Patent GB-191100899-A (GB)
Title: Improvements relating to Regulating Mechanism or Devices for Pneumatic Apparatus as applied to Milling, Grinding, and other Machinery.
IPC: B02C25/00
Filed: 1911-01-12
Granted: 1912-01-11
Abstract: 899. Simon, Ltd., H., and Simon, E. D. Jan. 12. Roller mills; mills and apparatus fitted with separating or sorting apparatus. - In pneumatic apparatus applied to purifiers, roller mills, &c., for milling purposes, and to separating, grinding, and like machinery in which the regulating-valve that controls the flow of air from a wind-trunk to a casing is connected with a compensating-valve which works oppositely to the regulating-valve and serves to admit air from another part so as to maintain the total amount of air constant, the valves are arranged so that changes in their effective areas are in the inverse ratio of the square roots of the pressure differences at the valves. The invention is shown as applied to a wind-trunk extending along the top of a purifier. The regulating and compensating valves a, b, Fig. 1, are connected by links c to a lever f, which is pivoted at g and carries a nut engaging with an adjusting-screw h. The slots c, d are of equal widths, but their lengths correspond with the inverse ratio of the square roots of the pressure differences between the interior of the purifier-casing and wind-trunk on the one hand, and the atmosphere and the wind-trunk on the other hand. The distances of the connexion points of the links e from the pivot g correspond with the relative lengths of the slots c, d; or the widths of the slots may be proportional to the inverse ratio of the square roots of the pressure differences, and the valves have equal movements. To prevent leakage of air, the lever f works through a sliding plate 14. Or the plates a, b may be operated by a rocking arm having at its outer end a head on a stem which can be screwed down so as to lock the arm in position. Fig. 2 shows the wind-trunk projecting above the wall k of the purifiercasing, and a single slide l to close and open the side apertures c, d which are of equal length but have their widths proportional to the inverse ratio of the square roots of the pressure differences. Fig. 4 shows a rotary valve r working within a cylindrical slotted casing v and having slots in its upper part which projects outside the casing, and slots t, u above and below the diaphragm s which work with the slots in the casing v. In another arrangement, flap valves connected by a link so that their movements are equal and opposite are used, the valve openings being of equal lengths and their widths proportional to the inverse ratio of the square roots of the pressure differences. Or rotary disk valves may be used. Arrangements may be provided for adjusting the relations between the openings of the regulating and compensating valves in the event of the pressure in the wind-trunk being changed; the pin g, Fig. 1, may be adjustable in a slot, or the widths of either or both of the slots c, d may be adjustable by means of lateral sliding plates, or the casing v, Fig. 4, may have an adjustable ring to cut off partly some of the openings therein, or a similar ring may be arranged in the valve.