초록 ▼

An internal combustion engine includes a crankcase and a crankshaft mounted vertically in the crankcase. The crankshaft has an end that extends outwardly from the bottom of the crankcase for attachment to a primary implement, such as a lawnmower blade, that is to be driven by the engine. Another end

An internal combustion engine includes a crankcase and a crankshaft mounted vertically in the crankcase. The crankshaft has an end that extends outwardly from the bottom of the crankcase for attachment to a primary implement, such as a lawnmower blade, that is to be driven by the engine. Another end of the crankshaft extends outwardly from the top of the crankcase and has a coupling to engage an accessory device. The accessory device may be permanently or removably attached to the engine. Preferably, a cover extends over the top of the crankcase and has an exterior surface from which a well extends toward the crankcase. The coupling projects into the well, but does not extend outwardly beyond the exterior surface of the cover so that the well thereby shields the rotating coupling from inadvertent contact by the user of the equipment on which the engine is mounted. A cap also may close the well when an accessory device is not connected to the coupling to further safeguard against inadvertent contact.

대표청구항 ▼

An internal combustion engine includes a crankcase and a crankshaft mounted vertically in the crankcase. The crankshaft has an end that extends outwardly from the bottom of the crankcase for attachment to a primary implement, such as a lawnmower blade, that is to be driven by the engine. Another end

An internal combustion engine includes a crankcase and a crankshaft mounted vertically in the crankcase. The crankshaft has an end that extends outwardly from the bottom of the crankcase for attachment to a primary implement, such as a lawnmower blade, that is to be driven by the engine. Another end of the crankshaft extends outwardly from the top of the crankcase and has a coupling to engage an accessory device. The accessory device may be permanently or removably attached to the engine. Preferably, a cover extends over the top of the crankcase and has an exterior surface from which a well extends toward the crankcase. The coupling projects into the well, but does not extend outwardly beyond the exterior surface of the cover so that the well thereby shields the rotating coupling from inadvertent contact by the user of the equipment on which the engine is mounted. A cap also may close the well when an accessory device is not connected to the coupling to further safeguard against inadvertent contact. path (31) opening into the second mixture-forming channel (17); a transfer passage (18) having a first end, connected to the combustion chamber (3) and having a transfer window (19) opening into the combustion chamber (3), and a second end (20) connected to the crankcase (4); wherein the first mixture-forming channel (28) leading to the storage duct (14) has a flow cross-section (d) that is smaller by more than one half than a flow cross-section (D) of the second mixture-forming channel (17) leading to the crankcase intake (16); and wherein, during idle of the internal combustion engine (1), the second fuel path (31) opening into the second mixture-forming channel (17) is substantially completely closed and fuel, required for operation, is supplied substantially exclusively via the first mixture-forming channel (28) leading to the storage duct (14). 2. The two-stroke engine according to claim 1, wherein, during idle of the internal combustion engine (1), combustion air is supplied substantially exclusively via the first mixture-forming channel (28) while the crankcase intake (16) is substantially closed. 3. The two-stroke engine according to claim 1, wherein, at least in one of partial load operation and full load operation, fuel supplied to the internal combustion engine (1) is supplied in a subordinate proportion via the second mixture-forming channel (17) and the crankcase intake (16). 4. The two-stroke engine according to claim 3, wherein fuel supplied to the combustion engine (1) is supplied in a proportion of approximately 0% to 35% via the second mixture-forming channel (17) and the crankcase intake (16). 5. The two-stroke engine according to claim 1, wherein the ratio (V=d/D) of the flow cross-section (d) of the first mixture-forming channel (28) leading to the storage duct (14) relative to the flow cross-section (D) of the second mixture-forming channel (17) leading to the crankcase intake (16) is in a range of 1/2 to 1/12. 6. The two-stroke engine according to claim 1, wherein the first mixture-forming channel (28) has a mixture-forming channel throttle (40) configured to change the flow cross-section (d) of the first mixture-forming channel (28). 7. The two-stroke engine according to claim 6, wherein the second mixture-forming channel (17) has an intake passage throttle (29, 30, 49) configured to change the flow cross-section (D). 8. The two-stroke engine according to claim 7, wherein the mixture-forming channel throttle (40) and the intake passage throttle (29, 30, 49) are coupled position-dependently with one another. 9. The two-stroke engine according to claim 8, wherein the mixture-forming channel throttle (40) and the intake passage throttle (29, 30, 49) are coupled with opposite orientation such that the first mixture-forming channel (28) is open and the second mixture-forming channel (17) is closed during idle and the mixture-forming channel (28) is throttled and the second mixture-forming channel (17) is open under full load operation. 10. The two-stroke engine according to claim 9, wherein the mixture-forming channel throttle (40) and the intake passage throttle (29, 30, 49) are selected from the group consisting of a throttle blade (30, 40), a rotary sleeve valve (29), and a throttle slide (49). 11. The two-stroke engine according to claim 1, wherein the flow cross-section (d) of the first mixture-forming channel (28) is unchangeably fixed. 12. The two-stroke engine according to claim 1, wherein the flow cross-section (D) of the second mixture-forming channel (17) is unchangeably fixed. 13. The two-stroke engine according to claim 1, wherein one of the first and second fuel paths (341, 41) is a controllable fuel path. 14. The two-stroke engine according to claim 1, wherein the controllable fuel path (41) is mechanically controllable. 15. The two-stroke engine according to claim 14, wherein the controllable fuel path comprises a valve (42). 16. The two-stroke engine according to claim 15, wherein the v