JPS6329558B2 - - Google Patents

Description

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

Structure of conventional example and its problems Conventionally, in this type of dryer, it has been common to use a mechanical timer or the like to set the operating time appropriately depending on the amount of cloth or the type of cloth. However, with this configuration, the timer setting relies on the user's experience and intuition, making it difficult to determine the optimal operating time. Therefore, problems such as over-drying or under-drying may occur due to incorrect setting of the operating time, which may damage clothes and waste electricity. There is also a method that detects the dry state by detecting the surface resistance of the cloth using an electrode and detecting the exhaust temperature using an exhaust temperature sensing element, but if the amount of cloth is small, the cloth may not come into contact with the electrode. Optimal drying conditions may not be detected. Furthermore, it is necessary to apply a high voltage to detect high resistance using electrodes, which poses a safety problem.

OBJECTS OF THE INVENTION The present invention solves the conventional problems as described above and provides a dryer control device that detects the optimum drying state regardless of the type of cloth or the amount of cloth.

Structure of the Invention The dryer control device of the present invention includes a first timer means that outputs a signal after counting a certain period of time;
Exhaust temperature detection means detects the exhaust gas temperature at the time when the timer means outputs a signal; first calculation means receives the output of the exhaust temperature detection means as input and calculates a rate of change in exhaust gas temperature; a first comparison means that compares the output with a predetermined value and outputs a control signal when the output of the first calculation means exceeds the predetermined value; and from the start of operation, the first comparison means outputs a control signal; a second timer means for measuring the time until the output of the second timer means; a second calculation means for determining a length of time according to the time measured by the second timer means; and a second comparing means which outputs a control signal when the output of the exhaust gas temperature detecting means exceeds a predetermined value, and a second comparing means which measures the time determined by the second calculating means and outputs a control signal While outputting
a third timer means for stopping time measurement and outputting a signal when the time measurement ends; a first control means for stopping operation of the heater when a control signal is output from the second comparison means; It is equipped with a second control means for stopping the operation of the heater and motor in response to the output signal of the timer means, and is configured to obtain an optimum drying state.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In FIG. 1, reference numeral 1 denotes exhaust temperature detection means of the dryer, which outputs a control signal to the first calculation means 3 when a control signal is input from the first timer means 2 which outputs a control signal after counting a certain period of time. The first calculating means 3 calculates the rate of change in exhaust gas temperature from the output of the exhaust temperature detecting means 1 and outputs it to the first comparing means 5. The first comparison means 5 compares the rate of change in exhaust gas temperature with a predetermined value, and outputs a control signal to the second calculation means 6 when the rate of change in exhaust gas temperature exceeds the predetermined value. Further, while the exhaust gas temperature change rate is less than the predetermined value, the loop shown in FIG. 5 is repeated. The second timer means 4 measures the time from the start of operation until the first comparison means 5 outputs the control signal. The second calculation means 6
When the control signal of the comparing means 5 is input, the second
A length of time is determined according to the time measured by the timer means 4. A second comparison means 7 compares the output of the exhaust gas temperature detection means 1 with a predetermined value, and outputs a control signal to the first control means 9 and the third timer means 8 when the exhaust gas temperature exceeds the predetermined value. . The first control means 9 cuts off the power to the heater 11 in response to the output signal of the second comparison means 7. The third timer means 8 measures the time determined by the second calculation means 6, and stops measuring time while the second comparison means 7 outputs a signal, that is, the heater 11 is not energized. When the time measurement ends, a control signal is output to the second control means 10. The second control means 10 cuts off the power to the heater 11 and motor 12 in response to the output signal of the third timer means 8, and completes the operation.

Next, the operation of the above structure will be explained based on FIGS. 2 to 5. When the dryer starts operating, the heater 11 and motor 12 are energized and the exhaust temperature rises, but the change varies depending on the amount of cloth as shown in FIG. 2. In FIG. 2, D ₁ indicates a case where the amount of fabric is small, D ₂ indicates a case where the amount of fabric is medium, and D ₃ indicates a case where the amount of fabric is large.

Then, when the first timer means 2 starts measuring time and outputs a control signal after counting for a certain period of time, the exhaust temperature detecting means 1 detects the exhaust temperature and outputs it to the first calculating means 3. The first calculating means 3 calculates the exhaust gas temperature change rate from the exhaust gas temperature and outputs it to the first comparing means 5. This rate of change in exhaust gas temperature is shown in FIG. D ₁ indicates a case where the amount of fabric is small, D ₂ indicates a case where the amount of fabric is medium, and D ₃ indicates a case where the amount of fabric is large. The first comparing means 5 outputs a control signal to the second calculating means 6 when the output of the first calculating means 3 is greater than or equal to ΔT. The second timer means 4 starts measuring time from the start of operation, and measures the time until the first comparison means 5 outputs the control signal. As shown in FIG. 2, this time is t ₃ when the amount of cloth is large, t ₂ when the amount of cloth is medium, and t ₁ when the amount of cloth is small. Also,
In FIG. 2, T ₁ , T ₂ , and T ₃ indicate the operating time of the dryer required for the drying rate to reach a predetermined value (for example, 100%) when the amount of cloth is small, medium, or large.
That is, it shows the time for energizing the heater from times t ₁ , t ₂ , and t ₃ , that is, the delay time. These times have a relationship as shown in FIG. 4, and are expressed by the following arithmetic expression.

T=At+B...(1) T: Delay time from time t until the drying rate reaches a predetermined value t: Operating time of the dryer when the exhaust temperature rise value reaches the set value ΔT A, B constants The second calculation means 6 calculates the output of the second timer means 4 according to the calculation formula (1), and determines the delay times T ₁ , T ₂ , and T ₃ . The second comparison means 7 compares the output of the exhaust gas temperature detection means 1 with a predetermined value (for example, 65° C.), and only when the exhaust gas temperature exceeds the predetermined value, the first control means 9 and the third timer means 8 Outputs a control signal to. Said first control means 9
The power supply to the heater 11 is cut off while the output signal of the second comparing means 7 is being outputted. The third timer means 8 measures the time determined by the second calculation means 6, and stops counting while the second comparison means 7 outputs the output signal.
That is, only the net time during which the heater 11 is energized is counted, and a control signal is output to the second control means 10 when the time measurement is finished. The second control means 10 turns off the power to the heater 11 and motor 12 in response to the output signal of the third timer means 8, thereby completing the operation. In this way, the third timer means measures the heater energization time required for the cloth to reach a predetermined drying rate, that is, the predetermined delay time, and when this time measurement is completed, the cloth has reached the predetermined drying rate. has reached. The flow of the above operations is as shown in the flowchart of FIG.

In this way, since the operation is controlled using the exhaust temperature as an input signal, the drying completion state of the cloth can be accurately detected without being affected by the type or amount of cloth.

In addition, although the control device is configured by a microcomputer in the embodiment, it is clear that the control device is not necessarily limited to this.

Effects of the Invention As is clear from the above description, according to the present invention, the length of the subsequent operation time is determined according to the time when the rate of change in exhaust gas temperature reaches a predetermined value, and the OFF time of the heater is , it is not added to the driving time, so
When the operation is stopped, the dryness of the cloth reliably reaches a predetermined value, and the cloth will not become undried or overdried.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a control device showing the configuration of the present invention, Fig. 2 is a characteristic diagram showing the operating time of the dryer and exhaust temperature, and Fig. 3 shows the operating time of the dryer and the rate of change in exhaust gas temperature. Figure 4 is a diagram showing the relationship between the time when the exhaust gas temperature change rate reaches the set value ΔT and the heater ON time from the time when the exhaust gas temperature change rate reaches the set value ΔT until the drying rate reaches the predetermined value. FIG. 5 is a flowchart of the operation of the control device. DESCRIPTION OF SYMBOLS 1... Exhaust temperature detection means, 2... First timer means, 3... First calculating means, 4... Second timer means, 5... First comparing means, 6... Second calculating means, 7... ... second comparison means, 8 ... third timer means, 9 ... first control means, 10 ... second control means, 11 ... heater, 12 ... motor.

Claims (1)

[Claims] 1. A first timer means that outputs a signal after counting a certain period of time; an exhaust temperature detection means that detects the exhaust gas temperature at the time when the first timer means outputs the signal; A first calculation means for calculating the rate of temperature change compares the output of this first calculation means with a predetermined value, and
a first comparison means that outputs a control signal when the output of the calculation means exceeds the predetermined value; and a second timer that measures the time from the start of operation until the first comparison means outputs the control signal. a second calculation means for determining a length of time according to the clocked time of the second timer means, and a second calculation means that compares the output of the exhaust temperature detection means with a predetermined value, and compares the output of the exhaust temperature detection means with a predetermined value. A second comparison means outputs a control signal when the value exceeds a predetermined value, and a time determined by the second calculation means is measured, and the time measurement is stopped while the second comparison means outputs the control signal. , a third timer means for outputting a signal when the time measurement ends; a first control means for stopping the operation of the heater when the second comparison means outputs a control signal; and an output of the third timer means. A control device for a dryer comprising a second control means for stopping operation of a heater and a motor in response to a signal.