JPH05118678A - Room cooling and heating device - Google Patents

Abstract

PURPOSE:To prolong the service life of a refrigerant pump by a method wherein an auxiliary pump unit is provided between an indoor machine and an outdoor machine and a difference between a detected inlet pressure and a detected outlet pressure is operated to drive the refrigerant pump of the auxiliary pump unit and close a refrigerant bypass valve when the operated difference is higher than a predetermined value. CONSTITUTION:An auxiliary pump unit 27, constituted of the second four-way valve 22, the second refrigerant pump 23, the second refrigerant amount regulating tank 24, the refrigerant pump bypass 25 and the refrigerant pump bypass valve 26 of an utilizing side refrigerant cycle, is arranged on the half way between an indoor machine 12 and an outdoor machine 10. The control device 28 of an auxiliary pump unit 27 is provided while the inlet pressure and the outlet pressure of a first refrigerant pump 17 are detected by pressure sensors 18, 19 and detecting means 29, 30 respectively. A differential pressure detecting means 31 operates the difference of both pressures. When the pressure difference excesses a first predetermined value, the second refrigerant pump 23 is driven until the pressure difference becomes lower than a second predetermined value and the bypass valve 26 is closed. According to this method, the life of the first refrigerant pump 17 is elongated and properties, coping with a high lift and a long pipeline, are improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating / cooling device separated into a heat source side refrigerant cycle and a use side refrigerant cycle.

[0002]

2. Description of the Related Art A conventional cooling / heating apparatus separated into a heat source side refrigerant cycle and a use side refrigerant cycle is disclosed in, for example, Japanese Patent Laid-Open No.
No. 2,720,040.

A conventional air conditioner of this type will be described below with reference to the drawings. In FIG. 4, 1 is a compressor, 2 is a heat source side refrigerant cycle four-way valve that becomes a cooling cycle when OFF, 3 is a heat source side heat exchanger, 4 is a pressure reducing device, and 5 is a first auxiliary heat exchanger. Are connected to form a heat source side refrigerant cycle 6.

Reference numeral 7 denotes a second auxiliary heat exchanger, which is integrally formed with the first auxiliary heat exchanger 5 so as to exchange heat.

Reference numeral 8 is a refrigerant pump for delivering the refrigerant, and 9 is an OF.
It is a use-side refrigerant cycle four-way valve that becomes a cooling cycle at F, and these are housed in the outdoor unit 10. A heat exchanger 11 on the use side is housed in the indoor unit 12.

The second auxiliary heat exchanger 7, the refrigerant pump 8, the use side refrigerant cycle four-way valve 9, and the use side heat exchanger 11
Are connected in an annular shape to form a utilization side refrigerant cycle 13. Reference numeral 14 is a remote controller for setting cooling, heating, room temperature and the like.

Reference numeral 15 is a cooling / heating operation detecting means for detecting cooling or heating, and 16 is a compressor 1, a heat source side refrigerant cycle four-way valve 2, a refrigerant pump 8, and a use side refrigerant cycle four-way valve 9.
Is a device driving means for driving.

The operation of the cooling and heating device configured as described above will be described. During the cooling operation, in the heat source side refrigerant cycle 6, the high-temperature high-pressure gas from the compressor 1 passes through the heat source side refrigerant cycle four-way valve 2 which is turned off to radiate heat in the heat source side heat exchanger 3 to condense and liquefy it. Depressurized at 4, first
The heat source side refrigerant cycle four-way valve 2 that evaporates in the auxiliary heat exchanger 5
To reflux to compressor 1.

At this time, the second auxiliary heat exchanger 7 and the first auxiliary heat exchanger 5 of the use side refrigerant cycle 13 exchange heat, and the gas refrigerant in the use side refrigerant cycle 13 is cooled and liquefied.

The liquefied refrigerant is sent to the user side heat exchanger 11 through the user side refrigerant cycle four-way valve 9 and the refrigerant pump 8 which are in the OFF state, and is cooled and endothermic vaporized to be gasified to be used side. It will circulate through the second auxiliary heat exchanger 7 of the refrigerant cycle 13. Further, the heating mode is basically a reverse cycle of the cooling mode, and detailed description thereof will be omitted.

During heating operation, in the heat source side refrigerant cycle 6,
The high-temperature high-pressure gas from the compressor 1 passes through the heat-source-side refrigerant cycle four-way valve 2 that is ON, is radiatively condensed by the first auxiliary heat exchanger 5, decompressed by the decompression device 4, and absorbed by the heat-source-side heat exchanger 3. Evaporate and pass through the heat source side refrigerant cycle four-way valve 2 and compressor 1
To reflux.

At this time, the second auxiliary heat exchanger 7 and the first auxiliary heat exchanger 5 of the usage-side refrigerant cycle 13 exchange heat, and the liquid refrigerant in the usage-side refrigerant cycle 13 is overheated and gasified.

The gasified refrigerant is used by the heat exchanger 11 on the use side.
To the second auxiliary heat exchanger 7 of the usage-side refrigerant cycle 13 through the usage-side refrigerant cycle four-way valve 9 and the refrigerant pump 8 that are turned on to heat and liquefy the heat. Become.

[0014]

However, in the conventional structure, in the case of the high head and long piping, for example, when the height difference between the outdoor unit and the indoor unit is 100 m, the resistance due to the gravity of the liquid refrigerant is the first refrigerant pump. Since the capacity exceeds the capacity, the overload operation is performed in which the differential pressure of the first refrigerant pump exceeds the limit value. Therefore, there is a drawback that the life of the first refrigerant pump is shortened and the reliability of the cooling and heating device is reduced.

In view of the above problems, the present invention shortens the life of the first refrigerant pump by keeping the differential pressure of the first refrigerant pump of the utilization side refrigerant cycle within the limit value in the case of high head / long piping. It is an object of the present invention to provide a cooling and heating device that not only prevents the above, but also improves the high head and long piping.

[0016]

In order to solve the above-mentioned problems, the cooling and heating apparatus of the present invention has a use-side refrigerant cycle second four-way valve, a second refrigerant pump, and a second refrigerant in the middle of an indoor unit and the outdoor unit. An auxiliary pump unit consisting of a quantity adjustment tank, a refrigerant pump bypass, and a refrigerant pump bypass valve is provided.
The differential pressure between the inlet pressure detected by the inlet pressure detecting means and the outlet pressure detected by the outlet pressure detecting means is calculated by the differential pressure calculating means, and when the differential pressure exceeds the first predetermined value, the auxiliary pump unit driving means. The control device drives the second refrigerant pump and closes the refrigerant pump bypass valve until the differential pressure falls below a second predetermined value.

[0017]

In the cooling and heating apparatus of the present invention, when the differential pressure of the first refrigerant pump becomes equal to or higher than the limit value at the time of high head and long piping, the resistance of the liquid refrigerant due to the gravity becomes first by driving the auxiliary pump unit. It is possible to prevent the refrigerant pumping capacity from becoming higher than the capacity, and to keep the differential pressure of the first refrigerant pump below the limit value.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An air conditioner according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a cooling and heating apparatus according to an embodiment of the present invention. Here, the same components as those of the conventional example are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 1, 17 is a first refrigerant pump, 1
Reference numeral 8 is an inlet pressure sensor for detecting the inlet pressure of the first refrigerant pump 17, and 19 is an outlet pressure sensor for detecting the outlet pressure of the first refrigerant pump 17. Reference numeral 20 is a first four-way valve on the use side refrigerant cycle, and 21 is a first refrigerant amount adjusting tank. In addition, 22 is the second four-way valve on the utilization side refrigerant cycle, and 23
Is a second refrigerant pump, 24 is a second refrigerant amount adjusting tank, 25
Is a refrigerant pump bypass that bypasses the upstream side and the downstream side of the second refrigerant pump 23, and 26 is a refrigerant pump bypass valve, which constitutes an auxiliary pump unit 27. 28
Is a control device for controlling and operating the auxiliary pump unit 27.

FIG. 2 is a detailed view of the control device 26 of FIG. 1, showing the inlet pressure detecting means 29 for detecting the inlet pressure of the first refrigerant pump 17 with the pressure sensor 18, and the outlet pressure of the first refrigerant pump 17. The outlet pressure detecting means 30 detected by the outlet pressure sensor 19, the differential pressure calculating means 31 for calculating the differential pressure between the inlet pressure detecting means 29 and the outlet pressure detecting means 30, the second refrigerant pump 23 and the refrigerant pump bypass valve 26. It is composed of an auxiliary pump unit driving means 32 for driving.

The operation of the auxiliary pump unit 27 and its control unit 28 of the present embodiment will be described with reference to the flowchart of FIG. 3 for the cooling and heating apparatus of the present embodiment configured as described above.

In STEP 1, the inlet pressure detecting means 29 is used, for example, the inlet pressure sensor 18 to detect the first refrigerant pump 17
The inlet pressure P1 (MPa) of the first refrigerant pump 17 is detected by the outlet pressure sensor 19, and the outlet pressure sensor 19 detects the outlet pressure P2 (MPa) of the first refrigerant pump 17, for example.

In STEP 2, the differential pressure calculating means 31 calculates the differential pressure P2-P1 (MPa). Here, when the differential pressure exceeds the first predetermined value, that is, P2-P1> 0.5
If it is (MPa), it is judged that the auxiliary pump unit 27 needs to be driven, and the process proceeds to STEP3.
Move to P4.

In STEP 3, the auxiliary pump unit driving means 32 operates the second refrigerant pump 23 and closes the refrigerant pump bypass valve 26. This auxiliary pump unit 2
By driving No. 5, the differential pressure P of the first refrigerant pump 17
It is possible to reduce 1-P2 within the limit value and prevent the life of the refrigerant pump from being shortened.

In STEP 4, when the differential pressure falls below the second predetermined value, that is, when P1-P2 <0.2 (MPa), the process proceeds to STEP 5, and otherwise the process proceeds to STEP 6.

In STEP 5, the second refrigerant pump 23 is stopped and the refrigerant pump bypass valve 26 is opened.

STEP 6 is to maintain the current operation. In this way, the routines of STEP1 to STEP4 are repeated during the operation of the cooling and heating device.

As described above, in the middle of the indoor unit 12 and the outdoor unit 10, the user side refrigerant cycle second four-way valve 22, the second refrigerant pump 23, the second refrigerant amount adjusting tank 24, the refrigerant pump bypass 25, An auxiliary pump unit 27 including the refrigerant pump bypass valve 26 is provided, and the differential pressure between the inlet pressure detected by the inlet pressure detecting means 29 and the outlet pressure detected by the outlet pressure detecting means 30 is calculated by the differential pressure calculating means 31. However, when the differential pressure exceeds a predetermined value, the auxiliary pump unit drive means 32 causes the differential pressure to drop below the predetermined value, so that the refrigerant pump bypass valve 26 is closed to drive the second refrigerant pump 23. By providing 28, the differential pressure of the first refrigerant pump 17 can be kept within the limit value.
This has the effect of not only preventing the life of the first refrigerant pump 17 from being shortened, but also providing a cooling and heating apparatus that further improves the high head and long piping.

[0030]

As is apparent from the embodiments described above, the cooling and heating apparatus of the present invention has the use-side refrigerant cycle second four-way valve, the second refrigerant pump, and the second refrigerant amount adjustment in the middle of the indoor unit and the outdoor unit. An auxiliary pump unit including a tank, a refrigerant pump bypass, and a refrigerant pump bypass valve is provided, and the differential pressure between the inlet pressure detected by the inlet pressure detecting means and the outlet pressure detected by the outlet pressure detecting means is calculated by the differential pressure calculating means. When the differential pressure exceeds the first predetermined value, the auxiliary pump unit driving means drives the second refrigerant pump to close the refrigerant pump bypass valve until the differential pressure falls below the second predetermined value. It is characterized by having a control device.

Therefore, by driving the auxiliary pump unit at the time of high lift and long piping, it is possible to prevent the resistance due to the gravity of the liquid refrigerant from exceeding the capacity of the refrigerant pump and keep the differential pressure of the first refrigerant pump within the limit value. Can be kept. As a result, there is an effect that not only the life of the first refrigerant pump can be prevented from being shortened, but also a cooling and heating device can be provided in which the high head and long piping are further improved.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of an air conditioner according to an embodiment of the present invention.

FIG. 2 is a detailed block diagram of a control device according to an embodiment of the present invention.

FIG. 3 is an operation flowchart of a cooling and heating device showing an embodiment of the present invention.

FIG. 4 is a block configuration diagram of a conventional cooling and heating device.

[Explanation of Codes] 1 compressor 2 heat source side refrigerant cycle four-way valve 3 heat source side heat exchanger 4 pressure reducing device 5 first auxiliary heat exchanger 6 heat source side refrigerant cycle 7 second auxiliary heat exchanger 10 outdoor unit 11 use side heat Exchanger 12 Indoor unit 13 Usage-side refrigerant cycle 17 First refrigerant pump 20 Usage-side refrigerant cycle First four-way valve 21 First refrigerant amount adjustment tank 22 Usage-side refrigerant cycle Second four-way valve 23 Second refrigerant pump 24 Second refrigerant quantity Adjustment tank 25 Refrigerant pump bypass 26 Refrigerant pump bypass valve 27 Auxiliary pump unit 28 Control device 29 Inlet pressure detection means 30 Outlet pressure detection means 31 Differential pressure calculation means 32 Auxiliary pump unit drive means

Claims (1)

[Claims] 1. A heat source side refrigerant cycle comprising a compressor, a heat source side refrigerant cycle four-way valve, a heat source side heat exchanger, a pressure reducing device and a first auxiliary heat exchanger connected in an annular shape, and the first auxiliary heat exchanger. A second auxiliary heat exchanger which is integrally formed with and exchanges heat, a utilization side refrigerant cycle first four-way valve, a first refrigerant pump, a first refrigerant amount adjustment tank, a utilization side refrigerant cycle second four-way valve, a second refrigerant pump, A second refrigerant amount adjusting tank, a refrigerant pump bypass having a refrigerant pump bypass valve that bypasses the upstream side and the downstream side of the second refrigerant pump and closes when the second refrigerant pump is used, and a utilization side heat exchanger are connected in an annular shape. And a heat source side refrigerant cycle, the second auxiliary heat exchanger, the use side refrigerant cycle first four-way valve, a first refrigerant pump, a first
An outdoor unit composed of a refrigerant amount adjustment tank, an indoor unit composed of the usage side heat exchanger, the usage side refrigerant cycle second four-way valve, a second refrigerant pump,
Inlet pressure detection means for detecting the inlet pressure of the first refrigerant pump and the auxiliary pump unit which is composed of the second refrigerant amount adjusting tank, the refrigerant pump bypass, and the refrigerant pump bypass valve and is located between the indoor unit and the outdoor unit. And the first
Outlet pressure detection means for detecting the outlet pressure of the refrigerant pump,
A control device comprising: a differential pressure calculating means for calculating a differential pressure between the inlet pressure detecting means and the outlet pressure detecting means; and a second pump for pump and an auxiliary pump unit driving means for driving the refrigerant pump bypass valve. The control device includes the second refrigerant pump until the differential pressure calculated by the pressure calculation means exceeds a first predetermined value until the differential pressure falls below a second predetermined value by the auxiliary pump unit driving means. A cooling and heating device which is driven to close the refrigerant pump bypass valve.