The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 25, 1976
Filed:
Oct. 07, 1974
Frank J Graninger, Milwaukee, WI (US);
Allen-Bradley Company, Milwaukee, WI (US);
Abstract
An electrical limit switch has a rotary camshaft provided in an operating head which is mounted upon a main switch body which houses electrical switch contacts. Rotational input motion of the camshaft is translated into a linear output motion of an actuator for operating the switch contacts. A minor return spring acts in series with a major return spring upon a flat formed in the camshaft to center the camshaft in a neutral position. The minor return spring is compressed as the camshaft is initially rotated to enable a low torque operation of the shaft until after actuation of the switch contacts, while the major return spring is compressed after switch actuation to provide a principal return force for the camshaft upon its rotary deviation from the neutral position. A spring stop element is inserted between the major and minor springs to limit compression of the minor return spring following an operation of the switch contacts.