| 摘要 |
PCT No. PCT/JP94/00740 Sec. 371 Date Dec. 1, 1995 Sec. 102(e) Date Dec. 1, 1995 PCT Filed May 6, 1994 PCT Pub. No. WO94/27028 PCT Pub. Date Nov. 24, 1994An earth discharge control system for a small-diameter pipe propelling machine controls the excavated earth discharging operation of the small-diameter pipe propelling machine. The small-pipe propelling machine propels a small-diameter pipe (2) joined at its leading end to a leading pipe (1) into the ground by a propelling unit (3) installed in a starting shaft (4). Earth excavated by a cutting head (8) supported on the leading end of the leading pipe (1) is conveyed toward the starting shaft (4) by a screw conveyor (6) disposed within the small-diameter pipe (1). A pneumatically operated control valve (10) is disposed in combination with a portion of the screw conveyor (6) within the leading pipe (1). A pressure detector (23) detects the pressure in the pressure chamber (10a) of the control valve (10) and the amount of excavated earth contained in a portion of a casing (6b) extending ahead of the control valve (10) is estimated on the basis of the pressure in the pressure chamber (10a) of the control valve (10). The rotation of the screw shaft (6a) of the screw conveyor (6) is controlled on the basis of information thus acquired so that an optimum amount of excavated earth is taken always into the screw conveyor (6).
|
