JP2000321103A - Tester for refrigerating compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tester for a refrigerating compressor having high performance by a gas refrigerant flowmeter method adapted to a small-sized refrigerator. SOLUTION: A differential pressure sensor 14 for sensing a pressure difference between an upper flow and a lower flow of a throttling mechanism 13 of a gas flowmeter 6 for measuring a discharge gas from a compressor under test is provided in a constant temperature case 15e, and a second temperature sensor 15a and a cold heat cooler 15b are provided in the case 15e. A controller 15c for controlling a circumferential temperature of the sensor 14 to the same temperature as a gas refrigerant temperature by the detection of a first temperature sensor 5 of the gas refrigerant of an upstream side of the mechanism 13 is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for testing a refrigerating compressor using a gas refrigerant flow meter method.

[0002]

2. Description of the Related Art Various types of testing methods for refrigerating compressors used in room air conditioners and refrigerators are listed in JIS B 8606, but the gas refrigerant flow rate which is considered to be unsuitable for small refrigerators is described. The test method based on the secondary refrigerant calorimeter method in the evaporator calorimeter method has not been developed, and the test apparatus based on the secondary refrigerant calorimeter method has been mainly used.

[0003]

In the conventional secondary refrigerant calorimeter test apparatus, fluorocarbon gas, which was easily available as a secondary refrigerant, has been used. Recently, however, fluorocarbon gas regulations such as prevention of destruction of the ozone layer have been used. This method has the biggest problem that it becomes difficult to use it.In addition, this method uses a heat balance with an electric heater to calculate the refrigeration capacity to cope with the refrigeration capacity, and has a large power consumption including stabilization control. was there.

An object of the present invention is to solve the above-mentioned problems and to provide a high-precision refrigeration compressor test apparatus using a gas refrigerant flowmeter method which is energy-saving and does not use chlorofluorocarbon gas and is suitable for a small refrigerator. With the goal.

[0005]

SUMMARY OF THE INVENTION In order to attain the above object, the present invention measures a flow rate of a refrigerant discharged from a test compressor flowing in a cycle and tests a refrigeration capacity of the compressor. In the gas flow meter, temperature control means for controlling the peripheral temperature of the differential pressure sensor for detecting the pressure difference between the upstream and downstream of the throttle mechanism of the gas flow meter to the same temperature as the gas refrigerant temperature on the upstream side of the throttle mechanism. It is characterized by having been provided.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a refrigerating compressor test apparatus according to an embodiment of the present invention. In the refrigerating test cycle, the gas refrigerant flow meter method of JIS B 8606 uses the suction side or discharge side of the compressor. A gas flow meter is provided on either side of the discharge side, but according to the present invention, the test method is based on the gas flow rate on the discharge side.

In the test apparatus 1, a test compressor 2
Pressure / thermometers 3 are provided at predetermined positions on the suction side and the discharge side for measurement at the same location, respectively, and the refrigerating cycle pipeline is connected from the discharge port 2a of the compressor 2 to the suction port 2b. 10, an oil separator 4, a first temperature sensor 5 for detecting gas temperature, a gas flow meter 6 including a throttle mechanism 13 and a differential pressure sensor 14, a condenser 7, a liquid receiver 8, a first flow rate A control valve 10a and a gas cooler 9 are sequentially interposed, and a second flow control valve is provided in a bypass line 11 branched from the refrigeration cycle line 10 upstream of the condenser 7 to the gas cooler 9. A third flow control valve 12a is interposed in an oil return line 12 which is interposed between the refrigeration cycle line 10 and the oil separator 4 on the suction side of the compressor 2 and has an oil return line 11a. Have been.

The feature of the present invention resides in the gas flow meter 6.
The gas flow meter 6 includes a small-diameter pipe throttle mechanism 13 and a differential pressure sensor 14 whose ambient temperature is controlled to measure a flow rate based on a pressure difference between the upstream and downstream of the throttle mechanism 13.

In FIG. 2, a throttle mechanism 13 comprises a pipe 13a having a pipe diameter D, a nozzle 13b having a nozzle diameter d and a nozzle length L, and is a JIS Z 8 for measuring a gas flow rate.
In the throttle mechanism described in 762, the pipe diameter D is 50 m for the pump.
Although it is shown from m to 1200 mm, it is too thick for a compressor and not suitable for the capacity of a small refrigerator. As a result, the tube diameter D of the low Reynolds number was 4 mm to 12 mm, and the nozzle diameter d was 2 mm to
It is possible to obtain a throttle mechanism 13 for a small-diameter pipe suitable for household air conditioners, room air conditioners, refrigerators, small refrigerators, and the like by using several combinations of 8.4 mm and a nozzle length L of 4 mm to 23 mm. Was.

By using this small diameter pipe as the throttle mechanism 13, it is possible to measure a small flow rate with high accuracy.

The differential pressure sensor 14 is connected to the nozzle 1
Small chambers 13c respectively communicating with the pipes 13a on the upstream and downstream sides of 3b,
Measure the differential pressure of 13d.

Since the measured value of the differential pressure sensor 14 varies depending on the temperature, it is necessary to make the ambient temperature of the differential pressure sensor 14 equal to the gas refrigerant temperature by the temperature control means 15 in order to obtain an accurate measured value. There, the differential pressure sensor 14 is provided in a constant temperature box 15e, and in the box 15e, a second temperature sensor 15a for detecting the temperature in the box 15e is heated or cooled. A heater 15b is provided, and the second temperature sensor 15a and the cooling / heating unit 15b are connected to the controller 15b.
c, the controller 15b and the first temperature sensor 5 on the upstream side of the flowmeter 6 were connected by a signal line 15d indicated by a dotted line, and the temperature was controlled by the controller 15c.

By means of the temperature control means 15 composed of these, the gas refrigerant temperature and the ambient temperature of the differential pressure sensor 14 become the same, and an accurate measurement value without a temperature error of the differential pressure sensor 14 can be obtained.

Next, a method of using the test apparatus 1 for a refrigerating compressor according to one embodiment of the present invention will be described with reference to the drawings.

First, the test compressor 2 is equipped with all the auxiliary devices necessary for normal operation, and the specified refrigerant and lubricating oil are filled in, thereby completing the preparatory work.

Next, when the test compressor 2 is operated, a discharge gas containing a small amount of oil from the discharge port 2a of the test compressor 2 enters the oil separator 4, and is separated into a gas refrigerant and a lubricating oil. The gas refrigerant passes through the gas flow meter 6 in a superheated state, and the flow rate is measured. Further, about 1/5 of the gas refrigerant is diverted to the condenser 7, and the condenser 7 has a coil shape in which cooling water flows outside. The superheated gas refrigerant formed by the double pipe 7a
The heat is released to the cooling water to liquefy and enter the receiver 8, and the remaining about 4/5 of the gas refrigerant is diverted to the bypass pipe 11, and is diverted to the gas cooler 9 through the second flow control valve 11a. Into the first flow control valve 10a.
Injecting into the gas cooler 9 whose flow rate has been adjusted and decompressed, the remaining about 4/5 of the superheated gas is cooled in the gas cooler 9 and the combined gas refrigerant having dropped to a predetermined temperature is It is sucked into the suction port 2b of the test compressor 2 to form a series of test cycles.

The lubricating oil separated by the oil separator 4 is again returned from the suction port 2b to the test compressor 2 by the oil return line 12.
Return inside.

In the above test cycle, the gas flow meter 6 of the present invention can perform accurate measurement without a temperature error by a differential pressure sensor whose ambient temperature is controlled to the same temperature as the gas refrigerant temperature. The measurement of a small flow rate can be performed with high precision by the restriction mechanism of the pipe.

That is, in the gas flow meter 6, the first detected temperature of the first temperature sensor 5 and the second temperature sensor 15a
The controller 15c having input the second detected temperature outputs a control signal to the cooling heater 15b so that the second detected temperature becomes equal to the first detected temperature, and the difference is generated by the heating or cooling action from the cooling heater 15b. The ambient temperature of the pressure sensor 14 is
b to be equal to the temperature of the gas refrigerant flowing through it.

Furthermore, the test apparatus using the gas refrigerant flow meter method of the present invention not only does not use chlorofluorocarbon gas, but also uses a gas flow meter capable of measuring a small flow rate regardless of the type of refrigerant, so that the amount of refrigerant used is almost half. , The power energy consumed by the entire apparatus can be reduced to 1/3 to 1/10, and the installation space can be halved.

[0022]

As described above, according to the present invention, by controlling the ambient temperature of the differential pressure sensor of the gas flow meter to be the same as the gas refrigerant temperature without using chlorofluorocarbon gas, an accurate measurement without a temperature error can be obtained. With a throttle mechanism capable of measuring a small flow rate, a large energy saving effect of the test cycle can be obtained.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a test apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a main part thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Test apparatus 2 Compressor under test 6 Gas flow meter 13 Throttle mechanism 14 Differential pressure sensor 15 Temperature control means

Claims (3)

[Claims] 1. A test apparatus for measuring the flow rate of refrigerant discharged from a test compressor flowing through a cycle and testing the refrigerating capacity of the compressor, wherein a gas flow meter is provided with a throttle mechanism of the gas flow meter. A refrigerating compressor test apparatus, comprising: temperature control means for controlling a temperature around a differential pressure sensor for detecting an upstream and downstream pressure difference to be the same as a gas refrigerant temperature upstream of the throttle mechanism. 2. The temperature control means includes: a constant temperature box provided with the differential pressure sensor therein; a first temperature sensor provided near the throttle mechanism; a second temperature sensor provided in the constant temperature box; A heating / cooling heater, and a detection temperature of the first temperature sensor and a detection temperature of the second temperature sensor.
2. A controller for outputting a control signal to said cooling / heating unit in accordance with the temperature difference between the detected temperatures.
A testing device for a refrigerating compressor according to item 1. 3. The throttle mechanism according to claim 1, wherein the throttle mechanism comprises a small-diameter pipe having a low Reynolds number corresponding to a small flow rate of a gas refrigerant flow of a small capacity compressor such as a home air conditioner or a refrigerator. Refrigeration compressor testing equipment.