JPH0245679A - Rotary compressor - Google Patents

Abstract

PURPOSE:To prevent insufficiency of lubrication by providing the first communication path intermittently connecting a back pressure chamber to communicate with a suction chamber and the second communication path intermittently connecting the back pressure chamber to communicate with lubricating oil in the bottom part of a closed casing. CONSTITUTION:The first communication path 21, intermittently connecting a back pressure chamber 22 to communicate with a suction chamber 11a or a suction passage 15 or a suction pipe, and the second communication path 24, intermittently connecting the back pressure chamber 22 to communicate with lubricating oil in the bottom part of a closed casing 1, are provided. By intermittently opening and closing the first and second communication paths 21, 24, a pressure in the back pressure chamber 22 is held to an intermediate pressure approximate to a limit pressure at which a vane 20 comes into contact with a roller 5, and a sliding loss is reduced. In this way, a flow of the lubricating oil to the suction chamber 11a or the like is formed through the back pressure chamber 22 from the bottom part of the closed casing 1 surely one time per one turn of a shaft 3.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a rotary compressor used in a refrigeration cycle or the like, and particularly relates to a configuration with little sliding loss.

Conventional technology Conventional (t6 configurations are shown in Fig. 7, Fig. 8, Fig. 9, Fig. 10,
This will be explained using FIG. 11.

1 is a sealed casing, 2 is an electric motor section, and shaft 3
Through the cylinder 4, roller 5, vane 6, main bearing,
It is connected to a mechanical part main body 9 constituted by a sub-bearing 8. The shaft 3 consists of a main shaft 3a, a sub-shaft 3b, and a crank 3C. 10 is a spring provided on the back side of the vane. 11a and 11b are the rollers 5 and the base 7 in the cylinder 4.
6. A suction chamber and a compression chamber constituted by a main bearing 7 and a sub-bearing 8. 12 is an oil supply mechanism connected to the shaft 3. Reference numeral 13 denotes a back pressure chamber constituted by the rear surface of the vane e on the opposite side to the contact surface with the roller 5, the cylinder 4, the main bearing 7, and the sub-bearing 8. The main bearing 7 also has a first oil passage 7a.
and a third oil passage 7b are provided, and the bay 76 is also provided with a second oil passage 6a. These oil passage elements a and 7b.

6b, the vane 6 is rotated at the crank rotation angle θ as shown in FIG.
-〇2π When the vane 6 is near the top dead center A, everything is in communication, and as shown in Fig. 8 and Fig. 1o, when the vane 6 is near the bottom dead center B of the crank rotation angle θ=π. The holes are made so that they are not all connected.

Reference numeral 14 denotes a suction pipe, which communicates with the suction chamber 11a via the auxiliary bearing 8 and the suction passage 15 of the cylinder 4. Reference numeral 16 denotes a discharge section, which is connected to the sealed casing 1 through a discharge valve (not shown).
It communicates with the inside. The numeral 1 is a discharge pipe and opens into the sealed casing 1.

18 is a lubricating oil into which refrigerant is partially dissolved.

Next, the compression mechanism of the rotary compressor will be explained.

Refrigerant gas from the cooling system (not shown) is supplied to the suction pipe 14.
, a suction chamber 11a inside the cylinder 4 guided from the suction passage 15
leading to. The refrigerant gas that has reached the suction chamber 11a is transferred to the shaft 3
The compression chamber 11b is partitioned by a roller 5 and a vane 6, which are rotatably housed in a crank 3c.

The compressed refrigerant gas is once discharged into the sealed casing 1 via the discharge section 16 and the discharge valve, and then discharged to the cooling system via the discharge pipe 17.

Next, the flow of lubricating oil in which some refrigerant is partially dissolved will be explained. After the lubricating oil 18 is sent to the sliding parts between the shaft 3, the main bearing 7, the auxiliary bearing 8, and the rollers 5 via the oil supply mechanism, a portion of the lubricating oil 18 directly returns to the lower part of the sealed casing 1 and a portion of the lubricating oil 18 enters the compression chamber 11b. The gas enters the air, is discharged together with the refrigerant gas, and returns to the lower part of the sealed casing 1.

Regarding the space between the vane 76 and the cylinder 4, when the vane 6 reaches the top dead center, the lubricating oil 18 at the bottom of the sealed casing 1 and the back pressure chamber 13 communicate with each other via the oil passages 7a, 7b, and 7c to form a back pressure chamber. High pressure lubricating oil 18 flows into 13. While the vane 6 slides back and forth, leakage leaks into the suction chamber 11a and the compression chamber 11b, lubricating and sealing the space between the vane 6 and the cylinder 4.

By the way, after inhaling high pressure lubricating oil near top dead center A,
While the vane 6 moves from the top dead center A to the bottom dead center B, the back pressure chamber B does not communicate with the lubricating oil 18 at the bottom of the sealed casing 1, and the volume of the back pressure chamber 13 increases. The pressure decreases and becomes an intermediate pressure PM between the high pressure Pd and the resistance pressure P,
Next, while moving from bottom dead center B to top dead center A, there is no communication with lubricating oil 18 and the volume of back pressure chamber 13 decreases, so back pressure chamber 1
The pressure at step 3 rises again and becomes high pressure.

Therefore, the pressure in the back pressure chamber 13 fluctuates between the high pressure Pd and the intermediate pressure PM, but since it is higher than the limit pressure PC at which the vane 6 and the roller 5 separate, when the back pressure of the vane 6 is always set to the high pressure Pd. Compared to the above, the contact load between the vane 6 and the roller 5 was reduced, the sliding loss was reduced, and the reliability was improved.

For example, it is shown in Japanese Patent Application Laid-Open No. 61-106992.

Problems to be Solved by the Invention In such a conventional configuration, - once the lubricating oil has flowed into the back pressure chamber, a portion of it flows out into the suction chamber and compression chamber through the gap between the vane and the cylinder; This amount is very small because the back pressure chamber is small, and the pressure in the back pressure chamber becomes high pressure at top dead center, so even if the back pressure chamber and the lubricating oil section communicate, almost no lubricating oil is replenished. become. Therefore, there is almost no lubricating oil going in and out 9 in the back pressure chamber, and the same lubricating oil always exists, which causes the temperature of the lubricating oil to rise, the temperature of the sliding parts of the vane and cylinder to rise, and the viscosity to decrease. In addition to problems such as poor lubrication, there were problems in terms of reliability as wear particles accumulated in the back pressure chamber, which could cause seizure. In addition, in specifications such as small eccentricity, the volumetric increase of the back pressure chamber at the top dead center and bottom dead center positions is small, and the intermediate pressure PM is P.

There was a problem that I couldn't complete until I got close to . The present invention solves the drawbacks of the conventional example described above, and reduces the pressure in the back pressure chamber to P.
The objective is to improve reliability and performance by setting an intermediate pressure close to c and increasing the amount of lubricating oil flowing through the back pressure chamber within a range that does not cause performance deterioration.

Means for Solving the Problems The present invention provides a first communication path that intermittently communicates between the back pressure chamber and the suction chamber or the suction passage, the suction pipe, etc.; The second communication passage is provided with a second communication passage that communicates with the other parts.

Function: With the above-described configuration, the pressure in the back pressure chamber decreases when the back pressure chamber communicates with the concave pressure side of the suction chamber, and when the back pressure chamber communicates with the lubricating oil in the lower part of the sealed casing. Taking advantage of the increase in pressure, by intermittently opening and closing the first and second communication passages, the pressure in the back pressure chamber is maintained at an intermediate pressure close to the limit pressure at which the vane and roller come into contact, and the sliding In addition to reducing dynamic losses, lubricating oil flows from the bottom of the sealed casing to the suction chamber, etc. through the back pressure chamber at least once per rotation of the shaft, so the lubricating oil in the back pressure chamber is constantly replaced. Therefore, reliability can be improved.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 to 6. Note that the same parts as in the conventional example are given the same reference numerals and detailed explanations are omitted.

19 is a cylinder, 20 is a vane, and a notch 19a provided in a portion of the cylinder 2o that accommodates the bay 720 and a notch 20a provided in the bay 720 constitute a first communication path 21.

The first communication path 21 is connected to the back pressure chamber 22 when the notch 19a and the notch 20a overlap due to the reciprocating movement of the vane 20.
and communicates with the suction chamber 11a. Further, 23 is a main bearing, and a second communication passage 24 is opened in the main bearing 23.
The reciprocating movement of the vane 20 causes the lubricating oil section 18 in the lower part of the closed casing 1 to communicate with the back pressure chamber 22 intermittently. Also, the first communication path 21 connects the back pressure chamber 22 and the suction chamber 11a.
The time ΔT1 during which the lower part of the sealed casing 1 and the back pressure chamber 22 communicate through the second communication path 24 is set longer than the time ΔT2 during which the lower part of the sealed casing 1 and the back pressure chamber 22 communicate with each other.

As in the past, refrigerant gas flows through the suction pipe 14 and the suction passage 16.
After being sucked into the suction chamber 11a through the suction chamber 11a and compressed in the compression chamber 11b, it is discharged through the discharge section 16, the sealed casing 1, and the discharge pipe 17.

At this time, the back pressure chamber 22 is connected to the suction chamber 11a and the first communication path 2.
1 and intermittently communicate with the lubricating oil of the sealed casing 1 through the second communication path 24, but the communication time with the first communication path 21 is long. Therefore, back pressure chamber 2
In No. 2, the first communication path opens immediately before the second communication path 24 opens and the pressure decreases, so the inflow amount of lubricating oil can be increased, and the second communication path 24 Since the first communication path continues to listen for a while even after closing, it is possible to prevent the pressure in the back pressure chamber 22 from increasing excessively.

From the above, the pressure in the back pressure chamber 22 is
P, which is the critical pressure at which . The pressure can be controlled between PM1 and PM2 as close as possible to , the contact load between the roller 5 and the vane 20 is reduced, and the sliding loss is lower than before. Furthermore, once per rotation of the shaft 3, a flow of lubricating oil is formed from the lower part of the sealed casing 1 via the back pressure chamber 22 to the suction chamber 11a, so the lubricating oil in the back pressure chamber is constantly replaced and the temperature Poor lubrication due to rising can be prevented, and seizure due to accumulation of wear particles can also be prevented.

In this embodiment, the first communication passage and the second communication passage communicate with the back pressure chamber in the vicinity of the bottom dead center B. Needless to say, it is okay to communicate with the room. That is, the two communication passages communicate with the back pressure chamber, so that the pressure in the back pressure chamber becomes P. Needless to say, it is sufficient as long as the pressure is controlled to an intermediate pressure close to . For example, as shown in FIG. 6, the cylinder 26 is provided with two notches 25a and 25b, the vane 26 is provided with a notch 26a, and these three notches 25
It goes without saying that the back pressure chamber 27 and the suction chamber 11a may be communicated with each other at a position approximately midway between the top dead center A and the bottom dead center B by means of a, 25b, and 26a.

Further, in this embodiment, the case where the back pressure chamber and the suction chamber are communicated has been described, but it goes without saying that the back pressure chamber may be communicated with the suction passage or the suction pipe.

Effects of the Invention As is clear from the above description, the present invention includes a sealed casing, a cylinder housed in the sealed casing, a main bearing and a sub bearing fixed to both ends of the cylinder, and a main bearing and a sub bearing fixed to both ends of the cylinder. A shaft that is rotatably housed and has a crank, a roller that is fitted into the crank of the shaft and rotates inside the cylinder, and the inside of the cylinder is divided into a suction chamber and a compression chamber by reciprocating in the groove of the cylinder and coming into contact with the roller. a suction passage and suction pipe communicating with the suction chamber; a back pressure chamber surrounded by the back of the vane, the cylinder, the main bearing, and the sub bearing; and the back pressure chamber and the suction chamber or the suction passage or the suction pipe. Since it is equipped with a first communication passage that communicates intermittently and a second communication passage that communicates intermittently between the back pressure chamber and the lubricating oil at the bottom of the sealed casing, sliding loss is reduced. Since problems such as poor lubrication and seizure are reduced, it is possible to provide compressors with high efficiency and reliability.

[Brief explanation of the drawing]

FIG. 1 is a sectional view at the top dead center of the back pressure chamber of a rotary compressor showing an embodiment of the present invention, and FIG. 2 is a sectional view at the dead center of the back pressure chamber of the same embodiment. Fig. 3 is a front view of the cylinder part in Fig. 1 at the top dead center, Fig. 4 is a front view of the cylinder part in Fig. 2 at the dead center, and Fig. 5 is the communication path of the embodiment shown in Fig. 1. Fig. 6 is a front view of a cylinder section showing another embodiment of the present invention, Fig. 7 is a vertical cross-sectional view of a conventional rotary compressor, Fig. 8 The figure is Ix −Ji in Figure 7
[An arrow view along the x/ line, FIG. 9 is a sectional view of the conventional back pressure chamber at the top dead center, FIG. 10 is a sectional view of the conventional back pressure chamber at the bottom dead center, FIG. 11 1 is a diagram of a conventional opening/closing situation of an oil passage and a diagram of a change curve of back pressure chamber pressure. 1... Sealed casing, 3... Shaft, 3c... Crank, 6... Roller, 8... Sub-bearing, 11a... ...inhalation chamber,
111)...Compression chamber, 14...Suction pipe, 16...Suction passage, 19, 25...
・Cylinder, 20.26... Vane, 21...
...First communication path, 22.27...Back pressure chamber, 23...Main bearing, 24...Second communication path. Name of agent: Patent attorney Shigetaka Awano et al. 16th
1 Figure 1 - Meiken casing 3 - Shift 30° - Crank 5 - Roller 8 - Akira +7 yen! IE receiver I9- crank z0゛-vane zf-・yi f speed 1 path zf,-? Zhou z3 - Lord lees receiver? 4゛・'Second communication passageway 3 Fig. M4 Fig. 2 Fig. Fig. Fig. Fig. 0 Fig. Fig. 1 Fig. 1 Fig. 2 B)

Claims (1)

[Claims] A sealed casing, a cylinder housed in the sealed casing, a main bearing and a sub-bearing fixed to both ends of the cylinder, a shaft rotatably housed in the main bearing and sub-bearing and having a crank, and the shaft. a roller that is fitted in a crank and rotates eccentrically within the cylinder; a vane that reciprocates within a groove of the cylinder and comes into contact with the roller to divide the inside of the cylinder into a suction chamber and a compression chamber; A suction passage and a suction pipe that communicate with each other;
a back pressure chamber surrounded by the back surface of the vane, the cylinder, the main bearing, and the auxiliary bearing; a first communication path that intermittently communicates the back pressure chamber with a suction chamber, a suction passage, or a suction pipe; , a rotary compressor comprising a second communication path that intermittently communicates between the back pressure chamber and the lubricating oil in the lower part of the sealed casing.