JPH0353950B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to an electric potential treatment device.

[Prior Art] In general, an electric potential treatment device has the following characteristics, as shown in FIG. 4a.
Secondary output terminal (output port) 2 of step-up transformer 22
The electric bed 24 connected to the electric field 3 is kept in a well insulated state with respect to the ground, and the patient 25 to be treated stands on this electric bed 24 for use. However,
As shown in FIG. 4b, the secondary output terminal 23 of the step-up transformer 22 is connected to ground on the primary side of the step-up transformer 22 via a circuit 26 that connects the terminal on the opposite side and the primary side terminal. On the other hand, on the secondary side of the step-up transformer 22, the electric bed 24 and the ground are electrically capacitively connected, and the electric bed 24 and the patient 25 sitting on it, and the patient 25 and the earth are connected. Both are considered to be electrically capacitively connected. Therefore, electric bed 2
If the insulation between 4 and the ground is insufficient, current will flow from the electrical bed 24 to the ground via the capacitor Ca, and from the ground through the connection circuit 26 to the electrical bed 24, and at the same time, current will flow from the electrical bed 24 through the capacitor Cb to the ground. Current flows through the circuit that reaches the therapist 25, passes through the capacitor Cc, and connects to the ground, causing the current to flow to the electric bed 24 and the patient 25. If this current flows excessively, it may cause serious damage. Conventionally, a resistor Ra with a large resistance value was inserted into the secondary output circuit of the step-up transformer 22 to prevent this from happening.

[Problems to be solved by the invention] However, such conventional methods have been met with resistance.
The larger the resistance value of Ra, the less current will flow, and even if the insulation between the electric bed 24 and the ground is insufficient, current will not flow excessively to the electric bed 24 and the patient 25, ensuring safety. On the other hand,
The larger the resistance value, the larger the voltage drop due to the resistor Ra, and the predetermined voltage level will no longer be generated at the output port 23. Therefore, it is difficult to ensure safety and ensure the output level at the same time. However, this is extremely difficult, especially in cases where high-level output is required. moreover,
Regardless of the magnitude of the resistance value, there have been various problems such as, if the resistance Ra were to be even partially shot, it would inevitably pose a serious danger to the person to be treated 25.

The purpose of this invention is to solve the problems of the conventional devices mentioned above and provide an electric potential therapy device that can ensure the safety of the patient at any time while ensuring a predetermined output level. It is.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a connection circuit that connects a terminal on the secondary side of a step-up transformer opposite to the output terminal and a terminal on the primary side via a resistor. A potential treatment device comprising: a detection circuit that operates when a current exceeding a predetermined level flows through the connection circuit; and a control circuit that switches the output to "L" according to an operation signal of the detection circuit. A cutoff circuit includes a relay and a relay contact that cuts off the primary side circuit of the step-up transformer when the output of the control circuit is "L", and the output of the control circuit switches from "L" to "H" by closing the cutoff circuit. The present invention is characterized in that it is provided with a delay circuit that delays the output from the detection circuit based on the instantaneous current of the connection circuit from being directly applied to the control circuit when the current is applied to the control circuit.

[Function] By employing the above means, this invention immediately cuts off the output and eliminates the danger when a situation that may pose a danger to the patient, such as insufficient insulation between the electric bed and the ground, occurs. This will prevent this from happening.

[Example] Hereinafter, an example of the present invention shown in the drawings will be described.

FIG. 1 shows an embodiment of the present invention, in which 1 is a main switch, 2 is a step-up transformer, 3 is an output terminal (output port) provided on the secondary side of the step-up transformer 2 via a resistor _R1 , and 4 is a step-up transformer. is an electric bed connected to the output terminal 3, and 5 is a treated person riding on the electric bed 4. 6 is a connection circuit that connects the terminal on the secondary side of the step-up transformer 2 opposite to the output terminal 3 and the terminal on the primary side via resistors R ₂ and R ₃ , where the resistors R ₂ and R ₃ are Both have extremely small resistance values compared to resistor _R1 . 7 is caused by the fact that when a current exceeding a predetermined level flows through the connecting circuit 6, the transistor _Q1 becomes conductive near the peak of the sine wave current due to the potential difference generated across the resistor _R2 . The operating level of the detection circuit 7 (i.e., the transistor
The conduction level of _Q1 ) can be adjusted arbitrarily using a semi-fixed resistor _R4 . 8 is the detection circuit 7
9 is a rectifier power supply circuit, 10 is a control circuit, and 11 is an energization switch. In the initial state of the control circuit 10, both the reset input and the output are in the "L" state, so the transistor _Q6 is non-conductive (the transistors _Q1 , _Q2 ,
(Q ₃ , Q ₄ are non-conducting, transistor Q ₅ is conducting) Since no current flows through relay coil switches to "H", transistor Q ₆ becomes conductive (transistors Q ₁ , Q ₂ , Q ₃ , Q ₄ , Q ₅ are non-conductive), current flows through relay coil X, and relay contact Y closes. The step-up transformer 2 is energized, and when the energization switch 11 is pressed once more, the output is switched to "L", which causes the transistor Q ₆ to become non-conductive (transistors Q ₁ ,
Q ₂ , Q ₃ , Q ₄ are non-conducting, transistor Q ₅ is conducting)
No current flows through the relay coil X, the relay contact Y opens, and the step-up transformer 2 is de-energized.In this way, each time the energizing switch 11 is pressed, the output is switched and the step-up transformer 2 is switched between energized and de-energized. It's summery. Furthermore, when the output of the control circuit 10 is switched from "L" to "H" by pressing the energizing switch 11, the capacitor C ₁ and the resistor R ₅ are connected to the connection circuit 6 until several cycles have passed from the moment the relay contact Y closes. Since an instantaneous current larger than the specified current flows, this is to delay the switching of transistor Q ₅ from conduction to non-conduction during this period to prevent transistors Q ₃ and Q ₄ from becoming conductive due to this instantaneous current. .

In the electric potential treatment device described above, when the output of the control circuit 10 is in the "H" state, the relay contact Y is closed, and the step-up transformer 2 is energized, the electric bed 4 connected to the output terminal 3 is connected to the ground. If maintained in a good insulated state, a predetermined output voltage will appear on the electric bed 4, so that the patient 5 sitting on the electric bed 4 will be treated with the electric potential. In this state,
If a current exceeding a predetermined level flows through the connection circuit 6 for some reason, such as insufficient insulation between the electric bed 4 and the ground, transistors Q ₁ and Q ₂ become conductive near the peak of the sine wave current. , thereby keeping transistors Q ₃ and Q ₄ conductive,
The reset input of the control circuit 10 is switched to "H". Then, the output of the control circuit 10 switches to "L", the transistor Q ₆ becomes non-conductive, the relay contact Y opens, the step-up transformer 2 becomes non-energized, the output voltage of the electric bed 4 disappears, and the transistor Q ₅ becomes non-conductive. The conductive transistors Q ₃ and Q ₄ become non-conductive and return to their initial state.

2 and 3 show other embodiments of the invention, in which similar parts to those in the embodiment of FIG. 1 are denoted by the same reference numerals. The detection circuit 7 detects that when a current exceeding a predetermined first level (for example, 1.5 mA) flows through the connection circuit 6, the transistor Q ₇ adjusted by the semi-fixed resistor R ₇ detects the voltage near the peak of the sine wave current. This is detected by conduction, and when a current exceeding a predetermined second level (for example, 5.0 mA) flows through the connection circuit 6,
Transistor Q ₁ adjusted by semi-fixed resistor R ₄ conducts near the peak of the sine wave current to detect this, and resistors R ₆ and R ₈
Both have a resistance value greater than 20 times the resistance value of resistor _R2 . The control circuit 10 is automatically reset when the main switch 1 is turned on,
As _a result, current flows in the relay coil The output is inverted and held in response to the conduction signal from the transistor Q ₂ accompanying this, so that no current flows through the relay coil X, the relay contact Y is opened, and the step-up transformer 2 is de-energized.
12 is another control circuit, 13 is a buzzer circuit, and the control circuit 12 controls the transistor Q when the detection circuit 7 detects that a current exceeding the first level flows through the connection circuit 6, and the transistor Q ₇ becomes conductive. When the buzzer circuit 13 receives the conduction signal from the control circuit ₁₂ , it generates a buzzer signal while temporarily maintaining this state (for example, 50 to 300 ms), and when the buzzer circuit 13 receives the buzzer signal from the control circuit 12, it generates a buzzer sound. It's summery.
N ₁ and N ₂ are neon light bulbs.

In this electric potential treatment device, when the main switch 1 is turned on, the control circuit 10 is automatically reset, the relay contact Y is closed, and the step-up transformer 2 is energized to enter the treatment state. In this state, if a current exceeding the first level (for example, 1.5 mA) flows through the connecting circuit 6 for some reason such as insufficient insulation between the electric bed 4 and the ground, the transistor Q ₇ , _Q8 conducts and buzzer circuit 13
generates a buzzer sound, which allows the patient 5 to be treated to recognize that a safe treatment condition is being compromised. Furthermore, connection circuit 6
When a current exceeding the second level (for example, 5.0 mA) flows through, transistors Q ₁ and Q ₂ become conductive near the peak of the sine wave current, relay contact Y opens, and step-up transformer 2 becomes de-energized, causing the voltage to drop. 4's output voltage disappears. Patient 5 explained this to a neon light bulb.
This can be recognized by the neon bulb _N2 turning off while _N1 remains lit. In this case, open the main switch 1 and check the cause of the current exceeding the second level flowing through the connected circuit 6. After removing
When the main switch 1 is turned on again, the control circuit 10 is automatically reset, the relay contact Y is closed, and the treatment state is resumed.

Note that the control circuit 10 may be provided with a reset switch that returns to the treatment state by pressing the reset switch after removing the cause of the current exceeding the second level flowing through the connection circuit 6.
In addition, it goes without saying that the present invention can be modified in various ways to the above-mentioned embodiments.

[Effects of the Invention] Since the present invention is configured as described above, it is possible to ensure the safety of the treated person while ensuring a predetermined output level, and as a result, there is no problem such as insufficient insulation between the electric bed and the ground. This has excellent effects such as being able to prevent the danger by immediately cutting off the output in the event that a situation that may pose a danger to the patient occurs.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing one embodiment of this invention, FIG. 2 is a block diagram showing another embodiment of this invention,
Figure 3 is a circuit diagram of the main part of Figure 2, Figure 4a,
FIG. 4b is an explanatory diagram of the conventional one. 1, 21... Main switch, 2, 22... Step-up transformer, 3, 23... Output terminal (output port),
4,24... Electric bed, 5,25... Treated person, 6,
26... Connection circuit, 7... Detection circuit, 8... Cutoff circuit, 9... Rectifier power supply circuit, 10... Control circuit, 11... Energization switch, 12... Control circuit, 13... Buzzer circuit.

Claims (1)

[Claims] 1. A potential therapy device comprising a connection circuit that connects a terminal on the secondary side of a step-up transformer opposite to the output terminal and a terminal on the primary side via a resistor, the connection circuit having a predetermined level. a detection circuit that operates when a current exceeding the current flows; a control circuit that switches the output to "L" based on the operation signal of the detection circuit; and a control circuit that cuts off the primary side circuit of the step-up transformer when the output of the control circuit is "L". A cutoff circuit equipped with a relay and relay contacts, and when the cutoff circuit is closed and the output of the control circuit switches from "L" to "H", the output from the detection circuit is directly applied to the control circuit due to the instantaneous current of the connected circuit. A potential treatment device characterized by being provided with a delay circuit to prevent the electric potential from being damaged.