GB250245A - Electric fuse box with removable non-interchangeable fuse-carrying elements - Google Patents

Abstract

250,245. Compagnie Generate d'ElectricitÚ. March 31, 1925, [Convention date]. Fusible cut-outs. - The base 1 has an elevated part 5 forming a central space 6 and apertured at 7 to receive the contact 8 which is connected with a terminal 10. Above the part 5 is a contact plate 14 connected with a terminal 10<1> and secured by means of a screw 15 to the part 5. The plate 14 is perforated to receive any of a range of fuse cartridges, and the contact 8 is formed with a rim 11 beneath which engages a spring 12 pressing it upwards. Secured to the part 5 is a plate 2 which is apertured to receive the fuse of a particular rating, a series of plates 2 with varying apertures, Fig. 4, being provided. The fuse carrier comprises a cap 18 and cartridge 17 provided with lugs 19, 19<1> which vary in dimensions according to the fuse rating and the difference between the sizes being always greater than the permissible movement between one plate 2 and its cartridge so that a fuse of higher rating cannot be substituted. A cavity in the cartridge contains inert material 22, and the fuse wire 21, which is soldered at 23 to a metal casing 24 and to a sector 28 moving about a pin 27 which is riveted to the metal end 25 of the cartridge. The end 25 comprises two tongues 26. 26<1> located in grooves in the body of the cartridge and covering the upper faces of the lugs 19, 19'. Normally when the cartridge is ready in place the sector 28 is held by the fuse in a position at 180 degrees to its position of rest, and when the fuse blows the sector is rotated by a light spring 29 to its position of rest. The cap 18 has a glass disc 31 half of which is opaque and half transparent and the sector, which is preferably coloured so as to be observable at a distance, moves from under the transparent to under the opaque part when the fuse blows. To insert a cartridge into place it is necessary to get the lugs 19, 19' under the level of the plate 14 and then rotate the cartridge so that the spring 12 presses the metal-covered upper parts of the lugs against the plate 14.