JPS62131992A - Rotary compressor - Google Patents

Abstract

PURPOSE:To improve the intake efficiency of a rotary compressor, by decreasing the pressure of the low pressure side of a cylinder chamber with the operation of the compressor, moving a check valve to a valve receiving side space, opening an inlet, absorbing gas from a cooler into the cylinder chamber, and opening the check valve widely. CONSTITUTION:When a compressor is started to operate, the capacity of the inlet side 10a of a cylinder chamber 10 is enlarged corresponding to the rotation of a rolling piston 11, and its internal pressure is decreased. Then, the pressure of valve receiving side space 21b of an intake passage 21 which is communicated with the cylinder chamber inlet side 10a via an equalizing passage 25 is also decreased, and differential pressure between the pressure inside an intake pipe 12 and the pressure thereof is generated by a check valve 23 intervened. When this differential pressure becomes bigger than the force of the compression coil spring 24 of the check valve 23, the valve 23 is pressed back into the valve receiving space 21b, and an inlet 12a is opened. Thus, refrigerant gas from a cooler is absorbed into the cylinder chamber 10 so as to work in the direction for opening widely the check valve 23. Therefore, sufficient flow area is assured for an inlet side space 21a, so that the intake efficiency of the compressor is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a rotary compressor that can improve the operating efficiency of a refrigeration system.

[Conventional technology]

4 and 5 are sectional views showing a conventional rotary compressor disclosed in, for example, Japanese Utility Model Application Publication No. 58-87988. In the figures, 1 is a closed case, a stator 2 and a rotor 3. The motor-driven element 4 and the compression element 6 connected to the rotor 3 via the rotating shaft 5 are built in. The compression element 6 includes a cylinder chamber 1 which is fixed to cover openings at both ends of the cylinder 7 and is surrounded by a frame 8 and a head 9 that support the rotating shaft 5.
0, and a rolling piston 11 eccentrically fitted onto the rotating shaft 5 is housed in the cylinder chamber 10. 12 has one end fixed to the head 9, and the sealed case 1
This is a suction pipe that penetrates through and communicates with a cooler (not shown).

A check valve 13 opens and closes the suction port 12a, which is the outlet of the suction pipe 12, and is constructed as a reed valve (tongue-shaped valve) with one end of an elastic metal plate fixed to the head 9 with a bolt 14. Reference numeral 15 indicates a suction passage that communicates the intake port 12a having the check valve 13 with the low pressure side of the cylinder chamber 10, and reference numeral 16 indicates a stopper that protrudes into the suction passage 15 and regulates the opening limit of the check valve 13. Department.

Note that 8a is an oil groove provided in the frame 8, which supplies lubricating oil 1a stored at the bottom of the sealed case 1 to the rotating shaft 5.

Next, the operation will be explained.

The above-mentioned rotary compressor is connected to a cooling system of a refrigerator, for example.

When the electric element 4 is energized and the compressor is operated, the rotor 3
rotates, and the rotation is transmitted through the crankshaft 5 to the compression element 6
This is transmitted to the rolling piston 11 that constitutes the cylinder 7, and the cycle of sucking, compressing, and discharging the refrigerant inside the cylinder 7 is repeated. rolling piston 11
The pressure in the suction passage 16 becomes low as the volume of the cylinder chamber 10 changes as the cylinder rotates, and the check valve 13 repeats opening and closing in balance with the pressure of refrigerant gas from a cooler (not shown).

When the compressor stops, the check valve 13 closes the suction port 12a with its own elastic restoring force. Shortly after this stop, the compressed refrigerant gas remaining on the high pressure side of the cylinder chamber 10 passes through the minute gaps between the assembled parts of the cylinder 7, frame 8, head 9, and rolling piston 11.
It flows back into the suction passage 16 from the low pressure side of the cylinder chamber 10.

The check valve 13 is already closed at that time and blocks the superheated refrigerant gas flowing back. This prevents the superheated gas from flowing into the cooler (not shown) through the suction pipe 12 and increasing the temperature inside the cooler.

[Problem that the invention seeks to solve]

However, in the conventional rotary compressor, since the check valve 13 is configured as a reed valve, the lift amount h (see Fig. 5) in the open state is not sufficient, and the suction gas passage is will be narrowed down. Therefore, there is a problem in that the flow resistance of the suction gas in the compression element during compressor operation becomes large, reducing the gas suction efficiency of the compressor and unnecessarily increasing the energy consumption of the refrigeration system.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to obtain a rotary compressor having a reversal function in which the suction efficiency of refrigerant gas is hardly reduced.

[Means for solving problems]

The rotary compressor according to the present invention has a cylindrical suction passage provided in the cylinder adjacent to the cylinder chamber and communicating between the lower (E side) of the cylinder chamber and the compressor suction port. A check valve having an outer diameter slightly smaller than the inner diameter of the suction passage is slidably inserted in the axial direction.

The check valve partitions the suction passage into a suction side space and a valve housing space, and the valve housing space and the low pressure side space of the cylinder chamber are connected via a pressure equalization passage.

[For production]

When the pressure on the low pressure side of the cylinder chamber decreases due to operation of the compressor, the pressure of the refrigerant gas sucked from the cooler becomes higher, and the reverse pressure valve in this invention is pushed open due to the pressure difference. The valve body then largely slides within the suction passage and retreats to the valve storage space. Therefore, the space on the gas suction side of the suction passage becomes a wide space, and the refrigerant gas sucked from the suction pipe passes through the passage without being restricted, and is therefore sucked in extremely efficiently.

When the compressor stops, the low-pressure side space of the cylinder chamber and the valve storage side space and suction side space of the suction path are immediately equalized by the action of the pressure equalization path, so the check valve (due to spring force or self-weight) Move) g! Close the entrance.

Subsequently, superheated refrigerant gas leaking from the high pressure side in the cylinder chamber is blocked by this check valve, so that a temperature rise due to backflow of superheated gas to the cooler is prevented.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
3, reference numerals 1 to 12 are the same as those in FIGS. 4 and 5, and detailed explanation will be omitted.

In the figure, 21 is a cylindrical suction passage that passes through the body of the cylinder 7 in the axial direction, and the suction port 12a of the suction pipe 12 is located at one end of the passage, and the opposite end is closed by the frame 8. It is provided. 22 is a suction groove that communicates this suction passage 21 with the low pressure side of the cylinder chamber 10. Reference numeral 23 denotes a back pressure valve, which has an outer diameter slightly smaller than the inner diameter of the suction passage 21 and is formed in a cylindrical shape shorter than the overall length of the suction passage 21, and is slidable in the axial direction within the suction passage 21. It has been inserted. Reference numeral 24 denotes a compressed fill spring built into the check valve 23 that constantly biases the check valve 23 toward the suction port 12a, but the biasing force is somewhat greater than the sliding resistance of the check valve 23. A large amount is fine. The suction passage 21 is partitioned by the inserted check valve 23 into a suction side space 21a serving as a passage for suction gas and a valve housing side space 21b housing the check valve 23 in an open state. Reference numeral 25 denotes a pressure equalizing passage that communicates the valve housing side space 21b of the suction passage 21 with the low pressure side of the cylinder chamber 10, and is formed in the frame 8. Reference numeral 26 is a slide valve provided in the body of the cylinder T, and by constantly bringing the sealing edge 26a at the tip into sliding contact with the outer peripheral surface of the rolling piston 11 by the elastic force of the spring 26b, the cylinder chamber 10 is set to the low pressure side. It is divided on the high pressure side.

Next, the effect will be explained.

When the compressor is stopped, the cooling and 1% internal pressure is equalized to the pressure determined by the refrigerant vapor pressure, so the pressure is the same on both sides of the check valve 23, that is, in the suction pipe 12 and in the valve storage side space 2ib of the suction passage 21. pressure, and no differential pressure occurs.

Therefore, the check valve 23 is pressed against the head 9 side by the elastic force of the compression coil spring 24, and its sea/l/face 23
The gas inlet 128 is closed at point a (see FIG. 3).

When the compressor starts operating, the volume of the suction side 10a of the cylinder chamber 10 is expanded as the rolling piston 110 rotates (see FIG. 2), and its internal pressure is reduced. Then, the pressure in the valve storage side space 1'141f21b of the suction passage 21, which communicates with the cylinder chamber suction side 10a via the pressure equalization passage 25, also decreases, and the pressure in the suction pipe 12 across the check valve 23 decreases. A differential pressure occurs between the two.

When this differential pressure becomes larger than the spring force of the compression coil spring 24 of the check valve 23 (the spring 24 has a weak spring force that is slightly larger than the sliding resistance of the check valve 23), the check valve 23 is pushed back. and moves into the valve housing side space 21b, and the suction port 1
2a is opened (see Figure 1). As a result, the refrigerant gas from the cooler flows from the suction pipe 12 to the suction port 12a to the suction side space 21a of the suction passage to the suction groove 22 to reach the cylinder chamber 10.
inhaled into the body. At this time, dynamic pressure based on the flow rate of the inflow gas is also applied to the sealing surface 23a of the check valve 23, and the cylinder chamber 1
Coupled with the pressure on the suction pipe 12 side which is slightly higher than the suction side pressure in 0, the check valve 23, which is formed in a cylindrical shape and has a sufficient pressure receiving area, acts in the direction of widening. Therefore, a sufficient inflow area is ensured in the suction side space 21a,
The suction resistance of refrigerant gas on the suction side of the compression element 6 becomes extremely small compared to the conventional case, and the suction efficiency of the compressor is improved.

Next, when the compressor stops, the suction side 10 of the cylinder chamber 1o
a・Suction groove 22・Suction path suction side space 21a・Suction pipe 12
The pressure in each part of the pressure equalizing passage 25 and the suction passage valve storage space 21b is instantly equalized, and the differential pressure between both end faces of the check valve 23 becomes zero.

As a result, the check valve 23 is pressed toward the suction port 12a by the spring force of the compression coil springs 2 and 4, thereby closing the inflow path. Therefore, superheated gas from the high pressure side of the compressor that leaks afterwards can be shut off. Furthermore, since superheated gas pressure is applied as back pressure to the compressed fill spring 24 side of the check valve 23 via the pressure equalization path 25, a self-sealing force acts on the check valve 23. Reliable shutoff is guaranteed. Furthermore, the structure is simple and assembly is easy (no bolts or the like required).

In the above embodiment, the compressed fill spring 24 for pushing the check valve 23 in one direction is provided, but this is not possible when the suction passage 21 is horizontal or because the suction gas flows from above to below. This is intended to be applied to a structure in which a check valve is pushed upward by the elastic force of a spring. On the other hand, in the case of a structure in which the intake gas flows from the bottom to the top,
At the same time as the compressor stops, the check valve falls under its own weight and can perform the check valve function, so in this case, the compression coil spring 2
4 may be omitted and a so-called dead weight closing type may be used.

〔Effect of the invention〕

As described above, the present invention includes slidably inserting a check valve having an outer diameter slightly smaller than the inner diameter of the suction passage into the suction passage of the compression element and having one end as a sealing surface, and Since a pressure equalization path is provided that communicates the stop valve storage space with the cylinder chamber, there is no restriction part for the suction gas passage area, improving the suction efficiency of the compressor and making it easier to save energy in the refrigeration system. be.

[Brief explanation of drawings]

FIG. 1 is a sectional side view of a main part showing a rotary compressor according to an embodiment of the present invention, FIG.
The figure is a cross-sectional side view of the main part showing the closed state of the check valve shown in Fig. 1, Fig. 4 is a cross-sectional side view of the main part showing a conventional rotary compressor, and Fig. 5 is v-■ of Fig. FIG. 1 is a sealed case, 4 is an electric element, 6 is a compression element, 10 is a cylinder k, 12a is an intake port, 21 is an intake passage, 21a
21b is a space on the suction side, 21b is a space on the valve storage side, 23 is a check valve,
24 is a compression coil spring, and 25 is a pressure equalization path. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (2)

[Claims] (1) In a rotary compressor in which a check valve is provided in a suction passage that communicates a suction port of a compression element with a cylinder chamber, the check valve has an outer diameter slightly smaller than an inner diameter of the suction passage. is slidably inserted into the suction passage in the axial direction, and partitions the suction passage into a suction side space and a valve housing side space with the check valve,
A rotary compressor characterized in that the valve storage side space and the cylinder chamber are connected via a pressure equalization path. (2) The rotary compressor according to claim 1, wherein the axis of the suction passage is formed in the direction of gravity action, and the check valve is a self-locking type check valve.