JPH0733095Y2 - Accumulator oil return device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is applied to a refrigerating cycle such as an air conditioner and a refrigerator, and is an oil of an accumulator for separating refrigerating machine oil and liquid refrigerant from evaporated refrigerating gas. Regarding the return device.

[Conventional technology]

 A system diagram of a conventional air conditioner is shown in FIG.

In the figure, the high-temperature high-pressure gas refrigerant discharged from the compressor 1 enters a condenser 3 via a four-way valve 2, where it is heat-exchanged and condensed to become a low-temperature high-pressure liquid refrigerant. The liquid refrigerant is decompressed by the decompression mechanism 4 such as an expansion valve capillary tube to become a low-temperature low-pressure gas-liquid two-phase flow that is heat-exchanged by the evaporator 5 and evaporated, and then flows into the accumulator 6.

After that, the refrigerant gas separated into the liquid gas in the accumulator 6 passes through the refrigerant gas outlet pipe 9, passes through the compressor suction pipe 19 and the gas-liquid separator 20, and is sucked into the compressor 1 and compressed again.

On the other hand, the refrigerant liquid and the refrigerating machine oil not evaporated in the evaporator 5 are stored in the accumulator 6 in the refrigerant gas outlet pipe 9
It gradually returns to the compressor 1 through the oil return hole 7 drilled in. As a result, a proper amount of refrigerating machine oil is held in the compressor 1, and the refrigerant gas sucked into the compressor 1 is cooled by the liquid refrigerant accompanying the refrigerating machine oil.

[Problems to be solved by the device]

The above conventional air conditioners and the like have the following problems to be solved.

That is, in a conventional air conditioner or the like, the diameter of the oil return hole provided in the refrigerant gas outlet pipe of the accumulator is such that a proper amount of liquid refrigerant returns to the compressor and is drawn into the compressor in accordance with the normal operating load. Since the gas is constantly selected to cool to an appropriate temperature, when the heat absorption amount in the evaporator is small, that is, when the operating load is low, a large amount of liquid refrigerant that is not evaporated in the evaporator is accumulated in the accumulator. A large amount of this liquid refrigerant returned to the compressor from the oil return hole and excessively cools the refrigerant gas sucked into the compressor, which causes a problem that the proper temperature of the compressor cannot be maintained.

[Means for Solving the Problems]

As a means for solving the above problems, the present invention relates to an accumulator provided at an evaporator outlet of a refrigeration cycle such as an air conditioner and a refrigerator, and an oil return pipe that connects a bottom portion of the accumulator and a suction pipe of a compressor, A flow rate control means that is provided in the oil return pipe, detects the dome temperature of the compressor, decreases the return amount of the refrigerating machine oil and the liquid refrigerant from the oil return pipe as the dome temperature becomes lower, and increases it as the dome temperature becomes higher. An oil return device for an accumulator, which comprises:

[Action]

Since the present invention is constructed as described above, it has the following effects.

That is, the oil return pipe is provided in the accumulator so as to communicate with the compressor, and the oil return pipe is provided with a flow rate control means linked to the dome temperature of the compressor, whereby the refrigeration oil and the liquid refrigerant stored in the accumulator are compressed. The amount returned to the machine can be decreased as the temperature of the compressor dome is decreased and can be increased as the temperature of the compressor dome is increased.

As a result, the temperature of the compressor can be maintained within an appropriate range without being affected by fluctuations in the refrigeration cycle operating load.

〔Example〕

A first embodiment of the present invention will be described with reference to FIG. The same components as those of the conventional example are designated by the same reference numerals, and the description thereof will be omitted except when necessary. Hereinafter, the same applies to the second and third embodiments.

In FIG. 1, an oil outlet 12 is provided at the bottom of the accumulator 6, and an oil return pipe 13 that connects the oil outlet 12 and the compressor suction pipe 19 is installed. The oil return pipe 13 is branched in the wake of the oil outlet 12, and one of the branch pipes has a refrigerant controller 15 such as a capillary tube, and the other has a solenoid valve 14a and a refrigerant controller 15a such as a capillary tube. Once installed, the two will merge again and the compressor suction pipe 19
Connected to.

Further, the solenoid valve 14a installed on one side of the branch pipe of the oil return pipe 13 is interlocked with the thermostat 16a in which the temperature sensing portion 16 is arranged on the dome of the compressor 1, so that the temperature of the dome of the compressor 1 is controlled. When the temperature rises by a predetermined temperature, the solenoid valve 14a opens, and conversely when the temperature falls, the solenoid valve 14a closes.

The refrigerating machine oil and the liquid refrigerant thus stored in the accumulator 6 from the evaporator 5 are stored in the refrigerant controller of the oil return pipe 13.
15 and solenoid valve 14a and refrigerant controller 15a, and compressor suction pipe
Merge onto 19 and return to compressor 1. Since the refrigerant gas sucked into the compressor 1 is cooled by this liquid refrigerant, the inside of the compressor 1 is maintained at an appropriate temperature.

On the other hand, the amount of liquid refrigerant returning to the compressor 1 increases and the compressor 1
If the temperature of the compressor is lower than the predetermined temperature, the compressor 1
The solenoid valve 14a is closed by the thermostat 16a in which the temperature sensing portion 16 is arranged on the dome of the compressor, and the liquid refrigerant does not flow through the refrigerant controller 15a. Therefore, the amount of liquid refrigerant returning to the compressor 1 is reduced and the temperature inside the compressor 1 Rises.

Other configurations and operations are similar to those of the conventional one shown in FIG. 4, and corresponding members are designated by the same reference numerals.

As described above, according to this embodiment, the solenoid valve 14a installed in the oil return pipe 13 is opened / closed due to the change in the dome temperature of the compressor 1, and the amount of the liquid refrigerant returned to the compressor 1 is adjusted. The temperature inside the compressor 1 can be maintained within an appropriate range even if there is a load change during operation.

Next, a second embodiment of the present invention will be described with reference to FIG.

As described above, in the first embodiment, the oil return pipe 13 is branched to install the refrigerant controller 15, the solenoid valve 14a and the refrigerant controller 15a.
In the second embodiment, two or more parallel circuits each having an electromagnetic valve and a refrigerant controller are provided as shown in FIG.
Thermostats a, 14b, 14c with different operating temperatures 1
6a, 16b, 16c are interlocked with, and refrigerant controllers 15b, 15c are added so that the amount of liquid refrigerant returned to the compressor 1 is controlled stepwise so as to increase with increasing temperature and decrease with decreasing temperature. It was done.

According to this embodiment, there is an advantage that the fluctuation width can be controlled to be small with respect to the temperature fluctuation of the compressor 1.

Next, a third embodiment of the present invention will be described with reference to FIG.

In FIG. 3, a flow rate control valve 17 is provided in an oil return pipe 13 that connects the oil outlet 12 and the compressor suction pipe 19. The flow rate control valve 17 is a temperature sensing part 18 of the dome of the compressor 1 and a control device.
It is automatically controlled by 18a, and the valve opening degree of the flow rate control valve 17 changes according to the variation difference between the dome temperature of the compressor 1 and a predetermined temperature.

The refrigerating machine oil and the liquid refrigerant thus stored in the accumulator 6 from the evaporator 5 are supplied to the oil return pipe 13 through the flow control valve 17
Through and joins the compressor suction pipe 19 and returns to the compressor 1. In this process, when the temperature of the compressor 1 is equal to the predetermined temperature, the flow rate control valve 17 is maintained at a certain valve opening and the liquid refrigerant flows according to the valve opening. On the other hand, as the temperature of the compressor 1 becomes higher than a predetermined temperature, the valve opening degree of the flow rate control valve 17 increases, the amount of liquid refrigerant returning to the compressor 1 increases, and the temperature of the compressor 1 decreases. On the contrary, as the temperature of the compressor 1 becomes lower than the predetermined temperature, the valve opening of the flow rate control valve 17 becomes smaller, the amount of liquid refrigerant returning to the compressor 1 decreases, and the temperature of the compressor 1 rises. In this way, the compressor 1 is maintained in a constant temperature range.

Other configurations and operations are similar to those of the conventional one shown in FIG. 4, and corresponding members are designated by the same reference numerals. According to this embodiment, there is an advantage that the effect can be obtained with a small number of parts.

As described above, according to the first to third embodiments, the liquid refrigerant stored in the accumulator 6 can be returned to the compressor 1 while controlling the flow rate according to the change in the dome temperature of the compressor 1. There is an advantage that the temperature in the compressor 1 can always be maintained at a predetermined temperature even if the load of the harmony machine or the like changes.

[Advantages of the Invention] Since the present invention is configured as described above, it has the following effects.

That is, while providing the oil return pipe in the accumulator,
By providing the oil return pipe with the flow rate control means linked with the temperature of the compressor dome, the temperature of the compressor can be maintained within an appropriate range without being affected by the load fluctuation of the operation of the refrigeration cycle.

[Brief description of drawings]

FIG. 1 is a system diagram of an oil returning device according to a first embodiment of the present invention, FIG. 2 is a system diagram of an oil returning device according to a second embodiment of the present invention (only the main part is shown), and FIG. FIG. 4 is a system diagram of an oil return device according to a third embodiment of the present invention, and FIG. 4 is a refrigeration system diagram of a conventional air conditioner. 1 ... Compressor, 5 ... Evaporator, 6 ... Accumulator, 12 ...
Oil outlet, 13 ... Oil return pipe, 14a, 14b, 14c ... Solenoid valve, 15, 15
a, 15b, 15c ... Refrigerant controller, 16,18 ... Temperature sensing part, 16a, 16b, 16c
… Thermostat, 17… Flow control valve, 18a… Control equipment, 1
9 ... Compressor suction pipe.

Claims (1)

[Scope of utility model registration request] 1. An accumulator provided at an evaporator outlet of a refrigeration cycle such as an air conditioner or a refrigerator, and an oil return pipe connecting a bottom portion of the accumulator and a suction pipe of a compressor, and the oil return pipe. Flow rate control means for detecting the dome temperature of the compressor to decrease the amount of refrigerating machine oil and liquid refrigerant returned from the oil return pipe as the dome temperature becomes lower, and increase as the dome temperature becomes higher. The oil return device of the accumulator characterized by becoming.