Reciprocated concrete surfacer member with shielded spring return

摘要

A scabbler apparatus having a conventional reciprocated rod is provided with a bit secured to a shank member. A compression spring is adapted to urge the shank and rod upwardly while motive means is provided to drive the rod, shank and bit toward the surface of concrete, rock and the like and against the bias of the spring. A protective retainer and an exclusionary means is provided. This exclusionary means may be a boot, a wiper ring and with or without a one-way valve means. The compression spring is retained at its lower end by a support shelf, usually an inwardly formed flange of the retainer. A washer or ring engages or is carried by the shank of the bit and engages the top end of the spring to urge the shank, the attached bit and the reciprocated rod upwardly.