摘要 |
A web fed press has at least one press unit including a first web driving means driven by a first motor. Downstream from the press unit is a second web driving means, such as nip rolls, driven by a second motor. Encoders are associated with the motors to produce pulse trains which are compared for motor speed relationship. If the relationship is not correct, the energization of the second motor is varied to correct the error. The relative web speed at the two locations is adjusted by effectively varying the number of pulses per revolution produced by the encoder for the second motor. |