Heat supply device

Abstract

The invention relates to a heat supply device. A heat supply device according to the present invention comprises: a compressor that compresses a refrigerant; a first heat exchanger that exchanges heat between the air and the refrigerant; a second heat exchanger that exchanges heat between the water and the refrigerant; a conversion valve for conveying the refrigerant discharged from the compressor to the first heat exchanger or the second heat exchanger; a third heat exchanger that exchanges heat between the refrigerant flowing through a liquid pipe connecting the first heat exchanger and the second heat exchanger and the refrigerant branched from the liquid pipe and expanded; a first expansion valve that expands the refrigerant flowing in the direction from the third heat exchanger to the first heat exchanger; and a second expansion valve that expands the refrigerant flowing in the direction from the third heat exchanger to the second heat exchanger. The first expansion valve and the second expansion valve can be selectively opened and closed according to the direction of the refrigerant flowing in the third heat exchanger, so that the refrigerant passing through the third heat exchanger flows in the first expansion valve or the second expansion valve.

Description

Technical Field

[0001] The present invention relates to a heat supply device, and more particularly to a heat supply device that uses a refrigerant discharged from a compressor to heat or cool water flowing into an indoor space. Background Art

[0002] The heat supply device may refer to a device that supplies heat energy or cold energy to water flowing into the indoor space.

[0003] The heat supply device may have a structure including a compressor, a first heat exchanger for heat exchange between air and refrigerant, and a second heat exchanger for heat exchange between water supplied to the room and the refrigerant. That is, the heat supply device may use an air source heat pump water heater (AWHP) device that uses a refrigerant to heat exchange between air and water. The water flowing in the second heat exchanger for heat exchange between water and refrigerant may receive cold energy or heat energy from the refrigerant and be supplied to the indoor space.

[0004] The heat supply device may be operated in a heating operation mode in which high-pressure refrigerant is mainly supplied to the second heat exchanger, but may also be operated in a cooling operation mode in which liquid refrigerant is supplied to the second heat exchanger according to conditions.

[0005] There is a capacity difference between the first heat exchanger for heat exchange between air and refrigerant and the second heat exchanger for heat exchange between water and refrigerant. Mainly, the capacity of the first heat exchanger is formed to be larger than the capacity of the second heat exchanger. Therefore, when the heat supply device performs the heating operation mode and the cooling operation mode, problems caused by the flow difference of the refrigerant occur.

[0006] In addition, the heat supply device may include an expansion valve and a supercooling device for improving heat exchange performance in the liquid pipe connecting the first heat exchanger and the second heat exchanger. The refrigerant that has passed through the supercooling device passes through the expansion valve, which is beneficial to performance, but in the case of including an expansion valve and a supercooling device, there is a problem that performance can be improved only in one operation mode of the heating operation mode and the cooling operation mode.

[0007] Korean patent publication KR10-2022-0043958A also discloses a structure in which only one expansion device and one subcooler are arranged in the liquid pipe. Summary of the invention

[0008] The problem to be solved by the present invention is to provide a heat supply device capable of ensuring performance during cooling.

[0009] Still another object of the present invention is to provide a heat supply device capable of adjusting the flow rate of a refrigerant that changes according to a cooling operation mode and a heating operation mode.

[0010] Problems of the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

[0011] In order to solve the above problems, the heat supply device of the embodiment of the present invention includes: a compressor, which compresses refrigerant; a first heat exchanger, which exchanges heat between air and refrigerant; a second heat exchanger, which exchanges heat between water and refrigerant; a conversion valve, which delivers the refrigerant discharged from the compressor to the first heat exchanger or the second heat exchanger; a third heat exchanger, which exchanges heat between the refrigerant flowing in the liquid pipe connecting the first heat exchanger and the second heat exchanger and the refrigerant branched from the liquid pipe and expanded; a first expansion valve, which expands the refrigerant flowing from the third heat exchanger to the first heat exchanger; and a second expansion valve, which expands the refrigerant flowing from the third heat exchanger to the second heat exchanger. The first expansion valve and the second expansion valve are selectively opened and closed according to the direction of the refrigerant flowing in the third heat exchanger, so that the refrigerant passing through the third heat exchanger can flow in the first expansion valve or the second expansion valve.

[0012] The liquid pipe includes: a first liquid pipe, configured with the third heat exchanger and the first expansion valve; a second liquid pipe, configured with the second expansion valve; and a bypass pipe, connecting one side of the first liquid pipe and the other side of the first liquid pipe, the second liquid pipe and the bypass pipe are respectively connected in parallel with the first liquid pipe at different positions.

[0013] The first liquid pipe is provided with a first check valve for conveying the refrigerant flowing in the bypass pipe to the third heat exchanger, so that the refrigerant bypassing the first expansion valve can flow to the second expansion valve via the third heat exchanger.

[0014] The first expansion valve and the third heat exchanger are arranged between the two ends of the bypass pipe connected to the first liquid pipe, and the third heat exchanger and the first check valve are arranged between the two ends of the second liquid pipe connected to the first liquid pipe, so that the refrigerant flowing from the bypass pipe can flow in one direction.

[0015] The first check valve causes the refrigerant to flow toward the third heat exchanger, so that the refrigerant flowing from the bypass pipe can flow to the third heat exchanger.

[0016] The bypass pipe is provided with a second check valve for conveying the refrigerant flowing through the first heat exchanger to the third heat exchanger, thereby preventing the refrigerant flowing through the first liquid pipe to the third heat exchanger from flowing to the bypass pipe.

[0017] The bypass pipe is connected to the first liquid pipe to bypass the first expansion valve and the third heat exchanger so that the refrigerant flowing from the first heat exchanger can flow through the first expansion valve.

[0018] The second liquid pipe is connected to the first liquid pipe to bypass the third heat exchanger and the first check valve, so that the refrigerant flowing through the third heat exchanger can flow to the second liquid pipe and pass through the second expansion valve.

[0019] The heat exchanger may further include: a branch pipe branching from the liquid pipe and allowing the refrigerant to flow to the third heat exchanger; and a third expansion valve disposed on the branch pipe and causing the flowing refrigerant to expand, thereby reducing the temperature of the refrigerant flowing in the liquid pipe.

[0020] The branch pipe branches from the liquid pipe at a position between the third heat exchanger and the first expansion valve.

[0021] The refrigerant flowing toward the third heat exchanger through the branch pipe may be supplied to the compressor.

[0022] The second expansion valve may have a larger diameter than the first expansion valve, thereby increasing the amount of refrigerant flowing from the first heat exchanger to the second heat exchanger.

[0023] The heat supply device operates in a heating operation mode for delivering the refrigerant discharged from the compressor to the second heat exchanger. In the heating operation mode, the second expansion valve is locked so that the refrigerant flowing from the second heat exchanger to the first heat exchanger passes through the first expansion valve after passing through the third heat exchanger, so that in the heating mode, the refrigerant flowing in the liquid pipe can be cooled by the third heat exchanger and then pass through the first expansion valve.

[0024] The heat supply device can be operated in a refrigeration operation mode in which the refrigerant discharged from the compressor is transported to the first heat exchanger. In the refrigeration operation mode, the first expansion valve is locked so that the refrigerant flowing from the first heat exchanger to the second heat exchanger passes through the second expansion valve after passing through the third heat exchanger, so that in the refrigeration mode, the refrigerant flowing in the liquid pipe can be cooled by the third heat exchanger and then pass through the second expansion valve.

[0025] The liquid pipe includes: a first liquid pipe, configured with the third heat exchanger and the first expansion valve; a second liquid pipe, configured with the second expansion valve; and a bypass pipe, connecting one side of the first liquid pipe and the other side of the first liquid pipe. In the refrigeration operation mode, the first expansion valve is locked so that the refrigerant flowing from the first heat exchanger to the second heat exchanger flows to the third heat exchanger through the bypass pipe, and the refrigerant flowing from the third heat exchanger flows through the second liquid pipe, so that in the refrigeration mode, the refrigerant flowing in the liquid pipe can be cooled by the third heat exchanger and then pass through the second expansion valve.

[0026] The first expansion valve can be arranged between the first heat exchanger and the third heat exchanger, the second expansion valve can be arranged between the second heat exchanger and the third heat exchanger, and the heat supply device may include: a first bypass pipe bypassing the first expansion valve; a second bypass pipe bypassing the second expansion valve; a first bypass valve arranged in the first bypass pipe; and a second bypass valve arranged in the second bypass pipe.

[0027] The first expansion valve and the first bypass valve are selectively opened, and the second expansion valve and the second bypass valve are selectively opened, so that the refrigerant passing through the third heat exchanger can pass through the first expansion valve or the second expansion valve.

[0028] Details of other embodiments are included in the detailed description and accompanying drawings.

[0029] According to the heat supply device of the present invention, one or more of the following effects can be achieved.

[0030] First, regardless of the flow direction of the refrigerant flowing in the liquid pipe, the refrigerant passes through the first expansion valve or the second expansion valve after passing through the third heat exchanger, thereby having an advantage of being able to improve heat exchange performance.

[0031] Secondly, there is also an advantage that the flow rate of the refrigerant flowing from the first heat exchanger to the second heat exchanger and the flow rate of the refrigerant flowing from the second heat exchanger to the first heat exchanger can be adjusted by making the first expansion valve and the second expansion valve have different diameters.

[0032] The effects of the present invention are not limited to the above-mentioned effects, and those skilled in the art can clearly understand other effects not mentioned through the description of the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a system diagram of the heat supply device according to the first embodiment of the present invention.

[0034] Figure 2 It is used to illustrate Figure 1FIG. 1 is a diagram showing the flow of refrigerant when the heat supply device is in the heating mode.

[0035] Figure 3 It is used to illustrate Figure 1 A diagram of the flow of refrigerant when the heat supply device is in cooling mode.

[0036] Figure 4 It is a system diagram of a heat supply device according to a comparative example of the present invention.

[0037] Figure 5 This is a graph comparing the cooling performance of the heat supply device of the present invention and the heat supply device of a comparative example of the present invention.

[0038] Figure 6 1 is a flowchart showing a control method of a heat supply device according to the present invention.

[0039] Figure 7 It is a system diagram of a heat supply device according to a second embodiment of the present invention.

[0040] Description of Reference Numerals

[0041] 10: Compressor

[0042] 12: Switching valve

[0043] 20: First heat exchanger

[0044] 22: Heat exchanger fan

[0045] 24: Second heat exchanger

[0046] 30: liquid pipe

[0047] 32: First liquid pipe

[0048] 34: Second liquid pipe

[0049] 36: Bypass pipe

[0050] 38: Branch pipe

[0051] 40: First expansion valve

[0052] 42: Second expansion valve

[0053] 44: The third heat exchanger

[0054] 46: The third expansion valve

[0055] 50: First check valve

[0056] 52: Second check valve

[0057] 60: First bypass pipe

[0058] 62: Second bypass pipe

[0059] 64: First bypass valve

[0060] 66: Second bypass valve DETAILED DESCRIPTION

[0061] If with the attached Figure 1 The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail. However, the present invention is not limited to the embodiments disclosed below, and can be implemented in various forms that are different from each other. This embodiment is only provided to fully disclose the present invention and to fully disclose the scope of the invention to those of ordinary skill in the art, and the present invention is defined by the scope of the claims. Throughout the specification, the same reference numerals represent the same constituent elements.

[0062] Hereinafter, the present invention will be described with reference to the accompanying drawings for explaining a heat supply device according to an embodiment of the present invention.

[0063] The heat supply device described in the present invention can supply heat or cold energy to the indoor space. The heat supply device can supply heat or cold energy to the second heat exchanger 24 (see Figure 1 ) supplies high-pressure refrigerant or low-pressure refrigerant to supply heat energy or cold energy to the water flowing into the indoor space.

[0064] Below, refer to Figure 1 , the structure of the outdoor unit configured in the heat supply device is explained.

[0065] The heat supply device includes: a compressor 10 for compressing refrigerant; a first heat exchanger 20 for exchanging heat between the refrigerant discharged from the compressor 10 and air; a second heat exchanger 24 for exchanging heat between the refrigerant discharged from the compressor 10 and water; and a switching valve 12 for transferring the refrigerant discharged from the compressor 10 to the first heat exchanger 20 or the second heat exchanger 24. The heat supply device also includes a heat exchanger fan 22 for forming an air flow toward the first heat exchanger 20.

[0066] The first heat exchanger 20 performs heat exchange between air and refrigerant. Figure 1 The first heat exchanger 20 may include: a plurality of branch refrigerant tubes 21a; a heat exchanger head 21b connecting one side of the plurality of branch refrigerant tubes 21a and a liquid pipe 30 described below; and a manifold 21c connecting the other side of the plurality of branch refrigerant tubes 21a and a gas pipe 18b.

[0067] The heat exchanger fan 22 may form an air flow toward the first heat exchanger 20. Therefore, when the heat exchanger fan 22 is operated, the air flow rate is increased, thereby changing the phase of the refrigerant flowing inside.

[0068] The second heat exchanger 24 exchanges heat between water and refrigerant. A plate-shaped heat exchanger may be used for the second heat exchanger 24. A flow path for water to flow and a flow path for refrigerant to flow are formed inside the second heat exchanger 24. The second heat exchanger 24 may change the phase of the refrigerant by exchanging heat between the refrigerant and water flowing inside.

[0069] The water flowing into the second heat exchanger 24 can flow by a pump (not shown) arranged on one side.

[0070] The switching valve 12 can transfer the refrigerant discharged from the compressor 10 to the first heat exchanger 20 or the second heat exchanger 24. The switching valve 12 can change the flow direction of the refrigerant discharged from the compressor 10 when the operation mode of the heat supply device is changed.

[0071] The heat supply device includes an accumulator 14 that separates the refrigerant flowing toward the compressor 10 and delivers the gas-phase refrigerant to the compressor 10. The heat supply device includes a muffler 16 for reducing the noise of the refrigerant discharged from the compressor 10.

[0072] The heat supply device includes a liquid pipe 30 connecting the first heat exchanger 20 and the second heat exchanger 24 .

[0073] The heat supply device includes a third heat exchanger 44 disposed on the liquid pipe 30 and exchanging heat between the refrigerant flowing in the liquid pipe 30 and the refrigerant branched and expanded from the liquid pipe 30. The refrigerant branched and expanded from the liquid pipe 30 may flow to the compressor 10 after passing through the third heat exchanger 44. The heat supply device includes: a branch pipe 38 that flows from the liquid pipe 30 and causes the refrigerant to flow to the third heat exchanger 44; and a third expansion valve 46 that is disposed on the branch pipe 38 and causes the flowing refrigerant to expand.

[0074] The heat supply device includes a first expansion valve 40 that expands the refrigerant flowing from the third heat exchanger 44 to the first heat exchanger 20. The heat supply device includes a second expansion valve 42 that expands the refrigerant flowing from the third heat exchanger 44 to the second heat exchanger 24.

[0075] The liquid pipe 30 includes: a first liquid pipe 32, provided with a third heat exchanger 44 and a first expansion valve 40; and a second liquid pipe 34, provided with a second expansion valve 42. The liquid pipe 30 includes a bypass pipe 36 connecting one side of the first liquid pipe 32 and the other side of the first liquid pipe 32. The third heat exchanger 44 and the first expansion valve 40 are arranged between respective points of the first liquid pipe 32 connected to both ends of the bypass pipe 36.

[0076] The first liquid pipe 32 connects the first heat exchanger 20 and the second heat exchanger 24. The third heat exchanger 44 is arranged in the first liquid pipe 32. The first expansion valve 40 is arranged in the first liquid pipe 32. The branch pipe 38 branches from one side of the first liquid pipe 32. The branch pipe 38 branches from the first liquid pipe 32 at a position between the third heat exchanger 44 and the first expansion valve 40.

[0077] A first check valve 50 for forming a refrigerant flow from the second heat exchanger 24 to the first heat exchanger 20 is disposed in the first liquid pipe 32. The first check valve 50 is disposed between the second heat exchanger 24 and the third heat exchanger 44.

[0078] Both ends of the second liquid pipe 34 are connected to the first liquid pipe 32. A third heat exchanger 44 is disposed between each point where the first liquid pipe 32 is connected to both ends of the second liquid pipe 34. A first check valve 50 is disposed between each point where the first liquid pipe 32 is connected to both ends of the second liquid pipe 34.

[0079] One end of the second liquid pipe 34 is connected to the first liquid pipe 32 at a position between the first expansion valve 40 and the third heat exchanger 44. The other end of the second liquid pipe 34 is connected to the first liquid pipe 32 at a position between the second heat exchanger 24 and the third heat exchanger 44. The other end of the second liquid pipe 34 is connected to the first liquid pipe 32 at a position between the second heat exchanger 24 and the first check valve 50. Therefore, the refrigerant flowing between the third heat exchanger 44 and the first expansion valve 40 can flow to the second liquid pipe 34 and flow to the second heat exchanger 24 via the second expansion valve 42.

[0080] Both ends of the bypass pipe 36 are connected to the first liquid pipe 32. One end of the bypass pipe 36 is connected to the first liquid pipe 32 at a position between the first expansion valve 40 and the first heat exchanger 20. The other end of the second liquid pipe 34 is connected to the first liquid pipe 32 at a position between the first check valve 50 and the third heat exchanger 44. Therefore, the refrigerant flowing in the bypass pipe 36 can bypass the first expansion valve 40.

[0081] A second check valve 52 for delivering the refrigerant flowing through the first heat exchanger 20 to the third heat exchanger 44 may be disposed in the bypass pipe 36 .

[0082] The heat supply device may include: a high-pressure pipe 18 a through which the refrigerant discharged from the compressor 10 flows; a first air pipe 18 b connecting the switching valve 12 and the first heat exchanger 20 ; and a second air pipe 18 c connecting the switching valve 12 and the second heat exchanger 24 .

[0083] Below, refer to Figure 2 and Figure 3 , describing the flow of the refrigerant and the state of each component when the heat supply device is in the heating operation mode HM and the cooling operation mode CM.

[0084] The heat supply device of the present invention can be operated in a heating operation mode HM or a cooling operation mode CM.

[0085] The heating operation mode HM is an operation method for heating water flowing in the second heat exchanger 24 by sending high-pressure refrigerant to the second heat exchanger 24. The cooling operation mode CM is an operation method for cooling water flowing in the second heat exchanger 24 by sending high-pressure refrigerant to the first heat exchanger 20.

[0086] Reference Figure 2 In the heating operation mode HM, the switching valve 12 delivers the refrigerant discharged from the compressor 10 to the second heat exchanger 24. In the heating operation mode HM, the first expansion valve 40 is adjusted to expand the refrigerant flowing in the liquid pipe 30. In the heating operation mode HM, the second expansion valve 42 is adjusted to prevent the refrigerant from flowing into the second liquid pipe 34.

[0087] In the heating operation mode HM, the first heat exchanger 20 functions as an evaporator. In the heating operation mode HM, the second heat exchanger 24 functions as a condenser.

[0088] Reference Figure 2 , the refrigerant discharged from the compressor 10 may flow to the second heat exchanger 24 and heat the water. The refrigerant flowing from the second heat exchanger 24 flows along the first liquid pipe 32. The refrigerant flowing along the first liquid pipe 32 may be expanded by the first expansion valve 40 after passing through the third heat exchanger 44. The refrigerant passing through the first expansion valve 40 may flow to the first heat exchanger 20 and perform heat exchange with the air.

[0089] The refrigerant flowing from the first heat exchanger 20 may flow to the compressor 10 via the switching valve 12 and the accumulator 14 .

[0090] That is, in the heating operation mode HM, the refrigerant can heat the water flowing in the second heat exchanger 24. In addition, the refrigerant that has passed through the third heat exchanger 44 can flow to the first expansion valve 40. Since the second expansion valve 42 blocks the second liquid pipe 34, the refrigerant does not flow to the second liquid pipe 34. In addition, due to the second check valve 52, the refrigerant flowing in the first liquid pipe 32 does not flow to the bypass pipe 36.

[0091] Reference Figure 3 In the cooling operation mode CM, the switching valve 12 delivers the refrigerant discharged from the compressor 10 to the first heat exchanger 20. In the cooling operation mode CM, the second expansion valve 42 is adjusted to expand the refrigerant flowing in the liquid pipe 30. In the cooling operation mode CM, the first expansion valve 40 is adjusted so that the refrigerant does not flow to the first liquid pipe 32.

[0092] In the cooling operation mode CM, the first heat exchanger 20 functions as a condenser. In the cooling operation mode CM, the second heat exchanger 24 functions as an evaporator.

[0093] Reference Figure 3 The refrigerant discharged from the compressor 10 may flow to the first heat exchanger 20 and heat the air, and may cool the water flowing in the second heat exchanger 24 . The refrigerant flowing from the first heat exchanger 20 flows along the bypass pipe 36 .

[0094] The refrigerant flowing along the bypass pipe 36 flows to the third heat exchanger 44 and flows to the second liquid pipe 34 after heat exchange. The refrigerant flowing along the second liquid pipe 34 may be expanded by the second expansion valve 42. The refrigerant passing through the second expansion valve 42 may flow to the second heat exchanger 24 and exchange heat with water.

[0095] The refrigerant flowing from the second heat exchanger 24 may flow to the compressor 10 via the switching valve 12 and the accumulator 14 .

[0096] That is, in the cooling operation mode CM, the refrigerant can cool the water flowing in the second heat exchanger 24. In addition, the refrigerant that has passed through the third heat exchanger 44 can flow to the second expansion valve 42. Since the first expansion valve 40 blocks the first liquid pipe 32, the refrigerant does not flow to the first liquid pipe 32. In addition, due to the first check valve 50, the refrigerant flowing in the bypass pipe 36 can flow in the direction of the third heat exchanger 44.

[0097] Figure 4 FIG. 2 is a diagram showing a conventional heat supply device. Figure 1 The difference is explained as a benchmark. Figure 4 The heat supply device is provided with only one expansion valve 41. That is, there is no separate structure corresponding to the second expansion valve 42 of the present invention. In addition, Figure 4 The heat supply device does not include the second liquid pipe 34, the bypass pipe 36, the first check valve 50 and the second check valve 52 corresponding to the present invention.

[0098] therefore, Figure 4 The heat supply device can supply the refrigerant having passed through the third heat exchanger 44 to the first heat exchanger 20 via the expansion valve 41 in the heating operation mode HM. Figure 4 The heat supply device has a structure in which the refrigerant expanded by the expansion valve 41 passes through the third heat exchanger 44 in the cooling operation mode CM.

[0099] Reference Figure 5 In the cooling operation mode CM, it can be confirmed that the cooling performance of the present invention is improved. Figure 5In the heat supply device of the present invention, since the refrigerant flowing from the first heat exchanger 20 to the second heat exchanger 24 flows to the second expansion valve 42 after passing through the third heat exchanger 44, the supercooling degree of the liquid refrigerant flowing into the second expansion valve 42 can be increased.

[0100] Reference Figure 5 In the conventional heat supply device B, since the refrigerant flowing from the first heat exchanger 20 to the second heat exchanger 24 flows to the third heat exchanger 44 after passing through the expansion valve 41, the supercooling degree of the refrigerant flowing into the expansion valve 41 is not improved.

[0101] Reference Figure 5 In the heat supply device A of the present invention, since the liquid refrigerant discharged from the first heat exchanger 20 passes through the third heat exchanger 44 and is delivered to the second expansion valve 42, the supercooling degree of the liquid refrigerant can be further ensured. In addition, the specification of the second expansion valve 42 that expands the refrigerant flowing from the first heat exchanger 20 to the second heat exchanger 24 can be different from the specification of the first expansion valve 40 that expands the refrigerant flowing from the second heat exchanger 24 to the first heat exchanger 20. That is, due to the separate specification and control of the second expansion valve 42, the pressure loss at the inlet of the second expansion valve 42 is reduced and the low pressure is slightly increased, so that the suction superheat of the compressor 10 can be optimally maintained.

[0102] <Control>

[0103] Below, refer to Figure 6 , describing the control method of the heat supply device of the present invention.

[0104] When the operation starts, step s100 of selecting a mode and step s200 of driving the compressor 10 are performed.

[0105] Here, in step s100 of selecting a mode, the cooling operation mode CM or the heating operation mode HM may be selected. In step s100 of selecting a mode, the selection may be made by a user.

[0106] In step s200 of driving the compressor 10, the process of compressing and discharging the refrigerant can be performed by operating the compressor 10. Step s200 of driving the compressor 10 and step s100 of selecting the mode can be performed in a reversed order or simultaneously. In step s200 of driving the compressor 10, a pump (not shown) can be operated simultaneously to allow water to flow through the second heat exchanger 24.

[0107] After that, step s300 of adjusting the switching valve 12 may be performed. The switching valve 12 may change the direction of the refrigerant discharged from the compressor 10 according to the selected mode. In the cooling operation mode CM, the switching valve 12 may be adjusted so that the refrigerant discharged from the compressor 10 flows to the first heat exchanger 20. In addition, in the heating operation mode HM, the switching valve 12 may be adjusted so that the refrigerant discharged from the compressor 10 flows to the second heat exchanger 24.

[0108] Unless the operation mode is changed, the switching valve 12 can maintain the direction in which the refrigerant flows.

[0109] Thereafter, step s400 of adjusting the first expansion valve 40 and the second expansion valve 42 is performed to adjust the flow of the refrigerant flowing in the liquid pipe 30 .

[0110] When the air conditioner is in the cooling operation mode CM, the first expansion valve 40 is closed. When the air conditioner is in the heating operation mode HM, the second expansion valve 42 is closed.

[0111] When in the cooling operation mode CM, the second expansion valve 42 may be adjusted. When in the cooling operation mode CM, the second expansion valve 42 may be adjusted to control the discharge superheat.

[0112] When in the heating operation mode HM, the first expansion valve 40 may be adjusted. When in the heating operation mode HM, the first expansion valve 40 may be adjusted to control the discharge superheat.

[0113] Here, the discharge superheat degree may refer to the temperature of the refrigerant discharged from the compressor.

[0114] Thereafter, step s500 may be performed to determine whether the entry condition for controlling the third expansion valve 46 is satisfied.

[0115] Whether the entry condition for controlling the third expansion valve 46 is satisfied can be determined based on the stability of the operation of the heat supply device driven by the compressor 10. As one embodiment, it can be determined whether the condensing temperature is above the first set temperature. When the condensing temperature is above the first set temperature, it can be determined that the entry condition for controlling the third expansion valve 46 is satisfied. As another embodiment, it can be determined whether the discharge superheat of the compressor 10 is above the second set temperature. When the discharge superheat of the compressor 10 is above the second set temperature, it can be determined that the entry condition for controlling the third expansion valve 46 is satisfied.

[0116] When the entry condition for controlling the third expansion valve 46 is satisfied, step s600 of adjusting the third expansion valve 46 is performed.

[0117] In step s600 of adjusting the third expansion valve 46, the first expansion valve 40 or the second expansion valve 42 may be adjusted simultaneously. In step s600 of adjusting the third expansion valve 46, the first expansion valve 40 or the second expansion valve 42 which is not closed may be adjusted simultaneously.

[0118] That is, when in the cooling operation mode CM, the second expansion valve 42 and the third expansion valve 46 can be adjusted simultaneously. In addition, when in the heating operation mode HM, the first expansion valve 40 and the third expansion valve 46 can be adjusted simultaneously.

[0119] When in the cooling operation mode CM, the third expansion valve 46 can be adjusted to control the discharge superheat. The third expansion valve 46 can adjust the amount of refrigerant flowing to the compressor 10 by adjusting the diameter, thereby adjusting the discharge superheat.

[0120] In addition, when in the cooling operation mode CM, the second expansion valve 42 can be adjusted to control the suction superheat. Here, the suction superheat can refer to the temperature of the refrigerant sucked into the compressor. The second expansion valve 42 can adjust the suction superheat of the compressor by adjusting the flow rate of the refrigerant sucked into the compressor 10.

[0121] When in the heating operation mode HM, the third expansion valve 46 can be adjusted to control the discharge superheat. In addition, when in the heating operation mode HM, the first expansion valve 40 can be adjusted to control the outlet supercooling degree of the second heat exchanger 24 used as a condenser.

[0122] Here, controlling the outlet supercooling degree of the second heat exchanger 24 may refer to adjusting the temperature of the refrigerant flowing in the second heat exchanger 24 by adjusting the flow rate of the refrigerant flowing from the second heat exchanger 24 to the first heat exchanger 20 .

[0123] Below, refer to Figure 7 , describes a heat supply device according to another embodiment of the present invention. Figure 1 The composition is explained by the difference in the heat supply device.

[0124] Figure 7 The heat supply device is provided with a first expansion valve 40, a second expansion valve 42 and a third heat exchanger 44 in a liquid pipe 30. In addition, the heat supply device includes: a first bypass pipe 60, bypassing the first expansion valve 40; a second bypass pipe 62, bypassing the second expansion valve 42; a first bypass valve 64, arranged in the first bypass pipe 60; and a second bypass valve 66, arranged in the second bypass pipe 62.

[0125] The heat supply device includes a branch pipe 38 that branches from the liquid pipe 30 and allows the refrigerant to flow to the third heat exchanger 44 , and a third expansion valve 46 that is disposed on the branch pipe 38 and expands the flowing refrigerant.

[0126] The first expansion valve 40 is disposed between the first heat exchanger 20 and the third heat exchanger 44. In the cooling operation mode CM, the first expansion valve 40 is closed, and in the heating operation mode HM, the first expansion valve 40 is opened.

[0127] The second expansion valve 42 is disposed between the second heat exchanger 24 and the third heat exchanger 44. The second expansion valve 42 is opened in the cooling operation mode CM, and is closed in the heating operation mode HM.

[0128] The first expansion valve 40 and the first bypass valve 64 can be selectively opened. That is, when the first expansion valve 40 is opened, the first bypass valve 64 is closed. In addition, when the first expansion valve 40 is closed, the first bypass valve 64 is opened.

[0129] Looking at the opening and closing based on the operation mode, in the cooling operation mode CM, the first expansion valve 40 is closed and the first bypass valve 64 is opened. In addition, in the heating operation mode HM, the first expansion valve 40 is opened and the first bypass valve 64 is closed.

[0130] The second expansion valve 42 and the second bypass valve 66 can be selectively opened. That is, when the second expansion valve 42 is opened, the second bypass valve 66 is closed. In addition, when the second expansion valve 42 is closed, the second bypass valve 66 is opened.

[0131] Looking at the opening and closing based on the operation mode, in the cooling operation mode CM, the second expansion valve 42 is opened and the second bypass valve 66 is closed. In addition, in the heating operation mode HM, the second expansion valve 42 is closed and the second bypass valve 66 is opened.

[0132] In the cooling operation mode CM, looking at the flow of the refrigerant, the refrigerant discharged from the compressor 10 flows to the first heat exchanger 20 through the switching valve 12. The refrigerant passing through the first heat exchanger 20 flows through the first bypass pipe 60 to the third heat exchanger 44. At this time, a part of the refrigerant can flow to the compressor 10 through the branch pipe 38 through the third expansion valve 46 and the third heat exchanger 44.

[0133] The refrigerant passing through the third heat exchanger 44 may expand through the second expansion valve 42 and flow to the second heat exchanger 24, thereby cooling the water flowing in the second heat exchanger 24. Thereafter, the refrigerant discharged from the second heat exchanger 24 may flow to the compressor 10.

[0134] In the heating operation mode HM, looking at the flow of the refrigerant, the refrigerant discharged from the compressor 10 flows through the switching valve 12 to the second heat exchanger 24. In the second heat exchanger 24, water flowing inside can be heated.

[0135] The refrigerant passing through the second heat exchanger 24 flows through the second bypass pipe 62 to the third heat exchanger 44. At this time, a part of the refrigerant may flow through the branch pipe 38, through the third expansion valve 46 and the third heat exchanger 44, and toward the compressor 10.

[0136] The refrigerant having passed through the third heat exchanger 44 is expanded by the first expansion valve 40 and flows toward the first heat exchanger 20 . Then, the refrigerant discharged from the first heat exchanger 20 flows toward the compressor 10 .

[0137] exist Figure 7 In the heat supply device, regardless of the operation mode, the refrigerant flowing in the liquid pipe 30 may pass through the expansion valves 40 and 42 after passing through the third heat exchanger 44. That is, when the refrigerant flows from the first heat exchanger 20 to the second heat exchanger 24, the refrigerant passing through the third heat exchanger 44 may pass through the second expansion valve 42. In addition, when the refrigerant flows from the second heat exchanger 24 to the first heat exchanger 20, the refrigerant passing through the third heat exchanger 44 may pass through the first expansion valve 40.

[0138] Although preferred embodiments of the present invention are illustrated and described above, the present invention is not limited to the above-mentioned specific embodiments, and a person skilled in the art can make various modified implementations without departing from the gist of the present invention as required by the claims, and these modified implementations should not be understood separately from the technical ideas or prospects of the present invention.

Claims

1. A heat supply device, wherein: include: compressor, which compresses the refrigerant; A first heat exchanger for exchanging heat between air and refrigerant; A second heat exchanger for exchanging heat between water and refrigerant; a switching valve for delivering the refrigerant discharged from the compressor to the first heat exchanger or the second heat exchanger; a third heat exchanger for exchanging heat between the refrigerant flowing through the liquid pipe connecting the first heat exchanger and the second heat exchanger and the refrigerant branched from the liquid pipe and expanded; a first expansion valve, for expanding the refrigerant flowing from the third heat exchanger toward the first heat exchanger; as well as The second expansion valve expands the refrigerant flowing from the third heat exchanger to the second heat exchanger. The first expansion valve and the second expansion valve are selectively opened and closed according to a direction of refrigerant flowing through the third heat exchanger.

2. The heat supply device according to claim 1, wherein: The liquid pipe comprises: a first liquid pipe, configured with the third heat exchanger and the first expansion valve; A second liquid pipe, provided with the second expansion valve; a bypass pipe connecting one side of the first liquid pipe and the other side of the first liquid pipe, The second liquid pipe and the bypass pipe are respectively connected in parallel with the first liquid pipe at different positions from each other.

3. The heat supply device according to claim 2, wherein: The first liquid pipe is provided with a first check valve for sending the refrigerant flowing through the bypass pipe to the third heat exchanger.

4. The heat supply device according to claim 3, wherein: The first expansion valve and the third heat exchanger are disposed in the first liquid pipe between both ends of the bypass pipe. The third heat exchanger and the first check valve are arranged in the first liquid pipe between both ends of the second liquid pipe.

5. The heat supply device according to claim 4, wherein: The first check valve causes the refrigerant to flow toward the third heat exchanger.

6. The heat supply device according to claim 5, wherein: The bypass pipe is provided with a second check valve for sending the refrigerant flowing through the first heat exchanger to the third heat exchanger.

7. The heat supply device according to claim 3, wherein: The bypass pipe is connected to the first liquid pipe to bypass the first expansion valve and the third heat exchanger.

8. The heat supply device according to claim 7, wherein: The second liquid pipe is connected in parallel with the first liquid pipe to bypass the third heat exchanger and the first check valve.

9. The heat supply device according to claim 1, wherein: Also includes: a branch pipe that branches from the liquid pipe and allows the refrigerant to flow toward the third heat exchanger; and The third expansion valve is disposed in the branch pipe and expands the flowing refrigerant.

10. The heat supply device according to claim 9, wherein: The branch pipe branches from the liquid pipe at a position between the third heat exchanger and the first expansion valve.

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