Six-axis sensor

• US 7,360,456 B2
• Filed: 06/16/2004
• Issued: 04/22/2008
• Est. Priority Date: 06/17/2003
• Status: Expired due to Fees

• Current Assignee: Nippon Liniax Co., Ltd. (Nichicon Corporation)
• Original Assignee: Nitta Corporation
• Inventors: Morimoto, Hideo
• Primary Examiner(s): Lefkowitz; Edward
• Assistant Examiner(s): DUNLAP, JONATHAN M
• Application Number:
  US10/560,995
• Publication Number:
  US 20060174718A1
• Time in Patent Office: 1,406 Days
• Field of Search: 738/620.44
• US Class Current: 73/862.044
• CPC Class Codes: G01L 1/2225 the direction being perpendicular to the central axis
• CPC Class Codes: G01L 1/2231 the supports being disc- or ring-shaped, adapted for measuring a force along a single direction
• 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

A sensor strain causer can be made into a simple shape, and the attachment work for strain gauges is made easy. In a multiaxial sensor 1 for measuring one or more of multiaxial force, moment, acceleration, and angular acceleration, externally applied, a plurality of strain gauges R11 to R48 disposed on one plane are provided. Thereby, because the time for the attachment work for the strain gauges R11 to R48 can be shortened, the mass productivity can be improved and the cost can be reduced.

Claims

1. A 6-axis sensor for measuring 6-axis forces and moments or 6-axis accelerations and angular accelerations, externally applied, characterized by comprising:

a plurality of strain gauges disposed on one plane;

a plurality of first diaphragms to which the plurality of strain gauges are attached;

a first member comprising one of the plurality of first diaphragms;

a second member comprising a second diaphragm opposed to the one of the plurality of first diaphragms and provided with a plurality of strain gauges disposed on one plane; and

a connecting shaft connecting the opposed first and second diaphragms;

wherein the plurality of first diaphragms are arranged around a central point of the plane at regular angular intervals and at the same distance from the central point;

6-axis forces and moments applied between the first and second members are measured;

the strain gauges of the first member and the strain gauges of the second member are disposed symmetrically with respect to a barycentric point of the 6-axis sensor; and

either outputs of the strain gauges of the first member and the strain gauges of the second member are adopted if the other ouputs are out of a predetermined range.

2. The 6-axis sensor according to claim 1, characterized in that the angular interval in 90 degrees.

3. The 6-axis sensor according to claim 1, characterized in that the diaphragms are disposed in positive and negative direction on X and Y axes with an origin being defined at the central point.

4. The 6-axis sensor according to claim 1, characterized in that the angular interval is 120 degrees.

5. The 6-axis sensor according to claim 1, characterized in that a thin portion of each of the plurality of first diaphragms is annular and provided with eight strain gauges, and

the strain gauges are disposed at outer and inner edge portions of each of the plurality of first diaphragms on a line extending between a central point of each of the plurality of first diaphragms and the central point of the plane, and at outer and inner edge portions of each of the plurality of first diaphragms on a line perpendicular to the former line at the central point of each of the plurality of first diaphragms.

6. The 6-axis sensor according to claim 1, characterized in that the 6-axis sensor further comprises an operative body provided on a central portion of one or more of the plurality of first diaphragms, and

6-axis accelerations and angular accelerations applied to the 6-axis sensor are measured.

7. The 6-axis sensor according to claim 1, characterized in that each of the strain gauges is made of a piezoresistance element.

8. The 6-axis sensor according to claim 1, characterized in that each of the strain gauges is made of a thin film of chromium oxide formed on an insulating film.

9. A 6-axis sensor for measuring 6-axis forces and moments or 6-axis accelerations and angular accelerations, externally applied, the 6-axis sensor comprising:

a plurality of strain gauges disposed on one plane;

a plurality of first diaphragms to which the plurality of strain gauges are attached;

wherein only one of the plurality of first diaphragms is disposed on the plane;

a first member comprising one of the plurality of first diaphragms;

a second member comprising a second diaphragm provided with a plurality of strain gauges disposed on one plane; and

operative bodies connecting the first and second diaphragms,

wherein the first and second members are disposed so that a central point of the first diaphragm of the first member is opposed to a central point of the second diaphragm of the second member,

wherein the operative bodies connects the first and second diaphragms at positions arranged around the central points of the first and second diaphragms at regular angular intervals and at the same distance from the central points, and 6-axis forces and moments applied between the first and second members are measured,

wherein the strain gauges of the first member and the strain gauges of the second member are disposed symmetrically with respect to a barycentric point of the 6-axis sensor, and

wherein either outputs of the strain gauges of the first member and the strain gauges of the second member are adopted if the other outputs are out of a predetermined range.

10. The 6-axis sensor according to claim 9, characterized in that the angular interval is 90 degrees.

11. The 6-axis sensor according to claim 9, characterized in tat the operative bodies are disposed in positive and negative directions on X and Y axes with an origin being defined at the central point of the first diaphragm.

12. The 6-axis sensor according to claim 9, characterized in that the angular interval is 120 degrees.

13. The 6-axis sensor according to claim 9, characterized in that the strain gauges are disposed:

at edge portions of the operative bodies on a line extending between a central point of a portion on the plane corresponding to the operative bodies, and the central point of the first diaphragm;

at edge portions of the operative bodies on a line perpendicular to the former line at the central point of the portion on the plane corresponding to the operative bodies; and

at either of edge portions of the operative bodies and edge portions of the first diaphragm, at positions arranged around the central point of the first diaphragm at regular angular intervals and at the same distance from the central point.

14. The 6-axis sensor according to claim 9, characterized in that each of the strain gauges is made of a piezoresistance element.

15. The 6-axis sensor according to claim 9, characterized in that each of the strain gauges is made of a thin film of chromium oxide formed on an insulating film.