DE2240951B1

DE2240951B1 - WHEEL CUTTER

Info

Publication number: DE2240951B1
Application number: DE19722240951
Authority: DE
Inventors: Franz; Reuß Georg; 5600 Wuppertal Koch
Original assignee: Hermann Leimbach KG, 5600 Wuppertal-Barmen
Priority date: 1972-08-19
Filing date: 1972-08-19
Publication date: 1974-02-07
Also published as: DE2240951A1; DE2240951C2

Description

Die Zahnflanken kommen also nicht mit dem Zahn des Rades in Berührung, infolgedessen schnei- The tooth flanks do not come into contact with the tooth of the wheel, as a result,

den sie auch nicht. Das wird dadurch erreicht, daß der zuerst anschneidende Zahn des Vorfräsers im Einlauf des Rades eine breite Kopfschneide hat. Die Breite dieser Kopfschneide entspricht angenähert der Lückenbreite am Außendurchmesser des Rades. Die weiteren Zähne des Fräsers in Richtung Maschinenmitte dringen zunehmend tiefer in das Rad ein.she doesn't either. This is achieved by cutting the first Tooth of the roughing cutter has a wide cutting edge in the run-in of the wheel. The width this cutting edge corresponds approximately to the width of the gap on the outer diameter of the Wheel. The other teeth of the milling cutter increasingly penetrate towards the center of the machine deeper into the wheel.

Wenn dabei die Zahnbreiten in Eingriffsrichtung stetig abnehmen, bewirkt die geringer werdende Kopfschneidenbreite eine der Zahnlückenweite im Grunde des Rades entsprechende Kontur. Da die Zähne im Verlauf des Eingriffs schmaler werden, berühren die Fräserzahnflanken niemals das Rad. Die einzelnen Zahnkopfschneiden arbeiten ähnlich wie ein Nutenfräser bzw. wie eine Nutenräumnadel lediglich am Außenumfang.When the tooth widths steadily decrease in the direction of engagement, this causes the decreasing cutting edge width is basically one of the tooth gap widths Corresponding contour of the wheel. As the teeth become narrower in the course of the procedure, the cutter tooth flanks never touch the wheel. The individual tooth tip cutting edges similar to a slot milling cutter or a slot broach only work on the outer circumference.

Weiterhin wird als vorteilhaft angesehen, wenn der Vorfräser eine wesentlich geringere Spannutentiefe aufweist als der Grundfräser. Da die Flanken der Vorfräserzähne bis auf das herstellende Drehen unbearbeitete sind und keine Flankenschneiden existieren, ist auch eine den Verhältnissen der fertigen Verzahnung angepaßte Spannutentiefe nicht mehr erforderlich. Dadurch wird erreicht, daß die zu bearbeitenden Flächen der Zahnbrüste des neuen Vorfräsers auf ein Minimum beschränkt werden können, wodurch ebenfalls der Herstellungs- und I(ostenaufwand gemindert ist. It is also considered to be advantageous if the roughing cutter has a has a much smaller flute depth than the basic cutter. Because the flanks the milling cutter teeth are unmachined except for the manufacturing turning and none Flank edges exist, is also one of the conditions of the finished toothing adjusted flute depth no longer required. This ensures that the Areas to be machined on the toothbrushes of the new roughing cutter are limited to a minimum can be, which also reduces the manufacturing and I (ost expenditure is.

Wenn die Anzahl der Zähne des Vorfräsers pro Schraubengang die Anzahl der Zähne des Grundfra sers pro Schraubengang übersteigt, so ist damit in vorteilhafter Weise erreicht, daß nicht jeweils ein Zahn des Vorfräsers und ein Zahn des Grundfräsers zugleich in Eingriff kommen, was eine Steigerung der Laufruhe des gesamten Wälzfräsers zur Folge hat. If the number of teeth of the roughing cutter per screw thread is the number the teeth of the Grundfra sers exceeds per screw thread, so it is more advantageous Way achieved that not one tooth of the roughing cutter and one tooth of the basic cutter come into engagement at the same time, which increases the smoothness of the entire hob has the consequence.

Infolge der bereits geschilderten Maßnahme, eine sehr geringe Spannutentiefe vorzusehen, kann die Zähnezahl des Vorfräsers gegenüber der entsprechenden Zähnezahl des Grundfräsers - bei gleicher nutzbarer Zahnlänge - sogar verdoppelt werden, wodurch die Schnittleistung des Vorfräsers gegenüber bisher bekannten Vorfräsern beträchtlich gesteigert ist. As a result of the measure already described, a very small flute depth can be provided, the number of teeth of the milling cutter compared to the corresponding number of teeth of the basic milling cutter - with the same usable tooth length - can even be doubled, which means the cutting performance of the roughing cutter is considerable compared to previously known roughing cutters is increased.

Und nicht zuletzt ist es im Rahmen der Erfindung von Bedeutung, wenn der Vorfräser im Bereich seiner axialen Aufnahmebohrung ein Vielnutprofil aufweist. Damit kann der Vorfräser nunmehr in ver- schiedenen Drehwinkellagen bezüglich des nachgeschalteten Grundfräsers ausgerichtet werden. Hiermit und mit Hilfe von verschieden breiten Distanzbuchsen wird eine Feinverstellbarkeit erwirkt, die eine Anpassung jeder Radgröße und jeden Radschrägungswinkel ideal im Sinne der optimalen Zerspanungsaufteilung mit gesteigerter Laufruhe erlaubt. And last but not least, it is important in the context of the invention if the pre-milling cutter has a multi-groove profile in the area of its axial receiving bore. This means that the milling cutter can now be used in different different angles of rotation with respect to the downstream basic milling cutter. With this and with the help of various wide spacer sleeves, a fine adjustability is achieved that an adjustment Every wheel size and every wheel helix angle is ideal in terms of optimal cutting distribution allowed with increased smoothness.

Es ist der Erfindung gelungen, einen Wälzfräser zu schaffen, der sich insbesondere durch eine leichte und wohlfeile Herstellbarkeit seines Vorfräsers auszeichnet und dessen Grundfräser vermittels seiner durch den die Hauptzerspanungsarbeit leistenden Vorfräser geschont wird. wodurch eine Standzeitverlängerung erzielt ist. The invention has succeeded in creating a hob that in particular by the easy and inexpensive manufacturability of its roughing cutter and its basic milling cutter by means of its through the main cutting work performing rough milling cutter is spared. whereby an extension of the service life is achieved.

Die Erfindung wird nachstehend an Hand eines Ausführungsbeispiels beschrieben. Es zeigt die Zeichnung den neuen Wälzfräser in einer Achsschnittdarstellung: Auf einer Werkzeugspindel 10 sind hintereinander und mittels einer Distanzbuchse 11 im Abstand voneinander ein Vorfräser 12 und ein Grundfräser 13 angeordnet. Während der Grundfräser 13 als üblicher Hochgenauigkeitsfräser ausgeführt ist mit vollständig durch Schleifen und Hinterschleifen bearbeiteten Zähnen 14, die sowohl Kopfschneiden 15 als auch Flankenschneiden 16 aufweisen, ist der Vorfräser 12 wesentlich einfacher gestaltet. The invention is described below using an exemplary embodiment described. The drawing shows the new hob in an axial section: On a tool spindle 10 are one behind the other and by means of a spacer sleeve 11 a pre-milling cutter 12 and a basic milling cutter 13 are arranged at a distance from one another. While the basic milling cutter 13 is designed as a conventional high-precision milling cutter with complete teeth 14 machined by grinding and relief grinding, which are both head cutting edges 15 and flank cutting edges 16, the roughing cutter 12 is much simpler designed.

Die Zähne 17, 18, 19 des Vorfräsers 12 weisen lediglich kopfseitige Schneidkanten 20 auf. während ihre bis auf den Herstellungsvorgang des Drehens unbearbeiteten Flanken 21 etwa senkrecht abfallen. The teeth 17, 18, 19 of the rough milling cutter 12 only point on the head side Cutting edges 20 on. while their raw up to the manufacturing process of turning Flanks 21 drop approximately vertically.

Die Zahndicken 22. 23, 24 des Vorfräsers 12 nehmen zum Ende des Vorfräsers hin ab, und zwar im dargestellten Beispiel kontinuierlich von Zahn zu Zahn entlang der Spiralwindung. The tooth thicknesses 22, 23, 24 of the roughing cutter 12 take the end of the roughing cutter down, and in the example shown continuously along from tooth to tooth the spiral turn.

Wie ferner aus der Zeichnung ersichtlich, ist die Spannutentiefe 25 des Vorfräsers 12 wesentlich geringer als die Spannutentiefe 26 des Grundfräsers 13. As can also be seen from the drawing, the flute depth is 25 of the roughing cutter 12 is much smaller than the flute depth 26 of the basic cutter 13th

Infolgedessen ist es möglich, daß - bei gleicher nutzbarer Zahnlänge - der Vorfräser über wesentlich mehr Zähne pro Schraubengang verfügt als der Grundfräser.As a result, it is possible that - with the same usable tooth length - the pre-milling cutter has significantly more teeth per screw thread than the basic milling cutter.

Im Bereiche seiner - nicht dargestellten - axialen Aufnahmebohrung weist der Vorfräser 12 ein Vielnutprofil zu seiner Befestigung mittels einer Paßfeder auf der Werkzeugspindel 10 auf, welches ihm eine in Umfangsrichtung positionsveränderbare Anordnung auf der Werkzeugspindel gestattet. In the area of its - not shown - axial receiving bore the roughing cutter 12 has a multi-groove profile for its attachment by means of a feather key on the tool spindle 10, which has a variable position in the circumferential direction Arrangement on the tool spindle permitted.

Claims

Claims: 1. Worm-shaped hob for gears with involute profile, which consists of a pre-milling cutter and a basic milling cutter, the are arranged at a distance from each other on a common tool mandrel and at where only the basic milling cutter has the profile of the reference rack, characterized in that that the teeth (17, 18, 19) of the roughing cutter (12) have an approximately rectangular cross-section have approximately right-angled tooth flanks (21) to the longitudinal axis of the cutter and only in the head area Have cutting edges (20).

2. Hob according to claim, characterized in that the tooth thicknesses Remove (22, 23, 24) of the roughing cutter (12) towards the end of the roughing cutter (12).

3. Hob according to claim 1 and 2, characterized in that the roughing cutter (12) has a much smaller flute depth (25) than the Basic cutter (13).

4. Hob according to claim 1 to 3, characterized in that the number of teeth of the pre-milling cutter (12) per screw thread the number of teeth of the basic milling cutter (13) per screw thread.

5. Hob according to claim 1 to 4, characterized in that the pre-milling cutter (12) has a multi-groove profile in the area of its axial receiving bore.

The invention relates to a worm-shaped hob for gears with involute profile, which consists of a pre-milling cutter and a basic milling cutter, the are arranged at a distance from each other on a common tool mandrel and at where only the basic cutter has the profile of the reference rack.

With this generic term, the invention takes on a state of the art Reference, as he said in the magazine "Metalworking Production", issue from November 9th.

1960, pp. 85 and 86. There is the snail-shaped one Hob formed from a pre-milling cutter and a basic milling cutter, one behind the other a common spindle and arranged for example by means of spacer sleeves from each other can be separated. The separation of the hob into the two individual cutters has the sense of integrating the tool life into one piece by connecting the pre-milling cutter To increase milling cutters and to make the individual milling cutters independently interchangeable, whereby the tool costs are reduced overall.

The disadvantage, however, is that the roughing cutter as well as the basic or High-precision milling cutters each completely machined for themselves, d. H. with back turned and relief-ground tooth flanks represent tools, with only the pre-milling cutter lacks the high-precision contour required to produce the involute.

Therefore, the invention is based on the object in the sense of known problem to go one step further, that is, one Hobs of the type mentioned, which is characterized by an even higher overall performance and a further improved service life extension of the basic milling cutter on the one hand and in particular On the other hand, it is characterized by a structurally particularly simple design of the roughing cutter.

According to the invention this object is achieved in that the teeth of the Rough cutter approximately rectangular cross-section with approximately right-angled to the cutter longitudinal axis Have tooth flanks and only have cutting edges in the head area.

The effect of the measure thus claimed is that the Rough milling cutter, in contrast to the previously known type, only has cutting edges on the head side having. Its flanks themselves do not form any cutting edges, so that the machining work only falls to the cutting edges of the tooth tips. This has significant advantages in that than now only the tooth backs of these cutting edges need to be back-worked. In addition, the roughing cutter can only be machined by turning. It fall hence the time-consuming and costly finishing operations of relief grinding the head and flank cutting continued. The new roughing cutter only needs in the soft, to be undercut at the head cutting edges in the unhardened state. Thus is a supreme Hobs that can be produced cheaply are achieved.

The teeth of the milling cutter thus work from the full material of the To be toothed spur gear by means of their head cutting the tooth gaps of the spur gear in rough outline, while the teeth of the basic or high-precision milling cutter only the fine machining is done, so that the expensive high-precision milling cutter considerably spared and its service life is increased dramatically. In practice are machining ratios of around 80/20 to 90/10 without any difficulty (Pre-milling cutter / basic milling cutter) achievable.

Another advantage that results from the fact that the teeth of the roughing cutter only have to be ground on their tooth face, it can be seen that significantly higher alloyed for the material of the milling cutter - and therefore highly wear-resistant - Steels can be used, which was previously related to the economic limits the grinding process required in known milling cutters has failed.

With the new hob it is possible to use the roughing cutter with every any - only matching in the sizes of the gear geometry - Combine high-precision milling cutters, thereby reducing existing basic milling cutters can still be advantageously supplemented subsequently.

In terms of machining technology, it is also advantageous if decrease the tooth thickness of the roughing cutter towards the end of the roughing cutter. This measure allows the closest possible approximation of the cutting edges of the milling cutter teeth worked out profile to the final involute profile, because with increasing The teeth of the milling cutter become thinner, i. i.e., they take in the circumferential direction of the spur gear, as the depth of engagement increases, less material is removed, as a result of which an approximately wedge-shaped, but approximated by the rolling process of the involute rounded tooth gap is achieved during the pre-milling stage.