JP3036068U - Low frequency electrical stimulator - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To reliably detect electrode detachment during low frequency treatment. SOLUTION: A treatment voltage output circuit 5 for outputting a voltage for treating a human body 9 at low frequency, and the electrode section 10 are provided.
And a voltage control circuit 4 for outputting a reference voltage VE for detecting contact between the human body 9 and a comparison voltage output means 7 for outputting a comparison voltage VF having a magnitude corresponding to the current supplied to the human body 9. And the reference voltage VE and the comparison voltage V
A comparison circuit 6 for comparing with F and a charging / discharging circuit 3 for generating a soft start control voltage VC according to the comparison result of the comparison circuit 6 are provided, and a small voltage that the human body 9 does not feel is applied. When the electrode unit 10 contacts the human body 9, the electrode unit 10 is gradually increased and the reference voltage VE is increased.
Is changed in proportion to the magnitude of the voltage output for the pulse treatment.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a low-frequency electrical stimulator, and more specifically, it is suitable for a low-frequency electrical stimulator that controls an output voltage that is output according to a contact state between an electrode unit and a human body. .

[0002]

[Prior art]

 As is well known, various low-frequency electrical stimulators have been put into practical use in the past, in which a low-frequency pulse is applied to a human body via a conductor to perform treatment by stimulation of the low-frequency pulse.

By the way, in recent low-frequency electrical stimulators, a human body and a conductor are electrically connected as proposed in, for example, Japanese Patent Application Laid-Open Nos. 3-77562 and 3-165784. When the human body and the conductor are electrically contacted with each other, the intensity of the low-frequency pulse is weakened and the magnitude of the low-frequency pulse is reduced with the passage of time. A so-called soft start function that gradually raises is being provided.

[0004]

[Problems to be solved by the device]

 Since there are various modes of treatment using the low-frequency electrical stimulator, for example, treatment may be performed on the human body while frequently repeating contact and detachment of the electrode part. Therefore, in order to realize the soft start function as described above in good condition, it is necessary to reliably detect the electrode unit each time it re-contacts the human body.

However, the human body detection means provided in the conventional low-frequency electrical stimulation apparatus flows between the pair of electrodes when the pair of electrodes comes into contact with the human body, and the impedance between the pair of electrodes is lowered, so that the current flows between them. Since the low frequency treatment is started by detecting the contact with the human body by detecting the increase in the magnitude of the electric current, the human body detection cannot be accurately performed after the low frequency treatment is started. there were.

That is, in the situation where the therapeutic effective current flows between the pair of electrode elements, the pulse output voltage is sufficiently higher than the human body detection start voltage. For this reason, when the electrode element is separated from the human body during treatment, a large pulsating current due to the capacity of the power supply line flows in the power supply line due to the large voltage.

To make matters worse, the output voltage during treatment increases when the load on the human body is removed, so that the current flowing in the power supply line increases, which detects that the electrode has detached. Making it difficult.

In view of the above problems, it is an object of the present invention to make it possible to reliably detect electrode detachment during low frequency treatment.

[0009]

[Means for Solving the Problems]

 The low-frequency electrical stimulator of the present invention detects whether or not the electrode part 10 and the human body 9 are electrically contacted, and soft-starts the low-frequency electrical stimulation to the human body 9 according to the detection output. In the low-frequency electrical stimulator, the therapeutic voltage output circuit 5 for outputting a voltage for low-frequency treatment of the human body 9, the electrode section 10 and the human body 9 are electrically contacted. A voltage control circuit 4 for outputting a reference voltage VE for detecting whether or not it is present, a comparison voltage output means 7 for outputting a comparison voltage VF having a magnitude corresponding to the current supplied to the human body 9, and the reference voltage VE. And the comparison voltage VF, and outputs a comparison result voltage VG corresponding to the comparison result, and a charging / discharging circuit that generates a soft start control voltage VC according to the comparison result of the comparison circuit 6. And a circuit 3, If a small current is applied by applying a small voltage that the human body 9 does not feel and the increase in the small current due to the contact of the electrode portion 10 with the human body 9 is detected, it is effective for low frequency pulse therapy. A feature is that the current is gradually increased to a certain magnitude and the magnitude of the reference voltage VE is changed in proportion to the magnitude of the voltage output for the low frequency pulse treatment. It is said.

Another feature of the present invention is that when the decrease in the human body load current is detected, the magnitude of the voltage output for the low frequency pulse treatment is set to the first detection start voltage. It is characterized in that it is immediately lowered to.

Another feature of the present invention is that a pseudo load 21 for flowing a current having a magnitude corresponding to the current supplied to the human body 9 is further provided, and the magnitude of the current flowing through the pseudo load 21 is further increased. Based on this, a reference voltage VE for detecting whether or not the electrode portion 10 and the human body 9 are electrically contacted is generated and output.

[0012]

[Action]

 Since the present invention has the above technical means, when the electrode unit 10 comes into contact with the human body 9, a small current flowing at a small voltage applied to the human body 9 at a level not felt by the human body 9 increases, and the current increases. Once detected, the current is gradually increased to a therapeutically effective magnitude and treatment with a low frequency pulse begins with a soft start.

Further, since the magnitude of the reference voltage VE is changed in proportion to the magnitude of the voltage output for the pulse treatment, the noise current having a large pulse characteristic caused by the capacity of the power supply line is generated. Detection of electrode detachment becomes easy.

[0014]

[Embodiment of the invention]

 Next, an embodiment of the low frequency electrical stimulation device of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows a first embodiment of the present invention and is a schematic configuration diagram of a low-frequency electrical stimulator. In FIG. 1, 1 is an output voltage setting circuit, 2 is a detection output setting circuit, 3 is a charging / discharging circuit, 4 is a voltage control circuit, 5 is an output circuit, 6 is a comparison circuit, 7 is a photocoupler, and 8 is a supply circuit. An electric wire and 9 represent loads (human bodies), respectively.

The output voltage setting circuit 1 is for setting the output voltage VA for performing treatment, and outputs the set output voltage VA to the charging / discharging circuit 3. The detection output setting circuit 2 is for setting the magnitude of the detection output voltage VB for detecting whether or not the electrode portion 10 (see FIG. 2) is in contact with the load 9, and is set. The detection output voltage VB is output to the voltage control circuit 4.

The charging / discharging circuit 3 generates the soft start control voltage VC by charging / discharging the output voltage VA input from the output voltage setting circuit 1, and the soft start control voltage VC generated as described above. Is output to the voltage control circuit 4.

The voltage control circuit 4 uses the detection output voltage VB supplied from the detection output setting circuit 2 and the soft start control voltage VC supplied from the charging / discharging circuit 3 to determine the therapeutic voltage VD and the reference voltage. Generate VE. The therapeutic voltage VD generated by the voltage control circuit 4 is applied to the output circuit 5, and the reference voltage VE is applied to the comparison circuit 6.

A pulse voltage is input to the output circuit 5 in addition to the therapeutic voltage VD given from the voltage control circuit 4, and the therapeutic voltage VD is supplied only during a period in which the pulse voltage is supplied. Is output to the photo coupler 7. Then, when the therapeutic voltage VD is output to the photocoupler 7, the booster transformer T1 boosts it to a high voltage of a predetermined magnitude suitable for the treatment.

The photocoupler 7 is provided to insulate the device body and the electrode part together with the transformer T1, and thereby greatly enhances the safety against an electric shock accident in the device using AC. I am able to

The photo coupler 7 outputs a comparison voltage VF having a magnitude proportional to the magnitude of the current output via the power supply line 8, and the comparison voltage VF is input to the comparison circuit 6.

The comparison circuit 6 generates a charging / discharging control voltage VG based on the input reference voltage VE and the comparison voltage VF, and controls the charging / discharging operation of the charging / discharging circuit 3 by the charging / discharging control voltage VG. .

The charging / discharging circuit 3 performs charging / discharging of the output voltage VA set by the output voltage setting circuit 1 in accordance with the charging / discharging control voltage VG given from the comparison circuit 6, and as described above, the software The start control voltage VC is output to the voltage control circuit 4.

Next, with reference to FIGS. 2 and 3, an example of a circuit embodying the present invention and its operation will be described in detail. FIG. 3 is a waveform diagram for explaining the operation of each part. Time point t1 is the timing when the electrode is in contact with the human body, time point t2 is the timing when the electrode is separated from the human body, and time point t3 is the setting of the output voltage VA. The time t4 indicates the timing when the electrode is in contact with the human body, and the time t5 indicates the timing when the electrode is separated from the human body.

First, the output voltage VA is set in the output voltage setting circuit 1, and the set output voltage VA is supplied to the charging / discharging circuit 3. Then, when the electrode portion 10 is brought into contact with the load 9 at the time point t1 shown in FIG. 3, a current starts to flow through the load 9. This current is a small current that is not felt by the human body, and by detecting the increase in this small current, the current is gradually increased to a magnitude that is effective for treatment, and treatment with a low-frequency pulse is performed. ing.

That is, when the current flowing in the photo coupler 7 increases due to the contact of the electrode portion 10 with the load 9 at time t1, the magnitude of the comparison voltage VF output from the photo coupler 7 to the comparison circuit 6 increases. To do.

The comparison circuit 6 is composed of a comparator (CMP1), and when the comparison voltage VF becomes larger than the reference voltage VE, the comparison circuit 6 inverts the polarity of the charge / discharge control voltage VG, The capacitor C0 of the charge / discharge circuit 3 is charged.

As a result, the terminal voltage of the capacitor C0, that is, the magnitude of the soft start control voltage VC given from the charging / discharging circuit 3 to the voltage control circuit 4 rises as shown in FIG. 3 (c). I will do it.

The voltage control circuit 4 is composed of an amplifier (AMP1), a transistor Q1, etc., and has a magnitude obtained by adding the soft start control voltage VC and the detection output voltage VB as shown in FIG. 3 (d). This voltage is output as the therapeutic voltage VD.

The therapeutic voltage VD output from the voltage control circuit 4 is supplied to the output circuit 5 as described above. The output circuit 5 is composed of a transistor Q2, a transformer T1 and the like. When a drive pulse is applied to the control electrode of the transistor Q2, a pulse current flows through the primary side of the transformer T1. A high voltage having a magnitude corresponding to the number of turns is induced on the secondary side of the transformer T1, and a therapeutic pulse current flows to the load 9 via the power supply line 8 and the electrode section 10. The power supply line 8 can be regarded equivalently as a distribution circuit of resistance and capacitance, as shown by resistors R8 to R13 and capacitors C5 to C6 in FIG. 2, and has a large distribution capacitance.

Therefore, in the state where the therapeutic effective current flows, the pulse therapeutic output voltage is sufficiently higher than the detection start voltage. Therefore, when the electrode unit 10 is separated from the human body during the treatment (time point t2), due to this large voltage, a large pulse current due to the capacity of the power supply line 8 flows in the power supply line 8.

Moreover, worse, the pulse therapy output voltage increases due to the removal of the human body (load). For this reason, it is difficult for the current flowing through the power supply line 8 to detect that the electrode portion 10 is separated from the human body. In order to solve such a problem, in the present embodiment, the magnitude of the reference voltage VE is increased according to the magnitude of the pulse therapy output voltage.

That is, in the low-frequency electrical stimulator of the present embodiment, while the low-frequency treatment is being performed, next, when the electrode unit 10 is separated from the load 9, the decrease in the human body load current is detected. Then, the pulse therapy output voltage is immediately lowered to the detection start voltage, and then the electrode unit 10 is prepared to detect whether or not the electrode unit 10 has contacted the human body.

By doing so, it is possible to prevent the electrode portion 10 from coming into contact with the next treatment point while the pulse treatment output voltage is high, so that the patient is given an electrical shock that occurs when the electrode portion 10 comes into contact. And the low frequency treatment can be well administered.

Further, even if the pulse therapy output voltage increases due to the removal of the human body (load), the reference voltage VE also increases accordingly, so whether or not the electrode portion 10 contacts the load 9 or It becomes possible to easily and surely detect whether or not the electrode portion 10 is separated from the load 9.

Therefore, the low-frequency electrical stimulation device of the present invention is particularly effective when used in a device that performs low-frequency treatment while moving the treatment point. For example, when the electrode part is formed in the shape of a glove, and the surface of the glove is used as an electrode, and this is used as an electrode, etc. , Can be effectively activated.

Next, a second embodiment of the present invention will be described with reference to FIGS. 4 and 5. The same parts in FIG. 4 as those in FIG. 1 and the same parts in FIG. 5 as those in FIG. 2 are designated by the same reference numerals and detailed description thereof will be omitted.

As shown in FIG. 4, in the second embodiment, a second photo coupler 20 and a pseudo load 21 are additionally provided. As shown in FIG. 5, the pseudo load 21 is composed of a parallel circuit of a resistor R5 and a capacitor C10, and is connected in parallel to the secondary side of the transformer T1. The second photocoupler 20 is provided to output a current having a magnitude proportional to the current flowing through the pseudo load 21 as the reference voltage VE.

In the second embodiment configured as described above, since a predetermined current is constantly applied to the pseudo load 21, the voltage on the power source side suddenly rises, so that the human body is affected. It is possible to prevent a shock from being given.

Further, the reference voltage VE for detecting whether or not the electrode unit 10 is in contact with the load 9 can be obtained with a magnitude proportional to the current flowing through the pseudo load 21, and thus the electrode It is possible to reliably detect contact and separation of the portion 10.

[0040]

[Effect of the invention]

 As described above, according to the present invention, when the electrode unit contacts the human body, a small current flowing at a small voltage applied to the human body increases so that the human body does not feel it. It is possible to reliably detect the contact with the. Then, when the increase in the current is detected, the magnitude of the current can be gradually increased to a magnitude effective for the treatment, and the low frequency pulse treatment can be surely soft-started.

Further, since the magnitude of the reference voltage is changed in proportion to the magnitude of the voltage output for pulse treatment, noise having a large pulse characteristic due to the capacity of the power supply line is generated. The electrode detachment due to the electric current can be easily detected.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the outline of a first embodiment of a low-frequency electrical stimulation device of the present invention.

FIG. 2 is a circuit diagram showing details of the low-frequency electrical stimulation device of the first embodiment.

FIG. 3 is a waveform diagram for explaining the operation of each unit.

FIG. 4 is a schematic diagram showing the outline of a second embodiment of the present invention.

FIG. 5 is a circuit diagram showing details of a low frequency electrical stimulation apparatus according to a second embodiment of the present invention.

[Explanation of symbols]

 1 Output Voltage Setting Circuit 2 Detection Output Setting Circuit 3 Charge / Discharge Circuit 4 Voltage Control Circuit 5 Output Circuit 6 Comparison Circuit 7 Photocoupler 8 Feed Line 9 Load (Human Body) 10 Electrode Section 20 Photocoupler 21 Pseudo Load

Claims (3)

[Utility model registration claims] 1. A low-frequency electrical stimulus for detecting whether or not the electrode part 10 and the human body 9 are electrically contacted, and soft-starting the low-frequency electrical stimulation for the human body 9 according to the detection output. In the device, a treatment voltage output circuit 5 for outputting a voltage for treating the human body 9 at a low frequency, and a device for detecting whether or not the electrode unit 10 and the human body 9 are electrically contacted The voltage control circuit 4 for outputting the reference voltage VE and the comparison voltage V of a magnitude corresponding to the current supplied to the human body 9
A comparison voltage output means 7 for outputting F, a comparison circuit 6 for comparing the reference voltage VE and the comparison voltage VF, and outputting a comparison result voltage VG corresponding to the comparison result, and a comparison result of the comparison circuit 6 And a charging / discharging circuit 3 for generating a soft start control voltage VC according to the above, and a small current is applied by applying a small voltage that the human body 9 does not feel so that the electrode unit 10 contacts the human body 9. Therefore, when the small increase in the current is detected, the current is gradually increased to a magnitude effective for the low frequency pulse treatment, and the magnitude of the reference voltage VE is output for the low frequency pulse treatment. A low-frequency electrical stimulator characterized in that it is changed in proportion to the magnitude of the applied voltage. 2. When the decrease in the human body load current is detected, the magnitude of the voltage output for the low frequency pulse treatment is immediately lowered to the first detection start voltage. The low frequency electrical stimulator according to claim 1. 3. A pseudo load 21 for supplying a current having a magnitude corresponding to the current supplied to the human body 9 is further provided, and the electrode section 10 is based on the magnitude of the current flowing through the pseudo load 21.
The low voltage according to claim 1, wherein a reference voltage VE for detecting whether or not the human body 9 and the human body 9 are electrically contacted is generated and output. Frequency electrical stimulator.