GB554408A - Improvements in and relating to brake systems - Google Patents

Abstract

554,408. Aircraft wheel brakes. GENERAL TIRE & RUBBER CO. Sept. 22, 1941, No. 12236 Convention date, Sept. 23, 1940. [Class 4] [Also in Group XXXIV] Aircraft landing wheels are provided each with a number of concentric brake drums to which cooperating friction members may be selectively applied to vary the braking effect on each wheel. The brakes may be applied by a hydraulic master cylinder which can be put into communication with the several brake units by a selecting valve. The end walls 70, 71 of a wheel are formed each with a pair of concentric flanges 73, 74 to which steel drums 80 are secured, cooling channels 82 open at both ends being provided between the drums and flanges. Each brake unit may be of the construction described in Specification 550,339, [Group XXXIV], comprising a number of shoes 98 arranged to be applied to the drum by an inflatable annular tube disposed with the shoes in a channel-section support 94 secured to a flange 88 of a torque taking member 83 bolted to a sleeve 85 on the fixed wheel axle 68. The shoes have pins 99 that extend through radial slots in the support 94. Corresponding brake units 1a-4a, 1b-4b of a pair of wheels A, B, Fig. 1, are connected by pipes 8-11 which are connected to a selecting valve V to which also is connected a hydraulic master cylinder 17 by pipe 6. The valve V mounted on the instrument panel 38 of the aircraft comprises a conical plug 28 having a handle 40 and passages 47-51, the passages 47, 48, 49, 51 having circumferential extensions 54 - - 57 of decreasing length. Liquid that may leak past the plug 28 is discharged by a flange 107 and a drain passage 108. In the position shown, upon operation of the master cylinder all the brakes 1a-4a, 1b-4b, are applied but by turning the plug clockwise the pipes 10, 11, 9 are successively cut off and in the final position only pipe 8 and the pair of brakes 1a, 1b are supplied. Release of the brakes, if applied when the corresponding pipe is cut off is effected by axial passages 59 which lead from the radial passages 46 of the casing to radial passages 62 in the plug 28 thence to a pipe 63 connected to the reservoir 24 which maintains the hydraulic system filled.