TH39702B - Twist drill - Google Patents

Abstract

DC60 Groove angle, Theta, in the section perpendicular to the drill axis of the groove, which is threaded (4), is established. The area of the groove (4) participating in the drilling chip operation is formed along a circle. First (S1) along the cutting edge (3) of the concave curve. and the second circle (S2) is inside this circle. Both of the first circle (S1) and the second circle (S2) are bounded on the third circle (S3), showing the net thickness, radius R of the first circle (S1) and radius R1 of the second circle (S2. ) in the range of 0.40D to 0.70D and in the range of 0.15D to 0.30D respectively, and the front in the direction of rotation around the drill (4a) of the spiral groove (4) is assembled on the second circle (S2 ) closer to the drill center than the fourth circle with a diameter of 0.65D, the angle radiating into the groove (formula) in the section perpendicular to the drill axis of the groove on which the spiral (4) is determined, the area of the groove (4). involved in the chip drilling operations are assembled along the first circle (S1) along the cutting edge (3) of the concave curve. and the second circle (S2) is inside this circle. Both of the first circle (S1) and the second circle (S2) are bounded on the third circle (S3), showing the net thickness, radius R of the first circle (S1) and radius R1 of the second circle ( S2) are in the range of 0.40D to 0.70D and in the range of 0.15D to 0.30D, respectively, and the front in the direction of rotation around the drill (4a) of the spiral groove (4) is assembled on the second circle ( S2) closer to the drill center than the fourth circle whose diameter is 0.65D.

Claims (3)

Disclaimers (all) that will not appear on the advertisement page: 1.Twist drill (1) with cutting edge (3) that creates a concave curve in the drill core end view, threaded groove (4) and thinning groove (5) that reduce edge width. Chisel (8), which is characterized by a spiral groove (4), has a fixed outlet angle of 80 ํ to 110 ํ in the cross-section view perpendicular to the drill rod, the radius angle of the drill. The groove is formed by a straight line reaching the outer end of the edge in the drill center cut, and a straight line leading from the drill center to the outer diameter through the section. In front of the drill rotation direction of the threaded groove in the cross-section view perpendicular to the drill rod and in which the area of such helical groove (4) that is involved in drilling chip control is created. Along the first circle (S1) and the second circle (S2) attached in the first circle (S1) in cross-section view. Perpendicular to the drill axis, both of the first circle (S1) and the second circle (S2) are tangent. Circle to the third circle (S3) showing the network thickness, the radius R of the first circle (S1) ranges from 0.40D to 0.70D and the radius R1 of the second circle (S2) is in range. 0.15D to 0.30D respectively assuming D represents the drill diameter. And the front part, the direction of rotation of the drill (4a) of such helical groove (4) is built on such second circle (S2) to be closer to the center. Drill over the fourth circle (S4) that is concentrically with the drill center. And has a diameter of 0.65D 2. The twist drill (1) according to claim 1, with the free edge (6) and the outer cutting edge (7) formed by the leading edge of the free edge (6), where the corner The alpha of the edge in the said pulley (7) cutting edge was set to positive. 3. Twist drill (1) according to claim 2, perform cutting edge strengthening by Raise the edge in the periphery (7) thereof.