Multiaxial sensor

• US 7,500,406 B2
• Filed: 06/21/2004
• Issued: 03/10/2009
• Est. Priority Date: 09/30/2003
• Status: Expired due to Fees

• Current Assignee: Nitta Corporation
• Original Assignee: Nitta Corporation
• Inventors: Morimoto, Hideo
• Primary Examiner(s): Lefkowitz; Edward
• Assistant Examiner(s): ROY, PUNAM P
• Application Number:
  US10/574,253
• Publication Number:
  US 20070000335A1
• Time in Patent Office: 1,723 Days
• Field of Search: 738/620.41, 738/620.42, 738/620.43, 738/620.44, 738/620.45, 735/143.3, 735/143.4, 438/53, 257/417, 257/419
• US Class Current: 73/862.044
• CPC Class Codes: G01L 5/162 of piezoresistors
• CPC Class Codes: G01L 5/1627 of strain gauges using piezoresistors G01L5/162
• 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

Abstract

Cost is reduced by simplifying the wiring while reducing power consumption. A multi-axis sensor unit (10) for measuring any one or more of multi-axis force, moment, acceleration and angular acceleration applied externally, comprising eight strain gauges (R11-R24) arranged on one plane, and one bridge circuit (11) formed by interlinking the strain gauges (R11-R24). As compared with a conventional multi-axis sensor unit, power consumption is reduced by decreasing the number of bridge circuits (11) and the strain gauges (R11-R24), and production cost is lowered by simplifying the wiring.

Claims

1. A multiaxial sensor having a plurality of multiaxial sensor units for measuring one or more of two or more-axial force, moment, acceleration, and angular acceleration, externally applied, the plurality of multiaxial sensor units being disposed on a same plane and disposed around a center point of the multiaxial sensor at 90 degree intervals at the same distance from the center point, each of the multiaxial sensor units comprising:

eight strain gauges disposed on a single plane;

one bridge circuit constructed by connecting the strain gauges; and

a strain generation body comprising a force receiving portion provided at a center, a fixed portion provided on an outer circumference, and an annular diaphragm portion connecting the force receiving portion and the fixed portion to each other;

wherein the strain gauges being disposed at four positions on outer and inner edges of the diaphragm on a line perpendicular to a center line of the diaphragm, and at four positions on the outer and inner edges of the diaphragm on a line perpendicular to the line perpendicular to the center line of the diaphragm; and

each of the strain gauges is a piezoresistive element or a strain gauge formed by sputtering.

2. The multiaxial sensor according to claim 1, wherein the multiaxial sensor units are disposed in positive and negative directions on X- and Y-axes with an origin being set at the center point.

3. The multiaxial sensor according to claim 1, wherein the eight strain gauges of each multiaxial sensor unit are disposed at four positions on outer and inner edges of the diaphragm on a line extending through a center point of the multiaxial sensor and a center point of each multiaxial sensor unit;

and at four positions on the outer and inner edges of the diaphragm on a line perpendicular to the former line at the center point of the said multiaxial sensor unit.

4. The multiaxial sensor according to claim 1, wherein the sensor comprises a first member comprising the multiaxial sensor units each comprising the strain gauges;

and a second member comprising strain generation bodies opposed to the multiaxial sensor units and comprising no strain gauges, and opposed force receiving portions of strain generation bodies are connected to each other, and multiaxial forces and moments applied between the first and second members are measured.

5. A multiaxial sensor having a plurality of multiaxial sensor units for measuring one or more of three or more-axial force, moment, acceleration, and angular acceleration, externally applied,

the plurality of multiaxial sensor units being disposed on a same plane and disposed around a center point of the multiaxial sensor at regular angular intervals at the same distance from the center point,

each of the multiaxial sensor units comprising:

eight strain gauges disposed on a single plane;

two bridge circuits constructed by connecting the strain gauges; and

a strain generation body comprising a force receiving portion provided at a center, a fixed portion provided on an outer circumference, and an auntilar diaphragm portion connecting the force receiving portion and the fixed portion to each other;

the strain gauges being disposed at four positions on outer and inner edges of the diaphragm on a line perpendicular to a center line of the diaphragm, and at four positions on the outer and inner edges of the diaphragm on a line perpendicular to the line perpendicular to the center line of the diaphragm;

wherein each of the strain gauges is a piezoresistive element or a strain gauge formed by sputtering.