Force detection device

• US 7,121,147 B2
• Filed: 11/12/2004
• Issued: 10/17/2006
• Est. Priority Date: 03/31/2003
• Status: Expired due to Term

• Current Assignee: WACOH-TECH Inc.
• Original Assignee: Wacoh Company
• Inventors: Okada, Kazuhiro
• Primary Examiner(s): NOORI, MAX H
• Application Number:
  US10/988,359
• Publication Number:
  US 20050092096A1
• Time in Patent Office: 704 Days
• Field of Search: 737/74, 737/81, 737/88, 737/60
• US Class Current: 73/760
• CPC Class Codes: G01L 5/165 using variations in capacitance

Abstract

Forces and moments are detected in a distinguishing manner by a simple structure. A supporting member (20) is positioned below a force receiving member (10), which receives forces to be detected, and between these components, at least two columnar force transmitting members (11, 12) are connected. Connecting members having flexibility are interposed at the upper and lower ends of each of columnar force transmitting members (11, 12) so that columnar force transmitting members (11, 12) can become inclined when force receiving member (10) becomes displaced upon receiving a force. Sensors (21, 22) are positioned at the respective connection parts of columnar force transmitting members (11, 12) and supporting member (20) to detect forces that are transmitted from the respective columnar force transmitting members (11, 12) to supporting member (20). Based on the detection values of sensors (21, 22), detection processing unit 30 detects, in a distinguishing manner, forces and moments acting on force receiving member (10). When four columnar force transmitting members are used, all of forces Fx, Fy, and Fz and moments Mx, My, and Mz can be detected.

Claims

1. A force detection device comprising:

a force receiving member for receiving force to be detected;

a supporting member positioned below said force receiving member;

a force transmitting member having an upper end thereof connected to said force receiving member and a lower end thereof connected via a connecting member, having flexibility, to said supporting member;

a sensor for detecting force applied from said force transmitting member to said supporting member; and

a detection processing unit for performing a process of detecting a force or moment component acting on said force receiving member in consideration of a detection result of said sensor, wherein said flexibility of said connecting member is provided by a diaphragm.

2. The force detection device of claim 1 wherein said diaphragm comprises a thin flexible member to which said force transmitting member is connected.

3. The force detection device of claim 2 wherein said force transmitting member is connected to a central region of said diaphragm and extends perpendicularly thereto.

4. The force detection device of claim 3 wherein said diaphragm has a circumference connected to said supporting member.

5. The force detection device of claim 3 wherein said sensor is adjacent to said diaphragm on a side thereof opposite the force transmitting member.

6. The force detection device of claim 2 wherein said sensor comprises a fixed electrode secured to said supporting member and a movable electrode formed with said diaphragm.