Patent GB-517562-A (GB)
Title: Time-interval measuring device
IPC: G04F10/04
Filed: 1938-04-25
Abstract: 517,562. Indicating -apparatus for races. SHIPTON, E..April 25, 1938, No. 12401. [Class 106 (iv)] [Also in Group XVIII]  In a device for timing dog-races and embodying a field of lamps, illuminated strips, or mechanical elements which are illuminated or actuated in various combinations to indicate numbers representing for instance .seconds and hundredths of a second, high speed impulses are communicated to operate a chain of relays which mark positions on the contacts of selecting switches' so that when the impulses are stopped, a definite contact is marked corresponding to the last relay to operate, such contact being formed by a hunting switch which then stops and establishes the corresponding indicating circuit. The 50-cycle mains feed a transformer T the ends of the secondary being connected to two gas discharge relays V 1 , V 2 . The mid point of the secondary is connected to the cathodes of the tubes through a grid has battery and the output of each is fed through a series of relays. A condenserc is connected across the anodes. The current is switched automatically alternately through the chain'of relays in the anode circuits of relays V 1  V 2 , the one relay becoming reset as the other strikes. On discontinuing the applied' A.C., the last operated gas filled relay will not be extinguished but will continue its discharge. thereby locking up any relays which'may constitute the load in its anode circuit. The mains supply may be used for the heaters, grid control voltage, and anode potential. Across the H.T. supply leads is a near stabliliser S which in addition to the steadying effect co-operates with a relay N to ensure that the registering starts off at the "A" group of fast relays. The voltage under no load conditions is sufficient to cause the neon stabiliser to strike and operate relay N to close contact m to prepare the A group. In the anode circuit of each relay V 1 , V 2  is a series of high speed registering relays ACEGI and BDFHJ respectively. Such relay group prepares the circuit of the rest in recession, that is, A prepares B, B prepares C and finally J preoares A to repeat the cycle. At the start of a race, the primary of transformer T is closed. The relay V, then discharges one contact n to operate relays Ax, Ay, Az. Relay Ax operates first and closes contact ax to link contact n. Relays AY prepare the B group by closing contact ay. The relay AZ closes contact ab (not shown) to provide a marking' potential on the first contact on the bank of the 100th seconds. rotary switch R 1 . When the relay V 2  strike, V, is extinguished and the B group operated the A group being released. The V relays are slow while all X relays are fast so that contact bx is closed and B group locked before contact ay opens. The relays B 2  provide a marking contact on the second contact of the bank of rotary switch R. At the operation of the J group, the relay JW operates to step-up the 10th seconds rotary switch by one step. At each 10th step of the 10th second. rotary switch, the "units"  switch is stepped up one and so on. When the " stop " switch is operated, the last operated relay in series A to J locks up, the Z relay of this group providing a marking potential on the bank of the switch R 1 . A circuit is also closed whereby the switch R, is stepped around until it meets the contact marked by the relay. The relay M then operates to open the closing magnet of this switch. Simultaneously this relay may operate a contact to close a circuit and light up indicating, lamps 2. Specification 466,861, [Group XVIII], is referred to.