JPH0367090A - Rotary compressor - Google Patents

Abstract

PURPOSE:To prevent reduction in an achievement coefficient during operation and to obtain a good pressure balance during a shutdown by providing a balance groove on an end surface of a cylinder block, by forming a muffler chamber and an oil reserving chamber, and by making an opening end of the oil reserving chamber faced by the balance groove. CONSTITUTION:A lubricant supplied from an oil pump during operation flows out of the tip end of a bearing 6 through an interval between a shaft 4 and a main bearing 6 and is guided to an oil reserving chamber 16, and the lubricant which has been collected is guided by a balance groove 12 and fills it. Thus, refrigerant gas is prevented from flowing into a cylinder chamber 5a through the balance groove 12, which prevents reduction in an achievement coefficient during operation. Also, during a shutdown, as there is no oil supplied form the oil pump, the lubricant which has been collected in the balance groove 12 flows down along it, and high pressure refrigerant gas can be guided into the cylinder chamber 5a from the balance groove 12, which achieves a good balance between the high pressure side and the low pressure side.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a rotary compressor that is incorporated into a refrigerator, an air conditioner, etc. This invention relates to a rotary compressor that reduces the startup load when restarting by achieving a pressure balance between the high pressure side and the low pressure side.

(Prior art) Conventionally, in a rotary compressor, the main bearing and sub-bearing arranged on both open end sides of the cylinder block and the clearance between the roller end face, etc.
It has been common practice to balance the pressure between the high pressure side and the low pressure side inside the cylinder chamber when the engine is stopped, thereby reducing the starting load when restarting the engine.

Here, in order to improve the pressure balance characteristics, it is necessary to increase the clearance to some extent, but if it is increased, a large amount of refrigerant gas on the high pressure side will leak to the low pressure side during operation, leading to a decrease in compression efficiency. I end up. On the other hand, if the pressure saw is made smaller, the balance characteristics of the pressure saw when the operation is stopped deteriorates, and there is a problem that it becomes impossible to maintain a sufficient pressure balance between the high-pressure side and the low-pressure side.

Furthermore, as shown in Utility Model Application No. 51-124905, etc., it is generally known to use a pressure regulating device to maintain pressure balance when the operation is stopped, but the structure is complicated and the cost is high. There was a problem that increased significantly.

Therefore, the applicant aims to balance the pressure between the high-pressure side and the low-pressure side inside the cylinder chamber at the time of shutdown, and reduce the startup load at the time of restart, without causing a decrease in compression efficiency or using a complicated pressure adjustment device. In order to reduce the
No. 38883 (Utility Application No. 61-26505) was proposed.

This will be explained with reference to FIGS. 6 and 7.

That is, a compression element 2 and an electric element 3 are housed in a sealed case 1, connected to each other via a shaft 4. This compression element 2 includes a cylinder block 5 having a cylinder chamber 5a, a main bearing 6 and a sub-bearing 7 arranged at both open ends of this block 5, and this cylinder chamber 5a.
a roller 8 located inside and eccentrically fitted to the shaft 3; a blade 9 that partitions the cylinder chamber 5a into a high pressure chamber 5b side and a low pressure chamber 5C side;
It mainly consists of a compression spring 10 that urges the roller 8 toward the roller 8 side. The blade 9 is positioned within a blade groove 11 provided in the cylinder block 5, and one end of the blade 9 is placed on the end surface of the cylinder block 5 so that the blade 9 slides between the side wall of the blade groove 11 on the low pressure chamber side. A balance groove 12 is provided which opens facing the dynamic clearance and whose other end opens in a space inside the sealed case 1. This results in
When the operation is stopped, the high pressure refrigerant gas in the sealed case 1 is caused to flow from the balance groove 12 into the low pressure chamber 5b side of the cylinder chamber 5 through the clearance between the side surface of the blade groove 11 on the low ratio chamber side and the side surface of the blade. This is designed to balance the pressure between the high pressure side and the low pressure side.

(Problems to be Solved by the Invention) However, although the device described in Utility Model Application No. 138883/1983 achieves the original purpose, even during operation, refrigerant gas flows into the cylinder through the balance groove. As a result, the coefficient of performance of the compressor deteriorates. In order to affix this, the cross-sectional area of the balance groove is reduced to reduce the amount of refrigerant gas flowing into the cylinder, but it is necessary to maintain a sufficient pressure balance between the high-pressure side and low-pressure side of the west side of the cylinder chamber when the operation is stopped. It was found that there were problems such as not being able to achieve the desired results.

In view of the above, the present invention further improves on Utility Model Application Publication No. 138883/1983 to achieve a pressure balance between the high pressure side and the low pressure side when the operation is stopped, and also to solve the problem that the coefficient of performance deteriorates even during the operation. The aim is to provide what is not available.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the rotary compressor according to the present invention has a balance groove that communicates with the inside of the cylinder chamber on the end face of the cylinder block, and a bearing disposed on the end face of the cylinder block. The entire flange portion is surrounded by a first stage valve cover to form a muffler chamber, and the second stage 11 valve covers are surrounded from this first stage valve cover to the outside of the tip of the bearing to form an oil reservoir chamber. Furthermore, the oil reservoir chamber is partially opened, and this open end faces the balance groove.
High-pressure refrigerant gas is guided into the cylinder chamber through the balance groove to balance the pressure between the high-pressure side and the low-pressure side. During operation, lubricating oil flows out from the tip of the bearing through the gap between the shaft and the bearing. The refrigerant gas is guided into the oil sump chamber, and the lubricating oil once collected here is guided to the balance groove to fill it, thereby reliably preventing the refrigerant gas from flowing into the cylinder chamber through the balance groove. can.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the main parts of a first embodiment applied to a vertical compressor.A balance groove 12 having a structure similar to that of the conventional example described above is provided on the end face of the cylinder block 5. A main bearing 6 is disposed on the end face of the main bearing 6, which closes the end face and supports the shaft 4 at the same time.

The entire flange portion of this main bearing 6 is surrounded by the first-stage valve cover 13, so that this first-stage valve cover 13
A sealed muffler chamber 14 is formed between the valve cover 13 of the third stage and the main bearing 6.

Further, a second stage valve cover 15 whose lower end is joined to the periphery of the first stage valve cover 13, extends further upward, and whose upper end reaches the tip of the main bearing 6 to seal it there is a second stage valve cover 15. The second valve cover 15 and the first valve cover 1
3, an oil reservoir chamber 16 is formed which is sealed and enclosed. Thereby, the lubricating oil that has flowed from the inside of the cylinder chamber 5a to the outside through the gap between the shaft 4 and the main bearing 6 is temporarily stored in the oil reservoir chamber 16.

Further, a flow passage 17 communicating with the oil reservoir chamber 16 is formed between the first stage valve cover 13 and the second stage valve cover 15, and the lower open end 17a of the flow passage 17 is It faces the upper surface of the balance groove 12.

As a result, lubricating oil supplied from an oil pump (not shown) during operation flows out from the tip of the bearing 6 through the gap between the shaft 4 and the main bearing 6 and is guided to the oil reservoir chamber 16. During operation, the lubricating oil that once accumulated here is guided to the balance groove 12 and fills it, thereby reliably preventing the refrigerant gas from flowing into the cylinder chamber 5a through the balance groove 12. Prevent a decline in the coefficient of performance. In addition, when the operation is stopped, there is no oil supply from the oil pump, so the lubricating oil that has accumulated inside the balance groove 12 flows down along this flow, so that the lubricant oil does not accumulate in the balance groove 12. This allows high pressure refrigerant gas to flow from the balance groove 12 into the cylinder chamber 5.
It is possible to balance the pressure between the high pressure side and the low pressure side by introducing the pressure into the inside of a.

In addition, a refrigerant vent hole 18 is formed at the joint between the first and second stage valve covers 13 and 15, allowing the refrigerant gas inside the cylinder chamber 5a to pass through the inside of the main bearing 6 and drain the muffler. The refrigerant enters the chamber 14 and further flows out 1° from the refrigerant vent hole 18 to the outside to exhibit a silencing effect.

FIG. 2 shows a second embodiment applied to a vertical compressor, and the difference from the first embodiment is that the flow path 17
Instead of providing a hole, a hole is formed in the second stage valve cover 15 that partitions the oil reservoir chamber 16, and the other end of a pipe connected to this hole faces the upper surface of the balance groove 12. The lubricating oil once stored in the oil reservoir chamber 16 during operation is guided into the balance groove 12 through one pipe.

FIG. 3 shows a first embodiment applied to a horizontal compressor, in which the main bearing 6 is surrounded by a first stage valve cover 13 and the entire area of the first stage valve cover 13. The valve cover 15 is doubly surrounded by a second stage valve cover 15 reaching the tip of the valve cover 6, and a muffler chamber 14 is formed on the inside, and an oil reservoir chamber 16 is sealed on the outside. Further, a through hole 6a is formed in the main bearing 6 at a position corresponding to the balance groove 12, and a hole 13a is also formed in the first stage valve cover 13 corresponding to the through hole 6a. ing. Furthermore, an overflow hole 15a for overflowing lubricating oil is provided at a predetermined height position of the second stage valve cover 15.

As a result, lubricating oil supplied from an oil pump (not shown) during operation flows out from the tip of the bearing 6 through the gap between the shaft 4 and the main bearing 6 and is guided to the oil reservoir chamber 16. The lubricating oil 16 that collects at the bottom of the lever passes through the perforation 13a of the first stage valve cover 13 and the through hole 6a of the main bearing 6, and is led to the balance groove 12, filling it. It reliably prevents refrigerant gas from flowing into the cylinder chamber a through the groove 12, and when the operation is stopped, there is no oil supply from the oil pump, so high-pressure refrigerant gas flows through the balance groove 12 into the cylinder chamber. 5a to balance the pressure between the high pressure side and the low pressure side.

Figures 4 and 5 show a second embodiment applied to a horizontal compressor, and the differences from the first embodiment are as follows.
Instead of providing a through hole 6a in the main bearing 6 or a perforation 13a in the first stage valve cover 13, the main bearing 6 having a flange portion with a slightly smaller diameter than the outer diameter of the cylinder block 5 is used, and the second stage valve cover 13 is not provided with a through hole 6a. Valve cover 15
is brought into close contact with the outer circumferential surface of this flange portion, and a bulge 15b protruding outward in a semicircular shape is formed at a position corresponding to the balance groove 12, and the inside thereof is used as a flow path, whereby the oil reservoir chamber 16 The lubricating oil accumulated therein is guided to the balance groove 12 by passing through this bulge (flow path) 15b.

〔Effect of the invention〕

Since the present invention has the above-described configuration, lubricating oil supplied from the oil pump during operation comes out from the tip of the bearing and is temporarily stored in the oil reservoir chamber, and then guided into the balance groove, thereby Lubricating oil accumulates in the balance groove, which improves the sealing performance of the balance groove and prevents a decrease in the coefficient of performance during operation. Furthermore, while the operation is stopped, the lubricating oil in the balance groove can be removed to quickly balance the pressure.

Furthermore, there is an effect that the lubricating oil discharged from the bearing and the refrigerant gas are prevented from mixing, and the amount of discharge from the compressor case can be significantly reduced.

[Brief explanation of drawings]

Figures 1 and 2 are joint sectional views showing the main parts of embodiments applied to different vertical rotary compressors, Figure 3 is a joint sectional view showing the main parts of an embodiment applied to a horizontal rotary compressor, and Figure 4 The figure is a diagram equivalent to Figure 3 (Figure 5) showing another embodiment.
Figure 5 is a joint cross-sectional view of the bearing part in Figure 4, Figures 6 and 7 are conventional examples,
Figure 6 is a longitudinal cross-sectional view, and Figure 7 is the sixth figure with the sealed case omitted.
It is a sectional view taken along the line ■-■ in the figure. 4...Shaft, 5...Cylinder block, 5a.
...Cylinder chamber, 61.・Main bearing, 9...
Blade, 11...Blade groove, 12...Balance groove, 13...1st stage valve cover, 14...Muffler chamber, 15...2nd stage valve cover, 16.../
11] Reservoir. Figure 6

Claims (1)

[Claims] A balance groove leading to the inside of the cylinder chamber is provided on the end face of the cylinder block, and the entire flange portion of the bearing placed on the end face of the cylinder block is surrounded by a first stage valve cover to cover the muffler chamber and the first stage valve. An oil reservoir chamber is formed by surrounding the cover with a second stage valve cover from the cover to the outside of the tip of the bearing, and furthermore, the oil reservoir chamber is partially opened, and this open end faces the balance groove. A rotary compressor characterized by: