GB1224648A - An improved brake for agricultural tractors - Google Patents

Abstract

1,224,648. Internal shoe drum brakes. ERNEST A. WEBB Ltd. 6 Aug., 1969 [7 June, 1968], No. 27183/68. Heading F2E. An internal shoe drum brake especially for an industrial tractor has a diametrically-split backing plate, each half of the plate carrying upstanding flanges which can be bolted together in pairs to secure the two halves together; the thus-assembled backing plate has a central hole of smaller diameter than that of the coupling flange on the half shaft of the tractor; the brake also comprises a ring, split diametrically, and having on each half an attachment plate adapted to be bolted to a square portion of the axle arm by bolts external to the axle arm, the ring and the backing plate being bolted together in use in a position such that the divisions in the ring and in the backing plate extend in different planes. The splitting of the backing plate obviates the need for applying it endwise over the coupling flange (which in this case is larger than the plate hole). To install the brake shown, the tractor wheel 15, Fig. 13, is removed. The upper half of the split ring 25, with the upper half of the backing plate 17 bolted to it, is disposed so that its attachment plate 26 lies on top of the (squaresection) inner portion 10 of the axle arm, Fig. 3. Similarly, the lower half of split ring 25, with the lower half of backing plate 17 bolted to it, is disposed so that its attachment plate 26 is underneath portion 10 of the axle arm. Securing bolts 28 are then applied. The attachment flanges 23 on the backing plate halves are bolted together, and a brake adjuster is fitted between the brake shoes (one shoe being shown at 18, Fig. 3). Then a brake drum 16 is fitted over wheel studs 14 protruding from a coupling flange 13 carried on the half shaft located in the hollow axle arm 10, 11, and the wheel 15 is replaced. The upper half of backing plate 17 carries the brake shoes, pivots and return springs 19, while the lower half carries spindle 24, return spring 22 and cam 20. The lower attachment plate 26 carries a lug 33 in which is journalled the spindle 34 to which is attached the brake arm 21. After a brake has been fitted to each of the two driving wheels a cranked and braced cross-bar 30 is connected to the two brake arms 21, a bracket (32), (Figs. 1 and 2, not shown) is attached to the centre of the crossbar 30 and a rod (31) pivoted to the end of hand brake lever (29) is attached by an adjustable threaded connection to the bracket (32).