Patent GB-424834-A (GB)
Title: Improvements in and connected with hydraulic washing, cleaning and separating apparatus, particularly adapted for cleaning coal
IPC: B03B5/20
Filed: 1933-07-24
Abstract: 424,834. Washing granular materials. TUGWOOD, R. J., 77, Chancery Lane, London.-(Jeffrey Manufacturing Co. ; 1st Avenue, Columbus, Ohio, U.S.A.) July 24, 1933, No. 20834. [Class 82 (ii)] [See also Group XXVI] The pulsations of liquid in a jig are produced by the action on the liquid of gas under pressure, preferably compressed air supplied at a substantially constant pressure, the gas chamber being first opened to admit the gas, then sealed for a period of more than 20‹ of a cycle of 360‹, and then opened to exhaust the gas. The chamber is preferably again sealed for a period before the gas is admitted at the commence - ment of the next cycle. The mechanism controlling the action of the gas is preferably adjustable so that the periods of admission, sealing, and exhaust, and the rate at which the gas is admitted and released can be varied, and may be adjusted so that the liquid rises through the screen at a velocity which increases slowly at first and then more rapidly, the velocity being maintained approximately at its maximum value for a short period, and then rapidly reduced. The period of upward flow may be followed by a suction period, during which the liquid preferably moves downwardly with a rapidly increasing velocity at first and then with a slowly decreasing velocity. The jig shown comprises an air chamber 24 and a screen chamber 25, separated by a plate 23 the lower portion of which may be hinged so that its inclination can be adjusted. An inclined screen 28 with reinforcing guiding ribs 28<1> on its under side is mounted in the chamber 25, preferably in such a manner that its inclination is adjustable. The screen terminates at a refuse outlet 29 leading to a discharge shoot comprising a stationary guide plate 47 and a pivoted guide plate 46, which directs the refuse to a rotary discharge valve 48. The refuse is discharged by the valve into a compartment 49 from which it is removed by a bucket elevator 50, driven by a motor 44 which also reciprocates a pawl controlling the rotary valve 48. Fine particles of refuse passing through the screen are carried by a screw conveyer 53 through a small door 55 into the elevator compartment 49. The screw conveyer is driven from the foot shaft of the elevator and is mounted so that it can be easily removed. A water-inlet 31 controlled by a valve 32 is provided in the air chamber 24. An air-compressor 33 communicates with a pressure tank 34 from which extend conduits 36, one for each of the subcompartments into which the tank is divided by a plate 38, each conduit having a control valve 39 and communicating with the upper part of a chamber 24 under the control of a reciprocating valve-device 40. The valvedevice is of the form described in Specification 424,878, and may be reciprocated by the eccentric mechanism described in that Specification or by a cam device. According to the Provisional Specification the washed material may pass over an auxiliary inclined screen plate on to the screen of a second jig. Specification 344,082 also is referred to.