Air vane governor for internal combustion engine

Claim 1

An internal combustion engine comprising a carburetor having a throat, a pivotal throttle member disposed in said throat and pivotable between an open position and a fluid flow restricting position, a movable air vane including a body comprising an annular wall extending axially from said body and having an inner surface, a rotatable shaft carrying said throttle member and connected to said air vane for moving said throttle member in response to movement of said air vane, means for impelling air against said air vane to move said air vane and urge said throttle member toward a flow restricting position in response to engine rotation, a torsion spring encircling said shaft, having a first end connected to said shaft for biasing said throttle member toward the open position, and having a second end, and adjustment means connected to said spring for adjusting the biasing force of said spring on said throttle member, said adjustment means including a control member connected to said second end of said spring and mounted remotely from said shaft for movement which is solely reciprocatory in a direction transversely of the rotational axis of said shaft between a first spring force level position and a second spring force level position, a collar surrounding said shaft and connected to said first end of said spring, and interlocking means on said air vane and on said collar for effecting common rotation of said air vane and said collar and for releasably permitting rotation of said collar relative to said air vane so as to adjust the biasing force of said spring on said throttle member, said interlocking means including a plurality of circumferentially spaced indentations on said inner surface of said wall, a detent element on said collar for lockingly engaging said indentations, and biasing means for biasing said detent element into releasable locking engagement with said indentations.