Abstract: In an underground borer with down hammer having a vehicle body 1, a guide stilt 2 standing on the vehicle body, and a rotary machine 4 having its bottom coupled with a screw shaft 3 and a down hammer B, a supply unit 5 is interposed between the rotary machine 4 and the screw shaft 3, a fluid conduit 6 is formed centrally of the screw shaft 3, compressed air conduits 7 and 7' are formed to surround the fluid conduit 6, and a fluid jetting pipe 8 is arranged centrally of the down hammer B to extend until the inside of a bit body 9 so that water may be discharged, along with high-pressure compressed air, from a central portion of the bottom surface of the bit body during boring to cool the bit body, promote anti-wear properties, suppress powdery dirts, reduce noises and increase the boring speed.

Abstract: There is provided a cement soil apparatus of underground borer capable of improving the efficiency of operation such as pile driving in civil engineering foundation work. A screw shaft 3 and a rotary machine 4 for rotating it are disposed on a guide stilt 2 of a vehicle body 1, a down hammer 6 formed with a screw blade 5 is connected to a lower end of the screw shaft, supply conduits 10, 10' and 11, 11' for cement milk or the like are formed in the screw shaft and the down hammer, respectively, such that the supply conduits in the screw shaft are in communication with those in the down hammer, and valves 12, 12' openable by pressure are disposed in lower end portions of the supply conduits, whereby cement or the like can be supplied from the outside to the inside of a bored hole. When boring operation ends and the down hammer is pulled up, cement milk is grouted.

Abstract: A first rotation driving mechanism including a hydraulic motor (26), a driving gear (27), and a driven gear (29) is provided between a coupling arm unit (12) attachable to the operational arm of a construction machine such as a hydraulic shovel, etc., and a hanger unit (14) to relatively rotate them in the horizontal plane, and at the same time, a second rotation driving mechanism including a hydraulic cylinder (32) and a rocking arm (34) is provided between the hanger unit (14) and a main body (20) to rotate them in the vertical plane. The positional changes of the hanger unit (14) and the main body (20) are automatically performed by a remote control rapidly and easily, and further, with safety to improve the mobility and operativity of the piling, and the pile installation and removal.

Abstract: A vibration generator comprises a first rotational shaft 21 and second rotational shaft 22, with fixed driving gears 31 and 33, movable driving gears 32 and 34, fixed eccentric weights 51A and 52A, and movable eccentric weights 51B and 52B, and on the outer periphery of the phase adjustment shaft 23 which is arranged in parallel therewith, spiral grooves 61 and 62 are provided at two locations in the rotative directions opposite to each other, and at the same time, on the inner periphery of a pair of phase adjustment gears 35 and 36, pins 63 and 64 are planted to be slidably fitted into the above-mentioned spiral grooves 61 and 62. Then, the phase adjustment shaft 23 is forced by a cylinder 50 in the axial direction.The vibromotive force can be varied arbitrarily and infinitely, even during operation; yet the structure is simple and rational, and is fabricated easily.

Abstract: A pile driver includes an attachment frame fixed to a work arm of appropriate construction equipment that serves as a base machine, a vibration cylinder actuated and controlled by an electro-hydraulic hydraulic servo-valve and mounted on the attachment frame through a rubber buffer, and a counter weight and a chucking means for gripping a pile to be driven K provided on the axial ends, that is, on the cylinder base and on the forward end of the piston, the pile being held in such a manner that the drive direction coincides with the axis of the vibration cylinder.