DE2424033A1 - Tool producing tooth elements on cylindrical workpieces - has two groups of profiles one between guide and slide ends - Google Patents

Abstract

Tool for producing tooth elements on the periphery of a cylindrical workpiece by pressure deformation, consisting of the actual tool body with guide and slide ends and a working face, which has a number ot tooth profiles. A first group of tooth profiles is arranged between the guide end and the slide end and each tooth element in this first group has a profile which corresponds with the profile of the teeth to be formed on the workpiece. A second group of tooth elements is arranged between the guide ends of the tool and the first group of tooth elements and the tips and roots of the teeth of the second group are defined by radii.

Description

Lawyers KRIFGFR · FOTHE · PINDHR ^Baro: «« «^« * ™ ββ »

Dr. jur. Hans Krieger 4000 Düsseldorf 1 Telex: 0858/7428 ttfcr

Dr. jur. H. Jochen Krieger. Cable: Jurk Düsseldorf

Dr. jur. A. Reinhard Rothe PO Box 6808 ET * ^nw '5 ™ ^kl £? ° -J?'"? ™haben

Kreissparkasse D there No. 1039725 Dr. jur. Wolfgang Pinder postal check: Essen No. 3572-431

Applicant: EX-CELL-O CORPRATION

2855 Coolidge, Michigan 48p84 / USA

Tool for the production of tooth profiles

The invention relates generally to tools for making tooth profiles and, more particularly, to an improved tool for the production of spring teeth, gear teeth, worm gears, Serrations and the like on the circumference of a cylindrical workpiece by compression deformation, the workpiece to be machined is kept at ambient or room temperature and no material is removed from the workpiece.

Tools of this type are already known, that is to say those with the aid of which the above-mentioned tooth profiles or serrations can be generated on the circumference of a workpiece at ambient or room temperature and without material removal

KDQQ /. O / η ο «ο

Lawyers KRIcGER · ■ ROTHE · PINDHR X ^ "J £ S £ ³²

Dr. jur. Hans Krieger $ ₀₀₀ Dusseln 1 I ^{e 'ex:}

Dr. jur. H. Jochen Krieger η i ί ΓηΙ _rf κ,, «, **

' ^a Dnotfonk CQOQ Dresdner Bank, D dorf No. 2521404

Dr. Jur.A. Reinhard Rothe P.O. Box 6808 Kreissparkasse D'dorf No. 1039725

Dr. jur. Wolfgang Pinder postal check: Essen No. 3572-431

can. Examples of such tools, which have also been used with success in practice, are in the US-PSs 2 994 237 and 3 o15 243 derived. These tools can, for example, be used in work machines, as they are in U.S. Patent 2,995,964.

According to the present invention, a tool for the production of tooth elements or tooth profiles is now available proposed the circumference of a cylindrical workpiece by compression deformation, which consists of the actual tool body with sliding and leading ends as well as a work surface with a variety of tooth profiles and which is characterized in that a first group of tooth profiles between the leading end and the sliding end of the tool is arranged, and each tooth element in this group has a profile that corresponds to the profile of the forming teeth on the workpiece, and that between the leading end of the tool and the first Group of tooth elements a second group of tooth elements is arranged, the tooth tips and tooth roots are defined by radii.

In a preferred embodiment of the invention are between the leading end of the tool and the second Group of tooth elements arranged a third and fourth group of tooth elements, their tooth tips and tooth roots are also defined by radii and where the radius of the tooth tips of the third group is greater is larger than the radius of the tooth tips of the second group and the radius of the tooth tips of the fourth group is than the radius of the tooth tips of the third group.

ι r \ ^ y * <^

Lawyers, KRIEGER vROTHE-PINDfR

Dr.'juir. Hans Krieger * 000 DüS3eMo4i IT,

Dr. jur. H. Jochen Krieger _ ■ _ ' ΚΪΑΪΚΪν ^ ««

Dr. Jur. A. Reinhard Rothe ■ '■■ ; ■ ■ -. P.O. Box 6808,, Kreissparkasse D'dorf No. 1039725

Dr. jur. Wolfgang Pinder. Postal check: Essen No. 3572-431

24240p

In other words, are located between the leading end the tool and a first group of tooth elements, the profile of which corresponds to that of the teeth to be formed, further groups of tooth elements, the tips of which are defined by radii, these radii from group to group increase as this group approaches the leading end of the tool.

It is particularly advantageous if the radii of the roots of the teeth in the third group are also larger than that Root radii of the teeth of the second group and the radii of the roots of the fourth tooth element group are larger than the corresponding radii of the third group.

A further improvement of the invention is given by the fact that the tips of the teeth of the second group below the tooth tips of the first group, the tips of the teeth of the third group below the tooth tips of the second group and the tips of the teeth of the fourth group below the tooth tips of the third Group to lie grain- ^ men. ^

The root line of the teeth of the second group is preferably above that of the teeth of the first group, the root line of the teeth of the third group above that of the teeth of the second group and the root line of the teeth of the fourth group above those of the teeth of the third group.

Finally, it is advantageous if there is another group of teeth near the leading end of the tool, whose individual teeth are sharp-edged.

Lawyers KRIEGER · ROTHE · ΡΙΝΟΓΡ

Dr. jur. Hans Krieger "000 Düsseldo-t 1 Telex: 0858/7428 ttkr

Dr. jur. H. Jochen Krieger * ^abe ' ^{: Jur} _n ^k ^ ⁰ '"* ⁰ * '

' ^a [! ..! („„ ι, cono Dresdner Bank, D there No. 2521404

Dr. jur. A. Reinhard Rothe P.O. Box 6808 Kre.ss _P arkas _S e D'dorf No. 1039725

Dr. jur. Wolfgang Pinder postal check: Essen No. 3572-431

2A2A033

Due to the increase in radius sizes according to the invention in Direction towards the leading end of the tool is not only essential to the strength and service life of the tool itself improved, but it also happens due to the increase in the flow characteristics of the material to be processed Workpiece metal, for a significantly better design of the tooth profile on the workpiece.

The invention is explained below with reference to the associated figures:

They show: Fig. 1 the side view of a pair of tools,

designed as a rack, which is in a work machine shown schematically is built in;

Fig. 2 the side view with group division of the bottom part of the toothed tool according to Fig. 1;

Fig. 3 is a partial view of a toothed workpiece made according to the present invention generated by compression deformation;

Fig. 4 is a diagrammatically shown, enlarged Side view of the sequence of teeth according to increasing radii;

Fig. 5 is an elevation of the left end of the tool shown in Fig. 2 and

Lawyers KRIEGER · ROTHF · PINDHP

0.1, Hans Krieger

Dr. jur. H. Jochen Krieger

Dr. jur. A. Reinhard Rothe Dr. jur. Wolfgang Pinder

, 000 D0s3el * rt 1

HOStracn OBUtJ

Dresdner Bank, D'dorf No. 2521404 Kreissparkasse D'dorf No. 1039725 Postal check: Essen No. 3572-431

- 5 -

. ^ Fig. 6 is a partial plan view of that shown in Fig. 2 / - tool shown.

A preferred embodiment of the invention is described below with reference to Figures 1, 2, 4, 5 and 6 described. It is the construction of a pair of identically designed and identically toothed tools (10A) and (10B), which are suitable for the production of the above-mentioned tooth profiles on the circumference of cylindrical workpieces are.

A working machine that is likewise suitable for this and can accommodate the tools according to the invention is already included in FIG mentioned USPS 2,995,964. Of course, other types of machines can also be used, provided they are suitable Find use.

As shown in Fig. 1, there is a workpiece (12) between the lower and upper tools (10A) and (10B). According to Fig. 1 there are tools (10A) and (10B) at the beginning of an operation for the formation of tooth elements on the circumference of the workpiece (12). This can of course be held by suitable, not shown, support devices, provided that the engagement of the Pressure tools (10A) and (10B) necessary rotation of the tool is not hindered. Incidentally, the part tools are (10A) and (10B) identical and as similar racks on opposite working surfaces of the Machine shown. The teeth of the tools are in engagement with the cylindrical circumference of the workpiece.

Lawyers KRIEGEP-ROTHE-PINDfR

Dr. jur. Hans Krieger <000 Düsseldorf 1 Telex: 0858/7428 ttkr

Dr. jur. H. Jochen Krieger '"* ^abe ' ^{: Jur} _n ^{k D} " ^Ds ! ^E i ^d ° ^rf _{M) B1} "

n _n " _t f..L Rono Dresdner Bank, D there No. 2521404

Dr. Jur.A. Reinhard Rothe P.O. Box 6808 Kreissparkasse D'dorf No.! 03972S

Dr. jur. Wolfgang Pinder postal check: Essen No. 3572-431

2A24033

The printing or partial tools are made by corresponding devices (10A) and (10B) movable in the longitudinal direction and slide, as shown, along predetermined paths (14) and (16) which are incorporated in the guide bed (18) and in the sliding head (20) of the working machine. Also move the tools (10A) and (10B) in opposite directions. A pair of identical pressure cylinders (22) and (24) with pistons (34) and (36) and connecting rods are used for this purpose (38) and (4o). The connecting rod (38) stands with the rear end of the tool (10A) and the shaft or connecting rod (40) with the rear end of the tool (10B) in communication. Suitable valve and control devices (not shown) can cooperate with the cylinders (22) and (24) in order to synchronize their action, thereby increasing move the tools (10A) and (10B) simultaneously and at the same speed in opposite directions.

Of course, instead of the one shown here Printing cylinder, other suitable movement elements can also be used.

The effect of the device can be seen from the above. In the illustrated position of workpiece (12) and tools (10A) and (10B) the pressure cylinders work synchronously in such a way that the tools work simultaneously and at the same speed be guided past the workpiece.

Since the distance between the work surfaces (42) and (44) is less than the diameter of the workpiece (12), become the profiles of surfaces (42) and (44), i.e. so

Lawyers KRIEGEP · ROTHE · PINDER ^ ;; J * ³²

Dr. jur. Hans Krieger _<0 00 Düsseldorf 1

Dr. jur. H. Jochen Krieger _o ^ A, «" .n /

' ^a D ^ ti ^ u car \ a Dresdner Bank, D dorf No. 2521404

Dr. jur. A. Reinhard Rothe PO Box 6808 _{Krelssparkasse D. village no} . _1039725

Dr. jur. Wolfgang Pi nder postal check: Essen No. 3572-431

the tooth elements of the tools, in the scope of the workpiece embossed or impressed.

The end of a work cycle is reached as soon as the ends (46) and (48) of the tools over the workpiece (12) slide out. The workpiece can now be removed. At the same time, the tools (10A) and (10B) are returned to their starting positions - as shown in Fig. 1, Λ so that the leading ends (50) and (52) again in the amount of Workpiece. At the same time, a new workpiece can also be inserted and the workflow can begin again.

During the penetration of the tool teeth into the surface of the workpiece, the workpiece material, normally normal steel, flows radially along the surface and tangential direction, so that grooves or grooves with a smaller diameter than the original of the workpiece, as well as elevations with a larger diameter than that of the original workpiece arise. This "Flow" must of course be taken into account when considering the initial diameter of the tool will; so that the required accuracy of the final tool is achieved.

An example of this is shown in Fig. 3, in which a portion of the cross-section of a gear in the finished state is shown. Since there is no material in cold compression forming is removed, the original diameter of the workpiece cannot be determined by the final outer diameter, still be defined by the diameter at the tooth root.

Lawyers KRIEGER · ROTHF · ΡΙΝΟΓΡ

Dr. jur. Hans Krieger

Dr. jur. H. Jochen Krieger Dr. Jur. A. Reinhard Rothe Dr. jur. Wolfgang Pi nder

/ jnnn Πι "<! <! ρΙΗτ + 1

P.O. Box 6808

Telex: 0858 / 7428ttkr

Cable: Ju * DweMotf Dresdner Bank, D dorf No. 2521404 Kreiseparkasse D'dorf No. 1039725 Postal check: Essen No. 3572-431

Therefore, the rolling diameter (D ₁ ) of the workpiece is chosen so that the area (56) of removed material below the D ₁ periphery is equal to the area (58) of material on a larger diameter than (D ₁ ). The diameter (D ₁ ) practically marks the division line for tooth tools such as (10A) and (10B).

The pressure angle or the incline of certain teeth of the tools (10A) and (10B) is determined by the cos 0 / D ₁ , multiplied by the cos of the pressure angle at the pitch circle diameter of the tooth element (54), where D stands for the tex circle diameter of the workpiece. This means that the basic divisions of the tool and workpiece are identical. The linear pitch of the teeth on the tool, measured on the pitch line, corresponds to the circular pitch of the teeth on the workpiece, measured on a circle with the diameter (D ₁ ). At least some tooth elements on the tools (10A) and (10B) must therefore have the overall depth of the tooth profiles of the workpiece, that is to say be identical to the teeth to be formed on the workpiece.

Since the tools (10A) and (10B) are separate, they must be at a point near the sliding ends form a gap between the working surfaces (42) and (44) which is equal to the diameter of the Tooth root of the workpiece (12) minus a few thousandths of a cm for buffering changes in elasticity and the compression of any oil films through the rolling pressure.

Lawyers KRIEGEP-.ROTHF. · PINDFR

Dr. jur. Hans Krieger <000 Düsseldorf 1 ™ ^e * ^{: 0858} J ⁷ < ²⁸ «* ^r . ^ / ^ "· '

Dr. jur. H. Jochen Krieger ^ Ίΐ ^ ,,, '

_._ ,, _ D / -. Otf "o ^ Ki ΚΟΠΗ Dresdner Bank, D dorf Nr, 2521404

Dr. jur. A. Reinhard Rothe P.O. Box 6808 Kreissparkasse D'dorf No. 1039725

Dr. jur. Wolfgang Pi nder postal check: Essen No. 3572-431

In practice, the tool or tool pair is preferably passed over the workpiece only once, i.e. it is only one work step necessary.

The distance between the work surfaces (42) and (44) from each other is variable, so that the depth of the indentations on the Workpiece gradually increases as machining progresses.

The work surfaces approach with increasing work flow or increasing distance of the tools (1OA) and (10B). This "approach" can be viewed as the advance of the tools into the workpiece when the Move tools relative to the workpiece.

As can be seen from the figures, the convergence the mutual approach of the tools through a gradual increase in tooth heights in successive Tooth groups caused while the division line remains constant.

In Figures 2,4,5 and 6, the (lower) bottom tool (1QA) is explained according to the present invention, wherein the upper tool. (10B) xäjc constructed in exactly the identical way ..

With (60) qine "theoretical reference line is shown, which can be thought of as the upper limit of all teeth. With parallel sliding or guide ways (14) and (.16) in the working machine must also include the theoretical Reference line (60) can be thought of as parallel to these paths, so that when the tips of the tool teeth are on the line

Lawyers KRIEGER · ROTHF · PINDfTP

Dr. jur. Hans Krieger

Dr. jur. H. Jochen Krieger

Dr. jur. A. Reinhard Rothe Dr. jur. Wolfgang Pinder

₄₀ 00 Düsseldorf 1

.... P.O. Box 6808

JeIe * ff ™ ⁸ «*. '

Cable: Jurk Dus ^ orf. _ Dresdner Bank, D there No. 2521404 Kreissparkasse D'dorf No. 1 039725 Postal check: Essen No. 3572-431

- 10 -

(60) run, no change in the distance between the surfaces (42) and (44) can take place when the tools move along paths (14) and (16).

With (62) in the following the teeth of the Tool (10A) referred to. You are in the present case divided into seven groups (Fig. 2), indicated by vertical boundary lines (64), (66), (68), (70), (72) and (74) so as are separated from each other by the guide or sliding ends. It can be seen especially from Fig. 4 that the dividing line (76) of the tool teeth (62) parallel to the reference line (60) up to approximately the boundary line (64) runs. From then on it decays downwards and this decay increases until the sliding end (46) of the tool is reached. In the direction of the leading end (50) - see Figs. 2 and 4 - the dividing line (76) remains parallel to the reference line (60), on the other hand it decreases from tooth group to tooth group in the direction of the leading end (50) the distance between the tips of the teeth and the reference line (60).

As already stated earlier and as also from the US-PS 3 o15 243 is known, corresponds to the shape and size of the teeth (62A) between the boundary lines (64) and (66) the exact shape and size of the teeth to be formed on the workpiece. This also applies to the teeth (62B) between the perimeter line (64) and the sliding end (46), although the division line of the teeth (62B) is down from the Reference line (60) leads away.

As a result, seam lines or other imperfections, which at the end of an operation due to the reduced

Lawyers KRIEGEP · ROTHE- PINDFR τ ^ η ^Α ΐΐ "οι ³²

Dr. jur. Hans Krieger <000 Düsoeldcrf 1

Dr. jur. H. Jochen Krieger '' . ,,; Cable: Jurk ^DOs ~ ' ^d ° ^rf "■,

'. _; ,, _, D ^ ofio / ^ l ·. RCtna Dresdner Bank, Dorf Nr. 2521404

Dr. Jur.A. Reinhard Rothe P.O. Box 6808 Kre.ssparkasse D'dorf No. 1039725

. Dr. jur. Wolfgang Pinder Postscheck: Essen No. 3572-431: ..

- 11 contact surface can be formed, avoided.

The total depth of the teeth (62A) between the boundary lines (64) and (66) is preferably equal to that of the teeth to be formed on the workpiece.

Between the leading end (50) of the tool and the boundary line (74) there are sharp-edged, pointed teeth (62C) which serve to grasp the workpiece and its rotation during machining. The distance between the tooth tips of these teeth (62C), ie the lower and upper tool parts, is slightly smaller than the pitch diameter (D ₁ ) of the workpiece and differs from (D ₁ ) of the workpiece by a few thousandths of a cm.

The linear pitch of the teeth (62C) corresponds to that of all other teeth on the tool racks. The number of the teeth (62C) is preferably half the number of teeth on the entire workpiece, or a tool < part (1OA). If the latter has e.g. 20 teeth along its entire length, there are also between the boundary line (74) and the leading end (50) another 10 teeth (62C).

The reference line (60) touches all fully formed teeth of group (62A), while those to (60) are parallel running line (78) touches the roots of teeth (62A).

The tips or upper boundaries of the tool teeth (62D) are between the boundary lines (66) and (68)

Lawyers KRIEGEP · ROTHE · PINDfR

Dr. jur. Hans Krieger / fjOO Düsoeldcrf 1 Telex: 0858/7428 ttkr

Dr. jur. H. Jochen Krieger '! < ^Abe l ^{: Jur} _D ^{k 0} ^ ¹ ? ⁰ * _{oc M}

' ^a η jf-L cofiQ Dresdner Bank, D dorf No. 2 521

Dr. jur. A. Reinhard Rothe P.O. Box 6808 Kreissparkasse D'dorf No. 1039725

Dr. jur. Wolfgang Pinder, postal check: Essen No. 3572-431

-12 -

tapered or abraded so that the tips of (62D) are below the tips of the fully formed teeth (62A) run. The edges of the teeth (62D) are also slightly weakened, so that the tooth thickness, measured on the parting line, is slightly less than the thickness of the fully formed teeth (62A).

The teeth (62A) have a radius (80A) of 0.046 cm at their upper edges, for example. Accordingly, the Teeth (62D) have a radius (80D) of 0.058 cm, which is thus larger than that of the teeth (62A).

As Fig. 4 in particular shows, the tooth roots are also correspondingly deformed, so that the teeth (62D) are modified have opposite the teeth (62A). For example, is the thickness of the teeth (62A) at the division line 0.183 cm, the thickness of the teeth (62D) at the same point is 0.173 cm. Is the height of the tool teeth (62A) - measured over everything - at 0.211 cm, the total height is of the teeth (62D) only 0.195 cm.

The tips and roots of the teeth within groups (62E), (62F) and (62G) between the boundary lines (68), (70), (72) and (74) are described by radii, the radius (80F) of the teeth (62F) being larger is than the radius (80E) of the teeth (62E), the radius (82F) of the teeth (62F) is larger than the radius (82E) of the teeth (62E), the radius (80G) at the tips of the teeth (62G) is larger than the radius (80F) at the Tips of the teeth (62F) and the radius (82G) of the roots of the teeth (62G) is greater than the radius (82F) of the Tooth roots of (62F).

Lawyers KRIEGER · ROTHE · PINQFR * ^ü , ^ro ; ^A t, ^a ^ ^e ™ ³²

". - Telephone: (0211) 320501

Dr. jur. Hans Krieger <000 Düsseldorf 1 Telex: 0858/7428 ttkr

Dr. jur. H. Jochen Krieger '' Cable: Jurk Düsseldorf

_. . . a D L j η L 'Dnotfar> h RfifiA Dresdner Bank, D'dorf No. 2521404

Dr. jur. A. Re.nhard Rothe PO Box 6808 Kreissparkasse D'dorf No. 1039725

Dr. jur. Wolfgang Pi nder postal check: Essen No. 3572-431

For example, if the tip weakening of the teeth (62E) has a value of 0.091 cm for the radius (80E) ₁ , the root weakening of the teeth (62E) has a radius of 0.096 cm. .

As can also be seen from Fig. 4, the upper edges of the teeth are located of the group (62E) below the tooth edges or

Tips of teeth (62D). The same applies to the ^

Teeth (62F) / (62E), and (62G) / (62F). At the same time, the root boundaries of the teeth run (62D)> (62E), (62F) and (62G) to those of the preceding groups to the fully formed teeth of Group (6.2A). The same consideration and construction This also applies to the tooth thicknesses, starting with group (62G) up to the fully developed teeth of group (62A). On the other hand, the distance between the teeth of successive groups progressively decrease in the same direction. '

In summary, the attenuations of the tooth tips (upper edges) of the tool teeth (62G), (62F) and (62E))

defined by radii that progressively begin with the teeth of the group (62G), up to the teeth of the Remove group (62A). This applies in the same direction to the root weakening of each subsequent group. At the same time, the baselines of the teeth become progressive decreased while the apex lines rise accordingly.

In any case, the sharp-edged teeth grip first of the group (62C) into the tool. The tooth groups (62G), (62F) and (62E) follow one after the other, which the create the first, still weak profiles on the workpiece.

Lawyers - KRIFGER ROTHF PIND (IR

Dr. jur! Hans Krieger 1000 Di ^ seH-rfi Telex: 0858/7428 ttkr

Dr. jur. H. Jochen Krieger "" ~ £ ^abe ' ^{: Jur} _R ^{k 0} ^ ⁰ *, "^

' ^a Dn ^ tfnAU RQnQ Dresdner Bank, D dorf No. 2521404

Dr. jur. A. Reinhard Rothe P.O. Box 6808 Kreissparkasse D'dorf No. 1 039725

Dr. jur. Wolfgang Pinder postal check: Essen No. 3572-431

- 14 -

These are then profiled up through the teeth (62D) to an involute configuration until the final shape is finally formed on the workpiece by the teeth (62A) will.

Of course, there are transitions (84) between the individual groups of teeth that provide a smooth continuation allow.

In order to avoid undercuts on the tool, one or both upper edges (see Fig. 5) can be broken with an edge be provided. A radius is also suitable for this. The tool teeth are used for the formation of mandrel teeth e.g. (Fig. 6) (62A) held perpendicular to the tool surfaces. If, on the other hand, worm threads and the like are to be formed, then so the tool teeth are inclined to the sides or in the direction of movement.

Claims (1)

Lawyers KRIEGEP · ROTHE · PINDFR Dr. jur. Hans Krieger <000 Du33eldorf 1 Telex: 0858/7428 ttkr Dr. jur. H. Jochen Krieger '"* ^abe ' ^{: Jurk D ,. Üs} *; ' ^village _kl " _ /. ".,, _, D ^ etf ^ h Rons Dresdner Bank, D'dorf No. 2521404 Dr. jur. A. Reinhard Rothe HOSttaCh bbUÖ Kreissparkasse D'dorf No. 1039725 Dr. jur. Wolfgang Pinder: Postal check: Essen No. 3572-431 242-033 - 15 - P a t e nt a ns ρ rü cn e Tool for the production of tooth elements on the circumference of a cylindrical workpiece by pressure deformation, consisting of the actual tool body with guide and sliding ends and a work surface that has a large number of tooth profiles, which is characterized by a first group of tooth profiles between the leading end and the sliding end, and each tooth element in this first group has a profile that corresponds to the profile of the teeth to be formed on the workpiece, and that a second group of tooth elements is arranged between the leading end of the tool and the first group of tooth elements where the tips and roots of the teeth of the second group are defined by radii. Tool according to Claim 1, characterized in that third and fourth groups of tooth elements (62E), (62F) and (62G) are arranged between the leading end (50) and the second group of tooth elements (62D), the tooth roots and tips of which are defined by the radii (80E) , (80F), (80G), (80E), (82F) and (82G) are defined, the radius (80E) of the tooth tips of the third group being greater than the radius (80D) of the tooth tips of the second group and the radius (80F) of the tooth tips of the fourth group (62F) is larger than the radius (80E) of the tooth tips of the third group (62E). Lawyers KRIEGER · ROTHF- PINDEP * Z ₀ Tm »^ * Dr. Jur.Hans Krieger 1000Du = SeMTfI Tele * 0858/7428 ttkr Dr. jur. H. Jochen Krieger "" * "'£ ^{ab #} ' ^{: Ju} * ⁰ ^ ⁰ * '^ - D ^ itfonli καηα Dresdner Bank, Dorf No. 2521404 Dr. jur. A. Reinhard Rothe P.O. Box 6808 Kre.s.park.sse Ddorf No. 1039725 Dr. jur. Wolfgang Pinder postal check: Essen No. 3572-431 - 16 - 3. Tool according to claim 2, characterized in that the radius (82E) of the roots of the teeth of the third group (62E) is greater than the radius (82D) of the tooth roots of the second group (62D) and the radius (82F) of the tooth roots of the fourth group (62F) is larger than the radius (82E) of the tooth roots of the third group (62E). 4. Tool according to claims 2 or 3, characterized in that the tips of the teeth of the second group (62D) are below the tips of the teeth of the first group (62A) that the tips of the teeth of the third group (62E) below Tooth tips of the teeth of the second group (62D) and the tooth tips of the teeth of the fourth group (62F) are below the tooth tips of the teeth of the third group (62E). 5. Tool according to claims 2, 3 or 4, characterized in that the root line of the teeth of the second group (62D) above the root line of the teeth from the first group, the root line of the teeth of the third group (62E) above the root line of the Teeth of the second group (62D) and the root line of the teeth of the fourth group (62F) is above the root line of the teeth of the third group. 6. A tool according to any one of claims 1 to 5, characterized labeled in ze ichnet that a tooth group (62C) is arranged at the leading end (50) with tooth tips which expire sharp. Lawyers KRIEGER · ROTHE -PINDFP Dr. jur. Hans Krieger \; \. "4000 Düsseldorf Γ Dr. jur. H. Jochen Krieger ^ ΐΐ ^ Ι, _raJ ™ ■ _. '_,. r,, D ^ ofio ^ K ROnQ Dresdner Bank, D'dorf No. 2521404 Dr. Jur.A. Reinhard Rothe P.O. Box 6808 Kreissparkasse D'dorf No. 1039725 V Dr. jur. Wolfgang Pinder postal check: Essen No. 3572-431 - 17 - 7. Tool according to claim 6, characterized in that that the tooth tips of the teeth of the second group (62D) are below the tooth tips of the first group (62A) and the tooth tips of the teeth of the group (62C) are below those of the second group (62D). 8. A tool according to claims 6 or 7, characterized in that the root line of the teeth of the second group (62D) above the root line of the teeth of the first group (62A) and the root line of the teeth of the group (62C) above the root line of the Teeth of the second group (62D) runs. 9. A tool according to claim ^1, characterized in / that the average thickness of the teeth, measured at the pitch line, continuously decreasing from tooth to tooth, starting with the teeth in the first group in the direction of the leading end of the tool. 10. Tool according to one of the preceding claims, characterized in that all the teeth of the groups (62A), (62C) to (62G) have a common division line. 11. Tool according to one of the preceding claims, characterized in that the distance between the individual teeth of successive groups, measured on the Te; llungslinien, continuously decreases, starting with the teeth of the fourth group in the direction of the teeth of the first group. Lawyers Dr. jur. Hans Krieger Dr. jur. H. Jochen Krieger Dr. jur. A. Reinhard Rothe Dr. jur. Wolfgang Pinder WARRIOR ROTHE PINDRP 1000 Düsseldcrt post box 6808 Office: Alexanderstraße 32 Telephone: (0211) 320501 Telex: 08S8 / 7428 ttkr Cable: Jurk Düsseldorf Dresdner Bank, D'dorf No. 2521404 Kreissparkasse D'dorf No. 1039725 Postal check: Essen No. 3572-431 - 18 - 12. Tool according to one of the preceding claims, characterized in that the linear division of all teeth in all groups is constant.