Driving circuit with adjustable piezoelectric shock wave output intensity

Abstract

The utility model relates to a piezoelectric shock wave output intensity adjustable drive circuit, which comprises a main control unit, a PWM generation circuit, a voltage follower and a voltage doubling rectifying circuit, and is characterized in that the drive circuit comprises an LLC drive circuit, the control end of the LLC drive circuit is connected with the PWM generation circuit, the PWM generation circuit is electrically connected with the main control unit, the main control unit is connected with the control end of the voltage follower, and the voltage doubling rectifying circuit is electrically connected with the voltage follower. The output end of the voltage follower is connected with the input end of the LLC driving circuit, the output end of the LLC driving circuit is connected with the primary side of the high-frequency boosting transformer, the secondary side of the high-frequency boosting transformer is connected with the voltage doubling rectifying circuit, the output end of the voltage doubling rectifying circuit is connected with the energy storage capacitor, and the output end of the energy storage capacitor is connected with the high-voltage discharging circuit. The control end of the high-voltage discharge circuit is connected with the main control unit, and the output end of the high-voltage discharge circuit is connected with the piezoelectric crystal. According to the utility model, stable and high-speed driving of the piezo-electric crystal can be realized.

Description

Technical Field

[0001] The utility model belongs to the field of rehabilitation treatment medicine, and particularly relates to a driving circuit with adjustable output intensity of piezoelectric shock waves. Background Technique

[0002] Extracorporeal shock wave therapy is a non-invasive treatment method. Piezoelectric shock waves are formed by arranging hundreds of piezoelectric crystals on a concave surface. The piezoelectric crystals are driven by a high-voltage electric field, causing the volume of the piezoelectric crystals to change, thereby generating pressure waves. Then, an ellipsoid collects and guides all the energy to focus on the treatment site. Driving the piezoelectric crystals requires a rapid rise to a high voltage of several thousand volts. The higher the voltage, the shorter the rise time, and the faster the deformation of the piezoelectric crystals, thus generating shock waves.

[0003] The piezoelectric crystals are connected with a driving circuit. The existing driving circuit generates serious heat during high-power operation. Since the charging time of the capacitor is controlled to control the charging voltage of the capacitor, the output voltage is unstable, and the response speed of the high-voltage output is slow. The driving effect of the existing driving circuit is not good.

[0004] Therefore, there is an urgent need for a driving circuit with better performance to drive the piezoelectric crystals to work. Summary of the Invention

[0005] In order to solve the problem that the existing driving circuit has a poor driving effect on piezoelectric crystals, the utility model provides a driving circuit with adjustable output intensity of piezoelectric shock waves. The main control unit controls the LLC driving circuit through the PWM generating circuit to drive the high-frequency step-up transformer to solve the problem of component heating. At the same time, the output voltage of the high-voltage capacitor is stable, and the high-voltage discharge circuit has a fast response speed, realizing the stable and high-speed driving of the piezoelectric crystals.

[0006] To achieve the above object, the utility model proposes a driving circuit with adjustable output intensity of piezoelectric shock waves, including a driving circuit, a high-frequency step-up transformer, an energy storage capacitor, a high-voltage discharge circuit, and piezoelectric crystals. It also includes a main control unit, a PWM generating circuit, a voltage follower, and a voltage multiplier rectifier circuit. The driving circuit includes an LLC driving circuit. The control end of the LLC driving circuit is connected to the PWM generating circuit. The PWM generating circuit is electrically connected to the main control unit. The main control unit is connected to the control end of the voltage follower. The output end of the voltage follower is connected to the input end of the LLC driving circuit. The output end of the LLC driving circuit is connected to the primary side of the high-frequency step-up transformer. The secondary side of the high-frequency step-up transformer is connected to the voltage multiplier rectifier circuit. The output end of the voltage multiplier rectifier circuit is connected to the energy storage capacitor. The output end of the energy storage capacitor is connected to the high-voltage discharge circuit. The control end of the high-voltage discharge circuit is connected to the main control unit. The output end of the high-voltage discharge circuit is connected to the piezoelectric crystals.

[0007] Further, a first switching power supply is connected to the input end of the voltage follower, and a second switching power supply is connected to the main control unit and the PWM generation circuit. Both the first switching power supply and the second switching power supply include a rectifier and a power supply chip. One end of the rectifier is connected to the 220V mains power, and the other end is connected to the power supply chip.

[0008] Set the first switching power supply to output a high-voltage and high-power current for piezoelectric crystal drive. The second switching power supply supplies power to the main control unit and the PWM generation circuit.

[0009] Further, the PWM generation circuit includes a 555 timer, and the trigger terminal and the threshold terminal of the 555 timer are electrically connected to the main control unit respectively.

[0010] The PWM generation circuit uses a 555 timer to generate a PWM signal with the required frequency.

[0011] Further, the LLC drive circuit includes MOS1 and MOS2, and the G bases of MOS1 and MOS2 are respectively connected to the output terminal of the 555 timer.

[0012] The LLC drive circuit converts direct current into alternating current to drive the high-frequency step-up transformer. The high-frequency step-up transformer raises the voltage adjusted by the first switching power supply to a predetermined voltage in proportion.

[0013] Further, an RC charging circuit is connected to the voltage doubling rectifier circuit, and the other end of the RC charging circuit is connected to the energy storage capacitor.

[0014] The voltage doubling rectifier circuit rectifies the output current of the high-frequency step-up transformer into a DC voltage and boosts the voltage by N times. The RC charging circuit is set to charge the energy storage capacitor.

[0015] Further, the high-voltage discharge circuit includes a toroidal transformer, and the toroidal transformer is connected with a plurality of MOS transistors and a trigger MOS transistor. The G and S poles of the plurality of MOS transistors are connected to the toroidal transformer, and the D pole of one of the MOS transistors is connected to the piezoelectric crystal;

[0016] The G pole of the trigger MOS transistor is connected to the main control unit, and the D pole of the trigger MOS transistor is connected to the toroidal transformer to form a loop.

[0017] When the energy storage capacitor discharges, the main control unit controls the trigger MOS transistor to conduct, and the high-voltage discharge circuit outputs electrical energy to act on the piezoelectric crystal.

[0018] Further, an optocoupler element is provided between the main control unit and the voltage follower and the voltage doubling rectifier circuit, and the main control unit is connected to the voltage follower and the voltage doubling rectifier circuit through the optocoupler element.

[0019] The circuits are isolated by optocoupler components to ensure the safety of each circuit.

[0020] By the above technical solution, the beneficial effects of the present utility model are as follows:

[0021] The present utility model realizes the stable and high-speed driving of piezoelectric crystals. The 220V mains power is converted into a DC power supply by the first switching power supply. The main control unit adjusts the PWM duty cycle to control the supply voltage through a voltage follower. The PWM generating circuit drives the LLC driving circuit to output a high-frequency sine wave to drive the high-frequency step-up transformer. The high-frequency step-up transformer outputs an AC high-voltage current, which is rectified by a voltage multiplier rectification circuit into a DC high voltage. The RC charging circuit stabilizes the charging current and voltage rise, charges the energy storage capacitor to a predetermined voltage, and the main control unit controls the high-voltage discharge circuit to supply the electrical energy in the capacitor to the piezoelectric crystal in the form of pulses at a certain frequency. The piezoelectric crystal deforms through a rapidly rising high-voltage pulse, thereby generating a shock wave. Description of the Drawings

[0022] Figure 1 It is a schematic circuit diagram of a driving circuit with adjustable output intensity of piezoelectric shock waves according to the present utility model;

[0023] Figure 2 It is a PWM generating circuit of a driving circuit with adjustable output intensity of piezoelectric shock waves according to the present utility model;

[0024] Figure 3 It is an LLC driving circuit of a driving circuit with adjustable output intensity of piezoelectric shock waves according to the present utility model;

[0025] Figure 4 It is a voltage multiplier rectification circuit of a driving circuit with adjustable output intensity of piezoelectric shock waves according to the present utility model;

[0026] Figure 5 It is a high-voltage discharge circuit of a driving circuit with adjustable output intensity of piezoelectric shock waves according to the present utility model.

[0027] Reference numerals in the drawings: 1 is the main control unit, 2 is the PWM generating circuit, 3 is the voltage follower, 4 is the voltage multiplier rectification circuit, 5 is the LLC driving circuit, 6 is the high-frequency step-up transformer, 7 is the energy storage capacitor, 8 is the high-voltage discharge circuit, 9 is the piezoelectric crystal, 10 is the first switching power supply, 11 is the second switching power supply, 12 is the trigger MOS tube. Detailed Embodiments

[0028] The present utility model will be further described below in conjunction with the drawings and specific embodiments:

[0029] Embodiment 1

[0030] As Figures 1 to 5As shown in the figure, a drive circuit with adjustable output intensity of piezoelectric shock waves includes a drive circuit, a high-frequency step-up transformer 6, an energy storage capacitor 7, a high-voltage discharge circuit 8, and a piezoelectric crystal 9. It also includes a main control unit 1, a PWM generation circuit 2, a voltage follower 3, and a voltage multiplier rectification circuit 4. The drive circuit includes an LLC drive circuit 5. The control end of the LLC drive circuit 5 is connected to the PWM generation circuit 2. The PWM generation circuit 2 is electrically connected to the main control unit 1. The main control unit 1 is connected to the control end of the voltage follower 3. The output end of the voltage follower 3 is connected to the input end of the LLC drive circuit 5. The output end of the LLC drive circuit 5 is connected to the primary side of the high-frequency step-up transformer 6. The secondary side of the high-frequency step-up transformer 6 is connected to the voltage multiplier rectification circuit 4. The output end of the voltage multiplier rectification circuit 4 is connected to the energy storage capacitor 7. The output end of the energy storage capacitor 7 is connected to the high-voltage discharge circuit 8. The control end of the high-voltage discharge circuit 8 is connected to the main control unit 1. The output end of the high-voltage discharge circuit 8 is connected to the piezoelectric crystal 9.

[0031] In this embodiment, the main control unit 1 is an MCU chip. The MCU chip includes an STM32 single-chip microcomputer.

[0032] A first switching power supply 10 is connected to the input end of the voltage follower 3. A second switching power supply 11 is connected to the main control unit 1 and the PWM generation circuit 2. Both the first switching power supply 10 and the second switching power supply 11 include a rectifier and a power supply chip. One end of the rectifier is connected to the 220V mains power, and the other end is connected to the power supply chip.

[0033] The first switching power supply 10 outputs DC100V direct current, and the second switching power supply 11 outputs DC5V and DC3.3V current.

[0034] The PWM generation circuit 2 includes a 555 timer. The trigger terminal (TR pin) and the threshold terminal (THR pin) of the 555 timer are respectively electrically connected to the main control unit 1.

[0035] The LLC drive circuit 5 includes MOS1 and MOS2. The G bases of MOS1 and MOS2 are respectively connected to the output end of the 555 timer.

[0036] Body diodes are provided on MOS1 and MOS2.

[0037] The voltage multiplier rectification circuit 4 is connected to an RC charging circuit, and the other end of the RC charging circuit is connected to the energy storage capacitor 7.

[0038] The high-voltage discharge circuit 8 includes a toroidal transformer. The toroidal transformer is connected to a plurality of MOS transistors and a trigger MOS transistor 12. The G and S poles of the plurality of MOS transistors are connected to the toroidal transformer. The D pole of one MOS transistor is connected to the piezoelectric crystal 9;

[0039] The G pole of the trigger MOS transistor 12 is connected to the main control unit 1, and the D pole of the trigger MOS transistor 12 is connected to the toroidal transformer to form a loop.

[0040] Body diodes are provided on the MOS transistor and the trigger MOS transistor 12.

[0041] An opto-coupler element is provided between the main control unit 1 and the voltage follower 3 and the voltage multiplier rectifier circuit 4, and the main control unit 1 is connected to the voltage follower 3 and the voltage multiplier rectifier circuit 4 through the opto-coupler element.

[0042] During operation, the 220V mains power is converted into a DC power supply by the first switching power supply 10. The main control unit 1 adjusts the PWM duty cycle to control the supply voltage through the voltage follower 3. The PWM generation circuit 2 drives the LLC drive circuit 5 to output a high-frequency sine wave to drive the high-frequency step-up transformer 6, and the high-frequency step-up transformer 6 outputs an AC high-voltage current. The AC high-voltage current is rectified by the voltage multiplier rectifier circuit 4 to become a DC high voltage. As Figure 4 shown, the voltage multiplier rectifier circuit 4 is a 2x voltage multiplier rectifier circuit. The output terminal of the voltage multiplier rectifier circuit 4 is connected to the RC charging circuit, and the RC charging circuit charges the energy storage capacitor 7 to a predetermined voltage. The main control unit 1 controls the on / off of the trigger MOS transistor 12, and the main control unit 1 controls the on / off frequency of the trigger MOS transistor 12. The high-voltage discharge circuit 8 supplies the electrical energy in the energy storage capacitor 7 to the piezoelectric crystal 9 in the form of on / off frequency pulses, and the piezoelectric crystal 9 deforms through a rapidly rising high-voltage pulse, thereby generating a shock wave.

[0043] The above-described embodiments are only the preferred embodiments of the present invention, and do not limit the scope of implementation of the present invention. Therefore, any equivalent changes or modifications made according to the structure, features, and principles described in the scope of the present invention patent should be included in the scope of the present invention's patent application.

Claims

1. A driving circuit with adjustable output intensity of piezoelectric shock waves, comprising a driving circuit, a high-frequency step-up transformer (6), an energy storage capacitor (7), a high-voltage discharge circuit (8) and a piezoelectric crystal (9), characterized in that, It also includes a main control unit (1), a PWM generation circuit (2), a voltage follower (3), and a voltage multiplier rectification circuit (4). The drive circuit includes an LLC drive circuit (5). The control end of the LLC drive circuit (5) is connected to the PWM generation circuit (2). The PWM generation circuit (2) is electrically connected to the main control unit (1). The main control unit (1) is connected to the control end of the voltage follower (3). The output end of the voltage follower (3) is connected to the input end of the LLC drive circuit (5). The output end of the LLC drive circuit (5) is connected to the primary side of the high-frequency step-up transformer (6). The secondary side of the high-frequency step-up transformer (6) is connected to the voltage multiplier rectification circuit (4). The output end of the voltage multiplier rectification circuit (4) is connected to the energy storage capacitor (7). The output end of the energy storage capacitor (7) is connected to the high-voltage discharge circuit (8). The control end of the high-voltage discharge circuit (8) is connected to the main control unit (1). The output end of the high-voltage discharge circuit (8) is connected to the piezoelectric crystal (9).

2. The drive circuit with adjustable output intensity of piezoelectric shock wave according to claim 1, characterized in that, The input end of the voltage follower (3) is connected to a first switching power supply (10). The main control unit (1) and the PWM generation circuit (2) are connected to a second switching power supply (11). Both the first switching power supply (10) and the second switching power supply (11) include a rectifier and a power supply chip. One end of the rectifier is connected to the 220V mains electricity, and the other end is connected to the power supply chip.

3. The drive circuit with adjustable output intensity of piezoelectric shock wave according to claim 1, characterized in that, The PWM generation circuit (2) includes a 555 timer. The trigger terminal and the threshold terminal of the 555 timer are respectively and electrically connected to the main control unit (1).

4. A driving circuit with adjustable output intensity of piezoelectric shock waves according to claim 3, characterized in that, The LLC drive circuit (5) includes MOS1 and MOS2. The G bases of MOS1 and MOS2 are respectively connected to the output end of the 555 timer.

5. A driving circuit with adjustable output intensity of piezoelectric shock waves according to claim 1, characterized in that, The voltage multiplier rectification circuit (4) is connected to an RC charging circuit. The other end of the RC charging circuit is connected to the energy storage capacitor (7).

6. The drive circuit with adjustable output intensity of piezoelectric shock wave according to claim 1, characterized in that The high-voltage discharge circuit (8) includes a toroidal transformer. The toroidal transformer is connected to a plurality of MOS transistors and a trigger MOS transistor (12). The G poles and S poles of the plurality of MOS transistors are connected to the toroidal transformer. The D pole of one of the MOS transistors is connected to the piezoelectric crystal (9). The G pole of the trigger MOS transistor (12) is connected to the main control unit (1). The D pole of the trigger MOS transistor (12) is connected to the toroidal transformer to form a loop.

7. A driving circuit with adjustable output intensity of piezoelectric shock waves according to claim 1, characterized in that, An opto-coupler element is provided between the main control unit (1) and the voltage follower (3) and the voltage multiplier rectification circuit (4). The main control unit (1) is connected to the voltage follower (3) and the voltage multiplier rectification circuit (4) through the opto-coupler element.

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