Piezoelectric element unit and driving device

Patent metadata

Field	Value
Publication number	US-9691964-B2
Application number	US-201514604271-A
Country	US
Kind code	B2
Filing date	Jan 23, 2015
Priority date	Feb 27, 2014
Publication date	Jun 27, 2017
Grant date	Jun 27, 2017

Abstract

A piezoelectric element unit comprises an element body having an active part and an inactive part; and a first resin part bonding one end surface in the laminating direction of the element body to a mounting surface of a joint member placed to face the one end surface. The first resin part covers the mounting surface up to an outer side surface of the element body corresponding to an interface between the active part and the inactive part, a second resin part covers an outer surface of the first resin part covering the outer side surface of the element body at a position corresponding to the interface between the active part and the inactive part, and the second resin part also integrally covers the outer side surface of the element body corresponding to the active part.

First claim

The invention claimed is:

1. A piezoelectric element unit comprising:
an element body having an active part in which piezoelectric layers and internal electrodes are laminated alternatively and an inactive part laminated at both ends of the active part in a laminating direction; and
a first resin part bonding one end surface in the laminating direction of the element body to a mounting surface of a joint member placed to face the one end surface, wherein
the first resin part covers the mounting surface up to an outer side surface of the element body corresponding to an interface between the active part and the inactive part,
a second resin part covers an outer surface of the first resin part covering the outer side surface of the element body at a position corresponding to the interface between the active part and the inactive part, and
the second resin part also integrally covers the outer side surface of the element body corresponding to the active part.

2. The piezoelectric element unit as set forth in claim 1 , wherein
an elastic modulus of the first resin part is larger than that of the second resin part.

3. The piezoelectric element unit as set forth in claim 1 , wherein
external electrodes are respectively formed on two opposite side surfaces of the element body and
the second resin part also covers outer surfaces of the external electrodes.

4. The piezoelectric element unit as set forth in claim 2 , wherein
external electrodes are respectively formed on two opposite side surfaces of the element body and
the second resin part also covers outer surfaces of the external electrodes.

5. The piezoelectric element unit as set forth in claim 3 , wherein
a lead part for wiring is fixed by an electric connection part to nearby the mounting surface on the outer surfaces of the external electrodes and
the electric connection part is doubly covered by the first resin part and the second resin part.

6. The piezoelectric element unit as set forth in claim 4 , wherein
a lead part for wiring is fixed by an electric connection part to nearby the mounting surface on the outer surfaces of the external electrodes and
the electric connection part is doubly covered by the first resin part and the second resin part.

7. The piezoelectric element unit as set forth in claim 3 , wherein
a lead part for wiring is fixed by an electric connection part to the outer surfaces of the external electrodes corresponding to the active part and
the electric connection part is covered by the second resin part.

8. The piezoelectric element unit as set forth in claim 4 , wherein
a lead part for wiring is fixed by an electric connection part to the outer surfaces of the external electrodes corresponding to the active part and
the electric connection part is covered by the second resin part.

9. The piezoelectric element unit as set forth in claim 5 , wherein
the electric connection part is either a solder or a conductive adhesive agent.

10. The piezoelectric element unit as set forth in claim 6 , wherein
the electric connection part is either a solder or a conductive adhesive agent.

11. The piezoelectric element unit as set forth in claim 7 , wherein
the electric connection part is either a solder or a conductive adhesive agent.

12. The piezoelectric element unit as set forth in claim 8 , wherein
the electric connection part is either a solder or a conductive adhesive agent.

13. The piezoelectric element unit as set forth in claim 1 , wherein
the joint member is either a weight or a driving shaft.

14. The piezoelectric element unit as set forth in claim 1 , wherein
the second resin part is composed of a heat shrinkable tube.

15. A driving device comprising the piezoelectric element unit as set forth in claim 1 .

Assignees

• Tdk Corp

Inventors

• Ozawa Satoshi
• Tamura Atsushi
• Abe Akio
• Shimazaki Kohsuke
• Taguchi Haruo

Classifications

• H02N2/025 Primary

  Inertial sliding motors · CPC title

• H01L41/083

  Electricity · mapped topic

• H01L41/0533 Primary

  Electricity · mapped topic

• H01L41/313

  Electricity · mapped topic

• H10N30/50

  having a stacked or multilayer structure · CPC title