JPH0771831A - Direct air-conditioning type heat pump device - Google Patents

Abstract

PURPOSE:To reduce construction cost by eliminating a high-pressure liquid receiver to greatly reduce filling amounts of refrigerant, thereby simplifying a system. CONSTITUTION:A low-pressure liquid receiver 2 is provided at an elevated spot and a liquid delivery port 2a thereof is connected to each air conditioner 1 and one end of an air heat exchanger 3 through a low-temperature liquid feed pipe 5, and a gas delivery port 2b of the receiver 2 is connected to each of the air conditioner 1, the other end of the heat exchanger 3, and a suction port of a compressor 4 through a low-temperature gas return pipe 7, and the delivery port of the compressore 4 is connected to each of the air conditioners 1 and one end of the exchanger 3 through a high-temperature gas feed pipe 8. Further, each of the air conditioners 1 and the other end of the exchanger 3 are connected to a refrigerant feed port 2c of the receiver 2 through a condensed liquid return pipe 6, and flow regulating valves 13a and 13b are respectively provided at connecting ends between each of the air conditioners 1 and exchanger 3, and the pipes 5, 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct air-conditioning type heat pump device applicable to air conditioning of a large building, and relates to a structure for eliminating a high pressure liquid receiver and reducing a refrigerant charge amount.

[0002]

2. Description of the Related Art As a direct air-conditioning heat pump, a direct air-conditioning heat pump device disclosed in Japanese Patent Publication No. 2-35213 is known. As shown in FIG. 2, this direct air-conditioning heat pump device has a compressor 31, a high-pressure receiver 32, and an expansion valve 33 at a low place, and a low-pressure receiver 35 at a place higher than an air conditioner 34, so Liquid outlet 3 of receiver
5a and each air conditioner 34 are connected by a low temperature liquid supply pipe 37, the gas outlet 35b of the low pressure receiver is connected by a low temperature gas return pipe 38 to each air conditioner 34 and the compressor 31, and the compressor 31
And the air heat exchanger 36 are connected via a motor-operated valve 42 by a high temperature gas supply pipe 39, and this high pressure gas supply pipe 39 is connected to each air conditioner 3
4, the high-pressure liquid receiver 32 and the air heat exchanger 36 are connected by the high-temperature liquid return pipe 40 via the motor-operated valve 43, and the high-temperature liquid return pipe 40 is connected to each air conditioner 34 to receive the high-pressure liquid reception liquid. The container 32 and the low-pressure liquid receiver 35 are connected by a liquid pipe 41 via an expansion valve 33.

The operation of this device is as follows. First, during the cooling cycle, the high-temperature high-pressure refrigerant gas compressed by the compressor 31 is guided to the air heat exchanger 36 through the high-temperature gas supply pipe 39, where heat is released to ambient air and condensed and liquefied. It becomes high-temperature high-pressure liquid and is stored in the high-pressure liquid receiver 32 through the high-temperature liquid return pipe 40. The high-temperature high-pressure liquid in the high-pressure liquid receiver 32 is decompressed by the expansion valve 33, becomes a low-temperature low-pressure gas-liquid two-phase flow, and is guided to the low-pressure liquid receiver 35 through the liquid pipe 41. The low temperature low pressure liquid in the low pressure receiver 35 is supplied to the low temperature liquid supply pipe 37.
Is sent to each of the air conditioners 34 through the head through the flow control valve 48.
The indoor air is cooled by the air conditioner 34, becomes low temperature low pressure gas, and passes through the low temperature gas return pipe 38 to the compressor 3
1 is sucked. At this time, regarding the open / closed state of the solenoid valves around the air conditioner 34, the solenoid valves 47 and 49 are opened and the solenoid valves 46 and 50 are opened.
Is closed. The low-temperature low-pressure gas in the low-pressure liquid receiver 35 is also sucked into the compressor 31 through the low-temperature gas return pipe 38.

Next, the heating cycle will be described. The high-temperature high-pressure refrigerant gas compressed by the compressor 31 is guided to each air conditioner 34 through the high-temperature gas supply pipe 39, where the indoor air is heated to become a high-temperature high-pressure liquid, and passes through the high-temperature liquid return pipe 40. It is stored in the high-pressure liquid receiver 32. The high-temperature high-pressure liquid in the high-pressure liquid receiver 32 is decompressed by the expansion valve 33, becomes a low-temperature low-pressure gas-liquid two-phase flow, and is guided to the low-pressure liquid receiver 35 through the liquid pipe 41. The low-temperature low-pressure liquid in the low-pressure receiver 35 is sent through the low-temperature liquid supply pipe 37 to the air heat exchanger 36 at a head, where heat is taken from the ambient air to become a low-temperature low-pressure gas and a low-temperature gas return pipe 38. And is sucked into the compressor 31 to complete the cycle.

[0005]

As shown in FIG. 2, the prior art requires a high temperature liquid return pipe 40 and a high pressure liquid receiver 32 to recover the condensate, and further the high temperature and high pressure liquid is used. In order to return the high pressure liquid receiver 32 to the high pressure liquid receiver 32 by a head, the high pressure liquid receiver 32 needs to be installed at a lower position than the air conditioner 34 and the air heat exchanger 36. As a result, the expansion valve 33 is installed in a low place, and the liquid pipe 41 connects the high pressure receiver 32 installed in a low place and the low pressure receiver 35 installed in a high place to the building from the bottom up. It will penetrate. That is, in the conventional system, the building has five refrigerant pipes vertically,
That is, the low temperature liquid supply pipe 37, the low temperature gas return pipe 38, the high temperature gas supply pipe 39, the high temperature liquid return pipe 40, and the liquid pipe 41 were passed. And the high-pressure receiver 32 was required.

It is an object of the present invention to solve the above problems and to realize a direct air-conditioning type heat pump device in which the high pressure receiver, the expansion valve, the high temperature liquid return pipe and the liquid pipe are eliminated and the refrigerant filling amount is reduced. To do.

[0007]

In order to achieve the above object, the direct air-conditioning heat pump device of the present invention has a low-pressure receiver installed at a high place, and a liquid outlet of this low-pressure receiver. Connect one end of each air conditioner and air heat exchanger with a cryogenic liquid supply pipe, and connect the gas outlet of the low pressure receiver, the other end of the air conditioner and air heat exchanger, and the suction port of the compressor with a cryogenic gas return pipe. Connect the discharge port of the compressor to one end of each air conditioner and air heat exchanger with a hot gas supply pipe, and connect the other end of each air conditioner and air heat exchanger to the refrigerant supply port of the low pressure receiver. Was connected by a condensate return pipe, and a flow control valve was provided at the connection end of each air conditioner and the air heat exchanger with the low temperature liquid supply pipe and the condensate return pipe.

[0008]

[Operation] The operation will be described by taking the cooling operation as an example. At this time, the air heat exchanger becomes a condenser, but the flow control valve provided at the connection between the air heat exchanger and the condensate return pipe keeps the degree of supercooling of the condensate at the outlet of the air heat exchanger constant. To work. The condensate return pipe is connected to the low-pressure receiver to form a low-pressure space.Therefore, the high-temperature high-pressure condensate exiting the air heat exchanger is decompressed by the flow control valve, and the low-temperature low-pressure gas-liquid two It becomes a phase flow and enters the low pressure receiver through the condensate return pipe. Therefore, in this device, the flow rate control valve plays the role of the expansion valve of the conventional system, and the condensate return pipe also serves as the high temperature liquid return pipe of the conventional system. In this way, the high pressure receiver, expansion valve, high temperature liquid return pipe and liquid pipe can be eliminated in this system.

The air conditioner works as a condenser during heating,
The operation is exactly the same as that of the air heat exchanger during cooling. Also, when the flow rate control valve operates as a supercooling degree control valve when the air heat exchanger or the air conditioner functions as a condenser, it is as described above, but when these function as evaporators, they are the same as in the conventional system. , Operates as a superheat control valve.

[0010]

EXAMPLE An example of the present invention will be described with reference to FIG. FIG. 1 is a circuit diagram showing the configuration of the present invention. 1 is a large number of air conditioners installed in the building, a low pressure receiver 2 and an air heat exchanger 3 are installed on the roof above the air conditioner 1, and a compressor 4 is installed in the machine room on the basement level. is set up. The liquid outlet 2a of the low pressure receiver 2 is connected to one end of each air conditioner 1 and the air heat exchanger 3 by the low temperature liquid supply pipe 5, and the gas outlet 2b of the low pressure receiver 2 and each air conditioner 1 are connected.
The other end of the air heat exchanger 3 and the suction port of the compressor 4 are connected by a low temperature gas return pipe 7, and the discharge port of the compressor 4 and the low temperature gas return pipe 7 of each air conditioner 1 and the air heat exchanger 3 are connected. Are connected by a high temperature gas supply pipe 8, and the connection ends of the air conditioner 1 and the air heat exchanger 3 with the low temperature liquid supply pipe 5 and the refrigerant supply port 2C of the low pressure liquid receiver 2 are connected with the condensate return pipe 6 Connected by. Further, solenoid valves 11a and 11 are provided at the connection portions of the air conditioners 1 and the air heat exchangers 3, the low temperature liquid supply pipe 5, the condensate return pipe 6, the low temperature gas return pipe 7, and the high temperature gas supply pipe 8, respectively.
b, 12a, 12b, 9a, 9b, 10a, 10b
The flow control valves 13a and 13b are attached to the connection ends of the low temperature liquid supply pipe 5 and the condensed liquid return pipe 6, the air conditioner 1 and the air heat exchanger 3, respectively. A pressure adjusting valve 14 is attached to the connection portion of the low temperature gas return pipe 7 with the gas outlet 2b of the low pressure receiver 2.

Next, the operation of the above embodiment will be described.
First, in the cooling operation, the high-temperature high-pressure refrigerant gas compressed by the compressor 4 reaches the air heat exchanger 3 serving as a condenser through the high-temperature gas supply pipe 8 and the electromagnetic valve 10b, and is condensed and liquefied there. It becomes a high temperature and high pressure liquid. The flow rate control valve 13 adjusts the opening degree of this high-temperature high-pressure liquid so that the degree of supercooling is set in advance. Then, the high-temperature high-pressure supercooled liquid is decompressed when passing through the flow rate control valve 13b, becomes a low-temperature low-pressure gas-liquid two-phase flow, and enters the low-pressure receiver 2 through the electromagnetic valve 12b and the condensate return pipe 6. . The low-temperature low-pressure liquid in the low-pressure liquid receiver 2 passes through the low-temperature liquid supply pipe 5, the solenoid valve 11a, and the flow rate control valve 13a, and the difference in pressure produced by the head and the pressure control valve 14 causes each air conditioner 1 to be an evaporator. Sent. The flow rate control valve 13a controls the refrigerant flow rate so that the refrigerant superheat degree at the outlet of the air conditioner becomes constant. The refrigerant gas discharged from the air conditioner 1 and the solenoid valve 9a is sucked into the compressor 4 through the low temperature gas return pipe 7 together with the low temperature low pressure gas in the low pressure receiver 2, and the cycle is completed. The pressure control valve 14 controls the pressure in the low pressure receiver 2 to the low temperature gas return pipe 7
The pressure is made slightly higher than the internal pressure to operate to compensate for the insufficient head difference between the low pressure receiver 2 and each air conditioner 1 and the air heat exchanger 3.

Next, the heating operation will be described. In the heating operation, the air conditioner 1 functions as a condenser, and the air heat exchanger 3 functions as an evaporator. The operation is the same as in the cooling operation. That is, the high-temperature high-pressure gas discharged from the compressor 4 is condensed in the air conditioner 1 and decompressed by the flow rate control valve 14a,
A low-temperature low-pressure gas-liquid two-phase flow enters the low-pressure receiver 2.
Then, the low-temperature low-pressure liquid in the low-pressure receiver 2 is evaporated in the air heat exchanger 3 to become a low-temperature low-pressure gas and returns to the compressor 4.

[0013]

Since the present invention is constructed as described above, it has the following effects. In the conventional direct air-conditioning type heat pump device, since the condensate is returned to the high-pressure receiver at the high pressure as it is, the high-pressure receiver is required, and the installation position is below each air conditioner and air heat exchanger. There was a need.
An expansion valve and a liquid pipe are required to send the high-temperature high-pressure liquid in the high-pressure receiver to low-temperature low-pressure and send it to the low-pressure receiver. Had to be properly controlled. As a result, five refrigerant pipes, namely a low temperature liquid supply pipe, a low temperature gas return pipe, a high temperature gas supply pipe, a high temperature liquid return pipe and a liquid pipe were passed through the building. Since the high-pressure receiver had a large amount of refrigerant, the amount of refrigerant filled was large.

According to the present invention, since the condensate is throttled by the flow control valve and directly returned to the low pressure receiver through the condensate return pipe, the high pressure receiver is not required. As a result, all the excess refrigerant in the device is collected in the low-pressure receiver, so that the liquid level control of the low-pressure receiver is not necessary and the refrigerant charge amount can be significantly reduced. The expansion valve and liquid pipe are no longer required, and the system is simpler and the construction cost can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention.

FIG. 2 is a circuit diagram showing an example of a conventional direct air conditioning heat pump device.

[Explanation of symbols]

 1 Air-conditioner 2 Low-pressure receiver 2a Liquid outlet of low-pressure receiver 2b Gas outlet of low-pressure receiver 2c Refrigerant supply port of low-pressure receiver 3 Air heat exchanger 4 Compressor 5 Low-temperature liquid supply pipe 6 Condensation Liquid return pipe 7 Low temperature gas return pipe 8 High temperature gas supply pipe 13a Flow rate adjustment valve 13b Flow rate adjustment valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Sato 2-13-1, Botan, Koto-ku, Tokyo Inside Maekawa Co., Ltd.

Claims (1)

[Claims] 1. A direct air-conditioning type heat pump device for cooling and heating by directly supplying a CFC-based refrigerant to a plurality of air conditioners installed in a plane and three-dimensionally, and installing a low pressure receiver at a high place, Connect the liquid outlet of the air conditioner and one end of each air conditioner and air heat exchanger with a low temperature liquid supply pipe, and the gas outlet of the low pressure receiver and the other end of each air conditioner and air heat exchanger and suction of the compressor. Connect the port with a low-temperature gas return pipe, connect the discharge port of the compressor with one end of each air conditioner and air heat exchanger with a hot gas supply pipe, and connect the other end of each air conditioner and air heat exchanger with a low pressure receiver. A feature is that the refrigerant supply port of the liquid container is connected with a condensate return pipe, and flow control valves are provided at the connection ends of the low-temperature liquid supply pipe of each air conditioner and the air heat exchanger and the condensate return pipe, respectively. Direct air conditioning type heat pump device.