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WO-2026092327-A1 - PIEZOELECTRIC SENSOR, PIEZOELECTRIC CERAMIC APPARATUS AND ELECTRONIC DEVICE

WO2026092327A1WO 2026092327 A1WO2026092327 A1WO 2026092327A1WO-2026092327-A1

Abstract

Provided in the present application are a piezoelectric sensor, a piezoelectric ceramic apparatus and an electronic device. The piezoelectric sensor comprises a first piezoelectric ceramic, a conductive member and a second piezoelectric ceramic, wherein the first piezoelectric ceramic and the second piezoelectric ceramic are both connected to the conductive member, and the polarization directions of the first piezoelectric ceramic and the second piezoelectric ceramic in a first direction are opposite. The piezoelectric sensor enables electrical signals, which are generated by the first piezoelectric ceramic and the second piezoelectric ceramic due to temperature changes, to cancel each other, so as to ensure the detection reliability and detection accuracy of the piezoelectric sensor, thereby ensuring the measurement sensitivity and measurement accuracy of a subsequent-stage circuit for measuring a quasi-static force.

Inventors

  • ZHU, Botong

Assignees

  • 广州视源电子科技股份有限公司
  • 广州视睿电子科技有限公司

Dates

Publication Date
20260507
Application Date
20251024
Priority Date
20241028

Claims (10)

  1. A piezoelectric sensor (1) is characterized by comprising a first piezoelectric ceramic (11), a conductive element (12), and a second piezoelectric ceramic (13). The first piezoelectric ceramic (11) and the second piezoelectric ceramic (13) are respectively connected to the conductive element (12), and the polarization directions of the first piezoelectric ceramic (11) and the second piezoelectric ceramic (13) are opposite in the first direction.
  2. According to claim 1, the piezoelectric sensor (1) is characterized in that the first piezoelectric ceramic (11) and the second piezoelectric ceramic (13) are respectively attached to the two opposite sides of the conductive element (12) in the first direction.
  3. According to claim 2, the piezoelectric sensor (1) is characterized in that the piezoelectric sensor (1) further includes a heat-conducting element (14), the heat-conducting element (14) is located between the first piezoelectric ceramic (11) and the conductive element (12), and is connected to the first piezoelectric ceramic (11) and the conductive element (12); or, The heat-conducting element (14) is located between the second piezoelectric ceramic (13) and the conductive element (12), and is connected to the second piezoelectric ceramic (13) and the conductive element (12).
  4. According to claim 3, the piezoelectric sensor (1) is characterized in that the material of the heat-conducting element (14) includes any one of conductive copper foil, thermally conductive gel and ceramic material.
  5. According to claim 1, the piezoelectric sensor (1) is characterized in that the first piezoelectric ceramic (11) and the second piezoelectric ceramic (13) are disposed adjacent to each other on one side of the conductive element (12) along a second direction; Wherein, the first direction intersects with the second direction.
  6. The piezoelectric sensor (1) according to any one of claims 1-5 is characterized in that the material of the conductive element (12) includes any one of copper alloy, nickel alloy, iron alloy, titanium alloy and conductive glass fiber board.
  7. A piezoelectric ceramic device, characterized in that it comprises: The piezoelectric sensor (1) as described in any one of claims 1-6; and, A fixed structure (2) is fixedly connected to at least one end of the piezoelectric sensor (1).
  8. According to claim 7, the piezoelectric ceramic device is characterized in that the fixing structure (2) comprises: A cantilever beam (21) is fixedly connected to at least one end of the piezoelectric sensor (1) along a second direction.
  9. According to claim 7, the piezoelectric ceramic device is characterized in that the fixing structure (2) comprises: Two simply supported beams (22) are fixedly connected to the two ends of the piezoelectric sensor (1) along the second direction.
  10. An electronic device, characterized in that the electronic device comprises a piezoelectric ceramic device as described in any one of claims 7 to 9.

Description

Piezoelectric sensors, piezoelectric ceramic devices and electronic equipment Related applications This application claims priority to the following Chinese patent application: Chinese patent application No. 202411509560X, filed on October 28, 2024, entitled "Piezoelectric Sensor, Piezoelectric Ceramic Device and Electronic Equipment", the entire contents of which are incorporated herein by reference. Technical Field This application relates to the field of force measurement technology, and more specifically, to a piezoelectric sensor, a piezoelectric ceramic device, and an electronic device. Background Technology In some electronic devices, touchpads are usually configured as interactive input devices to interact with users. Among them, piezoelectric sensors are the core sensor components in touchpads, which can detect changes in pressure applied by the user to the touchpad surface to achieve force-sensitive input. However, the piezoelectric ceramic in a piezoelectric sensor may experience temperature drift due to temperature variations, which can affect the sensor's detection performance and measurement accuracy. Summary of the Invention To address the aforementioned issues, this application provides a piezoelectric sensor, a piezoelectric ceramic device, and an electronic device, aiming to resolve the problem that piezoelectric ceramics may experience temperature drift due to temperature variations, which in turn affects the detection performance and measurement accuracy of the piezoelectric sensor. In a first aspect, this application provides a piezoelectric sensor, which includes a first piezoelectric ceramic, a conductive element, and a second piezoelectric ceramic; the first piezoelectric ceramic and the second piezoelectric ceramic are respectively connected to the conductive element, and the polarization directions of the first piezoelectric ceramic and the second piezoelectric ceramic are opposite in a first direction. Based on the piezoelectric sensor of this application embodiment, when the piezoelectric sensor is not subjected to force, since the polarization directions of the first and second piezoelectric ceramics are opposite in the first direction, the electrical signals generated by the temperature changes of the first and second piezoelectric ceramics can cancel each other out. This avoids the problem that temperature drift in the piezoelectric ceramics could cause the piezoelectric sensor to release charge when not under force, affecting the detection effect and measurement accuracy of the piezoelectric sensor, and consequently causing the test baseline in the subsequent circuit (e.g., the piezoelectric ceramic static force detection system) to drift, affecting the measurement sensitivity of quasi-static force. Thus, by canceling out the electrical signals generated by the temperature changes of the first and second piezoelectric ceramics, the detection reliability and accuracy of the piezoelectric sensor can be guaranteed, thereby ensuring the measurement sensitivity and accuracy of the subsequent circuit in measuring quasi-static force. When the piezoelectric sensor is subjected to a force in the first direction, the first piezoelectric ceramic generates a corresponding charge based on the pressure it receives and transfers the charge to the charge amplifier in the subsequent circuit. At the same time, the second piezoelectric ceramic also generates a corresponding charge based on the pressure it receives and transfers the charge to the charge amplifier in the subsequent circuit. That is, the charge received by the charge amplifier at this time contains dual signals. The charge amplifier can perform detection based on these dual signals, which improves the detection reliability of the piezoelectric sensor and thus ensures the measurement sensitivity and accuracy of the subsequent circuit in measuring quasi-static force. In one possible implementation, the first piezoelectric ceramic and the second piezoelectric ceramic are respectively bonded to the two opposite sides of the conductive element in a first direction. In this implementation, the charges generated by the pyroelectric effect of the first and second piezoelectric ceramics are in opposite directions. Thus, there is no potential difference or charge flow between the first and second output signal lines, allowing the electrical signals generated by the temperature changes of the first and second piezoelectric ceramics to cancel each other out. This ensures the reliability and accuracy of the piezoelectric sensor, thereby guaranteeing the sensitivity and accuracy of the subsequent circuitry in measuring quasi-static forces. Simultaneously, when the first and second piezoelectric ceramics are subjected to external forces (such as pressure or vibration), the voltages generated by them are in the same direction. This allows the useful signals generated by the first and second piezoelectric ceramics to be superimposed, improving the