JPH0415995Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of the invention] The present invention relates to a rotary compressor that is incorporated into refrigerators, air conditioners, etc. This invention relates to a rotary compressor that reduces the startup load when restarting.

[Technical background of the invention and its problems]

Conventionally, in rotary compressors, the pressure between the high-pressure side and the low-pressure side when the operation is stopped is balanced through the clearance between the main bearing and the sub-bearing of the compression element and the roller end face, reducing the startup load when restarting. I was trying to do that. However, in order to improve the pressure balance characteristics, the clearance must be increased to a certain extent, which has the drawback that during operation, refrigerant on the high pressure side leaks to the low pressure side, resulting in a reduction in compression efficiency. In addition, if the clearance is made smaller in order to improve the compression efficiency, the pressure balance characteristics at the time of shutdown will deteriorate, making it impossible to maintain a sufficient pressure balance between the high pressure side and the low pressure side, and the startup load will increase. In order to increase the starting torque of the electric element, it is necessary to increase the starting torque of the electric element by using expensive electrical equipment. Furthermore, it is also known to use a pressure regulator to balance the pressure at the time of shutdown, as shown in, for example, Japanese Utility Model Application Publication No. 51-124905. There were drawbacks that increased significantly.

[Purpose of the invention] The invention was made based on the above circumstances,
A rotary compressor that can reduce the startup load when restarting by balancing the pressure between the high pressure side and the low pressure side when the operation is stopped, without reducing compression efficiency or using a complicated pressure adjustment device. is intended to provide.

[Summary of the idea]

In the present invention, a groove is formed in at least one of the abutting part between the cylinder block and the main bearing of the compression element and the abutting part between the cylinder block and the sub-bearing, and one end is formed between the wall surface of the blade groove on the low pressure chamber side and the blade. A communication passage is formed that opens facing the sliding clearance and the other end opens into the space inside the sealed case above the lubricating oil level.When the operation is stopped, high-pressure refrigerant inside the sealed case flows into the communication passage. From there, it flows into the low pressure chamber of the cylinder chamber through the clearance between the wall surface of the blade groove on the low pressure chamber side and the side surface of the blade, thereby achieving pressure balance between the high pressure side and the low pressure side.

[Example of idea]

A rotary compressor according to an embodiment of the present invention will be described in detail with reference to the drawings. As shown in FIGS. 1 and 2, the rotary compressor is constructed by housing an electric element 3 and a compression element 4 in a closed case 2 in which lubricating oil 1 is stored at the bottom. The electric element 3 includes a stator 2a that is press-fitted into the inner wall of the sealed case 2, and this stator 2a.
and a rotor 2b fixed to the rotating shaft 5 on the inner circumference thereof. On the other hand, the compression element 4 is attached to a cylinder block 6 which is fixed to the inner wall of the sealed case 2 by means such as welding and has a cylindrical cylinder chamber 6a, and is attached to both sides of the cylinder block 6, and is attached to the rotation shaft 5. A main bearing 7 and a sub-bearing 8 that pivotally support the cylinder chamber 6a and seal the cylinder chamber 6a, and the rotation shaft 5 within the cylinder chamber 6a.
a roller 9 that is fitted into the eccentric portion 5a and rotates eccentrically within the cylinder chamber 6a; and a blade groove 1 formed in the cylinder block 6 in the radial direction.
It is slidably provided in the cylinder chamber 6a and contacts the outer circumferential surface of the roller 9 under the pressure of the spring 11, and connects the low pressure chamber 6b on the suction hole 12 side and the discharge hole 1 in the cylinder chamber 6a.
It is provided with a blade 14 that partitions into a high pressure chamber 6c on the third side. Further, the rotary shaft 5 has an oil supply hole 5b formed in its shaft core, and a plurality of communication holes 5c that communicate with the oil supply hole 5b and open on the outer peripheral surface of the rotary shaft 5. , said blade 1
Each sliding portion is supplied with lubricating oil 1 supplied via an oil supply pipe 16 from a well-known blade oil pump device 15 that utilizes the reciprocating motion of a blade oil pump 15.
Further, as shown in FIG. 3, a groove 8a is formed in the abutment surface of the secondary bearing 8 with the cylinder block 6, and by closing this groove 8a with the cylinder block 6, one end 17a is connected to the blade groove. A communication passage 17 opens facing the sliding clearance between the blade 14 and the wall surface 10a on the low pressure chamber 6b side of 10, and the other end 17b opens into the internal space of the sealed case 2 above the oil level 1a of the lubricating oil 1. is formed. Note that 18 is a suction pipe, and 19 is a discharge pipe.

Next, the operation of the above embodiment will be explained. By energizing the electric element 3, the rotor 2b and the rotating shaft 5 rotate integrally, and a well-known compression operation is performed. That is, refrigerant is sucked into the cylinder chamber 6a through the suction pipe 18 and the suction hole 12, compressed within the cylinder chamber 6a, and discharged from the discharge hole 13 into the space inside the sealed case. Furthermore, this discharged refrigerant is discharged to the outside from the discharge pipe 19. During this compression operation, as shown in FIG. 4, the blade 14 is tilted by the force F caused by the pressure difference between the low pressure chamber 6b and the high pressure chamber 6c of the cylinder chamber 6a, and the blade 14 and the blade groove 10 on the low pressure chamber 6b side are tilted. The cylinder chamber side open end 10b of the wall surface 10a is in contact with the blade groove 10, and lubricating oil is supplied to the blade groove 10 from the back side of the blade 14 to form an oil film. The high pressure refrigerant inside the low pressure chamber 6
It does not flow into b. On the other hand, when the operation is stopped, as shown in FIG. 5, the force F due to the pressure difference is released and the supply of lubricating oil to the blade groove 10 is also stopped. The high-pressure refrigerant flows into the low-pressure chamber 6b through the sliding clearance between the blade 14 and the side surface 10a of the blade groove 10 on the low-pressure chamber side, thereby achieving a pressure balance between the high-pressure side and the low-pressure side. Therefore, at the time of restart, the system is started in a state where there is no pressure difference between the high pressure side and the low pressure side, and the start-up load can be reduced.

Note that the other end 17b of the communication path 17 is connected to the lubricating oil 1.
If the opening is below the oil level in the low pressure chamber 6, even though the pressure balance between the high pressure side and the low pressure side can be achieved when the operation is stopped, the low pressure chamber 6
A large amount of lubricating oil flows into the inner part b, causing liquid compression upon restart, causing a problem. However, in the embodiment described above, the secondary bearing 8 is made of iron-based sintered alloy, and the groove is formed during molding. Since the grooves 8a can be freely formed by simultaneously molding the grooves 8a, the other end 17b of the communication passage 17 is placed above the lubricating oil level 1a even in a rotary compressor where the lubricating oil level 1a is relatively high. It can be easily opened.

FIG. 6 shows another embodiment of the present invention.
A groove 6 is formed on the contact surface of the cylinder block 6 with the secondary bearing 8.
By forming a groove 6d and closing this groove 6d with a sub-bearing 8, a communication passage 17 is formed, and the same effect can be obtained.

Note that the present invention is not limited to the above-mentioned embodiment, and the sub bearing 8
A communication path may be formed by providing grooves 8a and 6d in both the cylinder block 6 and the cylinder block 6 (that is, by combining the embodiment shown in FIG. 3 and the embodiment shown in FIG. 6). Further, in each of the above embodiments, a groove is provided in the abutment part between the sub bearing 8 and the cylinder block 6 to form the communication passage 17, but the groove is provided in the abutment part between the main bearing 7 and the cylinder block 6. A groove may be provided to form a communication path. Furthermore,
Grooves may be formed in both the abutting surfaces of the sub bearing and the cylinder block and the abutting surfaces of the main bearing and the cylinder block to form communication passages. Furthermore, it goes without saying that the present invention is applicable not only to horizontal rotary compressors but also to vertical rotary compressors. In the case of a vertical rotary compressor, it is preferable to form a groove in the abutment area between the main bearing and the cylinder block, which is disposed above the lubricating oil level, to form a communication path.

[Effect of idea]

As explained above, in the present invention, a groove is formed in at least one of the abutment part between the cylinder block and the main bearing of the compression element and the abutment part between the cylinder block and the sub-bearing, and one end is formed in the wall surface of the blade groove on the low pressure chamber side. A communicating path is formed that opens facing the sliding clearance between the lubricating oil and the blade, and the other end opens into the internal space of the sealed case above the lubricating oil level, so it can be operated without using a pressure regulator etc. It is possible to balance the pressure between the high pressure side and the low pressure side when the system is stopped, and it is possible to reduce the starting load when restarting the system. Furthermore, since the clearance between the main bearing, the sub-bearing and the roller end face is not utilized, these clearances can be reduced to improve compression efficiency during operation.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of a rotary compressor according to an embodiment of the present invention, and FIG.
A′ sectional view, FIG. 3 is an enlarged sectional view of the main part taken along line B-B′ in FIG. 1, FIG. 4 is an explanatory diagram showing the state of the blade during operation, and FIG. FIG. 6 is a side view of a main part of a rotary compressor according to another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Lubricating oil, 2... Sealing case, 4... Compression element, 5... Rotating shaft, 5a... Eccentric part, 6... Cylinder block, 6a... Cylinder chamber, 6b...
Low pressure chamber, 6c... High pressure chamber, 7... Main bearing, 8...
Secondary bearing, 9...Roller, 10...Blade groove, 1
4...Blade, 17...Communication path.

Claims (1)

[Scope of utility model registration request] A cylinder block having a cylindrical cylinder chamber, a main bearing and a sub-bearing attached to both sides of the cylinder block, a roller fitted to an eccentric portion of a rotating shaft in the cylinder chamber, and the cylinder. A compression element, which includes a blade provided in a blade groove formed in the block and abutting against the outer circumferential surface of the roller to partition the cylinder chamber into a low pressure chamber and a high pressure chamber, is placed in a sealed case with lubricating oil stored at the bottom. In the rotary compressor, the refrigerant compressed by the compression element is discharged through the airtight case interior space, and the cylinder block and the main bearing of the compression element are in contact with each other, and the cylinder block and the sub- A groove is formed in at least one of the abutting parts of the bearing, one end is open facing the sliding clearance between the blade and the wall surface on the low pressure chamber side of the blade groove, and the other end is sealed above the lubricating oil level. A rotary compressor characterized by forming a communication path that opens into a space inside the case.