JPH0377562A - Low frequency treatment device - Google Patents

Abstract

PURPOSE:To detect the current flowing to a director even when there is the switching function of polarity by cyclically reversing the polarity of the low frequency pulse outputted to the director mounted on a human body and detecting that the human body and the director are electrically connected to gradually raise the low frequency pulse. CONSTITUTION:When the continuous pulse from the output terminal O1 of a control circuit 6 is inputted to a waveform shaping circuit 3, a condenser C4 is charged with the counter electromotive voltage of a coil L. The charge voltage of the condenser C4 is discharged by the pulses from output terminals O2, O4 and, when a current Ix flows to a human body, the input terminal I1 of a control circuit 6 changes from an H-level to an L-level. The control circuit 6 judges that the directors 5a, 5b and the human body are electrically connected on the basis of said change. Thereafter, the charge voltage of the condenser C4 is gradually boosted to apply a low frequency pulse to the human body through the directors 5a, 5b and the polarity of the voltage between the directors 5a, 5b is changed over. By this method, the currents flowing to the human body from the directors can be easily detected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a low-frequency treatment device that applies low-frequency pulses to a human body via a conductor.

[Prior Art] This type of low-frequency treatment device that applies low-frequency pulses to the human body via a conductor is described in Japanese Patent Publication No. 10109/1983.

[Problems to be Solved by the Invention] In this conventional example, whether or not the conductor is electrically connected to the human body is determined by a human body detection method using impedance. However, when changing the direction of the current flowing through the conductor (polarity switching), the voltage changes between positive and negative, making the decision circuit difficult.

The present invention has been provided in view of the above-mentioned points, and it is an object of the present invention to provide a low frequency treatment device that can easily detect a human body using the current flowing from the conductor to the human body even when switching the polarity. This is the purpose.

[Means for Solving the Problems] The present invention includes a polarity switching circuit that periodically reverses the polarity of a low-frequency pulse output to a conductor worn on the human body, and a current flowing through the conductor is detected by the polarity switching circuit. The device is equipped with a human body detection circuit that detects that the human body and the conductor are electrically connected, and a soft start circuit that gradually increases a low frequency pulse based on the output of the human body detection circuit.

[Function 1] The electric current flowing through the conductor is detected to detect that the human body and the conductor are electrically connected.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
The circuit diagram is shown in Figure 1. As shown in the figure, the low frequency treatment device is
A polarity switching circuit 1 that switches the direction of current flowing between a pair of conductors 5a and 5b, a human body detection circuit 2 that detects whether or not the conductors 5a and 5b are electrically connected to a human body, and a waveform shaping circuit 3, an internal discharge circuit 4, and a control circuit 6 for controlling each circuit. FIG. 2 shows a time chart, and points A-F in FIG. 2 correspond to points A-F in FIG. 1.

As shown in Figure 2, the series of operations of the low-frequency treatment device is to turn on the power switch SW+, start operation, detect a human body, output a low-frequency pulse with a soft start, and then The operation is completed and stopped after a predetermined time.

A continuous pulse as shown in FIG. 2(a) is output from the output terminal O1 of the control circuit 6, and when this pulse is input to the base of the transistor Tro+ of the waveform shaping circuit 3,
In the 0th order, the back electromotive force of the coil L is charged to the capacitor C1 via the diode D1 as shown in FIG. 2(b).
A pulse as shown in FIG. 2(e) is output from the output terminal O of the control circuit 6, and this pulse causes the transistor T
In order to turn on rB and turn on the transistor Try, and at the same time turn on the transistor Tr13, the capacitor C1
The charging voltage is discharged through the transistor T2°→conductor 5a→human body resistance Rx→conductor 5b→transistor T r + s→diode D2, and current Ix flows as shown in FIG. 2(f). Similarly, the output terminal 02 of the control circuit 6
A pulse as shown in FIG. 2(d) is output from Tr, and this pulse turns on transistors Tr33, Tr22, and Tr,2, and the transistor Tr2□→conductor 5b
→Human body resistance Rx→Conductor 5a→Transistor T r,
2→The capacitor C1 is discharged via the diode D2, and a current lx flows as shown in FIG. 2(f). By the above operation, the polarity of the voltage Vx applied to the human body resistance Rx is switched as shown in FIG. 2(e).

Next, human body detection will be explained. When the current lx flows through the human body as described above, the forward voltage of the diode D2 turns on the transistor Tr□, and the input terminal I of the control circuit 6, which has been at H level until now, becomes as shown in FIG. As shown in (g), it changes to L level. Here, the conductors 5a, 5
If b is not in contact with the human body, voltage Vx will not be generated,
On the control circuit 6 side, where no current IX flows, the input terminal I changes to the L level, thereby determining that the conductors 5a, 5b and the human body are electrically connected.

After that, perform a soft start, that is, gradually increase the charging voltage of the capacitor C1, and send a low frequency pulse to the conductor 5a.
5b to the human body. This is done by increasing the number of pulses output from the output terminal O8 of the control circuit 6 to increase the charging voltage of the capacitor C4, as shown in FIG. 2(a). Note that soft start may be performed by gradually increasing the pulse width of the low frequency pulse output to the human body, and in the normal low frequency pulse output state, the output terminal of the control circuit 6 Pulses are alternately output from 02 and 03 to switch the polarity of the voltage applied between the conductors 5a and 5b.

Also, by volume VR.

The intensity can be varied by changing the amplitude of the pulse. Note that the control circuit 6, waveform shaping circuit 3, etc. constitute a soft start circuit.

Here, before the soft start, as shown in FIG. 2(h), a pulse is output from the output terminal O1 of the control circuit 6, and this pulse is used to cause the transistor T of the internal discharge circuit 4 to
r3. is turned on to discharge the charge in the capacitor C4. This prevents shock to the human body due to excessive charging voltage of capacitor C4 immediately after soft start.

Furthermore, even at the end of the operation, as shown in FIG. 2(f), a pulse is output from the output terminal O1 of the control circuit 6 to discharge the charge in the capacitor C4.

[Effects of the Invention] As described above, the present invention includes a polarity switching circuit that periodically reverses the polarity of a low-frequency pulse output to a conductor worn on the human body, and a current flowing through the conductor is detected by the polarity switching circuit. It is equipped with a human body detection circuit that detects that the human body and the conductor are electrically connected, and a soft start circuit that gradually increases the low frequency pulse by the output of the human body detection circuit. Even if there is a switching function, it is possible to detect the electrical connection between the human body and the conductor by detecting the current flowing through the conductor, and it is possible to add a soft start function.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of an embodiment of the present invention, and FIG. 2 is a circuit diagram of an embodiment of the present invention. I is an operation waveform diagram same as above. 1 is a polarity switching circuit, 2 is a human body detection circuit, and 5a. 5b is a conductor.

Claims (1)

[Claims] (1) A polarity switching circuit that periodically reverses the polarity of the low-frequency pulse output to the conductor attached to the human body, and the polarity switching circuit detects the current flowing through the conductor and connects the human body and the conductor electrically. A low frequency treatment device comprising: a human body detection circuit that detects connection; and a soft start circuit that gradually increases a low frequency pulse by the output of the human body detection circuit.