Patent GB-743448-A (GB)
Title: Improvements in or relating to apparatus for reproducing sound recordings on tapes, wires or the like
IPC: G11B15/22
Filed: 1953-08-28
Abstract: 743,448. Magnetic reproducing apparatus. GLATT, M., and TILLER, D Aug. 30, 1954 [Aug. 28, 1953; Feb. 19, 1954], Nos. 23857/53 and 4983/54. Class 40(2) A tape reproducing apparatus is provided with means to select a desired portion of the tape and to wind or rewind the said tape to the beginning of the desired portion at a higher speed than the reproduction speed. The tape is wound from one reel to another by a rewind motor RW and take-up motor TU, respectively, and drawn past a reproducing head by capstan motor indicated CAPSTAN in the drawing. A 4-bank 8- point selector switch D enables any one of eight sections of the tape to be selected for reproduction and is associated with nine switch points 1 tn 9 which mav be contacted by a movable contact 12 whose position on a leadscrew 5 is related to the particular part of the tape passing the reproducer head. During a rest period between playings the contact 12 takes up a middle position between contacts 4 and 5. Relays B and C at this time are energized. while relay A is de-energized. To reproduce a desired portion, the switch D is set appropriately and the slot switch temporarily closed by the insertion of a coin, whereby relay A is energized and locked en by contact A6. The operation of relay A de-energizes relay B which de-energizes relay C by short-circuiting same. Let it be assumed firstly that one of the portions 1 to 4 has been selected. The closure of C2 starts motor PP which removes pressure pads from the tape and rotates switch. E to subsequently start rewind motor RW and rotate leadscrew 5 by the closure of switch contact E4. Motor RW rotates until contact 12 makes with contact 1. 2. 3 or 4 (according to the setting of switch D). and re-energizes relay C to stop motor RW. apply a braking DC to take-up motor TU, and maintain the drive of motor PP through E5. When E1 makes, CAPSTAN motor starts and E5 breaks so that motor PP stops. At the same time E2 makes so that motor TU drives and reproduction takes place. During reproduction contact 12 moves towards the next contact higher than the switch D is set for, and when contact is made relay A is de-energized by shortcircuiting same, which in. turn deenergizes relay C by open-circuiting, motor PP circuit is re-established via E6 to lift the tape pressure pads 'and the circuits of tne CAPSTAN and take-up motors are broken by E1 and E2. Motor PP subsequently re-establishes the circuit of motor TU via E3 to establish fast forward winding, until contact 12 is earthed by contact 10 to energize relay C to drive motor PP until E5 breaks and stops motor TU. At the same time a braking D.C. is applied to motor RW via E4. Subsequently E5 breaks and stops motor PP. When it is required to play a part of the recording requiring forward winding to reach the appropriate part of the tape, such as that represented by contacts 5, 6, 7 and 8, the operation of relay A causes the circuit of motor TU to be completed via D35, 36, 37 or 38, the circuit of motor PP to be completed via C2. and forward winding at fast speed to take place until 12 makes with contact 6, when relay C will be energized via D46, whereby motor PP is cut off and A.C. is applied to CAPSTAN motor and motor TU via E1 and E2. Reproduction then continues until contact 12 makes with contact 6, 7, 8 or 9 to de-energize relay A by shortcircuit via D25, 26, 27 or 28. This breaks the A.C. supply to the CAPSTAN motor and breaks the circuit of relay C to cause motor PP to rotate to close circuit of motor RW via E4. Rewinding thus takes place and motor PP will stop upon the opening E6. Eventually contact 12 makes with contact 11 to re-energize relay C and through it relay B to break the circuit of motor RW, close the circuit of motor TU through E3, and to rotate screw 5 in opposite direc. tion to move nut and contact 12 towards contact 10. A circuit is then established via E5 to rotate motor PP until E5 opens, during which time E3 breaks the supply to motor TU. At the same time a braking D.C. is applied to motor RW via E4.