Sheet position detector

Claim 2

A box machine for registering glued wraps with boxes and placing the boxes on the wrap, said machine comprising a frame, an indexed conveyor on said frame for transporting longitudinally spaced and glued wraps through a predetermined distance, means defining a registration station for registering a box with and applying it to a wrap, said registration station including a bracket member mounting a box gripper for initially holding a box above a wrap, means mounting said bracket member on said frame for shifting motion parallel to the motion of said conveyor, a wrap sensor on said bracket member for sensing a transverse edge of a wrap, an actuator for shifting said bracket member and wrap sensor, control means for said actuator including means for causing said actuator to position said bracket member in an initial position wherein a transverse edge of a wrap is adjacent to said sensor on completion of each indexing of said conveyor, said control means including means controlled by said sensor for causing said actuator to shift said bracket member longitudinally to a registration position where the sensor detects said transverse edge of the wrap, means for thereupon holding said bracket member in said registration position, and means for lowering the box gripper on said bracket member for applying the registered box onto said wrap.

Claim 3

The box machine of claim 1, wherein said box gripper comprises suction cups for engaging an upstanding wall of said box, means for lowering said cups to place a box on said wrap, and means connected to said bracket member and operable when said box is applied to said wrap for connecting said suction cups to a source of air at above atmospheric pressure air to release said box.

Claim 4

In a box machine including a longitudinally running conveyor belt for transporting wraps, a registration station including longitudinally shiftable means for gripping a box and applying it to a wrap, means to index said conveyor belt to locate successive wraps at said registration station, sensor means on said box gripping means and controlling an actuator for causing shifting of said box gripping means until a transverse edge of the wrap is detected by said sensor means whereupon the box is registered with the wrap, said sensor means comprising two laterally spaced but longitudinally aligned sensors disposed above said conveyor, said conveyor being formed with laterally spaced, longitudinal rows of longitudinally spaced individual apertures, the apertures in one row being staggered relative to those in the other row, the apertures in each row having a longitudinal extent greater than the spacing between adjacent pairs of apertures in the other row, each of said sensors being aligned with one of said rows of apertures, and circuit means connected to said sensors so that if either sensor overlies a conveyor belt aperture after indexing of said conveyor a shift signal is provided for shifting said box gripping means to bring said sensors toward a transverse edge of the wrap, said circuit means providing a stop signal when said transverse edge of the wrap is brought under either sensor to thereby stop the shifting movement of said box gripping means.

Claim 5

In a box machine including a longitudinally running conveyor belt for transporting wraps, a registration station including longitudinally shiftable means for gripping a box and applying it to a wrap, means to index said conveyor belt to locate successive wraps at said registration station, sensor means on said box gripping means and controlling an actuator for causing shifting of said box gripping means until a transverse edge of the wrap is detected by said sensor means whereupon the box is registered with the wrap, said sensor means comprising two laterally spaced but longitudinally aligned sensors disposed above said conveyor, said conveyor being formed with laterally spaced, longitudinal rows of longitudinally spaced individual apertures, the apertures in one row being staggered relative to those in the other row, the apertures in each row having a longitudinal extent greater than the spacing between adjacent pairs of apertures in the other row, each of said sensors being aligned with one of said rows of apertures, and circuit means connected to said sensors so that if either sensor overlies a conveyor belt aperture after indexing of said conveyor a shift signal is provided for shifting said box gripping means to bring said sensors toward a transverse edge of the wrap, said circuit means providing a stop signal when said transverse edge of the wrap is brought under either sensor to thereby stop the shifting movement of said box gripping means.

Claim 6

The box machine of claim 3, wherein each of said sensors comprises light emitting sources below said conveyor and photocells on said box gripping means.

Claim 7

The box machine of claim 3, wherein said sensor means comprises sonic sending and receiving units mounted, respectively, below said conveyor and on said box gripping means.

Claim 8

The box machine of claim 3, wherein said sensor means comprises fluid discharge and fluid receiving units mounted, respectively, below said conveyor and on said box gripping means.

Claim 9

The box machine of claim 1, wherein said actuator for moving said box gripping bracket member comprises a hydraulic linear actuator including a piston defining a rod-end liquid chamber and a head-end liquid chamber, means for simultaneously supplying liquid under pressure to one chamber while allowing liquid to be discharged from the other chamber for shifting said bracket member, and control means responsive to detection of the edge of said wrap for blocking flow of liquid from said other chamber for arresting the shifting of said bracket member.

Claim 10

A machine for assembling boxes with registered sheets including a conveyor for transporting longitudinally spaced glued sheets, a registration station associated with said conveyor, means at said registration station for retaining boxes and applying them to successive glued sheets, means for indexing said conveyor to locate successive glued sheets at said registration station, means for shifting said box retaining means in a plane parallel to said conveyor to center the box over the glued sheet, means on said box retaining means for detecting an edge of the glued sheet, and means for lowering the box onto said sheet; the improvement wherein said box retaining means is mounted for said shifting motion in a plane parallel to the conveyor only in a direction parallel to the direction of said conveyor motion, said detecting means sensing a transverse edge only of said glued sheet, said box shifting means comprising a control means responsive to said edge detecting means for shifting said box retaining means linearly and parallel to the direction of motion of said conveyor until said glued sheet edge is detected, said control means including means for thereupon arresting motion of said box retaining means to leave the box centered over the glued sheet.

Claim 11

A machine for assembling boxes with registered sheets including a conveyor for transporting longitudinally spaced glued sheets, a registration station associated with said conveyor, means at said registration station for retaining boxes and applying them to successive glued sheets, means for indexing said conveyor to locate successive glued sheets at said registration station, means for shifting said box retaining means in a plane parallel to said conveyor to center the box over the glued sheet, means on said box retaining means for detecting an edge of the glued sheet, and means for lowering the box onto said sheet; the improvement wherein said box retaining means is mounted for said shifting motion in a plane parallel to the conveyor only in a direction parallel to the direction of said conveyor motion, said detecting means sensing a transverse edge only of said glued sheet, said box shifting means comprising a control means responsive to said edge detecting means for shifting said box retaining means linearly and parallel to the direction of motion of said conveyor until said glued sheet edge is detected, said control means including means for thereupon arresting motion of said box retaining means to leave the box centered over the glued sheet.