GB317083A - - Google Patents

Abstract

317,083. Messier, G. L. R. J. Aug. 10, 1928, [Convention date]. Fluid-pressure; force-transmitting mechanism. -For regulating a fluid-pressure-actuated brake, particularly for aeroplane wheels, a number of parallel cylinders contain pistons which act upon one face of a common transmitting element, the other face pressing against a rod or roller to actuate the brake, and fluid is admitted only to the required number of cylinders. The brake pressure on the two sides of the machine may be varied by having separate groups of cylinders for actuating the two brakes, or a single group may be used and the pressure of the transmitting element variably distributed. The fluid pressure may be derived from a skid actuated pump. Fig. 6 shows a series of cylinders a<1>, a<2>, for example four, having plungers acting on a common element d sliding on a guide e', fluid pressure being admitted to the required number of cylinders and the remainder left open to exhaust. The element d acts through a roller q upon a floating lever r connected at its ends to the pistons of two hydraulic transmissions connected to the brakes on the two sides of the machine. The position of the roller q is varied by a connection to a, lever t which controls the rudder. Alternatively the element d may act through a hydraulic transmission or directly through a rod connected to the roller q through a swinging rod, and the lever r may apply the brakes through mechanical transmission. Fig. 3 shows a valve for admitting fluid to the four cylinders a<1>, a<2>, &c. Two pistons i<1>, i<2> on a common stem divide a cylinder h into three chambers h', h<2>, h<3>, the chamber h<2> being in communication with the pressure fluid through a pipe j, and the chamber h<3> being connected to exhaust through a pipe l. A passage i<*> in the valve stem connects the chambers h<1>, h<3>. By moving the valve stem, the required number of ports k<1> - - k<4>, connected to the cylinders, are put into communication with the chamber h<3>, the remainder being left open to exhaust through the passage i<*>. A spring plunger m engages notches n in the valve stem to retain it in any of its five positions. The pipe l may lead to a chamber having an airspace under low pressure so as to return any exhausted fluid to the pump actuated by the tail skid.