Arrangement for controlling the intake air for the carburetor of a hand-held portable tool
AssigneeAndreas Stihl AG & Co. KG
InventorsKlaus Hoppner, Bernhard Kiefel
Life of this patent
Estimating the term…
Abstract
The invention is directed to an arrangement for controlling the intake air for the carburetor of a hand-held portable tool such as a motor-driven chain saw or the like. During winter operation, the cooling air that is heated by the engine cylinder is carried through a pass-through opening to the carburetor. During summer operation the pass-through opening is blocked by a slide that is pivotally mounted on a pivot axis. The slide selectively opens or closes the pass-through opening and is configured as a deflector which, in its open position baffles the heated cooling air from the engine cylinder and guides it toward the carburetor.
Claims27
Arrangement for controlling the intake air for a carburetor of a hand-held portable tool such as a chain saw or the like which is suitable for both cold weather and hot weather operation, the portable tool also including a housing and an engine having a cylinder mounted in the housing, the arrangement comprising:
- pass-through passage means for passing heated cooling air from the cylinder across a gap in the housing to adjacent the inlet of the carburetor air cleaner during cold weather operation;
- a slide pivotally mounted in said housing and means for selectively moving the same about a pivot axis between a first position whereat said pass-through passage means is closed during hot-weather operation and a second position whereat said pass-through passage means is open so as to permit passage of said heated cooling air therethrough during said cold weather operation;
- and,
- said slide being configured as a deflecting member for baffling said heated cooling air and then guiding the same in the direction toward said carburetor.
Arrangement for controlling the intake air for a carburetor of a hand-held portable tool such as a chain saw or the like which is suitable for both cold weather and hot weather operation, the portable tool also including a housing and an engine having a cylinder mounted in the housing, the arrangement comprising:
- pass-through passage means for passing heated cooling air from the cylinder to the carburetor for cold weather operation;
- a slide pivotally mounted in said housing and means for selectively moving the same about a pivot axis between a first position whereat said pass-through passage means is closed during hot-weather operation and a second position whereat said pass-through passage means is open so as to permit passage of said heated cooling air therethrough during said cold weather operation;
- said slide being configured as a deflecting member for baffling said heated cooling air and then guiding the same in the direction toward said carburetor;
- said housing including a transverse wall disposed between said carburetor and said engine, pass-through passage means being a pass-through opening formed in said transverse wall;
- and a cover covering said engine;
- said slide being pivotally mounted on said cover in the vicinity of said pass-through opening;
- said slide including a slide wall configured as a longitudinally extending portion of a cylinder and defining a concave wall surface for deflecting said heated cooling air toward said carburetor when said slide is in second position;
- said cover having a roof wall adjacent said transverse wall, said slide further including a base plate;
- and, pivot means for pivotally journalling said base plate on said roof wall, said slide wall mounted on said base plate so as to extend transversely therefrom;
- said pivot means including a journalling boss formed on said roof wall for pivotally journalling said base plate thereon;
- and, a threaded fastener threadably engaging said boss for holding said base plate on said boss;
- said pivot means further including a sleeve formed on said base plate for pivotally engaging said journalling boss;
- said slide wall having longitudinally extending edges and being mounted to said base plate so as to extend downwardly therefrom, said base plate being a triangularly shaped member having an apex whereat said sleeve is formed and having lateral side edges extending to respective ones of said longitudinal edges of said slide wall;
- and,
- said cylinder having a cooling rib extending in a direction parallel to said pivot axis, said slide being mounted on said cover so as to cause one of said longitudinal edges to be in seal-tight contact with said cooling rib when in said second position.
Arrangement for controlling the intake air for a carburetor of a hand-held portable tool such as a chain saw or the like which is suitable for both cold weather and hot weather operation, the portable tool also including a housing and an engine having a cylinder mounted in the housing, the arrangement comprising:
- the housing including a wall spaced from said engine;
- said wall and said engine conjointly defining pass-through passage means for passing heated cooling air from the cylinder to the carburetor for cold weather operation;
- and,
- a slide mounted in said housing and means for selectively moving the same between a first position whereat said pass-through passage means is closed during hot-weather operation and a second position whereat said pass-through passage means is open so as to pass heated cooling air to the carburetor during said cold weather operation;
- and,
- said slide being configured as a deflecting member for baffling said heated cooling air and then guiding the same in the direction toward said carburetor.
Dependencies are inferred from the claim text.