Abstract: A sweeping machine has a housing, wheels for moving the housing, a sweeping brush mounted on the housing, a hopper positioned adjacent the brush to receive dust and debris therefrom, a dust collection chamber on the housing, and a vacuum fan mounted on the housing and creating an air flow path from the brush through the hopper and to the dust collection chamber. There is a filter element in the air flow path, with the filter element including a plurality of generally parallel pleats having folds extending in a direction transverse to the air flow path. There is a pleat moving element extending generally transverse to the pleats and engaged with the pleats. An electric actuator is mounted on top of the pleats and a bar is associated with the actuator and movable upon actuation thereof. There is a spring connected between the pleat moving element and the filter frame.

Abstract: This invention is a paving or resurfacing machine and method that places and trowels a layer of a trowelable coating material or overlay, such as a filled resinous material, on a surface to be coated, such as a concrete floor. The machine meters, distributes, strikes off and compacts a resurfacer material on a prepared surface resulting in a closed, smooth, dense, flat surface.

Abstract: A method of operating a vehicle having an electric hybrid power system comprising a battery powered electric motor connected to drive the wheels of the vehicle and a combustion engine which may be releasably coupled mechanically to the electric motor. When so coupled the combustion engine may drive the vehicle and the electric motor may act as a generator to maintain a desired charge level in the batteries. In operation the power train is automatically controlled by a process controller to produce maximum fuel economy for the engine and to maintain the batteries at an acceptable charge level. Means are provided to apply the combined power of the electric motor and the combustion engine to the drive wheels for short duration peaking power. Means are also provided whereby the combustion engine may drive the electric motor to function as a generator and charge the batteries when the vehicle is stationary.

Abstract: This invention is concerned with a machine and method for automatically removing a curing film or membrane from a concrete floor surface and etching that surface in preparation for applying a surface coating and doing this in less time than has heretofore been required for such floor preparation.

Abstract: This invention is concerned with a machine for automatically removing a curing film or membrane from a concrete floor surface and etching that surface in preparation for applying a surface coating and doing this in less time than has heretofore been required for such floor preparation.

Abstract: A scarifying tool is disclosed suitable for use in conjunction with disc floor maintenance machines. The scarifying tool includes a support plate with a plurality of resilient or flexible members attached thereto. The flexible member may be lightweight spring-steel strap material one end of which is secured to a disc plate. A cutter is then mounted on the strap at a point spaced from the disc support.