To provide an automatic penetration test machine capable of stably achieving load control by feedback while reducing an impact load when a penetration rod penetrates into the ground.
An automatic penetration test machine 1 includes: a lifting and lowering base 3; a chuck 5 provided on the lifting and lowering base 3 and holding a penetration rod 4; a lifting and lowering motor 8 for performing the lifting and lowering operation of the lifting and lowering base 3; a load cell 22 for detecting a load applied to the tip of the penetration rod 4; and control means 10 which, after the lifting and lowering base 3 at an elevation position has been lowered at a high speed by controlling the speed of the lifting and lowering motor 8 and immediately before the tip of the penetration rod 3 penetrates into the ground, issues a deceleration command to the lifting and lowering motor 8, and when the penetration rod 4 penetrates into the ground, switches the lifting and lowering motor 8 to load control and compensates the output torque of the lifting and lowering motor as necessary while feeding back the detection value by the load cell 22, thereby applying a target test load.
ISONO KAZUNORI
JP2004278114A | 2004-10-07 | |||
JPH11211648A | 1999-08-06 | |||
JPH0995931A | 1997-04-08 |