초록 ▼

A motorized finishing machine has a rotatable guard system enabling it to finish concrete surfaces next to walls, posts, conduits, or other obstacles. Deployed as a concrete trowel, the machine comprises an internal combustion motor that powers a gearbox to revolve a downwardly projecting rotor. Num

A motorized finishing machine has a rotatable guard system enabling it to finish concrete surfaces next to walls, posts, conduits, or other obstacles. Deployed as a concrete trowel, the machine comprises an internal combustion motor that powers a gearbox to revolve a downwardly projecting rotor. Numerous radially spaced-apart finishing blades controlled by the rotor frictionally contact the concrete surface being treated. A protective guard, which circumscribes the rotor, is rotatably suspended by a plurality of rollers. The guard, which is shaped somewhat like a truncated cone, comprises an inner ring coaxially secured above a larger diameter, outer ring. Radially spaced apart spokes extend between the upper and lower rings and brace the guard. The bearing-equipped rollers mounted by radially, spaced-apart arms have upper and lower flanges. The inner guard ring is captivated between the rollers, and it is vertically constrained between the roller flanges. When the guard contacts an obstacle it may freely rotate, enabling the power trowel to approach otherwise-unreachable surface regions without wobbling or rocking.

대표청구항 ▼

[ What is claimed is:] [1.] A surface finishing machine, said machine comprising:downwardly projecting rotor means for finishing said surface, the rotor means comprising means for frictionally contacting said surface;motor means for powering said rotor means;guard means for shrouding said rotor mean

[ What is claimed is:] [1.] A surface finishing machine, said machine comprising:downwardly projecting rotor means for finishing said surface, the rotor means comprising means for frictionally contacting said surface;motor means for powering said rotor means;guard means for shrouding said rotor means, said guard means comprising:an outer ring substantially coaxial with said rotor means and disposed vertically adjacent said surface to be finished, the outer ring comprising a diameter sufficient for it to circumscribe the outermost portions of said means for frictionally contacting said surface;an inner ring that is coaxial with and elevated above said outer ring, the inner ring comprising a diameter less than the diameter of said outer ring; and,suspension means spaced apart from said motor means for suspending said guard means for rotation in response to contact with obstacles, wherein said suspension means comprises a plurality of radial arms terminating in rollers.