Transmitting circuit of ultrasonic transducer and ultrasonic transducer

Abstract

The utility model relates to the technical field of ultrasonic transducers, and discloses a transmitting circuit of an ultrasonic transducer, the ultrasonic transducer and the transmitting circuit, the transmitting circuit comprises a waveform generation module, a transformer module and an output shielding module, the output end of the waveform generation module is connected with the primary side of the transformer module, and the waveform generation module is used for generating and outputting excitation; the secondary side of the transformer module is connected with the ultrasonic transducer through the output shielding module, and the transformer module is used for outputting a transmitted waveform to the ultrasonic transducer; the output shielding module is used for inhibiting the echo signal from being output to the transformer module based on the internal conduction voltage drop, and the voltage signal generated after the ultrasonic transducer receives the echo is lower than the conduction voltage drop, so that the voltage signal generated after the echo is received is shielded and prevented from entering the transformer module and the waveform generation module, and the output voltage of the ultrasonic transducer is reduced. And secondary interference signals are avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of ultrasonic transducer, concretely relates to the transmitting circuit of ultrasonic transducer, ultrasonic transducer. BACKGROUND

[0002] The ultrasonic transducer is the core component of the ultrasonic liquid level meter, and the main functional component is piezoelectric ceramic, which realizes the mutual conversion of mechanical energy and electrical energy by using piezoelectric effect.

[0003] Generally, the existing measurement system defaults to use single-pulse measurement for short distance and multi-pulse measurement for long distance, and the pulse signals of the two modes are emitted alternately. However, this method has a defect, that is, when the emission surface is not ideal, the emission signal of the single-pulse excitation signal is relatively weak, and no normal signal is detected at a short distance. At the same time, when multi-pulse excitation is used, the real signal at a short distance is covered due to the influence of resonance and other factors, resulting in the detection of secondary echo signals. When the detection of a short distance, a sudden change in distance, or no echo is received, the excitation signal calibration is triggered, the single-chip microcomputer actively disconnects the excitation power supply, and the electricity of the energy storage capacitor is discharged. Then, the pulse level control is used to charge the time, and the number of pulses is gradually increased until the distance is measured. If the distance is not consistent with the last test distance, the wave emission configuration of this time is saved. SUMMARY

[0004] Therefore, the utility model provides the transmitting circuit of ultrasonic transducer, ultrasonic transducer to solve how to reduce the influence of secondary echo signals on the circuit.

[0005] In a first aspect, the utility model provides a kind of transmitting circuit of ultrasonic transducer, comprising: waveform generation module, transformer module and output shielding module, wherein the output end of waveform generation module is connected with the primary side of transformer module, and waveform generation module is used to generate and output excitation;The secondary side of transformer module is connected with ultrasonic transducer by output shielding module, and transformer module is used to output transmission waveform to ultrasonic transducer;Output shielding module is used to suppress echo signal output to transformer module based on its internal conduction voltage drop.

[0006] The utility model output shielding module is used to suppress echo signal output to transformer module based on its internal conduction voltage drop, since the voltage signal lower than conduction voltage drop is generated after ultrasonic transducer receives echo, so as to shield the voltage signal generated after receiving echo, avoid its entering transformer module and waveform generation module, avoid generating secondary interference signal.

[0007] In an alternative embodiment, the waveform generating module comprises: a power storage unit, a forward excitation unit and a reverse excitation unit, wherein the first end of the power storage unit is connected to a charging voltage, the second end of the power storage unit is connected to a charge-discharge control signal, and the third end of the power storage unit is connected to the second end of the primary side of the transformer module; the charging voltage is a rectangular wave; the first end of the forward excitation unit is connected to a first control signal, and the second end of the forward excitation unit is connected to the first end of the primary side of the transformer module; the first end of the reverse excitation unit is connected to a second control signal, and the second end of the reverse excitation unit is connected to the third end of the primary side of the transformer module.

[0008] In an alternative embodiment, the power storage unit comprises: a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a polarity capacitor, a first inductor, a first transistor and a second transistor, wherein the control end of the first transistor is connected to the charge-discharge control signal through the first resistor, the control end of the first transistor is also connected to the first end of the second resistor, the first end of the first transistor is connected to the first end of the third resistor, the second end of the first transistor is connected to the second end of the second resistor and then grounded, the control end of the second transistor is connected to the first end of the third resistor and the first end of the fourth resistor, the first end of the second transistor is connected to the charging voltage and also connected to the second end of the fourth resistor, the second end of the second transistor is connected to the first end of the first inductor and the first end of the polarity capacitor through the fifth resistor; the second end of the polarity capacitor is grounded; and the second end of the first inductor is connected to the second end of the primary side of the transformer module.

[0009] In an alternative embodiment, the forward excitation unit comprises: a sixth resistor, a seventh resistor and a third transistor, wherein the control end of the third transistor is connected to the first control signal through the sixth resistor, the control end of the third transistor is also connected to the first end of the seventh resistor, the first end of the third transistor is connected to the first end of the primary side of the transformer module, and the second end of the third transistor is connected to the second end of the seventh resistor and then grounded.

[0010] In an alternative embodiment, the reverse excitation unit comprises: an eighth resistor, a ninth resistor and a fourth transistor, wherein the control end of the fourth transistor is connected to the first control signal through the eighth resistor, the control end of the fourth transistor is also connected to the first end of the ninth resistor, the first end of the fourth transistor is connected to the third end of the primary side of the transformer module, and the second end of the fourth transistor is connected to the second end of the ninth resistor and then grounded.

[0011] In an alternative embodiment, the output shielding module comprises: a first output shielding unit and a second output shielding unit, wherein a first end of the first output shielding unit is connected with a first end of the secondary side of the transformer module, and a second end of the first output shielding unit is connected with the ultrasonic transducer; a first end of the second output shielding unit is connected with a second end of the secondary side of the transformer module, and a second end of the second output shielding unit is connected with the ultrasonic transducer.

[0012] In an alternative embodiment, the first output shielding unit comprises: a first diode and a second diode, wherein a cathode of the first diode is connected with an anode of the second diode and a first end of the secondary side of the transformer module, and an anode of the first diode is connected with a cathode of the second diode and the ultrasonic transducer.

[0013] In an alternative embodiment, the second output shielding unit comprises: a third diode and a fourth diode, wherein a cathode of the third diode is connected with an anode of the fourth diode and a second end of the secondary side of the transformer module, and an anode of the third diode is connected with a cathode of the fourth diode and the ultrasonic transducer.

[0014] In an alternative embodiment, the transmitting circuit of the ultrasonic transducer further comprises: a resistance matching circuit, wherein a first end and a second end of the resistance matching circuit are connected with the second end of the first output shielding unit and the second end of the second output shielding unit, respectively.

[0015] In a second aspect, the utility model provides a kind of ultrasonic transducer, comprising: the transmitting circuit of the ultrasonic transducer of the first aspect and any alternative embodiment and ultrasonic transducer body. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the specific embodiments of the utility model or the technical solutions in the prior art, the drawings needed in the specific embodiments or prior art description will be briefly introduced as follows, and obviously, the drawings in the following description are some embodiments of the utility model, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0017] Figure 1 It is the composition diagram of the transmitting circuit of the ultrasonic transducer according to the embodiment of the utility model;

[0018] Figure 2 It is the composition diagram of the transmitting circuit of another ultrasonic transducer according to the embodiment of the utility model;

[0019] Figure 3 It is the specific circuit structure diagram of the transmitting circuit of the ultrasonic transducer according to the embodiment of the utility model;

[0020] Figure 4This is a schematic diagram of the transmitting circuit of another ultrasonic transducer according to an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0022] This embodiment provides a transmitting circuit for an ultrasonic transducer, such as... Figure 1 As shown, it includes: waveform generation module 1, transformer module 2 and output shielding module 3.

[0023] like Figure 1 As shown, the output terminal of waveform generation module 1 is connected to the primary side of transformer module 2. Waveform generation module 1 is used to generate and output excitation. Specifically, waveform generation module 1 has a built-in energy storage device. Before transformer module 2 outputs the transmitted waveform, the energy storage device is charged. After that, the energy storage device is controlled to discharge to transformer module 2, and transformer module 2 outputs the transmitted waveform.

[0024] like Figure 1 As shown, the secondary side of transformer module 2 is connected to the ultrasonic transducer via output shielding module 3. Transformer module 2 is used to output the transmitted waveform to the ultrasonic transducer. Specifically, the primary coil of transformer module 2 is connected to waveform generation module 1, and the secondary coil of transformer module 2 is connected to output shielding module 3.

[0025] like Figure 1 As shown, the output shielding module 3 is used to suppress the echo signal output to the transformer module 2 based on its internal on-state voltage drop. Specifically, when the transformer module 2 outputs the transmitted waveform, it may receive an echo signal. However, on the echo signal transmission line, because the output shielding module 3 has built-in components with unidirectional conduction and on-state voltage drop, the echo signal is in the millivolt range, far lower than the on-state voltage drop. Therefore, it can prevent the echo signal from entering the transformer module 2 and generating secondary interference signals. That is, it reduces the dead zone by actively reducing the voltage of the excitation signal and suppresses the resonance between the transducer and the fixed mounting position.

[0026] In some alternative implementations, such as Figure 2 As shown, the waveform generation module 1 includes: an energy storage unit 11, a forward excitation unit 12, and a reverse excitation unit 13.

[0027] like Figure 2As shown, the first end of the power storage unit 11 is connected to a charging voltage VIN, the second end of the power storage unit 11 is connected to a charge-discharge control signal VCON, and the third end of the power storage unit 11 is connected to the second end of the primary side of the transformer module 2. The charging voltage VIN is a rectangular wave.

[0028] Specifically, the power storage unit 11 is a storage device. Before the transformer module 2 outputs the transmission waveform, the charge-discharge control signal VCON controls the charging voltage VIN to charge the storage device. After that, the charge-discharge control signal VCON controls the storage device to discharge to the transformer module 2, and the transformer module 2 outputs the transmission waveform.

[0029] As shown, Figure 2 the first end of the forward excitation unit 12 is connected to a first control signal CON_N, and the second end of the forward excitation unit 12 is connected to the first end of the primary side of the transformer module 2.

[0030] As shown, Figure 2 the first end of the reverse excitation unit 13 is connected to a second control signal CON_P, and the second end of the reverse excitation unit 13 is connected to the third end of the primary side of the transformer module 2.

[0031] Specifically, when the first control signal CON_N controls the forward excitation unit 12 to be turned on and the second control signal CON_P controls the reverse excitation unit 13 to be turned off, a forward excitation is injected into the primary side of the transformer module 2; when the first control signal CON_N controls the forward excitation unit 12 to be turned off and the second control signal CON_P controls the reverse excitation unit 13 to be turned on, a reverse excitation is injected into the primary side of the transformer module 2.

[0032] Alternatively, the forward excitation unit 12 and the reverse excitation unit 13 each include a controllable switch. The controllable switch is controlled by the first control signal CON_N or the second control signal CON_P. The turn-on or turn-off of the controllable switch forms different excitation circuits to inject a forward excitation or a reverse excitation into the transformer module 2.

[0033] In some optional embodiments, as shown, Figure 3 the power storage unit 11 includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a polarity capacitor C1, a first inductor L1, a first transistor Q1, and a second transistor Q2, Figure 3 the transformer module 2 includes a transformer T.

[0034] As shown, Figure 3As shown, the control terminal of the first transistor Q1 is connected to the charge-discharge control signal VCON through the first resistor R1, and is also connected to the first terminal of the second resistor R2. The first terminal of the first transistor Q1 is connected to the first terminal of the third resistor R3, and the second terminal of the first transistor Q1 is connected to the second terminal of the second resistor R2 and then grounded. The control terminal of the second transistor Q2 is connected to the first terminal of the third resistor R3 and the first terminal of the fourth resistor R4. The first terminal of the second transistor Q2 is connected to the charging voltage VIN, and is also connected to the second terminal of the fourth resistor R4. The second terminal of the second transistor Q2 is connected to the first terminal of the first inductor L1 and the first terminal of the polarity capacitor C1 through the fifth resistor R5. The second terminal of the polarity capacitor C1 is grounded. The second terminal of the first inductor L1 is connected to the second terminal of the primary side of the transformer module 2.

[0035] Specifically, the power storage unit 11 is actually composed of two switching circuits. The first switching circuit mainly includes the first transistor Q1, and the second switching circuit mainly includes the second transistor Q2. The on-off of the first transistor Q1 is controlled by the charge-discharge control signal VCON, and the on-off of the second transistor Q2 is controlled by the on-off of the first transistor Q1. For example, when it is necessary to charge the polarity capacitor C1, the charge-discharge control signal VCON is a charging signal, then the first transistor Q1 is turned on, the second transistor Q2 is turned on, and the charging voltage VIN charges the polarity capacitor C1. When it is necessary to discharge the polarity capacitor C1, the charge-discharge control signal VCON is a discharging signal, then the first transistor Q1 is turned off, the second transistor Q2 is turned off, and the polarity capacitor C1 is discharged.

[0036] For example, in the first embodiment, Figure 3 Figure 3 the first transistor Q1 is an IGBT tube, and the second transistor Q2 is an MOS tube. The source of the Q2 is connected to the charging terminal VIN, the charging terminal VIN outputs a rectangular wave and charges the polarity capacitor C1 through the Q2. The Q1 is connected to the control terminal VCON. When the control terminal outputs a high level, the collector and emitter of the Q1 are turned on, thereby turning on the Q2, so that the charging voltage VIN charges the polarity capacitor C1. After the control terminal outputs several high levels, the VIN is switched to output a low level, and the CON_P or CON_N outputs a high level, so as to discharge the polarity capacitor C1.

[0037] In some optional embodiments, for example, Figure 3 ​As shown, the forward excitation unit 12 includes a sixth resistor R6, a seventh resistor R7, and a third transistor Q3. The control terminal of the third transistor Q3 is connected to the first control signal CON_N through the sixth resistor R6. The control terminal of the third transistor Q3 is also connected to the first terminal of the seventh resistor R7. The first terminal of the third transistor Q3 is connected to the first terminal of the primary side of the transformer module 2. The second terminal of the third transistor Q3 is connected to the second terminal of the seventh resistor R7 and then grounded.

[0038] Specifically, when the third transistor Q3 is turned on, it forms a forward excitation circuit, and the polarized capacitor C1 discharges to the transformer module 2 through the forward excitation circuit.

[0039] For example, with Figure 3 Taking the third transistor Q3 as an example, the drain of Q3 is connected to the third terminal of the transformer T, and a resistor R7 is connected between the gate and the source of Q3. The gate of the first MOSFET Q1 is also connected to R6, and the other end of R6 is also connected to the first control signal CON_N.

[0040] In some alternative implementations, such as Figure 3 As shown, the reverse excitation unit 13 includes an eighth resistor R8, a ninth resistor R9, and a fourth transistor Q4. The control terminal of the fourth transistor Q4 is connected to the first control signal CON_N through the eighth resistor R8. The control terminal of the fourth transistor Q4 is also connected to the first terminal of the ninth resistor R9. The first terminal of the fourth transistor Q4 is connected to the third terminal of the primary side of the transformer module 2. The second terminal of the fourth transistor Q4 is connected to the second terminal of the ninth resistor R9 and then grounded.

[0041] Specifically, when the fourth transistor Q4 is turned on, it forms a reverse excitation circuit, and the polarized capacitor C1 discharges to the transformer module 2 through the reverse excitation circuit.

[0042] For example, with Figure 3 For example, the fourth transistor Q4 is a MOSFET. The drain of Q4 is connected to the first terminal of the transformer. A resistor R9 is connected between the gate and the source of Q4. The gate of Q4 is also connected to a resistor R8. The other end of R8 is also connected to the second control signal CON_P.

[0043] Specifically, refer to Figure 4, the control signal source alternately outputs a high level signal (i.e. the first control signal CON_N or the second control signal CON_P) to the first MOS tube Q1 and the second MOS tube Q2, so that the first end or the third end of the transformer is conducted to the ground, thereby enabling the positive electrode of the polarity capacitor C1 to discharge to the ground. In the process of discharging, the current flows through the primary side coil of the transformer, thereby enabling the secondary side coil of the transformer to discharge to the ultrasonic transducer, thereby realizing the function of outputting ultrasonic waves. When CON_N outputs a high level, the third end of the primary side coil of the transformer is conducted to the ground, the output end OUT1 outputs a high level, and OUT2 outputs a low level. When CON_P outputs a high level, the first end of the secondary side coil of the transformer is conducted to the ground, the output end OUT1 outputs a low level, and OUT2 outputs a high level.

[0044] Specifically, the amount of charge in the polarity capacitor C1 (i.e. the potential difference between the two ends of the polarity capacitor C1) is controlled by controlling the time (or the number of pulses) of charging the polarity capacitor C1, thereby controlling the output ends OUT1 and OUT2 to output higher voltage in a shorter time, realizing the excitation of the ultrasonic transducer and the high-frequency vibration of the ultrasonic transducer under the action of the piezoelectric effect to generate ultrasonic waves.

[0045] In some optional embodiments, as shown in Figure 4 The output shielding module 3 includes a first output shielding unit 31 and a second output shielding unit 32.

[0046] As shown in Figure 3 The first end of the first output shielding unit 31 is connected with the first end of the secondary side of the transformer module 2, and the second end of the first output shielding unit 31 is connected with the ultrasonic transducer. The first end of the second output shielding unit 32 is connected with the second end of the secondary side of the transformer module 2, and the second end of the second output shielding unit 32 is connected with the ultrasonic transducer.

[0047] Specifically, the transformer module 2 mainly includes a transformer, and the secondary side of the transformer has two output ends. An output shielding unit is arranged on each line, and the output shielding units are all arranged with unidirectional conduction and conduction voltage drop components.

[0048] In some optional embodiments, as shown in Figure 3 The first output shielding unit 31 includes a first diode D1 and a second diode D2. The cathode of the first diode D1 is connected with the anode of the second diode D2 and the first end of the secondary side of the transformer module 2, and the anode of the first diode D1 is connected with the cathode of the second diode D2 and the ultrasonic transducer.

[0049] In some optional embodiments, as shown in Figure 3As shown, the second output shielding unit 32 comprises a third diode D3 and a fourth diode D4, wherein the cathode of the third diode D3 is connected with the anode of the fourth diode D4 and the second end of the secondary side of the transformer module 2, and the anode of the third diode D3 is connected with the cathode of the fourth diode D4 and the ultrasonic transducer.

[0050] Specifically, as shown in the figure, four diodes D1-D4 are included, wherein the diodes D1 and D2 are connected in series between the output end OUT1 and one end of the secondary side coil of the transformer, and the diodes D3 and D4 are connected in series in the same way. Figure 3 When the ultrasonic transducer generates a back echo signal under the action of an ultrasonic echo, the back echo signal enters the output shielding module 3 through the output ends OUT1 and OUT2.

[0051] In some optional embodiments, the transmitting circuit of the ultrasonic transducer further comprises a resistance matching circuit, wherein the first end and the second end of the resistance matching circuit are respectively connected with the second end of the first output shielding unit 31 and the second end of the second output shielding unit 32. ​ As shown in the figure, the resistance matching circuit comprises a tenth resistor R10 to realize impedance matching of the ultrasonic transducer.

[0052] In the embodiment, an ultrasonic transducer is provided, which comprises the transmitting circuit of the ultrasonic transducer and the ultrasonic transducer body in the above embodiment and any optional embodiment thereof.

[0053] Although the embodiments of the present application are described in conjunction with the drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope defined by the appended claims.

Claims

1. A transmit circuit for an ultrasonic transducer, characterized by, The application relates to an ultrasonic transducer module, comprising: a waveform generating module, a transformer module and an output shielding module, wherein, an output end of the waveform generating module is connected with a primary side of the transformer module, the waveform generating module is used for generating and outputting excitation; a secondary side of the transformer module is connected with an ultrasonic transducer through the output shielding module, the transformer module is used for outputting a transmitting waveform to the ultrasonic transducer; the output shielding module is used for inhibiting echo signal output to the transformer module based on internal conduction voltage drop.

2. The transmit circuit for an ultrasonic transducer of claim 1, wherein, The waveform generating module comprises: a power storage unit, a forward excitation unit and a reverse excitation unit, wherein, a first end of the power storage unit is connected with a charging voltage, a second end of the power storage unit is connected with a charging and discharging control signal, a third end of the power storage unit is connected with a second end of the primary side of the transformer module; the charging voltage is a rectangular wave; a first end of the forward excitation unit is connected with a first control signal, a second end of the forward excitation unit is connected with a first end of the primary side of the transformer module; 3. The transmit circuit for an ultrasonic transducer of claim 2, wherein, a first end of the reverse excitation unit is connected with a second control signal, a second end of the reverse excitation unit is connected with a third end of the primary side of the transformer module. The power storage unit comprises: a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a polarity capacitor, a first inductor, a first transistor and a second transistor, wherein, a control end of the first transistor is connected with the charging and discharging control signal through the first resistor, the control end of the first transistor is also connected with a first end of the second resistor, a first end of the first transistor is connected with a first end of the third resistor, a second end of the first transistor is connected with a second end of the second resistor and then grounded; a control end of the second transistor is connected with a first end of the third resistor and a first end of the fourth resistor, a first end of the second transistor is connected with the charging voltage, the first end of the second transistor is also connected with a second end of the fourth resistor, a second end of the second transistor is connected with a first end of the first inductor and a first end of the polarity capacitor through the fifth resistor; 4. The transmit circuit for an ultrasonic transducer of claim 2, wherein, a second end of the polarity capacitor is grounded; a second end of the first inductor is connected with the second end of the primary side of the transformer module.

5. The transmit circuit for an ultrasonic transducer of claim 2, wherein, The forward excitation unit comprises: a sixth resistor, a seventh resistor and a third transistor, wherein, a control end of the third transistor is connected with the first control signal through the sixth resistor, the control end of the third transistor is also connected with a first end of the seventh resistor, a first end of the third transistor is connected with the first end of the primary side of the transformer module, and a second end of the third transistor is connected with a second end of the seventh resistor and then grounded. The reverse excitation unit comprises: an eighth resistor, a ninth resistor and a fourth transistor, wherein, a control end of the fourth transistor is connected with the first control signal through the eighth resistor, the control end of the fourth transistor is also connected with a first end of the ninth resistor, a first end of the fourth transistor is connected with the third end of the primary side of the transformer module, and a second end of the fourth transistor is connected with a second end of the ninth resistor and then grounded.

6. The transmit circuit for an ultrasonic transducer of claim 1, wherein, The output shielding module comprises a first output shielding unit and a second output shielding unit, wherein, a first end of the first output shielding unit is connected with a first end of the secondary side of the transformer module, and a second end of the first output shielding unit is connected with the ultrasonic transducer; a first end of the second output shielding unit is connected with a second end of the secondary side of the transformer module, and a second end of the second output shielding unit is connected with the ultrasonic transducer.

7. The transmit circuit for an ultrasonic transducer of claim 6, wherein, The first output shielding unit comprises a first diode and a second diode, wherein, a cathode of the first diode is connected with an anode of the second diode and a first end of the secondary side of the transformer module, and an anode of the first diode is connected with a cathode of the second diode and the ultrasonic transducer.

8. The transmit circuit for an ultrasonic transducer of claim 6, wherein, The second output shielding unit comprises a third diode and a fourth diode, wherein, a cathode of the third diode is connected with an anode of the fourth diode and a second end of the secondary side of the transformer module, and an anode of the third diode is connected with a cathode of the fourth diode and the ultrasonic transducer.

9. The transmit circuit for an ultrasonic transducer of claim 6, wherein, Further comprising: a resistance matching circuit, wherein, a first end and a second end of the resistance matching circuit are respectively connected with the second end of the first output shielding unit and the second end of the second output shielding unit.

10. An ultrasonic transducer, characterized by, comprise: the transmitting circuit of the ultrasonic transducer and the body of the ultrasonic transducer according to any one of claims 1-9.

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