GB645232A - Improvements in or relating to electric lighting fittings - Google Patents

Abstract

645,232. Fluorescent lamp fittings. GENERAL ELECTRIC CO., Ltd., and PHILLIPS, L. E. A. May 27, 1948, No. 14347. [Class 75(iv)] In a fluorescent lamp fitting the auxiliary gear (capacitor and choke) is housed in a ventilating duct through which cooling air is caused to flow by convection set up when the lamp is in operation. Fig. 1 shows a fitting having two fluorescent lamps 1, 2 lying in one horizontal plane wherein the choke 11 and capacitor 12 are disposed in the arms of a longitudinally extending V-shaped duct formed between the two lamps 1, 2 by two V-shaped members 3, 4, having ends 3b, 3c, and 4d, 4e, respectively which are bent horizontal and spacedly connected by pillars 6 to provide outlet spaces 7. The bottom of the V- shaped member 4 is formed flat and provided with a longitudinally extending gap 8 which may be covered with an ornamental perforated plate or wire mesh 17, a baffle plate 16 being disposed just above the gap. The choke 11 is connected to one arm of the member 3 and spaced therefrom by a heat transference shim 13, and the capacitor 12 is spacedly connected to the other arm of the member 3 by a washer 14. The top and bottom of the V-arms of the member 4 are provided with apertures 20 to allow some of the convection air to pass into the lamp chambers which are each enclosed by a fluted glass or like screen 9. The fitting is provided with end covers (not shown) and may be supported by screws 15 or suspended on a vertical member having projecting arms which engage slots in the V-shaped part of the member 3. In a fitting having a pair of lamps on each side of the duct, the member 3 also is formed with a flat bottom to its V-shaped part; the chokes being secured one to each arm of said V-shaped part and the capacitors being mounted one above the other to the flat bottom portion thereof. Fig. 4 shows an alternative arrangement where four lamps are disposed parallel to each other in one horizontal plane, two (such as 21, 22) on each side of the centre line 37 of the fitting. In this case a duct 28 is arranged between each pair of lamps 21 22 and is formed by two parallel longitudinally extending reflector members 24, 27 inclined at 60 degrees to the horizontal. The reflector member 24 is secured to a pair of suspension rods 26 via a pair of brackets 25, and the reflector member 27 is spacedly connected to the member 24. A lampholder mounting plate 23 carrying a startar switch 33 is disposed in the duct 28 so that the lampholders project one on each side through the reflector members 24, 27 respectively and the starter switch projects through an aperture in the member 27. A capacitor 31 and a choke 32 are mounted on the member 24 within the duct 28. The reflector member 27 is disposed so that apertures 35, 34 are provided at the top and bottom respectively to allow air to pass over the end lamp 21. A louvre 30 may be provided in the bottom of the enclosure containing the middle lamps 22.