DE838535C - Milling head for milling spur gears with straight and angled teeth with a tapered outer and base - Google Patents

Description

Hermann Pfauter, machine tool factory, Kornwestheim near Stuttgart The requirement for a low level of noise generating three gears listed the manufacture of the above wheels and the improvement of the manufacturing methods, especially for wheels with a large diameter and large wheel width.

Conical spur gears run more smoothly than cylindrical ones because they are cheaper Have meshing conditions and because the game is regulated by axial readjustment can be.

When. The solution to the task of their production is the production of Gear teeth on a normal hobbing machine with combined vertical feed of the tool and horizontal feed of the workpiece become known, with easy Conical wheels with a conical outer and base surface are created. Since the 'cutter at a normal machine is only swiveled in one plane that is parallel to the workpiece axis lies, the milling cutter surface does not touch a cone, but a cylinder, so that it the workpiece intersects. In picture i, point a is the contact point between cylindrical Milling jacket and cylinder jacket one Helical gear (dashed drawn). When milling a conical helical gear (solid lines) the milling cutter penetrates from a along the line b into the thickening wheel casing a. On the one hand, this happens as a function of the cone angle of the workpiece and, on the other hand, the angle of the inclination of the milling cutter (due to the tooth inclination and slope; angle). The wheels produced in this way, especially helical gears, are therefore flawed.

There is also a milling process known in which the cutter under Maintaining the required inclination, moved forward tangentially to the workpiece is (cross feed). Otherwise there will be no feed. The wheel is cut ready, when the scorer, as can be seen in Figure 2, walked from c-d over the area of intervention is. The length of the milling cutter required is very large and depends on the bevel of the tooth and width of the wheel. A cutter that is too short would not machine the entire face width. For wheels with small helical angles, and for straight gears, there are even multi-thread Milling cutter necessary. Their large angle of incline enables only a noteworthy one Milling inclination, which is absolutely necessary. Besides, this works Process relatively uneconomical, since the feed distance c-d is very large is.

It is also known to clamp the workpiece on a table, which can be swiveled by deti cone angle, or the workpiece is opened a non-swiveling table clamped, the machine stand, in particular the guide for the milling slide is swiveled around the taper angle. These procedures lead to difficulties, especially with regard to the even wear of the tooth flanks, when -two wheels working together are milled on different machines, because in these cases the angle setting can only be carried out with great difficulty in relation to one another. Due to the necessary pivoting of the table or stand, the gear train to Workpiece or ehenfaills to the tool can be pivoted, which requires greater effort and experience has shown that the interposition of further gears again causes the problem is too imprecise work.

Setting up the machine with a pivoting stand would make one mean deep interference in the normal construction. In contrast, it goes a long way less inconvenience, according to the 1-rfitidig a normal machine with a special milling head to provide.

The subject matter of the invention now improves the initially described Milling process with perpendicular working fii feeds of tool and Workpiece. in such a way that a flawless - \, Erzalinurig with straight and helical teeth Cylindrical gears are created because the milling cutter surface forms the base circle of the cone during milling affected and not intersected. This last condition has not yet been met will. The invention is shown in Figures 4 to 8, for example. the Figures i and 2 serve to explain the state of the art. It shows picture i penetration of the hob into the thicker cone part when hobbing conical helical gears on normal hobbing machines, Figure 2 hobbing of narrow conical spur gears by means of cross feed, Figure 3, the transmission plan of a conventional milling head, Figure 4 the gear plan of a milling head according to the invention, Figure 5 the work of a Machine according to Figure 4, shown schematically, Figure 6 Creation of the additional Tooth incline by means of equipment according to Figure q., Figure 7, the gear plan of a milling head according to the invention according to a further improved embodiment, Figure 8 the transmission plan a milling head according to the invention; according to the design according to Fig. 7 with a other type swivel gear.

In a milling head of a hobbing machine is known from a vertical shaft i from over bevel gears 2 and 3 and a and 5 and spur gears 6 and 7 of the milling cutter 8 driven by the rotating part 9 in the pivot angle accordingly the pitch angle and, if necessary, the tooth slope can be set.

The milling head 5, 6, 7, 8 is in the pictures 3 to 8 from its real Position drawn offset by 9o ° minus the angle of inclination and in the plane of the drawing placed.

According to picture d the bevel gears .I and 5 are kept smaller, so they can work together with a crown wheel io, which makes the milling cutter difficult in two planes at right angles to each other. Figure 5 shows how the pivoted milling cutter 8 is set in the taper angle of the workpiece. By this pivoting is a penetration of the cutter jacket in the root cone lengthways the line b of picture i avoided. The milling slide i i and the workpiece slide 12 are both moved in the direction of the arrow so that the cutter is on the resultant Moved roughly in the direction of arrow 13, that is, along a conical surface line of the workpiece.

The milling head shown in Fig. 1 gives the spur gears with oblique teeth due to the sideways swiveling, <i. H. except milling head center stationary hob as well as an additional one due to the radial feed of the workpiece Tooth slope, which depends on the cone angle and the lateral swivel angle of the hob.

Figure 6 shows as follows: a upper cone circumference on the work wheel, b lower cone circumference on the work wheel, v ", dial = radial feed direction, 8 'hob without lateral pivoting, 8" hob with lateral pivoting, 8 lateral pivoting angle, 111-M2 Line center swivel plane 9 - center work wheel.

Since the hob when pivoting about the NI ittclpunkt of the ring gear io hl from the line lierausri.ickt -MZ, he has a dependent on the pivot angle anomalous angular position relative to the work gear and (! Thus i-zetigt in connection with the feed, which no longer runs radially to the milling cutter, <11e mentioned additional tooth bevel. Depending on the direction of the radial feed, this angle has a positive or negative effect on the helical angle of the workpiece .

The milling head shown in FIG. 13Id 7 has what is shown above Disadvantages not, cla by relocating the Drelicbene in front of the Schwenkelaene of the milling cutter, seen in the direction of the milling cutter drive, this in every position ini: machine means remain. The turned part o becomes angled when setting the milling cutter in the Kcgel% with pivoted, namely about a horizontal axis, the projection of which is perpendicular on the radial feed direction.

The additional pivoting of the milling cutter axis is of course also through other means, such as worm gears or helical gears, are possible.

Image S shows an example of an embodiment, where i 'Frä serantriebswelle (horizontal), 2 'worm or alternatively helical gear, 3' worm gear or alternatively Mean helical gear.

The pivoting is done by the horizontally lying axis t ', which (read Wheel 2 'carries and the bearing is connected to the pivot plane g. That had 3 ' its axis perpendicular to the drive shaft i 'and is also in the pivot plane g 'stored.

Claims (3)

PATENT CLAIMS: i. Milling head for hobbing machines for setting of a cylindrical hob of normal length tangential to the tapered base surface of straight and helical gears with a tapered outer and base surface, thereby g, indicates that it swivels the cutter in two mutually perpendicular Flattening made possible by the fact that it contains a transmission with three bevel gears (d., 5, io), whose axes intersect at one point, and that it is around the axis of the intermediate gear is pivotable. 2. Friiskopf for hobbing machines for setting a cylindrical Hobs of normal length tangential to the tapered base surface of straight and helical gears with tapered outer and base, characterized in that the bevel gear swivel gear is arranged between the drive shaft (i) and the rotating part (g), so that he is Swiveling the rotating part (g) is also swiveled, namely into a tapered one Gear shell parallel position. 3. milling head for hobbing machines according to claim i and 2, characterized in that its swivel gear is a helical gear.