GB571761A - Improvements in or relating to ventilators - Google Patents

Abstract

571,761. Ventilators. HOLTON, F. C., and BISHOP, J. C. D. Nov. 5, 1943, Nos. 18362 and 21319. [Class 137] A ventilator comprises a spherical member mounted for angular movement within an annular housing and made up of disc-like parts providing an air passage of laterally spaced slots the effective area of which is controlled by movement of the sphere as a whole or of individual discs or interposed members in relation to one another. A single piece sphere 10, conveniently a plastic moulding, comprises discs 12 united by a web 13 and providing preferably tapered slots 11 which discharge in the direction set by the discs either converging jets at high velocity or diffusing jets at low, according to the position of the sphere within bearing rings 14. Rotation of the sphere on an axis in the plane both of the web 13 and the mounting wall 16 enables the volume of air to be varied or the ventilator to be completely closed. A modification, Fig. 5, comprises a number of plastic mouldings each consisting of a disc 21, a vane 22, part spherical wall 23 and a hub 25 through which passes a central pin, the discs being assembled surface to surface with the vanes projecting in opposite directions and a spring 26 fitted between adjacent hubs. By means of finger recesses 24 the discs may be separately adjusted to vary or close individually the air passages formed by the discs and vanes. The sphere is mounted within a ring 31 on pivots 29 projecting from a central disc 28, the ring being rotatably secured over the flange of a bracket 32. By rotating the assembly about the pivots the ventilator may be closed.