Patent attributes
A roller tube concrete finishing machine includes retractable vibration gangs that can be selectively immersed within wet concrete and then retracted with parallelogram linkage. Spaced-apart, drive parallel rollers are journaled between frame ends for supporting and propelling the machine upon and between parallel form rails. A front roller provide a strike-off function. The vibration gangs are deployed by a retractable, parallelogram linkage that moves them forwardly and downwardly for operation, or which retracts the vibrators inwardly and upwardly relative to the frame. When the vibrators are retracted, the are withdrawn upwardly from the concrete and retracted rearwardly towards the machine front to reduce machine dimensions. Substantial retraction of the vibrators prevents subsequent interference with the rebar below. Vibrator retraction reduces overall machine dimensions for clearance and shipping purposes, with gang vibration arrays nested upwardly and inwardly proximate the front of the machine.
