Patent GB-221028-A (GB)
Title: Improvements in or relating to tramway and like vehicles
IPC: B61H7/02
Filed: 1923-06-18
Abstract: 221,028. Jones, W. J. June 18, 1923. Actuated or applied by relaxation of pull or by weight of vehicle; nipping-lever and like grip; back struts; locking by frictional detents; skid.- The backward movement of colliery &c. tramway vehicles on an incline is prevented, when the tractive force is relaxed as by breakage of the haulage cable, by slidably mounting the vehicle body on the wheeled under-framework, so that the brakes are applied by the longitudinal movement of the body with respect to the undercarriage. In the form shown in Fig. 1, the body a of the truck vehicle is free to slide on rollers c on the undercarriage b, and is guided in its movement by the engagement of rollers k with members on uprights i fixed to the undercarriage, by internally depending ears at the upper ends of the members i, and by a member m passing under a bridge-piece n, whilst its movement is limited by stops h on the body. Normally the haulage cable a<x> draws the body forward against springs o by the engagement of a, pin x with a slot y in the rod s, but if the cable breaks on an incline, the body moves rearwardly, and an incline p thereon engages a roller on an arm q, thus rotating a shaft g to apply the brakes d through the levers f, e. An extension l<1> of the member p passes under a cross-bar on the underframe to prevent upward movement of the body. The rearward movement of the body also rotates a shaft q<xx>, Fig. 4, by the engagement of a member e' with a bar c<1>, whereby a spike q<x> is caused to engage the track, but this movement may be prevented by moving the arm c<1> by hand, so that an aperture h<1> in it registers with an aperture g' in a crossbar f<1>. The spike is held in its normal position by a spring b<1> attached to an arm g<20> on the shaft q<xx>, an extension q<21> bearing against a strap b<2@0>. The longitudinal movement of the body may also be effected by the hand-lever w, and the brakes may be applied by hand without moving the body by disconnecting the two parts of the rod s by removing a hook bolt z. In a modification, Fig. 6, the body a of the passenger vehicle slides on rollers c as before, and is guided in its movement by the engagement of rollers t<1> carried on uprights u<1> with a member s<1> carried by a central longitudinal frame o<1> mounted on the underframework. In this form, the incline p actuates a skid brake z<1> against the resistance of a spring b<11>, and inclines w' apply blocks v<1> to the wheels, whilst jaws f<11>, Figs. 6 and 11, are caused to engage the rail against a spring h<11> by means of converging members g<11> carried by the body. Forward movement of the body raises the blocks v<1> by the engagement of inclines y<1> with inclines x<1> on the blocks. The registration of the apertures h<1>, g<1> of the members c<1>, f<1> is now controlled by a hand lever j<11>, Fig. 9, provided with an extension m<11> so engaging a slot n<xx> in a lever n<11> that when the apertures h<1>, g<1> register, a toe-piece o<11> passes under the spike q, whilst when the apertures are thrown out of register, the toe-piece moves clear of the spike. In order that the body may be drawn forward against a spring d only during the ascent of a gradient, a hollow member q<11> having screwthreaded engagement with the member p<1> of the frame o<1> is turned to compress the spring o against an abutment on a rod p<11> mounted on the body when ascending a gradient, and it is turned to release the spring o when descending a gradient, rearward movement of the body then being effected by passengers gripping handles r<1> on the frame o<1>.