GB990842A - Lamp fitting - Google Patents

Abstract

990,842. Turnbutton fastenings. E. LENZE, [trading as TRILUX-LENZE KOMM. GES.]. July 30, 1963 [Aug. 24, 1962], No. 30155/63. Heading E2A. [Also in Division F4] A lamp fitting comprises a transparent bowl with an inwardly offset vertical rim co-operating with a sealing strip on the underside of the lamp housing, and an externally operable rotatable clamp on the housing including an element for engagement under the shoulder formed by the inward offset disposition of the rim, the clamp element being sufficiently resiliently deflectable to allow for the maximum possible total variations of tolerance in the relative positions of the co-operating parts due to dimensional variations in them, the free end of the element engaging the underside of the shoulder having a sloping surface acting as a ramp when the clamp element is rotated into engagement with the underside of the shoulder. In the form shown, the bowl 4, Fig. 1, is held with its rim 6 in contact with a sealing strip 3 mounted on the inside of the housing 2 by a clamping device 7 having a shaped free end 8, e.g. one having a curved cross-section. The device 7 is secured to an operating lever 9 by flanges 14 in a saucer shaped depression in the lever, the depression resting in a circular opening 11 in the housing. In a modification, the depression may be formed in the device 7. In a further modification the housing may be bent inwardly around the opening 11 so that the device 7 has a less pronounced offset. In a further modification, the lever 20, Fig. 3, is not elastic but is carried by a bolt 21 on the housing, being pressed upwards by a spring 24 on the shaft of the bolt. Alternatively the lever may pivot on a horizontal pin, a torsion spring being provided for urging it into clamping position.