Patent ID: 7766595

Claim:
A device for twisting a coil having a helical shape into perforations that are provided in the margin sections of flat components stacked one upon another, comprising: a drive engageable with the coil to subject the coil to rotation and an axial in-feed motion corresponding to an inclination of the helical shape, to twist the coil into the perforations; the drive comprising: a first cylinder having a shell with a smooth surface positionable against the coil, a second cylinder having a shell with a smooth surface positionable against the coil, wherein the second cylinder is located in a fixed position relative to the first cylinder, and the first cylinder and the second cylinder define a cylinder-pair for reception of the coil, a drive mechanism that drives the first cylinder in a rotating manner, and a notched bearing having notches to contact the threads of the coil, the notched bearing including a freely-turning notch cylinder, wherein a relative position between the first cylinder and the notched bearing is adjustable to receive the coil between the first cylinder and the notched bearing; a stopping device comprising a bar having a length that lies at an angle with respect to a moving direction of the coil, wherein the bar engages the coil to such an extent that the coil is stopped from being twisted into the perforations; and a releasing device comprising a lifting device that moves the cylinder-pair in a direction parallel to the length of the bar and brings the coil out of engagement with the stopping device to such an extent that the coil is released for further movement and is moved into engagement with the drive to twist the coil into the perforations.