No-feed-roll corrugated board or paperboard sheet feeder retrofit apparatus and method

A sheet feeder apparatus for supplying sheets from the feeder apparatus to a sheet processing host machine having a predetermined nominal sheet velocity, comprising:

• (a) a first set of drive elements for driving a sheet through a first velocity zone in said feeder apparatus;
• (b) a second set of drive elements for driving the sheet through a second velocity zone in said feeder apparatus;
• (c) a controller for said feeder apparatus, wherein the controller is configured to:
• supply a first set of drive signals to said first set of drive elements for controlling the velocity of said sheet in said first velocity zone in a first motion profile having an initial sheet velocity lower than said host machine nominal velocity and a second sheet velocity higher than said host machine nominal velocity as the sheet passes through the first velocity zone;
• and
• supply a second set of drive signals to said second set of drive elements for controlling the velocity of said sheet in the second velocity zone in a second motion profile having an adjustable constant sheet velocity equal to said host machine nominal velocity to deliver said sheet to said host machine at said nominal velocity;
• (d) first and second control surface sets in said first and second velocity zones, respectively, movable to expose and conceal said first and second sets of drive elements;
• and
• wherein the controller is further configured to generate first and second control surface signals to move said control surface sets through a sequence of positions to selectively provide contact between said drive elements and said sheet to drive said sheet at a variable velocity in accordance with said first and second motion profiles.

A computer controlled corrugated board sheet feeder apparatus configured to retrofit a pre-existing host corrugated board processing machine, comprising:

• a feed table surface for receiving corrugated boards at a feed end and moving them to a delivery end;
• first drive wheels mounted in a first variable velocity zone of said table surface to drive boards sequentially in a first motion profile through a first vacuum zone;
• second drive wheels mounted in a second velocity zone of said table surface to drive boards received from said first velocity zone in a second motion profile through a second vacuum zone to the delivery end;
• a controller configured to receive predetermined velocity signals from the host machine to generate a first variable velocity control signal for the first variable velocity zone and a second velocity control signal for the second velocity zone based on the predetermined velocity signals from the host machine,
• a dedicated primary servo motor in the first variable velocity zone configured to perform said first motion profile based on the first variable velocity control signal,
• wherein the controller is configured to control the primary servo motor to perform the first motion profile including accelerating a board to a velocity above a velocity of the host machine and then decelerating the board to the velocity of the host machine;
• a variable vacuum generator and variable control surface in each of said first and second velocity zones;
• wherein said control surfaces in said first and second velocity zones are mounted above corresponding drive wheels in said zones to prevent boards from contacting said drive wheels;
• and
• a drive mechanism for each said control surface to independently lower and raise said control surfaces to sequentially engage boards with selected drive wheels as boards are fed through said feeder apparatus and into the host machine;
• wherein the controller is configured to control the variable vacuum generators and the drive mechanisms of said control surfaces of said first and second velocity zones.