An anti-theft assembly for carts including a housing adapted to fit adjacent a wheel of a cart, a receiver within the housing for sensing the passage of the cart beyond a preselected range and providing a signal indicative thereof, and an arrangement responsive to the signal for lowering an arm into...http://www.google.fr/patents/US4772880?utm_source=gb-gplus-shareBrevet US4772880 - Shopping cart anti-theft system
