Vibrator of vibratory drive unit, vibratory drive unit, interchangeable lens, imaging device, and automatic stage

Patent metadata

Field	Value
Publication number	US-9507119-B2
Application number	US-201414515272-A
Country	US
Kind code	B2
Filing date	Oct 15, 2014
Priority date	Oct 16, 2013
Publication date	Nov 29, 2016
Grant date	Nov 29, 2016

Abstract

A vibrator including an electro-mechanical transducer and an elastic body that is fixed to the electro-mechanical transducer and that is provided with a projection, the projection having a hollow structure. The projection includes a contact portion having a first surface at a tip, the first surface being parallel to a first plane, a wall portion projecting towards an opposite side with respect to the electro-mechanical transducer, and a connection portion connecting the wall portion and the contact portion to each other. The connection portion having a spring property, and the contact portion includes a portion of which a cross-sectional area in a second plane that is parallel to the first plane increases as an increase of a distance between the portion and the first surface.

First claim

What is claimed is:

1. A vibrator, comprising:
an electro-mechanical transducer; and
an elastic body that is fixed to the electro-mechanical transducer and that is provided with a projection having a hollow structure,
wherein the projection includes:
a contact portion having a contact surface at a tip;
a wall portion projecting towards an opposite side with respect to the electro-mechanical transducer; and
a connection portion connecting the wall portion and the contact portion to each other, the connection portion having a spring property, and

wherein a cross-sectional area of a root portion of the contact portion is larger than a cross-sectional area of the contact surface.

2. The vibrator according to claim 1 , wherein
a cross-sectional shape of the contact portion has a substantially trapezoid shape.

3. The vibrator according to claim 1 , wherein
the hollow structure of the projection is formed in a cylindrical shape.

4. The vibrator according to claim 3 , wherein
a change in a spring stiffness of the projection in a case in which a thickness of the contact portion is decreased due to wear caused by being in contact with a driven body is 10% or less.

5. The vibrator according to claim 4 , wherein
a diameter of the root portion of the contact portion is 2 times or more larger than a diameter of the contact surface.

6. The vibrator according to claim 4 , wherein
in a case in which a diameter of the contact surface is 0.3 mm and a diameter of the root surface constituting the largest diameter of the contact portion is 1.5 mm, a range of decrease in thickness due to wear is in the range of 40 μm or less.

7. The vibrator according to claim 1 , wherein
the elastic body is configured so that the contact surface is in contact with a driven body.

8. The vibrator according to claim 1 , wherein
the vibrator is configured so that, by application of an AC voltage to the electro-mechanical transducer, the vibrator and a driven body that is in contact with the contact surface are relatively displaced with respect to each other.

9. The vibrator according to claim 1 , wherein
the vibrator is configured so that, by application of an AC voltage to the electro-mechanical transducer, an ellipsoidal motion is excited in the projection.

10. The vibrator according to claim 9 , wherein
in the electro-mechanical transducer, the ellipsoidal motion is excited by two vibration modes.

11. The vibrator according to claim 10 , wherein
the two vibration modes are a first bending mode and a second bending mode, nodal lines of which are substantially orthogonal to each other.

12. The vibrator according to claim 1 , wherein
the electro-mechanical transducer has a rectangular shape in a first plane.

13. A vibratory drive unit, comprising:
the vibrator according to claim 1 ; and
a driven body that is in press-contact with the vibrator.

14. An interchangeable lens, comprising:
a lens;
a lens holder configured to hold the lens; and
the vibratory drive unit according to claim 13 that is provided in the lens holder.

15. An imaging device, comprising:
an imaging element; and
the vibratory drive unit according to claim 13 that is capable of displacing the imaging element.

16. An automatic stage, comprising:
the vibratory drive unit according to claim 13 ; and
a stage that is capable of being displaced with the vibratory drive unit.

17. A vibratory drive unit, comprising:
a vibrator including an electro-mechanical transducer and an elastic body; and
a movable member configured to contact the vibrator,
wherein the elastic body is provided with a projection protruding at a side opposite to a side at which the electro-mechanical transducer is provided, and a contact portion that protrudes along a direction in which the projection protrudes and configured to contact the movable member is provided to a part of the projection, and
wherein a cross-sectional area of a base of the contact portion is larger than a cross-sectional area of a top of the contact portion.

18. An electronic device comprising the vibratory drive unit according to claim 17 .

Assignees

• Canon Kk

Inventors

• Araki Yasuyuki

Classifications

• G02B21/26

  Stages; Adjusting means therefor · CPC title

• H02N2/0065

  Friction interface (friction linings F16D69/00) · CPC title

• G03B13/36

  Autofocus systems · CPC title

• H02N2/026

  by pressing one or more vibrators against the driven body · CPC title

• G02B7/09 Primary

  adapted for automatic focusing or varying magnification · CPC title