Patent ID: 8251189

Claim:
Railway brake cylinder including: a body ( 11 ′; 11 ″; 111 ′; 211 ′); a piston ( 13 ′; 13 ″; 113 ′; 213 ′) mobile relative to the body ( 11 ′; 11 ″; 111 ′; 211 ′) to act on a brake linkage and delimiting with said body ( 11 ′; 11 ″; 111 ′; 211 ′) a pressure chamber ( 10 ′; 10 ″; 110 ′; 210 ′) adapted to be supplied by a pneumatic pressure agent source; an auxiliary actuating member ( 26 ′; 26 ″; 126 ′; 226 ′) mobile relative to said body ( 11 ′; 11 ″; 111 ′; 211 ′) and said piston ( 13 ′; 13 ″; 113 ′; 213 ′), said actuating member being mechanically connected to manual operating means to cause it to occupy: either a rest position in which it is away from said piston ( 13 ′; 13 ″; 113 ′; 213 ′) and so exerts no force on said piston ( 13 ′; 13 ″; 113 ′; 213 ′); or a pushing position in which it is in contact with said piston ( 13 ′; 13 ″; 113 ′; 213 ′) and exerts a mechanical force on it; characterized in that the brake cylinder includes: a first orifice ( 73 ′; 73 ″; 173 ′; 273 ′) in fluid communication with said chamber ( 10 ′; 10 ″; 110 ′; 210 ′); a second orifice ( 51 ′; 51 ″; 151 ′; 251 ′) in fluid communication with the atmosphere; and selective connection means ( 28 ′; 80 ″; 180 ′; 280 ′) between said first orifice ( 73 ′; 73 ″; 173 ′; 273 ′) and said second orifice ( 51 ′; 51 ″; 151 ′; 251 ′), said selective connection means ( 28 ′; 80 ″; 180 ′; 280 ′) being adapted to occupy: an isolating position in which said first orifice ( 73 ′; 73 ″; 173 ′; 273 ′) and said second orifice ( 51 ′; 51 ″; 151 ′; 251 ′) are isolated from each other; and a connecting position in which said first orifice ( 73 ′; 73 ″; 173 ′; 273 ′) and said second orifice ( 51 ′; 51 ″; 151 ′; 251 ′) are in fluid communication; said selective connecting means ( 28 ′; 80 ″; 180 ′; 280 ′) being mechanically connected to said auxiliary actuating member ( 26 ′; 26 ″; 126 ′; 226 ′) so that: when said auxiliary actuating member ( 26 ′; 26 ″; 126 ′; 226 ′) occupies said rest position, said selective connection means ( 28 ′, 29 ′; 80 ″; 180 ′; 280 ′) occupy said isolating position; and when said auxiliary actuating member ( 26 ′; 26 ″; 126 ′; 226 ′) occupies said pushing position, said selective connecting means ( 28 ′; 80 ″; 180 ′; 280 ′) occupy said connecting position.