Refrigerating device

Abstract

To solve the problem in a refrigerating device comprising an adsorption type refrigeration cycle, in which it is necessary to recover as much as possible generated adsorption heat or desorption heat.SOLUTION: A refrigerating device 100 comprises a heat source side circuit 101, a utilization side circuit 102, and a control unit 105. The heat source side circuit 101 comprises a compressor 131, a first adsorber 121, a second adsorber 122, a switching mechanism 135, and a refrigerant flow passage 111. The utilization side circuit 102 comprises a first heat medium flow passage 112. The first adsorber 121 and the second adsorber 122 each comprise an adsorbent 181. The heat source side circuit 101 comprises a first bypass flow passage 211 and a first bypass valve 212. The utilization side circuit 102 comprises a utilization part, a second bypass flow passage 213, and a second bypass valve 214. The control unit 105 opens the first bypass valve 212 during a first period. The control unit 105 closes the second bypass valve 214 during a second period. The first period and the second period at least partially overlap.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] Regarding refrigeration equipment. [Background technology]

[0002] Conventionally, refrigeration systems equipped with an adsorption refrigeration cycle have been used. Patent Document 1 (U.S. Patent Application Publication No. 2023 / 0417459) discloses an example of such a refrigeration system, which includes a heat source circuit having a pair of adsorbers that alternately adsorb and desorb a refrigerant, and a user circuit through which a heat medium circulates to recover the heat of adsorption or desorption of the refrigerant. The heat source circuit alternates between a mode in which the refrigerant is adsorbed by one adsorber and desorbed by the other adsorber, and a mode in which the refrigerant is desorbed by the one adsorber and adsorbed by the other adsorber. This allows the user circuit to continuously recover heat from the heat source circuit using the heat medium. Summary of the Invention [Problem to be solved by the invention]

[0003] In a heat source circuit of a refrigeration apparatus equipped with an adsorption refrigeration cycle, heat of adsorption or desorption is generated, and in such a refrigeration apparatus, it is necessary to recover as much of the generated heat of adsorption or desorption as possible. [Means for solving the problem]

[0004] A refrigeration apparatus according to a first aspect includes a heat source-side circuit, a utilization-side circuit, and a control unit. The heat source-side circuit includes a compressor, a first adsorption device, a second adsorption device, a switching mechanism, and a refrigerant flow path through which a refrigerant flows. The utilization-side circuit includes a first heat medium flow path through which a first heat medium flows. The compressor draws in and compresses low-pressure refrigerant, and discharges it as high-pressure refrigerant. The first and second adsorption devices include adsorbents that adsorb and desorb the refrigerant in response to changes in the refrigerant pressure. The first and second adsorption devices recover hot heat generated when the adsorbent adsorbs the refrigerant, and cold heat generated when the adsorbent desorbs the refrigerant. The switching mechanism is capable of switching the refrigerant flow path between a first state and a second state. In the first state, the discharge side of the compressor is connected to the first adsorption device to create a high-pressure state inside the first adsorption device, and the suction side of the compressor is connected to the second adsorption device to create a low-pressure state inside the second adsorption device. In the second state, the suction side of the compressor is connected to the first adsorber to create a low-pressure state inside the first adsorber, and the discharge side of the compressor is connected to the second adsorber to create a high-pressure state inside the second adsorber. The first adsorber recovers hot heat by the first heat medium when the refrigerant flow path is in the first state, and recovers cold heat by the first heat medium when the refrigerant flow path is in the second state. The second adsorber recovers cold heat by the first heat medium when the refrigerant flow path is in the first state, and recovers hot heat by the first heat medium when the refrigerant flow path is in the second state. The heat source side circuit has a first bypass flow path and a first valve. The first bypass flow path connects the first adsorber and the second adsorber without passing through the compressor. The first valve is provided in the first bypass flow path. The utilization side circuit has a utilization unit, a second bypass flow path, and a second valve. The utilization unit utilizes the heat of the first heat medium. The second bypass flow path bypasses the utilization unit. The second valve is provided in the second bypass flow path. The control unit opens the first valve during a first period. The control unit controls the switching mechanism to switch between the first state and the second state at a point in time a predetermined period before the start of the first period, simultaneously with the start of the first period, or at a point in time a predetermined period after the start of the first period. The control unit closes the second valve during the second period. The first period at least partially overlaps with the second period.

[0005] A refrigeration apparatus according to a first aspect switches the refrigerant flow path at a point in time a predetermined period before the start of a first period in which the first valve of the heat source side circuit is opened, simultaneously with the start of the first period, or at a point in time a predetermined period after the start of the first period. The first period overlaps with a second period in which the second valve of the utilization side circuit is closed. By opening the first valve, the difference between the refrigerant pressure in the first adsorption unit and the refrigerant pressure in the second adsorption unit is reduced. Furthermore, by closing the second valve, hot or cold heat can be recovered and stored for later use. Thus, in the refrigeration apparatus according to the first aspect, the first period in which the first valve is open at least partially overlaps with the second period in which the second valve is closed, so that heat of adsorption or desorption heat can be sufficiently recovered even during the first period.

[0006] A refrigeration apparatus according to a second aspect is the refrigeration apparatus according to the first aspect, wherein the control unit starts the second period simultaneously with the start of the first period, or starts the second period during the first period.

[0007] A refrigeration apparatus according to a third aspect is the refrigeration apparatus according to the first or second aspect, wherein the control unit ends the second period after the first period ends and before switching between the first state and the second state.

[0008] A refrigeration device of a fourth aspect is a refrigeration device of any one of the first to third aspects, wherein the control unit delays the start of the second period when the target value of the amount of heat used in the utilization unit is the first amount of heat from the start of the second period when the target value is a second amount of heat that is lower than the first amount of heat.

[0009] A refrigeration device of a fifth aspect is a refrigeration device of any one of the first to fourth aspects, wherein the control unit causes the end of the second period when the target value of the amount of heat used in the utilization unit is a third amount of heat to occur earlier than the end of the second period when the target value is a fourth amount of heat that is lower than the third amount of heat.

[0010] A refrigeration apparatus according to a sixth aspect is the refrigeration apparatus according to any one of the first to fifth aspects, wherein the utilization section includes a heat exchanger provided in the first heat medium flow path.

[0011] A refrigeration device according to a seventh aspect is the refrigeration device according to any one of the first to fifth aspects, wherein the utilization unit includes a second heat medium flow path through which a second heat medium flows, a heat exchanger, and a heat storage unit. The heat exchanger is provided in the second heat medium flow path. The heat storage units are provided in the first heat medium flow path and the second heat medium flow path, and the hot or cold energy recovered by the first heat medium is recovered into the second heat medium.

[0012] A refrigeration device according to an eighth aspect is the refrigeration device according to any one of the first to seventh aspects, wherein the adsorbent includes a metal-organic framework including metal ions and organic ligands.

[0013] A ninth aspect of the present invention is the refrigeration apparatus of any one of the first to eighth aspects, wherein the refrigerant flowing through the refrigerant flow passage is selected from the group consisting of carbon dioxide, hydrocarbon refrigerant, ammonia, and water. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic diagram of a refrigeration device 100 of a first embodiment. [Figure 2] 1 is a block diagram of a refrigeration device 100 of a first embodiment. [Figure 3] 2 is a schematic diagram of a first adsorption device 121 and a second adsorption device 122 of the first embodiment. FIG. [Figure 4] 4 is a time chart of the first bypass valve 212 and the second bypass valve 214 of the first embodiment. [Figure 5] FIG. 1 is a schematic diagram of a refrigeration device 100 according to a second embodiment. [Figure 6] FIG. 10 is a block diagram of a refrigeration device 100 according to a second embodiment. [Figure 7] FIG. 1 is a schematic diagram of a refrigeration device 100 according to a modified example A. [Figure 8] FIG. 10 is a block diagram of a refrigeration device 100 according to a modified example A. DETAILED DESCRIPTION OF THE INVENTION

[0015] -First embodiment- (1) Overall configuration of the refrigeration device 100 As shown in Fig. 1, the refrigeration apparatus 100 of the first embodiment includes a heat source side circuit 101 and a user side circuit 102. The heat source side circuit 101 has a refrigerant flow path 111 through which a refrigerant flows, and a first bypass flow path 211 through which the refrigerant flows. The first bypass flow path 211 is connected to the refrigerant flow path 111. The user side circuit 102 has a first heat medium flow path 112 through which a first heat medium flows, a second bypass flow path 213 through which the first heat medium flows, and a second heat medium flow path 114 through which a second heat medium flows. The second bypass flow path 213 is connected to the first heat medium flow path 112. The second heat medium flow path 114 is not connected to the first heat medium flow path 112 or the second bypass flow path 213. In Fig. 1, the refrigerant flow path 111, the first bypass flow path 211, and the second heat medium flow path 114 are depicted by bold lines. The refrigerant flowing through the refrigerant flow path 111 and the first bypass flow path 211 is selected from the group consisting of, for example, carbon dioxide, hydrocarbon refrigerant, ammonia, and water. The hydrocarbon refrigerant is selected from the group consisting of, for example, propane, butane, and isobutane. The first heat medium flowing through the first heat medium flow path 112 and the second heat medium flowing through the second heat medium flow path 114 are selected from the group consisting of, for example, water, brine, and air. Brine is a liquid with a freezing point of 0°C or lower. The first heat medium may be the same as or different from the second heat medium. The refrigeration device 100 is, for example, an air conditioner.

[0016] The refrigeration apparatus 100 further includes a control unit 105. As shown in FIG. 2, the control unit 105 controls the operation of each element constituting the heat source side circuit 101 and the utilization side circuit 102. Here, a processor is illustrated as an example of the control unit 105. The processor is made up of various computing devices such as a central processing unit (CPU), a digital signal processor (DSP), a field-programmable gate array (FPGA), and a graphics processing unit (GPU). The processor reads various programs of the apparatus into memory and executes them. The processor loads programs stored in memory into a working area of ​​the memory, executes them, and realizes functions that meet a predetermined purpose by controlling each component, etc. through the execution of the programs.

[0017] (1-1) Heat source side circuit 101 The heat source side circuit 101 constitutes a refrigeration cycle that functions as a heat pump that utilizes heat (hot heat or cold heat) generated when the refrigerant is adsorbed to or desorbed from the adsorbent.

[0018] The heat source side circuit 101 has a compressor 131, a first adsorption device 121, a second adsorption device 122, and a switching mechanism 135. The refrigerant flow path 111 connects the compressor 131, the first adsorption device 121, the second adsorption device 122, and the switching mechanism 135.

[0019] The compressor 131 compresses the refrigerant flowing through the refrigerant flow path 111. The compressor 131 is, for example, a rotary compressor. The compressor 131 draws in low-pressure refrigerant from the refrigerant flow path 111, compresses it, and discharges it into the refrigerant flow path 111 as high-pressure refrigerant. The low-pressure refrigerant is the refrigerant in the refrigerant flow path 111 before being compressed by the compressor 131. The high-pressure refrigerant is the refrigerant in the refrigerant flow path 111 after being compressed by the compressor 131. During operation of the compressor 131, lubricating oil sealed in the refrigerant flow path 111 is supplied to the sliding parts of the compressor 131. A portion of the lubricating oil is accumulated at the bottom of the casing of the compressor 131.

[0020] The first adsorbent 121 and the second adsorbent 122 have an adsorbent that adsorbs and desorbs a refrigerant. In the first adsorbent 121 and the second adsorbent 122, the heat of adsorption or desorption heat is recovered by the first heat medium flowing through the first heat medium flow path 112. The heat of adsorption is hot heat generated when the adsorbent adsorbs the refrigerant. The heat of desorption is cold heat generated when the adsorbent desorbs the refrigerant. The generation of hot heat refers to an increase in the temperature of the first heat medium due to the first heat medium absorbing heat. The generation of cold heat refers to a decrease in the temperature of the first heat medium due to the absorption of heat from the first heat medium. The first adsorbent 121 and the second adsorbent 122 are connected to a switching mechanism 135 in the refrigerant flow path 111.

[0021] The switching mechanism 135 switches the flow direction of the refrigerant flowing through the refrigerant flow path 111. The switching mechanism 135 is, for example, a four-way switching valve. The switching mechanism 135 is configured to be able to switch the refrigerant flow path 111 between a first state in which the flow direction is indicated by the solid line in FIG. 1 and a second state in which the flow direction is indicated by the dashed line in FIG. 1. In the first state, the discharge side of the compressor 131 is connected to the first adsorption device 121, and the suction side of the compressor 131 is connected to the second adsorption device 122. In the second state, the discharge side of the compressor 131 is connected to the second adsorption device 122, and the suction side of the compressor 131 is connected to the first adsorption device 121.

[0022] The control unit 105 controls the compressor 131 and the switching mechanism 135. The control unit 105 controls the rotation speed of the compressor 131. The control unit 105 controls the timing to start the compressor 131 and the timing to stop the compressor 131. The control unit 105 controls the switching mechanism 135 to switch the refrigerant flow path 111 between a first state and a second state.

[0023] The control unit 105 controls the switching mechanism 135 so that the period during which the refrigerant flow path 111 is in the first state and the period during which the refrigerant flow path 111 is in the second state are the same length. However, the control unit 105 may also control the switching mechanism 135 so that the period during which the refrigerant flow path 111 is in the first state and the period during which the refrigerant flow path 111 is in the second state are different lengths. The period during which the refrigerant flow path 111 is in the first state is the period from the time when the refrigerant flow path 111 switches to the first state to the time when it switches to the second state. The period during which the refrigerant flow path 111 is in the second state is the period from the time when the refrigerant flow path 111 switches to the second state to the time when it switches to the first state.

[0024] The first bypass flow path 211 connects the first adsorber 121 and the second adsorber 122 without passing through the compressor 131. The first bypass flow path 211 connects, in the refrigerant flow path 111, the flow path between the first adsorber 121 and the switching mechanism 135 and the flow path between the second adsorber 122 and the switching mechanism 135.

[0025] The heat source side circuit 101 further includes a first bypass valve 212 that is an opening / closing mechanism that opens and closes the first bypass flow path 211. The first bypass valve 212 is, for example, a solenoid valve. The first bypass valve 212 is attached to a pipe in the first bypass flow path 211 through which the refrigerant flows.

[0026] The control unit 105 controls the opening and closing of the first bypass valve 212 to allow or block the flow of the refrigerant in the first bypass flow path 211.

[0027] (1-2) User side circuit 102 The utilization side circuit 102 functions as a heat transfer means for utilizing the heat generated in the heat source side circuit 101 via the first heat medium or the second heat medium. In this embodiment, the utilization side circuit 102 uses the second heat medium as a heat source. The first heat medium flowing through the first heat medium flow path 112 causes the second heat medium flowing through the second heat medium flow path 114 to recover the hot heat (adsorption heat) or cold heat (desorption heat) recovered in the first adsorption device 121 and the second adsorption device 122. The second heat medium flowing through the second heat medium flow path 114 transports the hot heat or cold heat recovered from the first heat medium to a predetermined location.

[0028] The utilization side circuit 102 includes a first adsorber 121, a second adsorber 122, a first fluid pump 141, a first heat exchanger 142, a first fan 143, a first on-off valve 144, a third fluid pump 145, a second on-off valve 146, a heat storage unit 149, a second fluid pump 151, a second heat exchanger 152, a second fan 153, and flow path changing units 156-159. The first heat medium flow path 112 connects the first fluid pump 141, the first on-off valve 144, the heat storage unit 149, the first adsorber 121, the second fluid pump 151, the second heat exchanger 152, the second adsorber 122, and the flow path changing units 156-159. The second heat medium flow path 114 connects the third fluid pump 145, the second on-off valve 146, the first heat exchanger 142, and the heat storage section 149.

[0029] The first fluid pump 141 sends the first heat medium to the heat storage unit 149 or the second bypass flow path 213 .

[0030] The second fluid pump 151 sends the first heat medium to the second heat exchanger 152. The second heat exchanger 152 exchanges heat between the first heat medium and air. The second fan 153 generates a flow of air passing through the second heat exchanger 152 so that heat exchange occurs in the second heat exchanger 152.

[0031] The third fluid pump 145 sends the second heat medium to the first heat exchanger 142. The first heat exchanger 142 exchanges heat between the second heat medium and air. The first fan 143 generates a flow of air passing through the first heat exchanger 142 so that heat exchange occurs in the first heat exchanger 142.

[0032] The first on-off valve 144 is, for example, a solenoid valve. The first on-off valve 144 is attached to the first heat medium flow path 112 between the first fluid pump 141 and the heat storage unit 149.

[0033] The second on-off valve 146 is, for example, a solenoid valve. The second on-off valve 146 is attached to the second heat medium flow path 114 between the third fluid pump 145 and the first heat exchanger 142.

[0034] The heat storage unit 149 can store heat and extract the stored heat. The heat storage unit 149 performs heat exchange between the first heat medium flowing through the first heat medium flow path 112 and the second heat medium flowing through the second heat medium flow path 114. The heat storage unit 149 has a heat storage tank 149a and a communicating heat transfer pipe 149b. The heat storage tank 149a is a container in which the first heat medium is stored as a heat storage medium. The communicating heat transfer pipe 149b is provided inside the heat storage tank 149a. The communicating heat transfer pipe 149b is a single-pass or multi-pass heat transfer pipe through which the second heat medium flows.

[0035] The flow path changing units 156-159 change the connection state of the first heat medium flow path 112 to change the flow path through which the first heat medium flows. The flow path changing units 156-159 are, for example, three-way switching valves. The flow path changing units 156-159 are configured to be able to switch the first heat medium flow path 112 between a third connection state indicated by the solid line in FIG. 1 and a fourth connection state indicated by the dashed line in FIG. 1.

[0036] The first heat medium flow path 112 has two independent flow paths, a first circulation flow path and a second circulation flow path, in each of the third and fourth states. The first heat medium circulates through both the first and second circulation flow paths. In Fig. 1, the flow direction of the first heat medium in the third state is indicated by a solid line, and the flow direction of the first heat medium in the fourth state is indicated by a dashed line.

[0037] In the third state, the first circulation flow path connects the first fluid pump 141, the heat storage unit 149, the flow path changing unit 156, the first adsorption device 121, and the flow path changing unit 157. In the third state, the second circulation flow path connects the second fluid pump 151, the second heat exchanger 152, the flow path changing unit 158, the second adsorption device 122, and the flow path changing unit 159.

[0038] In the fourth state, the first circulation flow path connects the first fluid pump 141, the heat storage unit 149, the flow path changing unit 156, the second adsorption device 122, and the flow path changing unit 157. In the fourth state, the second circulation flow path connects the second fluid pump 151, the second heat exchanger 152, the flow path changing unit 158, the first adsorption device 121, and the flow path changing unit 159.

[0039] The second heat medium circulates through the second heat medium flow path 114. In Fig. 1, the flow direction of the second heat medium is indicated by a solid line.

[0040] The control unit 105 controls the first fluid pump 141, the first fan 143, the first on-off valve 144, the third fluid pump 145, the second on-off valve 146, the second fluid pump 151, the second fan 153, and the flow path changing units 156-159. The control unit 105 controls the capacities of the first fluid pump 141, the second fluid pump 151, and the third fluid pump 145. The control unit 105 controls the rotation speeds of the first fan 143 and the second fan 153. The control unit 105 controls the flow path changing units 156-159 to switch the first heat medium flow path 112 between a third state and a fourth state. The control unit 105 controls the opening and closing of the first on-off valve 144 to allow or block the flow of refrigerant in the first heat medium flow path 112. The control unit 105 controls the second on-off valve 146 to open or close, thereby allowing or blocking the flow of refrigerant in the second heat medium flow path 114.

[0041] The second bypass flow path 213 bypasses the heat storage unit 149 in the first heat medium flow path 112. The second bypass flow path 213 connects, in the first heat medium flow path 112, the flow path between the first fluid pump 141 and the first on-off valve 144 and the flow path between the heat storage unit 149 and the flow path changing unit 156.

[0042] The utilization side circuit 102 further includes a second bypass valve 214, which is an opening / closing mechanism that opens and closes the second bypass flow path 213. The second bypass valve 214 is, for example, a solenoid valve. The second bypass valve 214 is attached to the second bypass flow path 213.

[0043] The control unit 105 controls the opening and closing of the second bypass valve 214 to allow or block the flow of the refrigerant in the second bypass flow path 213.

[0044] The control unit 105 controls the second bypass valve 214 and the first on-off valve 144 in conjunction with each other. The control unit 105 controls the second bypass valve 214 and the first on-off valve 144 so that the first on-off valve 144 is opened while the second bypass valve 214 is closed, and the first on-off valve 144 is closed while the second bypass valve 214 is open.

[0045] (1-3) First adsorption device 121 and second adsorption device 122 The first adsorption device 121 and the second adsorption device 122 each include a heat recovery member, an adsorption material, and a casing. The first adsorption device 121 and the second adsorption device 122 each have a first space through which a refrigerant flows and a second space through which a first heat medium flows. The first space is part of the refrigerant flow path 111. The second space is part of the first heat medium flow path 112. The first space and the second space do not communicate with each other.

[0046] The heat recovery member separates the first space from the second space. The adsorbent is provided in the first space. The adsorbent adsorbs and desorbs the refrigerant in the first space in response to changes in the pressure of the refrigerant in the first space. The adsorbent is supported on a first surface, which is a surface of the heat recovery member.

[0047] The adsorbent supported on the first surface includes a metal-organic framework (MOF) containing metal ions and organic ligands. A metal-organic framework is a porous material with a very large specific surface area obtained by the reaction of metal ions with organic ligands. In a metal-organic framework, organic ligands are linked to metal ions to obtain a polymer structure with numerous openings inside. The opening size and topology of a metal-organic framework can be adjusted by selecting and combining metal ions and organic ligands. Therefore, the opening size of a metal-organic framework can be adjusted by selecting and combining metal ions and organic ligands, and it can selectively adsorb target substances. A metal-organic framework can be used, for example, as a porous material capable of selectively storing and separating molecules and ions.

[0048] In the refrigeration device 100, the metal-organic framework is used as an adsorbent for adsorbing and desorbing the refrigerant flowing through the refrigerant flow path 111. Examples of the metal-organic framework include MOF-5, MOF-200, UiO-66, and MIL-101. The adsorbent used in the refrigeration device 100 is, for example, a powder of the metal-organic framework or a molded product of the metal-organic framework. In this case, the adsorbent is supported on the first surface by adhering a mixture of the adsorbent and a binder to the first surface. Examples of the binder include an acrylic resin, a polyester resin, a polyolefin resin, and a polyurethane resin.

[0049] The heat recovery member is a cross-fin type. As shown in FIG. 3, the heat recovery member includes a plurality of fins 161 and heat transfer tubes 162. Each heat transfer tube 162 has a plurality of straight tube portions 162a extending linearly and a folded portion 162b connecting two straight tube portions 162a. In FIG. 3, the thickness of the heat transfer tube 162 is omitted. Each of the fins 161 has through holes in its thickness direction through which the straight tube portions 162a of the heat transfer tube 162 penetrate. The fins 161 are stacked around the straight tube portions 162a of the heat transfer tube 162 at predetermined intervals along the direction in which the straight tube portions 162a extend. A first end 162c and a second end 162d of the heat transfer tube 162 are connected to the first heat medium flow path 112. The fins 161 and the heat transfer tubes 162 are housed in a casing 163. The casing 163 has an inlet 163 a connected to the refrigerant flow path 111 .

[0050] The refrigerant flowing through the refrigerant flow path 111 flows into the casing 163 through the inlet 163a, and flows out of the casing 163 through the inlet 163a. ​​The first heat medium flowing through the first heat medium flow path 112 flows into the heat transfer tube 162 through the first end 162c, and flows out of the heat transfer tube 162 through the second end 162d.

[0051] As shown in FIG. 3 , the first space 164a through which the refrigerant flows is a space inside the casing 163 and outside the heat transfer tube 162. The second space 164b through which the first heat medium flows is a space inside the casing 163 and inside the heat transfer tube 162. The first surface 182, on which the adsorbent 181 that adsorbs and desorbs the adsorbent is supported, includes at least a portion of the outer surfaces of the multiple fins 161 and the heat transfer tube 162. The first surface 182 is, for example, the surfaces of the multiple fins 161 and the outer surface of the heat transfer tube 162. The first surface 182 is in contact with the first space 164a. Therefore, the refrigerant in the first space 164a comes into contact with the adsorbent 181 supported on the first surface 182.

[0052] The adsorbent 181 adsorbs the refrigerant in the first space 164a when the pressure of the refrigerant in the first space 164a is equal to or higher than the adsorption pressure. The adsorbent 181 desorbs the refrigerant in the first space 164a when the pressure of the refrigerant in the first space 164a is equal to or lower than the desorption pressure. The adsorption pressure is the minimum value of the range of pressures at which the adsorbent 181 can adsorb the refrigerant at the temperature of the first space 164a. The desorption pressure is the maximum value of the range of pressures at which the adsorbent 181 can desorb the refrigerant at the temperature of the first space 164a. The adsorption pressure and desorption pressure vary depending on the type of adsorbent 181 and the refrigerant.

[0053] (2) Operation of the Refrigeration Device 100 The operation of the refrigeration apparatus 100 will be described assuming that the refrigeration apparatus 100 is an air conditioner. In this case, the first heat exchanger 142 is an indoor heat exchanger, and the second heat exchanger 152 is an outdoor heat exchanger.

[0054] The adsorbent 181 of the first adsorption device 121 and the second adsorption device 122 adsorbs and desorbs the refrigerant in the refrigerant flow path 111. The adsorbent 181 adsorbs the refrigerant when it is in contact with a refrigerant whose pressure is equal to or higher than the adsorption pressure in the first space 164a. The adsorbent 181 desorbs the refrigerant when it is in contact with a refrigerant whose pressure is equal to or lower than the desorption pressure in the first space 164a.

[0055] When the refrigerant flow path 111 is in the first state, the discharge side of the compressor 131 is connected to the first adsorber 121 to create a high-pressure state inside the first adsorber 121, and the suction side of the compressor 131 is connected to the second adsorber 122 to create a low-pressure state inside the second adsorber 122. When the inside of the first adsorber 121 is in a high-pressure state, the adsorbent 181 of the first adsorber 121 is in contact with the high-pressure refrigerant in the first space 164a. When the inside of the second adsorber 122 is in a low-pressure state, the adsorbent 181 of the second adsorber 122 is in contact with the low-pressure refrigerant in the first space 164a.

[0056] When the refrigerant flow path 111 is in the second state, the suction side of the compressor 131 is connected to the first adsorber 121 to create a low-pressure state inside the first adsorber 121, and the discharge side of the compressor 131 is connected to the second adsorber 122 to create a high-pressure state inside the second adsorber 122. When the inside of the first adsorber 121 is in a low-pressure state, the adsorbent 181 of the first adsorber 121 is in contact with the low-pressure refrigerant in the first space 164a. When the inside of the second adsorber 122 is in a high-pressure state, the adsorbent 181 of the second adsorber 122 is in contact with the high-pressure refrigerant in the first space 164a.

[0057] The following describes changes in the adsorption amount, which is the amount of refrigerant adsorbed by the adsorbent 181, when the refrigerant flow path 111 is in the first state. When the switching mechanism 135 switches from the second state to the first state, the adsorption amount of the adsorbent 181 in the first adsorption device 121 is the first adsorption amount, and the adsorption amount of the adsorbent 181 in the second adsorption device 122 is the second adsorption amount. The second adsorption amount is larger than the first adsorption amount. The second adsorption amount is the maximum amount of refrigerant that can be adsorbed by the adsorbent 181. The second adsorption amount includes not only the theoretical maximum amount but also an amount that can change depending on the time the high-pressure pressure or high-pressure state is maintained. The pressure of the high-pressure refrigerant is equal to or higher than the adsorption pressure, and the pressure of the low-pressure refrigerant is equal to or lower than the desorption pressure.

[0058] When the refrigerant flow path 111 is in the first state, the adsorbent 181 in the first adsorber 121 contacts a high-pressure refrigerant, and the adsorbent 181 in the second adsorber 122 contacts a low-pressure refrigerant. In the first adsorber 121, the adsorbent 181 gradually adsorbs the refrigerant, releasing heat in the process. In the second adsorber 122, the adsorbent 181 gradually desorbs the refrigerant, absorbing heat in the process. Therefore, the adsorption amount of the adsorbent 181 in the first adsorber 121 increases from the first adsorption amount to the second adsorption amount, and the adsorption amount of the adsorbent 181 in the second adsorber 122 decreases from the second adsorption amount to the first adsorption amount.

[0059] The following describes a change in the adsorption amount, which is the amount of refrigerant adsorbed by the adsorbent 181, when the refrigerant flow path 111 is in the second state. When the switching mechanism 135 switches from the first state to the second state, the adsorption amount of the adsorbent 181 in the first adsorption device 121 is the second adsorption amount, and the adsorption amount of the adsorbent 181 in the second adsorption device 122 is the first adsorption amount.

[0060] When the refrigerant flow path 111 is in the second state, the adsorbent 181 in the first adsorbent 121 contacts the low-pressure refrigerant, and the adsorbent 181 in the second adsorbent 122 contacts the high-pressure refrigerant. In the first adsorbent 121, the adsorbent 181 gradually desorbs the refrigerant, absorbing heat in the process. In the second adsorbent 122, the adsorbent 181 gradually adsorbs the refrigerant, releasing heat in the process. Therefore, the adsorption amount of the adsorbent 181 in the first adsorbent 121 decreases from the second adsorption amount to the first adsorption amount, and the adsorption amount of the adsorbent 181 in the second adsorbent 122 increases from the first adsorption amount to the second adsorption amount.

[0061] When the refrigerant flow path 111 is in the first state and the first heat medium flow path 112 is in the third state, in the first adsorber 121, hot heat generated in the process of the adsorbent 181 adsorbing the refrigerant in the first space 164a is recovered by the first heat medium in the second space 164b. On the other hand, in the second adsorber 122, cold heat generated in the process of the adsorbent 181 desorbing the refrigerant adsorbed by the adsorbent 181 is recovered by the first heat medium in the second space 164b. Therefore, in the first adsorber 121, hot heat is recovered by the first heat medium flowing through the first circulation flow path, and in the second adsorber 122, cold heat is recovered by the first heat medium flowing through the second circulation flow path.

[0062] Thereafter, when the adsorption amount of the adsorbent 181 in the first adsorption device 121 reaches the second adsorption amount, it becomes difficult for the adsorbent 181 in the first adsorption device 121 to adsorb the refrigerant. When this state is reached, the refrigerant flow path 111 is switched from the first state to the second state, and the first heat medium flow path 112 is switched from the third state to the fourth state.

[0063] When the refrigerant flow path 111 is in the second state and the first heat medium flow path 112 is in the fourth state, in the second adsorption device 122, hot heat generated in the process of the adsorbent 181 adsorbing the refrigerant in the first space 164a is recovered by the first heat medium in the second space 164b. On the other hand, in the first adsorption device 121, cold heat generated in the process of the adsorbent 181 desorbing the refrigerant adsorbed by the adsorbent 181 is recovered by the first heat medium in the second space 164b. Therefore, in the first adsorption device 121, cold heat is recovered by the first heat medium flowing through the second circulation flow path, and in the second adsorption device 122, hot heat is recovered by the first heat medium flowing through the first circulation flow path.

[0064] Thereafter, when the adsorption amount of the adsorbent 181 in the second adsorption device 122 reaches the second adsorption amount, it becomes difficult for the adsorbent 181 in the second adsorption device 122 to adsorb the refrigerant. When this state is reached, the refrigerant flow path 111 is switched from the second state to the first state, and the first heat medium flow path 112 is switched from the fourth state to the third state.

[0065] As described above, by alternately switching the refrigerant flow path 111 between the first state and the second state, it is possible to continuously adsorb or desorb the refrigerant to the adsorbent 181 in either the first adsorber 121 or the second adsorber 122. By alternately switching the first heat medium flow path 112 between the third state and the fourth state in accordance with the switching between the first state and the second state, it is possible to continuously recover, by the first heat medium flowing through the first circulation flow path, the heat generated when the adsorbent 181 adsorbs the refrigerant.

[0066] Furthermore, when the refrigerant flow path 111 is in the first state and the first heat medium flow path 112 is in the fourth state, the first adsorber 121 recovers hot heat to the first heat medium flowing through the second circulation flow path, and the second adsorber 122 recovers cold heat to the first heat medium flowing through the first circulation flow path. When the refrigerant flow path 111 is in the second state and the first heat medium flow path 112 is in the third state, the first adsorber 121 recovers cold heat to the first heat medium flowing through the first circulation flow path, and the second adsorber 122 recovers hot heat to the first heat medium flowing through the second circulation flow path. Therefore, by alternately switching the first heat medium flow path 112 between the fourth state and the third state in accordance with the switching between the first state and the second state, it is possible to continuously recover cold heat generated when the adsorbent 181 desorbs the refrigerant by the first heat medium flowing through the first circulation flow path.

[0067] Therefore, the refrigeration device 100 can continue to supply the first heat medium heated by the recovered hot heat or the first heat medium cooled by the recovered cold heat to the heat storage section 149 connected to the first circulation flow path.

[0068] Furthermore, the first heat medium that has recovered hot heat or cold heat while flowing through the first circulation flow path of the first heat medium flow path 112 is stored in the heat storage tank 149a of the heat storage unit 149, so that the heat storage unit 149 can store the hot heat or cold heat. The second heat medium circulating through the second heat medium flow path 114 exchanges heat with the first heat medium in the heat storage tank 149a while flowing through the communicating heat transfer pipe 149b of the heat storage unit 149, and can recover the hot heat or cold heat stored in the heat storage unit 149. When the first heat medium recovers hot heat, the second heat medium recovers the hot heat in the heat storage unit 149. When the first heat medium recovers cold heat, the second heat medium recovers cold heat.

[0069] Therefore, the refrigeration device 100 can supply the second heat medium heated by the recovered hot heat or the second heat medium cooled by the recovered cold heat to the first heat exchanger 142 connected to the second heat medium flow path 114.

[0070] (3) Control of the first bypass valve 212 and the second bypass valve 214 The first bypass valve 212 is temporarily opened when the refrigerant flow path 111 is switched between the first state and the second state, and is closed during other periods.

[0071] When the first bypass valve 212 is closed and the refrigerant flow path 111 is in a first state, the inside of the first adsorption device 121 is in a high-pressure state and the inside of the second adsorption device 122 is in a low-pressure state. When the first bypass valve 212 is closed and the refrigerant flow path 111 is in a second state, the inside of the first adsorption device 121 is in a low-pressure state and the inside of the second adsorption device 122 is in a high-pressure state. Therefore, when the first bypass valve 212 is closed, the pressure in the first space 164a of the first adsorption device 121 and the pressure in the first space 164a of the second adsorption device 122 are different from each other.

[0072] When the first bypass valve 212 is opened to switch the refrigerant flow path 111 between the first state and the second state, the first space 164a of the first adsorber 121 and the first space 164a of the second adsorber 122 are connected to each other. This reduces the pressure difference between the first space 164a of the first adsorber 121 and the first space 164a of the second adsorber 122, thereby achieving pressure equalization. In other words, the difference between the pressure in the first adsorber 121 and the pressure in the second adsorber 122 after a predetermined time has elapsed since the first bypass valve 212 was opened is smaller than the difference between the pressure in the first adsorber 121 and the pressure in the second adsorber 122 before the first bypass valve 212 was opened.

[0073] The second bypass valve 214 is temporarily closed during the period when hot or cold heat is stored in the heat storage section 149. During other periods, the second bypass valve 214 is open.

[0074] While the second bypass valve 214 is closed, the first on-off valve 144 is open. In this case, the first heat medium delivered from the first fluid pump 141 is sent to the heat storage unit 149 without passing through the second bypass flow path 213. While the second bypass valve 214 is open, the first on-off valve 144 is closed. In this case, the first heat medium delivered from the first fluid pump 141 is sent to the flow path changing unit 156 through the second bypass flow path 213 without being sent to the heat storage unit 149.

[0075] When the refrigeration device 100 stores hot heat in the heat storage unit 149, the second bypass valve 214 is closed when the temperature of the first heat medium from which the hot heat has been recovered is equal to or higher than a predetermined value. In this case, the first heat medium from which the hot heat has been recovered is stored in the heat storage tank 149a of the heat storage unit 149. When the refrigeration device 100 stores hot heat in the heat storage unit 149, the second bypass valve 214 is opened when the temperature of the first heat medium from which the hot heat has been recovered is lower than a predetermined value. In this case, the first heat medium flows through the second bypass flow path 213 and is not stored in the heat storage tank 149a.

[0076] When the refrigeration device 100 stores cold energy in the heat storage unit 149, the second bypass valve 214 is closed when the temperature of the first heat medium from which the cold energy has been recovered is equal to or lower than a predetermined value. In this case, the first heat medium from which the cold energy has been recovered is stored in the heat storage tank 149a of the heat storage unit 149. When the refrigeration device 100 stores cold energy in the heat storage unit 149, the second bypass valve 214 is opened when the temperature of the first heat medium from which the cold energy has been recovered is higher than a predetermined value. In this case, the first heat medium flows through the second bypass flow path 213 and is not stored in the heat storage tank 149a.

[0077] During operation of the refrigeration apparatus 100, the control unit 105 controls the first bypass valve 212 and the second bypass valve 214 at the timing shown in FIG.

[0078] The "First Bypass Valve" time chart in Figure 4 shows the state of the first bypass valve 212. During the "Open" period, the first bypass valve 212 is open. During the "Closed" period, the first bypass valve 212 is closed.

[0079] 4 represents the pressure in the first space 164a of the first adsorption device 121 and the second adsorption device 122. The solid line represents the pressure in the first space 164a of the first adsorption device 121, in other words, the pressure of the refrigerant in the first adsorption device 121. The dotted line represents the pressure in the first space 164a of the second adsorption device 122, in other words, the pressure of the refrigerant in the second adsorption device 122.

[0080] The "Second Bypass Valve" time chart in Figure 4 shows the state of the second bypass valve 214. During the "open" period, the second bypass valve 214 is open. During the "closed" period, the second bypass valve 214 is closed.

[0081] The time chart of "Temperature of first heat medium" in FIG. 4 represents the temperature of the first heat medium immediately after the hot heat is collected when the heat storage unit 149 stores the hot heat. Specifically, this temperature represents the temperature of the first heat medium immediately after it flows out of the first adsorption device 121 and the second adsorption device 122. This temperature is measured, for example, by a temperature sensor installed near the second end 162d of the heat transfer tube 162 of the first adsorption device 121 and the second adsorption device 122. The solid line represents the temperature of the first heat medium immediately after the hot heat is collected in the first adsorption device 121. The dotted line represents the temperature of the first heat medium immediately after the hot heat is collected in the second adsorption device 122.

[0082] 4 shows one operation cycle of the refrigeration apparatus 100 and periods P1-P4. One cycle is made up of periods P1-P4. Period P1 is a period during which the first bypass valve 212 is opened and pressure equalization is performed. During period P1, the refrigerant flow path 111 is switched from the second state to the first state. During period P2, the first bypass valve 212 is closed and the refrigerant flow path 111 is in the first state. During period P3, the first bypass valve 212 is opened and pressure equalization is performed. During period P3, the refrigerant flow path 111 is switched from the first state to the second state. During period P4, the first bypass valve 212 is closed and the refrigerant flow path 111 is in the second state.

[0083] In FIG. 4, initially, the refrigerant flow path 111 is in the second state, the first space 164a of the first adsorption device 121 is in a low-pressure state, and the first space 164a of the second adsorption device 122 is in a high-pressure state (period P4).

[0084] Next, when the first bypass valve 212 is opened, the pressure of the refrigerant in the first adsorption device 121 increases and the pressure of the refrigerant in the second adsorption device 122 decreases due to pressure equalization (period P1). As a result, the pressures in the first spaces 164a in the first adsorption device 121 and the second adsorption device 122 become approximately the same. During pressure equalization, the refrigerant flow path 111 is switched from the second state to the first state.

[0085] Next, when the first bypass valve 212 is closed, the pressure of the refrigerant in the first adsorption device 121 increases, and the pressure of the refrigerant in the second adsorption device 122 decreases (period P2). The pressure of the refrigerant in the first adsorption device 121 increases to a predetermined value and then becomes approximately constant. The pressure of the refrigerant in the second adsorption device 122 decreases to a predetermined value and then becomes approximately constant. The refrigerant flow path 111 is in a first state, the first space 164a of the first adsorption device 121 is in a high-pressure state, and the first space 164a of the second adsorption device 122 is in a low-pressure state.

[0086] Next, when the first bypass valve 212 is opened, the pressure of the refrigerant in the first adsorption device 121 decreases and the pressure of the refrigerant in the second adsorption device 122 increases due to pressure equalization (period P3). As a result, the pressures in the first spaces 164a in the first adsorption device 121 and the second adsorption device 122 become approximately the same. During pressure equalization, the refrigerant flow path 111 is switched from the first state to the second state.

[0087] Next, when the first bypass valve 212 is closed, the pressure of the refrigerant in the first adsorption device 121 decreases, and the pressure of the refrigerant in the second adsorption device 122 increases (period P4). The pressure of the refrigerant in the first adsorption device 121 decreases to a predetermined value and then becomes approximately constant. The pressure of the refrigerant in the second adsorption device 122 increases to a predetermined value and then becomes approximately constant. The refrigerant flow path 111 is in the second state, the first space 164a of the first adsorption device 121 is in a low-pressure state, and the first space 164a of the second adsorption device 122 is in a high-pressure state.

[0088] Next, a description will be given of the change in temperature of the first heat medium immediately after it flows out of the first adsorption device 121 and the second adsorption device 122, as shown in FIG.

[0089] During period P1, the pressure of the refrigerant in the first adsorption device 121 increases, and the refrigerant flow path 111 is switched from the second state to the first state. As a result, the adsorbent 181 of the first adsorption device 121 begins to adsorb the refrigerant, and the first heat medium flowing through the first adsorption device 121 begins to recover the heat of adsorption. Therefore, during period P1, the temperature of the first heat medium immediately after flowing out of the first adsorption device 121 increases.

[0090] Immediately after the refrigerant flow path 111 is switched from the second state to the first state during period P1, the amount of refrigerant adsorbed by the adsorbent 181 of the first adsorber 121 per unit time is maximized, and therefore the heat of adsorption recovered by the first heat medium flowing through the first adsorber 121 is maximized. Subsequently, during period P2, as the adsorbent 181 of the first adsorber 121 adsorbs the refrigerant, the adsorbent 181 of the first adsorber 121 becomes less able to adsorb the refrigerant, and therefore the heat of adsorption recovered by the first heat medium flowing through the first adsorber 121 gradually decreases. Therefore, as shown in FIG. 4 , during periods P1 and P2, the temperature of the first heat medium immediately after flowing out of the first adsorber 121 increases and peaks, and then gradually decreases. Near the end of period P2, the adsorbent 181 of the first adsorber 121 hardly adsorbs the refrigerant, and therefore the temperature of the first heat medium immediately after flowing out of the first adsorber 121 remains substantially constant.

[0091] During period P3, the pressure of the refrigerant in the second adsorption device 122 increases, and the refrigerant flow path 111 is switched from the first state to the second state. As a result, the adsorbent 181 of the second adsorption device 122 begins to adsorb the refrigerant, and the first heat medium flowing through the second adsorption device 122 begins to recover the heat of adsorption. Therefore, during period P3, the temperature of the first heat medium immediately after flowing out of the second adsorption device 122 increases.

[0092] Immediately after the refrigerant flow path 111 is switched from the first state to the second state during period P3, the amount of refrigerant adsorbed by the adsorbent 181 of the second adsorber 122 per unit time is maximized, and therefore the heat of adsorption recovered by the first heat medium flowing through the second adsorber 122 is maximized. Subsequently, during period P4, as the adsorbent 181 of the second adsorber 122 adsorbs the refrigerant, the adsorbent 181 of the second adsorber 122 becomes less able to adsorb the refrigerant, and therefore the heat of adsorption recovered by the first heat medium flowing through the second adsorber 122 gradually decreases. Therefore, as shown in FIG. 4 , during periods P3 and P4, the temperature of the first heat medium immediately after flowing out of the second adsorber 122 increases and peaks, and then gradually decreases. Near the end of period P4, the adsorbent 181 of the second adsorber 122 hardly adsorbs the refrigerant, and therefore the temperature of the first heat medium immediately after flowing out of the second adsorber 122 remains substantially constant.

[0093] As shown in Figure 4, the temperature of the first heat medium immediately after it flows out of the first adsorption device 121 in periods P1 and P2 shows the same change trend as the temperature of the first heat medium immediately after it flows out of the second adsorption device 122 in periods P3 and P4.

[0094] In one operation cycle of the refrigeration apparatus 100, a first period during which the first bypass valve 212 is open at least partially overlaps with a second period during which the second bypass valve 214 is closed. In other words, the control unit 105 starts the second period simultaneously with the start of the first period, or starts the second period during the first period. When starting the second period simultaneously with the start of the first period, the control unit 105 opens the first bypass valve 212 and closes the second bypass valve 214 simultaneously. When starting the second period during the first period, the control unit 105 closes the second bypass valve 214 after opening the first bypass valve 212 and before subsequently closing the first bypass valve 212, as shown in FIG. 4 . During the first period, the control unit 105 switches the refrigerant flow path 111 between the first state and the second state.

[0095] In one operation cycle of the refrigeration apparatus 100, the second period ends after the first period ends and before the refrigerant flow path 111 switches between the first state and the second state. In other words, after closing the first bypass valve 212, the control unit 105 opens the second bypass valve 214 before the refrigerant flow path 111 next switches between the first state and the second state. In FIG. 4, the refrigerant flow path 111 switches between the first state and the second state during the first period in which the first bypass valve 212 is open. Therefore, as shown in FIG. 4, the control unit 105 may open the second bypass valve 214 after closing the first bypass valve 212 and before the first bypass valve 212 next opens.

[0096] When the heat storage unit 149 stores hot heat, the second bypass valve 214 is opened during a period in which the temperature of the first heat medium immediately after flowing out from the first adsorption device 121 and the second adsorption device 122 is equal to or higher than a predetermined target temperature. The target temperature is set, for example, based on a target value of the amount of hot heat stored in the heat storage unit 149. In FIG. 4 , the target temperature is 25°C. The control unit 105 closes the second bypass valve 214 during a period P1 when the temperature of the first heat medium immediately after flowing out from the first adsorption device 121 has risen to the target temperature. Thereafter, the control unit 105 opens the second bypass valve 214 during a period P2 when the temperature of the first heat medium immediately after flowing out from the first adsorption device 121 has fallen to the target temperature. The control unit 105 closes the second bypass valve 214 during a period P3 when the temperature of the first heat medium immediately after flowing out from the second adsorption device 122 has risen to the target temperature. Thereafter, in a period P4, the control unit 105 opens the second bypass valve 214 at the time point when the temperature of the first heat medium immediately after it flows out of the second adsorption device 122 drops to the target temperature.

[0097] When the heat storage unit 149 stores cold energy, the time chart of the temperature of the first heat medium immediately after it flows out of the first adsorption device 121 and the second adsorption device 122 has a shape similar to that of the time chart of "Temperature of the First Heat Medium" in FIG. 4, turned upside down. When the heat storage unit 149 stores cold energy, the second bypass valve 214 is opened during a period in which the temperature of the first heat medium immediately after it flows out of the first adsorption device 121 and the second adsorption device 122 is equal to or lower than a predetermined target temperature. The control unit 105 closes the second bypass valve 214 during a period P1 when the temperature of the first heat medium immediately after it flows out of the first adsorption device 121 drops to the target temperature. Thereafter, the control unit 105 opens the second bypass valve 214 during a period P2 when the temperature of the first heat medium immediately after it flows out of the first adsorption device 121 rises to the target temperature. The control unit 105 closes the second bypass valve 214 during period P3 when the temperature of the first heat medium immediately after flowing out of the second adsorption device 122 drops to the target temperature. Thereafter, the control unit 105 opens the second bypass valve 214 during period P4 when the temperature of the first heat medium immediately after flowing out of the second adsorption device 122 rises to the target temperature.

[0098] In this way, the control unit 105 changes the timing for opening the second bypass valve 214 and the timing for closing the second bypass valve 214 in accordance with the target temperature of the first heat medium.

[0099] (4) Features (4-1) The refrigeration device 100 includes a heat source side circuit 101 having a first bypass flow path 211 and a first bypass valve 212, a utilization side circuit 102 having a second bypass flow path 213 and a second bypass valve 214, and a control unit 105.

[0100] When switching the refrigerant flow path 111 between the first state and the second state, the control unit 105 temporarily opens the first bypass valve 212 to equalize the pressure.

[0101] If the first bypass valve 212 is opened and pressure equalization is performed when the refrigerant flow path 111 switches from the first state to the second state, the pressure in the first space 164a of the first adsorption device 121 decreases and the pressure in the first space 164a of the second adsorption device 122 increases. Therefore, after the refrigerant flow path 111 switches to the second state, the time required for the pressure in the first space 164a of the first adsorption device 121 to decrease and reach the desorption pressure, and the time required for the pressure in the first space 164a of the second adsorption device 122 to increase and reach the adsorption pressure are shortened.

[0102] If the first bypass valve 212 is opened and pressure equalization is performed when the refrigerant flow path 111 switches from the second state to the first state, the pressure in the first space 164a of the first adsorption device 121 increases and the pressure in the first space 164a of the second adsorption device 122 decreases. Therefore, after the refrigerant flow path 111 switches to the first state, the time required for the pressure in the first space 164a of the first adsorption device 121 to increase and reach the adsorption pressure, and the time required for the pressure in the first space 164a of the second adsorption device 122 to decrease and reach the desorption pressure are shortened.

[0103] By repeatedly switching the refrigerant flow path 111 between the first state and the second state, the refrigeration device 100 can continue to recover the hot and cold heat generated when the refrigerant is adsorbed and desorbed by the adsorbent 181 in the first adsorption device 121 and the second adsorption device 122 by the first heat medium flowing through the first heat medium flow path 112 of the utilization side circuit 102.

[0104] After the refrigerant flow path 111 is switched, hot heat is not generated in the first adsorption device 121 or the second adsorption device 122 until the pressure in the first adsorption device 121 or the second adsorption device 122 increases and reaches the adsorption pressure. After the refrigerant flow path 111 is switched, cold heat is not generated in the first adsorption device 121 or the second adsorption device 122 until the pressure in the first adsorption device 121 or the second adsorption device 122 decreases and reaches the desorption pressure.

[0105] Therefore, when the refrigerant flow path 111 switches between the first state and the second state, the longer it takes for the pressure in the first adsorption device 121 and the second adsorption device 122 to reach the adsorption pressure or desorption pressure, the lower the capacity per unit time of the refrigeration device 100.

[0106] The refrigeration apparatus 100 of this embodiment can shorten the time it takes for the pressure in the first adsorption device 121 and the second adsorption device 122 to reach the adsorption pressure or the desorption pressure. Therefore, the refrigeration apparatus 100 can increase the capacity per unit time compared to a case in which the heat source side circuit 101 does not have the first bypass flow path 211 and the first bypass valve 212.

[0107] (4-2) The control unit 105 of the refrigeration apparatus 100 temporarily closes the second bypass valve 214 when switching the refrigerant flow path 111 between the first state and the second state. While the second bypass valve 214 is closed, the first heat medium that has recovered hot heat or cold heat in the first heat medium flow path 112 is stored in the heat storage tank 149a of the heat storage unit 149. This allows the heat storage unit 149 to store hot heat or cold heat.

[0108] The control unit 105 can circulate the second heat medium in the second heat medium flow path 114 by driving the third fluid pump 145 and opening the second on-off valve 146. In this case, the second heat medium exchanges heat with the first heat medium in the heat storage tank 149a while flowing through the heat transfer pipe 149b of the heat storage unit 149, and can recover the hot or cold energy stored in the heat storage unit 149. The hot or cold energy recovered by the second heat medium is utilized by being heat exchanged with air in the first heat exchanger 142.

[0109] The refrigeration apparatus 100 of this embodiment can store the hot heat or cold heat recovered by the first heat medium in the first adsorption device 121 and the second adsorption device 122 in the heat storage unit 149. After storing a predetermined amount of hot heat or cold heat in the heat storage unit 149, the refrigeration apparatus 100 can recover and utilize some or all of the hot heat or cold heat stored in the heat storage unit 149 by the second heat medium. Once the adsorption and desorption of the refrigerant in the first adsorption device 121 and the second adsorption device 122 progresses to a certain extent, the amount of hot heat or cold heat recovered by the first heat medium gradually decreases. Therefore, if the hot heat or cold heat recovered by the first heat medium is directly utilized, the capacity of the refrigeration apparatus 100 may become unstable.

[0110] Therefore, by recovering and utilizing the hot or cold heat stored in the heat storage section 149 using the second heat medium, the refrigeration device 100 can prevent the capacity of the refrigeration device 100 from becoming unstable compared to when the hot or cold heat recovered by the first heat medium is directly utilized.

[0111] (4-3) When the heat storage unit 149 stores hot heat, the control unit 105 of the refrigeration apparatus 100 opens the second bypass valve 214 during a period in which the temperature of the first heat medium immediately after flowing out from the first adsorption device 121 and the second adsorption device 122 is equal to or higher than a predetermined target temperature. When the heat storage unit 149 stores cold heat, the control unit 105 opens the second bypass valve 214 during a period in which the temperature of the first heat medium immediately after flowing out from the first adsorption device 121 and the second adsorption device 122 is equal to or lower than a predetermined target temperature.

[0112] As a result, the control unit 105 can control the temperature of the first heat medium stored in the heat storage tank 149a of the heat storage unit 149 by controlling the second bypass valve 214 based on the target temperature of the first heat medium. Therefore, the refrigeration device 100 can adjust the temperature of the air that has exchanged heat with the second heat medium in the first heat exchanger 142 by setting the target temperature of the first heat medium.

[0113] (4-4) In the refrigeration apparatus 100, a first period during which the first bypass valve 212 is open at least partially overlaps with a second period during which the second bypass valve 214 is closed. When the first bypass valve 212 is opened, the refrigerant flow path 111 is switched between a first state and a second state, and the first heat medium recovers hot heat or cold heat in the first adsorption device 121 and the second adsorption device 122. Therefore, by closing the second bypass valve 214 while the first heat medium is recovering hot heat or cold heat, the heat storage unit 149 can store the hot heat or cold heat recovered by the first heat medium. Thereafter, by opening the second bypass valve 214, the heat storage unit 149 can stop storing the hot heat or cold heat recovered by the first heat medium.

[0114] Therefore, the refrigeration device 100 can adjust the amount of hot or cold heat stored in the heat storage section 149 by opening and closing the first bypass valve 212 and the second bypass valve 214 at appropriate timing.

[0115] Furthermore, in the refrigeration apparatus 100, since the first period at least partially overlaps with the second period, the first heat medium can recover hot heat or cold even during the first period in which pressure equalization is performed. Therefore, the refrigeration apparatus 100 can sufficiently recover hot heat or cold in the first adsorption device 121 and the second adsorption device 122.

[0116] (4-5) The control unit 105 of the refrigeration device 100 can set the start and end points of the second period during which the second bypass valve 214 is closed, depending on the target value of the amount of hot or cold heat stored in the heat storage unit 149.

[0117] For example, the lower the target value of the amount of hot or cold heat stored in the heat storage unit 149, the earlier the timing at which the control unit 105 closes the second bypass valve 214 to bring the start of the second period forward, and / or the later the timing at which the control unit 105 opens the second bypass valve 214 to bring the end of the second period forward.

[0118] The earlier the start point of the second period, the earlier the first heat medium that has recovered hot heat or cold heat in the first adsorption device 121 and the second adsorption device 122 starts to flow into the heat storage unit 149. As shown in Fig. 4, the earlier the first heat medium that has recovered hot heat starts to flow into the heat storage unit 149, the lower the temperature of the first heat medium at which the heat storage unit 149 starts to store hot heat. Similarly, the earlier the first heat medium that has recovered cold heat starts to flow into the heat storage unit 149, the higher the temperature of the first heat medium at which the heat storage unit 149 starts to store cold heat.

[0119] The later the end point of the second period is, the later the first heat medium from which hot heat or cold heat has been recovered in the first adsorption device 121 and the second adsorption device 122 will finish flowing into the heat storage unit 149. As shown in Fig. 4, the later the first heat medium from which hot heat has been recovered finishes flowing into the heat storage unit 149, the lower the temperature of the first heat medium at which the heat storage unit 149 will finish storing the hot heat. Similarly, the later the first heat medium from which cold heat has been recovered finishes flowing into the heat storage unit 149, the higher the temperature of the first heat medium at which the heat storage unit 149 will finish storing the cold heat.

[0120] As a result, by advancing the start point of the second period and / or delaying the end point of the second period, the amount of heat or cold stored in the heat storage section 149 decreases.

[0121] Similarly, the higher the target value of the amount of hot or cold heat stored in the heat storage unit 149, the later the timing at which the second bypass valve 214 is closed, thereby delaying the start of the second period, and / or the earlier the timing at which the second bypass valve 214 is opened, thereby advancing the end of the second period.

[0122] The later the start point of the second period, the later the first heat medium that has recovered hot heat or cold heat in the first adsorption device 121 and the second adsorption device 122 starts to flow into the heat storage unit 149. As shown in Fig. 4, the later the first heat medium that has recovered hot heat starts to flow into the heat storage unit 149, the higher the temperature of the first heat medium is at which the heat storage unit 149 starts to store hot heat. Similarly, the later the first heat medium that has recovered cold heat starts to flow into the heat storage unit 149, the lower the temperature of the first heat medium is at which the heat storage unit 149 starts to store cold heat.

[0123] The earlier the second period ends, the earlier the first heat medium that has recovered hot heat or cold heat in the first adsorption device 121 and the second adsorption device 122 finishes flowing into the heat storage unit 149. As shown in Fig. 4, the earlier the first heat medium that has recovered hot heat finishes flowing into the heat storage unit 149, the higher the temperature of the first heat medium that the heat storage unit 149 finishes storing the hot heat. Similarly, the earlier the first heat medium that has recovered cold heat finishes flowing into the heat storage unit 149, the lower the temperature of the first heat medium that the heat storage unit 149 finishes storing the cold heat.

[0124] As a result, by delaying the start point of the second period and / or advancing the end point of the second period, the amount of heat or cold stored in the heat storage section 149 increases.

[0125] Therefore, the refrigeration device 100 can adjust the amount of hot or cold heat stored in the heat storage unit 149 by changing the timing at which the second bypass valve 214 is closed and the timing at which the second bypass valve 214 is opened.

[0126] - Second embodiment - The basic configuration and operation of the refrigeration device 100 of the second embodiment are the same as those of the refrigeration device 100 of the first embodiment. The main difference between the refrigeration device 100 of the second embodiment and the refrigeration device 100 of the first embodiment is the utilization side circuit 102.

[0127] In this embodiment, the utilization side circuit 102 does not have the third fluid pump 145, the second on-off valve 146, the heat storage unit 149, or the second heat medium flow path 114. As shown in Fig. 5 , the utilization side circuit 102 has a first heat exchanger 142 provided in the first heat medium flow path 112 at a position where the heat storage unit 149 would be provided in the first embodiment.

[0128] The first heat medium flow path 112 connects the first fluid pump 141, the first on-off valve 144, the first heat exchanger 142, the first adsorption device 121, the second fluid pump 151, the second heat exchanger 152, the second adsorption device 122, and the flow path change units 156-159.

[0129] The second bypass flow path 213 bypasses the first heat exchanger 142 in the first heat medium flow path 112. The second bypass flow path 213 connects, in the first heat medium flow path 112, the flow path between the first fluid pump 141 and the first on-off valve 144 and the flow path between the first heat exchanger 142 and the flow path changing unit 156.

[0130] 6, in this embodiment, the control unit 105 does not control the third fluid pump 145 and the second on-off valve 146. The control unit 105 controls the first bypass valve 212 and the second bypass valve 214 in the same manner as in the first embodiment.

[0131] In the refrigeration device 100 of this embodiment, the hot or cold energy recovered by the first heat medium in the first adsorption device 121 and the second adsorption device 122 is utilized by being heat exchanged with air in the first heat exchanger 142.

[0132] -Variation- (1) Variation A (1-1) Configuration of the Refrigeration Device 100 The basic configuration and operation of the refrigeration device 100 of this modified example are the same as those of the refrigeration device 100 of the first embodiment. The main difference between the refrigeration device 100 of this modified example and the refrigeration device 100 of the first embodiment is the heat source side circuit 101.

[0133] 7, the heat source side circuit 101 further includes a first pressure vessel 171, a second pressure vessel 172, a first valve 191, and a second valve 192. The first pressure vessel 171, the second pressure vessel 172, the first valve 191, and the second valve 192 are further connected to the refrigerant flow path 111.

[0134] The first pressure vessel 171 is connected to the discharge side of the compressor 131. The first pressure vessel 171 is provided in the refrigerant flow path 111 between the discharge side of the compressor 131 and the switching mechanism 135.

[0135] The second pressure vessel 172 is connected to the suction side of the compressor 131. The second pressure vessel 172 is provided in the refrigerant flow path 111 between the suction side of the compressor 131 and the switching mechanism 135.

[0136] The first pressure vessel 171 and the second pressure vessel 172 are vessels having an inlet and an outlet for the refrigerant. During operation of the refrigeration apparatus 100, the first pressure vessel 171 and the second pressure vessel 172 contain a refrigerant therein that flows through the refrigerant flow path 111. During operation of the refrigeration apparatus 100, the first pressure vessel 171 contains a high-pressure refrigerant therein. During operation of the refrigeration apparatus 100, the second pressure vessel 172 contains a low-pressure refrigerant therein.

[0137] The first valve 191 and the second valve 192 are, for example, electromagnetic valves. The first valve 191 and the second valve 192 are attached to a pipe in the refrigerant flow path 111 through which the refrigerant flows.

[0138] When the refrigerant flow path 111 is in a first state, the first valve 191 allows or blocks the flow of refrigerant between the first pressure vessel 171 and the first adsorber 121. When the refrigerant flow path 111 is in a second state, the first valve 191 allows or blocks the flow of refrigerant between the first pressure vessel 171 and the second adsorber 122.

[0139] When the refrigerant flow path 111 is in the first state, the second valve 192 allows or blocks the flow of refrigerant between the second pressure vessel 172 and the second adsorber 122. When the refrigerant flow path 111 is in the second state, the second valve 192 allows or blocks the flow of refrigerant between the second pressure vessel 172 and the first adsorber 121.

[0140] 8, the control unit 105 further controls the first valve 191 and the second valve 192. The control unit 105 controls the opening and closing of the first valve 191 and the second valve 192 to allow or block the flow of refrigerant between the first adsorber 121, the second adsorber 122, the first pressure vessel 171, and the second pressure vessel 172.

[0141] (1-2) Features While the refrigerant flow path 111 is in the first state, the first pressure vessel 171 communicates with the first adsorption device 121, and the second pressure vessel 172 communicates with the second adsorption device 122. Therefore, a high-pressure refrigerant is present in the first space 164a of the first adsorption device 121, and a low-pressure refrigerant is present in the first space 164a of the second adsorption device 122.

[0142] While the refrigerant flow path 111 is in the second state, the first pressure vessel 171 communicates with the second adsorption device 122, and the second pressure vessel 172 communicates with the first adsorption device 121. Therefore, a low-pressure refrigerant is present in the first space 164a of the first adsorption device 121, and a high-pressure refrigerant is present in the first space 164a of the second adsorption device 122.

[0143] The third period is shortened by the high-pressure refrigerant in the first pressure vessel 171 and the low-pressure refrigerant in the second pressure vessel 172. The third period is the period from the time when the refrigerant flow path 111 switches between the first state and the second state to the time when the pressure in the first space 164a of the first adsorption device 121 and the second adsorption device 122 reaches the adsorption pressure or the desorption pressure.

[0144] During a third period after the refrigerant flow path 111 switches from the first state to the second state, the pressure in the first space 164a of the second adsorber 122 is lower than the adsorption pressure, and therefore hot heat is not recovered by the first heat medium in the second space 164b of the second adsorber 122. Furthermore, during a third period after the refrigerant flow path 111 switches from the first state to the second state, the pressure in the first space 164a of the first adsorber 121 is higher than the desorption pressure, and therefore cold heat is not recovered by the first heat medium in the second space 164b of the first adsorber 121. Therefore, the shorter the third period, the shorter the period during which the first heat medium flowing through the first heat medium flow path 112 cannot recover hot heat and cold after the refrigerant flow path 111 switches between the first state and the second state. In other words, the shorter the third period is, the more efficiently the first adsorption device 121 and the second adsorption device 122 recover the hot energy and the cold energy by the first heat medium.

[0145] Furthermore, by closing first valve 191 and second valve 192 for a predetermined time, control unit 105 can increase the pressure of the refrigerant in first pressure vessel 171 and decrease the pressure of the refrigerant in second pressure vessel 172, compared to when first valve 191 and second valve 192 are not closed. This shortens the third period, and allows the heat medium to recover hot and cold energy more efficiently.

[0146] Therefore, the refrigeration device 100 of this modified example can efficiently utilize the hot heat generated when the refrigerant is adsorbed onto the adsorbent 181 and the cold heat generated when the refrigerant is desorbed onto the adsorbent 181, compared to when the heat source side circuit 101 does not have the first pressure vessel 171 and the second pressure vessel 172.

[0147] This modification is applicable to Embodiment 2. In other words, in the refrigeration apparatus 100 of the second embodiment, the heat source side circuit 101 may further include a first pressure vessel 171 and a second pressure vessel 172.

[0148] (2) Variation B In the first embodiment, the control unit 105 switches the refrigerant flow path 111 between the first state and the second state while pressure equalization is being performed by temporarily opening the first bypass valve 212. In other words, the control unit 105 controls the switching mechanism 135 to switch the refrigerant flow path 111 at a predetermined time after the first bypass valve 212 is opened.

[0149] Switching mechanism 135 has a high-pressure flow path through which a high-pressure refrigerant passes and a low-pressure flow path through which a low-pressure refrigerant passes. In order for control unit 105 to control switching mechanism 135 to switch refrigerant flow path 111, a first differential pressure, which is the difference between the pressure in the high-pressure flow path and the pressure in the low-pressure flow path, must be equal to or greater than a predetermined first value. Once pressure equalization begins, the first differential pressure gradually decreases and falls below the first value. Therefore, control unit 105 controls switching mechanism 135 to switch refrigerant flow path 111 from the time when first bypass valve 212 is opened to start pressure equalization until the time when the first differential pressure falls below the first value.

[0150] The control unit 105 may open the first bypass valve 212 and simultaneously control the switching mechanism 135 to switch the refrigerant flow path 111. In this case, the first differential pressure exceeds the first value.

[0151] The control unit 105 may control the switching mechanism 135 to switch the refrigerant flow path 111 at a time point a predetermined period before the time point at which the first bypass valve 212 is opened. In this case, in FIG. 4 , the control unit 105 controls the switching mechanism 135 to switch the refrigerant flow path 111 during periods P2 and P4. Near the end of periods P2 and P4, the adsorbents 181 of the first adsorption device 121 and the second adsorption device 122 hardly adsorb or desorb refrigerant, and therefore no adsorption heat or desorption heat is generated. Therefore, near the end of periods P2 and P4, the amount of hot or cold recovered by the first heat medium in the first adsorption device 121 and the second adsorption device 122 is substantially zero. In this case, the control unit 105 can control the switching mechanism 135 to switch the refrigerant flow path 111 during periods P2 and P4.

[0152] (3) Variation C The adsorbent used in the refrigeration device 100 is a metal-organic framework. However, materials other than the metal-organic framework may also be used as the adsorbent. Examples of materials other than the metal-organic framework include activated carbon, zeolite-based materials, silica-based materials, and alumina-based materials.

[0153] Although the embodiments of the present disclosure have been described above, it will be understood that various changes in form and details can be made without departing from the spirit and scope of the present disclosure as defined in the claims. [Explanation of symbols]

[0154] 100: Refrigeration equipment 101: Heat source side circuit 102:Using circuit 105: Control unit 111: refrigerant flow path 112: First heat medium flow path 114: Second heat transfer medium flow path 121: 1st adsorption device 122:Second adsorption device 131: Compressor 135: Switching mechanism 142: 1st heat exchanger (heat exchanger) 149: Heat storage part 181: Adsorbent 211: First bypass flow path 212: First bypass valve (first valve) 213: Second bypass flow path 214: Second bypass valve (second valve) [Prior art documents] [Patent documents]

[0155] [Patent Document 1] US Patent Application Publication No. 2023 / 0417459

Claims

1. a heat source side circuit (101) having a compressor (131), a first adsorption device (121), a second adsorption device (122), a switching mechanism (135), and a refrigerant flow path (111) through which a refrigerant flows; a utilization side circuit (102) having a first heat medium flow path (112) through which a first heat medium flows; A control unit (105); Equipped with The compressor draws in and compresses a low-pressure refrigerant and discharges it as a high-pressure refrigerant, The first adsorption device and the second adsorption device have an adsorbent (181) that adsorbs and desorbs a refrigerant in accordance with a change in the pressure of the refrigerant, and hot heat generated when the adsorbent adsorbs the refrigerant and cold heat generated when the adsorbent desorbs the refrigerant are recovered, The switching mechanism switches the refrigerant flow path a first state in which a discharge side of the compressor and the first adsorber are connected to each other to create a high-pressure state inside the first adsorber, and a suction side of the compressor and the second adsorber are connected to each other to create a low-pressure state inside the second adsorber; a second state in which the suction side of the compressor and the first adsorber are connected to each other to create a low-pressure state inside the first adsorber, and the discharge side of the compressor and the second adsorber are connected to each other to create a high-pressure state inside the second adsorber; and can be switched between the first adsorption device recovers the hot heat by the first heat medium when the refrigerant flow path is in the first state, and recovers the cold heat by the first heat medium when the refrigerant flow path is in the second state; the second adsorption device recovers the cold heat by the first heat medium when the refrigerant flow path is in the first state, and recovers the hot heat by the first heat medium when the refrigerant flow path is in the second state; The heat source side circuit includes: a first bypass flow path (211) connecting the first adsorber and the second adsorber without passing through the compressor; a first valve (212) provided in the first bypass flow path; and The utilization side circuit is a utilization unit that utilizes the heat of the first heat medium; a second bypass flow path (213) that bypasses the utilization section; a second valve (214) provided in the second bypass flow path; and The control unit opening the first valve for a first period of time; controlling the switching mechanism to switch between the first state and the second state at a time point a predetermined time before the start of the first period, simultaneously with the start of the first period, or at a time point a predetermined time after the start of the first period; closing the second valve for a second period of time; The first period at least partially overlaps with the second period. A refrigeration device (100).

2. The control unit starts the second period simultaneously with the start of the first period, or starts the second period during the first period. The refrigeration system of claim 1.

3. the control unit ends the second period after the first period ends and before switching between the first state and the second state.

3. The refrigeration system according to claim 1 or 2.

4. the control unit causes the start time of the second period when a target value of the amount of heat utilized in the utilization unit is a first amount of heat to be later than the start time of the second period when the target value is a second amount of heat that is lower than the first amount of heat.

3. The refrigeration system according to claim 1 or 2.

5. the control unit causes the second period to end earlier when a target value of the amount of heat utilized by the utilization unit is a third amount of heat than when the target value is a fourth amount of heat that is lower than the third amount of heat.

3. The refrigeration system according to claim 1 or 2.

6. The utilization unit includes a heat exchanger (142) provided in the first heat medium flow path.

3. The refrigeration system according to claim 1 or 2.

7. The utilization unit includes: a second heat medium flow path (114) through which a second heat medium flows; a heat exchanger (142) provided in the second heat medium flow path; a heat storage unit (149) provided in the first heat medium flow path and the second heat medium flow path, and in which the hot heat or the cold heat recovered by the first heat medium is recovered into the second heat medium; Including, 3. The refrigeration system according to claim 1 or 2.

8. The adsorbent includes a metal organic framework including a metal ion and an organic ligand.

3. The refrigeration system according to claim 1 or 2.

9. The refrigerant flowing through the refrigerant flow path is selected from the group consisting of carbon dioxide, hydrocarbon refrigerants, ammonia, and water.

3. The refrigeration system according to claim 1 or 2.

Images