Abstract: A saw for grooving concrete includes a base supported by a plurality of wheels such that a cutting guide of the base may press against the green concrete with a predetermined load. A cutter frame is pivotally mounted to the base and includes a cutting blade and drive means mounted thereto. The pivotal connection between the frame and the base is spaced from the cutting blade such that pivoting the frame with respect to the base will raise and lower the cutting blade between operative and inoperative positions. A handle is connected to the saw and extends rearwardly and upwardly therefrom such that an operator may stand behind the saw to push it during operation. The handle is pivotally mounted to the saw such that pushing the handle downwardly will cause the frame to pivot upwardly with respect to the base. The handle is telescopic and includes a pivot connection such that it may be folded to a storage or travel position.

Abstract: The abrasive cleaning device operates to direct streams of abrasive particles from a plurality of nozzles against a surface to be cleaned. The nozzles are recessed in a nozzle chamber and each receives a separate stream of abrasive particles from a divider unit. The divider unit receives a single stream of compressed air and abrasive particles and a supply source and separates the abrasive particles from the compressed air. The divider unit then divides the compressed air into a plurality of streams of equal pressure, and adds an equal amount of abrasive particles to each stream. A vacuum source creates a vacuum in an abrasive particle reclamation unit and in vacuum chambers connected to the abrasive particle reclamation unit. The vacuum chambers extend on each side of the nozzle chamber but are separate therefrom. Abrasive particles and debris from the surface to be cleaned pass through the vacuum chambers to the abrasive particle reclamation unit where the debris is separated from the abrasive particles.

Abstract: A machine for cutting transverse grooves in a concrete road surface includes a rotary cutter head supported on a carriage that can be shifted longitudinally along the machine frame structure. By using a combination of motions of the frame structure and cutter head carriage it is possible to form grooves spanning substantially the entire distance from one curb to the other curb during a single pass of the machine.

Abstract: A machine for cutting spaced grooves in a concrete road surface includes at least two laterally-spaced hydraulic cylinders which apply downward operating forces on a travelling cutter head. Each cylinder is individually pressurized through a pressure line that incorporates a pressure reducing valve and a pressure relief valve. The pressure setting for the relief valve is slightly higher than the setting of the reducing valve, such that the cylinder pressure is closely maintained between a high limit established by the relief valve and a low limit established by the reducing valve.

Abstract: An improved suspension system for a mobile machine adapted to work a material associated with a horizontal surface includes a frame mounting a prime mover. An arbor shaft extends transversely across the frame adjacent to a front end of the machine and is drivingly connected to the prime mover. The suspension system includes a live rear axle and a front axle assembly that is extendable and retractable whereby the machine is movable between raised and lowered positions. A rotating tool is mounted on the arbor shaft. Lowering the machine from its raised position engages the tool with the material. The improvement to the suspension system comprises a support device for providing extra support to the frame when the machine is in its lowered position, the support device being adapted to stabilize the machine when the tool exerts an upward reactionary force on the machine front end.

Abstract: A penetrable target element that is knocked over by a bullet, and is re-set to a standing position by a pull cord that is quickly attached and detached from the target element. After its mutilation by repeated gunfire, the target, with its removably attached pull cord is quickly and easily detached from a stationary part of a base, and an unused replacement target is quickly attached in its place. The replaceable target element contains both the pivot and pull cord connector devices within its single-part structure, and is stabilized and stands, otherwise unaided, on its bottom marginal edge.