JP2721727B2 - Refrigeration equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a refrigerating apparatus suitable for a refrigerating vehicle or the like having two refrigeration or heat storage compartments.

(Prior Art) FIG. 2 shows an example of a conventional refrigerant circuit of this type of refrigeration apparatus.

As shown in FIG. 2, this refrigerating apparatus has one compressor 1
And one condenser connected to the discharge port of the compressor 1 and a plurality (two in the figure) of evaporators 8 and 11 connected in parallel to the outlet of the condenser 3. .

Table 1 shows the relationship between the operation of each evaporator 8 and 11 of the refrigeration system and the opening and closing of the solenoid valve.

When the evaporators 8 and 11 are to be cooled, the solenoid valves 2, 6, and 9 are opened as shown in Case 1 in Table 1.
The solenoid valves 17, 18 are closed.

Thus, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 enters the condenser 3 via the solenoid valve 2 and radiates heat there to be condensed and liquefied. This liquid refrigerant branches via a receiver 4, one of which enters a first expansion valve 7 via an electromagnetic valve 6, where it is adiabatically expanded by being throttled.
, Where the load is cooled to evaporate. The other branched liquid refrigerant enters the second expansion valve 10 via the electromagnetic valve 9 and is adiabatically expanded by being throttled here, and then enters the second evaporator 11 where the load is cooled to evaporate and evaporate. I do. Next, the pressure of the refrigerant gas is adjusted by an evaporation pressure adjusting valve 14 so that the pressure does not drop below a predetermined pressure.
Merges with the refrigerant gas that has passed through the check valve 12 and enters the accumulator 13, where the unevaporated liquid refrigerant is separated. Thereafter, the pressure enters the suction pressure adjusting valve 16, where the pressure is adjusted, and then the suction is performed by the compressor 1 and compressed again.

When the evaporators 8 and 11 are to be heated, the electromagnetic valves 17 and 18 are opened and the electromagnetic valves 2, 6 and 9 are closed as shown in Case 2 in Table 1.

Thus, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 branches immediately after the discharge, and one of them branches into the first evaporator 8 via the bypass pipe 30 and the solenoid valve 17 interposed therebetween. The temperature is lowered by heating the load with. The other of the branched refrigerant gas enters the second evaporator 11 via the bypass pipe 31 and the solenoid valve 18 interposed therebetween, where the temperature is lowered by heating the load. Next, the refrigerant gas flows out of the first evaporator 8 at a point where the refrigerant gas has passed through the evaporating pressure regulating valve 14 and the check valve 15, and merges with the refrigerant gas that has passed through the check valve 12, and the accumulator 13, It is sucked into the compressor 1 via the suction pressure regulating valve 16.

When the load is cooled by one of the first evaporator 8 and the second evaporator 11 and the load is heated by the other, first, as shown in cases 3 to 6 in Table 1, After cooling or heating the load by suspending its operation by stopping the supply of refrigerant to one of the evaporators and simultaneously supplying all of the refrigerant discharged from the compressor to the other evaporator, The load is heated or cooled by stopping the supply of the refrigerant to the other evaporator and suspending its operation, and at the same time supplying all of the refrigerant discharged from the compressor to the one evaporator.

For example, as shown in Case 3, when the load is cooled by the first evaporator 8 and the load is heated by the second evaporator 11, first, the solenoid valves 2 and 6 are opened, and the solenoid valves 9 and The operation of the refrigerant is stopped by stopping the supply of the refrigerant to the second evaporator 11 by closing 17 and 18, and at the same time, all the refrigerant discharged from the compressor 1 is supplied to the first evaporator 8 By cooling the load. Thereafter, the solenoid valve 18 is opened and the solenoid valves 2, 6, 9, and 17 are closed, so that the first
The operation is stopped by stopping the supply of the refrigerant to the evaporator 8 and the load is heated by supplying all the refrigerant discharged from the compressor 1 to the second evaporator 11.

 Cases 4 to 6 are the same as case 3 above.

(Problem to be Solved by the Invention) In the above-mentioned conventional apparatus, the first evaporator 8 and the second
When the load is cooled in one of the evaporators 11 and the load is heated in the other, the supply of the refrigerant to one of the evaporators is stopped first, and All of the refrigerant discharged from the compressor is allowed to flow, and thereafter, all of the refrigerant discharged from the compressor is passed to one of the evaporators, and at the same time, the supply of the refrigerant to one of the other evaporators is performed. Since the operation is stopped, there is a problem that it is difficult to accurately control the temperature of the load.

(Means for Solving the Problems) The present invention has been made to solve the above problems, and the gist of the first invention is to provide a compressor and a discharge port of the compressor. A plurality of evaporators connected in parallel to the outlet of the condenser, and a plurality of bypass pipes respectively connecting the inlets of the plurality of evaporators and the discharge ports of the compressor. And a plurality of return pipes connecting the outlets of the plurality of evaporators and the outlet of the condenser, and allowing only the flow of the refrigerant toward the outlet of the condenser in each of the return pipes. The refrigeration system is provided with a check valve.

(Operation) In the present invention, when the load is heated by a part of the plurality of evaporators and the load is cooled by the remaining evaporators, the high-temperature and high-pressure refrigerant discharged from the compressor is used. Gas enters a part of the evaporator through a bypass pipe, where it is condensed and liquefied by heating a load, and then enters a remaining evaporator through a return pipe and a check valve interposed therein. The load is cooled by evaporating and returning to the compressor.

(Embodiment) One embodiment of the present invention is shown in FIG.

The outlet of the first evaporator 8 and the outlet of the condenser 3 are connected via a first return pipe 32, and the first return pipe 32 allows only the flow of the refrigerant toward the outlet of the condenser 3. Check valve 22
Is interposed.

The outlet of the second evaporator 11 and the outlet of the condenser 3 are connected via a second return pipe 33, and this second return pipe 33 allows only the flow of the refrigerant toward the outlet of the condenser 3. Check valve 23
Is interposed.

Table 2 shows the relationship between the operation of each evaporator 8 and 11 and the opening and closing of each solenoid valve.

When a cooling action is applied to both evaporators 8 and 11, as shown in Case 1 in Table 2, the solenoid valves 2, 6, 9,.
20 and 21 are opened, and the solenoid valves 17 and 18 are closed.

Thus, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 enters the condenser 3 via the solenoid valve 2 and radiates heat there to be condensed and liquefied. This liquid refrigerant branches via a receiver 4 and a check valve 5, one of which is first branched via a solenoid valve 6.
After being adiabatically expanded by being throttled here, it enters the first evaporator 8 where it evaporates and evaporates by cooling the load, and then the refrigerant gas is passed through the solenoid valve 20, Flow through the stop valve 12.

The other branched liquid refrigerant passes through the solenoid valve 9 and passes through the second expansion valve.
After entering adiabatic expansion by being squeezed here,
The refrigerant enters the second evaporator 11 where it evaporates and evaporates by cooling the load, and then the refrigerant gas is adjusted in pressure by an evaporating pressure regulating valve 14 via an electromagnetic valve 21 so as not to drop below a certain pressure. After that, the refrigerant gas that has passed through the check valve 12 at the place where the check valve 15 has flowed is merged and enters the accumulator 13,
Here, the unevaporated liquid refrigerant is separated. Thereafter, the pressure enters the suction pressure adjusting valve 16, where the pressure is adjusted, and then the suction is performed by the compressor 1 and compressed again.

In the case where both the evaporators 8 and 11 are heated, as shown in Case 2 in Table 2, the solenoid valves 17, 18, 20,
21 is opened and the solenoid valves 2, 6, 9 are closed.

Thus, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 branches immediately after the discharge, and one of them branches into the first evaporator 8 via the bypass pipe 30 and the solenoid valve 17 interposed therein, Here, after the temperature is lowered by heating the load, the load flows through the solenoid valve 20 and the check valve 12. The other of the branched refrigerant gas enters the second evaporator 11 via the bypass pipe 31 and the electromagnetic valve 18 interposed therebetween, and then cools the load by heating the load. Valve 14, check valve 15
At the point where the gas flows, the refrigerant gas merges with the refrigerant gas that has passed through the check valve 12, and is sucked into the compressor 1 through the accumulator 13 and the suction pressure adjusting valve 16.

When the load is cooled by the first evaporator 8 and the load is heated by the second evaporator 11, as shown in the case 3 in Table 2, the solenoid valves 6, 18, and 20 are opened and the electromagnetic valves are opened. Valves 2, 9, 17, 21 are closed.

Thus, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 enters the second evaporator 11 via the bypass pipe 31 and the solenoid valve 18, and is condensed and liquefied by heating the load in the process of flowing through the second evaporator 11. . Next, this refrigerant liquid is supplied to the second return pipe 3.
3. After entering the first evaporator 8 through the check valve 23, the solenoid valve 6, and the first expansion valve 7, where the load is cooled to evaporate, the solenoid valve 20, the check valve 12, Accumulator 1
3. Return to the compressor 1 via the suction pressure regulating valve 16.

When the load is heated by the first evaporator 8 and the load is cooled by the second evaporator 11, as shown in the case 4 in Table 2, the solenoid valves 9, 17, and 21 are opened and the electromagnetic valves are opened. Valves 2, 6, 18, 20 are closed.

Thus, the high-temperature and high-pressure refrigerant gas discharged from the compressor 1 enters the first evaporator 8 via the bypass pipe 30 and the solenoid valve 17, where it is condensed and liquefied by heating the load. Next, the refrigerant liquid is supplied to the first return pipe 32, the check valve 22,
After entering the second evaporator 11 via the solenoid valve 9 and the second expansion valve 10, the load is cooled to evaporate, then the solenoid valve 21, the evaporation pressure regulating valve 14, the check valve 15, the accumulator 13. Return to the compressor 1 via the suction pressure adjusting valve 16.

Although the description has been given of the one having two evaporators, the present invention can be applied to the one having two or more evaporators.

(Effect of the Invention) In the present invention, when the load is heated by a part of the plurality of evaporators and the load is cooled by the remaining evaporator, the load is heated by the compressor to the part of the evaporators The entire amount of the discharged high-temperature and high-pressure refrigerant gas is introduced through a bypass pipe, and the refrigerant flowing through a part of the evaporator is introduced into the remaining evaporator through a return pipe and a check valve. In addition to maximizing the heating capacity of the evaporator, the temperature of the load can be accurately controlled.

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram of one embodiment of the present invention, and FIG. 2 is a refrigerant circuit diagram of a conventional refrigeration apparatus. Compressor… 1, Condenser… 3, Evaporator… 8, 11, Bypass pipe… 30,31, Return pipe… 32,33, Check valves 22,23

Claims (1)

(57) [Claims] 1. A compressor, a condenser connected to a discharge port of the compressor, a plurality of evaporators connected in parallel to an outlet of the condenser, In a refrigerating apparatus including a plurality of bypass pipes respectively connecting an inlet and a discharge port of the compressor, a plurality of return pipes connecting an outlet of the plurality of evaporators and an outlet of the condenser are provided. A refrigeration system characterized in that return pipes are each provided with a check valve that allows only the flow of refrigerant toward the outlet of the condenser.