A heat pump dryer with multi-stage waste heat recovery

Abstract

The present application relates to the technical field of dryers, and in particular to a heat pump dryer with multi-stage waste heat recovery, which includes a frame, a heat absorption chamber and a heat release chamber are arranged in the frame, a primary evaporator, a secondary evaporator, a tertiary evaporator and a quaternary evaporator are arranged in the heat absorption chamber from bottom to top, a mounting plate is arranged in the frame, a heat recovery centrifugal fan is arranged on the mounting plate, a heat recovery pipe is arranged at the air inlet end of the heat recovery centrifugal fan, and the air outlet end of the heat recovery centrifugal fan is connected to the heat absorption chamber, an exhaust port is opened on the side wall of the frame, and the exhaust port is connected to the primary evaporator, and a primary heat release module, a secondary heat release module, a tertiary heat release module and a quaternary heat release module are arranged in the frame corresponding to the primary evaporator, the secondary evaporator, the tertiary evaporator and the quaternary evaporator, respectively. The present application has the effect of improving the heat recovery rate.

Description

Technical Field

[0001] The present application relates to the technical field of dryers, and in particular to a heat pump dryer with multi-stage waste heat recovery. Background Art

[0002] A heat pump system is a device that absorbs heat from the external environment through a low-temperature heat source (such as air, water or soil) and transfers it to the space that needs to be heated. A heat pump dryer is a drying equipment that uses heat pump technology. It uses the heat pump principle to absorb heat from the air and transfer it to the material to be dried, thereby achieving a low-temperature and efficient drying process.

[0003] The utility model patent with the announcement number CN202881720U discloses a high-efficiency heat pump type dryer, including a machine body, in which a rotating barrel for accommodating clothes is provided; an air channel, including an air inlet and an air outlet, the air channel is connected to the rotating barrel; a heat pump system, the heat pump system includes a compressor, a radiator, an expansion valve and a heat dissipator, the refrigerant R134a is pressurized by the compressor to become a high-temperature and high-pressure gas, and after entering the radiator, it enters the heat dissipator through the expansion valve and recirculates back to the compressor, the radiator is arranged in the air channel, and is used to perform heat exchange on the air flowing through the air channel; a dehumidification device, which is used to dehumidify the air in the air channel. It also includes a heat recovery device, which is arranged at the air inlet, and the air at the air inlet enters the air channel through the heat recovery device, and the air discharged from the rotating barrel is discharged from the air outlet through the heat recovery device.

[0004] In the above-mentioned patent disclosure, although two heat recovery devices are provided for heat recovery, there is a lack of connection between the two heat recovery devices, and there is still a problem of partial heat dissipation, resulting in low heat recovery efficiency. Summary of the invention

[0005] In order to improve the heat recovery rate, the present application provides a heat pump dryer with multi-stage waste heat recovery.

[0006] The present application provides a heat pump dryer with multi-stage waste heat recovery, which adopts the following technical solution:

[0007] A heat pump dryer with multi-stage waste heat recovery comprises a frame, wherein a heat absorption chamber and a heat release chamber are arranged in the frame, and a first-stage evaporator, a second-stage evaporator, a third-stage evaporator and a fourth-stage evaporator are arranged in the heat absorption chamber in sequence from bottom to top, a mounting plate is arranged in the frame, a heat recovery centrifugal fan is arranged on the mounting plate, an air outlet end of the heat recovery centrifugal fan is connected to the heat absorption chamber, an exhaust port is arranged on the side wall of the frame, and the exhaust port is connected to the first-stage evaporator, and a first-stage heat release module, a second-stage heat release module, a third-stage heat release module and a fourth-stage heat release module are arranged in the frame corresponding to the first-stage evaporator, the second-stage evaporator, the third-stage evaporator and the fourth-stage evaporator, respectively, and the first-stage heat release module, the second-stage heat release module, the third-stage heat release module and the fourth-stage heat release module are all connected to the heat release chamber;

[0008] It also includes a drying machine body, the drying machine body is respectively provided with an air inlet and an air return port, an air inlet pipe is connected between the frame and the air inlet, and a heat recovery pipe is connected between the air inlet end of the heat recovery centrifugal fan and the air return port;

[0009] A filter is arranged inside the heat recovery pipe, a collecting box is detachably arranged on the bottom surface of the heat recovery pipe, the collecting box is located on the windward side of the filter, and a cleaning mechanism for scraping impurities is arranged on the heat recovery pipe.

[0010] By adopting the above technical solution, the first-stage heat release module, the second-stage heat release module, the third-stage heat release module, and the fourth-stage heat release module heat the air step by step together, and transmit the heat to the terminal device. After the terminal device has finished using the heat, the waste heat gas is discharged. At this time, the heat recovery centrifugal fan is started, and the waste heat gas enters the heat absorption chamber through the heat recovery centrifugal fan, and passes through the first-stage evaporator, the second-stage evaporator, the third-stage evaporator and the fourth-stage evaporator in sequence. The waste heat gas is continuously transferred through the continuous evaporators, and the gas after heat exchange and cooling is finally discharged from the exhaust port. This process ensures that the heat of the waste heat gas is completely recovered to the evaporator, thereby improving the heat recovery rate;

[0011] The drying machine body is used to dry textile products such as clothes. The air is heated by the heat release cavity in the frame body. The heated gas passes through the air inlet pipe and the air inlet in turn, and then enters the drying machine body. Under the action of the hot air, the textile products such as clothes are dried. The residual heat gas after drying flows back to the heat absorption cavity of the frame body through the return air port. This is repeated, which is beneficial to improve the stability of the drying machine body in drying textile products such as clothes.

[0012] The filter is used to filter impurities such as cloth scraps mixed in the waste heat gas. When the waste heat gas flows along the heat recovery pipe, the filter filters the waste heat gas. At this time, impurities such as cloth scraps are retained on the windward side of the filter and are collected in the collection box under the action of the cleaning mechanism, which is beneficial to reduce the entry of impurities such as cloth scraps into the heat absorption chamber, thereby affecting the normal use of evaporators at all levels.

[0013] Optionally, a subcooler is provided between the first-stage evaporator and the second-stage evaporator, and the subcooler is respectively connected and arranged between the third-stage evaporator and the third-stage heat release module, and between the fourth-stage evaporator and the fourth-stage heat release module.

[0014] By adopting the above technical scheme, the subcooler is used to reduce the temperature of the refrigerant, and the three-stage heat release module and the four-stage heat release module are used to further increase the heat of the inhaled air. Therefore, the refrigerant temperature in the three-stage heat release module and the four-stage heat release module is high. The temperature of the refrigerant is reduced by the subcooler, and the heat transfer efficiency of the three-stage evaporator and the four-stage evaporator to the waste heat gas just entering the heat absorption chamber is improved. The refrigerant that has re-transferred heat helps the three-stage heat release module and the four-stage heat release module to shorten the compression heating time and improve the efficiency of heating the heat of the inhaled air.

[0015] Optionally, the first-stage heat release module, the second-stage heat release module, the third-stage heat release module, and the fourth-stage heat release module respectively include a condenser, a compressor, a gas-liquid separator, and an expansion valve, and the compressor, the condenser, the expansion valve, evaporators of each stage, and the gas-liquid separator are connected in sequence through pipelines.

[0016] By adopting the above technical solution, the compressor compresses and heats the refrigerant gas and then transports it to the condenser. The working process of the condenser is a heat release process, so the released heat is transferred to the air, thereby heating the air. The refrigerant gas changes from gas to liquid after releasing heat, and then flows into the evaporator after passing through the expansion valve. The evaporator is an important part of refrigeration. By absorbing the heat of the waste heat gas, the liquid refrigerant is converted back into gaseous refrigerant, and then input into the gas-liquid separator, and finally into the compressor. This process is repeated to achieve heating of the air and heat recovery of the waste heat gas, which is beneficial to improving the stability of air heating and heat recovery of waste heat air.

[0017] Optionally, the cleaning mechanism includes a scraper, the middle part of the filter is rotatably connected to a rotating shaft, the scraper is arranged at one end of the rotating shaft, the scraper is attached to the windward surface of the filter, and a fan body is arranged at the other end of the rotating shaft. The windward surface of the filter is provided with a material guide groove, and the material guide groove is inclined toward the direction of the collecting box. The filter is provided with a pushing component for scraping off viscous impurities in the material guide groove.

[0018] By adopting the above technical solution, when the waste heat gas flows through the heat recovery pipe, the waste heat gas drives the fan body to rotate, and the fan body drives the scraper to rotate through the rotating shaft. At this time, the scraper scrapes the windward surface of the filter, and scrapes the impurities such as cloth scraps adhering to the windward surface into the material guide trough, and under the action of the self-gravity of the impurities such as cloth scraps, they are finally collected in the collection box, which is beneficial to improve the stability of the collection of impurities such as cloth scraps.

[0019] Optionally, the pushing assembly includes a pushing block, which is slidably arranged in the material guide groove, and a connecting rod is arranged on one side of the pushing block, and the connecting rod extends outside the filter screen. The connecting rod is slidably connected to the filter screen, and a pull rod is arranged at one end of the connecting rod, and the bottom end of the pull rod extends outside the heat recovery pipe, and the heat recovery pipe is provided with an elastic member for cooperating with the pulling of the pull rod.

[0020] By adopting the above technical solution, when the pull rod is pulled downward, the pull rod drives the push block to descend through the connecting rod. At this time, the push block slides along the inner wall of the material guide trough, and the push block pushes down the impurities adhering to the material guide trough, and finally collects them in the collection box, which is beneficial to reduce the accumulation of impurities in the material guide trough and improve the stability of impurity collection.

[0021] Optionally, the elastic member is a first spring, which is arranged on one side of the pull rod, one end of the first spring is fixedly connected to the side wall of the pull rod, and the other end of the first spring is fixedly connected to the inner bottom wall of the heat recovery pipe.

[0022] By adopting the above technical solution, when the pull rod is pulled downward, the pull rod squeezes the first spring downward, and the first spring stores elastic force. When the pull rod is released, the first spring releases the elastic force and drives the pull rod to move upward. The pull rod drives the push block to move upward through the connecting rod, and the push block is then reset and impacts the filter. The dust on the filter is shaken off by the impact vibration force, and the impurities on the filter are shaken off by the scraper, thereby improving the stability of impurity collection.

[0023] Optionally, the connecting rod includes a cylinder, a rod and a second spring, the rod is slidably connected to the cylinder, the second spring is arranged in the cylinder, one end of the second spring is fixedly connected to the inner wall of the cylinder, and the other end of the second spring is fixedly connected to one end of the rod.

[0024] By adopting the above technical solution, when the push block moves along the material guide trough, since the material guide trough is set at an angle, the rod is stretched when the push block moves downward, and the rod stretches the second spring. When the push block rises, the second spring releases the elastic force, retracts the rod and moves it into the cylinder, ensuring that the push block is always close to the material guide trough, thereby improving the stability of the push block in pushing down impurities in the material guide trough.

[0025] In summary, this application includes the following beneficial technical effects:

[0026] The first-stage heat release module, the second-stage heat release module, the third-stage heat release module, and the fourth-stage heat release module heat the air step by step together and transfer the heat to the terminal equipment. After the terminal equipment has finished using the heat, it discharges the waste heat gas. At this time, the heat recovery centrifugal fan is started, and the waste heat gas enters the heat absorption chamber through the heat recovery pipe, and passes through the first-stage evaporator, the second-stage evaporator, the third-stage evaporator and the fourth-stage evaporator in sequence. The waste heat gas is continuously transferred through the continuous evaporators, and the gas after heat exchange and cooling is finally discharged from the exhaust port. This process ensures that the heat of the waste heat gas is completely recovered to the evaporator, thereby improving the heat recovery rate;

[0027] The filter is used to filter impurities such as cloth scraps mixed in the waste heat gas. When the waste heat gas flows along the heat recovery pipe, the filter filters the waste heat gas. At this time, impurities such as cloth scraps are retained on the windward side of the filter and are collected in the collection box under the action of the cleaning mechanism, which is beneficial to reduce the entry of impurities such as cloth scraps into the heat absorption chamber, thereby affecting the normal use of evaporators at all levels. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a first overall structural schematic diagram of a heat pump dryer with multi-stage waste heat recovery in the present application;

[0029] Figure 2 It is a second overall structural schematic diagram of the heat pump dryer with multi-stage waste heat recovery of the present application;

[0030] Figure 3 It is a schematic diagram of the overall structure of the frame of the present application;

[0031] Figure 4 It is a schematic diagram of the connection between the primary heat release module and the primary evaporator of the present application;

[0032] Figure 5 It is a schematic diagram of the connection between the three-stage heat release module and the four-stage heat release module of the present application and the three-stage evaporator and the four-stage evaporator respectively;

[0033] Figure 6 is a partial cross-sectional view of the heat recovery pipe of the present application;

[0034] Figure 7 It is a structural schematic diagram of the pusher assembly of the present application;

[0035] Figure 8 It is a cross-sectional view of the connecting rod of the present application.

[0036] Description of reference numerals: 1, frame; 2, heat absorption chamber; 3, heat release chamber; 4, air inlet; 5, exhaust port; 6, primary evaporator; 7, secondary evaporator; 8, tertiary evaporator; 9, quaternary evaporator; 10, mounting plate; 11, heat recovery centrifugal fan; 12, heat recovery pipe; 13, primary heat release module; 14, secondary heat release module; 15, tertiary heat release module; 16, quaternary heat release module; 17, subcooler; 18 , condenser; 19, compressor; 20, gas-liquid separator; 21, expansion valve; 22, drying body; 23, filter; 24, collecting box; 25, scraper; 26, rotating shaft; 27, fan body; 28, material guide trough; 29, pushing block; 30, connecting rod; 31, pull rod; 32, first spring; 33, cylinder; 34, rod; 35, second spring; 36, air inlet; 37, return air outlet; 38, air inlet pipe. DETAILED DESCRIPTION

[0037] The following is combined with Figure 1-8 This application is described in further detail.

[0038] See also Figure 1-Figure 3 A heat pump dryer with multi-stage waste heat recovery includes a frame 1, and a heat absorption chamber 2 and a heat release chamber 3 are provided in the frame 1. The heat release chamber 3 is provided with an air inlet 4, and the air inlet 4 is located on one side of the frame 1. The heat absorption chamber 2 is provided with an exhaust port 5, and the exhaust port 5 is located on the other side of the frame 1. A primary evaporator 6, a secondary evaporator 7, a tertiary evaporator 8 and a quaternary evaporator 9 are fixedly connected and installed in the heat absorption chamber 2 from bottom to top, and the exhaust port 5 is connected to the primary evaporator 6 at the bottom. A mounting plate 10 is fixedly installed in the frame 1, and a heat recovery centrifugal fan 11 is fixedly installed on the top surface of the mounting plate 10. The heat recovery centrifugal fan 11 includes an air inlet end and an air outlet end. The air inlet end of the heat recovery centrifugal fan 11 is fixedly connected with a heat recovery pipe 12, and the heat recovery pipe 12 extends outside the frame 1. The air outlet end of the heat recovery centrifugal fan 11 is fixedly connected to the heat absorption chamber 2 , and the air outlet end of the heat recovery centrifugal fan 11 is located above the four-stage evaporator 9 .

[0039] The layer corresponding to the primary evaporator 6 in the frame 1 is connected and installed with a primary heat release module 13, the layer corresponding to the secondary evaporator 7 is connected and installed with a secondary heat release module 14, the layer corresponding to the third-stage evaporator 8 is connected and installed with a third-stage heat release module 15, and the layer corresponding to the fourth-stage evaporator 9 is connected and installed with a fourth-stage heat release module 16. The primary heat release module 13, the secondary heat release module 14, the third-stage heat release module 15, and the fourth-stage heat release module 16 are all connected to the heat release chamber 3.

[0040] Air is sucked into the heat release chamber 3 through the air inlet 4, and the first-stage heat release module 13, the second-stage heat release module 14, the third-stage heat release module 15 and the fourth-stage heat release module 16 release heat in the heat release chamber 3 step by step, thereby heating the air in the heat release chamber 3 to the required temperature, and then supplying the heated air to the terminal device for use. In this embodiment, the terminal device is a heat pump dryer. After the terminal device has finished using the heat, the residual heat is sucked into the heat release chamber 3 through the heat recovery pipe 12. After passing through the first-stage evaporator 6, the second-stage evaporator 7, the third-stage evaporator 8 and the fourth-stage evaporator 9 in sequence, the residual heat air completely transfers the heat to the refrigerant in the evaporator, and is finally discharged from the exhaust port 5.

[0041] See also Figure 3 and Figure 5 A subcooler 17 is also fixedly installed in the heat absorption chamber 2, and the subcooler 17 is located between the primary evaporator 6 and the secondary evaporator 7. The subcooler 17 is also connected between the third-stage evaporator 8 and the third-stage heat release module 15, and between the fourth-stage evaporator 9 and the fourth-stage heat release module 16.

[0042] The subcooler 17 is used to reduce the temperature of the refrigerant. Since the heat release temperature of the three-stage heat release module 15 and the four-stage heat release module 16 is high, the temperature of the refrigerant used for heat transfer is high. Since the three-stage evaporator 8 and the four-stage evaporator 9 are first in contact with the high-temperature waste heat, after the temperature of the refrigerant is reduced by the subcooler 17, the high-temperature waste heat transfers the heat to the low-temperature refrigerant, thereby improving the recovery rate of the waste heat. In addition, obtaining a high-temperature refrigerant also helps the three-stage heat release module 15 and the four-stage heat release module 16 to shorten the compression heating time and improve the efficiency of the intake air addition.

[0043] See also Figure 3 and Figure 4 The first-stage heat release module 13, the second-stage heat release module 14, the third-stage heat release module 15 and the fourth-stage heat release module 16 respectively include a condenser 18, a compressor 19, a gas-liquid separator 20 and an expansion valve 21. The compressor 19, the condenser 18, the expansion valve 21, the evaporators of each stage and the gas-liquid separator 20 are sequentially connected through pipelines.

[0044] The first-stage heat release module 13 and the second-stage heat release module 14 are placed on the same layer in the frame 1 , and the third-stage heat release module 15 and the fourth-stage heat release module 16 are placed on the same layer in the frame 1 .

[0045] The connection sequence of the primary heat release module 13 and the secondary heat release module 14 is respectively: compressor 19, condenser 18, expansion valve 21, primary evaporator 6 / secondary evaporator 7, gas-liquid separator 20, compressor 19.

[0046] The connection sequence of the third-stage heat release module 15 and the fourth-stage heat release module 16 is respectively: compressor 19, condenser 18, expansion valve 21, subcooler 17, third-stage evaporator 8 / fourth-stage evaporator 9, gas-liquid separator 20, compressor 19.

[0047] The compressor 19 compresses and heats the refrigerant gas and delivers the refrigerant gas to the condenser 18. The working process of the condenser 18 is a heat release process, so the condenser 18 heats the inhaled air through the high-temperature refrigerant. After releasing heat, the refrigerant gas changes from gas to liquid, and then passes through the expansion valve 21 and is input into the evaporator. The evaporator is an important part of refrigeration. By absorbing the heat of the waste heat gas, the liquid refrigerant is converted back into gas, and then input into the gas-liquid separator 20. The gas-liquid separator 20 ensures that only gaseous refrigerant enters the compressor 19. This is repeated to achieve heating of the air and heat recovery of the waste heat gas.

[0048] It is worth mentioning that the model of the refrigerant in this embodiment is specifically R245FA, pentafluoropropane, which is a colorless, transparent, easy-flowing liquid with a critical temperature of 154°C.

[0049] On the other hand, see Figure 2 A heat pump dryer with multi-stage waste heat recovery also includes a drying machine body 22, which is arranged opposite to the frame 1. The drying machine body 22 is respectively provided with an air inlet 36 and an air return port 37. The heat release chamber 3 of the frame 1 is fixedly connected to the air inlet 36 via an air inlet pipe 38, and the end of the heat return pipe 12 away from the frame 1 is fixedly connected to the air return port 37.

[0050] The heat recovery pipe 12 is used to dry textile products such as clothes. After the heat release chamber 3 heats the inhaled air, the high-temperature gas passes through the air inlet pipe 38 and the air inlet 36 in sequence and then enters the drying machine body 22. Under the action of high temperature, textile products such as clothes are dried, and the residual heat gas after drying flows back to the heat absorption chamber 2 through the return air port 37 and the heat recovery pipe 12, and this is repeated.

[0051] See also Figure 1 and Figure 6 Since there are many impurities such as cloth scraps on the surface of textiles such as clothes, the waste heat air carries impurities such as cloth scraps when it refluxes. For this reason, a filter screen 23 is fixedly installed in the heat recovery pipe 12, and a collection box 24 is installed on the bottom surface of the heat recovery pipe 12 by bolts, and the collection box 24 is located on the side of the windward side of the filter screen 23.

[0052] In addition, in order to facilitate scraping of impurities such as cloth scraps adhering to the windward surface of the filter 23, the heat recovery pipe 12 is installed with a cleaning mechanism, which includes a scraper 25. The middle part of the filter 23 is rotatably connected to a rotating shaft 26, and both ends of the rotating shaft 26 extend outside the side wall of the filter 23. The scraper 25 is fixedly connected to one end of the rotating shaft 26 facing the windward surface, and the scraper 25 is attached to the windward surface of the filter 23. The end of the rotating shaft 26 away from the windward surface is coaxially fixedly connected to a fan body 27. A material guide groove 28 is provided on one side of the windward surface of the filter 23, and the material guide groove 28 is inclined toward the direction of the collection box 24.

[0053] When the waste heat gas refluxes in the heat recovery pipe 12, the gas drives the fan body 27 to rotate, and the fan body 27 drives the scraper 25 to rotate through the rotating shaft 26, so that the scraper 25 scrapes the windward surface of the filter 23. Under the continuous rotation of the scraper 25, the scraper 25 scrapes impurities such as cloth scraps adhering to the windward surface of the filter 23 into the material guide trough 28.

[0054] join Figure 6 and Figure 7 In order to further push away impurities such as cloth scraps in the guide trough 28, the filter screen 23 is also equipped with a push assembly, which includes a push block 29. The push block 29 is slidably installed in the guide trough 28, and a connecting rod 30 is fixedly connected to one side of the push block 29. The end of the connecting rod 30 away from the push block 29 penetrates and extends outside the filter screen 23, and the connecting rod 30 is slidably connected to the filter screen 23. The end of the connecting rod 30 away from the push block 29 is fixedly connected to a pull rod 31, which is vertically arranged, and the bottom end of the pull rod 31 extends outside the heat recovery pipe 12.

[0055] In addition, the heat recovery pipe 12 is also equipped with an elastic member, which is used to cooperate with the pull rod 31 to move. The elastic member is a first spring 32, which is installed on one side of the pull rod 31, and one end of the first spring 32 is fixedly connected to the side wall of the pull rod 31, and the other end of the first spring 32 is fixedly connected to the inner bottom wall of the heat recovery pipe 12.

[0056] When the pull rod 31 is pulled downward, the pull rod 31 squeezes the first spring 32, and the pull rod 31 drives the push block 29 downward through the connecting rod 30. At this time, the push block 29 slides along the inner wall of the guide groove 28, and pushes down the impurities adhering to or retained in the guide groove 28, and finally collects them in the collection box 24. When the pull rod 31 is released, the first spring 32 releases its elastic force and drives the pull rod 31 to move upward. The pull rod 31 drives the push block 29 upward through the connecting rod 30. At this time, the push block 29 impacts the filter screen 23, and the dust and impurities on the filter screen 23 are shaken off by the impact vibration force.

[0057] It should be noted that see Figure 7 and Figure 8The connecting rod 30 includes a barrel 33, a rod 34 and a second spring 35. The rod 34 is slidably connected to the barrel 33, one end of the rod 34 extends outside the barrel 33, and one end of the rod 34 is fixedly connected to the pusher block 29. One end of the barrel 33 away from the rod 34 is fixedly connected to the pull rod 31. The second spring 35 is installed in the barrel 33, and one end of the second spring 35 is fixedly connected to the inner wall of the barrel 33, and the other end of the second spring 35 is fixedly connected to one end of the rod 34.

[0058] Since the guide slot 28 is tilted toward the collecting box 24, when the pusher block 29 descends, the pusher block 29 stretches the rod 34, and the rod 34 in turn stretches the second spring 35. When the pusher block 29 ascends, the second spring 35 releases its elastic force and drives the rod 34 to retract to the barrel 33, and the rod 34 drives the pusher block 29 to always press against the slot wall of the guide slot 28, thereby ensuring the stability of the pusher block 29 when in use.

[0059] At the same time, since the pull rod 31 is installed in close contact with the side of the filter 23 away from the windward surface, the pull rod 31 blocks the portion where the connecting rod 30 passes through the filter 23, thereby improving the filtering stability of the filter 23.

[0060] Working principle of a heat pump dryer with multi-stage waste heat recovery:

[0061] The heat recovery pipe 12 is used to dry textile products such as clothes. After the heat release chamber 3 heats the inhaled air, the high-temperature gas passes through the air inlet pipe 38 and the air inlet 36 in sequence and then enters the drying machine body 22. Under the action of high temperature, textile products such as clothes are dried, and the residual heat gas after drying flows back to the heat absorption chamber 2 through the return air port 37 and the heat recovery pipe 12, and this is repeated.

[0062] Since there are relatively many impurities such as cloth scraps on the surface of textiles such as clothes, the waste heat air often carries impurities such as cloth scraps when it refluxes. When the waste heat gas refluxes in the heat recovery pipe 12, the gas drives the fan body 27 to rotate, and the fan body 27 drives the scraper 25 to rotate through the rotating shaft 26. The scraper 25 scrapes the windward surface of the filter 23. Under the continuous rotation of the scraper 25, the scraper 25 scrapes the impurities such as cloth scraps adhering to the windward surface of the filter 23 into the material guide trough 28.

[0063] When the impurities in the guide trough 28 need to be collected in the collection box 24, the pull rod 31 is pulled downward, the pull rod 31 squeezes the first spring 32, and the pull rod 31 drives the push block 29 to descend through the connecting rod 30. At this time, the push block 29 slides along the inner wall of the guide trough 28, and pushes down the impurities adhering to or retained in the guide trough 28, and finally collects them in the collection box 24. When the pull rod 31 is released, the first spring 32 releases its elastic force and drives the pull rod 31 to move upward. The pull rod 31 drives the push block 29 to rise through the connecting rod 30. At this time, the push block 29 impacts the filter screen 23, and the dust and impurities on the filter screen 23 are shaken off by the impact vibration force.

[0064] In summary, 1) the waste heat gas enters the heat absorption chamber 2 through the heat recovery pipe 12, and passes through the first-stage evaporator 6, the second-stage evaporator 7, the third-stage evaporator 8 and the fourth-stage evaporator 9 in sequence. The waste heat gas is continuously heat-transferred through the successive evaporators, and the gas after heat exchange and cooling is finally discharged from the exhaust port 5. This process ensures that the heat of the waste heat gas is completely recovered to the evaporator, thereby improving the heat recovery rate.

[0065] 2) Impurities such as cloth scraps in the waste heat gas are filtered through the filter screen 23 and collected through the collection box 24, which is helpful to reduce the impurities such as cloth scraps entering the heat absorption chamber 2, thereby affecting the normal use of evaporators at all levels.

[0066] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A heat pump dryer with multi-stage waste heat recovery, comprising a frame (1), characterized in that: The frame (1) is provided with a heat absorption chamber (2) and a heat release chamber (3), and the heat absorption chamber (2) is provided with a first-stage evaporator (6), a second-stage evaporator (7), a third-stage evaporator (8) and a fourth-stage evaporator (9) in sequence from bottom to top. The frame (1) is provided with a mounting plate (10), and a heat recovery centrifugal fan (11) is provided on the mounting plate (10). The air outlet end of the heat recovery centrifugal fan (11) is connected to the heat absorption chamber (2). The side wall of the frame (1) is provided with an exhaust port (5), and the exhaust port (5) is connected to the heat absorption chamber (2). The first-stage evaporator (6) is connected to the first-stage evaporator (6); a first-stage heat release module (13), a second-stage heat release module (14), a third-stage heat release module (15) and a fourth-stage heat release module (16) are respectively arranged in the frame (1) corresponding to the first-stage evaporator (6), the second-stage evaporator (7), the third-stage evaporator (8) and the fourth-stage evaporator (9); the first-stage heat release module (13), the second-stage heat release module (14), the third-stage heat release module (15) and the fourth-stage heat release module (16) are all connected to the heat release chamber (3); It also comprises a drying machine body (22), the drying machine body (22) being respectively provided with an air inlet (36) and an air return port (37), an air inlet pipe (38) being connected between the frame (1) and the air inlet (36), and a heat recovery pipe (12) being connected between the air inlet end of the heat recovery centrifugal fan (11) and the air return port (37); A filter screen (23) is provided in the heat recovery pipe (12); a collection box (24) is provided on the bottom surface of the heat recovery pipe (12) for removal; the collection box (24) is located on the windward side of the filter screen (23); and a cleaning mechanism for scraping off impurities is provided on the heat recovery pipe (12); The cleaning mechanism comprises a scraper (25), the middle part of the filter (23) is rotatably connected to a rotating shaft (26), the scraper (25) is arranged at one end of the rotating shaft (26), the scraper (25) is attached to the windward surface of the filter (23), the other end of the rotating shaft (26) is provided with a fan body (27), the windward surface of the filter (23) is provided with a material guide groove (28), the material guide groove (28) is inclined toward the direction of the collection box (24), and the filter (23) is provided with a material pushing component for scraping off sticky impurities in the material guide groove (28); The pushing assembly comprises a pushing block (29), the pushing block (29) is slidably arranged in the material guide groove (28), a connecting rod (30) is arranged on one side of the pushing block (29), the connecting rod (30) extends outside the filter screen (23), the connecting rod (30) is slidably connected to the filter screen (23), a pull rod (31) is arranged at one end of the connecting rod (30), the bottom end of the pull rod (31) extends outside the heat recovery pipe (12), and the heat recovery pipe (12) is provided with an elastic member for cooperating with the pull rod (31) to be pulled; The elastic member is a first spring (32), the first spring (32) is arranged on one side of the pull rod (31), one end of the first spring (32) is fixedly connected to the side wall of the pull rod (31), and the other end of the first spring (32) is fixedly connected to the inner bottom wall of the heat recovery pipe (12); The connecting rod (30) comprises a cylinder (33), a rod (34) and a second spring (35); the rod (34) is slidably connected to the cylinder (33); the second spring (35) is arranged in the cylinder (33); one end of the second spring (35) is fixedly connected to the inner wall of the cylinder (33); and the other end of the second spring (35) is fixedly connected to one end of the rod (34).

2. The heat pump dryer with multi-stage waste heat recovery according to claim 1, characterized in that: A subcooler (17) is provided between the first-stage evaporator (6) and the second-stage evaporator (7), and the subcooler (17) is respectively connected between the third-stage evaporator (8) and the third-stage heat release module (15), and between the fourth-stage evaporator (9) and the fourth-stage heat release module (16).

3. The heat pump dryer with multi-stage waste heat recovery according to claim 1, characterized in that: The first-stage heat release module (13), the second-stage heat release module (14), the third-stage heat release module (15), and the fourth-stage heat release module (16) respectively include a condenser (18), a compressor (19), a gas-liquid separator (20), and an expansion valve (21); the compressor (19), the condenser (18), the expansion valve (21), evaporators of each stage, and the gas-liquid separator (20) are connected in sequence through pipelines.

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