Patent ID: 9273659
Filing Date: 2016-03-01
CPC Classification: F02N

Claim Text:
1. A rope-pull starting device for an internal combustion engine, the starting device comprising: a hub configured to drivingly engage an internal combustion engine when the hub is rotated in a first direction; a rope pulley interconnected with the hub by a torsion damper spring; a rope coiled, from an anchored end thereof, about the rope pulley in the first direction; and the torsion damper spring coupled at a first end to the hub and at a second end to the rope pulley, wherein the torsion damper spring is coiled from the first end connected to the hub, toward the rope pulley, in a second direction opposite to the first direction, and whereby the rope pulley is rotated in the first direction when the rope is pulled and unwound therefrom and the torsion damper spring responsively urges the hub to rotate in the first direction and drivingly engage the internal combustion engine; the rope pulley and the hub each have an annular recess formed therein about respective rotational axes thereof and wherein the two annular recesses are substantially aligned, one with the other, thereby forming a common annular recess for receiving therein coils of the torsion damper spring, wherein the torsion damper spring has a first diameter in a relaxed state and a second diameter in a loaded state, the first diameter being smaller than the second diameter and wherein the common annular recess has an outer diameter that is substantially the same as the second diameter of the torsion damper spring and prevents the diameter of the torsion damper spring from exceeding a predetermined amount, wherein the torsion damper spring elastically deforms between the relaxed state and loaded state and correspondingly accommodates between sixty degrees and three hundred sixty degrees of relative angular rotation (alpha) between the first end and second end of the torsion damper spring between the relaxed state and loaded state.