| 主权项 |
1. Apparatus for forming a pattern of articles from a plurality of rows of articles being conveyed in a downstream direction on a conveyor to the apparatus, the conveyor of the type having a run that is movable in a downstream direction, the conveyor run having opposite first and second sides separated by a width of the conveyor run and an upper surface extending between the sides for supporting articles on the conveyor, the apparatus comprising:
a fence being selectively movable between a first position stationary along the conveyor path during pattern forming and a second position away from the conveyor path, the fence extending at least partially across the upper surface of the conveyor run and configured to obstruct movement of a row of articles moving downstream on the conveyor during pattern forming; the fence not obstructing movement of articles moving downstream on the conveyor when the fence is in the second position; a pattern forming device extending along a portion of the conveyor run upstream of the fence; the pattern forming device comprising first and second fingers on opposite sides of the conveyer run, the first finger adjacent the first side and the second finger adjacent the second side, the first and second fingers spaced across from each along an axis generally perpendicular to the first direction and defining an axial gap therebetween; the pairs of first and second fingers being in fixed positions along the conveyor path upstream from the first position of the fence; each finger movable along said axis between extended and retracted positions, each finger disposed over the conveyor belt when in the extended position, the fingers moving towards one another when moving together from their retracted positions to their extended positions and moving away from each other when moving together from their extended positions to their retracted positions; a controller operatively connected to the first and second fingers, the control unit comprising a first drive connected to the first finger and a second drive connected to the second finger, each of the first and second drives operable to selectively move the finger connected to the drive between the extended and retracted positions, the control unit configured to place the first and second fingers in their retracted positions prior to the articles reaching the fence; the first and second fingers being spaced from the fence such that a row of articles impacting the fence substantially simultaneously move into registration with the gap defined between the first and second fingers; the controller comprising a signal generator configured to generate a control signal when a row of articles moving downstream on the upper surface of the belt run moves into registration with the gap defined between the first and second fingers when the first and second fingers are in the retracted position; and the controller responsive to the control signal to move each of the first and second fingers from their retracted positions to their extended positions, the row of articles closely spaced between the first and second fingers when the first and second fingers are in their extended positions while forming the article pattern whereby the fingers resist displacement of the articles within the row of articles. |
