JP2016102601A - Refrigeration cycle device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a time ranging from an energization of a device to a completion of defrosting and prevent a large amount of liquid refrigerant from flowing into a compressor.SOLUTION: There is provided an inner heat exchanger 15 for heat-exchanging between refrigerant flowed out of a water-refrigerant heat exchanger 12 and refrigerant flowed out of an evaporator 14 to heat the refrigerant flowed out of the evaporator 14. Further, when a request for operation of a compressor 11 is attained, a solenoid valve 16 is controlled in such a way that the refrigerant discharged out of the compressor 11 may flow to both an electric expansion valve 13 and a defrosting refrigerant flow passage 17 and the same time the compressor 11 is operated to defrost the evaporator 14.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a refrigeration cycle apparatus.

  Conventionally, a bypass pipe and a solenoid valve are provided between the compressor and the evaporator, and the solenoid valve is controlled so that the refrigerant discharged from the compressor is introduced into the evaporator through the bypass pipe when the evaporator is defrosted. There is something like that (see, for example, Patent Document 1). In this apparatus, the refrigerant discharged from the compressor flows into the evaporator, melts the frost of the evaporator, and returns to the compressor.

JP-A-5-296614

  In such an apparatus, if the evaporator is frosted at the time of starting up the apparatus, the efficiency is deteriorated. Therefore, it is preferable to start the defrosting of the evaporator immediately at the time of starting up the apparatus. However, in such an apparatus, after starting the apparatus, the refrigerant discharged from the compressor is sufficiently boosted to stabilize the state of the apparatus, and then the solenoid valve is opened to defrost the evaporator. It has become. For this reason, efficiency is low and it takes time to complete the defrosting. Moreover, since it takes time to complete the defrosting, there is a problem that wasteful power is consumed.

  It is possible to shorten the time until defrosting is completed if the device is started with the solenoid valve opened, but when the device is started with the solenoid valve opened, the refrigerant discharged from the compressor is reduced. The pressure hardly rises and a large amount of liquid refrigerant tends to flow into the inlet side of the compressor. In particular, immediately after startup of the apparatus, the pressure of the refrigerant discharged from the compressor is low, and a large amount of liquid refrigerant tends to flow into the inlet side of the compressor. As described above, if a large amount of liquid refrigerant flows into the inlet side of the compressor, it causes a reduction in the capacity of the apparatus and a failure of the compressor.

  The present invention has been made in view of the above problems, and an object of the present invention is to reduce the time from the start of the apparatus to the completion of defrosting and to prevent a large amount of liquid refrigerant from flowing into the compressor.

  In order to achieve the above-mentioned object, the invention according to claim 1, the compressor (11) that compresses and discharges the refrigerant, and heat-exchanges the refrigerant and the heat medium discharged from the compressor to heat the heat medium. Heat medium-refrigerant heat exchanger (12), pressure reducing means (13, 18) for reducing the pressure of the refrigerant flowing out of the heat medium-refrigerant heat exchanger, and an evaporator (evaporating the refrigerant reduced by the pressure reducing means) 14) and an internal heat exchanger (15) that heats the refrigerant that has flowed out of the heat medium-refrigerant heat exchanger and the refrigerant that has flowed out of the evaporator, and flows out of the evaporator and is sucked into the compressor A defrosting refrigerant flow path (17) for guiding a part of the refrigerant discharged from the compressor to the evaporator, an opening / closing device (16) for opening and closing the defrosting refrigerant flow path, and an operation request for the compressor If there is, the refrigerant discharged from the compressor flows into both the decompression means and the defrosting refrigerant flow path. A defrosting control means for defrosting the evaporator by operating the compressor to control the opening and closing device so that (S104 to S110), is characterized by comprising a.

  According to the above configuration, the internal heat exchanger that heats the refrigerant that flows out of the evaporator and is sucked into the compressor by exchanging heat between the refrigerant that flows out of the heat medium-refrigerant heat exchanger and the refrigerant that flows out of the evaporator. In addition, when there is a request for operating the compressor, the switching device is controlled so that the refrigerant discharged from the compressor flows through both the decompression means and the defrosting refrigerant flow path, and the compressor is operated to evaporate. Since the defrosting of the vessel is performed, it is possible to shorten the time from the start of the apparatus to the completion of the defrosting. Moreover, since the refrigerant flowing out of the evaporator and sucked into the compressor is heated by the internal heat exchanger, it is possible to prevent a large amount of liquid refrigerant from flowing into the compressor.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

It is a figure which shows the structure of the heat pump cycle apparatus which concerns on 1st Embodiment of this invention. It is a flowchart of the control apparatus of the heat pump cycle apparatus which concerns on 1st Embodiment of this invention. It is a flowchart of the control apparatus of the heat pump cycle apparatus which concerns on 2nd Embodiment of this invention. It is a figure which shows the structure of the heat pump cycle apparatus which concerns on 4th Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

(First embodiment)
The configuration of the heat pump cycle device according to the first embodiment of the present invention is shown in FIG. The heat pump cycle device 10 is a vapor compression refrigeration cycle device configured by sequentially connecting a compressor 11, a water-refrigerant heat exchanger 12, an electric expansion valve 13, an evaporator 14 and the like through refrigerant pipes. . Further, the heat pump cycle device 10 fulfills a function of directly or indirectly heating a heat medium such as hot water or hot water stored in the hot water storage tank 20.

  Further, the heat pump cycle device 10 employs carbon dioxide as a refrigerant, and the refrigerant pressure on the high pressure side of the cycle from the discharge port side of the compressor 11 to the inlet side of the electric expansion valve 13 is equal to or higher than the critical pressure of the refrigerant. This constitutes a supercritical refrigeration cycle.

  The compressor 11 sucks the refrigerant in the heat pump cycle device 10, compresses the refrigerant to a critical pressure or higher, and discharges the high-temperature and high-pressure refrigerant. In the present embodiment, an electric compressor that drives a fixed displacement type compression mechanism with a fixed discharge capacity by an electric motor is employed as the compressor 11. The operation (the number of rotations) of the electric motor of the compressor 11 is controlled by a control signal output from a control device described later.

  The water-refrigerant heat exchanger 12 heats hot water directly by exchanging heat between the refrigerant discharged from the compressor 11 and hot water. Hot water is a fluid to be heated by the heat pump cycle device 10, and is stored in the hot water storage tank 20 and then supplied to a kitchen or a bath. Furthermore, the hot water supply of the present embodiment also functions as a heat medium that moves the heat generated in the heat pump cycle device 10 to the hot water supply stored in the hot water storage tank 20.

  The electric expansion valve 13 is a decompression unit that decompresses the refrigerant flowing out from the refrigerant passage 12 a of the water-refrigerant heat exchanger 12. Specifically, the electric expansion valve 13 is a variable throttle mechanism that includes a valve body that can change the throttle opening degree and an electric actuator that changes the throttle opening degree of the valve body. . Further, the operation of the electric actuator is controlled by a control signal output from the control device.

  The evaporator 14 evaporates the refrigerant decompressed by the electric expansion valve 13 by exchanging heat with the outside air. An internal heat exchanger 15 is connected to the refrigerant outlet side of the evaporator 14. The refrigerant flowing out of the evaporator 14 passes through the internal heat exchanger 15 and then flows into the suction port of the compressor 11.

  The internal heat exchanger 15 heats the refrigerant flowing out of the evaporator 14 by exchanging heat between the refrigerant flowing out of the refrigerant passage 12 a of the water-refrigerant heat exchanger 12 and the refrigerant flowing out of the evaporator 14.

  The defrosting refrigerant channel 17 is a refrigerant channel that guides the refrigerant discharged from the compressor 11 to the evaporator 14.

  The electromagnetic valve 16 is an opening / closing device that opens and closes the defrosting refrigerant flow path 17. The electromagnetic valve 16 has its throttle opening controlled by a control signal output from the control device.

  In addition, each component apparatus 11-17 of the heat pump cycle apparatus 10 is accommodated in one housing | casing, or is accommodated in one frame structure, and is comprised integrally as a heat pump unit.

  Next, the hot water storage tank 20 will be described. The hot water storage tank 20 is formed of a metal having excellent corrosion resistance (for example, stainless steel), and has a heat insulating structure in which the outer periphery is covered with a heat insulating material or a vacuum heat insulating structure with a double tank, and keeps hot hot water hot for a long time. It is a hot water tank that can. The hot water storage tank 20 is also arranged outside the room. Hot water stored in the hot water storage tank 20 is used for hot water supply and heating.

  The hot water storage tank 20 is connected to the water passage 12 b of the water-refrigerant heat exchanger 12 of the heat pump cycle device 10 by a water circulation circuit 21. The water circulation circuit 21 is a water circulation circuit that circulates hot water between the hot water storage tank 20 and the water-refrigerant heat exchanger 12. The water circulation circuit 21 is provided with a water circulation pump 22 for circulating hot water.

  The water circulation pump 22 sucks hot water flowing out from a hot water outlet provided on the lower side of the hot water storage tank 20 and pumps the hot water into the water passage 12 b of the water-refrigerant heat exchanger 12. It is. Further, the operation (rotation speed) of the water circulation pump 22 is controlled by a control signal output from the control device.

  Therefore, when the water circulation pump 22 is operated, hot water is supplied from the hot water outlet provided on the lower side of the hot water storage tank 20 → the water circulation pump 22 → the water passage 12 b of the water-refrigerant heat exchanger 12 → the upper side of the hot water storage tank 20. It circulates in the order of the hot water inlet provided in the. Thereby, the hot water heated by the water-refrigerant heat exchanger 12 flows out to the upper side of the hot water storage tank 20, and the temperature distribution in which the temperature of the hot water is decreased from the upper side to the lower side in the hot water storage tank 20. Occurs.

  Next, an outline of a control device (not shown) of this embodiment will be described. The control device is configured as a computer including a CPU, a ROM, a RAM, an I / O, and the like, and the CPU performs various processes according to a program stored in the ROM.

  An operation panel (not shown) is connected to the control device. The operation panel is provided with an operation switch for outputting an operation request for requesting the operation of the heat pump cycle device 10, a temperature setting switch for setting a hot water supply temperature, and the like, and an operation signal of the switch is input to the control device. . In addition, a detection signal is input to the control device from a surface temperature sensor 14 a that detects the surface temperature of the evaporator 14.

  Next, processing of the control device of the heat pump cycle device 10 will be described. FIG. 2 shows a flowchart of the control device. When the control device receives an operation request for requesting an operation output from the operation panel in response to a user operation, the control device performs the process in FIG. In addition, each control step in the flowchart of each drawing comprises the various function implementation | achievement means which a control apparatus has.

  First, information for determining whether or not the evaporator 14 is frosted is acquired to determine whether or not the evaporator 14 is frosted (S100). Specifically, the control device acquires a detection signal output from the surface temperature sensor 14a, and based on this detection signal, the surface temperature of the evaporator 14 is a predetermined frosting reference temperature (for example, −10 ° C.). It is determined whether or not: In addition, when the surface temperature of the evaporator 14 is equal to or lower than a predetermined frosting reference temperature, it is determined that the evaporator 14 is frosting.

  Here, when the surface temperature of the evaporator 14 is higher than the predetermined frosting reference temperature, the determination in S100 is NO, and the heat pump is normally started (S200). Specifically, the control device reads the operation signal of the operation panel and the detection signal detected by the control sensor group described above, and connects to the output side of the control device based on the read operation signal and detection signal. The control states (specifically, control signals or control voltages output to the various control target devices) of the various control target devices are determined.

  Here, the control signal output to the solenoid valve 16 is determined so that the throttle opening of the solenoid valve 16 is fully closed. The control signal output to the compressor 11 is determined based on a hot water supply temperature setting signal from the operation panel. The control signal output to the electric actuator of the electric expansion valve 13 is determined so that the high-pressure side refrigerant pressure of the heat pump cycle device 10 becomes the target high pressure. The control voltage output to the water circulation pump 22 is determined using a feedback control method or the like. Then, the control device outputs the control signal and the control voltage determined as described above to various devices to be controlled.

  After that, the control device performs a control routine such as reading the above detection signal and operation signal, determining the control state of various control target devices, and outputting control voltages and control signals to the various control target devices at predetermined control cycles. The normal operation is performed (S300).

  Further, the control device determines whether or not the operation switch on the operation panel is turned off and an operation stop request of the heat pump cycle device 10 is received (S114). Here, normal operation is performed until an operation stop request for the heat pump cycle device 10 is received.

  When the operation switch on the operation panel is turned OFF and the operation stop request for the heat pump cycle device 10 is received, the control device stops the operation of the heat pump (S116) and ends the process.

  In addition, after the operation of the heat pump is stopped in this manner, for example, when a certain period of time has elapsed and the control device receives an operation request for requesting an operation output from the operation panel, the control device It is determined whether 14 is frosting (S100). Here, when the surface temperature of the evaporator 14 is equal to or lower than a predetermined frosting reference temperature and the determination in S100 is YES, the solenoid valve 16 is controlled to open the throttle opening of the solenoid valve 16. (S104). That is, the solenoid valve 16 is controlled so that the refrigerant discharged from the compressor 11 flows through both the heat medium-refrigerant heat exchanger 12 and the defrosting refrigerant flow path 17. Specifically, the solenoid valve 16 is controlled so that the throttle opening of the solenoid valve 16 is fully opened.

  Next, the electric expansion valve 13 is controlled to open the throttle opening of the valve body of the electric expansion valve 13 (S106). In addition, about the control signal output to the electric actuator of the electric expansion valve 13, it determines so that the high pressure side refrigerant | coolant pressure of the heat pump cycle apparatus 10 may become target high pressure.

  Next, the heat pump is activated while defrosting (S108). Specifically, the control device reads the operation signal of the operation panel and the detection signal detected by the control sensor group described above, and connects to the output side of the control device based on the read operation signal and detection signal. The control states (specifically, control signals or control voltages output to the various control target devices) of the various control target devices are determined.

  Here, the control signal output to the compressor 11 is determined based on a hot water supply temperature setting signal or the like from the operation panel. The control voltage output to the water circulation pump 22 is determined using a feedback control method or the like. Then, the control device outputs the control signal and the control voltage determined as described above to various devices to be controlled.

  Thereby, the high-temperature and high-pressure refrigerant discharged from the compressor 11 flows not only in the heat medium-refrigerant heat exchanger 12 but also in the defrosting refrigerant flow path 17 and is introduced into the evaporator 14. In this way, the evaporator 14 is defrosted. In addition, the refrigerant that has flowed out of the evaporator 14 is heated by the internal heat exchanger 15, becomes a gas, and is sucked into the compressor 11.

  Next, it is determined whether or not defrosting is completed (S112). Specifically, the control device determines whether or not the surface temperature of the evaporator 14 is equal to or higher than a predetermined defrosting end reference temperature (for example, −5 ° C.) based on a detection signal output from the surface temperature sensor 14a. Determine. When the surface temperature of the evaporator 14 is equal to or higher than the defrosting end reference temperature, it is determined that the defrosting of the evaporator 14 is completed.

  Here, when the surface temperature of the evaporator 14 is lower than the defrosting end reference temperature, the determination in S112 is NO, and the determination in S112 is repeatedly performed. During this time, defrosting of the evaporator 14 is continued.

  When the surface temperature of the evaporator 14 becomes equal to or higher than the defrosting end reference temperature, the determination in S112 is YES and normal operation is performed (S300).

  According to the above configuration, the refrigerant that flows out of the water-refrigerant heat exchanger 12 and the refrigerant that flows out of the evaporator 14 exchange heat and heats the refrigerant that flows out of the evaporator 14 and is sucked into the compressor 11. A heat exchanger 15 is provided. Further, when there is a request for operation of the compressor 11, the electromagnetic valve 16 so that the refrigerant discharged from the compressor 11 flows through both the electric expansion valve 13 and the defrosting refrigerant flow path 17. Since the compressor 11 is operated and the evaporator 14 is defrosted, the time from the start of the apparatus to the completion of the defrosting can be shortened. Further, since the refrigerant that flows out of the evaporator 14 and is sucked into the compressor 11 is heated by the internal heat exchanger 15, a large amount of refrigerant sucked into the compressor 11 can be made into a gas. It is also possible to prevent a large amount of liquid refrigerant from flowing into 11.

  Further, the control device acquires information for determining whether or not the evaporator 14 is frosted, determines whether or not the evaporator 14 is frosted, and the evaporator 14 is frosted. When it is determined that the evaporator 14 is defrosted, the evaporator is defrosted, and therefore the evaporator can be defrosted only when the evaporator 14 is frosted.

(Second Embodiment)
The flowchart of the control apparatus of the heat pump cycle apparatus which concerns on 2nd Embodiment of this invention is shown in FIG. The flowchart shown in FIG. 3 is different from the flowchart shown in FIG. 2 in the processing after YES is determined in S100. When the control device receives an operation request for requesting an operation output from the operation panel in response to a user operation, the control device performs the process in FIG.

  First, it is determined whether or not the evaporator 14 is frosted (S100). If it is determined that the evaporator 14 is frosted, then the solenoid valve 16 opens the throttle opening of the solenoid valve 16. 16 is controlled (S104). Specifically, the solenoid valve 16 is controlled so that the throttle opening of the solenoid valve 16 is fully opened.

  Next, the electric expansion valve 13 is controlled to open the throttle opening of the valve body of the electric expansion valve 13 (S106). In addition, about the control signal output to the electric actuator of the electric expansion valve 13, it determines so that the high pressure side refrigerant | coolant pressure of the heat pump cycle apparatus 10 may become target high pressure.

  Next, the compressor 11 is operated (S108). Here, the control signal output to the compressor 11 is determined based on a hot water supply temperature setting signal or the like from the operation panel. Here, the water circulation pump 22 is also operated.

  Next, the electric expansion valve 13 is controlled so as to gradually reduce the throttle opening of the valve body of the electric expansion valve 13 (S110). Specifically, the electric expansion valve 13 is controlled so that the valve body of the electric expansion valve 13 is fully closed after a predetermined time has elapsed, and the process proceeds to S112.

  When the throttle opening of the valve body of the electric expansion valve 13 is suddenly reduced after the compressor 11 is operated, the refrigerant flowing out of the evaporator 14 is not sufficiently heated by the internal heat exchanger 15 and the compressor 11 May be inhaled.

  However, as described above, after the compressor 11 is operated, the electric expansion valve 13 is controlled so as to gradually reduce the throttle opening degree of the electric expansion valve 13, so that the outflow from the evaporator 14 occurs. The refrigerant thus cooled can be sufficiently heated by the internal heat exchanger 15 and sucked into the compressor 11. Further, after the compressor 11 is operated, the electric expansion valve 13 is controlled so as to gradually reduce the throttle opening of the valve body of the electric expansion valve 13, thereby flowing toward the defrosting refrigerant flow path 17 side. Since the amount of the refrigerant can be gradually increased, the defrosting time can be further shortened.

  In this embodiment, the effect produced from the configuration common to the first embodiment can be obtained in the same manner as in the first embodiment.

(Third embodiment)
FIG. 4 shows the configuration of the heat pump cycle device according to the third embodiment of the present invention. The heat pump cycle device 10 of the present embodiment includes an ejector 18 and an accumulator 19 instead of the expansion valve 13 in the heat pump cycle device 10 of the first embodiment.

  The ejector 18 is a decompression unit that decompresses and expands the refrigerant that has flowed out of the internal heat exchanger 15. The refrigerant decompressed by the ejector 18 flows into the accumulator 19.

  The accumulator 19 is a gas-liquid separator that is disposed on the downstream side of the ejector 18 and separates the gas-liquid refrigerant flowing out of the ejector 18 and accumulates excess liquid-phase refrigerant in the cycle.

  The liquid-phase refrigerant separated by the accumulator 19 flows into the evaporator 14. The vapor phase refrigerant separated by the accumulator 19 is heated by the internal heat exchanger 15 and then sucked into the compressor 11.

  When the solenoid valve 16 is opened, the refrigerant discharged from the compressor 11 flows into the evaporator 14 through the defrosting refrigerant flow path 17.

  The control device of the present embodiment controls the electromagnetic valve 16 so that the refrigerant discharged from the compressor 11 flows through both the ejector 18 and the defrosting refrigerant flow path 17 when there is an operation request of the compressor 11. The compressor 11 is operated to defrost the evaporator 14.

  The heat pump cycle device 10 of the present invention may be applied to an ejector type refrigeration cycle that employs the ejector 18 as a decompression unit as in the present embodiment.

  In the present embodiment, the effects produced from the configuration common to the first embodiment described above can be obtained as in the first embodiment.

  In addition, although this embodiment is embodiment based on 1st Embodiment, it is also possible to combine this embodiment with the above-mentioned 2nd Embodiment.

(Other embodiments)
In the above embodiment, it is determined whether or not the evaporator 14 is frosted based on the temperature detected by the surface temperature sensor 14 a that detects the surface temperature of the evaporator 14. A gas temperature detection sensor for detecting the temperature of the refrigerant gas flowing out from the evaporator 14 may be provided, and it may be determined whether or not the evaporator 14 is frosted based on the temperature detected by the gas temperature detection sensor. .

  Further, the heat pump cycle device 10 of the first embodiment acquires information for determining whether or not the evaporator 14 is frosted, acquires the surface temperature of the evaporator 14, and the evaporator 14 It is determined whether or not the evaporator 14 is frosted based on the surface temperature of the refrigerant, but a refrigerant temperature sensor for detecting the temperature of the refrigerant flowing out of the evaporator 14 is provided, and based on a detection signal of the refrigerant temperature sensor You may make it determine whether the evaporator 14 is frosting. Further, a fan (not shown) is used to blow the evaporator 14 to detect the temperature of the air downstream of the evaporator 14, and based on this temperature, whether the evaporator 14 is frosted or not is determined. You may make it determine.

  Moreover, in the said embodiment, although the structure provided with the water-refrigerant heat exchanger 12 which heat-exchanges the hot water by heat-exchanging the refrigerant | coolant discharged from the compressor 11 and hot water supply was shown, water-refrigerant heat exchange is shown. It is good also as a structure provided with the heat medium-refrigerant heat exchanger which replaces with the apparatus 12 and heats a heat medium by heat-exchanging the refrigerant | coolant discharged from the compressor 11, and heat media other than water.

  In the first embodiment, the electric expansion valve 13 is used as the pressure reducing means. However, a mechanical expansion valve can be used as the pressure reducing means.

  In each of the above-described embodiments, the heat pump cycle in which the compressor 11 is used is a supercritical refrigeration cycle, but may be a subcritical refrigeration cycle in which the high-pressure refrigerant discharged from the compressor 11 does not exceed the critical pressure of the refrigerant. . Moreover, the refrigerant | coolant compressed with the compressor 11 is not restricted to a carbon dioxide, For example, you may employ | adopt a fluorocarbon refrigerant | coolant.

  In addition, this invention is not limited to above-described embodiment, In the range described in the claim, it can change suitably. Further, the above embodiments are not irrelevant to each other, and can be combined as appropriate unless the combination is clearly impossible. Further, in each of the above embodiments, when numerical values such as the number, numerical value, quantity, range, etc. of the constituent elements of the embodiment are mentioned, it is clearly limited to a specific number when clearly indicated as essential and in principle. The number is not limited to the specific number except for the case. In each of the above embodiments, when referring to the material, shape, positional relationship, etc. of the constituent elements, etc., unless otherwise specified, or in principle limited to a specific material, shape, positional relationship, etc. The material, shape, positional relationship, etc. are not limited.

  The correspondence relationship between the configuration of the above embodiment and the configuration of the claims will be described. S104 to S110 correspond to a defrost control unit, and S100 corresponds to a frost determination unit.

DESCRIPTION OF SYMBOLS 10 Heat pump cycle apparatus 11 Compressor 12 Water-refrigerant heat exchanger 13 Electric expansion valve 14 Evaporator 15 Internal heat exchanger 16 Solenoid valve 17 Defrosting refrigerant flow path 18 Ejector 19 Accumulator

Claims (4)

A compressor (11) for compressing and discharging the refrigerant;
A heat medium-refrigerant heat exchanger (12) for heating the heat medium by exchanging heat between the refrigerant discharged from the compressor and the heat medium;
Decompression means (13, 18) for decompressing the refrigerant flowing out of the heat medium-refrigerant heat exchanger;
An evaporator (14) for evaporating the refrigerant decompressed by the decompression means;
An internal heat exchanger (15) that heat-exchanges the refrigerant that has flowed out of the heat medium-refrigerant heat exchanger and the refrigerant that has flowed out of the evaporator to flow out of the evaporator and sucked into the compressor When,
A refrigerant flow path for defrost (17) for guiding a part of the refrigerant discharged from the compressor to the evaporator;
An opening and closing device (16) for opening and closing the defrosting refrigerant flow path;
When there is a request for operation of the compressor, the compressor is controlled and the compression is performed so that the refrigerant discharged from the compressor flows through both the heat medium-refrigerant heat exchanger and the defrosting refrigerant flow path. A heat pump cycle device comprising: a defrost control means (S104 to S110) for operating the machine to defrost the evaporator. The pressure reducing means is an electric expansion valve capable of changing the throttle opening of the valve body,
The defrost control means controls the electric expansion valve to open the throttle opening of the valve body, and then operates the compressor to gradually reduce the throttle opening of the valve body while operating the compressor. The heat pump cycle device according to claim 1, wherein the heat expansion cycle valve is controlled.   The heat pump cycle device according to claim 1, wherein the decompression unit is configured by an ejector. Frost determination means (S100) for acquiring information for determining whether or not the evaporator is frosted and determining whether or not the evaporator is frosted,
4. The defrosting control unit according to claim 1, wherein the defrosting control unit defrosts the evaporator when the frosting determination unit determines that the evaporator is frosted. 5. The heat pump cycle apparatus as described in one.

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