Two-stage rolling method and rolling device for ring

(42) Date of commencement of the patent: 15. 9.1988 (45) Date of issue: 10. 4.1989

<td>(30) Priority:</td><td>(73) Patent owner:</td>

<td>26.11.1984 DD 269866 claimed.</td><td>VEB KOMBINAT ROLLER BEARINGS UNO STANDARD PARTS DD-9022 CARL MARX CITY (DD).</td>

<td>(56) Documents:</td><td>(72) Inventor:</td>

<td>GB-PS1562105 US-PS4506422</td><td>BARTKO KRISTINE DR.ING. DOHMA (DD). GÄBLER DIETER ING. CARL MARX CITY (DD). HEINRICH PETER DR.ING. CARL MARX CITY (DD). LUCKNER JOACHIM DIPL.ING. CARL MARX CITY (DD). SCHLENKRICH BERND ING. CARL MARX CITY (DD).</td>

CQ

AT 387 920 (54) TWO-STAGE ROLLER ROLLER DEVICE (57) Apparatus for two-stage rolling of mostly profiled rings, eg rolling bearing rings, with an increase in diameter in two rolling stages in a sequence for reducing the load on the rolling mandrel. This device can be used primarily in the rolling bearing industry for the production of rolling bearing rings with a relatively small diameter, for which a cutting finishing was previously necessary. As a result, auxiliary times are reduced and considerable material savings are achieved with high labor productivity.

Fig.l

<img file="AT387920B_D0001.tif" />

DUR 0078018

Nr.387920

The invention relates to a device for two-stage rolling of rings according to the principle

Roller mandrel with a two-stage stepped, one pre- and one finish roller profile on facing

Rolling mandrel, which is supported axially displaceably on both sides in hollow shafts.

For the production of annular workpieces rolling processes and devices are known which operate on the principle of roller-mandrel. In this case, the workpiece is received on the mandrel and it is so deformed between it and the roller that its wall thickness is reduced and the diameter is kept constant while the width is kept constant. Since in particular a solidification of the annular material takes place during the deformation, this requires an increase in the required rolling force.

When rolling profiled rings, such as roller bearing rings, a minimum wall thickness of the starting part is required so that the profile can be completely rolled out. Because of the constant width and the volume constancy arise for the output part relatively small diameter. The bore diameter determines the maximum possible diameter. The due to the material flow very small roll mandrel diameter must transmit the maximum deformation force required in the final phase, which leads to high voltages in this. As a result, this known method is not applicable to small ring diameters.

The invention is therefore based on the object to avoid the disadvantages of the known devices, whereby the rolling of rings with a relatively small diameter without a hitherto required cutting machining technically-economically applicable, the entire rolling process is stabilized and by reducing the auxiliary times Significant material savings with high labor productivity is possible.

These objects are achieved according to the invention that in the hollow shafts in each case a ground bushing is fixed, which support the shank of the rolling mandrel during rolling with the finish rolling and that for rolling with the roughing in the ground bushing a sleeve is slidably disposed in a bore the shank of the rolling mandrel is supported.

The object of the invention is explained below with reference to an embodiment shown in the drawings. FIG. 1 shows the rolling mandrel bearing in section and FIG. 2 shows a section along the line II-II of FIG.

On a common base frame, not shown, two bearing housings -1, 2 attached axially adjustable. In between are a roller -15- and a holder -18- for a support roller -16-. In the bearing housing -1- a hollow shaft -4- is stored by means of bearings -3-, in which a rolling mandrel -5- provided with a rough-rolling profile -6- and a finish-rolling profile -7- via a ground bushing -8- by means of drivers -9 and 11 - Is mounted rotatably and axially displaceable. For receiving the pin of the rolling mandrel -5- with the diameter Dl of Vorwalzprofils -6- a sleeve -10- is formed with a bore -19-. The outer diameter of the sleeve -10- corresponds to the shaft with the diameter D2 of the finish rolling profile -7-. The sleeve -10- is connected by drivers -9 and 11- rotatably and axially displaceable via a base bush -12- with a hollow shaft -13- connected. This is by means of bearings -3- stored in the bearing housing -2-. Above the rolling mandrel -5- is the ring to be rolled -14-.

In Figure 2, the ring -14- with the rolling mandrel -5- between the roller -15- and the support rollers -16 and 17-, which are arranged in a guided in the base frame support roller receptacle -18-, shown.

In the initial position are the roll mandrel -5- and the support roller receptacle -18- with the support rollers -16 and 17- in the rear position and the sleeve -10- in the forward position.

With the initiation of the rolling process, the rolling mandrel -5- is introduced through the mandrel closing force F1 through the inserted ring 14- through into the bore 19- of the bushing -10-. By a much larger counterforce force F2, which acts via the sleeve -10- against an inner stop, not shown, the rolling mandrel -5- is held securely in this roughing position, wherein the rolling of the first stage takes place.

With the introduction of the support roller force F3 shortly before the completion of the pre-rolling, the support rollers -16 and 17- mounted in the support roller support 18 are attached to the ring 14.

No.387920 pressed. In this finish rolling position, the enlarged diameter ring -14- is held securely by means of the support rollers -16, 17- and the roller -15-, without having contact with the rolling mandrel -5.

With the reduction of the counterforce force F2 against the mandrel closing force Fl moves ⁵ the rolling mandrel -5- with the sleeve -10-, which acts against an outer stop, not shown, by the centrally to him by means of the support rollers -16 and 17- held ring -14-, wherein the shaft with the diameter D2 of the finish rolling profile -7- in the

Hole of the ground socket -12- is introduced.

After finish rolling, the sleeve -10- by the counterforce force F2 in the ¹⁰ moved forward position and are brought by reversing the mandrel clamping force Fl and the support roller force F3 of the mandrel -5- and the support roller receptacle -18- back into the rear position.

After the ring change, the rolling process can be started again.