Abstract: A cart immobilizing mechanism responding to signals prescribing a permitted use area for the cart is contained entirely within a wheel of the cart. This mechanism preferably includes a circuit board containing a radio frequency receiver, a decoder, and a logic driver. The mechanism also includes a solenoid device. When the receiver detects that the cart has been moved outside the prescribed use area, the solenoid device is energized to drive its armature into an opening in a non-rotating shaft supporting a wheel, thereby locking the wheel against rotation and immobilizing the cart.

Abstract: A machine for conveying similarly shaped articles in a single file is disclosed comprising drive and return conveyors with said drive conveyor having a loading portion and a discharge portion. A plurality of similarly shaped articles are loaded at the loading portion of the drive conveyor. A separator separates the articles in a single file on the drive conveyor and ejects articles from the drive conveyor which vary from the single file. The return conveyor forms an angle relative to the drive conveyor for receiving the ejected articles from the drive conveyor to return the ejected articles on the return conveyor to the drive conveyor.