GB264163A - Improvements in or relating to pneumatic conveyor apparatus - Google Patents

Abstract

264,163. Zimmermann, C. F. Jan. 11, 1926, [Convention date]. Pneumatic conveyers. - Loose or powdered materials, such as ashes from a banli of furnaces 20, Fig. 1, are drawn through a conduit 21 into a collecting chamber 26 provided with outlet valves 29, 30 for the ashes &c., and with a separator 42 and steam-jet ejector or other suction-device 65. The ashes accumulate upon the outlet valves until the latter open automatically under control by an oil cataract cylinder 71. The valves are closed automatically by a steam cylinder 72, and in a modification the valves 30 are dispensed with and the steam cylinder is double-acting and assists in the opening of the valves 29. The collecting chamber 26 is rectangular in plan and is connected with the conduit 21 by a steeply tapered inlet 27 so that the velocity of the current is reduced gradually and the bulk of the material is deposited. The separating chamber 42, Fig. 2, comprises a rectangular framework 48 with louvres 51 at each side formed by the flanges of angle bars 49, The framework is surrounded by screws 53. Water is sprayed on to the screens from the pipe 56, and drains away at 59. The framework is closed at the top by a plate 63 and the suction outlet is connected to the outer casing 42, The collecting chamber 26 is provided with two pairs of flap valves 29, 30, Fig. 1, hinged at 31, 31<1>, and closing against bars 32. The space A between the valves is connected by a pipe 136 with the air separating chamber. The valves are operated by lever arms 36, 36', Fig. 2, connected by links 40, 40<1> with lost motion so that the upper valves can open before the lower but close with them. The arms 36 are connected with a collar 37 supported on an actuating rod 39 by a spring 50. The rod 39 carries a piston in the steam cylinder 72, and a piston in the oil cylinder 71. The cylinder 71, shown enlarged in Fig. 4, is completely filled with oil, and is provided with a main by-pass passage 81 controlled by ports overrun by the piston, and with a small bypass 88 leading from a space 87 above the piston. This by-pass is regulated by a needle valve 89 or by a pressure-responsive valve, and a non-return valve is provided at 91. As the ashes collect upon the valves 29, the piston 76 is drawn downwards at a rate determined by the valve 89, until it uncovers the ports 95. The piston then falls rapidly, and the valves 29 are fully opened. The valves 30 are then free to open as soon as the pressure in the collecting chamber has reached atmospheric. As the piston 76 reaches the bottom of its stroke a tappet in the rod 39 moves a discvalve in the casing 78, Fig. 2, to admit steam to the lower end of the cylinder 72 and raise the rod 89 to close the valves 29, 30. During the upward movement, the piston 76, the oil passes freely through the check-valve 91. At the end of the upstroke, the tappet on the rod 39 actuates the valve 78 to cut off the steam and open the cylinder 72 to exhaust. When the cylinder 72 is made doubleacting, an additional disc valve and tappet mechanism are provided. The Specification as open to inspection under Sect. 91 (3) (a) comprises also a slide valve in the connecting pipes 136 which is closed automatically when the valves 29 are open. This subject-matter does not appear in the Specification as accepted.