Patent GB-623254-A (GB)
Title: Improvements in braking apparatus
IPC: B60T15/02
Filed: 1947-04-21
Abstract: 623,254. Fluid-pressure-operated brakes. SVENSKA AKTIEBOLAGET BROMSREGULATOR, and CARLBOM, A. G. H. April 21, 1947, No. 10621. [Class 103 (i)] The fluid-pressure-operated valve device described in Specification 563,899 which is adapted to replace the plugcock provided in the triple valve of Westinghouse brake equipment for vehicles, for rendering operative or inoperative an additional brake cylinder automatically or by hand in accordance with the load of the vehicle, is simplified in construction. As shown, a pin 5 slidable in a bore in the member 1 which replaces the plug of the usual plug-cock is formed with a valve element 8 adapted to close the passage 7 in the member 1 and thus to cut off the connection of the additional cylinder C2 with the system through passages m, 11, 10, q. The pin 5 is formed also with an annular groove 9 adapted to register with ports 12 in the member 1 so as in "loaded" conditions to provide an additional supply passage for the main cylinder C1. The valve R which is operated by hand or automatically is adapted in "light" conditions to cut off passage L1 from passage L2 and in " load " conditions to connect these passages and thus the chamber 14 into which the end of pin 5 projects with the chamber 16<SP>1</SP> of a piston 17 which moves through a spring 18, a pin 21 formed with a valve 22 and an extension 23 arranged to move the pin 5. In " light " conditions the cylinder C2 is open to atmosphere by passages m, 11, 7, 30 and when in an application of the brakes, the slide valve S of the triple valve is moved to the position shown, pressure fluid is supplied from the reservoir A through passage a; the valve i of the "inshot" valve device, passages y, o to the main cylinder C1 until the pressure in chamber D of the "inshot" device is sufficient to depress the piston P, thus closing the valve i and leaving open only the restricted passage w. The pressure in the passage a also acts through passage 13 in chamber 14 on the end of the piston 5, thus holding it in the position shown so that the auxiliary cylinder C2 is connected to atmosphere by port 30. In " load " conditions the passage L1 being connected to passage L2 by valve R the pressure in chamber 14 is transmitted to chamber 161 of piston 17 which is thus moved to. the left hand to seat the valve 22 on passage 7, thus cutting off the cylinder C2 from the atmosphere port 30 and unseating the valve 8 by the pin 23 so that with the piston P of the "inshot" device in the lower position pressure fluid flows from chamber D through passages q, 10, 11, m to the cylinder C2. The edge 26 of piston 17 engages packing 28 in the left-hand position, to seal the chamber 16<SP>1</SP> from the port 30. The groove 9 in the pin 5 being in register with the ports 12, pressure fluid flows therethrough from the passage a to the passage O, thence to the cylinder C1 as well as through the passage w of the " inshot " device. When the triple valve S returns to release position, the cylinder C1 is exhausted through passages o, g. The cylinder C2 also is exhausted through the triple valve passage g through passages q, o, until the piston P returns to the upper position to connect the passage q to the atmosphere port Z.