TRI-AXIS ACCELEROMETER

• US 20110303009A1
• Filed: 01/28/2011
• Published: 12/15/2011
• Est. Priority Date: 06/11/2010
• Status: Abandoned Application

• Current Assignee: AAC Acoustic Technologies Company Limited, American Audio Components, Inc.
• Original Assignee: AAC Acoustic Technologies Company Limited, American Audio Components, Inc.
• Inventors: Yang, Bin, Zhang, Rui, Ge, Zhou, Meng, Zhen-kui, Yan, Yi-lin
• Application Number:
  US13/015,927
• Publication Number:
  US 20110303009A1
• Time in Patent Office: Days
• US Class Current: 73/514.32
• CPC Class Codes: G01P 15/125 by capacitive pick-up
• CPC Class Codes: G01P 15/18 in two or more dimensions

Abstract

An tri-axis accelerometer is disclosed. The tri-axis accelerometer includes a mass, a first group of capacitance, a third group of capacitance being neighbor to the first group of capacitance. The mass defines an upper surface, a lower surface parallel to the upper surface and a side wall connecting the upper surface and the lower surface. The first group of capacitance includes a first movable electrode and the third group of capacitance includes a third movable electrode. The first movable electrode is perpendicular to the third movable electrode.

Claims

1. A tri-axis accelerometer comprising

a mass, a first group of capacitance, a third group of capacitance being neighbor to the first group of capacitance, the mass defining an upper surface, a lower surface being parallel to the upper surface and a side wall connecting the upper surface and the lower surface;

the first group of capacitance comprising

a first movable electrode axis connected to the side wall,

a first spring supporting member connecting the first movable electrode axis;

a plurality of first movable electrodes perpendicularly extending from the first movable electrode axis;

a plurality of first fixing electrodes being parallel to the first movable electrodes,

at least one first movable electrode located between two adjacent first fixing electrodes and at least one first fixing electrode located between two adjacent first movable electrodes;

the first movable electrode defining a first top surface and a first lower surface being parallel to the upper surface, a first side wall connecting the first top surface and the first lower surface;

the first fixing electrode defining a second top surface and a second lower surface being parallel to the upper surface, a second side wall connecting the second top surface and the second lower surface;

the first top surface being closer to the upper surface than the second top surface, and the first lower surface being closer to the upper surface than the second lower surface;

the third group of capacitance comprising;

a third movable electrode axis connected to the side wall,

a third spring supporting member connecting the third movable electrode axis and the substrate,

a plurality of third movable electrodes perpendicularly extending from the third movable electrode axis;

a plurality of third fixing electrodes being parallel to the third movable electrodes;

at least one third movable electrode located between two adjacent third fixing electrodes and at least one third fixing electrode located between two adjacent third movable electrodes;

the third movable electrode defining a third top surface and a third lower surface being parallel to the upper surface, a third side wall connecting the third top surface and the third lower surface;

the third fixing electrode defining a fourth top surface and a fourth lower surface being parallel to the upper surface, a fourth side wall connecting the fourth top surface and the fourth lower surface,

the third top surface being closer to the upper surface than the fourth top surface, and the third lower surface being closer to the upper surface than the fourth lower surface;

the first movable electrode being perpendicular to the third movable electrode.

2. A tri-axis accelerometer as described in claim 1, wherein

the first group of capacitance further comprises a first fixing electrode axis, and the first fixing electrode axis is disconnected to the mass, the first fixing electrode extends from the first fixing electrode axis toward the first movable electrode axis;

and

the third group of capacitance further comprises a third fixing electrode axis, and the third fixing electrode axis is disconnected to the mass, the third fixing electrode extends from the third fixing electrode axis toward the third movable electrode axis.

3. A tri-axis accelerometer as described in claim 1, wherein

the tri-axis accelerometer further comprises a second group of capacitance connected to the mass and a fourth group of capacitance connected to the mass,

the second group of capacitance has the same structure as the first group of capacitance and the second group of capacitance is symmetrical with the first group of capacitance about the mass;

the fourth group of capacitance has the same structure as the third group of capacitance and the fourth group of capacitance is symmetrical with the third group of capacitance about the mass.

4. A tri-axis accelerometer comprising

a mass, a first group of capacitance and a third group of capacitance being neighbor to the first group of capacitance,

the mass defining a top surface, a bottom surface being parallel to the upper surface and a side wall connecting the top surface and the bottom surface;

the first group of capacitance comprising

a first spring supporting member,

a first movable electrode axis defining a first end connected to the side wall, a second end connected to the first spring supporting member and a side surface connecting the first end and the second end,

a plurality of first movable electrodes perpendicularly extending from the movable electrode axis and defining a first movable electrode top surface, a first movable electrode bottom surface and a first movable electrode side wall connecting the first movable electrode top surface and the first movable electrode bottom surface;

a plurality of first stationary electrodes being parallel to the first movable electrodes and defining a first stationary electrode top surface, a first stationary electrode bottom surface and a first stationary electrode side wall connecting the first stationary electrode top surface and the first stationary electrode bottom surface;

a first stationary electrode axis being disconnected to the mass, the first stationary electrodes extending from the first fixing electrode axis toward the first movable electrode axis;

every two adjacent first movable electrodes defining a first gap therebetween and every two adjacent first stationary electrodes defining a second gap therebetween,

at least one first stationary electrode located in the first gap and at least one first movable electrode located in the second gap;

the first movable electrode top surface and the first stationary electrode top surface being not co-planar to each other, the first movable electrode top surface and the first stationary electrode bottom surface being not co-planar to each other, the first movable electrode bottom surface and the first stationary electrode bottom surface being not co-planar to each other, the first movable electrode bottom surface and the first stationary electrode top surface being not co-planar to each other;

the third group of capacitance comprising

a third spring supporting member,

a third movable electrode axis defining a third end connected to the side wall, a fourth end connected to the third spring supporting member and a side surface connecting the third end and the fourth end,

a plurality of third movable electrodes perpendicularly extending from the third movable electrode axis and defining a third movable electrode top surface, a third movable electrode bottom surface and a third movable electrode side wall connecting the third movable electrode top surface and the third movable electrode bottom surface;

a plurality of third stationary electrodes being parallel to the third movable electrodes and defining a third stationary electrode top surface, a third stationary electrode bottom surface and a third stationary electrode side wall connecting the third stationary electrode top surface and the third stationary electrode bottom surface;

a third stationary electrode axis being disconnected to the mass, the third stationary electrodes extending from the third fixing electrode axis toward the third movable electrode axis;

every two adjacent third movable electrodes defining a third gap therebetween and every two adjacent third stationary electrodes defining a fourth gap therebetween,

at least one third stationary electrode located in the third gap and at least one third movable electrode located in the fourth gap;

the third movable electrode top surface and the third stationary electrode top surface being not co-planar to each other, the third movable electrode top surface and the third stationary electrode bottom surface being not co-planar to each other, the third movable electrode bottom surface and the third stationary electrode bottom surface being not co-planar to each other, the third movable electrode bottom surface and the third stationary electrode top surface being not co-planar to each other;

an angel forming by the first movable electrode axis and the third movable electrode axis being 90 degree.

5. A tri-axis accelerometer as described in claim 4, wherein the tri-axis accelerometer further comprises

a second group of capacitance connected to the mass and a fourth group of capacitance connected to the mass,

the second group of capacitance has the same structure as the first group of capacitance and the second group of capacitance is symmetrical with the first group of capacitance about the mass;

the fourth group of capacitance has the same structure as the third group of capacitance and the fourth group of capacitance is symmetrical with the third group of capacitance about the mass.