Patent GB-597870-A (GB)
Title: Brake
IPC: F16D55/50
Filed: 1943-05-19
Abstract: 597,870. Brakes. SNEED, J. May 19, 1943, No. 7972. Convention date, Nov. 12, 1941. [Class 103 (i)] A brake particularly for vehicle wheels comprises main brake members rotatable with the member to be braked and movable axially towards each other to engage a non-rotatable member or members, as by links connecting them, when one of them is retarded by a pilot brake which may be of the internally expanding type or of the same type as the main brake, the main brake and the whole or part of the pilot brake being removable as a unit with the wheel. As shown in Figs. 1, 2, 3, the main brake comprises an annular member having a conical part 6 bolted at 16 to an aeroplane land-wheel, an annular conical disc 7 rotatable with the part 6 by engagement of projections 19 with slots 18 in an axial extension 13 of the part 6 and an inner member 8 rotatable with the members 6, 7 by a series of links 28 the inturned ends of which enter openings in the part 13 and in the member 8. The part 13 of member 6 supports the member 8. Non-rotatable members 9, 10 slidable on pins 27 projecting from the axle part 4 have conical parts 11 carrying friction lining disposed between the members 6, 7, 8. The members 6, 8 are urged away from each other by springs 40 abutting on sockets 13<1>, on member 6 and on an annular member 38 which is secured to member 8 and engages the inner ends of the links 28 to hold them in place. The normal clearance between the members 6, 7, 8, 11 is adjustable by a ring 35 rotatable on the member 8, by teeth 36 and having cam surfaces 39 engaging the links 28. For cooling, the pressure difference created by the travel of the wheel, between the forward and rear parts thereof adjacent the edge of the tyre rim causes air currents to enter the annular space between the brake and the rim at the rear as shown by the arrows 65 and to flow thence through radial passages 61 in the member 7 and out through the forward part of the annular space as shown by the arrows 66. The pilot brake comprises a drum 41 integral with the member 8 and a pair of shoes 42, the webs 47 of which are guided between arcuate bosses 45 formed on the member 10 and plates 46 fixed to the bosses and which engage near each end, anchor pins 48 on the bosses. A closure plate 59 is secured to the pins 48 by screws 60. The shoes are applied by a pair of cylinders disposed in the recesses between the ends of the bosses and connected at 54 to the ends of one shoe the pistons engaging the ends 56 of the other shoe. The shoes are adjusted by eccentrics 58 and when applied anchor respectively on a diametrically opposite pair of the pins 48. Retardation of the member 8 of the main brake by application of the shoes 42 causes the links 28 to incline from the axial direction and thus to force the member 8 towards the member 6 and the several members 6, 7, 8, 11 into frictional engagement. The pilot and main brake mechanism forms a unit which is mountable and demountable with the wheel In a modification, Fig. 8, the pilot brake comprises non-rotatable members 74, 69 arranged to grip a rotatable member 72, by the action of an inflatable tube 76 the members 72, 69 forming the inner part of the members 73, 68 of the main brake 67. The members 74, 77 between which the tube 76 is housed are mounted with the other non-rotatable friction members on fixed pins 78. The pilot brake members 69, 72 form with the main brake mechanism a unit which is mountable and demountable with the wheel.