JPH0330766Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a refrigeration device such as a liquid cooler.

[Conventional technology]

Generally, when obtaining constant temperature water lower than room temperature in a constant temperature water tank or the like, a freezing device such as a liquid cooler is used.
That is, a refrigeration circuit is constituted by a compressor, a condenser, a pressure equalizing tube, an evaporator, etc., and the evaporator is placed in a constant temperature water bath to obtain low-temperature water.

By the way, in this type of conventional refrigeration equipment, it is necessary to maintain the water temperature in the constant temperature water tank at a constant temperature, so an immersion electric heater is installed together with the evaporator in the constant temperature water tank, and the compressor is continuously operated. The heater is turned on and off to obtain a constant low temperature water. Here, it is possible to control the water temperature in the water tank to a constant temperature by controlling the operation of the compressor on and off, but depending on the load condition, the time from turning off the compressor to turning it on can be very long. If you attempt to turn on the compressor before the pressure on the high-pressure side and low-pressure side of the refrigeration circuit are equalized, an excessive load will be placed on the motor and there is a risk of starting failure. It is necessary to maintain a constant water temperature while operating the compressor continuously.

[The problem that the idea attempts to solve]

However, although the conventional refrigeration apparatus described above can avoid the risk of startup failure due to on/off control of the compressor, it has the disadvantage that it requires a heater separate from the refrigeration circuit.

In addition, as a method of controlling the evaporator side to a constant temperature while continuously operating the compressor, the discharge side and suction side of the compressor are connected with a bypass pipe equipped with an on-off valve.
It is conceivable to open the on-off valve when the temperature on the evaporator side is detected to be lower than the set temperature and return the discharged gas directly to the suction side.

However, in this case, although part of the discharge gas from the compressor is returned from the discharge side to the suction side, the remaining discharge gas flows to the condenser and evaporator.
Cooling operation will continue, and depending on the load condition, it may become impossible to control the evaporator side to a constant temperature, and a separate heater or the like may be required.

Furthermore, in order to continue operating the compressor, the cooling operation is continued even though the compressor has been cooled to a set temperature or lower, so there is a drawback that power consumption is large.

This invention was made keeping in mind these problems of the conventional technology, and its purpose is to maintain the temperature of the evaporator while continuously operating the compressor without using a heater or the like. The present invention aims to provide a refrigeration system that can maintain a set temperature and can significantly reduce power consumption.

[Means to solve the problem]

In order to achieve the above object, in the refrigeration system of this invention, between the discharge side and the suction side of the compressor, all discharged gas from the compressor is passed through a condenser and an evaporator and returned to the suction side. A four-way valve is provided that can be freely switched between a cooling operation state and a short-circuit operation state in which all gas discharged from the compressor is returned directly to the suction side,
Further, the present invention is characterized in that a thermoswitch is provided that detects the temperature on the evaporator side and operates at a temperature below a set temperature to switch only the four-way valve from a cooling operation state to a short circuit operation state.

[Effect]

In the case of a refrigeration system configured as described above,
When the four-way valve is switched to cooling mode by the thermoswitch that detects the temperature on the evaporator side, all discharged gas from the compressor flows through the four-way valve to the condenser and evaporator and returns to the compressor through the four-way valve. A predetermined cooling operation is performed by the endothermic action in the evaporator.

Additionally, when the thermoswitch detects a temperature below the set temperature on the evaporator side and switches the four-way valve to short-circuit operation, all gas discharged from the compressor will be returned directly to the compressor through the four-way valve. , the condenser and evaporator are separated from the compressor to form a closed circuit with the four-way valve, and the cooling is stopped.

At this time, the refrigerant that is in a liquid state during normal cooling operation is trapped in the closed circuit and cut off from the operating system, so most of the refrigerant charged in this type of refrigeration circuit system is trapped in this closed circuit. This means that only a small amount of refrigerant remains in the operating system consisting of the compressor and the four-way valve, which is the same condition as when only a very small amount of refrigerant is charged, and the compressor is operating under an extremely light load. Therefore, power consumption is significantly reduced.

〔Example〕

Next, this invention will be explained in detail with reference to a drawing showing one embodiment when applied to a liquid cooler.

In the drawing, 1 is a compressor, 2 is a condenser, 3 is a dryer, 4 is a pressure equalizing tube such as a capillary tube, 5 is an immersion type evaporator, and 6 is a connection between the discharge side and the suction side of the compressor 1. It is a four-way valve provided in between, and the four-way valve 6 has four ports a, b, c, and d,
When power is applied to the four-way valve 6, the first and second ports a and b
and between the third and fourth ports c and d, respectively, and when the power supply is stopped, the first and fourth ports a,
d and the second and third ports b and c are communicated with each other.

The discharge pipe A of the compressor 1 is connected to the first port a of the four-way valve 6, and the inlet pipe B of the condenser 2 is connected to the second port b, and the outlet side of the condenser 2 is connected to the dryer 3, It is connected to the inlet side of the evaporator 5 via the pressure equalizing tube 4 and the first flexible tube 7 made of stainless steel, and the outlet side of the evaporator 5 is connected to the four-way valve via the second flexible tube 8 and the connecting pipe C. 3rd of 6
The suction pipe D of the compressor 1 is connected to the port c.
is connected to the fourth port d of the four-way valve 6.

9 is a cooling fan for the condenser 2, 10 is a fan motor, 11 is a liquid cooler unit body,
A compressor 1, a condenser 2, a dryer 3, a four-way valve 6, a fan 9, and a fan motor 10 are housed within the unit body 11. Reference numeral 12 denotes a flexible tube which includes the pressure equalizing tube 4 and both flexible tubes 7 and 8 and connects the unit main body 11 and the evaporator 5;
3 is a constant temperature water tank, and an evaporator 5 is placed in the liquid in the constant temperature water tank 13.

Further, FIG. 3 shows an electric circuit diagram, in which a main switch 15 is connected in series to an AC 100V power supply 14, a compressor 1 and a fan motor 10 are each connected in parallel to the series circuit, and a constant temperature water tank 13 is connected in parallel to the series circuit. A thermoswitch 16 that detects the water temperature inside the compressor and turns off when the temperature is below a set temperature is connected in series to the four-way valve 6, and the series circuit is connected in parallel to the compressor 1.

Next, the operation of the above embodiment will be explained.

After putting the evaporator 5 into the constant temperature water tank 13 which is used at a temperature lower than room temperature, the main switch 15 is turned on.
When turned on, compressor 1 and fan motor 1
0 starts a predetermined drive, and if the water temperature in the constant temperature water tank 13 is higher than the set temperature, the four-way valve 6 is energized via the thermoswitch 16, so the four-way valve 6 operates as shown in FIG. A communication state as shown by the solid line, that is, a cooling operation state is established. Therefore, the gas refrigerant discharged from the compressor 1 enters the condenser 2 through the first and second ports a and b of the four-way valve 6, as shown by the solid line arrow in the figure, and is discharged there. After releasing heat and liquefying, dryer 3 and pressure equalizing thin tube 4
The refrigerant in the evaporator 5 evaporates while taking heat from the water in the constant temperature water tank 13, and is further compressed through the third and fourth ports c and d of the four-way valve. Returning to machine 1, the above-mentioned operation continues,
Due to heat absorption in the evaporator 5, the water temperature in the constant temperature water tank 13 is gradually lowered.

Then, when the water temperature in the constant temperature water tank 13 falls to the set temperature, the thermoswitch 16 is turned off and power supply to the four-way valve 6 is stopped.
is in the communication state shown by the broken line in FIG. 1, that is, the short-circuit operating state. Therefore, most of the charged refrigerant is confined within the closed circuit of the four-way valve 6, condenser 2, dryer 3, pressure equalizing tube 4, evaporator 5, and four-way valve 6, and is completely cooled by air cooling by the cooling fan 9. The gas refrigerant is liquefied and the endothermic action in the evaporator 5 is stopped, while the compressor 1 is continuously operated, so the discharged gas refrigerant flows through the first and fourth ports a and d of the four-way valve 6 as shown by the broken line arrow. is returned to the compressor 1 through the At this time, only a small amount of refrigerant remains in the compressor 1, the four-way valve 6, and the operating circuit of the compressor 1, so the equilibrium pressure between the discharge side and the suction side is maintained low. Accidents such as valve breakage are also less likely to occur.

Furthermore, if the water temperature in the constant temperature water tank 13 rises above the set temperature due to room temperature or load, the thermoswitch 1
6 is turned on, the four-way valve 6 is switched to enter the cooling operation state, and by repeating the above, the water temperature in the constant temperature water tank 13 is maintained at the set temperature.

[Effect of idea]

Since this invention is configured as described above, it produces the effects described below.

A four-way valve is installed between the discharge side and the suction side of the compressor to switch between the cooling operation state and the short-circuit operation state, and only this four-way valve is switched by a thermoswitch that detects the temperature on the evaporator side. The temperature on the evaporator side can be controlled to the set temperature while operating the compressor continuously, avoiding risks such as startup failures that occur when controlling the compressor on and off, and also ensuring that the temperature on the evaporator side does not drop below the set temperature. This eliminates the need for a heater because the cooling operation can be completely stopped when the thermoswitch is turned on or off. By reducing the differential, it becomes possible to frequently intermittent cooling operation, and the temperature of the load can always be maintained close to the set temperature, making it possible to perform more precise temperature control.

Furthermore, in short-circuit operating conditions, the condenser and evaporator circuits containing liquid refrigerant can be completely disconnected from the short-circuit circuit of the compressor, making it possible to operate the compressor at a significantly lighter load, significantly reducing power consumption. This can be reduced to

[Brief explanation of drawings]

The drawings show an embodiment in which the refrigeration system of this invention is applied to a liquid cooler; FIG. 1 is a piping diagram, FIG. 2 is an explanatory diagram of the state of use, and FIG. 3 is an electric circuit diagram. 1... Compressor, 2... Condenser, 5... Evaporator,
6... Four-way valve, 16... Thermo switch.

Claims (1)

[Scope of utility model registration request] Between the discharge side and the suction side of the compressor, there is a cooling operation state in which all the discharged gas from the compressor passes through a condenser and an evaporator and is returned to the suction side, and a cooling operation state in which all the discharged gas from the compressor is passed directly to the suction side. A four-way valve is provided that can freely switch between the short-circuit operating state and the return to the suction side, and
A refrigeration system comprising a thermoswitch that detects the temperature on the evaporator side and operates at a temperature below a set temperature to switch only the four-way valve from the cooling operation state to the short circuit operation state.