GB334406A - Improvements in and relating to controlling devices for spring suspension systems of vehicles - Google Patents

Abstract

334,406. Zapaska, E. F. Dec. 7, 1928. [Convention date]. Vibration - dampers for spring suspensions of vehicles comprised in combination means for applying mechanical frictional resistance at an increasing rate to resist the movement together or apart of two vehicle members, and means for maintaining such frictional resistance at or near the maximum for a determined period after such members start the return movement. The mechanism is of the type comprising a brake drum and an internal friction band. A brake drum 1, Figs. 2 and 3, is secured to the vehicle frame 2 and contains a resilient friction band 5 adapted to be rotated by an oscillating lever 15 connected to the vehicle axle. On a central spindle 17 rotating with the band is loosely mounted an eccentric 30, around which is rotatably mounted the hub portion 41 of an application lever 40 having flexible arms 38, 39 engaging the end abutments 37 of the band 5. The arms 38, 39 are adjusted by screws 42, 142 to expand the band 5 and cause it to exert an initial pressure on the drum lining 9. For small oscillations, the band 5 rotates the eccentric 30 with it through a clutch 81, 32 of the fricton-disc type. On larger movement in a clockwise direction, as shown in Fig. 4, the bottom wall of a slot 33 in the eccentric 30 comes into contact with a stop pin 36 rigid with the drum, further rotation of the eccentric being thus prevented, and the further movement of the application lever 40 about the eccentric causes the arms 38, 39 to spread the abutments 37 and cause the band to apply increased frictional resistance at an accelerating rate. On the return movement, the eccentric 30 is first rotated with the band through the friction clutch, thus maintaining the maximum pressure of the band until the point when the stop pin 36 contacts with the upper wall of the slot 33, after which the frictional resistance decreases at an acelerating rate until the normal position of the vehicle parts is reached. A somewhat similar cycle occurs on movement in the opposite direction. The brake band has one end flexible and the other end rigid, in order to produce a servo action in one direction and thus increase the resistance on the rebound movement of the spring suspension. In the case of rapid movements, the action of the band is increased by centrifugal action.