Patent ID: 11969807
Assignee: TAEGUTEC LTD.
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 16:
17. A rectangular cutting insert having a height direction centerline (M1) around which the insert has 180° rotational symmetry, the insert comprising:
an upper surface including first, second, third, and fourth upper corner portions arranged in order in a counterclockwise direction taken about said height direction center line (M1) in a top view of the insert, with respect to the first upper corner portion;
a lower surface formed below the upper surface in a height direction of the cutting insert, and including a first lower corner portion below the first upper corner portion in the height direction, a second lower corner portion below the second upper corner portion in the height direction, a third lower corner portion below the third upper corner portion in the height direction, and a fourth lower corner portion below the fourth upper corner portion in the height direction;
a first main cutting edge formed at the first upper corner portion;
a second main cutting edge formed at the third upper corner portion;
a first ramping cutting edge formed at the second upper corner portion;
a second ramping cutting edge formed at the fourth upper corner portion; and
an opening passing between the upper and lower surfaces, the opening having said height direction center line;
wherein the second lower corner portion and the fourth lower corner portion are rotationally symmetrical with respect to said height direction center line,
wherein the first lower corner portion and the third lower corner portion are rotationally symmetrical with respect to said height direction center line and are located above the second and fourth lower corner portions in the height direction,
wherein the lower surface comprises:
a lower ridge portion protruding downward in the height direction and extending between the second and fourth lower corner portions in a diagonal direction passing through the second and fourth lower corner portions;
a first lower support surface formed on a side of the lower ridge portion; and
a second lower support surface formed on an opposite side of the lower ridge portion,

wherein the first and second lower support surfaces are inclined upward in the height direction from the lower ridge portion and define an obtuse angle along the lower ridge portion, and
wherein the first lower support surface extends from the lower ridge portion to a peripheral edge of the lower surface in the first lower corner portion, and the second lower support surface extends from the lower ridge portion to a peripheral edge of the lower surface in the third lower corner portion.