EP0346425A1 - Procede de taillage de meules. - Google Patents

Procede de taillage de meules.

Info

Publication number
EP0346425A1
EP0346425A1 EP89900576A EP89900576A EP0346425A1 EP 0346425 A1 EP0346425 A1 EP 0346425A1 EP 89900576 A EP89900576 A EP 89900576A EP 89900576 A EP89900576 A EP 89900576A EP 0346425 A1 EP0346425 A1 EP 0346425A1
Authority
EP
European Patent Office
Prior art keywords
grinding wheel
workpiece
dressing
grinding
cutting surface
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
EP89900576A
Other languages
German (de)
English (en)
Other versions
EP0346425B1 (fr
Inventor
Horst Josef Wedeniwski
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.)
Fortuna Werke Maschinenfabrik GmbH
Original Assignee
Fortuna Werke Maschinenfabrik GmbH
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 Fortuna Werke Maschinenfabrik GmbH filed Critical Fortuna Werke Maschinenfabrik GmbH
Publication of EP0346425A1 publication Critical patent/EP0346425A1/fr
Application granted granted Critical
Publication of EP0346425B1 publication Critical patent/EP0346425B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

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
    • B24B53/00—Devices or means for dressing or conditioning abrasive surfaces
    • B24B53/06—Devices or means for dressing or conditioning abrasive surfaces of profiled abrasive wheels
    • B24B53/08—Devices or means for dressing or conditioning abrasive surfaces of profiled abrasive wheels controlled by information means, e.g. patterns, templets, punched tapes or the like
    • 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
    • B24B49/00—Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation
    • B24B49/18—Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation taking regard of the presence of dressing tools

Definitions

  • the invention relates to a method for dressing a grinding wheel, in which a dressing roller is moved along a raw surface of the grinding wheel by means of a numerically controlled multi-coordinate movement unit to produce a predetermined circumferential profile of the grinding wheel.
  • a dressing roller is moved along a raw surface of the grinding wheel by means of a numerically controlled multi-coordinate movement unit to produce a predetermined circumferential profile of the grinding wheel.
  • an annular groove of a given width and with a given fillet in the transition from the cylindrical base surface to the radial side surfaces can be ground in a single operation by providing the outer surface of the grinding wheel with a peripheral profile that precisely matches the dimensions of the contour of the Ring groove corresponds.
  • various external cylindrical grinding processes in which, for example, bushes, flanges and the like are ground with almost any rotationally symmetrical contours
  • the numerically controlled multi-coordinate movement unit of the dressing roller is given a data record which corresponds to the spatial coordinates of the workpiece profile to be ground.
  • the dressing roller is then guided over the circumferential surface of the grinding wheel in such a way that the desired circumferential profile is created.
  • process parameters in the control in the numerical control of a grinding machine, ie when setting the movement sequence between the workpiece and the grinding wheel, in order to optimize the grinding process in this way.
  • the invention is based on the object of developing a method of the type mentioned in such a way that specifications of a grinding process can already be taken into account when dressing the grinding wheel and not only during grinding, so that as a result the overall control of the grinding machine, in particular the movement sequence during the grinding process, remains unaffected.
  • This object is achieved according to the invention in that, depending on process parameters of a grinding process to be carried out on a workpiece by means of the grinding wheel after dressing, a peripheral profile is determined and this is then generated on the grinding wheel by means of the dressing roller.
  • the object on which the invention is based is completely achieved in this way, because for the first time a dressing strategy is used in which not only the workpiece geometry but also process parameters, ie path speeds, feed speeds, material properties, surface qualities and the like are included in the shaping of the grinding wheel.
  • a method for dressing a grinding wheel for a subsequent high-speed peeling process is used a main cutting surface of the grinding wheel with a high axial feed speed creates a helicoidal transition between the raw and finished dimensions and a secondary cutting surface rests on the finished dimension of the workpiece.
  • the axial position of the secondary cutting surface is set as a function of the process parameters.
  • This measure has the advantage that the shape of the grinding wheel can be optimized for this special application in such a way that a grinding process is set for a predetermined surface quality, which produces the desired surface quality with a minimum machining time.
  • the method according to the invention can be used with different types of grinding wheels, in which either the grinding wheel axis is inclined to the axis of the workpiece or parallel to it.
  • the main cutting surface is produced in such a way that it lies against the helicoidal transition along a radial line.
  • This measure has the advantage that essentially axial forces are exerted on the workpiece, so that both the heat development and the deflection of the workpiece due to radial loading are minimized.
  • the method according to the invention can, however, also be used advantageously in circumstances in which the main cutting surface is produced in such a way that it lies against the helicoidal transition along a direction inclined to a radial direction.
  • the inclination angle of the main cutting surface provides another freely selectable parameter in order to optimize the grinding process.
  • FIG. 3 shows a representation similar to FIG. 2, but for a modification of the method according to the invention
  • FIG. 4 shows a further illustration similar to FIG. 2, but for yet another variant of the method according to the invention.
  • 10 designates a grinding machine of the usual type, in which a grinding spindle 11 rotates a grinding wheel 12 about a grinding wheel axis 13 at a speed n s . Taking into account a grinding wheel diameter d s, this results in a path speed v s on the outer circumference of the grinding wheel 12.
  • the grinding wheel axis 13 is inclined at an angle 14 to a workpiece axis 15, as is known per se.
  • a workpiece 20 is clamped between a conventional chuck 21 of a workpiece spindle and a center point 22.
  • the workpiece 20 can be displaced along its axis by means of a drive (not shown in FIG. 1) at an axial feed speed v z . It goes without saying that, alternatively, the workpiece 20 can also stand still and the grinding wheel 12 can be displaced in the direction of the workpiece axis 15 if this is more favorable in individual cases.
  • the workpiece 20 is rotated by the chuck 21 at a speed nw, which leads to a path speed v * at the periphery of the workpiece 20 with a workpiece diameter dw.
  • M in FIG. 1 denotes the material properties of the workpiece 20, in particular its modulus of elasticity, Toughness etc., while 0 is intended to symbolize a desired surface quality on the machined workpiece 20.
  • the grinding wheel 12 is initially provided with raw, conical surfaces 30 and 31, of which surface lines each run parallel or perpendicular to the surface of the workpiece 20 to be machined.
  • a dressing roller 40 is provided.
  • the dressing roller 40 is preferably of a double-conical shape with two conical surfaces 41, 42 which intersect at an acute angle along a circumferential line 43.
  • the dressing roller 40 is set with diamonds 44.
  • a shaft 45 of the dressing roller 40 is connected to a drive connection 46, which leads to a three-coordinate drive 47.
  • the drive 47 is designed so that it can not only set the speed n of the dressing roller 40 but also its position in space according to three spatial coordinates.
  • the drive 47 can move the dressing roller 40 vertically via the connection 46 in FIG. 1, as indicated by an arrow 48.
  • the dressing roller 40 can dress the raw surface 30 of the grinding wheel 12.
  • the drive 47 can also rotate the dressing roller 40 via the drive connection 46, for example, by 90 ° and move in a direction parallel to the workpiece axis 15, as indicated by an arrow 49 in FIG. 1. With such a The second raw surface 31 of the grinding wheel 12 can then be machined.
  • any inclined or curved movement paths can also be carried out, as is known per se from multi-coordinate drives.
  • a control device 55 which has a large number of inputs 56 and an output 57 which is connected to the drive 47.
  • Signals are present at the inputs 56, which were detected as state parameters, for example by manual digital preselection or also by sensors.
  • control device 55 determines a circumferential profile for the grinding wheel 12, which is then subsequently generated on the grinding wheel 12 by actuating the drive 47 by means of the dressing roller 40.
  • Fig. 2 shows a first application example of such a dressing process.
  • the workpiece 20 has already been partially machined in the illustration in FIG. 2, and in the left half of FIG. 2 a raw dimension of the still unprocessed workpiece 20 can be seen at 60, while a finished dimension is symbolized in the right half of FIG. 2 at 61 .
  • the grinding wheel 12 is provided with three conical surfaces 62, 63, 64.
  • the first conical surface 62 serves as the main cutting edge
  • the second conical surface 63 as the secondary cutting edge
  • the third conical surface 64 as the non-engaging rear surface of the grinding wheel 12.
  • the action of the main cutting surface 62 creates a helicoidal transition 66 between the raw dimensions 60 and Finished dimension 61.
  • the secondary cutting surface 63 lies on the finished dimension 61 of the workpiece 20 over an axial length 1N.
  • the main cutting edge angle is set at 90 °, so that the main cutting surface 62 bears against the helical transition 66 along a radial line.
  • the third conical surface 64 includes a clearance angle with the finished dimension 61 of the workpiece 20.
  • the dressing strategy explained above now proceeds from the process parameters mentioned, preferably the length 1N of the secondary cutting surface 63 and, if appropriate, additionally the angles and determined so that the dressing roller 40 can then produce the resulting circumferential profile on the grinding wheel 12.
  • the machining process shown schematically in FIG. 2 can preferably run with the following parameters:
  • a diamond form roller with the designation SG71P-200-1.7 is used as the dressing tool.
  • the roll has a diameter DR of 200 mm.
  • the grain size of the diamonds is 200 ⁇ m.
  • the grain distribution is statistically scattered.
  • the packing density is 50 ⁇ / cm 3 in the positive method.
  • the bond is galvanic and the covering thickness is 0.85 x2, the covering height being 10 mm.
  • a CBN grinding wheel with the type designation B 151MSS387V420 is used as the grinding tool.
  • the grinding wheel diameter Ds is 600 mm.
  • the grain size d k of the CBN grains is 151 ⁇ m.
  • the base of the grinding wheel is made of steel and the edge radius r is 2 mm.
  • a grinding wheel peripheral speed vs of 140 m / s, a workpiece diameter dw of 30 mm, an oversize a of 1 mm, a machining length L of 120 mm, a surface quality R a of 0.8 ⁇ m are specified and the material of the workpiece is specified normally machinable with a characteristic value q of 70.
  • the characteristic value q denotes the speed ratio of the grinding wheel and workpiece. This characteristic value is determined according to the machinability of the workpiece material.
  • the machinability of metallic materials is significantly influenced by their chemical composition and structure. The microstructure in turn depends on the production of the material (casting, hot or cold forming) and on the post-treatments used (hardening, annealing).
  • the materials with a high alloy content, the additional carbides contain, due to different deformability different chip types, which determine the behavior of machinability.
  • Short-chipping or long-chipping materials can be meaningfully assigned according to the speed ratio if you consider machinability based on hardness and toughness. If you compare the machinability of the different materials according to this criterion, the greater the speed ratio, the greater the carbide content (cementite) and the more or less homogeneous fine structure (martensite).
  • the geometry of the grinding wheel is defined by the dressing process according to the invention in that a length IN of the minor cutting edge is set. In the present example, this is done according to the relationship:
  • q is the ratio of the peripheral speeds of the grinding wheel and the workpiece.
  • q 70.
  • U is the so-called degree of overlap in the above-mentioned relationship, which results because the minor cutting edge of length 1N each detects areas during rotation of the workpiece and axial infeed which were also already partially grasped by the grinding wheel during the previous rotation of the workpiece were.
  • the relationship applies to the degree of coverage U:
  • a degree of coverage U 3.125 is then calculated from the variables mentioned above.
  • Vfa is the axial feed speed for which the relationship: applies.
  • the reason for that is the clearance angle to set as small as follows:
  • the grinding wheel is not only delivered once before it is used, but it must also be used later during the Use, as is generally customary, to be dressed so that the grinding properties of the grinding wheel are retained or restored even after prolonged use.
  • the length 1N of the minor cutting edge increases because the further section at the rear of the minor cutting edge under the clearance angle connects.
  • the main cutting edge must also be dressed in order to shorten the axial length 1N of the minor cutting edge again. It can now be shown that with the same large infeed of the dressing tool on the main cutting edge and on the auxiliary cutting edge, as is desired for technological reasons anyway, the length 1N of the auxiliary cutting edge remains unchanged when the clearance angle is set as small as possible, for example in the range 1 ° to 3 °.
  • the grinding wheel peripheral speed vsd is expediently about 30 m / s.
  • the ratio of the peripheral speeds of the grinding wheel and the dressing roller q D is, for example, set to the value 0.8. These values result in a surface structure of the grinding wheel which corresponds precisely to the desired effective roughness depth Rt of 6.4 ⁇ m.
  • the grinding wheel peripheral speed vsd and the peripheral speed ratio q D are used to calculate a grinding wheel speed ns of 955.42 min -1 .
  • the peripheral speed of the dressing roller VR is calculated in a corresponding manner at 24 m / s.
  • the speed of the dressing roller is then calculated with a roller diameter DR of 200 mm at 2293 min -1 .
  • the values for the axial and radial infeed result from the grain size d K , which in the present case can be 0.2 mm, multiplied by a constant factor.
  • the axial infeed S D then results with a factor of 0.4 to 0.08 and the radial infeed a D in a corresponding manner to 0.005.
  • the infeed speed of the dressing roller V fd is then calculated to be 76.43 mm / min from the axial infeed per revolution of the grinding wheel and the grinding wheel speed ns.
  • the grinding machine with the control device 55 controls the dressing roller 40, for example, from a position in FIG. 1 to the right of the grinding wheel 12 to a point which is an extension of the third conical surface 64 of the grinding wheel 12. In this position, the grinding wheel 12 and the dressing roller 40 are set in rotation and at the same time a coolant is supplied. From the first point in the extension of the third conical surface 64, the dressing roller 40 is now guided in an XZ control along the third conical surface 64 until a point at the transition from the third conical surface 64 to the second conical surface 63, ie the minor cutting edge, is reached. The grinding wheel is now guided along the minor cutting edge over the length IN, specifically in the Z direction, as indicated by the arrow 49 in FIG. 1. After passing through the length 1N, the control is switched over again, so that the dressing roller 40 is moved along the main cutting edge 30 in the X direction, ie in the direction of the arrow 48 in FIG. 1.
  • the control unit 55 now moves the dressing roller 40 back to the starting point in rapid traverse.
  • the grinding wheel 12 conditioned in this way is now used for high-speed peripheral grinding, a value of 981.05 mm 3 / mm s resulting from the known relationships for the related chip removal volume Q'w, the peripheral speed vw of the workpiece being 2 m / s and consequently the speed nw of the workpiece at 1273.88 U / min. lies.
  • the main cutting edge angle is no longer 90 ° but, for example, 45 °, so that the helicoid transition 66 'is formed as a helically conical conical surface.
  • a third parameter besides 1N and to create optimal process conditions is free choice.
  • FIG. 4 shows yet another variant, which differs from those described so far in that the grinding wheel axis runs parallel to the workpiece axis.
  • the secondary cutting surface 63 ′′ is a circular cylindrical peripheral surface.
  • the main cutting surface 62 ′′ can, as shown in FIG. 4, be a conical surface so that a main cutting angle arises that is smaller than 90 °.
  • the main cutting surface in this exemplary embodiment can be a radial, ie flat surface, so that a main cutting edge angle of 90 ° would also be established here.
  • the method according to the invention is in principle independent of the type of grinding wheel used.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Grinding Of Cylindrical And Plane Surfaces (AREA)

Abstract

Selon un procédé de taillage de meules (12), un rouleau de taillage (40) est déplacé le long d'une surface brute (30, 31) de la meule par une unité de déplacement (46, 47) à coordonnées multiples et à commande numérique, produisant ainsi un profil prédéterminé sur la circonférence de la meule. Afin de simplifier la commande du processus de taillage et notamment d'optimiser par rapport au temps un procédé de rectification à écroûter à haute vitesse produisant de grands volumes de copeaux en peu de temps, on détermine premièrement un profil circonférentiel en fonction des paramètres du procédé de rectification d'une pièce à usiner (20) à effectuer par la meule (12) après son taillage, puis on taille ce profil sur la circonférence de la meule (12) au moyen du rouleau de taillage (40).
EP89900576A 1987-12-23 1988-12-21 Procede de taillage de meules Expired - Lifetime EP0346425B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE3743811 1987-12-23
DE3743811 1987-12-23
PCT/DE1988/000775 WO1989005711A1 (fr) 1987-12-23 1988-12-21 Procede de taillage de meules

Publications (2)

Publication Number Publication Date
EP0346425A1 true EP0346425A1 (fr) 1989-12-20
EP0346425B1 EP0346425B1 (fr) 1994-05-18

Family

ID=6343435

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89900576A Expired - Lifetime EP0346425B1 (fr) 1987-12-23 1988-12-21 Procede de taillage de meules

Country Status (3)

Country Link
EP (1) EP0346425B1 (fr)
DE (1) DE3889655D1 (fr)
WO (1) WO1989005711A1 (fr)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH682380A5 (de) * 1990-07-25 1993-09-15 Agathon Ag Maschf Verfahren und Vorrichtung zum Aussenrundschleifen eines zylindrischen Werkstückes.
FR2691663B1 (fr) * 1992-05-26 1996-10-11 Essilor Int Procede de ravivage de meules, disque et machine pour sa mise en óoeuvre.
DE19717795A1 (de) * 1997-04-26 1998-10-29 Zahnradfabrik Friedrichshafen Verfahren zum Abrichten von Profilschleifscheiben
JP6252270B2 (ja) * 2014-03-17 2017-12-27 株式会社ジェイテクト 研削盤の砥石のツルーイング方法及び研削盤
CN113139245A (zh) * 2021-04-02 2021-07-20 大连理工大学 一种用于cfrp磨削的砂轮设计方法

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB986427A (en) * 1961-07-13 1965-03-17 Eugene Fouquet High-performance grinding process, more particularly for the machining of metals of all degrees of hardness
US3973433A (en) * 1972-06-15 1976-08-10 Finike Italiana Marposs-Soc. In Accomandita Semplice Di Mario Possati & C. Method and relative apparatus for controlling the cutting capacity of the grinding wheel of a grinder
US4103668A (en) * 1976-07-30 1978-08-01 Toyoda-Koki Kabushiki-Kaisha Dressing apparatus for grinding wheel
US4570389A (en) * 1984-01-30 1986-02-18 The Warner & Swasey Company Method of adaptive grinding
EP0161674B1 (fr) * 1984-05-16 1991-02-20 Toyoda Koki Kabushiki Kaisha Commande numérique d'une machine à meulage
US4603677A (en) * 1984-08-29 1986-08-05 Gile Richard H Orthogonal dressing of grinding wheels
EP0176654B1 (fr) * 1984-09-26 1992-07-15 Erwin Junker Procédé et dispositif pour rectifier à grande vitesse des profils de pièces à symétrie de révolution
US4631870A (en) * 1985-03-28 1986-12-30 Industrial Technology Research Institute CNC grinding machine
DE3529427A1 (de) * 1985-08-16 1987-02-26 Fortuna Werke Maschf Ag Verfahren und vorrichtung zum einleiten eines abrichtvorganges einer schleifscheibe in abhaengigkeit von deren stumpfungsgrad

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8905711A1 *

Also Published As

Publication number Publication date
DE3889655D1 (de) 1994-06-23
EP0346425B1 (fr) 1994-05-18
WO1989005711A1 (fr) 1989-06-29

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