JPH034240B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a system for drying clothes in the drum by feeding heated air obtained from a heater into a rotating drum serving as a drying chamber, and then The present invention relates to a method of controlling the operation of a clothes dryer that discharges heated air from a rotating drum.

[Conventional technology]

An example of the overall structure of such a clothes dryer is shown in Section 5.
To explain the figure, 1 is an outer box which has a door 2 for entering and exiting clothes to be dried and an operation panel 5 in the center of the front, and a motor 3 and a drum 4 rotated by the motor 3 are housed in the outer box 1. Heaters 6a and 6b are disposed in the front opening of.

A fan case 7 is formed behind the drum 4,
Double wing fan 8 with a heat exchanger in the case etc.
are arranged, and the double wing fan 8 and the heater 6a,
6b, a circulation path 9 was formed between the two. In addition, 1 in the figure
0 indicates a drainage hose that leads dehumidified water to the outside of the machine, 11 indicates a cooling air intake port, and 12 indicates a cooling air discharge port.

In this way, the door 2 is opened, the clothes to be dried are put into the drum 4, and the air is supplied to the heaters 6a and 6b via the circulation path 9 by the double-wing fan 8,
Here, it is heated and sent as hot air into the drum 4 to warm the damp clothes to be dried and evaporate the moisture.

This heated air containing moisture is sucked into the fan 8 on both sides, where it is cooled and dehumidified by the cooling air taken in from the intake port 11, and is returned to the heater 6a, 6b, heated, and sent into the drum 4. Further, the dehumidified water is discharged to the outside of the machine via the drainage hose 10.

By the way, the end of the drying operation is determined by disposing a dryness measurement sensor 14 inside the fan case 7, detecting that the heating operation time has reached a preset time, and then stopping the exhaust air from the drum 4. temperature,
The temperature rises once during the material preheating period immediately after the start of operation, stabilizes during the subsequent constant rate drying period, and then further rises during the decreasing rate drying period, when the temperature rise is detected and the temperature is detected based on the output from the drying measurement sensor 14. It's in control.

As shown in FIG. 6, this control circuit introduces output signals from various control switches 16 housed in the operation panel 5 to a control device 15 using a microcomputer, etc., and also inputs output signals from the dryness measurement sensor 14. A detection signal from a drying completion detection circuit 17 to which an output signal is input is introduced, and an output signal from this control device 15 is introduced into triacs 18a and 18b as switching elements for controlling on/off of heaters 6a and 6b. Ru. In the figure, 24 is a thermostat for controlling the heaters 6a and 6b on and off in order to keep the temperature inside the drum 4 at a set temperature, and 13 is a power source.

In this way, the strength and dryness of the heaters 6a and 6b are set in advance by the control switch 16 before the start of operation, and after the start of operation, the dryness measuring sensor 14
When the controller 15 determines that the drying is completed based on the detection signal from the drying end detection circuit 17, the output from the controller 15 activates the heaters 6a and 6.
The power supply to motor 3 and motor 3 is cut off, and the operation ends.

By the way, if for some reason the drying completion detection circuit 17 does not operate despite receiving the output from the dryness measurement sensor 14, or if the inside of the drum 4 becomes abnormally high temperature due to other factors, , the temperature around the thermostat 24 also rises, so when this temperature reaches the set value, this is detected and the thermostat 24 is turned off, and the heater 6 is turned off.
The power supply to a and 6b is cut off to prevent the inside of the drum 4 from becoming any more abnormally high temperature.

[Problem that the invention seeks to solve]

Conventionally, the thermostat 24 is used to prevent the inside of the drum 4 from becoming abnormally hot and becoming dangerous, but for example, the heater 6a,
If the energization to heater 6b is set to "weak" for only one heater 6a or 6b, or if the ambient temperature (room temperature) is low, the exhaust temperature will not rise sufficiently and the dryness measurement sensor 14 will indicate the termination. Detection signal is not output. At the same time, the thermostat 24 turns off the drum 4 just before the set temperature.
Since the internal temperature stops rising, the heaters 6a and 6b
Electricity continues to be applied to the unit, and operation continues indefinitely at this temperature.

As a result, inside drum 4, thermostat 24
The high temperature state at the temperature just before turning off continued for a long time, causing damage to clothes due to over-drying, shortening the lifespan of the equipment, and wasting electricity.

In this case, since the thermostat 24 has only one mechanical contact, it is difficult to change the operating temperature depending on conditions such as the ambient temperature.

The purpose of the present invention is to eliminate the disadvantages of the conventional example,
A method for controlling the operation of a clothes dryer that ensures safe drying operation by preventing the heater output from being turned off due to the strength of the heater output or the ambient temperature, and by preventing the high temperature state in the drying chamber from continuing longer than necessary. It is about providing.

[Means for solving problems]

In order to achieve the above object, the present invention provides a clothes dryer in which heated air obtained from a heater is sent into a drying chamber to dry clothes, and then the heated air is discharged from the drying chamber. The measured value of the ambient temperature based on the output signal of the heater and the command signal from the switch that determines the strength of the heater output are input to the control device. is set in advance, measured by a sensor for measuring the temperature in the drying room, and the control device detects that the exhaust temperature from the drying room, which is input from the sensor to the control device, has reached this set temperature value and turns on electricity to the heater. The gist of this is to turn it off.

[Effect]

According to the present invention, the maximum temperature of the drying chamber is set in advance based on the ambient temperature and the strength of the heater output, and when the exhaust temperature from the drying chamber reaches this set value, the heater is automatically turned on. Since the heater output is turned off, the temperature at which the heater output is turned off can be variably set according to the temperature in the drying chamber, which varies depending on the ambient temperature and the strength of the heater output. High temperature conditions do not continue for longer than necessary.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

Fig. 1 is a heater output control circuit diagram used in the method for controlling the operation of a clothes dryer according to the present invention, and Fig. 2 is a vertical side view showing a clothes dryer in which the method of the present invention is carried out, and shows the basic configuration of the clothes dryer. Since this is the same as that already explained with respect to the conventional example shown in FIG. 5, the same components are given the same reference numerals and detailed description thereof will be omitted.

In the method of the present invention, the dryness measurement sensor 14 is disposed in the fan case 7 of the fan 8 on both sides as in the conventional method, but in addition to this, a sensor for measuring the temperature inside the drum 4 serving as the drying chamber is used to measure the temperature in the drying room. The thermistor 19 is connected to the dryness measurement sensor 1.
In addition, an ambient temperature measuring thermistor 20 was provided near the air intake port 11 as a sensor for measuring the room temperature.

Next, the control circuit for the heater output which is controlled by the outputs from the thermistor 19 for measuring the temperature in the drying room and the thermistor 20 for measuring the ambient temperature will be explained with reference to FIG. from the ambient temperature measuring circuit 23 which measures the ambient temperature (room temperature) using the output signal from the drying room temperature measuring circuit 22 which measures the temperature inside the drum 4 based on its exhaust temperature, and the output signal from the ambient temperature measuring thermistor 20. The output signal from the control switch 16, the command signal that determines the strength of the heater output depending on whether it is turned on or off, and the number of devices that are turned on, and the output signal from the drying end detection circuit 17 are introduced into the control device 15, and the control device 15 Control signals from the heaters 6a and 6b were introduced to the heaters 6a and 6b via triaxes 18a and 18b.

In this embodiment, the thermistors 19 and 20 are used as means for changing the conduction rate depending on the measured values of the exhaust gas temperature and the ambient temperature, but it is also possible to replace these with thermocouples or other elements. Also, relays or the like may be used in place of the triaxes 18a and 18b as long as they work as switching elements.

Next, the usage and operation will be explained according to the flowchart in Figure 4. To dry clothes,
In the same manner as before, first open the door 2, put the clothes to be dried into the drum 4 (step-puy), close the door 2,
The control switch 16 in the operation panel 5 is used to input the intensity settings for which heaters 6a and 6b to turn on and the degree of drying finish (step C).

In response to the output from the control switch 16, the control device 15 energizes both heaters 6a and 6b via the triaxes 18a and 18b when the heater is set to strong, and energizes either of the heaters when the heater is set to weak. One heater 6a or 6b
energize only (steps, steps, steps).

On the other hand, based on the output signal from the ambient temperature measuring thermistor 20, the ambient temperature measuring circuit 23
The ambient temperature at the start of operation is measured (step 2), and this measured value is input to the control device 15.

The control device 15 determines and sets the maximum temperature within the drum 4 at which the output of the heaters 6a, 6b is turned off based on this input measurement value and the setting of either the strength or weakness of the heaters 6a, 6b (step).
As shown in FIG. 3, this set temperature value is higher when the heater is strong than when the heater is weak, and increases as the ambient temperature rises.

Then, motor 3 is also energized (step),
When the drying operation starts and progresses, the degree of dryness is detected by the drying end detection circuit 17 based on the output from the dryness measuring sensor 14, and the fact that the drying state set by the control switch 16 has been reached is outputted to the control device 15. Then, the control device 15 determines that the drying is completed (Step 2), and the output from the controller 15 turns on the heaters 6a,
6b is turned off (step), the motor 3 is stopped (step), and the drying operation is completed (step).

By the way, while the drying operation is in progress,
When the heaters 6a and 6b are on (stepper), the drying room temperature measuring circuit 22 is activated based on the output signal from the drying room temperature measuring thermistor 19.
When the temperature in the drying room measured by reaches the maximum value set at the start of operation (step), the control device 15 cuts off the power to the heaters 6a and 6b (step), regardless of the degree of drying.
To prevent the temperature inside the drum 4 from becoming any higher.

Thereafter, when the heaters 6a and 6b are turned off as described above and the temperature inside the drum 4 falls below the set temperature (step), the heaters 6a and 6b are energized again (step).
The drying operation is restarted and continues until a completion signal is output from the drying completion detection circuit 17.

In the above embodiment, the ambient temperature was measured at the start of operation, but the measurement is not limited to this. The set temperature may be changed as appropriate.

Further, as shown in FIG. 3, the set temperature value does not necessarily have to be increased linearly in response to the ambient temperature, but can be increased in a curved manner if the same effect can be obtained.

Further, in this embodiment, the case where the heater output is divided into two types, strong and weak, has been described as an example, but the heater output amount is not limited to this as long as it can be set to a plurality of values. It is also conceivable to set the maximum temperature at which the heater is turned off only in response to a limited amount of heater output.
Furthermore, in addition to turning off the heater output when the set temperature is reached, the drying operation may be terminated at this point.

〔Effect of the invention〕

As described above, in the clothes dryer operation control method of the present invention, the maximum temperature inside the drum for turning off the heater output is set by taking into consideration the ambient temperature and the strength of the heater output in advance. It can flexibly handle the temperature inside the drum, which varies depending on conditions such as the strength of the heater output, especially when the ambient temperature is low.
When the heater is weak, it is possible to prevent the high temperature state inside the drum from continuing for an abnormally long time, thereby ensuring operational safety. Further, since a thermostat that mechanically determines only one contact point is not used as in the prior art, the setting of the maximum temperature can be variably set as desired.

[Brief explanation of the drawing]

FIG. 1 is a heater output control circuit diagram used in the method of controlling the operation of a clothes dryer according to the present invention, and FIG. 2 is a longitudinal side view showing a clothes dryer in which the method of the present invention is carried out.
Figure 3 is a characteristic curve diagram showing the set temperature at which the heater output is turned off, Figure 4 is a flowchart showing the operation, Figure 5 is a longitudinal side view showing a conventional example of a clothes dryer, and Figure 6 is the same heater output. It is a control circuit diagram. 1...Outer box, 2...Door, 3...Motor, 4...
Drum, 5...Operation panel, 6a, 6b...Heater, 7...Fan case, 8...Double wing fan,
9...Circulation path, 10...Drainage hose, 11...Intake port, 12...Exhaust port, 13...Power supply, 14...
Dryness measurement sensor, 15...Control device, 16...
...Control switch, 17...Drying end detection circuit, 1
8a, 18b... triax, 19... thermistor for measuring temperature in the drying room, 20... thermistor for measuring ambient temperature, 22... circuit for measuring temperature in the drying room,
23...Ambient temperature measurement circuit, 24...Thermostat.

Claims (1)

[Claims] 1. In a clothes dryer that blows heated air obtained from a heater into a drying chamber to dry clothes and then exhausts the heated air from the drying chamber, measuring the ambient temperature based on an output signal from an ambient temperature measurement sensor. The value and the command signal from the switch that determines the strength of the heater output are input to the control device, and this control device presets the maximum value of the drying room temperature based on the ambient temperature and the strength of the heater output, and sets the maximum value for the drying room temperature measurement. A clothes dryer characterized in that the control device detects that the exhaust temperature from the drying chamber, which is measured by a sensor and inputted to the control device from the sensor, has reached the set temperature value and turns off the power to the heater. operation control method.