Patent GB-419103-A (GB)
Title: Improvements in or relating to electrical timing apparatus
IPC: H01H7/14
Filed: 1933-07-24
Abstract: 419,103. Recording-apparatus. FLANAGAN, G. D., 11, Cliff Street, Essendon, Victoria, Australia. July 24, 1933, No. 20791. [A Specification was laid open to inspection under Sect. 91 of the Acts, Feb. 19, 1934.] [Class 106 (iv).] Electrochemical recording-apparatus comprises one or more pairs of electrodes bearing upon a sensitized surface and supplied with alternating or pulsating current so that the record, as shown in Fig. 2, comprises associated sets of dashes. When pulsating D.C. is used a transformer is included in the circuit. The record surface may be supported upon an insulating carrier, so that the current passing between the electrodes is largely confined to the surface of the record. The apparatus is shown in Fig. 4 arranged for recording the time a projectile takes to traverse a certain distance. The projectile in its passage first breaks a conductor 29 and so opens a short-circuit to allow A.C. of known frequency to be supplied to electrodes 8 bearing on a record disc 4 supported on a rotating table 2. The projectile breaks a conductor 30 at the end of the known distance to open the circuit. The number of dashes on the record is thus a measure of the time of flight. A soundrecording means is shown in Fig. 6, the microphone 46 being connected through an amplifier 41 to the electrodes 8. The electrodes are shown in Fig. 3 and comprise two nickel plates mounted on a glass spindle 18 and having upstanding stems 22 surrounded by springs which press the plates into contact with the record surface. A device for recording the fusing-time of a fuse 38 is shown in Fig. 5. Current is taken from a shunt 37 in the circuit containing the fuse 38 under test and is passed through a motor-driven interrupter 39 and an amplifier 41 to the electrodes 8 bearing on sensitized paper 4 on a rotating table 2. When a switch in the fuse circuit is closed, the electrodes make a series of marks on the paper 4 until the fuse blows. The speed of the interrupter is determined by stroboscopic means 36. Means for determining the period of operation of a camera shutter are shown in Fig. 7. Light from a lamp 48 passes through the shutter 49 and through a rotating disc 51 with equally-spaced holes in its periphery to a photo-electric cell 52 connected to the recording-apparatus 3. Commutator ripple on D.C. supplies may be recorded by passing the D.C. through a transformer, the secondary of which is connected via an amplifier to electrodes. An embodiment of the invention for timing competitors in a race is shown in Fig. 8. A pair of electrodes 8 is provided for each competitor and is supplied with A.C. at the commencement of the race by means connected with the starting pistol. The winning competitors break the circuits of the respective electrodes. Time markings are provided by electrodes 8<c> and the record strip is electrically clutched to the motor 61 shortly before the start of the race. The Specification as open to inspection under Sect. 91 describes also an apparatus in which, at the beginning of an operation to be timed, D.C. is supplied to an arm rotating in contact with a ring of fixed studs each connected to a point bearing on a fixed record surface. A series of dots is thus made on the surface, corresponding in number to the duration of the operation. This subject-matter does not appear in the Specification as accepted.