GB733855A - Improvements relating to ventilators, primarily for vehicles - Google Patents

Abstract

733,855. Ventilators. ROEVAC AIR EXTRACTORS (1952), Ltd. July 31, 1952 [July 31, 1951], No. 18058/51. Class 137. A vehicle ventilator comprises a base 1, forming part of a vehicle wall or roof, having an aperture 2 therein, an upstanding flange 3 around the aperture 2, and a hood 5 hinged to the base and adapted to be held in a closed position or in a number of open positions, so that with the hood closed a limited air extraction is obtained compared with a substantial air extraction when the hood is open. As shown, the hood 5 is rectangular in plan and partly streamlined in longitudinal section and is operated by a ring 6 welded to its under side. The front wall of the hood is formed with a series of upwardly directed louvres 11 and the flange 3 has an upward extension 12. The base has a pair of inclined lugs 7 upstanding therefrom, each of which has a series of depressions 7a arranged in a curved path to be engaged by spring-pressed plungers carried in housings 8 on the inner side walls of the hood 5. The lugs 7 pass through slots in a pair of brackets 9 in which the housings 8 are placed, the brackets being strengthened by stays 10. Bent-over portions 7b of the lugs form stops. In a modification a toggle device is arranged which passes over a dead-centre position between the open and closed positions of the hood. In either construction a deflector or aerofoil may be provided on the base at the forward end having an upwardly-inclined forward part and a vertical rear wall spaced from a narrow slot in the front of the hood. In a further form the hood is hinged at the rear of the base instead of at the front so that when the hood is open a rapid entry of air results. Specification 535,109 is referred to.