Movement detector

• US 20090033178A1
• Filed: 08/01/2008
• Published: 02/05/2009
• Est. Priority Date: 08/02/2007
• Status: Active Grant

• Current Assignee: Brother Kogyo Kabushiki Kaisha (Brother Industries Limited)
• Original Assignee: Brother Kogyo Kabushiki Kaisha (Brother Industries Limited)
• Inventors: Sugahara, Hiroto
• Granted Patent: US 7,839,057 B2
• Time in Patent Office: Days
• US Class Current: 310/338
• CPC Class Codes: B41J 29/00 Details of, or accessories for, typewriters or selective printing mechanisms not otherwise provided for
• CPC Class Codes: B41J 29/38 Drives, motors, controls or automatic cut-off devices for the entire printing mechanism
• CPC Class Codes: G01D 5/185 using piezoelectric sensors
• CPC Class Codes: H10N 30/302 Sensors

Abstract

A movement detector which is rotatably installed on a base member includes a rotating member which has a body portion, and a connecting portion which rotatably connects the body portion to the base member, a piezoelectric layer which is formed on the connecting portion, and a plurality of electrodes which are provided on the piezoelectric layer, to be arranged in a direction of a rotation axis of the body portion, and which detect a voltage generated in the piezoelectric layer corresponding to a deformation of the connecting portion when the body portion has displaced with respect to the base member. Since the piezoelectric layer and the plurality of electrodes are provided to the connecting portion which rotatably connects the body portion to the base member, it is possible to detect a plurality of types of movements of the body portion by the piezoelectric layer and the plurality of electrodes.

Claims

1. A movement detector which is rotatably attached to a base member, comprising:

a rotating member which has a body portion, and a connecting portion which rotatably connects the body portion to the base member;

a piezoelectric layer which is formed on the connecting portion; and

a plurality of electrodes which are provided on the piezoelectric layer and arranged in a direction of a rotation axis of the body portion, and which detect a voltage generated in the piezoelectric layer corresponding to a deformation of the connecting portion when the body portion is displaced with respect to the base member.

2. The movement detector according to claim 1, wherein the piezoelectric layer is formed as a plurality of piezoelectric layers which are arranged in the direction of the rotation axis of the body portion, and each of the plurality of electrodes are formed on one of the piezoelectric layers.

3. The movement detector according to claim 2, further comprising a detector which detects a movement of the body portion based on the voltage detected by the electrodes.

4. The movement detector according to claim 2, wherein the connecting portion has a plurality of element installing portions on which the plurality of piezoelectric layers are formed respectively, and the element installing portions are arranged to be mutually separated in the direction of the rotation axis of the body portion.

5. The movement detector according to claim 4, wherein the element installing portion is formed of a metallic material, and a predetermined electric potential is always applied to the element installing portion.

6. The movement detector according to claim 1, wherein a thickness of the connecting portion is less than a thickness of the body portion.

7. The movement detector according to claim 1, wherein the connecting portion is formed of a metallic material.

8. The movement detector according claim 2, wherein the detector detects a direction of rotation of the body portion based on a polarity of a voltage signal detected by the electrodes.

9. The movement detector according to claim 2, wherein the detector detects a movement speed of the body portion based on a magnitude of a voltage signal detected by the electrodes.

10. The movement detector according to claim 2, wherein the detector detects a component of movement in a direction, which is different from a direction orthogonal to the direction of the rotation axis of the body portion, based on a difference in voltage signals detected by the electrodes.

11. The movement detector according to claim 2, further comprising a voltage applying section which applies an alternating voltage to at least one of the plurality of electrodes to vibrate the body portion.

12. The movement detector according to claim 2, wherein the movement detector is provided on a printer having an image display section which displays images of image data, an image recording section which records, on a recording medium, an image of an image datum among the image data selected, and a controller which controls the image display section and the image recording section;

and

the body portion is rotatably connected to an attachment surface provided on a printer body, via the connecting portion, and

the piezoelectric layers and the electrodes formed on the connecting portion output, to the controller, a signal for changing the image data to be displayed on the image display section, or output a signal for selecting the image data which is displayed on the image display section, according to a deformation of the connecting portion when the body portion is operated.

13. The movement detector according to claim 2, wherein the movement detector is provided on a channel forming member having a channel through which a fluid flows, and

the body portion is arranged inside the channel to make contact with the fluid, and is rotatably connected to a surface inside the channel via the connecting portion.