Patent GB-101962-A (GB)
Title: Improvements in Pulverizing Mills.
IPC: B02C13/00
Filed: 1916-07-24
Abstract: 101.962. Raymond Bros. Impact Pulverizer Co., (Assignees of Lachmann, R. A., Senseman, W. B., and Raymond, A. W.). Oct. 23, 1915, [Convention date]. Impact pulverizers; feeding-devices for granular and like materials.-In impact pulverizers in which the material is drawn through the pulverizing-chamber by a current of air, the chamber is formed with a discharge-throat provided with a device which permits discharge of the fine material at the centre but retards an outward movement of the coarser material at the periphery As shown, the chamber 17 is formed with a conical discharge-throat 43 and a discharge-opening 45 and the device consists of arms 47 pivoted or rigidly secured to a hub 46 which is secured to a shaft 12. The hub is adjusted axially to increase or decrease the distance between the ends of the arms and the throat and thereby to increase or decrease the size of the discharged material. The beaters 38 are pivoted, or in some cases secured, to a disk 10 on the shaft 12, and may be adjusted for wear by providing a series of holes for the pivots 39 at different distances from the edge of the disk. The chamber is formed with an expanding conical part 41 surrounding the beaters and a contracting conical part 42 beyond the beaters. The shaft 12 carries fan blades 13 arranged in a casing 14 which communicates through a pipe 31 with a separator, the air being returned through a pipe 35. The chamber 17 consists of front and rear sections secured by bolts passing through lugs 20<a>, 21<a>. The material is placed in a hopper 26 provided with a feed-device 27. The Specification as open to inspection under Sect. 91 (3) (a) comprises also the following subject-matter : The hopper consists of a fixed casting 38, Fig. 3 (Cancelled), carried by a standard 39, a removable casting 40 secured by the lugs to similar lugs on the fixed casting, and a flared sheet-metal mouth. The front casting also rests upon a bracket and, by means of the lugs 58, 58', carries one end of the pulverizing- chamber. The feed-roller 26 is formed with longitudinal grooves 84 acting as pockets to feed forward the material. Transverse grooves may also be made in the roller, which works in contact with a pair of liners 85. A shoot 90 and opening 89 are preferably added just above the roller in order to enable the hopper to be emptied. The roller is carried on a shaft, which is retained in position, when the casting 40 is removed, by a spring-pressed sleeve engaging the half-bearing on the fixed casting. The roller is given intermittent movement by a pawl 110, Fig. 8 (Cancelied), and ratchet-wheel 104. The pawl may be held out of action by turning the weight 112 on to the tail-piece 113. To vary the throw of the pawl, a cam 118, controlled by the handle 120, is adjusted so as to engage the lug 119 and hold the pawl out of action during the desired amount of its active stroke. The cam is held in its set position by a spring-pressed latch 124 engaging in one of the grooves 123 corresponding to the desired position. The end of the fan chamber may be formed with an opening, over which is secured a device for admitting a regulatable amount of air. The device comprises a series of plates 157, Figs. 18 and 21 (Cancelled), having reversely projecting pins 158, 159, the pins 158 engaging in holes 58 in a movable ring 154, and the pins 159 in slots 151 in a fixed ring. By rotating the ring 154, the aperture for the passage of the air is varied as desired. Fig. 23 (Cancelled) shows a modified construction of feeding-device in which the front liner 160 is adjustably secured by the bolt 168, and the portion 165a of the casting is so shaped that, as the liner is moved downwards, a larger feed is obtained. The mill may be provided with a separator comprising a chamber covered by a pervious bag arranged over an apertured diaphragm, the dust from the mill entering the chamber below the diaphragm. This subjectmatter does not appear in the Specification as accepted.