Envirotech Corporation

Baker International Inc.

Donald L King

Gerald S Glanville

Support of rake arms in a thickener is by sets of separate support cables and separate torque cables extending from outboard-of-the-center positions of rotating trusses extending radially of the sedimentation tank. The sets of support cables are attached in a vertical plane between spaced positions on a common point on the trusses to spaced radial positions along inner hinged rake arms so that the entire weight of the arms is taken up by the support cables. Torque cables extend from a single point on a truss generally midway of the truss but at a radially offset position from the center line of containing the support cable attachments on the truss or multiple trusses. The torquing or pulling action of the torque cables, also produces no thrust load along the rake arms. This eliminates the need of a heavy large center structure adjacent the rake arm hinges to absorb a rake arm thrust load against the hinges. The hinges are supported by relatively thin posts extending from the rotating trusses. Thus there is no large central structural members with scale build-up impeding the flow of settled material to the central sludge withdrawal outlet. Scale clean-up is reduced in magnitude and frequency due to a much reduced amount of structural steel and structure.

Cable supported rake arm thickener

An apparatus for driving and lifting the rake assembly in a sedimentation basin. An annular hub is mounted on the main gear member, such hub having slot means through which vertical edges of a vertically-extending rectangular torque-plate are slidably affixed. Torque is transmitted from the gear member, through the hub slot means, to the torque plate and to the rake assembly which is attached generally at the bottom of the torque plate. Side loads (horizontal unbalanced rake loads) are transmitted from the vertical edges of the torque plate through the hub slots to the main gear bearing in the drive. Means is also provided attached to the torque-plate to move the torque-plate upwardly through the slot means so as to raise and lower the rake assembly.

Rake drive and lifting device for sedimentation apparatus

A rotary rake structure for use in a settling tank comprises a torque transmitting member and a pair of rake arms. The torque transmitting member is mounted in the tank for rotation about a vertical axis. Each rake arm comprises one or more upper chords and one or more lower chords, the two rake arms being symmetrically disposed on opposite sides of the vertical axis of rotation along a transverse axis generally perpendicular to the axis of rotation. The upper and lower chords of each rake arm are fixedly positioned with respect to each other by truss members. The upper chords of both rake arms are attached to the torque transmitting member so as to permit pivotal motion of each rake arm in a plane containing the transverse axis and the vertical axis of rotation. Scraping devices depend from the lower chords for raking sediment at the bottom of the tank when the rake arms are rotated by the torque transmitting member. The end of each lower chord adjacent the axis of rotation terminates in a flange. The flanged end of each lower chord of one rake arm is spaced apart from the flanged end of a corresponding lower chord of the other rake arm by shim means in order to maintain each rake arm at a desired orientation with respect to the bottom of the tank.

Growing community of inventors

Bountiful, UT, United States of America

Donald L King