Abstract: A continuous web of sheet material is fed through the lip of a first pair of driven pull rolls around a series of idler rollers and through the nip of a second pair of driven pull rolls. The pairs of pull rolls are selectively rotated to exert a desired tension on the web in a tension zone formed between the pairs of rolls. One pair of pull rolls operates as feed rolls to advance a preselected length of the web to a rotating cutter mechanism so that envelope blanks of a selected length are cut from the web for each revolution of the cutter mechanism. The feed rolls are operated by a servo-controlled motor responsive to an operator initiated signal to adjust the feed length without interrupting the feed of the web to the cutter mechanism. The second pair of pull rolls operates as tension rolls and is servo-motor controlled to maintain a preselected tension on the web fed to the cutter mechanism.

Abstract: A continuous web of sheet material is fed through the nip of a first pair of driven pull rolls around a series of idler rollers and through the nip of a second pair of driven pull rolls. The pairs of pull rolls are selectively rotated to exert a desired tension on the web in a tension zone formed between the pairs of rolls. One pair of pull rolls operates as feed rolls to advance a preselected length of the web to a rotating cutter mechanism so that envelope blanks of a selected length are cut from the web for each revolution of the cutter mechanism. The feed rolls are operated by a servo-controlled motor responsive to an operator initiated signal to adjust the feed length without interrupting the feed of the web to the cutter mechanism. The second pair of pull rolls operates as tension rolls and is servo-motor controlled to maintain a preselected tension on the web fed to the cutter mechanism.

Abstract: A pair of pull rolls unwind web material from a roll and advance the web at a preselected linear feed rate to a web cutting mechanism. The pull rolls are rotated at a preselected speed to generate the desired linear speed rate for cutting the web at selected intervals to produce blanks of a preselected length. The feed rolls are driven by a servo-motor which is operated by a controller that is microprocessor controlled. The controller is electrically connected to an encoder that is drivingly connected to a rotating knife cylinder of the web cutting mechanism. A selected length of blank to be cut from the web is inputted by the operator through a keypad to transmit a corresponding signal to the controller. In addition, the controller receives a signal from the servo-motor that drives the pull rolls, which signal is representative of the rate of rotation of the pull rolls.