HYDRAULIC CONTROL DEVICE FOR SEDIMENT FORCE-FEED PUMP FOR PIPE JACKING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a control device for a sediment force-feed pump for a pipe jacking device that can prevent the turbulence of a pipeline when changing an oil passage even if an oil passage changing means is installed on either the ground side or the pipe jacking device body side.;SOLUTION: In the case of changing the connection relation among a first hydraulic line 61, a second hydraulic line 62, a pressure oil discharge line 64 and a pressure oil supply line 63 on the basis of the detection of oil pressure rise by a first detector 41 and a second detector 42 in order to drive the sediment force-feed pump for the pipe jacking device, when the oil pressure rise of the hydraulic line 61 is detected by the first detector 41, a first pressure oil discharge logic valve 22 is opened by a pressure oil discharge selector valve 32 with a first throttle, to allow pressure oil in the first hydraulic line 61 to escape to the pressure oil discharge line 64 to gradually reduce the pressure to zero, and when the oil pressure rise of the second hydraulic line 62 is detected by the second detector 42, a second pressure oil discharge logic valve 24 is opened by a pressure oil discharge selector valve 34 with a second throttle, to allow the pressure oil in the second hydraulic line 62 to releaf to the pressure oil discharge line 64 and gradually reduce the pressure to zero.;COPYRIGHT: (C)2003,JPO