JPH03124295A - Microcomputer - Google Patents

Abstract

PURPOSE:To simplify a program configuration by operating the set value of phase control by a program only when suction air flow rate is altered. CONSTITUTION:When suction air flow is for, example, set to an 'intermediate' rate by operating means 14, a system controller 10 sets corresponding data in a timer buffer 4 by a control program stored in a ROM 12. When zero cross detecting means 1 detects the zero-crossing point of a commercial power source 9, the buffer 4 outputs a stored value to a binary counter 3, the counter 3 turns OFF an output unit 5 and then starts counting the output pulse from an oscillator 2. When the count of the counter 3 reaches the end and the unit 5 is turned ON, a bidirectional controller 17 is turned ON, and a voltage is applied on a motor 19. This operation is repeated each time the means 1 detects the zero- crossing point, and the phase of a motor 19 is controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a microcomputer used for industrial purposes.

Conventional Technology Conventionally, when using a microcomputer to control the phase of a motor or heater, it was achieved using a program. Figure 3 shows the flow of operation. When the zero crossing point is detected,
Set the initial value to the microcomputer's built-in timer and start the timer count. The timer count progresses separately from other normal processing programs, and when the timer count ends, an interrupt occurs. When an interrupt occurs, the flow of the program is transferred to the interrupt processing section, where the timer count ends, output control is performed, and the flow returns to the normal processing program.

Problems to be Solved by the Invention However, in the above configuration, the phase control is controlled by a program, and there is a problem that the program configuration becomes complicated. The present invention is intended to solve these conventional problems, and it is an object of the present invention to provide a microcomputer whose program structure can be simplified.

Means for Solving the Problems In order to achieve the second object, the present invention includes a zero-cross detection means for detecting a zero-cross point of a commercial power supply and outputting a signal, an oscillator, and a signal output from the zero-cross detection means. a binary counter that starts counting the output of the oscillator from time to time; a timer buffer that stores the initial count value of the binary counter and outputs the stored value when a signal is output from the zero-cross detection means; It consists of an output section that outputs a signal when the binary counter finishes counting.

Operation In the above-mentioned means, in order to perform phase control, the binary counter starts counting from the zero-crossing point of the commercial power supply,
It can be configured to output after the count ends.

Embodiments Hereinafter, embodiments will be described with reference to the drawings. FIG. 1 is a block diagram showing one embodiment of the present invention. In this embodiment, an example in which the present invention is applied to a control circuit for a vacuum cleaner will be described. 1
is a zero-cross detection means that detects the zero-cross point of the commercial power supply 9 via a resistor 15 and a resistor 16. 2 is an oscillator,
Pulse oscillation is performed at a frequency determined by the resistor 7 and capacitor 8. 3 is a binary counter, and zero cross detection means 1
When there is an output from the oscillator 2, counting of the pulse output of the oscillator 2 is started. 4 is a timer buffer, which loads a stored value into the binary counter 3 when there is an output from the zero-cross detection means 1; A system control unit 10 controls the entire microcomputer 21. 12 is ROM
Stores the vacuum cleaner control program. 11 is RAM
It is used to temporarily store data when executing a control program. Reference numeral 14 denotes an operating means for setting the suction air volume of the vacuum cleaner, and inputting the set value via the input section I3. A bidirectional control element 17 controls the motor 19. 5 is an output section, which is output when the binary counter 3 finishes counting. The output section 5 is composed of an NPN transistor, and at the time of output, it is connected to the bidirectional control element 1 via a resistor 18.
Turn on 7. 20 is a DC power supply for the circuit.

The operation will be explained below. The operating means 14 sets the suction air volume of the vacuum cleaner to "strong".

It can be set to three levels: medium and weak. For these three stages of suction air volume, as shown in Figure 2, ``at high power, the voltage applied to the motor is in all phases (Fig.
In the same case, the voltage is applied after tl from the zero-crossing point (Figure (C)), and in the same case, the voltage is applied after t2 from the zero-crossing point in the weak-power case.
A voltage is applied later (1'J(d)). Further, the binary counter 3 is composed of, for example, 8 bits, and is capable of counting 256 bits. Similarly, the timer buffer 4 is also composed of 8 bits. When the suction air volume is set to 'medium' by the operation means 14, the system control unit 10 uses the control program stored in the ROM 12 to send data corresponding to the suction air volume 'medium' to the timer via the internal data bus 6. Set in buffer 4. If the commercial power supply 9 is 60 Hz, this value will be 176. This corresponds to tl in (C) of Fig. 2, and is (8,33m5sc/256) x (256 -1
This corresponds to 76>-2,6m5ec. That is, the voltage is applied to the motor 19 after 2.6 m5 eC from the zero cross point (phase control is applied after 2.6 m5 eC has elapsed). When the zero-cross detection means 1 detects the zero-cross point of the commercial power supply 9 and outputs a pulse (Fig. 2 (a)),
Timer buffer 4 outputs the stored value to binary counter 3. At the same time, the binary counter 3 turns off the output section 5 and then starts counting the output pulses of the oscillator 2. The oscillation frequency of the oscillator 2, together with the resistor 7 and capacitor 8, is 1/(60Hz x 2 x 256) - 30, 7kHz.
Let it be z. Since the binary counter 3 is set to 176 as an initial value, when 80 pulses are input from the oscillator 2, the count value of the binary counter 3 becomes 256, which is the end of counting, and the output section 5 is turned on. Then, the bidirectional control element 17 is turned on via the resistor 18, and voltage is applied to the motor 19. This series of operations is repeated every time the zero-cross detection means 1 detects a zero-cross point, and phase control of the motor 19 is realized.

In this embodiment, an example in which the present invention is used to control the suction motor of a vacuum cleaner is explained, but it goes without saying that the same effect can be obtained when the present invention is used to control the phase of other motors, heaters, etc.

Effects of the Invention As is clear from the above explanation, in the present invention, the phase control set value is manipulated by the program only when the suction air volume of the vacuum cleaner is changed, and otherwise the phase control is possible regardless of the program. This makes it possible to provide a microcomputer that makes program design easier.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing the relationship between phase control and suction air volume, and FIG.
2 is a flowchart that realizes phase control using a conventional program. 1... Zero cross detection means, 2... Oscillator, 3...
・Binary counter, 4...Timer buffer.

Claims (1)

[Claims] a zero-crossing detection means for detecting a zero-crossing point of a commercial power supply and outputting a signal; an oscillator; a binary counter that starts counting the output of the oscillator from the time when a signal is output from the zero-crossing detection means; A microcomputer comprising: a timer buffer that stores a value at the initial stage of counting and outputs the stored value when a signal is output from the zero-cross detection means; and an output section that outputs a signal when the binary counter finishes counting.