Ranco Inc.

Ranco Inc. of Delaware

Robert F Purssell

Guglielmo Rossi

Alastair K Stevenson

Albert L Fowler

David M Walker

Alan G Henderson

Alfred J Woollard

Avtar S Bhabra

Alan Pelczyk

A trip-free mechanism for resetting an on-off unit, such as a thermostat (1), breakable by the tripping of an actuator element (3) from a first condition to a second condition comprises a resetting button (9) engageable to apply a resetting force to the actuator element (3) to reset the latter in its first condition, and a restraining lever (10) acted upon by the resetting button (9) when it applies the resetting force to the actuator element (3) to maintain the unit in its broken condition until the button (9) is disengaged upon resetting of the actuator element.

Trip-free resetting mechanism for an on-off unit

A displacement-measuring transducer has a laminar member displaceable, for example under control of a vacuum actuator, within a housing containing respective pairs of coils spaced part in the displacement direction of the laminar member, which is provided with two apertures spaced apart in the said direction, such that the coupling between the coils of each pair is dependent upon the position of said apertures and, therefore, on the displacement of the laminar member.

Displacement measuring transducer

A snap action switch blade has a pair of resiliently flexible arms projecting cantilever fashion from a support and drawn together to prestress the blade for snap action, the blade being anchored to the support by two lugs projecting in the opposite direction to the arms and an electrical contact being mounted off-axis near one of the arms of the blade.

Snap action switches

A snap action switch blade has a basic `Q` shape with two arms interconnected and drawn together by a bridge portion, which may be integral with the arms, to form a deformed loop capable of snap movement between two configurations, with respective tongues projecting into and out of the loop to afford anchoring and/or actuating points for the blade.

Growing community of inventors

Plymouth, United Kingdom

Robert F Purssell