JPS6215734Y2 - - Google Patents

Description

[Detailed explanation of the idea]

This idea uses two condensing units in one condensing unit.
Applicable to refrigeration systems that operate two cooling units simultaneously or one unit independently, such as two-chamber switching air conditioners, vending machines that handle cold products, show cases, etc. Regarding refrigeration equipment. In this type of refrigeration system, the conditions change depending on whether the two cooling units are operated simultaneously or independently, and therefore it is necessary to adjust the amount of refrigerant in excess or deficiency depending on the operating state. In addition, especially when a capillary tube is used as a refrigerant pressure reduction element, it is necessary to match the resistance value of the capillary tube according to each operating condition in order to quantify and supply the flow of refrigerant to each cooling unit. becomes. Furthermore, if the capacities of the two cooling units are different, troublesome problems arise in order to ensure stable operation, such as matching the resistance values of the capillary tubes and adjusting the amount of refrigerant. This invention was made in consideration of the above points, and its purpose was to temporarily create two
Even if the capacities of the cooling units are different, when two units are operated simultaneously or one unit is operated independently, each cooling unit can exert sufficient cooling capacity without causing excess or deficiency of refrigerant or uneven cooling. The object of the present invention is to provide a new refrigeration system that can be operated. This invention will be described in detail below based on illustrated embodiments. The illustrated embodiment shows an example of a two-chamber switching type air conditioner, and in FIG. 1, 10 is an outdoor unit as a condensing unit;
A and 20B are two indoor units as cooling units with different capacities, and 30 is a refrigerant piping path 40 connecting the outdoor unit and each indoor unit.
This is an operation switching unit inserted in the middle of the The outdoor unit 10 includes a compressor 11, a condenser 12,
The indoor units 20A and 20B are equipped with an accumulator 13 and an outdoor fan 14, and the indoor units 20A and 20B are equipped with evaporators 21A and 21B and indoor blower fans 22A and 22B.
It is equipped with. In addition, the switching unit 30 has an inlet port a connected to a high pressure liquid line 41 drawn out from the outlet of the condenser 12 of the outdoor unit 10, and a four-way valve 31 for switching to independent operation, and two ports c and d of the four-way valve 31. Two sets of parallel branch lines 32A, 33A and 32 are drawn out toward the inlet side of the evaporators 21A and 21B of each indoor unit, respectively.
B, 33B, and capillary tubes 34A, 3 for simultaneous operation inserted and connected to branch lines 32A, 32B drawn out from port c of the two ports.
4B and branch line 33 drawn out from port d
Capillary tubes 35A, 35B for independent operation inserted and connected to A, 33B, two-way solenoid valve 36
A, 36B, and liquid receivers 37A, 37B are installed to form a switching control circuit as shown.
Further, the outlet sides of the evaporators 21A and 21B are respectively connected to a low pressure gas line 42 connected to the suction side of the outdoor unit 10, and port b of the four-way valve 31 is also connected to the low pressure gas line 42.
Here, the operation of the four-way valve 31 is shown in FIG. The four-way valve operates as shown in Figure 2 A and B depending on whether it is energized (ON) or de-energized (OFF). On the other hand, the capillary tubes 34A and 34B are connected to the indoor unit 20A,
Each evaporator 21A, 2 is operated simultaneously with evaporator 20B.
Each resistance value is matched and set according to the capacity of the indoor unit so that an appropriate amount of refrigerant can be dividedly supplied to 1B. On the other hand, capillary tube 35A
and 35B are indoor units 20A and 20B, respectively.
Each resistance value is set so that an appropriate amount of refrigerant can be supplied when each is operated independently. Further, the two-way solenoid valves 36A and 36B open when energized (ON) and close when de-energized (OFF). Next, the operation of the two-chamber switching air conditioner having the above configuration will be described. First, the operation of the valve in each operating state is as shown in the table below.

[Table] As is clear from the above valve operation table, during simultaneous operation, the refrigerant flows through ports a to c of the four-way valve 31, passes through the capillary tubes 34A and 34B, flows into the evaporators 21A and 21B, and flows into the outdoor unit 10 and each A refrigeration cycle is constructed between the indoor units 20A and 20B. In addition, in this state, the liquid receiver 37A is opened to the low pressure side through the port d→b of the four-way valve 31, and the liquid receiver 37B is also opened to the low pressure side through the capillary tube 35B and becomes empty, so that all the refrigerant charged is used for operation. There will be no refrigerant shortage.
Next, when only the indoor unit 20A is operated independently, the refrigerant is supplied from ports a to d of the four-way valve 31 through the capillary tube 35A. In this state, the indoor unit 20B on the idle side is opened to the low pressure side, so the refrigerant on the indoor unit 20B side, including the refrigerant stored in the liquid receiver 37B, is pumped down and maintained at a low pressure. On the other hand, in the indoor unit 20A on the operating side, surplus refrigerant is stored in the liquid receiver 37A and the accumulator 13 to adjust the excess or deficiency of refrigerant. Furthermore, when the indoor unit 20B is switched to independent operation, refrigerant is supplied from ports a to d of the four-way valve 31 through the capillary tube 35B. Therefore, since the liquid receivers 37A and 37B located on the front side of the two-way solenoid valve 36A are both inserted into the high-pressure liquid line, each functions as a liquid receiver and stores excess refrigerant. Adjust the amount of refrigerant. In this case as well, the indoor unit 20A on the idle side is opened to the suction side and maintained at a low pressure to prevent liquid back up and protect the compressor at the next operation changeover. Further, the circuit of the switching unit 30 in the embodiment shown in FIG. 1 can be partially modified to have a circuit configuration as shown in FIG. 3. Compared to the embodiment shown in FIG.
A bypass capillary tube 39 is connected astride between the outlet side of the liquid receiver 37B and the low pressure side line 42 at B. Also branch line 3
3B is pulled out and branched from a position in front of the liquid receiver 37A. In particular, the check valves 38A and 38B prevent the short circuit of the refrigerant circuit forming the refrigeration cycle during independent operation, and the bypass capillary tube 39 is used to adjust the balance of refrigerant flow during operation. In addition, it serves as a bypass line to open the liquid receiver 37B to the suction side during simultaneous operation or when the indoor unit 20A is operated independently. The resistance value of the bypass capillary tube 39 must be determined within a range that does not interfere with the independent operation of the indoor unit 20B, and naturally the resistance value must be matched with that of the capillary tube 35B. As mentioned above, according to this invention, when two cooling units correspond to one condensing unit and operate simultaneously or independently, problems such as excessive or insufficient amount of refrigerant and resistance of the capillary tube can be solved. Value matching can be cleverly resolved, and correct operation can be performed to always exhibit a predetermined cooling capacity with an appropriate amount of refrigerant, regardless of whether simultaneous or individual operation is performed. Note that this invention is not limited to the two-chamber air conditioner shown in the illustrated embodiment, but can also be used to simultaneously or independently operate two cooling units such as a vending machine or a refrigerated case with one condensing unit. Of course, it can also be applied to various cooling systems.

[Brief explanation of drawings]

FIG. 1 is a refrigerant circuit diagram of one embodiment of the invention, FIGS. 2A and 2B are operation pattern diagrams of a four-way valve, and FIG. 3 is a refrigerant circuit diagram of another embodiment of the invention. 10... Outdoor unit as a condensing unit, 20A, 20B... Indoor unit as a cooling unit, 30... Operation switching unit,
31...Simultaneous, four-way switching valve for independent operation, 32A,
32B, 33A, 33B...branch line, 34
A, 34B...Capillary tube for simultaneous operation,
35A, 35B... Capillary tube for independent operation, 36A, 36B... Two-way solenoid valve, 37A, 3
7B...Liquid receiver.

Claims (1)

[Scope of utility model registration request] Two cooling units can be connected to one condensing unit, and two cooling units can be operated simultaneously or one can be operated independently to form a refrigeration cycle with the condensing unit. In the refrigeration system, a four-way valve for switching simultaneous or independent operation is inserted in the middle of the refrigerant piping path connecting the condensing unit and the evaporator of each cooling unit, and the first port of the four-way valve and the condensing A parallel refrigerant piping line connecting a second port and each of the evaporators and each having a capillary tube for simultaneous operation, and a third port and a parallel refrigerant pipe line each having a capillary tube for simultaneous operation. A refrigerant piping line provided with a capillary tube for individual operation, a two-way solenoid valve whose individual operation side is open, and a liquid receiver, which are provided in parallel with each other, is connected to the fourth port, each of the evaporators, and the condensing unit. and the middle of the low-pressure refrigerant piping connecting the accumulator, and during simultaneous operation, the first port and the second port, and the third port and the fourth port.
A refrigeration system characterized in that the first port and the third port and the second port and the fourth port communicate with each other during independent operation.