Inertial force sensor

Abstract

An inertial force sensor includes a detector element, a supporting body supporting the detector element, and a case holding the detector element via the first supporting body. The supporting body has flexibility and has a plate shape. The detector element includes a weight, a flexible coupling portion extending along a plane and supporting the weight, a fixing portion holding the weight via the coupling portion, and a detector detecting angular velocities about at least two axes non-parallel to each other. The supporting body extends in parallel with the plane from the detector element, and bends at a bending portion in a direction away from the plane. This inertial force sensor can detect the angular velocities while preventing erroneous detection caused by external impacts and vibrations.

1 . An inertial force sensor comprising
 a detector element including:
 a first beam; 
 a second beam parallel with the first beam; 
 a third beam, a fourth beam, a fifth beam, and a sixth beam which connect between the first beam and the second beam; 
 a seventh beam connected to the fourth beam and extending in parallel with the first beam; and 
 a eighth beam connected to the fifth beam and extending in parallel with the first beam, 
   wherein a first slit is provided between the third beam and the fourth beam,   wherein a second slit is provided between the fifth beam and the sixth beam,   wherein a width of the fourth beam is smaller than a width of the first beam,   wherein a width of the fifth beam is smaller than a width of the second beam,   wherein a width of the third beam is larger than the width of the fourth beam and larger than a width of the first slit,   wherein a width of the sixth beam is larger than the width of the fifth beam and larger than a width of the second slit,   
     
     
         2 . The inertial force sensor according to  claim 1 , wherein the first slit is parallel with the second slit. 
     
     
         3 . The inertial force sensor according to  claim 2 , wherein the detector element further includes:
 a ninth beam and a tenth beam which are connected to the seventh beam and are parallel with the third beam; and   an eleventh beam and a twelfth beam which are connected to the eighth beam and are parallel with the third beam.   
     
     
         4 . The inertial force sensor according to  claim 3 , wherein each of the ninth beam, the tenth beam, the eleventh beam, and the twelfth beam has two bending portions. 
     
     
         5 . The inertial force sensor according to  claim 3 , further comprising:
 a supporting body supporting the detector element; and   a member connected to the detector element via the supporting body,   wherein the supporting body has at least two bending portions.   
     
     
         6 . The inertial force sensor according to  claim 5 , wherein the supporting body bends perpendicularly at the at least two bending portions. 
     
     
         7 . The inertial force sensor according to  claim 6 ,
 wherein the detector element is parallel with a plane, and   wherein the supporting body bends perpendicularly at the at least two bending portions viewing in a direction perpendicular to the plane.   
     
     
         8 . The inertial force sensor according to  claim 5 , wherein the supporting body is made of a material different from a material of the detector element. 
     
     
         9 . The inertial force sensor according to  claim 1 , wherein the detector element is configured to detect an angular velocity about one axis. 
     
     
         10 . The inertial force sensor according to  claim 1 , wherein the detector element is configured to detect angular velocities about two axes. 
     
     
         11 . The inertial force sensor according to  claim 1 , wherein the detector element is configured to detect angular velocities about three axes.