Vibration dampened boring bar
First Claim
1. A boring bar having a longitudinal axis comprising a head section adapted to receiving a cutting insert,a hollow cylindrically shaped cemented carbide section,a cylindrically shaped intermediate section having an interior hollow portion, said intermediate section positioned intermediate said head section and said cemented carbide section,a first connection formed at the juncture of said intermediate section and said head section,a second connection formed at the juncture of said intermediate section and said cemented carbide section,a drawbar connected between said head portion and said cemented carbide section for holding said sections in axial alignment along said axis, said drawbar being under tension for holding said intermediate section and said first and said second connections under a compressive force,said drawbar and said cemented carbide section being provided with mating precision surfaces for centering said drawbar relative to the rearward section for preventing relative radial movement between the forward end of said drawbar and said cemented carbide section,at least one annular ring for dampening vibrations positioned in said hollow portion and positioned axially intermediate said head section and said carbide section,each of said first and said second connection comprising a key and a keyway and a pair of first and second surfaces,said first surfaces and said second surfaces, respectfully, extending on either side of said respective key and said keyway substantially within a plane perpendicular to said axis of rotation, andsaid first surfaces being adapted to meet the said second surfaces to align said head section, said intermediate section, and said cemented carbide section along said longitudinal axis.
3 Assignments
0 Petitions
Accused Products
Abstract
A boring bar has a longitudinal axis, with a steel head section having a cutting insert displaced from the longitudinal axis. In one embodiment, a cemented carbide section is joined directly thereto. In another embodiment, a intermediate section includes a devibrator body. The respective sections are joined by a centrally positioned drawbar threadedly inserted into the head section for maintaining a compressive force at the specifically configured connection between the axially aligned sections.
45 Citations
15 Claims
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1. A boring bar having a longitudinal axis comprising a head section adapted to receiving a cutting insert,
a hollow cylindrically shaped cemented carbide section, a cylindrically shaped intermediate section having an interior hollow portion, said intermediate section positioned intermediate said head section and said cemented carbide section, a first connection formed at the juncture of said intermediate section and said head section, a second connection formed at the juncture of said intermediate section and said cemented carbide section, a drawbar connected between said head portion and said cemented carbide section for holding said sections in axial alignment along said axis, said drawbar being under tension for holding said intermediate section and said first and said second connections under a compressive force, said drawbar and said cemented carbide section being provided with mating precision surfaces for centering said drawbar relative to the rearward section for preventing relative radial movement between the forward end of said drawbar and said cemented carbide section, at least one annular ring for dampening vibrations positioned in said hollow portion and positioned axially intermediate said head section and said carbide section, each of said first and said second connection comprising a key and a keyway and a pair of first and second surfaces, said first surfaces and said second surfaces, respectfully, extending on either side of said respective key and said keyway substantially within a plane perpendicular to said axis of rotation, and said first surfaces being adapted to meet the said second surfaces to align said head section, said intermediate section, and said cemented carbide section along said longitudinal axis.
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7. A boring bar having a longitudinal axis comprising a head portion adapted to receive a cutting insert and a hollow cylindrically shaped cemented carbide section,
a connection being formed at the juncture of said head section and said cemented carbide section, a drawbar connected between said head portion and said cemented carbide section for holding said sections in axial alignment along the longitudinal axis and holding said connection under compression for increasing the stiffness of the tool, said drawbar and said cemented carbide section being provided with mating precision surfaces for centering said drawbar relative to the rearward section for preventing relative radial movement between the forward end of said drawbar and said cemented carbide section, said connection comprising a transversely positioned key on one of said sections and a transversely positioned keyway being provided on said other of said sections, said connection including a pair of first and second surfaces, said first surfaces and said second surfaces, respectively, extending on either side of said respective key and said keyway substantially within a plane perpendicular to said axis of rotation, said first surfaces being adapted to mate with said second surfaces to align said head portion and said cemented carbide section along the longitudinal axis, and said first surfaces and said second surfaces, respectively comprising a major portion of the cross-sectional area of said boring bar.
Specification