A programmable size and price-setting mechanism for use in a vending machine has a plurality of n access doors aligned horizontally across a front of the vending machine, each of which access doors has a locked condition denying access therethrough and an unlocked condition allowing access therethrough,...http://www.google.com/patents/US5511646?utm_source=gb-gplus-sharePatent US5511646 - Multiple price and size setting method for vending machines
