1·The dredge has several hemispheric scoops in place of the toothed bar.
这种捞网用几个半球状的铲子代替了锯齿横杆。
2·Dual-piston driven. toothed bar and gear driven, structure is compact, position of assembly is symmetrical. Motion is swift. turning of output axis can be changed through simple reversal of piston.
双活塞推动，齿条齿轮传动，结构紧凑，装配位置对称，动作迅速，通过简单的活塞颠倒可以改变输出轴转向。