Method for producing a sintered part with high radial precision, and set of parts comprising joining parts to be sintered

Abstract

The invention relates to a method for producing a sintered part with a high radial precision. The sintered part is made of at least one first joining part to be sintered and a second joining part to be sintered, and the method has at least the following steps: joining the first joining part with the second joining part, and bringing about the high radial precision, having a step of deforming at least one radial deformation element which is preferably positioned so as to adjoin a joint contact zone, wherein the deformation of the radial deformation element is caused at least by means of a calibration tool and is carried out at least substantially as a plastic deformation of the radial deformation element. The invention further relates to a set of parts for joining the joining parts to be sintered into a sintered part with a high radial precision.

Claims

1. A method for producing a sintered part with highly accurate radial precision, wherein the sintered part is produced from at least a first sintered joining part and a second sintered joining part, the method comprising at least the following steps: joining the first sintered joining part with the second sintered joining part, imparting the highly accurate radial precision, having a step of deforming at least one radial deformation element, wherein the deformation of the radial deformation element is effected at least by way of a calibration tool and takes place at least substantially as a plastic deformation of the radial deformation element, wherein an outer deformation part is, during the course of the joining process, positioned so as to at least partially encircle at least the first sintered joining part and the outer deformation part forms a radial deformation element in the form of an outer radial deformation element.

2. The method as claimed in claim 1, wherein an inner deformation part is, during the course of the joining process, positioned so as to at least partially cover at least a first inner joining surface of the first sintered joining part and/or so as to at least partially cover at least a second inner joining surface of the second sintered joining part, and the inner deformation part forms a radial deformation element in the form of an inner radial deformation element.

3. The method as claimed in claim 1, wherein the outer deformation part is, during the joining process, connected in at least one of frictionally engaging, positively locking, non-positively locking and cohesive fashion to at least one of the sintered joining parts, and/or wherein the outer deformation part is, during the imparting of the highly accurate radial precision, connected in at least one of frictionally engaging, positively locking, non-positively locking and cohesive fashion to at least one of the sintered joining parts.

4. The method as claimed in claim 1, wherein the imparting of the highly accurate radial precision is performed at least partially at the same time as the joining of the first sintered joining part and of the second sintered joining part.

5. The method as claimed in claim 1, wherein for the joining, at least one first process step is performed by way of at least one joining tool, and/or, for the imparting of the highly accurate radial precision, at least one second process step is performed by way of a calibration tool in the form of a separate calibration tool and/or by way of a calibration tool in the form of a calibration region of a progressive tool.

6. The method as claimed in claim 1, wherein after the imparting of the highly accurate radial precision, the sintered part is removed from the calibration tool as a sintered part with highly accurate radial precision.

7. The method as claimed in claim 1, wherein for the production of the sintered part, a first joining surface of the first sintered joining part and a second joining surface of the second sintered joining part are pressed against one another under the action of an axial pressing force exerted by way of a pressing tool, wherein the first sintered joining part has at least one first deformation element arranged on the first joining surface and/or the second sintered joining part has at least one second deformation element arranged on the second joining surface, and a deformation of at least one of the deformation elements is effected by way of the pressing against one another.

8. The method as claimed in claim 1, wherein the at least one radial deformation element is positioned adjacent to a joining contact zone.

9. The method as claimed in claim 1, wherein at least 75% of a change in total volume of the sintered parts and the at least one radial deformation element by way of the deforming is realized as a change in volume of the at least one radial deformation element.

10. A method for producing a sintered part with highly accurate radial precision, wherein the sintered part is produced from at least a first sintered joining part and a second sintered joining part, the method comprising at least the following steps: joining the first sintered joining part with the second sintered joining part, imparting the highly accurate radial precision, having a step of deforming at least one radial deformation element, wherein the deformation of the radial deformation element is effected at least by way of a calibration tool and takes place at least substantially as a plastic deformation of the radial deformation element, wherein at least one region of at least one inner joining surface of the first sintered joining part has at least one radial elevation which forms a radial deformation element in the form of an inner radial deformation element.

Description

(1) In the figures:

(2) FIG. 1 shows an exemplary refinement of a sintered part as a stator composed of a sintered joining part and of a second sintered joining part and of a radial deformation element in the form of an outer deformation part;

(3) FIG. 2 shows an exemplary refinement of a sintered part as a stator composed of a sintered joining part and of a second sintered joining part and of a radial deformation element, in the form of an outer deformation part, in cross section;

(4) FIG. 3 shows an exemplary refinement of a sintered part as an oil pump housing composed of a first sintered joining part, of a second sintered joining part and of a visible radial deformation element in the form of an outer radial deformation element;

(5) FIG. 4 shows an exemplary refinement of a sintered part as an oil pump housing composed of a first sintered joining part, of a second sintered joining part and of a visible radial deformation element, in the form of an outer deformation element, in cross section, also illustrating a radial deformation element in the form of an inner deformation part;

(6) FIG. 5 shows an exemplary refinement of a sintered part composed of a first sintered joining part and of a second sintered joining part with a radial deformation element, in the form of a radial elevation, in cross section;

(7) FIG. 6 shows an exemplary refinement of a sintered part composed of a first sintered joining part and of a second sintered joining part with a radial deformation element, in the form of a radial elevation, in a plan view.

(8) FIG. 1 shows an exemplary refinement of a sintered part 1 in an oblique view. The sintered part 1 is a stator of a camshaft adjuster. The sintered part 1 has a first sintered joining part 2 and a second sintered joining part 3 which have been joined together. Furthermore, the sintered part 1 has an outer deformation part 5 which forms a radial deformation element in the form of an outer radial deformation element. The outer deformation part 5 is, in the refinement shown, in the form of a ring. The axial extent 12 of the outer deformation part 5 corresponds to a spacing of a first radial retention projection 13 of the first sintered part from a second radial retention projection 14, wherein, in the refinement shown, the first radial retention projection 13 and the second radial retention projection 14 are also of rotationally symmetrical form with respect to the axis of rotation 15 of the sintered part 1. The first radial retention projection and the second radial retention projection 14 effect axial positioning of the outer deformation part 5. The radial extent of the outer deformation part 5 is, at all points, greater than the radial extent both of the first sintered joining part 2 and of the second sintered joining part 3. It is realized in this way that, during the calibration, a plastic flow of the outer deformation part makes a significant contribution to the imparting of the highly accurate radial precision.

(9) FIG. 2 shows a cross-sectional illustration, encompassing the axis of rotation 15, of the refinement, shown in FIG. 1, of a sintered part 1 with highly accurate radial precision.

(10) FIG. 3 shows a further exemplary refinement of a sintered part 1 in an oblique view. The exemplary refinement in FIG. 3 is an oil pump housing which has a first sintered joining part 2 and a second sintered joining part 3. Furthermore, the sintered part 1 of FIG. 3 has an outer deformation part 5 which is in the form of a ring. The outer deformation part 5 in the form of a ring fully encircles the first sintered joining part 2 and is formed so as to bear against a partial region of the outer shell surface of the first sintered joining part 2. FIG. 3 likewise shows an inner deformation part 4, which is likewise in the form of a ring.

(11) FIG. 4 shows a cross-sectional illustration of the sintered part illustrated in FIG. 3. In addition to the features of the sintered part 1 that already emerge from the illustration of FIG. 3, the illustration shown in FIG. 4 also shows a first retention projection 13 which, together with the second sintered joining part 3, effects axial positioning of the outer deformation part 5. Furthermore, the cross-sectional illustration of FIG. 4 shows an inner deformation part 4 inserted in the interior of the sintered part 1. In the illustration shown, the inner deformation part 4 is likewise in the form of a ring and is inserted in a recess of the second sintered part 3. The dimensions and the geometric design of the ring are such that the inner deformation part 4 completely covers a second inner joining surface 9 of the second sintered joining part 3 over the entire part of its axial extent. The inner deformation part 4 completely covers a first outer joining surface 10 of the first sintered joining part over the entire part of its axial extent. In the refinement shown, the inner deformation part 4 is arranged between the first outer joining surface 10 and the second inner joining surface 9 with an interference fit. By way of the illustrated arrangement of the inner deformation part, it is realized that axial positioning of the first sintered joining part 2 relative to the second sintered joining part 3 with high accuracy is realized as a result of the plastic deformation of the inner deformation part 4, which functions as inner radial deformation element. Axial positioning of the inner deformation part is realized by way of the second retention projection 14, which is formed in the recess of the second sintered joining part.

(12) FIG. 5 shows a further exemplary refinement of a sintered part 1. The sintered part 1 illustrated in FIG. 5 is a sintered part 1 formed from a first sintered joining part 2 and from a second sintered joining part 3 by joining. The first sintered joining part 2 has a recess, the inner shell surface of which forms a first inner joining surface 8. The second sintered joining part 3 has been inserted into the recess. An in particular frictionally engaging connection of the two sintered joining parts has been effected by way of inner radial deformation elements, which are in the form of radial elevations 6 and which are arranged on a second outer joining surface 9 of the second sintered joining part and which are plastically deformed during the insertion of the second sintered joining part 3 into the recess of the first sintered joining part.

(13) While the stated radial elevations cannot be seen in the illustration of FIG. 5, they can be seen in the plan-view illustration of FIG. 6.