JPH0617772A - Scroll compressor - Google Patents

Abstract

PURPOSE:To improve sealing ability and enhance assembly workability of a scroll by reducing a starting load as a problem due to liquid compression is prevented from arising and besides setting the press force of a fixed scroll to an arbitrary value. CONSTITUTION:A fixed scroll 2 is movable in a direction in which it is separated away from a moving scroll 3, and an oil storage chamber 16 is formed on the back side of the fixed scroll 2. The oil storage chamber 16 is provided with an oil feed pump 18 to feed oil and a relief passage 19 through which oil fed to the oil storage chamber 16 is returned to a chamber 8 on the low pressure side partitioned from a delivery chamber 6, and a relief valve 20 is located in the relief passage 19. This constitution reduces a starting load as a problem due to liquid compression is prevented from arising and besides improves sealing ability and facilitates assembly of a scroll.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor, and more particularly to a scroll compressor having a fixed scroll and a movable scroll, and the orbiting movement of the movable scroll.

[0002]

2. Description of the Related Art Conventionally, as disclosed in Japanese Patent Laid-Open No. 63-80088, there has been proposed a scroll compressor capable of improving the sealing property while coping with liquid compression. As shown in FIG. 4, this conventional compressor has a fixed scroll A having a spiral casing A1 and a discharge port A2 formed on the center side of the spiral casing 1 in a closed casing 1.
And a scroll B that meshes with the scroll A1 of the fixed scroll A.
Movable scroll B having 1 and this movable scroll B
A motor M having a drive shaft C for driving the motor M and a bearing housing D having a thrust receiving surface facing the back surface of the movable scroll B are internally provided, and the fixed scroll A is separated from the movable scroll B. While being movable,
A partition wall F defining a discharge chamber E communicating with the discharge port A1 is provided on the back side of the fixed scroll A, and the fixed scroll A is provided between the partition wall F and the back surface of the fixed scroll A. Is provided in the direction of the movable scroll B, and the fixed scroll A is pressed against the movable scroll B to move the fixed scroll A and the flexible scroll B.
It is configured so as to improve the sealing property between and.

[0003]

According to this conventional compressor, the fixed scroll A is elastically pressed against the movable scroll B by the leaf spring G.
When the pressure of the working space becomes high as in the case where liquid compression is performed, the fixed scroll A moves in the direction away from the movable scroll B, and the problem due to the liquid compression can be avoided. Since the leaf spring G constantly presses the fixed scroll A, the leaf spring G is pressed toward the movable scroll even when the compressor is stopped, and therefore, when the compressor is started from the stopped state,
There is a problem that the starting load becomes high, and since the fixed scroll A is pressed by the leaf spring G, the pressing force is determined by the spring constant of the leaf spring G, so that only variations occur. There is also a problem that the pressing force cannot be properly adjusted with respect to the pressure change in the working space,
Further, when the scrolls A and B are assembled, the leaf spring G
Since it is necessary to bend and assemble the assembly, there is a problem that assembly workability is poor.

The present invention has been made in view of the above points.
The purpose is to be able to improve the sealing performance because the problem due to liquid compression can be avoided, yet the starting load can be reduced, and
The pressing force of the fixed scroll can be set arbitrarily and appropriately, and the workability of assembling the scroll can be improved.

[0005]

According to the present invention, therefore, a fixed scroll 2 having a discharge port 2b on the center side, a movable scroll 3 meshing with the fixed scroll 2 and the movable scroll 3 are provided in a casing 1. A drive shaft 4 for driving is internally provided, and the discharge port 2 is provided on the back side of the fixed scroll 2.
A scroll compressor provided with a partition wall 7 that defines a discharge chamber 6 communicating with b, wherein the fixed scroll 2 is movable in a direction away from the movable scroll 3, and the fixed scroll 2 and the partition are provided. Oil storage chamber 1 between wall 7
6 and a relief passage 18 for returning the oil supplied to the oil storage chamber 16 to the low pressure side chamber 8 defined by the discharge chamber 6 and the oil supply pump 18 for supplying the oil to the oil storage chamber 16. 19 and the relief valve 20 is provided in the relief passage 19.

Further, it is preferable that the drive shaft 4 is provided with an oil supply passage 13 communicating with the lubricating pump 14, and the oil supply passage 13 is communicated with the oil storage chamber 16.

[0007]

Since the oil storage chamber 16 on the rear side of the fixed scroll is supplied with oil pressure to press the fixed scroll 2 against the movable scroll 3, the fixed scroll 2 is pressed against the movable scroll 3 when the operation is stopped. Since it can be started in this state, the starting load can be reduced. Further, when the pressure in the working space between the fixed scroll 2 and the movable scroll 3 rises due to liquid compression during operation, etc., when the fixed scroll 2 is pressed in the direction away from the movable scroll 3, the oil storage The chamber 16 is pressurized and its hydraulic pressure rises, the relief valve 20 is opened, and the back pressure set by the relief valve 20 is adjusted. The fixed scroll 2 moves as the pressure in the working space increases. The scroll 3 moves in the direction away from the scroll 3, and the pressure increase in the working space can be suppressed, and the problem due to the liquid compression can be avoided.

Further, the oil pressure in the oil storage chamber 16, that is,
Since the back pressure of the fixed scroll 2 can be arbitrarily set by setting the relief pressure of the relief valve 20, the pressing force of the fixed scroll 2 can be arbitrarily set, so that the bending of the end plate of the fixed scroll 2 can be prevented by the fixed scroll. 2 can be set so that the clearance between the scroll body and the end of the scroll of the orbiting scroll 3 can be reduced, and the sealability can be improved. Further, when the scroll is assembled, the leaf spring is bent as in the conventional example. Since it is not necessary to assemble, the workability of assembling the scroll can be improved, and the cost can be reduced.

Further, when the drive shaft 4 is provided with an oil supply passage 13 communicating with the lubrication pump 14, and the oil supply passage 13 is communicated with the oil storage chamber 16, a special oil supply pump is not provided. The lubrication pump 14 can be used to supply oil to the oil storage chamber 16, the oil passage structure to the oil storage chamber 16 can be simplified, and the cost can be further reduced.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The scroll compressor shown in FIG. 1 mainly compresses a refrigerant in a refrigerating machine, and a scroll body 2a is provided inside a cylindrical closed horizontal casing 1 on one side in the length direction.
And a movable scroll 3 having a fixed scroll 2 having a discharge port 2b formed on the center side of the scroll 2a, and a movable scroll 3 having a scroll 3a meshing with the scroll 2a of the fixed scroll 2. Inside the side, the movable scroll 3
Is equipped with a motor 5 having a drive shaft 4 for orbiting
A partition wall 7 that defines a discharge chamber 6 that communicates with the discharge port 2b is provided on the back side of the fixed scroll 2, and a central portion of the partition wall 7 is a back surface from around the discharge port 2a of the fixed scroll 2. A fitting concave portion 7a for receiving the protruding cylindrical portion 2c protruding to the side is provided so that the pressure of the high pressure gas discharged from the discharge port 2b acts only on the center side of the fixed scroll 2. Further, in the low pressure side chamber 8 partitioned from the discharge chamber 6, a first bearing housing 9 fixed to the casing 1 is provided on the back side of the movable scroll 3,
The back surface of the movable scroll 3 is supported on the first bearing housing 9 via a thrust bearing 9a.
The scroll side of the drive shaft 4 is supported by a bearing 9b of a bearing housing 9, and an eccentric shaft portion 4a is provided at an end portion of the drive shaft 4 on the scroll side. It is supported via a metal bearing 10 in a cylindrical boss portion 3b provided on the rear surface of the.

A second bearing housing 1 having a ball bearing 11 for supporting the anti-scroll side of the drive shaft 4 is provided on the anti-scroll side of the motor 5 in the low pressure side chamber 8.
The second bearing housing 12 is provided with a lubricating pump 14, for example, of a trochoid type for supplying lubricating oil to an oil supply passage 13 formed in the axial center portion of the drive shaft 4, and a suction port of the lubricating pump 14. Is opened to the oil sump 1a at the bottom of the casing 1 through the oil absorption pipe 15.

In the scroll compressor constructed as described above, the embodiment shown in FIGS. 1 to 3 makes the fixed scroll 2 movable in the direction away from the movable scroll 3, and the fixed scroll 2 and the An oil storage chamber 16 is defined between the fixed scroll 2 and the partition wall 7, and the outer peripheral end surface of the fixed scroll 2 on the scroll body 2a side is brought into contact with the outer peripheral end surface of the first bearing housing 9. And a first bearing housing 9 are provided with an oil passage 17 that communicates the oil storage chamber 16 with the oil supply passage 13 of the drive shaft 4, and the lubrication pump 14 supplies oil to the oil storage chamber 16. A relief passage for returning the oil storage chamber 16 to the low pressure side chamber 8 defined by the discharge chamber 6 in the fixed scroll 2 and the first bearing housing 9 while being used also as the pump 18. 9, a relief valve 20 is provided in the relief passage 19, the pressure in the working space between the scrolls 2 and 3 rises above a predetermined pressure due to liquid compression or the like, and the fixed scroll 2 is moved relative to the movable scroll 3. When the pressure of the oil storage chamber 16 is increased by being pressed in the separating direction, the relief valve 20 is opened.

The fixed scroll 2 has a circular outer peripheral surface facing the inner peripheral surface of the casing 1, and the protruding cylindrical portion 2c is movably fitted in the fitting concave portion 7a, while the fixed scroll 2 and the fixed scroll 2 are in contact with each other. A plurality of positioning holes (not shown) are provided on each surface facing the first bearing housing 9, and positioning pins (not shown) fitted into these positioning holes prevent rotation of the fixed scroll 2. The movable scroll 3 can be moved only in the separating direction.

Further, the oil supply passage 13 is formed from one end of the drive shaft 4 to the other end thereof, and the branch passage 1 which opens to the inner peripheral surface of the bearing 9b is provided on the scroll side of the oil supply passage 13.
3a is provided to supply the oil fed from the lubrication pump 14 to the bearings 9b and 10, and
An annular groove 9c communicating with the branch passage 13a and an axial groove 9d axially extending from the annular groove 9c are provided on the inner peripheral surface of the bearing 9b, and the axial groove 9d is inserted through the through hole 9e. Oil is communicated with the oil passage 17, and the oil fed from the lubrication pump 14 to the oil passage 13 is supplied to the oil passage 17 from the bearing 9b.

Further, the oil passage 17 has a first hole 17a extending radially outward from the bearing 9b portion of the first bearing housing 9 and the first hole 17a, as shown in an enlarged view in FIG. Second extending axially from the tip of the
The hole 17b, the third hole 17c extending further in the radial direction from the middle of the second hole 17b, and the third hole 17c.
Fourth hole 17d extending further in the axial direction from the tip of the
And a fifth hole 17e penetrating the fixed scroll 2, and a tube 21 is fixed to one of the fourth hole 17d and the fifth hole 17e, and the tip end side of the tube 21 is set to the inner peripheral surface. It is inserted in the other hole having the seal material so as to be relatively movable.

The relief passage 19 has a first hole 19b formed in the fixed scroll 2 and a second hole formed in the first bearing housing 9, as shown in an enlarged view in FIG.
The first hole 19b and the second hole 19b.
The tube 22 is fixed to one of the
The tip end side of is inserted into the other hole having a seal material on the inner peripheral surface so as to be relatively movable. Further, a valve chamber 19e having a valve seat 19d is provided in the middle of the second hole 19b, and the relief valve 20 biased toward the valve seat by a valve spring 23 is installed in the valve chamber 19e. Together with the valve spring 2
3 is received by the pressure adjusting screw 24, and the pressure adjusting screw 24
The relief pressure of the relief valve 20 can be adjusted by the operation.

The lubricating pump 14 is mainly composed of a trochoid type pump having a pump inner 14a and a pump outer 14b, and is operated in association with the rotation of the drive shaft 4. That is, the drive shaft 4
, A stepped tubular presser foot 25 for pressing down the inner ring 11a of the ball bearing 11 is fitted into the presser foot 25 and integrally rotatably coupled thereto.
Two pump housings 26 are arranged to fix the pump housing 26 in the cylindrical boss portion of the second bearing housing 12, and the pump inner 14a and the pump outer 14 are provided in the inner cavity of the pump housing 26.
b is provided inside, and an end plate 27 for closing the inner cavity portion of the housing 26 is provided on the open side of the pump housing 26, and a discharge passage 28 provided in the end plate 27 is provided with the presser 2
The oil passage 15 is connected to the discharge passage 29 provided in the central portion of the No. 5, and the oil absorption pipe 15 is connected to the end plate 27.

Further, in FIG. 1, 30 is an Oldham coupling provided between the first bearing housing 9 and the back surface of the movable scroll 3 to prevent the movable scroll 3 from rotating and revolve, and 31 is the low pressure joint. A suction pipe opening to the side chamber 8 and a discharge pipe 32 opening to the discharge chamber 6.

Next, the operation of the embodiment configured as described above will be described.

In this embodiment, when the drive shaft 4 is driven by the motor 5, the movable scroll 3 revolves around and the gas refrigerant sucked from the suction pipe 31 into the low pressure side chamber 8 is fixed to the movable scroll 3. It is sucked into the working space formed between the scrolls 2 and 3 from the suction port between the scroll 2 and compressed by the orbital motion of the movable scroll 3, and the discharge port 2b of the fixed scroll 2 and the partition wall. It is discharged into the discharge chamber 6 through the check valve 33 provided in 7, and is discharged outside through the discharge pipe 32.

Further, the lubrication pump 14 is operated by the drive of the drive shaft 4, and the oil stored in the oil sump 1a is sucked by the operation of the lubrication pump 14, and is discharged from the discharge passage 29 to the oil supply passage 13. Lubricating oil is supplied and lubricating oil is supplied to lubrication points such as the bearings 9b and 10, and is further lubricated from the bearing 9b portion to the oil storage chamber 16 via the oil passage 17, and the oil storage chamber 16 is set by the relief valve 20. The set pressure acts on the fixed scroll 2 during operation. In this case, the relief valve 20 and the valve seat 19 are
Even if a clearance is provided between the relief valve 20 and the relief valve 20, a part of the oil supplied to the oil storage chamber 16 is constantly returned from the relief passage 19 to the low pressure side chamber 8. Good.

Since the oil storage chamber 16 is at a low pressure when the compressor is started, the fixed scroll 2 can be started with a small pressing force, and therefore the starting load can be reduced. .

Further, when the pressure in the working space between the fixed scroll 2 and the movable scroll 3 during operation rises due to liquid compression or the like, the fixed scroll 2 moves the movable scroll 3
In contrast to this, since the force pressed in the separating direction becomes large, the oil storage chamber 16 is pressurized and its hydraulic pressure rises, and the relief valve 2
0 opens and is adjusted to the back pressure set by the relief valve 20, and the fixed scroll 2 moves in the direction away from the movable scroll 3 as the pressure in the working space rises. A lap gap is formed between the fixed scroll 2 and the movable scroll 3 due to the movement of the above, and the refrigerant in the working space where the liquid compression is performed leaks to the adjacent low pressure side working space and suction side, and the pressure rise can be suppressed. The problem of liquid compression can be avoided.

Further, the oil pressure in the oil storage chamber 16 can be arbitrarily determined by operating the pressure adjusting screw 24 to set the relief pressure of the relief valve 20.
The pressing force of the fixed scroll 2 can be set arbitrarily, and therefore, the sealing property can be improved by selecting an appropriate pressing force, and since it is not necessary to bend and assemble the leaf spring when assembling the scroll, The workability of assembling the scrolls 2 and 3 can be improved, and the cost can be reduced.

Further, when the lubrication pump 14 that supplies oil to the bearing 9b that supports the drive shaft 4 also serves as the oil supply pump 18 that supplies oil to the oil storage chamber 16, compared to the case where a dedicated oil supply pump is provided. The number of parts can be reduced, and further, since the oil supply chamber 13 can be used to supply oil to the oil storage chamber 16, the passage structure can be simplified and the cost can be further reduced. .

In the embodiment described above, the lubrication pump 14 is also used as the oil supply pump 18, but in addition to this, for example, the lubrication pump 14 is provided with a trochoid type oil supply which rotates in association with the rotation of the drive shaft 4. Like installing pumps side by side,
Alternatively, the first bearing housing 9 is provided with an oil supply pump that rotates in association with the rotation of the drive shaft 4, and the oil sump 1
The oil drawn from a may be supplied to the oil storage chamber 16 via an oil passage provided separately from the oil supply passage 13. The lubrication pump 14 may be a trochoid type oil supply pump, but may be another positive displacement pump such as a yoke type oil supply pump.

Further, the compressor of the present invention may be a horizontal type in which the casing 1 is placed horizontally as shown in FIG. 1, or may be a vertical type in which the casing 1 is placed vertically.

[0028]

As described above, according to the present invention, the fixed scroll 2 can be moved in the direction away from the movable scroll 3,
An oil storage chamber 16 is defined on the back side of the fixed scroll 2, and an oil supply pump 18 for supplying oil to the oil storage chamber 16;
Since a relief passage 19 for returning the oil supplied to the storage chamber 16 to the discharge chamber 6 and the low-pressure side chamber 8 defined by the discharge chamber 6 is provided, and the relief valve 20 is provided in the relief passage 19, the operation is stopped when the operation is stopped. Since the fixed scroll 2 is not pressed by the movable scroll 3, the fixed scroll 2 can be started in this unpressed state, so that the starting load can be reduced. Moreover, when the pressure in the working space between the fixed scroll 2 and the movable scroll 3 rises due to liquid compression or the like, the fixed scroll 2 is moved in the direction away from the movable scroll 3 to increase the pressure in the working space. Since it is suppressed, the problem due to the liquid compression can be avoided.

Further, the oil pressure in the oil storage chamber 16, that is,
Since the back pressure of the fixed scroll 2 can be set arbitrarily by setting the relief pressure of the relief valve 20, the pressing force of the fixed scroll 2 can be set arbitrarily, and the sealing property can be improved by appropriately selecting this pressing force. In addition, when assembling the scroll, it is not necessary to bend and assemble the leaf spring as in the conventional example, so that the workability of assembling the scroll can be improved and the cost can be reduced.

Further, when the drive shaft 4 is provided with an oil supply passage 13 communicating with the lubricating pump 14 and the oil supply passage 13 is communicated with the oil storage chamber 16, a special oil supply pump is not provided. The lubrication pump 14 can be used to supply oil to the oil storage chamber 16, the oil passage structure to the oil storage chamber 16 can be simplified, and the cost can be further reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of a compressor of the present invention.

FIG. 2 is an enlarged cross-sectional view of only the main part.

FIG. 3 is an enlarged cross-sectional view of only the relief valve side portion.

FIG. 4 is a partially omitted cross-sectional view of a conventional compressor.

[Explanation of symbols]

 1 Casing 2 Fixed Scroll 2a Discharge Port 3 Movable Scroll 4 Drive Shaft 6 Discharge Chamber 7 Partition Wall 8 Low Pressure Side Chamber 13 Lubrication Passage 14 Lubrication Pump 16 Oil Storage Chamber 19 Relief Passage 20 Relief Valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazutoshi Yamada 3-12 Tsukiko Shinmachi, Sakai City, Osaka Prefecture Daikin Industries, Ltd. Sakai Manufacturing Co., Ltd. inside the seaside factory (72) Inventor Toshiaki Yoshii 3 12 Chikiko Shinmachi, Sakai City, Osaka Prefecture Address Daikin Industrial Co., Ltd. Sakai Plant inside the seaside factory

Claims (2)

[Claims] 1. A casing 1 is internally provided with a fixed scroll 2 having a discharge port 2b on the center side, a movable scroll 3 meshing with the fixed scroll 2 and a drive shaft 4 for driving the movable scroll 3, and A scroll compressor having a partition wall 7 defining a discharge chamber 6 communicating with the discharge port 2b on the back side of the fixed scroll 2, the fixed scroll 2 being away from the movable scroll 3. The oil storage chamber 16 is made movable and defines an oil storage chamber 16 between the fixed scroll 2 and the partition wall 7.
6, an oil supply pump 18 for supplying oil to 6, and the oil storage chamber 16
A scroll compressor, comprising: a relief passage 19 for returning the oil supplied to the discharge chamber 6 to a low-pressure side chamber 8 partitioned from the discharge chamber 6, and a relief valve 20 provided in the relief passage 19. 2. The drive shaft 4 is provided with an oil supply passage 13 communicating with a lubricating pump 14, and the oil supply passage 13 is provided in the oil storage chamber 16.
The scroll compressor according to claim 1, which is in communication with the scroll compressor.