JPS59155293A - Clothes dryer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a clothes dryer that can prevent deterioration of clothes during drying and shorten the time required for drying.

Conventionally, this type of clothes dryer was manufactured by Japanese Patent Laid-Open No. 53-275.
The one shown in Publication No. 7 is known.

FIG. 1 is a sectional view of the clothes dryer disclosed in this publication. In FIG. 1, 1 is an outer box, 2 is a drum rotatably supported inside the outer box, and the drum is connected to a drum belt 5.
It is rotationally driven by a motor 4 via. Reference numeral 5 denotes a heater, which heats the air flowing in from the intake lower provided on the back plate 6 of the outer box 1. This heated air is transferred to the drum 2
It is designed to flow inward. Reference numeral 8 denotes an exhaust and air passage provided at the rear of the drum 2, and a fan 9 is installed inside the drum 2, and the fan is configured to be rotationally driven by the motor 4 via a fan belt 10. 11 is an exhaust port of the exhaust air passage 8; 12 is a door for taking clothes into and out of the drum 2; and 16 is a lint filter for collecting lint generated during drying.

Next, the operation of the clothes dryer explained in FIG.
This will be explained using the characteristic diagram shown in the figure. First, open door 12,
Put the clothing i into the drum 2 and close the door 12. Thereafter, a timer (not shown) is operated to supply power supply current to the motor 4 and heater 5 for a predetermined period of time. As a result, motor 4
is rotated, and the drum 2 and fan 9 are rotated via the belts 3 and 10. As the fan rotates, air is sucked in from the intake lower, and after being heated by the heater 5, it is sent into the drum 2, where it comes into contact with the clothes in the drum and removes moisture from the clothes. Evaporate. This evaporated air containing moisture passes through the exhaust filter 16, passes through the exhaust air passage 8, and is discharged from the exhaust port 11 to the outside of the outer box 1.

Clothes are dried in this way, and the exhaust air temperature and the temperature of the clothes with respect to the drying time are as shown in FIG. 2. That is, the heat from the heater 5 supplied into the drum 2 is used to raise the temperature of the moisture contained in the clothes immediately after drying starts, and is used for a while after the temperature of the clothes reaches a certain level. is used only to evaporate moisture from clothing. This period is called the dry period, in which heat is used as latent heat, so the exhaust air temperature and the temperature of clothing are low. Eventually, the moisture content in clothing decreases, and when it reaches a point called the critical moisture content and enters a period called the lapse rate drying period, the rate of movement of moisture from inside the clothing becomes faster than the rate of evaporation on the surface. It slows down, dry spots appear on the surface of clothing,
Since the heat is dissipated as a thermosensor, the exhaust temperature and the temperature of the clothes rise rapidly.

Conventional devices are configured as described above, so they have the disadvantage that the temperature of the clothes increases rapidly during lapse rate drying, and the high temperature deteriorates the clothes. Therefore, even if an attempt was made to increase the power supplied to the heater, the maximum temperature during the lapse rate drying period had to be lower than the limit temperature of the clothing, making it impossible to significantly shorten the drying time.

This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and detects the drying state of clothes to be dried, and when it is detected that the drying period has entered the lapse rate drying period. To provide a clothes dryer which reduces power supply to a heater, thereby making it possible to dry clothes in a short time without deteriorating the clothes.

An embodiment of the present invention will be described below with reference to the drawings. 6th
In the figure, numerals 1 to 16 are the same as in FIG. Reference numeral 14 denotes an exhaust temperature detector such as a thermistor installed in the exhaust air passage 8, and 15 denotes an intake air temperature detector provided in the intake air passage 16. The control device in the clothes dryer shown in FIG. 6 is constructed as shown in FIG. 4. In FIG. 4, the same reference numerals as in FIG. 6 indicate the same elements. Reference numeral 17 denotes a temperature difference detection section to which temperature signals from the exhaust temperature detector 14 and the intake air temperature detector 15 are input, and detects a temperature difference based on these temperature signals. 18 compares the output of the temperature difference detection section with a preset temperature set to a predetermined temperature to determine whether the clothes are in the drying period or in the drying period, and depending on the result, the heater This is a comparison section that controls 5.

Next, the operation of the clothes dryer described above with reference to FIGS. 6 and 4 will be explained using the characteristic diagrams of FIGS. 5 and 6. Clothes are placed in the drum 2 in the same manner as in the conventional example.
The motor 4 and the heater 5 are supplied with electric power to send air heated by the heater 5 to the clothes in the drum 2. As a result, the clothes undergo a preheating period and then enter the drying period described above. During this dry period, the heat from the heater 5 is used as latent heat, so the temperature difference detection unit 1
The difference between the exhaust gas temperature and the intake air temperature detected at step 7 is constant. When the critical moisture content is exceeded, the heat from the heater 5 is used as a thermosensor, so the exhaust gas temperature rises rapidly, and therefore the difference between the intake air temperature and the exhaust air temperature also rises rapidly. When this temperature difference becomes larger than the set temperature, the comparing section 8 determines that the decreasing rate drying period has entered, and the power supplied to the heater 5 is reduced.

Figure 5 is a characteristic diagram showing the temperature of clothes with respect to the drying time in a clothes dryer.The temperature of the clothes becomes almost constant during the drying period after the preheating period, and then passes the critical moisture content and enters the lapse rate drying period. Once inside, the temperature of clothing has been shown to rise rapidly.

The broken line T1 is based on the conventional device, and the temperature of the clothes during the lapse rate drying period becomes very high. However, as in the dryer shown in FIGS. By reducing the temperature, the temperature of the clothing during the lapse rate drying period is limited as shown by the solid line T2 in FIG. 5, and it is possible to prevent the clothing from deteriorating due to heat.

In order to prevent clothing from deteriorating due to heat, the power supplied to the heater 5 has conventionally been determined so that the temperature of the clothing does not exceed a limit temperature T6, as shown by the broken line T in FIG. Therefore, when the power supplied to the heater 5 is increased in order to shorten the drying time of the clothes, the temperature of the clothes during the lapse rate drying period exceeds the limit temperature T, as shown by the broken line T3. On the other hand, in this embodiment, as shown at T4, when the power supplied to the heater 5 is increased in order to shorten the drying time of the clothes, the temperature of the clothes increases during the drying period and the critical water content is increased. However, when the drying period reaches the decreasing rate, the power supplied to the heater 5 is limited by the comparing section 18, so the temperature of the clothes is lower than the limit temperature T. Therefore, there is no deterioration of clothes due to high temperatures, and drying time can be shortened.

In the above embodiment, the drying state of the clothes to be dried is detected based on the temperature difference between the exhaust air temperature and the intake air temperature, but this detection means is not limited to this, for example, a drum. Detection may also be made by contact between an electrode provided inside the drying material and a change in the humidity of the exhausted air, etc. In short, it is detected that the material to be dried has entered the decreasing rate drying period. Good to have.

Further, in the above embodiments, an exhaust type clothes dryer has been described, but even a circulation type clothes dryer can produce similar effects.

As described above, this invention controls the heat generation of the heater according to the drying state of the clothes to be dried, so the clothes do not deteriorate due to high temperatures, and the power supply to the heater can be increased. This allows the drying time to be shortened without deteriorating the clothes.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional clothes dryer, and Figure 2 is a cross-sectional view of a conventional clothes dryer.
FIG. 6 is a sectional view of a clothes dryer showing an embodiment of the present invention; FIG.
A block diagram showing the control device of the one shown in FIGS. 5 and 6.
This figure is a temperature characteristic diagram for explaining the operation of the one shown in FIG. 2 drum, 4: motor, 5: heater, 9: fan, 1
4: Exhaust temperature detector, 15: Intake temperature detector, 17: Temperature difference detection section, 18: Comparison section. Agent Makoto Kuzuno - 1st Hi 2nd figure ρ Senmon - ←, 1 binding! Lake -←Liaojiao Tang period- Figure 3

Claims (1)

[Claims] A clothes dryer configured to dry clothes by supplying hot air into a drum containing clothes to be dried,
A clothes dryer comprising means for detecting a dry state of clothes, and controlling heat generation of a drying heater according to the dry state detected by the means.