CN109908472B - Electric therapy device - Google Patents

Abstract

An object of the present application is to provide an electrotherapy apparatus capable of generating various electric stimuli by a plurality of electrodes which can perform any one of functions of a reference electrode and an output electrode while controlling the electrotherapy apparatus easily. The present application provides an electrotherapy apparatus, characterized in that each of a plurality of switching circuits of the electrotherapy apparatus is provided with: a first transistor including a first upstream terminal connected to the electrode, a first downstream terminal connected to a reference potential, and a first switch terminal; a second transistor having a second upstream terminal connected to the output terminal, a second downstream terminal connected to the electrode and the first upstream terminal, and a second switch terminal, and having opposite characteristics; one end of the first resistor is connected with the output terminal, and the other end of the first resistor is connected with the second switch terminal; and a second resistor having one end connected to the second switch terminal and the other end connected to the first upstream side terminal of the other switch circuit.

Description

Electric therapeutic equipment

Technical Field

The present application relates to an electric therapeutic apparatus, and more particularly, to an electric therapeutic apparatus for giving electric stimulation to muscles inside the body.

Background

In general, there is known an electrotherapy device in which a plurality of electrodes are attached to the surface of a body such as the abdomen or back, and low-frequency pulses are output to muscles in the body via the electrodes to apply electrical stimulation. Such electrotherapeutics are used for such treatments to alleviate muscle stiffness. Further, the electrotherapy apparatus can repeat contraction of muscles by electric stimulation, and thus can be used for enhancement of muscle strength or training for weight reduction.

As a conventional electrotherapy apparatus, for example, as disclosed in patent document 1, there is an electrostimulation apparatus which has two electrodes in contact with a body, and which causes a voltage to flow between the electrodes to apply an electric current to apply electric stimulation to muscles. However, since such an electro-stimulation device has only two electrodes, the stimulation by the current is monotonous, and there is a problem in that the therapeutic effect and the training effect are insufficient.

Based on such a problem, an electrotherapy apparatus having a plurality of electrodes has been newly developed. For example, in patent document 2, a plurality of pads (electrodes) are used, and pulse voltages are sequentially applied, thereby improving the training effect of the body. In patent document 3, a plurality of electrodes are provided, and a switch for switching on or off is controlled for each electrode, so that the electrode for generating a current is periodically changed to apply various stimuli to the body, thereby improving the therapeutic effect.

Patent document 1: japanese patent laid-open No. 2005-245585

Patent document 2: japanese patent application laid-open No. 2010-131253

Patent document 3: japanese patent laid-open No. 2015-16041

However, in patent document 2, the pad set to the reference potential is fixed to the one-pole pad, and the pulse voltage cannot be applied to the one-pole pad. Therefore, current always flows toward the one-pole pad, but current cannot flow from the one-pole pad, and thus there is a problem that current stimulation is monotonous.

In patent document 3, a first switch for controlling electrical connection to the output potential of the pulse and a second switch for controlling electrical connection to the reference potential are used for each electrode. In other words, it is designed that each electrode can be either one of the potential of the output pulse and the reference potential (ground) by controlling the switch provided in two for each electrode. However, if two switches are provided for each electrode, control signals need to be supplied to the respective two switches, and thus control becomes complicated, the capacity of the memory increases, and the like, which causes a problem that the cost of electronic components increases.

Disclosure of Invention

Accordingly, an object of the present application is to provide an electrotherapy apparatus capable of setting each electrode to either an electrode for generating an output or an electrode for setting the electrode to a reference potential by simple control.

In the application disclosed in the present application, the outline of the representative embodiment will be briefly described as follows. That is, an electrotherapy apparatus for applying electrical stimulation to muscles in a body according to the present application includes: a plurality of electrodes in contact with the body; a control unit; an output intensity adjusting unit for outputting a predetermined voltage to the output terminal; and

a plurality of switching circuits corresponding to the plurality of electrodes, respectively, each of the plurality of switching circuits including: a first transistor including a first upstream terminal electrically connected to a corresponding electrode, a first downstream terminal electrically connected to a reference potential, and a first switch terminal electrically connected to the control unit and determining an on state and an off state according to a voltage set by the control unit; a second transistor including a second upstream side terminal connected to the output terminal, a second downstream side terminal connected to the electrode and the first upstream side terminal, and a second switch terminal for determining an on state and an off state according to a voltage, the second transistor having a characteristic opposite to that of the first transistor; a first resistor having one end connected to the output terminal and the other end connected to the second switch terminal; and a second resistor having one end connected to the second switch terminal and the other end connected to the first upstream side terminal of the corresponding other switch circuit, wherein the control unit is configured to turn on one first transistor of the plurality of switch circuits, turn off the remaining first transistors of the plurality of switch circuits, and determine a resistance value of the first resistor and a resistance value of the second resistor so that the second transistor is turned on when the one first transistor of the other switch circuit is turned on.

In the above-described electrotherapy apparatus, it is preferable that the first transistor is an FET. In this case, it is preferable that the three electrodes are fixed to the outer surface of the electrotherapy device so as to be positioned at the apexes of a substantially regular triangle. The number of the plurality of electrodes is preferably four, but may be two or five or more. Further, it is preferable that the control unit sequentially switches the first transistors in the on state at predetermined time intervals.

According to the present application, the control unit can set the electrode at the reference potential and the electrode at the output potential by controlling only the first transistor. That is, in the electrotherapy apparatus, since the control is simple, and each electrode can perform any of the functions of the reference electrode and the output electrode, and various electric stimuli can be generated, a particularly good effect that electric stimuli having a higher therapeutic effect can be given can be obtained.

Drawings

Fig. 1 is a block diagram schematically showing the structure of an electrotherapy apparatus 10 according to an embodiment of the present application.

Fig. 2A is a circuit diagram showing a circuit included in the output switching unit 14 of the electrotherapy device 10 according to the embodiment of the present application.

Fig. 2B is a diagram illustrating a circuit operation in which the second transistor 22B is turned on and an output potential is output to the second electrode 12B in the circuit diagram shown in fig. 2A.

Fig. 2C is a diagram illustrating a circuit operation in which the second transistor 22b is turned on and the second transistor 22A is turned off in the circuit diagram shown in fig. 2A.

Fig. 3 is a schematic diagram showing electrical stimulation of the electrotherapy apparatus 10 according to the embodiment of the present application.

Fig. 4 is a schematic diagram showing the effect of electrical stimulation in the alternate output mode of the electrotherapy apparatus 10 according to the embodiment of the present application.

Fig. 5A is a schematic diagram showing the effect of electrical stimulation in the rotational output mode of the electrotherapy apparatus 10 according to the embodiment of the present application.

Fig. 5B is a schematic diagram showing the effect of electrical stimulation applied in a direction different from that of fig. 5A in the rotational output mode of the electric therapeutic apparatus 10 according to the embodiment of the present application.

Fig. 5C is a schematic diagram showing the effect of electrical stimulation applied in a direction different from that of fig. 5A and 5B in the rotational output mode of the electric therapeutic apparatus 10 according to the embodiment of the present application.

Fig. 6 is a circuit diagram showing a circuit included in the output switching unit 34 of the electrotherapy device 30 according to another embodiment of the present application.

Reference numerals illustrate: 10 … electrotherapeutic apparatus; 11 … shell; 12 … electrode; 13 … control part; 14 … output switching section; 15 … output adjuster; a 16 … power supply control unit; 17 … cell; 18 … input device; 18a … power switch; 18b … mode select switch; 18c, 18d … output strong and weak switches; 19 … power display LED;20 … switching circuit; 21 … first transistor; 22 … second transistor; 23 … first resistor; 24 … second resistor; 32 … electrode; 33 … control part; 34 … output switching section; 35 … output adjuster; 40 … switching circuit; 41 … first transistor; 42 … second transistor; 43 … first resistor; 44 … second resistor.

Detailed Description

An electrotherapy apparatus according to an embodiment of the present application is described below with reference to the drawings. Fig. 1 is a block diagram schematically showing the structure of an electrotherapy apparatus 10 according to an embodiment of the present application. Fig. 2A is a circuit diagram showing a circuit included in the output switching unit 14 of the electrotherapy device 10 according to the embodiment of the present application. Fig. 2B is a diagram illustrating a circuit operation in which the second transistor 22B is turned on and an output potential is output to the second electrode 12B in the circuit diagram shown in fig. 2A. Fig. 2C is a diagram illustrating a circuit operation in which the second transistor 22b is turned on and the second transistor 22A is turned off in the circuit diagram shown in fig. 2A. Fig. 3 is a schematic diagram showing electrical stimulation of the electrotherapy apparatus 10 according to the embodiment of the present application. Fig. 4 is a schematic diagram showing the effect of electrical stimulation in the alternate output mode of the electrotherapy apparatus 10 according to the embodiment of the present application. Fig. 5A is a schematic diagram showing the effect of electrical stimulation in the rotational output mode of the electrotherapy apparatus 10 according to the embodiment of the present application. Fig. 5B is a schematic diagram showing the effect of electrical stimulation applied in a direction different from that of fig. 5A in the rotational output mode of the electrotherapy apparatus 10 according to the embodiment of the present application. Fig. 5C is a schematic diagram showing the effect of electrical stimulation applied in a direction different from that of fig. 5A and 5B in the rotational output mode of the electric therapeutic apparatus 10 according to the embodiment of the present application. Fig. 6 is a circuit diagram showing a circuit included in the output switching unit 34 of the electrotherapy device 30 according to another embodiment of the present application.

As shown in fig. 1, an electrotherapy apparatus 10 according to an embodiment of the present application includes a housing 11, and first to third total three electrodes 12a, 12b, 12c mounted outside the housing 11.

The shape of the case 11 is not particularly limited, but is, for example, a round flat shape and a portable shape. The case 11 includes a control unit 13 such as a CPU (Central Processing Unit: central processing unit) for controlling the whole and an output switching unit 14 connected to the first to third electrodes 12a, 12b, 12c. The control unit 13 is directly connected to the output switching unit 14, and is connected thereto via the output adjusting unit 15. The control unit 13 is connected to a power supply control unit 16 that converts electric power obtained from the battery 17 and transmits electric power to the control unit 13, and functions as a power supply suitable for the control unit 13, and to an input device 18. In the present embodiment, the battery 17 is used as the power supply source, but an AC adapter may be used, and an industrial power source may be used as the power supply source, or power may be supplied by other methods. In addition, "connected" in the present application means electrically connected.

The input device 18 includes four push switches, i.e., a power switch 18a for turning on/off the power supply, a mode selection switch 18b for switching an operation mode such as an alternate output mode or a rotational output mode, and output intensity switches 18c and 18d for increasing or decreasing the output voltage. The input device 18 is located outside the housing 11 so as to be operable by a user. Although the electrotherapy apparatus 10 according to the embodiment of the present application is configured by four push-button switches, an input unit for controlling such additional functions may be provided in the case of providing the additional functions. For example, in the case of providing a warming means for warming the body in contact with the body in addition to the administration of the electrical stimulation, a warming selection switch for turning on/off a warming drive circuit for controlling such a warming means may be provided.

The control unit 13 is electrically connected to a power display LED19 provided on the outer surface of the housing 11 to be turned on/off in response to the on/off of the power supply. Further, a liquid crystal display device may be provided to show the current state of the electrotherapy apparatus such as the remaining power, the mode, and the intensity of output.

As shown in fig. 2A, the output switching unit 14 is configured by a total of three switching circuits 20a, 20b, and 20c provided corresponding to the three electrodes 12A, 12b, and 12c. In addition, each of the three switching circuits 20a, 20b, 20c includes two transistors and three resistors. That is, the output switching unit 14 includes six transistors 21a, 21b, 21c, 22a, 22b, 22c, and nine resistors 23a, 23b, 23c, 24ab, 24ac, 24ba, 24bc, 24ca, 24cb as a whole. In the present embodiment, the switching circuit is a circuit element group enclosed by a broken line in fig. 2A, but the switching circuit has a function of switching the potential of the corresponding electrode between the output potential outputted from the output adjustment unit 15 and the reference potential in accordance with a signal from the control unit 13. In the present application, each resistor is described as one element for convenience, but the resistor may be a plurality of resistor elements connected in series and/or parallel, or may be a variable resistor for adjusting the resistance value. In the present embodiment, the switching circuit is mounted by a printed circuit board, but may be mounted by other methods. In addition, other electronic components such as capacitors and resistors may be added, for example, according to the necessity of mounting such as reducing signal noise.

In this embodiment, a bipolar transistor is used as the transistor, but other types of transistors such as an FET (field effect transistor) may be used. That is, when an FET is used instead of a bipolar transistor, the term "collector" of the bipolar transistor corresponds to the drain of the FET. Similarly, the emitter of the bipolar transistor corresponds to the source of the FET and the base of the bipolar transistor corresponds to the gate of the FET. In the present application, the terminals corresponding to the upstream side when a current flows through the transistor, such as the collector of an NPN bipolar transistor, the drain of an n-type FET, the emitter of a PNP bipolar transistor, and the source of a p-type FET, are collectively referred to as upstream side terminals. Similarly, a terminal corresponding to a downstream side when a current flows through the transistor, such as an emitter of an NPN-type bipolar transistor, a source of an n-type FET, a collector of a PNP-type bipolar transistor, and a drain of a p-type FET, is collectively referred to as a downstream side terminal. The terminal of the control transistor such as a base or a gate that controls the amount of current flowing from the upstream side terminal to the downstream side terminal or the switching between the on state and the off state according to the current flowing or the potential applied is collectively referred to as a switch terminal. The reason why the switch terminal is referred to here is that a transistor is mainly used as a switching element for switching an on state and an off state.

Each of the switch circuits is configured as follows. The first switch circuit 20a is described below, but the same applies to the second and third switch circuits 20b and 20 c. The collector of the first transistor 21a as NPN is connected to the electrode 12a, and the emitter is connected to the (frame) ground. In the present embodiment, the ground is set to the reference potential, but other potentials may be set as the reference. The base of the first transistor 21a is connected to one of the terminals provided for each switching circuit by the control unit 13. The control unit 13 can change the electric potential of the base of the transistor 21a and change the current flowing between the base and the emitter, thereby switching the on state and the off state of the first transistor 21 a. In the present embodiment, the potential applied to the base is designed to be a value sufficiently similar to the potential of the collector-emitter of the transistor 21a in accordance with the type of the transistor in the on state. Therefore, although the reference potential of the electrode 12a is strictly different from the reference potential (frame ground) of the entire circuit, both potentials can be treated as the same potential as an explanation of the operation of the circuit of the output switching section 14 of the present embodiment.

The switching circuit 20a includes a PNP type second transistor 22a having characteristics opposite to those of the first transistor 21 a. The collector of the second transistor 22a is connected to the electrode 12 a. The emitter of the second transistor 22a is connected to a terminal of the output intensity adjusting unit 15. The base of the second transistor 22a is connected to the terminal of the output intensity adjusting section and the emitter of the second transistor 22a via the first resistor 23 a. The base of the second transistor 22a is connected to the collector of the first transistor 21b of the second switch circuit 20b via a second resistor 24ab arranged in correspondence with the second switch circuit 20 b. The base of the second transistor 22a is connected to the collector of the first transistor 21c of the third switch circuit 20c via another second resistor 24ac arranged in correspondence with the third switch circuit 20 c. That is, the second resistor is provided in plural numbers corresponding to the other switching circuits. Therefore, the base of the second transistor 22a is connected via the second resistors 24ab, 24ac to the collector of the first transistor of the other switching circuit.

As described above, the first switch circuit 20a has the same configuration as the second and third switch circuits 20b and 20 c. As a result, for example, the emitter of the second transistor 22 of each switching circuit 20 is shared and connected to the terminal of the output intensity adjusting unit 15, and the bases of the second transistors 22 of each switching circuit are connected to the collectors of the first transistors 21 of the other switching circuits via the second resistor 24.

The output intensity adjuster 15 defines an output to the electrode 12. From the viewpoint of therapeutic effects, for example, the output intensity adjusting unit 15 outputs a pulse wave, typically having a voltage of 30V at a minimum and 60V at a maximum, a frequency of 2Hz to 120Hz, and a pulse width of 100 μs to 250 μs. The voltage of the output intensity adjusting unit 15 can be changed every 10V in response to a signal from the CPU13 controlled by the input switches 18c and 18 d. In the present embodiment, only the voltage may be changed, but an input switch may be added, and the frequency and pulse width may be changed.

When one electrode is set to the reference potential, the output switching unit 14 can set the other electrode to a potential (output potential) corresponding to the output from the output adjusting unit 15. The case where the first electrode 12a is set to the reference potential and the second electrode 12b and the third electrode 12c are set to the output potential will be described below, but the same circuit operation is performed when the second or third electrodes 12b and 12c are set to the reference potential and the other electrodes are set to the output potential. The control unit 13 controls the potential of the base of the first transistor 21a of the first switch circuit 20a to be high, turns on the first transistor 21a, and sets the first electrode 12a to be a reference potential. On the other hand, the bases of the first transistors 21b, 21c of the second and third switching circuits 20b, 20c are controlled to control the first transistors to be in an off state.

The collector of the first transistor 21a of the first switching circuit 20a is connected to the second resistor 2 via the first resistor 23b of the second switching circuit 20b4ba generates a potential difference with the output intensity adjusting section 15, and a current flows as indicated by an arrow a in fig. 2B. As a result, the potential of the base of the second transistor 22b of the second switching circuit 20b is lower than the potential of the output intensity adjusting section 15, and a potential difference (V _EB ) And transistor 22b is in an on state. In other words, the resistance values of the first resistor 23b and the second resistor 24ba need to be defined such that when the transistor 21a is at the reference potential, the second transistor 22b of the second switch circuit 20b is turned on due to the potential difference generated between the base and the emitter of the transistor 22 b. Further, since the potential difference generated between the base and the emitter is based on not only the first resistor and the second resistor but also the output potential of the output intensity adjusting unit 15, it is necessary to select the transistors and define the resistance values of the first and second resistors so that the second transistor is turned on regardless of the value of the output potential within a settable potential range. When the second transistor 22B of the second switching transistor 20B is turned on, the electrode 12B becomes an output potential corresponding to the output of the output intensity adjusting unit 15 (see arrow B in fig. 2B). Strictly speaking, the potential obtained by subtracting the voltage drop between the emitter and collector of the second transistor 22b from the potential of the output intensity adjustment unit 15 becomes the potential of the electrode 12b, but the resistance values of the first and second resistors can be adjusted, the amount of current flowing between the emitter and base of the second transistor 22b can be adjusted, and the potential difference between the emitter and collector in the on state can be made small, so that the potential of the electrode 12b can be handled as the output potential in the circuit operation of the output switching unit 14 in the present embodiment. In the third switching circuit 20c, the same operation as in the second switching circuit 20b is performed, so that the electrode 12c becomes an output potential corresponding to the output of the output intensity adjusting section 15.

On the other hand, in the second transistor 22a of the first switch circuit 20a, no potential difference is generated between the emitter and the base, and the second transistor is turned off. This is because the emitter of the second transistor 22a is at the potential of the output intensity adjustment unit, and the electrodes 12b and 12C are also at the potential of the output intensity adjustment unit, so the base of the transistor 22a located therebetween is also at the potential of the output intensity adjustment unit (see arrow C in fig. 2C). Therefore, even when the first transistor 21a is set to the on state, the second transistor 22a is in the off state, so that the output intensity adjusting section 15 is not short-circuited to the ground line. Therefore, the control section 13 can automatically bring the second transistor 22 into a state suitable for the output of the electrode by controlling only the on/off state of the first transistor 21, without controlling the second transistor 22 by the control section. Therefore, the command provided in the control unit is simplified, the memory amount can be reduced, and the electronic components can be reduced.

As described with reference to fig. 2, by setting both electrodes to output potentials and setting one electrode to a reference potential, electrical stimulation can be applied to the body 1 over a wide range as shown in fig. 3. That is, by disposing three electrodes at the positions of the apexes of the substantially regular triangle, the current output from the two electrodes flows toward the remaining one electrode, so that the user can receive electric stimulation in and around the triangle formed by the electrodes, and the therapeutic effect can be improved. Therefore, the constitution in which three electrodes are used and two electrodes are set to output potentials and one electrode is set to a reference potential as shown in fig. 3 is suitable for an electrotherapy apparatus in that electric stimulation can be applied to a wide range of the body. In the present embodiment, the three electrodes 12a, 12b, 12c are fixed to the case 11, but the positions of the electrodes may be changed in accordance with the size and/or the use position of the body of the user although they are positioned outside the case 11, or the electrodes may be connected to the case via wires extending from the case, so that the user brings the electrodes into contact with the favorite positions of the body.

In addition, although a bipolar transistor is used as the first transistor 21 in the electrotherapy apparatus 10, an FET is preferably used. By using the FET, current does not flow from the CPU to the first transistor, so that power consumption can be reduced, and output of current from the CPU is not required, so that the CPU can select an inexpensive device, or an additional circuit for supplying current can be unnecessary.

In the electrotherapy apparatus according to the embodiment of the present application, the control unit 13 can apply various types of electrical stimulation by switching the first transistor to the on state at regular time intervals. That is, after the use of the electrotherapy device, when a certain time has elapsed, the control unit 13 can change the direction of the current passing through the body by turning off the first transistor in the on state and turning on the other first transistors, thereby changing the electrode that is set to the reference potential.

Fig. 4 is a schematic diagram showing the effect of electrical stimulation in the alternate output mode of the electrotherapy apparatus according to the embodiment of the present application. The alternate output mode refers to a mode in which two electrodes among the plurality of electrodes are alternately made to be reference electrodes and electrical stimulation is given to the body. In the alternating output mode, first, the control unit 13 sets the potential of the second electrode 12b to the reference potential (that is, sets the first transistor 21b of the second switching circuit 20b to the on state), and sets the potentials of the first and third electrodes 12a and 12c to the output potential, so that a current flows from the first and third electrodes 12a and 12c to the second electrode 12b in the body 1. Next, for example, when a predetermined time such as two seconds elapses, the potential of the second electrode 12b is set to the output potential, the third electrode 12c is set to the reference potential, and a current is caused to flow from the first and second electrodes 12a and 12b to the third electrode 12c. When a predetermined time has elapsed, the second electrode is set to the reference potential again, the third electrode is set to the output potential, and a current flows from the first and third electrodes 12a and 12c to the second electrode 12 b. By repeating such an operation, the user can alternately feel the electrical stimulation. For example, by receiving electric stimulation such as left and right, treatment or training can be performed to balance left and right muscles well.

Fig. 5 is a schematic diagram showing the effect of electrical stimulation in a rotational output mode of an electrotherapy apparatus according to an embodiment of the present application. The rotation output mode is one of modes of the electrode changing to the reference potential due to the passage of time, and when the direction of the current flowing through the body is indicated by an arrow, the mode in which such an arrow is changed in a rotating manner is referred to (see fig. 5A, B and C). In one embodiment of the rotary output mode, the control unit 13 causes the electric potential of the first electrode 12a to be the reference electric potential and causes the second and third electrodes 12b and 12c to be the output electric potential, so that electric current flows from the second and third electrodes 12b and 12c to the first electrode 12a, thereby giving electrical stimulation to the body (see fig. 5A). When a predetermined time has elapsed, the control unit 13 sets the potential of the second electrode 12B to the reference potential and sets the potentials of the first and third electrodes 12a and 12c to the output potential, so that the electric current flows from the first and third electrodes 12a and 12c to the second electrode to give the body electric stimulation (see fig. 5B). After a certain period of time has elapsed, the control unit 13 sets the third electrode 12C to the reference potential, sets the potentials of the first and second electrodes 12a and 12b to the output potential, and applies electrical stimulation to the body (see fig. 5C). Thereafter, the same control may be performed so that the electrode to be the reference potential is repeatedly changed to the first electrode, the second electrode, the third electrode, the first electrode, the second electrode, and the third electrode …, or the electrode to be the reference potential may be repeatedly changed to the first electrode, the second electrode, the third electrode, the first electrode, the third electrode, the second electrode, the first electrode, and the second electrode … so that the rotation direction is alternately performed. When the direction of the current applied to the body is changed in three directions in this way, the rotation of the electric stimulus is perceived in the abdomen of the user. Thus, the intestinal tract activity of the user becomes active, and an effect of eliminating constipation, cold and the like can be expected. In addition, the effects of improving urinary incontinence and the like, improving lumbago, training muscles and the like can be expected.

The user can switch the modes by pressing the mode selection switch 18b, but each parameter of the output pulse wave output from the output intensity adjustment unit 15 may be automatically set to a value suitable for each output mode in cooperation with the switching of the modes.

Fig. 6 is a circuit diagram of the output switching unit 34 according to another embodiment of the present application. This embodiment includes four electrodes 32a, 32b, 32c, 32d. The output switching unit 34 includes four switching circuits 40a, 40b, 40c, and 40d corresponding to the electrodes, but the other portions are the same as those in the embodiment shown in fig. 1.

The first switch circuit 40a will be described below, but any switch circuit has the same configuration including two transistors and four resistors. The first transistor 41a is an NPN type, and has a collector connected to the electrode 32a and an emitter electrically connected to a reference potential (frame ground). One of the terminals of the control unit 33 is connected to the base, and the on state and the connection state of the first transistor 41a are switched by controlling the potential of the base. The second transistor 42a is a PNP type transistor having a polarity different from that of the first transistor 41a, and the collector is connected to the electrode 32 a. The emitter of the second transistor 42a is connected to the output of the output intensity adjusting unit 35. The base and the emitter are connected via a first resistor 44 a. The three second resistors 44ab, 44ac, 44ad are arranged corresponding to the other switch circuits 40b, 40c, 40 d. Each of the second resistors 44ab, 44ac, 44ad is connected to the base of the second transistor 42a of the first switching circuit 40a and the collectors of the first transistors 41b, 41c, 41d of the corresponding other switching circuits 40b, 40c, 40 d.

As described above, the first switch circuit 40a has the same configuration as the second, third, and fourth switch circuits 40b, 40c, and 40 d. For example, the emitter of the second transistor 42 of each switching circuit 40 is shared and connected to the terminal of the output intensity adjusting section 35. The base of the second transistor 42 is also shared by the first resistor 43 and is connected to a terminal of the output intensity adjusting unit 15. The bases of the second transistors 42 are connected to the collectors of the first transistors 41 of the other switching circuits 40 via second resistors 44.

The operation of the output switching unit 34 is the same as that of the embodiment shown in fig. 1, and the following description will be made schematically. The control unit 33 turns on one of the four first transistors 41a, 41b, 41c, and 41d each having a collector connected to each electrode, and sets the potential of the electrode connected to the first transistor in the on state to a reference potential. At this time, since the collector side of the first transistor in the on state is set to the reference potential, the output voltage of the output regulator 35 is applied to the first resistor and the second resistor of the other switching circuit. In this way, current flows from the output adjustment unit 35 through the first resistor and the second resistor of the other switching circuit to the collector of the first transistor in the on state. Such a current finally flows through the collector-emitter of the first transistor in the on state and through a reference potential (Frame ground). When a current flows as described above, a voltage drop occurs in the first resistor of the other switching circuit, so that a potential difference occurs between the base and the emitter of the second transistor of the other switching circuit, and the second transistor is turned on. On the other hand, in the switching circuit in which the first transistor is in an on state, the second transistor is in an off state. This is because both ends of the first resistor and the second resistor are at the output potential, and a potential difference is not generated between the base and the emitter of the second transistor, which causes the transistor to be in an on state. Therefore, the control unit 33 determines the on state and the off state of the second transistor without performing another control by determining one first transistor to be turned on and the other three first transistors to be turned off. The electrode connected to the collector of the first transistor in the on state is set to the reference potential, and the remaining electrode is set to the output potential.

The embodiment including the circuit shown in fig. 2 and the embodiment including the circuit shown in fig. 6 are the same in that one of the plurality of electrodes is set to a reference potential and the other electrode is set to an output potential. The switching circuits corresponding to the number of electrodes included in the output switching section have the same configuration in both embodiments. That is, the switching circuit includes two transistors, a first resistor disposed between a base and an emitter of the second transistor, and a second resistor connecting a base of the second transistor of one switching circuit and a collector of the first transistor of the other switching circuit to each other. Therefore, although the embodiment having three or four electrodes is shown, the present application can be applied to an electrotherapy device having two or more electrodes if the output switching unit having the same number of switching circuits as the number of electrodes is used. In this case, each of the switching circuits includes two transistors, one first resistor, and one second resistor less than the number of electrodes, and the configuration of the switching circuit is the same as that of the switching circuits shown in fig. 2 and 6. The relationship between the switching circuits is similar to the switching circuits shown in fig. 2 and 6, in that the second resistor connects the base of the second transistor of one switching circuit to the collector of the first transistor of the other switching circuit. By changing the number of electrodes, more complicated electrical stimulation can be given, and on the other hand, the present application can simplify control of switching of outputs, can realize mounting based on inexpensive electronic components, and can reduce the number of components.

While the present application has been illustrated and described with respect to the specific embodiments, the present application is not limited to the illustrated embodiments, and the scope of the present application is determined only by the claims.

Claims (8)

1. An electric therapeutic apparatus for applying electric stimulation to muscles in a body, comprising:

a plurality of electrodes in contact with the body;

a control unit;

an output intensity adjusting unit for outputting a predetermined voltage to the output terminal; and

a plurality of switching circuits respectively corresponding to the plurality of electrodes,

each of the plurality of switching circuits includes:

a first transistor including a first upstream terminal electrically connected to a corresponding electrode, a first downstream terminal electrically connected to a reference potential, and a first switch terminal electrically connected to the control unit and determining an on state and an off state according to a voltage set by the control unit;

a second transistor including a second upstream side terminal connected to the output terminal, a second downstream side terminal connected to the electrode and the first upstream side terminal, and a second switch terminal for determining an on state and an off state according to a voltage, the second transistor having a characteristic opposite to that of the first transistor;

a first resistor having one end connected to the output terminal and the other end connected to the second switch terminal; and

the second resistor is at least one second resistor disposed corresponding to each other switching circuit, one end of the second resistor is connected to the second switching terminal, the other end of the second resistor is connected to the first upstream side terminal of the corresponding other switching circuit,

the control unit is configured to turn on one of the first transistors of the plurality of switching circuits and turn off the remaining first transistors of the plurality of switching circuits,

the resistance value of the first resistor and the resistance value of the second resistor are determined so that the second transistor is turned on when one of the first transistors of the other switching circuits is turned on.

2. The electrotherapy device according to claim 1, wherein,

the first transistor is a FET.

3. An electrotherapy device as claimed in claim 1 or claim 2,

the number of the plurality of electrodes is three.

4. The electrotherapy device according to claim 3, wherein,

three of the electrodes are fixed to the outside of the electrotherapy apparatus in such a manner as to be located at the apexes of the regular triangle.

5. An electrotherapy device as claimed in claim 1 or claim 2,

the number of the plurality of electrodes is four.

6. The electrotherapy device according to any one of claims 1, 2 and 4,

the control unit sequentially switches the first transistors in an on state at regular time intervals.

7. The electrotherapy device according to claim 3, wherein,

the control unit sequentially switches the first transistors in an on state at regular time intervals.

8. The electrotherapy device according to claim 5, wherein,

the control unit sequentially switches the first transistors in an on state at regular time intervals.