TRI-AXIS ACCELEROMETER HAVING A SINGLE PROOF MASS AND FULLY DIFFERENTIAL OUTPUT SIGNALS

• US 20140102194A1
• Filed: 03/14/2013
• Published: 04/17/2014
• Est. Priority Date: 08/30/2006
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: ULM, Markus, PAN, Zhiyu, LANG, Christoph, YAMA, Gary, METZ, Matthias
• Granted Patent: US 9,003,885 B2
• Time in Patent Office: Days
• US Class Current: 73/514.01
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/09 by piezoelectric pick-up
• CPC Class Codes: G01P 15/123 by piezo-resistive elements, e.g. semiconductor strain gauges
• CPC Class Codes: G01P 15/18 in two or more dimensions
• CPC Class Codes: G01P 2015/084 the mass being suspended at more than one of its sides, e.g. membrane-type suspension, so as to permit multi-axis movement of the mass
• CPC Class Codes: Y10T 29/42 Piezoelectric device making

Abstract

A tri-axis accelerometer includes a proof mass, at least four anchor points arranged in at least two opposite pairs, a first pair of anchor points being arranged opposite one another along a first axis, a second pair of anchor points being arranged opposite one another along a second axis, the first axis and the second axis being perpendicular to one another, and at least four spring units to connect the proof mass to the at least four anchor points, the spring units each including a pair of identical springs, each spring including a sensing unit.

Claims

1-9. -9. (canceled)

10. A tri-axis accelerometer, comprising:

a proof mass;

a plurality of anchor points arranged in at least two pairs opposite one another along at least two axial directions that are perpendicular to one another; and

a plurality of spring units to connect the proof mass to the plurality of anchor points, the spring units each including a pair of identical springs, each spring including a sensing unit.

11. The tri-axis accelerometer of claim 10, wherein the pair of identical springs are arranged to detect a fully differential output signal.

12. The tri-axis accelerometer of claim 11, wherein the pair of identical springs are arranged parallel to each other and perpendicular with respect to a longitudinal axis along the connection between the proof mass and a respective anchor point.

13. The tri-axis accelerometer of claim 11, further comprising:

only one pick-up circuitry to detect the fully differential output signal of each pair of identical springs.

14. The tri-axis accelerometer of claim 10, wherein the proof mass, plurality of anchor points, and plurality of springs are arranged on one monolithic microchip.

15-20. -20. (canceled)