GB595764A - Improvements in or relating to electric or magnetic apparatus actuated by the passage of articles, such as bank-notes, through it - Google Patents

Abstract

595,764. Counting apparatus. KATZ, L. NAMENYI-, and FURZEHILL LABORATORIES, Ltd. Dec. 23, 1943, No. 1558/45. Divided out of 595,748. [Class 106 (i)] [Also in Group XXXVI] Articles such as banknotes are counted by registering electrical impulses produced by their passage through an impulse generator so arranged that impulses due to a group of more than one article combine to produce an impulse proportional to the number of articles in the group, which impulse correspondingly advances a registering device. In the apparatus shown, the arms of an A.C. bridge are formed by resistors 4, 5 and inductances 2, 3. The bridge is fed across one diagonal from an A.C. source 1, the other diagonal being connected to the input of an amplifier 6. The output of this amplifier is connected to a balanced modulator 7, which is also supplied with a signal input from the source 1. The output of the modulator is D.C. and is proportional to the out-of-balance voltage of the bridge and reverses in sign as the bridge output goes through the balance point. The output of the balanced modulator 7 is fed to a reactor valve 8 which is connected across the inductance arm 3 in such a manner as to tend to re-balance the bridge. The voltage derived at the input of the reactor valve 8 is nearly proportional to the original inductance change in the arm 3 and is supplied to an integrating device 9 which may comprise a resistance feeding into a condenser. Banknotes 12 containing metal strips are passed through the field of the inductance 3 and cause inductance changes proportional to the number of notes in each packet, thereby causing corresponding voltage changes at the input of the reactor valve 8. This voltage is integrated in the integrator 9, the voltage across the condenser of which is proportional to the number of notes passing together. The integrator condenser is arranged to be discharged whenever the signal input falls to zero by a discharging device 10. A counter 11, which is described in Specification 595,748, is operated by relays so that it discriminates between single, double and treble size impulses corresponding to the passage of one, two or three notes at a time.