Patent GB-615924-A (GB)
Title: Improvements in and relating to brakes
IPC: F16D51/56
Filed: 1946-05-07
Abstract: 615,924. Internal shoe brakes. FARKAS, P. May 7, 1946, Nos. 13842 and 13843. Convention dates, April 27, 1944 and Jan. 5, 1945. [Class 103 (i)] A brake comprises brake shoes each of which is formed of two or more separate elements, the adjacent ends of which are interconnected by a resiliently-loaded friction coupling device which allows relative angular movement of the elements to compensate for wear but holds the elements in their adjusted positions when the shoe is retracted from the drum. In one form, Figs. 1 and 2, a pair of shoes mounted on fixed pivots 1 and 2 are expanded by a cam 6 engaging rollers 7, 8 and retracted bysprings 3, 4, 9 and 10. Each shoe consists of two parts 13, 14 or 15, 16 secured together by fish plates 17, 18 which are yieldingly engaged with the adjacent end portions of the webs by bolts 19 provided with spring washers 22, 23 and passing through slots 11, 12 between the webs. The ends of the rims of the parts 13, 14 and 15, 16 are in contact so that if the whole of the lining does not engage the drum when the shoes are applied, the parts adjust themselves by pivotal movement about their line of contact, the adjustment being maintained when the shoes are retracted by the frictional grip between the webs and fish plates. The pivots 1, 2 may be replaced by a stop 82, Fig. 11 (not shown), having radial ends on which the shoes anchor. In a modification, Fig. 3, two-part shoes 2.5, 26 and 27, 28 are expanded by a wedge 43 engaging rollers 46, 47 and anchor in slots in plungers 33, 34 having conical ends enaged by a conical member 37 which may be screwed in and out to adjust the shoes. The " off " position of the shoes is determined by a stop 52. The spaced ends of the parts 25, 26 and 27, 28 are secured together by fish plates 55, 56 similar to those of Fig. 1. In further modifications, Figs. 8 and 9 (not shown), the shoes are mounted on a common pivot. In a second form, Fig. 5, lugs 59, 60 on the adjacent ends of shoe parts 61, 62 are interconnected by fish plates 63 which are clamped to the lugs by bolts 64, 65 provided with spring washers 66, 67 According to Fig. 12 (not shown), a pair of floating shoes each consisting of two parts having lugs interconnected as in Fig. 5 are expanded by a toggle, and one shoe applies the other through an adjustment device. In a further form, Fig. 14, lugs 143, 144 on the adjacent ends of shoe parts 139, 140 are secured together by fish plates 145 which are clamped against the lugs by a bolt 145 provided with spring washers. The ends of the lugs are formed with semi-circular recesses 143<SP>1</SP>, 1441 with which the bolt engages so that the parts pivot on the bolt. The arrangements shown in Figs. 14 and 5 may be used to contact the webs of two shoe parts, (see Figs. 6 and 13, not shown). Fig. 15 shows yet another form in which eyes 147<SP>1</SP>, 148<SP>1</SP> formed on or welded, or rivetted to the ends of shoe parts 147, 148 are interconnected by fish plates 149. The friction coupling device may comprise springs or rubber members acting directly or through a plate on the ends of the shoe parts and held in position by bolts or like means. The Specification as open to inspection under Sect. 91 also describes a brake shoe which is divided into two parts by a slot extending partially through the web, the parts of the web on either side of the slot being engaged by a friction coupling device. This subject-matter does not appear in the Specification as accepted.