WO2006053854A1

WO2006053854A1 - Device and method for providing workpieces with a toothing, particularly with a toothing on the face

Info

Publication number: WO2006053854A1
Application number: PCT/EP2005/055900
Authority: WO
Inventors: Martin Strauch; Wolfgang Heinemann
Original assignee: Profilator Gmbh & Co. Kg
Priority date: 2004-11-20
Filing date: 2005-11-11
Publication date: 2006-05-26
Also published as: EP1817131A1; DE102004056171A1

Abstract

The invention relates to a device for providing workpieces (1, 1', 1'', 1''') with a toothing, comprising a tool spindle and a workpiece spindle, which are rotationally driven in relation to one another with a fixed rotational speed ratio and whose axes (2, 4) have a distance between axes (R). The tool spindle supports at least one cutter head (3), which is equipped with a cutting tool (5), can be advanced toward the workpiece (1, 1', 1'', 1''') and which can be continuously displaced in an advancing direction (V) during the metal-cutting machining of the workpiece (1, 1', 1'', 1'''). The advancing device (V) has a radial component extending in the axial distance direction (R). In order to produce toothings on the face, the invention provides that the tool spindle axis (4) can pivot about a tilt axis (12) extending essentially parallel to the workpiece spindle axis (2) so that its angle of tilt (f) about this axis (12) changes while being accompanied by the change in the distance between axes (R).

Description

Device and method for the toothing of workpieces, in particular with a spur toothing

The invention relates to a device for toothing workpieces with a tool spindle and a workpiece spindle, which are rotationally driven in a fixed rotational speed ratio and whose axes have a center distance, wherein the tool spindle carries at least one cutter head which has a cutting tool and which bears on the tool head Workpiece is deliverable and during the machining of the workpiece in a feed direction is continuously displaceable, wherein the feed direction has a running in the Achsab- direction radial component.

The invention further relates to a method for cutting workpieces having the features:

a workpiece to be toothed is rotationally driven by a workpiece spindle about a workpiece spindle axis;

a cutter head having at least one beater blade is rotationally driven by a tool spindle about a tool spindle axis;

- The tool spindle and the workpiece spindle run in a fixed speed ratio to each other;

- The tool spindle axis and the workpiece spindle axis have an axial distance from each other;

- The feed has a radial component in the direction of the axial distance.

DE 10227423 A1 describes a method and a device for producing front-side coupling teeth. There, negative receiving surfaces are created by the tool spindle axis in front of the head of the workpiece within an imaginary axial extension of the Werk¬ piece outline contour.

A device and a method are known from DE 2650 955 C1, in which a beater knife carried by a knife head dips into a rotating workpiece. The tool spindle axis can be adjusted about an inclination axis to influence the cross-sectional profile of the groove produced. The feed takes place here parallel to the extension direction of the workpiece axis.

The invention has the object of developing the generic method or the generic device to the effect that even teeth with flank profiles, which have a component in the radial direction, get tooth flanks, which run essentially flat.

The object is achieved by the invention specified in the claims, wherein the claim 1 initially and essentially provides that in the device, the tool spindle axis is pivoted about a parallel to the workpiece spindle axis axis of rotation so that their inclination angle about this axis along with the change of the center distance changes.

The claim 2 provides, first and foremost, that in the process during the feed, the inclination angle of the tool spindle axis about a tilting axis extending essentially parallel to the workpiece spindle axis is changed along with the changing center distance.

According to this development, in particular face gears, such as, for example, serrations or also conically running toothings can be achieved with flanks which run towards the center of the workpiece. In a Further development of the invention provides that the change in the inclination angle takes place in accordance with a predetermined function of the axial spacing. In particular, it is provided that the direction of the change in the angle of inclination corresponds to the direction of rotation of the workpiece spindle as the center distance increases. Furthermore, it can be provided that the inclination angle is changed such that the cutting direction of the workpiece relative to the cutting direction taking place at different radial spacings are substantially parallel to one another. With the method and Vorrich¬ direction and bevel gears are generated. In a machine-related coordinate system, the workpiece spindle axis lies in the Z-axis. The radial direction then corresponds to the X-axis. The tool spindle axis lies essentially in the Y axis and in the X direction offset from the Z axis. The offset in the X direction is the radial distance. The feed has at least one component in the direction of the X-axis. The variation of the tilt angle occurs within the XY plane. In this case, the tool axis can have both negative and positive tilt angles with respect to the Y-axis. The feed is preferably carried out in the direction away from the Z axis, ie toward increasing radial distances along the X axis, while the deepest point of engagement of the flywheel on a Z-axis intersecting radial line. As a result of the change in the angle of inclination, the entry points and the exit points of the impact blade in the X direction vary such that the cutting lines are essentially parallel to one another on the workpiece. The pivot axis is preferably not only substantially parallel to the Z-axis, but also in the circulation plane of the flywheel with respect to the cutter head. The cutter head can have a plurality of striking blades which are equally spaced in the circumferential direction and located in a common plane. With the invention plan flanks can be achieved with high accuracy.

Embodiments of the invention are explained below with reference to accompanying drawings. Show it: Fig. 1 is a schematic representation of the geometric arrangement of

Workpiece and tool,

2 is a plan view of the arrangement shown in Fig. 1 in the Y direction,

3 is a section along the line III-III in Fig. 2, looking X-

Direction,

4 is a section along the line IV-IV in Fig. 3, viewing direction Z-

Direction, wherein the beater blade is shown in three different feed positions Rl, R2, R3,

5 shows a schematic illustration which is greatly distorted for clarity in different feed positions of successively produced individual sections 10 on a workpiece end face in the reference system of the workpiece, wherein the inclination angle φ of the tool axis has remained unchanged;

6 is a view according to FIG. 5, but with the inclination angle φ changed in the course of increasing the axial distance R,

FIG. 7 shows an illustration approximately according to FIG. 4 for clarifying the change in the cutting direction 5 ¹ of the flywheel 5 in the machine-fixed reference system as a function of the axial distance R, FIG.

8 shows an illustration according to FIG. 2 of a second exemplary embodiment of the method for producing a serration, FIG. 9 shows a third embodiment in a representation according to FIG. 2 for producing a serration, FIG.

10 is a view according to FIG. 2 of a fourth embodiment for producing a conical circumferential toothing and FIG

11 shows a representation according to FIG. 7, wherein the feed also has a movement component in the Y direction.

The overview representation shown in FIG. 1 shows a workpiece 1, which is driven in rotation in the direction of the circumferential axis shown there around a workpiece spindle axis 2. The drive motor and the work piece 1 receiving the workpiece spindle are not shown for the sake of clarity. The end face of the tool 1 is to be provided with a serration, this consists of radially extending star-shaped teeth.

The tooth gaps are to be produced in the machining process. This purpose is served by the cutter head, which is designated by the reference number 3 and which is shown as a cylindrical body for the sake of simplicity, which is rotated about a tool spindle axis 4. The tool spindle and the tool spindle motor are also not shown here for the sake of clarity. The illustration shows that the flywheel blades 5, which are assigned to the cutter head 3 in a uniform circumferential distribution, lie in a common plane. This plane passes through the inclination axis 12, designated by the reference numeral 12, about which the tool spindle axis 4 is pivotable in the direction -φ or + φ in the XY plane. The inclination axis 12 runs parallel to the Z axis of the machine-fixed reference system forming the workpiece spindle axis. The tool spindle axis 4 is roughly in the direction of the Y axis. The delivery of the cutter head 3 with respect to the workpiece 1 takes place in the direction of the Z axis and is denoted by S. The feed takes place in a direction transverse to the Z axis, namely in the X direction and is denoted by R. With R, the respective distance of the lowest point of engagement of the flywheel 5 is designated by the workpiece spindle axis 2. In the case of the method illustrated in the first embodiment, the feed takes place away from the workpiece spindle axis, so that the radial distance R increases during the feed. According to the invention, it is provided that along with this change in the radial distance R, the inclination angle φ of the tool spindle axis 4 varies within the XY plane. In this case, the inclination angle φ preferably changes only in one direction, namely in the direction of rotation of the workpiece 1. The change takes place continuously.

In the schematic diagram shown in FIG. 2, the reference numeral 9 represents an auxiliary line which runs parallel to the groove bottom 7. The drawn auxiliary line serves to clarify the technical effect of an embodiment of the method and in particular the technical success of the pivoting in the course of the radial feed, since the flanks of the teeth become wider as the radius increases. The auxiliary lines indicate the course of grooves milled with the method when the feed path is so small that the surface of the workpiece is only scratched with the flywheel knives. The time at which the beater blade 5 dives through the plane defined by the auxiliary line 9 is denoted by h. The time at which the cutting blade 5 reaches its greatest depth of immersion into the workpiece 1 is denoted by t ₂ at t ₂ and the time at which the beater 5 passes the plane defined by the auxiliary line 9 in the direction of exchange. If the angle of inclination φ were constant over the entire feed rate V, ie at each axial distance R, then the immersion time h and the dipping time t3 would correspond to the same rotation angle O) ₁ or GQ _{3 of} the workpiece 1 independently of the radial distance R it roughly in Fig. 5 simplified and with an exaggerated large distance between O) ₁ , 0) 2 and 0) 3 and the auxiliary lines 9 is shown. From Fig. 5 it can be seen that at these ratios, the cutting lengths of the individual sections 10 between the auxiliary lines 9 with increasing radial distance R are greater and with respect to the workpiece 1 have different relative cutting directions 11. This has the consequence that the flank angle of the tooth flanks changes in the radial direction. Radially outside, the flanks are flatter. Over their length of extension, the flanks are thus restricted or twisted.

FIG. 4 shows how the inclination angle φ changes as the radial distance R increases. At the radial distance Rl the tool spindle axis 4 is inclined by an angle φl in the counterclockwise direction to the Y-axis. The angle of inclination φ changes in a clockwise direction with increasing radial distance R. It is equal to zero here only as an example for the radial distance R2. Preferably, the inclination angle φ has only positive values. In the further enlarged Radial¬ distance R3, the tool spindle axis 4 is inclined clockwise by the angle φ3 relative to the Y-axis.

The accompanying individual sections 10 between the auxiliary lines 9 are shown in FIG. 6. Here, too, the representations correspond to low tool deliveries, so that only a small amount is worked into the material surface with the tip of the flywheel knife. As can be seen from the figure, the cutting directions 11 of the individual sections run there substantially parallel to one another. The immersion points h and the points of exchange t lie on parallel lines, namely the auxiliary lines 9.

Fig. 7 shows that the path 5 ^{1 of} the cutting tip of a flywheel 5 in the radial positions Rl and R3 is inclined to the XZ plane. This has the consequence that the flywheel in the radial position Rl not in the Drehwin- kelstellung ωl, but in an offset by Δω rotational position in the of Auxiliary line 9 dips defined plane and emerges in an offset by Δω in the opposite direction rotational position relative to αθ from this plane. In the radial position R3, the beater blade 5 dips into and out of angular positions offset by a quantity Δω in the opposite direction, so that the cutting lengths of the individual slices 10 are essentially of equal length.

As can be seen from FIG. 2, in the case of a groove base 7 extending transversely to the workpiece spindle axis 2, an obliquely extending ridge cloth 8 forms. If the feed motion V is superimposed on a movement direction in the -Z direction, as shown in FIG. 8, the groove bottom 7 ¹ receives a corresponding inclination to the transverse direction to the workpiece spindle axis 2. The corresponding ridge line 8 ¹ can be selected with appropriate selection of the Feed in Z direction then run exactly in the transverse direction to the workpiece spindle axis 2. As a result, the spur-toothed gear produced by the method according to FIG. 8 has a complementary toothing, to the end-toothed gear manufactured by the method illustrated in FIG. If these two gears 1, V are placed against each other, the tooth flanks lie flat against each other, so that a torque transmission is possible.

Alternatively, however, the movement component in the -Z direction of the feed V can also be selected such that both the groove base 7 "and the ridge line 8" run at the same angle to the transverse direction to the workpiece spindle axis 2. The front-toothed gears thus produced are then complementary to one another.

In these methods, also shown in FIGS. 8 and 9, the auxiliary lines 9 ¹ , 9 ", for which the conditions according to FIG. 6 apply, extend parallel to the groove 7 ', 7". In the embodiment shown in FIG. 10, the feed V has only a small radial component R. Here, too, an auxiliary line 9 '"runs parallel to the groove bottom 7", so that the conditions shown in FIG. 6 apply. Unlike in the previously discussed embodiments, however, the feed from radially outward to radially inward takes place here, that is, toward the workpiece spindle 2. The pivoting direction of the cutter head 3 about the inclination axis 12 must be adjusted accordingly.

According to the illustrations of FIG. 11, it is not only possible to displace a component of movement in the Z-direction to the feed. It is also possible to superimpose a direction of movement in the Y direction to the feed.

The swivel angle φ is changed in such a way with the changing axial distance R, that each change of the axial distance also corresponds to a change of the swivel angle. In the simplest case there is a proportional relationship between the pivoting angle φ and the radial distance R. However, the functional relationship R of φ may also be more complicated. Mathematically, this relationship can be represented by a superposition of higher-order polynomials. The functional relationship can be determined by model calculations or by experiments.

The diameter of the tool, ie the circle diameter of the cutting edge, is preferably larger than the diameter of the workpiece to be toothed. As a result, the individual sections may be significantly longer than shown in the rough schematic representations. In particular, the rotational speed or the inclination φ is matched to the radial distance in the workpiece such that the individual sections lie essentially in the alignment position one behind the other. In this case, the individual individual sections often overlap to produce the flattest possible flank. As already stated above, the angles of inclination should preferably be only positive, so that the first cut in a winch kel φ is started equal to zero. Any deviations still present from the ideal flank design can be compensated for by additionally "shifting" the cutter head in the Y direction. The knife head swiveled in the X direction during its displacement is then additionally displaced in the Y direction, so that its path runs inclined to the X axis.

All disclosed features are essential to the invention. The disclosure of the associated / attached priority documents (copy of the prior application) is hereby also incorporated in full in the disclosure of the application, also for the purpose of including features of these documents in claims of the present application.

Claims

1. A device for toothing of workpieces (1, V, 1 ", 1 '") with a tool spindle and a workpiece spindle, which are rotatably driven in a fixed speed ratio to each other and whose axes (2, 4) have a center distance (R) in which the tool spindle carries at least one cutter head (3) having a cutting tool (5) which can be fed onto the workpiece (1, V, 1 ", 1 '") and during the machining of the workpiece (1, V, 1 ", 1 '") in a feed direction is continuously displaceable, wherein the feed direction (V) one in the

Axial distance direction (R) extending radial component, da¬ characterized in that the tool spindle axis (4) in such a substantially parallel to the workpiece spindle axis (2) extending Nei¬ transmission axis (12) is pivotable that their inclination angle (φ) about this axis (12) changes with the change of the center distance (R).

2. Method for toothing workpieces (1, V, 1 ", 1 '") with the features:

a workpiece to be toothed (1, V, 1 ", 1 '") is rotationally driven by a workpiece spindle about a workpiece spindle axis (2);

a cutter head (3) having at least one beater blade (5) is driven in rotation by a tool spindle about a tool spindle axis (4);

- The tool spindle and the workpiece spindle run in a fixed speed ratio to each other; - The tool spindle axis (4) and the workpiece spindle axis (2) have a center distance (R) to each other;

- The feed (V) has a radial component in the direction of Achsab- estate (R);

characterized in that during the advance (V) the angle of inclination (φ) of the tool spindle axis (4) about an inclination axis (12) running essentially parallel to the workpiece spindle axis (2) merges with the changing center distance (R). will be changed.

3. Device according to claim 1 or in particular, or method according to claim 2 or in particular according thereto, characterized in that the change of the inclination angle (φ) according to a predetermined, in particular monotonically increasing or decreasing function of the axial distance

(R) takes place.

4. The device or method according to one or more of the vorhergehen¬ claims or in particular according thereto, characterized in that the direction of the change of the inclination angle (φ) ent¬ at greater werden¬ the axial distance (R) of the direction of rotation of the tool spindle (2) ,

5. A device or method according to one or more of the preceding claims or in particular according thereto, characterized in that the inclination angle (φ) is changed such that the on the workpiece (1, V ₁ 1 ", 1 '") related cutting direction (11) of the individual sections (10) taking place on one another in different radial distances (R) run essentially parallel to one another.

6. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the workpieces are toothed with a plan, in particular a Hirth toothing.

7. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the workpieces are toothed with a Ums toothing, the teeth tapered duri fen.

8. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the workpieces are Kegel¬ wheels.

9. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the feed (V) before a movement component in the Y direction has.

10. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the feed has a component of movement in the Z direction.

11. The method according to one or more of the preceding claims or in particular according thereto, characterized in that the Schwenkbewe¬ movement about the inclination axis (12) starts at an angle φ, which is equal to zero.