Force sensor and structure body used therein

A force sensor which detects at least force Fz in a direction of a Z-axis and moment My around a Y-axis, of force in respective directions of each coordinate axis and moment around each coordinate axis in an XYZ three-dimensional orthogonal coordinate system, the force sensor comprising:

• a basic structure body (1000) which includes a force receiving body (100) arranged on the Z-axis when the coordinate system is defined so that the Z-axis is a perpendicular axis, a supporting body (200) which is arranged below the force receiving body, and a deformation body (300) which connects the force receiving body with the supporting body to yield at least partially elastic deformation by exertion of force or moment;
• detection elements (C1 to C4) which detect deformation or displacement of the deformation body or displacement of the force receiving body or the supporting body;
• and
• a detection circuit (900) which outputs electric signals indicating force Fz in the direction of the Z-axis and moment My around the Y-axis which have been exerted on one of the force receiving body and the supporting body in a state that loads are applied to the other on the basis of detection results of the detection elements;
• wherein
• the deformation body (300) includes an elastically deformed portion (310) which is connected at a predetermined site to the force receiving body (100) to yield elastic deformation, a first base portion (320) and a second base portion (330) fixing a predetermined site of the elastically deformed portion to the supporting body (200),
• when the basic structure body (1000) is cut along an XZ plane or a plane parallel to the XZ plane and when a geometric figure appearing on a cross section of the force receiving body is referred to as a force receiving body figure (100f), a geometric figure appearing on a cross section of the supporting body is referred to as a supporting body figure (200f) and a geometric figure appearing on a cross section of the deformation body is referred to as a deformation body figure (300f), the deformation body figure includes an elastically deformed portion figure (310f) which is a cross section of the elastically deformed portion (310), a first base portion figure (320f) which is a cross section of the first base portion (320) and a second base portion figure (330f) which is a cross section of the second base portion (330),
• the elastically deformed portion figure (310f) is arranged along a predetermined connection channel (R1) which connects a first force receiving point (P1) with a second force receiving point (P2) which are defined on a contour of the force receiving body figure (100f), the elastically deformed portion figure couples the first force receiving point (P1) to the second force receiving point (P2),
• the first base portion figure (320f) is connected to the elastically deformed portion FIG. (310f) in a vicinity of a first relay point (m1) defined on the connection channel (R1), and the second base portion figure (330f) is connected to the elastically deformed portion figure (310f) in a vicinity of a second relay point (m2) defined on the connection channel (R1),
• the elastically deformed portion (310) couples the first force receiving point (P1) to the second force receiving point (P2), the first base portion (320) couples the vicinity of the first relay point (m1) at the elastically deformed portion (310) to a first supporting point (Q1) defined on the supporting body (200), and the second base portion (330) couples the vicinity of the second relay point (m2) at the elastically deformed portion (310) to a second supporting point (Q2) defined on the supporting body (200),
• the first force receiving point (P1) is arranged at a position having a negative coordinate value of an X-axis and the second force receiving point (P2) is arranged at a positive coordinate value of the X-axis, and
• when force Fz is exerted on the force receiving body (100) in a state that the supporting body (200) is fixed and when moment My is exerted on the force receiving body (100) in a state that the supporting body (200) is fixed, the vicinity of the first relay point (m1) at the elastically deformed portion (310) sways in the direction of the X-axis in relation to the first base portion (320), with a connection point (m1′) with the first base portion (320) given as a supporting point, and the vicinity of the second relay point (m2) at the elastically deformed portion (310) sways in the direction of the X-axis in relation to the second base portion (330), with a connection point with the second base portion (330) given as a supporting point.