Dual mass accelerometer with semiconductive transducer

Claim 2

An accelerometer, comprising in combination a support, two inertial bodies, structure mounting the bodies for limited swinging movement with respect to the support about respective, parallel axes mutually spaced in a plane, the centers of mass of the bodies being offset on the same side of the plane, a beam extending generally parallel to the plane and having its ends rigidly mounted on the respective bodies, and transducer means responsive to flexure stress of the beam resulting from acceleration having a component parallel to the plane and perpendicular to the axes.

Claim 3

An accelerometer as defined in claim 1, and in which the centers of mass of the two bodies are equally offset from said plane.

Claim 4

An accelerometer as defined in claim 1, and in which the centers of mass of the two bodies are equally offset in a common direction from the respective axes.

Claim 5

An accelerometer as defined in claim 1, and in which said transducer means comprise two semiconductive strain gage elements carried by the beam in longitudinally spaced relation thereon, and circuit means interconnecting the strain gage elements in a bridge network that is cumulatively responsive to flexure stress of the beam in opposite directions at the respective elements.

Claim 6

An accelerometer as defined in claim 1, and including two beams extending generally parallel to said plane and to each other with their opposite ends rigidly mounted on the respective bodies, said transducer means comprising semiconductive strain gage elements carried by the respective beams and circuit means interconnecting the elements and cumulatively responsive to similar stresses of the respective beams.

Claim 7

An accelerometer as defined in claim 1, and in which said body mounting structure is substantially inflexible in the direction parallel to said axes.

Claim 8

An accelerometer as defined in claim 1, and including also interengageable stop formations on the support and on one of the bodies for limiting said swinging movement of that body in one direction, interengageable stop formations on the support and on the other body for limiting Said swinging movement of the other body in the other direction, and laterally flexible structure interconnecting the bodies effectively at their centers of mass for maintaining essentially uniform mutual spacing thereof.

Claim 9

An accelerometer as defined in claim 1, and in which at least one of said bodies is formed with a fully enclosed internal chamber containing granular metal of a particle size to damp said body movement selectively in a frequency range that includes the effective natural frequency of vibration of the mounted bodies, and said accelerometer includes low-pass filter means for substantially eliminating from the transducer response the frequency components within said frequency range.

Claim 10

In a measuring instrument, the combination of a support, a body resiliently mounted on the support for oscillatory movement and having an effective natural frequency of vibration with respect to the support, a fully enclosed chamber in the body, containing granular metal of a particle size to damp body movement selectively in a frequency range that includes the effective natural frequency of vibration of the supported body and excludes all frequencies within a selected frequency range that is spaced below said natural frequency, transducer means for producing an electrical signal responsive to said body movement, low-pass filter means for transmitting frequencies in said selected frequency range and for substantially removing from said signal all of the frequency components within the frequency range that is effectively damped by the granular metal, and damping mechanism acting independently of the granular metal to damp the body movement substantially linearly throughout the range of frequencies transmitted by the low-pass filter means.

Claim 11

In a measuring instrument, the combination of a support, a body resiliently mounted on the support for oscillatory movement and having an effective natural frequency of vibration with respect to the support, a fully enclosed chamber in the body, containing granular metal of a particle size to damp body movement selectively in a frequency range that includes the effective natural frequency of vibration of the supported body and excludes all frequencies within a selected frequency range that is spaced below said natural frequency, transducer means for producing an electrical signal responsive to said body movement, low-pass filter means for transmitting frequencies in said selected frequency range and for substantially removing from said signal all of the frequency components within the frequency range that is effectively damped by the granular metal, and damping mechanism acting independently of the granular metal to damp the body movement substantially linearly throughout the range of frequencies transmitted by the low-pass filter means.