JPS6218817B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a clothes dryer using a positive resistance temperature characteristic element (hereinafter simply referred to as a P element) in an intake air heater, and particularly relates to a clothes dryer which is intended to shorten the drying time of the clothes dryer. It's about machines.

Conventionally, clothes dryers that use P elements in the intake air (outside air) heaters have been commercially available, as they are considered to be fire-safe. Since the amount is designed to be constant, due to the nature of the P element, its calorific value decreases as the temperature of the intake air increases.

In addition, since clothes dryers are used at outside temperatures ranging from 0°C in the winter to 35°C in the summer, the heat output of the P element in the winter must be selected to be the maximum value of the general household power supply. As a result, when the outside air temperature is 15°C to 35°C in spring, autumn, and summer, the amount of heat generated is less than the maximum value of the household power supply, which has the disadvantage that drying time increases as the outside temperature increases.

In particular, since clothes dryers are most frequently used during the rainy season, the extended drying time when the outside temperature is between 15°C and 30°C poses a problem when using clothes dryers.

This will be explained in more detail with reference to FIG.

FIG. 1 is a characteristic diagram 1 showing the relationship between the intake air temperature and the calorific value when the amount of air is constant for the P element. In this Figure 1, point a indicates the maximum of 1.5Kw of the general household power supply (in the case of 15A breaker), and point b is the maximum value of the P element calorific value, which varies from the above 1.5Kw to the rotating drum and fan. The power consumption of the drive motor of 0.15 to 0.25Kw is deducted.
It is 1.25Kw.

Point c is P at the temperature of the intake air to the P element, 0°C.
The calorific value of the element, point d, indicates the calorific value at an air temperature of 25°C.

Normally, clothes dryers are used indoors, so it is sufficient to consider that the minimum outside temperature is 0℃, and as mentioned above, if the power consumption of the clothes dryer is 1.5Kw when the outside temperature is 0℃, P The element heat generation must be set to 1.25Kw. Therefore, when the outside temperature is, for example, 25° C., the P element calorific value is reduced by 200 W (difference between point c and point d) than when it is 0° C., resulting in a longer drying time.

The present invention eliminates the above-mentioned drawbacks of the prior art,
Clothes drying that maintains the P element calorific value constant or almost constant even if the temperature of the intake air changes, and shortens the drying time when the outside air condition is from room temperature to high temperature (15 to 35 degrees Celsius), i.e. from spring, autumn to summer. Its purpose is to provide equipment.

The clothes dryer of the present invention is characterized in that the clothes dryer uses a positive resistance temperature characteristic element in a heater that heats intake air, and includes a detection device that detects the temperature of the intake air to the positive resistance temperature characteristic element; When the detected value of the detection device increases (temperature rise), increasing the amount of air passing through the positive resistance temperature characteristic element,
When the detected value decreases (temperature decreases), by reducing the amount of air passing through the positive resistance temperature characteristic element, the amount of heat generated by the positive resistance temperature characteristic element can be adjusted regardless of the temperature of the intake air. This is a clothes dryer equipped with a device that controls the amount of air that can be kept almost constant.

To explain in detail, the amount of heat generated by the P element decreases as the intake air temperature increases, as shown in Figure 1, and as the amount of air passing through the P element increases, as shown in Figure 2. It increases with

Therefore, if the amount of air passing through the P element is controlled to increase when the intake air temperature rises, the amount of heat generated by the P element can be maintained constant regardless of the intake air temperature.

In addition, the P-element heat generation amount is calculated by subtracting the power consumption of the rotating drum and fan drive motor (0.15 to 0.25Kw) from the general household power source (1.5Kw), which is the maximum power that can be used for P-element heat generation (1.25Kw). Kw), the P element calorific value can be increased and the drying time can be shortened when the outside air condition is from room temperature to high temperature (15 to 35°C).

Hereinafter, the present invention will be explained with reference to Examples.

FIG. 3 is a side sectional view of an exhaust type clothes dryer according to an embodiment of the present invention, FIG. 4 is an enlarged perspective view showing details of the heating section using PTC in FIG. 3, and FIG. , VV sectional view of FIG. 4 (including the inflow duct 2), and FIG. 6 is an enlarged sectional view showing details of the air amount control device 15 of FIG. 3.

In Fig. 3, 1 is an outer frame, 2 is an inflow duct fixed to the outer frame 1, 3 is a door for putting in clothes, and 4 is an inflow duct fixed to the outer frame 1.
5 is a rotating drum;
A filter for removing cloth waste provided in the rotating drum 5, 7 a fan for ventilation, 8 a fan casing, 9 a motor for driving the rotating drum 5 and the fan 7, 10 a fan pulley, 11,1
2 is a motor pulley, 13 is a fan belt, 14 is a drum belt, and 15 is used to increase the amount of air passing through the P element 4 when the temperature of the intake air increases, and when the temperature of the intake air decreases. , by reducing the amount of air passing through the P element 4, P
An air amount control device (details will be described later) that can keep the calorific value of the element 4 almost constant regardless of the temperature of the intake air, 16 is an air port of the outer frame 1, 17 is
This is an exhaust port provided at the tip of the fan casing 8.

4 and 5, the heater P
The element will be explained.

4 is a disk-shaped P element, 4a is a small hole-shaped ventilation passage bored through the P element 4, 18;
19 is provided in contact with the periphery of both surfaces of the P element 4,
These electrode plates 18 and 19 are electrode plates for supplying electricity to the P element 4, and the P element 4 is fixed to the P element holder 20 (an electrical insulator).

The electrode plate 18 has an arcuate portion 18b at its center, and an electrode plate air port 18a is provided in the arcuate portion 18b.
is open. Further, an electrode plate air port 1 is also provided at a position of the electrode plate 19 facing the electrode plate air port 18a.
9a is open (see Figure 6).

As shown in the figure (Fig. 4), the P element 4 has a circular arc portion 1.
Two pieces are arranged on each side of 8b.

Next, the air control device will be explained with reference to FIG.

21 is a bimetal that is provided on the air intake side of the P element 4 and deforms depending on the temperature of the intake air (however, the upper piece has a larger coefficient of expansion); 22 is a bimetal that deforms depending on the temperature of the intake air;
An arc-shaped air amount adjusting piece is attached to the tip of the bimetal 21 and slides on the surface of the arc portion 18b as the bimetal 21 deforms; 23 is a metal frame of the bimetal 21; 24 is a metal frame 23 connected to the inflow duct 2 It is a holder that is fixed to the

In each figure, B is the intake air (outside air) into the inflow duct 2, C is the air passing through the gap between the tip 22a of the air volume adjustment piece 22 and the electrode plate air port 18a, and A is the air flowing into the P element 4. The air passing through the ventilation path 4a is shown, and each amount of air has the following relationship. That is, the amount of air in B=the amount of air in C+the amount of air in A. Next, the operation of this embodiment will be explained.

In FIG. 3, when clothes are put into the rotating drum 5 through the door 3 and the motor 9 is driven, the fan 7
rotates at high speed, and rotating drum 5 rotates at low speed. Air B enters the inflow duct 2 from the air port 16 of the outer frame 1 by the fan 7, is heated by the P element 4 (details will be described later), and then sent to the rotating drum 5. Inside the rotating drum 5, the heated air removes moisture from the clothes, leaves the rotating drum 5, passes through the fan casing 8, and is discharged outside the machine through the exhaust port 17.

Next, to explain the operation of the air amount control device 15 that controls the amount of heat generated by the P element 4, when the temperature of the intake air B (outside air) rises, the bimetal 21 becomes convex upward (the state shown in Fig. 6). Deformed, bimetal 2
The air amount adjusting piece 22 provided at the tip of the electrode plate 18
It moves downward while sliding the arcuate portion 18b of the adjustment piece 22, thereby reducing the area of the air passage between the tip 22a of the adjustment piece 22 and the electrode plate air port 18a, and increasing the ventilation resistance of this air passage. Therefore, the amount of air A passing through the ventilation path 4a of the P element 4 is increased, and the amount of heat generated by the P element 4 is increased.

In this example, by making the amount of increase in the P element calorific value match the calorific value that decreases as the intake air temperature increases as shown in FIG.
The amount of heat generated by the element is kept constant regardless of the temperature of the intake air.

A method of controlling the P element heat generation amount will be explained with reference to FIG. ~ are the ventilation passages 4 of the P element 4, respectively.
The relationship between the intake air temperature and the P element calorific value is shown for each amount of air passing through a (the amount of air increases as it becomes empty). In this figure 7, P
The amount of air passing through the element is set to a small amount when the air temperature is 0°C in winter, a slightly larger amount when the air temperature is 20°C in spring and autumn, and a slightly larger amount of air when the air temperature is 20°C in the summer.
In the case of 30°C, the amount of air is further increased, and if adjusted respectively, the P element heat generation amount c ₁ ,
c ₃ and c ₄ can be set constant regardless of the intake air temperature. Further, the set value of the P element heat generation amount is set to the electric power obtained by subtracting the power consumption of the motor from the general household power supply of 1.5 Kw.

According to an experiment using the exhaust type clothes dryer of this example, when 2 kg of clothes were dried at an outside temperature of 20°C, the P element heat generation amount increased (as shown in Figure 7).
The difference between c ₃ and d ₃ ) can be as high as 100 to 200W, and the drying time
Save 10-15 minutes.

Although this embodiment describes an exhaust-type clothes dryer, the method for controlling the P element calorific value according to the present invention can also be applied to a condensation-type clothes dryer (the exhaust after drying from the rotating drum is transferred to a heat exchanger). The dehumidified air is then cooled and dehumidified using a heat exchanger, and the dehumidified air is heated again and circulated within the rotating drum as drying air.
In this condensation type clothes dryer, since the air is circulated, the temperature of the intake air of the P element reaches 40° C. or more as shown in FIG. 8, so the effect of increasing the amount of heat generated by the P element is large.

According to experiments, when the outside temperature is 40° C., the increase in the P element heat generation amount (difference between c ₅ and d ₅ in FIG. 7) is more than 300 W, and the drying time can be shortened by more than 20 minutes.

In addition, in the above embodiment, it was stated that the P element calorific value is constant regardless of the temperature of the intake air, but it does not need to be strictly constant, and if the dispersion of the calorific value is within ±30 W, for example, The increase in calorific value is 100~200w (for condensed type)
300w), the drying performance can be sufficiently improved.

As described above in the examples, the calorific value of the P element can be maintained constant regardless of the temperature of the intake air (outside air), from spring and autumn when the outside air temperature is around 15°C to summer when it is high at around 30°C. , and can shorten drying time, especially during the rainy season (outside temperature 25-30°C) when clothes dryers are frequently used.

Furthermore, since the P element heat generation amount can be controlled with a simple structure consisting of only a bimetal and an air amount adjusting piece provided at the tip of the bimetal, the drying performance of the clothes dryer can be improved without increasing costs.

As explained in detail above, according to the present invention, the problem of insufficient heat generation of the P element in the summer can be solved, and even if the temperature of intake air changes, the P element calorific value can be kept constant or almost constant. It is possible to obtain a clothes dryer that can reduce the drying time when the outside air condition is from room temperature to high temperature, that is, from spring and autumn to summer.

[Brief explanation of the drawing]

Figure 1 is a characteristic diagram showing the relationship between the intake air temperature and calorific value of the P element when the air volume is constant. Characteristic diagrams 2 and 3 showing the relationship with heat generation amount are side sectional views of an exhaust type clothes dryer according to an embodiment of the present invention, and FIG. 4 is a heating section using the P element in FIG. 3. FIG. 5 is an enlarged perspective view showing details of the air flow control device shown in FIG. 7 are explanatory diagrams illustrating a method of controlling the P element heat generation amount,
FIG. 8 is a temperature change diagram showing the temperature change of air taken into the P element in a condensation type clothes dryer. 4... Positive resistance temperature characteristic element, 4a... Ventilation path, 15
...Air amount control device, 21...Bimetal, 22...Air amount control valve.

Claims (1)

[Claims] 1. In a clothes dryer using a positive resistance temperature characteristic element in a heater for heating intake air, a detection device for detecting the temperature of the intake air to the positive resistance temperature characteristic element, and the detection device When the detected value of increases (temperature rise), the amount of air passing through the positive resistance temperature characteristic element is increased, and when the detected value decreases (temperature decreases), the amount of air passing through the positive resistance temperature characteristic element increases. and an air amount control device capable of making the amount of heat generated by the positive resistance temperature characteristic element substantially constant regardless of the temperature of the intake air by reducing the amount of air passing through the positive resistance temperature characteristic element. Clothes dryer. 2 A bimetal is used as the detection device, and an air amount adjustment piece is attached to the tip of the bimetal as the air amount control device to adjust the area of the air path that is juxtaposed with the air path of the positive resistance temperature characteristic element. A clothes dryer according to claim 1.