JPH11235499A - Clothes drier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a clothes drier which enables good drying operation without infinitely continuing temperature control. SOLUTION: A thermostat switches off during a drying operation by temperature control, and then, if the thermostat remains off for ten seconds, a thermostat-off counter for counting the number of times that the thermostat switches off from on is incremented to '1' (a step S25). After that, a state of the thermostat is repeatedly checked until the thermostat-off counter becomes '2', or it is determined in a step S11 that the drying operation by temperature control is completed. When the switching of thermostat from on to off is re- detected, and after that, the thermostat is off for ten seconds, the thermostat-off counter is incremented to '2', and the drying operation by temperature control is completed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clothes dryer for drying clothes in a rotating drum by flowing hot air through the rotating drum.

[0002]

2. Description of the Related Art Conventionally, a rotary drum for storing clothes, a fan for forming an air flow in the rotary drum, and a heater for heating air supplied to the rotary drum have been provided. 2. Description of the Related Art There is known a clothes dryer that dries clothes in a rotating drum by driving a fan and a heater to flow hot air through the rotating drum.

[0003] In this type of clothes dryer, a drum outlet temperature sensor for detecting the temperature of air immediately after passing through a rotating drum, and a control board on which a microcomputer or the like is mounted as a control center are mounted. And a substrate temperature sensor for detecting the temperature of the clothes. A drying operation for drying the clothes is executed based on the outputs of these two temperature sensors.

For example, on / off of a heater is controlled based on an output of a drum outlet temperature sensor. Specifically, the heater is turned off when the temperature detected by the drum outlet temperature sensor is equal to or higher than a predetermined upper limit temperature, and the heater is turned on when the temperature detected by the drum outlet temperature sensor is equal to or lower than the predetermined lower limit temperature. Thus, the temperature of the hot air flowing through the rotating drum can be kept substantially constant. The end of the drying operation is determined based on whether or not the temperature difference between the temperature detected by the drum outlet temperature sensor and the temperature detected by the substrate temperature sensor has reached a predetermined temperature difference or more.
That is, when the temperature difference between the two temperature sensors becomes equal to or more than the predetermined temperature difference, it is determined that the clothes in the rotating drum have been dried to the predetermined drying state, and the drying operation ends.

By the way, a lint filter for capturing lint and the like contained in air exhausted from the inside of the rotating drum is mounted on an exhaust port of the rotating drum. This lint filter is designed to prevent clogging due to lint, etc.
The user needs to clean it regularly. However,
In reality, cleaning is often not performed for a long time, and the lint filter may be used in a clogged state.

If the drying operation is performed in a state where the lint filter is clogged, the exhaust from the rotating drum cannot be performed well, so that the air in the rotating drum stays in spite of the driving of the fan. . As a result, the high-temperature air created by heating the heater may stay near the heater, and the vicinity of the heater may become hot. However, since the temperature detected by the drum outlet temperature sensor remains low, energization of the heater is continued, and the vicinity of the heater is further heated to a high temperature.

Therefore, a conventional clothes dryer is provided with a current sensor such as a current transformer for detecting the amount of current flowing through the heater in order to detect clogging of the lint filter. When the heater is constituted by a semiconductor heater, when the lint filter is clogged and the ambient temperature of the heater increases, the amount of current flowing through the heater decreases. Clogging of the filter can be detected. This can prevent the vicinity of the heater from becoming high temperature.

[0008]

However, since current sensors such as current transformers are relatively expensive, there is a problem that the cost of the clothes dryer is increased by providing the current sensors. Therefore, the inventor of the present application
It is considered that a thermostat is provided in a power supply circuit to the heater instead of the current sensor, and the thermostat is installed near the heater. Thus, when the ambient temperature of the heater becomes equal to or higher than a certain temperature, the power supply to the heater is cut off, so that even if the lint filter is clogged, it is possible to prevent the vicinity of the heater from becoming high temperature. In addition, since the thermostat is cheaper than the current sensor, the product cost can be reduced.

However, if a thermostat is provided in the power supply circuit to the heater, the drying operation may not be performed well. For example, if the temperature near the heater becomes high temperature during the drying operation and the thermostat is turned off, the thermostat is repeatedly turned on / off thereafter, and the temperature of the air exhausted from the rotating drum does not rise.
There is a possibility that the temperature difference between the two temperature sensors does not exceed the predetermined temperature difference and the drying operation is not completed.

[0010] When the operation is performed by setting the drying operation time, if the thermostat is repeatedly turned on / off, the total amount of heat supplied to the rotating drum during the drying operation is reduced. Water may not be completely removed. Furthermore, if the above current sensor is omitted, clogging of the lint filter cannot be detected, so that it is not possible to notify that the lint filter is clogged and to urge the user to clean the lint filter. .

SUMMARY OF THE INVENTION It is an object of the present invention to provide a clothes dryer capable of performing a drying operation satisfactorily even if a thermostat is provided in a power supply circuit of a heater.
Another object of the present invention is to provide a clothes dryer capable of detecting clogging of a filter without additionally providing a new component such as the current sensor.

[0012]

According to a first aspect of the present invention, there is provided a rotary drum for storing clothes to be dried, and a rotary drum for forming an air flow in the rotary drum. A blower, a heater for heating the air fed into the rotary drum by the blower, and a power supply circuit for the heater, wherein the power supply to the heater is cut off based on the ambient temperature around the heater.
A conducting thermostat, state detecting means for detecting whether the thermostat is in a cutoff state or a conducting state, and the thermostat by the state detecting means during a drying operation performed by driving the heater and the blower; And an operation control means for terminating the drying operation based on detection of a switch from the conduction state to the interruption state.

[0013] According to this configuration, the drying operation for drying the clothes in the rotating drum is terminated based on the detection of the switching of the thermostat from the conductive state to the cutoff state during the operation. Thus, for example, a first temperature sensor for detecting the temperature of the air exhausted from the rotating drum and a second temperature sensor for detecting the temperature of a place where the influence of the heat generated by the heater has been eliminated are provided. A change in the exhaust temperature of the rotating drum accompanying the progress of the drying operation is detected, such as terminating the drying operation based on the difference between the temperatures detected by the two temperature sensors being equal to or greater than a predetermined end reference value. Therefore, in the clothes dryer configured to determine the end of the drying operation, there is no inconvenience that the drying operation does not end because the exhaust temperature from the rotating drum does not rise due to the on / off of the heater by the thermostat.

According to a second aspect of the present invention, there is provided a rotary drum for storing clothes to be dried, a blower for forming an air flow in the rotary drum, and air blown into the rotary drum by the blower. A heater for heating the heater, a thermostat provided in a power supply circuit to the heater, for interrupting / conducting power to the heater based on an ambient temperature around the heater, and a thermostat for disconnecting or conducting the thermostat. A state detection unit for detecting whether the state is a state, and a switch from the conductive state to the cut-off state of the thermostat is detected by the state detection unit during a drying operation performed by driving the heater and the blower. And a time extending means for extending the time to execute the drying operation by a predetermined time based on the A dryer.

According to this configuration, the time for performing the drying operation is extended by the predetermined time based on the detection that the thermostat has been switched from the conductive state to the cutoff state during the drying operation. Thus, the total amount of heat supplied to the rotary drum during the drying operation can be made substantially the same when the heater is turned on / off by the thermostat and when the heater is not turned on / off.

That is, when the heater is repeatedly turned on / off by the thermostat when the drying operation is performed for a certain period of time, the total amount of heat supplied to the rotating drum within the certain period of time decreases. Therefore, by extending the time of the drying operation and supplementing the reduced amount of heat, the total amount of heat supplied to the rotating drum during the drying operation can be kept constant. Therefore, the clothes can be dried well regardless of whether the heater is turned on / off by the thermostat.

The invention according to claim 3 is based on the fact that, during the drying operation performed by driving the heater and the blower, switching of the thermostat from the conductive state to the cutoff state is detected by the state detecting means. hand,
3. The heater according to claim 1, further comprising heater control means for controlling the heater so as to reduce the amount of heat supplied to the rotary drum per predetermined time.
3. The clothes dryer according to item 1.

According to this configuration, based on the detection of the switching of the thermostat from the conductive state to the cutoff state, the thermostat is dried in a state in which the amount of heat supplied to the rotary drum per predetermined time is reduced. Driving is performed. As a result, the number of times the state of the thermostat switches during the subsequent drying operation is reduced, and the life of the thermostat can be extended.

According to a fourth aspect of the present invention, the heater includes a plurality of heating elements, and the output can be changed by selectively turning on / off the plurality of heating elements. Wherein the heater control means reduces the output of the heater in response to the state detection means detecting a predetermined number of times of switching of the thermostat from the conductive state to the cutoff state. A clothes dryer according to claim 3, wherein

According to this configuration, after the switching of the thermostat from the conductive state to the cut-off state is detected a predetermined number of times, the drying operation is performed with the output of the heater lowered. As a result, since the change in the ambient temperature around the heater becomes gentle, the number of times the state of the thermostat switches during the subsequent drying operation is reduced, and the life of the thermostat can be extended.

The invention according to claim 5 further includes a first temperature sensor for detecting the temperature of the air exhausted from the rotary drum, and the heater control means determines whether the temperature detected by the first temperature sensor is predetermined. Means for turning off the heater when the temperature becomes equal to or higher than a predetermined high limiter temperature, and thereafter turning on the heater when the temperature detected by the first temperature sensor becomes equal to or lower than a predetermined low limiter temperature. 4. The clothes dryer according to claim 3, further comprising: high limiter temperature changing means for lowering the high limiter temperature by a predetermined temperature in response to the detection of the switching to the cutoff state.

According to this configuration, when the switching of the thermostat from the conductive state to the cutoff state is detected during the drying operation, the high limiter temperature is lowered by a predetermined temperature. Thus, during the subsequent drying operation, the heater is turned off by the heater control means before the thermostat is switched from the conductive state to the cutoff state, so that the number of times the thermostat is switched can be reduced. Therefore, the life of the thermostat can be extended.

According to a sixth aspect of the present invention, there is provided a rotary drum for storing clothes to be dried, a blower for forming an air flow in the rotary drum, and air blown into the rotary drum by the blower. A filter for removing foreign substances contained in air exhausted from the rotating drum, and a heater mounted on an exhaust port formed in the rotating drum, and a heater exhausted from the rotating drum. A first temperature sensor for detecting the temperature of the air, a second temperature sensor for detecting the temperature of a place where the influence of the heat generated by the heater is eliminated, and a temperature detected by the first temperature sensor. Temperature determining means for calculating a difference from the temperature detected by the second temperature sensor and determining whether the calculated detected temperature difference is equal to or less than a predetermined determination reference value The filter is clogged based on the fact that the temperature difference between the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor is determined to be equal to or smaller than a reference value. And a clogging detecting means for detecting the presence of the clothes.

According to this configuration, it is possible to detect clogging of the filter mounted on the exhaust port of the rotating drum based on the temperatures detected by the first temperature sensor and the second temperature sensor. Therefore, it is not necessary to separately provide a current sensor or the like for detecting the amount of current flowing through the heater in order to detect clogging of the filter, so that the cost of the clothes dryer can be reduced.

According to a seventh aspect of the present invention, in the clogging detecting means, the temperature difference between the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor by the temperature determining means is equal to or smaller than a reference value. 7. The clothes dryer according to claim 6, wherein the filter is determined to be clogged when the state determined to be present continues for a predetermined time.

According to this configuration, the state where the temperature difference between the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor is equal to or smaller than the determination reference value is temporary due to, for example, the influence of noise or the like. Nevertheless, the risk of erroneously determining that the filter is clogged can be eliminated. Thereby, the detection accuracy of filter clogging can be improved.

According to an eighth aspect of the present invention, the heater has a plurality of heating elements, and the output can be changed by selectively turning on / off the plurality of heating elements. 8. The clothes dryer according to claim 6, further comprising a heater output control unit that reduces an output of the heater when the clogging detection unit detects that the filter is clogged. 9. It is.

According to this configuration, when it is determined that the filter is clogged, the drying operation is performed with the output of the heater lowered thereafter. Thereby, even when the filter is clogged, it is possible to avoid an abnormally high temperature around the heater,
There is no danger of heat damage to the clothes in the rotating drum.

In addition, when a thermostat for preventing an abnormally high temperature state around the heater is provided, a change in the ambient temperature around the heater becomes gentle due to a decrease in the output of the heater. The number of times the state of the thermostat switches during the drying operation can be reduced, and the life of the thermostat can be extended.

The reference value for determining whether the filter is clogged is preferably changed according to the temperature detected by the second temperature sensor and the output of the heater. That is, when the temperature detected by the second temperature sensor is low or when the heater output is large, the temperature difference between the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor is relatively large. Is preferably set to a relatively large value. On the other hand, when the temperature detected by the second temperature sensor is high or when the heater output is small, the temperature difference between the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor is relatively small. Is preferably set to a relatively small value. Thus, the clogged state of the filter can be detected more accurately.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described in detail with reference to the accompanying drawings. FIG. 1 is a sectional view showing a schematic configuration of a clothes dryer according to an embodiment of the present invention. The clothes dryer includes a housing 1 having an opening 1a on the front surface, a rotating drum 2 provided in the housing 1, and an openable / closable door 3 attached to the opening 1a of the housing 1. Clothes to be dried are put into the rotating drum 2 through the opening 1a of the housing 1 with the door 3 opened. On the front surface of the housing 1 and below the door 3, there is provided a panel case 4 in which an operation panel 40 including various push switches and indicators is arranged on the front surface. A control board 5 is provided inside the panel case 4. On the control board 5, a microcomputer described later and a board thermistor L for detecting a temperature on the control board 5 (hereinafter, referred to as "board temperature") are mounted.

The rotating drum 2 is provided with its end face in front and back. The front side is rotatably supported by a drum support plate 6 attached so as to surround the opening 1 a of the housing 1, and the rear side is the rear face of the housing 1. Is rotatably supported by a support shaft 7 inserted through the support shaft 7. An exhaust port 8 for exhausting the air in the rotary drum 2 is formed on the rear surface of the rotary drum 2. A lint filter 9 for capturing lint and the like contained in air exhausted from the rotating drum 2 and a filter cover 10 for protecting the lint filter 9 from clothing are attached to the exhaust port 8.

A blower 11 for circulating air is provided behind the rotary drum 2. A blower 11 includes a double-sided fan 12 rotatably supported on a support shaft 7.
And a fan casing 13 accommodating the double-sided fan 12. A partition member 14 is provided in the fan casing 13 so as to surround the double-sided fan 12.
And a cooling air passage 16. The peripheral edge of the double-sided fan 12 and the partition member 14 are connected by a labyrinth, so that air cannot flow between the drying air passage 15 and the cooling air passage 16.

An opening 17 for taking in air into the drying air passage 15 is formed on a surface of the fan casing 13 facing the rotary drum 2. A seal member 18 is provided between the rotary drum 2 and the fan casing 13 to guide exhaust air from an exhaust port 8 formed on the rear surface of the rotary drum 2 to the drying air passage 15. In the drying air passage 15, a drum outlet thermistor H for detecting the temperature of the air flowing into the drying air passage 15 from the rotating drum 2 (hereinafter referred to as "drum outlet temperature") is provided. I have. On the other hand, the cooling air passage 16 is communicated with the outside of the housing 1 through an outside air inlet 19 and an outside air outlet 20 formed in the rear plate 1 b of the housing 1.

A circulation duct 21 is provided below the rotating drum 2.
Are arranged. One end of the circulation duct 21 is connected to a drying air passage 15 defined in the fan casing 13, and the other end of the circulation duct 21 is connected to a hot air inlet 22 formed at a lower portion of the drum support plate 6. ing. Thereby, the rotating drum 2 and the drying air path 1
5 and the circulation duct 21 form an air circulation path.

A semiconductor heater 23 for heating the air flowing through the circulation duct 21 is disposed near the hot air inlet 22 in the circulation duct 21. Semiconductor heater 23
Is provided with a first heating element 23a and a second heating element 23b composed of, for example, a positive temperature coefficient thermistor. Can be switched between strong and weak. Further, a thermostat 70 is disposed below the drum support plate 6 near the semiconductor heater 23 to prevent air near the semiconductor heater 23 from being in an abnormally high temperature state.

A motor 26 having front and rear output shafts 24 and 25 is provided at a lower part in the housing 1. A drum pulley 27 is fixed to an output shaft 24 extending forward of the motor 26. An endless drum belt 28 is wound between the drum pulley 27 and the outer periphery of the rotary drum 2.
The power is transmitted to the rotary drum 2 via the drum 7 and the drum belt 28. In order to prevent slippage between the drum belt 28 and the rotary drum 2 and the drum pulley 27, the idler pulley 2
9 provides an appropriate tension.

On the other hand, the output shaft 2 extending rearward of the motor 26
5 is provided with a fan pulley 30. An endless fan belt 32 is wound between the fan pulley 30 and a pulley 31 provided at the center of the double-sided fan 12. Therefore, when the motor 26 is rotationally driven, the driving force of the motor 26 is transmitted to the rotary drum 2 and the double-sided fan 12 via the drum belt 28 and the fan belt 32, and the rotary drum 2 and the double-sided fan 12
Rotates.

When the double-sided fan 12 is rotated, the air in the drying air passage 15 is sent to the circulation duct 21. The air sent to the circulation duct 21 is heated by the semiconductor heater 23 to become high-temperature hot air, and flows into the rotary drum 2 through the hot air inlet 22. In the rotating drum 2, the hot air and the clothing are stirred by the rotation of the rotating drum 2, and heat exchange is performed between the hot air and the clothing. As a result, the moisture contained in the clothes is evaporated. Air containing moisture evaporated from the clothes is sucked into the drying air passage 15 by the rotation of the double-sided fan 12.

The double-sided fan 12 is cooled by the outside air taken into the cooling air passage 16 from the outside air inlet 19 by the rotation thereof and discharged from the outside air outlet 20 by the rotation, and removes the moisture flowing into the drying air passage 15. The contained air is cooled by the cooled double-sided fan 12. Thereby, the drying air path 1
The water contained in the air inside 5 condenses on the surface of the double-sided fan 12 to form water droplets. The water droplets are blown from the inside of the fan casing 13 to the circulation duct 21 by the rotation of the double-sided fan 12, and are drained to the outside from a drain port 33 formed at a lower portion of the circulation duct 21. The air with reduced moisture is sent to the circulation duct 21 again by the rotation of the double-sided fan 12, and repeatedly circulates through the air circulation path formed by the rotating drum 2, the drying air path 15 and the circulation duct 21. Thereby, the clothes in the rotating drum 2 are dried.

FIG. 2 is a plan view showing the structure of the operation panel 40 arranged on the front surface of the housing 1. A plurality of push switches for the user to input various command signals to the clothes dryer are arranged on the operation panel 40. Specifically, a power switch 41 for turning on the power, a start / stop key 42 for starting and stopping the operation of the clothes dryer, and a type of clothes from a plurality of driving courses set in advance. And a course selection key 43 for selecting a driving course according to the quantity and quantity.
A heater setting key 44 for switching the output of the semiconductor heater 23 (see FIG. 1) between high and low is provided.

The operation panel 40 also includes a plurality of course LEDs 45 for displaying which operation course has been selected in accordance with the course selection by the course selection key 43, and the intensity of the heater output set by the heater setting key 44. Heater LED 46 and heater weak L for displaying
An ED 47 and a clogging LED 48 for notifying clogging of the lint filter 9 are arranged.

FIG. 3 is a block diagram showing an electrical configuration of the clothes dryer. Each section of the clothes dryer operates by AC power supplied from a commercial AC power supply 50. Specifically, the semiconductor heater 2
The third first heating element 23a is connected in series to the commercial AC power supply 50 via the power switch 41, the load switch 51, and the thermostat 70, thereby forming a power supply circuit for the first heating element 23a. . First heating element 23
a, the power supply switch 41, the load switch 51, and the thermostat 70 are all on and the commercial AC power supply 5
A voltage from 0 (for example, 100 V) is applied. The second heating element 23b of the semiconductor heater 23 is connected in series to the commercial AC power supply 50 via the power switch 41 and the load switch 52, and when both the power switch 41 and the load switch 52 are on, the commercial AC power supply 50 Is applied.

The motor 26 is connected in series to a commercial AC power supply 50 via a power switch 41 and a load switch 53. Therefore, the voltage from the commercial AC power supply 50 is supplied to the motor 26 with both the power switch 41 and the load switch 53 being on. Commercial AC power supply 5
0 further includes a power switch 41 and a load switch 5
4 and an APO (Auto Power Off) 55 is connected. The APO 55 is for automatically shutting off the power supply to each part after the operation of the clothes dryer is completed. When the load switch 54 is turned on, the APO 55 is turned on (on state). Power switch 41 is turned off (off state).

Further, the commercial AC power supply 50
A transformer 56 for lowering the power supply voltage of 00V is connected via the power supply switch 41. Power switch 4
When 1 is turned on, the voltage from the commercial AC power supply 50 is applied to the primary coil of the transformer 56, thereby inducing a secondary voltage lower than the power supply voltage in the secondary coil of the transformer 56. The induced secondary voltage is
The voltage is reduced to 5 V by a power supply circuit 57 connected to 6 and used as an operating voltage of a microcomputer 60 for controlling the operation of each section of the clothes dryer.

The microcomputer 60 includes a CPU and R
It is composed of a memory including an AM and a ROM.
The microcomputer 60 receives, for example, a pulse from a clock 61 composed of a crystal oscillator and detection signals from a substrate thermistor L and a drum exit thermistor H via a thermistor input circuit 62. The microcomputer 60 is connected to a thermostat detection circuit 63 for detecting on / off of a thermostat 70 provided in a power supply circuit of the first heating element 23a. A signal is input. The microcomputer 60 further includes
Signals from push switches including a power switch 41, a start / stop key 42, a course selection key 43, and a heater setting key 44 disposed on the operation panel 40;
A signal is input from a door switch 64 that is turned on / off as the door 3 shown in FIG. 1 is opened and closed.

The microcomputer 60 is connected to a load drive circuit 65 for controlling on / off of the load switches 51, 52, 53, 54. The microcomputer 60 outputs / stops a drive signal to the load drive circuit 65 based on signals input from the substrate thermistor L, the drum exit thermistor H, and the like, and controls on / off of the load switches 51, 52, 53, 54. By doing so, the semiconductor heater 23, the motor 26 and the APO 57
To control the drive of. The load switches 51, 52, 5
A switching element such as a triac or a relay can be used for 3, 54.

The microcomputer 60 has LEDs 45, 46, 47,
48 and a buzzer 66 for notifying that the operation of the clothes dryer has been completed are connected.
To control the drive of. FIGS. 4, 5, and 6 are flowcharts showing the flow of the drying process according to the first embodiment of the present invention. In this drying process, four flags of a thermo state flag, a thermo out flag, a heater state flag, and a time drying flag are used. These four flags are set when the power to the clothes dryer is turned on (power switch 41
Is turned on), the flag is reset to 0.

The thermostat flag is set in the thermostat 70.
Is a flag indicating the on / off state of the thermostat 70. When the thermostat 70 is stable in the on state (conductive state),
When the thermo state flag is set to 1 and is stable in the off state (cutoff state), the thermo state flag is reset to 0. The thermo end flag is a flag indicating whether the thermo state flag has been rewritten from 1 to 0 twice or more during the drying operation. If the thermo state flag is rewritten from 1 to 0 twice or more during the drying operation, the thermo end determination flag is set to 1.

The heater state flag is a flag indicating the output state of the semiconductor heater 23. Heater status flag = 1
Indicates that the output of the semiconductor heater 23 is set to “strong”, and the heater state flag = 0 indicates that the semiconductor heater 2
3 indicates that the output is set to “weak”. The time drying flag is a flag indicating whether or not a drying operation by time control described later is being executed. When the drying operation by the temperature control described later is completed and the drying operation by the time control is started, the time drying flag is set to 1.

In this drying process, the thermostat for measuring the time elapsed since the thermostat 70 was turned on or off, and the number of times the thermostat flag was rewritten to 1 or 0 are counted. And a time drying counter for measuring the elapsed time from the start of the drying operation by time control. These counters are, for example, RA built in microcomputer 60.
It can be constituted by a RAM counter provided in M, and the count value is cleared to 0 when the power is turned on.

Referring to FIG. 4, when the clothes to be dried are stored in the rotating drum 2 by the user, the power switch 41 is pressed to turn on the power, and then the start / stop key 42 is pressed ( First, the thermo state flag is set to 1 (YES in step S1) (step S1).
2). Then, it is checked whether the heater weak LED 47 is on or off (step S3).

If the output of the semiconductor heater 23 is set to "strong", the heater weak LED 47 is set in step S3.
Is determined to be off. Then, the state of the thermo-out decision flag is checked (step S4), and the heater state flag is set / reset according to the state of the thermo-out decision flag (steps S5, S6). Since the thermo end determination flag is reset when the power is turned on, it is determined that the thermo end determination flag = 0 at this time, and the heater state flag is set to 1 (step S5).

On the other hand, when the output of the semiconductor heater 23 is set to "weak", the heater weak LE is set in step S3.
D47 is determined to be in the lighting state, and the heater state flag is kept at 0 (step S6). In the following, description will be made on the assumption that the output of the semiconductor heater 23 is set to “strong”. Next, the state of the time drying flag is checked (step S7). Since the time drying flag is reset when the power is turned on, it is determined that the time drying flag = 0 at this time. Then, step S7
To step S8 shown in FIG.
It is determined whether 0 is on or off.
Immediately after the start / stop key 42 is pressed and the operation is started, the thermostat 70 is normally in the ON state.

When it is determined that the thermostat 70 is in the on state, the state of the thermo state flag is checked (step S9). Since the thermo status flag has been rewritten from 0 to 1 in step S2, it is determined that the thermo status flag = 1 at this time. Then, the count value of the thermo counter is cleared (step S10). Thereafter, the substrate thermistor L and the drum outlet thermistor H
It is determined whether or not the drying operation based on the temperature control based on the output is completed (step S11). The drying operation by the temperature control is an operation performed to dry the clothes to a predetermined state (for example, a state in which 94% of the moisture contained in the clothes is removed), and the drying operation by the temperature control ends. It is determined whether or not the temperature difference between the drum outlet temperature detected by the drum outlet thermistor H and the substrate temperature detected by the substrate thermistor L is equal to or greater than a predetermined end reference value. In other words, while the clothes are wet, the heat of the hot air blown into the rotary drum 2 is taken away by the clothes, so that the drum outlet temperature becomes relatively low. small. On the other hand, when the clothes are dried, the hot air blown into the rotary drum 2 is exhausted as it is, so that the temperature at the drum outlet becomes relatively high, so that the temperature difference between the drum outlet temperature and the substrate temperature increases. Therefore, if the temperature difference between the drum outlet temperature and the substrate temperature when the clothes are dried by an experiment or the like is obtained, and the end reference value is appropriately set from the obtained temperature difference, the difference between the drum outlet temperature and the substrate temperature is obtained. By determining whether or not the temperature difference has become equal to or greater than the termination reference value, it can be determined whether or not the clothes in the rotating drum 2 have dried. At this time, since the drying operation by the temperature control has not been started, the determination in step S11 is naturally denied.

If it is determined that the drying operation by the temperature control is not completed, the state of the heater state flag is checked (step S12), and the drying operation by the temperature control according to the state of the heater state flag is performed. Heater status flag = 1
In the case of the first heating element 23a and the second heating element 23b
Is started (step S1).
3, S14), the motor 26 is turned on, and the rotary drum 2 and the double-sided fan 12 are driven to rotate (step S1).
5). Thereby, a relatively high-temperature hot air is blown into the rotating drum 2.

On the other hand, when the heater status flag = 0,
The power supply to only the first heating element 23a is started (steps S16 and S17), and the motor 26 is turned on to rotate the rotating drum 2 and the double-sided fan 12 (step S18). Thereby, a relatively low-temperature hot air is blown into the rotary drum 2. In this description, since it is assumed that the heater output is set to “strong”, it is determined that the heater state flag = 1 in step S12, and both the first heating element 23a and the second heating element 23b are transmitted. Is started.

When the drying operation under the temperature control is started in this way, the process returns to step S3 shown in FIG. 4, and until the drying operation under the temperature control is determined to be completed in step S11 in FIG. The processing is performed, and the drying operation by the temperature control is continued. During the drying operation by the temperature control, the supply of electric power to the first heating element 23a is controlled based on the output of the drum outlet thermistor H. Specifically, when the drum outlet temperature detected by the drum outlet thermistor H becomes equal to or higher than a predetermined temperature,
The load switch 51 (see FIG. 3) is turned off, and the power supply to the first heating element 23a is cut off. When the temperature of the hot air decreases and the temperature detected by the temperature sensor becomes lower than a predetermined temperature, the load switch 51 is turned on, and the power supply to the first heating element 23a is restarted. Thereby, the temperature of the hot air circulating in the rotating drum 2 is kept substantially constant, so that it is possible to prevent the clothes from being damaged by heat and from affecting the dryer body by heat.

After that, the drying operation by the temperature control is continued, and when the temperature difference between the drum outlet temperature and the substrate temperature becomes equal to or more than a predetermined end reference value, it is determined that the drying operation by the temperature control is ended in step S11. The process proceeds to step S19, and the time drying flag indicating whether or not the drying operation by the time control is started is rewritten from 0 to 1. Then, a time during which the drying operation by the time control should be continued (hereinafter, referred to as “time control operation time”) is set (step S20), and the drying operation is continuously performed for the set time.

In step S20, the time control operation time is set based on the table stored in the ROM in the microcomputer 60. Specifically, for example, an experiment is used to determine the relationship between the time during which the drying operation under temperature control is performed and the time required for the clothing to completely dry from a predetermined drying state, and this relationship is tabulated. And stored in the ROM. Step S2
At 0, the time from the start to the end of the drying operation by the temperature control is given to the table as an address, and the time read from the table by the address designation is set as the time control operation time. Thereby, at the end of the time-controlled drying operation, the clothes in the rotating drum 2 can be completely dried.

By the way, when the drying operation is started in a state where the lint filter 9 attached to the exhaust port 8 of the rotary drum 2 is clogged with lint or the like, or is almost clogged. During the drying operation by the above-mentioned temperature control, the vicinity of the semiconductor heater 23 becomes high temperature (for example, 70 ° C. or more), and the thermostat 70
Is assumed to be turned off. Once the thermostat 70 is turned off during the drying operation by the temperature control, the on / off of the thermostat 70 is repeated thereafter, so that the power supply amount to the semiconductor heater 23 is controlled and the drum outlet temperature does not rise. There is a possibility that the temperature difference between the drum outlet temperature and the substrate temperature does not exceed the above-mentioned end reference value, and the drying operation by the temperature control does not end. Therefore, in this drying process, if the thermo state flag is rewritten from 1 to 0 two or more times during the drying operation by the temperature control, it is determined that the clothes in the rotating drum 2 are almost dry, and the temperature at that time is determined. The drying operation by the control is ended and the drying operation by the time control is started.

Specifically, when the thermostat 70 is turned off during the drying operation by the temperature control, step S in FIG.
From 8, the process proceeds to step S <b> 21, and the state of the thermostat flag is checked. When the thermostat 70 is turned off for the first time, the thermostat flag is set to 1 and therefore, it is determined that the thermostat flag = 1 in step S21. Then, the number of clock pulses input from the clock 61 to the microcomputer 60 is counted by the thermo-counter, so that the elapsed time from when the thermostat 70 switches from on to off is measured (step S22).

When the counting operation of the thermo counter is started, it is next determined whether or not the count value of the thermo counter has become equal to or greater than a count value corresponding to 10 seconds (step S23). That is, it is determined whether 10 seconds have elapsed since the thermostat 70 was switched from on to off. Until ten seconds elapse after the thermostat 70 is turned off, step S23 is performed.
Then, the process returns to step S11, and the drying operation by the above-described temperature control is continued. During that time, the state of the thermostat 70 is repeatedly checked. And thermostat 7
If the OFF state of 0 continues for 10 seconds or more, the thermo state flag is rewritten from 1 to 0 (step S24), and the thermo extinguishing number counter for counting the number of times the thermo state flag is rewritten to 1 or 0 is set to "1". Is incremented to "" (step S25).

The reason why the thermostat flag is rewritten after 10 seconds have passed since the thermostat 70 was turned off is to prevent poor drying of clothes due to chattering of the thermostat 70. That is, the thermostat 70 causes a phenomenon that the on / off is frequently repeated for a while after the on / off is switched, that is, a so-called chattering. Therefore, if the thermostat flag is rewritten in response to the on / off of the thermostat 70 due to the chattering, the thermostat 70 is not rewritten.
Immediately after turning off for the first time, rewriting of the thermo state flag from 1 to 0 is detected twice, and the drying operation by temperature control ends. Also, due to the influence of noise, for example, the thermostat detection circuit 63
There is a possibility that the ON / OFF state of 0 may be erroneously detected. Therefore, when ten seconds have elapsed since the on / off of the thermostat 70 was switched, it is determined that the state of the thermostat 70 has become stable, and the thermostat flag is rewritten.

When the thermo-out count counter is incremented in step S25, it is checked whether or not the incremented count value of the thermo-out count counter has reached "2" (step S26). At this time, since the count value of the thermoout count counter is "1", the determination in step S26 is denied and step S11 is performed.
The drying operation by the above-described temperature control is further continued.

When the drying operation by the temperature control is continued while the thermostat 70 is in the off state, the semiconductor heater 23
, The ambient temperature near the semiconductor heater 23 gradually decreases. When the ambient temperature in the vicinity of the semiconductor heater 23 drops to, for example, 60 ° C. or lower, the thermostat 70 switches from off to on. When the thermostat 70 switches from off to on, step S8
It is determined that the thermostat 70 is on, and the state of the thermo state flag is checked in step S9. At this time, since the thermo state flag = 0, step S9 is executed.
Then, the process proceeds to step S27, where the counting operation of the thermo counter is started. That is, the elapsed time from when the thermostat 70 switches from off to on is measured. When the on state of the thermostat 70 continues for 10 seconds or more (step S28), the thermostat 7
It is determined that 0 is stable in the ON state, and the thermo state flag is rewritten from 0 to 1 (step S29).

Thereafter, while the thermostat 70 is turned on, a drying operation is further performed by temperature control. When the ambient temperature near the semiconductor heater 23 becomes 70 ° C. or more again, the thermostat 70 switches from on to off again. Then, it is determined in step S8 that the thermostat 70 is off, and the state of the thermostat flag is checked in step S21. At this time, the thermo state flag =
Since it is 1, the process proceeds to step S22, and the elapsed time from when the thermostat 70 switches from the on state to the off state is measured. When the off state of the thermostat 70 continues for 10 seconds or more (step S23),
The thermo state flag is rewritten from 1 to 0 (step S24), and the thermo extinguishing number counter is incremented to “2” (step S25).

When the number-of-times-of-thermo-times counter becomes "2", the number-of-times-of-thermo-times counter becomes "2" in step S26.
The determination as to whether or not the thermostat state flag has been rewritten from 1 to 0 twice is rewritten from 0 to 1 (step S3).
0). Then, the time drying flag is rewritten from 0 to 1 (step S31), a time during which the drying operation by the time control is to be continued is set (step S32), and the drying operation by the time control is started. Step S3
In step 2, similarly to the processing in step S20 described above,
A time control operation time corresponding to the time when the drying operation by the temperature control is performed is set.

When the time for performing the drying operation by the time control is set in step S20 or step S32, the process returns to step S3 in FIG. 4, and it is determined whether the heater weak LED 47 is on or off. Under the above assumption, it is determined that the heater weak LED 47 is turned off, and then the state of the thermo-off determination flag is checked (step S4).

If the thermo-out determination flag = 0, the heater status flag is set to 1 (step S5).
Then, since the time drying flag = 1, step S7
Then, the process proceeds to step S33 in FIG. 6, where the counting operation of the time drying counter is started, and the elapsed time from the start of the drying operation by the time control is measured. The count value of the time drying counter is constantly monitored (step S
34) The process returns from step S34 to step S12 in FIG. 5 until the elapsed time after the start of the count operation reaches the time control operation time set in step S20 in FIG.
At this time, since 1 is set in the heater state flag, steps S12 to S13, S14, S1 are performed.
After step 5, the process returns to step S3. Thereby, while the drying operation by the time control is continued in the state where the output of the semiconductor heater 23 is “strong”, when the thermo-out judgment flag = 1,
That is, if the thermo status flag is rewritten from 1 to 0 twice or more during the drying operation by the temperature control, the heater status flag is reset to 0 regardless of the strength of the heater output set by the heater setting key 44. (Step S6). Then, the time drying flag is set (=
Since step 1), step S7 to step S3 in FIG.
Proceeding to 3, the count operation of the time drying counter is started. Thereafter, it is determined whether or not the elapsed time after the start of the count operation has reached the time control operation time set in step S32 of FIG. 5 (step S34). Step S in FIG.
Return to 12. At this time, since the heater status flag is set to 0, steps S12 to S1 are performed.
After step S17 and step S18, the process returns to step S3. Thus, the drying operation by time control is performed while the output of the semiconductor heater 23 is “weak”. In this embodiment, the processing of steps S4 and S6 corresponds to the function of the heater control means.

When the time control operation time set in step S20 or step S32 in FIG. 5 elapses after the drying operation by the time control is performed and the counting operation of the time drying counter is started, step S34 is performed.
, It is determined that the drying operation has been completed.
1 and 52 are turned off, and the power supply to the first heating element 23a and the second heating element 23b is cut off (step S35).
Then, with the semiconductor heater 23 turned off, the motor 26
By driving only (step S37), low-temperature outside air is sent into the rotating drum 2 to start a blowing operation for cooling the hot clothing.

In this blowing operation, the temperature at the outlet of the drum was 40 ° C.
It continues until it becomes below (step S38). When the temperature at the drum outlet becomes 40 ° C. or less, the motor 26
After the power supply to the power supply is interrupted (step S39), the buzzer 66 is sounded to notify that the blowing operation has ended (step S40), and the drying process ends.

As described above, in the drying process shown in FIGS. 4 to 6, the thermostat 70 is turned on during the drying operation by the temperature control for drying the clothes in the rotating drum 2 to a predetermined state. If the switching from the state to the off state is detected two or more times, the drying operation by the temperature control is terminated at that time, and the drying operation by the time control is started. Thus, even when the thermostat 70 is provided, the temperature difference between the drum outlet temperature and the substrate temperature does not exceed the predetermined end reference value, so that the drying operation by the temperature control does not end. Does not occur.

If the switching of the thermostat 70 from the ON state to the OFF state is detected twice or more during the drying operation by the temperature control, regardless of the strength of the heater output set by the heater setting key 44, In a state where the output of the semiconductor heater 23 is "weak", the drying operation by the time control is executed. Accordingly, even when the lint filter 9 is becoming clogged, the change in the ambient temperature in the vicinity of the semiconductor heater 23 becomes gentle, so that the number of times the state of the thermostat 70 switches during the drying operation by the time control is controlled. Can be reduced. Therefore, the life of the thermostat 70 can be extended.

In the above-described drying process, the drying operation by the temperature control is terminated when the switching of the thermostat 70 from the ON state to the OFF state is detected two or more times. The drying operation by the temperature control may be ended at the time of operation, or the drying operation by the temperature control may be ended at the time of operating the thermostat 70 three or more times.

FIGS. 7 and 8 are flowcharts showing the flow of the drying process according to the second embodiment of the present invention.
In the drying process according to the second embodiment, in addition to the heater status flag and the time drying flag that are also used in the drying process according to the first embodiment described above, two flags, a high limiter flag and a thermo cut-off flag, are used. Is done. These four flags are reset to 0 when the power to the clothes dryer is turned on.

The high limiter flag is a flag indicating whether or not the high limiter temperature has been fixed. The high limiter flag = 1 indicates that the high limiter temperature is fixed, and the high limiter flag = 0 indicates that the high limiter temperature is not yet fixed. The high limiter temperature is a criterion for switching the first heating element 23a from on to off in the on / off control of the first heating element 23a performed to keep the temperature of the hot air flowing in the rotary drum 2 constant. Is the temperature at which

The flag indicating that the thermostat has run out is a flag indicating whether or not the thermostat 70 has been operated to switch from on to off during the drying operation by time control. The flag indicating that the thermostat has run out remains at 0 while the thermostat 70 is not operating, and is set to 1 when the thermostat 70 operates. In this drying process,
The thermo counter and the time drying counter used in the drying processing according to the above-described first embodiment are used. These counters have a count value = 0 when the power is turned on.
Is cleared.

Referring to FIG. 7, when the clothes to be dried are stored in the rotating drum 2 by the user, the power switch 41 is pressed and the power is turned on, and then the start / stop key 42 is pressed. First, it is checked whether the heater weak LED 47 is turned on or off (step T2). If the output of the semiconductor heater 23 is set to "strong", the process proceeds to step T2.
It is determined that the heater weak LED 47 is turned off, and the heater state flag indicating the output state of the semiconductor heater 23 is set to 1
(Step T3). On the other hand, when the output of the semiconductor heater 23 is set to “weak”, it is determined that the heater weak LED 47 is lit in step T2, and the heater state flag is kept at 0 (step T2).
4).

Next, the state of the time drying flag indicating whether or not the drying operation by the time control has been started is checked (step T5). Since the time drying flag is reset when the power is turned on, it is determined that the time drying flag = 0 at this time. Then, it is determined whether or not the drying operation by the temperature control is completed (step T6). If it is determined that the drying operation by the temperature control is not completed, the state of the high limiter flag is checked (step T9). At this time, since the high limiter flag has been reset to 0, the process proceeds from step T9 to step T10, where the high limiter temperature is set. The high limiter temperature is set to a different value depending on various conditions such as the heater output set by the heater setting key 44, the substrate temperature detected by the substrate thermistor L, and the drying operation time. For example, when the heater output is set to “strong”, the substrate temperature is relatively high, and immediately after the start of the drying operation, the high limiter temperature is set to 80 ° C. When the heater output is set to “weak”, the substrate temperature is relatively low, and immediately after the start of the drying operation, the high limiter temperature is 70 ° C.
Is set to

When the high limiter temperature is set, the state of the thermo-out flag is checked (step T1).
1). At the start of this process, the flag indicating that the thermostat has run out is set to 0.
Is skipped from step T11 to step T37, and it is determined whether or not the drum outlet temperature detected by the drum outlet thermistor H is equal to or higher than the high limiter temperature. Immediately after the start of operation, since the drum outlet temperature is lower than the high limiter temperature, the determination in step T37 is denied, and the process proceeds to step T14, where the state of the heater state flag is checked. Then, the drying operation according to the state of the heater state flag is started.

If the drum outlet temperature becomes higher than or equal to the high limiter temperature during the drying operation, the judgment in step T37 is affirmed, and the process proceeds to step T13, where the high limiter flag is rewritten from 0 to 1. As a result, in the subsequent processing, the high limiter flag = 1 in step T9.
Then, the process goes to step T14, so that the high limiter temperature is not changed until the high limiter flag is rewritten to 0 next time.

If it is determined in step T14 that the heater status flag is 1, the first heating element 23a and the second heating element 23
b is started (step T1).
5, T16), the motor 26 is turned on, and the rotating drum 2 and the double-sided fan 12 are rotationally driven (step T1).
7). On the other hand, when the heater state flag is 0, the energization of only the first heating element 23a is started (step T).
18, T19), the motor 26 is turned on and the rotating drum 2
And the double-sided fan 12 is rotationally driven (step T2).
0).

When the drying operation by the temperature control is started in this way, the process returns to step T2, and the above-described processes after step T3 are performed until the drying operation by the temperature control is determined to be completed in step T6. Drying operation is continued. During the drying operation by the temperature control, the supply of power to the first heating element 23a is controlled based on the output of the drum outlet thermistor H and the set high limiter temperature and low limiter temperature. Specifically, when the drum outlet temperature detected by the drum outlet thermistor H becomes equal to or higher than the high limiter temperature, the power supply to the first heating element 23a is cut off. Then, the temperature of the hot air decreases, and the temperature of the drum outlet decreases to the low limiter temperature (for example,
When the temperature becomes lower than the high limiter temperature (-1 ° C.), the power supply to the first heating element 23a is restarted. In this embodiment, the processing of steps T15 and T18 corresponds to the function of the means for turning on / off the heater.

Thereafter, when the drying operation by the temperature control is continued and the temperature difference between the drum outlet temperature and the substrate temperature becomes equal to or higher than a predetermined end reference value, it is determined in step T6 that the drying operation by the temperature control is ended. Determined Step T
Proceeding to 7, the time drying flag is rewritten from 0 to 1. Then, a drying operation time by time control is set (step T8).

After the time control operation time has been set in step T8, the above-described processing after step T9 is performed. Then, returning to step T2, the heater weak LED 47
Is turned on or off again, and the heater weak LE
After the heater state flag is set / reset according to the state of D (steps T3 and T4), the state of the time drying flag is checked (step T5). At this time, since the time drying flag has been rewritten to 1, the process proceeds from step T5 to step T21 in FIG. 8, where the counting operation of the time drying counter is started, and the elapsed time from the start of the drying operation by the time control. Is measured.

The count value of the time drying counter is constantly monitored (step T22), and the process proceeds from step T22 to step T23 until the elapsed time after the start of the count operation reaches the time set in step T8 in FIG. ,
During the drying operation by the time control, the state of the thermo-cut-off flag indicating whether the thermostat 70 is operated and switched from on to off is checked. Since the thermo-off flag is reset to 0 at the start of the process, it is determined in step T23 that the thermo-off flag = 0.
Next, the on / off state of the load switch 51 for controlling the energization of the first heating element 23a is checked (step T24). The on / off state of the load switch 51 can be detected based on the state of a command signal output from the microcomputer 60 to the load drive circuit 65.

When it is determined that the load switch 51 is on, the on / off of the thermostat 70 is checked (step T25). Then, if the thermostat 70 is in the ON state, the count value of the thermo-out count counter is cleared (step T26). When it is determined that the load switch 51 is in the off state,
The on / off state of the thermostat 70 cannot be checked,
The thermo-out counter is cleared (step T2).
6).

Here, the ON / OFF state of the thermostat 70 is not determined when the load switch 51 is in the OFF state. Is not accurately detected. That is, when the load switch 51 is off, the thermostat 7
Since no current flows to 0, the thermostat 70 is turned on / off.
This is because the thermostat 70 is determined to be in the off state regardless of the off state.

When the thermo-out count counter is cleared, the process returns from step T26 to step T9 in FIG. 7, and the state of the high limiter flag indicating whether or not the high limiter temperature is fixed is checked. If the drum outlet temperature has never reached the high limiter temperature or higher, the high limiter flag and the thermo-out flag are set to 0.
, So that steps T9 to T10,
The process proceeds to step T14 via T11 and T37, and the state of the heater state flag is checked. If the drum outlet temperature is equal to or higher than the high limiter temperature and the high limiter flag has already been rewritten to 1, step T9
Skip to step T14. When it is determined in step T14 that the heater state flag is 1, the process returns from step T14 to step T2 via steps T15, T16, and T17, and the drying operation by time control is performed while the output of the semiconductor heater 23 is "strong". Done. If the heater status flag is 0, the process returns from step T14 to step T2 via steps T18, T19, and T20, and the drying operation by time control is performed while the output of the semiconductor heater 23 is "weak".

Thereafter, steps T2 to T5 described above are performed.
The processes of T21 to T26, T9 to T20, and T37 are repeatedly performed, and the drying operation by time control is advanced. Then, during the drying operation by the time control, the semiconductor heater 23
When the ambient temperature rises and the thermostat 70 is switched from on to off, the switching of the thermostat 70 is detected in step T25 in FIG. 8 and the counting operation of the thermo counter is started (step S25). T27).

When the counting operation of the thermo counter is started, it is next determined whether or not the count value of the thermo counter has become equal to or greater than the count value corresponding to 10 seconds (step T28). That is, it is determined whether 10 seconds have elapsed after the thermostat 70 was switched from on to off. Until ten seconds elapse after the thermostat 70 is turned off, step T28
Then, the process returns to step T9 in FIG. 7, and the drying operation by the time control is continued. During this time, the state of the thermostat 70 is repeatedly checked. If the thermostat 70 is kept off for 10 seconds or more, the process proceeds from step T28 to step T29, and the flag indicating that the thermostat has run out is rewritten from 0 to 1. After the high limiter flag is reset to 0 (step T38), the time control operation time is extended by 10 minutes (step T30). The processing in step T30 corresponds to the function of the time extension means.

Here, the reason why the thermostat flag is rewritten 10 seconds after the on / off state of the thermostat 70 switches is based on, for example, erroneous detection of the thermostat detection circuit 63 due to the influence of noise.
This is to prevent the time control operation time from being extended. At step T30, the flag indicating that the thermostat has run out is rewritten to 1, so that in the subsequent processing, step T30 is executed.
At 23, it is determined that the thermo-out flag = 1, and the processing of steps T24 to T30 is skipped, so that the time control operation time is not further extended.

If the time control operation time is extended in step T30, the flow returns to step T9 in FIG. 7, and since the high limiter flag is 0, the high limiter temperature is set to a value corresponding to the above conditions. (Step T10) The state of the flag indicating that the thermostat has run out is checked (Step T1).
1). If the OFF state of the thermostat 70 is detected for 10 seconds or longer, the flag indicating that the thermostat has run out has been rewritten from 0 to 1 in step T29.
At 11, it is determined that the flag indicating that the thermo-out has occurred = 1.
The high limiter temperature is reset to a value obtained by subtracting a predetermined temperature α (for example, 5 ° C.) from the currently set high limiter temperature (step T12). For example, if the heater output is “strong” and the high limiter temperature is set to 80 ° C., it is reset to 75 ° C. obtained by subtracting 5 ° C. from 80 ° C. The process in step T12 corresponds to the function of the high limiter temperature changing unit.

In step T12, the high limiter temperature is 5 ° C.
When the value is reset to a low value, the process proceeds to step 37, where the magnitude of the drum outlet temperature is compared with the high limiter temperature. Until the drum outlet temperature becomes equal to or higher than the high limiter temperature, the drying operation is continued while the high limiter flag is kept at 0. The supply of power to the first heating element 23a is controlled as the high limiter temperature. And if the drum outlet temperature becomes higher than the high limiter temperature,
The high limiter flag is rewritten to 1 (step T
13) After that, the drying operation is continued based on the high limiter temperature set last in step T12.

When the time set in step T8 elapses after the drying operation based on the time control is performed and the counting operation of the time drying counter is started, FIG.
In step T22, it is determined that the drying operation is completed, and the power supply to the first heating element 23a and the second heating element 23b is interrupted (steps T31 and T32). Then, only the motor 26 is driven with the semiconductor heater 23 turned off (step T33), and low-temperature outside air is sent into the rotating drum 2 to start a blowing operation for cooling the high-temperature clothing. I do.

In this blowing operation, the temperature at the drum outlet is 40 ° C.
It is continued until it becomes below (step T34). When the temperature at the drum outlet becomes 40 ° C. or less, the motor 26
After the power supply to the power supply is cut off (step T35), the buzzer 66 is sounded to notify that the blowing operation has ended (step T36), and the drying process ends.

As described above, in the processing according to the second embodiment, if the switching of the thermostat 70 from the on state to the off state is detected during the drying operation by the time control, the time control is performed. The drying operation time is extended by a predetermined time (10 minutes). As a result, the total amount of heat supplied into the rotary drum 2 during the time control operation can be kept substantially constant. Therefore, even if the thermostat 70 operates during the drying operation by the time control, the clothes in the rotating drum 2 can be dried well.

Further, when the switching of the thermostat 70 from the on state to the off state is detected during the drying operation by the time control, the high limiter temperature is lowered by a predetermined temperature. As a result, in the subsequent drying operation, before the thermostat 70 is turned off, the load switch 51 is turned off and the power supply to the first heating element 23a is cut off. The number of times of switching can be reduced. Therefore, the life of the thermostat 70 can be extended.

In the above description, it is assumed that the time control operation is extended by a predetermined time (10 minutes). However, the time to be extended is such that the thermostat 70 is turned off during the drying process. The time may be set to an appropriate time based on the remaining time of the time-controlled operation at the time. For example, if the remaining time of the time control operation is small, set the time to be extended to a relatively short time,
If the remaining time is long, the time to be extended may be set to a relatively long time. If the remaining time of the time control operation is small, it is considered that the clothes have been sufficiently dried by the drying operation up to that time. Therefore, even if the additional extension time is short, no moisture remains in the clothes. In addition, when the remaining time of the time control operation is long, the moisture contained in the clothes can be completely removed by setting the additional extension time to be long.

FIGS. 9 and 10 are flowcharts showing the flow of the drying process according to the third embodiment of the present invention. In the drying process according to the third embodiment, it is possible to detect whether or not the lint filter 9 is clogged during the execution of the drying operation. In the drying process according to the third embodiment, in addition to the heater state flag indicating the output state of the semiconductor heater 23, two flags, a temperature confirmation flag, a substrate temperature flag, and a clogging control flag, are used. These four flags are reset to 0 when the power to the clothes dryer is turned on.

The temperature confirmation flag is a flag indicating whether or not the substrate temperature has been confirmed to detect clogging during the drying operation. The temperature confirmation flag = 1 indicates that the substrate temperature has been confirmed, and the temperature confirmation flag = 0 indicates that the substrate temperature has not been confirmed. The substrate temperature flag is a flag indicating whether the substrate temperature is equal to or higher than 30 ° C. or lower than 30 ° C. If the substrate temperature is 30 ° C. or higher, the substrate temperature flag is set to 1 and the substrate temperature is set to 30 ° C.
If the temperature is lower than 0 ° C., the substrate temperature flag is reset to “0”.

The clogging control flag is a flag indicating whether or not clogging control described later is being executed, and is rewritten from 0 to 1 when the clogging control is started. In the drying process, an operation time counter for measuring an elapsed time from the start of the drying process, a clogging detection time counter for measuring a time in which the clogging state of the lint filter 9 is continuously detected, and A clogging delay time counter that measures an elapsed time after it is determined that the lint filter 9 is clogged is used. These counters are, for example, the microcomputer 60
Can be configured by a RAM counter provided in a RAM incorporated in the microcomputer 60. By counting the number of clock pulses input from the clock 61 to the microcomputer 60, the elapsed time can be measured. These counters have a count value =
Cleared to 0.

In the following description, it is assumed that the clogging LED 48 for notifying that the lint filter 9 is clogged at the start of the drying process. Referring to FIG. 9, when the clothes to be dried are stored in the rotating drum 2 by the user, the power switch 41 is pressed and the power is turned on, and then the start / stop key 42 is pressed (step E1). YES), first, the heater weak LED 47
It is checked whether is turned on or off (step E2).

When the heater weak LED 47 is off,
In other words, when the output of the semiconductor heater 23 is set to “strong”, the process proceeds from step E2 to step E3, and it is checked whether the clogging LED 48 is on or off. Immediately after the start of the drying process, clogging L
It is determined that the ED 48 is turned off, the process proceeds to step E4, and 1 is set to the heater status flag (step E4).

On the other hand, when the heater weak LED 47 is turned on, in other words, when the output of the semiconductor heater 23 is set to "weak", the heater state flag is kept at 0 (step E5). In the following, description will be made on the assumption that the output of the semiconductor heater 23 is set to “strong”. When the heater state flag is set or reset, the counting operation of the drying time counter is started, and the measurement of the elapsed time from the start of this process is started (step E6). The count value of the time drying counter is constantly monitored (step E7). Until the elapsed time after the start of the count operation reaches 30 minutes, the process proceeds from step E7 to step E8 to determine whether the drying operation is completed. You. The end of the drying operation is determined based on whether or not the temperature difference between the drum outlet temperature and the substrate temperature is equal to or higher than a predetermined end reference value. If it is determined that the drying operation has not been completed, the state of the heater state flag is checked (step E9), and the drying operation is performed according to the state of the heater state flag.

When the heater status flag = 1, energization of both the first heating element 23a and the second heating element 23b is started (steps E10 and E11), and the motor 26 is turned on to turn the rotating drum 2 on. And the double-sided fan 12 is rotationally driven (step E12). On the other hand, when the heater state flag is 0, the power supply to only the first heating element 23a is started (steps E13 and E14), and the motor 26 is turned on to rotate the rotary drum 2 and the double-sided fan 12 (steps E13 and E14). Step E15).

When the drying operation is started in this manner, the process returns to step E2, and until the time measured by the drying time counter reaches 30 minutes in step E7.
The processing after step E2 described above is repeated. When the time measured by the drying time counter reaches 30 minutes (YES in step E7), the process proceeds to step E16 in FIG. 10, and the state of the temperature confirmation flag is checked. At this time, the substrate temperature was not checked for clogging detection.
Since the temperature confirmation flag is still reset to 0 at the start of the process, it is determined in step E16 that the temperature confirmation flag is zero. When it is determined that the temperature confirmation flag is 0, the output of the substrate thermistor L is referred to, and it is checked whether or not the substrate temperature detected by the substrate thermistor L is 30 ° C. or higher (step E17). And when the substrate temperature is 3
If the temperature is 0 ° C. or higher, the substrate temperature flag is rewritten from 0 to 1 (step E18), and if the substrate temperature is lower than 30 ° C., the substrate temperature flag is kept at 0 (step E19). When the substrate temperature flag is set or reset, the temperature confirmation flag is rewritten from 0 to 1 (Step E20).

After the temperature confirmation flag is rewritten, it is determined whether the clogging LED 48 is on or off (step E21). If the clogging LED 48 is off, the lint filter 9 is turned off. It is checked whether or not it is in a clogged state (steps E22 to E28).
If the lint filter 9 is clogged, the exhaust from the inside of the rotating drum 2 cannot be performed well,
The high-temperature air created by heating the semiconductor heater 23 stays near the semiconductor heater 23. Semiconductor heater 2
3 has a positive temperature characteristic, the semiconductor heater 23
As the ambient temperature increases, the calorific value decreases. Therefore, when the lint filter 9 is clogged,
The drum outlet temperature detected by the drum outlet thermistor H does not increase so much. On the other hand, since the substrate temperature detected by the substrate thermistor L is substantially constant, the drying operation continues while the temperature difference between the drum exit temperature detected by the drum exit thermistor H and the substrate temperature detected by the substrate thermistor L is small. Will be.

Therefore, in steps E22 to E28, the difference between the temperatures detected by the drum exit thermistor H and the substrate thermistor L and the determination reference value determined according to the combination of the substrate temperature flag and the heater status flag are determined. The magnitudes are compared, and when the detected temperature difference between the two thermistors H and L is equal to or smaller than the determination reference value, it is determined that the lint filter 9 is in a clogged state. In this embodiment, the processing of steps E22 to E28 corresponds to the function of the temperature determining means.

The above-mentioned criterion value is determined according to the following table.

[0112]

[Table 1]

For example, if substrate temperature flag = 1 (substrate temperature is 30 ° C. or higher) and heater state flag = 1
If (the heater output is “strong”), the determination reference value is set to 10 deg. Then, it is determined whether or not the temperature difference between the drum outlet temperature and the substrate temperature at this time is 10 deg or less. If the temperature difference between the drum outlet temperature and the substrate temperature is larger than the reference value, it is determined that the lint filter 9 is not clogged, and the clogging detection time counter is reset (= 0). (Step E
29), the process returns to step E8 in FIG. 9, and it is determined whether the drying operation is completed. If the drying operation is not completed, the process proceeds to step E9, and the above-described processing is repeatedly performed. At this time, since 1 is set in the temperature confirmation flag, it is determined in step E16 that the temperature confirmation flag is 1, and the processing in steps E17 to E20 is skipped.
That is, the substrate temperature flag is not rewritten again. Then, the blowing operation is performed until the drum outlet temperature becomes lower than 40 ° C. (Steps E38, E39, E4).
0, E41), when the temperature at the drum outlet falls below 40 ° C.
After the power supply to the motor 26 is interrupted (step E4)
2) Then, a notification that the blowing operation has been completed is given (step E36), and the drying process ends.

On the other hand, when the temperature difference between the drum outlet temperature and the substrate temperature is equal to or smaller than the judgment reference value, the lint filter 9
Is determined to be in a clogged state, and the elapsed time thereafter is measured by a clogging detection time counter (step E30). When the counting operation of the clogging detection time counter is started, it is determined whether or not the count value has reached a count number corresponding to 150 minutes (step E31). When the count number corresponding to 150 minutes has not been reached, the process returns to step E8 in FIG. 9, and it is determined whether or not the drying operation has ended. If the drying operation is not completed, the process proceeds to step E9, and the above-described processing is repeatedly performed. During this time, it is repeatedly determined whether or not the lint filter 9 is in a clogged state in steps E24 to E28. Will be

When the lint filter 9 is clogged, the state in which the temperature difference between the drum outlet temperature and the substrate temperature is small as described above continues, and it is determined that the drying operation is completed in step E8 in FIG. Eventually, the count value of the clogging detection time counter reaches the count number corresponding to 150 minutes. If it is determined that the count value has reached the count number corresponding to 150 minutes, the clogging LED 48
Is turned on (step E32), and after the clogging delay time counter is reset (step E33), the process returns to step E8 in FIG. 9, and the above-described processing is repeated. In this embodiment, the processing of steps E30 and E31 corresponds to the function of the clogging detecting means.

Although the lint filter 9 is not clogged, the temperature difference between the drum outlet temperature and the substrate temperature is smaller than the judgment reference value in steps E24, E25, E27 and E28 due to the influence of noise and the like. It may be determined that there is. Also in such a case, it is determined that the lint filter 9 is in the clogged state, and the counting operation of the clogging detection time counter is started. However, since this is temporary, it is immediately determined that the temperature difference between the drum outlet temperature and the substrate temperature is larger than the determination reference value, and the count value of the clogging detection time counter is cleared in step E29. You. This can eliminate the possibility that the lint filter 9 is erroneously determined to be clogged.

After the clogging LED 48 is turned on, it is determined in step E21 that the clogging LED 48 is turned on. Then, from step E21 to step E3
Proceeding to 4, the state of the clogging control flag is checked.
Since the clogging control flag is reset at the start of the process, it is determined that the clogging control flag is 0 immediately after the clogging LED 48 is turned on. When it is determined that the clogging control flag is 0, the counting operation of the clogging delay time counter is started, and the elapsed time from when the clogging LED 48 is turned on is measured (step E35).

Thereafter, it is determined whether or not the count value of the clogging delay time counter has reached the count number corresponding to 15 minutes. If it is determined that the count value has not yet reached, the process returns to step E8 in FIG. Then, the process returns to step E2 via steps E9 to E15, and it is determined whether the heater weak LED 47 is turned on or off. If the heater weak LED 47 is off, it is determined whether the clogging LED 48 is on or off. At this time, since the clogging LED 48 is lit, the heater status flag is reset to 0 regardless of the strength of the heater output set by the heater setting key 44. Therefore, thereafter, the drying operation is performed in a state where the output of the semiconductor heater 23 is “weak”, that is, in a state where the second heating element 23b is turned off.

When the drying operation is continued while the output of the semiconductor heater 23 is "weak" and 15 minutes have passed since the clogging LED 48 was turned on, the count value of the clogging delay time counter corresponds to 15 minutes. After it is determined that the count number has been reached and the clogging control flag is set to 1 (step E37), the process returns to step E8 in FIG. 9 to determine whether the drying operation has ended. At this time, since the clogging control flag is set to 1, the end reference value for determining the end of the drying operation is reduced. Then, the magnitude of the changed clogging reference value is compared with the temperature difference between the drum exit temperature and the substrate temperature. If the temperature difference between the drum exit temperature and the substrate temperature is larger than the clogging reference value, It is determined that the drying operation has been completed.

After it is determined that the drying operation has been completed,
The blowing operation is performed until the drum outlet temperature becomes lower than 40 ° C. (steps E38, E39, E40, E41),
When the temperature at the drum outlet falls to 40 ° C. or lower, after the power supply to the motor 26 is cut off (step E42), a notification that the air blowing operation has ended is issued (step E36), and the drying process ends.

As described above, according to the third embodiment, it is possible to determine whether or not the lint filter 9 is clogged based on the temperatures detected by the drum outlet thermistor H and the substrate thermistor L. It is not necessary to additionally provide a sensor dedicated to detecting clogging of the lint filter 9 or the like. Therefore, the product cost can be reduced as compared with a clothes dryer having a configuration including a current sensor.

If it is determined that the lint filter 9 is in the clogged state, the heater setting key 4
Regardless of the strength of the heater output set by step 4,
The drying operation is performed when the output of the semiconductor heater 23 is “weak”. Thus, even when the lint filter 9 is clogged, there is no possibility that the clothing near the hot air inlet 22 formed in the rotary drum 2 may be damaged by heat. In addition, since the output of the semiconductor heater 23 is set to “weak”, the change in the ambient temperature in the vicinity of the semiconductor heater 23 becomes gentle, so that the number of times the thermostat 70 is turned on / off during the drying operation can be reduced. The life of the thermostat 70 can be extended.

Further, in this drying process, a criterion value for determining whether or not the lint filter 9 is in a clogged state depends on the substrate temperature detected by the substrate thermistor L and the output of the semiconductor heater 23. Will be changed accordingly. That is, when the substrate temperature is low or when the semiconductor heater 23
Is large, the temperature difference between the substrate temperature and the drum outlet temperature becomes relatively large, so the determination reference value is set to a relatively large value. On the other hand, when the substrate temperature is high or when the output of the semiconductor heater 23 is small, the temperature difference between the substrate temperature and the drum outlet temperature is relatively small, so the determination reference value is set to a relatively small value. Thereby, the clogging state of the lint filter 9 can be accurately detected.

If it is determined that the lint filter 9 is clogged, the termination reference value, which is used as a criterion for determining whether to terminate the drying operation, is reduced. Therefore, when the lint filter 9 is clogged, there is no possibility that the drying operation is not terminated because the temperature difference between the drum outlet temperature and the substrate temperature does not exceed the termination reference value.

Further, the end reference value is determined by the lint filter 9
Is lowered after a predetermined time (for example, 15 minutes) elapses after it is determined that the is clogged. This allows
Unlike the case where the end reference value is lowered immediately after detecting the clogging of the lint filter 9, the drying operation is performed with the heater output being “weak” for a while after the clogging is detected, and the clogging is performed. Since the drying operation does not end at the point of detecting, moisture can be completely removed from the clothes.

FIG. 11 is a flowchart showing a flow of a thermo-abnormality detecting process for detecting an abnormal state of the thermostat 70. The thermo-abnormality detection process is a process for checking whether or not the thermostat 70 has an abnormality such as a contact failure, and is performed 15 minutes after the start of the drying operation. When the drying operation is started (step P
1), the counting operation of the operation time counter is started,
The elapsed time after that is measured (step P2). Then, it is determined whether or not the time measured by the operation time counter has reached 15 minutes (step P3). If the time has not reached 15 minutes, the state of the thermostat 70 is checked (step P4).

If the thermostat 70 is on,
The counting operation of the thermo counter is started, and the time during which the thermostat 70 is kept on is measured (step P5). When the counting operation of the thermo counter is started, it is determined whether or not the count value has reached the count number corresponding to 10 seconds (step P6). Until the count value reaches 10 seconds, return to Step P2,
The above-described processing after step P2 is repeated.

If the on state of the thermostat 70 continues for 10 seconds, it is determined that the thermostat 70 is normal, and the thermostat 70 indicating whether the thermostat 70 is normal or abnormal is provided.
The K flag is set to 1 (step P7). In addition,
The thermo OK flag has been reset to 0 at the start of the drying operation. When 1 is set to the thermo OK flag,
Returning to Step P2, the processes of Steps P2 to P7 are repeatedly performed until 15 minutes have elapsed since the start of the drying operation.

On the other hand, in step P4, the thermostat 70
Is determined to be in the OFF state, the count value of the thermo counter is cleared (step P8). Then, the process returns to Step P2, and the processes of Steps P2, P3, P4, and P8 are repeated until 15 minutes have elapsed since the start of the drying operation or until the thermostat 70 is turned on.

By the time 15 minutes have passed since the start of the drying operation, the thermostat 70 was switched on,
Thereafter, when the thermostat 70 is kept on for 10 seconds, the thermo OK flag is set to 1. Conversely, within 15 minutes from the start of the drying operation, the thermostat 70
Is not turned on, the thermo OK flag is kept reset to 0.

After 15 minutes have passed since the start of the drying operation, the state of the thermo-OK flag is checked (step P9). If the thermo-OK flag is set to 1, the thermostat 70 is normal. If it is determined that the thermostat 70 is present and the thermo OK flag is still reset to 0, it is determined that the thermostat 70 has an abnormality. When there is an abnormality in the thermostat 70, for example, the drying operation is forcibly terminated, and the abnormality in the thermostat 70 is notified, and then, the thermo-abnormality detection processing ends.

It is assumed that the thermostat 70 is erroneously detected as being on due to the influence of noise or the like, even though the thermostat 70 is off. Also in such a case, the process proceeds from Step P4 to Step P5, and the counting operation of the thermo counter is started. However, since this is temporary, the thermostat 70 is immediately determined to be in the off state, and the count value of the thermo counter is cleared in step P8. Thereby, the accuracy of detecting the abnormality of the thermostat 70 by the thermo-abnormality detection processing can be improved.

Further, for example, if the power is turned off during the execution of the drying operation and a new drying operation is started immediately after the forced termination of the drying operation, the first drying operation is started at the time when the drying operation is started. Since the load switch 51 for controlling the energization of the heating element 23a is off, the thermostat detection circuit 63 may determine that the thermostat 70 is off. In this case, if the time for performing the thermo-abnormality detection processing is short, the processing ends without turning on the load switch 51, and it is determined that the thermostat 70 has an abnormality. Therefore, in the processing shown in FIG. 11, the time for performing the thermo-abnormality detection processing is set to an appropriate time (for example, 15 minutes), and the load switch 51 is always turned on at least once during the execution of the thermo-abnormality detection processing. It is supposed to. Therefore, even in the case described above, there is no possibility that the thermostat 70 is erroneously determined to be abnormal.

As described above, in the thermo-abnormality detection processing, the thermostat 70 can be properly detected. Therefore, by performing the thermo-abnormality detection process in parallel with the drying process according to the first embodiment or the second embodiment, it is possible to prevent the thermostat 70 from being abnormal and the drying operation from being performed satisfactorily. Can be prevented.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. For example, in the description of the above embodiment,
Drying process (first embodiment) on the assumption that switching of the thermostat from on to off is detected during the drying operation by temperature control (first embodiment), and switching from on to off of the thermostat during the drying operation by time control And a drying process (second embodiment) that assumes a case where is detected. However, it is most preferable that the above two drying processes are combined so that a good drying operation is realized even if the thermostat is turned off during either the drying operation by the temperature control or the drying operation by the time control.

In the first embodiment, in order to reduce the number of times that the state of the thermostat is switched during the drying operation performed after the detection of the switching of the thermostat from on to off, the output of the heater is increased in the first embodiment. In the second embodiment, the high limiter temperature, which is a reference for turning off the heater, is reduced.
However, conversely, the number of times the thermostat is switched may be reduced by lowering the high limiter temperature in the first embodiment and lowering the heater output in the second embodiment.

Various other design changes can be made within the scope of the technical matters described in the claims.

[0138]

According to the first to fifth aspects of the present invention,
Even in the configuration in which the thermostat is provided in the power supply circuit to the heater, the drying operation for drying the clothes can be favorably performed. According to the invention as set forth in claims 6 to 8, it is possible to detect the clogging of the filter satisfactorily without additionally providing a new component such as a current sensor for detecting the amount of current to the heater.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a schematic configuration of a clothes dryer according to an embodiment of the present invention.

FIG. 2 is a plan view showing a configuration of an operation panel.

FIG. 3 is a block diagram showing an electrical configuration of the clothes dryer.

FIG. 4 is a flowchart illustrating a flow of a drying process according to the first embodiment.

FIG. 5 is a flowchart illustrating a flow of a drying process according to the first embodiment.

FIG. 6 is a flowchart illustrating a flow of a drying process according to the first embodiment.

FIG. 7 is a flowchart illustrating a flow of a drying process according to a second embodiment.

FIG. 8 is a flowchart illustrating a flow of a drying process according to a second embodiment.

FIG. 9 is a flowchart illustrating a flow of a drying process according to a third embodiment.

FIG. 10 is a flowchart illustrating a flow of a drying process according to a third embodiment.

FIG. 11 is a flowchart illustrating a flow of a thermo-abnormality detection process.

[Explanation of symbols]

 2 Rotary Drum 9 Lint Filter 11 Blower 23 Semiconductor Heater 23a First Heating Element 23b Second Heating Element 26 Motor 60 Microcomputer (Operation Control Means) 62 Thermistor Input Circuit 63 Thermostat Detection Circuit (State Detection Means) 65 Buzzer H Drum Exit Thermistor (1st temperature sensor) L Substrate thermistor (2nd temperature sensor)

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yoshihiro Inamoto 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd.

Claims (8)

[Claims] 1. A rotary drum for storing clothes to be dried, a blower for forming an air flow in the rotary drum, and a heater for heating air sent into the rotary drum by the blower. And a thermostat provided in a power supply circuit for the heater, for shutting off / conducting power to the heater based on the ambient temperature around the heater, and detecting whether the thermostat is in a cutoff state or a conducting state. During the drying operation performed by driving the heater and the blower, based on the detection of the switching of the thermostat from the conductive state to the cutoff state by the state detecting means, And a driving control unit for ending the driving. 2. A rotary drum for storing clothes to be dried, a blower for forming an air flow in the rotary drum, and a heater for heating air sent into the rotary drum by the blower. And a thermostat provided in a power supply circuit for the heater, for shutting off / conducting power to the heater based on the ambient temperature around the heater, and detecting whether the thermostat is in a cutoff state or a conducting state. During the drying operation performed by driving the heater and the blower, based on the detection of the switching of the thermostat from the conductive state to the cutoff state by the state detecting means, And a time extending means for extending a time to perform the operation by a predetermined time. 3. During the drying operation performed by driving the heater and the blower, the state detecting means detects the switching of the thermostat from the conductive state to the cutoff state, and causes the rotary drum to move into the rotating drum. 3. The clothes dryer according to claim 1, further comprising heater control means for controlling the heater so as to reduce the amount of heat supplied per predetermined time. 4. The heater includes a plurality of heating elements, and the output can be changed by selectively turning on / off the plurality of heating elements. 4. The heater according to claim 3, wherein the output of the heater is reduced in response to the state detection means detecting the switching of the thermostat from the conductive state to the cutoff state a predetermined number of times.
The clothes dryer as described. 5. The apparatus according to claim 1, further comprising a first temperature sensor for detecting a temperature of air exhausted from said rotary drum, wherein said heater control means sets a temperature detected by said first temperature sensor to be higher than a predetermined high limiter temperature. Means for turning off the heater, and then turning on the heater when the temperature detected by the first temperature sensor becomes equal to or lower than a predetermined low limiter temperature, and switching from the conductive state of the thermostat to the cutoff state by the state detecting means. 4. The clothes dryer according to claim 3, further comprising: high limiter temperature changing means for lowering the high limiter temperature by a predetermined temperature in response to the detection of the temperature. 6. A rotary drum for storing clothes to be dried, a blower for forming an air flow in the rotary drum, and a heater for heating air sent into the rotary drum by the blower. A filter mounted on an exhaust port formed in the rotary drum for removing foreign substances contained in air exhausted from the rotary drum, and detecting a temperature of air exhausted from the rotary drum A first temperature sensor, a second temperature sensor for detecting a temperature of a place where the influence of the heat generated by the heater is eliminated, and a temperature detected by the first temperature sensor and a second temperature sensor.
Temperature determining means for calculating a difference from the temperature detected by the temperature sensor and determining whether or not the calculated detected temperature difference is equal to or smaller than a predetermined determination reference value; And the temperature difference between the temperature detected by the second temperature sensor and the temperature detected by the second temperature sensor is determined to be equal to or less than the determination reference value,
Clogging detection means for detecting that the filter is clogged. 7. The clogging detecting means is determined by the temperature determining means that a temperature difference between a temperature detected by the first temperature sensor and a temperature detected by the second temperature sensor is equal to or smaller than a determination reference value. 7. The clothes dryer according to claim 6, wherein when the state continues for a predetermined time, the filter is determined to be clogged. 8. The heater has a plurality of heating elements, the output of which can be changed by selectively turning on / off the plurality of heating elements. 8. The clothes dryer according to claim 6, further comprising a heater output control unit that reduces an output of the heater when it is detected that the filter is clogged. 9.