JPH0772547B2 - Rolling piston compressor - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-pressure container type rolling piston compressor which is improved in refueling.

[Prior art]

3 to 5 show a rolling piston type compressor previously proposed by the applicant of the present invention as Japanese Patent Application No. 63-242837. In FIG. 3, 1 is a closed container, 2 is an electric element, 3 is a compression element, and these elements 2 and 3 are accommodated side by side in the closed container 1. The electric element 2 has a stator 2a fixed to the closed casing 1 and a rotor 2b fitted to the stator 2a, and the rotary shaft 4 is fitted and fixed to the rotor 2b. The compression element 3 is configured as follows. That is, the cylinder 5 is provided, and the cylinder 5 and the rotating shaft 4 are coaxially arranged, and the eccentric portion 4a of the rotating shaft 4 is inserted into the cylinder 5. The eccentric portion 4a has a cylindrical rolling piston 6 that eccentrically rotates in the cylinder 5.
Is fitted, both ends of the cylinder 5 are closed by a pair of bearing plates 7a, 7b, the rotary shaft 4 is rotatably supported by the bearing plates 7a, 7b, and the pistons are mounted on the bearing plates 7a, 7b. Both end surfaces of 6 are slidably supported. A vane 8 is supported by the cylinder 5 so as to be movable in the radial direction thereof. The vane 8 is pressed against the outer peripheral surface of the rolling piston 6 by a spring 9 to partition the inside of the cylinder 5 into a low pressure chamber 10 and a high pressure chamber 11. There is. A discharge muffler 12 is fixed to the outer end surface of a bearing plate 7b arranged on the shaft end side of the rotary shaft 4, and a gear pump 13 for oil supply driven by the rotary shaft 4 is provided in the discharge muffler 12. Lubricating oil 14 is stored at the bottom of the closed container 1, an oil suction passage 15 provided in the discharge muffler 12 is opened in the lubricating oil 14, and the oil suction passage 15 is connected to the suction side of the gear pump 13. An oil supply passage 16 is connected to the discharge side of 13. The oil supply passage 16 is formed in series in the discharge muffler 12, the bearing plate 7b, and the rotary shaft 4 and opens to the outer peripheral surface of the rotary shaft 4 so as to supply oil to each bearing portion of the compression element 3.
Further, a groove-shaped oil supply for communicating with the inner side of the rolling piston 6 of the low pressure chamber 10 along the radial direction of the cylinder 5 is provided on the inner surface of the bearing plate 7a which is arranged on the electric element 2 side and fixed to the sealed container 1. A flow path 17 is formed. The rolling piston compressor is a low pressure container type in which the pressure inside the closed container 1 is almost the same as the low pressure side of the compressor. Next, the operation of this rolling piston compressor will be described. When the rotating shaft 4 is driven by the electric element 2, the rolling piston 6 is eccentrically rotated in the cylinder 5, and the vane 8 is constantly in pressure contact with the outer peripheral surface of the rolling piston 6, so that the low pressure chamber 10 is provided in the cylinder 5. And a high-pressure chamber 11 are formed, and the gas introduced into the low-pressure chamber 10 from the suction pipe or the closed container 1 (not shown) is compressed and discharged from the high-pressure chamber 11, passes through the discharge muffler 12, and the discharge pipe (not shown). Is discharged to the high-pressure pipe outside the closed container 1. Further, when the rotary shaft 4 is driven, the gear pump 13 provided at the shaft end portion of the rotary shaft 4 is driven, so that the sealed container 1
Lubricating oil 14 stored at the bottom of the inside is absorbed from the oil suction passage 15 and discharged to the oil supply passage 16, and oil is supplied from the oil supply passage 16 to each bearing portion of the compression element 3. At this time, the pressure inside the rolling piston 6 is almost the same as the pressure inside the sealed container 1 and the low-pressure chamber 10, but the low-pressure chamber 10 changes to 1
Pulsation of about 0.1 to 0.5 kg / cm ² occurs during rotation. Due to this pulsation, when the pressure in the low pressure chamber 10 is lower than the pressure inside the piston 6, lubricating oil flows into the low pressure chamber 10 from the oil supply passage 17 provided in the bearing plate 7a. The lubricating oil that has flowed into the low-pressure chamber 10 is transported in the same manner as gas, and is partially discharged from the high-pressure chamber 11, passes through the discharge muffler 12, passes through the discharge pipe, and flows out to the high-pressure pipe outside the closed container 1. A part of the lubricating oil that has flowed into the low pressure chamber 10 leaks from the inside of the rolling piston 6 and the side surface of the vane 8 into the closed container 1 outside the compression element 3.

[Problems to be Solved by the Invention]

Since the conventional rolling piston type compressor is configured as described above, it is possible to perform proper lubrication in the steady operation state, but when the gas flow rate is high at the time of starting, the inside of the rolling piston and the low pressure chamber There is a problem that a steady differential pressure is generated between them and the flow rate of the lubricating oil to the low pressure chamber increases, and a large amount of the lubricating oil transiently flows out to the high pressure pipe through the discharge port. The present invention has been made to solve the above problems, and a large amount of lubricating oil flows out of the closed container at the time of start-up, so that the lubricating oil in the closed container decreases and insufficient lubrication occurs. To obtain a low-pressure container type rolling piston compressor capable of stably supplying oil to the low-pressure chamber in the cylinder and preventing the heat exchange rate of the heat exchanger from decreasing when used in a refrigeration cycle. Is intended.

[Means for Solving the Problems]

The present invention relates to a rolling piston compressor of a low pressure container type, in which the rolling piston is eccentrically rotated while the rotating shaft makes one rotation on the inner surface of the bearing plate, so that the rolling piston is fully communicated with the low pressure chamber in the cylinder. The oil sump recessed portion is formed in a position and size that are three sections, that is, a section that is closed by the end surface and a section that is in full communication with the inside of the rolling piston.

[Action]

In the rolling piston compressor according to the present invention, the oil sump concave portion is located inside the rolling piston by one rotation of the rotating shaft during operation, and the lubricating oil inside the piston is supplied to the concave portion at the end surface of the piston. Is blocked and the lubricating oil accumulated in the recess remains held in the recess, and the condition where the recess is located outside the piston and the lubricating oil flows out from the recess to the low pressure chamber. Per rotation of the rotating shaft, the amount of lubricating oil proportional to the volume of the recess is supplied to the low pressure chamber regardless of the pressure conditions.
It is possible to always supply a constant amount of lubricating oil to the low-pressure chamber per one rotation of the rotary shaft, and to prevent a large amount of lubricating oil from flowing out of the machine at the time of startup.

【Example】

An embodiment of the present invention will be described below with reference to FIGS. In FIGS. 1 and 2, the same reference numerals as those in FIGS. 3, 4, and 5 indicate the same or corresponding parts, and 18 is an oil formed on the bearing plate 7a and the inner surface in place of the conventional oil supply passage. The oil receiving sump concave portion 18 is a section in which the rolling piston 6 is eccentrically rotated while the rotating shaft 4 makes one revolution and is in a section in which the oil receiving sump concave portion 18 is in full communication with the low pressure chamber 10 in the cylinder 5, that is, on the end surface of the piston 6. The position and size are configured to be a closed section and a section that is in full communication with the inside of the piston 6. Further, the concave portion 18 is a suction port formed in the cylinder 5.
It is located on the vane 8 side rather than 19. The configuration of this embodiment other than that described above is the same as in FIGS. 3, 4, and 5.
This is similar to the conventional low pressure container type rolling piston compressor shown in the figure. Next, the operation of the rolling piston compressor according to this embodiment will be described. When the rotating shaft 4 is driven by the electric element, a gas such as a refrigerant gas is guided to the low-pressure chamber 10 in the cylinder 5 to be compressed and discharged to a high-pressure pipe outside the hermetically sealed container through a discharge pipe (not shown), and The gear pump is driven by the driving of the rotary shaft 4, and the lubricating oil stored in the bottom portion of the closed container is supplied to each bearing portion of the compression element 3 through the oil supply passage 16 in the same manner as the conventional one described above. is there. In this embodiment, one rotation of the rotary shaft 4 causes the rolling piston 6 to roll along the inner wall surface of the cylinder 5, and when the recess 18 is located inside the piston 6, the rolling piston 6 is moved to the recess 18. The lubricating oil inside the piston 6 is supplied. The lubricating oil is introduced to the inside of the piston 6 through the oil supply passage 16. Next, in the section where the recess 18 is closed by the end face of the piston 6, the lubricating oil accumulated in the recess 18 is retained in the recess 18 as it is. Furthermore, when the recess 18 is in full communication with the low pressure chamber 10, the lubricating oil in the recess 18 is affected by the action of the suction gas flow,
It flows into the low pressure chamber 10. As a result, the recess 18 that has released the lubricating oil is closed again by the piston 6. afterwards,
Returning to the initial state described above, the recess 18 is in full communication with the inside of the piston 6. Therefore, the lubricating oil having an oil amount proportional to the volume of the recess 18 per one rotation of the rotary shaft 4 by the operation of the compressor is supplied to the low pressure chamber 10 regardless of the pressure condition, and stable oil supply can be realized. In addition, the suction port 19 of the cylinder 5
Since the concave portion 18 is provided closer to the vane 8 side than that, the supply of the lubricating oil to the vane 8 is improved, and the wear resistance is excellent. In the above embodiment, the bearing plate 7a on the electric element side of the rotating shaft 4 is provided.
Although the recess 18 is provided on the shaft end, the present invention may provide the shaft end side bearing plate 7b with a recess, or both the bearing plates 7a, 7b may be provided with a recess, and the pump for supplying the lubricating oil may be a pump other than the gear pump. It may be a pump.

【The invention's effect】

As described above, according to the present invention, the inner surface of the bearing plate that closes the end surface of the cylinder is fully communicated with the low pressure chamber in the cylinder by the eccentric rotation of the rolling piston during one rotation of the rotating shaft, By forming the oil-storing concave portion that is a section that is closed by the end surface of the piston and a section that is in full communication with the inside of the piston, a fixed amount proportional to the volume of the concave section per rotation of the rotating shaft is formed. Lubricating oil can be stably supplied to the low-pressure chamber regardless of operating pressure conditions, and therefore, it is possible to prevent multiple lubricating oil from flowing out of the machine at the time of startup, etc., and prevent insufficient supply of lubricating oil. Moreover, when used in a refrigeration cycle, there is an effect that a low-pressure container type rolling piston compressor can be obtained which can prevent the heat exchange rate of the heat exchanger from decreasing.

[Brief description of drawings]

1 is a cross-sectional view showing a compression element of a rolling piston compressor according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of FIG.
II-II sectional view, FIG. 3 is a longitudinal sectional view showing a main part of a conventional rolling piston compressor, FIG. 4 is a transverse sectional view of the same compression element, and FIG. 5 is VV of FIG. It is a line sectional view. 1 ... airtight container, 2 ... electric element, 3 ... compression element, 4
…… Rotary shaft, 5 …… Cylinder, 6 …… Rolling piston, 7a, 7b …… Bearing plate, 8 …… Vane, 10 …… Low pressure chamber, 1
3 ... Pump, 14 ... Lubricating oil, 16 ... Oil supply passage, 18 ... Oil reservoir recess, 19 ... Suction port. The same reference numerals in the drawings indicate the same or corresponding parts.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Tatsuya Sugita Inventor Tatsuya Sugita 3-18-1, Oshika, Shizuoka-shi, Shizuoka Mitsubishi Electric Corporation Shizuoka Works (56) Reference JP-A-63-50696 (JP, A) Actual Kaisho 61-57187 (JP, U)

Claims (1)

[Claims] 1. A rotating shaft driven by an electric element, a rolling piston fitted to an eccentric portion provided on the rotating shaft and rolling along an inner wall surface of a cylinder, and contacting an outer peripheral surface of the piston. Has a vane for partitioning the interior of the cylinder into a high pressure chamber and a low pressure chamber, and a pair of bearing plates for closing both end surfaces of the cylinder. The above parts are housed in a closed container in which lubricating oil is stored at the inner bottom. In a low-pressure container type rolling piston compressor in which this closed container has a pressure almost the same as the low-pressure side of the compressor, an oil sump recess is formed on the inner surface of the bearing, and the rotary shaft makes one revolution in the recess. In the meantime, due to the eccentric rotation of the rolling piston, a section that completely communicates with the low-pressure chamber in the cylinder, a section that is closed by the end surface of the rolling piston, and completely communicates with the inside of the rolling piston. Rolling piston type compressor, characterized in that the position and size to be between the three sections.