An accountability system for a vendor having a cash handler, change tubes and a cash box, the cash handler being adapted to accept deposited coins and deliver them to the change tubes if needed, otherwise to deliver them to the cash box. A memory stores data on the amount of cash which should be retained...http://www.google.com.hk/patents/US4512453?utm_source=gb-gplus-share專利 US4512453 - Vendor accountability system
