A specimen or in-service structural member in which strain is to be measured is fabricated as a unit which generates a signal in response to strain occurring in a given region of its surface. A film of piezoelectric material is deposited upon the surface in a manner providing a strong molecular bond between the specimen or member and the piezoelectric film. The film material is chosen from the class having a 6 mm type crystal lattice structure and is formed as a crystalline deposit with the c-ax...

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...

Strain mechanism for bandmill using deadweight lever mechanism in which undesirable effects of inertia of counterweight and friction at knife edges are reduced. Rolling diaphragm air cylinder is used in one of three positions. In first position cylinder extends between arbor carrier arm and plunger tube and supplies portion of saw strain permitting lighter counterweight. In second position it extends between counterweight arm and plunger tube and eliminates counterweights. In third position coun...

Strain gauge transducer apparatus including circuitry for balancing current through a pair of strain sensitive semiconductor resistors is disclosed. A current source supplies constant electric current to a voltage divider and a first strain sensitive resistor which are connected to noninverting and inverting input terminals respectively of an operational amplifier. A second strain sensitive resistor is connected between the output and inverting input terminals of the amplifier to provide a feedb...

This invention relates to an apparatus for stretching a textile material such that the magnitude of the strain at all points is equal in all directions in the plane of the specimen. The embodiment disclosed is an expandable circular pin frame. The pins mounted in puley are uniformly displaced radially outward and impart uniform radial strain without the edge effects associated with similar apparatus employing nonexpanding fastening mechanisms.

A simple inexpensive underwater strain sensor which can monitor the strain, nd parameters which are derived from the strain, of a sonar transducer of suitable geometry. Such a transducer is a radially oscillating, free-flooded, magnetostrictive ring transducer. The ring is assumed to be uniformly round and the circumferential strain in the lowest order purely radial mode is u/a where u is the radial displacement from equilibrium position of any point on the mean radius of the ring and a is the m...

A writing instrument is provided which generates electrical signals indicative of the force applied and the direction of motion taken by the writing instrument as one is writing with it. The writing instrument uses strain gauges for providing these signals.

An electrical connector assembly incorporating means for limiting cable tension to a predetermined value and precluding thereby mechanical failure of the cable.

A strain gage assembly has a pair of mounting collars that are adapted to be attached to an object under stress such as a corrosion resistant glass container for volatile material. A rigid member is cantilevered from one of the mounting collars to extend towards the other mounting collar. A resilient metal strip is supported and compressed between the cantilevered member and the other mounting collar. A strain measuring device is mounted on the metal strip. An adjustable stud member can be mount...

A strain gauge or a bridge comprising four strain gauges is arranged on a support such that the strain gauge(s) is (are) situated in a neutral zone. The support is secured to the object to be measured on both ends, preferably by means of screws. Between the end portions which are screwed down and the central portion accommodating the strain gauges, the support has a zone of low bending rigidity. The support can be very readily manufactured from a strip of material whose longitudinal sides are fl...