GB359433A - Improvements in or relating to means for the coupling of trailers to road vehicles - Google Patents

Abstract

359,433. Tractor-trailer couplings. MASTERS, E. A., Hove To, South Wonston, Sutton Scotney, Hampshire. July 17, 1930, No. 21708. [Class 79 (iii).] In a vehicle coupling device of the kind in which a trailer draw-bar is pivotally connected to a U- shaped frame which is horizontally pivoted to the rear axle casing of the tractor vehicle, the closed end of the U-shaped frame is substantially semicircular and serves as a rail upon which rides a carriage, the draw-bar and the rail passing through the carriage in directions mutually at right-angles. The U-shaped frame comprises a continuous metal strip 12 shaped to pass under the end of the vehicle, with stiffening strips 13, a coupling pin cross-bar 15 and a transverse stay 14 or a pair of diagonal stays. Springs may be provided to take the weight of the frame. The draw-bar 17 passes through a carriage, Fig. 3, riding on the semicircular end of the frame, and is connected by a pivot pin 16 to the centre of the cross-bar 15, a slot 25 allowing relative endwise movement for automatic application of brakes. The cross-bar 15 may be a laminated spring or springs may be provided on the pivot pin to render the connection resilient in a vertical direction. The carriage comprises a pair of angle-ended plates 18 each bent to U-form to embrace the rail 11 and riding thereon by means of rollers on transverse connecting pins 19, 21. The draw-bar passes between the vertical arms 18 and between rollers on horizontal connecting pins 22, 24, the lower one of these being furnished with a winged nut 23 to facilitate disconnection. The free ends of the frame parts 12, 13 are spaced apart to engage lugs 28 on the axle casing being detachably connected thereto by pins 27. The lugs 28 may be welded or otherwise permanently secured to the axle casing but are preferably detachably connected thereto by chains as shown in Fig. 5, the lug being in the form of a plate with a re-entrant serrated edge 30 and having a halved-joint connection to a transverse plate 31 formed with a serrated edge 32 and a series of slots 33 in its curved back to allow alternative assemblages to fit differently shaped casings. The chain 34, pinned at one end to the plate, is passed round the axle and secured at the other end by a shackle 35 engaging a notch 37 in the plate, the connection being tightened by a screw 36. The Provisional Specification describes an arrangement wherein the chain is tightened by one or more bolts passing through the chain intermediately of its length and bearing upon the axle casing.