| 摘要 |
<p>A hydraulic circuit for linearly driving a movable roller-holder slider of a pipe bending machine, comprising a hydraulic cylinder (5) whose piston rod is connected to a slider holding a movable roller, the cylinder being fed with pressurized fluid from a reservoir (16) by a pump (15), through a three-position four-way valve (18), a check valve (12, 13) and an interposed throttling valve (19), that is operated to generate an increased pressure in said low pressure chamber of the hydraulic cylinder (5) in order to slow down the slider holding the upper roller in its primary motion when a programmable interval is reached from said predetermined position for each working pass.</p> |
