Means for adjusting the sensitivity of a crystal detector
AssigneeWestern Geophysical Company of America
InventorRobert C. Shopland
Life of this patent
Estimating the term…
Abstract
A twin-transducer seismic detector includes a hollow housing closed at each end by a diaphragm-type transducer. A deformable retaining member is pressed against the perimeter of each transducer. An adjustable force is applied to at least one of the deformable members to cause the member to flatten against the transducer. As the deformable member becomes flattened, it reduces the effective area of the transducer and hence alters its compliance and sensitivity. The applied force is adjusted so as to match the sensitivity of one transducer to that of the other transducer.
Claims6
In a detector of the type including a housing having an internal chamber that is closed at each end by a diaphragm-type transducer, means for matching the sensitivity of said transducers, comprising:
- a shoulder at each of said housing for receiving each said transducer;
- resilient deformable members contacting said transducers externally of said chamber;
- means for urging said resilient deformable members against said transducers;
- and
- means for applying an adjustable deforming force to at least one of said deformable members through said urging means to alter the compliance of the corresponding transducer until its sensitivity matches the sensitivity of the other transducer.
In an accelerometer of the type including a housing closed at each end by a diaphragm-type transducer to form a chamber for containing a volume of a liquid inertia mass internally of said housing between said transducers, the improvement comprising:
- resilient deformable ring members contacting said transducers around the perimeters thereof, externally of said chamber;
- bezel rings for urging said deformable ring members against said transducers;
- threaded, rotatable end caps for pressing said bezel rings against said deformable ring members to apply an adjustable deforming force to said ring members so that they spread out to alter the compliance of said transducers.
Dependencies are inferred from the claim text.