Piezoelectric actuator device, image pickup unit and mobile terminal apparatus
View Patent ↗An actuator device includes: a piezoelectric element; a weight secured to one end of the piezoelectric element along an expansion-contraction direction thereof; and a drive member secured to another end of the piezoelectric element. The piezoelectric element and the weight are in contact so as to have a spatial overlap with respect to the expansion-contraction direction of the piezoelectric element, and the center of gravity of the weight is positioned in the vicinity of a plane that contains a contact plane in which the piezoelectric element and the weight are in contact.
1. An actuator device comprising:
a piezoelectric element;
a weight secured to one end of the piezoelectric element along an expansion-contraction direction thereof; and
a drive member secured to another end of the piezoelectric element along the expansion-contraction direction, wherein:
the piezoelectric element and the weight are in contact so that the piezoelectric element has a spatial overlap, with respect to the expansion-contraction direction, with the weight, and
the center of gravity of the weight is positioned in the vicinity of a plane that contains a contact plane in which the piezoelectric element and the weight are in contact.
2. An actuator device comprising:
a piezoelectric element having a recessed part;
a weight having a flat part secured to one end of the piezoelectric element along an expansion-contraction direction thereof, and a protruding part accommodated in the recessed part of the piezoelectric element; and
a drive member secured to another end of the piezoelectric element along the expansion-contraction direction, wherein
the center of gravity of the weight is positioned in the vicinity of a plane that contains a contact plane in which the piezoelectric element and the weight are in contact.
3. An actuator device comprising:
a piezoelectric element;
a weight having a recessed part for accommodating a portion of the piezoelectric element, the weight secured to one end of the piezoelectric element along an expansion-contraction direction thereof at a bottom face of the recessed part; and
a drive member secured to another end of the piezoelectric element along the expansion-contraction direction, wherein
the center of gravity of the weight is positioned in the vicinity of a plane that contains a contact plane in which the piezoelectric element and the weight are in contact.
4. The actuator device as set forth in claim 1 , wherein the piezoelectric element and the weight are disposed substantially coaxially with each other.
5. An image pickup unit comprising:
an actuator device comprising: a piezoelectric element; a weight secured to one end of the piezoelectric element along an expansion-contraction direction thereof; and a drive member secured to another end of the piezoelectric element along the expansion-contraction direction, wherein the piezoelectric element and the weight are in contact so that the piezoelectric element has a spatial overlap, with respect to the expansion-contraction direction, with the weight, and the center of gravity of the weight is positioned in the vicinity of a plane that contains a contact plane in which the piezoelectric element and the weight are in contact;
an engaging member for engaging the drive member and a lens-barrel for retaining a lens; and
an image pickup element for converting light from the lens into an electric signal, wherein
the lens-barrel moves in an optical axis direction of the lens according to expansion and contraction of the piezoelectric element.
6. The image pickup unit as set forth in claim 5 , wherein an imaging magnification of the image pickup element for the image pickup plane is varied by movement of the lens-barrel for retaining the lens in an optical axis direction.
7. A mobile terminal apparatus comprising an image pickup unit as set forth in claim 5 .
8. An actuator device comprising:
a piezoelectric element;
a weight secured to one end of the piezoelectric element along an expansion-contraction direction thereof; and
a drive member secured to another end of the piezoelectric element along the expansion-contraction direction, wherein
the drive member and the piezoelectric element are in contact so that the drive member has a spatial overlap, with respect to the expansion-contraction direction, with the piezoelectric element and the weight.
9. An actuator device comprising:
a piezoelectric element;
a weight secured to one end of the piezoelectric element along an expansion-contraction direction thereof; and
a drive member secured to another end of the piezoelectric element along the expansion-contraction direction, wherein
the drive member has a recessed part for accommodating at least a portion of the piezoelectric element and the weight, with respect to the expansion-contraction direction.
10. The actuator device as set forth in claim 8 , wherein the center of gravity of the drive member is positioned in the vicinity of a plane that contains a contact plane in which the piezoelectric element and the weight are in contact.
11. The actuator device as set forth in claim 8 , wherein the piezoelectric element and the weight are in contact so as to have the spatial overlap with respect to the expansion-contraction direction.
12. The actuator device as set forth in claim 8 , wherein the weight has a recessed part for accommodating at least a portion of the piezoelectric element with respect to the expansion-contraction direction of the piezoelectric element.
13. The actuator device as set forth in claim 11 , wherein the center of gravity of the weight is positioned in the vicinity of a plane that contains a contact plane in which the piezoelectric element and the weight are in contact.
14. The actuator device as set forth in claim 8 , wherein the drive member, the piezoelectric element, and the weight are disposed substantially coaxially with each other.
15. An image pickup unit comprising:
an actuator device comprising: a piezoelectric element; a weight secured to one end of the piezoelectric element along an expansion-contraction direction thereof; and a drive member secured to another end of the piezoelectric element along the expansion-contraction direction, wherein the drive member and the piezoelectric element are in contact so that the drive member has a spatial overlap, with respect to the expansion-contraction direction, with the piezoelectric element and the weight;
an engaging member for engaging the drive member and a lens-barrel for retaining a lens; and
an image pickup element for converting light from the lens into an electric signal, wherein
the lens-barrel moves in an optical axis direction of the lens according to expansion and contraction of the piezoelectric element.
16. The image pickup unit as set forth in claim 15 , wherein, in the actuator device, the center of gravity of the drive member is positioned in the vicinity of a plane that contains a contact plane in which the piezoelectric element and the weight are in contact.
17. The image pickup unit as set forth in claim 15 , wherein an imaging magnification of the image pickup element for the image pickup plane is varied by movement of the lens-barrel for retaining the lens in an optical axis direction.
18. A mobile terminal apparatus comprising an image pickup unit as set forth in claim 15 .
19. An actuator device comprising:
a piezoelectric element;
a weight secured to one end of the piezoelectric element along an expansion-contraction direction thereof; and
a drive member secured to another end of the piezoelectric element along the expansion-contraction direction, wherein
the piezoelectric element and the weight are in contact so that the piezoelectric element has a spatial overlap, with respect to the expansion-contraction direction, with the weight.
20. An actuator device comprising:
a piezoelectric element having a recessed part;
a weight having a flat part secured to one end of the piezoelectric element along an expansion-contraction direction thereof, and a protruding part accommodated in the recessed part of the piezoelectric element; and
a drive member secured to another end of the piezoelectric element along the expansion-contraction direction.
21. An actuator device comprising:
a piezoelectric element;
a weight having a recessed part for accommodating at least a portion of the piezoelectric element, the weight secured to one end of the piezoelectric element along an expansion-contraction direction thereof at a bottom face of the recessed part; and
a drive member secured to another end of the piezoelectric element along the expansion-contraction direction.
22. The actuator device as set forth in claim 19 , wherein the piezoelectric element and the weight are disposed substantially coaxially with each other.
23. An image pickup unit comprising:
an actuator device comprising: a piezoelectric element; a weight secured to one end of the piezoelectric element along an expansion-contraction direction thereof; and a drive member secured to another end of the piezoelectric element along the expansion-contraction direction, wherein the piezoelectric element and the weight are in contact so that the piezoelectric element has a spatial overlap, with respect to the expansion-contraction direction, with the weight;
an engaging member for engaging the drive member and a lens-barrel for retaining a lens; and
an image pickup element for converting light from the lens into an electric signal, wherein
the lens-barrel moves in an optical axis direction of the lens according to expansion and contraction of the piezoelectric element.
24. The image pickup unit as set forth in claim 23 , wherein an imaging magnification of the image pickup element for the image pickup plane is varied by movement of the lens-barrel for retaining the lens in an optical axis direction.
25. A mobile terminal apparatus comprising an image pickup unit as set forth in claim 23 .
26. The actuator device as set forth in claim 2 , wherein the piezoelectric element and the weight are disposed substantially coaxially with each other.
27. The actuator device as set forth in claim 3 , wherein the piezoelectric element and the weight are disposed substantially coaxially with each other.
28. The actuator device as set forth in claim 20 , wherein the piezoelectric element and the weight are disposed substantially coaxially with each other.
29. The actuator device as set forth in claim 21 , wherein the piezoelectric element and the weight are disposed substantially coaxially with each other.