| 摘要 |
A control system (79) for selectively moving load engaging forks (52,54) along a carriage frame (36,46) in first and second modes of operation is provided. In the first mode of operation the first and second forks (52,54) are movable in unison and at the same rate of speed along the carriage frame (36,46) and in the second mode of operation the forks are individually selectively movable. The control system (79) includes a main control valve (84) and first (114), second (116), and third (118) selector valves for directing fluid flow delivered by the main control valve (84) to first and second fluid operated jacks (60,62) connected to the first and second forks (52,54), respectively, and the carriage frame (36). The third selector valve (118) directs fluid flow between head ends of the jacks in the first mode of operation so that the first and second forks (52,54) move in unison on the carriage frame (36,46). The control system is particularly suited for use on a a material handling vehicle having a lift mast assembly. |
