JP2014074557A - Refrigeration cycle device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigeration cycle device capable of efficient operation with an optimal amount of a cooling medium for an outdoor temperature even when the same changes.SOLUTION: A refrigeration cycle device comprises: a cooling medium circuit 6 with a compressor 1, a heat radiator 2, an expansive valve, and an evaporator 4 connected in this order; an internal heat exchanger 5 which exchanges heat between the heat radiator 2 and the expansive valve 3 and between the evaporator 4 and the compressor 1; a bypass circuit 15 which connects the internal heat exchanger 5 respectively with the expansive valve 3 and the evaporator 4; cooling medium adjustment means (16 and 17) which is arranged on the bypass circuit 15; and outdoor temperature detection means 7 which detects an outdoor temperature. The refrigeration cycle device controls operation of the cooling medium adjustment means (16 and 17) on the basis of the temperature detected by the outdoor temperature detection means 7.

Description

  The present invention relates to a refrigeration cycle apparatus.

  Conventionally, for example, in a refrigeration cycle apparatus mounted on a heat pump water heater, the refrigerant is enclosed in the refrigeration cycle apparatus, and the entire amount is circulated in a closed circuit and controlled to perform boiling (for example, patents) Reference 1).

  Such a conventional refrigerant cycle device will be described. FIG. 3 shows an example in which an internal heat exchanger for exchanging heat between the high-pressure side refrigerant and the low-pressure side refrigerant of the refrigeration cycle is added to the refrigeration cycle apparatus described in Patent Document 1.

  As shown in FIG. 3, the refrigerant cycle device includes a compressor 1, a radiator 2, an expansion valve 3, an evaporator 4, a space between the radiator 2 and the expansion valve 3, the evaporator 4, the A refrigerant circuit 6 is formed by the internal heat exchanger 5 installed between the compressors 1, the compressor 1, the radiator 2, the expansion valve 3, the evaporator 4, and the internal heat exchanger 5. .

  Also, an outside air temperature detecting means 7 installed in the evaporator 4 for detecting the outside air temperature, a discharge temperature detecting means 8 for detecting the discharge temperature of the compressor 1, and an incoming water for supplying low-temperature water to the radiator 2. A pipe 9, a hot water supply pipe 10 for supplying high-temperature water from the radiator 2, a water circuit 11 constituted by the radiator 2, the incoming water pipe 9, and the outgoing hot water pipe 10, and an upstream side of the water circuit 11 A circulating pump 12 installed in the hot water, a hot water temperature detecting means 13 installed in the hot water piping 10, and a control device (not shown) for controlling the refrigerant circuit 6 and the water circuit 11.

JP 2011-158193 A

  However, the conventional refrigeration cycle apparatus is generally disposed in an outdoor unit, and is configured such that the entire amount of refrigerant circulates in a closed circuit regardless of the operating condition (spring, summer, autumn and winter).

  For this reason, there has been a problem that high-efficiency operation with an optimal refrigerant amount according to the outside air temperature cannot always be performed.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object of the present invention is to provide a refrigeration cycle apparatus that can perform an efficient operation with an optimum refrigerant amount even when the outside air temperature fluctuates.

In order to solve the above-described conventional problems, the refrigeration cycle apparatus of the present invention includes a refrigerant circuit in which a compressor, a radiator, an expansion valve, and an evaporator are connected in order, and between the radiator and the expansion valve and the evaporation. An internal heat exchanger that exchanges heat between the compressor, the compressor, a bypass circuit that connects the internal heat exchanger, the expansion valve, the evaporator, and the internal heat exchanger; The refrigerant amount adjusting means disposed on the bypass circuit, an outside air temperature detecting means for detecting the outside air temperature, and a control device, and based on the detected temperature of the outside air temperature detecting means, The operation is controlled.

  Thereby, even if the outside air temperature fluctuates, it is possible to provide a refrigeration cycle apparatus that can perform an efficient operation with an optimum refrigerant amount corresponding to the fluctuation.

  ADVANTAGE OF THE INVENTION According to this invention, even if outside temperature fluctuates, the refrigerating-cycle apparatus which can operate efficiently with the optimal refrigerant | coolant amount according to it can be provided.

Configuration diagram of a refrigeration cycle apparatus according to Embodiment 1 of the present invention. Diagram showing outside air temperature control of the refrigeration cycle apparatus Configuration diagram of conventional refrigeration cycle equipment

  In the first invention, heat exchange is performed between a refrigerant circuit in which a compressor, a radiator, an expansion valve, and an evaporator are sequentially connected, and between the radiator and the expansion valve, and between the evaporator and the compressor. An internal heat exchanger to perform, a bypass circuit connecting the internal heat exchanger, between the expansion valve and the evaporator, and between the internal heat exchanger, and refrigerant amount adjustment disposed on the bypass circuit Means, an outside temperature detecting means for detecting the outside air temperature, and a control device, and the operation of the refrigerant amount adjusting means is controlled based on the temperature detected by the outside air temperature detecting means. It is.

  Thereby, even if the outside air temperature fluctuates, it is possible to provide a refrigeration cycle apparatus that can perform an efficient operation with an optimum refrigerant amount corresponding to the fluctuation.

  According to a second aspect of the present invention, a plurality of refrigerant amount adjusting means are disposed on the bypass circuit, and the control device controls operations of the plurality of refrigerant amount adjusting means based on the temperature detected by the outside air temperature detecting means. This is a refrigeration cycle apparatus.

  Thereby, in the case of excessive refrigerant, the plurality of refrigerant amount adjusting means are fully closed, so that the refrigerant can be confined between the plurality of refrigerant amount adjusting means, and the refrigerant amount in the refrigerant circuit is reduced. Can do.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a diagram showing a configuration of a refrigeration cycle apparatus mounted on a heat pump water heater in Embodiment 1 of the present invention.

  In FIG. 1, a refrigeration cycle apparatus includes a refrigerant circuit 6 in which a compressor 1, a radiator 2 that is a water refrigerant heat exchanger, an expansion valve 3, and an evaporator 4 that is an air refrigerant heat exchanger are sequentially connected. And an internal heat exchanger 5 that exchanges heat between the high-pressure refrigerant between the radiator 2 and the expansion valve 3 and the low-pressure refrigerant between the evaporator 4 and the compressor 1. .

  Also, an outside air temperature detecting means 7 that is installed in the evaporator 4 and detects the outside air temperature, a discharge temperature detecting means 8 that detects the discharge temperature of the compressor 1, and a control device 14 that controls the operation of the equipment. I have.

Further, the water inlet pipe 9 for supplying low-temperature water to the radiator 2, the hot water outlet pipe 10 for supplying high-temperature water from the radiator 2, and the water circuit by the radiator 2, the inlet pipe 9, and the outlet pipe 10. 11 is formed.

  A circulating pump 12 is disposed upstream of the water circuit 11, and a tapping temperature detecting means 13 is disposed in the tapping piping 10.

  Further, a bypass circuit 15 for connecting the internal heat exchanger 5 and the expansion valve 3 and between the evaporator 4 and the internal heat exchanger 5 is provided, and the upstream side on the bypass circuit 15 is provided. The first refrigerant amount adjusting means 16 is disposed on the downstream side of the bypass circuit 15, and the second refrigerant amount adjusting means 17 is disposed downstream of the bypass circuit 15.

  FIG. 2 is a diagram showing that section division (A to E) is provided according to the outside air temperature.

  About the refrigerating-cycle apparatus of the heat pump water heater configured as mentioned above, the operation | movement and an effect | action are demonstrated below.

  A basic operation will be described with reference to FIG. At the start of boiling, the high-temperature refrigerant discharged from the compressor 1 is heat-exchanged with the low-temperature water supplied from the inlet pipe 9 of the water circuit 11 by the radiator 2 and then radiated by the internal heat exchanger 5. Is done.

  Subsequently, the low-temperature refrigerant decompressed by the expansion valve 3 is absorbed by the evaporator 4 and the internal heat exchanger 5, returned to the compressor 1, and compressed again. As a result, hot water is supplied to the hot water supply pipe 10.

  The refrigerant in the refrigeration cycle apparatus of the heat pump water heater is sealed in the refrigeration cycle apparatus of the outdoor unit, and the entire amount is circulated in a closed circuit and controlled to perform boiling.

  For this reason, for example, if the amount of refrigerant is filled so as to be optimal under the intermediate condition that is the average outside air temperature, the refrigerant becomes excessive under the winter condition, and the refrigerant is sucked into the compressor 1 in a wet state without sufficiently exchanging heat in the evaporator 4. , Efficiency will deteriorate.

  Further, under summer conditions, the refrigerant becomes insufficient, and the refrigerant is sucked into the compressor 1 in a state where the degree of heating is too high, so that the discharge temperature rises and the efficiency deteriorates.

  As shown in FIG. 1, the refrigeration cycle apparatus of the present invention is a bypass that connects between the internal heat exchanger 5 and the expansion valve 3 and between the evaporator 4 and the internal heat exchanger 5. A circuit 15; first refrigerant amount adjusting means 16 installed on the upstream side of the bypass circuit 15; and second refrigerant amount adjusting means 17 installed on the downstream side of the bypass circuit 15. .

  At the start of boiling, the first refrigerant amount adjusting unit 16 and the second refrigerant amount adjusting unit 17 are fully opened. If the refrigerant is excessive as in winter conditions, the second refrigerant amount adjusting unit 17 is fully closed first. Then, by fully closing the first refrigerant amount adjusting unit 16, the refrigerant can be confined between the first refrigerant amount adjusting unit 16 and the second refrigerant amount adjusting unit 17. The amount of refrigerant can be reduced.

  If it is desired to further reduce the refrigerant amount in this state, the first refrigerant amount adjusting means 16 is fully opened again and then fully closed. When it is desired to increase the refrigerant in the refrigerant circuit 6, the appropriate amount of refrigerant can be supplied into the refrigeration cycle by opening the second refrigerant amount adjusting means 17 by a certain amount and fully closing again after a certain time.

  Here, in order to determine the optimum amount of refrigerant, the target discharge temperature Td, the target frequency H, and the target expansion valve opening V are determined according to the outside air temperature Te, the hot water temperature Tout, and the incoming water temperature Tin. Such data is acquired by experiments in advance.

  Further, as shown in FIG. 2, the sections are divided according to the outside air temperature (for example, A to E). It is assumed that the outside air temperature is in the section A on the first day of operation.

  First, the first refrigerant quantity adjusting means 16 and the second refrigerant quantity adjusting means 17 are fully opened to start the operation. Stable operation is performed at the incoming water temperature Tin (A) at that time, the target hot water temperature Tout (A) determined by learning control, the target discharge temperature Td (A) acquired as data determined in advance, and the target frequency H (A). .

  At that time, it is assumed that the opening degree of the expansion valve becomes V1. On the second day, when there is a difference from the target expansion valve opening V (A) acquired as data in advance, the first refrigerant amount adjusting means and the second refrigerant amount adjusting means are set so that V1 = V (A). By controlling the amount of refrigerant, the optimum refrigeration cycle is achieved. Assume that the outside air temperature section has changed after the third day (A to B as an example in this case).

  Stable operation is performed at the incoming water temperature Tin (B) at that time, the target hot water temperature Tout (B) determined by learning control, the target discharge temperature Td (B) acquired as data determined in advance, and the target frequency H (B). .

  At this time, it is assumed that the opening degree of the expansion valve becomes V2. On the fourth day, when there is a difference from the target expansion valve opening V (B) acquired as data in advance, the first refrigerant amount adjusting means 16 and the second refrigerant amount adjusting means so that V2 = V (B). The refrigerant quantity is adjusted by controlling 17 to obtain an optimum refrigeration cycle.

  In general, since the refrigeration cycle apparatus is operated by effectively using inexpensive late-night power, the operation time of midnight is controlled to be long.

  For this reason, when the refrigerant amount is adjusted at the time of boiling in the midnight time zone, the refrigeration cycle can be stabilized for a long time, the refrigerant amount can be adjusted with high accuracy, and high efficiency can be achieved.

  However, since hot water is generally stored in a hot water tank, the temperature of the incoming water rises at the completion of boiling, and the refrigeration cycle becomes unstable. Is desirable.

  As described above, according to the present invention, since the amount of refrigerant is optimized in accordance with the change in the outside air temperature, an efficient operation can be performed even if the outside air temperature changes.

  As described above, since the refrigeration cycle apparatus according to the present invention can adjust the amount of refrigerant according to changes in the outside air temperature and can always perform an efficient operation, an air conditioner or a water heater equipped with the refrigeration cycle apparatus. Applicable to etc.

DESCRIPTION OF SYMBOLS 1 Compressor 2 Radiator 3 Expansion valve 4 Evaporator 5 Internal heat exchanger 6 Refrigerant circuit 7 Outside air temperature detection means 14 Control device 15 Bypass circuit 16 First refrigerant quantity adjustment means 17 Second refrigerant quantity adjustment means

Claims (2)

A refrigerant circuit in which a compressor, a radiator, an expansion valve, and an evaporator are sequentially connected, and an internal heat exchanger that performs heat exchange between the radiator and the expansion valve and between the evaporator and the compressor. A bypass circuit connecting the internal heat exchanger, the expansion valve and the evaporator, and the internal heat exchanger, a refrigerant amount adjusting means disposed on the bypass circuit, and an outside air temperature. An refrigeration cycle apparatus comprising: an outside temperature detecting means for detecting; and a control device, wherein the operation of the refrigerant amount adjusting means is controlled based on a temperature detected by the outside air temperature detecting means. A plurality of refrigerant quantity adjusting means are disposed on the bypass circuit, and the control device controls operations of the plurality of refrigerant quantity adjusting means based on the detected temperature of the outside air temperature detecting means. The refrigeration cycle apparatus according to claim 1.