Patent GB-495679-A (GB)
Title: Improvements in or relating to centrifugal apparatus
IPC: B04B13/00
Filed: 1938-02-03
Abstract: 495,679. Centrifugal machines. WESTERN STATES MACHINE CO. Feb. 3, 1938, No. 3412. Convention date, Feb. 5, 1937. [Class 23] A centrifugal machine, particularly for the treatment of sugar, has a suspended bowl 11 of the filter type driven at high or low speeds through separate clutches controlled by means operable by a common actuating member. The bowl is preferably of the type described in Specification 440,589 and it is accelerated quickly as described in Specification 489,257. The main clutch for high speed operation is constructed as described in Specification 392,819, [Group XXIV], and the bowl is provided with a valve to control the discharge path of separated liquid and washing water as described in Specification 417,782. The various mechanisms controlling the operations may be controlled individually, or be controlled generally by the operation of the hand wheel 80, or the proper sequence of operations may be ensured by means of timing control mechanism 175. The main driving shaft 63 carries a sleeve 62 with a bevel gear wheel 61 in mesh with a pinion 60 at the top 42 of the bowl shaft 12. The sleeve is also connected to the drum 64 of the main clutch, which may be of the type described in Specification 392,819, [Group XXIV], and has friction shoes 70 rotating with the shaft 63 ; they are brought into operation by a sliding collar under the control of a forked arm 73 operated from a pinion 78, Fig. 7, at the rear end of .the shaft 79 of the hand wheel 80. The bowl spindle carries a brake drum 41 and its semi-cylindrical shoes 44, 45 are operated through a linkage 55, 54, 53, 52, 51 from a rotatable sleeve 56 on the hand-wheel shaft 79. This sleeve carries a disc 90 with an adjustable pin 91 engaging a cam 93 with an abutment against which the pin is held by a spring 95 when the clutch shoes 70 are out of engagement with the drum 64 and the brake shoes are applied to the brake drum 41. This arrangement thus effects disconnection of the main driving means when the brake is " on." The brake mechanism is also locked in the " off " position by the detent 103 engaging an abutment 102 on a sector at the end of the arm 99, Fig. 13, connected with the links 53, 54. While this lock holds, the hand wheel 80 can be moved to and from the clutch-engaging position independently of the spring 95 and other parts of the brake actuating mechanism. The detent 103 can be released by the timing mechanism or by manual operation of the handle 105. The clutch for low speed has an outer conical part 122 connected with the shaft 63 by chain and toothed gearing, and an inner member 128 movable axially on the shaft 129 to which the part 122 is keyed. The member 128 is attached to a pinion 131 able to mesh with a ring gear 132 on the outside of the main clutch drum 64. The clutch part 128 is operated by a fork 134 on the shaft 136 rocked by an arm 142 which is connected by a resilient connection 149 to the rod 148 and an arm 150 associated with the yoke 151 behind the hand wheel 80. The bowl is provided with a spraying nozzle 36, and adischarge mechanism 37 for deposited solids, while the bowl casing has two annular troughs 14, 15 controlled by a valve plate 19. With the plate in the position shown in Fig. 1, liquid discharged from the bowl passes to the trough 14, but when washing fluid is supplied the plate 19 is lifted by the bail 20 so that the fluid streams down the casing wall to the trough 15. When the parts are in the position shown in Fig. 6, the brake is applied and both clutches are inoperative, and operations are started by an attendant rotating the wheel 80 in a clockwise direction. This causes the valve plate 19 to be locked in the position shown in Fig. 1, moves the brake to the " off " position where it is locked by the detent 103, and throws in the main clutch so that the bowl runs at a high speed for treatment of the substance supplied. The valve plate 19 may be operated when required by the hand lever 112, and the detent 103 may be released by the hand lever 105 to apply the brakes before the hand wheel 80 is operated to throw in the slow speed clutch. To operate this clutch the hand wheel 80 is depressed against the spring 159 to insert the cam member 157 into the space 156 in the yoke 151, and the wheel is then turned in a counterclockwise direction. The manual release of the locking means on the valve plate 19 and the brake mechanism may be replaced by timing mechanism operation. The timing mechanism 175 consists of discs 184, 185, 186 carrying projecting fingers whose relative positions may be varied. The discs are rotated through a clutch 179, 182 from a shaft 176 driven by the motor 177. When the timing mechanism is put into operation by the hand wheel 80 throwing in the clutch 179, 182, the fingers first cause the valve 199 to be opened to supply fluid to the spray nozzle 36 in the bowl, and then cause the valve 205 to be opened to supply fluid to the wash pipe 35 in the casing 10. Both valves are then locked in the open position. Another finger then causes the valve plate 19 to be raised so that the washing fluid escapes to the annular trough 15, and another finger releases the locking detent 103 on the brake mechanism so that the main clutch is disengaged and the brakes are applied. The only operations not subject to control from the hand wheel 80 are the charging of the bowl and the operation of the discharger 37.