GB742943A - Improvements relating to transmission means for operating vehicle brakes - Google Patents

Abstract

742,943. Transmitting-mechanism for brakes. JENSEN MOTORS, Ltd. March 18, 1954 [March 19, 1953], No. 7552/53. Class 103 (1). In a transmission arrangement for operating the front and rear wheel brakes of a vehicle, a balancing member is connected to the front and rear wheel brakes at spaced positions and a sliding connection is provided with an input element connected to the pedal or like operator's control such that as the input force applied increases, an increased proportion of that force is applied to the front wheel brakes. In the embodiment illustrated in Fig. 1, master cylinders 12 and 13 are secured on the forward side of the bulkhead structure provided between the engine compartment and the interior of the body of the vehicle. The master cylinders 12 and 13 are operated by piston-rods 17, 16 respectively to supply hydraulic fluid to the rear wheel brakes via pipe 11 and to the front wheel brakes via pipe 10 respectively. The extremities of the piston-rods 16 and 17 are pivotally secured to the ends of a balancing link 18 which is provided with a slot 25 in which a roller pin 26, secured to one end of a push-rod 19, operates. The other end of the push-rod 19 is pivotally secured to an intermediate lever 23 which is, in turn, pivoted to a fixed part of the vehicle 14 at 24. Also pivoted to the intermediate lever 23 about its mid-point is a link 22 which is pivoted at its other end to a dependent lever 20, pivoted at 21, and carrying at its other end a brake-operating pedal 15. In operation, the roller pin 26 is retained, in the position illustrated, at the upper end of the slot 25 which lies mid-way between the points of pivotal connection of the balancing link 18 with the pistonrods 16, 17, by a spring 27 so that initially approximately equal thrusts are transmitted to the piston-rods 16 and 17. Increasing thrust on the push-rod 19 will drive the roller pin downwardly in the slot against the action of the spring 27 to bring the point of connection nearer to the lower piston-rod 17, thus increasing the proportion of the thrust transmitted to the front brakes compared with that transmitted to the rear brakes. Another embodiment of the invention is described for use with master cylinders which are situated under the floor of the vehicle and the invention may equally be applied to mechanically-operated brakes.