Vibrating micro-mechanical sensor of angular velocity

• US 8,904,865 B2
• Filed: 03/02/2010
• Issued: 12/09/2014
• Est. Priority Date: 03/02/2009
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Electronics OY (Murata Manufacturing Co Limited)
• Inventors: Blomqvist, Anssi, Ruohio, Jaakko
• Primary Examiner(s): KWOK, HELEN C
• Application Number:
  US12/715,767
• Publication Number:
  US 20100218605A1
• Time in Patent Office: 1,743 Days
• Field of Search: 735/041.2, 735/041.4, 735/041.6, 735/040.2, 735/040.4
• US Class Current: 73/504.12
• CPC Class Codes: G01C 19/5747 each sensing mass being connected to a driving mass, e.g. driving frames

Abstract

The invention relates to measuring devices used for measuring angular velocity, and more precisely, to vibrating micro-mechanical sensors of angular velocity. The sensor of angular velocity according to the invention comprises at least two seismic mass structures (1), (2), excitation structures (3), (4) and coupling seesaw type springs (6), (7). The objective of the invention is to provide an improved sensor structure, which enables reliable measuring with good efficiency particularly in small vibrating micro-mechanical angular velocity sensor solutions.

Claims

1. A vibrating micro-mechanical sensor of angular velocity comprising:

a plurality of anchor points;

at least two excitation structures connected to and supported by first springs connected to the anchor points, wherein at least one of the first springs is a coupling seesaw type spring that couples the at least two excitation structures with a stiff support structure configured to rotate in a surface plane about a fixed axis that is perpendicular to the surface plane; and

at least two seismic mass structures positioned apart from each other and connected to and suspended by the excitation structures via a plurality of second springs,

wherein the stiff support structure is configured to force the excitation structures into opposite phase vibration in the surface plane, and

wherein paths of motion of the excitation structures while in the opposite phase vibration form two parallel arcs or lines in opposite directions side by side in the surface plane.

2. The sensor of claim 1, further comprising excitation comb structures positioned between the excitation structures.

3. The sensor of claim 2, wherein the excitation comb structures are supported by an anchoring structure located at a center of the sensor.

4. The sensor of claim 1, further comprising quadrature motion compensation comb structures positioned between the excitation structures.

5. The sensor of claim 1, further comprising detection comb structures configured to perform dual differential detection of Coriolis forces caused by angular velocity.