Abstract: A flexible coupling is disclosed for joining together shaft sections to form one continuous shaft which may be rotatably driven by a drive means provided at one end of the continuous shaft.

Abstract: A mechanism is provided for securing a paper driving tractor device along a relatively thin elongate member effective in the released condition to permit the tractor to be positioned at will along said elongate member while in the locked condition enabling, positive, secured, engagement of the tractor with said elongate member effective to prevent any movement of the tractor relative to said member, also permitting locking an elongate member repeatedly at the same position without affecting the original characteristics of the elongate member.

Abstract: Apparatus for securely locking tractor pin drive apparatus against unintended movement transverse to the movement of the paper being fed by the device comprising a split U-shaped clamping member surrounding an elongated support means carrying the tractor and secured to the tractor body. A flat sided, threaded, bolt having a cam release and locking lever attached to one end and an adjusting self-locking means secured to the other end thereof secures the ends of the U-shaped clamp together. Movement of the lever affords quick cam release of the tractor mechanism with respect to the transverse support by engaging and disengaging the clamp from the support. Adjustment of the bolt alters the degree of clamping force between the clamp and the support.