841,362. Track-fullness indicators for railway marshalling yards. WESTINGHOUSE AIR BRAKE CO. Feb. 7, 1957 [Feb. 7, 1956], No. 4206/57. Class 105. In a railway marshalling yard the state of fullness of a storage track (quarter full, half full, &c.) is shown by a visible indicator, a controlling device of which is actuated once each time a cut of cars passes the last points which are run over in proceeding to the particular storage track. A yard man is thus given information as to the fullness of any storage track and he then controls a trackway car-retarder (common to a group of tracks) so as to give an appropriate braking to the next succeeding cut. Fig. 1 shows a simple track layout and the combined Figs. 2a, 2b show in part the control apparatus for the portion comprising routes 1 to 3, this apparatus being one in which a number of routes can be set up and stored so as to be set up as required for a number of succeeding cuts of cars to be directed to the various storage tracks 1 ... 12. Assuming now that a cut has just run through and a succeeding route to track 3 is stored in a relay bank then a relay 1-3BSD will be waiting energized. Accordingly, front contact 14 of relay 1-3BSD will energize a storage transfer relay 1-3AST over back contact 15 of a storage detector relay 1-3ASD. This storage detector relay 1-3ASD will then be picked-up over a front contact 17 of the storage transfer relay 1-3AST and back contact 18 of a relay 1-3ASDPS and will close its stick contact 19. In known manner the points 1-3 will be set at reverse to direct the oncoming cut to track 3. The opening of contact 15 of storage detector relay 1-3ASD will meanwhile prevent relay AST being picked up again. When this cut drops the track relay 1-3TR of the detector section a relay 1-3ASDPS will be picked up over front contact 20 of storage detector relay 1-3ASD back contact 21 of a relay 1-3ASTPS and back contact 22 of detector section track relay 1-3TR. Relay 1-3ASDPS will then open its back contact 18 to de-energize relay 1-3ASD while its front contact 32 and contact 33 of points-at-reverse indicator relay 1-3RWP will energize a relay 1-3ASTPS. Front contact 52 of relay 1-3ASDPS and front contact 53 of points-to-reverse indicator relay 1-3RWP will actuate a counting device 3M1C1 to change over one of its armature contacts 1 : ... 10. An associated " tens " counting device 3M1C2 has similar contacts 1 ... 10 and these are so connected to the wires 66 that the " quarter," " half," " three-quarters," and " full " indicator lamps are lit when 20-39, 40-59, 60-79, and 80 (or more) cuts have entered the track. The " unit " counting contacts 1 ... 10 will not be energized until the relay 1-3ASDPS drops which occurs after relay 1-3ASD opens to contact 20. It should be noted that the relay 1-3ASTPS maintained energized over its stick contact 37 and back contact 36 of the detector section track relay, 1-3TR will prevent any second pick-up of the relay 1-3ASDPS by the cut of cars. If, however, the cut of cars is to be directed to storage track 1, then the sequence of pickings up of the storage transfer relay 1-3AST, of storage detector relay 1-3ASD, of relay 1-3ASDPS on entry of the cut into points detector section 1-3 with dropping of the track delay 1-3TR and the breaking of the stick circuits of relays 1-3AST is as before, but the points setting indicator relay now energized by the route set-up required is the relay 1-3NWP (not the relay 1-3RWP). Accordingly the relay 1-3ASTPS is not yet picked up and the relay 1-3ASD remains for the time being energized over its stick contact 19, wire 24, back contacts 25, 26 in parallel (of relays 1-2AST, 1-2ASD), wire 27, back contact 28 of track relay 1-3TR, and front contact 29 of points relay 1-3NWP. Relay 1-2AST thus becomes energized from back contact 31 of relay 1-3AST, front contact 32 of relay 1-3ASDPS, front contact 38 of points relay 1-3NWP, wire 39 and back contact 40 of relay 1-2ASD. Front contact 34 of relay 1-2AST thus applies potential to line 35 to pick-up relay 1-3ASTPS. The relay 1-2ASD is picked up over front contact 44 of relay 1-2AST and front contact 45 of detector section track relay 1-2TR; the consequent opening of parallel back contacts 25, 26 (of relays 1-2AST, 1-2ASD) breaks the stick circuit of relay 1-3ASD which drops and opens its front contact 20 to break the stick circuit of relay 1-3ASDPS. The relay 1-2AST at its contact 44 energizes relay 1-2ASD over front contact 45 of the detector track section relay 1-2TR. Relay 1-2ASD continues energized over a stick contact 46 and the track relay contact 45. Accordingly, when the track relay 1-2TR drops to close its back contact 47 the relay 1-2ASDPS becomes energized over a back contact 48 of the slow dropping relay 1-2ASD (de-energized by the opening of track relay front contact 45). When the cut leaves the points detectoi section 1-2 the relay 1-2ASDPS is de-energized by the opening of back content 47 of the track relay 1-2TR. The counting device 1M1C1 was actuated when the cut entered the detector track section 1-2 and closed back contact 56 of the track relay 1-2TR to apply potential over back contact 57 of relay 1-2ASDPS, front contact 58 of just de-energized relay 1-2ASD (before this relay dropped), and front contact 59 of points detector relay 1-2NWP. If the cut had been destined for storage track 2 the counting device 2M1C1 would have been actuated since the points detector relay contact then closed would have been 60 of relay 1-2RWP (not 59 of relay 1-2NWP). It will be noted that if a second control were received for relay 1-2ASD while the cut was still on the detector section, the relay 1-2ASD would be picked up by front contact 44 of relav 1-2AST and front contact 51 of relay 1-2ASDPS and held over stick contact 46 and front contact 51. However, the relay 1-2ASDPS can only be actuated once for each cut since it is held by a stick circuit until the detector section is vacated. A cancellation button is provided for each counting device whereby the operator can extinguish or reset the visual indicator to the appropriate indication when the storage tracks are emptied or only some cars removed. Specification 724,844 is referred to.