JP2014204883A - Heat pump drying machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat pump drying machine capable of operating safely while suppressing deterioration of drying efficiency.SOLUTION: A heat pump drying machine includes: a drying chamber; a circulation air path; a heat pump unit; temperature detection means; and a control device. The heat pump unit is configured by annularly connecting a condenser provided in the circulation air path and heating air in the circulation air path, an evaporator provided in the circulation air path and dehumidifying the air inside the circulation air path, a decompression device provided between the evaporator and the condenser and a compressor provided outside of the circulation air path and supplying a cooling medium. The heat pump unit has: pressure difference adjustment means for balancing pressure difference between a suction side and a discharge side of the compressor while the compressor is stopped; blocking means for blocking movement of the cooling medium from the condenser side to the evaporator side while the compressor is stopped; and a check valve provided between the evaporator and the compressor and preventing backflow of the cooling medium from the compressor side to the evaporator side. The control device stops the compressor temporarily based on the detection temperature of the temperature detection means during a drying step.

Description

  Embodiments described herein relate generally to a heat pump dryer.

  In recent years, an increasing number of dryers adopt a heat pump method as a heating method of warm air for drying. The heat pump type dryer has an advantage that it can be dried at a lower temperature than the heater type, so that there is less damage to clothing due to heat, and less power consumption and energy saving. The heat pump dryer includes a heat pump unit that includes an evaporator and a condenser as heat exchangers, a compressor that supplies refrigerant, and the like. The heat pump dryer connects a drying chamber in which clothes are stored and a heat exchanger with a circulation air passage. And a heat pump type dryer operates the refrigerating cycle by a heat pump unit, and circulates air between a drying chamber and a heat exchanger via a circulation wind path. This circulating air deprives moisture from clothes in the drying chamber, and is dehumidified and heated by a heat exchanger to become hot air of low humidity and is supplied to the drying chamber again. As a result, the clothes in the drying chamber are dried.

  However, in such a configuration, heat generated by the compressor is accumulated in the air in the circulation air passage. Therefore, as the drying proceeds, the temperature of the condenser and the evaporator rises, and as the temperature of the condenser and the evaporator rises, the temperature of the compressor also rises. Here, in order to operate the heat pump unit safely, it is necessary that the temperature of the compressor does not exceed the upper limit determined for safety. For this reason, when the temperature of the compressor exceeds a predetermined temperature, it is conceivable that the compressor is temporarily stopped and cooled. However, if the compressor is temporarily stopped, it takes time for the heat pump unit to start up when the compressor is restarted thereafter, and as a result, there is a possibility that the drying efficiency is lowered.

JP 2000-186863 A

  Then, the heat pump dryer which can be drive | operated safely, suppressing the fall of the drying efficiency of a heat pump unit is provided.

  The heat pump dryer of the present embodiment includes a drying chamber having an exhaust port and an air supply port, a circulation air path provided outside the drying chamber and connecting the exhaust port and the air supply port, A heat pump unit that dehumidifies and heats the air; temperature detection means that detects a temperature of the heat pump unit; and a control device that controls the heat pump unit to perform a drying process. The heat pump unit includes a condenser that is provided in the circulation air passage and heats the air in the circulation air passage, an evaporator that is provided in the circulation air passage and dehumidifies the air in the circulation air passage, A decompression device provided between the evaporator and the condenser, and a compressor that is provided outside the circulation air passage and that supplies the refrigerant are connected in a ring shape, and the compressor is stopped. Pressure difference adjusting means for balancing the pressure difference between the suction side and the discharge side of the compressor, and a blocking means for blocking the movement of the refrigerant from the condenser side to the evaporator side while the compressor is stopped. And a check valve that is provided between the evaporator and the compressor and prevents a reverse flow of refrigerant from the compressor side to the evaporator side. The controller temporarily stops the compressor based on the temperature detected by the temperature detecting means during the drying process.

1 is a longitudinal side view showing a schematic configuration of a heat pump dryer according to the first embodiment. Longitudinal rear view showing schematic configuration of heat pump dryer Diagram showing schematic configuration of heat pump unit Block diagram showing the configuration of the control system The figure which shows the open / close state of the 1st on-off valve and the 2nd on-off valve with respect to the drive of a compressor The flowchart which shows the control content of the drying process by a control apparatus Flow chart showing control contents of circulation fan control determination Flow chart showing control contents of compressor stop determination FIG. 7 equivalent diagram according to the second embodiment Equivalent to FIG. FIG. 3 equivalent diagram according to the third embodiment 4 equivalent diagram 6 equivalent diagram Flow chart showing control contents of cooling fan drive determination

  Hereinafter, a heat pump dryer according to a plurality of embodiments will be described with reference to the drawings. In addition, in each embodiment, the same code | symbol is attached | subjected to the substantially same component and description is abbreviate | omitted.

(First embodiment)
First, a first embodiment will be described with reference to FIGS.
As shown in FIG. 1, a washing dryer 10 as a heat pump dryer includes an outer box 11, a water tank 12, a rotating tank 13, a motor 14, and a door 15. In the present embodiment, the door 15 side with respect to the outer box 11 is the front side of the washing / drying machine 10. The washing / drying machine 10 is a so-called drum-type washing / drying machine having a heat pump-type drying function and in which the rotation axis of the rotary tank 13 is inclined with respect to the ground. The outer box 11 is formed in a substantially rectangular box shape using a steel plate or the like. The water tank 12 is housed inside the outer box 11. The rotary tank 13 is accommodated in the water tank 12. Both the water tank 12 and the rotating tank 13 are formed in a cylindrical shape.

  The water tank 12 has an opening 121 at one end of a cylindrical shape, and a water tank end plate 122 at the other end. The opening 121 is located above the water tank end plate 122 in the inclined water tank 12. Similarly, the rotating tank 13 has an opening 131 formed at one end of a cylindrical shape, and a rotating tank end plate 132 provided at the other end. The opening 131 is located above the rotating tank end plate 132 in the inclined rotating tank 13. The opening 131 of the rotating tank 13 is covered with the opening 121 of the water tank 12. The water tank 12 and the rotating tank 13 function as a drying chamber for storing clothes.

  The water tank 12 has an exhaust port 16 and an air supply port 17. The exhaust port 16 is provided in the upper front portion of the peripheral wall constituting the cylindrical portion of the water tank 12. The air supply port 17 is in the water tank end plate 122 and is provided at a portion slightly above the center of the water tank end plate 122. The exhaust port 16 and the air supply port 17 communicate the inside and the outside of the water tank 12.

  The water tank 12 has a drainage part 18 on the rear end side of the bottom part located below the gravity direction. The drainage unit 18 is located below the exhaust port 16 and the air supply port 17. The drainage unit 18 includes a drainage port 123, a drainage valve 19, and a drainage hose 20. By opening the drain valve 19, the water in the water tank 12 is discharged from the drain port 123 to the outside of the washing / drying machine 10 via the drain valve 19 and the drain hose 20.

  The rotary tank 13 has a plurality of holes 21 and a plurality of communication ports 22. The hole 21 and the communication port 22 communicate the inside and the outside of the rotary tank 13. The hole 21 is formed in the whole area of the peripheral wall which comprises the cylindrical cylindrical part of the rotating tank 13. As shown in FIG. The communication port 22 is formed in the entire area of the rotary tank end plate 132. The hole 21 and the communication port 22 mainly function as a water passage through which water enters and exits during a washing operation and a dehydration operation, and function as a ventilation hole through which air enters and exits during a drying operation. In FIG. 1, only a part of the plurality of holes 21 and the communication ports 22 is shown for simplicity. Further, although not shown in detail, the rotating tub 13 is provided with a plurality of baffles inside the cylindrical portion. The baffle stirs the laundry stored inside the rotating tub 13.

  The motor 14 is provided on the water tank end plate 122 outside the water tank 12. The motor 14 is, for example, an outer rotor type DC brushless motor. The shaft portion 141 of the motor 14 passes through the water tank end plate 122 and protrudes to the inside of the water tank 12, and is fixed to the center portion of the rotary tank end plate 132. Thereby, the motor 14 rotates the rotation tank 13 relatively with respect to the water tank 12. In this case, the shaft portion 141, the rotation axis of the rotary tank 13, and the central axis of the water tank 12 are in agreement.

  The door 15 is provided on the outer surface side of the outer box 11 via a hinge (not shown). The door 15 rotates about a hinge as a fulcrum, and opens and closes an opening (not shown) formed on the front surface of the outer box 11. The opening formed in the outer box 11 is connected to the opening 121 of the water tank 12 by a bellows 112. Laundry such as clothes is put into and out of the rotating tub 13 through the openings 121 and 131 with the door 15 opened.

  The washing / drying machine 10 includes a control device 23 and an operation panel 24 shown in FIG. 4, and a water supply device 25 shown in FIG. The control device 23 includes a microcomputer and controls the overall operation of the washing / drying machine 10. As shown in FIG. 1, the operation panel 24 is provided in front of the outer box 11 and on the upper side of the door 15. As shown in FIG. 4, the operation panel 24 is connected to the control device 23, and the user performs various settings such as selection of a driving course by operating the operation panel 24.

  As shown in FIG. 2, the water supply device 25 includes a water supply case 26, a water supply valve 27, a water supply hose 28, and the like. The water supply valve 27 is connected to the control device 23 and is opened and closed under the control of the control device 23. One end of the water supply hose 28 is connected to the water supply valve 27 and the other end is connected to an external water source such as a water supply. The control device 23 opens and closes the water supply valve 27 to supply water from the water source into the water tank 12 through the water supply hose 28, the water supply valve 27, and the water supply case 26.

  The washing / drying machine 10 includes a circulation air passage 30 as shown in FIG. The circulation air passage 30 connects the exhaust port 16 and the air supply port 17 outside the water tank 12. Specifically, the circulation air passage 30 includes an exhaust duct 31, a filter device 32, a connection duct 33, a heat exchange unit 34, and an air supply duct 35.

  As shown in FIG. 1, the exhaust duct 31 connects the exhaust port 16 of the water tank 12 and the filter device 32. The exhaust duct 31 is composed of, for example, a bellows-like hose. The filter device 32 is provided inside the outer box 11 and above the water tank 12 and the rotary tank 13. A filter 321 is provided in the filter device 32. When the air exhausted from the exhaust port 16 passes through the filter 321 of the filter device 32, foreign matters such as lint are removed.

  The filter device 32 is connected to the upstream side of the heat exchanging section 34 via the connection duct 33. The heat exchanging part 34 is provided in the lower part inside the outer box 11 and below the filter device 32, the water tank 12, and the rotating tank 13. The heat exchanging unit 34 generates dry hot air by dehumidifying and heating the air passing through the inside. An evaporator 41 and a condenser 42 constituting the heat pump unit 40 are provided in the heat exchange unit 34. The evaporator 41 is provided on the upstream side of the condenser 42 with respect to the air flow in the heat exchange unit 34 during the drying operation. The air passing through the heat exchange section 34 is cooled by the evaporator 41 and dehumidified thereby. The air dehumidified by the evaporator 41 is then heated by the condenser 42 to become hot air.

  The downstream side of the heat exchange unit 34 is connected to the air supply port 17 of the water tank 12 through the air supply duct 35. A circulation fan 36 is provided at a connection portion between the heat exchange unit 34 and the air supply duct 35. The circulation fan 36 is composed of, for example, a sirocco fan. The circulation fan 36 is configured such that the rotation speed can be changed by the control of the control device 23. The circulation fan 36 sucks the air in the heat exchanging section 34 and discharges it to the air supply duct 35 side. Thereby, the flow of the air which circulates through the water tank 12 and the circulation air path 30 arises as shown by the arrow A of FIG.1, FIG2 and FIG.3. In this case, when the air flow in the circulation air passage 30 is viewed, the exhaust port 16 is on the most upstream side, and the air supply port 17 is on the most downstream side.

  In this configuration, when the compressor 43 and the circulation fan 36 are driven, the warm air dehumidified and heated in the heat exchanging section 34 is supplied through the air supply duct 35 by the air blowing action of the circulation fan 36. To the water tank 12. Thereafter, the warm air mainly enters the rotary tub 13 from the communication port 22, deprives moisture from the laundry in the rotary tub 13, and then mainly exits from the hole 21 to the outside of the rotary tub 13. The air containing moisture is sucked into the circulation air passage 30 from the exhaust port 16. The air sucked into the circulation air passage 30 first passes through the exhaust duct 31 and the filter device 32. Thereafter, it flows to the heat exchanging section 34 through the connection duct 33. As described above, the drying operation is performed by circulating air between the water tank 12 and the circulation air passage 30 and dehumidifying and heating the air in the circulation air passage 30.

  Next, the heat pump unit 40 will be described. As shown in FIG. 3, the heat pump unit 40 includes a compressor 43 and a decompression device 44 in addition to an evaporator 41 and a condenser 42. The compressor 43 and the decompression device 44 are provided outside the heat exchange unit 34. The heat pump unit 40 is configured by annularly connecting a condenser 42, a decompression device 44, and an evaporator 41 in the order in which the refrigerant flows with respect to the compressor 43. The evaporator 41 and the condenser 42 are configured by, for example, a tube having a large number of fins provided at minute intervals. By flowing a refrigerant through the tube, heat between the air passing between the fins and the refrigerant is obtained. Exchange. The evaporator 41 and the condenser 42 function as a heat exchanger.

  The compressor 43 supplies the refrigerant to the condenser 42 by pressure feeding. The compressor 43 is connected to the control device 23 and is driven and stopped under the control of the control device 23. The compressor 43 is driven at a constant frequency according to the frequency of the supplied AC power supply, for example. An accumulator 45 is provided on the suction side 431 of the compressor 43. The accumulator 45 suppresses the pressure fluctuation of the refrigerant flowing into the compressor 43. The decompression device 44 decompresses the high-pressure liquid refrigerant discharged from the condenser 42 to make a low-pressure gas-liquid mixed state. In this case, the decompression device 44 is constituted by a capillary tube, for example, but may be an expansion valve or the like.

  The heat pump unit 40 has a bypass 46, a first on-off valve 47, a second on-off valve 48, and a check valve 49. The bypass circuit 46 is a metal pipe, for example, and bypasses the compressor 43 to connect the suction side 431 and the discharge side 432 of the compressor 43. The first on-off valve 47 is provided in the middle part of the bypass 46. The first opening / closing valve 47 is, for example, an electromagnetic valve, and opens / closes the bypass 46.

  The second on-off valve 48 is, for example, an electromagnetic valve, and is provided between the condenser 42 and the evaporator 41, in this case, between the pressure reducing device 44 and the evaporator 41. As shown in FIG. 4, the first on-off valve 47 and the second on-off valve 48 are connected to the control device 23 and are opened and closed based on control from the control device 23. The check valve 49 is provided between the evaporator 41 and the compressor 43, and prevents the refrigerant from flowing backward from the compressor 43 side to the evaporator 41.

  As shown in FIG. 5, the control device 23 closes the first on-off valve 47 and opens the second on-off valve 48 while the compressor 43 is being driven. In this state, a pressure difference is generated between the suction side 431 and the discharge side 432 of the compressor 43 by the pumping action of the compressor 43. The refrigerant discharged from the discharge side 432 of the compressor 43 passes through the condenser 42, the pressure reducing device 44, the second on-off valve 48, the evaporator 41, and the check valve 49 in this order, as indicated by an arrow B in FIG. It goes around and is sucked into the compressor 43 again. Thereby, the refrigeration cycle by the heat pump unit 40 is operated.

  While the compressor 43 is stopped, the control device 23 opens the first on-off valve 47 and closes the second on-off valve 48. That is, when looking at the periphery of the compressor 43 when the compressor 43 is stopped, the high-temperature and high-pressure refrigerant on the discharge side 432 of the compressor 43 passes through the bypass 46 as shown by an arrow C in FIG. As a result, the refrigerant flows to the suction side 431 of the compressor 43 having a lower pressure than the condenser 42 side. Thereby, the pressure difference between the suction side 431 and the discharge side 432 of the compressor 43 is eliminated. In this case, the bypass 46 and the first on-off valve 47 function as a pressure difference adjusting unit that adjusts the pressure difference between the suction side 431 and the discharge side 432 of the compressor 43 while the compressor 43 is stopped. .

  On the other hand, when the periphery of the decompression device 44 when the compressor 43 is stopped is viewed, the high-temperature and high-pressure refrigerant remaining on the upstream side of the decompression device 44, that is, on the condenser 42 side, is blocked by the second on-off valve 48. Therefore, it does not flow to the downstream side of the decompression device 44, that is, the evaporator 41 side. Therefore, the pressure difference between the evaporator 41 and the condenser 42 is maintained in a state close to the state before the compressor 43 is stopped. In this case, the second on-off valve 48 functions as a blocking means that blocks the movement of the refrigerant from the condenser 42 side to the evaporator 41 side while the compressor 43 is stopped. In addition, when the decompression device 44 is an expansion valve whose throttle opening can be controlled to be substantially zero, the expansion valve can function as a shut-off means.

  As shown in FIGS. 3 and 4, the washing / drying machine 10 includes an air inlet temperature sensor 51, an exhaust outlet temperature sensor 52, a compressor temperature sensor 53, a condenser temperature sensor 54, an evaporator inlet temperature sensor 55, and evaporation. A vessel outlet temperature sensor 56 is provided. The inlet temperature sensor 51, the outlet temperature sensor 52, the compressor temperature sensor 53, the condenser temperature sensor 54, the evaporator inlet temperature sensor 55, and the evaporator outlet temperature sensor 56 each directly or directly adjust the temperature of the heat pump unit 40. It functions as a temperature detection means for detecting indirectly and is connected to the control device 23 respectively.

  As shown in FIG. 3, the supply air temperature sensor 51 and the exhaust air temperature sensor 52 are provided in the circulation air passage 30 and detect the temperature of the air in the circulation air passage 30. Among these, the air inlet temperature sensor 51 is provided between the condenser 42 and the air inlet 17 and in the vicinity of the air inlet 17. The air inlet temperature sensor 51 passes through the air supply duct 35 and is supplied to the water tank 12 and the rotary tank 13 serving as the drying chamber, that is, the temperature of the air heated by the heat exchange unit 34 and supplied to the drying chamber. Is detected. The exhaust port temperature sensor 52 is provided between the evaporator 41 and the exhaust port 16 and in the vicinity of the exhaust port 16. The exhaust port temperature sensor 52 detects the temperature of air that is exhausted from the water tank 12 and the rotary tank 13 that are drying chambers and passes through the exhaust duct 31.

  The compressor temperature sensor 53 is provided in the refrigerant pipe on the discharge side 432 of the compressor 43 and detects the temperature of the refrigerant discharged from the compressor 43, that is, the temperature of the compressor 43. The condenser temperature sensor 54 is provided at the center of the condenser 42 and detects the temperature of the condenser 42. The evaporator inlet temperature sensor 55 is provided on the refrigerant inlet side with respect to the evaporator 41 and detects the temperature of the inlet side portion of the evaporator 41. The evaporator outlet temperature sensor 56 is provided on the outlet side of the refrigerant with respect to the evaporator 41 and detects the temperature of the outlet side portion of the evaporator 41.

  The control device 23 can selectively execute a washing operation, a drying operation, and a washing operation. Among these, the drying process performed by drying operation and washing-drying operation is demonstrated with reference to FIGS. In the drying process, the heat pump unit 40 and the circulation fan 36 are driven. And the warm air dehumidified and heated by the heat pump unit 40 is supplied into the water tank 12, and thereby the drying of the clothes in the rotary tank 13 is advanced. In order to operate the heat pump unit 40 safely, the control device 23 stops and restarts the compressor 43 and increases or decreases the rotational speed of the circulation fan 36 based on the detected temperature Ta of the compressor temperature sensor 53 during the drying process. I do.

  That is, the first dryer stop temperature T1, the first circulation fan determination temperature T2, and the first compressor restart temperature T3 are set in the washer / dryer 10 on the basis of the compressor upper limit temperature T. The compressor upper limit temperature T is an upper limit temperature of the compressor 43 that can drive the heat pump unit 40 safely. In the case of this embodiment, the compressor upper limit temperature T is set to 105 ° C. The first compressor stop temperature T <b> 1 is a temperature of the compressor 43 that is a determination criterion for temporarily stopping the compressor 43, and is set to a temperature lower than the compressor upper limit temperature T by a predetermined temperature. In the present embodiment, the first compressor stop temperature T1 is set to 100 ° C., which is 5 ° C. lower than the compressor upper limit temperature T.

  The first circulation fan determination temperature T <b> 2 is the temperature of the compressor 43 that serves as a determination criterion for increasing or decreasing the rotation speed of the circulation fan 36. The first compressor restart temperature T3 is the temperature of the compressor 43 that serves as a determination criterion for restarting the temporarily stopped compressor 43. The first circulation fan determination temperature T2 and the first compressor restart temperature T3 are set to a temperature that is lower by a predetermined temperature than the first compressor stop temperature T1. In the present embodiment, the first circulation fan determination temperature T2 and the first compressor restart temperature T3 are set to 95 ° C., which is 5 ° C. lower than the first compressor stop temperature T1.

  When the compressor 43 is being driven in the drying process, the control device 23 determines that the temperature of the compressor 43, that is, the compressor temperature Ta by the compressor temperature sensor 53 exceeds the first circulation fan determination temperature T2 (= 95 ° C.). The rotational speed of the circulation fan 36 is increased. Thereby, the air volume in the circulation air path 30 is increased, and the heat transfer in the circulation air path 30 is promoted, thereby suppressing the temperature rise of the compressor 43. Furthermore, when the compressor temperature Ta exceeds the first compressor stop temperature T1 (= 105 ° C.) while the compressor 43 is being driven in the drying process, the control device 23 temporarily stops the compressor 43. Thereby, the heat generation by the compressor 43 is stopped, and the compressor 43 is cooled. When the control device 23 determines that the compressor temperature Ta by the compressor temperature sensor 53 has become equal to or lower than the first compressor restart temperature T3 (= 95 ° C.), the controller 43 restarts the compressor 43.

  Specifically, as shown in FIG. 6, when starting the drying process (start), the control device 23 first drives the compressor 43 at a constant rotational speed and drives the circulation fan 36 in step S11. . In this case, the rotation speed F of the circulation fan 36 is set to an initial value F0 = 4500 rpm. At this time, the first on-off valve 47 is closed, and the second on-off valve 48 is opened.

  Next, in step S12, the control device 23 determines whether or not the drying process end condition is satisfied. If the completion | finish conditions of the drying process are satisfy | filled (it is YES at step S12), the control apparatus 23 will transfer to step S15, will stop the compressor 43 and the circulation fan 36, and will complete | finish a drying process (end). On the other hand, when the termination condition for the drying process is not satisfied (NO in step S12), the control device 23 proceeds to step S13. The end condition of the drying process is, for example, whether the drying process time set in advance by the weight of clothes accommodated in the rotary tank 13 or the operation of the user has elapsed, or the supply air temperature sensor 51 and the exhaust air temperature sensor This is determined based on whether or not the temperature difference detected at 52 has converged within a predetermined range.

  Next, in step S13, the control device 23 executes a circulation fan control determination. In the circulation fan control determination, the control device 23 determines whether or not the compressor temperature Ta exceeds the first circulation fan determination temperature T2 (= 95 ° C.), and increases or decreases the rotation speed of the circulation fan 36. Specifically, when the circulation fan control determination is executed, as shown in FIG. 7, the controller 23 determines that the current rotational speed F of the circulation fan 36 is greater than the initial value F0 (= 4500 rpm) in step S21. Judge whether it is large or not. Thus, the control device 23 determines whether or not the rotational speed F of the circulation fan 36 is currently increased by executing the circulation fan control determination before the current time.

  When the current rotational speed F of the circulation fan 36 is larger than the initial value F0 (= 4500 rpm) (YES in step S21), the control device 23 increases the rotational speed F of the circulation fan 36 by executing the circulation fan control determination. The process proceeds to step S22. In step S22, the control device 23 determines whether or not a predetermined time, for example, 1 minute has elapsed since the rotation speed F of the circulation fan 36 was increased by the previous execution of the circulation fan control determination. This is because when the rotational speed F of the circulation fan 36 is once increased by execution of the circulation fan control determination, the increased rotational speed F is maintained for at least a predetermined time, in this case, 1 minute. If one minute has elapsed since the increase in the rotational speed F (YES in step S22), the control device 23 proceeds to step S23. On the other hand, if one minute has not elapsed since the increase in the rotation speed F (NO in step S22), the control device 23 proceeds to step S14 shown in FIG. 6 in order to maintain the current rotation speed F after the increase. Transition (return).

  In step S21, the control device 23 determines that the rotation speed F of the circulation fan 36 is not increased when the current rotation speed F of the circulation fan 36 does not exceed the initial value F0 (= 4500 rpm) (NO). Determination is made, and the process proceeds to step S23. In step S23, the controller 23 determines whether or not the compressor temperature Ta exceeds the first circulation fan determination temperature T2 (= 95 ° C.).

  When the compressor temperature Ta exceeds the first circulation fan determination temperature T2 (= 95 ° C.) (YES in step S23), the control device 23 proceeds to step S24 and sets the rotation speed F of the circulation fan 36 to, for example, 250 rpm. Increase. In step S24, when the increased rotation speed F exceeds the maximum rotation speed Fmax of the circulation fan 36, for example, 5500 rpm, the rotation speed F is set to Fmax (= 5500 rpm). Thereafter, the control device 23 proceeds to step S14 in FIG. 6 (return).

  On the other hand, if the compressor temperature Ta does not exceed the first circulation fan determination temperature T2 (= 95 ° C.) in step S23 (NO), the control device 23 proceeds to step S25. And the control apparatus 23 sets the rotation speed F of the circulation fan 36 to the initial value F0. As a result, the rotational speed F of the circulation fan 36 is returned to the initial value F0 if it has been increased by the previous execution of the circulation fan control determination, and is maintained at the initial value F0 if it has not been increased. Thereafter, the control device 23 proceeds to step S14 in FIG. 6 (return).

  Next, the control apparatus 23 performs a compressor stop determination in step S14 of FIG. In the compressor stop determination, the control device 23 determines whether or not the compressor temperature Ta exceeds the first compressor stop temperature T1 (= 100 ° C.), and if it exceeds, the compressor 43 is temporarily stopped. If not, the compressor 43 continues to be driven.

  Specifically, when the compressor stop determination is executed, the control device 23 determines whether or not the compressor 43 is stopped in step S31 as shown in FIG. Thus, the control device 23 determines whether or not the compressor 43 is currently stopped by executing the compressor stop determination before this time. If the compressor 43 is currently stopped (YES in step S31), the control device 23 proceeds to step S34. On the other hand, if the compressor 43 is currently being driven (NO in step S31), the control device 23 proceeds to step S32.

  In step S32, the control device 23 determines whether or not the compressor temperature Ta exceeds the first compressor stop temperature T1 (= 100 ° C.). When the compressor temperature Ta does not exceed the first compressor stop temperature T1 (= 100 ° C.) (NO in step S32), the control device 23 indicates that the drive of the compressor 43 is stable within the normal temperature range. And the process proceeds to step S12 shown in FIG. 6 (return). On the other hand, when the compressor temperature Ta exceeds the first compressor stop temperature T1 (= 100 ° C.) (YES in step S32), the control device 23 determines that the drive of the compressor 43 has exceeded the normal temperature range. Then, the process proceeds to step S33.

  In step S33, the control device 23 temporarily stops the compressor 43 and reduces the rotational speed F of the circulation fan 36 to, for example, 3000 rpm, which is smaller than the initial value F0 (= 4500 rpm). Further, the control device 23 opens the first on-off valve 47 and closes the second on-off valve 48. When the first on-off valve 47 is opened, as indicated by an arrow C in FIG. 3, the refrigerant on the discharge side 432 of the compressor 43 moves to the suction side 431, and the suction side 431 and the discharge side 432 of the compressor 43 The pressure difference is eliminated. In this case, the pressure on the compressor 43 side is higher than the check valve 49 on the compressor 43 side. Therefore, even when the compressor 43 is stopped, the check valve 49 can be operated normally, thereby preventing the refrigerant on the compressor 43 side from moving to the evaporator 41 side.

  Further, when the second on-off valve 48 is closed, the movement of the refrigerant from the condenser 42 side to the evaporator 41 side is blocked. Therefore, during the stop of the compressor 43, the movement of heat from the condenser 42 side to the evaporator 41 side due to the movement of the refrigerant is suppressed. That is, while the compressor 43 is stopped, the relatively high-temperature refrigerant on the condenser 42 side stays on the condenser 42 side, while the relatively low-temperature refrigerant on the evaporator 41 side remains as it is. Stay on the side. Thereby, even when the compressor 43 is stopped, the condenser 42 can be maintained at a relatively high temperature, and the evaporator 41 can be maintained at a relatively low temperature. That is, even when the compressor 43 is stopped, the temperature difference between the condenser 42 and the evaporator 41 can be maintained and the air in the circulation air passage 30 can be dehumidified and heated to some extent. As a result, drying of clothes can be promoted even when the compressor 43 is temporarily stopped.

  Thereafter, the control device 23 proceeds to step S34 shown in FIG. 8, and determines whether or not a predetermined time, for example, one minute has elapsed since the compressor 43 was temporarily stopped in step S33. This is because, when the compressor 43 is temporarily stopped, the state where the compressor 43 is stopped is maintained for at least one minute, and the cooling of the compressor 43 is promoted. If the compressor 43 is temporarily stopped (YES in step S31), but the predetermined time has not elapsed since the temporary stop (NO in step S34), the control device 23 proceeds to step S12 shown in FIG. (Return) On the other hand, when the compressor 43 is temporarily stopped (YES in step S31) and a predetermined time has elapsed after the temporary stop (YES in step S34), the control device 23 proceeds to step S35.

  In step S35, the control device 23 determines whether or not the compressor temperature Ta is lower than the first compressor restart temperature T3 (= 95 ° C.). When the compressor temperature Ta is equal to or higher than the first compressor restart temperature T3 (= 95 ° C.) (NO in step S35), the control device 23 determines that the cooling of the compressor 43 is insufficient. In this case, the control device 23 proceeds to step S12 shown in FIG. 6 without restarting the compressor 43 in order to continue cooling the compressor 43 (return). On the other hand, when the compressor temperature Ta is equal to or lower than the first compressor restart temperature T3 (= 95 ° C.) (YES in step S35), the control device 23 determines that the compressor 43 is sufficiently cooled, and the step The process proceeds to S36 and the compressor 43 is restarted.

  In step S36, the control device 23 restarts the compressor 43 and drives the circulation fan 36 at the maximum rotational speed Fmax (= 5500 rpm). Further, the first on-off valve 47 is closed and the second on-off valve 48 is opened. Then, the refrigerant discharged from the discharge side 432 of the compressor 43 is again sucked into the compressor 43 through the condenser 42, the decompression device 44, the second on-off valve 48, the evaporator 41, and the check valve 49 in order. Such a circulation is performed. Thereby, the refrigerating cycle by the heat pump unit 40 is restarted. Thereafter, the process proceeds to step S12 in FIG. 6 (return), and steps S12 to S14 are repeated until the drying end condition is satisfied (YES in step S12).

  According to this, the first compressor stop temperature T1 is set to a value lower than the compressor upper limit temperature T, which is the upper limit temperature determined for safety of the compressor 43. Then, the controller 23 temporarily stops the compressor 43 when the compressor temperature Ta exceeds the first compressor stop temperature T1 while the compressor 43 is being driven. Thereby, the compressor 43 is not driven in a state where the compressor temperature Ta exceeds the compressor upper limit temperature T, and as a result, the heat pump unit 40 can be operated safely.

  The first circulation fan determination temperature T2 is set to a value lower than the first compressor stop temperature T1. And the control apparatus 23 increases the rotation speed F of the circulation fan 36, when the compressor temperature Ta exceeds the 1st circulation fan determination temperature T2 during the drive of the compressor 43 in a drying process. According to this, before the compressor temperature Ta exceeds 1st compressor stop temperature T1, the rotation speed F of the circulation fan 36 can be increased and the temperature rise of the compressor 43 can be suppressed. Therefore, the frequency at which the compressor 43 is stopped can be reduced, and the drying efficiency can be improved.

  The heat pump unit 40 includes a bypass 46 and a first on-off valve 47 as pressure difference adjusting means. The control device 23 opens the first on-off valve 47 while the compressor 43 is temporarily stopped. Then, the high-pressure refrigerant on the discharge side 432 of the compressor 43 flows to the suction side 431 of the compressor 43 through the bypass 46. As a result, the pressure difference between the suction side 431 and the discharge side 432 of the compressor 43 is adjusted to be balanced. According to this, when restarting the compressor 43, a sufficient amount of refrigerant is present on the suction side 431 of the compressor 43, so that the refrigerant is supplied with sufficient pressure from a relatively early stage after the restart. can do. Therefore, the heat pump unit 40 can be quickly started up after restarting. As a result, the compressor 43 can be driven safely while suppressing a decrease in drying efficiency.

  Moreover, the heat pump unit 40 has the 2nd on-off valve 48 as an interruption | blocking means. The control device 23 closes the second on-off valve 48 while the compressor 43 is temporarily stopped. Then, the movement of the refrigerant from the condenser 42 side to the evaporator 41 side is hindered. Thereby, a relatively high temperature refrigerant remains on the condenser 42 side, and a relatively low temperature refrigerant remains on the evaporator 41 side. Therefore, the temperature difference between the condenser 42 and the evaporator 41 can be maintained even when the compressor 43 is temporarily stopped. Therefore, the heat pump unit 40 can exhibit a certain degree of drying performance even during the temporary stop of the compressor 43. As a result, it is possible to further improve the drying efficiency while maintaining safety.

  Moreover, according to this structure, even if the rotation speed of the compressor 43 is fixed to the fixed rotation speed, the heat pump unit 40 can be made excellent in safety and drying performance. That is, the heat pump unit 40 can be made excellent in safety and drying performance without making it possible to change the rotation speed of the compressor 43 by an inverter or the like. As a result, an increase in cost due to the use of an inverter or the like can be suppressed.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIGS.
In the second embodiment, in addition to the processing of the first embodiment, the control device 23 stops and restarts the compressor 43 based on the detected temperature Sa of the condenser temperature sensor 54 and determines the rotational speed of the circulation fan 36. Increase or decrease.

  That is, in the washer / dryer 10, the second compressor stop temperature S1, the second circulation fan determination temperature S2, and the second compressor restart temperature S3 are set on the basis of the condenser upper limit temperature S. The condenser upper limit temperature S is the upper limit temperature of the condenser 42 that can drive the heat pump unit 40 safely. In this case, the condenser upper limit temperature S is set to 80 ° C. The second compressor stop temperature S <b> 1 is a temperature of the condenser 42 that is a determination criterion for temporarily stopping the compressor 43, and is set to a temperature lower than the condenser upper limit temperature S by a predetermined temperature. In this case, the second compressor stop temperature S1 is set to 75 ° C., which is 5 ° C. lower than the condenser upper limit temperature S.

  The second circulation fan determination temperature S <b> 2 is the temperature of the condenser 42 that serves as a determination criterion for increasing or decreasing the rotation speed of the circulation fan 36. The second compressor restart temperature S3 is the temperature of the condenser 42 that serves as a determination criterion for restarting the temporarily stopped compressor 43. The second circulation fan determination temperature S2 and the second compressor restart temperature S3 are set to a temperature that is lower by a predetermined temperature than the second compressor stop temperature S1. In this case, the second circulation fan determination temperature S2 and the second compressor restart temperature S3 are set to 70 ° C., which is 5 ° C. lower than the second compressor stop temperature S1.

  In this embodiment, step S26 is added to the circulation fan control determination of the first embodiment shown in FIG. 7 as shown in FIG. When the compressor temperature Ta does not exceed the first circulation fan determination temperature T2 (= 95 ° C.) in step S23 (NO), the control device 23 proceeds to step S26. When the condenser temperature Sa exceeds the second circulation fan determination temperature S2 (= 70 ° C.) (YES in step S26), the control device 23 proceeds to step S24 and sets the rotation speed F of the circulation fan 36. Increase. On the other hand, when the condenser temperature Sa does not exceed the second circulation fan determination temperature S2 (= 70 ° C.) in step S26 (NO), the control device 23 proceeds to step S25.

  That is, in this case, the control device 23 determines that the compressor temperature Ta exceeds the first circulation fan determination temperature T2 (= 95 ° C.) (YES in step S23) or the condenser temperature Sa determines the second circulation fan. If the temperature exceeds S2 (= 70 ° C.) (YES in step S26), it is determined that the temperature of the compressor 43 is high, and the process proceeds to step S24 to increase the rotational speed F of the circulation fan 36. On the other hand, in the control device 23, the compressor temperature Ta is equal to or lower than the first circulation fan determination temperature T2 (= 95 ° C.) (NO in step S23), and the condenser temperature Sa is equal to the second circulation fan determination temperature S2 (= 70 ° C.) or less (NO in step S26), it is determined that the temperature of the compressor 43 is low, the process proceeds to step S25, and the rotational speed F of the circulation fan 36 is set to the initial value F0.

  In this embodiment, steps S37 and S38 are added to the compressor stop determination of the first embodiment shown in FIG. 8 as shown in FIG. When the compressor temperature Ta does not exceed the first compressor stop temperature T1 (= 100 ° C.) in step S32 (NO), the control device 23 proceeds to step S37. If the condenser temperature Sa does not exceed the second compressor stop temperature S1 (NO in step S37), the control device 23 proceeds to step S12 shown in FIG. 6 (return). On the other hand, when the condenser temperature Sa exceeds the second compressor stop temperature S1 in step S37 (YES), the control device 23 proceeds to step S33.

  That is, in this case, the control device 23 determines that the compressor temperature Ta exceeds the first compressor stop temperature T1 (= 100 ° C.) (YES in step S32), or the condenser temperature Sa stops the second compressor. If the temperature exceeds S1 (YES in step S37), it is determined that the drive of the compressor 43 has exceeded the range of the normal temperature, the process proceeds to step S33, and the compressor 43 is temporarily stopped. On the other hand, the compressor temperature Ta does not exceed the first compressor stop temperature T1 (= 100 ° C.) (NO in step S32), and the condenser temperature Sa does not exceed the second compressor stop temperature S1. (NO in step S37), it is determined that the compressor 43 is stable within the normal temperature range.

  If the compressor temperature Ta is lower than the first compressor restart temperature T3 (= 95 ° C.) in step S35 (YES in step S35), the control device 23 proceeds to step S38. Then, the control device 23 determines that the cooling of the compressor 43 is sufficient when the condenser temperature Sa is lower than the second compressor restart temperature S3 (= 70 ° C.) (YES in step S38), The process proceeds to step S36 and the compressor 43 is restarted. On the other hand, when the compressor temperature Ta is equal to or higher than the first compressor restart temperature T3 (= 95 ° C.) (NO in step S35), the controller 23 determines that the condenser temperature Sa is the second compressor restart temperature. When it is S3 (= 70 ° C.) or higher (NO in step S38), it is determined that the cooling of the compressor 43 is insufficient, and the process proceeds to step S12 shown in FIG. 6 (return).

  That is, in this case, the control device 23 determines that the compressor temperature Ta is lower than the first compressor restart temperature T3 (= 95 ° C.) (YES in step S35) and the condenser temperature Sa is restarted. When the temperature is lower than S3 (= 70 ° C.) (YES in step S38), it is determined that the compressor 43 is sufficiently cooled, the process proceeds to step S36, and the compressor 43 is restarted. On the other hand, when the compressor temperature Ta is higher than the first compressor restart temperature T3 (= 95 ° C.) (NO in step S35), the control device 23 determines that the condenser temperature Sa is the second compressor restart. When the temperature is higher than S3 (= 70 ° C.) (NO in step S38), it is determined that the cooling of the compressor 43 is insufficient, and the process proceeds to step S12 shown in FIG.

  According to this, since the control device 23 determines the stop of the compressor 43 based on the temperatures at the two locations of the compressor 43 and the condenser 42, the temperature of the compressor 43 is increased, and consequently the temperature of the heat pump unit 40 is increased. Can be determined more accurately. As a result, the operation of the heat pump unit 40 can be made safer.

(Third embodiment)
Next, a third embodiment will be described with reference to FIGS.
In the third embodiment, the washing / drying machine 10 includes a cooling fan 60 for cooling the compressor 43, as shown in FIG. As shown in FIG. 12, the cooling fan 60 is connected to the control device 23 and driven and controlled by the control device 23.

  In the present embodiment, a cooling fan drive determination (step S16) is added to the control contents of the first embodiment shown in FIG. 6 as shown in FIG. In this case, the washing / drying machine 10 is preset with a cooling fan drive temperature H1 and a cooling fan stop temperature H2. The cooling fan drive temperature H1 is the temperature of the compressor 43 that is a criterion for starting the driving of the cooling fan 60. In the present embodiment, the cooling fan drive temperature H1 is set to 85 ° C., which is 20 ° C. lower than the compressor upper limit temperature T (= 105 ° C.). Is set. The cooling fan stop temperature H2 is the temperature of the compressor 43 that is a determination criterion for stopping the cooling fan 60. In this embodiment, the cooling fan stop temperature H2 is set to 75 ° C., which is 10 ° C. lower than the cooling fan drive temperature H1 (= 85 ° C.). Has been.

  In step S12, the control device 23 determines whether or not the drying process end condition is satisfied. If the drying process end condition is not satisfied (NO in step S12), the control device 23 proceeds to step S16. When the control device 23 proceeds to step S <b> 16, it executes a cooling fan drive determination. In the cooling fan drive determination, the control device 23 controls driving / stopping of the cooling fan 60 based on the compressor temperature Ta.

  When executing the cooling fan drive determination, the control device 23 first determines whether or not the cooling fan 60 is being driven in step S41 as shown in FIG. If the cooling fan 60 is not driven (NO in step S41), the control device 23 proceeds to step S42. When the compressor temperature Ta exceeds the cooling fan drive temperature H1 (= 85 ° C.) (YES in step S42), the control device 23 proceeds to step S43 and drives the cooling fan 60. Thereby, the temperature rise of the compressor 43 is suppressed. Thereafter, the control device 23 proceeds to step S13 in FIG. 13 (return). On the other hand, when the compressor temperature Ta does not exceed the cooling fan drive temperature H1 (= 85 ° C.) (NO in step S42), the control device 23 proceeds to step S13 in FIG. 13 without driving the cooling fan 60. (Return)

  If the cooling fan 60 is being driven (YES in step S41), the control device 23 proceeds to step S44. When the compressor temperature Ta is lower than the cooling fan stop temperature H2 (= 75 ° C.) (YES in step S44), the control device 23 determines that the temperature of the compressor 43 has sufficiently decreased and proceeds to step S45. . And the control apparatus 23 stops the cooling fan 60 in step S45, and transfers to step S13 of FIG. 13 after that (return). On the other hand, when the compressor temperature Ta is equal to or higher than the cooling fan stop temperature H2 (= 75 ° C.) (NO in step S44), the control device 23 continues cooling the compressor 43 by the cooling fan 60. Without stopping, the process proceeds to step S13 in FIG. 13 (return).

  According to this, the temperature rise of the compressor 43 can be more effectively suppressed by the air blowing action of the cooling fan 60. Therefore, the frequency which stops the compressor 43 in order to cool the compressor 43 is reduced, and, thereby, high safety can be ensured for the operation of the heat pump unit 40 while suppressing a decrease in drying efficiency. As a result, it is possible to provide a heat pump dryer that is safer and has a higher drying efficiency.

In addition, each said embodiment is not restricted to what was equipped with the washing function, The dryer which is not equipped with the washing function may be sufficient.
Further, the control device 23 is a temperature sensor other than the compressor temperature sensor 53 and the condenser temperature sensor 54, for example, an inlet temperature sensor 51, an exhaust port temperature sensor 52, an evaporator inlet temperature sensor 55, and an evaporator outlet temperature sensor 56. Even if a change in the temperature of the compressor 43 is indirectly detected based on the detected temperature such as, the compressor 43 is temporarily stopped, the rotational speed of the circulation fan 36 is increased or decreased, and the cooling fan 60 is driven. Good. The pressure adjusting means is not limited to the configuration of the bypass 46 and the first on-off valve 47 provided separately from the compressor 42, and may be one built in the compressor 42, for example.

  According to the configuration of the embodiment described above, the heat pump unit has the pressure difference adjusting means, the shut-off means, the check valve, and the control means. The pressure difference adjusting means balances the pressure difference between the suction side and the discharge side of the compressor while the compressor is stopped. The blocking means blocks the movement of the refrigerant from the condenser side to the evaporator side while the compressor is stopped. The check valve is provided between the evaporator and the compressor and prevents the refrigerant from flowing backward from the compressor side to the evaporator side. Then, the control device temporarily stops the compressor based on the temperature detected by the temperature detecting means during the drying process.

  According to this, a sufficient amount of refrigerant is present on the suction side of the compressor when the compressor is restarted after being temporarily stopped for cooling during the drying process. Therefore, the compressor can supply the refrigerant at a sufficient pressure from a relatively early stage after the restart. Therefore, the heat pump unit can be quickly started up after restarting, and as a result, safety can be improved while suppressing a decrease in drying efficiency.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and equivalents thereof.

  In the drawings, 10 is a washing dryer (heat pump dryer), 12 is a water tank (drying chamber), 13 is a rotating tank (drying chamber), 16 is an exhaust port, 17 is an air supply port, 23 is a control device, 30 is Circulating air passage, 40 is a heat pump unit, 41 is an evaporator, 42 is a condenser, 43 is a compressor, 431 is a suction side, 432 is a discharge side, 44 is a pressure reducing device, 46 is a bypass (pressure adjusting means), 47 Is a first on-off valve (pressure adjusting means), 48 is a second on-off valve (cut-off means), 49 is a check valve, 53 is a compressor temperature sensor (temperature detecting means), and 54 is a condenser temperature sensor (temperature detecting means). ), 60 indicates a cooling fan.

Claims (5)

A drying chamber having an exhaust port and an air supply port;
A circulation air passage provided outside the drying chamber and connecting the exhaust port and the air supply port;
A heat pump unit for dehumidifying and heating the air in the circulation air passage;
Temperature detecting means for detecting the temperature of the heat pump unit;
A controller for controlling the heat pump unit to perform a drying process,
The heat pump unit includes a condenser that is provided in the circulation air passage and heats the air in the circulation air passage, an evaporator that is provided in the circulation air passage and dehumidifies the air in the circulation air passage, A decompression device provided between the evaporator and the condenser, and a compressor that is provided outside the circulation air passage and that supplies the refrigerant are connected in a ring shape, and the compressor is stopped. Pressure difference adjusting means for balancing the pressure difference between the suction side and the discharge side of the compressor, and a blocking means for blocking the movement of the refrigerant from the condenser side to the evaporator side while the compressor is stopped. A check valve provided between the evaporator and the compressor to prevent a reverse flow of refrigerant from the compressor side to the evaporator side,
The said control apparatus is a heat pump type dryer which stops the said compressor temporarily based on the detected temperature of the said temperature detection means during the said drying process.   The heat pump dryer according to claim 1, further comprising a compressor temperature sensor that detects a temperature of the compressor as the temperature detecting means.   The heat pump dryer according to claim 2, further comprising a condenser temperature sensor that detects a temperature of the condenser as the temperature detecting means. A cooling fan that cools the compressor by blowing air to the compressor;
The said control apparatus is a heat pump type dryer as described in any one of Claim 1 to 3 which drives the said cooling fan based on the detected temperature of the said temperature detection means during the said drying process. The pressure adjusting means bypasses the compressor and connects a suction side and a discharge side of the compressor, and is provided in the middle of the bypass path and is opened and closed under the control of the control device. And an on-off valve,
The shut-off means is constituted by a second on-off valve provided between the condenser and the evaporator and opened and closed under the control of the control device,
In the drying process, the control device closes the first on-off valve and opens the second on-off valve while the compressor is being driven, and the temperature detecting means detects a temperature exceeding a predetermined temperature. The heat pump dryer according to any one of claims 1 to 4, wherein the compressor is temporarily stopped to open the first on-off valve and to close the second on-off valve.

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