JPS6147119B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for controlling a drum-type dryer for drying clothes and the like used in general households with hot air.

Conventional configuration and problems Conventionally, this type of dryer uses a mechanical timer, in which the user sets the operating time that he or she deems appropriate based on past experience and intuition, depending on the amount or type of cloth. was common. However, with this configuration, it is difficult to determine the optimal operating time, and incorrect setting of the operating time may result in over-drying or under-drying.
There were problems such as damaging clothing and wasting electricity.

There is also a method of directly detecting the surface resistance of the cloth to detect the dry state, but since only the surface of thick cloth dries first, even if dryness is detected, the entire cloth will not be dry. Furthermore, since this method detects the surface resistance of the cloth, it was necessary to detect high resistance, and there were many problems with the circuit.

OBJECTS OF THE INVENTION The present invention solves these conventional problems and provides a dryer control method that performs optimal dryness detection regardless of the type of cloth or the amount of cloth.

Composition of the Invention The dryer control method of the present invention provides a dryer operating time from the time when the rate of change in the exhaust gas temperature of the dryer detected by the exhaust temperature detection device becomes equal to or higher than a specified value until the dryer reaches the specified value. This system delays the operation of the dryer by a more proportionally calculated delay time, allowing optimal drying to be performed using a single sensor.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. In FIG. 1, reference numeral 1 denotes an exhaust temperature detection device that detects the exhaust temperature of the dryer. 2 is an operating time counting device that counts the operating time of the dryer from the start of operation. 3 is an arithmetic and control device that receives the output of the exhaust gas temperature detection device 1, calculates temporal changes, and calculates the rate of change in the exhaust gas temperature. Further, the arithmetic control device 3 receives the output of the operation time counting device 2,
The operating time is calculated by putting it into the first function, and the rate of change in the exhaust gas temperature is compared with the calculated value of the operating time. If the rate of change in the exhaust gas temperature is larger, the operating time is set to the second specified value. A delay time is calculated by entering the function, and the heater 4 and motor 5 of the dryer are continuously operated, and when the delay time has elapsed, the heater 4 and motor 5 are stopped.

FIG. 2 shows the basic pattern of how the exhaust temperature changes as drying progresses. Period A is a preheating drying period, B is a constant rate drying period, and C is a decreasing rate drying period. The changes shown in FIG. 2 change as shown in FIG. 4 depending on the amount of cloth. Third
The figure shows the temporal change rate ΔT/Δt of the exhaust temperature when the amount of cloth is large (T ₃ ), medium (T ₂ ), and small (T ₁ ). Straight line 6 in the figure indicates the end of constant rate drying period B;
Points P ₁ to _{P 3} that move to the decreasing rate drying period C are connected. The formula is ΔT/Δt-A _t +B (1) ΔT/Δt: Temporal change in exhaust temperature t: Operating time AB: Expressed as a constant. However, since the above equation (1) is also satisfied during the preheating drying period A, it is necessary to stop the operation of the exhaust gas temperature detection device 1 during this period. The purpose of the above equation (1) is to find the point at which constant rate drying period B ends and transition to decreasing rate drying period C, and to detect a specified drying rate based on that point. I will discuss this next. Figure 4 shows the temporal change in exhaust temperature when the amount of cloth is large, medium, and small, and t ₁ , t ₂ , and t ₃ are the constant rate drying periods when the amount of cloth is small, medium, and large. It is the operating time of the dryer at the time when B ends and the transition to the decreasing rate drying period C,
t _e1 , t _e2 , and t _e3 are operating times of the dryer at the time when a specified drying rate (for example, 100%) is reached when the amount of cloth is small, medium, or large. It has been found that there is a relationship between these as shown in Figure 5. This formula is: T ₀ = C _t + D (2) T ₀ : Operating time of the dryer at the point when the drying rate reaches the specified value t : Drying time when the constant rate drying period ends and shifts to the decreasing rate drying period Machine operating time C, D: Expressed as constants.

Therefore, the specified drying rate is obtained by delaying the operation of the dryer by T ₀ determined by equation (2) based on the operating time t of the dryer when detected by equation (1). It is something.

As mentioned above, the preheating and constant rate drying period has ended,
The operating time of the dryer before entering the lapse rate drying period,
There is a strong correlation between the operating time of the dryer until the specified drying rate is reached during the decreasing rate drying period, and this can be used to detect dryness reliably.

Effects of the Invention The dryer control method of the present invention provides a delay time calculated proportionally to the operating time of the dryer from the time when the rate of change of the exhaust gas temperature of the dryer exceeds a specified value until it reaches the specified value. This device detects the optimal drying condition by delaying the operation of the dryer by only one sensor, and is excellent in that it only requires one sensor and can reliably detect dryness at low cost regardless of the type of fabric or amount of fabric. It is something that is having an effect.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a control method showing an embodiment of the present invention, Fig. 2 is a characteristic diagram showing the operating time of the dryer and changes in exhaust temperature, and Fig. 3 is a diagram showing the operating time of the dryer and the amount of cloth. Figure 4 is a characteristic diagram showing the rate of change in exhaust temperature over time. Figure 4 is a characteristic diagram showing changes in exhaust temperature depending on the operating time of the dryer and the amount of cloth. Figure 5 is a characteristic diagram showing the change in exhaust temperature depending on the operating time of the dryer and the amount of cloth. Figure 5 is a characteristic diagram showing the change in exhaust temperature over time. It is a relationship characteristic diagram between the operating time of the dryer at the time of transfer and the operating time of the dryer when the dryer reaches a specified value. 1...Exhaust temperature detection device, 2...Operation time counting device, 3...Arithmetic control device.

Claims (1)

[Claims] 1. From the moment the rate of change in the exhaust temperature of the dryer detected by the exhaust temperature detection device exceeds the specified value,
A dryer control method for delaying the operation of the dryer by a delay time proportionally calculated from the operating time of the dryer until the specified value is reached.