore, each suction port 12 and bypass port 13
One spool valve 21
Therefore, it is impossible to variably control both at the same time.

[Problem to be solved by the invention]

The present invention was devised in view of the above points, and an object of the present invention is to enable variable control of the capacities of a plurality of compression chambers using one spool valve.

[Configuration and operation]

In order to achieve the above object, in the present invention, one of the plurality of compression chambers performs capacity control by variably controlling the opening area of the suction port, and the other compression chamber has a bypass port. A configuration is adopted in which capacity is controlled by controlling the opening and closing of. With such a configuration, the positions of the bypass port and the suction port to be controlled are not point-symmetrical with respect to the shaft. The present invention has been devised with this point in mind, and is designed to simultaneously perform both the throttle control of the suction port and the opening/closing control of the bypass port using a single spool valve.

That is, in accordance with the displacement of one spool valve, the opening area of the suction port is varied in the negative compression chamber, and as the suction port opening area decreases, the flow rate of refrigerant sucked into the compression chamber decreases. As a result, the discharge capacity at one compression chamber side decreases. At the same time, the bypass port opens on the other side of the compression chamber. In this way, when the bypass port is opened, the once compressed refrigerant gas is allowed to escape to the suction chamber side via the bypass port, and as a result, the discharge capacity also decreases in the other compression chamber side. .

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

Reference numeral 107 in FIG. 1 is a cylinder made of cast iron or aluminum alloy, and an elliptical space is formed inside this cylinder as shown in FIG. A rotor 108 also made of cast iron or aluminum alloy is rotatably disposed within this space. The rotor is connected to the shaft 118 at its center, and the shaft 118
It rotates together with the Further, vane grooves 130 are formed at four locations in the rotor 108 at equal intervals in the circumferential direction, and each vane groove 130 has a vane 109.
are slidably arranged. Side plates 101 and 117 are arranged on both sides of cylinder 107. The shaft 118 described above is rotatably supported at its rear end by the rear side plate 117. Further, the shaft 118 is also rotatably disposed by a hair ring 120 disposed on the front side plate 101.

A front housing 111 is disposed on the front side plate 101 at a portion opposite to the cylinder 107 . A suction service valve (not shown) is formed in the front housing so that low-temperature, low-pressure refrigerant from the evaporator side of the refrigeration cycle is sucked into the suction chamber 113 in the front housing 111.

In addition, the front housing 111 includes a shaft seal 1.
19 is provided, and this shaft seal 119 prevents the refrigerant and lubricating oil from flowing out along the shaft 118. Furthermore, a hub portion 131 is formed in the center of the front housing 111.
An electromagnetic clutch (not shown) is disposed in this hub portion. The rotational force for driving the vehicle is transmitted to the shaft 118 via an electromagnetic clutch (not shown).

A cover 110 is disposed outside the rear side plate 117, and the cover 110 and the rear side plate 1-
An oil separation chamber 114 is formed between the oil separation chamber 117 and the oil separation chamber 117 . This oil separation chamber 114 introduces the refrigerant discharged from the discharge chamber 115 and separates lubricating oil from the refrigerant. The separated lubricating oil is transferred to this oil separation chamber 1.
14, and is supplied to the sliding and rotating parts of the compressor.

The discharge chamber 115 is formed on the side of the cover 110 and communicates with the compression chamber 100 formed inside the cylinder 107 via a discharge port. A discharge valve (not shown) is disposed at a portion of the discharge chamber 115 of the discharge port.

A discharge passage 145 communicates between the discharge chamber 115 and the oil separation chamber 114 . A discharge service valve (not shown) is formed in the cover, and the high temperature and high pressure refrigerant in the oil separation chamber 114 is discharged to the condenser side (not shown) of the refrigeration cycle through this discharge service valve.

The above-mentioned cover 110, rear housing 117, cylinder 107, front side plate 101, and front housing 111 are simply connected integrally by through bolts 116. Note that the through bolts 116 are arranged at six locations as shown in FIG.

As shown in FIG. 2, a suction port 112 is formed in the front side plate 101. As shown in FIG. This intake port 112
One end opens into the suction chamber in the front housing 111, and the other end communicates with the suction start portion of the compression chamber 100. Therefore, the refrigerant in the suction chamber 113 is sucked into the compression chamber 100 through the suction port 112.

Further, a plurality of bypass ports 213 and 214 are opened in the front side plate 101. This bypass port 213, 214 has one end connected to the suction chamber 11.
3, and the other end opens to the compression process portion of the compression chamber 100. In this example, the compression chamber 100 is formed in two places, and the bypass ports 213, 2
14 opens only to the compression chamber 100 on one side.

One compression chamber 10 is provided in the front side plate 101.
A spool valve 203 is disposed on an axis connecting the suction port 112 of the compression chamber 100 and the bypass port of the compression chamber 100 of the other compression chamber. That is, the front side plate 101 has
A cylinder portion 237 is formed to slidably house the spool valve, and the spool valve 2 is provided inside the cylinder portion 237.
03 is slidably disposed.

A pressure chamber 201 is formed at one end side of the spool valve 203 . On the other hand, on the other end side of the spool valve 203, bypass ports 213 and 214 are opened, and the suction pressure in the suction chamber 113 is guided.

A signal pressure higher than the suction pressure is transmitted to the pressure chamber 201 via the pressure guiding passage. The pressure passage is connected to the spool valve 2.
03, a pressure guiding groove 205 formed on the circumferential surface of the spool valve, and a pressure guiding hole 211 formed in the front side 1" plate 101, as shown in FIG. Furthermore, it consists of a pressure guiding passage 225 formed in the gas care) 114.This pressure guiding passage 204
, 205, 211, 225 is controlled by control valve 106. The control valve 106 is held within the cover 110 and mixes the high pressure compressed in the compression chamber and the low pressure in the suction chamber to form a signal pressure. Therefore, when a high signal pressure is introduced into the pressure chamber 201 via the control valve 106, the spool valve 203 is activated as shown in FIG. This results in a downward displacement.

Next, this variable capacitance means will be explained.

As the rotor 10B rotates, the compression chamber 100 repeatedly increases and decreases in volume. In a region where the volume increases, refrigerant gas is sucked through the suction port 112. And compression chamber 1
As the volume decreases, the refrigerant gas is compressed, and when it is compressed to a predetermined value or more, it is discharged from the discharge port to the discharge chamber 115 side.

When the suction port 112 is throttled, the flow rate of refrigerant gas supplied to the compression chamber 100 will decrease.

As the intake refrigerant gas decreases, the flow rate of the discharge refrigerant gas discharged from the compression chamber also decreases.

In the state shown in FIG. 5, the spool valve 203
It is in a state where it is not actually narrowed down.

Therefore, the refrigerant gas is transferred from the suction chamber 113 to the suction port 112.
is sucked into the compression chamber 100 without encountering any flow resistance. In this state, as shown in FIG. 5, the spool 203 is displaced most downward in the figure. That is, the signal pressure supplied into the pressure chamber 201 is in a high state. Next, when the signal pressure supplied to the pressure chamber 201 decreases, the differential pressure between the pressure chamber 201 and the suction pressure chamber 229 decreases as the signal pressure decreases. As a result, the spool valve 203 is displaced upward by the force of the spring 208.

As a result, the suction port 112 is throttled by the spool valve 203 as shown in FIG. When the suction port 112 is constricted in this way, refrigerant gas cannot flow into the compression chamber 100 properly. As a result, the compression chamber 100
The flow weight of the refrigerant sucked into the tank decreases.

If the signal pressure supplied to the pressure chamber 201 further decreases, the differential pressure between the pressure chamber 201 and the suction pressure chamber 229 will further decrease, and the biasing force of the spring 208 will overcome this differential pressure. As a result, the spool valve 203 is also displaced upward by the amount shown in the figure, resulting in the state shown in FIG. In this state, the suction port 112 is completely closed and no refrigerant gas is drawn into the compression chamber 100. Therefore, the compression chamber 100 rotates without receiving refrigerant, and the discharge flow rate becomes substantially O.

As is clear from FIG. 5.6.7, this displacement of the spool valve 203 simultaneously controls the opening and closing of the bypass ports 213 and 214. In the state shown in FIG. 5, the spool valve 203 is displaced most downwardly, so both bypass ports 213 and 214 are closed.

Therefore, in the state shown in FIG. 5, the refrigerant supplied from the suction port 112 to the compression chamber 100 is compressed in its entirety and then discharged to the discharge chamber. That is, in this state, the compression chamber 100 performs compression at 100% capacity.

When the spool valve 203 is displaced upward as in the state shown in FIG. 6, one of the bypass ports 214 is opened. In this manner, when the bypass port 214 is opened, the refrigerant compressed in the one end pressure tank chamber is returned to the suction chamber 113 side via the bypass port 214.

In other words, the compression chamber 100 will not be substantially compressed unless the vane 109 passes through the bypass port 214. Therefore, the volume of the compression chamber 100 also becomes the volume after passing through the bypass port 214, and the volume decreases.

As shown in FIG. 7, when the spool valve 203 is displaced most upwardly, both bypass ports 213 and
This means that it is open. Therefore, in this state,
Until it passes through bypass port 213 on the rear side in the rotational direction,
The refrigerant will not be compressed. As a result, the discharge capacity of the compression chamber 100 is significantly reduced.

As is clear from the above explanation, as the spool valve 203 is displaced, the suction port 112 on one side of the compression chamber 100 is throttled, and as a result, the discharge capacity of the compression chamber 100 is reduced according to the displacement of the spool valve 203. Decrease. At the same time, in the compression chamber 100 on the other side, according to the displacement of the spool valve 203,
The bypass port is opened and closed, and as the bypass port opens and closes, the discharge capacity from the compression chamber on the other side also decreases. Therefore, even with - number of spool valves 203, the discharge volumes of both compression chambers 100 can be controlled simultaneously.

However, the control of the spool valves 203 does not necessarily have to be performed simultaneously. For example, the suction throttle may be first performed, and then the opening/closing control of the bypass port may be performed.

〔Effect of the invention〕

As explained above, in the compressor of the present invention, the discharge volumes of a plurality of compression chambers can be controlled simultaneously by one spool valve. Therefore, according to the present invention, it is possible to satisfactorily control the discharge volume of the compression chamber without complicating the structure.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the compressor of the present invention, FIG. 2 is a sectional view taken along the nn arrow in FIG. 1, and FIG.
4 is a cross-sectional view taken along arrows ``--'''' in FIG. 3, and FIGS. 8 and 9 are sectional views respectively showing conventionally known variable capacity means for a compressor. 100... Compression chamber, 101... Front side plate, 107... Cylinder, 108... Rotor, 1
09...Bane, 112...Inhalation 0.113...
Inhalation chamber. 201... Pressure chamber, 203... Spool valve, 213
゜214...Bypassport.

Claims (1)

[Scope of Claims] A cylinder having an elliptical internal space, a rotor rotatably disposed within the cylinder, and a vane slidably disposed within a vane groove formed in the rotor; A compression chamber defined by the inner surface of the cylinder, the outer surface of the rotor, and the vane; a side plate disposed on the end surface of the cylinder; and a suction chamber disposed on the opposite side of the cylinder with the side plate in between. a housing formed in the side plate and communicating between the suction chamber and the suction process portion of the compression chamber; A bypass port that communicates with a compression process portion; and a spool valve that is slidably disposed within the side plate, variably controls the opening area of the suction port, and controls opening and closing of the bypass port. A variable capacity rotary compressor featuring: