Electric pulse physiotherapy lead shedding detection circuit and detection method

Abstract

The invention discloses an electric pulse physiotherapy lead shedding detection circuit and detection method, and belongs to the field of electric pulse physiotherapy. The detection circuit comprises an H-bridge discharge module and a lead falling detection module, the lead falling detection module comprises a detection unit, a voltage amplitude limiting unit and a signal expansion unit, the voltage amplitude limiting unit and the signal expansion unit are connected into the H-bridge discharge module, and the detection unit is connected with the signal expansion unit. The voltage amplitude limiting unit can perform voltage amplitude limiting, so that the influence on the output voltage of the electric pulse is reduced; when the voltage of the electric pulse signal is reduced and cannot reach a detection threshold value, the signal expansion unit can form a small signal path, the lead falling detection range can be expanded, and the normal work of the detection unit can be ensured; according to the detection method, lead falling detection is started after a period of time is delayed after pulse output is started, the detection result can be prevented from being affected by the Miller effect, and the sensitivity and stability of lead falling detection are improved.

Description

Technical Field

[0001] The present invention belongs to the field of electro-pulse physiotherapy, and particularly relates to an electro-pulse physiotherapy lead-off detection circuit and a detection method. Background Art

[0002] The electro-pulse physiotherapy method is an innovative medical technology that can effectively simulate various techniques of traditional Chinese medicine, including pressing, massaging, pushing, grasping, kneading, rubbing, etc. These techniques are widely used in traditional Chinese medicine to promote health, relieve pain, and improve physical functions. Through the stimulation of micro electro-pulses, the human body can receive precise treatment at designated positions, such as tissues like the skin, muscles, nerves, and blood vessels. This method can not only effectively improve metabolism, relax tense muscles, but also help regulate the body fluid environment, promote blood circulation throughout the body, and help dredge the meridians, thus achieving an all-round health assistance effect.

[0003] During the process of electro-pulse physiotherapy, it is first necessary to accurately attach the lead electrode patches to the skin surface (load) of the patient. These electrode patches are controlled by a controller and continuously emit micro electro-pulses to stimulate the set positions. Although this process is efficient, the lead electrode patches may fall off during use due to movement or other reasons, which will undoubtedly affect the treatment effect. Therefore, physiotherapy products usually detect lead-off through circuit design.

[0004] In the prior art, electro-pulse discharge usually uses a series resistor Rd to detect lead-off. When the load impedance Rload is relatively small and does not satisfy the condition Rd << Rload, at this time, Rd will consume a large part of the power, resulting in a decrease in the power input to the load Rload and affecting the output power of the electro-pulse of the product. Summary of the Invention

[0005] To solve the above problems, the primary object of the present invention is to provide an electro-pulse physiotherapy lead-off detection circuit that can reduce the impact of lead-off detection on the output power of the discharge pulse;

[0006] Another object of the present invention is to provide an electro-pulse physiotherapy lead-off detection circuit and a detection method that can improve the sensitivity and stability of lead-off detection.

[0007] Another object of the present invention is to provide an electro-pulse physiotherapy lead-off detection method that can control the electro-pulse currents of each lead not to affect each other, limit the electro-pulse discharge current to flow only between the positive and negative electrodes of each lead, and can avoid the current flowing through the human body in an unexpected path when multiple electro-pulses are simultaneously applied to the human body, improving the safety of product use.

[0008] To achieve the above objects, the technical solution of the present invention is as follows:

[0009] The present invention provides an electric pulse therapy lead-off detection circuit, comprising: an H-bridge discharge module and a lead-off detection module. The lead-off detection module comprises a detection unit, a voltage limiting unit and a signal expansion unit. The voltage limiting unit and the signal expansion unit are connected to the H-bridge discharge module, and the detection unit is connected to the signal expansion unit.

[0010] Furthermore, the voltage limiting unit includes a diode D17 and a diode D19, the diode D17 and the diode D19 are connected in series, and one end of the diode D17 away from the diode D19 is connected to the H-bridge discharge module, and one end of the diode D19 away from the diode D17 is grounded.

[0011] Furthermore, the signal expansion unit includes a resistor R136 and a resistor R139, the resistor R136 and the resistor R139 are connected in series, and one end of the resistor R136 away from the resistor R139 is connected to the H-bridge discharge module, and one end of the resistor R139 away from the resistor R136 is grounded.

[0012] Furthermore, the detection unit includes a transistor Q30, a first electrode of the transistor Q30 is connected to a common end of the resistor R136 and the resistor R139, a second electrode outputs an IO_CHn_EXIT signal, and a third electrode is grounded.

[0013] Further, the H-bridge discharge module includes transistor Q13, transistor Q15, transistor Q23, and transistor Q24, a first load access point CHn+ is arranged between the transistor Q13 and the transistor Q23, a second first load access point CHn- is arranged between the transistor Q15 and the transistor Q24, forming an H-shaped discharge structure, and the transistor Q23, the transistor Q24, the diode D17, and the resistor R136 are interconnected to form a common end.

[0014] Furthermore, the electric pulse therapy lead fall-off detection circuit also includes a control module, which includes a first control unit, a second control unit, a third control unit, and a fourth control unit. The first control unit is connected to the transistor Q13, the second control unit is connected to the transistor Q15, the third control unit is connected to the transistor Q23, and the fourth control unit is connected to the transistor Q24.

[0015] Furthermore, the first control unit includes a resistor R110, a resistor R113, a resistor R118, and a transistor Q19, one end of the resistor R110 is connected to the transistor Q13, and the other end is connected to the transistor Q19, the resistor R113 and the resistor R118 form a common end connected to the transistor Q19, and the end of the resistor R113 away from the transistor Q19 is connected to the control signal, and the end of the resistor R118 away from the transistor Q19 is grounded.

[0016] Furthermore, the second control unit includes a resistor R109, a resistor R112, a resistor R117, and a transistor Q17, one end of the resistor R109 is connected to the transistor Q15, and the other end is connected to the transistor Q17, the resistor R112 and the resistor R117 form a common end connected to the transistor Q17, and the end of the resistor R112 away from the transistor Q17 is connected to the control signal, and the end of the resistor R117 away from the transistor Q17 is grounded.

[0017] Further, the third control unit includes a resistor R123, a resistor R129, a resistor R133, and a transistor Q27, one end of the resistor R123 is connected to the transistor Q23, and the other end is connected to the transistor Q27, the resistor R129 and the resistor R133 form a common end connected to the transistor Q27, and the end of the resistor R129 away from the transistor Q27 is connected to the control signal, and the end of the resistor R133 away from the transistor Q27 is grounded.

[0018] Further, the fourth control unit includes a resistor R124, a resistor R131, a resistor R134, and a transistor Q28, one end of the resistor R124 is connected to the transistor Q24, and the other end is connected to the transistor Q28, the resistor R131 and the resistor R134 form a common end connected to the transistor Q28, and the end of the resistor R131 away from the transistor Q28 is connected to the control signal, and the end of the resistor R134 away from the transistor Q28 is grounded.

[0019] To solve this problem, the present invention provides a method for detecting lead detachment in electric pulse therapy, comprising the steps of:

[0020] S1: Set an initial pulse width Tpw;

[0021] S2: Set each lead pulse output position, and according to the Tpw set in step S1, set the pulse width of the Nth lead pulse output position to (N-1)*Tpw, N≥1;

[0022] S3: Set the starting position of each lead-off detection to: Tdet = (N-1)*Tpw+Tpw*α, N≥1, 0.3≤α≤1;

[0023] S4: Set each lead-off end detection position Te=N*Tpw*β, α≤β≤1 and Te>Tdet;

[0024] S5: After powering on, detect lead-off, set the count value Cnt, threshold THmax and threshold THmin, THmax is greater than THmin, and THmax and THmin are both greater than one tenth of the pulse output frequency Fpulse;

[0025] S6: Continuously count the lead status within each pulse width Tpw. If the lead is continuously connected within the Tpw time, Cnt is increased by 1, otherwise Cnt is reduced by 1. When the count value Cnt exceeds the threshold value THmax, it is judged as a lead connection; when the count value Cnt does not exceed the threshold value THmin, it is judged as a lead off.

[0026] Further, in step S1, the initial pulse width ranges from 0.005 ms to 1 ms, preferably 0.3 ms.

[0027] Furthermore, in step S5, THmax is half of the pulse output frequency Fpulse, THmin is one quarter of the pulse output frequency Fpulse, and THmax and THmin are both greater than one tenth of the pulse output frequency, which can avoid lead state disconnection or frequent changes between connections under the worst conditions.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] Firstly, the lead-off detection module of the detection circuit is provided with a voltage limiting unit and a signal expansion unit. When the voltage of the electric pulse signal increases, the voltage limiting unit can perform voltage limiting, so that the voltage drop of the lead-off detection module itself is very small, thereby reducing the influence on the output voltage of the electric pulse; when the voltage of the electric pulse signal decreases, the voltage drop of the voltage limiting unit is very small and does not reach the detection threshold. At this time, the signal expansion unit can form a small signal path, which can expand the lead-off detection range and ensure that the detection unit can work normally;

[0030] Secondly, the detection method starts the lead-off detection after a delay of a period of time after the pulse output starts, which can avoid the detection result from being affected by the Miller effect and improve the sensitivity and stability of the lead-off detection;

[0031] Finally, this detection method can control the output timing of the electrical pulses of each lead, thereby controlling the electrical pulse current of each lead to flow only between the positive and negative poles of each lead. This can prevent the unintended path current from flowing through the human body when multiple electrical pulses are applied to the human body at the same time, thereby improving the safety of product use. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is the electric pulse therapy lead-off detection circuit of this embodiment. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0034] To achieve the above object, the technical solution of the present invention is as follows:

[0035] See also Figure 1 As shown, this embodiment provides an electric pulse therapy lead-off detection circuit, including: an H-bridge discharge module, a lead-off detection module, the lead-off detection module includes a detection unit, a voltage limiting unit, and a signal expansion unit, the voltage limiting unit and the signal expansion unit are connected to the H-bridge discharge module, and the detection unit is connected to the signal expansion unit.

[0036] In the present application, the H-bridge discharge module outputs an electrical pulse signal to act on the load. When the voltage of the electrical pulse signal increases, the voltage limiting unit can perform voltage limiting, so that the voltage drop of the lead-off detection module itself is very small, thereby reducing the impact on the electrical pulse output voltage; when the voltage of the electrical pulse signal decreases, the voltage drop of the voltage limiting unit is very small and does not reach the detection threshold. At this time, the signal expansion unit can form a small signal path, which can expand the lead-off detection range and ensure that the detection unit can work normally.

[0037] Furthermore, the voltage limiting unit includes a diode D17 and a diode D19, which are connected in series, and an end of the diode D17 away from the diode D19 is connected to the H-bridge discharge module, and an end of the diode D19 away from the diode D17 is grounded.

[0038] Furthermore, the signal expansion unit includes a resistor R136 and a resistor R139, which are connected in series, and an end of the resistor R136 away from the resistor R139 is connected to the H-bridge discharge module, and an end of the resistor R139 away from the resistor R136 is grounded.

[0039] Furthermore, the detection unit includes a transistor Q30, a first electrode of the transistor Q30 is connected to the common end of the resistor R136 and the resistor R139, a second electrode outputs an IO_CHn_EXIT signal, and a third electrode is grounded.

[0040] In this application, in theory, when a load is connected, transistor Q30 is turned on, and IO_CHn_EXIT outputs a low level. When no load is connected, Q30 is turned off, and IO_CHn_EXIT outputs a high level. When the voltage of the electric pulse signal increases, since the voltage drop of the diode is very small, theoretically less than 1.4V, diodes D17 and D19 can form a voltage limiter after being connected in series, which has little effect on the output voltage of the electric pulse; when the output voltage of the electric pulse of the H-bridge discharge module decreases, the voltage drop of diodes D17 and D19 in series is very small and does not reach the detection threshold. At this time, resistors R136 and R139 form a small signal path, which can expand the lead-off detection range and ensure that the detection unit can work normally.

[0041] Furthermore, the H-bridge discharge module includes transistors Q13, Q15, Q23, and Q24. A first load access point CHn+ is provided between the transistors Q13 and Q23, and a second first load access point CHn- is provided between the transistors Q15 and Q24, forming an H-shaped discharge structure. The transistors Q23, Q24, the diode D17, and the resistor R136 are interconnected to form a common end.

[0042] Furthermore, the electric pulse therapy lead detachment detection circuit also includes a control module, which includes a first control unit, a second control unit, a third control unit, and a fourth control unit. The first control unit is connected to the transistor Q13, the second control unit is connected to the transistor Q15, the third control unit is connected to the transistor Q23, and the fourth control unit is connected to the transistor Q24.

[0043] Furthermore, the first control unit includes a resistor R110, a resistor R113, a resistor R118, and a transistor Q19. One end of the resistor R110 is connected to the transistor Q13, and the other end is connected to the transistor Q19. The resistor R113 and the resistor R118 form a common end connected to the transistor Q19, and the end of the resistor R113 away from the transistor Q19 is connected to the control signal, and the end of the resistor R118 away from the transistor Q19 is grounded.

[0044] Furthermore, the second control unit includes a resistor R109, a resistor R112, a resistor R117, and a transistor Q17. One end of the resistor R109 is connected to the transistor Q15, and the other end is connected to the transistor Q17. The resistors R112 and R117 form a common end connected to the transistor Q17, and the end of the resistor R112 away from the transistor Q17 is connected to the control signal, and the end of the resistor R117 away from the transistor Q17 is grounded.

[0045] Furthermore, the third control unit includes a resistor R123, a resistor R129, a resistor R133, and a transistor Q27. One end of the resistor R123 is connected to the transistor Q23, and the other end is connected to the transistor Q27. The resistor R129 and the resistor R133 form a common end connected to the transistor Q27, and the end of the resistor R129 away from the transistor Q27 is connected to the control signal, and the end of the resistor R133 away from the transistor Q27 is grounded.

[0046] Furthermore, the fourth control unit includes a resistor R124, a resistor R131, a resistor R134, and a transistor Q28, one end of the resistor R124 is connected to the transistor Q24, and the other end is connected to the transistor Q28, the resistor R131 and the resistor R134 form a common end connected to the transistor Q28, and the end of the resistor R131 away from the transistor Q28 is connected to the control signal, and the end of the resistor R134 away from the transistor Q28 is grounded.

[0047] In the above-mentioned electric pulse therapy lead-off detection circuit, the first phase is defined as Q15 and Q24 being turned on, and the second phase is defined as Q13 and Q23 being turned on. Since the H-bridge is a high-frequency pulse discharge, the pulse width is assumed to be (0.005ms-1ms). Even if there is no load connected (CHn+ / CHn- is the load access point), after the first phase is turned on, Q23 will be briefly turned on due to the Miller effect. At this time, the current flows from Q15 through Q23 and then through the lead-off detection circuit composed of diodes D17, D19 and resistors R136, R139, and Q30, which will cause Q30 to be briefly turned on, and IO_CHn_EXIT outputs a low level. The time is defined as Terr. If the lead-off or connection state is directly judged based on the high or low output level of IO_CHn_EXIT, it will be misjudged as connected at this time. Since the discharge pulse width of the high-frequency discharge pulse can be changed arbitrarily, it is assumed to be (0.005ms-1ms) here. From the above description, it can be seen that when the first or second phase is turned on, IO_CHn_EXIT will output a low level for a time of Terr due to the H-bridge Miller effect, thereby causing a misjudgment of lead-off detection.

[0048] In the above-mentioned electric pulse therapy lead-off detection circuit, when the device has N leads (N>1), if any one electrode of any lead is detached while the other electrode remains connected, a potential difference will be generated between the remaining leads and the lead with only one electrode detached, thereby causing a misjudgment of lead-off. What is more serious is that the potential difference between the leads will generate uncontrollable displacement current in the human body, posing unpredictable safety risks to the human body.

[0049] In order to solve the above problems, the present invention provides a method for detecting lead-off of electric pulse therapy with a controllable current loop, comprising the steps of:

[0050] S1: Set an initial pulse width Tpw;

[0051] S2: Set each lead pulse output position, and according to the Tpw set in step S1, set the pulse width of the Nth lead pulse output position to (N-1)*Tpw, N≥1;

[0052] S3: Set the starting position of each lead-off detection to: Tdet = (N-1)*Tpw+Tpw*α, N≥1, 0.3≤α≤1;

[0053] S4: Set each lead-off end detection position Te=N*Tpw*β, α≤β≤1 and Te>Tdet;

[0054] S5: After powering on, detect lead-off, set the count value Cnt, threshold THmax and threshold THmin, THmax is greater than THmin, and THmax and THmin are both greater than one tenth of the pulse output frequency Fpulse;

[0055] S6: Continuously count the lead status within each pulse width Tpw. If the lead is continuously connected within the Tpw time, Cnt is increased by 1, otherwise Cnt is reduced by 1. When the count value Cnt exceeds the threshold value THmax, it is judged as a lead connection; when the count value Cnt does not exceed the threshold value THmin, it is judged as a lead off.

[0056] Further, in step S1, the initial pulse width ranges from 0.005 ms to 1 ms, preferably 0.3 ms.

[0057] Furthermore, in step S2, through the above-mentioned setting, the output positions of each lead are staggered with each other, so as to avoid crosstalk between the detections of each lead; at the same time, when this pulse is loaded to the human body, the human body still feels that the output pulse of each lead is synchronized; and more importantly: it can effectively control the current loop of each lead output current loaded to the human body, ensuring that the output current of each lead only flows between its respective channels CHn+ and CHn-, avoiding unexpected current loops flowing through the human body and thus causing safety risks.

[0058] Further, in step S3, in principle, as long as the lead-off detection is started after a delay of a period of time after the start of pulse output, the detection result will not be affected by the Miller effect. Here, the lead-off detection start position is set to Tdet=(N-1)*Tpw+Tpw*α, N≥1, 0.3≤α≤1, that is, after each pulse starts to be output, the lead-off detection is started after a delay of Tdelay=Tpw*α, so that the detection result will not be affected by the Miller effect, thereby improving the sensitivity and stability of the lead-off detection.

[0059] Furthermore, in step S5, THmax is half of the pulse output frequency Fpulse, THmin is one quarter of the pulse output frequency Fpulse, and THmax and THmin are both greater than one tenth of the pulse output frequency, which can avoid lead state disconnection or frequent changes between connections under the worst conditions.

[0060] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An electric pulse therapy lead-off detection circuit, characterized in that: include: An H-bridge discharge module and a lead-off detection module, wherein the lead-off detection module comprises a detection unit, a voltage limiting unit and a signal expansion unit, wherein the voltage limiting unit and the signal expansion unit are connected to the H-bridge discharge module, and the detection unit is connected to the signal expansion unit.

2. The electric pulse therapy lead-off detection circuit according to claim 1, characterized in that: The voltage limiting unit includes a diode D17 and a diode D19, which are connected in series, and one end of the diode D17 away from the diode D19 is connected to the H-bridge discharge module, and one end of the diode D19 away from the diode D17 is grounded.

3. The electric pulse therapy lead-off detection circuit as claimed in claim 2, characterized in that: The signal expansion unit includes a resistor R136 and a resistor R139, which are connected in series, and one end of the resistor R136 away from the resistor R139 is connected to the H-bridge discharge module, and one end of the resistor R139 away from the resistor R136 is grounded.

4. The electric pulse therapy lead-off detection circuit as claimed in claim 3, characterized in that: The detection unit includes a transistor Q30, a first electrode of the transistor Q30 is connected to the common end of the resistor R136 and the resistor R139, a second electrode outputs an IO_CHn_EXIT signal, and a third electrode is grounded.

5. The electric pulse therapy lead-off detection circuit as claimed in claim 3, characterized in that: The H-bridge discharge module includes transistors Q13, Q15, Q23, and Q24. A first load access point CHn+ is provided between the transistors Q13 and Q23, and a second first load access point CHn- is provided between the transistors Q15 and Q24 to form an H-shaped discharge structure. The transistors Q23, Q24, diode D17, and resistor R136 are interconnected to form a common end.

6. The electric pulse therapy lead-off detection circuit as claimed in claim 5, characterized in that: The electric pulse therapy lead-off detection circuit also includes a control module, which includes a first control unit, a second control unit, a third control unit, and a fourth control unit. The first control unit is connected to the transistor Q13, the second control unit is connected to the transistor Q15, the third control unit is connected to the transistor Q23, and the fourth control unit is connected to the transistor Q24.

7. The electric pulse therapy lead-off detection circuit as claimed in claim 6, characterized in that: The first control unit includes a resistor R110, a resistor R113, a resistor R118, and a transistor Q19, one end of the resistor R110 is connected to the transistor Q13, and the other end is connected to the transistor Q19, the resistor R113 and the resistor R118 form a common end connected to the transistor Q19, and the end of the resistor R113 away from the transistor Q19 is connected to the control signal, and the end of the resistor R118 away from the transistor Q19 is grounded; The second control unit includes a resistor R109, a resistor R112, a resistor R117, and a transistor Q17. One end of the resistor R109 is connected to the transistor Q15, and the other end is connected to the transistor Q17. The resistor R112 and the resistor R117 form a common end connected to the transistor Q17, and the end of the resistor R112 away from the transistor Q17 is connected to the control signal, and the end of the resistor R117 away from the transistor Q17 is grounded.

8. The electric pulse therapy lead-off detection circuit as claimed in claim 6, characterized in that: The third control unit includes a resistor R123, a resistor R129, a resistor R133, and a transistor Q27, one end of the resistor R123 is connected to the transistor Q23, and the other end is connected to the transistor Q27, the resistor R129 and the resistor R133 form a common end connected to the transistor Q27, and the end of the resistor R129 away from the transistor Q27 is connected to the control signal, and the end of the resistor R133 away from the transistor Q27 is grounded; The fourth control unit includes a resistor R124, a resistor R131, a resistor R134, and a transistor Q28. One end of the resistor R124 is connected to the transistor Q24, and the other end is connected to the transistor Q28. The resistor R131 and the resistor R134 form a common end connected to the transistor Q28, and the end of the resistor R131 away from the transistor Q28 is connected to the control signal, and the end of the resistor R134 away from the transistor Q28 is grounded.

9. A detection method for the electric pulse therapy lead-off detection circuit according to any one of claims 1 to 8, comprising the steps of: S1: Set an initial pulse width Tpw; S2: Set each lead pulse output position, and according to the Tpw set in step S1, set the pulse width of the Nth lead pulse output position to (N-1)*Tpw, N≥1; S3: Set the starting position of each lead-off detection to: Tdet = (N-1)*Tpw+Tpw*α, N≥1, 0.3≤α≤1; S4: Set each lead-off end detection position Te=N*Tpw*β, α≤β≤1 and Te>Tdet; S5: After powering on, detect lead-off, set the count value Cnt, threshold THmax and threshold THmin, THmax is greater than THmin, and THmax and THmin are both greater than one tenth of the pulse output frequency Fpulse; S6: Continuously count the lead status within each pulse width Tpw. If the lead is continuously connected within the Tpw time, Cnt is increased by 1, otherwise Cnt is reduced by 1. When the count value Cnt exceeds the threshold value THmax, it is judged as a lead connection; when the count value Cnt does not exceed the threshold value THmin, it is judged as a lead off.

10. The detection method according to claim 9, characterized in that: In step S1, the initial pulse width ranges from 0.005 ms to 1 ms.

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