JPH08137561A - Power supply voltage controller - Google Patents

Abstract

PURPOSE: To provide a power supply voltage controller which can stabilize the voltage in a simple constitution and at a low cost. CONSTITUTION: A transformer 1 is provided with output taps 11 to 13 of different transformation ratios, and the switches SW 2a to 2c are loaded into the taps 11 to 13 and undergo the on/off control by the control signal of a control part 3. Then the part 3 monitors the voltage inputted to the transformer 1 and turns on only one of switches 2a to 2c to stabilize the output voltage in response to the coefficient of fluctuation of the input voltage. When the input voltage is equal to 90V, for example, only the switch 2c is turned on and the voltage is outputted from the tap 13 of 110% transformation ratio. Then the output voltage VO of the transformer 1 is shown as Vo=90V×110%=99V. Thus the voltage approximate to 100V is outputted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply voltage control device mounted on a game machine or the like for stabilizing the operation of an electric component such as a solenoid whose performance is affected by fluctuations in the power supply voltage.

[0002]

2. Description of the Related Art Generally, in an electric product such as a game machine, a commercial power source of 100 V or 200 V is stepped down by a transformer or the like, and this is used as a power source voltage to operate an electric part such as a solenoid. However, the performance of many electrical parts such as solenoids is affected by fluctuations in the power supply voltage, and if voltage fluctuations occur due to some cause, or if voltage fluctuations occur due to load fluctuations, etc.
The operation of the solenoid or the like may become unstable, and the operation of the main body device may become unstable.

To prevent this, a switching regulator is generally used as a power supply voltage control device, that is, as a voltage stabilizing means for keeping an output voltage substantially constant even when the power supply voltage or load changes. Since the switching regulator is lossless in principle, it has characteristics of high efficiency, small size, and light weight.

[0004]

However, since the switching regulator controls the input voltage on / off to keep the average voltage constant, it cannot be used without a smoothing circuit, and the response is poor. There are also many ripples. or,
There are many parts, and high voltage (10
The 0V) high current switching regulator is a specially ordered part and is expensive.

An object of the present invention is to provide a power supply voltage control device which solves the above-mentioned problems in the conventional power supply voltage control device and can stabilize the voltage at a low cost with a simple structure.

[0006]

According to the present invention, the above-mentioned problems can be solved by a transformer having a plurality of output taps having different transformation ratios, and can be turned on / off by a control signal which is connected to each tap of the transformer. Stable output voltage of the transformer by detecting a change in the power supply voltage input to the transformer and selectively turning on / off the switch connected to each tap according to the voltage change rate. It is solved by providing the control means which makes it change.

[0007]

[Function] A plurality of secondary side taps (output terminals) of the transformer, which are conventionally fixed, are provided with different transformation ratios, and a switch is attached to each tap. Then, the control unit monitors the voltage fluctuation on the primary side (input side), and selectively switches ON / OFF of each switch according to the fluctuation rate to output. This stabilizes the output voltage even if the input voltage fluctuates.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of one embodiment of the present invention. The power supply voltage control device shown in this figure is mounted on a game machine and stabilizes an input voltage in order to stabilize the operation of a solenoid or the like. As shown in this figure, the power supply voltage control device of this embodiment includes a transformer 1,
It is composed of switches (SW) 2a to 2c and a control unit 3. An alternating current (AC) of 100 V is input to the primary side (input side) of the transformer 1 from a commercial power source. This input is connected to the controller 3 and the input voltage is monitored. Further, the transformer 1 includes secondary side (output) taps 11 to 13 having different transformation ratios.
The tap 11 has a transformation ratio of 90% and the tap 12
Is 100% and the tap 13 is 110%. Then, the output lines of the taps 11 to 13 are combined into one after passing through the switches (SW) 2a to 2c, respectively, and form the output of the transformer 1 together with the output line 14.
Each of the switches 2a to 2c is a relay, and ON / OFF is controlled by a control signal from the control unit 3. The output of the transformer 1 is supplied to various parts in the game machine such as a solenoid.

FIG. 2 shows the circuit configuration of the input voltage monitoring unit in the control unit 3. Since the input voltage monitoring unit can have a conventionally known configuration, detailed description thereof will be omitted, but the power supply voltage is divided and input to the eight operational amplifiers 4a to 4h. Each operational amplifier sends an output corresponding to the input voltage to the IC 5, and further, via the photocouplers 6a and 6b, the CPU of the control unit 3 as 8-bit data of IN0 to IN7.
(See FIG. 3). The CPU of the control unit 3 determines what voltage the power supply voltage to be input to the transformer 1 is based on the data from the input voltage monitoring unit, and selects and outputs an output tap having a transformation ratio according to the voltage. In order to control ON / OFF of each switch (SW) 2a to 2c,
Stabilizes the output voltage from. In this embodiment,
When the input voltage to the transformer 1 is 93 V or less, the CPU turns off the switches 2a and 2b and turns on only the switch 2c. When the input voltage is within the range of 93V to 110V, the CPU turns off the switches 2a and 2c and turns on only the switch 2b. When the input voltage is 110 V or higher, the CPU turns off the switches 2b and 2c and turns on only the switch 2a.

For example, the input voltage to the transformer 1 is 90V
In this case, since the control unit 3 turns on only the switch 2c, the transformation ratio is 110% with respect to the input voltage of 90V, and the output voltage Vo of the transformer 1 is Vo = 90V × 1.
10% = 99V, which is a voltage close to 100V. Further, when the input voltage is 100V, only the switch 2b is turned on, so that the transformation ratio becomes 100%.
Output a voltage of 00V. Furthermore, the input voltage is 110V
If so, the CPU turns on only the switch 2a. As a result, the output voltage Vo of the transformer 1 is Vo = 1.
10V × 90% = 99V, which is a voltage close to 100V.

The solenoid used in the game machine to which the power supply voltage control device of this embodiment is mounted operates stably in the voltage range of 90V to 110V. That is, normal operation is not compensated for at other voltages. However, even when the input voltage to the transformer 1 is 120 V, the output voltage Vo of the transformer 1 is Vo = 1 by the power supply voltage control device of the present embodiment.
20V × 90% = 108V, which is output as a voltage within the stable operation range of the solenoid. Moreover, even if the input voltage to the transformer 1 becomes 85 V, for example, the transformer 1
Output voltage Vo is Vo = 85V × 110% = 93.5
It becomes V and is output as a voltage within the stable operation range of the solenoid.

By the way, in the on / off control of the switches (SW) 2a to 2c by the CPU of the control unit 3, it is important that only one switch is turned on and two or more switches are not turned on. Is. Otherwise,
An unnecessarily high voltage is output, and there is a risk of abnormal operation or damage to the connected electrical parts such as the solenoid.

FIG. 3 shows a circuit configuration of the switch control unit in the control unit 3. 4 connected to CPU 10
The retriggerable one-shot generators (hereinafter, abbreviated as one-shot generators) 7a to 7d output one-shot pulses at arbitrary times, and the outputs thereof are input to the decoder 8. The decoder 8 is a signal from the preceding stage including the pulse signal from the one-shot generator 7,
Only one of the three output terminals of 7 must be turned on. The signals output from the Y5 to 7 terminals of the decoder 8 are sent to the switches 2a to 2c shown in FIG. 1, respectively, and the relay of each switch is turned on / off.

In the power supply voltage control device of the present invention, the number of secondary side taps of the transformer and the transformation ratio thereof are not limited to those in this embodiment, and can be set arbitrarily. Furthermore, the same applies to the input voltage monitoring unit and the switch control unit of the control unit 3, and configurations other than this embodiment may be used. Since the transformer, the switch, the parts constituting the control unit, and the like that are generally commercially available can be used, the input power can be stabilized at a low price.

[0016]

As described above, according to the power supply voltage control device of the present invention, the fluctuation of the input voltage to the transformer is monitored by the control unit, and the secondary side tap is selected according to the voltage (rate of fluctuation). Since the ON / OFF of the connected switch is automatically controlled, the input voltage can be stabilized at a low cost with a simple configuration.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a configuration of an input voltage monitoring unit in a control unit of the power supply voltage control device.

FIG. 3 is a circuit diagram showing a configuration of a switch control unit in a control unit of the power supply voltage control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 transformer 2a-c switch 3 control part 4a-h operational amplifier 7 one-shot generator 8 decoder 10 CPU 11, 12, 13 output tap

Claims (1)

[Claims] 1. A transformer having a plurality of output taps having different transformation ratios, a switch connected to each tap of the transformer and capable of being turned on / off by a control signal, and a power supply voltage input to the transformer. Control means for detecting a change and selectively turning on / off a switch connected to each tap according to the voltage change rate to stabilize the output voltage of the transformer. Power supply voltage control device.