SENSOR ASSEMBLY

• US 20090038403A1
• Filed: 08/07/2008
• Published: 02/12/2009
• Est. Priority Date: 08/08/2007
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Eguchi, Yoshimasa, Kamei, Takahiro
• Granted Patent: US 7,733,219 B2
• Time in Patent Office: Days
• US Class Current: 73/774
• CPC Class Codes: B60R 19/483 with obstacle sensors of electric or electronic type
• CPC Class Codes: B60R 21/0136 responsive to actual contact with an obstacle , e.g. to vehicle deformation, bumper displacement or bumper velocity relative to the vehicle monitoring crash strength in combination with passenger seat detection B60R21/01558
• CPC Class Codes: G01L 1/16 using properties of piezoelectric devices

Abstract

A sensor assembly includes a elongate article and a plurality of elongate piezoelectric elements provided to the elongate article. Each of the piezoelectric elements is configured so that when a load is applied in a direction perpendicular to a surface of the piezoelectric element, a short axis direction of the piezoelectric element becomes a sensitivity direction in which a voltage is generated, and a major axis direction becomes a non-sensitivity direction in which a voltage is not generated.

Claims

1. A sensor assembly, comprising:

a elongate article; and

a sensor element comprised of at least one elongate piezoelectric element disposed along a longitudinal direction of the elongate article,

wherein the sensor element is configured such that when a load acts in a direction that is perpendicular to a surface of the piezoelectric element, a short axis direction of the elongate sensor element becomes a sensitivity direction in which a voltage is generated, and a longitudinal direction that is a major axis direction becomes a non-sensitivity direction in which a voltage is not generated.

2. The sensor assembly of claim 1, further comprising:

a first member disposed even further frontward of a vehicle body than the sensor element and having a load-transmitting part extending toward the sensor element; and

a second member disposed between the first member and the vehicle body for supporting the sensor element,

wherein the first member and the second member are positioned relative to each other in a vertical direction using a positioning part, whereby the load-transmitting part is made to face the sensor elements.

3. The sensor assembly of claim 2, wherein the first member has a mounting part to be mounted to the vehicle body, and the mounting part is configured so as to limit movement of the first member and the vehicle body only to a direction away from each other.

4. The sensor assembly of claim 2, wherein the positioning part has a plurality of positioning holes formed in the second member and a plurality of insertion parts capable of being inserted into the positioning holes, and the insertion parts are introduced through the positioning holes, whereby the first member and the second member are positioned relative to each other in the vertical direction.

5. The sensor assembly of claim 4, wherein the load-transmitting part is provided to at least one area among areas above or below the insertion part.

6. The sensor assembly of claim 2, further comprising a plurality of mounting parts for mounting the first member to the vehicle body, wherein the load-transmitting part is positioned between the mounting parts and the insertion part provided on the first member.

7. The sensor assembly of claim 4, wherein the load-transmitting part and the sensor element are provided, respectively, above and below the insertion part.

8. The sensor assembly of claim 3, wherein the positioning part is provided between the mounting part and the second member.

9. The sensor assembly of claim 1, wherein the sensor element is comprised of a polyvinylidene fluoride piezoelectric film, and when the sensor element is disposed on the elongate article, the longitudinal direction of the sensor element is in alignment with the longitudinal direction of the elongate article.