Drive arrangement

摘要

A drive arrangement (10) has first and second wheels (12, 14) and an endless loop member (16). The path of the member (16) is defined in part by a third wheel (18), between the wheels (12, 14). The wheel (18) is movably mounted so that the length can be changed for the path of the member (16) as it passes around the wheel (18), between the wheels (12, -14). Accordingly, the member (16) can be tightened or slackened around the wheels (12, 14), so that the wheels (12, 14) can be coupled to convey drive from one to the other, through the member (16), or disengaged, so that drive is not conveyed.

主权项

1. A drive arrangement comprising:
first and second rotatable members; an endless loop member extending around both rotatable members; and a guide member which defines at least part of the path of the loop member; wherein the guide member is mounted on a pivotally mounted member and is movable to change the length of the path to cause the rotatable members to be engaged or disengaged by the loop member, the loop member serving to disengageably convey drive from one of the rotatable members to the other of the rotatable members when the rotatable members are engaged by the loop member, and further comprising a carriage structure movable relative to one of the rotatable members into and out of driving engagement with the said rotatable member, and wherein the carriage structure carries a toothed member which meshes with a mesh of the rotatable member when the carriage structure and the rotatable member are in driving engagement and a force applied between the pivotally mounted member and the carriage structure causes the pivotally mounted member to cause the guide member to move, the movement of the guide member causing the rotatable members to be engaged by the loop member and the force applied between the pivotally mounted member and the carriage structure causes the carriage structure to carry the toothed member out of mesh with the mesh of the rotatable member so that the rotatable member is disengaged by the toothed member.