Patent GB-767758-A (GB)
Title: Improvements in or relating to apparatus for the preselective control of the delivery of liquid from a liquid metering unit
IPC: G07F7/02
Filed: 1954-08-16
Abstract: 767,758. Electric selective signalling systems. TODD, B. J. Aug. 16, 1954 [Aug. 18, 1953; Aug. 12, 1954], No. 23828/54. Class 40 (1). [Also in Groups XVIII and XL (c)]  In a device for permitting a predetermined quantity of petrol to be delivered from a petrol pump in response to receipt of a punched card, the device comprises a selective signalling system whereby any punched card having a hole punched in one of several positions in each of a predetermined number of appropriately positioned rows will operate the device to permit delivery of petrol, providing that the customer at the time of inserting the card dials a number corresponding to the combination of the holes in the card. As shown, the card 212 is provided with four punched holes 221, one in each of four rows, each having ten positions 220. The card is inserted in a tray 211 between roller 266 and spring-loaded roller 216 whereby closing contacts 217, further movement being prevented by a stop 214. Closure of contacts 217 energizes solenoid 218 which unlatches the gate 214. The customer now raises a hinged cover on a telephone type dial 208 adjacent the tray 211 and thereby closes a switch 210 energizing relay O. This causes energizing of a solenoid 219 which drops a sensing rack comprising four rows of brushes 222 so that the brushes engage the rows of positions on the card and those in register with holes in the card make contact with a base plate 223. The brushes are connected to corresponding contacts of four banks of con. tacts associated with respective uniselectors U1-U4, the moving arm of each of which except the last being connected to the base plate of the row of brushes associated with the next bank, and the last arm 261 being connected to a uniselector coil 277 and to a relay P. Each of the uniselectors is a reverse-drive uniselector. In operation, the uniselector arms 246, 251, 256 and 261 are actuated in turn by successive diallings on the dial 208, the successive dialling being routed to the coils 238-241 of the uniselectors in turn by means of a further reversedrive uniselector U5. Each time a number is dialled contacts 230 are closed and opened a corresponding number of times, intermittently energizing one of the coils 238-241 through arm 235 and one of its associated contacts and, as the dial returns for a fresh dialling, contacts 229 are closed and opened, energizing coil 231 of uniselector U5 and causing arms 235, 236, 237 of uniselector U5 to move one step whereby arm 235 connects contacts 230 to the next one of the coils 238-241, and so on. Thus upon completion of a correct dialling the positions of arms 246, 251, 256 and 261 correspond with those brushes which contact the bases of the sensing rack through the holes in the card. A circuit is thus completed to coil 277 of a uniselector USa and a relay P which sets a flap 280 in position to divert the card after sensing to an " accepted cards " compartment. Also on completion of dialling, uniselector arms 235-237 are moved on a fourth step so that a circuit is completed through arm 236 and fired bank 263 to a slugged relay N which energizes a motor 265 driving rolls 266 and also energizes a solenoid 215 which retracts the gate 214. The card thus passes via flap 280 to the " accepted cards " compartment 283. The slugging of relay N prevents it from being actuated by brief pulses of current via the various uniselector resetting contacts 265 and 307, and ensures that it remains energized until the card has passed the flap 280, although its circuit is broken when the card leaves the sensing rack. The subsequent breaking of the circuit to the coil 277 of uniselector USa causes the arms 313, 314 of this uniselector to move one step corresponding to the preselection of one gallon of petrol. If now the dial gate be closed relay O is de-energized and a resetting circuit for the uniselectors U1-U5 is completed through contacts O1o resetting the arms of these uniselectors. Also relay Q is again energized through contacts O2o so that a fresh card may be inserted, this card, if accepted, causing arms 313, 314 to move a further step, and so on. The sensing rack is provided with an extra row of brushes 279 positioned ahead of the punched holes. If a card is forged by cutting a slot or slots a resetting circuit is completed through brushes 279 to relay N which causes the card to be passed to the " rejected cards " compartment 282 since the solenoid 281 operating flap 280 has not been energized. The card is also rejected and no petrol preselected if the wrong four numbers are dialled, since no circuit will be completed to the uniselector coil 277 and solenoid 281 is not energized. When one or more cards have been accepted the customer may take delivery of petrol by removing the delivery nozzle of the pump from its holster and opening the delivery valve, the supply being automatically cut off and arms 313, 314 of uniselector USa react to zero after delivery of the preselected volume (see Group XVIII). Specification 753,486 (Group XVIII) is referred to.