Control valve for air brake - with hand operated cam and spherical section bearing ring to prevent tipping

摘要

The hand control valve for the air brakes has a circular top (20) to the valve whose cam shaped control surface (16) operates on the control rod (26) of the valve. In order to move the control rod accurately, without any tipping due to uneven forces, the control surface has a spherical section groove into which is fitted a spherical section bearing ring (28). This ensures an even pressure between the cam and the control rod flange in all setting of the valve. The hand lever (22) and the various stages of the valve plungers have compression springs of different ratings between each.