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EP-4737038-A1 - DRILL, DRILLING SYSTEM, DRILLING METHOD AND USE OF A DRILL

EP4737038A1EP 4737038 A1EP4737038 A1EP 4737038A1EP-4737038-A1

Abstract

A drill (1) is provided, extending from a first end (3a) to a second end (3b) along a longitudinal axis (X) and comprising a cutting tip (7) at the first end (3a) and a shaft (5) extending from the cutting tip (7) towards the second end (3b),the cutting tip (7) comprising at least one cutting edge (11) located at the first end (3a) and a flute (13) extending from the cutting edge (11) towards the second end (3b), and the shaft (5) comprising a circumferentially enclosed discharge channel (31) connecting to the flute (13) at a side away from the cutting edge (11), extending towards the second end (3b) and terminating in a discharge opening (37) in an outer circumference of the shaft (5) for discharging swarf generated by the cutting edge (11), a pressurized gaseous medium supply channel having a supply opening for receiving a pressurized gaseous medium and extending from the supply opening towards the first end (3a), the supply opening located closer to the second end (3b) as the discharge opening (37), and an injection channel extending between an inflow opening connected to the pressurized gaseous medium supply channel and an injection opening connected to the discharge channel (31), wherein the injection channel is configured to inject the pressurized gaseous medium through the injection opening into the discharge channel (31) in an injection direction towards the second end (3b), thereby creating a vacuum at the first end (3a).

Inventors

  • Olesen, Brian Svane
  • Wulff, Michael Bank
  • Thomsen, Tyge Roslin
  • Jensen, Boris

Assignees

  • KYOCERA UNIMERCO TOOLING A/S

Dates

Publication Date
20260506
Application Date
20241105

Claims (15)

  1. A drill (1, 101, 201), extending from a first end (3a) to a second end (3b) along a longitudinal axis (X) and comprising a cutting tip (7, 107) at the first end (3a) and a shaft (5, 105, 205) extending from the cutting tip (7, 107) towards the second end (3b), the cutting tip (7, 107) comprising at least one cutting edge (11) located at the first end (3a) and a flute (13) extending from the cutting edge (11) towards the second end (3b), and the shaft (5, 105, 205) comprising a circumferentially enclosed discharge channel (31, 131) connecting to the flute (13) at a side away from the cutting edge (11), extending towards the second end (3b) and terminating in a discharge opening (37, 137) in an outer circumference of the shaft (5, 105, 205) for discharging swarf generated by the cutting edge (11), a pressurized gaseous medium supply channel (51, 151) having a supply opening (53, 153) for receiving a pressurized gaseous medium and extending from the supply opening (53, 153) towards the first end (3a), the supply opening (53, 153) located closer to the second end (3b) as the discharge opening (37, 137), and an injection channel (55, 155) extending between an inflow opening (57, 157) connected to the pressurized gaseous medium supply channel (51, 151) and an injection opening (59, 159) connected to the discharge channel (31, 131), wherein the injection channel (55, 155) is configured to inject the pressurized gaseous medium through the injection opening (59, 159) into the discharge channel (31, 131) in an injection direction (I) towards the second end (3b), thereby creating a vacuum at the first end (3a).
  2. The drill (1, 101, 201) according to claim 1, wherein, when a distance from a point (P) at which the longitudinal axis (X) intersects the first end (3a) to the injection opening (59, 159) is indicated as d, and, when viewed in a cross-section of the shaft (5, 105, 205) perpendicular to the longitudinal (X) axis and intersecting the injection opening (59, 159), a maximum outer diameter of the shaft (5, 105, 205) is indicated as D, a ratio of D/d is in a range of 0,5 to 1,5, preferred in a range of 0,7 to 1,2, and further preferred in a range of 0,8 to 1,0.
  3. The drill (1, 101, 201) according to claim 1 or 2, wherein an angle (α) formed between the longitudinal axis (X) and the injection direction (I) is in a range of 5° to 85°, preferred in a range of 10° to 60°, and further preferred in a range of 15° to 30°.
  4. The drill (1, 101, 201) according to anyone of the preceding claims, wherein, when viewed in a cross-section of the injection channel (55, 155) perpendicular to the injection direction (I), a minimum cross-sectional area of the injection channel (55, 155) is indicated as a, and, when viewed in a cross-section of the shaft (5, 105, 205) perpendicular to the longitudinal axis (X) and intersecting the injection opening (59, 159), a cross-sectional area of the discharge channel (31, 131) is indicated as A, a ratio of A/a is in a range of 5 to 20, preferred in a range of 4 to 15, and further preferred in a range of 3 to 10.
  5. The drill (1) according to anyone of the preceding claims, wherein the cutting tip (7) is separate from the shaft (5) and attachable to shaft (5).
  6. The drill (1) according to anyone of the preceding claims, wherein the shaft (5) comprises a tubular body having the discharge channel (31) formed as its hollow interior and enclosed by a circumferential wall (33) of the shaft (5), and the pressurized gaseous medium supply channel (51) and the injection channel (55) are formed in the wall (33).
  7. The drill (101, 201) according to anyone of claims 1 to 5, wherein the shaft (105, 205) is a drill bit including a flute (115) connected to the flute (13) of the cutting tip (107) at a side away from the cutting edge (11) and extending towards the second end (3b) in the form of a helix, the flute (115) of the shaft (105, 205) forming the discharge channel (131), the drill (101, 201) further comprises an elongated sleeve (171; 271) configured to accommodate the shaft (105, 205) in its hollow interior, the sleeve (171, 271) having a radial opening (173) at one end penetrating a circumferential wall (175) of the sleeve (171, 271) and an axial opening (177) at the other end, wherein, when the shaft (105, 205) is accommodated in and fixed to the sleeve (171, 271), the cutting tip (7, 107) protrudes from the axial opening (177) of the sleeve (171, 271), the discharge channel (131) is radially delimited by the circumferential wall (175) of the sleeve (171, 271) and the discharge opening (137) of the shaft (105, 205) and the radial opening (173) of the sleeve (171, 271) overlap with one another so as to discharge swarf generated by the cutting edge (11).
  8. The drill (101, 201) according to claim 7, wherein the pressurized gaseous medium supply channel (151) is formed along a straight line in the web of the shaft (105, 205) or is formed along a helix following a corresponding land (181) of the flute (115) of the shaft (105, 205).
  9. The drill (101, 201) according to claim 7 or 8, wherein the injection channel (155) is formed as a trough in the outer circumference of the shaft (105, 205) and radially delimited by the circumferential wall (175) of the sleeve (171, 271).
  10. The drill (1, 101, 201) according to anyone of the preceding claims, wherein the shaft (5, 105, 205) is a 3D printed body, optionally a 3D printed and sintered metal body.
  11. A drilling system (1000), including a drill (1, 101, 201) according to anyone of the preceding claims, a drilling device (1100) configured for rotating and translating the drill (1, 101, 201), and a pressurized gaseous medium source (1200) connected to the supply opening (53, 153) and configured for supplying a pressurized gaseous medium to the drill (1, 101, 201) and adjusting a flow rate of the pressurized gaseous medium so that a vacuum is created at the first end (3a) of the drill (1, 101, 201).
  12. The drilling system (1000) of claim 11, further including an oscillation device connected to the drill (1, 101, 201) and configured for oscillating the drill (1, 101, 201) along the longitudinal axis, thereby adjusting the size of the swarf generated during cutting, and/or the drilling system (1000) further comprising a vacuum source (1300) connected to the discharge opening (37, 137) or the radial opening (173) and configured for applying a vacuum.
  13. Use of the drill (1, 101, 201) according to anyone of claims 1 to 10 and/or use of the drilling system (1000) according to anyone of claims 11 and 12 for drilling of metal, fiber reinforced plastics, and/or composites thereof, and/or for drilling a through hole opening into a blind cavity, for example a through hole having a diameter equal to or less than 40 mm.
  14. A drilling method, comprising the steps of rotating the drill (1, 101, 201) according to anyone of claims 1 to 10 and supplying a pressurized gaseous medium to the supply opening (53, 153) of the drill (1, 101, 201), so that a vacuum is created at the first end (3a) of the drill (1, 101, 201), thereby removing swarf generated by the cutting edge (11) from the cutting tip (7, 107).
  15. The drilling method according to claim 14, wherein, when the drill (1, 101, 201) is translated into the work piece for drilling, the drill (1, 101, 201) is oscillated along its longitudinal axis (X).

Description

Technical Field The present invention relates to a drill, a drilling system, a drilling method and use of a drill, and in particular to a drill using pressurized gaseous medium to create a vacuum at the drill tip thereby discharging swarf generated during the drilling. Background Drilling holes in materials like metal, plastics, wood, fiber reinforced plastics, composites thereof, etc. is a well-known manufacturing technique in various applications like mechanical engineering, aeronautical engineering, automotive engineering, etc. Conventional drilling is carried out with drills having a shank and a drill body with a cutting tip and flutes as means for transporting swarf created at the cutting tip away from the cutting tip and out of the drilled hole. During swarf transport, the swarf will be moved away from the cutting tip with the help of the flutes and a cylindrical enclosure, e.g. formed by the walls of the drilled hole. The created swarf may have various forms depending on the material being drilled. Metallic and plastic materials will often produce long curly swarf, whereas e.g. fiber reinforced plastics will often produce dust. In any case, the drilling process will leave particles of the drilled material which may contact and/or attach to the wall of the drilled hole, resulting in a drilling process which will potentially produce a hole with limited accuracy and a coarse surface roughness. Furthermore, in the conventional drilling, often some residual swarf remains in the drilled hole and has to be removed manually. Further and in case of layered materials, the generated swarf might penetrate into interfaces between material layers, thereby promoting contamination of the material, or in case of drilling into blind cavities, the swarf might become trapped in the cavity thereby creating contamination therein. Thus, in the conventional drilling, to circumvent said issues, additional processing of the drilled holes and/or extensive cleaning of said cavities or layer interfaces has to be carried out. Thus, there remains a need in the conventional drilling processes to enhance swarf removal from the drilled hole with less exposure of the drilled hole to the swarf. Brief Summary In order to solve the above problem, the present disclosure provides a drill with the features according to claim 1, a drilling system with the features according to claim 11, use of a drill with the features according to claim 13 and a drilling method with the features according to claim 14. Further preferred embodiments of the drill, the drilling system and the drilling method are described in the respective dependent claims. That is, a drill is provided, extending from a first end (e.g. cutting end) to a second end (e.g. attachment end, e.g. attachable to a drill chuck of a drilling machine) along a longitudinal axis and comprising a cutting tip at the first end and a shaft extending from the cutting tip towards the second end, the cutting tip comprising at least one (e.g. integral) cutting edge (e.g. 2, 3, 4 or more) located at the first end and a flute (e.g. in the same quantity as the cutting edges) extending from the cutting edge towards the second end, and the shaft comprising a circumferentially enclosed discharge channel (e.g. in a cross-section of the drill perpendicular through the longitudinal axis fully enclosed, e.g. by a circumferential wall of the shaft or a circumferential wall of an additional elongated sleeve (e.g. cylindrical body) disposed around the shaft) connecting to the flute at a side away from the cutting edge (e.g. 2, 3, 4 or more discharge channels, e.g. in the same quantity as the flutes), extending towards the second end and terminating in a (e.g. radial) discharge opening in an outer circumference of the shaft for discharging swarf (e.g. chips, dust, etc.) generated by the cutting edge, a pressurized gaseous medium supply channel (e.g. 2, 3, 4 or more pressurized gaseous medium supply channels; the pressurized gaseous medium supply channel may define a flow path via a single or branching bore, a sponge-like structure, a honeycomb structure, etc.) having a supply opening for receiving a pressurized gaseous medium (e.g. having a higher pressure as compared to the atmospheric pressure at the cutting tip, the pressurized gaseous medium being e.g. pressurized air, pressurized nitrogen, etc. and optionally containing a minimal amount of lubrication liquid, e.g. cutting oil) and extending from the supply opening towards the first end, the supply opening located closer to the second end as the discharge opening, and an injection channel (e.g. 2, 3, 4 or more injection channels) extending between an inflow opening connected to the pressurized gaseous medium supply channel and an injection opening connected to the discharge channel (e.g. more than one injection channel is connected to one discharge channel and/or more than one injection channel is connected to the pressurized gaseous medium supply channel),