JPH0226146B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention was made in order to prevent liquid compression startup that occurs at low temperatures when a refrigeration cycle is used for winter heating.

Conventionally, when starting a compressor at low temperatures, a heater was built into the compressor to prevent liquid compression in the compressor to avoid liquid compression as much as possible.

This invention was made to eliminate the above-mentioned disadvantages, and has the function of quickly gasifying the liquid sent from the receiver to the compressor using a portion of the high-temperature, high-pressure gas discharged from the compressor, thereby preventing liquid compression. It was done for.

Hereinafter, a detailed explanation will be given based on the illustrated embodiment.
1 and 2 are schematic diagrams of a liquid compression prevention device for a refrigeration cycle according to the present invention. In the figures, the same numbers represent the same component parts. In FIG. 1, the flow of refrigerant during steady operation is shown by solid arrows. The high-temperature, high-pressure refrigerant gas compressed by the compressor 1 is liquefied and condensed in the condenser 2, adiabatically expanded in the throttling mechanism 3 to become a low-temperature, low-pressure refrigerant gas, and vaporized in the evaporator 4, which accumulates in the receiver 5 and is compressed again through the suction pipe 8. Inhaled into machine 1.
When the electromagnetic on-off valve 7 opens, a new flow indicated by the broken line arrow in the figure occurs, and a portion of the discharged gas flows into the receiver 5 from the receiver 5 inlet via the bypass path 6. Furthermore, this bypass passage 6 is arranged close to a suction pipe 8 connected from the receiver 5 to the compressor 1, and is configured to perform heat exchange.

When the compressor 1 stops operating, the refrigerant gas and liquid in the condenser 2 pass through the throttling mechanism 3 and mostly accumulate in the evaporator 4 and receiver 5 on the low pressure side. When the compressor 1 starts up again, the refrigerant liquid accumulated in the evaporator 4 and receiver 5 is sucked into the compressor 1 before heat exchange occurs, and the liquid is compressed until the accumulated liquid is exhausted. will continue. By providing the refrigeration cycle liquid compression prevention device according to the present invention, when the compressor is restarted, compressed high temperature and high pressure refrigerant gas is sent into the receiver 5 through the bypass path 6 and is stored there. Heat exchanges with the liquid refrigerant, and the refrigerant gas flows through the suction pipe without containing liquid and is sucked into the suction pipe. At this time, a bypass passage 6 and a suction pipe 8 through which the high-temperature, high-pressure refrigerant gas sent to the receiver 5 passes.
Since the refrigerant is configured to exchange heat with the refrigerant passing through the suction pipe 8, heat is given to the refrigerant passing through the suction pipe 8, and the temperature can be quickly raised to the saturation temperature or higher. Furthermore, in order to efficiently exchange heat within the receiver 6, the open end of the bypass passage 6 may be provided at the bottom of the receiver 5, as shown in FIG.

A control flowchart of the electromagnetic on-off valve 7 of the bypass path 6 is schematically shown. When the compressor 1 starts, the electromagnetic on-off valve 7 is opened, and when a predetermined set time S1 has elapsed, it is closed.

As described above, by providing the liquid compression prevention device of the refrigeration cycle according to the present invention, it has the function of efficiently converting the suction refrigerant from liquid to gas when restarting the compressor, thereby improving reliability. It is possible to achieve advantages such as improved performance and elimination of a heater.

[Brief explanation of drawings]

Fig. 1 is a refrigerant circuit diagram showing one embodiment of the present invention, Fig. 2 is a refrigerant circuit diagram showing another embodiment of the invention, and Fig. 3 is a flowchart showing an example of controlling a bypass electromagnetic on-off valve. . The same symbols in the figures indicate the same or corresponding parts, 1
... Compressor, 2 ... Condenser, 3 ... Throttle mechanism, 4
...evaporator, 5...receiver, 6...bypass path, 7...electromagnetic on-off valve, 8...intake pipe.

Claims (1)

[Claims] 1. In a refrigeration cycle in which a compressor, a condenser, a throttle mechanism, an evaporator, and a receiver are connected in a ring, there is a bypass path that bypasses the refrigerant from the compressor discharge port into the receiver, and a bypass path provided in the middle of this bypass path. , an electromagnetic on-off valve that opens when the compressor is started and closes after a predetermined set time S1 has elapsed;
A liquid compression prevention device for a refrigeration cycle, characterized in that the bypass path is disposed close to the compressor and a compressor suction pipe connected to the receiver so as to exchange heat between the compressor and the receiver.