JPS60200427A - Relay drive device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a relay driving device using a microcomputer for power control of equipment used in general households.

Conventional configuration and its problems Conventionally, when irons, rice cookers, etc. use a microcomputer to drive a relay and control the power of the heater, the program of the microcomputer (hereinafter referred to as microcomputer 3L) is run in synchronization with the power supply. In many cases,
In that case, the drive phase of the relay is fixed, which has the disadvantage of greatly shortening the sequentiality of the relay contacts. Since switching is performed in phase, from the point of view of the contacts, this means that direct current is being opened and closed at the highest voltage, making contact transitions more likely, and as a result, reducing the lifespan of the contacts. Recently, in order to solve this drawback, a method has been proposed in which one cycle is divided and the drive phase of the relay is sequentially changed, but the program is complicated. Then, a shift in the drive phase still occurs.

OBJECTS OF THE INVENTION The present invention eliminates the drawbacks of the conventional relay drive system and prevents the life of the relay contacts from decreasing.

Structure of the Invention The relay and drive device of the present invention include a power synchronization pulse generating means for generating a pulse synchronized with the power cycle, a counter means for manually counting and counting the power synchronization pulse, and a timing means for outputting the pulse asynchronously. and a reading means for reading the contents of the counter means based on the output of the timing means, and a time conversion means for converting the value read by the reading means into time. It is composed of a delay means for delaying the output from the displacement point of the power synchronization pulse, and a relay drive means for driving the relay by the output of the delay means, and randomly changing the phase of driving the relay during one cycle of the power supply cycle. It is something that changes.

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

FIG. 1 is a specific circuit diagram showing a relay driving device of the present invention when used in an iron, and FIG. 2 is a block diagram showing the configuration thereof.

The power source for the sea urchin circuit is created by half-wave rectifying the AC power source 1 and smoothing it with a capacitor 4. This DC power supply becomes the power supply for the microcomputer 6. Reference numeral 6 denotes a power synchronization pulse generation means for generating pulses synchronized with the power supply cycle, which includes a resistor 6a and a diode 6b.
Connect as shown in the figure and input its output to the S input of microcomputer 5. Reference numeral 7 denotes a timing means asynchronous to the power supply, and in the embodiment, a temperature detection circuit is shown. That is, a bridge circuit consisting of a resistor and a thermistor 9 is connected to the input terminal of the comparator 8, and the output terminal of the comparator 8 is connected to the I input of the microcomputer 5.

10 is a relay driving means, which is operated by the δ output of the microcomputer 6, which consists of a relay coil 11 that controls the contact 3 and a transistor 12 connected thereto.

The microcomputer 6 consists of four blocks: a counter means 13 for counting power synchronization pulses, a reading means 14 for reading a specific digit of the counter means 13, and a reading means 14 for converting the read value into a time. It consists of a time conversion means 16 that performs the conversion, and a delay means 16 that outputs a delayed signal by that time from the displacement point of the power synchronization pulse. The counter means 13 is a four-digit counter as shown in FIG.
A timer is created that counts the power frequency of 60Hz and lasts up to 160 seconds. That is, the lowest digit counts 5 power synchronization pulses and increases the digit □ to increase the 0.1 second digit.

The reading means 14 reads only the 0.1 second digit value of the counter means 13 at the output timing from the timing means 7. The read numerical value is converted by time conversion means 15. The conversion method at this time is 'r=(read value)X
2 <ms>. That is, the reading value is 0-9
Therefore, the output T of the time conversion means 16 varies from 0 to 1.
It changes at 8m54. This means that one cycle of the power supply cycle is 10
It corresponds to the divided value, and each phase is set to 0.
It corresponds to the numerical value of 1 second digit. The delay means 16 operates the relay driving means 10 with a delay of time T from the rising edge of the power synchronization pulse. In the above configuration, the opening/closing operation of the relay when controlling the temperature of the iron will be explained.

When the power is turned on and the microcomputer 5 starts operating, a power synchronizing pulse is input to the S input (see FIG. 4), so the counter means 13 counts the number of pulses as described above. On the other hand, the base surface temperature of the iron is detected by the thermistor 9, and if it is lower than the set temperature, the output of the comparator 8 becomes [LJ]. This signal is input to the microcontroller, but the timing is completely unrelated to the power supply cycle.
It depends on the temperature change state of the thermistor 9. At this timing, the reading means 14 operates and the counter means 13
Read the 00.1 second digit.

For example, if this numerical value is "2", the time conversion means 15 calculates 2X2=4 and instructs the next delay means 16 to have a delay time of 4 ms. In response to this instruction, the delay means 16 outputs a relay drive signal from the 6 ports 4 ms after the rise of the power synchronization pulse (time A in FIG. 4).

This is at point 2 in the power supply phase. Then, the contact 3 of the relay closes and current flows through the heater 2, increasing the temperature of the base surface of the iron. As the temperature of the base surface rises, the temperature of the thermistor 9 also rises, and when the set temperature is exceeded, the output of the comparator 8 reaches rHJ. This signal is input to the microcomputer 5, and again at this timing (asynchronous to the power supply cycle)
．． Read the digits of 1 second.

For example, if this reading value is 17'', the same process as described above is performed, and 14 m5 is obtained from the time of S human power A.
Afterwards, a signal to stop driving the relay is output from port 6. As a result, the contact 3 of the relay opens and the power supply to the heater 2 is stopped. The phase at this time is the 7 phase of the AC power supply. In this way, the relay contacts 3 open and close to control the base surface to the set temperature, and the phase in which the relay contacts 3 open and close changes randomly within one power cycle, and if it is biased toward a specific phase, the do not have.

Next, regarding the second embodiment, only the points different from the first embodiment will be described based on FIG.

The time conversion means 16 assigns the value read by the reading means 14 to a half cycle of the power supply cycle. That is, as shown in FIG. 5, for example, if the first value read is 12'', the time conversion means 15 performs a calculation of 2×1 ms and instructs the delay means 16 to set a delay time of 2 ms.

The delay means 16 receives all these instructions and outputs the relay drive signal from the 6 port 2 ms after the rise of the power synchronization pulse.

This is at point 2 in the power supply phase.

If the next read value is "7", the time conversion means 15 similarly converts 7 x 1 mfl into the delay means 16.
instruct. In response to this instruction, the delay means 16 outputs a relay drive signal from 6 baud 7 ms after the fall of the power supply synchronizing pulse. This is at point 7 in the power supply phase. In this way, the relay opens and closes repeatedly,
The opening and closing phases of the contacts are repeated alternately, with a negative phase followed by a positive phase. Moreover, the phase in a half cycle is random.

Effect of the invention The relay drive device of the present invention has the following effects: It's playing.

1. Since the opening/closing phase of the relay contacts changes randomly during one cycle of the AC power supply, it is not fixed at one point, and it is possible to prevent the contact life from being shortened due to transfer, etc.

2. The program is simpler than the one that sequentially changes the opening/closing phase of the contacts, and it is possible to prevent the opening/closing phase from shifting even if the number of openings and closings is very small.

[Brief explanation of drawings]

FIG. 1 is a specific circuit diagram showing an embodiment of the present invention, FIG. 2 is a block diagram showing the components, FIG. 3 is a configuration diagram of the counter means, and FIG. 4 is a diagram explaining the opening/closing phase of the relay. FIG. 6 is a diagram explaining the opening/closing phase of a relay showing another example different from FIG. 4. 6...Power synchronization pulse generation means, 7...
Timing means, 1o... Relay drive means, 1
3...Counter means, 14...Reading means, 15...Time conversion means, 16...
...delay means.

Claims (1)

[Claims] (1) power synchronization pulse generation means for generating pulses synchronized with the power cycle; counter means for inputting and counting the power synchronization pulses; timing means for outputting the pulses asynchronously; A reading means for reading the contents of the counter means, a time conversion means for converting the value read by the reading means into time, and a time conversion means for outputting a delayed value from the displacement point of the power synchronization pulse by the time set by the time conversion means. A relay driving device comprising a delay means and a relay drive means for driving the relay by the output of the delay means.The reading means reads only the value of a specific digit of the counter means. Driving device for the relay described in section ('4) The time conversion means divides one cycle of the power supply period into two.
7. The relay driving device according to claim 1, wherein each phase is made to correspond to a specific digit numerical value of the counter means. (→ The power supply synchronization pulse generation means generates a pulse that is a half-wave of the power supply, and the time conversion means divides the half cycle of the power supply period, makes each phase correspond to a specific digit value of the counter means, and 2. The relay driving device according to claim 1, wherein the delay means alternately delays the power synchronizing pulse from a positive displacement point and from a negative displacement point.