Physical amount detecting device

• US 8,539,833 B2
• Filed: 02/01/2011
• Issued: 09/24/2013
• Est. Priority Date: 03/26/2010
• Status: Expired due to Fees

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Amemiya, Masaki
• Primary Examiner(s): Macchiarolo, Peter
• Assistant Examiner(s): Shah, Samir M
• Application Number:
  US13/018,685
• Publication Number:
  US 20110232382A1
• Time in Patent Office: 966 Days
• Field of Search: 735/041.2, 735/041.5, 735/041.6, 310/370
• US Class Current: 73/504.12
• CPC Class Codes: G01C 19/5607 using vibrating tuning forks double-ended tuning forks using planar vibrating masses suspended at opposite ends G01C19/5719
• CPC Class Codes: G01C 19/5614 Signal processing
• CPC Class Codes: G01C 19/5621 the devices involving a micromechanical structure
• CPC Class Codes: G01C 19/5733 Structural details or topology

Abstract

A physical amount detecting device includes: one pair of driving vibration arms are bending-vibrated in a direction of a X-axis, one pair of first detection vibration arms and one pair of second detection vibration arms are vibrated in a direction of a Y axis, depending on a Coriolis force that is generated in accordance with rotational angular velocity of X-axis rotation, the one pair of the first detection vibration arms are bending-vibrated with a first phase in a direction of a Z axis in addition to vibration in the direction of the Y axis, and the one pair of the second detection vibration arms are bending-vibrated with a second phase, which is a phase opposite to the first phase, in the direction of the Z axis in addition to vibration in the direction of the Y axis.

Claims

1. A physical amount detecting device comprising:

a base portion;

one pair of connection arms that extend from the base portion in opposite directions along an X axis;

one pair of driving vibration arms that extend from the base portion in opposite directions along a Y axis;

one pair of first detection vibration arms that extend from one of the one pair of connection arms in opposite directions along the Y axis;

one pair of second detection vibration arms that extend from the other of the one pair of connection arms in opposite directions along the Y axis;

a driving signal electrode that is used for bending vibration of the one pair of driving vibration arms;

a driving ground electrode that forms a pair with the driving signal electrode;

a first detection signal electrode that is used for obtaining a detection signal from the one pair of the first detection vibration arms;

a first detection ground electrode that forms a pair with the first detection signal electrode;

a second detection signal electrode that is used for obtaining a detection signal from the one pair of the second detection vibration arms; and

a second detection ground electrode that forms a pair with the second detection signal electrode,

wherein one and the other of the one pair of the driving vibration arms are configured to be bending-vibrated with opposite phases in a direction of the X-axis,

the one pair of the first detection vibration arms and the one pair of the second detection vibration arms are configured to be vibrated with opposite phases in a direction of the Y axis in accordance with the bending vibration of the one pair of driving vibration arms,

depending on a Coriolis force that is generated in accordance with rotational angular velocity of X-axis rotation, one and the other of the one pair of the first detection vibration arms are configured to be bending-vibrated with a first phase in a direction of a Z axis in addition to vibration in the direction of the Y axis, and one and the other of the one pair of the second detection vibration arms are configured to be bending-vibrated with a second phase, which is a phase opposite to the first phase, in the direction of the Z axis in addition to vibration in the direction of the Y axis,

the base portion, the one pair of connection arms, the one pair of driving vibration arms, the one pair of the first detection vibration arms, and the one pair of the second detection vibration arms configure a piezoelectric vibrating reed,

the piezoelectric vibrating reed has a first primary face and a second primary face that are front and rear faces along a plane defined by the X axis and the Y axis,

the one pair of driving vibration arms has a first side face that connects the first primary face and the second primary face and a second side face that connects the first primary face and the second primary face and is located on a side opposite to the first side face,

the one pair of the first detection vibration arms has a third side face that connects the first primary face and the second primary face and faces the first side face and a fourth side face that connects the first primary face and the second primary face and is located on a side opposite to the third side face,

the one pair of the second detection vibration arms has a fifth side face that connects the first primary face and the second primary face and faces the second side face and a sixth side face that connects the first primary face and the second primary face and is located on a side opposite to the fifth side face,

the driving signal electrode is formed on the first and second primary faces of one of the one pair of the driving vibration arms and the first and second side faces of the other of the one pair of driving vibration arms,

the driving ground electrode is formed on the first and second side faces of one of the one pair of driving vibration arms and the first and second primary faces of the other of the one pair of driving vibration arms,

the first detection signal electrode is formed on the first primary face side of the fourth side face and the second primary face side of the third side face,

the first detection ground electrode is formed on the first primary face side of the third side face and the second primary face side of the fourth side face,

the second detection signal electrode is formed on the first primary face side of the fifth side face and the second primary face side of the sixth side face, and

the second detection ground electrode is formed on the first primary face side of the sixth side face and the second primary face side of the fifth side face.

2. The physical amount detecting device according to claim 1,

wherein the first detection signal electrode and the first detection ground electrode face each other through a first detection driving arm, and

wherein the second detection signal electrode and the second detection ground electrode face each other through a second detection driving arm.

3. A physical amount detecting apparatus comprising:

the physical amount detecting device according to claim 1;

a package in which the physical amount detecting device is housed; and

an IC chip that is used for controlling the physical amount detecting device.

4. A physical amount detecting device comprising:

a base portion;

one pair of connection arms that extend from the base portion in opposite directions along an X axis;

one pair of driving vibration arms that extend from the base portion in opposite directions along a Y axis;

one pair of first detection vibration arms that extend from one of the one pair of connection arms in opposite directions along the Y axis;

one pair of second detection vibration arms that extend from the other of the one pair of connection arms in opposite directions along the Y axis;

a driving signal electrode that is used for bending vibration of the one pair of driving vibration arms;

a driving ground electrode that forms a pair with the driving signal electrode;

a first detection signal electrode that is used for obtaining a detection signal from the one pair of the first detection vibration arms;

a first detection ground electrode that forms a pair with the first detection signal electrode;

a second detection signal electrode that is used for obtaining a detection signal from the one pair of the second detection vibration arms; and

a second detection ground electrode that forms a pair with the second detection signal electrode,

wherein one and the other of the one pair of the driving vibration arms are configured to be bending-vibrated with opposite phases in a direction of the X-axis,

the one pair of the first detection vibration arms and the one pair of the second detection vibration arms are configured to be vibrated with opposite phases in a direction of the Y axis in accordance with the bending vibration of the one pair of driving vibration arms,

depending on a Coriolis force that is generated in accordance with rotational angular velocity of X-axis rotation, one and the other of the one pair of the first detection vibration arms are configured to be bending-vibrated with a first phase in a direction of a Z axis in addition to vibration in the direction of the Y axis, and one and the other of the one pair of the second detection vibration arms are configured to be bending-vibrated with a second phase, which is a phase opposite to the first phase, in the direction of the Z axis in addition to vibration in the direction of the Y axis,

the base portion, the one pair of connection arms, the one pair of driving vibration arms, the one pair of the first detection vibration arms, and the one pair of the second detection vibration arms configure a piezoelectric vibrating reed,

the piezoelectric vibrating reed has a first primary face and a second primary face that are front and rear faces along a plane defined by the X axis and the Y axis,

the one pair of driving vibration arms has a first side face that connects the first primary face and the second primary face and a second side face that connects the first primary face and the second primary face and is located on a side opposite to the first side face,

the one pair of the first detection vibration arms has a third side face that connects the first primary face and the second primary face and faces the first side face and a fourth side face that connects the first primary face and the second primary face and is located on a side opposite to the third side face,

the one pair of the second detection vibration arms has a fifth side face that connects the first primary face and the second primary face and faces the second side face and a sixth side face that connects the first primary face and the second primary face and is located on a side opposite to the fifth side face,

a first groove is formed on the first primary face of the one pair of driving vibration arms,

a second groove is formed on the second primary face of the one pair of driving vibration arms,

a third groove is formed on the first primary face of the one pair of the first detection vibration arms,

a fourth groove is formed on the second primary face of the one pair of the first detection vibration arms,

a fifth groove is formed one the first primary face of the one pair of the second detection vibration arms,

a sixth groove is formed on the second primary face of the one pair of the second detection vibration arms,

the driving signal electrode is formed on inner faces of the first and second grooves of one of the one pair of driving vibration arms and the first and second side faces of the other of the one pair of driving vibration arms,

the driving ground electrode is formed on the first and second side faces of one of the one pair of driving vibration arms and the inner faces of the first and second grooves of the other of the one pair of driving vibration arms,

the first detection signal electrode is formed on the first primary face side of the fourth side face, the second primary face side of the third side face, an inner face of the third groove that is located on the third side face side, and an inner face of the fourth groove that is located on the fourth side face side,

the first detection ground electrode is formed on the first primary face side of the third side face, the second primary face side of the fourth side face, the inner face of the third groove that is located on the fourth side face side, and the inner face of the fourth groove that is located on the third side face side,

the second detection signal electrode is formed on the first primary face side of the fifth side face, the second primary face side of the sixth side face, an inner face of the fifth groove that is located on the sixth side face side, and an inner face of the sixth groove that is located on the fifth side face side, and

the second detection ground electrode is formed on the first primary face side of the sixth side face, the second primary face side of the fifth side face, the inner face of the fifth groove that is located on the fifth side face side, and the inner face of the sixth groove that is located on the sixth side face side.

5. The physical amount detecting device according to claim 4,

wherein the first detection signal electrode and the first detection ground electrode face each other through a first detection driving arm, and

wherein the second detection signal electrode and the second detection ground electrode face each other through a second detection driving arm.

6. A physical amount detecting apparatus comprising:

the physical amount detecting device according to claim 4;

a package in which the physical amount detecting device is housed; and

an IC chip that is used for controlling the physical amount detecting device.