Patent GB-1458272-A (GB)
Title: Brake control device for vehicles
IPC: B60T13/66
Filed: 1974-01-08
Abstract: 1458272 Multi-position brake controllers; valves KNORR-BREMSE GmbH 8 Jan 1974 [9 Jan 1973] 00913/74 Headings F2F and F2V A brake pressure level selector has an indicator movable between a number of braking level stages with responsive monitor means feeding a plurality of control valves via control lines connectible selectively in any one of a number of modes as a function of the level stage, and control means operated by the valves to control flow from a source to a brake cylinder; the indicator has a number of control paths corresponding to the control lines each path being equal in length or subtending equal angles and each path n in the sequence of paths comprising an alternating series of 2n sensing and non-sensing zones, an end control path having a sensing device and the other paths having pairs of sensing devices whereby the monitor means is connected to the sensing devices for selective operation by one or other of the pair of sensing devices associated with the next to end path dependent on whether the end path device is co-operating with a sensing or non-sensing zone, and one or other of the pair of devices with the next but one-to-end path dependent on which one of the devices of the next-to-end path is selected. An array of nozzles 3 issue jets of gas or liquid to corresponding receiving nozzles 4, these jets being allowed to enter the nozzles 4 through apertures in a disc, discs, a drum periphery, or a straight track, or are prevented from entering such that an array of signals are passed to a device 5 to actuate electrical circuitry of Fig. 7. Fig. 2 shows a rotatable drum with three tracks of apertures wherein the outer track 11 has twice the apertures of the next track 12 which has a similar relationship with the inner track 13. Here, the disc provides light steps for different signals. If further tracks are utilized, they follow the same progression. Alternative embodiments provide analogous constructions, e.g. three discs may be provided each having the same number of apertures wherein one disc is geared to the other to rotate through twice the angle thereof &c. Furthermore, a single track of a disc may be rotationally split into three 120 degree arcs. As shown in Fig. 2, the outer track 11 has a single nozzle 3.1, the next track 12 two nozzles 3.1, 3.3 respectively on either side of the nozzle 3.1, and the inner track 13 has two nozzles 3.4, 3.5 respectively on either side of the nozzles 3.2, 3.3. The single, outer track nozzle 3.1 may be in combination with an auxiliary nozzle, so that the aperture lengths of this track are shortened, providing a form of hysteresis for opposite rotations of the disc so that slight side to side movement at a transition between an aperture and the disc does not cause signal fluctuation. The location of an aperture for the nozzle 3.1 does not only provide a brake valve signal a, Fig. 7 but affects the signal transmission from the nozzles 3.2, 3.3 by means of an OR/NOR gate 14 providing signals to AND gates 15, 16 for those nozzles, the outputs thereof passing to a OR/NOR gate 19 for a second brake valve signal b. A similar control from these nozzles 3.2, 3.3 is exercised on the nozzles 3.4, 3.5 using the signals from the gate 19 to respective AND gates for the latter nozzles and an OR gate 20 for a third brake valve signal c. A flip-flop 21 may be used when the auxiliary nozzle is present to provide signal storing for the hysteresis effect. The disc/drum/track may be stationary and the nozzles may be moved as a unit.