Patent ID: 8115928

Claim:
A box inspector for detecting at an inspection station an unacceptable skew in, an item missing from, and an unacceptable gap in a box having a leading edge, a height, a width, a bottom opening closed by flaps defining the gap, and an open top, the box inspector comprising: at least two pairs of aligned emitters and receivers located in fixed positions at the inspection station and creating two spaced and parallel radiation beams through which the box to be inspected passes, each receiver generating a signal when the beam to be received by the receiver from the corresponding emitter is cut by the leading edge of the box; at least two item present sensors corresponding to the number of items adapted to be located in a single row within the box, the item present sensors being located in fixed positions at the inspection station, directing radiation toward the open top of the box, receiving radiation reflected from any items present in the box, and generating an item absent signal when an item is missing from the box; a gap detect sensor located in a fixed position at the inspection station under the box and between the flaps of the box when the box arrives at the inspection station, the gap detect sensor emitting radiation toward the box, detecting radiation reflected from the gap, and generating an unacceptable gap signal when the gap is larger than a predetermined gap size; a box present sensor directing radiation toward the box, receiving radiation reflected from the box, and generating a box present signal when the radiation indicates the presence of a box at the inspection station; and a controller (a) receiving signals from the receivers, the item present sensors, the gap detect sensor, and the box present sensor, (b) having a skew tolerance timer with a preset value, (c) generating an indication that the box is unacceptably skewed when the signals received from the respective receivers exceed the preset value, (d) generating an indication that an item is missing from the box when the signals received indicate that an item is missing and a box is present, and (e) generating an indication that an unacceptable gap exists in the box when the signals received indicate that the gap is larger than the predetermined gap size and a box is present.