EP0143870B1 - Dispositif auxiliaire pour l'affûtage de forets hélicoidaux - Google Patents

Dispositif auxiliaire pour l'affûtage de forets hélicoidaux Download PDF

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Publication number
EP0143870B1
EP0143870B1 EP84103750A EP84103750A EP0143870B1 EP 0143870 B1 EP0143870 B1 EP 0143870B1 EP 84103750 A EP84103750 A EP 84103750A EP 84103750 A EP84103750 A EP 84103750A EP 0143870 B1 EP0143870 B1 EP 0143870B1
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EP
European Patent Office
Prior art keywords
drill
grinding
auxiliary device
polyhedron body
main cutting
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.)
Expired
Application number
EP84103750A
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German (de)
English (en)
Other versions
EP0143870A1 (fr
Inventor
Robert Wolff
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to AT84103750T priority Critical patent/ATE31655T1/de
Publication of EP0143870A1 publication Critical patent/EP0143870A1/fr
Application granted granted Critical
Publication of EP0143870B1 publication Critical patent/EP0143870B1/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
    • B24B3/247—Supports for drills

Definitions

  • the invention relates to an auxiliary device for regrinding the tip angle and the clearance angle of twist drills, consisting of a polyhedron body, which has a receiving channel for clamping the twist drill and two table support surfaces symmetrically inclined to the axis of the clamped twist drill and for grinding one or the other main cutting edge of the twist drill with the one or another table support surface is placed on a table perpendicular to the grinding plane.
  • the table contact surfaces of the polyhedron body are each inclined by half the complementary angle of the tip angle with respect to the axis of the clamped drill so that, with a corresponding rotational orientation of the twist drill, its main cutting edges with respect to the tip angle can be reground, with the polyhedron body being placed on the table for grinding one main cutting edge with one table support surface and for cutting the other main cutting edge with the other table support surface.
  • the grinding table has a pivot bearing journal which is arranged near the grinding plane and projects upwards and engages in an associated bearing bore in the polyhedron body provided on each table bearing surface.
  • the cutting edges are given the required clearance angle or relief grinding. Since in the known auxiliary device the distance between the grinding plane or grinding wheel and the pivot pin is fixed, the polyhedron body must first be plugged onto the pivot pin, after which the final alignment and tightening of the twist drill in the polyhedron body can take place. When aligning, it must be ensured on the one hand that a main cutting edge lies against the grinding wheel and on the other hand that the two main cutting edges adopt the required diametrical or rotary alignment. Aligning and tightening the twist drill in this way is cumbersome and time-consuming in practice. In addition, the twist drill protrudes relatively far out of the polyhedron body, so that vibration-free fixed tension is critical.
  • auxiliary device for regrinding twist drills in which the twist drill is inserted into a channel piece which is gripped by hand, the twist drill being held in the channel with the thumb.
  • the gutter section is chamfered at the front end in a roof shape with the tip angle of the drill bit, the bevels forming visible edges that are several times longer than the main cutting edges of the drill bit.
  • the channel section is pivoted more or less far upwards around its lower front edge, although the clearance angle can only be ground inaccurately.
  • the twist drill must be rotated through 180 ° in the groove to grind the second cutting edge. Holding the twist drill with a thumb turns out to be very critical, since a certain twisting or slipping back of the twist drill can hardly be avoided. This is particularly the case when a severely blunted twist drill is to be reground, since the drill often gets so hot that it can hardly be held by hand.
  • US-A-2595950 discloses an auxiliary device for regrinding tool cutting edges, which consists of a polyhedron body, which is provided with a plurality of symmetrical table support surfaces which are opposed in pairs and which has a receiving channel for clamping the tool.
  • the polyhedron body is assigned to a grinding device in which the grinding plane or the tangential plane through the grinding point is arranged parallel to the grinding table plane.
  • the table support surfaces of the polyhedron body are inclined relative to the table plane or grinding plane in such a way that the tool is at a solid angle to the grinding plane, i. H. that is, in two mutually perpendicular planes.
  • One of the inclinations could be used here for grinding to maintain the tip angle of a twist drill and the other inclination to maintain the clearance angle.
  • the grinding table must be vertically adjustable perpendicular to the grinding plane or the tool must be set in abutment against the grinding wheel with the polyhedron body lying on the table, with its two cutting edges simultaneously having to be rotated before the tool is finally firmly clamped in the polyhedron body can be. This in turn requires laborious and time-consuming alignment work.
  • do-it-yourselfers are generally not available where the grinding plane and grinding table are parallel to one another.
  • the invention has for its object to provide an inexpensive auxiliary device for regrinding twist drills, which is easier to use and requires no special facilities on the grinding table.
  • the table support surfaces are inclined by the clearance angle with respect to the drill axis, that the polyhedron body at the outlet end for the drill tip is chamfered with the tip angle and has stitch edges that run parallel to the main cutting edges of the drill and are several times longer than the main cutting edges are that the alignment and clamping of the twist drill can be carried out with the polyhedron body removed from the grinding table and that the polyhedron body can be displaced by hand on the grinding table perpendicularly to the grinding plane.
  • the great advantage of the auxiliary device according to the invention is that the twist drill can now be clamped onto the polyhedron body completely independently of the structure of the grinding device.
  • the polyhedron body is held in one hand, the twist drill is inserted into its receiving channel until its tip protrudes a sufficient distance far above the polyhedron body. Then the two main cutting edges are aligned parallel to the table support surfaces and the twist drill is finally clamped in the polyhedron body. Thereafter, the polyhedron body clamped to the twist drill is placed on the grinding table with one of its table support surfaces, the clearance angle being exactly predetermined by the inclination of the table support surfaces relative to the axis of the clamped drill.
  • the polyhedron body can now be freely moved on the grinding table, and the required alignment with respect to the tip angle is now carried out using the front visible edges of the polyhedron body.
  • the twist drill is placed in this orientation by means of a purely translatory displacement against the grinding body, it now being possible to exert a high contact pressure. After grinding one main cutting edge, turning the auxiliary device by 180 ° is sufficient to grind the second main cutting edge in the same way. Because of its construction from only a few parts, such an auxiliary device can be manufactured extremely inexpensively.
  • the polyhedron body can consist of two clamping jaws, essentially divided along the drill receiving channel.
  • This split embodiment of the polyhedron body saves a separate, complex clamping device for the drill, which is advantageous both in terms of production and in terms of handling.
  • one of the clamping jaws can have a screwing pin which engages in the other clamping jaws and is provided with a threaded bore and which is provided with a passage for the drill.
  • the clamping screw can be accessible from the side area of the auxiliary device for clamping the two clamping jaws together. Since this side area does not come into contact with the grinding table, grinding wheel or the like, the screw head can be designed as an easy-to-use rotary handle. The top and bottom can be retained as full contact areas.
  • the two clamping jaws can be provided with positively interlocking guide lugs and associated receptacles.
  • these guide lugs and receptacles ensure exact guidance of the two polyhedron halves to one another, so that the flatness, i. H. the tilting freedom of the auxiliary device, the contact surfaces is guaranteed.
  • Such guide devices are necessary because the spiral shape of the secondary cutting edges can result in a slight displacement of the two clamping jaws against one another when clamping a drill.
  • the polyhedron body can be in one piece and have a transverse channel for a clamping screw opening into the drill receiving channel.
  • This embodiment variant is particularly favorable in terms of production.
  • the locking screw should be made of soft metal or plastic.
  • the side surfaces of the polyhedron body can be designed as contact surfaces for a guide stop on the grinding table side.
  • the formation of the side surfaces as contact surfaces for a guide stop is advantageous when extreme demands are placed on the accuracy of the tip angle, and especially when a large number of drills are to be reground. In the latter case, a single alignment of the guide stop on the grinding table side is sufficient to always achieve an exact tip angle.
  • Fig. Shows an auxiliary device 1 with an inserted drill 2, which rests on a grinding table 3.
  • the drill tip 4 is placed on the peripheral surface of a grinding wheel 5.
  • the auxiliary device 1 is designed as a polyhedron body 6 and consists of two clamping jaws 7, 8.
  • the end faces 9, 10 of the clamping jaws 7, 8 lying at the outlet end 11 for the drill tip 4 are beveled and form visible edges 12, 13, each parallel to one of the two cutting edges 14, 15 run.
  • the visible edges 12, 13 are chamfered in such a way that the drill axis 16 is brought to the grinding wheel 5 at an angle a of 30 °. This results in a usual tip angle ⁇ at the drill tip 4 of 120 °; see. also Fig. 5.
  • Fig. Shows the auxiliary device 1, the underside 18 formed as a support surface 17 on the Grinding table 3 rests.
  • the contact surface 17 is inclined by the clearance angle y with respect to the drill axis 16, so that the main cutting edge 14 (not visible here) is given a corresponding clearance angle y.
  • the clearance angle y has a common size of 6 °; in principle, other clearance angles are also conceivable for special cases such as hard metal cutting or the like.
  • the top side 19 of the auxiliary device 1 is also designed as a support surface 20 and is inclined in the same way by the clearance angle y with respect to the drill axis 16. To grind the main cutting edge 15, it is therefore sufficient to turn the auxiliary device 1 through 180 ° and now to align it with the visible edge 12.
  • the exact clamping of the drill 2 in the auxiliary device 1 is facilitated by markings 21, on which the main cutting edges 14, 15 are aligned and thus receive a horizontal orientation.
  • the drill 2 in the two-part embodiment of the auxiliary device 1 is inserted into a receiving channel 22, which is formed from two V-grooves 23, 24, each of which is assigned to a clamping jaw 7, 8.
  • the clamping jaw 7 has a threaded pin 26 provided with a threaded bore 25, which is provided with a passage 27 for the drill 2.
  • the drill 2 can now be clamped in the receiving channel 22 via the clamping screw 28. Since the tensioning screw 28 can be operated from the side surface 29, the head of the tensioning screw 28 can be designed as a hand grip 30.
  • the clamping jaws 8 is provided with a receptacle 31 for the screwing pin 26 designed as a guide projection 32, so that the two clamping jaws 7, 8 cannot move against one another.
  • the auxiliary device 1 made of a soft material such. B. plastic
  • FIG. 4 shows an auxiliary device 37 which is designed as a one-piece polyhedron body 38.
  • the drill 2 lies here in a receiving channel 39 with a diamond-shaped cross section and is tightened by a clamping screw 40 which is screwed into a transverse channel 41. Otherwise, the same geometric conditions apply to the polyhedron body 38 as for the polyhedron body 6.
  • the auxiliary device 37 it is otherwise irrelevant if the drill axis 16 is somewhat off-center in the case of smaller or larger drill diameters, since this results in the geometrical orientation specifications by the polyhedron body 38 do not change.
  • the side surfaces 29, 42 of the auxiliary device 1 or the side surfaces 43, 44 of the auxiliary device 36 are designed as contact surfaces 45, 46 or 47, 48 for a guide stop 49 on the grinding table side, indicated by dash-dotted lines in FIG. And FIG. 3 . If a large number of drills 2 are to be reground, it is sufficient in this case to z. B. to place the auxiliary device 1 with its end face 10 on the grinding wheel 5 and to fix the guide stop 49 on the basis of this orientation. Then all the drills can then be ground exactly by simply placing the auxiliary device 1 on the guide stop 49.
  • Fig. Shows a drill tip 4 with the main cutting edges 14, 15 and the spiral secondary cutting edges 50, 51.
  • the main cutting edges 14, 15 together form the tip angle ⁇ .
  • a free surface 52 can be seen behind the main cutting edge 15, as is created by grinding at the clearance angle y. While with a drill with a diameter of less than 6 mm, a simple grinding under the clearance angle y is sufficient, with larger drill diameters it is advantageous to provide an additional relief surface 53.
  • This relief surface 53 can also be produced with the auxiliary devices 1 and 37 without any problems.
  • the drill 2 is then rotated in the receiving channel 22 or 39 in the arrow direction 54 shown in FIG. 2 by approximately 15 ° , so that the orientation of the main cutting edges 14, 15 no longer coincides with the markings 21.
  • the relief grinding surface 53 is then created by lightly grinding again.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
  • Drilling Tools (AREA)

Claims (6)

1. Appareil auxiliaire pour le remeulage de l'angle de pointe (Φ) et l'angle de dépouille (y) de forets hélicoïdaux (2), constitué d'un corps polyédrique (6), qui possède un canal porte-outil (22) pour serrer le foret et deux surfaces d'appui d'établi (17, 18), inclinées symétriquement par rapport à l'axe (16) du foret serré et qui est appliqué sur un établit (3) perpendiculaire au plan de meulage par l'une ou l'autre des surfaces d'appui (17 ou 18) pour le meulage de l'une ou l'autre des arêtes principales (14, 15) du foret (2), caractérisé par le fait que les surfaces d'appui d'établi (17, 18) sont inclinées, par rapport à l'axe de foret (16), de l'angle de dépouille (y), que le corps polyédrique (6), à l'extrémité de sortie (11) de la pointe de foret (4), est biseauté, en forme de toit, avec l'angle de pointe (Φ), et possède des faces de visée (12, 13) s'étendant parallèlement aux arêtes principales (14, 15) du foret (2) et qui sont d'une longueur multiple de celle des arêtes principales (14, 15); l'alignement et le serrage du foret (2) peut s'effectuer alors que le corps polyédrique (6) est écarté de l'établi de meulage (3) et le corps polyédrique (6) est déplaçable en translation à la main, perpendiculairement au plan de meulage, sur l'établi de meulage (3).
2. Appareil auxiliaire selon la revendication 1, caractérisé par le fait que le corps polyédrique (6) est constitué de deux mâchoires de serrage (7, 8), séparées sensiblement le long du canal porte-foret (22).
3. Appareil auxiliaire selon la revendication 2, caractérisé par le fait que l'une des mâchoires de serrage (7) possède un tenon de vissage (26) muni d'un alésage fileté (25) et s'engageant dans l'autre mâchoire (8), tenon qui présente un passage (27) pour le foret (2).
4. Appareil auxiliaire selon l'une des revendications 1 à 3, caractérisé par le fait que les deux mâchoires de serrage (7, 8) sont munies d'épaulements de guidage (32, 36) et surfaces associées (31, 33) qui viennent en prise les unes avec les autres du fait de leur forme.
5. Appareil auxiliaire selon la revendication 1, caractérisé par le fait que le corps polyédrique (38) est d'une seule pièce et possède un canal transversal (41) pour une vis de blocage (40), qui débouche dans le canal porte-foret (39).
6. Appareil auxiliaire selon l'une des revendications 1 à 5, caractérisé par le fait que les faces latérales (29, 42) du corps polyédrique (6) sont agencées pour servir de surfaces d'appui (45, 46) contre une butée de guidage (49) côté établi de meulage.
EP84103750A 1983-10-27 1984-04-05 Dispositif auxiliaire pour l'affûtage de forets hélicoidaux Expired EP0143870B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT84103750T ATE31655T1 (de) 1983-10-27 1984-04-05 Hilfsgeraet zum nachschleifen von spiralbohrern.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19833338910 DE3338910A1 (de) 1983-10-27 1983-10-27 Hilfsgeraet zum nachschleifen von spiralbohrern
DE3338910 1983-10-27

Publications (2)

Publication Number Publication Date
EP0143870A1 EP0143870A1 (fr) 1985-06-12
EP0143870B1 true EP0143870B1 (fr) 1988-01-07

Family

ID=6212809

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84103750A Expired EP0143870B1 (fr) 1983-10-27 1984-04-05 Dispositif auxiliaire pour l'affûtage de forets hélicoidaux

Country Status (5)

Country Link
US (1) US4566227A (fr)
EP (1) EP0143870B1 (fr)
JP (1) JPS6094261A (fr)
AT (1) ATE31655T1 (fr)
DE (2) DE3338910A1 (fr)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4638603A (en) * 1986-01-29 1987-01-27 Hanson Harvey E Device for sharpening single-flute countersinks
US4974372A (en) * 1989-04-12 1990-12-04 Chantalat Vinit P Universal device for sharpening drill bits
US20050053439A1 (en) * 2003-09-09 2005-03-10 Yuhong Wang Two-flute twist drill
EP2321090B1 (fr) * 2008-06-26 2017-12-06 TJ Utveckling AB Dispositif d'affûtage d'une pointe de foret hélicoïdal et son procédé d'utilisation
CN102756307A (zh) * 2012-07-31 2012-10-31 长城汽车股份有限公司 修磨复杂刀具的方法及砂轮
US8439727B1 (en) * 2012-08-06 2013-05-14 Leo F. Woodard Drill bit sharpening tool
CN112893750A (zh) * 2021-01-14 2021-06-04 任洪胜 一种五金件胚料加工自动锻造成型机

Family Cites Families (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US388784A (en) * 1888-08-28 mossbeeg
US201449A (en) * 1878-03-19 Improvement in drill-grinders
GB575664A (en) * 1943-03-01 1946-02-27 Robert Howard Clark Fixture for grinding thread cutting tools
GB563546A (en) * 1943-03-18 1944-08-18 Charles Crofton And Company En Improvements relating to jigs for use in grinding drill bits
US2408544A (en) * 1945-01-01 1946-10-01 Banner Joseph Twist drill sharpener
US2595950A (en) * 1949-05-20 1952-05-06 William C Keebler Tool bit grinding fixture
GB678057A (en) * 1950-06-06 1952-08-27 Leonard Cosens Improvements in or relating to jigs for the grinding of lathe and like cutting tools
US2730849A (en) * 1952-09-20 1956-01-17 James V Novak Drill bit grinding fixtures
US2821820A (en) * 1956-03-05 1958-02-04 Wesley W Thumann Guide for sharpening drill bits
US3121983A (en) * 1959-02-05 1964-02-25 Harvey W English Drill grinding attachment
US3169353A (en) * 1961-11-17 1965-02-16 Lester S Krulwich Drill grinding apparatus
US3373530A (en) * 1965-07-30 1968-03-19 Clyde E. Cooprider Sharpening fixture for twist drills
US3932964A (en) * 1971-12-13 1976-01-20 James B. Simms Multi-angle grinding fixture
DE2445453C2 (de) * 1974-09-24 1985-06-13 Robert Bosch Gmbh, 7000 Stuttgart Bohrerschleifeinrichtung
DE2456173A1 (de) * 1974-11-28 1976-08-12 Wolfcraft Robert Wolff Kg Hilfsvorrichtung fuer ein nachschleifen von bohrern
US3961450A (en) * 1975-02-10 1976-06-08 Kenneth Kay Knaell Twist drill sharpening apparatus
DE2632034C2 (de) * 1976-07-16 1986-07-31 Robert 5446 Engeln Wolff Hilfsvorrichtung zur Erleichterung des Nachschleifens von Spiralbohrern
DE7931294U1 (de) * 1979-11-06 1980-06-26 Hawera Probst Gmbh + Co, 7980 Ravensburg Schleifhilfe
DE3146664C1 (de) * 1981-11-25 1983-07-07 Karl 7539 Kämpfelbach Reiling Haltevorrichtung fuer Bohrer zum Schleifen der Schneiden

Also Published As

Publication number Publication date
EP0143870A1 (fr) 1985-06-12
ATE31655T1 (de) 1988-01-15
DE3468355D1 (en) 1988-02-11
US4566227A (en) 1986-01-28
DE3338910A1 (de) 1985-05-09
JPS6094261A (ja) 1985-05-27

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