Patent ID: 7448292

Claim:
A transmission for transmitting a force comprising: a first rotation shaft coaxially fixed to a first turning transmission wheel; a second rotation shaft coaxially fixed to a second turning transmission wheel where the first and second rotation shafts are arranged in parallel with each other; a support shaft extended between the first turning transmission wheel and the second turning transmission wheel; a reciprocal movement mechanism that moves the support shaft to a first location which is close to the first turning transmission wheel and the second turning transmission wheel or a second location which is away from the first turning transmission wheel and the second turning transmission wheel; an intermediary transfer wheel formed on the support shaft rotatably and movably along a longitudinal direction of the support shaft; an intermediary transfer wheel feeding device that drives the intermediary transfer wheel, the intermediary transfer wheel feeding device comprising a moving arm, a drive mechanism that drives the moving arm in the longitudinal direction along the support shaft, and a feeding member provided at an end of the moving arm that moves the intermediary transfer wheel in the longitudinal direction along the support shaft; and a control unit for controlling operations of the reciprocal movement mechanism and the intermediary transfer wheel feeding device; wherein the first rotation shaft is rotated by a power device, and a rotational force of which can be transmitted to the second rotation shaft with variable speed; wherein each of the first turning transmission wheel and the second turning transmission wheel is formed in a shape of a right circular cone or a right circular cone trapezoid and has an identical vertex angle, and a tapered side peripheral surface of each of the first turning transmission wheel and the second turning transmission wheel faces each other with a constant distance; the support shaft is arranged between the side peripheral surface of the first turning transmission wheel and the side peripheral surface of the second turning transmission wheel such that it extends in the longitudinal direction along the side peripheral surface of the first turning transmission wheel and the side peripheral surface of the second turning transmission wheel; and wherein when the support shaft is in the first location, the intermediary transfer wheel contacts with each of the side peripheral surface of the first turning transmission wheel and the side peripheral surface of the second turning transmission wheel and is moveable in the longitudinal direction along the support shaft while maintaining the contact, and when the support shaft is in the second location, the intermediary transfer wheel separates from each of the side peripheral surface of the first turning transmission wheel and the side peripheral surface of the second turning transmission wheel.