摘要:
A rotary power tool operable in a first speed mode and a second speed mode comprising a motor shaft (6), a driveshaft (10) with an axis of rotation (42), a gear (24, 74) that is a component of a transmission (8) for transmitting torque from the motor shaft (6) to the driveshaft (10), a support member (48, 70), at least one bearing member (54, 76) which contacts the gear (24, 74), wherein the gear (24, 74), the support member (48, 70) and the at least one bearing member (54, 76) form an assembly that is in a first position along the axis of rotation (42) when the tool is operating in the first speed mode and is in a second position along the axis of rotation (42) when the tool is operating in the second speed mode, and wherein the at least one bearing member (54, 76) protrudes from the support member (48, 70) in the direction of the gear (24, 74) and rotates when the gear (24, 74) rotates.
摘要:
An underground drilling method where drilling fluid pulsing down hole tool is combined with a multiple in series pistons down hole tool to provide vigorous vibrations in the drill string and deliver vibrating energy to the drill bit to increase penetration rates and reduce friction between the drill string and the hole. One example method and apparatus shown can operate a simple percussive down hole mud hammer.
摘要:
A driver drill that can effectively prevent erroneous clutch operation in a drill mode is provided. A flat washer positioned between steel balls for locking an internal gear and a coil spring is rotatable by rotative operation of a mode-change ring. Also, protruding streaks are provided on a small-diameter unit of a second gear case around which a flat washer is externally mounted. The protruding streaks interfere with internal projections on an inner circumference of the flat washer at its predetermined rotating position to regulate a forward movement of the flat washer. When a drill mode is selected with the mode-change ring, the flat washer is locked by the protruding streaks.
摘要:
A shockproof spindle includes a spindle inserted into an elastomer having a compressible structure, and a sleeve having a hollow cylinder, sequentially. The sleeve caps the elastomer while the elastomer is pressed on the top of the base fixed at the bottom end the spindle to expose the chute of the spindle. The ball is then disposed in the chute of the spindle and the chute of the sleeve. After the sleeve is released to return the elastomer to its normal state, the sleeve, the elastomer and the spindle are held together by the ball which is retained in the chutes of the spindle and the sleeve. A C-shaped plate is then inserted between the elastomer and the base.
摘要:
A tool bit shank (11) for percussion drilling or chipping has at least three rotary entrainment grooves (13, 14, 15) extending in the axial direction and at least one locking groove (12) also extending axially. The rotary entrainment grooves (13, 14, 15) open at a free end (16) of the shank (11) so that rotary entrainment members of a tool bit chuck can be inserted axially into the rotary entrainment grooves. The locking groove is closed at its end adjacent the end face (16) to prevent ejection of the tool bit when it is engaged by a locking member of the chuck. To significantly reduce the wear of the tool bit shank and the tool bit chuck, the rotary entrainment grooves (13, 14, 15) are arranged in sequence in the circumferential direction in respect to radially outwardly facing circumferentially extending openings from the largest to the smallest opening. The locking groove (12) is located between the rotary entrainment groove (13) with the largest opening and the rotary entrainment groove (15) with the smallest opening. Similarly, the rotary entrainment members (43, 44, 45) in the tool bit chuck correspond to the size of their base cross-sections and are arranged in sequence from the largest to the smallest base cross-sections. The locking member is located between the rotary entrainment member with the largest base cross-section and the rotary entrainment member with the smallest base cross-section.
摘要:
In a hammer drill in which both rotationally and axially directed driving force components can be transmitted to a tool held in a tool holder, a coupling member is displaceable between three axially spaced positions. In the first position the coupling member transmits rotational driving force to the tool holder, in the second position the tool holder is freely rotatable and in the third position the coupling member locks the tool holder against rotation so that only axially directed driving force can be transmitted to the tool.