Transducer

Abstract

A sensor includes a housing, a piezoelectric element, a buffer material, an acoustic matching layer, a transformer, a set of low-frequency connecting lines, a set of high-frequency connecting lines, and a matching capacitor. The transformer is disposed on top of the buffer material to boost or buck voltage signals and adjust the sensor's impedance. The set of low-frequency connecting lines is disposed on the primary side of the transformer for transmitting low-frequency signals, and the set of high-frequency connecting lines is disposed on the primary side of the transformer for transmitting high-frequency signals. The matching capacitor is disposed on the secondary side of the transformer for impedance and phase matching. The matching capacitor is adjusted such that the transformer has impedance and phase matching with the set of low-frequency connecting lines when transmitting low-frequency signals, and the transformer has impedance and phase matching with the set of high-frequency connecting lines when transmitting high-frequency signals.

Claims

1. A sensor, comprising: An outer casing is used to cover the sensor; A piezoelectric element for converting a sound wave signal into a voltage signal or vice versa; a buffer material for covering the piezoelectric element to direct the transmission and reception of the sound wave signal in a specific direction; a sound wave matching layer located between a bottom of the piezoelectric element and a bottom of the housing for adjusting the impedance of the sound wave signal; a transformer disposed on a top of the buffer material for boosting or bucking the voltage signal and adjusting the impedance of the sensor; a set of low-frequency connection lines disposed on the primary side of the transformer for transmitting a low-frequency signal; a set of high-frequency connection lines disposed on the primary side of the transformer for transmitting a high-frequency signal; and a matching capacitor disposed on the secondary side of the transformer for impedance and phase matching. The matching capacitor is adjusted so that the transformer has impedance and phase matching with the low-frequency connection line when transmitting the low-frequency signal, and the transformer has impedance and phase matching with the high-frequency connection line when transmitting the high-frequency signal.

2. The sensor as claimed in claim 1, wherein the piezoelectric element further includes a positive electrode and a negative electrode for outputting the voltage signal.

3. The sensor as described in claim 1, further comprising: A low-frequency matching circuit is configured in the group of low-frequency connection lines to perform impedance and phase matching of the low-frequency signal; and a high-frequency matching circuit is configured in the group of high-frequency connection lines to perform impedance and phase matching of the high-frequency signal.

4. The sensor as claimed in claim 3, wherein the low-frequency matching circuit includes a low-frequency capacitor and a low-frequency inductor connected in series or parallel, and the high-frequency matching circuit includes a high-frequency capacitor and a high-frequency inductor connected in series or parallel.

5. The sensor as claimed in claim 1, wherein the housing is made of metal or plastic.

6. The sensor as claimed in claim 1, wherein a material and a thickness of the acoustic matching layer are adjustable such that the thickness is 1 / 4 wavelength of an acoustic wave of the material, and the thickness is adjusted such that the impedance remains stable in a frequency band.

7. The sensor as claimed in claim 1, wherein the transformer comprises: An enameled wire is disposed on the primary side and the secondary side of the transformer; A core, positioned at an intermediate location in the transformer; a winding frame for placing the core and the enameled wire in a fixed position and for welding the low-frequency connecting wires and / or the high-frequency connecting wires; and an insulating tape, wound in two or more layers and positioned between the plurality of windings of the transformer and an outer layer.

8. The sensor as claimed in claim 7, wherein the winding method of the enameled wire and a coil of the winding frame is used to adjust a parasitic capacitance of the transformer so that the matching capacitor can achieve impedance and phase matching.

9. The sensor as claimed in claim 1, wherein the group of low-frequency connection lines and the group of high-frequency connection lines share a common ground wire.

10. The sensor as claimed in claim 1, wherein the set of low-frequency connection lines and the set of high-frequency connection lines are independent of each other and not collinear.

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