| 摘要 |
A vibratory concrete screed composed of a plurality of interconnected sections. Each section includes a series of frame members which are located at an acute angle with respect to the longitudinal axis of the section. Each frame member is generally triangular in configuration and is composed of a base and a pair of sides which are connected together at an apex. The ends of the bases of the frame members are connected to a pair of parallel screed plates, while a ridge tube is connected to the apices of the frame members. The ridges tubes of adjacent sections are connected together by an adjustable connecting mechanism, and axial adjustment of the ridge tubes will tend to tilt the screed plates of one section relative to the adjacent section to provide the desired crown for the screed. The central portion of the base of each frame member is provided with a tubular hub and in one embodiment, the aligned hubs receive an eccentric shaft that is operably connected to an engine to provide vibratory motion for the screed. In another form of the invention, an air supply tube is mounted within the aligned hubs, and conduits serve to supply air under pressure from the supply tube to individual pneumatic vibrators mounted along the length of the screed. |
