Abstract: An electrically powered, self-propelled cart for safely delivering heavy loads, such as concrete, within job sites with unlevel, irregular, or sloped terrain. A cargo bucket is tiltable over front drive wheels for transporting and dumping cargo. Electric drive motors associated with a transaxle propel wheels at a selectable speed in response to an electric control module. A steering column rotates in response to manually operated handle bars and activates a sensor to generate signals delivered to the control module for throttle adjustments. The sensor may be a linear potentiometer, a rotary differential transformer or a rotary encoder or shaft encoder measuring angular displacement. Extreme steering displacements will electrically reduce cart speed notwithstanding the previous speed setting chosen by the operator through the steering column.

Abstract: A concrete finishing and forming machine adapted for rail trackbed deck construction accommodates various plinths and channels needed for light rail construction. The adjustably configurable machine comprises a rigid frame disposed above a deck by vertically upright, adjustable jack stands supported at their bottoms by wheeled, powered bogies adapted to traverse upon suitable rails on opposite sides of the deck. The jack-stands may be connected to supporting swing arms that extend from pivot sleeves enabling the jack stands to angularly swing out from the frame. A slidable carriage that is longitudinally displaceable within the frame supports at least one downwardly extending, vertically adjustable paving head having a tool that, when immersed within wet concrete and then horizontally displaced, strikes off elongated, smoothed channels resembling pathways upon the concrete.

Abstract: An adaptor assembly for concrete finishing trowels that enables efficient polishing of concrete surfaces, and trowels equipped with said adaptors. A large, rigid, circular adaptor disk supports a plurality of spaced-apart polishing rotors that project into contact with the concrete surface being treated. Each polishing head is rotatably secured to the adaptor disk with a spindle assembly including suitable alignment bearings. The spindle assembly secures a rigid header beneath the adaptor disk that sandwiches a resilient, annular coupler between itself and a rigid driver plate beneath the coupler. Bosses on the coupler insure spacing and enable proper flexure. The driver plate removably mounts a resilient finishing ring, that supports a plurality of radially spaced apart, downwardly projecting, diamond-equipped pucks that frictionally bear against the concrete surface for abrading and polishing.

Abstract: A high performance, riding trowel for finishing concrete comprises damage-preventing edge guard systems that accommodate destructive forces occasioned by collisions or impacts. Downwardly projecting, motor-driven rotor assemblies gimbaled to the frame contact the concrete with multiple blades for finishing. The rotors are tilted with linkages ideally controlled by a powered system that enhances operator control. A two-piece guard system is concentrically disposed over and rotatably associated with each rotor. The guard system comprises a captivating guard frame borne by the rotor and tilted during steering, which captivates and supports a rotatable ring guard portion that may non-destructively impact obstacles. The guard system frame suspends a plurality of rollers comprising upper and lower flanges. The rotatable guard ring is captivated upon the rollers, being vertically constrained between the flanges.

Abstract: A high performance, twin rotor riding trowel for finishing concrete and a joystick operated electro-hydraulic control circuit enabling complete joystick control to the operator. The rigid trowel frame mounts two spaced-apart, downwardly projecting, and bladed rotors that frictionally contact the concrete surface. The rotors are tilted with double acting, hydraulic cylinders to effectuate steering and control. Double acting hydraulic cylinders also control blade pitch. A joystick system enables the operator to hand control the trowel with minimal physical exertion. The proportional joystick system directly controls electrical circuitry that outputs proportional control signals to electrically controlled, proportional, pressure-reducing valves in line with the tilting cylinders. The hydraulic circuitry comprises a motor driven pump delivering pressure to a flow divider circuit. A bypass-valve in line before the flow divider enables an operator to customize the trowel steering characteristics.

Abstract: A two-person floating screed with laser-operated, automatic grade control apparatus for finishing plastic concrete is transformable for different operations. A rigid, transversely oriented float mounts a strikeoff for initially contacting and leveling rough, freshly poured concrete. In one form of the invention the screed merely floats upon the concrete surface. In an alternative embodiment, lightweight ski assemblies support the screed over the subgrade. The skis secure upwardly projecting screw jacks that removably couple to the screed and control elevation of the transverse float in response to laser signals. Each worker has a separate handle mechanism pivotally associated with the float. Separate, light-weight power sources are carried by each worker in a suitable backpack to power the screw jacks. Laser sensors mounted on vibration dampened stanchions emanating from the float respond to external laser beacons and display grade information so that the workers can make manual adjustments.

Abstract: A vibration system that fits on top of a conventional truss with minimal alteration. The system comprises a propulsion assembly powering a vibration assembly. The propulsion assembly comprises two parallel rails forming a lateral path between truss ends and supporting a mobile carriage. Each rail comprises abutting segments coextensively surmounting the truss. Each segment attaches at respective truss cross-beams to define a continuous runway for carriage movement. Each segment also defines a channel for a chain rack anchored at opposite truss ends. The carriage comprises an undercarriage supporting an offset platform. The undercarriage comprises a rail-spanning frame with supporting runway tracking wheels. A motor propels the carriage by turning an axle with terminal pinions entrained about the rack. The offset counterbalances the vibration assembly to reduce torsion. A coupling hitch protrudes from the platform opposite the offset to support the vibration assembly.