Itt Industries, Inc.

International Standard Electric Corporation

International Standard Electric Company

Robert J Hodges

Thomas M Jackson

John C Greenwood

Aubrey M Crick

Stephen L Amphlett

Charles E Rogers

Robert Sheppard

A contactless electrical switch includes a switch element comprising a piezo-resistive transducer (25). Coded toothed cams (16) operated via a shaft (14) deflect the transducer (25) causing corresponding changes in stress and hence resistance. The output of the transducer is amplified and fed to logic circuitry which determines a corresponding current path.

Switch device

In a push-button switch, the switch element is a cantilever (2) of thin silicon strain gauge material with a small magnet (1), e.g. of samarium cobalt alloy at its free end. Adjacent to the free end there is an annular magnet (3), e.g. of plastics material impregnated with samarium cobalt alloy, on the push rod (4) of the switch. The annular magnet (3) is so poled that movement of the rod (4) causes, due to magnetic forces, the deflection of the silicon strain gauge to give an electrical output. The return force, plus collapse action, is provided by a soft iron collar (5) on the switch structure.

Push-button switch

A capsule for use as a temperature responsive element in a temperature sensitive electrical switch. The capsule is provided in a transistor mounting can configuration to facilitate printed circuit board mounting. The capsule contains a fluid and a concave disc. At a predetermined temperature, the disc snaps-over into a convex configuration. Movement of the disc is detected to provide an output signal which is temperature responsive.

Temperature sensitive capsules

An electrical snap-action switch has as its moving member a strip (15) of a springy metal with which there is integrally formed a contact-carrying arm (18). This strip is held bowed into a C shape in a metal carrier (10) with a concave inner face (11) near which the strip lies when in one position. The operating member of the switch is a rocker (23) of an insulating material which rocks on a convex 'bump' (24) on the carrier so that it has an inwardly extending pillar (24) with two studs one on each side of the strip (15). Hence operation of the rocker snaps the strip between its two positions, with corresponding movement of the contact carrying arm.

Snap-action switch

A snap-action switch unit uses as its movable element a spring strip (23) mounted in a frame (20) such that the strip is bowed. A rod or the like (22) across the strip at its middle constrains the strip so that one half is bowed away from a flat surface (21) while the other half is adjacent to and roughly parallel with the flat surface.

Switch unit

An electrical switch contact member consists of a resilient electrically conductive domed diaphragm of a predetermined shape. The diaphragm includes a frusto-conical region linking a central region of the diaphragm with a peripheral region. The frusto-conical region includes an inwardly turned or bent transition portion at its smaller end, and an outwardly turned transition portion at its larger end, and is dimensioned to function as a Belleville spring. The diaphragm may also comprise a plurality of co-axial similarly oriented frusto-conical regions each of which is inwardly turned at its smaller end, outwardly at its larger end, and which is also dimensioned to function as a Belleville spring.

Switches

A ferrule terminated optical fiber in which the fiber is held only approximately on the axis of the ferrule on the sides of which flat reference surfaces are subsequently machined. Machining is performed to a predetermined distance from the center of a fiber core, the position of which is revealed by launching light into the fiber from the other end. Providing the reference surfaces as a last manufacturing step avoids the problems of cumulative errors which arise from assembling parts having dimensional tolerances, together with the error resulting from distortion liable to occur during the setting of the adhesive holding a fiber in a ferrule.

Method of making optical fiber terminations

Optical fibers that have had the plastic coatings stripped from their ends, or ferrule terminated optical fibers or bundles, are connected in aligned butting relationship by close-wound helical strip springs.

Growing community of inventors

Cheshunt, United Kingdom

Robert J Hodges