JPS629348B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a voltage regulating circuit that can be used in particular to constant output voltage in a battery-powered low-frequency therapy device.

Configuration of conventional example and its problems The output section of the conventional battery-powered low frequency treatment device is
It was like the picture. However, in the configuration shown in FIG. 1, the power supply voltage of the dry cell and timer circuit section 1 is switched by a transistor based on the output of the oscillation circuit section 2, and is used as the primary power source of the output transformer 4. If the voltage fluctuates, the output voltage will change even though the scale position of the output adjustment volume 3 is the same value, and the output voltage will change.
The reliability of the scale was poor. In FIG. 1, a conductor (not shown) to be attached to a living body is connected to terminals a and b on the secondary side of the output transformer 4 by a pin jack or the like.

Purpose of the Invention The present invention aims to eliminate the above-mentioned drawbacks of the conventional technology, by making the output voltage of a battery-powered low-frequency treatment device constant regardless of fluctuations in the battery power supply voltage, and improving the reliability of the scale of the output voltage versus output adjustment volume. The present invention provides an improved battery-powered low-frequency treatment device.

Structure of the Invention The present invention connects a series circuit of an output transistor and a field effect transistor in series to an output adjustment volume constituting an output voltage adjustment circuit, and changes the conduction resistance of the field effect transistor in accordance with fluctuations in battery voltage. , which maintains the output voltage constant through transformer coupling.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to FIGS. 2 and 3.

FIG. 2 shows a block diagram of the circuit configuration of the dry battery type low frequency treatment device of the present invention. In FIG. 2, a power switch 7 whose one end is connected to a dry cell battery 6 is connected to a timer circuit section 8, which counts the modulation period of the pulse modulation oscillation circuit section 9 and starts the timer circuit section 8 when a set count is reached. Run it and configure the power supply timer. When the timer circuit section 8 is on, power is supplied to the entire circuit section, which will be described later. The oscillation circuit section 10 oscillates a pulse with a "tatak" feeling, the oscillation circuit sections 10, 11 and the AND gate circuit section 12 oscillate a pulse with a "mom" feel, and the pulse modulation oscillation circuit section 9 oscillates a pulse with a "mom" feel. Creates oscillation with varying number of pulses. One of the oscillations is selected by the mode changeover switch 13. The selected oscillation is connected to the monostable multi-oscillation circuit section 14, which converts it into oscillation with a constant pulse width, and output voltage stabilization and adjustment circuit section 15, output amplification circuit section 16, and polarity changeover switch 17. The circuit of the battery-powered low-frequency treatment device according to the present invention is configured by connecting to the circuit.

FIG. 3 shows a specific circuit diagram of the dry battery type low frequency treatment device according to the present invention. In FIG. 3, when the power switch 7 is turned on, the counter IC ₁ of the timer circuit section 8 is turned on by the capacitor C ₁ and the resistor R ₁ .
is reset and the output goes to a lower level, so
The transistor TR ₁ is turned on through the resistor R ₃ connected to the output. The transistor _TR1 is
When turned ON, power is supplied to the pulse modulation oscillation circuit section 9, so that the oscillation circuit composed of resistors R ₁₇ , R ₁₈ , R ₁₉ , capacitor C ₁₂ , and programmable unidirectional transistor PUT ₁ operates.
The oscillation output is connected to counter IC ₂ , and when the pulse count reaches the set value, the output is input to IC ₁ of timer circuit section 8, IC ₁ is activated, transistor TR ₁ is turned off, and the power is turned off. Configures a timer circuit section. When the transistor TR ₁ is ON, the pulse modulation oscillation circuit section 9, the oscillation circuit section 10,
11 is activated, and the changeover switch 13 selects one output of the three oscillation states. The selected oscillation output is input to the monostable multi-oscillation circuit section 14, where it is converted into oscillation with a constant pulse width, and the output voltage stabilization and output voltage adjustment circuit section 15, which is the main circuit section of the present invention, output amplification. The signal is output through the circuit section 16 and the polarity switch 17.

The output voltage stabilization and output voltage adjustment circuit section 15, which is the main circuit section of the present invention, will be specifically explained below.

The output end of the monostable multi-oscillation circuit section 14 is a resistor.
It is connected to the base of the output transistor _TR5 by _R35 , the emitter of the output transistor _TR5 is connected to the source of the field effect transistor _FET1 , and the collector is connected to the output adjustment volume _VR2 . The drain of the field effect transistor FET ₁ is connected to the power supply voltage Vcc. A constant current circuit is constructed with a field effect transistor FET ₂ , a volume VR ₃ , and a resistor R _{15 .}
Make the terminal voltage constant. The gate of the field effect transistor FET ₁ is connected to one end of a resistor R ₁₅ to apply a constant bias voltage. It is connected to the base of the transistor TR ₄ of the output amplifier circuit 16 by means of a resistor R ₁₄ connected to the output adjustment volume VR ₂ . Transistors TR ₃ and TR ₄ are connected in Darlington, and the output transformer is connected to the emitter of transistor TR _3.
Connect the primary side of T ₁ and amplify it.

When the dry cell power supply voltage is the final voltage, the specified voltage is obtained on the secondary side of the output transformer _T1 .
Adjust the volume VR ₃ above. Incidentally, conductors (not shown) are connected to the output terminals a and b of the polarity changeover switch 17, and by switching the polarity changeover switch 17, the stimulation can be freely changed to the right or left.

When the circuit is configured as above, the dry battery power supply voltage is high, and the power supply voltage Vcc is the field effect transistor.
When the voltage is higher than the gate bias voltage of FET ₁ , the conduction resistance between the drain and source of the field effect transistor FET ₁ increases, and when the power supply voltage Vcc changes to be lower than the gate bias voltage of the field effect transistor FET _1. , the conduction resistance decreases and always the transistor TR ₅ , the output adjustment volume
The current flowing through VR ₂ and resistor R ₁₆ becomes constant. Since the base of the transistor TR ₄ of the output amplifier circuit 16 is connected to the output adjustment volume VR ₂ via the resistor R ₁₄ , the bias voltage at the base of the transistor TR ₄ remains constant regardless of fluctuations in the power supply voltage Vcc. Since a constant bias voltage is applied, a constant current flows through the primary side of the output transformer _T1 , and the secondary output of the output transformer _T1 is stabilized. Furthermore, it is clear that by varying the output adjustment volume _VR2 , the voltage on the secondary side of the output transformer _T1 can be varied.

Effects of the Invention As is clear from the above description, the present invention provides an output voltage adjustment circuit that stabilizes the output voltage of the oscillation circuit when a signal from the oscillation circuit is input and responds to fluctuations in the dry battery power supply voltage. The structure is constructed by connecting in series a field effect transistor whose conduction resistance between the drain and source increases or decreases, and an output adjustment volume serving as the output terminal via an output transistor, so the output voltage remains constant regardless of fluctuations in the battery power supply voltage. As a result, the relationship between the output voltage and the scale of the output adjustment volume remains constant regardless of fluctuations in the dry battery power supply voltage, which improves the reliability of the scale. be.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional battery-powered low-frequency therapy device, FIG. 2 is a block diagram of a battery-powered low-frequency therapy device according to an embodiment of the present invention, and FIG. 3 is a circuit showing the specific circuit configuration. It is a diagram. 6... Dry battery, 10, 11... Oscillation circuit section, 14...
Monostable multi-oscillation circuit section, 15... Output voltage adjustment circuit section, 16... Output amplifier circuit section, TR ₅ ... Output transistor, FET ₁ ... Field effect transistor, VR ₂ ...
Output adjustment volume, T ₁ ...output transformer.

Claims (1)

[Claims] 1. A dry cell that constitutes a power source, an oscillation circuit that generates low-frequency pulses, an output voltage adjustment circuit that stabilizes the output voltage of this oscillation circuit, and a battery that is connected to the output end of this output voltage adjustment circuit. and an output amplifier circuit section including an output transformer, and the output voltage adjustment circuit section receives the signal from the oscillation circuit section, and increases or decreases the conduction resistance between the drain and the source according to fluctuations in the dry battery power supply voltage. This is a battery-powered low-frequency treatment device that consists of a field-effect transistor connected in series with an output adjustment volume that serves as the output end via an output transistor.