Patent GB-452546-A (GB)
Title: Improvements in or relating to the drying of grain
IPC: F26B17/12
Filed: 1935-11-14
Abstract: 452,546. Drying grain. DIENST, K., 3, Haydn-Strasse, Hildesheim, Germany. Nov. 14, 1935, No. 31492. [Class 34 (ii)] [See also Group I] Apparatus for drying grain comprises an upright hollow shaft having a grainsupplying chamber near the top, a grain-delivering chamber near the bottom, and an intermediate vacuum chamber in three sections communicating with each other, the upper section receiving the grain from the upper chamber, the intermediate section having heating means to dry the grain, and the lower section receiving continuously the dried grain, automatic means being provided for the supply of grain to, and discharge from, the vacuum chamber. In the construction shown in Fig. 1, the apparatus comprises a cylindrical shaft, an upper section 6 of which is adapted to receive the grain from a shoot 8, and to deliver it through a valvecontrolled opening 13 to a vacuum drying chamber which is in three sections, 5, 4, 2. The intermediate section 4 is provided with a radiator 17 and is connected to a vacuum conduit 10. The section 2 receives the dried grain and is adapted to discharge it through an opening 14 under control of a valve 16 which is connected to the valve 15 by a rod 35. The rod has at the top a screw-threaded part on which is mounted a worm gear adapted to be rotated by an electric motor 41, whereby the valves 15, 16 may be closed or opened. The motor is controlled by a reversing-switch connected to a pivoted plate 42 which is depressed, against the action of a weight 45, when there is sufficient grain in the section 5, thereby operating the motor 41 to close the valves 15, 16. The plate is lifted to reverse the switch, when the grain has left the part 5. The grain falls gradually through the radiator 17 which, as shown in Figs. 2 and 3, comprises a manifold 18, through which steam is supplied to pipes 20, preferably of oval cross-section, and a manifold 19 in which water of condensation is collected. The side walls 21, 22 of the radiator are perforated. Roof-shaped plates 23 are provided between the walls 21, 22 to provide for escape of moisture to the vacuum conduit 10. The bottom of the radiator comprises four hoppers 24 adapted to be entirely or partly closed or opened by gates 25 attached to rod 26, the position of which is adjustable by a hand wheel 27. In the construction shown in Fig. 6, each side of the vacuum chamber 2<1>, 4<1>, 5<1> is provided with a subsidiary chamber adapted to be connected to an evacuating pump to prevent entry of air into the vacuum chamber during the entry or discharge of grain. The chamber 50 is separated from the delivery chamber 6<1> and the vacuum chamber by partitions with valve-controlled openings. Similar arrangements exist with respect to the subsidiary chamber 51. The valves 15<1>, 54, 16<1>, 57 are operated by hydraulic means under the control of valves 79, 82. These valves are connected to each other by a pipe 84 and to a container 86 of pressure fluid, through a pipe 85. The valve 82 comprises a rotary plug 92, Fig. 9, adapted to be rotated through 90‹, the plug having two passages 93, 94 in different planes. The passage 93 is in the plane of pipes 83, 91 and the passage 94 in the plane of pipes 84, 81. The plug 92 is also formed with a groove 95. Pipes 96, 97, 98 are branched off' from pipes 91, 83, 84, respectively, to openings on the valve casing 82. The plug 92 is connected to a crank 100, Fig. 6, provided with a pin 101 engaging in a slot 102 in a rod 103 which is adapted to be moved longitudinally in one or other direction under the control of electromagnets 107, 108. A contact drum 109 adapted to be rotated by an electric motor 111 is provided with contacts co-operating with brushes which are connected to the windings of the electromagnets. Energization of the electromagnet 107 places the valve 82 in the position shown in Fig. 9 so that fluid under pressure from the supply pipe 91 is passed through pipes 83, 73 to the bottom of piston 63, whereby valve 54 is opened and grain flows from chamber 50 to the vacuum chamber 21, 41, 5<1>. Also pressure fluid flows through pipe 74 to the top of piston 64, to open valve 16<1> and permit discharge of the dried grain from the vacuum chamber. The fluid on the other side of pistons 63, 64 is delivered to the pressure fluid container 86 connected to a pump 88 which is driven by an electric motor 119 and supplies pressure fluid to the pipes 90, 91. Upon further rotary movement of the contact drum 109 electromagnet 108 is energized whereby the valve 82 is operated so that valves 54, 16<1> are closed. Valves 15<1>, 57 are similarly operated under the control of valve 79 which is controlled by means of a contact drum 118. The motors 111, 119 are controlled by a switch operated by a hinged plate 42<1>, the position of which is determined by the amount of grain in the portion 5<1> of the vacuum chamber. The motor 111 is associated with a clutch which upon supply of current to the motor permits only one revolution of the contact drums 109, 118. The valves 15<1>, 54, 16<1>, 57 may be replaced by cylindrical slide valves, as shown in Fig. 13. The rod 351 is provided with a slide 121 formed with passages 123 through which grain may flow from the chamber 6<2> to the chamber 50<1> when the slide is in its lowermost position. A cap 127 covers the passages 123 except when the slide is in this position. The slide at its bottom end forms passages 124 for flow of grain when the slide is elevated. A similar slide is provided at the bottom of the rod 35<1> for controlling delivery of grain from the vacuum chamber and the subsidiary chamber below.