摘要:
A fastener driving tool arranged to drive fasteners into a workpiece includes at least one electric motor having a central stator and an external rotor arranged to rotate around the stator. The rotor may be in the form of a flywheel. The tool includes an energy transfer member such as a driver arranged to transfer kinetic energy from the rotor to a fastener held in the tool, thereby to drive the fastener from the tool into a workpiece. The electric motor may be a brushless motor. The tool may include two such motors, arranged such that both of their rotors propel the driver simultaneously.
摘要:
A fastener driving tool arranged to drive fasteners into a workpiece includes a support, a pair of sub-assemblies movably mounted on the support, each sub-assembly comprising a motor and an associated flywheel, and a nose part retractable relative to the support. The tool is arranged such that, in use, when the nose part is retracted, its movement relative to the support mechanically forces the sub-assemblies toward each other. The forcing of the sub-assemblies toward each other by the retraction of the nose part may move the sub-assemblies from an inoperative position to an operative position.
摘要:
A hole saw has an arbor and a cup shaped cutting member. The cup shaped cutting member has an annular skirt with a plurality of teeth at its free end. A drill bit is secured on the arbor. The drill bit includes a pilot point with a first cutting edge. A second edge is formed on the body portion of the drill bit to form a constant diameter hole in the workpiece.
摘要:
A fastener assembly includes an elongate fastener, and a support collar mounted on the elongate fastener. The support collar is shaped such that it has profiles on opposite sides of the elongate fastener that are asymmetric with respect to each other. The asymmetry may be an asymmetry in the number, shape, position, or size of recesses on two opposite sides of the elongate fastener. A plurality of fastener assemblies may be provided as a fastener strip, in which each support collar is joined to one or two adjacent support collars in a strip.
摘要:
A fastener driving tool arranged to drive fasteners into a workpiece includes a support, at least one wheel movably mounted on the support, a driver arranged to contact and he guided by the wheel when the wheel is in an operative position in use, a nose part retractable relative to the support, and a connection mechanism to operatively interconnect the nose part with the wheel. The tool is arranged such that, in use, the retraction of the nose part causes the connection mechanism to move the wheel from an inoperative position to the operative position. Subsequent forward movement of the driver guided by the wheel toward the nose part causes the operative interconnection between the nose part and the wheel to be broken. Forward movement of the nose part relative to the support, subsequent to the operative interconnection between the nose part and the wheel being broken, causes the operative interconnection between the nose part and the wheel to be re-formed.
摘要:
An elongated drill bit has a shank at one end and working end at the other. A flute portion is between the working end and the shank. The flute portion is continuous with the shank and working end and is generally unitarily formed with them. The working end has a pilot tip with a first cutting portion. A second cutting portion is at the terminus of the flute portion and is axially spaced from the pilot tip first cutting portion. The second cutting portion includes a pair of cutting edges on opposing sides of the pilot tip. Each of the second cutting edges is on an angle from about 22° to 27° to a line transverse to the longitudinal axis. The cutting edges are defined by the junction of a rake face, defined by the flute surface, and a primary clearance face. Also, a secondary clearance face may be present which is continuous with the primary face at a different angle. The angle is about 50° to 65° with respect to the longitudinal axis.
摘要:
An elongate drill bit (20) with a longitudinal axis (X-X) has a shank (28), a working end (24), and a fluted section (26) between the shank and the working end. The shank, the working end and the fluted section are all formed integrally in the drill bit. The working end has an outer cutting portion (34) and a central pilot tip (36) which extends axially ahead of the outer cutting portion. The pilot tip is formed with at least one pair of minor cutting edges (40, 42; 44, 46) arranged on opposite sides of the axis. The outer cutting portion is formed with a pair of major cutting edges (70, 72) arranged on opposite sides of the axis. The outer cutting portion has a major diameter (D) defined by the pair of major cutting edges. The pilot tip has a minor diameter (d) defined by the at least one pair of minor cutting edges. The fluted section has a pair of helical lands (32) each with a respective inner surface (92) extending axially rearward from one of the major cutting edges and from one of the minor cutting edges. The helical lands define a web (94). Each helical land defines a respective helical flute (30). The helical lands have a pitch (S) and the web has a web thickness (K) at the pilot tip such that the ratio of the pitch to the major diameter (S:D) falls within a range of about 380% to about 410%. Also, the ratio of the minor diameter to the web thickness at the pilot tip (d:K) falls within a range of about 220% to about 380%.
摘要:
An elongated drill bit has a shank at one end and working end at the other. A flute portion is between the working end and the shank. The flute portion is continuous with the shank and working end and is generally unitarily formed with them. The working end has a pilot tip with a first cutting portion. A second cutting portion is at the terminus of the flute portion and is axially spaced from the pilot tip first cutting portion. The second cutting portion includes a pair of cutting edges on opposing sides of the pilot tip. Each of the second cutting edges is on an angle from about 22° to 27° to a line transverse to the longitudinal axis. The cutting edges are defined by the junction of a rake face, defined by the flute surface, and a primary clearance face. Also, a secondary clearance face may be present which is continuous with the primary face at a different angle. The angle is about 50° to 65° with respect to the longitudinal axis.
摘要:
A cutting plate (4) has a working end (20) to engage a workpiece and an axis (8) of rotation. A pair of oppositely arranged first faces (34) are inclined axially rearward from the working end (20) in an axial plane intersecting said first faces (34). A pair of second faces (30) are alternately arranged between the first faces (34). The second faces (30) are inclined axially rearward from the working end (20) in an axial plane (37) intersecting the second faces (30), and a pair of axis parallel front faces (24). Each of the front faces (24) is bound on three sides by a respective first face (34) and the pair of second faces (30). Each second face (30) is inclined radially inward from a transitional edge with a respective rotationally leading first face (34) in a plane normal to the axis (8) intersecting the transitional edge with a respective rotationally leading first face (34). Each first face (34) is inclined radially inward from a transitional edge (36) with a respective rotationally leading second face (30) in a plane normal to the axis (8) intersecting the transitional edge (36) with a respective rotationally leading second face (30), as the cutting plate (4) rotates.
摘要:
A resilient stop assembly for an impact tool includes first and second resiliently deformable parts, and a substantially rigid part situated between the deformable parts. Each of the first and second resiliently deformable parts and the substantially rigid part comprises: first and second opposite impact surfaces, at least one peripheral surface joining the impact surfaces, and an aperture extending entirely through the part between exit openings in the impact surfaces. The first impact surface of the second resiliently deformable part is separated from the second impact surface of the first resiliently deformable part by contact of those first and second impact surfaces with the substantially rigid part.