JP2008000195A - Clothes dryer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a clothes dryer capable of appropriately detecting the close of a circulation air pathway and preventing the decline in the drying efficiency. <P>SOLUTION: If the circulation air pathway 36 is closed in the place where an evaporator 39 is disposed, air out of the circulation air pathway 36 flows into the circulation air pathway 36 from a second vent 48 disposed between the evaporator 39 and a condenser 40 in the circulation air pathway 36. A control device 11 controls a compressor 41 to stop the driving if the control device determines that the resistance inside the circulation air pathway 36 becomes large based on the temperature detected by a thermistor 49 for air between the evaporator and condenser disposed near the second vent 48. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a clothes dryer having a drying function using a heat pump.

In this type of clothes dryer, a circulation air passage communicating with a water tank is provided, and a condenser and an evaporator constituting a heat pump are disposed in the circulation air passage. And by circulating the air in a water tank and a circulation air path with a ventilation fan, the air (warm air) warmed with the condenser is supplied in a water tank, and the water of the laundry in a water tank is carried out with this hot air. Is being taken away. Thereafter, the air in the water tank is sent to an evaporator, and the water contained in the warm air is cooled and dehumidified in the evaporator (see, for example, Patent Document 1).
In addition, in a clothes dryer equipped with such a heat pump, it is considered to detect the temperature of the condenser that constitutes the heat pump and to control the driving of the heat pump based on this detected temperature (for example, Patent Documents). 2).
JP 2006-87484 A JP-A-2004-215543

  In the case where the laundry is dried by the heat pump as described above, when the temperature of the evaporator is lowered, the dehumidified water generated in the evaporator is frozen in the evaporator (particularly, the heat transfer fin portion that performs heat exchange). This may block the circulation air path. As a result, there is a problem that the air in the water tank and the circulation air passage cannot be circulated and the drying efficiency is deteriorated.

  Here, when the technique of Patent Document 2 described above is applied and the temperature of the evaporator, not the condenser, is detected, and the freezing of the dehumidified water is detected based on the temperature of the evaporator, the heat pump is driven. A configuration to control is conceivable. However, even if the temperature of the evaporator is detected, from this detected temperature, it can only be predicted that the dehumidified water has been frozen (the circulation air passage is blocked by this freezing). It is not possible to detect that the circulation air passage is blocked by freezing. As a result, there is a possibility that the drive of the heat pump may be controlled even though the circulation air passage is not actually blocked, and there is a problem that the drying efficiency is deteriorated.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to appropriately detect that the circulation air passage is blocked, and to prevent a decrease in drying efficiency. It is to provide a dryer.

  The clothes dryer according to claim 1 includes a rotating tub for storing clothes, a water tank for rotatably storing the rotating tank, a circulation air passage provided outside the water tank and communicating with the water tank, A blower fan provided in a circulation air passage for circulating air in the water tank and the circulation air passage, an evaporator disposed in the circulation air passage, and a downstream side of the evaporator in the circulation air passage A condenser disposed in the compressor, a compressor and a decompression means that constitute a heat pump together with the evaporator and the condenser, and the circulation air passage positioned between the evaporator and the condenser of the circulation air passage. A communication port provided so as to allow communication between the inside and the outside, air temperature detection means for detecting the temperature of the air between the evaporator and the condenser in the circulation air passage, and the compressor Control means for controlling drive, the control means Based on the detected temperature of the air temperature detecting means detects, when it is determined that the air passage resistance of the circulating air passage is increased, characterized in that control to stop the driving of the compressor.

  According to the clothes dryer of claim 1, when the air path resistance is increased by freezing or the like in the portion where the evaporator is disposed in the circulation air path, the air outside the circulation air path is changed into the evaporator and the condenser. Flows into the circulation air passage from the communication port provided between the two, and as a result, the detected temperature detected by the air temperature detecting means rises. At this time, the control means determines that the air path resistance in the circulation air path has increased based on the detected temperature detected by the air temperature detecting means, and controls to stop driving the compressor.

  Unless the airway resistance increases at the part where the evaporator is located in the circulation airway, the air outside the circulation airway will not flow into the circulation airway, which will block the circulation airway. It can be detected appropriately. In addition, the control means controls the compressor to stop driving only when the air path resistance is increased at the portion where the evaporator is disposed in the circulation air path, so that the circulation air path is blocked. In spite of the absence, the drive of the compressor does not stop, thereby preventing a decrease in drying efficiency.

(First embodiment)
Hereinafter, a first embodiment in which a clothes dryer of the present invention is applied to a washing dryer 1 will be described with reference to FIGS. 1 to 4.
As shown in FIG. 1, a water tank 3 and a drum 4 (corresponding to a rotating tank) are provided inside an outer box 2 of the washing / drying machine 1. Both the water tank 3 and the drum 4 are formed in a cylindrical shape whose rear surface is closed, and the axial direction thereof is disposed so as to be inclined forwardly with respect to the front-rear direction (left-right direction in FIG. 1). Yes. Moreover, the opening part 5 and the opening part 6 are provided in the front surface (left side in FIG. 1) of the water tank 3 and the drum 4, respectively. The opening 5 of the water tank 3 surrounds the opening 6 of the drum 4. Further, the opening 5 of the water tank 3 is watertightly connected to an opening 7 provided on the front surface of the outer box 2 by a bellows 8. The opening 7 can be opened and closed by a door 9, and the laundry can be taken in and out of the drum 4 by opening the door 9.

  A control unit 10 necessary for controlling the washing / drying machine 1 is provided in the upper part of the outer box 2. The control unit 10 is provided with a control device 11 (corresponding to control means, see FIG. 2), which will be described later. In addition, a water supply device 15 including a water supply valve 12, a water supply case 13, and a water supply hose 14 for supplying water into the water tank 3 is provided in an upper portion of the outer box 2.

  A hot air outlet 16 composed of a plurality of holes is provided in the upper part of the front surface of the water tank 3 (the part above the opening 5). A hot air inlet 17 is provided at the upper part of the rear surface of the water tank 3. A drain port 18 is provided at the bottom of the rear end side of the water tank 3. A drain valve 19 provided outside the water tank 3 is connected to the drain port 18, and further, a drain hose 20 is connected to the drain valve 19. Thereby, when the drain valve 19 is opened, the water in the water tank 3 is discharged outside the apparatus.

  The drum portion 4b of the drum 4 is provided with a number of holes 21 for dehydration and ventilation over substantially the entire area thereof. In addition, a plurality of (for example, about three) baffles 22 for stirring the laundry are provided on the inner peripheral surface of the body 4b of the drum 4. The baffles 22 are arranged at substantially equal intervals along the inner peripheral surface of the drum portion 4 b of the drum 4. In addition, a liquid-sealed rotary balancer 23 is provided at the edge of the front surface 4c of the drum 4, for example.

  A motor 24 is attached to the back surface 3 a of the water tank 3 in a state where the rotating shaft 24 a is inserted into the water tank 3. The center part of the rear surface 4a of the drum 4 is attached to the tip of the rotating shaft 24a. Thereby, the drum 4 is rotatably supported coaxially in the water tank 3. The water tank 3 is elastically supported in the outer box 2 by a plurality of suspensions 25 (only one is shown in FIG. 1). Further, in this case, the motor 24 is an outer rotor type thin brushless DC motor, and functions as a driving device for rotating the drum 4.

  A ventilation duct 27 is disposed below the water tank 3 (on the bottom surface of the outer box 2) via a base plate 26. An air intake port 28 is provided in the upper part on the front end side of the ventilation duct 27, and the air intake port 28 is connected to the hot air outlet 16 of the water tank 3 through a connection hose 29 and a return air duct 30. . On the other hand, a casing 32 of the blower 31 is connected to the rear end side of the ventilation duct 27, and the discharge port 33 of the casing 32 is connected to the hot air inlet 17 of the water tank 3 via the connection hose 34 and the air supply duct 35. It is connected to the. As a result, the circulation air passage 36 communicated from the hot air outlet 16 of the water tank 3 to the hot air inlet 17 through the return air duct 30, the connection hose 29, the ventilation duct 27, the casing 32, the connection hose 34 and the air supply duct 35. Is provided.

  Note that the above-described return air duct 30 is branched and piped to the left and right sides of the opening 5 on the front surface of the water tank 3, and joined at the lower part of the opening 5 and connected to the connection hose 29. The above-described air supply duct 35 is piped so as to bypass the left side of the motor 24 on the back surface of the water tank 3. The blower 31 described above includes a blower fan 37 that is provided inside the casing 32 and includes a centrifugal impeller, and a fan motor 38 that is provided outside the casing 32 and rotates the blower fan 37.

  An evaporator 39 is disposed inside the ventilation duct 27 in the circulation air passage 36. A condenser 40 is disposed inside the ventilation duct 27 on the downstream side (right side in FIG. 1) of the evaporator 39. Although neither the evaporator 39 nor the condenser 40 is shown in detail in detail, the refrigerant pipes 44 are arranged on a plurality of heat transfer fins at a fine pitch, and are excellent in heat exchange. The air circulating in the ventilation duct 27 passes between the heat transfer fins.

  The evaporator 39 and the condenser 40 constitute a heat pump 43 together with a compressor 41 and particularly an electronic throttle valve 42 (corresponding to a pressure reducing means, see FIG. 2). The heat pump 43 has a configuration (refrigeration cycle) in which a compressor 41, a condenser 40, a throttle valve 42, and an evaporator 39 are connected in a cycle by a refrigerant pipe 44. When the compressor 41 is driven, the refrigerant in the refrigerant pipe 44 circulates in the order of the compressor 41 → the condenser 40 → the throttle valve 42 → the evaporator 39.

  In this circulation process, the refrigerant in the refrigerant pipe 44 is compressed by the compressor 41 to become a high-temperature and high-pressure refrigerant and sent to the condenser 40. The high-temperature and high-pressure refrigerant sent to the condenser 40 dissipates heat by being condensed in the condenser 40. As a result, the air in the ventilation duct 27 is heated in the condenser 40, whereas the temperature of the refrigerant is lowered and liquefied. The liquefied refrigerant is decompressed when passing through the throttle valve 42 and sent to the evaporator 39. The refrigerant sent to the evaporator 39 absorbs heat by being vaporized in the evaporator 39. As a result, the air in the ventilation duct 27 is cooled and dehumidified in the evaporator 39. The refrigerant that has passed through the evaporator 39 is sent to the compressor 41 again.

  Further, when the fan motor 38 of the blower 31 is operated, the air in the water tank 3 (in the drum 4) and the circulation air passage 36 circulates as shown by solid line arrows in FIG. . In this circulation process, air (warm air) heated by the condenser 40 is blown into the water tank 3 from the hot air inlet 17 through the connection hose 34 and the air supply duct 35, and this warm air causes The moisture of the laundry in the drum 4 is taken away. Thereafter, the air in the water tank 3 (air containing moisture) is blown out from the hot air outlet 16 through the return air duct 30 and the connection hose 29 to the evaporator 39, and in this evaporator 39, the water contained in the hot air Is cooled and dehumidified. The air dehumidified by the evaporator 39 is sent to the condenser 40 and heated again, and then blown into the water tank 3. Thus, the evaporator 39 functions as a dehumidifier, and the condenser 40 functions as a heater.

  A plurality of hot air inlets 45 are provided on the back surface 4 a of the drum 4. The plurality of hot air inlets 45 are concentrically arranged on the rear surface 4a of the drum 4 with the rotation shaft 24a of the motor 24 as the central axis. Therefore, each hot air introduction port 45 sequentially faces the hot air inlet 17 of the water tank 3 as the drum 4 rotates. Accordingly, the hot air supplied from the hot air inlet 17 into the water tank 3 is supplied into the drum 4 from the hot air inlet 45 facing the hot air inlet 17 at that time.

  A first communication port 46 is provided on the upper surface of the ventilation duct 27 on the upstream side (left side in FIG. 1) of the evaporator 39 so as to communicate the inside and the outside of the ventilation duct 27. Inside the ventilation duct 27, a portion between the first communication port 46 and the evaporator 39 is provided with a blown air thermistor 47 that detects the temperature of the air blown from the drum 4 (water tank 3). It has been.

  A second communication port 48 is provided on the upper surface of the ventilation duct 27 between the evaporator 39 and the condenser 40 so as to communicate the inside and the outside of the ventilation duct 27. In the ventilation duct 27, the portion between the second communication port 48 and the condenser 40 is an evaporation that detects the temperature of the air between the evaporator 39 and the condenser 40 in the ventilation duct 27. A thermistor 49 for air between the condenser and the condenser (corresponding to air temperature detecting means) is provided. The blown air thermistor 47 and the evaporator / condenser air thermistor 49 are covered by cylindrical covers (not shown) having slits on the upstream side and the downstream side, respectively.

  The evaporator 39 is provided with an evaporator thermistor 50 (corresponding to an evaporator temperature detecting means) that detects the temperature of the evaporator 39. Further, the condenser 40 is provided with a condenser thermistor 51 (condenser temperature detecting means) for detecting the temperature of the condenser 40. Inside the air supply duct 35, in the vicinity of the hot air inlet 17 of the water tank 3, a blown air thermistor 52 that detects the temperature of the air blown into the drum 4 (water tank 3) is provided. In addition, inside the outer box 2 of the washing / drying machine 1, an outside air thermistor 53 (corresponding to outside air temperature detecting means) that detects the temperature of the air outside the ventilation duct 27 is provided on the front end side of the ventilation duct 27. ing.

  FIG. 2 is a block diagram schematically showing the electrical configuration of the washing / drying machine 1. The control device 11 described above is configured mainly with a microcomputer, and controls the overall operation of the washing / drying machine 1. An operation input unit 54, a water level sensor 55, and a rotation sensor 56 are connected to the control device 11. Further, the control device 11 is connected to the blown air thermistor 47, the evaporator / condenser air thermistor 49, the evaporator thermistor 50, the condenser thermistor 51, the blown air thermistor 52, and the outside air thermistor 53. ing.

  The operation input unit 54 inputs various operation signals from various operation switches (not shown) of the operation panel to the control device 11. The water level sensor 55 inputs the detected water level in the water tank 3 to the control device 11 as a water level detection signal. The rotation sensor 56 is provided in the motor 24, and inputs the detected rotation of the motor 24 and thus rotation of the drum 4 to the control device 11 as a rotation detection signal. Each thermistor 47, 49, 50, 51, 52, 53 inputs the detected temperature to the control device 11 as a temperature detection signal. The control device 11 drives the water supply valve 12, the motor 24, the drain valve 19, the compressor 41, the throttle valve 42, and the fan motor 38 based on various input signals and a previously stored control program. 57 is controlled.

Next, the effect | action of 1st Embodiment is demonstrated with reference to FIG.3 and FIG.4.
FIG. 3 is a diagram showing an aspect of a general change in the detected temperature detected by each thermistor when a drying operation is performed with the washing / drying machine 1 having the above-described configuration.
In this case, at the start of the drying operation, the temperature Ta of the evaporator 39 (corresponding to the detected temperature detected by the evaporator temperature detecting means), the temperature Tb of the condenser 40 (corresponding to the detected temperature detected by the condenser temperature detecting means) The temperature Tc of the air between the evaporator and the condenser (corresponding to the detected temperature detected by the air temperature detecting means), the temperature Td of the air blown into the drum 4 and the temperature Te of the air blown from the drum 4 are It matches the temperature Tf (corresponding to the detected temperature detected by the outside air temperature detecting means). When the drying operation is started from this state, the temperature Ta of the evaporator 39 is lowered to a constant temperature t1 by the action of the heat pump 43 and stabilized as the operation time of the drying operation elapses. In this case, the temperature Ta of the evaporator 39 is once lowered to a low temperature by the supercooling of the heat pump 43 immediately after the drying operation. On the other hand, the temperature Tb of the condenser 40 rises to a constant temperature t2 by the action of the heat pump 43 and is stabilized.

  The temperature Tc of the air between the evaporator and the condenser decreases to a certain temperature t3 as the temperature Ta of the evaporator 39 decreases because the air cooled by the evaporator 39 is sent to the part. Stabilize. Since the temperature (Td) of the air blown into the drum 4 is supplied with air (warm air) heated by the condenser 40, the temperature Td reaches a certain temperature t4 as the temperature Tb of the condenser 40 increases. Ascend and stabilize. The temperature Te of the air blown from the drum 4 is that the warm air contains the moisture of the laundry in the drum 4, so that the operation time of the drying operation has elapsed (drying of the laundry has progressed). As the amount of water contained in the hot air decreases, it gradually increases.

  The above-described temperature Tb of the condenser 40 detects the temperature of a part of the condenser 40 (the part where the condenser thermistor 51 is disposed). On the other hand, the temperature Td of the air blown into the drum 4 detects the temperature of the air heated by the entire condenser 40. Therefore, the temperature Td of the air blown into the drum 4 becomes higher than the temperature Tb of the condenser 40 throughout the drying operation.

  By the way, during the above-described drying operation, the dehumidified water generated in the evaporator 39 may freeze in the evaporator 39 and block the circulation air passage 36. Here, the operation when the circulation air passage 36 is blocked in the portion where the evaporator 39 is disposed will be described with reference to FIG.

  When the dehumidified water begins to freeze in the evaporator 39 during the drying operation (indicated by a white arrow [freeze] in FIG. 4), the air path is generated by freezing in the portion where the evaporator 39 is disposed in the circulation air path 36. Resistance increases. Therefore, a part of the air blown out from the drum 4 flows out of the circulation air passage 36 from the first communication port 46 on the upstream side of the evaporator 39 (indicated by a broken arrow A in FIG. 1). On the other hand, the air outside the circulation air passage 36 flows into the circulation air passage 36 from the second communication port 48 (indicated by a broken line arrow B in FIG. 1). In this state, the temperature Tc of the air between the evaporator and the condenser gradually increases due to the air outside the circulation air passage 36 that has flowed in from the second communication port 48.

  When the temperature Tc of the air between the evaporator and the condenser continues to rise gradually and reaches a preset threshold value P, the control device 11 increases the air path resistance in the circulation air path 36. And control to stop the driving of the compressor 41 (indicated by a white arrow [compressor stop] in FIG. 4). Further, the control device 11 operates the fan motor 38 of the blower 31 to circulate the air in the water tank 3 and the circulation air passage 36 even after controlling the compressor 41 to stop driving.

When the driving of the compressor 41 is stopped, the circulation of the refrigerant in the heat pump 43 is stopped, and the high-temperature refrigerant and the low-temperature refrigerant are mixed in the refrigerant pipe 44. For this reason, the temperature Ta of the evaporator 39 gradually increases, whereby the freezing in the evaporator 39 is gradually eliminated. On the other hand, since the temperature Tb of the condenser 40 decreases, the difference between the temperature Ta of the evaporator 39 and the temperature Tb of the condenser 40 gradually decreases.
After that, when the difference between the temperature Ta of the evaporator 39 and the temperature Tb of the condenser 40 (difference indicated by an arrow C in FIG. 4) becomes, for example, 10 ° C. or less as a predetermined value for restart, the control device 11 It is determined that the air path resistance in the circulation air path 36 has become smaller (freezing in the evaporator 39 has been eliminated), and control is performed so that the drive of the compressor 41 is restarted (restarted in FIG. 4). (Shown with a pull-out arrow [restart compressor]).

  When the driving of the compressor 41 is resumed, the refrigerant circulation of the heat pump 43 is started again, so that the temperature Ta of the evaporator 39 gradually decreases, while the temperature Tb of the condenser 40 gradually increases. To do. Further, in the state where the freezing in the evaporator 39 has been eliminated, the air outside the circulation air passage 36 does not flow into the circulation air passage 36 from the second communication port 48, and the water in the water tank 3 and the circulation Since the air in the air passage 36 is appropriately circulated through the evaporator 39 and the condenser 40, the temperature Tc of the air between the evaporator and the condenser gradually decreases, and the temperature Td of the air blown into the drum 4 And the temperature Te of the air blown out from the drum 4 gradually rises.

  As described above, according to the first embodiment, the second communication port 48 for communicating the inside and the outside of the circulation air passage 36 is provided between the evaporator 39 and the condenser 40 in the circulation air passage 36. Since the air path resistance does not increase at the portion where the evaporator 39 is disposed in the circulation air passage 36, the air outside the circulation air passage 36 does not flow into the circulation air passage 36. Accordingly, it is possible to appropriately detect that the circulation air passage 36 is blocked. Further, the control device 11 performs control so as to stop the driving of the compressor 41 only when the air path resistance is increased at the portion in the circulation air path 36 where the evaporator 39 is disposed. However, the compressor 41 does not stop driving even though it is not blocked, thereby preventing a decrease in drying efficiency.

  Further, when the driving of the compressor 41 is stopped, the difference between the temperature Ta of the evaporator 39 and the temperature Tb of the condenser 40 is gradually reduced, and the evaporator 39 is increased as the temperature of the evaporator 39 increases. The freezing at will gradually disappear. When the controller 11 determines that the difference between the temperature Ta of the evaporator 39 and the temperature Tb of the condenser 40 has become equal to or less than a predetermined value (freezing in the evaporator 39 has been eliminated), the control device 11 drives the compressor 41. Control to resume. Thereby, although the freezing in the evaporator 39 is eliminated, the drying action by the heat pump 43 is not stopped, and the drying efficiency can be improved.

The above-described threshold value P is not limited to a constant value, and is appropriately changed based on the temperature Tc of the air between the evaporator and the condenser, the temperature Ta of the evaporator 39, and the temperature Tf of the outside air. Can be set. For example, the difference between the temperature Tf of the outside air and the temperature Ta of the evaporator 39 can be set as 100%, and a temperature of 50% can be set as the threshold value P.
Further, the air path resistance in the circulation air path 36 is not only increased by freezing in the evaporator 39, but also lint contained in the air in the water tank 3 and the circulation air path 36 is evaporated. It is also enlarged by accumulating in 39. Even in this case, if the air path resistance increases at the portion where the evaporator 39 is disposed in the circulation air path 36, the air outside the circulation air path 36 flows from the second communication port 48 to the circulation air path 36. Therefore, it is possible to appropriately detect not only that the circulation air passage 36 is blocked by freezing but also that it is blocked by yarn waste.

(Second Embodiment)
Next, a second embodiment in which the clothes dryer of the present invention is applied to the washing dryer 1 will be described with reference to FIG. The second embodiment is different from the first embodiment in the method of determining that the air path resistance in the circulation air path 36 has increased. Hereinafter, description of the same parts as those described in the first embodiment will be omitted, and only different parts will be described.
When the dehumidified water begins to freeze in the evaporator 39 during the drying operation (indicated by a white arrow [freeze] in FIG. 5), the circulation air passage 36 is similar to that described in the first embodiment. External air flows into the circulation air passage 36 from the second communication port 48, and the temperature Tc of the air between the evaporator and the condenser gradually increases.

During the drying operation, the control device 11 calculates the amount of change in the air temperature Tc between the evaporator and the condenser (the rate of change in the air temperature Tc between the evaporator and the condenser) every minute as a predetermined time. . If the amount of change exceeding 1 ° C. (the amount of change in temperature indicated by points D, E, and F in FIG. 5) is obtained three times in succession as a result of the calculation, It is determined that the road resistance has increased, and control is performed to stop the drive of the compressor 41 (indicated by a white arrow [compressor stop] in FIG. 5).
After that, the controller 11 restarts the difference between the temperature Ta of the evaporator 39 and the temperature Tb of the condenser 40 (the difference indicated by the arrow C in FIG. 5), similar to that described in the first embodiment. When the predetermined value is 10 ° C. or less, it is determined that the air path resistance in the circulation air path 36 has decreased (freezing in the evaporator 39 has been eliminated), and the driving of the compressor 41 is restarted (restart). (Indicated by a white arrow [restart the compressor] in FIG. 5).

  As described above, according to the second embodiment, the control device 11 determines the air path in the circulation air path 36 based on the calculation result of the amount of change in the air temperature Tc between the evaporator and the condenser. It can be determined whether or not the resistance has increased, and accordingly, it is possible to appropriately detect that the circulation air passage 36 is blocked.

(Third embodiment)
Next, a third embodiment in which the clothes dryer of the present invention is applied to the washing dryer 1 will be described with reference to FIG. The third embodiment also differs in the method for determining that the air path resistance in the circulation air path 36 has increased compared to the first embodiment described above. Hereinafter, description of the same parts as those described in the first embodiment will be omitted, and only different parts will be described.
When the dehumidified water starts to freeze in the evaporator 39 during the drying operation (indicated by a white arrow [freeze] in FIG. 6), the circulation air passage 36 is similar to that described in the first embodiment. External air flows into the circulation air passage 36 from the second communication port 48, and the temperature Tc of the air between the evaporator and the condenser gradually increases. In addition, since the dehumidified water is frozen in the evaporator 39, the temperature Ta of the evaporator 39 gradually decreases.

  Then, the temperature Tc of the air between the evaporator and the condenser continues to gradually increase and the temperature Ta of the evaporator 39 continues to decrease gradually, and the temperature Tc of the air between the evaporator and the condenser 39 When the difference from the temperature Ta (indicated by an arrow G in FIG. 6) is equal to or greater than the predetermined value for stopping, the control device 11 determines that the air path resistance in the circulation air path 36 has increased, and the compressor 41 Is controlled to be stopped (indicated by a white arrow [compressor stop] in FIG. 6).

  Note that the predetermined value for stopping is set based on the temperature Tf of the outside air as shown in FIG. In this case, as the temperature Tf of the outside air is lower, the evaporator 39 is more likely to freeze. Therefore, when the temperature Tf of the outside air is less than 5 ° C., the predetermined value for stopping is set to 5 ° C. When the temperature Tf is 5 ° C. to 20 ° C., the predetermined value for stopping is set to 7 ° C. If the outside air temperature Tf is high, freezing in the evaporator 39 hardly occurs. Therefore, when the outside air temperature Tf exceeds 20 ° C., the temperature Tc between the evaporator-condenser air and the evaporator 39 The temperature Ta is set so as not to determine whether or not the difference from the temperature Ta is equal to or less than a predetermined value for stopping.

  As described above, according to the third embodiment, the control device 11 determines that the inside of the circulation air passage 36 is based on the difference between the temperature Tc of the air between the evaporator and the condenser and the temperature Ta of the evaporator 39. It is possible to determine whether or not the airflow resistance has increased, and accordingly, it is possible to appropriately detect that the circulation airflow path 36 is blocked.

(Other embodiments)
In addition, this invention is not limited to each above-mentioned embodiment, It can deform | transform or expand as follows.

  In the second embodiment, the predetermined time interval for the controller 11 to calculate the amount of change in the temperature Tc of the air between the evaporator and the condenser is not limited to 1 minute, and the predetermined time is appropriately changed. Can be set. Further, the condition that the control device 11 determines that the air path resistance in the circulation air path 36 has increased from the calculation result is not limited to the case where the amount of change exceeding 1 ° C. is obtained three times in succession. The conditions can be changed and set as appropriate.

In the third embodiment, the predetermined value for stopping shown in FIG. 7 can be appropriately changed and set according to the temperature Tf of the outside air.
The timing at which the control device 11 resumes (restarts) driving of the compressor 41 is when the difference between the temperature Ta of the evaporator 39 and the temperature Tb of the condenser 40 is 10 ° C. or less as a predetermined value for restart. The predetermined value for restarting can be changed and set as appropriate.
In each of the above-described embodiments, the washing / drying machine 1 in which the axial direction of the water tank 3 is horizontal is illustrated, but the clothes dryer of the present invention can be applied to a washing / drying machine in which the axial direction of the water tank 3 is vertical. it can.

BRIEF DESCRIPTION OF THE DRAWINGS The 1st Embodiment of this invention is shown, The vertical side view which shows roughly the internal structure of a washing-drying machine Block diagram showing the electrical configuration of the washing and drying machine The figure which shows the relationship between the operation time of drying operation and the detected temperature which each thermistor detects The figure for demonstrating the effect | action of 1st Embodiment. FIG. 4 equivalent view showing the second embodiment of the present invention FIG. 4 equivalent view showing the third embodiment of the present invention The figure which shows the relationship between the temperature of outside air, and the predetermined value for a stop

Explanation of symbols

  In the drawing, 3 is a water tank, 4 is a drum (rotary tank), 11 is a control device (control means), 36 is a circulation air passage, 37 is a blower fan, 39 is an evaporator, 40 is a condenser, 41 is a compressor, 42 is a throttle valve (pressure reducing means), 43 is a heat pump, 48 is a second communication port (communication port), 49 is a thermistor for air between the evaporator and condenser (air temperature detecting means), and 50 is a thermistor for evaporator (evaporation). (Condenser temperature detecting means), 51 is a thermistor for condenser (condenser temperature detecting means), and 53 is a thermistor for outside air (outside air temperature detecting means).

Claims (4)

A rotating tub for storing clothing;
A water tank that rotatably accommodates the rotating tank;
A circulation air passage provided outside the water tank and communicating with the water tank;
A blower fan provided in the circulation air passage to circulate the air in the water tank and the circulation air passage;
An evaporator disposed in the circulation air passage;
A condenser disposed downstream of the evaporator in the circulation air passage;
A compressor and a decompression means constituting a heat pump together with the evaporator and the condenser;
A communication port provided between the evaporator and the condenser of the circulation air passage so as to communicate the inside and the outside of the circulation air passage;
Air temperature detecting means for detecting the temperature of air between the evaporator and the condenser in the circulation air path;
Control means for controlling the drive of the compressor,
The control means includes
A garment that controls to stop driving of the compressor when it is determined that the air path resistance in the circulating air path has increased based on the detected temperature detected by the air temperature detecting means. Dryer. Comprising an evaporator temperature detecting means for detecting the temperature of the evaporator;
The control means includes
Controlling the compressor to stop driving when it is determined that the difference between the detected temperature detected by the air temperature detecting means and the detected temperature detected by the evaporator temperature detecting means exceeds a predetermined value. The clothes dryer according to claim 1, wherein the clothes dryer is provided. Evaporator temperature detecting means for detecting the temperature of the evaporator;
A condenser temperature detecting means for detecting the temperature of the condenser;
The control means includes
When it is determined that the difference between the detected temperature detected by the evaporator temperature detecting means and the detected temperature detected by the condenser temperature detecting means has become a predetermined value or less, control is performed so as to restart the driving of the compressor. The clothes dryer according to claim 1. Evaporator temperature detecting means for detecting the temperature of the evaporator;
An outside air temperature detecting means for detecting the temperature of the air outside the circulation air passage;
The control means includes
Based on the detected temperature detected by the air temperature detecting means, the detected temperature detected by the evaporator temperature detecting means, and the detected temperature detected by the outside air temperature detecting means, the driving of the compressor is controlled to be stopped. The clothes dryer according to claim 1.

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