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:
Jun. 03, 1980
Filed:
Sep. 02, 1977
Joseph R Harkness, Germantown, WI (US);
Robert K Mitchell, Brookfield, WI (US);
Briggs & Stratton Corporation, Wauwatosa, WI (US);
Abstract
A completely enclosed combination clutch and brake mechanism permanently mounted at the bottom of a vertical shaft internal combustion engine of the type used to power rotary lawn mowers, is interposed between the crankshaft of the engine and a coaxial blade shaft projecting down from the bottom of the enclosed clutch and brake mechanism to have the cutting blade of the mower fixed thereto. A rotatable driving member fixed to the engine crankshaft and a rotatable driven member fixed to the blade shaft are drivingly coupled by radially outwardly movable clutch elements carried by the driven member and frictionally engaged with a radially inwardly facing circular surface on the driving member. Such frictional engagement results from the application to the clutch elements of both spring force and centrifugal force. The spring-force-produced frictional engagement effects transmission of rotation to the driven member from stand still to the speed at which the centrifugal-force-produced frictional engagement is capable of transmitting full engine torque to the blade shaft, but is incapable--due to slippage--of stopping the engine when the brake is applied, in which event rotation of the driven member is rapidly decelerated to zero.