JPH02255199A - Dryer - Google Patents

Abstract

PURPOSE:To sufficiently sterilize clothes regardless of a clothes quantity and to prevent a temperature from being set excessively high by driving-controlling a heater so that the temperature in a drying chamber may be not lower a prescribed lower limit temperature and not higher an upper limit temperature after a dry degree amounts to a reference value, and stopping a heater driving control when the total time amounts to a prescribed sterilization reference time. CONSTITUTION:After a dry rate detecting signal Vt2 (dry degree) by a dry rate detecting circuit 21 of a dry degree detecting means amounts to a reference value Ka, a heater 7 is driving-controlled so that the temperature in a drying chamber 5 by a temperature sensor 12 may be not lower a lower limit temperature Tl and not higher an upper limit temperature Th. When the total time during which the temperature in the drying chamber 5 is not lower the lower limit temperature Tl amounts to a prescribed sterilization reference time ts, the sterilizing heater driving control is stopped, and a restricted time te is set for the time from the control start for sterilization up to the operation completion. Thus the clothes can be sufficiently sterilized regardless of the clothes quantity, and since the temperature does not become the excessively high value, the damage to the clothes and the dryer can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a dryer that performs sterilization control during drying operation.

(Prior Art) In recent dryers, it has been considered that clothes can be sterilized while drying them at the same time.

However, control for sterilization during drying operation is performed as follows. That is, generally in a dryer,
When the heater and fan motor are energized and drying operation starts, if the clothes contain some moisture, the heat is taken away by evaporation of moisture, so the temperature inside the drying chamber decreases as shown in Figure 5. It rises until a certain point after the start, but
After that, the temperature becomes constant and does not get very high.

In other words, it becomes a constant rate dry state. When this constant rate drying reaches its final stage, the moisture content of the clothing, in other words, the degree of dryness, reaches a predetermined degree of dryness or higher (time point 1+), and the temperature inside the drying chamber increases. Utilizing this feature, control for sterilization is performed when the dryness of the clothes reaches the predetermined dryness. This control is intended to increase the temperature in the drying chamber by continuing to energize the heater for a certain period of time (tk) after the degree of dryness reaches a predetermined degree of dryness.

(Problem to be solved by the invention) However, in the above case, if the amount of clothing is large,
As shown by the broken line in FIG. 5, the inside of the drying chamber may not reach the sterilization temperature, or even if it does, the time to maintain the sterilization temperature state is short, and sufficient sterilization may not be possible. On the other hand, if there is only a small amount of clothing, as shown by the solid line in the same figure, the temperature inside the drying chamber may become excessively high and the time at that high temperature may become longer, causing damage to the fabric. or the dryer itself may be damaged.

The present invention has been made in view of the above circumstances, and its purpose is to provide a dryer that can perform sufficient sterilization regardless of the amount of clothes and does not generate excessively high temperatures. .

[Configuration of the Invention (Means for Solving the Problems) The present invention is designed to perform sterilization control during drying operation, and includes a dryness detection means for detecting the dryness of clothes in a drying chamber. and a temperature sensor for detecting the temperature inside the drying chamber, and after the dryness detected by the dryness detection means reaches a reference value, the temperature inside the drying chamber determined by the temperature sensor becomes equal to or higher than a predetermined lower limit temperature and lower than a predetermined upper limit temperature. a sterilization temperature control means for driving and controlling the heater so that the temperature control means for sterilization stops the heater drive control by the sterilization temperature control means when the total time during which the inside of the drying chamber has reached the lower limit temperature or more reaches a predetermined sterilization reference time; It is characterized in that it is equipped with a sterilization time control means.

(Function) Whether or not the drying operation has reached the end of constant rate drying can be determined by whether or not the degree of dryness measured by the degree of dryness detection means has reached the standard value, and from this point on, temperature control is possible. be. The sterilization temperature control means operates the heater so that after the degree of dryness determined by the degree of dryness detection means reaches the reference value, the temperature in the drying chamber determined by the temperature sensor becomes equal to or higher than a predetermined lower limit temperature and equal to or lower than a specified upper limit temperature. Since the drive is controlled, the temperature inside the drying chamber can be raised to the sterilization temperature regardless of the amount of clothes. In this case, when the temperature reaches the upper limit, the temperature is controlled to be below that temperature, so that while the necessary sterilization temperature is maintained, the temperature of the drying chamber, and by extension the dryer itself, does not become excessively high. Furthermore, sterilization cannot be said to be sufficient unless the sterilization temperature and the total time above the sterilization temperature are satisfied to a certain extent, and conversely, if the total time is too long, fabric damage etc. will occur. However, in the means of the present invention, the sterilization time control means stops the heater drive control by the sterilization temperature control means when the total time during which the inside of the drying chamber has reached the lower limit temperature or more reaches a predetermined sterilization reference time. As a result, there is no excess or deficiency in the total amount of time the cloth is kept at a temperature above the sterilization temperature, and good sterilization can be achieved, as well as damage to the cloth can be prevented.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

First, in FIG. 2 showing the overall structure of the dryer, 1 is an outer box, 2 is a drum rotatably disposed inside this outer box 1, and the front opening edge 2a of this drum 2 is connected to the outer box 1. The fan casing 4 supports the fan casing 4 at its rear opening edge 2b. The inside of this drum 2 is configured as a drying chamber 5. Reference numeral 6 denotes a double-winged fan provided inside the fan casing 4 so as to partition the fan casing 4 into front and rear parts, and this fan 6 also serves as a heat exchanger. Reference numeral 7 denotes a heater disposed in the lower portion of the fan casing 4 at the vent 4a portion. The drum 2 and fan 6
is rotated by a motor 8, and in this case, the air in the drying chamber 5 is passed through the filter 9 and the exhaust port 4b.
The air is sucked into the front part of the fan casing 4 through the fan casing 4, heated by the heater 7, and returned to the drying chamber 5, which is repeated. At the same time, outside air is sucked in through the outside air intake port ]a, exchanges heat with the air in the drying chamber 5 exhausted from the exhaust port 4b, and is discharged outside the machine from the outside air outlet 1b. ing.

Reference numeral 10 denotes a pair of electrodes, which are mounted on the front surface of the lower part of the fan casing 4 (-1 plate 11 interposed therebetween) so that the objects to be dried (clothes) housed in the drying chamber 5 can come into contact with them. .

A sensor 12 is a temperature detecting means for detecting the temperature inside the drying chamber 5, and is disposed at the exhaust port 4b.

Next, in FIG. 1 showing the electrical configuration, numeral 13 is a microcomputer which is an operation control device, which controls the drying operation and also functions as sterilization temperature control means and sterilization time control means. 14 is a course changeover switch for selecting an "iron" course, a "timer select time" course, a "standard" course, etc., and ]5 is a start switch that also serves as a stop. Reference numeral 16 denotes a display made of a light emitting diode or the like, which displays the course selected by the course changeover switch 14. Reference numeral 17 denotes a clock pulse generation circuit, which provides clock pulses Ij to the microcomputer 13.

One end of the electrode 10 is connected to a DC power supply terminal 18, and the other end is grounded via a resistor 19. 20 is a contact rate detection circuit for detecting the load amount of the material to be dried;
In this case, the electrode 10 detects the contact rate of the dry object by receiving an electric signal output according to the cloth resistance of the dry object, and uses the contact rate as the load amount detection signal Vt1 to the microcomputer 1.
Give to 3. Since the electrode 10 outputs an electric signal according to the resistance of the cloth, the contact ratio detection circuit 20 detects the wetness as well as the amount of the material to be dried, thereby detecting the overall drying load amount. Reference numeral 21 denotes a drying rate detection circuit serving as a dryness detecting means, which receives an electrical signal from the electrode 10 (proportional to the humidity), detects the drying rate of the object to be dried, which is inversely proportional to the electrical signal, and detects the drying rate The resulting drying rate detection signal Vt2
(The detection signal t2 indicates an output level proportional to the degree of dryness of the clothes) is given to the microcomputer 13.

Note that 22 is a drive circuit for driving the motor 8 and heater 7;
23 is a DC power supply circuit that serves as a power source for the microcomputer 3, and 24 is a power switch.

Next, the operation of the above configuration will be explained with reference to the functions of the microcomputer 13 as well as FIGS. 3 and 4.

FIG. 3 shows the contents of the control program held by the microcomputer 13. This microcomputer 13 presets a reference value Ka (drying rate 85 to 90%) for dryness for determining the end time of constant rate drying, and also sets an upper limit for temperature control during normal operation. Temperature Ta (e.g. 72°C) and - upper limit temperature Tb (e.g. 57°C)
℃), furthermore, the upper limit temperature Th (e.g. 85°C) and lower limit temperature TΩ (e.g. 80°C) for temperature control regarding sterilization are set, and the sterilization reference time ts is also set.
(for example, 5 minutes) and the driving limit time te (for example, 35 minutes) are set in advance. Further, FIG. 4 shows an example of temperature changes within the drying chamber 5.

Now, when the start switch 15 is operated to start the drying operation, as shown in step S1, the motor 8 and the heater 7 are energized, thereby supplying warm air into the drying chamber 5 and drying the clothes. It is being dried. In this case, as can be seen from FIG. 4, the temperature inside the drying chamber 5 rises at the beginning of the operation, but then becomes constant, that is, a constant rate drying state.

At the end of this constant rate drying, the drying rate is 8.
When the drying rate reaches 5 to 90%, the drying rate reaches the reference value Ka mentioned above, which is detected by the microcomputer 3 (step S2). The microcomputer 13 thus executes the control for sterilization described below. That is, first, the upper limit temperature and lower limit temperature for temperature control are set to Th and TΩ, respectively (step 8.3).

Then, in step S4, at this point (time 1+ in FIG. 4)
Count the time since (the count time is tc). In the next step S5, it is determined whether the elapsed time tc from this time t has exceeded the driving limit time te. At this point, the elapsed time tc has not exceeded the operation limit time te, so the process moves to step S6 and the upper and lower limit temperatures set at this point are Th and Tj.
7 or not. In this case, since the upper and lower temperature limits are Th and TΩ, the process moves to step S7. In this step S7, it is determined whether the temperature inside the drying chamber 5 measured by the temperature sensor 12 is equal to or higher than the lower limit temperature 19, and if it is not higher than the lower limit temperature, the process returns to step S4. At this point, the temperature inside the drying chamber 5 has not reached the lower limit temperature Tρ (80°C), so
Returning to step S4, step S4. Step S5.
Step S6. Step S7. It enters a standby state in the loop of step S4. Since the heater 7 remains energized, the temperature inside the drying chamber 5 is at the time t in FIG.
and when it exceeds the lower limit temperature TjQ (time t2), the microcomputer 13 performs step S.
7, the process moves to step S8, where the total time is set as tc2), and then the process moves to step S9. In this step S9, the inside of the drying chamber 5 is at the lower limit temperature t4.
The total time tc2 of 7 or more is the sterilization reference time ts
Determine whether it has been reached. Since it has not reached the upper limit temperature Th at this point, the process moves to step SIO to determine whether or not the temperature inside the drying chamber 5 has reached the upper limit temperature Th, and since it has not reached the upper limit temperature Th at this point, the process returns to step S4. After this, when the temperature inside the drying chamber 5 further increases, it reaches the upper limit temperature Th.
The microcomputer 13 turns off the heater 7 (step 511). As a result, the temperature inside the drying chamber 5 decreases, but when it falls below the lower limit temperature TJ7 (step S1-2
), the heater 7 is reenergized (step 813).
. In this way, the temperature inside the drying chamber 5 reaches the lower limit temperature Tj! The heater 7 is controlled so that the temperature is above and below the upper limit temperature. Then, while the inside of the drying chamber 5 is at or above the lower limit temperature T, Q, the time is totaled.

After that, when the total time tC2 reaches the sterilization reference time tS (time t), the microcomputer 13 sets the temperature settings to the upper limit temperature Ta and lower limit temperature Tb of normal operation (step 514), and proceeds to step S4. return. In this case, it is determined in step S5 that the set temperature at this point is not the upper limit temperature Th and lower limit temperature Te for sterilization, so as can be seen from steps S15 to S19, the upper limit temperature Ta and the lower limit temperature T for normal operation are determined.
Based on b, the heater 7 is turned on and off, and the temperature is controlled. After this, when the driving limit time te has elapsed (time t4
), the heater 7 is cut off (step 520), and only the ventilation operation based on the drive of the motor 8 is performed for 5 minutes (step 521).1 Afterwards, the motor 8 is cut off (step 522), and the drying operation is terminated (time ts).

According to the present embodiment described above, after the drying rate detection signal Vt (dryness) by the drying rate detection circuit 21 serving as the dryness detecting means reaches the reference value Ka, that is, the drying operation reaches the end of constant rate drying. Thereafter, the heater 7 is driven and controlled so that the temperature inside the drying chamber 5 measured by the temperature sensor 12 is higher than the predetermined lower limit temperature T1 and lower than the upper limit temperature Th, so that the temperature inside the drying chamber 5 can be sterilized regardless of the amount of clothes. The temperature can be increased. In this case, when the upper limit temperature Th is reached, the temperature is controlled to be below the upper limit temperature Th, so that while the necessary sterilization temperature Tρ is maintained, the temperature inside the drying chamber 5, and by extension the dryer itself, does not become excessively high.

By the way, sterilization cannot be said to be sufficient unless the lower limit temperatures T and Q, which are the sterilization temperatures, and the total time at which the sterilization temperature is 19 or higher are satisfied to a certain extent, and conversely, if the above-mentioned total time is too long, fabric damage etc. will occur. .

However, in this embodiment, the temperature inside the drying chamber 5 is lower than the lower limit temperature 1.
Since the heater drive control for sterilization is stopped when the total time of 9 or more reaches the predetermined sterilization reference time ts, there is no excess or deficiency in the total time of the temperature state above the sterilization temperature. In other words, the sterilization time can be kept to the minimum necessary, so that not only good sterilization can be achieved, but also damage to the cloth can be prevented.

Further, in the above embodiment, after the temperature control and time control for sterilization are performed, normal temperature control is returned to, which is more effective in preventing fabric damage.

In addition, in the above embodiment, the purpose of setting a time limit te for the time from the start of control for sterilization to the end of operation is to take into account thermal deterioration of each part, etc., so that operation will not be unnecessarily prolonged. This is for the purpose of Of course, this time limit te is set to a time that allows sufficient control for sterilization unless there is some kind of abnormality.

Note that the present invention is not limited to the above embodiments,
Various modifications may be made without departing from the spirit of the invention.

[Effects of the Invention] As is clear from the above description, the present invention is designed to perform sterilization control during drying operation, and includes a dryness detection method for detecting the dryness of clothes in a drying chamber. means, a temperature sensor for detecting the temperature inside the drying chamber, and after the degree of dryness measured by the dryness detection means reaches a recommended value, the temperature inside the drying chamber measured by the temperature sensor is equal to or higher than a predetermined lower limit temperature and lower than a predetermined upper limit temperature. a sterilizing temperature control means for driving and controlling the heater so that the sterilizing temperature control means controls the heater drive so that the temperature within the drying chamber reaches a predetermined sterilization reference time when the temperature within the drying chamber reaches or exceeds the lower limit temperature; and a sterilization time control means to stop the sterilization.
Figure 1 is a block diagram of the electrical configuration, Figure 2 is a longitudinal side view of the whole, Figure 3 is a flowchart showing control details, and Figure 4 is a diagram showing an example of temperature change. FIG. 5 is a diagram corresponding to FIG. 4 showing a conventional example.

In the figure, 5 is a drying chamber, 7 is a heater, 8 is a motor, 12 is a temperature sensor, 13 is a microcomputer (temperature control means for sterilization, time control means for sterilization), and 21 is a drying rate detection circuit (dryness detection means). ).

Applicant: Toshiba Co., Ltd. 11

Claims (1)

[Claims] 1. A device that performs sterilization control during drying operation, and includes a dryness detection means for detecting the degree of dryness of clothes in the drying chamber, a temperature sensor for detecting the temperature in the drying chamber, and sterilizing temperature control means for driving and controlling a heater so that the temperature within the drying chamber measured by the temperature sensor becomes equal to or higher than a predetermined lower limit temperature and lower than a predetermined upper limit temperature after the degree of dryness determined by the temperature detection means reaches a reference value; sterilization time control means for stopping heater drive control by the sterilization temperature control means when the total time during which the temperature has exceeded the lower limit temperature reaches a predetermined sterilization reference time.