GB312105A - Devices relating to the utilizing of coloured and opaque liquids in illumination - Google Patents

Abstract

312,105. Sharma, D. N. Feb. 13, 1928. Anti-dazzle screens.-A light screening device for use on a vehicle windscreen comprises a chamber adapted to be filled with and emptied of a coloured or opaque liquid by means of a source of pressure or vacuum under the control of a four-way tap. In the form shown in the Figure, liquid from a container w is injected into and withdrawn from a chamber b by means of a pressure or suction source v, such as the intake manifold of the engine, under the control of a four-way tap t. The source v is fitted with a cut-off tap i and the chamber b is fitted with cut-off valves a, c and is joined by a tube d to the container w. The tap t has four connections 1 - - 4 arranged so that when one pair (1, 3) is open, the other pair (2, 4) is closed, and in a neutral position all four connections are closed. Tubes e, h from the source v pass through connections 1, 4 to the chamber b and container w. Tubes f, g, open to the atmosphere, pass through connections 2, 3 to the tubes e, h, or directly to the chamber b and container w. The tubes d, h, may be fitted with removable flexible connections x to allow of the substitution of other containers with differently coloured or opaque liquids. The tap t may be of the rotatable body type, or one in which the body part is pushed in against the action of a spring. The chamber b may be formed by two flat or curved glass, or other transparent, plates separated by thin peripheral washers, it may be cast as a single unit, or it may be formed by bending thin glass tubes into any desired shape. Large chambers may be sub-divided into plurality of smaller chambers with separate inlets and outlets joined to the tubes leading to the four-way tap. The Provisional Specification also states that the source v may be a vacuum pump, and that the smaller chambers, into which a large chamber may be subdivided, may be fitted with a common inlet and outlet.