JPH0549315B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a clothes dryer used in general households that has a function of detecting the drying state of items to be dried.

Conventional Structure and its Problems Conventionally, in this type of clothes dryer, the structure shown in FIG. 1 has been common.

In FIG. 1, 1 is the main body of the dryer, 2 is a rotary drum rotatably provided in the main body 1 of the dryer and driven by a motor 3, 4 is a clothes slot provided on the front of the main body 1, and 5 is a rotary drum. A heater that heats the air blown into the drum 2, 6 is the rotating drum 2
A fan that introduces hot air into the interior, 7 is a rotating drum 2
8 is the drum front plate 7 which pivotally supports the drum at the front.
9 is a fan case, and 10 is a temperature sensing portion formed inside the fan case 9. The magnitude of the electrical resistance when the object to be dried comes into contact with the electrode 8 is determined, and the temperature rise from the moment when the drying progresses and the electrical resistance increases to a certain value is detected by the temperature sensor 10, and the drying process is started. Automatically control the termination of

However, with this configuration, when drying an object with a small capacity, the temperature rises rapidly over time, so there is a problem that the end of drying may be erroneously controlled even though the drying is not sufficient. .

OBJECTS OF THE INVENTION The present invention solves these conventional problems and provides a clothes dryer that can properly detect dryness even when the volume of the items to be dried is small.

Composition of the Invention In order to achieve the above object, the clothes dryer of the present invention includes: a heater serving as a heat source; a rotating drum that rotates and stirs the material to be dried; and a fan that introduces hot air from the heater into the rotating drum. A fan case surrounding the fan and arranged behind the rotating drum, and a first fan case provided inside the fan case.
a temperature-sensing section; a drum front plate that pivotally supports the rotating drum in front and has a hot air outlet; an electrode that contacts the drying material in the rotating drum to detect the drying rate; A second temperature-sensing part is installed on the inner wall apart from the hot air outlet, and when a predetermined drying rate is detected by the electrode,
The temperature difference between the first temperature sensing section and the second temperature sensing section is detected, the amount of material to be dried is determined based on this temperature difference, and the subsequent drying operation time is controlled.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings.

In FIG. 2, 11 is the dryer main body, 12 is rotatably provided in the dryer main body 11, and a motor 1
3 is a rotating drum driven by 14, the main body 11
15 is a heater that heats the air blown into the rotating drum 12;
16 is a drum front plate that pivotally supports the rotating drum 12 in front; 18 is an electrode formed on the drum front plate 17;
9 is a fan case, 20 is a first temperature sensing section formed inside the fan case 19, and 21 is a second temperature sensing section formed inside the drum front plate 17.

In the above configuration, when drying a small volume of material to be dried, the air coming out of the heater 15 flows toward the fan 16 along the path shown in A, and the air flows through the drum front plate 1.
Heat is difficult to transfer to the vicinity of the second temperature sensing portion 21 formed within the second temperature sensing portion 7 . When the volume of the material to be dried is large, the airflow becomes as shown in (b), and the temperature near the second temperature sensing section 21 also becomes high. FIG. 3 shows the temperature change when a small volume of the material to be dried is dried, and FIG. 4 shows the temperature change when the volume of the material to be dried is large. In FIGS. 3 and 4, the solid line indicates the temperature change of the first temperature sensing section 20.
t ₁ , the broken line indicates the temperature change t ₂ of the second temperature sensing section 21 .
Further, it is assumed that dryness detection is performed by the electrode 18 at times a and a'. That is, it is assumed that the electrical resistance of the object to be dried in contact with the electrode 18 has increased to a certain value. By measuring the value ΔT of t ₁ −t ₂ at that time and comparing it with the set value, it can be determined that the volume of the material to be dried is small. In that case, the appropriate end of the process is controlled by lengthening the delay time after the dryness is detected by the electrodes 18. Alternatively, the rotation speed of the rotary drum 12 may be reduced to perform stirring suitable for a small volume. FIG. 5 shows a flowchart of the above embodiment. In the above embodiment, an example was shown in which the first temperature sensing section 20 was formed inside the fan case 19 and the second temperature sensing section 21 was formed inside the drum front plate 17, but the first temperature sensing section 2
0 is a place that is constantly exposed to hot air, and the second temperature sensing part 2
1 may be formed in the rotary drum 12 at a location where hot air is difficult to reach when the volume of the material to be dried is small.

Effects of the Invention As is clear from the above embodiments, when the clothes dryer of the present invention detects a predetermined drying rate with the electrode, it detects the detected temperature difference between the first temperature sensing part and the second temperature sensing part. By determining the amount of material to be dried based on this temperature difference, it is possible to control the appropriate completion of drying for any amount of material to be dried.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing a conventional clothes dryer;
The figure is a sectional view of a clothes dryer showing an embodiment of the present invention, Figure 3 is a temperature characteristic diagram of the temperature sensing section when a small amount of drying material is put into the clothes dryer, and Figure 4 is the same. FIG. 5 is a flowchart of the clothes dryer, showing the temperature characteristics of the temperature sensing section when a large amount of material to be dried is put into the clothes dryer. 12... Rotating drum, 15... Heater, 16
... Fan, 17 ... Drum front plate, 18 ... Electrode, 19 ... Fan case, 20 ... First temperature sensing section, 21 ... Second temperature sensing section.

Claims (1)

[Claims] 1. A heater serving as a heat source, a rotating drum that rotates and stirs the material to be dried, a fan that introduces hot air from the heater into the rotating drum, and a fan case that surrounds the fan and is placed behind the rotating drum. a first provided in the fan case;
a temperature-sensing section; a drum front plate that pivotally supports the rotating drum in front and has a hot air outlet; an electrode that contacts the drying material in the rotating drum to detect the drying rate; A second temperature-sensing part is installed on the inner wall apart from the hot air outlet, and when a predetermined drying rate is detected by the electrode,
A clothes dryer that detects a temperature difference between the first temperature sensing section and the second temperature sensing section, determines the amount of material to be dried based on this temperature difference, and controls subsequent drying operation time.