EP0048031A2 - Procédé et dispositif pour affûter la pointe d'un foret hélicoidal - Google Patents

Procédé et dispositif pour affûter la pointe d'un foret hélicoidal Download PDF

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Publication number
EP0048031A2
EP0048031A2 EP81107335A EP81107335A EP0048031A2 EP 0048031 A2 EP0048031 A2 EP 0048031A2 EP 81107335 A EP81107335 A EP 81107335A EP 81107335 A EP81107335 A EP 81107335A EP 0048031 A2 EP0048031 A2 EP 0048031A2
Authority
EP
European Patent Office
Prior art keywords
drill
grinding wheel
grinding
axis
cutting edge
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP81107335A
Other languages
German (de)
English (en)
Other versions
EP0048031A3 (en
EP0048031B1 (fr
Inventor
Herbert Diener
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Cessione guehring Automation & Co GmbH
Guehring Automation GmbH
Original Assignee
Gottlieb Guehring KG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Gottlieb Guehring KG filed Critical Gottlieb Guehring KG
Priority to AT81107335T priority Critical patent/ATE15002T1/de
Publication of EP0048031A2 publication Critical patent/EP0048031A2/fr
Publication of EP0048031A3 publication Critical patent/EP0048031A3/de
Application granted granted Critical
Publication of EP0048031B1 publication Critical patent/EP0048031B1/fr
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B3/00—Sharpening cutting edges, e.g. of tools; Accessories therefor, e.g. for holding the tools
    • B24B3/24—Sharpening cutting edges, e.g. of tools; Accessories therefor, e.g. for holding the tools of drills
    • B24B3/26—Sharpening cutting edges, e.g. of tools; Accessories therefor, e.g. for holding the tools of drills of the point of twist drills

Definitions

  • the invention relates to a method for producing a cylindrical jacket point grinding of twist drills according to the preamble of claim 1 and to an apparatus for performing this method according to the preamble of claim 6 and 9 respectively.
  • the drill to be ground is first aligned with its axis to the grinding surface, for example a cup grinding wheel, so that its axis lies in a reference plane perpendicular to the grinding surface and runs inclined to the grinding surface by half the tip angle ⁇ / 2 (see FIG. 1).
  • the drill is fixed in this position by means of a grinding device which runs around a plane that runs in this reference plane and parallel to the grinding surface
  • Cylinder axis which crosses the drill axis at a distance of about a drill diameter from the drill tip, is rotatable.
  • the holder is locked after setting the drill in the sense described above - the distance between the drill axis and the cylinder axis determines the clearance angle of the main cutting edge.
  • the grinding device pivots around the cylinder axis while rotating the grinding wheel and thus creates a cylindrical envelope of the free surface of the drill.
  • the distance between the drill axis and the cylinder axis determines the size of the clearance angle ⁇ at the main cutting edge, which is essentially constant in the cylindrical surface tip grinding over the entire length of the main plane. If this distance became zero, there would be a clearance angle ⁇ (• of 0 °, which would result in a tool that cannot be cut.
  • the invention is therefore an object of the invention to provide a method according to the preamble of claim 1 and a device for performing this method with which drill blanks can be ground in the rotary cycle production process without complicated mechanics, without the bearings and the guides of the grinding wheels -Holder and the grinding wheel can be negatively affected by the grinding movement kinematics.
  • the grinding process with the features of sub-claim 2 is shown to be the least complex. Since the translational relative movement runs parallel to the radial plane of the grinding wheel, this can be provided with a profile which, seen in an axial section of the wheel, forms exactly a sector of a circle which, with displacement of the Grinding wheel or the drill generated the cylindrical surface of the free surface.
  • this contour of the profiling can be produced exactly, it can be seen that this process variant is associated with a certain disadvantage: as can be seen from the geometry of the point grinding, the main cutting edge of the drill must be parallel to the relative movement direction. According to this variant of the method, however, this coincides with the tangent direction of the grinding wheel in the line of contact of the free surface, so that the grinding grooves generated on the free surface run parallel to the main cutting edge. However, this can adversely affect the service life of the cutting edge.
  • the training according to subclaim 3 counteracts this disadvantageous effect. Due to the relative positioning of the relative direction of movement, ie the main cutting edge to the grinding wheel radial plane, the grinding grooves no longer run parallel to the main cutting edge, but rather are inclined at the angle of attack. In this case, the circular sector profile of the grinding wheel must correspond to the oblique cylinder pivoted by the angle of incidence from the normal cylinder section The cut in an ellipse sector can be corrected, but this correction does not represent any additional effort. Because the required profiling results from a simple cylindrical cut, it can be produced in a simple manner by suitable scanning, for example of a cylindrical grinding template.
  • the above-mentioned method can be used to produce a free-surface grinding which has the characteristic of a cone-shaped point grinding, i.e. H. which creates a clearance angle that continuously decreases along the main cutting edge of the drill from the tip to the cutting corner.
  • the device according to subclaim 6 enables the application of this method to drill production with rotary transfer machines.
  • the blank to be manufactured is clamped firmly in a drill holder and positioned opposite the grinding device.
  • the grinding device is aligned so that the main feed movement of the grinding wheel is essentially parallel to the main cutting edge.
  • the clearance angle can be adjusted by moving the cross support on the longitudinal support, the tip angle by swiveling a support plate.
  • the cross support is delivered by moving the longitudinal support in the axial direction of the drill (regrinding a tip).
  • the device according to subclaim 7 enables the simplest form of surface grinding, as defined by the method according to subclaim 2.
  • the method according to the invention can also be implemented with a device in which, according to subclaim 9, it is not the grinding wheel but the workpiece holder which carries out the translational relative movement.
  • This device is particularly useful when the drill is already being pre-processed in another machine and is only to be ground or re-ground in the grinding device.
  • a device is also conceivable in which not the drill holder, but the grinding wheel is provided with a feed drive.
  • the dependent claim 12 is directed to a device which has the particular advantage that a drill point grinding can be produced which has the properties of a cone-shaped point grinding which has particularly favorable properties with regard to the cutting action.
  • Fig. 1 shows a drill 1, the tip of which is provided in a conventional manner by means of a cup-shaped grinding wheel 2 with a cylindrical jacket point grinding.
  • the drill 1 is clamped in a holder, not shown, which is mounted in a frame 5 so as to be pivotable about an axis 4 parallel to the grinding wheel radial plane 3.
  • Fig. 1 shows the drill 1 in the position in which its main cutting edge 6 falls into the grinding wheel radial plane 3, ie at a moment when the pivoting movement of the drill holder about the axis 4 is changing its sign.
  • the half point angle 0/2 can be selected by inclining the holder or drill axis la to the grinding wheel radial plane 3.
  • the constant clearance angle ⁇ in this method over the entire main cutting edge 6 is ensured in that the cylinder jacket Z described by the main cutting edge 6 during the pivoting movement of the drill holder has a radius r which is greater than the distance D between the axis of rotation 4 and the grinding wheel 2 Sizes D and r essentially correspond to the drill diameter and the clearance angle ⁇ can be varied by adjusting the distance A between the drill axis la and the cylinder axis 4 (FIG. La). 1, when the drill 1 is turned upwards out of the plane of the drawing, the grinding wheel 2 creates one of the visible free surface 7a opposite, not recognizable free area 7b, which coincides with the indicated cylinder jacket Z. To grind the second free surface 7a, the drill 1 is rotated through 180 ° in the holder.
  • FIG. 2 and 3 show a drill 1 which is ground in the method according to the invention.
  • the main cutting edge 6 runs parallel to the translation relative movement direction T.
  • the drill axis la is inclined at a certain angle 0/2 to the translation movement direction T. This angle ⁇ / 2 corresponds to half the apex angle ⁇ of the drill 1.
  • the position of the main cutting edge 6 and the drill axis la is fixed in the state shown via a bracket (not shown), and the grinding wheel 2 or the drill 1 is moved by one while the grinding wheel is running 2 vertical axis translationally moved in the direction of arrow T.
  • Fig. 3 it can be seen that the drill axis la runs parallel to a plane perpendicular to the grinding wheel axis.
  • the main cutting edge 6 is represented as a point, and the free surface 7b as a circular sector 10 of a grinding wheel profiling 11.
  • the free surface 7b is produced in that the grinding wheel 2 and the drill 1 perform a translational relative movement T to one another in a direction parallel to the tangential plane 9 at the point of contact between the grinding wheel 2 and the main cutting edge 6, whereby the circular sector 10 generates the cylinder jacket Z of the free surface 7b.
  • the clearance angle ⁇ of the main cutting edge By parallel displacement of the drill axis la in the direction of arrow V ⁇ , the clearance angle ⁇ of the main cutting edge, by pivoting the drill axis la in the plane of the drawing in FIG. 2 according to arrow V 6, the tip angle ⁇ , and by twisting of the drill 1 about its axis la according to the arrow V W , the cross-cutting angle 1 P can be varied.
  • the drill is rotated through 180 ° about its axis.
  • the geometrical relationships in this grinding method can best be seen from FIGS. 4 to 6.
  • the cylinder jacket Z which creates the free surface 7b is shown as a dash-dotted line. 6 is in the position in which it is also shown in FIG. 3.
  • the grinding wheel 2 is arranged rotatably about a grinding wheel axis 2a and is displaced relative to the drill 1 in the direction of the main cutting edge 6, as a result of which the free surface 7b is generated. Otherwise, the setting variation options according to FIGS. 2 and 3 apply.
  • a grinding wheel 2 ' can be used, the axis 2a' of the axis 2a of which is pivoted by a certain angle of attack ⁇ about an axis perpendicular to the plane of the drawing in accordance with FIG. 5, so that the grinding marks are then no longer parallel to the main cutting edge 6 but at an angle lp inclined to her.
  • the profiling must then be corrected in accordance with the indicated cylindrical cut S, so that a new grinding wheel 2 'is required, the profiling 11' of which is formed by an ellipse 10 ', which represents a portion of the cut cylinder jacket Z'.
  • the grinding wheel axis 2a ' is pivoted, the grinding wheel must of course be made wider, as is shown in FIG. 7.
  • the grinding wheel 2 'shown in FIG. 7 coincides with the grinding wheel 2 in the view according to FIG. 6.
  • FIG. 8 shows a grinding wheel 2 'with an elliptical profile 11' in an axial section.
  • the grinding wheel 2 ' rotates about its axis 2a', which is pivoted by an angle of attack ⁇ in the above sense from its orientation perpendicular to the translation-relative movement direction T.
  • the translation-relative movement direction T runs essentially parallel to the plane of the drawing in FIG. 8 and thus parallel to the main cutting edge, as can also be seen in FIG. 9.
  • FIG. 10 shows an embodiment of an apparatus for carrying out the method described above.
  • This device is particularly suitable when the drill 1 is manufactured in rotary cycle processing machines.
  • the drill 1 is clamped in a drill holder 20 which is mounted on a rotary indexing table 21.
  • the grinding station 22 executing the grinding work cycle has a longitudinal support 23 aligned with the drill holder 20, which can carry out an infeed movement, and a transverse support 24, which can be moved transversely to the longitudinal support 23.
  • the longitudinal support 23 carries a holder 25 which supports the drill tip.
  • a support plate 26 is pivotally mounted in the transverse support 24, the pivot axis 27 of which vertically intersects the extended drill axis la.
  • the tip angle 0 is set by pivoting the support plate 26.
  • a feed slide 27 is arranged displaceably on the support plate 26, the feed direction representing the relative translation direction T referred to above.
  • the feed carriage 27 carries a grinding wheel holder 28 which is height-adjustable to compensate for the wear of the grinding wheel and which has a holder corresponding to FIGS. 2, 3 and 6 carries profiled grinding wheel 2, the axis of rotation of which is perpendicular to the drawing plane of FIG. 10.
  • the grinding wheel 2 touches - as viewed in the direction of arrow T - the drill 1 as shown in FIG. 3 .
  • the clearance angle ⁇ can be varied by shifting the transverse support 24.
  • the grinding wheel holder 28 is fastened on the feed slide 27 in such a way that it can be pivoted about an axis of rotation D ⁇ essentially passing through the drill axis and running perpendicular to the support plate 26, then a free-surface grinding can be produced, the grinding grooves of which are inclined to the main cutting edge 6 by the adjustable pivoting angle le run.
  • FIG. 11 shows such an expanded device, which essentially corresponds to the device according to FIG. 10 and is shown viewed parallel to the axis of rotation D ⁇ .
  • the grinding wheel holder 28 which is pivotally and adjustably mounted on the feed slide 27 and on which the grinding wheel bearing 29 is guided. Similar to the support plate 26 in FIG. 10, the grinding wheel holder 28 can be pivoted about a link guide 31 into which bolts 32 can be pivoted about the axis of rotation D ⁇ described above. The before the direction of thrust is marked with the arrow T.
  • a motor 30 drives a grinding wheel 2 'profiled according to FIGS. 7 to 9, the axis 2a' of which is pivoted by an angle ⁇ with respect to the position shown in FIG. 10. Accordingly, the grinding wheel 2 'is provided with an elliptical profile 11', viewed in axial section, the contour of which, viewed in the direction of the feed T, forms a circular sector which generates the cylinder jacket Z.
  • FIG. 12 shows a further device for carrying out the grinding method described above. It is not the grinding wheel 2 but the drill holder that carries out the translational relative movement in the direction of the arrow T.
  • This device shown in FIG. 12 can be retrofitted to surface grinding machines with little effort.
  • a machine frame 40 carries a grinding wheel 2 or 2 ', so that its grinding wheel axis 2a' is aligned horizontally.
  • a machine bed 41 receives a horizontally aligned support support 42, which via corresponding horizontal guides, for. B. 43 is pivotable and adjustable about a vertical axis.
  • the adjustment support 42 carries a feed slide 44 which can be displaced along the adjustment support 42 by means of a drive unit 45.
  • a drill holder 46 is mounted in the feed carriage 44 so as to be pivotable and adjustable about an axis perpendicular to the adjustment support 42. The drill holder 46 receives the drill 1.
  • the adjustment support 42 defines the angle of attack ⁇ , which of the Contour of the grinding wheel profile must be adjusted.
  • the adjustment support 42 can also be rigidly attached to the machine bed 41, and the grinding wheel can be mounted in the frame 40 so as to be pivotable about a vertical axis, in order to be able to implement the method described above.
  • the drill holder can be provided with a rotary drive around the drill axis or via a further one. speaking pivoting mechanism in the grinding unit, the pivot axis should then coincide with the main cutting edge of the drill.
  • the tip of the drill can be provided with a bevel, the clearance angle of which varies over the main cutting edge of the drill.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
EP81107335A 1980-09-17 1981-09-16 Procédé et dispositif pour affûter la pointe d'un foret hélicoidal Expired EP0048031B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81107335T ATE15002T1 (de) 1980-09-17 1981-09-16 Verfahren und vorrichtung zur erzeugung eines spiralbohrer-spitzenanschliffs.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3035099 1980-09-17
DE3035099A DE3035099C2 (de) 1980-09-17 1980-09-17 Verfahren und Vorrichtung zur Erzeugung eines Zylindermaterial-Spitzenanschliffs von Spiralbohrern

Publications (3)

Publication Number Publication Date
EP0048031A2 true EP0048031A2 (fr) 1982-03-24
EP0048031A3 EP0048031A3 (en) 1982-07-14
EP0048031B1 EP0048031B1 (fr) 1985-08-21

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EP81107335A Expired EP0048031B1 (fr) 1980-09-17 1981-09-16 Procédé et dispositif pour affûter la pointe d'un foret hélicoidal

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EP (1) EP0048031B1 (fr)
AT (1) ATE15002T1 (fr)
DE (1) DE3035099C2 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61279454A (ja) * 1985-06-01 1986-12-10 Toa Kikai Seisakusho:Kk ドリル研削盤
JPH0743109U (ja) * 1990-12-15 1995-08-18 株式会社東亜機械製作所 シンニング用ドリル研削盤
CN112571269A (zh) * 2019-09-27 2021-03-30 卡迪尔生产有限责任公司 珩磨机器
CN120619934A (zh) * 2025-07-09 2025-09-12 深圳数马电子技术有限公司 螺旋面钻尖的后刀面磨削方法及数控设备

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3039649C2 (de) * 1979-04-18 1983-12-08 Karl 7539 Kämpfelbach Reiling Vorrichtung zum Schleifen der Schneiden von Spiralbohrern

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1064892A (en) * 1965-03-17 1967-04-12 Brierley Zachry A method of and a machine for grinding twist drill points
DD113713A1 (fr) * 1974-08-23 1975-06-20

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61279454A (ja) * 1985-06-01 1986-12-10 Toa Kikai Seisakusho:Kk ドリル研削盤
JPH0743109U (ja) * 1990-12-15 1995-08-18 株式会社東亜機械製作所 シンニング用ドリル研削盤
CN112571269A (zh) * 2019-09-27 2021-03-30 卡迪尔生产有限责任公司 珩磨机器
CN112571269B (zh) * 2019-09-27 2023-08-15 卡迪尔生产有限责任公司 珩磨机器
US12030155B2 (en) 2019-09-27 2024-07-09 Kadia Produktion Gmbh + Co. Honing machine
CN120619934A (zh) * 2025-07-09 2025-09-12 深圳数马电子技术有限公司 螺旋面钻尖的后刀面磨削方法及数控设备

Also Published As

Publication number Publication date
EP0048031A3 (en) 1982-07-14
DE3035099A1 (de) 1982-03-25
EP0048031B1 (fr) 1985-08-21
ATE15002T1 (de) 1985-09-15
DE3035099C2 (de) 1985-11-28

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