Automatic strip and sheet loader system

A method for feeding single sheets from a stack of similar sheets positioned in the magazine of a sheet feeding mechanism having sheet vacuum pickup means, separator means and sheet drive roll means, comprising the steps of

• driving said vacuum pickup means into contact with the top surface of the stacked similar sheets near one end thereof,
• applying vacuum to said vacuum pickup means to effect bending of the topmost of said stacked sheets to effect its separation from lower sheets,
• raising said pickup means and said topmost sheet to increase sheet separation of said topmost sheet,
• driving said separator means beneath and along the length of said topmost sheet from the picked up end to the far end thereof and stopping there to support said topmost sheet's far end in contact with said sheet drive roll means, and
• activating said drive roll means to eject said topmost sheet from said sheet feeding mechanism.

A sheet separating system for separating one end of an outside sheet from a stack of sheets and moving the end of said outside sheet away from the remaining stacked sheets comprising:

• pickup head means for gripping, bending and moving said outside sheet comprising
• a holddown pad,
• one or more primary vacuum bellows movable material grippers between said holddown pad and the end of said outside sheet,
• one or more secondary vacuum bellows movable material grippers on the opposite side of said holddown pad,
• actuator means to move said pickup head means in a direction approximately normal to the plane of said stacked sheets,
• vacuum sensor means for sensing contact of all of said material grippers with said outside sheet and providing an output signal in response thereto, and
• control system means connected to said pickup head means, said actuator means and said vacuum sensor means to effect operation of said pickup head means and said actuator means in response to predetermined instructions and the output of said vacuum sensor means.

A sheet separating system for separating one end of an outside sheet from a stack of sheets and moving the end of said outside sheet away from the remaining stacked sheets comprising:

• pickup head means for gripping, bending and moving said outside sheet comprising
• a holddown pad,
• one or more primary movable material grippers between said holddown pad and the end of said outside sheet,
• one or more secondary movable material grippers on the opposite side of said holddown pad,
• actuator means to move said pickup head means in a direction approximately normal to the plane of said stacked sheets,
• vacuum sensor means for sensing contact of all of said material grippers with said outside sheet and providing an output signal in response thereto,
• control system means connected to said pickup head means, said actuator means and said vacuum sensor means to effect operation of said pickup head means and said actuator means in response to predetermined instructions and the output of said vacuum sensor means, and
• separation enhancer means comprising at least one fixed member arranged to protrude into the path of sheets being raised by said pickup head means by an amount to clear the topmost sheet but positioned to interfere with additional sheets being lifted by said pickup head means.

The method for effecting topmost sheet separation from plural stacked sheets disposed in a sheet feeding system and feeding said topmost sheet on command from an associated machine, said sheet feeding system comprising sheet pickup head means including one or more gripper means and sheet holddown means, separator means and sheet drive roll means, the improvement comprising the steps of

• initiating a return to home signal in response to a power on condition to cause said pickup head means and said separator means to drive to a home position First system condition,
• initiating a topmost sheet pickup and separation sequence upon receipt of a start signal, said sequence comprising,
• driving said pickup head means from said home position to a position where said sheet holddown means and said gripper means are in contact with the top surface of said topmost sheet near the home position end thereof,
• actuating said gripper means to effect bending of said home position end of said topmost sheet to effect a separation condition of said end from the stacked sheets remaining therebelow and effect a Second system condition,
• driving said pickup head means with said topmost sheet gripped thereby away from said remaining stacked sheets and to said pickup head's home position and effect a Third system condition, and
• initiating a separator means drive signal to effect movement of said separator means from home position beneath said topmost sheet to a full forward position completing separation of said topmost sheet and supporting said topmost sheet at said full forward position in contact with said sheet drive roll means, and effect a Fourth system condition,
• initiating a control signal to turn said drive roll means on and said gripper means off upon receipt of a command signal from said associated machine and thereby eject said topmost sheet from said sheet feeding system to said associated machine and thereby achieve a machine clear Fifth system condition, and
• initiating a return to home signal upon completion of said topmost sheets ejection to cause said separator means to return to a home position Sixth system condition and to turn off said drive roll means.