GB1167250A - Resilient Coupling Device for Actuation of a Pressure Transformer Interposed in the Braking Circuit of a Self-Propelled Vehicle - Google Patents

Abstract

1,167,250. Vehicle braking systems; wire springs. SOC. ANON. FRANCAISE DU FERODO. 20 Dec., 1967 [20 Dec., 1966; 30 March, 1967], No. 57811/67. Headings F2F and F2S. A resilient linkage connected between a pressure-modifying valve in a vehicle braking system and a point on the chassis comprises two torsion bars of which the second algebraically adds its action to the first after a predetermined deflection of the first. Fig. 2 shows two torsion bars 28, 47 each bent at right angles at both ends, the one ends of each attached to a pressure-modifying valve 15 and the other ends to a stay 14 connected to the rear-axle case 11. The end 29 of the bar 28 passes through a rotatable core 30 (Fig. 4) and enters a barrel 27 which is solid with the plug 25 attached to the rod 23 of the pressure-modifying valve 15. The other end of the bar 28 (Fig. 2) is bent through two right angles and enters a U-shaped elastic member (40 in Fig. 3, not shown) to which is attached a coupling rod 38. The latter is yoked by a swivel joint to the stay 14 (details in Fig. 1, not shown). The second bar 28 is at one end 50 (Fig. 4) keyed on to the core 30 and at the other end is bent back on itself (Fig. 2) carrying a roller 54 bearing on the section 36 of the first bar. At the normal tare weight of the vehicle neither torsion bar is stressed. When the vehicle is loaded, the chassis drops relative to the axle 11 and the portion 36 of the bar 28 is deflected, turning the other end 29 to press the plug 25 (Fig. 4) downwards. This delays the instant at which the braking pressure in the rear-axle circuit becomes less than that at the front. If the dynamic load on the axle diminishes, the bar 28 rotates in the opposite direction, lifting the plug 25 and causing the rear-axle braking pressure to be reduced earlier. At the same time, the roller 54 (Fig. 4) causes the end 52 of the other bar to be deflected, so that the end 50 (Fig. 4) rotates the core 30 to apply an additional upward force on the plug 25. Modifications (Figs. 6-9, not shown).-In this case the bar 29 exerts only a downward force on the plug 25, deflection in the opposite sense merely lifting it away from the plug. The ends 36 and 52 of the bars are bent outwards in opposite directions and are attached to the axle 11 by swivel joints at spaced positions. The rod 52 is attached to its swivel joint via a plunger and sleeve so that it receives and passes on a deflection only for the direction of movement which aids the downward pressure on the plug 25.