Patent GB-379296-A (GB)
Title: Improvements in and relating to transmission mechanism
IPC: B61C9/10
Filed: 1931-05-23
Abstract: 379,296. Locomotive driving gear. CROMPTON, L., Winton, London Road, Harraby, Carlisle. May 23, 1931, No. 15296. [Classes 79 (i), 79 (ii), and 79 (v).] Variable-speed transmission mechanism for locomotives is characterized by the provision of duplicate reversible internal-combustion engines driving two shafts, these shafts being connected to a differential gear driving the locomotive so that alteration in the relative speeds of said shafts automatically effects alteration in the ratio of transmission between such shafts and the driving wheels of the locomotive. In the construction shown in Figs. 1 and 2, two transverse reversible internal-combustion engines 2, 3 respectively drive the sun pinions 13, 14 of a differential gear 10 through gear trains 4, 5 and 6, 7, the differential gear driving the track wheels 11 through helical gearing 17, 18. The engines are first started so as to run in opposite directions, thus revolving the planet pinions of the differential gear idly without driving the locomotive ; to start the locomotive one engine, say 2, is stopped and the other engine then drives the locomotive through the differential gear as a 2 : 1 reduction gear ; finally, the engine 2 is restarted in the same direction as the engine 3 and when both engines are rotating at the same speed the locomotive is driven directly without the differential gear acting as such. The two engines may be simultaneously controlled by means of two handlevers 56, 58, Fig. 7, fulcrummed at 64, 65, the lever 56 having a pivot at 66 for a floating lever 55 which is connected by a link 57 to the lever 58 and by links 59, 60 to arms 61, 62 respectively controlling the speed and direction of rotation of the engines 2, 3. In the position shown in Fig. 7, the arms 61, 62 are upright and both engines are stationary. By moving the upper part of the lever 58 to the right the arms 61, 62 are both rotated clockwise and the engines are started in opposite directions and by other movements of the levers 56, 58 the engines can be separately controlled. When the engines are started in opposite directions the locomotive brakes may be simultaneously operated, and when one engine is stopped a brake may be applied to its crank shaft, its valve gear may be put out of action and compressed air locked in its cylinders, or a compressed air starter motor, when such is provided, may be engaged to hold the engine stationary. The engines may be governor-controlled so as to run at any desired set speed. The engines may be arranged transversely or longitudinally of the locomotive, and their crank shafts may be parallel or co-axial ; in one construction the engines are arranged as a single unit having separate crank shafts and the differential gear is located in a housing integral with or secured to the common crank-case of the engine unit. A remote control system for the two engines may be employed as shown in Fig. 11, the enginecontrol arms 61, 62 being operated either by the hand-levers 56, 58 or 56a, 58a, these hand.levers controlling telemotors 69, 70 or 69a, 70a connected electrically, hydraulically, or pneumatically to regulators 71, 72 operating the control arms 61, 62.