JPH0148795B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) This invention relates to a method for determining dryness in a clothes dryer.

(Prior art) Conventionally, clothes dryers have been controlled temporally using a time switch, but this temporal control is extremely difficult because it varies depending on the amount and type of items to be dried, the hot air temperature, etc. Have difficulty.

Conventional dryness detection devices for automatic clothes dryers include methods that detect the humidity of clothes and convert it into an electrical signal, and devices that utilize the rapid rise in exhaust temperature as drying approaches completion. Also, the items to be dried are limited to items that have been washed with water.

(Problem to be Solved by the Invention) However, for clothes that have been washed using dry cleaning methods using organic solvents, a reliable clothes drying control device is required, but there is none in the past, and the drying method relies on the operator's eyes and senses. The reality is that there are.

As shown in the graph in Figure 1, the exhaust temperature of a general dryer changes over time during the initial residual heat period T ₁
It is divided into a medium constant rate period T ₂ and a final decreasing rate period T ₃ .

First, the applicant focused on the decreasing rate period _T3 at the end of the rising curve in the winter of 1985, read the temperature change during this period, inputted it into the calculation function of the microcomputer, determined the numerical value, and determined the drying time. Although the dryer was configured to control the drying time, the hot air temperature was set in the dryer to protect the items to be dried.
The curve It was just something for exclusive use.

Therefore, the applicant focused on the initial preheating period _T1 , and as a result of experiments, the temperature increase during the preheating period, regardless of the type or condition of the material to be dried,
It was found that changes were reliably shown in response to the amount and type of clothing or the state of dehydration. (See Figures 2 and 3) From this, the experiment revealed that if the temperature increase that changes during the initial preheating period is replaced with a value called the temperature increase rate, an appropriate drying time can be automatically set. .

[Structure of the invention]

(Means for Solving the Problems) Therefore, this invention can be applied to dry cleaning methods by capturing changes in exhaust gas temperature during this preheating period _T1 , and improves low-performance automatic control devices with a narrow range of application. To provide a method for determining the degree of dryness in an automatic clothes dryer that has wide applicability to various types of items to be dried, is adaptable to changes in the amount of items to be dried, performs reliable drying, and is inexpensive. It is something.

Hereinafter, one embodiment of the present invention will be described in detail. In a clothes dryer, the exhaust temperature within the dryer is
It consists of a device that reads the change in _T1 , inputs it into the arithmetic function of a microcomputer set in the dryer, obtains a numerical value, determines the drying time according to this numerical value, and controls the drying time accordingly.
In addition, the temperature increase that changes during the initial preheating period T ₁ is several minutes from the initial preheating period T ₁ ,
Now suppose that the initial temperature (when the clothes dryer starts) is
If the temperature is 20℃ and the exhaust temperature is measured with a temperature sensor 4 minutes after the initial temperature (Δt) and it is 40℃, the temperature increase will be 20 (40 minus 20).

The microcomputer has variable tables for laundry (washing with water) and drying (solvent), which can be changed by switching channels. The numerical value is 67. This value was determined as a result of repeated experiments.

In addition, the numerical value of strong (in the case of 100% drying) in the variable table of the dry cleaning method is set to 10 lower than that of washing with water, that is, 57.

Now, if you want to strongly (100%) dry clothes that have been washed, if the initial temperature is 20℃, and Δt of the residual heat period _T1 at the exhaust temperature is 40℃, then subtract the initial temperature of 20℃ and get 20. , subtracting the previous value 20 from the display 67 in the variable table of the microcomputer yields 47.
The calculated value is 43 after subtracting 4 minutes from the previous period, and this 43 is the drying time.

However, the starting temperature of a clothes dryer varies depending on the season and is not constant.

Therefore, in this experiment, the starting temperature was always kept at 20°C and the values in the variable table were determined.
Therefore, if the starting temperature exceeds or falls below 20°C, corrections are made within the microcomputer using calculation functions depending on the degree.
Further, the calculation method shown above is only an example of implementation, and any other calculation method can be used to implement the calculation method.

The temperature change in the exhaust temperature inside the dryer 1 during the preheating period T ₁ can be read using the temperature sensor 2 installed on the clothes dryer side. This is done by detecting heat.

〔Effect of the invention〕

According to this invention, since the drying time is determined by a microcomputer using the temperature change of the exhaust air temperature in the dryer during the preheating period, it can be applied to the drying process performed by the dry cleaning method. Since it is possible to detect accurate changes depending on the amount, type, and condition of the liquid, it has a wide range of applications, and has extremely beneficial effects such as reliable complete drying to semi-drying.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between exhaust temperature and time in a dryer, and FIG. 2 is a graph showing a curve of exhaust temperature and temperature change up to 100% drying in the present invention. A is dry thin material;
A' is a graph showing the temperature change curves until 100% drying for dry thick material, A'' is for thin rounded material, and A is for thick rounded material. Then, change the amount [c: 98% dry matter added, c′: 75% dry matter added, c″:
Figure 4 is a flowchart showing an example of the method of using the present invention.
FIG. 5 is a sectional view showing the mounting location of the temperature sensor used in this invention. 1...Dryer, 2...Temperature sensor, 3...Rotating cylinder, 4...Small hole, 5...Heat source, 6, 6'...Motor, 7...Blower, T ₁ ...Residual heat of exhaust temperature Period, Δt...at the time of measurement.

Claims (1)

[Claims] 1. In a clothes dryer that controls dryness using a computer, read the temperature or humidity change in the exhaust temperature inside the dryer during the residual heat period _T1 , input it into the calculation function of the microcomputer installed in the dryer, and calculate the numerical value. A method for determining the degree of dryness in a clothes dryer, characterized in that the drying time is determined in accordance with this numerical value, and the drying time is thereby controlled.