Abstract: An improved tiltable rotating concrete mixing drum has a relatively flat rear conical charging zone, a front conical zone having a central discharge opening for discharging materials when mixed and a generally cylindrical central zone disposed between front and rear conical zones in which the overall length-to-diameter ratio is reduced. The improved mixing drum has two sets of mixing blades, one in the central or mixing zone and one in the front or discharge zone which is scoop-shaped and configured to increase the efficiency of mixing along the horizontal axis of the drum by increasing the overall mixing efficiency.

Abstract: Certain improvements are provided to the mechanical aspects of a tilt mixer which include a novel boggy, adjustable roller arrangement on the drum track which produces an improved distribution of the stresses produced by the extremely heavy rotating drum which reduces the wear on both individual rollers and on the track. An unique dual staggered-tooth gear drive is provided having two spaced sets of teeth each addressed by a pair of motor shaft mounted drive gears on each of a pair of flanking motors in which the teeth of the two sets are staggered or offset by one-half of the gear pitch. This produces a tighter, quieter drive which has been found to reduce gear wear. In addition, a unique torque tube system which possess a great deal more strength than previous drum tilt axles is provided to support the pivotal action of the drum thereby enabling the tilt point of the drum to be moved forward toward the discharge end of the mixers.

Abstract: An improved integrally mounted and operated dust hood is disclosed for a tilt mixer which minimizes the environmental effect of dust formed in the mixer which escapes from the discharge end of the drum. The integrally mounted dust hood of the invention includes a shaped sheet metal hood member which is hinge mounted from the forward drum support and operates in conjunction with the tilting of the mixer.

Abstract: A concrete mixing apparatus including a paddle type mixer and a cement and water container mounted on a scale. The cement and water container is divided into separate cement and water compartments mounted above and upon the mixer to permit gravity flow of their contents through an open top portion of the mixer. Aggregate is supplied by a belt conveyor through a side opening. All ingredients are supplied by weight based on the indication of the scale. The scale includes load cells supporting the mixer. The arrangement provides flexibility in the manner of introduction of cement, water, and aggregate into the mixer.

Abstract: A plenum chamber for an air slide conveyer is provided with two air chambers one within the other. The inner chamber communicates with a medial strip of the membrane which separates the chambers from the rest of the duct through which the material passes when fluidized by air from the plenum chamber. The central air duct also serves to support the membrane which is drawn over it and then clamped between the two halves of the duct. The supply of air to either the outer or inner chamber may be separately shut off. The lower half may be removed as a unit for repair or replacement of the membrane. A novel seal is provided for preventing the edges of the membrane from becoming wet and acting as a wick to moisten and clog the central portions of the membrane.

Abstract: A volumetric batcher is combined with a batch mixer so that similiar batches of powdered fluidizable material such as fly ash can be mixed with constant quantities of water resulting in mixtures having the same moisture. This enables their disposal at a land fill site or the like. To insure that the material in the batcher is settled to the desired degree before the inlet valve is closed, a high level indicator is provided which jogs the inlet valve to retard the rate of flow and this valve is allowed to continue to jog until a short period of time has elapsed during which the high level probe is constantly under the influence of the fly ash, at which time it is completely closed. Additional means are provided for insuring complete discharge from the batcher, measuring and timing the flow of water and removing air from the mixer and batcher during charging operations.

Abstract: The pan type mixing machine has vertical concentric annular walls between which material to be mixed is confined while paddles hung from a central revolving spindle churn such material. The transmission is supported on a ledge extending inwardly from the inner wall of the mixing space. The transmission is driven by a motor arranged outside the outer wall on frame members extending under the mixer, the frame members protecting the drive between the motor and the transmission. A novel seal is provided between the rotating spindle and the inner wall of the mixing chamber along with multiple means for adjusting the mixing paddles and protecting the arms that support them. The cover extending over the mixer space provides means for introducing liquid and also serves to reinforce the walls of the mixer when the latter is being lifted or lowered by a sling.

Abstract: A skirt assembly and swinging gate are both pivotally mounted on a bin hopper. The gate carries a cam which engages a follower on the skirt assembly. When the gate is closed, a notch in the cam face lifts the follower arm and the skirting assembly to its most elevated position. The final lifting action occurs while the gate is over-travelling its effective closed position. When it is desired to open the gate, the cam action is reversed until the skirt reaches sealing position; further engagements of the skirt assembly on the belt is prevented by a stop on the skirt which engages the hopper and operates with the cam face to lock the skirt in the exact position desired. It is held in this position during subsequent gate opening and regardless of the degree to which the gate is opened.