Derailleur

摘要

The present invention is a derailleur for moving a chain to a different sized sprocket in a drive sprocket nest comprising: a feed arm for directing onto one of multiple sprockets within the drive sprocket nest when the feed arm is rotatably mounted at a pivot end onto a frame of a vehicle; a take up roller attached to the feed arm supporting the chain so that when the take-up roller moves laterally the chain moves from one sprocket to another sprocket in the drive sprocket nets; a roller feel sprocket supporting the chain so that the chain contacts over ½ the perimeter of the sprocket contacting the chain in the drive sprocket nest; an opposite chain guide end attached to the feed arm so that the chain guide end traces a path substantially parallel to a tangent to the outer periphery of the drive sprocket nests.

主权项

1. A derailleur for moving a chain to a different sized sprocket in a drive sprocket nest comprising:
a guide feed arm for directing a chain between one of multiple sprockets of the drive sprocket nest wherein the guide feed arm is rotatably mounted to a pivot pin attached to and projecting from a frame of a vehicle at an angle defined between a lengthwise axis of the frame and a tangent intersecting the outer perimeter of the sprockets of the drive sprocket nest so that said guide feed arm rotates about said pivot pin; wherein said guide feed arm causes said chain to move from a first pedal sprocket to a second pedal sprocket so that the chain can be moved about said drive sprocket nest; a guide roller rotatably attached to said guide feed arm that supports the chain so that when said guide feed arm rotates about said pivot pin, said guide roller moves the chain from one sprocket to another sprocket in the drive sprocket nests; a take-up idler arm wherein an upper end of the take-up idler arm is pivotally attached to said guide feed arm; wherein when the take-up idler arm is centered on a middle sprocket, the guide roller and the take-up roller are both aligned parallel and in the same plane with the middle sprocket of the sprocket nest; and, wherein the take-up idler arm, when moved from alignment with the middle sprocket, is canted on an angle at either extremes of the smallest and largest sprockets wherein the guide roller and take-up roller are not aligned parallel and in the same plane relative to the respective smallest or largest sprocket creating a twist in the chain which is straighten out by a movement of the guide roller and take-up roller by using a gap or clearance between the take-up roller of the take-up idler arm; and, a take-up roller attached to an opposite end of the take-up idler arm for taking up chain slack when said guide feed arm rotates about said pivot pin, said opposite end traces a fixed planar arcuate path along a sweep angle set and controlled by the rotation about said pivot pin.