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EP-4739451-A1 - DRILLING TOOL WITH A DRILLING HEAD WHICH HAS A CENTRAL PYRAMID

EP4739451A1EP 4739451 A1EP4739451 A1EP 4739451A1EP-4739451-A1

Abstract

The invention relates to a drilling tool, in particular a rock drilling tool, comprising a drilling head (130), which has a central pyramid (250) with at least four cutting edges (251, 252, 253, 254), and at least two diametrically opposed main cutting elements (220, 240), each of which has a main cutting edge (221, 241) and at least two diametrically opposed auxiliary cutting elements (210, 230) with a respective auxiliary cutting edge (211, 231), wherein a respective auxiliary cutting element (210, 230) is arranged between each pair of main cutting elements (220, 240) adjoining each other in the circumferential direction (198) of the drilling head (130). In such a drilling tool, each cutting edge (251, 252, 253, 254) of the at least four cutting edges (251, 252, 253, 254) of the central pyramid (250) is arranged between each main cutting element (220, 240) of the at least two diametrically opposed main cutting elements (220, 240) and each auxiliary cutting element (210, 230) of the at least two diametrically opposed auxiliary cutting elements (210, 230), said auxiliary cutting elements adjoining each other in the circumferential direction (198) of the drilling head (130).

Inventors

  • Schurig, Andreas
  • WIDMANN, RAINER

Assignees

  • Robert Bosch GmbH

Dates

Publication Date
20260513
Application Date
20240614

Claims (10)

  1. 1. Drilling tool (100), in particular a rock drilling tool, with a drill head (130) which has a central pyramid (250) with at least four cutting edges (251, 252, 253, 254), and at least two diametrically opposed main cutting elements (220, 240), each with a main cutting edge (221, 241), and at least two diametrically opposed secondary cutting elements (210, 230), each with a secondary cutting edge (211, 231), wherein a secondary cutting element (210, 230) is arranged between two main cutting elements (220, 240) adjacent in the circumferential direction (198) of the drill head (130), characterized in that between each main cutting element (220, 240) of the at least two diametrically opposed main cutting elements (220, 240) and each in the In the circumferential direction (198) of the drill head (130), a cutting edge (251, 252, 253, 254) of the at least four cutting edges (251, 252, 253, 254) of the central pyramid (250) is arranged on each adjacent secondary cutting element (210, 230) of the at least two diametrically opposite secondary cutting elements (210, 230).
  2. 2. Drilling tool according to claim 1, characterized in that the at least four cutting edges (251, 252, 253, 254) of the central pyramid (250) are arranged in the circumferential direction (198) of the drill head (130) at associated angles (411, 412, 413, 414) to one another.
  3. 3. Drilling tool according to claim 2, characterized in that the associated angles (411, 412, 413, 414) are of equal size and have 90°.
  4. 4. Drilling tool according to one of the preceding claims, characterized in that each cutting edge (252) of the at least four cutting edges (251, 252, 253, 254) of the central pyramid (250) is arranged at a predetermined angle (401, 501, 601) to a main cutting edge (221) of the at least two diametrically opposed main cutting elements (220, 240).
  5. 5. Drilling tool according to claim 4, characterized in that the predetermined angle (401, 501, 601) is 30°, 45° or 60°.
  6. 6. Drilling tool according to one of the preceding claims, characterized in that the main cutting edges (221, 241) of the at least two diametrically opposite main cutting elements (220, 240), the secondary cutting edges (211, 231) of the at least two diametrically opposite secondary cutting elements (210, 230) and/or the at least four cutting edges (251, 252, 253, 254) of the central pyramid (250) are aligned in the radial direction (299) of the drill head (130).
  7. 7. Drilling tool according to one of the preceding claims, characterized in that the main cutting edges (221, 241) of the at least two diametrically opposite main cutting elements (220, 240), the secondary cutting edges (211, 231) of the at least two diametrically opposite secondary cutting elements (210, 230) and/or the at least four cutting edges (251, 252, 253, 254) of the central pyramid (250) are at least partially straight, curved, convexly curved and/or concavely curved.
  8. 8. Drilling tool according to one of the preceding claims, characterized in that at least one secondary cutting edge (211, 231) of the at least two diametrically opposite secondary cutting elements (210, 230) and/or at least one main cutting edge (221, 241) of the at least two diametrically opposite main cutting elements (220, 240) has a first height (713; 831) on an outer circumference (802) of the drill head (130), wherein the first height (713; 831) is reduced to a second height (833) via a recess (820) in a region facing the central pyramid (250).
  9. 9. Drilling tool according to one of the preceding claims, with a drill shaft (115) having a fastening section (120) for releasable fastening in a tool holder of a hand-held power tool and a spiral-shaped conveyor section (110) for removing drilling dust arising during a machining operation, wherein the drill shaft (115) is connected to the drill head (130) via a material-locking connection.
  10. 10. Drilling tool according to claim 9, characterized in that the fastening section (120) is designed as an SDS shaft.

Description

Description title Drilling tool with a drill head that has a central pyramid State of the art The present invention relates to a drilling tool, in particular a rock drilling tool, with a drill head which has a central pyramid with at least four cutting edges, and at least two diametrically opposed main cutting elements, each with a main cutting edge, and at least two diametrically opposed secondary cutting elements, each with a secondary cutting edge, wherein a secondary cutting element is arranged between two main cutting elements adjacent in the circumferential direction of the drill head. Such a drilling tool designed as a rock drilling tool is known from the prior art. The drilling tool has a drilling head with at least two diametrically opposed main cutting elements, each with a main cutting edge, and at least two diametrically opposed secondary cutting elements, each with a secondary cutting edge. In this case, a secondary cutting element is arranged between two main cutting elements adjacent in the circumferential direction of the drilling head. The drilling head also has a central pyramid with at least four cutting edges. The cutting edges of the central pyramid are congruent with the main cutting edges and the secondary cutting edges in the radial direction and form common cutting edges with them. disclosure of the invention The invention relates to a drilling tool, in particular a rock drilling tool, with a drill head having a central pyramid with at least four cutting edges, as well as at least two diametrically opposed Main cutting elements, each with a main cutting edge and at least two diametrically opposed secondary cutting elements, each with a secondary cutting edge, wherein a secondary cutting element is arranged between two main cutting elements adjacent in the circumferential direction of the drill head. Between each main cutting element of the at least two diametrically opposed main cutting elements and each secondary cutting element of the at least two diametrically opposed secondary cutting elements adjacent in the circumferential direction of the drill head, a cutting edge of the at least four cutting edges of the central pyramid is arranged. The invention thus makes it possible to provide a drilling tool in which the offset arrangement of the cutting edges of the central pyramid relative to the main cutting edges or the secondary cutting edges makes it possible to easily and reliably increase the efficiency of a respective drilling speed, since the material to be machined is machined at several points simultaneously. Preferably, the at least four cutting edges of the central pyramid are arranged at associated angles to one another in the circumferential direction of the drill head. This makes it easy to arrange the cutting edges appropriately. The associated angles are preferably equal and have 90°. This makes it easy and uncomplicated to arrange the cutting edges of the central pyramid symmetrically. Each cutting edge of the at least four cutting edges of the central pyramid is preferably arranged at a predetermined angle to a main cutting edge of the at least two diametrically opposite main cutting elements which is adjacent in the circumferential direction of the drill head. This allows a simple and application-specific arrangement of the cutting edges of the central pyramid relative to the main cutting edges become. Preferably, the predetermined angle is 30°, 45° or 60°. This makes it easy to match the drilling tool to the impact pattern assigned to a corresponding hand-held power tool. It may be expedient to provide a drilling tool, in particular a rock drilling tool, with a drill head having an axis of rotation and at least two diametrically opposed main cutting elements, each with a main cutting edge, and at least two diametrically opposed secondary cutting elements, each with a secondary cutting edge, wherein a secondary cutting element is arranged between two main cutting elements adjacent in the circumferential direction of the drill head. The main cutting edges of the at least two diametrically opposed main cutting elements each have a first maximum height starting from a base side of the drill head, and the secondary cutting edges of the at least two diametrically opposed secondary cutting elements each have a second maximum height starting from the base side of the drill head, wherein the first maximum height and the second maximum height are identical at least within predetermined manufacturing tolerances. The invention thus makes it possible to provide a drilling tool in which hooking during a drilling process, in particular during a drilling process in a reinforcing element, can be efficiently prevented by the maximum heights of the main cutting element and the secondary cutting element being identical at least within predetermined manufacturing tolerances. Furthermore, the triggering of a slip clutch of a hand-held power tool used for the drilling process is at le