A recording instrument is disclosed for measuring and recording changes in linear distance between two predetermined points. The instrument is comprised of a recording tape and a scribing means for marking the changes in linear distance on the tape. The scribing means moves in a direction which is transverse to the longitudinal axis of the tape. The instrument includes a tape housing means which accommodates the tape so that the tape is free to move along its longitudinal axis but is substantial...

A strain transducer for use in the measurement of static or quasi-static high strain levels at stress concentration points in holes in flat plates. Cantilever springs constructed by machining the material to appropriate flexibility, permit self-alinement, and constant contact with the test specimen. Used in conjunction with a strain gage or other transducer, it enables testing far beyond the strain gage's normal limits for high strains and number of load cycles.

A bandmill in which a bandsaw extending around two bandwheels is subjected to strain by causing the two wheels to be spread apart by a jacking system incorporating an air spring. The air spring comprises a bellows unit or a rolling diaphragm air cylinder unit and may act through a linkage or directly between the frame of the bandmill and the journal of one of the wheels movable in the frame.

A device for measuring the biaxial strain of a test specimen is provided, utilizing a coaxial resonant cavity, made to resonate in at least two different modes by electromagnetic energy supplied to the cavity. A first mode is dependent upon the diametric dimensions of the cavity and a second mode is dependent upon the axial and diametric dimensions of the cavity. The cavity is formed of a hollow, sensor body whose electrically conductive inner walls, one of which is movable, function as the oute...

A strain-deformable wire resistance strain gage is cemented to a ship's propeller or turbine blade, and covered with a water vapor curable silicone plastic polymer protective layer in an unset state; a metal screen overlay is tack-welded with the aid of sheet metal strips through the unset silicone plastic to the propeller or turbine blade, after which the protective layer is air cured, forming a seal around the welds and the gage.

A strain gage transducer suitable for use in the measurement of forces along three orthogonal axes and moments about two of these axes. The transducer includes a substantially square plate. The center of the square plate is located at the intersection of two imaginary diagonal lines drawn between oopposite corners of the square plate. The plater has four openings equidistantly located from the center of the square plate, and each of the openings is located between the center and a corner of the ...

A strain gauge system incorporating a plurality of pairs of strain gauges, each of which is mounted on an axle or the like, said strain gauges being connected in a plurality of bridge circuits, each having an independent power supply, with the bridge circuits being connected in series to produce an output voltage which is proportional to the total load. A manually operable voltage source is connected with the output of the bridge circuits, and an operational amplifier is connected with the volta...

A strain gage transducer for use in a radially confined space has a support portion including a base and outer wall structure extending from the perimeter of the base, a columnar member secured to the base internally of the outer wall structure and extending therebeyond, providing a contact end, and strain gage elements secured to the columnar member between the base and the contact end.

Transducers of the resistance wire type are described, wherein strained resistance wires are adapted to function both as a sensor and load bearing member. These transducers comprise a pair of spaced apart load carrying or attaching devices which are connected by a plurality of lengths of resistance wire or filament, such as a coil, belt or rope of wire construction, in which the individual lengths of wire are mechanically parallel but are preferably connected in series electrically so as to form...

The present invention defines an improved strain gauge and a method of using an electromagnetic acoustic transducer (EMAT) for monitoring stress and strain in an underlying workpiece. The gauge is provided with positioning pins for fixing the registration of the EMAT relative to the workpiece. The gauge is provided with a friction reducing means, such as a bearing or a wheel assembly, to minimize EMAT bottom contact surface area and thus unwanted frictional influences caused by deformation of th...