Article infeed gate and control therefor

Claim 1

An article handling mechanism comprising a driven conveyor having a rotary infeed worm rotatably supported by a horizontal shaft controlling movement of articles into a machine for treating articles, said infeed worm having an inlet receiving said articles and an outlet advancing them into said machine at equal spacings, said conveyor advancing said articles to said worm inlet and adapted for accumulating said articles upstream of said worm, a gate adjacent the inlet of said worm for controlling the supply of articles thereto comprising a wedge-shaped gate member supported for reciprocating movement laterally of the conveyor into and out the path of articles thereon, a reciprocating fluid-operated motor connected to actuate said gate member between an extended position into the path of articles for arresting their movement to the inlet of said worm and a retracted position for feeding articles thereto, said motor being operatively connected to a solenoid for regulating its said reciprocating movement, and means connected to the solenoid for causing operation of said motor in response to said accumulated articles comprising an electric energizing circuit connected to said solenoid for energizing the latter, at least one circuit closing qualifying contact in series in said circuit comprising a photoelectric switch device positioned across the conveyor upstream of said gate member and in the proximity thereof enabling actuation of said gate member to its retracted position by presence of articles on the conveyor opposite said switch device and actuation to its extended position when there are no articles opposite said switch device, the energizing circuit de-energizing the solenoid by insufficient upstream articles to cause said gate member to be moved to its extended position, and said qualifying contact being operable for energizing the solenoid by the presence of articles upstream of said gate member to cause it to be moved to its retracted position, and switch means in said energizing circuit and connected to the shaft of said rotary infeed worm operable for opening or closing said circuit at a predetermined point during a revolution of said shaft and synchronizing actuation of said gate member to its said extended and retracted positions, respectively, corresponding with a rotary position of said infeed worm, said switch means comprising plural proximity switches in circuit with said photoelectric switch and closed in response to a predetermined rotary position of the worm during each revolution for closing and opening said energizing circuit thereby synchronizing motor actuation to retract and extend said gate member so as to (a) retract said member responsive to rotational position of said rotary infeed worm to smoothly receive an article on the worm, and (b) extend said member for inserting it between adjacent articles passing in front of it.