Apparatus for controlling sheet velocity

An apparatus for advancing a sheet, including:

• a moving imaging member having a toner image thereon with the sheet being adapted to receive the toner image from said imaging member;
• a fusing member including a rotatable fuser roll, and a pressure roll in contact with said fuser roll to define a nip through which the sheet passes for fusing the toner image to the sheet, said fuser roll and pressure roll being spaced from said imaging member a distance less than a distance between the sheet leading and trailing edges in the sheet direction of movement between said imaging member and said fuser roll;
• first drive means for moving said imaging member at a first velocity including a crystal clock which generates a fixed reference signal, a programmable divider adapted to receive the fixed reference signal and generate a control signal as a function thereof, and a servo motor responsive to the control signal;
• second drive means for rotating said fuser roll to advance the sheet at a second velocity;
• and
• a controller, in communication with said imaging member and said fusing member, to maintain the velocity of said fusing member at a selected relationship with that of said imaging member.

An apparatus for advancing a sheet, including:

• a moving imaging member having a toner image thereon with the sheet being adapted to receive the toner image from said imaging member;
• a fusing member including a rotatable fuser roll, and a pressure roll in contact with said fuser roll to define a nip through which the sheet passes for fusing the toner image to the sheet, said fuser roll and pressure roll being spaced from said imaging member a distance less than a distance between the sheet leading and trailing edges in the sheet direction of movement between said imaging member and said fuser roll;
• first drive means for moving said imaging member at a first velocity;
• second drive means for rotating said fuser roll to advance the sheet at a second velocity including a voltage controlled oscillator which generates a signal responsive to the velocity differential between said first drive means and said second drive means, a programmable divider adapted to receive the signal from said voltage controlled oscillator and generate a control signal based as a function thereof, and a servo motor responsive to the control signal;
• and
• a controller, in communication with said imaging member and said fusing member, to maintain the velocity of said fusing member at a selected relationship with that of said imaging member.

A printing machine of the type having a toner image developed on a moving photoconductive member adapted to be transferred to a sheet, wherein the improvement includes:

• a fusing member including a rotatable fuser roll, and a pressure roll in contact with said fuser roll to define a nip through which the sheet passes for fusing the toner image to the sheet, said fuser roll and pressure roll being spaced from the photoconductive member a distance less than a distance between the sheet leading and trailing edges in the sheet direction of movement between said photoconductive member and said fuser roll;
• first drive means for moving said imaging member at a first velocity including a crystal clock which generates a fixed reference signal, a programmable divider adapted to receive the fixed reference signal and generate a control signal as a function thereof, and a servo motor responsive to the control signal;
• second drive means for rotating said fuser roll to advance the sheet at a second velocity;
• and
• a controller, in communication with the photoconductive member and said fusing member, to maintain the velocity of said fusing member at a selected relationship with that of said photoconductive member.

A printing machine of the type having a toner image developed on a moving photoconductive member adapted to be transferred to a sheet, wherein the improvement includes:

• a fusing member including a rotatable fuser roll, and a pressure roll in contact with said fuser roll to define a nip through which the sheet passes for fusing the toner image to the sheet, said fuser roll and pressure roll being spaced from the photoconductive member a distance less than a distance between the sheet leading and trailing edges in the sheet direction of movement between said photoconductive member and said fuser roll;
• first drive means for moving said imaging member at a first velocity;
• second drive means for rotating said fuser roll to advance the sheet at a second velocity including a voltage controlled oscillator which generates a signal responsive to the velocity differential between said first drive means and said second drive means, a programmable divider adapted to receive the signal from said voltage controlled oscillator and generate a control signal based as a function thereof, and a servo motor responsive to the control signal;
• and
• a controller, in communication with the photoconductive member and said fusing member, to maintain the velocity of said fusing member at a selected relationship with that of said photoconductive member.