Patent GB-393275-A (GB)
Abstract: 393,275. Controlling internal-combustion engine locomotives. CROMPTON, L., Winton, London Road, Harraby, Carlisle. Nov. 25, 1931, No. 32720. [Class 79 (v).] In power transmission mechanism for locomotives including duplicate internal-combustion engines differentially coupled to the driving axles. cam sequence reversing-gear is provided for each engine comprising an axially-displaceable camshaft, a plurality of cams for each valve and means for shifting the camshaft so that the appropriate series of cams may be rendered operative and either engine rotated in either direction. The invention is particularly applicable to a locomotive having the transmission system described in Specification 379,296 and shown in Fig. 3 and comprising two reversing internal-combustion engines 2, 3, each driving one of the sun-wheel members 5, 7 of a differential gear 10 the planet carrier of which drives the track wheels 11, so that (1) when both engines are running in opposite directions the locomotive is not driven, (2) when one engine is slowed or stopped the locomotive is driven by the other engine through the differential gear as a 2: 1 reducing gear, and (3) when both engines are running in the same direction at the same speed the locomotive is driven by both, the differential gear being idle. The engines are reversed and stopped by means of the gear shown in Figs. 8-10 in which the cam shaft 70 carries cams 75, 76 and a disc 74 for each rocker 71, the rockers being mounted eccentrically on a shaft 73 so that when this shaft is rotated the rockers are raised and the cam gear is ineffective. The rocker shaft carries a segmental pinion 79 and one member 80 of a Geneva stop device, the other member 81 being fixed to a gear wheel 78 formed as a nut on a screwed sleeve 77 which is freely mounted on the shaft 70 but cannot move axially thereon and is prevented from rotating in any suitable manner. When the shaft 73 is rotated the rockers are first lifted clear of the cams and then the pinion 79 rotates the gear wheel 78 on the screw 77 ; the screw is moved axially and carries the camshaft 70 with it so that the desired cam for forward, reverse, or light running is brought into operation. In the construction shown in Fig. 1 the engines 2, 3 are controlled by arms 21, 22 operated by hand levers 16, 18, the lever 16 carrying a floating lever 15 pivoted thereto at 26 and connected by links 19, 20 to the arms 21, 22 while the lever 18 is connected by a link 17 to the lower end of the floating lever. Thus, when the lever 18 is operated the floating lever 15 is rotated about its fulcrum and the arms 21, 22 are rotated in opposite directions ; when the lever 16 is operated the floating lever is moved bodily and, the arm 22 being held by the links 20, 17 and the lever 18, the arm 21 is rotated to an extent and in a direction determined by the movement of the lever 16. In the position shown the arms 21, 22 are vertical and both engines are stopped. By moving the lever 18 in a clockwise direction the arms are both rotated in the same direction and the two engines are started in opposite directions the locomotive remaining stationary. The locomotive brakes may be automatically applied when the levers are in the position described. To start the locomotive the lever 16 is moved in the clockwise direction sufficiently to return the arm 21 to the vertical position so that the engine 2 is stopped and the locomotive is driven by the engine 3 through the differential reducing gear. Further movement of the lever 16 in the same direction causes the arm 21 to be rotated still further in the counter-clockwise direction to a position in which the engine 2 is started in the same direction as the engine 3. The engine 2 now assists the engine 3 in driving the locomotive and when the speeds of the two engines are synchronized the locomotive is driven direct, the differential gear rotating bodily without any differential movement of its parts. The arm 21 acts on contacts 30 .. 33 respectively connected to cam reversal mechanism 34, a throttle control or governor 35, a starting mechanism 36, and a crankshaft brake 13 to hold the engine shaft stationary when the engine is not being used. The arm 22 acts on similar contacts for corresponding controls of the engine 3. Instead of the floating lever system a differential rack mechanism, Fig. 2, may be employed. In this construction the lever 18 is connected to a pinion 47 gearing with racks 45, 46, and the lever 16 is connected to the rack 45. The racks 45, 46 may be connected to arms 21, 22 as described in Fig. 1, but in the construction shown they are connected to racks 50, 51 operating pinions 52, 53, 54 actuating, e.g., camshaft reversing gear, a starting motor, and a crankshaft brake. Control of engine arms 21, 22 from different parts of a train may be effected as shown in Fig. 7, in which levers 16, 18 at one control station actuate hydraulic, pneumatic or electric telemotors 59, 60 from which the control operations are transmitted by lines 63, 64 to regulators 61, 62 operating the arms 21, 22. Similarly, levers 16a, 18a at another control station may actuate the regulators 61, 62 through telemotors 59a, 60a and lines 63a, 64a. The locomotive may be provided with reduction gear to be brought into use when it is to be employed on freight service.