JP3224959B2 - Clothes dryer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clothes dryer having a function of judging clogging of a filter from a current flowing through a PTC heater.

[0002]

2. Description of the Related Art Conventionally, in a clothes dryer, a wind passing through a drying chamber is heated by a PTC heater (a semiconductor heater having a positive temperature characteristic) to generate warm air, and the clothes to be dried are dried in the drying chamber by the warm air. Is provided. Further, a filter is provided for the drying chamber, and the wind (warm air) passed through the drying chamber is also passed through the filter, so that lint scattered exclusively from the clothes to be dried is captured. .

[0003] In this case, however, if the filter becomes clogged, the flow of air in the drying chamber deteriorates, and the drying efficiency decreases. Also, when that happens, PT
The amount of wind in contact with the C heater is also reduced, thereby reducing the PTC
Since the current flowing through the heater decreases, the current flowing through the PTC heater is detected, the detected value is compared with a set value, and when the detected value is smaller than the set value, it is determined that the filter is clogged. There are provided lamps that operate to notify the user.

[0004]

In the case of the above, the filter can be cleaned by the user based on the notification by the operation of the buzzer or the lamp, so that the drying efficiency can be prevented from further lowering. However, among the usage conditions of the clothes dryer, especially the power supply voltage differs depending on the region, and there are high and low levels. For this reason, the detection value of the current flowing through the PTC heater also varies, and depending on the area, the detection value of the PTC heater current is large even though the filter is sufficiently clogged, and it cannot be determined that the filter is clogged.
Alternatively, even though the filter has not yet been clogged, there has been a problem that the detection value of the PTC heater current is small and the filter is erroneously determined to be clogged.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and therefore has as its object to provide a clothes dryer capable of accurately determining whether a filter is clogged without being affected by variations in power supply voltage. Another object of the present invention is to provide a clothes dryer that can more accurately determine clogging of a filter without being affected by fluctuation factors of the clothes.

[0006]

Means for Solving the Problems To achieve the above object, in the clothes dryer of the present invention, first, the wind passing through the drying chamber and the filter is heated by a PTC heater to generate warm air. By detecting the current flowing through the PTC heater when drying the clothes to be dried in the drying chamber,
Compares the set value and the detected value, in the one that determines that the clogging of the filter when the detected value is smaller than the set value, the power supply voltage detecting means for detecting a power supply voltage, the drying chamber
Indirectly or directly detect the speed of the fan that produces the draft
And a rotation speed detecting means for outputting the set value, and changing the set value to a value corresponding to the level of the detected power supply voltage and the detected rotation speed based on the detection result.

[0007]

[0008] In the clothes dryer of the present invention, secondly,
The air passing through the drying chamber and the filter is heated by the PTC heater.
Temperature weathered Te, the dried clothes above Symbol drying chamber by this hot air
The current flowing through the PTC heater when drying
Output value, and compares the detected value with the set value.
What is judged as filter clogging when smaller than the value
There are a, a power supply voltage detecting means for detecting a power supply voltage, and a clothing amount detecting means for detecting the amount of the dry clothes drying chamber
Together comprising, characterized in that from their detection results to vary to a value corresponding to the set value to the level of the detected power supply voltage and detecting garment weight.

[0009]

Third , in the clothes dryer of the present invention,
Current detecting means for detecting a current flowing through the PTC heater, wherein the wind passing through the drying chamber and the filter is heated by a PTC heater to generate warm air, and the heated air is used to dry the clothes to be dried in the drying chamber; A drying operation is performed based on a predetermined operation, and a value detected by the current detecting means at that time is written in the memory, and a difference between the written value and a value detected by the current detecting means during normal operation is provided. Is determined to be a filter clogging when is greater than or equal to a set value.

[0011]

According to the first means, the set value to be compared with the detected value of the PTC heater current that changes with the power supply voltage level is also a value corresponding to the power supply voltage level. Accurate filter clogging that is not affected can be determined. Also, the detected value of the PTC heater current is
Varies depending on the number of rotations of the fan that generates the air that passes through the drying chamber.
The fan speed is also detected.
The set value is detected as the power supply voltage level and fan rotation speed.
The power supply voltage and fan rotation
A more accurate filter that is not affected by
Clogging can be determined.

Further, the detected value of the PTC heater current varies depending on the amount of clothing to be dried in the drying room. In contrast, according to the second means, the amount of clothing to be dried is also detected and set. Since the value is a value corresponding to the level of the power supply voltage and the detection result of the amount of the clothes to be dried,
It is possible to determine the clogging of the filter more accurately without being affected by the variation in the amount of the filter.

On the other hand, according to the third means, the value written in the nonvolatile memory is originally a value corresponding to the power supply voltage in the area of use, and the clogging of the filter is determined based on the value. In addition, it is possible to accurately determine whether the filter is clogged without being affected by variations in the power supply voltage, without necessarily detecting the power supply voltage.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the basic configuration will be described with reference to FIGS. First, FIG. 4 shows an outer box 1 of the entire clothes dryer. A clothes entrance 2 is formed in the center of the front part, and a door 3 for opening and closing the entrance 2 is pivotally provided.
A drum 4 constituting a drying chamber is disposed inside the outer box 1, and a front portion of the drum 4 is fixed by an opening 5 to a portion around the clothes entrance 2 in the outer box 1. 6 is rotatably supported, and the rear part is also rotatably supported by a center shaft 7 on a rear drum support 8 erected at the rear middle part of the outer box 1. A casing 9 is provided between the drum 4 and the drum rear support 8, and a fan 10 is rotatably mounted on the center shaft 7 of the drum 4 in the casing 9. are doing.

Here, the fan 10 is a double wing shape having a front wing portion 10a and a rear wing portion 10b, and is made of a heat exchange material (heat transfer material) so that it can also function as a dehumidifier as described later. The rotation is driven by a motor 11 disposed in the upper part of the outer box 1 outside the drum 4 via a pulley 12, a belt 13, and a pulley 14.
The drum 4 is rotatably driven by the motor 11 via a pulley 15 and a belt 16.

The rear half of the casing 9 has a central portion formed with an outside air passage 17 formed in the rear support 8 of the drum, and an outer case back plate 1.
8 communicates with the outside of the machine through an outside air inlet 19 formed at the center, and a lower portion thereof communicates with the outside of the machine through an outside air return port 20 formed at the lower portion of the outer case back plate 18.

On the other hand, in the front half of the casing 9, the center portion of the filter 2 is formed by an intake port 21 formed in the casing 9 and an exhaust port 22 formed in the rear center portion of the drum 4.
3 communicates with the inside of the drum 4 with the lower part being connected to an air outlet 24 formed in the casing 9, a connecting duct 25 connected thereto, and a heater duct 2 connected to the connecting duct 25.
6 and a warm air outlet 27 formed in the lower part of the front part of the drum front support 6 and communicates with the inside of the drum 4. A PTC heater 28 is disposed in the heater duct 26. In particular, the PTC heater 28 includes a first heater 28a and a second heater 28b as shown in FIG.

FIG. 5 shows the main components of the control circuit. The microcomputer 29, which is the center of the control circuit, functions as control means. DC power is supplied. The microcomputer 29 has a voltage detecting circuit 32 functioning as a power supply voltage detecting means.
, A power supply voltage detection signal is input from the current detection circuit 33, a current detection signal is input from a current detection circuit 33 functioning as current detection means, and a rotation speed detection signal is further input from a rotation sensor 34 functioning as rotation speed detection means. A temperature detection signal is input from a temperature sensor 35 functioning as a temperature detection unit, and a clothing amount detection signal and a dryness detection signal are input from an electrode 36 functioning as a clothing amount detection unit and a drying degree detection unit and a detection processing circuit 37. It has become.

The power supply voltage detection circuit 32 detects the voltage of the power supply 30, and has a circuit configuration shown in FIG. The current detection circuit 33 is provided with the PTC heater 2.
The circuit configuration mainly includes a current transformer 38 shown in FIG. Furthermore,
The rotation sensor 34 detects the rotation speed of the fan 10. Specifically, the rotation sensor 34 indirectly detects the rotation speed of the fan 10 by detecting the rotation speed of the motor 11. Alternatively, the rotation speed of the fan 10 may be detected indirectly by detecting the rotation speed of the drum 4, or the rotation speed of the fan 10 may be directly detected. In addition, the temperature sensor 35 detects the temperature of the hot air discharged from the inside of the drum 4, and is disposed at the intake port 21 of the casing 9. It detects the amount and the degree of dryness, and is attached to the lower part of the drum front support 6 so as to face the inside of the drum 4.

In addition, the microcomputer 2
9, various switch signals are input from a switch input unit 39 including various switches, a storage signal is fetched from a non-volatile memory 40, and a clock pulse is input from a clock pulse generation circuit 41. Based on these inputs and a control program stored in advance, the microcomputer 29 controls the motor 11, the PTC heater 28 (first heater 28a and second heater 28b), and the buzzer 4
A drive control signal is supplied to a drive circuit 43 for driving the memory 2, and a write signal is supplied to the memory 40. A power switch 44 is connected to a circuit from the power supply 30 to the motor 11, the PTC heater 28, and the buzzer 42.

Next, the operation of the above configuration will be described. When the operation is started, the microcomputer 29 operates as shown in FIG.
As shown in the figure, the PTC heater 28 (first heater 28a
And the second heater 28b) and the motor 1
1 (step A1).

Then, the motor 11 rotates the drum 4 from the pulley 15 via the belt 16 and simultaneously drives the fan 1 from the pulley 12 via the belt 13 and the pulley 14.
Rotate 0. The rotation of the fan 10 causes the air in the drum 4 to pass through the filter 23, and from the exhaust port 22 of the drum 4 to the intake port 21 of the casing 9, the front half of the casing 9, the exhaust port 24, the connection duct 25, the heater duct 26, and is returned into the drum 4. Also, from behind the outer case 1, air outside the machine passes through the outside air inlet 19 of the outer case back plate 18, the outside air passage 17, the rear half portion of the casing 9, and the outside air return opening 20 in that order. Thus, in the casing 9, the air inside the drum 4 and the air outside the outer box 1 are heat-exchanged in contact with the fan 10 in the casing 9, and the air inside the drum 4 is dehumidified. Then, the dehumidified air is heated by the PTC heater 28 in the process of passing through the heater duct 26 to turn into hot air, and is supplied into the drum 4 to be used for drying clothes to be dried (not shown).

After the drying operation is started, the microcomputer 29 determines whether or not the PTC heater 28 is operating (step A2). The detection value of the current flowing through the PTC heater 28 is read and stored based on the detection signal from the detection circuit 33 (step A3). In this case, the current detection circuit 3
The current detection signal from 3 is converted into a voltage and given. Next, the power supply 30 is detected by a detection signal from the voltage detection circuit 32.
Is detected (step A4), and a set value serving as a reference for subsequent filter clogging determination is changed from the read value to a value corresponding to the level of the detected power supply voltage and determined (step A5).

FIG. 2 shows the contents of the determination. If the detected power supply voltage is less than 92 [V], the set value is 3.6.
[V] and the detected power supply voltage is 92 [V] or more, 95
If it is less than [V], the set value is determined to be 3.5 [V],
If the detected power supply voltage is equal to or higher than 95 [V] and lower than 98 [V], the set value is determined to be 3.4 [V] (see the figure for the others). That is, the higher the detected power supply voltage, the smaller the set value.

Then, the determined set value is compared with the detected value of the PTC heater 28 current read and stored in step A3 to determine whether or not the detected value is smaller than the set value (step A6). ). Here, FIG. 3 shows the relationship between the power supply voltage and the current of the PTC heater 28 when the filter 23 is clogged. As the power supply voltage increases, the heat generation of the PTC heater 28 increases.
This shows that the PTC heater 28 current eventually becomes smaller due to the self-controllability inherent to the heater 28. Therefore, it is effective that the set value is made smaller as the power supply voltage detected as described above is higher. If it is determined that the detected value of the current of the PTC heater 28 is smaller than the set value, the time counting is started. (Step A7), and thereafter, it is determined whether or not the count time has reached 20 [seconds] (Step A8). If it is determined that the count time has not reached, it is time to end the operation. (Step A
9) If it is determined that it is not time to finish, the process returns to step A1.

On the other hand, if it is determined in step A8 that the count time has reached 20 [seconds] (the situation where the detection value is determined to be smaller than the set value has continued for 20 [seconds]),
The buzzer 42 determines that the filter 23 is clogged.
(Step A1).
0). In this case, a lamp may be operated instead of the buzzer 42.

When it is determined in step A2 that the PTC heater 28 is not in operation, and in step A6
If it is determined that the detected value is not smaller than the set value, the counter that has counted the time is reset (step A11), and the process proceeds to step A9. or,
If it is determined in step A9 that it is time to end the operation, the power supply to the PTC heater 28 and the motor 11 is stopped (step A12), and the operation is ended.

As described above, according to the present configuration, the detected value of the current of the PTC heater 28 that changes with the level of the power supply voltage is:
Since the set value to be compared with the set value is set to a value corresponding to the level of the power supply voltage, it is possible to accurately determine whether the filter is clogged without being affected by variations in the power supply voltage.

8 to 10 show a first embodiment of the present invention. In this case, the microcomputer 29 includes steps A1 to A1 of the above-described basic configuration .
After the same steps B1 to B4, the rotation sensor 34
The rotational speed of the motor 11 and, consequently, the rotational speed of the fan 10 are read in accordance with the detection signal (step B5), and the set values are detected from the read value and the read value of the power supply voltage in step B4. (Step B6).

FIG. 9 shows the contents of the determination, in which the detected power supply voltage is less than 92 [V] and the number of revolutions of the motor 11 is 12
If it is less than 10 [rpm], the set value is 3.55 [V].
And if it is 1210 [rpm] or more, the set value is determined to be 3.65 [V]. Also, if the detected power supply voltage is 92
If it is not less than [V] and less than 95 [V], and the rotation speed of the motor 11 is less than 1210 [rpm], the set value is 3.45.
[V], and if it is 1210 [rpm] or more, the set value is determined to be 3.55 [V]. Further, if the detected power supply voltage is not less than 95 [V] and less than 98 [V], and the rotation speed of the motor 11 is less than 1210 [rpm], the set value is 3.
It is determined to be 35 [V], and if it is equal to or more than 1210 [rpm], the set value is determined to be 3.45 [V] (see the figure for the others). That is, the higher the detected power supply voltage, the lower the set value, and at the same time, the higher the rotational speed of the motor 11, the larger the set value.

Then, step A6 of the basic configuration
Through steps B7 to B13 similar to steps A7 to A12, in particular, 20 [seconds] in step B9 with the detection value in step B3 determined to be smaller than the set value in step B7.
If it is determined that the filter 2 has been reached, in step B11 the filter 2
3 is notified that the clogging is clogged.

FIG. 10 shows the relationship between the number of revolutions of the motor 11 and the current of the PTC heater 28 when the filter 23 is clogged.
This indicates that the current flowing through the PTC heater 28 increases because the rotation speed of the fan 10 increases and the wind passing through the drum 4 increases. Therefore, as the rotation speed of the motor 11 detected as described above increases, the set value increases. This makes it possible to accurately determine whether the filter is clogged without being affected by not only the power supply voltage but also the variation in the rotation speed of the motor 11 (the rotation speed of the fan 10).

FIGS. 11 to 13 show a second embodiment of the present invention. In this case, the microcomputer 29 performs steps C1 to C4 similar to steps A1 to A4 of the basic configuration , and thereafter, the electrodes 36 and The amount of the clothes to be dried in the drum 4 is read by the detection signal from the detection processing circuit 37 (step C5), and the set value is detected from the read value and the read value of the power supply voltage in step C4. The value is changed to a value corresponding to the level of the amount and determined (step C6).

FIG. 12 shows the contents of the determination. When the detected power supply voltage is less than 92 [V], If it is 1.5 kg or more and less than 3.0 kg,
It is determined to be 3.6 [V], and if it is 3.0 [kg] or more,
It is determined to be 3.55 [V]. Also, if the detected power supply voltage is 92
[V] or more and less than 95 [V], and the amount of clothing to be dried is 1.
If it is less than 5 [kg], the set value is determined to be 3.55 [V]. If it is 1.5 [kg] or more and less than 3.0 [kg], it is determined to be 3.5 [V]. If it is not less than 3.0 [kg], it is determined to be 3.45 [V]. Further, if the detected power supply voltage is not less than 95 [V] and less than 98 [V], and the amount of clothing to be dried is less than 1.5 [kg], the set value is 3.45 [V].
Is determined to be 1.5 [kg] or more and less than 3.0 [kg], and is determined to be 3.4 [V]. If it is 3.0 [kg] or more, 3.35 [V] is determined. (Refer to the figure for others). That is, the higher the detected power supply voltage, the smaller the set value, and at the same time, the larger the amount of clothing to be dried, the smaller the set value.

Then, after that, step A6 of the basic configuration
Through steps C7 to C13 similar to steps A7 to A12, in particular, 20 [seconds] at step C9 while the detection value at step C3 is determined to be smaller than the set value at step C7.
Is reached, the filter 2 is set in step C11.
3 is notified that the clogging is clogged.

FIG. 13 shows the relationship between the amount of clothing to be dried and the current of the PTC heater 28 when the filter 23 is clogged.
This indicates that the current of the PTC heater 28 becomes smaller because the wind flow becomes worse. Therefore, it is effective that the set value is made smaller as the amount of the clothes to be dried detected as described above is larger. This allows not only the power supply voltage,
The clogging of the filter can be more accurately determined without being affected by variations in the amount of clothes to be dried.

[0037]

[0038]

[0039]

[0040]

[0041] Figure 17 shows a third embodiment of the present invention, in this one, the microcomputer 29, based on
Steps E1 to E3 similar to steps A1 to A3 of the present configuration
, The reference value and the PT read and stored in step E3
It is determined whether or not the difference from the detected value of the C heater 28 current is equal to or greater than a set value (step E4). Here, the reference value is set in advance based on the fact that a predetermined operation such as a multiplex operation of switches is performed at the time of installation of the clothes dryer, and the PTC heater 28 at that time is operated.
The detected value of the current is used as it, and the written value is written and stored in the non-volatile memory 40, and the written value is read out in step E4, and the detected value of the PTC heater 28 current during normal operation (step E3) is compared with the detected value. It is determined whether or not the difference is equal to or greater than the set value.

Then, after that, step A7 of the basic configuration
Through steps E5 to E10 similar to steps A12 to A12, if it is determined that the difference has reached 20 [seconds] in step E6 while the difference in step E4 is determined to be smaller than the set value, step E7 is executed. It is determined that the filter 23 is clogged and is notified.

In this case, the value written in the non-volatile memory 40 is originally a value corresponding to the power supply voltage in the area of use, and the clogging of the filter 23 is determined based on the value. Needless to detect every time,
Accurate filter 23 not affected by power supply voltage variation
Can be determined.

The drying chamber may be a stationary type, instead of the drum 4, and may be a cabinet that suspends and holds clothes to be dried. In addition, the present invention is not limited to the embodiment described above and shown in the drawings, and can be implemented with appropriate modifications without departing from the scope of the invention.

[0045]

The clothes dryer of the present invention is as described above, and has the following effects. First, the air passing through the drying chamber and the filter is heated by the PTC heater to generate warm air, and the current flowing through the PTC heater when the clothing to be dried is dried in the drying chamber with the warm air is detected.
Compares the set value and the detected value, at which it is determined that the clogging of the filter when the detected value is smaller than the set value, the power supply voltage detecting means for detecting a power supply voltage, the drying chamber
Indirectly or directly detect the speed of the fan that produces the draft
Output speed detection means, and the set value is changed to a value corresponding to the level of the detected power supply voltage and the detected rotation speed based on the detection result. Filter clogging can be determined , and at the same time it is affected by variations in motor speed.
More accurate filter clogging judgment that is not the Ru can.

[0046]

Second , the air passing through the drying chamber and the filter is
Temperature and weathering by heating by TC heater, top Symbol by the hot air
The above PTC heating when drying clothes to be dried in the drying room
The current flowing through the sensor and compare the detected value with the set value.
Comparison, and when the detected value is smaller than the set value,
When the power supply voltage is detected,
Source voltage detecting means, and clothes amount detecting means for detecting the amount of clothes to be dried in the drying room, and the detection results thereof
By changing the set value to a value corresponding to the level of the detected power supply voltage and the detected clothing amount, accurate clogging of the filter which is not affected by variations in the power supply voltage
It is possible to make a judgment, and at the same time, it is possible to make a more accurate judgment of filter clogging which is not affected by variations in the amount of clothes to be dried.

[0048]

Third , the air passing through the drying chamber and the filter is
Current detecting means for detecting a current flowing through the PTC heater, in which the clothing to be dried is dried in the drying chamber by the warm air by heating with a TC heater to generate hot air;
A non-volatile memory, performing a drying operation based on a predetermined operation, writing a value detected by the current detecting unit at that time to the memory, and writing the written value and a value detected by the current detecting unit during normal operation. When the difference is equal to or larger than the set value, it is determined that the filter is clogged. This makes it possible to accurately determine whether the filter is clogged without being affected by variations in the power supply voltage without detecting the power supply voltage one by one. it can.

[Brief description of the drawings]

FIG. 1 is a flowchart for explaining an operation showing a basic configuration .

FIG. 2 is a diagram showing a relationship between a power supply voltage and a set value;

FIG. 3 is a diagram showing a relationship between a power supply voltage and a PTC heater current when a filter is clogged.

FIG. 4 is an overall vertical side view.

FIG. 5 is a schematic electric configuration diagram of the whole;

FIG. 6 is an electric circuit diagram of a voltage detection circuit portion;

FIG. 7 is an electric circuit diagram of a current detection circuit part.

FIG. 8 is a view corresponding to FIG. 1, showing a first embodiment of the present invention;

FIG. 9 is a diagram showing a relationship between a set value and a power supply voltage and a motor rotation speed.

FIG. 10 shows the motor rotation speed and PTC when the filter is clogged.
Diagram showing relationship with heater current

FIG. 11 is a view corresponding to FIG. 1, showing a second embodiment of the present invention.

FIG. 12 is a diagram illustrating a relationship between a power supply voltage, an amount of clothing to be dried, and a set value.

FIG. 13 shows the amount of dry clothes and PT when the filter is clogged.
Diagram showing relationship with C heater current

FIG. 14 is a view corresponding to FIG. 1, showing a third embodiment of the present invention.

[Explanation of symbols]

4 is a drum (drying room), 10 is a fan, 11 is a motor,
25 is a connection duct, 28 is a PTC heater, 29 is a microcomputer (control means), 30 is a power supply, 32 is a voltage detection circuit (power supply voltage detection means), 33 is a current detection circuit (current detection means), 34 is a rotation sensor (rotational speed detecting means), 3 6 electrodes (clothes amount detecting means), 37 detection processing circuit (clothes amount detecting means), 40 denotes a nonvolatile memory.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) D06F 58/28 D06F 58/02

Claims (3)

(57) [Claims] 1. A PTC heater heats air passing through a drying chamber and a filter to generate hot air, and detects a current flowing through the PTC heater when drying clothes to be dried in the drying chamber with the warm air. When the detected value is compared with the set value and the detected value is smaller than the set value and the filter is determined to be clogged, a power supply voltage detecting means for detecting a power supply voltage and a fan for generating air to be passed through the drying chamber are provided. rotation
Rotation speed detection means for indirectly or directly detecting the number , and control means for changing the set value to a value corresponding to the level of the detection power supply voltage and the detection rotation speed from the detection results. A clothes dryer characterized by the following. 2. The air passing through the drying chamber and the filter is subjected to PTC heat.
The air is heated by a heater to generate hot air,
The PTC heater when drying clothes to be dried
Detects the flowing current and compares the detected value with the set value
When the detected value is smaller than the set value, filter clogging
Power supply that detects the power supply voltage.
Pressure detecting means and a garment for detecting an amount of garments to be dried in the drying chamber
With similarity detection means, and based on the detection results
It characterized in that comprises a control means for changing a value corresponding to the level of the detected power supply voltage and detecting garment amount the set value
Clothing dryer. 3. The air passing through the drying chamber and the filter is subjected to PTC heating.
The air is heated by a heater to generate hot air,
Drying the clothes to be dried in the PTC,
Current detection means for detecting a current flowing through the heater;
Memory and dry according to the specified operation
The operation is performed and the current detection means detects the current operation.
Write the value to the memory,
The difference from the value detected by the current detecting means is equal to or greater than a set value.
Control means to determine that the filter is clogged when
Clothing dryer characterized by comprising a.