| 摘要 |
A concrete-finishing machine has a drive horse, a slave horse, and a bridge-like truss selectively connectable to, or separable from, those horses at different levels so those horses can roll along surfaces at the same level or at distinctly-different levels. Vertically-directed jacks can dispose a screed or a float at different distances below the level of the bridge-like truss, and that screed and that float can be shifted along the length of that bridge-like truss to avoid obstructions within the area to be concreted. Those jacks can set different sections of the screed at different levels and thereafter simultaneously move all sections of that screed up or down. Interacting surfaces on the jacks and on the bridge-like truss enable those jacks to be readily secured to or separated from that bridge-like truss. The bridge-like truss can consist of a single short, intermediate length or long section, or can consist of various numbers of short, intermediate length and long sections which are so rigidly interconnected that workmen can use that bridge-like truss as a bridge to cross over areas to be concreted and also can sit on the midpoint of that bridge-like truss to work on the concrete without causing appreciable deflection, even where the bridge-like truss is forty feet long. Aligning and coupling members interconnect adjacent sections of the bridge-like truss, and also protect the ends of those sections during the storage and shipment of those sections by projecting outwardly beyond the ends of those sections.
|
