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US 4,071,002 AGranted
Throttle and ignition advance linkage for an internal combustion engine
AssigneeBrunswick Corporation
InventorJames H. Frahm
Life of this patent
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AssigneeBrunswick Corporation
InventorJames H. Frahm
Estimating the term…
The carburetor throttle valve of an internal combustion engine is set in timed relation to a timing control coil by a T-shaped throttle control lever coupled to an external throttle operator and a timing control lever resiliently coupled to the throttle control lever. The two control levers are pivotally mounted on a common pivot pin secured to the engine block. The T-shaped throttle lever is pivotally mounted at the center of the cross-bar with a pair of throttle control cables secured to the opposite ends and to an external throttle control. The stem of the lever projects outwardly toward the carburetor valve input element. A cam member includes a slotted and clamp screw connection to one side of the stem to permit adjustment of the cam member along the length of the stem. A guide wal is coupled to the other side of the stem by a T-shaped stem and groove. The cam member has a first flat cam surface spaced from the valve pin at idle and an angular oriented second surface to provide an amplified throttle movement after a timing advance limit is reached. The timing lever extends across the cross-bar of the throttle lever with a hook end extended outwardly in laterally spaced relation to the stem. A coil spring connects the hook end to the stem portion. The opposite end of the timing lever is adjustably secured to the timing rod for positioning a firing coil of a capacitor discharge ignition system. A stop screw on the timing lever limits the advance firing position of the coil. The initial rotation of the throttle control lever rotates the timing lever means to TDC and the throttle lever to just engage the valve input. Rotation of the throttle lever for a relatively small angle then simultaneously rapidly advances the timing and slowly opens the throttle after which the timing lever engages the stop means and the throttle is advanced with fixed timing.
A throttle control apparatus having a movable throttle setting element, comprising a common pivot pin, a throttle control lever pivotally mounted on the pin and having a minimum throttle position and movable to an advanced throttle position, a timing control lever pivotally mounted on the pin, a drive means coupled to the throttle control lever for pivoting the control lever, resilient means coupling the levers for moving the timing control lever with the throttle control lever, and a lost motion coupling means connected to the throttle control lever and to the throttle setting element for moving the throttle setting element only after a selected initial movement of the throttle control lever and the timing control lever prior to movement of the throttle control lever into engagement with the throttle setting element and wherein said throttle control lever is a T-shaped member having a cross-bar and stem, said lost motion coupling means including an adjustable cam member and releasable attachment means adjustably secured to the stem of said T-shaped member and to the cam member for selective positioning along said stem, and said timing control lever extended generally parallel to the cross-bar, said resilient means coupling the one end of the timing control lever to the stem, the opposite end of the timing control lever including a pivotally mounted timing link.
A throttle control linkage for an internal combustion engine including a movable engine throttle element for adjusting the speed setting of the engine and movable between a minimum throttle position and an advanced throttle position and a movable timing control element, comprising a common pivot pin, a pivotally mounted throttle control lever pivotally mounted on said pin and having a projecting portion and having a minimum throttle idle position and rotatable throughout a selected range to an advanced throttle position for progressively increasing of the speed selection of the engine, input positioning means connected to the opposite ends of the throttle control lever for pivoting thereof between said idle and advance positions, a timing control lever pivotally mounted on said pin in stacked relation to the throttle control lever, a throttle control member, an adjustable attachment means connecting said throttle control member to said projecting portion, a second control member connected to the throttle element and located in the path of said first member, said members being disengaged in the idle position of the throttle control lever and producing movement of only the throttle control lever and the first member during the initial movement of the throttle control lever and then engaging said first and second members and thereby connecting of the throttle control lever to the engine throttle control only after such initial movement, said adjustable attachment means being releasably connected to the projecting portion for adjusting of the degree of initial movement and providing selected rotation of the throttle control lever from an idle position prior to engagement of the throttle control element, resilient means connecting the throttle lever to the timing lever for providing a resilient connection therebetween and for forcing the timing lever to follow the opening throttle movement of the throttle control lever, said timing lever having a stop means for limiting the rotation of the timing lever with the throttle lever, said resilient means permitting independent increasing throttle opening motion of the throttle lever.
A throttle control apparatus for internal combustion engines having a carburetor with a throttle input element and mounted in an outboard motor having a tiller handle with an outer twist grip, comprising a pair of push-pull cable members coupled to the twist grip to provide opposite motion of the cables in response to twisting of the twist grip, a common pivot pin secured to the engine block, a generally T-shaped throttle lever having a cross-bar pivotally mounted on said pin at the center of the cross-bar and having a stem projecting outwardly from the cross-bar, means connecting the opposite ends of the cross-bar to the respective two cables for providing selective pivoting of the lever between an idle position and an advanced throttle position in response to the rotation of the twist grip, a timing lever pivotally secured to said common pin in stacked relation of said T-shaped throttle lever and extending generally parallel thereto, said T-shaped throttle lever having said stem projecting forwardly toward the carburetor, a throttle control cam member located beneath said stem, adjustable coupling means connected to said cam member and said stem for adjusting the location of the cam member on the stem, a cam follower secured to the throttle element, said cam member having an outer cam face shaped with a space between the cam face and cam follower for an initial predetermined movement of the throttle lever and thereafter providing predetermined varying movement of the throttle input element in response with the angular orientation of the cam member relative to said throttle input, and a resilient means coupling the one end of the timing lever to the stem and stop means for limiting the the rotation of the timing lever.
Dependencies are inferred from the claim text.