GB832921A - Improvements in or relating to electric lighting fittings - Google Patents

Abstract

832,921. Releasable fastenings. GENERAL ELECTRIC CO. Ltd. April 28, 1958 [Jan. 31, 1957], No. 3472/57. Class 44 Relates to electric lighting fittings of the kind having a frame 1 of bowl or trough form and arranged to fit mouth downwards into a recess in a room ceiling 3<SP>1</SP>, with a flange 24 provided round the mouth of the fitting bearing against the ceiling and with the fitting supported within the recess by the engagement of support members carried by the fitting with support means 3 arranged above the ceiling. According to the invention, each of the support members comprises a primary lever 4 pivotally mounted within the fitting frame for rotation towards or away from a side wall of the fitting and biased to a position of rest against the side wall, at which position a wedge-shaped projection 8 from the lever extends through an aperture 7 in the side wall, the projection having a substantially horizontal lower surface 9 and an upper surface 10 sloping downwards towards the lip of the projection, a secondary lever 12 pivoted on the primary lever 4 for rotation about a horizontal axis 11 and biased so as normally to rest against an upper stop 15 from which it is manually rotatable to cause an end of the lever to pass outwards and downwards through the aperture to an operative position in which at least part of its lower edge is level with or just above the lower edge of the primary lever projection, and clamping means for applying a force between the levers producing further downward rotation of the end of the secondary lever from its operative position, the arrangement being such that when the fitting is resting with the lower edges of the primary levers on supports, the fitting can be raised by such downward rotation of the secondary levers causing them to press against the supports, and the lengths of the secondary levers being such that after withdrawal of each support member, assembly into the fitting frame by inward rotation of the primary lever, the end of the secondary lever can be caused to abut against a lower stop which prevents any part of the assembly from swing back through the aperture. As shown, this stop is constituted by the lower edge of the aperture 7. The clamping means consists of a bolt 17 which engages through a slot 16 in the lever 14 with a threaded hole and the lever 4. The gravity bias on the levers may be replaced by spring bias means. Specification 830,826 is referred to.