Patent GB-415808-A (GB)
Title: Improvements in railway motor wagons
IPC: B61C11/00
Filed: 1933-03-06
Abstract: 415,808. Railway motor vehicles and small locomotives. CONSTANTINESCO, G., Oxen House, Torver, Coniston, Lancashire. March 6, 1933, Nos. 6768, 8422, and 10370. [Classes 79 (i), 79 (ii), 79 (iii), and 79 (v).] In railway vehicles and small locomotives of the kind having flanged running wheels and driving wheels which can be lowered and raised into and out of contact with the rails, the driving wheels are mounted on an auxiliary axle either (1) suspended from the vehicle and controlled by fluid-pressure means ; or (2) supported by an underframe articulated to the vehicle and provided with load-adjusting means, in either case the wheels on the auxiliary axle being pressed into contact with the rails to such a degree as to suit varying conditions, the flanged metal wheels retaining their guiding and supporting function. The driving wheels preferably have ordinary rubber solid or pneumatic tyres, but the tyres may be of fabric or of metal elastically supported ; the metal tyres could be flanged. When the rails are dry the pressure of the driving wheels thereon is light, but is increased when the rails are slippery and also on gradients. The variations of the pressure on the driving wheels may be effected mechanically, by fluid pressure, or automatically when the driving wheels slip. In the construction shown in Fig. 6, a railway wagon 1 running on the usual flanged wheels 2 is propelled by means of flangeless wheels 5 mounted on an underframe 4 pivoted at 9 to the wagon frame. The wheels 5 are driven by an engine 23 through a propeller shaft 15, the engine, axle 6 and wheels 5 being preferably standard motor vehicle parts. The underframe 4 is adjustably connected to the wagon frame by means of a bar 12 passed through suitable holes 11 in frame plates 10, the proportion of the wagon load borne by the driving wheels 5 depending on which set of holes is used. Lateral play of the underframe 4 may be checked by springs and a dash-pot. In the construction shown in Fig. 7, a power unit 23 is pivoted at 24 to the frame 1 and the pressure of the driving wheels 5 on the rails is adjusted by means of a fluid-pressure cylinder 21. The wagon may be reversed by lifting the driving wheels clear of the rails and pressing them against the flanged running wheels 2. This is preferably effected by a linkage which when operated in one direction presses the wheels 5 on the rails and when operated in the other direction presses them against the wheels 2. In one method of carrying this out, shown in Fig. 12, two sets of driving wheels 37, 38 driven in opposite directions are provided, one set being depressed as the other is elevated, so that both sets drive in each direction. Thus, when set 37 drives by engaging the rails, set 38 drives by engaging the wheels 2, and vice versa. In the means for preventing slip of the driving wheels shown in Fig. 16, a differential gear 45 has two members driven by chain gear 46 from a driving wheel 5 and the running wheels 2, the third member of the differential gear being coupled to a screw 47. When there is no wheel slip the screw 47 is stationary, but when the wheel 5 slips the screw rotates and rocks a lever 49 which applies pressure through a link 50 to the underframe 4 carrying the wheels 5 to stop the slipping. The differential gear may be driven by the propeller shaft 15 instead of by one of the wheels 5, or it may be driven by both wheels 5. A pump may be driven by the differential gear to vary the pressure on the wheels 5, or the differential device may comprise one or two pumps and may be combined with an electrical control. In all the devices for preventing slip the additional load on the driving wheels may be thereafter automatically reduced by degrees to a predetermined minimum, as by providing a difference in the rate of drive of the two elements of the differential gear 45, Fig. 16, or by allowing a small leak in a fluid-pressure device.