Patent GB-362933-A (GB)
Title: Improvements in filtering apparatus
IPC: B01D33/073
Filed: 1930-09-05
Abstract: 362,933. Filters ; toothed gearing. BARTLETT HAYWARD CO., Scott Street, Baltimore, U.S.A.-(Assignees of Center, A. L. ; c/o Bartlett Hayward Co., Scott Street, Baltimore, U.S.A.) Sept. 5, 1930, No. 26575. Convention date, Oct. 2, 1929. [Class 46.] In apparatus comprising a rotary filter element partially immersed in the liquid to be filtered, means are provided for giving to the element an oscillatory movement relatively to the liquid container, such oscillatory movement being approximately perpendicular to the vertical paths of settlement of the solid particles in the liquid. Tubular filtering elements 19 are mounted in end members 14, which are rotated so that each element is submerged in the material under treatment in a trough 12 and then raised for the discharge of separated solid matter from the element. The rotational movement is oscillatory, each forward step being succeeded by a shorter backward step, and the elements themselves keep the material under treatment in agitation. Each tubular element comprises filtering material 25, Fig. 7, wound or stretched over a tube 20 which has external ribs or corrugations 21 and is slotted so that the spaces between the ribs communicate with the inner space 24. The tubes are attached to the end members 14 by means of screws 27, and one end member is formed with passages 30, Fig. 2, which connect the elements to a distributing valve 36, by means of which each element is successively subjected to suction and supplied with fluid under pressure to discharge the solid matter from the element. To facilitate communication between the elements and the passages 30, the elements are made to taper slightly towards the opposite end. Solid matter falls from the elements into a hopper 50, Fig. 3, and is passed by a conveyer 54 to a discharge shoot at one end. The material is supplied to the trough through a pipe 86. Longitudinal bars 88 and vertical bars 89 prevent rhythmic movement of the material. The removal of the cakes from the elements is aided by a flexible wiper 92 attached to a rigid support 90 which can be adjusted on brackets 91, so that the wiper is not in actual contact with the filtering material. An auxiliary wiper 97 hinged to the support 90 may also be provided. The end members 14, which are carried by annular runners 15 engaging rollers 16 on frames 17 supported on flanges on the edges of the trough 12, are rotated by toothed wheels 57 meshing with gear wheels on a longitudinal shaft 59, Fig. 3. Suitable gearing for giving the shaft 59 the desired motion is shown in Fig. 12. A driving shaft 63 carries an eccentric 66 with a pinion 69 fixed thereto. The pinion gears with a wheel 71 on a shaft 72 which also carries a wheel 73 gearing with a wheel 74 on the shaft 59. The shaft 72 is mounted in a casting 75 which is free to oscillate on the shaft 59. An arm 78 connected to the shaft 72 and to a disc 81 connected to the stub shaft of the pinion 69 keeps the pinion in gear with the wheel 71. As the eccentric 66 rotates with the shaft 63, the shaft 72 is rotated by the pinion 69 and is at the same time oscillated about the shaft 59, and the shaft 59 is rotated discontinously each forward step being succeeded by a shorter backward step.