Sequential rotary printing press web threading means

A rotary printing press assembly including apparatus for initially threading and conveying continuous webs of material therethrough comprising:

• a plurality of sequentially arranged printing units having said material webs pass serially therethrough;
• endless chain conveyors for each of said printing units for driving said materials;
• a lead-in bar attachable to said conveyors and capable of having said material web attached thereto;
• a gravure cylinder and impression cylinder between which said material web is engaged when passing through each of said printing units;
• a feeding station for each of said printing units for receiving said web prior to engagement thereof with said gravure cylinder and impression cylinder of each printing unit;
• a rotary field motor for driving said endless conveyor chains in each said printing unit during the threading operation;
• series-connected limit switches actuated by said lead-in bar for controlling operation of said rotary field motors;
• engagement and disengagement means for sequentially connecting said lead-in bar to said chain conveyor at each of said feeding stations of said printing units and for disengaging said lead-in bar when said lead-in bar has passed through said printing units to enable engagement thereof by the chain conveyor of a next succeeding printing unit;
• said engagement and disengagement means comprising
• a carrier bracket mounted on said chain conveyor,
• a pawl pivotally mounted on said carrier bracket,
• a locking bolt fixed to said carrier bracket,
• a cam surface formed on said lead-in bar adapted to be engaged by said pawl,
• a recess formed in said lead-in bar located to have said pawl guided by said cam surface into locking engagement therewith to effect driving of said lead-in bar by said chain conveyor, and
• a bore formed in said lead-in bar located to have said locking bolt engaged therein to hold said lead-in bar against lateral movement relative to the driving direction of said chain conveyor;
• a transfer station including means for actuating said engagement and disengagement means to disengage said lead-in bar from said chain conveyor when said lead-in bar has passed through a printing unit;
• said transfer station including means for transferring said lead-in bar between the chain conveyors of adjacent printing units;
• said series-connected limit switches being arranged to be actuated by said lead-in bar to start the rotary field motors of each of said conveyor chains when said lead-in bar introduces said material web thereinto and to stop said rotary field motors when said lead-in bar is transferred to a next adjacent printing unit;
• said material web being connected to one end of said lead-in bar and sequentially passed through said plurality of printing units by sequential engagement and disengagement of said lead-in bar with the chain conveyors of each of said printing units.