GB1528058A - Automatic braking force regulators - Google Patents

Abstract

1528058 Load-responsive proportioning valves DAIMLER-BENZ AG 1 April 1976 [3 April 1975] 13195/76 Headings F2F and F2V An automatic brake pressure regulator 8, Fig. 2, varies brake pressure with load, the latter being represented by the variation of the distance between the regulator 8 mounted on the vehicle frame 9, Fig. 1, and the vehicle axles 1 and 2, the regulator including a control lever 6 which rotates in one direction with increasing load and in the opposite direction with decreasing load, the braking pressure being variable between a maximum corresponding to the regulator input pressure at full load and a predetermined minimum at no load, but if the lever 6 or its associated transmission linkage is severed, a spring in the regulator rotates control lever 6 beyond the minimum pressure position to result in a brake pressure above the minimum. In the regulator of Fig. 2, increasing input pressure at 11 causes downward movement of piston 13, eventually causing tappet 15 to lift valve member 14 from its seat to allow communication from inlet 11 to outlet 19 to the brake cylinders. A diaphragm 21 connects housing 22 with piston 13 and is progressively stretched over an entraining disc 24 of piston 13 as the latter moves downwards. When the maximum brake pressure for the particular load has been reached the piston 13 is returned to the initial position shown. The control lever 6 controls the position of the tappet 15 by rotating a cam 17 between a maximum pressure (fully loaded) position II and minimum (no load) position IV, the latter resulting in later opening of valve 14 in the stroke of piston 13 due to the depressed position of tappet 15. If the control lever 6 or its transmission linkage (parts 3, 5 and 7) is severed, a torsion spring (not shown) associated with shaft 27 rotates the shaft and cam, and hence lever 6, beyond position IV to a position V which causes the tappet 15 to rise to a position giving a braking pressure above the minimum and amounting to preferably 65% of the maximum.