Patent GB-993142-A (GB)
Title: Currency detectors
IPC: G07D7/00
Filed: 1961-05-29
Abstract: 993,142. Checking cash. NATIONAL REJECTORS Inc. May 26, 1961 [Oct. 20, 1960], No. 19258/61. Heading G4T. Apparatus for identifying authentic currency bills comprises members for gripping a bill and feeding it to a sensing system including a sensing head with an airgap, means for moving the bill intimately against the sensing head, said means being operated by the bill, and means under the control of the sensing head for causing an unacceptable bill to be fed in a direction opposite to that in which it entered the apparatus. The apparatus may be associated with a vending or a change-giving machine. A spurious bill is returned, as is also a genuine bill if a withdrawing card &c. is attached to it. The bills are printed in magnetic ink in known manner, and they pass under a magnetic head which controls the feed of the bills. The conveying means comprises two pairs of opposed timing belts 270, 272 which are spaced apart to engage the two sides of a bill, and the bill is fed along a horizontal path defined by two spaced-apart platens 50, 94 provided with edge guide plates to prevent skewing of the bill. The top belts 270 are supported on toothed pulleys 204, 164, the front pulleys 204 being vertically movable against spring action by a solenoid 230 which acts through levers 224, 214, and 207, so that a bill placed on a support 336 can be placed between the belts. The lower belts 272 are mounted on toothed pulleys 180, 194, the pulleys 180 being driven by a reversible motor 188 through worm gearing: the shaft of the pulleys 180 is geared to the shaft 162 of the pulleys 164, so that both sets of belts are driven in synchronism and without slip. Each belt is supported opposed wear-resisting guides 260 which also engage the sides of the belts, and the arrangement is such that there is alternate downward and upward bowing of the belts causing them to undulate as they travel, causing undulations in the currency bill gripped between them, and thus stiffening the bill and eliminating any wrinkles &c. therein. The bills are inserted through a slot in the front plate 36, and pass through a slot in a gate 370 which is lowered, when a bill has been fully fed into the apparatus, by a solenoid 344 acting through levers 350, 352. Each bill is adapted to depress a number of curved switch arms, such as 276, 288, to operate switches, such as 274, 286, arranged between the feed belts. The bills are delivered to a cash box &c. by opposed pairs of sift faced rollers 314, 321, the shafts of the rollers 314 being driven by a belt and pulley arrangement and a spring clutch 168, 170, 176 from the shaft 162, whereby the rollers travel faster than the speed of the belts. When the rollers 314, 321 first engage a bill, they cannot rotate at their normal rate, the torsion spring 176 of the clutch drive is thus wound tighter, thereby storming energy within itself. When the trailing edge of the bill leaves the feed belts 270, 272, the spring 176 will restore itself to normal condition, the rollers 314, 321 will be rapidly rotated, and the bill will be ejected at high speed. The magnetic head 244 of the currency detector is slidably mounted on the limbs of a U-shaped frame 238, and is biassed downwardly by a spring 246 on an adjustment screw device 248. A soft-faced roller 326 co-operating with the head 244 is carried by a bell-crank lever 323 which is connected by a link 334 to a solenoid 330. Operation:- When the leading edge of a bill is inserted between the timing belts 270, 272 and a start button 340 is depressed, the solenoid 230 is energized to allow springs 208 to force downwardly the belt pulleys 204 so that the bell is gripped by the belts, and the motor 188 is then energized by a switch 232 operated by the solenoidoperated lever 214 to cause the bill to be fed. The circuit connections established by the button 340 are maintained and further connections are made, by the bill depressing switch arms, such as 276 and 286, so that as the bill is fed the solenoid 330 is energized to cause the soft-faced roller 326 to press the bill against the convex face of the magnetic head 244 and force the latter upwardly against its spring 246. The voltage variations set up in the head 244 by the magnetic ink of a genuine bill are amplified to produce two validating signals, the second of which can cause a connection to be made to a vending, change making, or other machine to be controlled by the currency detector. The solenoid 344 is now energized to release the front gate 370 which falls to close the bill slot, and operates a holding switch 362. The bill moves forward, operating switches in its path to condition the circuit and that of the associated vending &c. machine, and is finally ejected by the rapidly rotating rollers 314, 321. When a spurious bill is inserted, the two validating signals are not generated in the magnetic head 244, so that the front gate 370 is not moved down to close the billt slot in plate 36, the connections to the motor 188 are reversed, the belts 270, 272 are driven in the opposite direction to return the bill, and the roller 326 is moved away from the head 244. If a genuine bill with an attached withdrawing string &c. is inserted, the gate 370 cannot fall completely to close the switch 362, and the connections to the motor 188 are again reversed to cause the bill to be returned. Whenever the motor 188 reverses, the clutch in the drive to the shaft 162 slips, and the rollers 314, 321 are not driven reversely. In a modification (Figs. 21-24, not shown), an accepted bill is discharged by forcing it downwardly through slots in the platens 94, 50 by a sharp-edge plate which is oscillated vertically by a solenoid.