Patent GB-318484-A (GB)
Title: Improvements in brake mechanism for vehicles
IPC: B60T7/20
Filed: 1929-06-07
Abstract: 318,484. Bosch Akt.-Ges., R. Sept. 3, 1928, [Convention date]. Fluid-pressure. - Vehicle brakes that are released by pressure fluid or vacuum and are applied for example by springs are provided with mechanical means for releasing the brakes such means being disconnected from the brake piston by further release movement of the piston when the pressure or vacuum is restored. Fig. 1 shows apparatus for a trailer vehicle comprising cylinders 7, 7<1> operating shafts 11, 11<1> connected to the front and rear brakes 12, 12<1> of the vehicle, application being effected by springs 10, 10<1>. Engine suction is normally maintained in the pipe 1<1> to maintain the brakes released. The device for taking off the brakes on a detached vehicle comprises cables 14, 14' extending from the shafts 11, 11<1> to a lazy-tongs mechanism the arms 16 of which are attached to a pair of half-nuts 17 arranged to engage a screwed shaft 18. The nuts 17 have handles 42, Fig. 2, and a spring 39 tends to separate them. They are guided by a fixed member 40. To release the brakes, the half-nuts are. engaged with the shaft 18 by gripping the handles 42 and the shaft is rotated to traverse the nuts. The tension in the cables 14, 14<1> due to the pressure of the springs holds the nuts in engagement with the shaft against the action of the spring 39 when the handles 42 are released. When the vacuum is restored in the cylinders 7, 7<1> the further inward movement of the pistons releases the tension in the cables and the nuts are disengaged from the shaft 18 thus unlocking the device and permitting the subsequent application of the brakes by the vacuum control. Specification 313,518 is referred to. The Specification as open to inspection under Sect. 91 (3) (a) also relates to a brake system in which brakes on a tractor vehicle are applied by pressure or vacuum, and those on a trailer by springs, and released by pressure or vacuum. The hand lever of a second brake on the tractor is arranged to bring the fluid-pressure controlled brakes on both tractor and trailer into operation. The control apparatus on the tractor comprises valves 2<1>, 2<11>, Fig. 3 (Cancelled), for the tractor and trailer brake cylinders actuated together by the levers 35, 36, connected by the link 25 to a lever 23. To the lever 23 are also connected the pedal 88 by the rod 24, the piston-rod 22 of the tractor brake cylinder, and a lever 27, one end of which is movable in an eye 26 in the lever 23. The rod 28 of the tractor brakes is connected to the lever 27. The valves 2<1>, 2<11> are thus controlled in known manner by the relative movement of the pedal 38 and the brake rods. A handlever 33 connected to an auxiliary brake on the tractor is connected by a spring 31 and a shaft 29 to the valve mechanism whereby the vacuumcontrolled brakes are applied on the tractor and trailer in addition to the auxiliary brake. A throttling device 34 is inserted in the pipe leading from the suction pipe 1 to the vessel 5 to prevent too much air from entering the brake pipe of the motor vehicle brakes on uncoupling the trailer. Cut-off and non-return valves 3, 4 are provided. This subject-matter does not appear in the Specification as accepted.