GB350270A - Improvements in fluid pressure operated brakes - Google Patents

Abstract

350,270. Fluid pressure brakes. BOSCH AKT.-GES., R., 4, Militarstrasse, Stuttgart, Germany. June 27, 1930, No. 19626. Convention date, June 27, 1929. [Class 103 (i).] Relates to control mechanism for fluid pressure brakes in which a lever is connected to the valve, the operating pedal or lever and an auxiliary piston subject to the brake cylinder pressure and including a spring or other variable resisting force in such a manner that the valve after being opened by the pedal is closed by the piston and the spring or other force reacts on the pedal to indicate the braking pressure. In an arrangement for a compressed air brake, Fig. 1, the lever c is connected to the valve h by the link and lever f, g, to the pedal a by a link h to a suspension link or lever n and to a piston m subject to the pressure in the pipe i<1> leading to the brake cylinder. A spring o is attached to the link n. The upper end of the lever has limited movement by means of an eye d, through which passes a fixed pin. When the pedal is depressed the lever c swings about pivot n<1>, the pressure valve is opened and the pressure established in the cylinder l of the piston m and the brake cylinder moves the piston m to the left, the lever c swinging back about the pivot b<1> and thus extending the spring o and closing the valve. The spring and the piston m react upon the pedal proportionally to the braking pressure. Upon further movement of the pedal this operation is repeated with a resulting increase in the braking pressure. When the pedal is returned the exhaust valve is similarly operated to reduce the braking pressure. The link n may be dispensed with and the spring o be connected directly to the lever c. The spring may be replaced by a cylinder the air in which is compressed by the movement of the lever c or as shown in Fig. 7 the variable resistance may be provided by a second cylinder s<1> connected as is the cylinder l to the pipe i leading to the brake cylinder. In this case a light spring t may be provided in the cylinder l so that the lever c first swings about the pivot m<1>. The application to vacuum brakes is also described.