Valve drive mechanism for outboard motor
AssigneeYamaha Marine Kabushiki Kaisha
InventorToshihiro Nozue
Life of this patent
Estimating the term…
Abstract
An engine has a crankshaft. The crankshaft has a set of steps formed at one end. A drive pulley for a cam drive arrangement is positioned on one of the steps. A set of holes are formed in the end of the crankshaft adjacent to the steps. The holes has axes that are substantially parallel with a rotational axis of the crankshaft. Threaded fasteners that screw into the holes couple the crankshaft and the drive pulley. An alignment pin also extends between the drive pulley and the crankshaft. A position sensor component such as a washer is interposed between the crankshaft and the drive pulley.
Claims19
An engine for an outboard motor, said engine comprising an engine case, a crankshaft extending through said case in a generally vertical direction, said crankshaft projecting upwardly from said engine case and having a rotational axis, said crankshaft having a stepped configuration defined by a reduced diameter portion, said crankshaft also having a surface that is generally normal to said rotational axis and that abuts said reduced diameter portion, a drive pulley mounted on said crankshaft on said reduced diameter portion, a flexible transmitter connecting a driven pulley to said drive pulley, the driven pulley being mounted to a cam shaft, and a plurality of fasteners joining said drive pulley to said crankshaft, each of said plurality of fasteners having a center axis that extends generally parallel to said rotational axis of said crankshaft and extending into a blind hole having an opening on said surface.
An engine comprising an engine case, a generally vertically extending crankshaft journalled for rotation within said engine case, a bearing supporting a portion of said crankshaft within said engine case, said crankshaft having an upper end extending beyond said engine case, said upper end of said crankshaft defining a first diameter and a second diameter, a face surface being defined at a transition between said first diameter and said second diameter, a drive pulley mounted to said crankshaft, and a plurality of fasteners, each comprising an external thread and extending into said face surface to affix said drive pulley to said face surface.
An engine comprising an engine case, a crankshaft being journalled for rotation within the engine case, the crankshaft having an end portion extending beyond the engine case, the end portion having a first diameter and a second diameter together defining a step area therebetween, the step area extending generally normal to a rotational axis of the crankshaft and having at least one blind hole extending generally parallel to and offset from the rotational axis of the crankshaft, a drive pulley abutting on the step area and extending coaxially with the crankshaft, and at least one threaded fastener extending downward through the drive pulley to terminate within the blind hole.
Dependencies are inferred from the claim text.