WO2004010060A1 - Refrigerating cycle - Google Patents

Abstract

A refrigerating cycle which provides refrigerant circulation quantities corresponding to seasons, which can avoid overheat operation or wet operation, which does not require the use of a flow adjusting valve or the like, and which can be constructed at low costs. In this refrigerating cycle, a refrigerant delivered from a compressor (15) is caused to flow back to the compressor (15) successively through a gas cooler (16), a pressure reducing mechanism (17), and an evaporator (18). A refrigerant passage (22) and a refrigerant regulation vessel (30) which are disposed between the pressure reducing mechanism (17) and the evaporator (18) are interconnected through a connection passage (31). The refrigerant regulation vessel (30) is disposed in a temperature environment which changes dependent on the outside air temperature.

Description

 Description Refrigeration cycle technical field

 The present invention relates to a refrigeration cycle, for example, a refrigeration cycle that can be used for a heat source unit of a heat pump water heater. Background art

 As shown in FIG. 6, the heat pump water heater generally includes a tank unit 51 having a hot water storage tank 50 and a heat source unit 53 having a refrigeration cycle 52. The refrigeration cycle 52 is configured by connecting a compressor 54, a water heat exchanger (condenser) 55, an expansion valve 57, and an evaporator 58 in this order. The tank unit 51 includes the hot water storage tank 50 and a circulation path 59, and a water circulation pump 60 and a heat exchange path 61 are interposed in the circulation path 59. In this case, the heat exchange path 61 is constituted by a water heat exchanger 55.

In the above device, when the compressor 54 is driven and the pump 60 is driven (operated), the stored water (hot water) flows out from the intake port provided at the bottom of the hot water storage tank 50 into the circulation path 59. This flows through the heat exchange path 61. At this time, the hot water is heated (boiled) by the water heat exchanger 55 and returned to the upper portion of the hot water storage tank 50 from the hot water inlet. With this, high-temperature hot water is stored in the hot water storage tank 50. Conventionally, refrigerants such as dichlorodifluoromethane (R-12) and chlorodifluoromethane (R-22) have been used as refrigerants in the refrigeration cycle. However, due to problems such as environmental pollution, alternative refrigerants such as 1,1,1,1,2-tetrahydrofluoretane (R-134a) have been used. However, R_134a still has problems such as high global warming ability. In recent years, it has been recommended to use natural refrigerants that do not have such problems. It is known that a supercritical refrigerant such as carbon dioxide is useful as the natural refrigerant. However, in the above-described apparatus, changes in the outside air temperature cause load fluctuations on the water heat exchanger (gas cooler) side and the evaporator side, and the amount of circulated refrigerant differs every season. That is, as shown in Fig. 3, when the outside air temperature is high (high outside air), the cycle is like I, and when the outside air temperature is low (low outside air), the cycle is like 、. In), the density of the refrigerant in the evaporator 58 becomes larger than in winter (at low outside air). For this reason, it is difficult to operate with the optimal refrigerant amount for each season, and in summer, the circulation amount tends to be insufficient, resulting in excessive overheating, and in winter, the circulation amount tends to be excessive. The operation was wet, which may have reduced the reliability of the compressor.

 For this reason, as shown in FIG. 5, a refrigerant regulating container 65 is provided on the high pressure side, and a flow regulating valve is provided.

By adjusting 66, the amount of refrigerant in the refrigerant adjustment container (receiver) 65 may be increased or decreased to obtain a refrigerant circulation amount according to the outside air temperature. In this case, on the high-pressure side, a bypass circuit 67 is provided which branches off at a position downstream of the branch portion, and the receiver 65 is provided in the bypass circuit 67. A flow control valve 66 is provided at the outlet side of 65. That is, the bypass circuit 67 includes a first passage 68 branched from the upstream side of the water heat exchanger 55 and connected to the receiver 65, and a first passage 68 derived from the receiver 65. And a second passage 69 that joins the gas cooler 55 at a downstream side of the branching part of the second passage. The above-mentioned regulating valve 66 is interposed in the second passage 69. Further, a refrigerant passage 70 connecting the expansion valve 57 and the evaporator 58 passes through the inside of the receiver 65.

 Therefore, in the refrigeration cycle shown in FIG. 5, heat exchange is performed between the high-pressure refrigerant flowing into the receiver 65 via the bypass circuit 67 and the low-pressure refrigerant flowing through the refrigerant passage 70. Then, by adjusting the opening degree of the adjusting valve 66, the flow rate of the refrigerant passing through the receiver 65 is adjusted, and the temperature of the refrigerant in the receiver 65 is adjusted. In other words, by controlling the opening degree of the flow control valve 66, the required refrigerant temperature can be maintained, and the receiver 65 內 can have an appropriate refrigerant capacity, and the refrigerant circulation amount in this circuit can be reduced. The optimal amount can be used.

However, in a refrigeration cycle as shown in FIG. 5, as described above, the flow control valve 66 must be used, which increases the cost. Gas cooling on the high pressure side Since the bypass circuit 67 is provided in the middle of the cooler 55, the circuit configuration becomes complicated, it is difficult to manufacture, and the cost is further increased. In addition, since a part of the coolant circulating in the gas cooler 55 is bypassed, heat loss may occur and the heating capacity may be impaired. Disclosure of the invention

 The present invention has been made in order to solve the above-mentioned conventional drawbacks. The purpose of the present invention is to provide a refrigerant circulation amount according to each season, thereby avoiding overheating operation and wet operation. Another object of the present invention is to provide a refrigeration cycle that can be configured at low cost without using a flow control valve or the like.

 Therefore, a refrigeration cycle of the present invention is a refrigeration cycle in which refrigerant discharged from a compressor is returned to the compressor through a gas cooler, a decompression mechanism, and an evaporator in order. The refrigerant adjustment container is connected to a refrigerant passage between the container and the refrigerant via a connection passage, and the refrigerant adjustment container is arranged in a temperature environment that changes depending on the outside air temperature.

 In this refrigeration cycle, the refrigerant passage between the decompression mechanism and the evaporator and the refrigerant adjustment container are connected via the connection passage, so that the inside of the refrigerant adjustment container is provided between the decompression mechanism and the evaporator. Refrigerant (gas refrigerant) is introduced. The refrigerant adjustment container is placed in a temperature environment that changes depending on the outside air temperature. Therefore, for example, since the outside air is hot in summer, the refrigerant adjustment container is kept at a high temperature side, the amount of refrigerant stored in the refrigerant adjustment container decreases, and the refrigerant circulation amount in the circulation path of the refrigeration cycle decreases. Can be added. In addition, since the outside air is cold in winter, the refrigerant adjustment container is kept at a low temperature, the amount of refrigerant stored in the refrigerant adjustment container increases, and the amount of refrigerant circulating in the circulation path of the refrigeration cycle is reduced. Can be done. That is, by placing the refrigerant adjustment container in a temperature environment that changes depending on the outside air temperature, the amount of refrigerant stored in the refrigerant adjustment container can be increased or decreased to achieve a refrigerant circulation amount according to the outside air temperature. Monkey

For this reason, the refrigerant can be circulated with the amount of refrigerant corresponding to each season, and it is possible to prevent an excessive overheating operation or a wet operation. Moreover, the amount of circulating refrigerant varies depending on the outside air temperature without providing a bypass circuit or the like in which a regulating valve is interposed. Can be adjusted according to the temperature environment.

 The refrigeration cycle of one embodiment is characterized in that the temperature environment that changes depending on the outside air temperature is formed by a refrigerant ranging from the evaporator outlet to the compressor inlet.

 In the refrigeration cycle of the above embodiment, the refrigerant ranging from the evaporator outlet to the compressor inlet changes according to the outside air temperature. Therefore, a temperature environment that changes depending on the outside air temperature can be stably formed by the refrigerant, and the amount of the circulated refrigerant corresponding to the outside air temperature can be ensured.

 In one embodiment, the refrigerant adjustment container is attached to a refrigerant pipe extending from the evaporator outlet to the compressor suction port, and the refrigerant in the refrigerant pipe and the refrigerant in the refrigerant adjustment container are heated. It is characterized by being exchanged.

 In the refrigeration cycle of the above embodiment, since the refrigerant adjustment container is attached to the refrigerant pipe extending from the evaporator outlet to the compressor intake, the reliability of heat exchange between the refrigerant in the refrigerant pipe and the refrigerant in the refrigerant adjustment container is reduced. The refrigerant circulation rate is high, and the refrigerant circulation amount can be stably set according to the outside air temperature.

 The refrigeration cycle of one embodiment is characterized in that, in a refrigerant passage between the decompression mechanism and the evaporator, a throttle is provided on the evaporator side from a connection portion of the connection passage.

 In the refrigeration cycle of the above embodiment, by providing the throttle, an optimal suction superheat degree can be provided.

 The refrigeration cycle of one embodiment is characterized in that the refrigerant adjustment container is arranged so as to be exposed to the outside air.

 In the refrigeration cycle of the above embodiment, since the refrigerant adjustment container is exposed to the outside air, the refrigerant in the refrigerant adjustment container is warmed or cooled by the outside air. In other words, with a simple configuration, the amount of refrigerant in the refrigerant adjustment container increases and decreases according to the outside air temperature, and the amount of refrigerant circulated according to each season.

 The refrigeration cycle of one embodiment is characterized in that the refrigerant adjustment container is arranged in an air passage formed by a fan attached to the evaporator.

In the refrigeration cycle of the above embodiment, the refrigerant adjustment container is provided with a fan attached to the evaporator. The temperature of the refrigerant adjustment container can be adjusted by this wind, since it is arranged in the wind passage generated by the above.

 In one embodiment, the refrigeration cycle is characterized in that the refrigerant adjustment container is arranged on the leeward side downstream of the evaporator.

 In the refrigeration cycle of the above embodiment, the refrigerant adjustment container is arranged downstream of the evaporator on the leeward side, which is preferable in terms of heat exchange, and the temperature of the refrigerant adjustment container can be surely adjusted.

 The refrigeration cycle of one embodiment is characterized in that the temperature environment that changes depending on the outside air temperature is configured by heating or cooling the refrigerant adjustment container with a Peltier element or the like.

 In the refrigeration cycle of the above embodiment, the refrigerant adjustment container can be heated or cooled by a Peltier element or the like, so that the refrigerant in the refrigerant adjustment container can be reliably increased or decreased according to the outside air temperature. The refrigerant circulation amount can be adjusted stably according to the season.

 The refrigeration cycle of one embodiment is characterized in that the refrigerant adjustment container is arranged to exchange heat with water whose temperature changes depending on the outside air temperature.

 In the refrigeration cycle of the above embodiment, the temperature of the refrigerant adjustment container is adjusted by water whose temperature depends on the outside air. That is, the amount of refrigerant in the refrigerant adjustment container increases and decreases according to the outside air temperature, and the amount of refrigerant circulated according to each season.

 In one embodiment, a refrigeration cycle includes a refrigerant passage between the decompression mechanism and the evaporator, wherein a throttle is provided on the evaporator side of a connection portion of the connection passage, and a refrigerant in the refrigerant adjustment container is provided. And heat exchange between the refrigerant and the refrigerant in the vicinity of the inlet of the evaporator on the downstream side of the throttle. Further, the refrigerant adjustment container is provided with a heater H for adjusting the amount of refrigerant.

 In the refrigeration cycle of the above embodiment, the refrigerant in the refrigerant adjustment container exchanges heat with the low-temperature refrigerant immediately after passing through the throttle, so that the heat exchange can be reliably performed. Since a heater for adjusting the amount of refrigerant is provided, the temperature of the refrigerant adjustment container can be adjusted according to the outside air temperature by the heater.

The refrigeration cycle of one embodiment is characterized in that the high pressure side operates at supercritical pressure. ing.

 In the refrigeration cycle of the above embodiment, since the high pressure side operates at a supercritical pressure, a supercritical refrigerant used in a supercritical state is used as a refrigerant, and a refrigeration cycle that is friendly to the global environment. Further, according to the refrigeration cycle using a supercritical refrigerant, the pressure on the high pressure side increases, so that the advantage of providing the refrigerant adjustment container on the low pressure side can be fully utilized, and the operation of the above embodiment is particularly effective. Can be demonstrated. BRIEF DESCRIPTION OF THE FIGURES

 FIG. 1 is a simplified diagram showing an embodiment of the refrigeration cycle of the present invention.

 FIG. 2 is a Mollier diagram of the refrigeration cycle.

 FIG. 3 is a Mollier diagram of a conventional refrigeration cycle.

 FIG. 4 is a simplified view of a main part showing another embodiment of the refrigeration cycle of the present invention. FIG. 5 is a simplified diagram showing a comparative example of a refrigeration cycle.

 FIG. 6 is a simplified diagram of a conventional refrigeration cycle. BEST MODE FOR CARRYING OUT THE INVENTION

 Specific embodiments of the refrigeration cycle of the present invention will be described in detail with reference to the drawings. Figure 1 shows a simplified diagram of a heat pump water heater using this refrigeration cycle. This heat pump water heater has a tank unit 1 and a heat source unit 2, and heats water (hot water) in tank unit 1 with heat source unit 2. Is what you do. The tank unit 1 has a hot water storage tank 3, and the hot water stored in the hot water storage tank 3 is supplied to a bathtub or the like (not shown). That is, the hot water storage tank 3 is provided with a water supply port 5 on a bottom wall thereof and a tap hole 6 on an upper wall thereof. Then, city water (tap water) is supplied from the water supply port 5 to the hot water storage tank 3, and high-temperature hot water is supplied from the water supply port 6. In addition, the hot water storage tank 3 has a water inlet 7 at the bottom wall and a hot water inlet 8 at the top of the side wall (peripheral wall), and the water inlet 7 and the hot water inlet 8 pass through the circulation path 9. Connected. The circulation path 9 is provided with a water circulation pump 10 and a heat exchange path 11.

Next, the heat source unit 2 includes the refrigeration cycle R according to this embodiment. The freezing cycle R consists of a compressor 15, a water heat exchanger (gas cooler) 16, which constitutes the heat exchange path 11, a pressure reducing mechanism (electric expansion valve) 17, and an air heat exchanger (evaporator). 1) and 8 are connected in order. That is, the discharge port of the compressor 15 and the gas cooler 16 are connected through the refrigerant passage 20, the gas cooler 16 and the electric expansion valve 1 are connected through the refrigerant passage 21, The expansion valve 17 and the evaporator 18 are connected by a refrigerant passage 22, and the evaporator 18 and the compressor 15 are connected by a refrigerant passage 24 provided with an accumulator 23. As the refrigerant, for example, carbon dioxide gas (C 0 ₂ ) whose high pressure side is used at a supercritical pressure is used. The gas cooler as the water heat exchanger 16 has a function of cooling the high-temperature and high-pressure supercritical refrigerant compressed by the compressor 15. The refrigerant passage 20 is provided with an HPS 25 as a pressure protection switch and a pressure sensor 26. Further, the evaporator 18 is provided with a fan 40 for adjusting the capacity.

 Further, the refrigeration cycle R includes a liquid-gas heat exchanger 27 for cooling the high-pressure refrigerant flowing out of the gas cooler 16. In this case, the liquid-gas heat exchanger 27 has, for example, a double-pipe structure, in which a first passage 28 through which the refrigerant from the gas cooler 16 passes, and a refrigerant from the evaporator 18. A second passage 29 passing therethrough. That is, the first passage 28 constitutes a part of the refrigerant passage 21 connecting the gas cooler 16 and the electric expansion valve 17, and the second passage 29 constitutes the evaporator 18 and the compressor 1. A part of the refrigerant passage 24 that connects to the refrigerant passage 5 is formed. Therefore, heat is exchanged between the high-pressure and high-temperature refrigerant passing through the first passage 28 and the low-pressure and low-temperature refrigerant passing through the second passage 29, and supercools the refrigerant from the gas cooler 16. Also, the refrigerant entering the accumulator 23 can be heated to prevent wet compression of the compressor 15.

Further, in the refrigeration cycle R, the refrigerant adjustment container 30 is a refrigerant pipe extending from the outlet of the evaporator to the inlet of the compressor, and more specifically, the liquid gas heat exchanger 2. 7 between the second passage 29 and the accumulator 23). Therefore, the refrigerant adjustment container 30 comes into contact with the refrigerant passage 24, and heat exchange between the refrigerant in the refrigerant adjustment container 30 and the refrigerant in the refrigerant passage 24 is enabled. Further, a connection passage 31 is connected to the refrigerant adjustment container 30. That is, the connection passage 3] is connected to the refrigerant passage 22 (a refrigerant passage between the pressure reducing mechanism 17 and the evaporator 18), It connects the container 30. Therefore, the refrigerant (gas refrigerant) of the refrigeration cycle R is drawn out from between the decompression mechanism 17 and the evaporator 18 and stored in the refrigerant adjustment container 30 as a liquid refrigerant. The capacity of the refrigerant adjustment container 30 is determined by the cycle (compressor 15 → gas cooler 16 → decompression mechanism 17 → evaporator 18 → compressor 15 → circulation path through which the refrigerant circulates) About 1/10 of the total capacity (for example, about 300 to 400 cc).

 Then, in the refrigerant passage 22 between the pressure reducing mechanism 17 and the evaporator 18, a throttle 33 is provided on the evaporator 18 side from the connection portion 32 (point A) of the connection passage 31. I have. It should be noted that as the throttle 33, a force capable of using a fixed throttle such as a capillary tube or the like can be used as well as an electric expansion valve or the like. Further, as the throttle 33, for example, when the outside air temperature is 7 ° C and the refrigeration cycle has a heating capacity of 450 OW, a throttle having a suction superheat of 3 to 5 ° C is selected. Is preferred. By the way, this heat pump water heater has a temperature sensor (input water thermistor) 34 that detects the temperature of the circulation path 9 on the upstream side of the heat exchange path 11, and the temperature sensor on the downstream side of the heat exchange path 11 of the circulation path 9. Temperature sensor (outlet hot water thermistor) 35 that detects the temperature, temperature sensor (air heat exchange thermistor) 36 that detects the temperature of the evaporator 18, temperature sensor (the discharge pipe) that detects the discharge temperature of the compressor 15 Thermistor) 37 and a temperature sensor (outside air temperature thermistor) 38 that detects the outside air temperature are provided. Then, data (detected temperature) from these sensors is input to a control unit (not shown) (not shown) of the heat pump water heater, and various controls are performed based on the data. Done.

 That is, during operation of the heat pump water heater, for example, the temperature of the discharge pipe is detected by the discharge pipe thermistor 37, and the opening of the electric expansion valve 17 is adjusted so that the discharge pipe temperature becomes the target discharge pipe temperature. It can be adjusted (controlled). If the temperature of the water input thermistor 34 is equal to or higher than a predetermined temperature (for example, 60 ° C.), it is determined that the hot water in the hot water storage tank 3 is boiling, and the operation is stopped. Based on the temperature, the operating frequency of the compressor 15 can be controlled to adjust the hot water heating capacity (boiling capacity) and the like.

Next, the operation of the heat pump water heater (boiler operation) will be described. Pressure The compressor 15 is driven and the water circulation pump 10 is driven (operated). Then, the stored water (hot water) flows out of the water intake port 7 provided at the bottom of the hot water storage tank 3 and flows through the heat exchange path 11 of the circulation path 9. Further, the refrigerant discharged from the compressor 15 is returned to the compressor 15 via the gas cooler 16, the pressure reducing mechanism 17, and the evaporator 18 in order. Therefore, the water flowing through the heat exchange path 11 of the circulation path 9 is heated (boiled) by the water heat exchanger which is the gas cooler 16, and is returned from the hot water inlet 8 to the upper part of the hot water storage tank 3. You. Then, by continuing such an operation, hot water is stored in the hot water storage tank 3. In the current electricity tariff system, the unit price of electricity at night is set lower than that of daytime, so it is preferable to perform this operation during the late night hours when the cost is low to reduce costs.

 The Mollier diagram for this operation is shown in Figure 2. That is, in this refrigeration cycle, the high-pressure refrigerant in the state 1 is discharged from the compressor 15 and the high-pressure refrigerant is introduced into the gas cooler 16 (water heat exchanger). The gas cooler 16 exchanges heat with water passing through the heat exchange path 11. As a result, the water passing through the heat exchange path 11 is heated (boiled). Then, due to this heat exchange, the high-pressure refrigerant radiates heat to the water, and its enthalpy drops from 1 to 2. The high-pressure refrigerant in these two states is sent to the low-pressure mechanism 17 (expansion valve). The high-pressure refrigerant is depressurized to the point A by the pressure reducing mechanism 17, and further reduced to the state of 3 by the throttle 33. Then, the low-pressure refrigerant is introduced into the evaporator 18. In the evaporator 18, the low-pressure refrigerant exchanges heat with air. Due to this heat exchange, the low-pressure refrigerant absorbs heat and evaporates. That is, the enthalpy increases from 3 to 4, and the low-pressure refrigerant in this 4 state is sent to the compressor 15.

In this case, the refrigerant at the connection point 32 (point A) of the refrigerant passage 22 between the pressure reducing mechanism 17 and the evaporator 18 and the connection passage 31 flows from the evaporator outlet to the compressor inlet. And heat is exchanged with the refrigerant between the second passage 29 of the liquid-gas heat exchanger 27 and the accumulator 23 (point B). For this reason, if the temperature at the point B rises in accordance with the outside air, the temperature of the refrigerant regulating container 30 also rises, and the refrigerant storage amount decreases, and the temperature at the point B rises in accordance with the outside air. If the temperature decreases, the temperature in the refrigerant adjustment container 30 also decreases, and the amount of stored refrigerant increases. And it is shown by the broken line m) in Fig. 2. As described above, when the temperature difference between the points A and B disappears, the refrigerant storage amount in the refrigerant adjustment container 30 does not change, and the refrigerant circulates with a constant refrigerant circulation amount. Thus, in the refrigeration cycle R, the temperature at the point A and the temperature at the point B are almost equal. On the other hand, since the throttle 33 is provided, as shown in Fig. 2, the temperature at point B is obtained by adding the temperature corresponding to the pressure drop of this throttle 33 to the evaporation temperature (at point A). Temperature), a constant superheat (S) commensurate with the pressure drop can be obtained, and efficient operation is possible.

 By the way, the refrigerant pipe (refrigerant passage 24) from the evaporator outlet to the compressor inlet is affected by the outside air temperature, and in summer when the outside air temperature is high, it is higher than in winter when the outside air temperature is low. is there. Therefore, as shown in Fig. 3, when the outside air temperature is high (high outside air), a cycle like I occurs, and when the outside air temperature is low (low outside air temperature), a cycle like と な り occurs. At the time of temperature), the density inside the evaporator 18 is higher than in winter (at low outside temperature). Therefore, there is a large difference in the amount of refrigerant in the evaporator 18 between the high outside temperature and the low outside temperature. And the amount of circulating refrigerant was large at low outside air temperatures, despite the small amount of circulating refrigerant.

However, by providing the refrigerant adjustment container 30 and the connection passage 31, since the outside air has a high temperature in summer, the refrigerant adjustment container 30 is kept on the high temperature side and stored in the refrigerant adjustment container 30. As a result, the amount of refrigerant to be cooled is reduced, and the amount of refrigerant circulated in the circulation path of the refrigeration cycle can be increased. In winter, since the outside air is at a low temperature, the refrigerant adjustment container 30 is kept at a low temperature, the amount of refrigerant stored in the refrigerant adjustment container 30 increases, and the refrigerant circulation amount in the circulation path of the refrigeration cycle. Can be reduced. That is, by placing the refrigerant adjustment container 30 in a temperature environment that changes depending on the outside air temperature, the amount of refrigerant in the refrigerant adjustment container 30 is increased or decreased to obtain a refrigerant circulation amount according to the outside air temperature. be able to. For this reason, it is possible to circulate the refrigerant with the amount of refrigerant according to each season, and it is possible to prevent an excessive overheating operation or a wet operation. By arranging the refrigerant adjustment container 30 in a temperature environment that changes depending on the outside air temperature, the circulation amount according to the outside air temperature becomes natural as described above, The operation can be performed with the circulation amount according to the outside air temperature for each operation, and it is possible to prevent overheating operation and wet operation. Therefore, if the refrigerant adjustment container 30 is not provided in the refrigerant passage 24 or the like and is placed in another temperature environment that changes depending on the outside air temperature, the operation is performed with the circulation amount according to the outside air temperature. It is possible.

 Further, in the above-described embodiment, the refrigerant in the refrigerant passage (refrigerant pipe) 24 and the refrigerant in the refrigerant adjustment container 30 are heated by attaching the refrigerant adjustment container 30 to the refrigerant passage 24. Although it is exchanged, as shown in FIG. 4, the refrigerant adjustment container 30 may be arranged along a pipe between the throttle 33 and the evaporator 18. That is, heat exchange between the refrigerant in the refrigerant adjustment container 30 and the refrigerant near the inlet of the evaporator 18 downstream of the throttle 33 is enabled. In this case, the refrigerant adjustment container 30 is provided with a heater H for adjusting the amount of the refrigerant.

 With the configuration as shown in FIG. 4, the refrigerant in the refrigerant adjustment container 30 exchanges heat with the low-temperature refrigerant immediately after passing through the throttle 33, so that the heat exchange can be reliably performed. Since the refrigerant adjustment container 30 is provided with a heater H for adjusting the amount of refrigerant, the heater H can adjust the temperature of the refrigerant adjustment container 30. For this reason, the refrigeration cycle can be reliably operated with the refrigerant circulation amount corresponding to each season. That is, in this case, a temperature environment that changes depending on the outside air temperature is formed by heat exchange with the low-temperature refrigerant and heating of the heater H.

Other methods for placing the device under a temperature environment that varies depending on the outside air temperature include the following. For example, the refrigerant adjustment container 30 is simply arranged at a position exposed to the outside air (for example, outside the casing in which the frozen cycle is stored). In this case, if the refrigerant adjustment container 30 is exposed to the outside air, the refrigerant adjustment container 30 is heated or cooled according to the temperature of the outside air. Further, since the evaporator 18 is provided with a fan 4 °, the refrigerant adjusting container 30 is arranged in an air passage formed by the fan 40. In this case, either upstream of the evaporator 18 or downstream of the evaporator 18. Also in this case, the temperature in the air passage depends on the outside air. In particular, for heat exchange, it is preferable to arrange the refrigerant regulating container 30 on the leeward side downstream of the evaporator 18. Further, a Peltier element or the like may be used. Here, the ぺ ^ / che element means that when current flows through the contacts of different types of conductors (or semiconductors), This element can exhibit the Peltier effect, which is a phenomenon that generates or absorbs heat in addition to the heat generated. Therefore, in this case, the outside air temperature is detected (detected) by the outside air temperature thermistor 38, and the Peltier element is caused to generate heat * by the refrigerant adjustment container 30 based on the outside air temperature. Further, the refrigerant adjustment container 30 may be configured to exchange heat with water. In this case, the cooling water can be composed of city water (tap water), water flowing out from the intake port 7 of the hot water storage tank 3 to the circulation path 9, and the like. Water

When using (tap water), it is only necessary to attach a refrigerant regulating container 30 to the water pipe that supplies tap water to the hot water storage tank 3.When using water from the circulation path 9, water is taken from the hot water storage tank 3. What is necessary is just to attach the refrigerant adjustment container 30 to the pipe between the port 7 and the inlet of the gas cooler 16.

 Although the specific embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and can be implemented with various modifications within the scope of the present invention. For example, when the refrigerant regulating container 30 is disposed in the refrigerant conduit 24 extending from the evaporator outlet to the compressor inlet, the refrigerant regulating container 30 is disposed closer to the evaporator 18 than the second passage 29 of the liquid-gas heat exchanger 27. It is also possible. Further, it may be either a structure without the throttle 33 or a structure without the liquid-gas heat exchanger 27. This refrigeration cycle can be used in various refrigeration systems such as air conditioners and showcases other than heat pump water heaters. In addition to carbon dioxide, refrigerants include ethylene. It may be a refrigerant used in supercritical conditions such as petane or nitric oxide. In addition, instead of the refrigerant used in supercritical conditions, dichlorodifluoromethane (R- 12) and chloro difluoromethane (R- 22) ).

Claims

The scope of the claims 1. Refrigeration that returns the refrigerant discharged from the compressor (15) to the compressor (15) through the gas cooler (16), the pressure reducing mechanism (17), and the evaporator (18) in order. At Psych Nore,  A refrigerant regulating container (30) connected to a refrigerant passage (22) between the pressure reducing mechanism (17) and the evaporator (18) via a connection passage (31);  The refrigeration cycle is characterized in that the refrigerant adjustment container is arranged in a temperature environment that changes depending on the outside air temperature. 2. The refrigeration cycle according to claim 1, wherein the temperature environment that changes depending on the outside air temperature is formed by a refrigerant ranging from the evaporator outlet to the compressor inlet. 3. Refrigerant adjustment container (30) 1 Attached to the refrigerant pipe (24) from the evaporator outlet to the compressor inlet, the refrigerant in the refrigerant pipe (24) and the refrigerant adjustment container (30) 3. The refrigeration cycle of claim 2, wherein heat is exchanged with a refrigerant in the refrigeration cycle. 4. In the refrigerant passage (22) between the pressure reducing mechanism (17) and the evaporator (18), the refrigerant is narrowed to the evaporator (18) side from the connection (32) of the connection passage (31). (4) The refrigeration plant according to any one of claims 1 to 3, characterized in that the refrigeration plant is interposed.  5. The refrigeration cycle according to claim 1, wherein the refrigerant adjustment container (30) is arranged so as to be exposed to outside air.  6. The refrigeration cycle of claim 1, wherein the refrigerant adjustment container (30) is arranged in an air passage created by a fan (40) attached to the evaporator (18).  7. The refrigeration cycle of claim 6, wherein the refrigerant adjustment container (30) is disposed downstream of the evaporator (18). 8. The refrigeration cycle according to claim 1, wherein the temperature environment that changes depending on the outside air temperature is configured by heating or cooling the refrigerant adjustment container (30) with a Peltier element or the like. 9. The refrigeration cycle of claim 1, wherein the refrigerant adjustment container (30) is arranged to exchange heat with water whose temperature changes depending on the outside air temperature. 10. In the refrigerant passage (22) between the pressure reducing mechanism (17) and the evaporator (18), the throttle is narrowed to the evaporator (18) side from the connection part (32) of the connection passage (31). (33), heat exchange between the refrigerant in the refrigerant adjustment container (30) and the refrigerant near the inlet of the evaporator (18) downstream of the restrictor (33). The refrigeration cycle of claim 1, wherein the adjustment vessel (30) is provided with a heater (H) for adjusting a refrigerant amount.  1 1. The refrigeration cycle according to any one of claims 1 to 10, wherein the high pressure side is operated at a supercritical pressure.