JPH0219384B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a refrigerant control valve used in a refrigeration cycle unit that uses a high-pressure closed container type compressor, such as a rotary compressor, and has, for example, a capillary tube disposed in a pressure reducer.

In general, in refrigeration equipment that controls the cooling temperature by controlling the ON/OFF operation of the compressor,
Cooling efficiency during compression operation is generally improved by improving suction efficiency by adopting a direct suction system that eliminates the need for a suction valve. However, due to the valve structure that eliminates the need for a suction valve and the fact that the inside of the compressor shell (high-pressure sealed container) is on the high-pressure side, when the compressor is stopped, the pressure balance between the high-pressure side and the low-pressure side of the refrigeration system is different from that of a reciprocating compressor. This is done through a capillary tube, which is a pressure reducer, whereas in equipment that uses a rotary compressor, refrigerant is also sent from the compressor to the cooler through the suction pipe to balance the pressure. A flow occurs. In addition, in a rotary compressor, since the inside of the compressor shell is on the high pressure side, the capacity on the high pressure side is large, and as a result, the appropriate amount of refrigerant to be filled is larger than when a reciprocating type compressor is used. From the above points, in a system that uses a rotary compressor, when the compressor is stopped, a larger amount of high-pressure refrigerant flows into the cooler than when a reciprocating type compressor is used, and the pressure is balanced, so these high-temperature refrigerants When viewed as a whole, cycling operation, which repeatedly starts and stops, has the drawback that the improvement in cooling efficiency due to improved refrigerant suction efficiency during operation is diminished by the increase in heat load when stopped as described above. . Therefore, in order to apply the rotary compressor to refrigeration equipment more efficiently, a check valve (check valve) should be installed in the middle of the suction pipe, and a solenoid valve should be installed at the inlet of the capillary tube to close it when the compressor is stopped. It is necessary to prevent high-temperature refrigerant from flowing into the cooler by methods such as However, this method requires a check valve, an electromagnetic valve, and an electromagnetic coil, which increases the number of parts and has disadvantages such as an increase in power consumption due to energization of the electromagnetic coil.

The present invention aims to solve these drawbacks by providing a relatively simple refrigerant control valve to a refrigeration system, and one embodiment thereof will be described in detail below with reference to the drawings.

In the figure, 1 is a rotary compressor, 2 is a condenser, 3 is a capillary tube, 4 is a cooler, and 5 is a condenser.
is a suction pipe and constitutes a known refrigeration cycle. 6 is a refrigerant control valve which is the subject of the present invention. The structure of this refrigerant control valve 6 will be explained. The valve body outer shell 6a includes a high pressure inflow connection pipe 7 (hereinafter referred to as the condenser outlet connection pipe) connected to the outlet of the condenser 2, and a high pressure outflow connection pipe 8 connected to the capillary tube.
(hereinafter referred to as the capillary connection pipe), a low pressure inflow connection pipe 9 connected to the suction pipe 5 (hereinafter referred to as the suction pipe inlet connection pipe), and a low pressure outflow connection pipe 10 connected to the compressor suction pipe 17 (hereinafter referred to as the suction pipe outlet connection). pipe) is provided. Reference numeral 11 denotes a bellows fixed to the base 6b below the valve body outer shell 6a, and this bellows 11 connects the inside of the valve body outer shell 6a to the high pressure side flow path 6c outside the bellows 11 and the low pressure side flow inside the bellows 11. It is divided into 6d roads.

The condenser outlet connecting pipe 7 and capillary connecting pipe 8 described above are each connected to the high pressure side flow path 6c, and the suction pipe inlet connecting pipe 9 and the suction pipe outlet connecting pipe 10 are respectively connected to the low pressure side flow path 6d. It is connected. Further, a ball-shaped high pressure side valve 13 is set on the upper surface of the bellows 11 and is provided on a valve pedestal 12 fixed to the bellows 11. This valve 13 closes a high-pressure valve seat 12a formed on the upper base 6e of the outer valve body 6a when the bellows is extended. That is, the high pressure side flow path 6c is closed. Also bellows 11
Inside, a cylindrical stopper member 14 is fixed to the back surface of the upper surface of the bellows, and the diameter of the lower end reduced diameter part 14a is larger than the diameter of the recessed part 6f provided in the base 6b, and the lower diameter reduced part 14a is smaller than the recessed part 6f. 1
4a is a suction pipe inlet connection pipe 9 of the valve body outer shell 6a
A recess 6f provided in the lower base 6b connected to the
When the bellows is contracted, the step part 14b of the lower end reduced diameter part 14a comes into contact with the shoulder part 6g of the concave part 6f to prevent over-contraction, and at the same time, it is a very light flaky floating regulating member for the low pressure side valve 15. Also serves as Further, when the stepped portion 14b abuts the shoulder portion 6g on the lower end reduced diameter portion 14a of the stopper member 14, the recessed portion 6
A notch 16 is provided to communicate the gap formed between the inner periphery of f and the outer periphery of the lower end reduced diameter portion 14a and the low pressure side flow path 6d in the bellows 11, and when the above-mentioned flaky valve 15 floats, , constitutes a conduction circuit between the suction pipe inlet connecting pipe 9 and the suction pipe outlet connecting pipe 10. With this configuration, when the refrigerant cycle unit is not filled with refrigerant gas, that is, when the valve body is a single unit, the high-pressure side valve 13 has a contact force that closes the high-pressure side flow path 6c connected to the capillary tube connection pipe.
P ₁ is the pressure difference P ₂ when the difference between high and low pressures is the smallest among the operating conditions to which the refrigeration equipment is applied.
It is set so that P ₂ > P ₁ .

The operating state will be explained below. The drawing shows the state of the rotary compressor 1 during operation. In this case, the refrigerant flows as shown by the solid arrow, that is, the high pressure side flow path 6
c becomes a high pressure, and the inside of the bellows 11, that is, the low pressure side flow path 6d, becomes a low pressure, and the differential pressure _P2 becomes larger than the valve closing contact force _P1 of the high pressure side valve 13, which is the initial characteristic of the bellows 11. The high pressure side flow path 6c on the side of the capillary tube connection pipe 8 is opened.
Also, a suction pipe inlet connection pipe 9 for the suction pressure and the return gas flow from the cooler 4 via the suction pipe outlet connection pipe 10.
The low pressure valve 15 becomes flaky due to the blowing force.
is raised as shown in the figure, and eventually both the high and low pressure side valves 13 and 15 are opened and refrigeration operation is performed. Further, in this case, even if the pressure difference between the high pressure side pressure and the low pressure side pressure is large, and the shoulder portion 6g of the lower base 6b and the reduced diameter step portion 14b of the stopper member 14 are close to each other or come into contact with each other, the lower end reduced diameter portion of the stopper member 14 1
The low-pressure side flow path is secured by the notch 16 provided in 4a, and at the same time, refrigeration operation is performed without increasing the resistance of the low-pressure side refrigerant flow path.

Next, when the rotary compressor 1 stops, the high pressure gas in the compressor flows through the compressor suction pipe 17 and from the suction pipe outlet connection pipe 10 of the refrigerant control valve 6 into the low pressure side flow path 6d as shown by the chain arrow. Due to this gas pressure and the weight of the low pressure valve 15, the suction pipe inlet connecting pipe 9 is dropped and sealed. Almost at the same time, the pressure inside the bellows 11 (low-pressure side flow path 6d) rises and becomes the same as the pressure on the high-pressure side, that is, the outer peripheral part of the bellows 11 (high-pressure side flow path 6c), and the high-pressure valve 13, which is the initial characteristic of the bellows 11, rises. The closing force P ₁ closes the high-pressure side flow path 6c on the capillary connecting tube 8 side, and the refrigerant flowing to the cooler 4 through the capillary tube 3 of the high-temperature refrigerant on the high-pressure side when the rotary compressor is stopped, and the suction This prevents the flow of refrigerant from flowing into the cooler through the pipe 5 and prevents the heat absorption load of the cooler 4 from entering.

As described above, the present invention uses a relatively simple valve equipped with a bellows to cool high-pressure and high-temperature gas through the capillary tube and suction pipe when the compressor is stopped in a refrigeration system using a rotary compressor. This prevents the refrigerant from flowing into the cooler and causing an endothermic load on the cooler, and since the amount of refrigerant held on the high pressure side increases when the compressor is stopped, the amount of refrigerant circulating increases when the next compressor starts. This has the effect of improving cooling efficiency and reducing the evaporation temperature of the cooler more quickly. In addition, during compressor operation, the outer periphery of the bellows becomes a condensed refrigerant flow, and the inside of the bellows becomes a flow of low-temperature return gas, which promotes heat exchange between each refrigerant through the bellows, which has the advantage of increasing the refrigeration effect. are doing. Further, the outer periphery of the bellows is used as a high-pressure side flow path, and the inside thereof is used as a low-pressure side flow path, and a stopper member is provided inside the bellows and hangs down opposite to a low-pressure side valve that operates as a check valve provided in this low-pressure side flow path. Because of this, the overall shape of the valve can be made compact, thereby preventing excessive deformation of the bellows, and restricting the movement of the low pressure side valve with a simple configuration. Further, even if the low pressure side valve comes into contact with the end face of the reduced diameter portion of the stopper member, the refrigerant flow path is secured by the notch.

[Brief explanation of drawings]

The drawing is a refrigeration cycle piping diagram showing an embodiment to which the refrigerant control valve of the present invention is applied. 6a... Valve body shell, 11... Bellows, 6c
...High pressure side flow path, 6d...Low pressure side flow path, 7...High pressure inflow connection pipe, 8...High pressure outflow connection pipe, 9...Low pressure inflow connection pipe, 10...Low pressure outflow connection pipe, 13...High pressure side valve, 15...Low pressure Side valve, 14...stopper member.

Claims (1)

[Claims] 1. A bellows is disposed inside the outer shell of the valve body, and the outer side of the bellows and the outer shell of the valve body are used as a high-pressure side flow path connecting the condenser outlet and the capillary tube inlet, and a high-pressure inflow passage connecting the condenser outlet. A connecting pipe and a high-pressure outflow connecting pipe connected to the capillary tube inlet are arranged, and the inside of the bellows is used as a low-pressure side flow path connecting between the suction pipe from the cooler and the compressor suction pipe, and A low-pressure inflow connection pipe that connects to the suction pipe from the cooler and a low-pressure side outflow connection pipe that connects to the compressor suction pipe are provided, and the high-pressure side flow path is provided with a pressure difference between the high-pressure side pressure and the low-pressure side pressure. is below a predetermined value, the bellows is provided with a high-pressure valve that closes the high-pressure side outflow connection pipe side, and a cylindrical stopper member is provided at the upper end of the inside of the bellows, facing the low-pressure side valve that acts as a check valve. The lower end of this stopper member is located in a recess provided in the lower base of the outer shell of the valve body which communicates with the low pressure side inflow connection pipe and accommodates the low pressure side valve, and when the bellows is contracted, the stopper member is located in a recess provided in the lower base of the valve main body outer shell which communicates with the low pressure side inflow connection pipe and houses the low pressure side valve. A stopper member including the diameter-reducing step portion of the lower end diameter-reducing portion is provided with a lower end diameter-reducing portion having a diameter-reducing step portion abutting the lower end diameter-reducing step portion, and the stopper member including the diameter-reducing step portion of the lower end diameter-reducing portion is in a state where the diameter-reducing step portion is in contact with the shoulder portion of the recessed portion. and a fluid control valve provided with a notch that communicates a gap formed by the outer periphery of the lower end reduced diameter portion and the inner periphery of the concave portion with a low pressure side flow path formed inside the bellows.