DE10114240A1 - rotary tool - Google Patents

Abstract

The invention relates to a tool arrangement, in particular for machining with high-speed machines, comprising a holder with a machine shaft for receiving in a work spindle of a machine tool and a slim tool shaft, with a bore penetrating both shafts in the area of and essentially concentric to its longitudinal central axis and a tool therefor and a method for producing the tool and the use of a cutting body. An interchangeable cutting body made of hard material is pressed with an integral spigot or a spigot is fitted to the rear with a precise fit, then the cutting edges are ground in and the spigot is provided with at least one joining area for the fitting in a complementarily designed holder of a tool arrangement. The cutting body is preferably provided with a recess for the engagement of a driving lug on the holder.

Description

The invention relates to a tool arrangement, in particular for cutting Machining with high-speed machines, including a holder with machine shaft for mounting in a work spindle Machine tool and a slim tool shank, with one both Shafts penetrating hole in the area and essentially concentric to its longitudinal central axis and a tool for it as well as a Method of making the tool and the use of a Cutting body.

In the VDI-Zeitung, Special Tools, May 2000, VDI-Verlag Germany a modular tool system has been presented, comprehensive Solid carbide milling heads that are shaped using a special clamping technology and are non-positively attached to standardized steel shafts. Such a tool is to be used for highly dynamic drive. Clamping variants for similar tools are shown in EP 0 298 937 A1. The tool has what is known as a Weldon shank Clamping body on the corresponding in the drive spindle Milling machine can be used. This shaft has an internal thread, into which an adapter with an external thread is inserted. This Intermediate piece points to the side of the milling head to be picked up Driving nose on which in a complementary nose Milling head can engage, so that milling head and intermediate piece together can be screwed into the shaft with the help of one of the Machine side through a hole in the tool. By an essentially conical shape of the tool shank is the Milling head together with the intermediate piece and transversely to the longitudinal axis of the tool, while in the longitudinal axis of the form fit between the intermediate sleeve and the milling head as well as via the thread the shaft is generated. So there are three fits between the Machine and the tool shank as well as the tool shank and the Intermediate piece and ultimately between the intermediate piece and the one-piece carbide milling cutter, resulting in a correspondingly high Manufacturing effort for an exact concentricity leads. Instead of The hook on the adapter can also be used with a adapter T-groove provided, in which a complementarily shaped end of the Milling head can be used. It is also mentioned that instead of the Screwing the adapter into an internal thread in the Tool shank, the tool shank also with a pin that External thread, can be provided so that the intermediate piece Internal thread can be screwed over such a pin.

A similar situation is shown in WO 00/37204, in which a one-piece tool, for example a face milling cutter, with a Intermediate sleeve can be screwed onto a tool shank.

In a modified embodiment, such a clamping is one Milling head also shown in WO 98/13161. One is also mentioned Bayonet lock instead of a thread. In these cases the Milling head shaped so that it is in face contact with part of its back surface rests on the end face of the tool shank, while a center hole in the shaft is a complementary one cylindrical extension of the milling head. This is complex Incorporation of the thread into the carbide milling cutter and an exact Double fit through the matching thread in combination with the face contact and the centering of the milling head on the shaft.

EP 0 109 369 A2 discloses a fastening for a rotary tool, For example, a milling cutter is known, in which the rotary tool in a cylindrical receptacle of a mandrel, which in turn in a Machine spindle of a machine tool can be added. The holding mandrel points laterally in its holding part for the tool Openings in which wind pins can be screwed in and in a groove is formed on the tool shank (Weldon- Connection).

EP 0 820 826 A1 describes an extension sleeve instead of one Known shaft with Weldon attachment for a processing tool, which are inserted into a spindle of a processing machine can. The extension sleeve has a through hole constricting paragraphs in which a milling head with a corresponding Shank can be inserted from the machine side. The back of the sleeve is closed by a spring-loaded screw, so that the milling cutter is held securely in the machining position in the axial direction. A rotational fixation is only achieved by friction and not by Takeaway. The frictional forces depend on the tension of the screw closes the extension sleeve and holds the milling head. Alternatively, the tool should have a milling head on its back with a Be provided shaft part on which an external thread is applied. On this external thread can be screwed to an intermediate piece, after which the shaft was inserted into the extension sleeve and with its the conical part upstream of the shaft in a complementary shape Batch of the extension sleeve fits.

EP 0 911 103 A1 describes a modular system for clamping in a spindle a processing machine specific mounting part according to Art known a tool shank on which an exchangeably fastened Milling head with a hollow cylindrical extension at the rear can. For this purpose, the shaft has an opening arranged in the longitudinal axis which ends on the tool side on a relatively thin shank part. On this thin shaft part becomes a correspondingly shaped milling head slipped on and fixed to the shaft with drivers and then one before mandrel threaded into the hollow shaft with an am Tool end provided thickening by means of a Machine side of the shaft arranged screw in the shaft pulled so that the thickening spreads the relatively thin shaft part and non-positively in operative connection with the put-on milling head.

From EP 0 285 704 A1 is a multi-part clamping system for concentric Tools known, which on the machine side on a work spindle can be attached and to the tool side with a radial through one transverse bolt spreadable segment ring by positive locking a complementary part of the tool this in Can fix the axial direction positively. However, a is shown Intermediate piece, which in a tool body with appropriate Hole is screwed in and this intermediate piece is then through the Fixed segment ring. Furthermore, the Milling head, or tool head, by means of pins in the shaft held positively.

EP 1 013 367 A2 discloses a drilling tool in which the tip is interchangeable, in the manner of a bayonet lock in one correspondingly complementary designed shaft with molded Undercut is used and fixed.

WO 96/34714 proposes a for a drilling tool interchangeable tip to use. A commercially trained, with Clamping grooves in the shaft of one in a work spindle Machine tool is attachable, the tip is attached so that the rear surface of the drill bit with a groove configuration is provided, which is complementary to a corresponding head surface on Shaft is formed. This takes the tip away Form-fit guaranteed when the tip is also secured in the axial direction is. This is done through a hole in the shaft through which a Mandrel is inserted from the machine side, which on Its tip has an external thread that is complementary configured internal thread of the drill bit can be screwed in.

From European patent applications 0 443 102 A1 and 0 123 156 A2 Multi-part clamping systems are known, in which by means of a spindle or a pull rod in a dome suitable for a work spindle an intermediate piece is fixed, which on the tool side as the receiving carrier is designed for a tool. The intermediate piece and the Tool carriers are in turn connected by a thread connected, with additional drivers for the tool head be provided, which a power transmission by positive locking allow rotational movement of the tool.

A NOVEX® milling tool (brand from Walter AG, DE) known, comprising a milling head made of hard metal with a cylindrical Pin, as well as one for clamping the tool in one Work spindle suitable holder with machine shaft, which for Tool side a complementary to the pin of the milling head Has receiving hole into which the pin is shrunk.

Based on the prior art, the invention is the problem based on avoiding the disadvantages of the prior art, the Advantages, however, especially the use of carbide milling heads or similar tools, but a simpler and cheaper one Propose fastening technology. These and other problems with them the invention deals with those skilled in the art through the description the invention and the drawing apparently.

The problem is solved according to the invention by the features of Claims 1, 13, 15, 18, 19, 20. Further developments of the invention are in the Subclaims recorded.

Today's technology instead of working with different degrees of precision Machines for roughing, finishing and grinding during machining often tools with small cutting edges that run at top speed work with up to 30,000 and more revolutions while being highly precise Also create surfaces in bores. The used for this Solid carbide tools are intended according to the invention by tool systems are replaced, in which only a few, ideally only two, components for the Tool head and holder are used, and so the expensive Solid carbide tools or several intermediate parts with difficult Replace fits to be made between cutting head and holder.

The invention relates first to a solution for Fasteners or fasteners on the tool head or Cutting head; representative of milling cutters, reamers, honing tools and In the following, the drill will use the solution on a cylindrical milling head a variety of cutting edges. Furthermore, the Invention on a holder suitable for the tool head, which on its tool end basically complementary to one Connection element is formed on the tool head and a Has machine shaft that on the work spindle of the Machine tool can be attached. The type of used Machine shafts are almost arbitrary, but are standardized Inexpensive holder preferred, depending on the requirement of the cutting Machining and, depending on the type of connecting elements, both holders made of steel as well, at least for the tool shank, made of hard metal or for z. B. high-precision concentricity made of heavy metal such as tungsten or others Metals and metal alloys are used.

The tool head or the tool consists of a cutting body made of hard material with an inseparably attached connecting element for a Connection with a holder. It is a consumable part for mass production designed and will be replaced by a new one after the cutting has been processed Tool replaced. Due to the design, it is suitable for drilling from approx. 10 mm to 50 mm and corresponding face milling or other milling work suitable.

Today, geometrically determined cutting tools are made up of a large number made of different cutting materials, according to their Material properties across different application areas in the Machining technology.

According to the invention, cutting materials, hard materials such as hard metal, PCD (polycrystalline diamond), cermets, ceramics, PCBN (polycrystalline cubic boron nitride) are used, which in corresponding cases PCD or CBN layers, applied by PVD, CVD Coating process can have.

The manufacture of the tools or cutting inserts takes place predominantly by powder metallurgical processes. Starting from synthesized Powders are molded, so-called green compacts, which in a subsequent sintering process. Although the Powder metallurgy is already making manufacturing complex and extensive Post-processing of the final contour of close tool geometries is permitted of the sintered blanks is necessary in most cases because the achievable Shape and dimensional accuracy as well as edge quality for the Use as cutting tools are inadequate.

This finishing not only decides on the dimensions and Shape accuracy of a tool, but decreases due to the thermal and mechanical loads during processing also influence the edge zone properties of the machined workpiece, such as Sharpness in edges, hardness, residual stress or the appearance of Microcracks.

Hard coatings have become the state of the art for Functional improvement of cutting tools implemented. Next increased tool life and increased cutting speed will also be a Improved surface quality of the workpiece.

The characteristic of the cutting materials mentioned and at the same time limiting dualism, high hardness and wear resistance or high Bending strength and toughness can increase in many cases essential parts by coating substrate material be overcome. This principle of separation of functions combined wear-resistant layers with - to a certain extent compared to HSS material - tough Base. Because of the large temperature differences in machining Tools occur is the mastery of thermally induced cracks Sequence of different coefficients of thermal expansion Prerequisite for durable, crack-free layers important. Coating and multiple coating can be inexpensive Achieve combinations of properties. To the well-known Coating processes include CVD (Chemical Vapor Deposition) and PVD (Physical Vapor Deposition). PVD coatings require in Lower compared to conventional CVD coatings Temperatures, but they are subject to tool geometry certain restrictions while. In contrast, the conventional CVD coatings due to the high Coating temperature problems; the plasma CVD process (PACVD) allows the coating temperatures to be lowered.

These manufacturing variants and temperature influences force you to choose adapted materials and fastening techniques for pairing Cutting body / connecting element / holder.

The pairing of hard metal and hard metal hardly allows shrinking but sticking and soldering, while a connecting element - preferably - made of steel easily allows shrinking and shrinking in the holder and at the same time can be easily soldered into a carbide cutting body. The person skilled in the art knows the combinations which can be used advantageously.

The invention will be explained in more detail with the aid of a schematic drawing become. Show it:

Fig. 1a-f embodiments of the invention with different expressions of a peg-shaped connecting member attached with threaded portion;

FIG. 2a-b embodiments of the invention with different expressions of an attached sleeve-like connecting element threaded portion;

Fig. 3 shows a cutting body with an integral pin and entrainment, shrink wrapped in a holder,

Fig. 4 shows a cutter body with attached sleeve and entraining, shrink wrapped in a holder,

Fig. 5 shows a cutter body with attached pin and entrainment, shrink wrapped in a holder,

Fig. 6a-c, two different tool assemblies with a tool,

Fig. 7a-k tool and five clamping devices in tool assemblies,

FIG. 8a-b tool assembly with a tensioned cutting body.

The following are for identical or equivalent functioning parts the same reference numerals are used to describe the invention in principle clarify.

In the drawing, a cutting body 1 with a plurality of ground-in cutting edges made of hard material, for example full PCD, is shown with a connecting element 2 , with which it is clamped in the tool shaft 3 of a holder. The holder is in turn provided with a machine shaft 10 and a device 11 for clamping the holder in a machine tool, not shown.

The cutting body 1 is provided with a cylindrical recess 11 , which is located within an annular surface 12 on the rear part of the cutting body ( Fig. 1a, c, 2a, b, 4, 5). In Figs. 1b, e, f and 7a, the recess is conically formed in the same position. A connecting element 2 has a corresponding pin with an annular end face 26 and a cylindrical or conical surface 27 in a complementary and precisely fitting manner. The inner surface of the depression 11 and the surface 26 are connected to one another by solder, so that the tool is in one piece. Instead of or in addition to the surfaces mentioned, the adjacent ring surfaces can also be connected by soldering or other corresponding methods. To improve the power transmission in the sense of a driving property, the contacting end faces on the cutting body and connecting element with roughened layers, for. B. introduced diamond powder. Shrinking, welding, gluing or sintering can also be used as the connecting method, the material of the connecting elements being important, as the person skilled in the art knows.

In Fig. 1a, the element 2 is designed as a pin, in the case of Fig. 2a, b as a sleeve towards the holder side.

For precise joining because of the desired very precise concentricity of the tool and the possibility of quickly replacing the one-piece tool with another after the cutting edges have been used, the connecting element has a precisely fitting joining area 8 or, in the case of two joining areas lying one behind the other, also 8 'with an intermediate thread 7 . The joining areas can be double-conical as in Fig. 1a, 2a, simply conical according to Fig. 1d, f, 3-6,7a, h or double cylindrical according to Fig. 2b, simply cylindrical according to Fig. 1b, c, e, 7b-e with correspondingly precise guidance.

The tool according to FIGS. 1a, 2a, b can thus be simply screwed onto the complementarily designed holder, this entire tool arrangement being traversed by a coolant bore 6 .

Be according to Fig. 1b, c, e may be supplemented simply cylindrical guide 31 in the joining region 8 by a planar abutment 31, the end faces of the holder and tool / connector element or as shown in FIG. 1d, a cylindrical combined with a conical guide between the components 2 and 3 , In FIGS. 1b-f, 6 and 7, the tool 1 by means operated from the machine side pull rod 5 with thread 7 which engages in corresponding thread on the connecting element, are fixed to the holder 3.

FIG. 1b, df, 3-7 show the use of entrainment preferably 4 between the holder 3 and the tool 1, 2.

Fig. 3-5 show variants in which the connecting element is conically formed in one piece in an integral form with the cutting body ( Fig. 3) or in an attached form ( Fig. 4, 5) and shrunk onto or onto the holder. The joining areas 8 , the surfaces 31 on the holder and the surfaces 21 , 22 on the connecting element then naturally have a corresponding press fit.

In Fig. 6a-c the connecting element 2 is formed by an intermediate member in the form of a chuck 9 which engages around the pin 91 and is guided in part 92 (Fig. 6a and offset by 90 degrees in Fig. 6b) while in Figure ., the pin is enclosed with thread 7 by a sleeve 52 with internal thread 6c, wherein the sleeve is coupled to the pull rod 5 by the pin 51.

In principle, a tool according to FIG. 7a is used in the tool arrangement according to FIGS. 7b-7g. In Fig. 7b-e part 2 and draw bar 5 are coupled to intermediate member 53 by bolts 42, 7b at the same time lying acts of FIG. In the groove 41 as a driver, During in Fig. 7c, the holder d a separate drive lug 4 has, which engages in the cutting body 1 in a recess.

Referring to FIG. 7e, the bolt 42 can also pass through the holder to facilitate assembly. In Fig. 7h-k, a tool holder is shown with shaft 35 made of heavy metal, which is coupled as an expensive item to the machine shaft 10, 11. The sections AA in FIGS. 7i and 7k show an alternative embodiment of driver devices on the holder / tool.

Fig. 8 shows a tool with integral formation of the cutting body 1 and connecting member 2 in combination with a holder 3, wherein the tool is screwed the threaded bolt is fixed in a draw bar 5 or in the holder 3 itself by means of the front forth.

Claims (20)

1. Tool for machining with High speed machines, comprehensive a cutting body made of hard material with three or more cutting edges and a connection element that is inextricably coupled, precisely manufactured made of steel, with the cutting body at the back a has an annular surface which has a to the longitudinal central axis of the Tool is rotationally symmetrical and within an annular surface molded recess with wall surfaces that surround with essential parts of complementary surfaces within an annular surface of the connecting element and / or to the Ring surfaces by soldering, welding, sintering, shrinking or Adhesive are inextricably linked, with at least parts of the Ring surfaces lie flat against each other. 2. Tool according to claim 1, characterized in that the Recess cylindrical, conical or conical-cylindrical is. 3. Tool according to claim 1 or 2, characterized in that the Has deepening steps. 4. Tool according to one of the preceding claims, characterized characterized in that the connecting element for the positive Attach to a tool holder in a spigot that ends preferably a thread or an opening transverse to Has central axis. 5. Tool according to one of the preceding claims, characterized characterized in that the connecting element for the positive Attach to a tool holder in a spigot that ends a precisely fitting concentric joining area and one Has return to take a driver. 6. Tool according to one of the preceding claims, characterized characterized in that on the connecting element of the pin Thread has an internal thread or external thread, which on the shaft side behind a joining area with a precisely fitting contour on Pin is arranged. 7. Tool according to one of the preceding claims, characterized characterized in that the joining area at least one as a cylinder or has a cone or a section of equal thickness. 8. Tool according to one of the preceding claims, characterized characterized in that the joining area is divided into sections. 9. Tool according to one of the preceding claims, characterized characterized in that another joining area towards the holder itself the thread connects. 10. Tool according to one of the preceding claims, characterized characterized in that the connecting element for the positive Attach to a tool holder as a sleeve to hold a complementary formed on the holder concentric pin is trained. 11. Tool according to one of the preceding claims, characterized characterized in that the cutting body is selected from the Cutting material group, including hard metal, cermets, ceramics, solid PCD, PCBN and with PCD or CBN or nano layers provided cutting materials, preferably applied by PVD or CVD coating process. 12. Tool according to one of the preceding claims, characterized characterized in that the cutting body and the Connection element with a continuous coolant hole are provided. 13. Tool arrangement, in particular for machining with high-speed machines, comprising
a holder with machine shaft for receiving in a work spindle of a machine tool and a slim tool shaft, with a bore penetrating both shafts in the area of and essentially concentric to the longitudinal central axis,
a one-piece tool consisting of a cutting body and a connecting element permanently attached thereto, in particular tool according to one of the preceding claims, which can be locked in a form-fitting manner in the holder by means of a pull rod to be operated from the machine shaft,
the holder being equipped with a precisely fitting joining area for parts of the connecting element, which extends in the axial direction in the end region of the tool shaft, and a driver device for the tool on the holder and / or the pull rod. 14. Tool arrangement according to claim 11 or 12, characterized through a tool shank that is at least partially made of hard metal or heavy metal such as tungsten or other metals or Metal alloys exist. 15. Tool arrangement, especially for machining with High speed machines, comprehensive a holder with machine shaft for inclusion in one Work spindle of a machine tool and a slim one Tool shank with a hole penetrating both shafts in the Area of and essentially concentric to the longitudinal central axis, a one-piece tool from a cutting body, in particular of material according to claim 5, and an insoluble thereon attached connecting element, in particular tool after one of the preceding claims, which in the holder is positively and shrink-locked, the holder being aligned with the central axis, preferably conical centering for at least sections of the Connecting element, which is in the end region of the Tool shaft extends in the axial direction, and one Driver device for the tool is equipped. 16. Tool arrangement according to claim 15, characterized by a tool shank made entirely of steel. 17. Tool arrangement according to claim 13 or 15, characterized through a tool consisting only of cutting material the cutting body and an insoluble part through integral molding Connecting element. 18. Tool arrangement, especially for machining with High speed machines, comprehensive a holder with machine shaft for inclusion in one Work spindle of a machine tool and a slim one Tool shank with one the tool and at least partially the Tool shaft penetrating hole in the area of and in essentially concentric to the longitudinal central axis, a one-piece Tool from a cutting body, in particular from material according to claim 5, and an indissolubly attached thereto Connecting element, in particular tool according to one of the preceding claims, or integral with the cutting body trained connecting element, the holder being aligned with the central axis, preferably conical, centering for parts of the Connecting element, which is in the end region of the Tool shaft extends in the axial direction, and a driver is equipped for the tool and a lanyard Tool reaches through fixed in the holder. 19. A method for producing a tool according to one of the preceding claims with the following method steps:
Production of a cutting body made of hard material,
Producing a recess in the rear part of the cutting body for a connecting element,
Joining the cutting body with the connecting element,
Grinding the cutting edges,
optionally coating the cutting body. 20. Use of a cutting body made of hard material with an integral or attached pin as a connecting element to Shrinking the cutting body into a complementary one Trained holder for the cutting body, the pin too is tapered towards the end, into the cutting body Recess introduced and the holder with one in the recess gripping nose is provided.