Intermittent high-voltage pulse control method, pulse circuit, and acoustic pressure therapy device

Abstract

This invention provides an intermittent high-voltage pulse control method, a pulse circuit, and an acoustic pressure therapy device. The control method includes: obtaining a charging cycle based on an operating frequency of the piezoelectric ceramic plate, where the charging cycle is longer than operating time Et of the pulse signal in the pulse generation circuit; issuing a charging command at the beginning of each charging cycle to trigger the pulse generation circuit to enter a charging state, and after charging is completed, performing discharging to release a stored energy voltage to the piezoelectric ceramic plate to complete output of the pulse signal within the current charging cycle; and after outputting the pulse signal within the current charging cycle, issuing a sleep command to stop the operation of the pulse generation circuit until a next charging cycle begins, and then issuing the charging command again to trigger the pulse generation circuit.

Description

INTERMITTENT HIGH-VOLTAGE PULSE CONTROL METHOD, PULSE CIRCUIT, AND ACOUSTIC PRESSURE THERAPY DEVICE BACKGROUND OF THE INVENTIONField of the Invention

[0001] The present invention relates to the field of electronic circuits, and in particular to an intermittent high-voltage pulse control method, a pulse circuit, and an acoustic pressure therapy device.Description of the Related Art

[0002] Piezoelectric ceramic plates are functional ceramic materials capable of bidirectionally converting mechanical energy and electrical energy. Owing to intrinsic piezoelectric effect, the piezoelectric ceramic plates can generate vibrations at different frequencies under the control of electronic circuits, thereby producing various sounds. In the medical field, piezoelectric ceramic vibration plates can be used for ultrasonic diagnosis and acoustic pressure therapy. The piezoelectric ceramic vibration plates enable non-invasive and painless diagnosis and treatment by transmitting energy into the human body through high-frequency vibrations. During acoustic pressure therapy, the piezoelectric ceramic plates are required to generate instantaneous sound pressures. Currently, high-voltage pulse generation circuits are mainly employed to deliver high- voltage pulses to the piezoelectric ceramic plates. The high-voltage pulses rapidly release stored high-voltage electrical energy (for example, within 500 ns) to the piezoelectric ceramic plates, which in turn vibrate to output instantaneous sound pressures.

[0003] To achieve the output of high-voltage pulses, it is ensured that a high-voltage capacitor has stored sufficient electrical energy to reach a required voltage threshold before each discharging. Therefore, in existing high-voltage pulse generation circuits, after high-voltage capacitors are charged, continuous replenishment charging needs to be performed before the beginning of discharging commands so as to prevent the capacitors from experiencing a voltage drop and, consequently, a reduction in stored energy. Specifically, the high-voltage pulse generation circuit remains in an operating state at all times other than during discharging. In fact, relative to an operating cycle of the piezoelectric ceramic plate, time required for a pulse signal to complete a charging-discharging cycle is extremely short. Consequently, long-term continuous replenishment charging inevitably leads to high power consumption, excessive thermal buildup,and accelerated aging of circuit components in the high-voltage pulse generation circuit, thereby significantly impacting the service life of an acoustic pressure therapy device. Further, the existing high-voltage pulse generation circuits may suffer from component damage during a charging phase, as well as from poor control accuracy of a pulse signal discharge frequency, and the like.BRIEF SUMMARY OF THE INVENTION

[0004] To overcome shortcomings of the prior art, the present invention provides a low-power intermittent high-voltage pulse control method and a circuit for an intermittent high-voltage pulse control circuit.

[0005] To achieve the above objective, the present invention provides an intermittent high- voltage pulse control method, where the control method intermittently controls a pulse generation circuit to output a pulse signal to a piezoelectric ceramic plate. The control method includes:

[0006] obtaining a charging cycle based on an operating frequency of the piezoelectric ceramic plate, where the charging cycle is longer than operating time Et of the pulse signal in the pulse generation circuit;

[0007] issuing a charging command at the beginning of each charging cycle to trigger the pulse generation circuit to enter a charging state, and after charging is completed, performing discharging to release a stored energy voltage to the piezoelectric ceramic plate to complete output of the pulse signal within the current charging cycle; and

[0008] after outputting the pulse signal within the current charging cycle, issuing a sleep command to stop the operation of the pulse generation circuit until a next charging cycle begins, and then issuing the charging command again to trigger the pulse generation circuit to re-enter the charging state.

[0009] According to one embodiment of the present invention, the pulse generation circuit is connected to an alternating current (AC) power supply, an energy storage element is charged based on AC power, with charging time being less than an AC power supply cycle, and the intermittent high-voltage pulse control method further includes:

[0010] detecting an AC power supply zero-crossing signal; and

[0011] triggering, at a first AC power supply zero-crossing point after the charging command is issued, the pulse generation circuit to enter the charging state.

[0012] According to one embodiment of the present invention, the intermittent high-voltage pulse control method further includes:

[0013] starting timing upon issuance of the charging command within each charging cycle;

[0014] monitoring a voltage across the energy storage element in the pulse generation circuit after the pulse generation circuit starts being charged;

[0015] determining whether the voltage across the energy storage element has reached a preset target voltage;

[0016] if yes, indicating that charging is completed, and completing timing to obtain charging command execution time St; and

[0017] based on the charging command execution time St and the operating time Et of the pulse signal, calculating delayed discharging control time Dt, after charging is completed, performing discharging after the delayed discharging control time Dt, and associating a discharging cycle with the charging cycle so that both have the same frequency, where the discharging control time is Dt = Et - St, and Et is the operating time of the pulse signal in the pulse generation circuit.

[0018] In addition, the present invention provides a circuit for an intermittent high-voltage pulse control method, including a pulse generation circuit and a timing control circuit. The pulse generation circuit includes an energy storage element and a discharging unit, where the energy storage element is electrically connected to a charging power supply, the discharging unit forms a discharging loop between the energy storage element and a piezoelectric ceramic plate, and within each charging cycle, the energy storage element completes one charging and one discharging to output a pulse signal. The timing control circuit is electrically connected to the pulse generation circuit. The timing control circuit controls timing of the pulse generation circuit using the above intermittent high-voltage pulse control method, to intermittently control an operating state of the pulse generation circuit within each charging cycle.

[0019] According to one embodiment of the present invention, the timing control circuit includes a high-voltage feedback unit, a high-voltage threshold detection unit, and a timing control unit. The high-voltage feedback unit is electrically connected between two ends of the energy storage element in the pulse generation circuit to detect a voltage across the energy storage element in a charging state. The high-voltage threshold detection unit includes a comparator, where the comparator determines whether the voltage detected by the high-voltage feedback circuit across the energy storage element has reached a target voltage, and outputs a charging completion signal when the target voltage is reached. The timing control unit is electrically connected to the high- voltage threshold detection circuit, where the timing control unit issues a charging command at the beginning of each charging cycle to trigger the pulse generation circuit to enter the charging state; upon receiving the charging completion signal fed back by the high-voltage threshold detection circuit, the timing control unit issues a stop command to the pulse generation circuit to stop charging; and subsequently, the timing control unit outputs a discharging signal to thedischarging unit in the pulse generation circuit to connect a discharging loop, releasing the voltage across the energy storage element through the discharging loop to the piezoelectric ceramic plate, thereby implementing output of the pulse signal within the current cycle.

[0020] According to one embodiment of the present invention, the charging power supply is an AC power supply, and the timing control circuit further includes a zero-crossing detection circuit for detecting an AC power supply zero-crossing signal; and the timing control unit triggers, at a first AC power supply zero-crossing point after the charging command is issued, the pulse generation circuit to enter the charging state.

[0021] According to one embodiment of the present invention, a timer is provided in the timing control unit, and the timing control unit triggers the timer to start timing simultaneously when issuing the charging command; the timing control unit turns off the timer upon receiving a charging completion signal to obtain charging command execution time St; and the timing control unit calculates discharging control time Dt based on the timed charging command execution time and operating time of the pulse signal, outputs the discharging signal to the discharging unit after delayed discharging control time Dt, and associates a discharging cycle with the charging cycle so that both have the same frequency, where the discharging control time is Dt = Et - St, and Et is operating time of a pulse in the pulse generation circuit.

[0022] According to one embodiment of the present invention, the timing control circuit includes a power supply switch electrically connected between the pulse generation circuit and the charging power supply, the power supply switch is electrically connected to the timing control unit, and is closed or opened respectively when the timing control unit issues the charging command and the stop command.

[0023] According to one embodiment of the present invention, the charging power supply is an AC power supply. The pulse generation circuit further includes a step-up transformer and a rectifier unit. The step-up transformer is electrically connected to the AC power supply, steps up an AC voltage, and outputs the AC voltage after step-up to the rectifier unit. The rectifier unit outputs a DC voltage to charge the energy storage element.

[0024] According to one embodiment of the present invention, the step-up transformer has at least two input terminals with different turn ratios, and the pulse generation circuit further includes a power supply switching unit electrically connected to the input terminals of the step-up transformer. The power supply switching unit includes a power supply voltage detection circuit and a selector switch, the power supply voltage detection circuit detects a voltage of the AC power supply and controls the selector switch based on the detected voltage to select an input terminal with a corresponding turn ratio on the step-up transformer.

[0025] In addition, the present invention provides an acoustic pressure therapy device including the above circuit for an intermittent high-voltage pulse control method.

[0026] In summary, in the intermittent high-voltage pulse control method and the circuit for an intermittent high-voltage pulse control method provided in the present invention, the timing control circuit issues the charging command at the beginning of each charging cycle, causing the pulse generation circuit to enter the charging state and, after charging is completed, to complete discharging, to output the pulse signal within the current charging cycle. Afterwards, the pulse generation circuit enters a standby state until the beginning of a next charging cycle, and then the pulse generation circuit is triggered again to enter the charging state. Compared with a continuous charging and replenishment approach, in the intermittent high-voltage pulse control method provided in this application, charging is performed in advance based on the operating frequency requirements of the piezoelectric ceramic plate before each pulse discharging, and a waiting state begins after the pulse discharging is completed. To be specific, within one charging cycle, the pulse generation circuit operates intermittently. This operating mode greatly reduces a frequency of charging and replenishment in the circuit, thereby significantly lowering power consumption and keeping the circuit in optimal condition.

[0027] To make the above and other objectives, features, and advantages of the present invention more obvious and understandable, the following preferred embodiments are presented in detail with reference to accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Fig. 1 is a schematic flow diagram of an intermittent high-voltage pulse control method according to an embodiment of the present invention.

[0029] Fig. 2 is a schematic flow diagram of step S30 in Fig. 1.

[0030] Fig. 3 is a timing diagram of charging an energy storage element by an AC power supply in the intermittent high-voltage pulse control method according to an embodiment of the present invention.

[0031] Fig. 4 is a schematic diagram of a charging and discharging frequency control waveform in the method shown in Fig. 3.

[0032] Fig. 5 is a schematic diagram of a principle of a control circuit for the intermittent high- voltage pulse control method according to an embodiment of the present invention.DETAILED DESCRIPTION OF THE INVENTION

[0033] A piezoelectric ceramic plate used for acoustic pressure therapy requires a high-voltage pulse generation circuit to output an instantaneous high voltage within an extremely short timeperiod to generate a sound intensity pressure required for acoustic pressure therapy. To ensure that an output voltage of the pulse generation circuit meets requirements, it is necessary to ensure that a high-voltage capacitor stores sufficient electrical energy to meet the output voltage.Therefore, an existing pulse generation circuit continuously charges a high-voltage capacitor except during a discharging period, to ensure that the high-voltage capacitor always remains in a high-voltage energy storage state to prevent a voltage drop. To be specific, the pulse generation circuit operates in a continuous supplementary charging mode, which not only consumes a lot of energy but also causes excessive heat generation and rapid aging of components.

[0034] To address this, an embodiment provides an intermittent high-voltage pulse control method that outputs a pulse voltage meeting requirements for a piezoelectric ceramic plate with low power consumption. Specifically, as shown in Fig. 1, the intermittent high-voltage pulse control method includes: obtaining a charging cycle based on an operating frequency of the piezoelectric ceramic plate, where the charging cycle is longer than operating time Et of a single pulse signal in the pulse generation circuit (step S10); issuing a charging command at the beginning of each charging cycle to trigger the pulse generation circuit to enter a charging state, and after charging is completed, performing discharging to release a stored energy voltage to the piezoelectric ceramic plate to complete output of the pulse signal within the current charging cycle (step S30); and after outputting the pulse signal within the current charging cycle, issuing a sleep command to stop the operation of the pulse generation circuit until a next charging cycle begins, and then issuing the charging command again to trigger the pulse generation circuit to reenter the charging state (step S40).

[0035] In the intermittent high-voltage pulse control method provided in this embodiment, a cycle obtained based on the operating frequency of the piezoelectric ceramic plate is the charging cycle. In the intermittent control method, charging is performed before each pulse output, and immediate discharging is performed after charging is completed, to prevent insufficient pulse output voltage due to a voltage drop. In addition, this arrangement also ensures that in each cycle, the pulse generation circuit operates only during a pulse signal generation period and remains in a waiting state at other times. Compared to continuous supplementary charging, the pulse generation circuit in the waiting state inevitably has lower power consumption, keeping the high- voltage pulse circuit in optimal condition. Specifically, a frequency of the piezoelectric ceramic plate is usually from 1 Hz to 12 Hz. The single operating cycle is 1,000 ms (to be specific, a charging cycle of the piezoelectric ceramic plate is 1,000 ms) at the lowest frequency of 1 Hz. Within the entire charging cycle, the operating time Et of the pulse signal is approximately 30 ms-40 ms, and remaining 960 ms is waiting time. The single operating cycle is 83.3 ms (to bespecific, the charging cycle is 83.3 ms) at the highest frequency of 12 Hz. Within this charging cycle, because the operating time Et of the pulse signal is still only 30 ms-40 ms, remaining 43.3 ms is still the waiting time. Therefore, regardless of the operating frequency of the piezoelectric ceramic plate, the intermittent high-voltage pulse control method ensures that the waiting time for the pulse generation circuit is longer than the operating time Et of the pulse signal, thereby greatly reducing power consumption of the pulse generation circuit within each charging cycle.

[0036] In this embodiment, the pulse generation circuit is connected to an AC power supply, and an energy storage element is charged based on AC power, with charging time being less than an AC power supply cycle. The intermittent high-voltage pulse control method provided in this embodiment further includes: step S20: detecting an AC power supply zero-crossing signal. Based on the AC power supply zero-crossing signal detected in step S20, in step S30, the pulse generation circuit is triggered at a first AC power supply zero-crossing point after a charging command is issued, to enter the charging state. This arrangement ensures voltage step-up of the high-voltage pulse generation circuit is fully controlled by the AC power supply, and a voltage of the high-voltage pulse generation circuit increases sequentially from a low value to a high value during a charging period. In this way, during each pulse charging process, a load on a high- voltage component (such as a high-voltage transformer and a rectifier unit) and a load on the energy storage element in the high-voltage pulse generation circuit increase progressively from low to high, effectively preventing the impact of an initial charging voltage on a device and greatly improving the service life of the device. In addition, this arrangement is also an optimal solution for energy consumption control. Specifically, current AC power supplies on the market are usually 100-127 Vac

[0037] / 60 Hz and 220-240 Vac / 50 Hz, corresponding to AC cycles of 16.6 ms and 20 ms, respectively. Therefore, when the pulse generation circuit is designed, the charging time of the energy storage element is set to be less than or equal to 20 ms.

[0038] Fig. 3 shows a timing diagram of charging an energy storage element by an AC power supply. In Fig. 3, an upper part is a voltage waveform of the AC power supply, and a lower part is a discharging waveform of the energy storage element when the piezoelectric ceramic plate operates at 8 Hz. As shown in Fig. 3, at a first zero-crossing point of the AC voltage (namely, at a time point tl), the high-voltage pulse generation circuit begins to charge the energy storage element. A voltage across the energy storage element continuously increases and charging is completed at a time point t2, after which discharging occurs at a time point t3 to output a pulse signal. From the start of charging at the time point tl to the end of discharging at the time point t3, operating time Et = t3 - tl of the pulse signal is approximately 30 ms to 40 ms. Afterdischarging is completed, the high-voltage pulse generation circuit stops a process, and a voltage across the energy storage element remains at a post-discharging zero level, awaiting the beginning of a next charging cycle T (namely, a time point at 125 ms after tl). At a time point tl+T, the next charging cycle begins, and a timing control circuit issues a charging command. However, at this time point, the AC power is not at a zero-crossing position. Therefore, the timing control circuit does not directly trigger the pulse generation circuit after issuing the command, but instead waits for the beginning of a first AC power supply zero-crossing signal after the command is issued. At a time point t4, upon receiving the AC power supply zero-crossing signal, the timing control circuit triggers the pulse generation circuit to enter the charging state and generate a pulse signal within time Et, and then returns to a waiting state again until a next charging cycle begins.

[0039] In the intermittent high-voltage pulse control method provided in this embodiment, a condition for triggering the pulse generation circuit is to receive the first AC power supply zerocrossing signal after a command is issued by timing control. The charging command cycle is obtained based on the operating frequency of the piezoelectric ceramic plate; and different operating frequencies result in different charging cycles. Obviously, a charging command cycle and an AC power supply cycle are not synchronized. The asynchronous cycles mean that after each charging cycle, the pulse generation circuit, upon receiving the charging command, needs to wait for a period (namely, charging waiting time Wt) before receiving the AC power supply zerocrossing signal to begin charging. The charging waiting time Wt varies for each charging cycle, as shown in Fig. 4. In the intermittent high-voltage pulse control method provided in this embodiment, after the pulse generation circuit completes charging, discharging needs to be performed as soon as possible to prevent the energy storage element from suffering from a voltage drop. Specifically, a voltage across the energy storage element can be monitored in real time through a high-voltage feedback unit and a high-voltage threshold detection unit. When the voltage across the energy storage element reaches a set pulse signal threshold voltage, the timing control circuit issues a discharging command, and the pulse generation circuit actuates the voltage across the energy storage element to form a pulse signal.

[0040] In this control method, the discharging command is based on a time point when charging of the energy storage element is completed. However, as previously described, the asynchronous charging cycle and AC power supply cycle result in varying charging waiting time Wt for each charging cycle. Therefore, within each charging cycle, a time point when the energy storage element completes charging relative to the start of the charging cycle differs, making the discharging command a non-cyclic command and unrelated to the charging command. Such acontrol method may lead to uncoordinated timing when performed. To solve this problem, in this embodiment, a discharging control time Dt is set after each charging cycle is completed, and compensation is performed on the charging waiting time Wt based on the discharging control time Dt, so that a time interval between the issuance of the charging command and the discharging command within each charging cycle is consistent. To be specific, the operating time Et of a pulse signal in the pulse generation circuit is consistent, so that a non-cyclic discharging command is associated with a cyclic charging command. Both the charging cycle and the discharging cycle can be obtained based on the same cycle derived from the operating frequency of the piezoelectric ceramic plate, thereby implementing unified coordinated timing control.

[0041] Specifically, the command control of the charging cycle can be performed entirely according to theoretical cycle time. For example, when the operating frequency of the piezoelectric ceramic plate is 8 Hz, a cycle thereof is 125 ms. Accordingly, the timing control unit issues a charging command every 125 ms and starts timing upon issuing the command (step S301). After each command is issued, the pulse generation circuit begins charging after the charging waiting time Wt (beginning of an AC power supply zero-crossing signal), and the voltage across the energy storage element in the pulse generation circuit is monitored (step S302). It is determined whether the voltage across the energy storage element has reached a preset target voltage (step S303). Once reached, it indicates charging completion, and timing is completed to obtain charging command execution time St (step S304). Specifically, the charging command execution time St is a sum of charging waiting time Wt and charging time Ct, namely, St = Wt + Ct. Based on the charging command execution time St and the operating time Et of the pulse signal, delayed discharging control time Dt is calculated, and after charging is completed, discharging is performed after the delayed discharging control time Dt (step S305); and the discharging control time Dt satisfies: Wt + Ct + Dt = Et, namely, St + Dt = Et.

[0042] In the pulse generation circuit, the pulse signal is a cyclic signal, and the operating time Et of each pulse signal is determined. As previously described, in an acoustic pressure therapy device, operating time Et of a pulse signal delivered to the piezoelectric ceramic plate is typically determined time within 30 ms-40 ms. Therefore, based on the determined operating time Et of the pulse signal and the charging command execution time St obtained after timing, Dt = Et - St is calculated for each pulse cycle. After charging is completed, the discharging command is issued after a delay of Et - St. In this way, compensation for the charging waiting time Wt is performed based on the discharging control time Dt, the discharging cycle is associated with the charging cycle, so that both have the same frequency, enabling synchronized execution of charging followed by discharging. This also ensures that a discharging frequency is controlled asaccurately as the charging frequency, maintaining the stability of a frequency of a high-voltage pulse output.

[0043] Determined operating time Et of the pulse signal within 30 ms-40 ms is used as an example for explanation in this embodiment. However, the present invention is not limited thereto. In other embodiments, the operating time Et of the pulse signal can also be adjusted based on requirements for vibration duration of the piezoelectric ceramic plate.

[0044] Corresponding to the above circuit for an intermittent high-voltage pulse control method, this embodiment further provides a circuit for an intermittent high-voltage pulse control method, including a pulse generation circuit 1 and a timing control circuit 2, as shown in Fig. 5. The pulse generation circuit 1 includes an energy storage element 10 and a discharging unit 20. The energy storage element 10 is electrically connected to a charging power supply. The discharging unit 20 forms a discharging loop between the energy storage element 10 and a piezoelectric ceramic plate 21. Within each charging cycle, the energy storage element 50 completes one charging and one discharging to output a pulse signal. The timing control circuit 2 is electrically connected to the pulse generation circuit 1. The timing control circuit 2 controls timing of the pulse generation circuit using the above intermittent high-voltage pulse control method, to intermittently control an operating state of the pulse generation circuit 10 within each charging cycle.

[0045] Specifically, as shown in Fig. 5, the timing control circuit 2 includes a high-voltage feedback unit 30, a high-voltage threshold detection unit 40, and a timing control unit 50. The high-voltage feedback unit 30 is electrically connected between two ends of the energy storage element in the pulse generation circuit to detect a voltage across the energy storage element in a charging state. Specifically, the high-voltage feedback unit 30 may be a voltage divider network including voltage divider resistors, and a variation of a voltage across the energy storage element is obtained via the voltage divider network. The high-voltage threshold detection unit 40 includes a comparator, an input terminal of the comparator is connected to an output of the high-voltage feedback unit 30 to receive a voltage on the energy storage element 10 detected by the high- voltage feedback unit 30. A reference terminal of the comparator is connected to a target voltage. The target voltage is compared with the voltage on the energy storage element 10 detected by the high-voltage feedback unit 30, so that it is determined whether the energy storage element 10 has completed charging. When the voltage on the energy storage element detected 10 by the high- voltage feedback unit 30 reaches the target voltage, a charging completion signal is output to the timing control unit 50. In this embodiment, the energy storage element 10 is an energy storage capacitor. However, the present invention is not limited thereto. In other embodiments, the energystorage element may be a series of multiple energy storage capacitors or a combination of an energy storage capacitor, an inductor, and another energy storage element.

[0046] The timing control unit 50 is electrically connected to the high-voltage threshold detection circuit 40. The timing control unit 50 issues a charging command at the start of each charging cycle to trigger the pulse generation circuit 1 to enter the charging state. Upon receiving a charging completion signal fed back by the high-voltage threshold detection circuit 40, a stop command is issued to the pulse generation circuit 1 to stop charging. Afterwards, a discharging signal is output to a discharging switch 22 in the discharging unit 20. The discharging switch 22 is closed to communicate with a discharging loop, and a voltage across the energy storage element 10 is released through the discharging loop to the piezoelectric ceramic plate 21, thereby outputting a pulse signal within a current cycle. Specifically, the timing control circuit 2 includes a power supply switch 60 electrically connected between the pulse generation circuit 1 and the charging power supply 3, and the power supply switch 60 is electrically connected to the timing control unit 50. When the timing control unit 50 issues a charging command, the power supply switch 60 is closed based on the charging command to communicate the pulse generation circuit 1 with the charging power supply 3, thereby charging the energy storage element 10. When the timing control unit 50 issues a discharging command, the discharging switch 22 is closed and the power supply switch 60 is opened, disconnecting the pulse generation circuit 1 from the charging power supply 3, so that after discharging, the pulse generation circuit 1 enters a sleep state until the beginning of a next charging cycle, thereby implementing output in the intermittent high- voltage pulse control method.

[0047] In this embodiment, the charging power supply 3 is an AC power supply. The timing control circuit 2 further includes a zero-crossing detection circuit 70 for detecting a zero-crossing signal of the AC power supply 3, which is electrically connected to the timing control unit 50. Specifically, when the charging cycle begins, the timing control unit 50 issues a charging command, but the power supply switch 60 is not immediately closed. The timing control unit 50 monitors input of the zero-crossing detection circuit 70 after issuing the charging command, and only after the zero-crossing detection circuit 70 inputs a first AC power supply zero-crossing signal does the timing control unit 50 output a signal to the power supply switch 60 to close the power supply switch, triggering the pulse generation circuit 1 to enter the charging state.Charging of the energy storage element 10 based on the zero-crossing detection circuit 70 ensures that a load on each component in the pulse generation circuit 1 gradually increases from low to high, effectively preventing the impact of high-voltage surges on the component and greatly improving circuit reliability.

[0048] A zero-crossing detection circuit with a comparator can be used for the zero-crossing detection circuit 70, where an AC voltage, after attenuation by a voltage divider resistor on the zero-crossing detection circuit, is sent to the comparator. Zero-crossing point determining of the AC voltage is performed based on a zero reference voltage. In other embodiments, a zerocrossing detection circuit with an analog-to-digital converter (ADC) can also be used. The AC voltage attenuated by the voltage divider resistor is sent to the ADC, and zero-crossing point determining is performed after ADC voltage sampling and comparison. However, the present invention does not impose any limitations on the zero-crossing detection method or a specific structure of the zero-crossing detection circuit.

[0049] As described in the above intermittent high-voltage pulse control method, due to charging of the pulse generation circuit 1 based on the AC power supply zero-crossing signal, after the charging command is issued, the power supply switch 60 is closed only after a waiting period (namely, charging waiting time Wt) to charge the energy storage element 10, and the charging waiting time Wt varies for each charging cycle. This results in discharging control of the pulse signal becoming a non-periodic command and unrelated to the charging command, which may lead to uncoordinated timing during execution. Therefore, in the control method provided in this embodiment, the charging waiting time Wt is compensated by increasing the discharging control time Dt, so that the operating time Et of each pulse signal is determined, the discharging command is associated with the charging command, and both can be periodically controlled based on an operating frequency of the piezoelectric ceramic plate. Correspondingly, in the intermittent high-voltage pulse control method circuit provided in this embodiment, a timer is provided in the timing control unit 50. The timing control unit 50 triggers a timer 51 to start timing when the charging command is issued. The timing control unit 50 stops the timer after receiving a charging completion signal to obtain charging command execution time St. Based on operating time Et of each pulse signal and the charging command execution time St obtained by the timer, discharging control time Dt is calculated as Dt = Et - St. After delayed discharging control time Dt, the timing control unit 50 outputs a discharging signal to the discharging unit 20, and associates the discharging cycle with the charging cycle, so that both have the same frequency. In this embodiment, the timing control unit 50 is an MCU, and charging command execution time St is calculated based on a timer provided by a crystal oscillator within the MCU. However, the present invention is not limited thereto. In other embodiments, the timer may alternatively be additionally provided externally to the timing control unit 50 to measure the charging command execution time St.

[0050] As shown in Fig. 4, in this embodiment, the charging power supply 3 is an AC power supply. The pulse generation circuit 1 further includes a step-up transformer 80 and a rectifier unit 90. The step-up transformer 80 is electrically connected to the AC power supply 3, steps up an AC voltage, and outputs the AC voltage after step-up to the rectifier unit 90. The rectifier unit 90 outputs a DC voltage to charge the energy storage element 10. The step-up transformer 80 steps up a power supply voltage to a predetermined voltage, and the step-up operation is fully controlled by the AC power supply. The rectifier unit 90 includes a high-voltage current-limiting resistor RbO and a high-voltage rectifier circuit 91. A high AC voltage stepped up by the high- voltage transformer 80 is rectified by the rectifier circuit 91 to charge the energy storage capacitor 10, and the energy storage element 10 stores high-voltage electrical energy within a short period of time. A high-voltage feedback circuit 30 feeds back an energy storage charging voltage to the high-voltage threshold detection unit 40 for comparison. When a charging voltage reaches a target voltage, the high-voltage threshold detection unit 40 outputs a comparison signal to the timing control unit 50 to control the power supply switch 60 to be opened and thereby cut off a charging circuit. In addition, the timing control unit 50 closes the discharging switch 21 in the discharging unit 20, releasing a voltage on the energy storage element 10 through the discharging switch 21 to the piezoelectric ceramic plate 71, and the piezoelectric ceramic plate converts electrical energy into acoustic energy for output. Because the power supply switch 60 has already been opened in this case, after the discharging is completed, the pulse generation circuit 100 enters a standby state, thereby greatly reducing power consumption.

[0051] In the intermittent high-voltage pulse control method circuit provided in this embodiment, the pulse generation circuit 100 is triggered, before discharging, to start charging. After charging, discharging is performed after a period of delay (namely, delayed discharging control time Dt) to ensure that the energy storage element 10 has a sufficiently high stored voltage. The stored high-voltage energy is then rapidly (within 500 ns) released to the piezoelectric ceramic plate, and the piezoelectric ceramic plate converts electrical energy into mechanical energy to output an instantaneous sound pressure for acoustic pressure therapy.

[0052] In addition, internationally, the AC power supply voltage in different countries is usually divided into two types: 100-127 Vac / 60 Hz and 220-240 Vac / 50 Hz. To meet the needs of different voltage markets, in the circuit for the intermittent high-voltage pulse control method provided in this embodiment, the step-up transformer 80 has at least two input terminals with different turn ratios, and the pulse generation circuit 1 further includes a power supply switching unit 100 electrically connected to the input terminals of the step-up transformer 80. The power supply switching unit 100 includes a power supply voltage detection circuit 101 and a selectorswitch 102. The power supply voltage detection circuit 100 detects a voltage of the AC power supply and controls the selector switch 102 based on the detected voltage to select an input terminal with a corresponding turn ratio on the step-up transformer. The power supply switching unit 100 automatically switches an operating state based on the input power supply voltage. To be specific, the power supply voltage detection circuit 100 detects whether the input power supply voltage is 100-127 Vac / 60 Hz or 220-240 Vac / 50 Hz. Based on the monitored input power supply voltage, the selector switch 102 is controlled, through the selection of a transformer primary coil port, to change a transformer turn ratio for voltage step-up, thereby meeting charging requirements of a downstream energy storage element 10. Specifically, when the input power supply voltage is 127 Vac, to implement secondary voltage step-up to 8.3 kVac, the power supply switching unit 100 is switched to a first gear to select a transformer turn ratio of 1 : 65. When the input power supply voltage is 240 Vac, to implement secondary voltage step-up to 8.3 kVac, the power supply switching unit 100 is switched to a second gear to select a transformer turn ratio of 1:35, thereby implementing the same secondary high-voltage output and ensuring normal circuit operation.

[0053] Correspondingly, this embodiment provides an acoustic pressure therapy device including the above circuit for an intermittent high-voltage pulse control method.

[0054] In summary, in the intermittent high-voltage pulse control method and the circuit for an intermittent high-voltage pulse control method provided in the present invention, the timing control circuit issues the charging command at the beginning of each charging cycle, causing the pulse generation circuit to enter the charging state and, after charging is completed, to complete discharging, to output the pulse signal within the current charging cycle. Afterwards, the pulse generation circuit enters a standby state until the beginning of a next charging cycle, and then the pulse generation circuit is triggered again to enter the charging state. Compared with a continuous charging and replenishment approach, in the intermittent high-voltage pulse control method provided in this application, charging is performed in advance based on the operating frequency requirements of the piezoelectric ceramic plate before each pulse discharging, and a waiting state begins after the pulse discharging is completed. To be specific, within one charging cycle, the pulse generation circuit operates intermittently. This operating mode greatly reduces a frequency of charging and replenishment in the circuit, thereby significantly lowering power consumption and keeping the circuit in optimal condition.

[0055] The present invention has been disclosed in the preferred embodiments as described above, which is not intended to limit the present invention. Any person skilled in the art may make slight changes and modifications without departing from the spirit and scope of the presentinvention. Therefore, the scope of protection of the present invention shall be deemed to be the scope of protection in the claims.

Claims

Claims1. An intermittent high-voltage pulse control method, used to intermittently control a pulse generation circuit to output a pulse signal to a piezoelectric ceramic plate, and comprising: obtaining a charging cycle based on an operating frequency of the piezoelectric ceramic plate, wherein the charging cycle is longer than operating time Et of the pulse signal in the pulse generation circuit;issuing a charging command at the beginning of each charging cycle to trigger the pulse generation circuit to enter a charging state, and after charging is completed, performing discharging to release a stored energy voltage to the piezoelectric ceramic plate to complete output of the pulse signal within the current charging cycle; andafter outputting the pulse signal within the current charging cycle, issuing a sleep command to stop the operation of the pulse generation circuit until a next charging cycle begins, and then issuing the charging command again to trigger the pulse generation circuit to re-enter the charging state.

2. The intermittent high-voltage pulse control method according to claim 1, wherein the pulse generation circuit is connected to an alternating current (AC) power supply, an energy storage element is charged based on AC power, with charging time being less than an AC power supply cycle, and the intermittent high-voltage pulse control method further comprises:detecting an AC power supply zero-crossing signal; andtriggering, at a first AC power supply zero-crossing point after the charging command is issued, the pulse generation circuit to enter the charging state.

3. The intermittent high-voltage pulse control method according to claim 2, further comprising: starting timing upon issuance of the charging command within each charging cycle; monitoring a voltage across the energy storage element in the pulse generation circuit after the pulse generation circuit starts being charged;determining whether the voltage across the energy storage element has reached a preset target voltage;if yes, indicating that charging is completed, and completing timing to obtain charging command execution time St; andbased on the charging command execution time St and the operating time Et of the pulse signal, calculating delayed discharging control time Dt, after charging is completed, performing discharging after the delayed discharging control time Dt, and associating a discharging cycle with the charging cycle so that both have the same frequency, wherein the discharging control time is Dt = Et - St, and Et is the operating time of the pulse signal in the pulse generation circuit.

4. A circuit for an intermittent high-voltage pulse control method, comprising:a pulse generation circuit, comprising an energy storage element and a discharging unit, wherein the energy storage element is electrically connected to a charging power supply, the discharging unit forms a discharging loop between the energy storage element and a piezoelectric ceramic plate, and within each charging cycle, the energy storage element completes one charging and one discharging to output a pulse signal; anda timing control circuit, electrically connected to the pulse generation circuit, wherein the timing control circuit controls timing of the pulse generation circuit using the intermittent high-voltage pulse control method according to claim 1, to intermittently control an operating state of the pulse generation circuit within each charging cycle.

5. The circuit for an intermittent high-voltage pulse control method according to claim 4, wherein the timing control circuit comprises:a high-voltage feedback unit, electrically connected between two ends of the energy storage element in the pulse generation circuit to detect a voltage across the energy storage element in a charging state;a high-voltage threshold detection unit, comprising a comparator, wherein the comparator determines whether the voltage detected by the high-voltage feedback circuit across the energy storage element has reached a target voltage, and outputs a charging completion signal when the target voltage is reached; anda timing control unit, electrically connected to the high-voltage threshold detection circuit, wherein the timing control unit issues a charging command at the beginning of each charging cycle to trigger the pulse generation circuit to enter the charging state; upon receiving the charging completion signal fed back by the high-voltage threshold detection circuit, the timing control unit issues a stop command to the pulse generation circuit to stop charging; and subsequently, the timing control unit outputs a discharging signal to the discharging unit in the pulse generation circuit to connect a discharging loop, releasing the voltage across the energy storage element through the discharging loop to the piezoelectric ceramic plate, thereby implementing output of the pulse signal within the current cycle.

6. The circuit for an intermittent high-voltage pulse control method according to claim 5, wherein the charging power supply is an AC power supply, and the timing control circuit further comprises a zero-crossing detection circuit for detecting an AC power supply zero-crossing signal; and the timing control unit triggers, at a first AC power supply zero-crossing point after the charging command is issued, the pulse generation circuit to enter the charging state.

7. The circuit for an intermittent high-voltage pulse control method according to claim 6, wherein a timer is provided in the timing control unit, and the timing control unit triggers the timer to start timing simultaneously when issuing the charging command;the timing control unit turns off the timer upon receiving a charging completion signal to obtain charging command execution time St; andthe timing control unit calculates discharging control time Dt based on the timed charging command execution time and operating time of the pulse signal, outputs the discharging signal to the discharging unit after delayed discharging control time Dt, and associates a discharging cycle with the charging cycle so that both have the same frequency, wherein the discharging control time is Dt = Et - St, and Et is operating time of a pulse in the pulse generation circuit.

8. The circuit for an intermittent high-voltage pulse control method according to claim 5, wherein the timing control circuit comprises a power supply switch electrically connected between the pulse generation circuit and the charging power supply, the power supply switch is electrically connected to the timing control unit, and is closed or opened respectively when the timing control unit issues the charging command and the stop command.

9. The circuit for an intermittent high-voltage pulse control method according to claim 4, wherein the charging power supply is an AC power supply, the pulse generation circuit further comprises a step-up transformer and a rectifier unit, the step-up transformer is electrically connected to the AC power supply, steps up an AC voltage and outputs the AC voltage after step-up to the rectifier unit, and the rectifier unit outputs a direct current (DC) voltage to charge the energy storage element.

10. The circuit for an intermittent high-voltage pulse control method according to claim 9, wherein the step-up transformer has at least two input terminals with different turn ratios, and the pulse generation circuit further comprises a power supply switching unit electrically connected to the input terminals of the step-up transformer, the power supply switching unit comprises a power supply voltage detection circuit and a selector switch, the power supply voltage detection circuit detects a voltage of the AC power supply and controls the selector switch based on the detected voltage to select an input terminal with a corresponding turn ratio on the step-up transformer.

11. An acoustic pressure therapy device, comprising the circuit for an intermittent high-voltage pulse control method according to any one of claims 1 to 10.

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