Abstract: A plasma generator including an excitation electrode and an opposite electrode confronting the excitation electrode such that plasma is generated upon impression of a high voltage between the excitation electrode and the opposite electrode. The plasma generator further includes granular material which is at least partially composed of dielectric grains and is provided between the excitation electrode and the opposite electrode.

Abstract: Apparatus for controlling the operation of a grinding system having a plurality of mills running in a parallel fashion, in which the operating condition of each mill is controlled such that a predetermined physical quantity, which changes dependent on the running condition, is equal to set values for the mills, and the set value for each mill is variably controlled so as to maximize the amount of pulverized material. The apparatus includes means for comparing a pulverizing amount F.sub.A per unit time of the mill under control with that F.sub.B of another mill, and controlling the set value for the mill under control so that a difference between the pulverizing amounts (F.sub.A -F.sub.B) is maximized while the set value for the other mill is fixed, whereby the set value of the mill under control is automatically optimized.

Abstract: Method and apparatus for automatically controlling a grinding mill in a mill arrangement which includes a grinding mill, raw material feed apparatus and a controller wherein one or more signals indicative of the condition of the mill are input to the controller and compared therein to a set point to generate an output signal based on the comparison and wherein the output signal is input to the raw material feed apparatus to adjust the rate at which raw material is fed into the grinding mill include an arrangement wherein the output signal of the controller is integrated for a predetermined time to obtain a first integrated quantity, the controller set point is then automatically varied a predetermined amount in a predetermined direction such that a second controller output signal is generated, the second controller output signal is then integrated for the predetermined time to obtain a second integrated quantity, the first and second integrated quantities are then compared, and the controller set point is the

Abstract: A classifier for particles includes a nozzle substantially in the shape of a rectangle in cross-section, through which a gas stream carrying particles to be separated flows. Finer particles exit through a slit in one side of the substantially rectangular nozzle. In alternative embodiments, more than one such slit may be provided in the nozzle, and/or the nozzle may be substantially angularly-shaped in cross-section.

Abstract: An impact flow meter for measuring a horizontal impact force produced by falling material has a frame and a sensing plate having a front surface and a spaced opposite back surface. A hanging device hangs the plate vertically on the frame thereby preventing material from adhering to the plate. A flow guide is mounted in the frame in front of the front surface of the plate at an inclination with the vertical for directing the falling material to the front surface of the plate whereby the plate is struck by the material. An impact force detector couples the back surface of the plate to the frame for measuring the horizontal impact force of the material.

Abstract: A powder-feeding method and apparatus according to which it is possible to provide one or a plurality of powder-feeding flows in which the powder is fed at a substantially constant rate which is of relatively small magnitude. A cone of powder is maintained substantially centrally of a disc which is rotated at a constant speed. A coarse scraper blade extends inwardly across the periphery of the disc into the cone of powder thereon substantially radially with respect to the disc so that the coarse scraper blade removes some powder on one side of the blade while leaving on the disc on the other side of the blade a layer of powder the depth of which is determined by the distance between the bottom edge of the coarse scraper blade and the top surface of the disc.