JPS61249479A - Living body stimulating apparatus using variable magnetic field - 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 This invention relates to a biological stimulator used for artificially deriving signals from a living body used in medical examinations, and a biological stimulation device used for resuscitation during cardiac arrest. The present invention relates to a stimulator and a biological stimulator used for investigating nerve transection sites, etc.

Problems to be Solved by the Invention With conventional electrical biostimulators, for example, when a subject is relatively obese in an electromyogram test, the stimulation voltage is significantly lowered because the nerves are relatively deep. There is a problem in that it must be applied continuously at a large volume, causing significant pain.

The purpose of the present invention is to solve these problems and non-invasively provide stimulation with little pain even deep within the body.

Construction of the invention As shown in FIG. 1, the present invention is comprised of a stimulation coil section, a control section, and a power supply section. The stimulation coil section is formed of a coil whose magnetic core is made of ferromagnetic material. The control unit includes a diode D that absorbs an induced back electromotive force generated by the stimulation coil and generates a single polarity induced electromotive force;
It is formed of a gate turn-off thyristor GTO that electrically connects and disconnects the stimulation coil section and the power supply section, and a positive and negative trigger signal generation circuit 1 that controls the gate turn-off thyristor GTO. The resistance R shown in the diagram N1 represents the sum of various resistances included in the current path of the capacitor C. The power supply section is formed by a capacitor C having a relatively large capacity, a charging circuit 2 that charges the capacitor C, and a switch SW that electrically disconnects the charging circuit 2 from the capacitor C after charging is completed.

Here, between the inductance value of the stimulating coil L in Fig. 1, the resistance value R of the resistor R included in the discharge current path of the capacitor C, and the capacitance value C of the capacitor C, there is a In order to efficiently supply the energy to the stimulation coil section, the following conditions are required.

In addition, the pulse width of the induced electromotive force generated by the stimulation coil is Toeφ, so in order to widen the variable range of the pulse width,
It is necessary to make the values of L and C relatively large.

As shown in Fig. 2, the induced electromotive force generated by the stimulating coil L is generated by passing positive and negative gate currents with an arbitrary time difference through the gate G of the gate turn-off thyristor GTO. state and off state, the pulse voltage has a pulse width approximately equal to the time difference between the positive and negative gate currents.

In addition to this, a practical control circuit is shown in FIG.

This control operation will be explained using FIGS. 3 and 4. First, a trigger signal generated from the positive trigger signal generation circuit 1 causes a gate current to flow through the gate G of the thyristor 5CR1 to turn on the thyristor SCR1, and then a photo Input/output isolation circuit 2 and delay circuit 3 such as couplers and pulse transformers
After that, a gate current is applied to the gate G of thyristor SCR2 and the thyristor SCR2 is turned on using a trigger signal with an arbitrary time delay after the previous trigger signal.
The thyristor SCR1 is turned off and generates an induced electromotive force of a pulse wave having a pulse width approximately equal to the time difference between the two trigger signals.

Further, the amplitude of the induced electromotive force generated by the stimulating coil L can be changed by changing the charging voltage of the capacitor 〇.

Effects of the Invention The present invention has the effect of making it possible to derive biological signals with much less painful stimulation than conventional electrical biological stimulation devices.

[Brief explanation of drawings]

FIG. 1 is a circuit configuration diagram of the present invention, FIG. 2 is an operation explanatory diagram explaining the invention in detail, FIG. 3 is a control circuit diagram, and FIG. 4 is an operation explanatory diagram explaining the operation. Fig. 1-11 Positive and negative trigger signal generation circuit 2-m-Charging circuit D---Diode CTO--One gate turn-off thyristor Fig. 2 G--One gate K---One cando A---Anode Figure 3 1-1 positive trigger signal generation circuit 2-1 output isolation circuit 3-m-delay circuit 5CRI, 2--thyristor

Claims (1)

[Claims] A biological stimulation device in which the pulse width and amplitude of induced electromotive force accompanying a fluctuating magnetic field are variable.