Patent ID: 6637575
Filing Date: 2003-10-28
Classification: B60N,G05G,Y10T

Abstract:
A ratchet actuator comprising:a lever; a ratchet arm having a drive axis and a ratchet axis, said ratchet arm being fixed to said lever at said drive axis; a ratchet comprising: a ratchet post, said ratchet post being coaxial with and fixed to said ratchet arm ratchet axis; a first pawl having a first end in rotating communication with said ratchet post and having a second end, said second end having teeth and a pin; at least one second pawl having a first end in rotating communication with said ratchet post and having a second end, said second end having teeth and a pin; a pawl spring biasing said first pawl second end towards said second pawl second end; a drive gear having teeth, said drive gear teeth being dimensioned to mesh with said first and second pawl teeth and said drive gear being disposed to engage said pawls, said drive gear having at least two fingers projecting perpendicular to the plane of the gear; a ring having a high step and at least one low step; each of said steps being disposed to mediate said pawl spring biasing of each of said pawls towards the other of each of said pawls by sliding contact with said pins; such that when one of said first or second pawl pins is in contact with said at least one low step, the other of said pins remains in contact with said high step; said low step being dimensioned to mesh said teeth of said one of said pawl ends having said pin contacting said low step with said teeth of said drive gear; and said high step being dimensioned to keep said teeth of said other pawl end having said pin contacting said high step disengaged from said drive gear teeth; a hub having at least two bosses defining at least two spaces between said bosses; said hub having at least two edges forming one side of each of said spaces and said each of said edges being dimensioned with a first hub distance and a second hub distance from a center of said hub with said edge being graduated from said first distance to said second distance, said hub being circumscribed by said ring, said ring having an inner surface, said inner surface being in sliding rotational communication with said bosses, said inner surface defining another side of each of said spaces, and said at least two spaces receiving said at least two fingers from said drive gear; at least two locking rollers, disposed in said spaces said locking rollers being narrower in diameter than a distance between said ring inner surface and said hub edge first distance and said rollers being wider in diameter than a distance between said ring inner surface and said edge second distance; and at least two springs disposed between said bosses and said locking rollers such that said springs bias said locking rollers from said first distance and toward said second distance; a traction element anchor; and a housing encapsulating said ratchet arm, said ratchet, said drive gear, said ring, said hub, said springs and said traction element anchor.