Abstract: A handling and transporting apparatus having a lifting and lowering frame supported by hydraulically actuated parallelograms at each end from transporting frames.

Abstract: A paving machine having a medially located dowel bar feeder positioned in front of a dowel bar inserter. The machine has a screw or paddle for spreading the concrete and a front strike-off to allocate a proper amount of unconsolidated concrete beneath the machine. Next in line, internal vibrators are mounted to the machine to perform a preliminary consolidation of the concrete, followed by a screed to meter out a correct volume of consolidated concrete for a finished concrete slab. To the rear of the screed, the dowel bar feeder drops dowel bars in a predetermined pattern on the top surface of the consolidated concrete. The dowel bar inserter is mounted to the paving machine behind the dowel bar feeder and is adapted to travel between a forward position and a rear position and includes a plurality of vibrating forks which descend to engage the dropped dowel bars and insert the dowels into the unhardened concrete.

Abstract: A closed, pressurized dust return system for introducing aggregate dust into a stream of liquid asphalt is provided. Aggregate dust is dispensed through a valve from a receiving chamber into a mixing housing. The aggregate dust enters the mixing housing at an intermediate location therein. The liquid asphalt is introduced into the mixing housing through a separate conduit at a location thereon above the point of entry of the aggregate dust. The liquid asphalt and the aggregate combine within the mixing housing to form a slurry composition. A heating jacket substantially surrounds the mixing housing and a system for preventing liquid asphalt from backing up into the receiving chamber is also provided. The dust return system is particularly useful in an asphalt plant using a baghouse.

Abstract: An asphalt production system utilizing a pair of rotatable drums for producing an asphaltic composition is provided. The asphaltic composition is produced by separately heating a volume of virgin aggregate material in a countercurrent drum dryer and heating a volume of recycle material in a parallel flow drum mixer. The hot virgin aggregate material is mixed with the heated recycle material at an intermediate location within the parallel flow drum mixer. A ducting system is provided for interconnecting the ends of the drums such that the hot exhaust gases from one drum are circulated into the other drum thus producing a common flow of exhaust gases between the drums.

Abstract: An apparatus and method for adjusting the air-fuel ratio of a burner in order to minimize the presence of undesirable emissions in exhaust gases of the burner combustion. A burner calibration is performed by selecting a number of calibration points corresponding to burner fuel positions. Air flow is varied for each calibration point as an exhaust gas analyzer determines the content of exhaust gases of the burner combustion. Air settings for optimal combustion are determined for each calibration point and are stored in a programmable logic controller and software. During plant operation, the programmable logic controller and software adjust the air supplied to the combustion of the burner according to the calibration data and the fuel position of the burner.

Abstract: An improved silo for storing materials which are composed of particles of varying sizes. Rectangular receiver openings are located in an upper floor at the upper end of the silo and rectangular discharge openings are located at the lower end of the silo. In order to reduce particle segregation caused by differences in the sizes of the particles, the receiver openings are positioned at right angles to the discharge openings.

Abstract: A system for removing and relaying asphaltic concrete pavement using a planer pulling a laydown machine and pushing equipment for (a) screening the cuttings produced by the planer, and (b) mixing the screened cutting, with a suitable binder, wherein the mix is conveyed back to the laydown machine.

Abstract: A center bar inserter having a frame for supporting a plurality of forks for pivotal movement about a horizontal axis is provided. Insertion of a center bar is preformed by simultaneously extending the forks into the concrete slab while the forks pivot about a horizontal axis. A pair of vibrating sleds are secured to the float pan reward of the center bar inserter for repairing the surface of the concrete slab disturbed by the insertion of the center bar.

Abstract: A concrete finishing machine includes a surfacing unit having one or more finishing rollers supported on the surfacing unit carriage by a finishing roller vibrating assembly which includes a frame supporting the finishing rollers at one end and on which is mounted a pair of vibrator units producing vibrational forces which are applied to the finishing rollers through the frame, the vibrator units being mounted on a common beam and spaced apart laterally of one another whereby horizontal forces are cancelled and only vertical amplitude vibrational forces are applied to the finishing rollers.

Abstract: A drum mixer is provided for producing an asphaltic composition. The drum mixer utilizes a first heat source located at an intermediate position within the drum mixer for producing a first current of hot gases directed towards the entry end of the drum mixer. The drum mixer also utilizes a second heat source located at the discharge end of the drum mixer for producing a second current of hot gases directed towards the entry end. Virgin aggregate is introduced into the drum mixer at the entry end of the drum mixer and is heated by the first current of hot gases. Recycle material is introduced into a mixing zone within the drum mixer between the first heat source and the discharge end. The heated virgin aggregate combines with the recycle material in the mixing zone and is further heated by the second heat source. Liquid asphalt is mixed with the virgin aggregate and recycle material in the mixing zone and the product is removed from the drum mixer at the discharge end.

Abstract: An improved ceramic tile conveyor is provided having a pair of guide plates extending substantially the length of the conveyor. The guide plates provide an impact barrier protecting the ceramic tile from damage caused by contact with the revolving flights of the slat conveyor.

Abstract: A improved silo is provided having a pair of pivoting receiver gates overlying a pair of receiver openings and a pair of pivoting discharge gates overlying a pair of discharge openings. A deformable seal is secured to the silo between the receiver openings and the receiver gates and between the discharge openings and the discharge gates. The gates are vertically adjusted by an eccentric assembly to compress the respective deformable seal for forming an air tight barrier between the respective openings and the gate.

Abstract: A plurality of variable pitch baffles for diffusing hot combustion gases flowing through an asphalt drum mixer is provided. Each baffle, which is internally mounted at an intermediate location within the drum mixer, includes a plurality of opening therethrough.

Abstract: An apparatus to be towed behind a roadway planing machine to mix aggregate planed from a roadway into cold mix asphalt for repaving the roadway. The aggregate is introduced, via an inclined shaker screen, into a surge bin and conveyed from the surge bin to a pugmill on the chassis of the apparatus by a belt conveyor underlying the surge bin. The conveyor is driven through an electrically adjustable first variable transmission and manual and automatic controls are provided to adjust the speed ratio of the first transmission to maintain the level of aggregate in the surge bin between selected high and low levels. A pump is driven by the first variable transmission through a second variable transmission to select and fix the ratio of aggregate to asphaltic composition in the pugmill for varying rates of conveyor operation corresponding to different speed ratios of the first transmission.

Abstract: A portable, self erect silo for hot mix asphalt having two, side-by-side bins. A single drag slat conveyor directs hot mix asphalt into either bin by use of a single slug feeder pivotally attached to the discharge end of the conveyor.

Abstract: A drum mixer having a internal combustion gas cylinder extending substantially the length of the drum mixer is provided. Hot combustion gases are generated by a flame within the cylinder. The combustion gases within the cylinder flow in a countercurrent direction the to the flow of material within the drum mixer. The combustion gases exit the cylinder generally at the receiving end of the drum mixer and are directed towards the discharge end thereof in a parallel relation to the flow of material. The horizontal position of the flame within the drum is adjustable and a valve for mixing the gases within the drum adjacent the discharge end thereof with the flame is also provided.

Abstract: This application discloses several components relating to a heating apparatus which preferably are used in conjunction with each other in an apparatus for heating solid granular or particulate material, such as aggregate used to make asphalt concrete. One component of the present invention includes a heater-condenser unit which indirectly heats the material by circulating heat transfer fluid within hollow plates contained in a housing holding the material. The material is heated, the heat transfer fluid is condensed and a condensate removal means associated with the hollow plates removes the condensate from the housing. The heat transfer fluid used in the heater-condenser preferably is supplied in the form of a vapor or gas evolved from liquid contained in material heated by another type of heater. In this other type of heater, the material to be dried enters a chamber containing hollow heat exchange plates through which a primary heat transfer fluid is circulating.

Abstract: A concrete finishing machine includes a surfacing unit having two finishing cylinders with two augers mounted in line with the two cylinders, and a pair of compacting rollers located on either side of the augers, suspended by a frame which is attached to the surfacing unit by a mounting assembly which allows adjustment in the vertical height of the compacting rollers relative to the surfacing unit for setting the compacting rollers relative to the surface being finished. The frame is adapted to be vibrated for vibrating the compactor rollers in use. In one embodiment, the compacting rollers each have rectangular fins projecting radially outward from the roller and extending the length thereof. In another embodiment, the compacting rollers each have a serrated outer surface.

Abstract: A concrete finishing machine includes two finishing cylinders with two augers mounted in line with the two cylinders, forward ends of the augers being suspended by a frame which is pivotally attached to the cylinder support frame and rearward ends of the augers being connected through flexible couplings to the output ends of the cylinder shafts, allowing adjustment in the angle of inclination of the auger support frame, pivoting the two augers relative to the plane of the cylinder shafts.

Abstract: A hydraulically controlled seismic energy source for impressing individual seismic energy pulses into the ground, wherein the hydraulic pressure forcing the ram downwardly is substantially reduced slightly before the ram contacts the ground, and a continual upward hydraulic force is applied to a downwardly facing surface of the ram, whereby the ram is quickly removed from the ground after a seismic impulse is generated to prevent secondary contact between the ram and the ground.