JPH07133776A - Vane rotary compressor - Google Patents

Abstract

PURPOSE:To improve compression efficiency by forming a circumferential groove surrounding an opening part on the rotor side in the space behind a wane in a vane slot on either of front or rear both side plates opposed to a rotor, and arranging a sealing member of specified size in the circumferential groove. CONSTITUTION:A rotor 4 is arranged relative to a cylinder 1 through a top clearance and a vane 8 is inserted in the wane slot 7 of the rotor 4 capably of projecting and retreating. In this case, a circumferential groove 17 surrounding an opening part on the rotor 4 side in the space behind the wane 8 in the vane slot 7 is formed on either of front or rear both side plates 2, 3 opposed to the rotor 24. A sealing member 18 is arranged in the circumferential groove 17. In the sealing member 18, the thickness Wsc before assembling is set larger than the size (Ws+Wc) which is the sum of the depth Ws of the circumferential groove 17 and the fine clearance Wc between the rotor 4 and both side plates 2,3. The thickness is set to be Wsc'=Ws+Wc by deforming it at assembling.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improving the efficiency of a compressor used in an automobile air conditioner or the like by improving the internal leak seal effect.

[0002]

2. Description of the Related Art A vane rotary compressor used in a conventional automobile air-conditioning compressor is disclosed in Japanese Examined Patent Publication No. 63-47918.
According to the publication, in a vane rotary compressor having a structure in which a high-pressure compressed fluid or lubricating oil acts on the back of the vane to bring the vane into contact with the inner wall of the cylinder, in the vane slot, the rotor side surface opening in the vane back space is disclosed. A circumferential groove surrounding the portion is provided in the front side plate and the rear side plate, and a sealing member having a width and a thickness smaller than the width and depth of the circumferential groove is provided in the circumferential groove, and the vane is pressed against the inner wall of the cylinder. To prevent the leakage of high-pressure compressed fluid or lubricating oil into the compression chamber to increase the efficiency of the compressor, and to properly maintain the pressure of the vane on the cylinder inner wall to slide the vane as the rotor rotates. By ensuring the movement, the vane chattering due to the pressure drop at the back of the vane was prevented.

A conventional compressor will be described below with reference to the drawings. FIG. 6 is a sectional view showing a configuration of a cylinder, a vane, a rotor, a sealing member, a front side plate and a rear side plate of a conventional compressor. In FIG. 6, the rotor 4 is arranged with a top gap between it and the cylinder 1, and a vane 8 is inserted into the vane slot 7 of the rotor 4 so as to be retractable. A circumferential groove 17 that surrounds the rotor side surface opening is formed in the front side plate 2, and a sealing member 18 is inserted in the groove. An oil groove 20 is formed in the rear side plate 3 and communicates with the rotor side surface opening to supply the lubricating oil to the back of the vane from the oil sump 15 at the bottom of the oil supply chamber 13 through the oil supply passage 16 to apply pressure. Further, the pressure in the vane slot is also applied to the sealing member 18 and is pressed against the side surface of the rotor due to the pressure difference between the pressure in the compression chamber and the pressure drop due to the leakage of the high-pressure compressed fluid in the vane slot to prevent the vane chattering. did.

FIG. 7 is an enlarged view in which the sealing member 18 in the circumferential groove 17 is arranged. In FIG. 7, the sealing member 1
No. 8 has gaps b, a1 and a2 in the width direction and the depth direction of the circumferential groove.

[0005]

However, in the above structure, in the structure of the compression chamber for compressing the fluid, the rotor and the vanes are driven in the space formed by the cylinder, the front side plate and the rear side plate. It is necessary to secure a minimum gap so that it can slide freely with the front and rear side plates as the shaft rotates, and the sealing member must be deeper than its thickness in the circumferential groove for the sealing member. Therefore, during operation, the sealing member is pressed against the rotor due to the pressure difference between the pressure inside the cylinder and the back pressure of the vane, and the minute gap between the rotor and the front and rear side plates is sealed to prevent vane chattering. The width of the sealing member is smaller than the width of the circumferential groove for the sealing member, and the sealing member is biased in the circumferential groove due to the differential pressure between the cylinder internal pressure and the back pressure of the vane. The sealing member facing the area where the cylinder internal pressure is greater than the vane back pressure is pressed inside the circumferential groove, and the sealing member facing the area where the cylinder internal pressure is less than the vane back pressure is located outside the circumferential groove. It is pressed.

Due to the bias of the sealing member, the sealing member is pressed against the inside of the circumferential groove at a portion where the pressure inside the cylinder is higher than the back pressure of the vane, whereby a gap is formed between the sealing member and the circumferential groove. Will occur. The generated gap serves as a passage that connects the front and rear compression spaces with the vane as a boundary, and the higher compression pressure in the front stroke leaks into the compression chamber in the rear stroke. Due to this leakage, the volumetric efficiency is reduced due to the refrigerant leakage in the preceding stroke, and the compression torque is increased due to the increase in the compression pressure in the subsequent stroke. Therefore, with the conventional sealing member, although the effect of preventing chattering of the vanes is recognized, the effect of improving efficiency is small because the sealing effect is not perfect.

The above problems will be described below with reference to the drawings. FIG. 8 shows a certain point in the compression process of the compressor, in which the refrigerant is compressed by the rotation of the rotor 4 and the force due to the compression pressure is applied to the oil of the rear side plate 3 from the oil reservoir of the oil supply chamber (not shown) through the oil supply passage. The groove 20 acts on the back portion of the vane 8 through the vane slot 7 to allow the vane slot 7 of the rotor 4 to operate.
Leakage occurs from the oil groove 20 of the inside and the rear side plate 3 into the compression chamber 19 due to the pressure difference. In order to reduce this, the sealing member 18 is installed in the circumferential groove 17 of the front side plate 2 or the rear side plate 3, but as shown in FIG. 7, the sealing member 18 and the front side plate 2 or the rear side plate 3 are provided. There are gaps a1, a2, b in both the width and depth directions with the circumferential groove 17 of
Therefore, the sealing member 18 is biased in the circumferential groove due to the pressure difference between the back of the vane and the compression chamber. When the pressure in the compression chamber is higher than the pressure in the back of the vane, the sealing member 18 is pressed against the inside of the circumferential groove 17 and a gap 18b is formed outside the sealing member. This gap 18b serves as a communication path between the compression chambers. A leak 21 between the two occurs.

Therefore, the leakage 21 between the compression chambers causes a decrease in volumetric efficiency and an increase in compression loss due to an increase in compression power.

The present invention is intended to solve the above-mentioned problems of the conventional example, and it is an object of the present invention to prevent a decrease in volumetric efficiency, prevent an increase in compression loss, and improve the efficiency of a compressor.

[0010]

In order to solve the above problems, in the first aspect of the invention, the sealing member has a circumferential groove whose outer diameter is equal to the outer diameter of the circumferential groove, or the difference in thermal expansion between the circumference of the sealing member during operation. The outer diameter is set so that there is no gap between it and the outer diameter of the groove, and the width dimension "Wsc" before assembly is set to the depth "Ws" of the circumferential groove on the front or rear side plate and the front and rear of the rotor. Dimension "Ws + W" with a small gap "Wc" between the side plate
“Wsc> Ws + Wc” is set to be larger than c ”, and the contact portion with the rotor is formed into, for example, a lip shape so as to have elastic force due to the shape and deformed at the time of assembly so that the width dimension of the sealing member has a sealing groove depth and a minute gap. The added dimensions can be made the same.

Further, in the second aspect of the invention, the positions of the circumferential groove and the sealing member are provided on the innermost side so that the vane and the sealing member do not come off when the vane is maximally popped out, and the leak passage in the gap between the circumferential grooves is formed. It was set to be farther from the rotor end face.

In the third aspect of the invention, the oil supply groove to the vane back space provided on the other side plate of the side plate provided with the sealing member is provided inside the inner diameter of the circumferential groove for the seal member.
The inner diameter of the oil supply groove was set so that it would not come into contact with the side plate inside the oil groove when the vane appears and disappears.

Further, in the fourth invention, a circumferential groove is further provided inside the circumferential groove of the side plate and the sealing member provided in the first invention, and an inner diameter smaller than the inner diameter of the circumferential groove is provided in the circumferential groove. Either the size or the difference in thermal expansion is used to set the inner diameter so that no gap is created between it and the inner diameter of the circumferential groove during operation, and the thickness dimension "Wsc" before assembly is the depth of the circumferential groove. ”
The thickness "Wsc> Ws + which is larger than the dimension" Ws + Wc "which is obtained by adding" Ws "and the minute gap" Wc "between the rotor and the side plate.
"Wsc" is set, and the dimensions are changed by deforming at the time of assembling, so that the groove depth and the minute gap become equal to "Wsc".
= Ws + Wc ", the sealing member is provided.

[0014]

According to the first aspect of the present invention, by press-fitting the outside of the sealing member or setting the dimensions by utilizing the difference in thermal expansion, the gap between the outer diameter portion of the sealing member and the circumferential groove is eliminated, and compression is performed. The bias of the sealing member in the circumferential groove due to the pressure difference between the room pressure and the back pressure of the vane is prevented, and the leakage passage in the circumferential groove is not formed, so that the leakage between the compression chambers is prevented.
Further, the thickness dimension "Wsc" before assembly is set to the depth "Ws" of the circumferential groove and the minute gap "W" between the rotor and the side plate.
Thickness "Ws greater than dimension" Ws + Wc "including c"
By setting c> Ws + Wc ”, the dimensions change due to deformation during assembly, and“ Wsc = Ws + Wc ”, which is equal to the sum of the groove depth and the minute gap, and the sealing effect of the sealing member itself is increased. The back pressure can be prevented from leaking into the compression chamber, and the pressing force of the back pressure of the vane can be applied to further improve the sealing effect.

Further, according to the second aspect of the invention, the circumferential groove and the sealing member are provided at the innermost position so that the vane and the sealing member do not come off during the maximum protrusion of the vane. The leakage passage is longer than the rotor end surface, and the leakage length is long, so that the leakage amount can be reduced.

According to the third aspect of the invention, the oil supply groove to the vane back space provided on the other side plate of the side plate provided with the sealing member is provided inside the inner diameter of the circumferential groove for the sealing member.
The inner diameter of the oil supply groove was set so that the rear end of the vane would not come into contact with the side plate inside the oil groove when the vane appears and disappears. As in the first aspect of the present invention, when the sealing effect of the sealing member is improved, the pressure on the side surface of the vane increases due to the increase in the back pressure of the vane, and the force for pressing the vane against the side surface inside the sealing member increases, and the vane appears and disappears. The movement causes the rear end of the vane to fall into the oil groove, causing the other side end to hit the side plate and the edge, thereby damaging the side plate. However, by setting the dimensions as described above, it is possible to prevent the vane from falling into the oil groove, and it is possible to prevent abnormal wear due to edge contact of the vane tip with the side plate.

Further, in the fourth invention, a circumferential groove is further provided inside the circumferential groove of the side plate and the sealing member provided in the first invention, and the inner diameter of the circumferential groove is smaller than the inner diameter of the circumferential groove. The inner diameter is set to the inner diameter by press-fitting or the difference in thermal expansion is used to eliminate the gap between the inner diameter of the sealing member and the circumferential groove, and the thickness before assembly "Wsc"
Is set to a thickness "Wsc> Ws + Wc" larger than the dimension "Ws + Wc", which is obtained by adding the depth "Ws" of the circumferential groove and the minute gap "Wc" between the rotor and the side plate, and by deforming at the time of assembly. A sealing member with "Wsc = Ws + Wc" whose size is changed to be equal to the sum of the groove depth and the minute gap is provided. The inner sealing member is effective in preventing leakage from the outside to the inside, but in the opposite direction. Is not very effective, and similarly, the outer sealing member is effective in preventing leakage from the inner side to the outer side, but is not so effective in leaking in the opposite direction. As a result, the back pressure of the vane is not sealed by the inner sealing member and leaks into the space between the inner and outer sealing members, and the outer sealing member prevents the pressure from leaking into the compression chamber. Therefore, the pressure applied to the sealing member can be stably maintained, and the sealing effect of the sealing member becomes stable. As a result, fluctuations in sealing performance due to fluctuations in compression pressure can be reduced, and stable efficiency improvement can be obtained.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vane rotary compressor according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing the construction of a cylinder, a vane, a rotor, front and rear side plates and a sealing member of a vane rotary compressor according to an embodiment of the first invention. In FIG. 1, a cylinder 1 has a cylindrical inner wall, and both end openings are closed by a front side plate 2 and a rear side plate 3, and the cylinder 1, the front side plate 2, and the rear side plate 3 are connected and fixed so as not to rotate with respect to each other. ing. In the space formed by the cylinder inner wall of the cylinder 1, the front side plate 2 and the rear side plate 3, a rotor 4 is located with its center eccentric to the center of the cylinder inner wall of the cylinder 1. The drive shaft 5 is integrally and concentrically formed with the rotor 4, and is rotatably supported by bearings 6 provided on the front side plate 2 and the rear side plate 3, respectively. A plurality of vane slots 7 are provided on the rotor 4, and the drive shaft 5
It is parallel to the axis of the above and opens at the outer peripheral surface of the rotor 4.
The vane 8 is inserted in the vane slot 7 so as to be retractable. The discharge hole 9 is provided on the high pressure side of the cylinder 1 and opens to the high pressure gas chamber 10, and the discharge hole 9 is provided with a discharge valve 11. The suction hole 12 is the cylinder 1
It is provided on the low pressure side of. The oil supply chamber 13 communicates with the high pressure gas chamber 10 through a passage 14, and an oil sump portion 15 is provided below the oil supply chamber 13. The oil supply passage 16 is an oil supply passage that connects the oil reservoir 15 below the oil supply chamber case 13 to the vane slot 7. An oil groove 20 that communicates with the oil supply passage 16 and supplies oil to the vane slot 7 is provided on the rear side plate. The circumferential groove 17 is provided in the front side plate 2 or the rear side plate 3 and opens on the side surface of the rotor 4. A sealing member 18 is arranged in the circumferential groove 17.

FIG. 2 is a partial sectional view showing before and after the assembling of the sealing member 18 in the circumferential groove 17 provided in the side plate. The sealing member 18 has an outer diameter dimension "φDc" larger than the outer diameter dimension "φDs" of the circumferential groove and is "φDc>φDs", or φDc = φDs during operation by utilizing a thermal expansion difference.
And the width dimension "Wsc" before assembly is set to the depth of the circumferential groove on the front or rear side plate.
Ws "and a minute gap" Wc "between the rotor and the front and rear side plates
"Wsc>W"
s + Wc ", the contact portion with the rotor is formed into a lip shape, for example, so as to have an elastic force due to the shape, so that the width of the sealing member is deformed when assembled and the width dimension of the sealing member can be made equal to the sealing groove depth and a minute gap. The dimensions are set to.

In FIG. 1, power is transmitted to the compressor via an engine (not shown) and a belt (not shown), and the rotor 4
As a result of rotation, the refrigerant containing the lubricating oil is sucked from the suction hole 12 and the cylinder 1, the rotor 4, the vanes 8 and the front side plate 2 are sucked.
The refrigerant is compressed by the compression chamber 19 formed by the rear side plate 3 and discharged from the discharge hole 9 and flows into the oil supply chamber 13 through the high pressure gas chamber 10 and the lubricating oil is separated in the oil supply chamber 13 and sent out to the refrigeration cycle. .

The lubricating oil separated in the oil supply chamber is supplied to the oil supply chamber 13
The oil is stored in the oil sump portion 15 below and is used for pressing the vane 8 through the oil supply passage 16.

When the sealing member 18 is assembled, it is press-fitted on the outside of the circumferential groove so that there is no gap between the circumferential groove and the outside of the sealing member. Further, the minute gap between the front side plate or the rear side plate and the rotor is surely sealed by using the sealing member 18 dimensioned as described above, and is pressed against the side surface of the rotor 4 by the back pressure of the vane. Will increase.

FIG. 3 is a partially enlarged view of the vane maximum protruding position showing an embodiment of the second invention. Circumferential groove 17
The positions of the sealing member 18 and the sealing member 18 are provided on the innermost side at a position where the vane 8 and the sealing member 18 do not come off when the vane 8 pops out at maximum.

FIG. 4 is a sectional view showing an embodiment of the third invention. The oil groove 20 for supplying oil to the vane back space 22 provided on the other side plate (for example, the rear side plate 3) of the side plate provided with the sealing member 18 (for example, the front side plate 2) is replaced with the circumferential groove for the seal member 18. The inner diameter of the oil groove 20 is set to 17 so that the inner diameter of the oil groove 20 is set as follows so that the vane 8 does not come into contact with the side plate inside the oil groove when the vane 8 appears and disappears.

If the inner diameter of the circumferential groove is D1, the outer diameter of the oil groove is D2, and the shortest distance from the center when the vane is closest to the rotor center is R3, and the inner diameter of the oil groove is R4, then D1> D2 R3> R4. To dimension.

FIG. 5 is a partial sectional view showing a circumferential groove, a sealing member and a rotor provided on a side plate of an embodiment of the fourth invention. A circumferential groove 17 'was further provided inside the circumferential groove 17 and the sealing member 18 of the side plate provided in the first invention, and a sealing member 18' was provided in the circumferential groove 17 '. The sealing member 18 'has an inner diameter smaller than the inner diameter of the circumferential groove, or is dimensioned so that a gap between the inner diameter of the sealing member and the circumferential groove does not occur during operation by utilizing a thermal expansion difference. As with the sealing member 18, the thickness "Wsc" before assembly is added to the depth "Ws" of the circumferential groove and the small gap "Wc" between the rotor and the side plate "Ws + W".
Set the thickness "Wsc> Ws + Wc" larger than c ",
The dimensions are changed by deformation during assembly, and the dimensions are set so as to be “Wsc = Ws + Wc” which is equal to the total of the groove depth and the minute gap.

[0028]

As is apparent from the above description, the first,
According to the second and fourth aspects of the invention, the sealing member is press-fitted into the circumferential groove, or the thermal expansion difference is used to set the dimension so that a radial gap between the sealing member and the circumferential groove does not occur during operation. , It was possible to improve the sealing effect by preventing the compression pressure from leaking by making contact with the rotor during assembly, improve the volumetric efficiency and improve the efficiency of the compressor by reducing the compression power. At the same time, the back pressure of the vane is maintained, which is effective in preventing vane chattering.

In the third aspect of the invention, since the sealing effect of the sealing member is improved as described above, the back pressure of the vane can be maintained at a pressure higher than the conventional pressure. It is conceivable that the increase in the pressure on the inner side of the sealing member causes the rear end of the vane to fall into the oil groove and tilt and the tip of the side surface on the opposite side to make edge contact with the side plate when the vane moves in and out. By setting the inner diameter so that the rear end of the vane is not covered when the vane appears and disappears, edge contact of the tip of the vane due to the inclination of the vane can be prevented, abnormal wear of the side plate can be prevented, and durability was also satisfied.

[Brief description of drawings]

FIG. 1A is a vertical sectional view showing a compressor according to a first embodiment of the present invention, and FIG. 1B is a horizontal sectional view thereof.

FIG. 2 (a) is a cross-sectional view of a main part of a circumferential groove provided in a side plate of the compressor before assembly of a sealing member, and FIG. 2 (b) is a cross-sectional view of a main part when the sealing member is assembled.

FIG. 3 is an enlarged sectional view of a main part of a compressor according to a second embodiment of the present invention.

FIG. 4A is a sectional view showing a compressor according to a third embodiment of the present invention, and FIG. 4B is an enlarged sectional view showing the same part.

FIG. 5 is a cross-sectional view of an essential part showing a time of assembling a sealing member in a circumferential groove provided in a side plate in a fourth embodiment of the present invention.

FIG. 6A is a longitudinal sectional view showing a conventional compressor, and FIG. 6B is a transverse sectional view thereof.

FIG. 7 is a cross-sectional view of essential parts showing a sealing member in a circumferential groove of a conventional compressor.

FIG. 8A is a cross-sectional view showing a compression leak of a conventional compressor, and FIG. 8B is an enlarged view of the relevant part.

[Explanation of symbols]

 1 Cylinder 2 Front Side Plate 3 Rear Side Plate 4 Rotor 5 Drive Shaft 6 Bearing 7 Vane Slot 8 Vane 9 Discharge Hole 10 High Pressure Gas Chamber 11 Discharge Valve 12 Suction Hole 13 Oil Supply Chamber 14 Passage 15 Oil Sump 16 Oil Supply Passage 17 Circumferential Groove 18 Sealing member 18b Gap 19 Compression chamber 20 Oil groove 21 Leakage between compression chambers 22 Vane back space

Claims (4)

[Claims] 1. A cylinder having a cylindrical inner wall, a front side plate and a rear side plate which form a closed space by closing both ends of the cylinder, and a cylinder of the cylinder which is arranged in this space. -Shaped inner wall, a rotatable rotor that forms a compression chamber with the front side plate and the rear side plate, a plurality of vanes slidably inserted in vane slots provided in the rotor, the front side plate and the rear part A compression mechanism section is constituted by a drive shaft which is rotatably supported by bearings respectively arranged on the side plates and is integrally and concentrically arranged with the rotor and transmits power, and is compressed by the compression mechanism section. The lubricating oil in the high-pressure fluid is separated, and an oil supply chamber case having an oil sump portion is arranged in a lower portion thereof, and an oil supply passage is provided which connects the oil sump portion of the oil supply case and the vane slot. In the vane rotary compressor is provided with a circumferential groove surrounding the rotor side opening of the vane back space of the vane slot to the front side plate or rear plate,
Set an outer diameter larger than the outer diameter of the circumferential groove in the circumferential groove, or set an outer diameter dimension that does not create a gap with the outer diameter of the circumferential groove during operation by utilizing the difference in thermal expansion. , And the thickness dimension “Wsc” before assembly is the depth “Ws” of the circumferential groove.
"Wsc + Ws + W", which is larger than the dimension "Ws + Wc" including the small gap "Wc" between the rotor and the side plate
By setting it to "c" and deforming at the time of assembly, the thickness becomes equal to the total of the groove depth and the minute gap "Wsc = W"
A vane rotary compressor provided with a sealing member such as "s + Wc". 2. The vane rotary compressor according to claim 1, wherein the circumferential groove and the sealing member are provided on the innermost side at a position where the vane and the sealing member do not come off even when the vane is fully popped out. 3. An oil supply groove to the back space of the vane provided on the other side plate of the side plate provided with the sealing member is provided inside the circumferential groove for the sealing member, and the inner diameter of the oil supply groove is set when the vane appears and disappears. The vane rotary compressor according to claim 1, wherein the dimension is set so that the side plate on the inner side of the oil groove does not come into contact with. 4. A circumferential groove is further provided inside the circumferential groove of the side plate and the sealing member, and the inner circumferential dimension of the circumferential groove is smaller than the inner circumferential dimension of the circumferential groove, or the difference in thermal expansion is utilized. The inner diameter is set so that no gap is created between it and the inner diameter of the circumferential groove during operation, and the thickness dimension "Wsc" before assembly is set between the depth "Ws" of the circumferential groove and the rotor and the side plate. Minute gap "
Thickness "Ws larger than" Ws + Wc "including Wc""W
sc> Ws + Wc ", and the sealing member is provided such that" Wsc = Ws + Wc "is set so that the thickness dimension changes by being deformed at the time of assembling so that it becomes equal to the total of the groove depth and the minute gap. The vane rotary compressor according to 1.