Patent GB-864915-A (GB)
Title: Improvements in or relating to apparatus for recording the time of occurrence of events
Filed: 1958-11-19
Abstract: 864,915. Recording-apparatus. FISCHER & PORTER CO. Nov. 19, 1958 [Nov. 19, 1957], No. 37278/58. Class 106 (4). Apparatus for recording on a tape T the identity, sequence and time of occurrence of a series of events which happen in rapid succession (e.g. spaced by milliseconds), comprises coding circuits 130 receiving input signals from terminals 128 and providing, for an input from each terminal- 128, a combination of simultaneous output signals identifying the input signal (e.g. the combination of an output signal on each of the lines 134, 140, 144, 150, 152 to represent the number 396 allotted to the particular terminal 128 shown), circuits receiving each combination to record it on the tape T and time marks 92, 119 on the tape to identify the time of recording the combination. . Tape drive.-Tape motion starts with the occurrence of the first event of a series, continues while the events occur in rapid sequence and stops only after say one fifth of a second after the last event of such sequence. Quick starting is facilitated by forming a loop of the tape T over a roller on a pivoted arm which takes the brake off the take-up roll as soon as the drive roll begins to take up the slack in the loop and applies the brake as soon as the tape slackens when the drive stops. Time printing.-As soon as an event occurs, the date and time are printed, Fig. 7, ref. 92, and an ink ribbon is advanced. The time and date wheels are driven by a synchronous motor, the lowest denominational wheel being driven continuously and being calibrated every five thousandths of a minute. Printing from this wheel is shown at 96 and 99 and an arrow printed from a fixed slug facilitates interpolation. Strokes printed in the time channel 119 every sixtieth of a second during a sequence enables the time of occurrence of each event to be read. Recording events.-The events are recorded by chisel points on pivoted arms adapted to print through the inked ribbon, elongated marks on the tape T in eleven channels, ten for coding the point where the event occurs and the eleventh, designated ON, indicating " ON " by a mark and " OFF " by its absence, the precise significance of the labels " ON," " OFF " being predetermined. The tape is pre-printed at intervals with the legends 105. Electric circuits.-The coding and operating circuits are shown in Fig. 4, with particular reference to the position relay 396. Energization of the relay 126 provides terminal 129 with a positive signal, de-energization with a negative one, the former being regarded as an " ON " pulse and the latter as an " OFF " pulse. Isolating neon bulbs e.g. 166 fire and pass on a positive or negative signal respectively. Isolating diodes e.g. 248 ensure that only a positive signal can energize the primary of transformer 252 and so cause printing in the " ON " channel. On the other hand, either positive or negative signals to the primaries of the other transformers e.g. 182 cause printing in appropriate coding channels, the secondary currents produced being rectified 184 to pass only negative pulses which, amplified by transistor stages, e.g. 186, 188, feed relay 190 and make capacitor 194 discharge through the electromagnet 202 to produce a sharp short stroke of the corresponding hammer to print on the tape T. The similar circuit corresponding to zero hundreds, which is not printed, is used to control the time printer, ribbon feed, drive motor 4 and time track marking. This control circuit includes an RC circuit 286, 302 with time constant one fifth second to keep the motor 4 driving for one fifth second after each event pulse. The motor is of a high starting torque type capable of coming up to full speed within one cycle, it runs so long as relay 304 is energized and when the relay 304 is de-energized a heavy direct current, produced by the charged capacitor 346, flowing through a winding 338, quickly brings the motor to rest.