JPH0145023Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a testing device for compressors used in refrigeration, air conditioning, etc., and is particularly suitable for durability testing of compressors.

In conventional load control devices for testing compressors for refrigeration and air conditioning, all of the refrigerant discharged from the compressor is completely condensed and liquefied using cooling water, and then the refrigerant is drained from the condenser and heated and evaporated using an electric heater to supply the compressor to the compressor. Because it is inhaled, two water tanks, two heat exchangers, cooling water, and an electric heater are essential components, which means that the equipment is large and consumes a large amount of cooling water and electricity. It has its drawbacks.

For example, in the test apparatus shown in FIG. 1, refrigerant discharged from a compressor 1 flows into a condenser 2 and is cooled and liquefied. At this time, the refrigerant pressure on the discharge side of the compressor 1 is fed back to the water supply valve 12 by a pressure detection circuit (not shown), and the amount of cooling water flowing into the water tank 6 is adjusted to be maintained at a set value. The liquid refrigerant in the receiver 3 becomes low pressure and low temperature at the expansion valve 4 and flows into the evaporator 5. Here, the low-temperature liquid refrigerant is heated and evaporated by the hot water flowing in from the condenser water tank 6 and the electric heater 10. The pressure inside the evaporator 7 at this time is adjusted by the input current of the heater and the amount of hot water flowing in.

FIG. 2 shows a Mollier diagram for the testing apparatus of FIG. 1.

The pressure at the compressor discharge refrigerant pressure point is maintained at a set value by controlling the condensing function and is cooled by the condenser to point b. The liquid refrigerant at point b is depressurized by the expansion valve and becomes the state at point c (low pressure, low temperature). c.
The refrigerant at the point flows into the evaporator and is heated and evaporated,
It will be point d. Note that the pressure at point d is adjusted to a value appropriate for the suction gas by the heating amount of the evaporator, and the temperature is adjusted by adjusting the flow rate of the expansion valve.

In order to eliminate the drawbacks of the above test equipment, the present invention is equipped with a pressure regulating valve and a bypass circuit for high-temperature gas refrigerant.
By heating the low-temperature liquid refrigerant with this high-temperature gas refrigerant, it is possible to eliminate the evaporator from conventional equipment and reduce the capacity of the condenser, resulting in a compact, lightweight,
Low cost and low energy consumption during use (cooling water consumption,
The aim is to provide a compressor testing device that consumes less power (heater power consumption).

The configuration of the present invention will be explained below according to the embodiments shown in the drawings.

The discharge gas of the test compressor 1 is controlled by the discharge pressure regulating valve 2.
The set pressure is maintained by 0, and the discharge pressure regulating valve 2
A part of the high temperature gas refrigerant that has passed through the condenser 21
It flows into the receiver tank 22 after being liquefied.
At this time, the capacity of the condenser 21 is set to a value sufficient to make the condensation pressure inside the condensation pressure equal to or lower than the set pressure of the discharge pressure regulating valve 20. The liquid refrigerant in the receiver tank 22 is depressurized by the expansion valve 23 and flows into the accumulator tank 24 as a low-temperature liquid refrigerant.

On the other hand, the high temperature gas refrigerant flowing into the bypass pipe 26 from the high temperature gas pipe 25 is reduced in pressure to the suction set pressure of the compressor 1 by the pressure regulating valve 27, and then flows into the accumulator tank 24 and then from the expansion valve 23. The inflowing low-temperature liquid refrigerant is heated and evaporated.

At the same time, the temperature sensing cylinder 28 detects the degree of superheat of the gas refrigerant flowing out from the accumulator tank 24 and sends feedback to the expansion valve 23.
The degree of superheating is maintained at an appropriate value by adjusting the flow rate of the liquid refrigerant passing through 3. Note that this occurs due to changes in the rotational speed of the compressor and changes in the flow rate of the liquid refrigerant. Changes in suction refrigerant pressure are detected by the pressure regulating valve 27 and automatically adjusted.

The above-mentioned change in the refrigerant will be explained with reference to FIG. 4 (cycle on Mollier diagram).

The refrigerant discharged from the compressor 1 is held at point A by the discharge pressure regulating valve 20, and a part of the high-temperature, high-pressure refrigerant that has passed through the discharge pressure regulating valve 20 is cooled and liquefied in the condenser 21, reaches point C, and passes through the expansion valve. 23, the state of point D (low pressure and low temperature) is reached, and the accumulator tank 24
flows into. On the other hand, the gas refrigerant that has flowed into the bypass circuit 26 as a high-temperature gas is reduced in pressure to point E by the pressure regulating valve 27 and flows into the accumulator tank 24, where it is mixed with the low-temperature refrigerant at point D and E. The high-temperature refrigerants at the point are mixed, resulting in a state at point F (a state appropriate for the compressor suction gas conditions). Note that the pressure at point F is mainly automatically adjusted by the pressure regulating valve 27, and the temperature is automatically adjusted by the expansion valve 23.

As described above, according to the configuration of the present invention, by mixing the high-temperature gas refrigerant and the low-temperature liquid refrigerant in the refrigeration cycle, the compressor suction gas can be adjusted to conditions suitable for the compressor suction gas refrigerant. The conventional evaporator is no longer necessary, and at the same time, the heat source for heating the evaporator is also no longer necessary. Furthermore, since the flow rate of refrigerant flowing into the condenser is approximately 1/3 that of the conventional system, the condenser capacity can also be reduced to approximately 1/3 of that of the conventional system. Therefore, it becomes possible to significantly reduce the size and weight of the device, and also to reduce manufacturing costs and save energy consumption during use.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram of a conventional compressor testing device, Figure 2
3 is a circuit diagram of a compressor testing device according to the present invention, and FIG. 4 is a Mollier diagram of the device shown in FIG. 3. 1... Test compressor, 21... Condenser, 22...
... Receiver tank, 23 ... Expansion valve, 24 ... Accumulator tank, 26 ... Bypass piping,
27...Pressure regulating valve.

Claims (1)

[Scope of utility model registration request] When a compressor, a condenser, a receiver tank, an accumulator tank, etc. are connected by piping and a durability test of the compressor is performed, a bypass pipe is installed in the middle of the piping between the compressor and the condenser, and the receiver The bypass pipe is connected to the downstream side of the expansion valve provided between the tank and the accumulator tank to mix high temperature gas refrigerant and low temperature liquid refrigerant, and a pressure regulating valve is provided in the middle of the bypass pipe. Features of compressor testing equipment.