Intermediate frequency therapeutic instrument no-load detection circuit

Abstract

The utility model discloses a no-load detection circuit of an intermediate frequency therapeutic instrument. The no-load detection circuit comprises a constant current control module, an isolation output module, a rectification module, a voltage division and primary filter circuit, a secondary filter module, a micro-control unit, a driving module, an electrode wire and an electrode slice. The output end of the micro-control unit is connected with the input end of the constant-current control module, and the input end of the rectifier module is connected to a constant-current output lead between the constant-current control module and the isolation output module; the isolation output module is used as a load for constant current output; according to the utility model, whether the electrode falls off is determined by determining whether the output is no-load through the sampling front-end feedback point A, the voltage of the point A at the input end changes along with the load change of the output end, especially in the no-load state, the voltage change of the point A is more obvious, the implementation method is ingenious, simple and effective, and the detection of whether the electrode of the output end falls off can be completed at the input end. And the problems of electric strength reduction and the like in practical application are not caused.

Description

Technical Field

[0001] The utility model relates to the technical field of detection circuits, and particularly to an idling detection circuit for a medium-frequency therapeutic apparatus. Background Technique

[0002] In the circuit of a medium-frequency therapeutic apparatus, for the consideration of user safety in use, generally, whether the output electrode falls off is detected. Once it is detected and confirmed that the electrode wire or electrode piece is detached, the output is immediately turned off or adjusted to prevent unexpected consequences caused by the voltage or current on the output electrode.

[0003] There are various load detection methods. The commonly used method at present is to add a detection circuit at the output end to detect whether the electrode is open to judge whether the electrode falls off. However, the existing detection schemes have the following problems that need to be improved:

[0004] 1. The crossing of the detection circuit wiring and the input circuit, or their common grounding, results in a reduction in electrical strength, affecting the stability and safety of the circuit;

[0005] 2. Isolation devices such as isolation transformers or optocouplers need to be used during implementation, increasing the cost.

[0006] 3. Adding a circuit at the output end will have a certain impact on the output waveform. For example, if optocouplers are connected in series for detection, the output waveform will generate crossover distortion similar to that, and the smaller the amplitude of the output waveform, the more obvious the distortion. Content of the Utility Model

[0007] The purpose of the utility model is to provide an idling detection circuit for a medium-frequency therapeutic apparatus to solve the problems put forward in the above background technique.

[0008] To achieve the above purpose, the utility model provides the following technical scheme: an idling detection circuit for a medium-frequency therapeutic apparatus, which includes a constant current control module, an isolation output module, a rectification module, a voltage division and primary filtering circuit, a secondary filtering module, a micro control unit, a driving module, an electrode wire and an electrode piece;

[0009] The output end of the micro control unit is connected to the input end of the constant current control module. The input end of the rectification module is connected to the lead between the constant current control module and the isolation output module. The output end of the constant current control module is connected to the isolation output module. The input end of the isolation output module is connected to the input end of the rectification module. The output end of the rectification module is connected to the input end of the voltage division and primary filtering circuit. The output end of the voltage division and primary filtering circuit is connected to the input end of the secondary filtering module. The output end of the secondary filtering module is connected to the input end of the micro control unit. The driving module is used to provide carrier drive to the isolation output module. The isolation output module includes a transformer for outputting an amplitude-modulated wave. The electrode wire and the electrode piece are used to transmit the amplitude-modulated wave to the human body for treatment.

[0010] Preferably, the constant current control module is configured to receive the modulation wave output by the micro control unit and provide it to the input end of the transformer in the isolation output module to provide a constant current modulation wave.

[0011] Preferably, when the electrode wire or electrode piece falls off, the output loop is disconnected, a relatively high voltage is fed back at point A of the input end, and the rectification module, the voltage division and first-stage filtering circuit, and the second-stage filtering module jointly complete the tracking of the voltage at point A and transmit it to the micro control unit in real time. When the micro control unit detects that the input voltage at point A exceeds a predetermined threshold, it immediately stops the power supply of the constant current control module to the isolation output module and shuts down the drive module.

[0012] Preferably, the rectification module includes a unidirectional diode for rectification and reverse isolation.

[0013] Preferably, the voltage division and first-stage filtering circuit provides an initial voltage for the subsequent second-stage filtering module.

[0014] Preferably, the modulation wave output by the micro control unit has a specific frequency and amplitude.

[0015] Preferably, the constant current control module includes a current detection circuit for real-time monitoring of the output current and keeping it constant.

[0016] Preferably, the drive module includes a carrier signal generation circuit for generating a drive signal to control the working state of the isolation output module.

[0017] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0018] The present utility model judges whether the electrode falls off by using the front-end feedback point A to confirm whether the output is no-load, and adopts an indirect method for detection to avoid affecting the waveform of the rear-end output. The voltage at point A of the input end changes with the change of the output end load. Especially in the no-load state, the change of the voltage at point A is more significant. The implementation method is ingenious, simple and effective. The detection of whether the electrode at the output end falls off can be completed at the input end, and problems such as the reduction of the electrical strength in practical applications will not be caused. Description of the Drawings

[0019] Figure 1 It is the circuit diagram of the no-load detection circuit of the intermediate frequency therapeutic apparatus of the present utility model.

[0020] In the figure: constant current control module M1, isolation output module M2, rectification module M3, voltage division and first-stage filtering circuit M4, second-stage filtering module M5, micro control unit M6, drive module M7. Detailed Embodiments

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0022] Please refer to Figure 1 , the present invention provides a technical solution: an idle-load detection circuit for an intermediate-frequency therapeutic apparatus. The idle-load detection circuit includes a constant-current control module M1, an isolation output module M2, a rectification module M3, a voltage division and first-stage filtering circuit M4, a second-stage filtering module M5, a micro-control unit M6, a driving module M7, electrode wires and electrode pads;

[0023] The rectification module M3 includes a unidirectional diode for rectification and reverse isolation; the voltage division and first-stage filtering circuit M4 provides an initial voltage for the subsequent second-stage filtering module M5; the modulation wave output by the micro-control unit M6 has a specific frequency and amplitude; the constant-current control module M1 includes a current detection circuit for real-time monitoring of the output current and maintaining it constant; the driving module M7 includes a carrier signal generation circuit for generating a driving signal to control the working state of the isolation output module M2.

[0024] A connection is made between the output end of the micro-control unit M6 and the input end of the constant-current control module M1. The input end of the rectification module M3 is connected to the wire between the constant-current control module M1 and the isolation output module M2. A connection is made between the output end of the constant-current control module M1 and the isolation output module M2. A connection is made between the input end of the isolation output module M2 and the input end of the rectification module M3. A connection is made between the output end of the rectification module M3 and the input end of the voltage division and first-stage filtering circuit M4. A connection is made between the output end of the voltage division and first-stage filtering circuit M4 and the input end of the second-stage filtering module M5. A connection is made between the output end of the second-stage filtering module M5 and the input end of the micro-control unit M6.

[0025] The driving module M7 is used to provide carrier drive to the isolation output module M2; the isolation output module M2 includes a transformer for outputting an amplitude-modulated wave; the electrode wires and electrode pads are used to transmit the amplitude-modulated wave to the human body for treatment. The constant-current control module M1 is used to receive the modulation wave output by the micro-control unit M6 and provide it to the input end of the transformer in the isolation output module M2 to provide a constant-current modulation wave.

[0026] When the electrode sheet falls off, the output loop is disconnected, and a relatively high voltage is fed back at point A of the input terminal. The rectification module M3, the voltage division and primary filtering circuit M4, and the secondary filtering module M5 jointly complete the tracking of the voltage at point A and transmit it to the micro control unit M6 in real time. When the micro control unit M6 detects that the input voltage at point A exceeds a predetermined threshold, it immediately stops the power supply of the constant current control module M1 to the isolated output module M2 and shuts down the drive module M7, achieving the purpose of output shutdown.

[0027] In summary, the present utility model determines whether the electrode falls off by using the front-end feedback point A to confirm whether the output is no-load, and adopts an indirect method to detect to avoid affecting the waveform of the rear-end output. The voltage at point A of the input terminal changes with the change of the load at the output terminal. Especially in the no-load state, the change of the voltage at point A is more significant. The implementation method is ingenious, simple and effective. The detection of whether the electrode at the output terminal falls off can be completed at the input terminal, and problems such as the reduction of electrical strength in practical applications will not be caused.

[0028] Although the embodiments of the present utility model have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present utility model. The scope of the present utility model is defined by the appended claims and their equivalents.

Claims

1. A no-load detection circuit for a medium frequency therapeutic apparatus, characterized in that: The no-load detection circuit includes a constant current control module M1, an isolation output module M2, a rectifier module M3, a voltage divider and a primary filter circuit M4, a secondary filter module M5, a micro control unit M6, a drive module M7, an electrode line and an electrode sheet; The output end of the microcontroller M6 is connected to the input end of the constant current control module M1, the input end of the rectifier module M3 is connected to the constant current output lead between the constant current control module M1 and the isolated output module M2, the output end of the constant current control module M1 is connected to the isolated output module M2, the input end of the isolated output module M2 is connected to the input end of the rectifier module M3, the output end of the rectifier module M3 is connected to the input end of the voltage divider and primary filter circuit M4, the output end of the voltage divider and primary filter circuit M4 is connected to the input end of the secondary filter module M5, and the output end of the secondary filter module M5 is connected to the input end of the microcontroller M6; the driving module M7 is used to provide carrier drive to the isolated output module M2; the isolated output module M2 includes a transformer for outputting an amplitude modulated wave; The electrode line input end is electrically connected to the isolation output module M2 output end; the electrode sheet is electrically connected to the electrode line output end; the electrode line and the electrode sheet are used to transmit the amplitude modulated wave to the human body for treatment.

2. The no-load detection circuit of a medium frequency therapeutic apparatus according to claim 1, characterized in that: The constant current control module M1 is used to receive the modulation wave output by the micro control unit M6 and provide it to the transformer input end in the isolation output module M2 to provide a modulation wave of constant current control.

3. The no-load detection circuit of a medium frequency therapeutic apparatus according to claim 1, characterized in that: The rectifier module M3, the voltage divider and the primary filter circuit M4 and the secondary filter module M5 constitute a voltage detection circuit, the input end of the voltage detection circuit is connected to the point A of the constant current output lead, and the output end is connected to the input end of the micro control unit M6; the micro control unit M6 is configured to stop the constant current control module M1 from supplying power to the isolated output module M2 and turn off the drive module M7 when the voltage at point A exceeds a predetermined threshold.

4. The no-load detection circuit of a medium frequency therapeutic apparatus according to claim 1, characterized in that: The rectifier module M3 includes a unidirectional diode for rectification and reverse isolation.

5. The no-load detection circuit of a medium frequency therapeutic apparatus according to claim 1, characterized in that: The voltage division and primary filtering circuit M4 provides an initial voltage for the subsequent secondary filtering module M5.

6. The no-load detection circuit of a medium frequency therapeutic apparatus according to claim 1, characterized in that: The modulation wave output by the micro control unit M6 has a specific frequency and amplitude.

7. The no-load detection circuit of a medium frequency therapeutic apparatus according to claim 1, characterized in that: The constant current control module M1 includes a current detection circuit for real-time monitoring of the output current and keeping it constant.

8. The no-load detection circuit of a medium frequency therapeutic apparatus according to claim 1, characterized in that: The driving module M7 includes a carrier signal generating circuit for generating a driving signal to control the working state of the isolation output module M2.

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