Angular velocity sensors

Claim 2

An angular rate sensor including: a. a housing; b. a first proof mass element carried by the said housing; c. a second proof mass element carried by the said housing; d. driving means for driving the first and second proof mass elements so that each experiences cyclically repetitive rectilinear movement along an axis common to both proof mass elements and the instantaneous movements of the two mass elements relative to the housing being in opposite directions along that axis so as to produce dynamic balance therebetween; e. first and second piezoelectric devices acting in the compression mode and acting respectively on opposite ends of the first proof mass element to cause its said repetitive movement; f. third and fourth piezoelectric devices acting in the compression mode and acting respectively on opposite ends of the second proof mass element to cause its said repetitive movement; and g. further piezoelectric devices arranged to act as sensor means; said further piezoelectric devices being connected respectively to opposite ends of an assembly consisting of the said proof masses and said first through fourth piezoelectric devices and said further piezoelectric devices being arranged to act in the shear mode and to provide an electrical output indicative of Coriolis forces acting on the proof mass elements in a direction transverse to their said cyclically repetitive movements.

Claim 3

An angular rate sensor according to claim 1, in which means arranged to interpret information from the said sensor means also provides information as to angular rate of the housing.

Claim 4

An angular rate sensor according to claim 1, in which means arranged to interpret information from said sensor means also provides information as to linear acceleration of the housing.

Claim 5

An angular rate sensor according to claim 1, in which second sensor means are arranged to provide a second output indicative of Coriolis forces on the said mass elements when the sensor housing is subjected to an angular velocity about a second predetermined axis also normal to the said common axis; the arrangement of the sensor means being such that the operation of the driving means in driving the proof mass elements produces substantially no net output from the sensor means in the absence of the production of Coriolis forces on the proof mass elements.

Claim 6

An angular rate sensor according to claim 1, and in which: a. a first driving means drives the first proof mass element; b. a second driving means drives the second proof mass element independently of the first proof mass element; c. adjustment means permit adjustment of the driving means to produce a desired dynamic balance between the first and second proof mass elements.

Claim 7

An angular rate sensor including: a. a housing; b. a first proof mass element carried by the said housing; c. a second proof mass element carried by the said housing; d. driving means for driving the first and second proof mass elements so that each experiences cyclically repetitive rectilinear movement along an axis common to both proof mass elements and the instantaneous movements of the two mass elements relative to the housing being in opposite directions along that axis so as to produce dynamic balance therebetween; e. first and second piezoelectric devices acting in the compression mode and acting respectively on opposite ends of the first proof mass element to cause its sand repetitive movement; f. third and fourth piezoelectric devices acting in the compression mode and acting respectively on opposite ends of the second proof mass element to cause its said repetive movement; and g. further piezoelectric devices arranged to act as sensor means; said further piezoelectric devices being connected respectively to opposite ends of an assembly consisting of the said proof masses and said first through fourth piezoelectric devices and said further piezoelectric devices being arrangEd to act in the compression mode and to provide an electrical output indicative of Coriolis forces acting on the proof mass elements in a direction transverse to their said cyclically repetitive movements.

Claim 8

An angular rate sensor including: a. a housing; b. a first proof mass element carried by the said housing; c. a second proof mass element carried by the said housing; d. driving means for driving the first and second proof mass elements so that each experiences cyclically repetitive rectilinear movement along an axis common to both proof mass elements and the instantaneous movements of the two mass elements relative to the housing being in opposite directions along that axis so as to produce dynamic balance therebetween; e. first and second piezoelectric devices acting in the compression mode and acting respectively on opposite ends of the first proof mass element to cause its sand repetitive movement; f. third and fourth piezoelectric devices acting in the compression mode and acting respectively on opposite ends of the second proof mass element to cause its said repetive movement; and g. further piezoelectric devices arranged to act as sensor means; said further piezoelectric devices being connected respectively to opposite ends of an assembly consisting of the said proof masses and said first through fourth piezoelectric devices and said further piezoelectric devices being arrangEd to act in the compression mode and to provide an electrical output indicative of Coriolis forces acting on the proof mass elements in a direction transverse to their said cyclically repetitive movements.

Claim 9

An angular rate sensor according to claim 6, in which means arranged to interpret information from the said sensor means also provides information as to angular rate of the housing.

Claim 10

An angular rate sensor according to claim 6, in which means arranged to interpret information from said sensor means also provides information as to linear acceleration of the housing.

Claim 11

An angular rate sensor according to claim 6, and in which: a. a first driving means drives the first proof mass element; b. a second driving means drives the second proof mass element independently of the first proof mass element; and c. adjustment means permit adjustment of the driving means to produce a desired dynamic balance between the first and second proof mass elements.

Claim 12

An angular rate sensor according to claim 6, in which second sensor means are arranged to provide a second output indicative of Coriolis forces on the said mass elements when the sensor housing is subjected to an angular velocity about a second predetermined axis also normal to the said common axis; the arrangement of the sensor means being such that the operation of the driving means in driving the proof mass elements produces substantially no net output from the sensor means in the absence of the production of Coriolis forces on the proof mass elements.

Claim 13

An angular rate sensor including: a. a housing; b. a first proof mass element carried by the said housing; c. a second proof mass element carried by the said housing; d. driving means for driving the first and second proof mass elements so that each experiences cyclically repetitive rectilinear movement along an axis common to both proof mass elements and the instantaneous movements of the two mass elements relative to the housing being in opposite directions along that axis so as to produce dynamic balance therebetween; e. first and second piezoelectric devices acting in the compression mode and acting respectively on opposite ends of the first proof mass element to cause its said repetitive movement; f. third and fourth piezoelectric devices acting in the compression mode and acting respectively on opposite ends of the second proof mass element to cause its said repetitive movement; g. further piezoelectric devices arranged to act as sensor means; and h. a mechanical drive connecting the proof mass elements to the said further piezoelectric devices and providing a mechanical advantage so that the force exerted on the piezoelectric devices is greater than the force exerted on the drive by the proof mass elements; said further piezoelectric devices thus providing an electrical output indicative of Coriolis forces acting on the proof mass elements in a direction transverse to their cyclically repetitive movements.

Claim 14

An angular rate sensor including: a. a housing; b. a first proof mass element carried by the said housing; c. a second proof mass element carried by the said housing; d. driving means for driving the first and second proof mass elements so that each experiences cyclically repetitive rectilinear movement along an axis common to both proof mass elements and the instantaneous movements of the two mass elements relative to the housing being in opposite directions along that axis so as to produce dynamic balance therebetween; e. first and second piezoelectric devices acting in the compression mode and acting respectively on opposite ends of the first proof mass element to cause its said repetitive movement; f. third and fourth piezoelectric devices acting in the compression mode and acting respectively on opposite ends of the second proof mass element to cause its said repetitive movement; g. further piezoelectric devices arranged to act as sensor means; and h. a mechanical drive connecting the proof mass elements to the said further piezoelectric devices and providing a mechanical advantage so that the force exerted on the piezoelectric devices is greater than the force exerted on the drive by the proof mass elements; said further piezoelectric devices thus providing an electrical output indicative of Coriolis forces acting on the proof mass elements in a direction transverse to their cyclically repetitive movements.

Claim 15

An angular rate sensor according to claim 11, in which means arranged to interpret information from the said sensor means also provides information as to angular rate of the housing.

Claim 16

An angular rate sensor according to claim 11, in which means arranged to interpret information from said sensor means also provides information as to linear acceleration of the housing.

Claim 17

An angular rate sensor according to claim 11, and in which: a. a first driving means drives the first proof mass element; b. a second driving means drives the second proof mass element independently of the first proof mass element; and c. adjustment means permit adjustment of the driving means to produce a desired dynamic balance between the first and second proof mass elements.

Claim 18

An angular rate sensor according to claim 11, in which second sensor means are arranged to provide a second output indicative of Coriolis forces on the said mass elements when the sensor housing is subjecteD to an angular velocity about a second predetermined axis also normal to the said common axis; the arrangement of the sensor means being such that the operation of the driving means in driving the proof mass elements produces substantially no net output from the sensor means in the absence of the production of Coriolis forces on the proof mass elements.