EP1144138B1 - Method for grinding at least one surface on a cutting knife used in machining, use of said method and grinding wheel used to carry out said method - Google Patents

Description

The invention relates to a method for grinding at least a surface on one used in cutting technology Cutting knife with a grinding wheel rotating about an axis, whose working area is an annular surface, an advantageous one Use of the process and a grinding wheel for Execution of the procedure.

When grinding used in cutting technology Cutting knives exist today two technologies, namely Shape grinding and generation grinding. The main difference between these two grinding technologies is that in form grinding, the generators in advance on the Tool is generated (dressing). In this way it is created a simple process in which the grinding tool of the profile carrier is. There is then only one feed movement for surface creation necessary. In contrast, the generation loop the generator by at least two machine movements generated, which makes the process complex. The generation grinding but is more flexible than shape grinding because a variety of different combinations of movements Lets create profiles. The increase in flexibility becomes extraordinary appreciated if special profiles in a small or have to be produced in a medium lot size. The Bringing the generation profile to the grinding wheel is in this Case not required. The generation grinding is however associated with greater control effort than profile grinding.

A method of the type mentioned at the outset is known from US Pat. No. 5,168 661 A known. In this known method, a special one Grinding wheel configuration and a special movement when moving the cutting knife relative to the Grinding wheel used to form a number of enable desired surfaces on a cutting knife. They are also said to have spiral grooves on the workpiece surface by the highest of the grinding wheel protruding grain are generated, avoided. To this The purpose of the known method is a profile grinding wheel used in the aforementioned US 5 168 661 A also described and illustrated, however, in US 5 241 794 is claimed. This well-known profile grinding wheel has a grinding profile for finishing grinding a narrow, essentially the outer part of the disk surface has a flat surface which becomes a surface of a Workpiece during the finishing grinding essentially is held tangential. This profile grinding wheel is made from an expensive, extremely durable abrasive material such as CBN crystals, but other materials such as Aluminum oxide can be used as the profile grinding wheel does not need to be dressed. Except the narrow flat Surface used for finishing grinding has the working area of the known profile grinding wheel inner conical surface, an inner arcuate surface and an outer arcuate surface. For rough grinding become the inner conical surface, the inner arcuate Surface and / or the outer arcuate surface used. The roughed knife surface is then with the narrow flat surface.

This known method requires a complicated sequence of movements, because each one has to be sharpened on a cutting knife Surface at least with the inner conical surface roughed and then with the narrow flat surface is arbitrated. The used in the known method Profile grinding wheel consists in its roughing and Finishing area made of abrasive materials with different Grain size. The to be carried out by the known profile grinding wheel Roughing and finishing work is therefore carried out in two different ways Grinding wheel areas distributed, one of which only for rough grinding and the other only for finish grinding is used. With the cutting knives, which by the known method are ground, it is the usual high-speed steel knives. The disadvantage of the known Process further that finishing grinding from concave curved surfaces is not possible because the finishing always done with the narrow flat surface. Furthermore, at the known generation grinding process disadvantageous that due to the CBN-discs carbide knives used do not let it grind. A CBN disc would not be sufficient Stability when machining hard metal knives. Tungsten carbide knives are also not easy to do Form grinding. For carbide knives would be for shape grinding a wide diamond wheel is required, these diamond wheels it is very difficult to condition.

For example, it can be used to manufacture the gears of a transmission six different knife types are required to create six different profiles. These six profiles could be on a Borazon grinding wheel be produced by re-profiling. On a diamond grinding wheel wouldn't that be economical. Rather, they should several different diamond discs for shape grinding to be provided.

The object of the invention is a method of the aforementioned Way of specifying a simpler workflow and the use of a grinding wheel with a simpler configuration enables and in particular also the grinding of curved Areas allowed. In addition, an advantageous use of the process and a grinding wheel to carry out the Procedure are specified.

This object is achieved by the method according to claim 1, through the use according to claim 15 or solved by the grinding wheel according to claim 16.

In contrast to the known method with a complicated configuration The grinding wheel can be used in the process according to the Invention use a universal grinding wheel, the work area is an annular surface that is arcuate in axial section Profile. By the method according to the invention first grinds a surface on the cutting knife with the ring surface under a first spatial orientation between grinding wheel and cutting knife by at least one first translational relative movement between grinding wheel and cutting knife, and then at least part the area created with the ring area under a second spatial orientation between grinding wheel and cutting knife by at least one second translational relative movement ground between grinding wheel and cutting knife. According to the invention, this can be done with an area of the ring surface grind a surface and then this surface with a smooth the other area of the ring surface. For that she needs grinding wheel used in the method according to the invention no different specifications in these two areas to have, because just by choosing the right parameters, coupled with the two different spatial Orientations, the same area of the cutting knife can be sand and then sand, e.g. schruppund finishing grinding, regardless of whether the finished Surface is flat, convex or concave. The one in the process used according to the invention grinding wheel needs in their Working area to have only a radius and therefore points a much simpler configuration than that of the known method used grinding wheel. The procedure is also in the inventive method much easier than in the known method, because only two different spatial orientations selected can be, for example, for the cutting knife in a different angle is selected with respect to the grinding wheel. The method according to the invention is therefore essential in use more flexible than the known method. The spiral Grooves by the known method in a complex manner can also be avoided by the method according to the invention avoided without the need for a grinding wheel with a narrow, flat surface for finishing grinding use.

When using the method according to claim 15, the generation grinding of carbide knives possible. That is a very significant use of the method according to the invention, because in the manufacture of gears more and more that Dry milling is used in the cutting knife made of hard metal must be used. Carbide can only be used with Machining diamond, but diamond profile grinding wheels are hardly profilable by dressing, so that the profile grinding of carbide knives practically eliminated. The procedure after The invention can therefore not only be used for generating grinding of high-speed steel cutting knives, but also of cutting blades made of hard metal, simply by a Diamond grinding wheel is used.

To carry out the method according to the invention, a Grinding wheel used according to the preamble of claim 16, whose working area is the same as that of US 5 259 148 A known grinding wheel is formed, but which is for generating grinding of glass lenses is provided. The stake such a diamond cup grinding wheel with a work area, partly in a forehead area and partly in one Cylinder area of the cup grinding wheel has the advantage that on a cutting knife used in cutting technology optionally flat or curved surfaces (with the forehead area) or concave surfaces (with the cylinder area or the Forehead area) can be ground, depending on the spatial Orientation between grinding wheel and cutting knife. With a Diamond grinding wheels improve wear behavior and the wheel geometry is more stable than with the known CBN profile grinding wheel. The diameter of the so-called profiling Point that can be determined exactly changes during one technological phase compared to the CBN profile grinding wheel no more. A position compensation the diamond grinding wheel is therefore not necessary. About that can also be a knife shoulder, where the measurement is bigger, in a separate technological phase, which contributes to increasing the economics of the process.

Since the working area in the grinding wheel according to the invention is an annular surface, which is an arcuate in axial section Profile that extends over a total contact angle, can be selected within this work area by choosing different profile tilt angles for the roughing and finishing work areas the grinding wheel against each other or even separate. Because of the total contact angle of about 145 ° can be used in the part of the work area Select the front area and / or cylinder area of the grinding wheel. Because of that provided in the grinding wheel according to the invention circular arc shaped profile that has a radius of curvature has that in a range from 0.5 to 5 mm and preferably from 0.5 to 1 mm, and most preferably 0.5 mm or less is, there are flexible options for editing the Cutting blade.

Using the method according to the invention Grinding cutting knives can be made from different types of carbide consist.

A knife flank generated with the grinding wheel according to the invention can consist of one or more geometric surfaces. The surface and flank shape is determined by the relative Positioning of grinding wheel and cutting knife generated. In the cylinder area of the grinding wheel creates this sense a concave surface, whereas the forehead area is a curved one or can create a flat surface. Therefore, the knife edge from two or more than two different surfaces consist (e.g. of a concave surface with a larger one Clearance angle and from a flat facet with a smaller one Clearance angle).

The objects form advantageous embodiments of the invention of subclaims.

If in an advantageous embodiment of the method according to the invention the first spatial orientation between the grinding wheel and cutting knife by setting a first position of the cutting knife in relation to the grinding wheel and the second spatial orientation between the grinding wheel and cutting knife by setting a second position of the cutting knife in relation to the grinding wheel a conventional grinding machine can be used, where the grinding wheel rotates around its own axis and in the Y axis can be moved vertically.

If in a further advantageous embodiment of the method According to the invention, the first position of the cutting knife is chosen that the grinding wheel is the surface on the cutting knife with one in a cylinder area of the grinding wheel located first surface element of the ring surface, and the second position of the cutting knife is chosen so that the Grinding wheel the at least part of the generated area on the cutting knife with one in a forehead area of the Grinding surface located second surface element of the ring surface can then be created with the cylinder area concave surface optionally ground with the forehead area the surface created remains concave or becomes flat or at least partially flat.

If in a further advantageous embodiment of the invention second position of the cutting knife is chosen so that the Grinding wheel the at least part of the generated area produced on the cutting knife as a concave or flat facet, only needs the spatial orientation between the grinding wheel and cutting knife to be chosen accordingly.

If in a further advantageous embodiment of the method according to the invention in the creation of a surface on the Cutting the cut only by infeed in a Y-axis If the machine is carried out, the generation grinding process can be carried out in a simple manner Control wise.

If in a further advantageous embodiment of the method according to the invention, the generation of the surface on the cutting knife only with three mutually perpendicular linear axes and other axes are used as mere adjustment axes and before actually generating the surface on the Cutting knives can be positioned, controlled by three Linear movements any desired surface on the cutting knife on a conventional grinding machine like one Grinding machine of type B22 from the applicant (cf. company brochure "CNC tool grinding cell Oerlikon B22", OGT-B22 / D / hJ) or type B5 of the applicant (see the two company prospectuses each with the designation "profil B 5", K 1.11 - d / e - cH or OGT profile B5 / E / dH).

If in a further advantageous embodiment of the method according to the invention, the area on the cutting knife in one and / or or in the other step in two passes two first and second translatory relative movements between Grinding wheel and cutting knife is generated can Rough and finish grinding the surface in two steps.

If in a further advantageous embodiment of the method According to the invention this was carried out on a CNC machine the grinding process with regard to geometry and Control technology in the usual way.

If in a further advantageous embodiment of the method according to the invention for determining interrelationships between geometrical and technological parameters for generation grinding a CDS computing system (CDS is the abbreviation for Controlled Disk System) is only one special program package required to use a conventional grinding machine, for example the above Type B22, on the invention To convert generation loops.

If in a further advantageous embodiment of the method according to the invention, the area on the cutting knife in one Step is generated with at least one roughing cut and the at least part of the area created in the other You can grind the step with a finishing cut Create each surface separately and the surface macro - separately influence the micro-geometry of the surface.

If in a further advantageous embodiment of the method according to the invention the translational relative movement between Grinding wheel and cutting knife is produced in that the Cutting knife relative to the grinding wheel an impact or Pulling movement is given, the desired simple Workflow by choosing this movement accordingly achieve.

If in a further advantageous embodiment of the method according to the invention when grinding with a finishing cut the cutting knife relative to the grinding wheel Pulling movement is the preferred workflow, depending on the surface to be ground instead of Pulling movement but a pushing movement for the finishing cut be beneficial. Every technological phase (roughing or Finishing) can be in the advantageous embodiments of the method geometrically and technologically separate according to the invention To be defined.

If in a further advantageous embodiment of the method According to the invention, a grinding wheel is used, which in their entire ring surface used for grinding the same Specifications, the selection is advantageously made of roughing and finishing cuts simply by selecting of feed parameters such as feed direction and - speed.

In a further advantageous embodiment of the method according to the Invention are roughing and finishing in the two steps of the method according to the invention and thus for grinding used surface elements of the ring surface against each other interchangeable. Two technological phases, roughing and Finishing may be necessary, technological However, the process can have multiple roughing cuts and one finishing cut include, and vice versa.

If in an advantageous embodiment of the grinding wheel according to the invention it has a fixed geometry and not is dressable, their manufacture is particularly simple. It is much easier, only with a certain radius grind if the radius is kept constant, which at Diamond grinding wheels is the case that has a long service life to have. One can assume that the procedure with constant radius is what the control of the process simplified and facilitated. The question of whether a dressable or a non-dressable grinding wheel depends on the grinding ability of the grinding wheel from.

A non-dressable grinding wheel preferably consists of a metallic carrier body on which an abrasive coating is made Diamond grains and a galvanic bond from which the Protruding diamond grains is applied, the galvanic Binding consists of nickel.

Instead of a non-dressable grinding wheel, one can dressable grinding wheel can be used. That is because the construction of the B22 machine without further ado possible because the machine has a suitable dressing device has and suitable dressing software is provided, in order to be able to dress the grinding wheel from time to time to profile their radius again.

Fig. 1

eine herkömmliche Schleifmaschine des Typs B22 der Anmelderin, die durch Weiterentwicklung ihrer Software zur Ausführung des erfindungsgemäßen Verfahrens hergerichtet ist,

Fig. 2

eine schematische Darstellung einer Topfschleifscheibe für das erfindungsgemäße Verfahren,

Fig. 3

eine Erläuterungsdarstellung der Schleifscheibe nach der Erfindung,

Fig. 4

als vergrößerte Einzelheit den Arbeitsbereich der Schleifscheibe nach der Erfindung,

Fig. 5a-5c

drei verschiedene Messertypen, die durch das Verfahren nach der Erfindung auf einer Maschine nach Fig. 1 schleifbar sind, wobei jeweils links die Anordnung des Schneidmessers in einem Messerkopf und rechts die Anordnung des Schneidmessers in der Spannvorrichtung der Schleifmaschine dargestellt ist,

Fig. 6a

die Schnittaufteilung an einem Schneidmesser bei unterschiedlichem Abtrag an Messerschulter und -spitze,

Fig. 6b

die Schnittaufteilung an einem Schneidmesser bei etwa konstantem Abtrag an Messerschulter und -spitze,

Fig. 7

den Einsatz des Verfahrens nach der Erfindung zum Schruppen der Fläche eines Schneidmessers in zwei Durchgängen,

Fig. 8

den Einsatz des Verfahrens nach der Erfindung zum Schlichten der gleichen Fläche wie in Fig. 7,

Fig. 9

das Schleifen einer Schulter an einem Schneidmesser mit der Schleifscheibe nach der Erfindung auf der softwaremäßig weiterentwickelten Schleifmaschine des Typs B22,

Fig. 10

die verschiedenen möglichen Schleifpositionen für verschiedene technologische Phasen für das Schleifen eines Schneidmessers mit der Schleifscheibe nach der Erfindung,

Fig. 11

das Schruppen einer Freifläche an dem Schneidmesser mit der Schleifscheibe nach der Erfindung,

Fig. 12

das Schlichten derselben Freifläche wie in Fig. 11 mit der Schleifscheibe nach der Erfindung,

Fig. 13

die Ermittlung des Arbeitsbereiches der Schleifscheibe beim Schruppen,

Fig. 14

eine Darstellung zur Erläuterung, wie sich durch Änderung eines Profilkippwinkels PKW ein Gesamtkontaktwinkel GKW verschiebt,

Fig. 15

die Ermittlung des Arbeitsbereiches der Schleifscheibe nach der Erfindung beim Schlichten,

Fig. 16a

das Konditionieren einer abrichtbaren Schleifscheibe mit einer Konturrolle beim Anfahren an die Schleifscheibenkontur, und

Fig. 16b

das Konditionieren einer Schleifscheibe nach der Erfindung mit einer Abrichtrolle durch Interpolation um die Schleifscheibenkontur.

Embodiments of the invention are described below with reference to the drawings. Show it

Fig. 1

a conventional grinding machine of type B22 from the applicant, which is prepared for the execution of the method according to the invention by further development of its software,

Fig. 2

1 shows a schematic illustration of a cup grinding wheel for the method according to the invention,

Fig. 3

an explanatory view of the grinding wheel according to the invention,

Fig. 4

as an enlarged detail the working area of the grinding wheel according to the invention,

5a-5c

three different types of knives which can be ground on a machine according to FIG. 1 by the method according to the invention, the arrangement of the cutting knife in a knife head on the left and the arrangement of the cutting knife in the clamping device of the grinding machine on the right,

Fig. 6a

the division of cuts on a cutting knife with different removal on knife shoulder and tip,

Fig. 6b

the division of cuts on a cutting knife with approximately constant removal of knife shoulder and tip,

Fig. 7

the use of the method according to the invention for roughing the surface of a cutting knife in two passes,

Fig. 8

the use of the method according to the invention for finishing the same area as in FIG. 7,

Fig. 9

grinding a shoulder on a cutting knife with the grinding wheel according to the invention on the software-developed grinding machine of type B22,

Fig. 10

the different possible grinding positions for different technological phases for grinding a cutting knife with the grinding wheel according to the invention,

Fig. 11

the roughing of a free area on the cutting knife with the grinding wheel according to the invention,

Fig. 12

finishing the same free area as in FIG. 11 with the grinding wheel according to the invention,

Fig. 13

determining the working area of the grinding wheel during roughing,

Fig. 14

1 shows an explanation of how a total contact angle GKW is shifted by changing a profile tilt angle PKW,

Fig. 15

the determination of the working area of the grinding wheel according to the invention during finishing,

Fig. 16a

conditioning a dressable grinding wheel with a contour roller when approaching the grinding wheel contour, and

Fig. 16b

conditioning a grinding wheel according to the invention with a dressing roller by interpolation around the grinding wheel contour.

Fig. 1 shows an overall designated by the reference number B22 Knife grinding machine of the applicant's type B20, which actually for grinding bar knives with profile disks using the form grinding method an extension is planned has for grinding cutting knives, in particular Carbide knives, in the production process. The extension exists especially from an expansion of the software for the Control of the knife grinding machine 20, in particular in the area the adjustment control (PMC), the machining cycles and macros of the CNC, the user interface and data management with an integrated PC. The CNC has the function of the "master" and serves for axis control, for executing the part programs (Process flow control), part program management and for CNC screen displays. The adaptation control also called PLC takes over the interface function between the CNC and the knife grinding machine, the control of machine processes, monitoring functions, Machine control panels, digital input / output and interface to the robot / magazine. Because of the available resources (RAM in the PC) is used for each of the two Grinding process (form and production grinding) a program created for the user interface. The switch between the User interface for form or production grinding can during the startup phase of the PC software. The knife shape is only generated with the linear axes X, Y, Z. An A and a C axis are pure adjustment axes and are created before the actual generation grinding Knife surfaces positioned. The path calculation and the Cuts are divided in the PC, so only on the CNC level macros and cycles for workpiece change and conditioning the grinding wheel must be present. The Main interpolation plane for grinding the cutting knives is formed by the axes Y and Z.

The workpiece range includes cutting knives 22, of which in the 5a-5c three different types are shown. The constructive geometry and the arrangement in a cutter head 24 is different for the three types of knives, and therefore the three knife types come in three different Clamping devices 26 ground, Fig. 5a shows one on the left Clearance angle of 8 ° and a knife inclination angle in the Cutter head of 20 °. Accordingly, the cutting knife 22 in Fig. 5a right in the jig 26 an angle of inclination of 28 ° so that the head of the knife can be sharpened without Clearance is arranged. The same applies to the Representations in FIGS. 5b and 5c. The in Figs. 5a and 5c The angles on the far left and top left are for the Description of no interest here and therefore do not need to be explained in more detail. When creating the surface on the Cutting knife 22 is removed only by delivery in the Y axis of the machine, which is indicated in FIGS. 1 and 5a.

An important prerequisite for what is described here Process developed especially for carbide grinding the properties of the A axis are those in FIG. 1 Knife grinding machine 20 shown. In the conventional Shape grinding is only used for the A axis Device positioning and is then clamped. The Head radius is determined by at least two translational movements (Y, Z). These translational movements are below described in more detail with reference to FIGS. 7-15.

The generation grinding process described here is carried out with a Grinding wheel 28 executed, which is preferably a Diamond cup grinding wheel deals. The grinding wheel 28 is schematically in axial section in Fig. 2 and in enlarged Partial representation in the working position shown in Fig. 3. The Grinding wheel 28 consists in that shown in FIG. 3 and Embodiment described here consisting of a carrier body 30 made of steel, on which a grinding surface 32 made of grain and galvanic Binding is applied. The galvanic bond exists made of nickel, which is electrolytically applied to the Support body 30 has been parted from steel. The diamond grains (not shown in detail) protrude after completion of the existing galvanic treatment. A dressable grinding wheel could be bound with synthetic resin.

4, to which reference is also made, is a work area 34 shown in a further enlargement. The Grinding wheel 28 has a grinding or rounding radius R. A Part 34 'of the work area 34 is located in an end area and a part 34 "of the working area 34 lies in a cylinder area the grinding wheel 28. The grinding wheel 28 has a fixed geometry and is not dressable. If the downtime is at the end, the work area 34, i.e. the active Surface of the grinding wheel must be covered again.

3, the grinding wheel 28 has the Grinding or rounding radius R on the grinding edge, one Disc radius SR up to a tangent to the grinding edge, a disk height SH from a spindle bearing surface 36 to a tangent to the grinding edge, an inside angle IW one Inner surface (cone) 40 to the axis 38 of the grinding wheel 28 and an outer angle AW of an outer surface (cone) 42 to the axis 38. The working area 34 of the grinding wheel 28 is an annular surface, that of a point 44 as shown in FIG. 4 in the forehead area up to a point 46 in the cylinder area of the Grinding wheel 28 is sufficient and in that shown in Fig. 4 Axial section has an arcuate profile that extends over a Total contact angle GKW extends that in FIGS. 13 to 15 is shown and described in more detail with reference to these figures becomes. The total contact angle GKW is about 145 °. The arcuate profile is circular, and the radius of curvature is in a range of 0.5 to 5 mm and preferred from 0.5 to 1 mm.

The grinding wheel has in the entire working area 34 and the same abrasive coating, i.e. the different parts of the work area do not have to be coated differently to be used for roughing or finishing. The coating limits of the working area 34 are in 4 with 48 or 50, the respective one Overhang over which the coating limit over the actual Working range extends, with 52 or 54. The Angle within which the grinding wheel 28 with the head of the cutting knife 22 can come into contact during grinding, is called the head contact angle KKW. The head contact angle corresponds to the use of the grinding wheel 28 during roughing the part 34 "of the work area, and that for the Finishing part 34 'of the work area, as shown in FIG. 4 is drawn. The use of these different parts of the work area for roughing or finishing is as follows explained in more detail.

A cutting knife to be ground has three active surfaces on, namely two open spaces 56 (only one of which is shown in FIG is visible) and a rake face 58. These three faces can defined separately on the knife grinding machine 20 and then be ground separately. Every open space can be made two different surfaces (with two different Clearance angles and with two geometries). The technological Process can have multiple roughing cuts and one finishing cut include. Every technological phase (roughing or Finishing) or sparking can be defined separately.

13, 14 and 15 are the roughing and finishing technologies shown schematically. When roughing (Fig. 13 and 14) the cutting knife 22 is turned by a profile tilt angle PK tilted so that the work area 34 with the cylinder area the grinding wheel 28 is brought into contact. The on this Free space of the cutting knife generated in this way becomes concave the flank and cylindrical at the head of the cutting knife 22. At the generation grinding method described here is provided the "roughing surface" with a larger clearance angle than to grind the "finishing surface". 13 and 14 it can be clearly seen that the total contact angle GKW of the profile tilt angle PK is dependent. The profile contact angle Cars are in a range from alpha to 90 ° - alpha. For different Profile tilt angles PK are the different Parts 34 ', 34 "of the working area 34 of the grinding wheel 28 brought into contact with the cutting knife 22. In this way the roughing and finishing parts of the work area 34 of the grinding wheel 28 against each other or even separate from each other. The separation limit is PK = 90 ° - Alpha (with different grinding methods: bumping or Pull).

Fig. 14 serves to explain how the profile tilt angle PK the Total contact angle GKW shifts.

For the finishing phase, described with reference to FIG. 15 the knife profile is positioned vertically (PK = - Alpha). The grinding wheel 28 processes the flank of the cutting knife 22, where the generatrix is an arc in one plane is. A flat or cylindrical surface is created on the flank Facet whose width can be calculated. Only on the head of the cutting knife 22 no theoretically exact cylinder is generated, it but will give a correct cutting edge. The "Finishing clearance angle" is set smaller than for roughing, and the two different surfaces are created. For the machining process, the value of the "Finishing angle" agree. As mentioned above, by different positioning of the cutting knife 22 the different areas for roughing and finishing 34 "or 34 'of the grinding wheel 28 claimed, which increases the service life will lead. If the profile tilt angle PK being less than 90 ° - alpha is always an overlap area between roughing and finishing.

6 shows the cut distribution for a knife processing, where the removal only by infeed in the Y axis the machine. With this procedure, the removal is on the knife shoulder and at the knife tip much larger than on the side surfaces. Should it be due to the grinding technology be necessary for the removal to be approximately constant a suitable cut distribution must be calculated. Additional intermediate positions must then be in the correct position Sequence in a CNC part program with the correct time Sequence of grinding operations can be implemented. The additional Grinding operations are hatched in Fig. 6b marked.

The knife processing is shown below using the example of a Surface roughed in two passes and then is arbitrated with reference to FIGS. 7 and 8 in more detail described. For roughing in two passes with the cutting knife, which is shown in FIGS. 7 and 8 Clamping device 26, not shown (see FIG. 5a), is clamped has reached positions marked with 0-14 are. 7 is the first pass on the left and the one on the right shown second pass. The grinding wheel 28 retains their position at, and the positions shown are approached with the cutting knife 22 itself, although the representation in FIGS. 7 and 8 is chosen as if move the grinding wheel 28. However, this can, like the Representation in Fig. 1 shows only one movement in the Execute Y axis. The movements in the X, Z and if necessary in the Y axis, the clamping device 26 carries out in which the cutting knife 22 is clamped.

In Fig. 7, 0 is the home position from a standard position from collision-free. This Position corresponds to X = 0, Y = 0, Z = 0, with the effective one Zero offset. The dashed arrows mean a Rapid traverse, the solid arrows indicate feed.

The polygon point that is still approaching in rapid traverse is designated by 1 becomes. 2-6 are the path points of the first pass, which are started with feed. Points 7 and 8 are Intermediate points that are approached in rapid traverse. Points 9-14 are path points of the second round that are approached with feed become. From point 14, the withdrawal to Standard position in rapid traverse.

In Fig. 8, 0 is again the starting position, which from a Standard position can be approached without collision. 1 is the first railway point that is still approached in rapid traverse. 2-6 are the path points that are approached with feed. From the Point 6 is the return to the standard position in rapid traverse. 9-12 show, like that in FIGS. 7 and 8, schematically illustrated operations on the knife grinding machine 20 actually run.

In Fig. 9, the cutting knife 22 is set so that the Grinding wheel 28 with the part located in the cylinder area 34 "of their working area an area (A) of the cutting knife 22 grinds, namely roughing, starting from one Shoulder 21 to a head 23 of the cutting knife 22.

Fig. 10 shows the different possible grinding positions for different technological phases for grinding the Cutting knife 22 with the grinding wheel 28.

11, the other surface (B) of the Cutting knife 22 with the part located in the cylinder area 34 "of the work area ground, so also roughed.

According to the representation in FIG. 12, the previously is then Rough grinding machined surface of the cutting knife 22 in brought a vertical position in which to the forehead area the grinding wheel 28 is tangential. In this position this surface of the cutting knife 22 is finished.

The setting of the knife with respect to the grinding wheel movable in the Y-axis will now be described in detail with reference to Figs. 13-15. Of the grinding wheel 28, only the grinding edge is in each case in FIGS. 13-15
Circle indicated, which corresponds to the circle shown in Fig. 4 at the cutting edge. The grinding wheel, which is otherwise not shown, has the same orientation as in FIG. 4, ie its end face extends vertically and the axis of rotation is horizontal.

13-15 are the roughing and finishing technologies shown schematically. When roughing (Fig. 13 and 14) the cutting knife 22 is tilted by the profile tilt angle car, so that the profile with the cylinder area of the grinding wheel 28th is brought into contact. In this way, an open space generated which is concave on the flank and on the head 23 of the Cutting knife 22 is cylindrical. Preferably the "Roughing free area" with a larger clearance angle than that "Plain clear surface" ground. 13 and 14 is clearly recognizable that the total contact angle GKW of the Profile tilt angle is dependent on the car, as already explained above.

The knife profile becomes vertical for the finishing phase (Fig. 15) positioned (PK = - Alpha). The grinding wheel 28 processed the flank of the cutting knife with its end face at which the generator is an arc in a plane, as it is already explained.

As mentioned above, there are different positioning of the cutting knife when roughing and finishing different Parts of the working area 34 of the grinding wheel 28 claimed. The feed direction (pushing or pulling) plays a major role in this, of course.

a) Zuerst wird eine Fläche an dem Schneidmesser 22 durch Schleifen mit der Ringfläche unter einer ersten räumlichen Orientierung zwischen Schleifscheibe 28 und Schneidmesser 22 durch wenigstens eine erste translatorische Relativbewegung zwischen Schleifscheibe und Schneidmesser erzeugt, wie es für eine Fläche z.B. in Fig. 11 dargestellt ist, und

b) anschließend wird wenigstens ein Teil der erzeugten Fläche mit der Ringfläche unter einer zweiten räumlichen Orientierung zwischen der Schleifscheibe 28 und dem Schneidmesser 22 durch wenigstens eine zweite translatorische Relativbewegung zwischen der Schleifscheibe 28 und dem Schneidmesser 22 überschliffen, wie es in Fig. 12 dargestellt ist.

The method described above for grinding at least one surface on a cutting knife 22 used in machining technology with a grinding wheel 28 rotating about the axis 38, the working area 34 of which is an annular surface which has an arcuate profile in axial section (cf. in particular FIG. 4 ), can be summarized as follows:

a) First, a surface on the cutting knife 22 is generated by grinding with the ring surface under a first spatial orientation between the grinding wheel 28 and the cutting knife 22 by at least one first translational relative movement between the grinding wheel and the cutting knife, as is shown for a surface, for example in FIG. 11 , and

b) Subsequently, at least a part of the surface created is ground with the ring surface under a second spatial orientation between the grinding wheel 28 and the cutting knife 22 by at least one second translational relative movement between the grinding wheel 28 and the cutting knife 22, as shown in FIG. 12 ,

The first and the second are preferably spatial Orientation between the grinding wheel 28 and the cutting knife 22 by setting first and second positions of the cutting knife 22 in relation to the grinding wheel 28. Depending on the inclination of the cutting knife 22 in FIG. 12 is by the grinding wheel 28 of the at least part of generated area on the cutting knife 22 as a concave or just created facet. Expediently takes place during the generation the area on the cutting knife 22 is removed only by infeed in the Y axis of the machine. essential to the invention is that between the cutting knife 22 and the grinding wheel 28 only translatory relative movements performed become. Neither the grinding wheel 28 nor the cutting knife 22 needs to be turned during knife processing, apart from the rotation of the grinding wheel, of course by 28 around its own axis 38. The area on which Cutting knife 22 can in step a) and / or in the Step b) in two passes through two first and second translational relative movements between the grinding wheel 28 and the cutting knife 22 are generated.

It has already been stated above that the method is preferred executed on a CNC machine and that to determine of interrelations between geometric and technological Parameters for the generation loop of a CDS computing system is used. An example is further described above that the area on the cutting knife 22 in the Step a) in two passes, i.e. with two roughing cuts is produced. But it is clear that at least one roughing cut is sufficient. The at least part of the generated Surfaces are then in step b) with a finishing cut reground.

The translational relative movement between the grinding wheel 28 and the cutting knife 22 is produced in that the Cutting knife 22 an impact movement relative to the grinding wheel 28 (such as shown in Figs. 13 and 14) or one Pulling motion (such as shown in Fig. 15) is given. The special advantage of the grinding wheel 28, which in this case described method is that the Grinding wheel in its entire used for grinding Ring surface has the same specifications, i.e. that the Grinding wheel in the entire work area, for example has one and the same abrasive coating, and that the selection of roughing and finishing cuts simply by selecting of feed parameters such as feed direction and speed, Cutting speed and oversize takes place.

The surface elements of the ring surface, which in steps a) and b) used for roughing or finishing are against each other interchangeable.

The method described here is preferably used to using a diamond cup grinding wheel carbide knife to grind.

The grinding wheel 28 can be dressable or non-dressable his.

• Abrichten mit einer Konturrolle 66 (Fig. 16a), welche die negative Korrektur besitzt. In diesem Fall sind außer dem Anfahren an die Schleifscheibe 28 keine weiteren Achsbewegungen nötig, oder
• Abrichten mit einer Konturrolle 68, welche eine ähnliche Kontur besitzt, wie sie üblicherweise verwendet wird. In diesem Fall muß mit der Konturrolle 68 eine Kontur um das Scheibenprofil gefahren werden.

If a dressable grinding wheel is used, the dressing could be carried out in the following ways:

• Dressing with a contour roller 66 (FIG. 16a) which has the negative correction. In this case, no further axis movements are necessary, except for moving to the grinding wheel 28
• Dressing with a contour roller 68 which has a contour similar to that which is usually used. In this case, the contour roller 68 must be used to trace a contour around the window profile.

Because of the inclined dressing spindle axis, this can usually existing arrangement of the dressing unit is not adopted for this become. The controller must be notified with a new input signal be that the dressing device (contour roller 66 or 68) was set up for the diamond cup grinding wheel, see above that software range limit switches can then be activated and additional monitoring and plausibility checks regarding of the grinding process can be carried out. FIG. 16a schematically shows the conditioning with the contour roller 66 and with linear interpolation when approaching the grinding wheel contour. 16b shows conditioning with the contour roll 68 by interpolation around the grinding wheel contour. In both cases, the conditioning process can be different Relative speeds of the contact points of the cup wheel to the dressing tool in order to achieve the desired Surface quality or abrasion ability of the grinding wheel 28 to reach. The actual dressing process is carried out in the CNC stored cycle, which is based on the data of the tool database accesses. The conditioning process according to Fig. 16b can are executed if the condition for the radii and the Steepness of the cone is satisfied. Then find one theoretically punctiform contact between the grinding wheel 28 and the Dressing roller 68 instead. The dressing cycle must be designed so that a dressing roller with a cylindrical part and one radius each can be applied to the edge.

Above it is stated that at least two translational movements are necessary, namely one for the flank of the cutting knife 22 and one for the head 23 of the cutting knife 22, it could, however, additionally with a third translational movement be worked.

The optimization involved in the generation grinding process described here can be made, for example, in it exist that the force on the grinding surface remains constant. To achieve this optimization, it is e.g. possible that To design surfaces on the cutting knife 22 so that the cutting performance the grinding wheel 28 always remains the same. The Grinding wheel manufacturers usually recommend a specific one Cutting performance that should be maintained. For the The user then has the option of grinding the knife surfaces to adapt to it. A controlled division of cuts, as described above with reference to FIGS. 6a and 6b enables a better optimization of the grinding process, namely constant performance or forces, manufacturing a desired facet width etc.

Another optimization is that the ground Surface in the final state can be either flat or concave and that each open space itself is a combination of two open spaces can exist. For this, only the spatial needs Orientation between the grinding wheel 28 and the cutting knife 22 to be chosen accordingly, combined with one Pushing or pulling movement of the cutting knife 22, as set out above. The method described here is therefore extremely flexible.

Industrial applicability

With a grinding wheel rotating around an axis Working area is an annular surface that is in axial section has an arcuate profile, is on a cutting knife first a surface by grinding with the ring surface below a first spatial orientation between the grinding wheel and cutting knife by at least a first translational Relative movement between them is generated and then at least a part of the generated area with the annular surface under a second spatial orientation between Grinding wheel and cutting knife by at least one second translational relative movement between them reground. The grinding wheel is a diamond cup grinding wheel. The work area is in part with a forehead area and with another part in one Cylinder area of the grinding wheel. One part is used for Rough grinding, and the other part is used for Finishing grinding of those to be produced on the cutting knife Area. The grinding wheel points in the entire work area one and the same abrasive coating. The roughing and Finishing is done using areas of Grinding wheel that have the same specifications, but with different grinding parameters. The choice of spatial Orientation between grinding wheel and cutting knife preferably by adjusting the cutting knife in relation to the grinding wheel. The method allows the generation of Surfaces on a cutting knife that are flat and / or concave allows a simpler workflow and the Use of a grinding wheel with a simpler configuration than in the state of the art.

Claims (19)

1. A method for grinding at least one surface on a cutting blade (22) used in machining, with a grinding wheel (28) that rotates around an axis (38) and that has a working area (34) consisting of an annular surface having a circular arc profile in axial cross section, comprising

   a) generating a surface on the cutting blade (22) by grinding with the annular surface during a first orientation in space between the grinding wheel (28) and the cutting blade (22) by means of at least one first relative translational movement between the grinding wheel (28) and the cutting blade (22), and

   b) regrinding at least one part of the generated surface with the annular surface during a second orientation in space between the grinding wheel (28) and the cutting blade (22) by means of at least one second relative translational movement between the grinding wheel (28) and the cutting blade (22).
2. The method according to claim 1, characterized in that
   in the step a) the first orientation in space between the grinding wheel (28) and the cutting blade (22) is obtained by setting a first position of the cutting blade (22) in relation to the grinding wheel (28), and in that
   in the step b) the second orientation in space between the grinding wheel (28) and the cutting blade (22) is obtained by setting a second position of the cutting blade (22) in relation to the grinding wheel (28).
3. The method according to claim 2, characterized in that
   the first position of the cutting blade (22) is selected such that the grinding wheel (28) generates the surface on the cutting blade (22) with a first surface element of the annular surface located in a cylinder area of the grinding wheel (28), and in that
   the second position of the cutting blade (22) is selected such that the grinding wheel (28) grinds the at least one part of the surface generated on the cutting blade (22) with a second surface element of the annular surface located in a face area of the grinding wheel (28).
4. The method according to claim 3, characterized in that
   the second position of the cutting blade (22) is selected such that the grinding wheel (28) generates the at least one part of the surface generated on the cutting blade (22) as a concave or planar facet.
5. The method according to any of the claims 1 to 4, characterized in that
   the stock removal during generation of the surface on the cutting blade (22) occurs only through infeed in a Y-axis of the machine.
6. The method according to any of the claims 1 to 5, characterized in that
   the surface on the cutting blade (22) is generated only with three mutually orthogonal linear axes (X, Y, Z), and other axes (C, A) are utilized merely as adjustment axes and are positioned prior to the actual generating grinding of the surface on the cutting blade (22).
7. The method according to any of the claims 1 to 6, characterized in that the surface on the cutting blade (22) is generated in step a) and/or in step b) in two operations by means of two first and two second relative translational movements between grinding wheel (28) and cutting blade (22), respectively.
8. The method according to any of the claims 1 to 7, characterized in that
   the method is carried out on a CNC blade grinding machine (22).
9. The method according to claim 8, characterized in that
   a CDS computer system is used to determine interrelations between geometric and technological parameters for the generating grinding.
10. The method according to any of the claims 1 to 9, characterized in that
    the surface on the cutting blade (22) is generated in step a) with at least one roughing cut, and in that
    the at least one part of the generated surface is reground in step b) with a finishing cut.
11. The method according to any of the claims 1 to 10, characterized in that
    the relative translational movement between the grinding wheel (28) and the cutting blade (22) is produced by imparting a thrust or pulling motion to the cutting blade (22) relative to the grinding wheel (28).
12. The method according to claim 10, characterized in that
    in the regrinding with a finishing cut a pulling motion relative to the grinding wheel (28) is imparted to the cutting blade (22).
13. The method according to claim 10, characterized in that
    a grinding wheel (28) is used having the same specifications throughout its annular surface used for the grinding, and in that
    the roughing and finishing cuts are selected solely through selection of feed parameters such as direction and rate of feed, overmeasure, and grinding speed.
14. The method according to claim 10 or 13, characterized in that
    roughing and finishing in steps a) and b), respectively, and thus the surface elements of the annular surface used for grinding are interchangeable.
15. Use of the method according to any of the claims 1 to 14 using a diamond cup-type grinding wheel (28) to grind cemented carbide blades (22).
16. A grinding wheel for carrying out the method according to any of the claims 1 to 15, the grinding wheel (28) comprising a diamond cup-type grinding wheel with a working area (34) having one part (34') located in a face area and one part (34") located in a cylinder area of the cup-type grinding wheel, the working area (34) consisting of an annular surface having a circular arc profile in axial cross section which extends over a total contact angle (GKW), and the grinding wheel having one and the same abrasive coating (32) in the entire working area (34), characterized in that
    the total contact angle (GWK) is approximately 145° and that the circular arc profile has a radius of curvature (R) lying within a range of 0.5 to 5 mm and preferably of 0.5 to 1 mm.
17. The grinding wheel according to claim 16, characterized in that
    the grinding wheel (28) has a fixed geometry and is nondressable.
18. The grinding wheel according to claim 17, characterized in that
    the grinding wheel (28) comprises a metallic carrier body (30) onto which an abrasive coating (32) of diamond grit and a galvanic bonding consisting of nickel is applied, with the diamond grit protruding from the galvanic bonding.
19. The grinding wheel according to claim 16, characterized in that the grinding wheel (28) is dressable.

Images