| 摘要 |
778,522. Brake cylinders. BOSCH GES., R. Jan. 18, 1956 [Jan. 22, 1955], No. 1669/56. Class 103 (1). The piston 5 of a brake cylinder has throttle bores 19 therein which are adapted to be closed by engagement with seals 21 on a flanged ring 17 welded to a guide tube 7 when pressure applied in chamber 4 moves the piston 5 to apply the brakes through a piston rod 14. On release of the brake pressure, the piston 5 moves back, together with ring 17 and guide tube 7 until the pressure in chamber 4 is in excess of that in chamber 11 by about 0.3 atmosphere whereupon the spring 18 separates piston 5 and ring 17 to allow equalisation of pressures on each side of the piston through the apertures. By using this type of construction, in combination with a non-return valve, not shown, at the non-pressure end of the cylinder, it is possible to prevent the entry of any air which may carry with it solid or liquid matter, during the return stroke of the piston. An embodiment for a longer type of brake cylinder is also described. |
