Patent GB-405307-A (GB)
Title: Improvements in or relating to electric switchgear
IPC: H02B11/18
Filed: 1932-07-26
Abstract: 405,307. Switchgear structures. GENERAL ELECTRIC CO., Ltd., Magnet House, Kingsway, London, GARRARD, C. C., and KEELEY, F. J., c/o General Electric Co., Witton, Birmingham. July 26, 1932, Nos. 21051 and 22056. [Class 38 (v).] A switchgear arrangement comprises a number of separate downwardly withdrawable switches or groups of switches, a structure 2 for supporting the switches, an overhead track 1 arranged below the structure and preferably supported thereby, and common raising and lowering means for the switches comprising a part supported by and movable along the said track, said part including tension members extending downwardly from the track and adapted to support the switches during the raising or lowering thereof. In the arrangement shown in Figs. 1 and 2, the portion of the raising and lowering gear movable along the track comprises a two-part bogie, each part consisting of a pair of blocks 11 carrying wheels 13, the blocks being connected together and spaced apart by a rod 12. The tension members comprise four threaded spindles 15 connected to the blocks 11 through universal joints 14. The spindles support a platform 16, with a central opening through which the switches can pass, and the platform is connected at its four corners to the spindles by means of four threaded sleeves 18. The sleeves are rotatably mounted in casings 19 secured to the platform 16, and are connected with each other through sprocket wheels and an endless chain, the sleeves being rotated, to raise or lower the platform, by means of a motor 17, which is geared to one of the sleeves. The switches are arranged in sets of three, only one of which is shown, and each set comprises a top plate 6, carrying the plugs 3, and three tanks 4, which are secured together. When it is desired to lower a set of switches, the platform 16 is moved beneath the set of switches, and members 32 on the plat. form are rotated to engage lugs 31 on the end switch tanks. The set of switches is then released so that it is supported by the members 32 and the platform is lowered to the desired position. When the switches are in the isolating position, the top plate 6 may be supported from rods 8 by stops 9 secured to the ends of the rods. The stops can be rotated to allow them to pass through slots in the top plate, and the switches can then be lowered on to a motor-driven transporting truck 37. This truck may be used to move the raising and lowering gear from one position to another by lowering the platform on to the truck and driving the latter. Correct positioning of the platform below a set of switches may be secured by providing, on the platform, holes adapted to engage downwardly extending guide rods secured to the switch supporting structure. The platform itself may serve as a transporting truck, in which case it is provided with wheels, and the sleeves by which it is mounted on the spindles 15 are split, the two halves being held together by a movable collar, so that the platform can be released from the spindles. In a modification, Fig.- 6, the spindles are replaced by chains 45, each of which passes round a pair of sprockets 46, 47, the upper sprockets serving as driving sprockets. In this modification, the members 32 engaging the lugs 31 on the tank 4 are in the form of sliding dogs.