Rotatable drilling tool as well as basic body therefor

Basic body for a rotatable drilling tool for chip removing machining, comprising:

• a body portion that extends axially along a longitudinal axis between a front coupling end and a rear fixing end;
• and
• at least one chip flute in the body portion,
• wherein each chip flute extends from the front coupling end toward the rear fixing end and is formed to receive a chip and to transport the chip to the rear fixing end,
• wherein in the front coupling end, the body portion has a female part that extends from the front coupling end axially inward in the body portion, which female part is formed for receipt of a male part of an insert top when the insert top is connected to the body portion,
• wherein the basic body comprises a wall portion between the female part and each at least one chip flute,
• wherein each chip flute, in each cross-section along the longitudinal axis of the body portion, has a depth, and the depth in each cross-section is equal to a difference between a radius of the cutting circle and a radius of a greatest possible core circle that has the longitudinal axis as the center and that is tangent to a limiting curve of the chip flute in the cross-section,
• wherein the body portion is longitudinally divided into a coupling segment that extends axially rearward from the front coupling end of the body portion and into a transportation segment that is situated axially behind the coupling segment, and the transportation segment extends rearward toward the rear fixing end of the body portion and that is longer than the coupling segment,
• wherein each chip flute extends through the coupling segment and the transportation segment,
• wherein the entire female part is situated in the coupling segment,
• wherein each chip flute has a smaller depth in the coupling segment than in the transportation segment, and
• wherein, for each chip flute, each cross-section along the axial length of the coupling segment has the same depth.

Rotatable drilling tool for chip removing machining comprising:

• a basic body;
• and
• an insert top that is detachably connectable to the basic body,
• wherein the insert top extends axially along a longitudinal axis between a front insert end having chip removing capacity and a rear coupling end, the front insert end having a cutting diameter that in an associated cross-section defines a cutting circle having the longitudinal axis as the center,
• wherein the basic body extends axially along a longitudinal axis between a front coupling end and a rear fixing end, and includes at least one chip flute,
• wherein the at least one chip flute extends from the front coupling end toward the rear fixing end and is formed to receive a chip removed by the front insert end and to transport the chip to the rear fixing end when the insert top is connected to the basic body,
• wherein in the rear coupling end, the insert top has a male part that extends axially outward from the rear coupling end,
• wherein in the front coupling end, the basic body has a female part that extends from the front coupling end axially inward in the basic body, which female part is formed for the receipt of the male part of the insert top when the insert top is connected to the basic body,
• wherein the basic body comprises a wall portion between the female part and each at least one chip flute,
• wherein the at least one chip flute, in each cross-section along the longitudinal axis of the basic body, has a depth, the depth in each cross-section equal to a difference between a radius of the cutting circle and a radius of a greatest possible core circle that has the longitudinal axis as the center and that is tangent to a limiting curve of the chip flute in the cross-section,
• wherein the basic body is longitudinally divided into a coupling segment that extends axially rearward from the front coupling end of the basic body and into a transportation segment that is situated axially behind the coupling segment, and the transportation segment that extends rearward toward the rear fixing end of the basic body and that is longer than the coupling segment,
• wherein the at least one chip flute extends through the coupling segment and the transportation segment,
• wherein the entire female part is situated in the coupling segment,
• wherein the at least one chip flute has a smaller depth in the coupling segment than in the transportation segment, and
• wherein each cross-section of the at least one chip flute along the axial length of the coupling segment has the same depth.

Basic body for a rotatable drilling tool for chip removing machining, comprising:

• a body portion that extends axially along a longitudinal axis between a front coupling end and a rear fixing end;
• and
• at least one chip flute in the body portion,
• wherein the at least one chip flute extends from the front coupling end toward the rear fixing end and is formed to receive a chip and to transport the chip to the rear fixing end,
• wherein in the front coupling end, the body portion has a female part that extends from the front coupling end axially inward in the body portion, which female part is formed for the receipt of the male part of an insert top when the insert top is connected to the body portion,
• wherein the basic body comprises a wall portion between the female part and each at least one chip flute,
• wherein the at least one chip flute, in each cross-section along the longitudinal axis of the basic body, has a depth, and the depth in each cross-section equal to a difference between a radius of the cutting circle and a radius of a greatest possible core circle that has the longitudinal axis as the center and that is tangent to a limiting curve of the chip flute in the cross-section,
• wherein the body portion is longitudinally divided into a coupling segment that extends axially rearward from the front coupling end of the body portion and into a transportation segment that is situated axially behind the coupling segment, and the transportation segment extends rearward toward the rear fixing end of the body portion and is longer than the coupling segment,
• wherein the at least one chip flute extends through the coupling segment and the transportation segment,
• wherein the entire female part is situated in the coupling segment,
• wherein the at least one chip flute has a smaller depth in the coupling segment than in the transportation segment, and
• wherein each cross-section of the at least one chip flute along the axial length of the coupling segment has the same depth.