Patent ID: 7938198

Claim:
A rotary digging and compression enlarging driller, comprising: a vehicle body; a pole adapted to be substantially vertically connected with the vehicle body; an outer drilling rod rotatably mounted to the pole in a longitudinal direction of the pole and movable in the longitudinal direction with respect to the pole; an inner drilling rod disposed within the outer drilling rod and moveable in the longitudinal direction with respect to the outer drilling rod; a windlass disposed in the vehicle body and connected with the inner drilling rod through a cable for raising, lowering, and hanging the inner drilling rod; a connecting lever having an upper end connected with a lower end of the inner drilling rod; a rotary digging bucket connected with a lower end of the connecting lever for boring; a rotary enlarging device for enlarging a hole having an end connected with the outer drilling rod and another end connected to the connecting lever adjacent to the lower end of the connecting lever, the rotary enlarging device being capable of protruding and retracting by moving the inner drilling rod in the longitudinal direction with respect to the outer drilling rod; a driving device movable in the longitudinal direction with respect to the pole for driving the outer drilling rod to rotate, thereby driving the rotary enlarging device, the connecting lever, the rotary digging bucket, and the inner drilling rod to rotate; and a first hydraulic cylinder having an end connected with the outer drilling rod and another end connected with the inner drilling rod for driving the inner drilling rod to move in the longitudinal direction with respect to the outer drilling rod, thereby protruding and retracting the rotary enlarging device.