A heat pump system capable of flexibly converting heat recovery

Abstract

The present invention discloses a heat pump system capable of flexibly converting heat recovery, comprising a compressor, a heat recovery device, a main four-way reversing valve, a first heat exchanger, a second heat exchanger, a throttling device, a gas-liquid separator, a liquid reservoir, an auxiliary four-way reversing valve and a plurality of one-way valves; wherein the compressor exhaust port, the heat recovery device, the main four-way reversing valve D interface, the C interface, the first heat exchanger, the throttling device, the second heat exchanger, the main four-way reversing valve E interface, the S interface, the gas-liquid separator, and the compressor air intake port are sequentially connected to form a main flow path; the liquid reservoir, the auxiliary four-way reversing valve and the one-way valve constitute a refrigerant auxiliary flow path, which can regulate the refrigerant circulation amount, so that the system can fully cope with the load changes in various working modes regardless of whether it is in the case of heat recovery, enhance reliability, and achieve intelligence. In addition, a heating pipe is arranged on the gas-liquid separator, which further improves the heat pump system, avoids the compressor from being damaged by liquid impact, and enhances the reliability of the system.

Description

Technical Field

[0001] The invention relates to a heat pump system in the fields of refrigeration, heating and sanitary hot water production, in particular to a heat recovery type heat pump system. Background Art

[0002] At present, multifunctional heat pump air conditioning systems are mainly used in the fields of refrigeration, heating, and sanitary hot water production. The known single cooling systems, heat pump hot water systems, and heat recovery heat pump air conditioning systems mainly have the following problems:

[0003] 1. Common heat pump systems have few functions

[0004] Common heat pump systems usually only have two functions: cooling and heating, or even only have a single function of cooling or heating.

[0005] 2. When common heat pump systems with heat recovery meet two or more functional requirements at the same time, they have poor adaptability to load changes, are difficult to achieve intelligence, and are inconvenient to use.

[0006] Common heat pump systems with heat recovery usually have five working modes, namely cooling, heating, production of sanitary hot water, cooling and production of sanitary hot water, and heating and production of sanitary hot water. The heating function is usually used for heating, industrial heat, commercial heat, etc. The sanitary hot water production function is usually used for bathing, swimming pool water, washing, livestock and fishery water, or special hot water in certain industries. In order to achieve the above five working modes, three heat exchangers, namely condenser, evaporator, and full heat recovery device, are usually installed in the system, and two four-way reversing valves are set. The condenser and the heat recovery device are installed in parallel on the system pipeline. The conversion of the condensing heat exchange between the heat recovery device and the condenser is achieved by changing the system working mode and then changing the system flow path through one of the four-way reversing valves. For example, when the system needs the heat recovery device to work (that is, when there is a demand for sanitary hot water), the four-way reversing valve switches the refrigerant flow path so that the refrigerant circulation flow path is connected to the heat recovery device and the flow path connecting to the condenser is blocked. When the system does not need the heat recovery device to work (that is, there is no demand for sanitary hot water), the four-way reversing valve switches the refrigerant flow path again so that the refrigerant circulation flow path is connected to the condenser and the flow path connecting to the heat recovery device is blocked. The other four-way reversing valve is used to switch the refrigerant flow direction between the evaporator and the condenser, which corresponds to the change of the cooling and heating working modes.

[0007] This common heat recovery heat pump system structure determines that it is difficult to realize intelligent function changes between system modes, especially when the system has more than two functional requirements at the same time, such as cooling and sanitary hot water production mode or heating and sanitary hot water production mode. It is difficult to achieve intelligent response to load changes and is inconvenient to use. In either of the above two modes, there are two functional requirement parameters (respectively, cooling temperature and sanitary hot water temperature, or heating temperature and sanitary hot water temperature). For this reason, the control can only be pre-set by manual or system mode to have a priority level for a certain functional requirement parameter. For example, when the heat pump system operates in cooling and sanitary hot water production mode, the two functional requirement parameters are: cooling temperature and sanitary hot water temperature. If the cooling temperature parameter is manually pre-set to have a priority level, the system can only use the cooling temperature with priority as the control parameter of the system operation. When the cooling temperature does not reach the user's set conditions, the heat pump system can simultaneously operate the cooling and sanitary hot water production functions, but when the cooling temperature parameter reaches the user's set conditions, since the cooling temperature parameter has a priority, at this time, regardless of whether the sanitary hot water temperature reaches the user's set conditions, the system will automatically force shutdown. On the contrary, if the user sets the sanitary hot water temperature as having a priority level, a similar problem also exists, that is, the system can only meet the functional requirement parameter condition set as having a priority level, while the other functional requirement parameter condition cannot be met.

[0008] In some cases, in order to meet the conditions of another functional requirement parameter, the user can only achieve this by manually changing the system working mode to the mode corresponding to its function. For example, in the above example, when the refrigeration temperature reaches the user's set conditions, the system will automatically shut down. If the user still wants to meet the sanitary hot water temperature requirements, the system can only rely on manual changes from the original refrigeration and sanitary hot water production mode to the sanitary hot water production mode. The system exits the original mode and re-enters the working procedure of the sanitary hot water production mode. However, there is no refrigeration function in the sanitary hot water production mode, and only the sanitary hot water temperature is used as the control parameter of the system operation, that is, the refrigeration temperature parameter is no longer valid. The sanitary hot water temperature will shut down if it meets the user's set requirements, otherwise it will continue to run. No matter how the refrigeration temperature changes, it will not affect the existing working mode of the system, that is, the system will not automatically switch back to the original refrigeration and sanitary hot water production mode due to changes in the refrigeration temperature. Similarly, the conversion between other modes has similar problems.

[0009] From the above examples, it can be seen that when the common heat recovery heat pump system structure meets two or more functional requirements, it is difficult to achieve intelligent changes between system working modes. The adaptability to load changes is poor, which is inconvenient for users to use and affects the customer's use effect.

[0010] 3. In traditional heat recovery heat pump systems, the system refrigerant circulation volume is different in different working modes, which is prone to refrigerant circulation imbalance problems, affecting the working performance of the heat pump system.

[0011] In common full heat recovery heat pump systems, due to the multiple working modes of the system, the system refrigerant circulation volume is different in different working modes, which easily leads to the problem of unbalanced refrigerant circulation volume, especially when the heat recovery device is put into heat recovery work or not, which will significantly affect the circulation volume of refrigerant in the system. For example, when the heat recovery device is put into use, due to its own good condensation effect, more liquid refrigerant will be retained in the heat recovery device. In this case, the amount of refrigerant involved in the circulation is reduced, and when the heat recovery device is not working, only a small amount of refrigerant will be retained in the heat recovery device. At this time, the amount of refrigerant involved in the refrigerant circulation in the system increases accordingly. In this way, if there is no suitable refrigerant balance structure, the common heat recovery heat pump system is prone to the problem of unbalanced refrigerant circulation volume during operation, thereby affecting the working performance of the heat pump system.

[0012] 4. Common heat recovery heat pump systems have poor reliability

[0013] Common heat recovery heat pump systems have poor adaptability to load changes and low intelligence, and even need to change modes frequently. In addition, the system refrigerant circulation volume is significantly different in different working modes, which easily leads to refrigerant circulation imbalance problems. For this reason, the compressor is very likely to inhale liquid refrigerant during mode conversion and be damaged by liquid shock, resulting in poor system reliability.

[0014] Due to the above-mentioned problems, the heat recovery heat pump system in the known similar technologies has poor adaptability to load changes, is difficult to be intelligent, is inconvenient to use, has unbalanced refrigerant circulation, low reliability and other problems, resulting in many technical obstacles in its promotion and application in some heat pump fields. Summary of the invention

[0015] In order to solve the technical defects of known similar technologies such as few functions, poor adaptability to load changes, low intelligence, frequent manual mode switching, unbalanced refrigerant circulation, poor working performance, low reliability, etc., the present invention specifically provides the following technical solutions:

[0016] A heat pump system capable of flexibly converting heat recovery comprises: a compressor, a heat recovery device, a main four-way reversing valve, a first heat exchanger, a second heat exchanger, a throttling device, and a gas-liquid separator; the main four-way reversing valve is provided with four interfaces D, C, S, and E, and the exhaust port of the compressor is connected to the inlet of the heat recovery device through a pipeline connector, the outlet of the heat recovery device is connected to the D interface of the main four-way reversing valve, the C interface of the main four-way reversing valve is connected to the inlet of the first heat exchanger, the outlet of the first heat exchanger is connected to the inlet of the throttling device, the outlet of the throttling device is connected to the inlet of the second heat exchanger, the outlet of the second heat exchanger is connected to the E interface of the main four-way reversing valve, the S interface of the main four-way reversing valve is connected to the inlet of the gas-liquid separator, and the outlet of the gas-liquid separator is connected to the air intake of the compressor;

[0017] The heat pump system also includes a refrigerant auxiliary flow path mainly used to balance the refrigerant circulation flow, and the refrigerant auxiliary flow path includes: a liquid accumulator, an auxiliary four-way reversing valve and four one-way valves;

[0018] The auxiliary four-way reversing valve has four interfaces, namely, D, C, S, and E. Through pipeline connections, the connecting pipe of the auxiliary four-way reversing valve D interface is plugged into the connecting pipe between the first heat exchanger and the throttling device, the auxiliary four-way reversing valve C interface is connected to the inlet of the liquid reservoir, the auxiliary four-way reversing valve E interface is connected to the outlet of the liquid reservoir, and the connecting pipe of the auxiliary four-way reversing valve S interface is plugged into the connecting pipe between the first heat exchanger and the throttling device;

[0019] The four one-way valves are respectively called the first one-way valve, the second one-way valve, the third one-way valve and the fourth one-way valve; the first one-way valve is installed on the connecting pipe of the auxiliary four-way reversing valve D interface, the outlet end of the first one-way valve is connected to the auxiliary four-way reversing valve D interface, the second one-way valve is installed on the connecting pipe of the auxiliary four-way reversing valve S interface, the inlet end of the second one-way valve is connected to the auxiliary four-way reversing valve S interface, the inlet pipe of the third one-way valve is plugged into the connecting pipe between the throttling device and the second heat exchanger, and the outlet pipe is plugged into the connecting pipe between the auxiliary four-way reversing valve D interface and the first one-way valve, the inlet pipe of the fourth one-way valve is plugged into the connecting pipe between the auxiliary four-way reversing valve S interface and the second one-way valve, and the outlet pipe is plugged into the connecting pipe between the throttling device and the second heat exchanger.

[0020] Furthermore, the heat recovery device is a heat exchanger for heat exchange between refrigerant and water, and its peripheral water channel side also includes an electric valve on the heat recovery device side or a sanitary hot water side water pump. The first heat exchanger and the second heat exchanger are heat exchangers for heat exchange between refrigerant and water or heat exchangers for heat exchange between refrigerant and air; when the first heat exchanger and the second heat exchanger are heat exchangers for heat exchange between refrigerant and water, their peripheral water channel side also includes a first heat exchanger side water pump and a second heat exchanger side water pump; when the first heat exchanger and the second heat exchanger are heat exchangers for heat exchange between refrigerant and air, their air side also includes a first heat exchanger side fan and a second heat exchanger side fan; the electric valve on the heat recovery device side or the sanitary hot water side water pump, the first heat exchanger side water pump, the second heat exchanger side water pump, the first heat exchanger side fan, and the second heat exchanger side fan are configured by the unit itself or are not configured by the unit itself and are installed by the user in the project.

[0021] A controller is set at a suitable position in the heat pump system. The controller and the components in the heat pump system are connected through control lines. The controller is equipped with a preset program and is responsible for managing and controlling the coordinated work of the components in the heat pump system.

[0022] The following briefly describes the working principle of the heat pump system according to the flow of refrigerant in various working modes:

[0023] 1. If the system is set to refrigeration mode or refrigeration and sanitary hot water mode, when the heat pump system of the present invention is working, first, the main four-way reversing valve is in the power-off reset state, and the high-temperature and high-pressure gaseous refrigerant discharged by the compressor first enters the heat recovery device, and then enters the first heat exchanger through the main four-way reversing valve D interface to the C interface. The gaseous refrigerant releases the condensation heat in the heat recovery device and the first heat exchanger and then turns into liquid refrigerant. Then the liquid refrigerant enters the second heat exchanger after passing through the throttling element. The refrigerant absorbs the heat of the external medium in the second heat exchanger and evaporates into a low-temperature and low-pressure gaseous refrigerant, and then passes through the main four-way reversing valve E interface, S interface, and then returns to the compressor through the gas-liquid separator. At this time, the first heat exchanger is used as a condenser and the second heat exchanger is used as an evaporator.

[0024] Moreover, in the cooling and sanitary hot water production mode:

[0025] When the system has the demand for refrigeration and sanitary hot water production, and the refrigeration temperature and the water temperature for producing sanitary hot water have not reached the set conditions, the controller only needs to continuously open the electric valve on the heat recovery side or the water pump on the sanitary hot water side to recover the condensation heat through the heat recovery side and obtain the required sanitary hot water, and continuously open the water pump on the second heat exchanger side or the fan on the second heat exchanger side to obtain the corresponding refrigeration demand, and accordingly, close or reduce the water pump on the first heat exchanger side or the fan on the first heat exchanger side. In this way, the system's condensation heat exchange can be intelligently and smoothly completed between the heat recovery device and the first heat exchanger. The intelligent and flexible conversion, in the mode of refrigeration and sanitary hot water production, realizes the two functions of simultaneous refrigeration and sanitary hot water production;

[0026] When the system has the demand for refrigeration and production of sanitary hot water, and the refrigeration temperature does not reach the set condition, while the water temperature for producing sanitary hot water reaches the set condition, the controller only needs to close the electric valve on the heat recovery device side or the water pump on the sanitary hot water side to stop the condensation heat recovery on the heat recovery device side, and accordingly, start or increase the water pump on the first heat exchanger side or the fan on the first heat exchanger side, and run the water pump on the second heat exchanger side or the fan on the second heat exchanger side, so that the flexible conversion of the condensation heat exchange of the system between the heat recovery device and the first heat exchanger can be completed intelligently and smoothly. In the refrigeration and sanitary hot water production mode, the system realizes the function of only refrigeration;

[0027] When the system has a demand for refrigeration and sanitary hot water production, and the refrigeration temperature reaches the set condition, but the sanitary hot water temperature does not reach the set condition, the controller energizes the main four-way reversing valve, and the main four-way reversing valve is energized and reversed. At this time, the first heat exchanger is used as an evaporator, and the second heat exchanger is used as a condenser. The controller continuously opens the electric valve on the heat recovery side or the water pump on the sanitary hot water side to recover the condensation heat through the heat recovery device to obtain the required sanitary hot water, and turns on the water pump on the first heat exchanger side or the fan on the first heat exchanger side, and accordingly, automatically turns off the water pump on the second heat exchanger side or the fan on the second heat exchanger side; in this way, the system can intelligently and smoothly complete the function of only producing sanitary hot water in the refrigeration and sanitary hot water production mode;

[0028] Through the above working mode, in the same mode of refrigeration and sanitary hot water production, the system can intelligently and smoothly realize the intelligent and flexible conversion of the three situations of simultaneous refrigeration and sanitary hot water production, only refrigeration, and only sanitary hot water production; abandoning the practice of traditional technology that must forcibly change the system working mode to achieve its conversion. It is precisely because the present invention can realize the back and forth change between the two situations of producing sanitary hot water or stopping the production of sanitary hot water without converting the system working mode, thus improving the adaptability and intelligence of the heat recovery heat pump system and its device to load changes;

[0029] In the above working process, whether the heat recovery device participates in the heat recovery work will obviously affect the amount of refrigerant circulating in the system, which may easily cause the refrigerant to run unbalanced, affecting the working performance of the heat pump system. To solve this problem, the refrigerant auxiliary flow path works as follows:

[0030] 1) When the system has the demand for refrigeration and sanitary hot water, and the refrigeration temperature and the water temperature for producing sanitary hot water have not reached the set conditions, the auxiliary four-way reversing valve is electrically reversed, the D interface of the auxiliary four-way reversing valve is connected with the E interface, and the C interface is connected with the S interface. During operation, part of the liquid refrigerant coming out of the first heat exchanger passes through the first one-way valve, the D interface and the E interface of the auxiliary four-way reversing valve, and enters the liquid reservoir from the outlet pipe of the liquid reservoir in the reverse direction, and then passes through the liquid reservoir inlet pipe, the C interface of the auxiliary four-way reversing valve, the S interface and the fourth one-way valve, and finally After that, it merges with the refrigerant from the outlet pipe of the throttling device and flows to the second heat exchanger; 2) When the system has the demand for refrigeration and sanitary hot water production, and the refrigeration temperature reaches the set condition, but the water temperature for producing sanitary hot water does not reach the set condition, the auxiliary four-way reversing valve is electrically reversed, and the D interface of the auxiliary four-way reversing valve is connected with the E interface, and the C interface is connected with the S interface. During operation, part of the liquid refrigerant coming out of the second heat exchanger passes through the third one-way valve, the D interface and the E interface of the auxiliary four-way reversing valve, and enters the liquid reservoir from the outlet pipe of the liquid reservoir in the reverse direction, and then passes through the liquid reservoir The refrigerant flows through the inlet pipe of the receiver, passes through the C interface of the auxiliary four-way reversing valve, the S interface and the second one-way valve, and finally merges with the refrigerant of the outlet pipe of the throttling device and flows to the first heat exchanger; in the above two cases 1) and 2), since the refrigerant flows through the liquid receiver in the reverse direction, the structural characteristics of the liquid receiver with a small amount of reverse flow liquid storage are utilized, and only a small amount of refrigerant remains in the liquid receiver; 3) When the system detects that the sanitary hot water temperature has reached the set condition or the system has no demand for sanitary hot water, the auxiliary four-way reversing valve loses power and resets, and the D interface of the auxiliary four-way reversing valve is connected to the C interface The E interface is connected to the S interface. During operation, part of the liquid refrigerant from the first heat exchanger enters the liquid reservoir in a positive direction through the first one-way valve, the auxiliary four-way reversing valve D interface, the C interface and the liquid reservoir inlet pipe, and then passes through the liquid reservoir outlet pipe, the auxiliary four-way reversing valve E interface, the S interface, the fourth one-way valve, and finally merges with the refrigerant from the throttling device and enters the second heat exchanger. At this time, since the refrigerant flows through the liquid reservoir in a positive direction, the liquid reservoir will store a large amount of refrigerant by utilizing the structural characteristics of the liquid reservoir with a large amount of forward flow storage. Through the above working method, the imbalance problem of the system refrigerant circulation volume being too small due to the large amount of liquid refrigerant accumulated in the heat recovery device when the heat recovery device is put into heat recovery work in the traditional heat recovery heat pump system is solved, and the compressor is prevented from being damaged by liquid shock, and the working performance of the heat recovery system and its adaptability to load changes are improved, ensuring the stable and safe operation of the heat recovery heat pump system.

[0031] 2. If the system is set to heating mode, sanitary hot water production mode or heating and sanitary hot water production mode, when the heat pump system of the present invention is working, the main four-way reversing valve is in the energized state, and the main four-way reversing valve is reversed. At this time, the D interface inside the main four-way reversing valve is connected to the E interface, and the C interface is connected to the S interface. The high-temperature and high-pressure gaseous refrigerant discharged by the compressor first enters the heat recovery device, and then enters the second heat exchanger through the D interface and the E interface of the four-way reversing valve. The gaseous refrigerant releases the condensation heat in the heat recovery device and the second heat exchanger and then turns into a liquid refrigerant. Then the liquid refrigerant enters the first heat exchanger after passing through the throttling element. The refrigerant absorbs the heat of the external medium in the first heat exchanger and turns into a low-temperature and low-pressure gaseous refrigerant. Then it passes through the C interface and the S interface of the main four-way reversing valve and returns to the compressor through the gas-liquid separator. In these three working modes, the first heat exchanger is used as an evaporator and the second heat exchanger is used as a condenser.

[0032] Moreover, in the heating and sanitary hot water production mode:

[0033] When the system has the demand for heating and producing sanitary hot water, and the heating temperature and the water temperature for producing sanitary hot water do not reach the set conditions, the controller only needs to open the electric valve on the heat recovery device side or the water pump on the sanitary hot water side to recover the condensation heat through the heat recovery device to obtain the required sanitary hot water, and continue to open the water pump on the first heat exchanger side or the first heat exchanger side fan, and also start the water pump on the second heat exchanger side or the second heat exchanger side fan; in this way, the system can intelligently and smoothly complete the two functions of heating and producing sanitary hot water in the heating and sanitary hot water production mode;

[0034] When the system has the demand for heating and producing sanitary hot water, and the heating temperature does not reach the set requirements, but the water temperature for producing sanitary hot water reaches the set conditions, the electric valve on the heat recovery side or the water pump on the sanitary hot water side is automatically closed through the controller, and the heat recovery device can stop recovering condensation heat. Accordingly, the water pump on the first heat exchanger side or the fan on the first heat exchanger side is continuously turned on, and the water pump on the second heat exchanger side or the fan on the second heat exchanger side is continuously turned on or increased. In this way, the system's condensation heat exchange can be intelligently and smoothly converted between the heat recovery device and the second heat exchanger, and the system can achieve the function of only heating in the heating and sanitary hot water production mode;

[0035] When the system has the demand for heating and producing sanitary hot water, and the heating temperature reaches the set requirements, but the water temperature for producing sanitary hot water does not reach the set conditions, the controller continuously opens the electric valve on the heat recovery side or the water pump on the sanitary hot water side to recover the condensation heat through the heat recovery side to obtain the required sanitary hot water, and continuously opens the water pump on the first heat exchanger side or the fan on the first heat exchanger side. Correspondingly, the water pump on the second heat exchanger side or the fan on the second heat exchanger side is turned off, so that the system can intelligently and smoothly realize the function of only producing sanitary hot water in the heating and sanitary hot water production mode;

[0036] Through the above-mentioned working method, in the same mode of heating and producing sanitary hot water, the system can intelligently and smoothly realize the flexible conversion among the three situations of simultaneous heating and producing sanitary hot water, only heating, and only producing sanitary hot water under the same mode of heating and producing sanitary hot water. It abandons the practice of traditional technology that must forcibly change the system working mode to realize its conversion. It is precisely because the present invention does not need to switch the system working mode to realize the back and forth change of the two situations of producing sanitary hot water or stopping the production of sanitary hot water. In this way, the adaptability and intelligence of the heat recovery heat pump system and its device to load changes are improved.

[0037] Similarly, in the above working process, whether the heat recovery device participates in the heat recovery work will obviously affect the amount of refrigerant circulating in the system, which may easily lead to the phenomenon of unbalanced refrigerant operation. To solve this problem, the working mode of the refrigerant auxiliary flow path is as follows:

[0038] 1) When the system has a demand for producing sanitary hot water and the water temperature has not reached the set condition, the auxiliary four-way reversing valve is electrically reversed, and the D interface of the auxiliary four-way reversing valve is connected to the E interface, and the C interface is connected to the S interface. During operation, part of the liquid refrigerant from the second heat exchanger passes through the third one-way valve, the D interface and the E interface of the auxiliary four-way reversing valve and the outlet pipe of the liquid accumulator in the reverse direction and enters the liquid accumulator, and then passes through the liquid accumulator inlet pipe, the C interface of the auxiliary four-way reversing valve, the S interface and the second one-way valve, and finally merges with the refrigerant from the outlet pipe of the throttling device and flows to the first heat exchanger. Since the refrigerant flows through the liquid accumulator in the reverse direction, the structural characteristics of the liquid accumulator with a small amount of reverse flow liquid storage are utilized, and only a small amount of refrigerant remains in the liquid accumulator; 2) When the system When the system detects that the sanitary hot water temperature reaches the set condition or the system has no demand for producing sanitary hot water, the auxiliary four-way reversing valve loses power and resets, the D interface of the auxiliary four-way reversing valve is connected to the C interface, and the E interface is connected to the S interface. During operation, part of the liquid refrigerant from the second heat exchanger enters the liquid reservoir in a positive direction through the third one-way valve, the D interface of the auxiliary four-way reversing valve, the C interface and the liquid reservoir inlet pipe, and then passes through the liquid reservoir outlet pipe, the E interface of the auxiliary four-way reversing valve, the S interface, the second one-way valve, and finally merges with the refrigerant from the throttling device and enters the first heat exchanger. At this time, since the refrigerant flows through the liquid reservoir in a positive direction, the liquid reservoir will store a large amount of refrigerant by utilizing the structural design of the liquid reservoir with a large forward flow storage volume;

[0039] Through the above working method, the imbalance problem of the traditional heat recovery heat pump system that when the heat recovery device is put into heat recovery work, the heat recovery device accumulates more liquid refrigerant, resulting in a small amount of system refrigerant circulation, and when the heat recovery device is not put into heat recovery work, the system refrigerant circulation amount is too large is solved, thereby avoiding the situation where the compressor is damaged by liquid shock. In this way, the working performance of the heat recovery system and its adaptability to load changes are improved, ensuring the stable and safe operation of the heat recovery heat pump system.

[0040] Furthermore, the throttling device in the above-mentioned heat pump system can be replaced with a throttling device assembly; the throttling device assembly includes a refrigeration throttling device, a heating throttling device, a fifth one-way valve and a sixth one-way valve; the refrigeration throttling device and the fifth one-way valve are connected in series to form a refrigeration throttling device, the heating throttling device and the sixth one-way valve are connected in series to form a heating throttling device, the refrigeration throttling device and the heating throttling device are connected in parallel to form the throttling device assembly, and the two end interfaces of the throttling device assembly are connected to the connecting pipe between the first heat exchanger and the second heat exchanger. In the heat pump system of the present invention, when working in refrigeration mode, the refrigerant will be throttled by the refrigeration throttling device assembly; when heating, producing only sanitary hot water, or heating and producing sanitary hot water, the refrigerant will be throttled by the heating throttling device assembly. The working method of the remaining parts is the same as the above-mentioned technical solution that only uses throttling devices but not throttling device assemblies.

[0041] Another improved technical solution is to use a throttling component assembly to replace the throttling component. In addition to using the throttling component assembly of the above structure, the connection method needs to be changed as follows: the first one-way valve and the third one-way valve are cancelled, and the connecting pipe of the auxiliary four-way reversing valve D interface is divided into two branches, and the two branches are respectively plugged into the connecting pipe between the refrigeration throttling component and the fifth one-way valve, and the connecting pipe between the heating throttling component and the sixth one-way valve. Under this solution, the working mode of the refrigerant auxiliary flow path will be changed as follows:

[0042] If the system is set to cooling mode or cooling and sanitary hot water production mode, 1) when the system has cooling and sanitary hot water production needs, and the cooling temperature and the water temperature for producing sanitary hot water have not reached the set conditions, the auxiliary four-way reversing valve is in an energized reversing state, the D interface of the auxiliary four-way reversing valve is connected to the E interface, and the C interface is connected to the S interface. During operation, after the liquid refrigerant coming out of the first heat exchanger passes through the fifth one-way valve, part of the refrigerant will pass through the D interface and E interface of the auxiliary four-way reversing valve and the outlet pipe of the liquid reservoir, and enter the liquid reservoir in the reverse direction, and then flow out from the inlet pipe of the liquid reservoir, the C interface of the auxiliary four-way reversing valve, the S interface, and the fourth one-way valve, and then merge with the refrigerant coming out of the refrigeration throttling device and flow to the second heat exchanger; 2) when the system has cooling and sanitary hot water production needs, and the cooling temperature reaches the set conditions, but the water temperature for producing sanitary hot water does not reach the set conditions, the auxiliary four-way reversing valve is energized and reversed, and the auxiliary four-way reversing valve is in an energized reversing state. The D interface of the valve is connected with the E interface, and the C interface is connected with the S interface. During operation, part of the liquid refrigerant coming out of the second heat exchanger passes through the sixth one-way valve, the auxiliary four-way reversing valve D interface, the E interface, and the outlet pipe of the liquid reservoir in the reverse direction into the liquid reservoir, and then passes through the liquid reservoir inlet pipe, the auxiliary four-way reversing valve C interface, the S interface and the second one-way valve, and finally merges with the refrigerant out of the outlet pipe of the heating throttling device and flows to the first heat exchanger; 3) When the temperature of the sanitary hot water reaches the set condition or the system has no demand for producing sanitary hot water, the auxiliary four-way reversing valve is in a power-off reset state. After the liquid refrigerant coming out of the first heat exchanger passes through the fifth one-way valve, part of the refrigerant will pass through the auxiliary four-way reversing valve D interface, the C interface, and the inlet pipe of the liquid reservoir, and then flow out from the outlet pipe of the liquid reservoir, the auxiliary four-way reversing valve E interface, the S interface, and the fourth one-way valve, and merge with the refrigerant coming out of the refrigeration throttling device and flow to the second heat exchanger.

[0043] If the system is set to produce sanitary hot water mode, heating mode or heating and sanitary hot water mode, the first heat exchanger is used as an evaporator and the second heat exchanger is used as a condenser. 1) When the system has a demand for producing sanitary hot water and the water temperature has not reached the set conditions, the auxiliary four-way reversing valve is in an energized reversing state. During operation, after the liquid refrigerant coming out of the second heat exchanger passes through the sixth one-way valve, part of the refrigerant will pass through the auxiliary four-way reversing valve D interface, E interface, and the outlet pipe of the liquid reservoir, and then flow out from the inlet pipe of the liquid reservoir, the auxiliary four-way reversing valve C interface, S interface, and the second one-way valve, and then merge with the refrigerant coming out of the heating throttling device to flow to the first heat exchanger; 2) When the temperature of the sanitary hot water reaches the set conditions or the system has no demand for producing sanitary hot water, The auxiliary four-way reversing valve is in the power-off reset state. During operation, after the liquid refrigerant coming out of the second heat exchanger passes through the sixth one-way valve, part of the refrigerant will pass through the auxiliary four-way reversing valve D interface, C interface, and the inlet pipe of the liquid reservoir and enter the liquid reservoir in the positive direction, and then flow out from the outlet pipe of the liquid reservoir, the auxiliary four-way reversing valve E interface, S interface, and the second one-way valve, and then merge with the refrigerant coming out of the heating throttling device and flow to the first heat exchanger. Except for the differences in the above parts, the improved technical solution and the above-mentioned first technical solution of replacing the throttling device in the heat pump system with a throttling device assembly have the same working method.

[0044] The heat pump systems in the above-mentioned technical solutions all have five working modes, namely, cooling, heating, producing sanitary hot water, cooling and producing sanitary hot water, and heating and producing sanitary hot water. However, in daily life, heat pumps with only cooling system and only heating system are also very common. In these two heat pump systems, if the demand for producing sanitary hot water is also to be achieved at the same time and the principle of the present invention is adopted in the system, a heat recovery device and a refrigerant auxiliary flow path are set, then correspondingly, two heat pump systems with two working modes, namely, cooling mode, cooling and producing sanitary hot water mode or heating mode, heating and producing sanitary hot water mode, can be formed respectively. At this time, it is only necessary to cancel the main four-way reversing valve, the second one-way valve and the third one-way valve in the aforementioned heat recovery heat pump system with a throttling device, and make the following corresponding changes in the connection method: the heat recovery device outlet is connected to the first heat exchanger inlet, the second heat exchanger outlet is connected to the gas-liquid separator inlet, the first one-way valve outlet is directly connected to the auxiliary four-way reversing valve D interface, and the auxiliary four-way reversing valve S interface is directly connected to the fourth one-way valve inlet. At this time, the original cooling system or heating system is equipped with a heat recovery heat pump system after the heat recovery device. When working, the first heat exchanger is always used as a condenser and the second heat exchanger is used as an evaporator. The specific working method is as follows:

[0045] When the system is working, the high-temperature and high-pressure gaseous refrigerant discharged by the compressor first enters the heat recovery device and then enters the first heat exchanger. The gaseous refrigerant releases the condensation heat in the heat recovery device and the first heat exchanger and then turns into liquid refrigerant. Then the liquid refrigerant passes through the throttling device and enters the second heat exchanger. The refrigerant absorbs the heat of the external medium in the second heat exchanger and turns into low-temperature and low-pressure gaseous refrigerant, and then returns to the compressor.

[0046] In this process, when the system has a demand for producing sanitary hot water and the water temperature has not reached the set condition, the controller can open the electric valve or sanitary hot water pump on the heat recovery side to recover the condensation heat through the heat recovery device to obtain the required sanitary hot water, and accordingly, the first heat exchanger side water pump or the first heat exchanger side fan is automatically closed or reduced; when the sanitary hot water temperature has reached the set condition or the system has no demand for producing sanitary hot water, the controller automatically closes the electric valve or sanitary hot water side water pump on the heat recovery device, and the heat recovery device can stop recovering the condensation heat, and accordingly, the first heat exchanger side water pump or the first heat exchanger side fan is automatically opened or increased. In this way, the flexible conversion of the system's condensation heat exchange between the heat recovery device and the first heat exchanger can be completed intelligently and smoothly, abandoning the traditional technology that must forcibly change the system's working mode to achieve its conversion. It is precisely because the back-and-forth change between the two situations of producing sanitary hot water or stopping the production of sanitary hot water can be achieved without changing the system's working mode, thus improving the heat recovery heat pump system's adaptability and intelligence to load changes;

[0047] Similarly, in the above working process, whether the heat recovery device participates in the heat recovery work will affect the amount of refrigerant circulating in the system, and it is also easy to cause the refrigerant to run unbalanced, which needs to be adjusted through the refrigerant auxiliary flow path. For the heat recovery heat pump system with a heat recovery device in the above-mentioned single cooling system or single heating system, the working conditions of the refrigerant auxiliary flow path are similar, and the specific working method is described as follows:

[0048] 1) When the system has a demand for producing sanitary hot water and the water temperature has not reached the set condition, the auxiliary four-way reversing valve is electrically reversed, and the D interface of the auxiliary four-way reversing valve is connected to the E interface, and the C interface is connected to the S interface; during operation, part of the liquid refrigerant coming out of the first heat exchanger enters the liquid reservoir in the reverse direction through the first one-way valve, the D interface of the auxiliary four-way reversing valve, the E interface and the outlet pipe of the liquid reservoir, and then passes through the liquid reservoir inlet pipe, the C interface of the auxiliary four-way reversing valve, the S interface and the fourth one-way valve, and finally merges with the refrigerant out of the throttling device outlet pipe and flows to the second heat exchanger. At this time, since the refrigerant flows through the liquid reservoir in the reverse direction, utilizing the structural characteristics of the liquid reservoir with a small amount of reverse flow liquid storage, only a small amount of refrigerant remains in the liquid reservoir. 2) When the system detects that the sanitary hot water temperature has reached the set condition or the system has no demand for producing sanitary hot water, the auxiliary four-way reversing valve loses power and resets, the D interface of the auxiliary four-way reversing valve is connected to the C interface, and the E interface is connected to the S interface; during operation, part of the liquid refrigerant coming out of the first heat exchanger passes through the first one-way valve, the D interface of the auxiliary four-way reversing valve, the C interface and the liquid reservoir inlet pipe, enters the liquid reservoir in a positive direction, and then passes through the liquid reservoir outlet pipe, the E interface of the auxiliary four-way reversing valve, the S interface and the fourth one-way valve, and finally merges with the refrigerant coming out of the throttling device and enters the second heat exchanger. At this time, since the refrigerant flows through the liquid reservoir in a positive direction, the liquid reservoir will store a larger amount of refrigerant by utilizing the structural characteristics of the liquid reservoir with a larger forward flow liquid storage capacity.

[0049] Through the above working method, the problem of imbalance in the heat recovery heat pump system after the heat recovery device is installed in the single cooling system or the single heating system is solved. When the heat recovery device is put into heat recovery work, the system refrigerant circulation volume is too small due to the accumulation of more liquid refrigerant in the heat recovery device, and when the heat recovery device is not put into heat recovery work, the system refrigerant circulation volume is too large. The situation that the compressor is damaged by liquid shock is avoided. In this way, the working performance of the heat recovery system and its adaptability to load changes are improved, thereby ensuring the stable and safe operation of the heat recovery system.

[0050] Furthermore, in the various heat recovery heat pump systems described above, in order to prevent the compressor from being damaged by liquid impact, a gas-liquid separator heating pipe can be added. The gas-liquid separator heating pipe is installed inside the gas-liquid separator or coiled on the outside of the gas-liquid separator shell. The inlet pipe of the gas-liquid separator heating pipe is plugged into the connecting pipe between the compressor and the heat recovery device through a pipe connector, and the outlet pipe of the gas-liquid separator heating pipe is plugged into the outlet pipe of the heat recovery device; during operation, some high-temperature gaseous refrigerant in the compressor exhaust pipe also enters the gas-liquid separator heating pipe, heats the refrigerant in the gas-liquid separator and then merges with the refrigerant in the outlet pipe of the heat recovery device; the function of the gas-liquid separator heating pipe is to heat the refrigerant in the gas-liquid separator so that it is always in a gaseous state, thereby eliminating the adverse effects on the compressor caused by refrigerant imbalance during operation, ensuring that no liquid refrigerant returns to the compressor in the system, and improving the reliability and safety of the working process of the heat recovery heat pump system.

[0051] Of course, the use of gas-liquid separator heating tubes can be used not only in the above heat pump systems with refrigerant auxiliary flow paths, but also in occasions without refrigerant auxiliary flow paths; it is not only suitable for heat pump systems with five working modes, namely, cooling, heating, sanitary hot water production, cooling and sanitary hot water production, heating and sanitary hot water production, but also suitable for heat recovery heat pump systems after a heat recovery device is installed in a single cooling system or a single heating system. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is an exploded view of the main components of a heat pump system capable of flexibly converting heat recovery according to the present invention.

[0053] Figure 2 This is a schematic diagram of the implementation of Example 1 of a heat pump system capable of flexibly converting heat recovery according to the present invention.

[0054] Figure 3 This is a schematic diagram of the implementation of Example 2 of a heat pump system capable of flexibly converting heat recovery according to the present invention (a throttling element assembly is used instead of a throttling element).

[0055] Figure 4 This is a schematic diagram of the implementation of Example 3 of a heat pump system capable of flexibly converting heat recovery according to the present invention (a throttling device assembly is used instead of a throttling device).

[0056] Figure 5 This is a schematic diagram of the implementation of Embodiment 4 of a heat pump system capable of flexibly converting heat recovery according to the present invention (applicable to a heat recovery heat pump system after a heat recovery device is provided in a cooling-only system or a heating-only system).

[0057] Figure 6 This is a schematic diagram of the implementation of Example 5 of a heat pump system capable of flexibly converting heat recovery according to the present invention (with a gas-liquid separator heating tube).

[0058] Figure 7 This is a schematic diagram of the implementation of Example 6 of a heat pump system capable of flexibly converting heat recovery according to the present invention (with a gas-liquid separator heating tube and without a refrigerant auxiliary flow path).

[0059] In the figure: 1 is a controller; 2 is a compressor, 3 is a heat recovery device, 4 is a main four-way reversing valve, 5 is a first heat exchanger, 6 is a second heat exchanger, 7 is a throttling device, 7-1 is a refrigeration throttling device, 7-2 is a heating throttling device, 8 is a gas-liquid separator, 9 is a liquid storage device, 10 is an auxiliary four-way reversing valve, 11-1 is a first one-way valve, 11-2 is a second one-way valve, 11-3 is a third one-way valve, 11-4 is a fourth one-way valve, 11-5 is a fifth one-way valve, 11-6 is a sixth one-way valve, 12-1 is a sanitary hot water side pump, 12-2 is a first heat exchanger side pump, 12-3 is a second heat exchanger side pump, 13-1 is a first heat exchanger side fan, 13-2 is a second heat exchanger side fan, and 14 is a gas-liquid separator heating pipe.

[0060] Note: In the figure, the first heat exchanger side water pump 12-2 and the first heat exchanger side fan 13-1 may not be used at the same time; the second heat exchanger side water pump 12-3 and the second heat exchanger side fan 13-2 may not be used at the same time. DETAILED DESCRIPTION

[0061] The present invention will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0062] Embodiment 1

[0063] Figure 2 The present invention is a schematic diagram of the implementation principle of a heat pump system embodiment 1 capable of flexibly converting heat recovery, comprising: a compressor 2, a heat recovery device 3, a main four-way reversing valve 4, a first heat exchanger 5, a second heat exchanger 6, a throttling device 7, and a gas-liquid separator 8; the main four-way reversing valve 4 has four interfaces D, C, S, and E, and the compressor exhaust port is connected to the heat recovery device inlet through a pipeline connector, the heat recovery device outlet is connected to the D interface of the main four-way reversing valve, the main four-way reversing valve C interface is connected to the first heat exchanger inlet, the first heat exchanger outlet is connected to the throttling device inlet, the throttling device outlet is connected to the second heat exchanger inlet, the second heat exchanger outlet is connected to the E interface of the main four-way reversing valve, the main four-way reversing valve S interface is connected to the gas-liquid separator inlet, and the gas-liquid separator outlet is connected to the compressor suction port;

[0064] The heat pump system further comprises a refrigerant auxiliary flow path, which comprises: a liquid storage tank 9, an auxiliary four-way reversing valve 10 and four one-way valves;

[0065] The auxiliary four-way reversing valve 10 has four interfaces, namely, D, C, S, and E. Through the pipeline connector, the connecting pipe of the auxiliary four-way reversing valve D interface is plugged into the connecting pipe between the first heat exchanger 5 and the throttling device 7, the C interface of the auxiliary four-way reversing valve is connected to the inlet of the liquid reservoir 9, the E interface of the auxiliary four-way reversing valve is connected to the outlet of the liquid reservoir 9, and the connecting pipe of the auxiliary four-way reversing valve S interface is plugged into the connecting pipe between the first heat exchanger 5 and the throttling device 7;

[0066] The four one-way valves are respectively referred to as the first one-way valve 11-1, the second one-way valve 11-2, the third one-way valve 11-3, and the fourth one-way valve 11-4; the first one-way valve 11-1 is installed on the D interface connecting pipe of the auxiliary four-way reversing valve 10, and the outlet end of the first one-way valve is connected to the D interface of the auxiliary four-way reversing valve, the second one-way valve 11-2 is installed on the S interface connecting pipe of the auxiliary four-way reversing valve 10, and the inlet end of the second one-way valve is connected to the D interface of the auxiliary four-way reversing valve. The S interface of the auxiliary four-way reversing valve is connected, the inlet pipe of the third one-way valve 11-3 is plugged into the connecting pipe between the throttling device 7 and the second heat exchanger 6, and the outlet pipe is plugged into the connecting pipe between the D interface of the auxiliary four-way reversing valve 10 and the first one-way valve 11-1, the inlet pipe of the fourth one-way valve 11-4 is plugged into the connecting pipe between the S interface of the auxiliary four-way reversing valve 10 and the second one-way valve 11-2, and the outlet pipe is plugged into the connecting pipe between the throttling device 7 and the second heat exchanger 6;

[0067] The heat recovery device 3 is a heat exchanger for heat exchange between refrigerant and water, and its peripheral waterway side also includes an electric valve on the heat recovery device side or a sanitary hot water side water pump 12-1; the first heat exchanger 5 and the second heat exchanger 6 are heat exchangers for heat exchange between refrigerant and water or heat exchangers for heat exchange between refrigerant and air. When the first heat exchanger 5 and the second heat exchanger 6 are heat exchangers for heat exchange between refrigerant and water, their peripheral waterway side also includes a first heat exchanger side water pump 12-2 and a second heat exchanger side water pump 12-3; when the first heat exchanger 5 and the second heat exchanger 6 are heat exchangers for heat exchange between refrigerant and air, their air side also includes Including the first heat exchanger side fan 13-1, the second heat exchanger side fan 13-2 (Note: in the figure, for easy understanding and identification, the first heat exchanger side water pump 12-2, the first heat exchanger side fan 13-1; and the second heat exchanger side water pump 12-3, the second heat exchanger side fan 13-2 are drawn and marked at the same time); the electric valve on the heat recovery side or the sanitary hot water side water pump 12-1, the first heat exchanger side water pump 12-2, the second heat exchanger side water pump 12-3, the first heat exchanger side fan 13-1, and the second heat exchanger side fan 13-2 are configured by the unit itself or the unit itself is not configured and installed by the user in the use project.

[0068] A controller 1 is arranged at a suitable position of the heat pump system. The controller 1 is connected to relevant components in the heat pump system through control lines. The controller 1 is equipped with a preset program and is responsible for managing and controlling the coordinated work of various components in the heat pump system.

[0069] The following briefly describes the working principle of the heat pump system according to the flow of refrigerant in various working modes:

[0070] 1. If the system is set to the refrigeration mode or the refrigeration and sanitary hot water production mode, when the heat pump system of the present invention is working, first, the main four-way reversing valve 4 is in the power-off reset state, and the high-temperature and high-pressure gaseous refrigerant discharged by the compressor 2 first enters the heat recovery device 3, and then enters the first heat exchanger 5 through the D interface to the C interface of the main four-way reversing valve 4. The gaseous refrigerant releases the condensation heat in the heat recovery device 3 and the first heat exchanger 5 and then turns into a liquid refrigerant. Then the liquid refrigerant passes through the throttling device 7 and enters the second heat exchanger 6. The refrigerant absorbs the heat of the external medium in the second heat exchanger 6 and evaporates into a low-temperature and low-pressure gaseous refrigerant, and then passes through the E interface and S interface of the main four-way reversing valve 4 and returns to the compressor 2 through the gas-liquid separator 8.

[0071] Moreover, in the cooling and sanitary hot water production mode:

[0072] When the system has a demand for cooling and producing sanitary hot water, and the cooling temperature and the water temperature for producing sanitary hot water have not reached the set conditions, the controller 1 only needs to continuously open the electric valve on the heat recovery device side or the sanitary hot water side water pump 12-1 to recover the condensation heat through the heat recovery device 3 and obtain the required sanitary hot water. Accordingly, the first heat exchanger side water pump 12-2 or the first heat exchanger side fan 13-1 is turned off or reduced, and the second heat exchanger side water pump 12-3 or the second heat exchanger side fan 13-2 is operated to obtain the corresponding cooling demand. In this way, the flexible conversion of the system's condensation heat exchange between the heat recovery device 3 and the first heat exchanger 5 can be completed intelligently and smoothly. In the cooling and sanitary hot water production mode, the system realizes the two functions of simultaneous cooling and sanitary hot water production;

[0073] When the system has a demand for cooling and producing sanitary hot water, and the cooling temperature has not reached the set condition, while the water temperature for producing sanitary hot water reaches the set condition, the controller 1 only needs to close the electric valve on the heat recovery device side or the sanitary hot water side water pump 12-1, and the heat recovery device 3 can stop recovering the condensation heat. Accordingly, the first heat exchanger side water pump 12-2 or the first heat exchanger side fan 13-1 is automatically turned on or increased, and the second heat exchanger side water pump 12-3 or the second heat exchanger side fan 13-2 is operated. In this way, the flexible conversion of the system's condensation heat exchange between the heat recovery device 3 and the first heat exchanger 5 can be completed intelligently and smoothly. In the cooling and sanitary hot water production mode, the system realizes the function of only cooling;

[0074] When the system has a demand for cooling and producing sanitary hot water, and the cooling temperature reaches the set condition, but the sanitary hot water temperature does not reach the set condition, the controller 1 allows the main four-way reversing valve 4 to be electrically reversed. At this time, the first heat exchanger 5 is used as an evaporator, and the second heat exchanger 6 is used as a condenser. The controller 1 opens the electric valve on the side of the heat recovery device 3 or the sanitary hot water side water pump 12-1 to recover the condensation heat through the heat recovery device 3 to obtain the required sanitary hot water, and runs the first heat exchanger side water pump 12-2 or the first heat exchanger side fan 13-1, and accordingly, automatically shuts down the second heat exchanger side water pump 12-3 or the second heat exchanger side fan 13-2; in this way, the system can intelligently and smoothly complete the function of only producing sanitary hot water in the cooling and sanitary hot water production mode.

[0075] Through the above working mode, in the refrigeration and sanitary hot water production mode, the system intelligently and smoothly realizes the flexible conversion of the three situations of refrigeration and sanitary hot water production, only refrigeration, and only sanitary hot water production; abandoning the practice of traditional technology that must forcibly change the system working mode to achieve its conversion. It is precisely because the present invention can realize the back and forth change between the two situations of producing sanitary hot water or stopping the production of sanitary hot water without converting the system working mode, thus improving the adaptability and intelligence of the heat recovery heat pump system and its device to load changes;

[0076] In the above working process, whether the heat recovery device 3 participates in the heat recovery work will obviously affect the amount of refrigerant circulating in the system, which may easily cause the refrigerant to run unbalanced, affecting the working performance of the heat pump system. To solve this problem, the refrigerant auxiliary flow path works as follows:

[0077] 1) When the system has a demand for refrigeration and sanitary hot water production, and the refrigeration temperature and the water temperature for producing sanitary hot water do not reach the set conditions, the auxiliary four-way reversing valve 10 is electrically reversed, and the D interface of the auxiliary four-way reversing valve is connected to the E interface, and the C interface is connected to the S interface. During operation, part of the liquid refrigerant coming out of the first heat exchanger 5 passes through the first one-way valve 11-1, the D interface and the E interface of the auxiliary four-way reversing valve 10, and enters the liquid reservoir from the outlet pipe of the liquid reservoir 9 in the reverse direction, and then passes through the inlet pipe of the liquid reservoir 9, through the C interface and the S interface of the auxiliary four-way reversing valve 10 and the fourth one-way valve 1 1-4, and finally merges with the refrigerant from the outlet pipe of the throttling device 7 and flows to the second heat exchanger 6; 2) When the system has the demand for refrigeration and production of sanitary hot water, and the refrigeration temperature reaches the set condition, but the water temperature for producing sanitary hot water does not reach the set condition, the auxiliary four-way reversing valve 10 is electrically reversed, and the D interface of the auxiliary four-way reversing valve is connected with the E interface, and the C interface is connected with the S interface. During operation, part of the liquid refrigerant coming out of the second heat exchanger 6 passes through the third one-way valve 11-3, the D interface and the E interface of the auxiliary four-way reversing valve, and enters the liquid reservoir from the outlet pipe of the liquid reservoir 9 in the reverse direction, and then passes through the liquid reservoir The refrigerant flows through the inlet pipe of the accumulator, passes through the auxiliary four-way reversing valve C interface, S interface and the second one-way valve 11-2, and finally merges with the refrigerant out of the throttling member 7 and flows to the first heat exchanger 5; in the above-mentioned 1) and 2) cases, since the refrigerant flows through the accumulator in the reverse direction, the structural characteristics of the accumulator with a small amount of reverse flow liquid storage are utilized, and only a small amount of refrigerant remains in the accumulator; 3) When the system detects that the sanitary hot water temperature has reached the set condition or the system has no demand for producing sanitary hot water, the auxiliary four-way reversing valve 10 loses power and resets, the auxiliary four-way reversing valve D interface is connected to the C interface, and the E interface is connected to the C interface. It is connected to the S interface. During operation, part of the liquid refrigerant coming out of the first heat exchanger 5 enters the liquid reservoir in a positive direction through the first one-way valve 11-1, the D interface and the C interface of the auxiliary four-way reversing valve 10 and the inlet pipe of the liquid reservoir 9, and then passes through the outlet pipe of the liquid reservoir 9, the E interface and the S interface of the auxiliary four-way reversing valve 10, the fourth one-way valve 11-4, and finally merges with the refrigerant coming out of the throttling device 7 and enters the second heat exchanger 6; at this time, since the refrigerant flows through the liquid reservoir 9 in a positive direction, the liquid reservoir will store a larger amount of refrigerant by utilizing the structural characteristics of the liquid reservoir with a larger forward flow storage capacity. Through the above-mentioned working method, the imbalance problem of the traditional heat recovery heat pump system that when the heat recovery device 3 is put into heat recovery work, the system refrigerant circulation volume is too small due to the accumulation of more liquid refrigerant in the heat recovery device, and when the heat recovery device 3 is not put into heat recovery work, the system refrigerant circulation volume is too large is solved, the working performance of the unit is improved, and the situation where the compressor is damaged by liquid shock is avoided, the working performance of the heat recovery system and its adaptability to load changes are improved, and the heat recovery heat pump system is ensured to operate stably and safely.

[0078] 2. If the system is set to heating mode, sanitary hot water production mode or heating and sanitary hot water production mode, when the heat pump system of the present invention is working, the main four-way reversing valve 4 is in the power-on reversing state, at this time, the D interface inside the main four-way reversing valve is connected to the E interface, and the C interface is connected to the S interface. The high-temperature and high-pressure gaseous refrigerant discharged by the compressor 2 first enters the heat recovery device 3, and then enters the second heat exchanger 6 through the D interface and the E interface of the main four-way reversing valve 4. The gaseous refrigerant releases heat in the heat recovery device 3 and the second heat exchanger 6 and then turns into liquid refrigerant. Then the liquid refrigerant enters the first heat exchanger 5 after passing through the throttling device 7. The refrigerant absorbs the heat of the external medium in the first heat exchanger 5 and turns into low-temperature and low-pressure gaseous refrigerant, and then passes through the C interface and the S interface of the main four-way reversing valve 4 and returns to the compressor 2 through the gas-liquid separator 8. In these three modes, the first heat exchanger 5 is used as an evaporator and the second heat exchanger 6 is used as a condenser.

[0079] Moreover, in the heating and sanitary hot water production mode:

[0080] When the system has the demand for heating and producing sanitary hot water, and the heating temperature and the water temperature for producing sanitary hot water do not reach the set conditions, the controller 1 only needs to open the electric valve on the heat recovery device side or the sanitary hot water side water pump 12-1 to recover the condensation heat through the heat recovery device 3 to obtain the required sanitary hot water, and operate the first heat exchanger side water pump 12-2 or the first heat exchanger side fan 13-1, and operate the second heat exchanger side water pump 12-3 or the second heat exchanger side fan 13-2 at the same time; in this way, the system can intelligently and smoothly complete the two functions of heating and producing sanitary hot water in the heating and sanitary hot water production mode;

[0081] When the system has heating and sanitary hot water production requirements, and the heating temperature does not reach the set requirements, while the water temperature for producing sanitary hot water reaches the set conditions, the controller 1 automatically closes the electric valve on the heat recovery device side or the sanitary hot water side water pump 12-1 to stop recovering the condensation heat, and runs the first heat exchanger side water pump 12-2 or the first heat exchanger side fan 13-1, and correspondingly, starts or increases the second heat exchanger side water pump 12-3 or the second heat exchanger side fan 13-2, so that the system's condensation heat exchange can be intelligently and smoothly switched between the heat recovery device 3 and the second heat exchanger 6, and the system can achieve the function of only heating in the heating and sanitary hot water production mode;

[0082] When the system has the demand for heating and producing sanitary hot water, and the heating temperature reaches the set requirements, but the water temperature for producing sanitary hot water does not reach the set conditions, the controller 1 continuously opens the electric valve on the heat recovery device side or the sanitary hot water side water pump 12-1, so that the required sanitary hot water can be obtained by recovering the condensation heat through the heat recovery device 3, and continuously runs the first heat exchanger side water pump 12-2 or the first heat exchanger side fan 13-1, and correspondingly, turns off the second heat exchanger side water pump 12-3 or the second heat exchanger side fan 13-2. In this way, the system can intelligently and smoothly realize the function of only producing sanitary hot water in the heating and sanitary hot water production mode;

[0083] Through the above-mentioned working method, in the same mode of heating and producing sanitary hot water, the system can intelligently and smoothly realize the flexible conversion among the three situations of heating and producing sanitary hot water, only heating, and only producing sanitary hot water under the same mode of heating and producing sanitary hot water. It abandons the practice of traditional technology that must forcibly change the system working mode to realize its conversion. It is precisely because the present invention does not need to switch the system working mode to realize the back and forth change of the two situations of producing sanitary hot water or stopping the production of sanitary hot water. In this way, the adaptability and intelligence of the heat recovery heat pump system and its device to load changes are improved.

[0084] Similarly, in the above working process, since the heat recovery device 3 is involved in the work or not, it will affect the amount of refrigerant circulation in the system, and the refrigerant operation is prone to imbalance. To solve this problem, the working mode of the refrigerant auxiliary flow path is as follows:

[0085] 1) When the system has a demand for producing sanitary hot water and the water temperature does not reach the set condition, the auxiliary four-way reversing valve 10 is electrically reversed, the D interface of the auxiliary four-way reversing valve 10 is connected to the E interface, and the C interface is connected to the S interface. During operation, part of the liquid refrigerant coming out of the second heat exchanger 6 passes through the third one-way valve 11-3, the D interface and the E interface of the auxiliary four-way reversing valve 10 and the outlet pipe of the liquid reservoir 9 in the reverse direction and enters the liquid reservoir 9, and then passes through the inlet pipe of the liquid reservoir, the C interface, the S interface and the second one-way valve 11-2 of the auxiliary four-way reversing valve 10, and finally merges with the refrigerant out of the outlet pipe of the throttling device 7 and flows to the first heat exchanger 5. Since the refrigerant flows through the liquid reservoir 9 in the reverse direction, only a small amount of refrigerant remains in the liquid reservoir by utilizing the structural characteristics of the small amount of liquid stored in the reverse flow of the liquid reservoir;

[0086] 2) When the system detects that the sanitary hot water temperature reaches the set condition or the system has no demand for producing sanitary hot water, the auxiliary four-way reversing valve 10 loses power and resets, the D interface of the auxiliary four-way reversing valve 10 is connected to the C interface, and the E interface is connected to the S interface. During operation, part of the liquid refrigerant from the second heat exchanger 6 enters the liquid reservoir in a positive direction through the third one-way valve 11-3, the D interface and the C interface of the auxiliary four-way reversing valve 10 and the inlet pipe of the liquid reservoir 9, and then passes through the outlet pipe of the liquid reservoir 9, the E interface and the S interface of the auxiliary four-way reversing valve 10, and the second one-way valve 11-2, and finally merges with the refrigerant from the throttling device 7 and enters the first heat exchanger 5. At this time, since the refrigerant flows through the liquid reservoir 9 in a positive direction, the liquid reservoir will store a large amount of refrigerant by utilizing the structural characteristics of the liquid reservoir with a large forward flow storage volume;

[0087] Through the above working method, the imbalance problem of the traditional heat recovery heat pump system that when the heat recovery device is put into heat recovery work, the heat recovery device accumulates more liquid refrigerant, resulting in a small amount of system refrigerant circulation, and when the heat recovery device is not put into heat recovery work, the system refrigerant circulation amount is too large is solved, the working performance of the system is improved, and the situation where the compressor is damaged by liquid shock is avoided. In this way, the working performance of the heat recovery system and its adaptability to load changes are improved, ensuring the stable and safe operation of the heat recovery heat pump system.

[0088] Embodiment 2

[0089] Figure 3 This is a schematic diagram of the implementation principle of the second embodiment. On the basis of the first embodiment, the throttling element 7 is replaced by a throttling element assembly; the throttling element assembly includes a refrigeration throttling element 7-1, a heating throttling element 7-2, a fifth one-way valve 11-5 and a sixth one-way valve 11-6; the refrigeration throttling element 7-1 and the fifth one-way valve 11-5 are connected in series to form a refrigeration throttling element assembly, the heating throttling element 7-2 and the sixth one-way valve 11-6 are connected in series to form a heating throttling element assembly, the refrigeration throttling element assembly and the heating throttling element assembly are connected in parallel to form the throttling element assembly, and the two ends of the throttling element assembly are connected to the connecting pipe between the first heat exchanger and the second heat exchanger. In the heat pump system of the present invention, when the refrigeration is working, the refrigerant will be throttled by the refrigeration throttling element assembly; when the heating is in operation, only sanitary hot water is produced, or the heating and sanitary hot water are produced, the refrigerant will be throttled by the heating throttling element assembly, and the rest of the working methods and working principles are the same as those of the first embodiment.

[0090] Embodiment 3

[0091] like Figure 4This is a schematic diagram of the implementation principle of the third embodiment. This embodiment is based on the second embodiment, and the connection method is changed as follows: the first check valve 11-1 and the third check valve 11-3 are cancelled, and the D interface of the auxiliary four-way reversing valve 10 is divided into two branches, and the two branches are respectively plugged into the connecting pipe between the cooling throttling device 7-1 and the fifth check valve 11-5, and the connecting pipe between the heating throttling device 7-2 and the sixth check valve 11-6. In this embodiment, the working method of the refrigerant auxiliary flow path is as follows:

[0092] If the user sets it to cooling mode or cooling and sanitary hot water mode, 1) when the system has cooling and sanitary hot water production needs, and the cooling temperature and the sanitary hot water temperature have not reached the set conditions, the auxiliary four-way reversing valve 10 is in an electrically switched state, the D interface of the auxiliary four-way reversing valve is connected to the E interface, and the C interface is connected to the S interface. During operation, after the liquid refrigerant coming out of the first heat exchanger 5 passes through the fifth one-way valve 11-5, part of the refrigerant will pass through the D interface, E interface, and the outlet pipe of the liquid reservoir 9 of the auxiliary four-way reversing valve 10, and enter the liquid reservoir in the reverse direction, and then flow out from the C interface, S interface, and fourth one-way valve 11-4 of the auxiliary four-way reversing valve and merge with the refrigerant coming out of the refrigeration throttling device to flow to the second heat exchanger 6; 2) when the system has cooling and sanitary hot water production needs, and the cooling temperature reaches the set conditions, but the water temperature for producing sanitary hot water does not reach the set conditions, the auxiliary four-way reversing valve 10 is electrically switched, the D interface of the auxiliary four-way reversing valve is connected to the E interface, and the C interface is connected to the S interface. The interface is connected to the S interface. During operation, part of the liquid refrigerant coming out of the second heat exchanger 6 passes through the sixth one-way valve 11-6, the D interface and the E interface of the auxiliary four-way reversing valve 10, and enters the liquid reservoir 9 from the outlet pipe of the liquid reservoir in the reverse direction, and then passes through the liquid reservoir inlet pipe, the C interface of the auxiliary four-way reversing valve 10, the S interface and the second one-way valve 11-2, and finally merges with the refrigerant out of the outlet pipe of the heating throttling element 7-2 and flows to the first heat exchanger 5; 3) When the temperature of the sanitary hot water reaches the set condition or When the system has no demand for producing sanitary hot water, the auxiliary four-way reversing valve 10 is in a power-off reset state. After the liquid refrigerant coming out of the first heat exchanger 5 passes through the fifth one-way valve 11-5, part of the refrigerant will pass through the D interface and C interface of the auxiliary four-way reversing valve 10 and the inlet pipe of the liquid reservoir 9 and enter the liquid reservoir in the forward direction. Then, it will flow out from the E interface and S interface of the auxiliary four-way reversing valve 10 and the fourth one-way valve 11-4 and merge with the refrigerant coming out of the refrigeration throttling device 7-1 to flow to the second heat exchanger 6.

[0093] If the user sets it to the sanitary hot water production mode, heating mode or heating and sanitary hot water production mode, the first heat exchanger 5 is used as an evaporator and the second heat exchanger 6 is used as a condenser. 1) When the system has a demand for producing sanitary hot water and the water temperature has not reached the set condition, the auxiliary four-way reversing valve 10 is in an energized reversing state. During operation, after the liquid refrigerant coming out of the second heat exchanger 6 passes through the sixth one-way valve 11-6, part of the refrigerant will pass through the D interface and E interface of the auxiliary four-way reversing valve 10 and the outlet pipe of the liquid reservoir 9, and then flow out from the inlet pipe of the liquid reservoir, the C interface and S interface of the auxiliary four-way reversing valve 10, and the second one-way valve 11-2, and then merge with the refrigerant coming out of the heating throttling device 7-2 and flow to the first heat exchanger 5; 2) When the temperature of sanitary hot water reaches the set condition or the system has no demand for producing sanitary hot water, the auxiliary four-way reversing valve 10 is in a power-off reset state. During operation, after the liquid refrigerant from the second heat exchanger 6 passes through the sixth one-way valve 11-6, part of the refrigerant will pass through the D interface and C interface of the auxiliary four-way reversing valve 10 and the inlet pipe of the liquid reservoir 9, and enter the liquid reservoir in a positive direction, and then flow out from the outlet pipe of the liquid reservoir, the E interface and S interface of the auxiliary four-way reversing valve, and the second one-way valve 11-2, and then merge with the refrigerant coming out of the heating throttling element 7-2 and flow to the first heat exchanger 5. The rest of the working method is the same as in the second embodiment.

[0094] Embodiment 4

[0095] Figure 5 The figure shows a schematic diagram of the implementation principle of the fourth embodiment. The heat pump system is a heat recovery heat pump system that adopts the principle of the present invention in a single cooling system or a single heating system, and is provided with a heat recovery device and a refrigerant auxiliary flow path. This embodiment is based on the first embodiment, and the main four-way reversing valve 4, the second one-way valve 11-2 and the third one-way valve 11-3 are not provided; and the connection mode is changed as follows: the outlet of the heat recovery device 3 is connected to the inlet of the first heat exchanger 5, the outlet of the second heat exchanger 6 is connected to the inlet of the gas-liquid separator 8, the outlet of the first one-way valve 11-1 is directly connected to the D interface of the auxiliary four-way reversing valve 10, and the S pipe of the auxiliary four-way reversing valve 10 is directly connected to the inlet of the fourth one-way valve 11-4. In the heat pump system of this embodiment, the first heat exchanger 5 is always used as a condenser, and the second heat exchanger 6 is used as an evaporator. The specific working method is as follows:

[0096] When the system is working, the high-temperature and high-pressure gaseous refrigerant discharged by the compressor 2 first enters the heat recovery device 3, and then enters the first heat exchanger 5. The gaseous refrigerant releases the condensation heat in the heat recovery device 3 and the first heat exchanger 5 and is converted into a liquid refrigerant. Then, the liquid refrigerant passes through the throttling device 7 and enters the second heat exchanger 6. The refrigerant absorbs the heat of the external medium in the second heat exchanger 6 and is converted into a low-temperature and low-pressure gaseous refrigerant, and then returns to the compressor 2 through the gas-liquid separator 8.

[0097] During this process, when the system has a demand for producing sanitary hot water and the water temperature has not reached the set conditions, the controller 1 automatically opens the electric valve on the side of the heat recovery device 3 or opens the sanitary hot water side water pump 12-1, so that the required sanitary hot water can be obtained by recovering the condensation heat through the heat recovery device 3, and accordingly, the first heat exchanger side water pump 12-2 or the first heat exchanger side fan 13-1 is automatically closed or adjusted down; when the sanitary hot water temperature has reached the set conditions or the system has no demand for producing sanitary hot water, the controller 1 automatically closes the electric valve on the side of the heat recovery device 3 or the sanitary hot water side water pump 12-1, and the heat recovery device 3 can stop recovering the condensation heat, and accordingly, the first heat exchanger side water pump 12-2 or the first heat exchanger side fan 13-1 is automatically opened or adjusted up. In this way, the flexible conversion of the system's condensing heat exchange between the heat recovery device 3 and the first heat exchanger 5 can be completed intelligently and smoothly, abandoning the traditional technology that must forcibly change the system working mode to achieve its conversion. It is precisely because there is no need to change the system's working mode to achieve the two situations of producing sanitary hot water or stopping the production of sanitary hot water. In this way, the adaptability and intelligence of the heat recovery heat pump system to load changes are improved.

[0098] Similarly, in the above working process, whether the heat recovery device participates in the heat recovery work will affect the amount of refrigerant circulating in the system, which may easily lead to the phenomenon of unbalanced refrigerant operation. At this time, the working mode of the refrigerant auxiliary flow path is as follows:

[0099] 1) When the system has a demand for producing sanitary hot water and the water temperature has not reached the set condition, the auxiliary four-way reversing valve 10 is electrically reversed, and the D interface of the auxiliary four-way reversing valve 10 is connected to the E interface, and the C interface is connected to the S interface; during operation, part of the liquid refrigerant coming out of the first heat exchanger 5 enters the liquid reservoir in the reverse direction through the first one-way valve 11-1, the D interface and the E interface of the auxiliary four-way reversing valve 10 and the outlet pipe of the liquid reservoir 9, and then passes through the inlet pipe of the liquid reservoir 9, the C interface and the S interface of the auxiliary four-way reversing valve 10 and the fourth one-way valve 11-4, and finally merges with the refrigerant out of the outlet pipe of the throttling device 7 and flows to the second heat exchanger 6. At this time, since the refrigerant flows through the liquid reservoir 9 in the reverse direction, only a small amount of refrigerant remains in the liquid reservoir by utilizing the structural characteristics of the liquid reservoir with a small amount of reverse flow liquid storage.

[0100] 2) When the system detects that the sanitary hot water temperature has reached the set condition or the system has no demand for producing sanitary hot water, the auxiliary four-way reversing valve 10 loses power and resets, and the D interface of the auxiliary four-way reversing valve 10 is connected to the C interface, and the E interface is connected to the S interface; during operation, part of the liquid refrigerant coming out of the first heat exchanger 5 passes through the first one-way valve 11-1, the D interface and the C interface of the auxiliary four-way reversing valve 10 and the inlet pipe of the liquid reservoir 9, and enters the liquid reservoir in a positive direction, and then passes through the outlet pipe of the liquid reservoir 9, the E interface and the S interface of the auxiliary four-way reversing valve 10 and the fourth one-way valve 11-4, and finally merges with the refrigerant coming out of the throttling device 7 and enters the second heat exchanger 6. At this time, since the refrigerant flows through the liquid reservoir 9 in a positive direction, the liquid reservoir will store a large amount of refrigerant by utilizing the structural characteristics of the liquid reservoir with a large forward flow storage capacity.

[0101] Through the above working method, the imbalance problem of the traditional heat recovery heat pump system is solved, that is, when the heat recovery device is put into use, the heat recovery device accumulates more liquid refrigerant, resulting in a small amount of system refrigerant circulation, and when the heat recovery device is not put into use, the system refrigerant circulation amount is too large, thereby avoiding the situation where the compressor is damaged by liquid shock. In this way, the adaptability of the heat recovery system to load changes is improved, ensuring the stable and safe operation of the heat recovery heat pump system.

[0102] Embodiment 5

[0103] like Figure 6 In this embodiment, a gas-liquid separator heating pipe 14 is added to the heat pump system of the first embodiment. The gas-liquid separator heating pipe 14 is installed inside the gas-liquid separator 8 or coiled on the outside of the shell of the gas-liquid separator 8 (the figure shows that the gas-liquid separator heating pipe 14 is coiled on the outside of the shell of the gas-liquid separator 8). Through the pipeline connector, the inlet pipe of the gas-liquid separator heating pipe 14 is plugged into the connecting pipe between the compressor 2 and the heat recovery device 3, and the outlet pipe of the gas-liquid separator heating pipe 14 is plugged into the outlet pipe of the heat recovery device 3.

[0104] During the operation, some high-temperature gaseous refrigerant in the exhaust pipe of the compressor 2 also enters the gas-liquid separator heating tube 14, heats the refrigerant in the gas-liquid separator 8 and then merges with the refrigerant in the outlet pipe of the heat recovery device 3; the function of the gas-liquid separator heating tube 14 is to heat the refrigerant in the gas-liquid separator 8 so that the refrigerant at the outlet of the gas-liquid separator 8 is always in a gaseous state, eliminating the adverse effects on the compressor caused by the imbalance of the refrigerant in the above-mentioned working process, ensuring that no liquid refrigerant returns to the compressor in the system, and improving the reliability and safety of the working process of the heat recovery heat pump system.

[0105] The working conditions of other parts of the system are the same as those in the first embodiment without the gas-liquid separator heating tube 14, and will not be described in detail here. Of course, the use of the gas-liquid separator heating tube can be applied not only to the first embodiment, but also to the second, third and fourth embodiments, and the working mode of the refrigerant auxiliary flow path is also the same.

[0106] Embodiment 6

[0107] like Figure 7 This is an embodiment of using the gas-liquid separator heating tube 14 in a situation where there is no auxiliary refrigerant flow path. At this time, the working mode of the heat pump system is as follows:

[0108] If the system is set to refrigeration or refrigeration and sanitary hot water production mode, the main four-way reversing valve 4 is in a power-off reset state, and the high-temperature and high-pressure gaseous refrigerant discharged from the compressor 2 first enters the heat recovery device 3, and then enters the first heat exchanger 5 through the D interface and C interface of the main four-way reversing valve 4. The gaseous refrigerant releases the condensation heat in the heat recovery device 3 and the first heat exchanger 5 and is converted into a liquid refrigerant. The liquid refrigerant then flows through the throttling device 7 and enters the second heat exchanger 6. The refrigerant absorbs the heat of the external medium in the second heat exchanger 6 and evaporates into a low-temperature and low-pressure gaseous refrigerant, and then passes through the E interface and S interface of the main four-way reversing valve 4 and returns to the compressor 2 through the gas-liquid separator 8.

[0109] If the system is set to heating, producing sanitary hot water or heating and producing sanitary hot water mode, when working, the main four-way reversing valve 4 is in the energized reversing state, and the high-temperature and high-pressure gaseous refrigerant discharged by the compressor 2 first enters the heat recovery device 3, and then enters the second heat exchanger 6 through the D interface and E interface of the main four-way reversing valve 4. The gaseous refrigerant releases heat in the heat recovery device 3 and the second heat exchanger 6 and is converted into liquid refrigerant. Then the liquid refrigerant flows through the throttling device 7 and enters the first heat exchanger 5. The refrigerant absorbs heat from the external medium in the first heat exchanger 5 and is converted into a low-temperature and low-pressure gaseous refrigerant, and then passes through the C interface and S interface of the main four-way reversing valve 4 and returns to the compressor 2 through the gas-liquid separator 8.

[0110] During the above working process, some high-temperature gaseous refrigerant in the exhaust pipe of the compressor 2 also enters the gas-liquid separator heating tube 14, heats the refrigerant in the gas-liquid separator 8 and then merges with the refrigerant in the outlet pipe of the heat recovery device 3; the function of the gas-liquid separator heating tube 14 is to heat the refrigerant in the gas-liquid separator 8 so that it is always in a gaseous state, eliminating the adverse effects on the compressor caused by the imbalance of refrigerant in the above working process, ensuring that no liquid refrigerant returns to the compressor in the system, and improving the reliability and safety of the working process of the heat recovery heat pump system.

[0111] The above embodiments are only preferred implementation modes listed for the convenience of explaining and illustrating the technical solutions and working principles of the present invention. In fact, there are many forms and combinations of implementation modes of the present invention, which are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations and simplifications made without departing from the spirit and principles of the present invention shall be equivalent replacement modes and shall be included in the protection scope of the present invention.

Claims

1. A heat pump system capable of flexibly converting heat recovery, characterized in that: include: A compressor (2), a heat recovery device (3), a main four-way reversing valve (4), a first heat exchanger (5), a second heat exchanger (6), a throttling device (7), and a gas-liquid separator (8); the main four-way reversing valve (4) is provided with four interfaces D, C, S, and E, which are connected by pipelines to connect the compressor exhaust port to the heat recovery device inlet, the heat recovery device outlet to the D interface of the main four-way reversing valve, the main four-way reversing valve C interface to the first heat exchanger inlet, the first heat exchanger outlet to the throttling device inlet, the throttling device outlet to the second heat exchanger inlet, the second heat exchanger outlet to the E interface of the main four-way reversing valve, and the main four-way reversing valve S interface to the first heat exchanger inlet. The interface is connected to the inlet of the gas-liquid separator, and the outlet of the gas-liquid separator is connected to the suction port of the compressor; the heat pump system also includes a refrigerant auxiliary flow path, and the refrigerant auxiliary flow path includes a liquid reservoir (9), an auxiliary four-way reversing valve (10) and four one-way valves; the auxiliary four-way reversing valve (10) has four interfaces D, C, S, and E; through a pipeline connector, the connecting pipe of the D interface of the auxiliary four-way reversing valve (10) is plugged into the connecting pipe between the first heat exchanger (5) and the throttling element (7), the C interface of the auxiliary four-way reversing valve (10) is connected to the inlet of the liquid reservoir (9), the E interface of the auxiliary four-way reversing valve (10) is connected to the outlet of the liquid reservoir, and the S interface of the auxiliary four-way reversing valve (10) is connected to the outlet of the liquid reservoir. The connecting pipe of the interface is plugged into the connecting pipe between the first heat exchanger (5) and the throttling element (7); the four one-way valves are respectively referred to as the first one-way valve (11-1), the second one-way valve (11-2), the third one-way valve (11-3), and the fourth one-way valve (11-4); the first one-way valve (11-1) is installed on the D interface connecting pipe of the auxiliary four-way reversing valve (10), and the outlet end of the first one-way valve is connected to the D interface of the auxiliary four-way reversing valve; the second one-way valve (11-2) is installed on the connecting pipe of the S interface of the auxiliary four-way reversing valve (10), and the inlet end of the second one-way valve is connected to the S interface of the auxiliary four-way reversing valve; the inlet pipe of the third one-way valve (11-3) is plugged into the connecting pipe between the throttling element (7) and the second heat exchanger (6), and the outlet pipe is plugged into the D interface of the auxiliary four-way reversing valve (10). The inlet pipe of the fourth check valve (11-4) is plugged into the connecting pipe between the S interface of the auxiliary four-way reversing valve (10) and the second check valve (11-2), and the outlet pipe is plugged into the connecting pipe between the second heat exchanger (6) and the throttling element (7).

2. According to claim 1, a heat pump system capable of flexibly converting heat recovery is characterized in that: The heat recovery device (3) is a heat exchanger for heat exchange between refrigerant and water, and its peripheral water channel side also includes an electric valve or a sanitary hot water side water pump (12-1); the first heat exchanger (5) and the second heat exchanger (6) are heat exchangers for heat exchange between refrigerant and water or heat exchangers for heat exchange between refrigerant and air. When the first heat exchanger and the second heat exchanger are heat exchangers for heat exchange between refrigerant and water, their peripheral water channel sides also include a first heat exchanger side water pump (12-2) and a second heat exchanger side water pump (12-3) respectively; when the first heat exchanger and the second heat exchanger are heat exchangers for heat exchange between refrigerant and air, their air sides also include a first heat exchanger side fan (13-1) and a second heat exchanger side fan (13-2) respectively.

3. A heat pump system capable of flexibly converting heat recovery according to any one of claims 1 or 2, characterized in that: The throttling device (7) is a throttling device assembly; the throttling device assembly comprises a refrigeration throttling device (7-1), a heating throttling device (7-2), a fifth one-way valve (11-5), and a sixth one-way valve (11-6); the refrigeration throttling device (7-1) and the fifth one-way valve (11-5) are connected in series to form a refrigeration throttling device assembly, the heating throttling device (7-2) and the sixth one-way valve (11-6) are connected in series to form a heating throttling device assembly, the refrigeration throttling device assembly and the heating throttling device assembly are connected in parallel to form the throttling device assembly, and both ends of the throttling device assembly are connected to the connecting pipe between the first heat exchanger (5) and the second heat exchanger (6).

4. A heat pump system capable of flexibly converting heat recovery according to claim 3, characterized in that: The heat pump system does not include a first check valve (11-1) and a third check valve (11-3), but instead divides the D-interface pipe of the auxiliary four-way reversing valve (10) into two branch pipes, and the two branch pipes are respectively plugged into the connecting pipe between the cooling throttling element (7-1) and the fifth check valve (11-5), and the connecting pipe between the heating throttling element (7-2) and the sixth check valve (11-6).

5. The heat pump system capable of flexibly converting heat recovery according to claim 1, characterized in that: In the heat pump system, the main four-way reversing valve (4), the second one-way valve (11-2), and the third one-way valve (11-3) are eliminated; the outlet of the heat recovery device (3) is connected to the inlet of the first heat exchanger (5), the outlet of the second heat exchanger (6) is connected to the inlet of the gas-liquid separator (8), the outlet of the first one-way valve (11-1) is directly connected to the D interface of the auxiliary four-way reversing valve (10), and the S interface of the auxiliary four-way reversing valve (10) is directly connected to the inlet of the fourth one-way valve (11-4).

6. A heat pump system capable of flexibly converting heat recovery according to claim 2, characterized in that: In the heat pump system, the main four-way reversing valve (4), the second one-way valve (11-2), and the third one-way valve (11-3) are eliminated; the outlet of the heat recovery device (3) is connected to the inlet of the first heat exchanger (5), the outlet of the second heat exchanger (6) is connected to the inlet of the gas-liquid separator (8), the outlet of the first one-way valve (11-1) is directly connected to the D interface of the auxiliary four-way reversing valve (10), and the S interface of the auxiliary four-way reversing valve (10) is directly connected to the inlet of the fourth one-way valve (11-4).

7. A heat pump system capable of flexibly converting heat recovery according to any one of claims 1, 2, 4, 5, and 6, characterized in that: The heat pump system further comprises a gas-liquid separator heating pipe (14), which is installed inside the gas-liquid separator (8) or coiled around the outside of the shell of the gas-liquid separator (8). The inlet pipe of the gas-liquid separator heating pipe (14) is plugged into the connecting pipe between the compressor (2) and the heat recovery device (3) through a pipe connector, and the outlet pipe of the gas-liquid separator heating pipe (14) is plugged into the outlet pipe of the heat recovery device (3).

8. The heat pump system capable of flexibly converting heat recovery according to claim 3, characterized in that: The heat pump system further comprises a gas-liquid separator heating pipe (14), which is installed inside the gas-liquid separator (8) or coiled around the outside of the shell of the gas-liquid separator (8). The inlet pipe of the gas-liquid separator heating pipe (14) is plugged into the connecting pipe between the compressor (2) and the heat recovery device (3) through a pipe connector, and the outlet pipe of the gas-liquid separator heating pipe (14) is plugged into the outlet pipe of the heat recovery device (3).

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