JPS62248890A - Vane type compressor - Google Patents

Abstract

PURPOSE:To improve the compressing operation by providing a reed valve in a back pressure hole coupling between a back pressure groove made in the bottom of a vane groove and a delivery chamber then separating the reed valve and a valve seat by predetermined height. CONSTITUTION:A back pressure groove 231 is formed in a rear end plate 114 at a rotor 121 side and communicated through a back pressure hole 233 with a delivery chamber 143. A back pressure reed valve 234 is held between the rear and plate 114 and a housing 111 so as to perform opening/closing of the back pressure hole 233 and a back pressure valve seat 235 is separated by predetermined height from the back pressure reed valve 234. Consequently, the opening/closing of the back pressure groove is controlled well by means of the back pressure reed valve thereby the compressing operation of compressor can be performed well from the start.

Description

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

[Conventional technology]

It has been known to use a vane compressor as a refrigerant compressor for automobile air conditioners.

For example, a vane type compressor is also shown in Japanese Utility Model Publication No. 58756392.

This type of vane compressor is provided with a passage connecting the bottom of the vane and the discharge chamber to facilitate the ejection of the vane. During start-up, external pressure is supplied to the bottom of the vane through this passage, so that the vane can be better ejected from the vane groove.

However, if the passage connecting the discharge chamber and the bottom of the vane were always open, fluid at a higher pressure than the discharge chamber would always be applied to the bottom of the vane, which is undesirable. Therefore, a check valve is usually provided in this passage.

However, the passage connecting the bottom of the vane and the discharge chamber is usually a fine passage, and it is extremely difficult to assemble a check valve there. At the same time, the overall shape of the check valve becomes small, which not only makes assembly difficult, but also poses a problem in the durability of the check valve.

[Problem that the invention seeks to solve]

The present invention was devised in view of the above-mentioned points, and an object of the present invention is to enable a vane to properly pop out of a vane groove during startup and the like. Furthermore, it is an object of the present invention to provide a check valve that is necessary for improving vane protrusion with an extremely simple structure. That is, an object of the present invention is to enable the check valve to be installed without impairing the assembly properties. A further object of the present invention is to provide sufficient durability to the attached check valve.

[Configuration and operation]

In order to achieve the above object, in the present invention, an end plate is disposed on the side surface of a cylinder housing having a cylinder chamber, and the end plate is disposed together with the end plate to form a discharge chamber at a position opposite to the cylinder chamber.

Further, a back pressure groove facing the vane groove is formed on the rotor side surface of the end plate. This back pressure groove is formed to face the vane groove at least at the protrusion stroke position of the vane. Further, a back pressure hole is formed in the end plate to connect the back pressure groove and the above-mentioned discharge chamber. Further, a back pressure valve made of a reed valve is formed on the discharge chamber side of the end plate.

Also, the valve seat of the reed valve is formed on the end plate.
However, in the normal position of the back pressure reed valve, the back pressure reed valve is configured not to come into contact with the valve seat.

Next, the operation of the compressor having the above configuration will be explained.

When the compressor is started, high pressure is not yet generated in the discharge chamber. Therefore, the pressures in the discharge chamber and the bottom of the vane are approximately the same. Therefore, the back pressure reed valve is not in contact with the back pressure valve seat, and the discharge chamber and the bottom of the vane are communicated through the back pressure hole and the back pressure groove. Therefore, the fluid in the discharge chamber is supplied to the bottom of the vane through the back pressure hole and the back pressure groove.

As a result, no sealed space is created at the bottom of the vane during startup, and there is no pressure drop at the bottom of the vane, so that the vane can smoothly pop out of the vane groove. The vanes therefore begin to compress well.

After the compressor starts compression, fluid is discharged into the discharge chamber at high pressure. As a result, the pressure inside the discharge chamber increases.

When a pressure difference greater than a predetermined value is generated between the discharge chamber and the back pressure groove due to an increase in the pressure inside the discharge chamber, the back pressure reed valve comes into contact with the back pressure valve seat.

This blocks the back pressure hole and prevents the high pressure fluid in the discharge chamber from being excessively supplied to the bottom of the vane.

〔Effect of the invention〕

In the compressor of the present invention, the opening and closing of the back pressure groove is well controlled by the back pressure reed valve as described above. Therefore, at the time of startup, the fluid in the discharge chamber is well supplied to the bottom of the vane, and the compressor can perform a good compression operation from the time of startup.

Further, in the compressor of the present invention, a back pressure reed valve is used as a check valve for the back pressure hole, and since this back pressure reed valve is arranged at the end of the end plate, the installation work is extremely easy.

Further, in the present invention, the back pressure hole need only be formed in the end plate, and the back pressure hole need only be formed so as to pass through the end plate, so that the work of forming the back pressure hole is extremely easy.

〔Example〕

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

In FIG. 1, reference numeral 111 denotes a housing having a cylindrical shape with a bottom, and inside this housing 111 is a cylinder housing 115.
is accommodated. The cylinder housing 115 forms a compression chamber 225 inside. A front end plate 113 is disposed at one end of the cylinder housing 115, and a rear end plate 114 is disposed at the other end of the cylinder housing 115. Both ends of the cylinder housing 115 are closed by the front end plate 113 and the rear end plate 114.

A rear end plate 114, a cylinder housing 115, and a front end plate 113 are disposed inside the housing 111, and in this state, the front housing 13
3 is arranged to close the housing 111. A seal is maintained between the housing 111 and the front housing 133 by an O-ring 141. In this assembled state, the through bolts 135 are used to tighten and fix the parts together.

The rear end plate 114 has a bearing section 124 in its center.
is formed. Also front end plate 113
A bearing 125 is also arranged in the center of the. The shaft 123 has an end rotatably supported by the above-mentioned bearing portion 124, and a central portion rotatably supported by the above-described bearing 125. Therefore, the shaft 123 is rotatably supported within the cylinder housing 115.

The rotor 121 rotates integrally with the shaft 123.

That is, the rotor 121 rotates within the compression chamber 225 as the shaft 123 rotates.

A shaft seal 131 is disposed between the shaft 123 and the front housing 133.

This shaft seal 131 prevents the refrigerant in the suction chamber 134 from leaking to the outside along the shaft 123.

Although not shown, an electromagnetic clutch is disposed outside the front housing 133, and the rotational driving force of an automobile engine or the like is transmitted to the shaft 123 via this electromagnetic clutch.

A plurality of vane grooves 243 are formed in the rotor 121, and a vane 155 is slidably disposed in each vane groove 243. Further, a vane bottom space 244 is formed at the bottom of the vane groove 243 .

Back pressure grooves 231 are formed at two locations on the surface of the rear end plate 114 on the rotor 121 side.

As shown in FIG. 4, the high pressure relief groove 153 is formed at a portion facing the vane space 244 when the vane 155 is in the compression process. Further, the back pressure groove 231 is formed at a position facing the vane space 244 when the vane 155 is in the protruding stroke.

A back pressure hole 233 is also formed in the rear end plate 114. The back pressure hole 233 is located in the rear end plate 114.
It is formed to penetrate through the That is, the first
As shown in the figure, the back pressure hole 233 is connected to the back pressure groove 231 and the discharge chamber 1.
43 is formed so as to communicate with each other.

A valve plate 245 is disposed on the side of the discharge chamber 143 of the rear end plate 114 .

This valve plate 245 is formed of a high-tensile steel plate having a predetermined elastic force and sufficient durability.

As shown in FIG. 3, a holding portion 251 is formed. Two locations are formed to protrude radially inward from the engaging portion 251. Two back pressure reed valves 234 are integrally formed by this protruding portion.

As shown in FIG. 3, the valve plate 245 is simultaneously positioned and fixed by the through bolt 135. Therefore, no special bolts are required for fixing the valve plate 245. Further, since the valve plate 245 is fixed by a plurality of through bolts 135, its positioning is performed reliably.

Moreover, since the outer circumferential portion of the valve plate 245 is held between the rear end plate 1-114 and the housing 111, it can be held down extremely reliably. Further, the back pressure reed valve 234 is held between the rear end plate 114 and the housing 111 at its outer circumference, and the back pressure hole 233 is opened and closed at its front end. Therefore, the distance from the co-attached portion to the portion facing the back pressure hole 233 can be sufficiently long.

Therefore, the back pressure reed valve 234 can have a sufficient lift amount from the back pressure valve seat 235 without undergoing large elastic deformation. Therefore, the back pressure reed valve 234 does not require large elastic deformation and can maintain its durability for a long period of time.

The back pressure valve seat 235 is cut or ground into a tapered shape as shown in FIG. Therefore, the back pressure reed valve 234
is in the normal position (the state shown in Figure 1), the back pressure reed valve 234
A predetermined gap is formed between the back pressure valve seat 235 and the back pressure valve seat 235. That is, the back pressure reed valve 234 is a normally open valve. In other words, when the differential pressure between the discharge chamber 143 and the back pressure groove 231 is small, the back pressure reed valve 234 opens the back pressure hole 233.

The operation of the compressor having the above configuration will be explained.

When the driving force of the automobile engine is transmitted through an electromagnetic clutch (not shown), the rotor 121 is moved into the compression chamber 225.
It will rotate inside.

Here, the compression chamber 225 has an elliptical shape as shown in FIG. 4, and its central axis coincides with the shaft 123.

As a result, the inner surface of the cylinder housing 115 and the rotor 121
A crescent-shaped space is formed between the outer surface and the compression chamber 225.

Therefore, as the rotor 121 rotates, the vane 155 protrudes from the vane groove 243 up to a predetermined angle. In the example shown in FIG. 4, since the vane grooves 243 are formed in four locations, the vane 1
55 protrudes from the vane groove 243. Then rotor 12
When the rotation angle of 1 is between 90 degrees and 180 degrees, the vane 155 is pushed into the vane groove 243.

The state in which the vane 155 pops out is the protrusion stroke. In this protrusion stroke, the space in the compression chamber 225 sandwiched between the two protruding vanes expands as the rotor 121 rotates, and the refrigerant in the suction chamber 134 is sucked into the compression chamber 225 through the suction port 211. . Note that the suction port 211 is formed within the cylinder housing 155 and communicates with the suction chamber 134 via a suction passage 254.

The refrigerant sucked into the compression chamber 225 through the suction port 211 is then compressed as the volume of the compression chamber 225 decreases. The refrigerant in the compression chamber 225 is discharged from the discharge port 213 into the discharge chamber 223 in a state where the refrigerant is compressed to a predetermined value or more. Note that the discharge chamber 2
23 is formed between the cylinder housing 115 and the housing 111.

A discharge valve 21 is provided on the discharge chamber 223 side of this housing 111.
4 is arranged so that the discharge port 213 can be opened and closed.

The discharge valve 214 is supported by a valve holder 215,
The valve holder 215 and the discharge valve 214 are both fixed to the cylinder housing 115 with bolts 221.

Therefore, the high-temperature, high-pressure refrigerant compressed from the compression chamber 225 is discharged into the discharge chamber 223.

The high-pressure refrigerant in the discharge chamber 223 is then transferred to a discharge passage 224 (shown in FIG. 5) formed in the cylinder housing 115.
It flows into the discharge chamber 143 through the.

Therefore, the refrigerant discharged into the two discharge chambers 223 is collected in the discharge chamber 143. The high-pressure refrigerant collected in the discharge chamber 143 is then discharged from the discharge communication passage 255 to the condenser side (not shown) of the refrigeration cycle.

In the refrigeration cycle, lubricating oil is mixed into the refrigerant and circulated through the cycle. Therefore, the lubricating oil contained in this refrigerant lubricates the sliding parts of the compressor.
. From the discharge chamber 223 to the discharge chamber 14 via the discharge passage 224
The refrigerant discharged into the discharge chamber 143 separates the lubricating oil in the refrigerant. That is, since the volume of the discharge chamber 143 is sufficiently larger than that of the discharge passage 224, lubricating oil is separated from the refrigerant due to this volume change. Therefore, the discharge chamber 1
Lubricating oil separated from the refrigerant is stored in an oil storage space 144 formed at the bottom of the refrigerant.

As shown in FIG. 1, an oil supply passage 145 is formed within the rear end plate 114. This oil supply passage 145
The lubricating oil in the oil storage space 144 is supplied to the bearing portion 124 through the lubricating oil in the oil storage space 144. The refrigerant thus supplied is applied to the bearing part 12.
Lubrication with the shaft 123 is maintained at the four parts. Further, the lubricating oil supplied from the oil supply passage 145 then lubricates the space between the rotor 121 and the housing 111.

The operation of the compressor has been described above, and next, the operation of the back pressure hole 233 portion according to this example will be explained. This back pressure hole 233
is opened and closed by the back pressure reed valve 234 as described above, and the back pressure reed valve 234 normally opens the back pressure hole 233.

Therefore, when high pressure is not yet generated in the discharge chamber 143, such as when starting up the compressor, the back pressure reed valve 234 is connected to the back pressure hole 2.
33 is open.

Therefore, at startup, the back pressure groove 231 communicates with the discharge chamber 143 via the back pressure hole 233. Therefore vane 155
During the ejection stroke in which the vane part space 244 is about to pop out, the vane space 244 always communicates with the discharge chamber 143.

If the back pressure hole 233 is closed here, the base
- The vane space 244 becomes a sealed space, so when the vane 155 is about to pop out, the vane space 244 becomes a closed space.
The pressure inside 4 becomes a large negative pressure.

If the vane space 244 becomes negative pressure in this way, the vane 155 will be prevented from popping out. If the vane 155 does not pop out properly, the compressor will not operate satisfactorily. Particularly during startup, liquefied refrigerant and lubricating oil often remain in the vane space 244. Since such liquefied refrigerant and lubricating oil are incompressible fluids, movement of the vanes 155 is significantly inhibited.

However, in the compressor of this example, the vane space 244 is open to the back pressure hole 233 over almost the entire length of the discharge stroke. The back pressure groove 231 communicates with the discharge chamber 143 via the back pressure hole 233.

Therefore, the vane portion space 244 is not closed, and the vane 155 can be properly projected.

In the above example, four vanes 155 are provided, but the compressor of the present invention does not limit the number of vanes 155. For example, as shown in FIG. 7, the number of vanes 155 may be seven.

In the above example, the ends of the back pressure reed valves 234 are sandwiched between the rear end plate 114 and the housing 111, but the back pressure reed valves 234 may be attached to the rear end plate 114 independently.

Further, in the above example, the valve seat 235 is formed in a tapered shape on the rear end plate, but as shown in FIG. 2, the rear end plate may be formed in a flat shape, and the back pressure reed valve may be deformed by a predetermined amount.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing one embodiment of the compressor of the present invention.
FIG. 2, which shows a cross-sectional shape taken along line 1-1 in the figure, is a cross-sectional view showing an embodiment of the compressor of the present invention, and FIG.
3 is a cross-sectional view along the line mm in FIG. 1, FIG. 4 is a cross-sectional view along rV-IV in FIG. 1, and FIG.
The figure is a front view taken along arrows ``--'''' in FIG. 1, and FIG. 6 is a sectional view showing another example of the compressor of the present invention. 111... Housing, 114... Rear end plate, 115... Cylinder housing, 121...
Rotor, 123... Shaft, 153... High pressure relief groove. 154... High pressure relief hole, 155... Vane, 231
...Back pressure groove, 233...Back pressure hole, 223...Discharge chamber, 234...Back pressure reed valve, 235...Back pressure valve seat, 241...High pressure reed valve.

Claims (1)

[Claims] A cylinder housing having a cylindrical space inside, a rotor rotatably disposed within the cylinder housing, and a rotor disposed slidably within a vane groove formed in the rotor. a vane; an end plate disposed at an end of the cylinder housing; a discharge chamber formed on a side opposite to the rotor through the end plate; a back pressure groove formed in a portion where the groove bottom and the vane communicate at least during the ejection stroke; a back pressure hole formed through the end plate and connecting the back pressure groove and the discharge chamber; A reed valve is provided on the discharge chamber side and opens and closes the back pressure hole, the valve seat of the reed valve is located on the end plate, and the reed valve and the valve seat are separated by a predetermined height. Features a vane type compressor.