Method for producing an internally structured slide bearing bushing

Abstract

A method for producing an internally structured slide bearing bushing involves the following steps: a) providing a slide bearing bushing with at least one bearing region which is formed as a hollow cylinder with an internal surface and which has an external diameter and an internal diameter, b) providing an external tool with a through-opening, c) providing an internal tool which has an integral cylindrical operating region with an external surface with a structure, d) inserting the internal tool into the bearing region of the slide bearing bushing, e) introducing the slide bearing bushing and the internal tool into the conical widened portion of the through-opening of the external tool, f) pressing the slide bearing bushing into the through-opening of the external tool, g) removing the slide bearing bushing from the through-opening of the external tool, and h) radially widening the slide bearing bushing.

Claims

1. A method for producing an internally structured slide bearing bushing comprising the steps of: roll-forming a strip material into a slide bearing bushing with at least one bearing region which is formed as a hollow cylinder with an internal surface and which has an external diameter, an internal diameter and a butt joint extending parallel to the axis thereof; providing an external tool with a through-opening, the smallest internal diameter of the through-opening being smaller than the external diameter of the bearing region of the slide bearing bushing, the through-opening on at least one side having a conical widened portion having a maximum internal diameter larger than the external diameter of the bearing region of the slide bearing bushing; providing an internal tool which has an integral cylindrical operating region with an external surface with a structure, the maximum external diameter of the operating region being smaller than the internal diameter of the bearing region of the slide bearing bushing; inserting the internal tool into the bearing region of the slide bearing bushing; introducing the slide bearing bushing and the internal tool into the conical widened portion of the through-opening of the external tool; pushing the slide bearing bushing and the cylindrical operating region of the internal tool together through the through-opening of the external tool with a stop provided on a flange of the internal tool, reducing the external and internal diameters of the bearing region of the slide bearing bushing so that the internal surface of the bearing region is pressed onto the external surface of the internal tool and an internal structure is stamped into the internal surface of the bearing region as a negative shape of the structure of the external surface of the internal tool; pushing the slide bearing bushing completely through the through-opening of the external tool; and radially widening the external diameter of the slide bearing bushing so that the internal tool is able to be removed from the slide bearing bushing by contact between the slide bearing bushing and the external tool and withdrawn from the through-opening of the external tool, whereby the radial widening takes place by widening the butt joint.

2. The method according to claim 1, characterized in that the internal structure of the slide bearing bushing comprises spatially defined recesses and/or raised portions.

3. The method according to claim 1, characterized in that the slide bearing bushing consists of a compact material having resilient properties and the radial widening takes place by utilizing the resilient properties of the material.

4. The method according to claim 1, characterized in that the radial widening takes place by heating the slide bearing bushing, utilizing the thermal expansion of the material.

Description

(1) Exemplary embodiments of the invention are described in more detail with reference to the schematic drawings.

(2) In the drawings:

(3) FIG. 1 shows schematically a cross section of the tool arrangement at the start of the production method,

(4) FIG. 2 shows schematically a cross section of the tool arrangement when introducing the internal tool into the slide bearing bushing,

(5) FIG. 3 shows schematically a cross section of the tool arrangement after introducing the internal tool into the slide bearing bushing,

(6) FIG. 4 shows schematically a cross section of the tool arrangement when pressing the slide bearing bushing into the external tool,

(7) FIG. 5 shows schematically a cross section of the tool arrangement when pressing the slide bearing bushing into the external tool shortly before the completion of the pressing process,

(8) FIG. 6 shows schematically a cross section of the tool arrangement after the completion of the pressing process,

(9) FIG. 7 shows schematically a cross section of the tool arrangement when removing the internal tool,

(10) FIG. 8 shows schematically a cross section of the tool arrangement at the end of the production process,

(11) FIG. 9 shows schematically a cross section of the internal tool,

(12) FIG. 10 shows schematically a cross section of an alternative surface structure of an internal tool, and

(13) FIG. 11 shows schematically a cross section of a further alternative surface structure of an internal tool.

(14) Parts which correspond to one another are provided in all of the figures with the same reference numerals.

(15) FIG. 1 shows schematically a cross section of the tool arrangement at the start of the production method. In this method step the slide bearing bushing 1, the external tool 2 and the internal tool 3 are provided. The internal tool 3 comprises a cylindrically shaped operating region 30 which has a structure 31. This structure 31 is stamped in a subsequent method step in the bearing region 10 of the slide bearing bushing 1. In this case, the structure 31 is dome-shaped portions with a relatively rough surface.

(16) On the input side, the cylindrical through-opening 20 of the external tool 2 on the input side end has a conical widened portion 201 in order to introduce the slide bearing bushing 1 into the shaping region. The internal tool 3 has in the central region a flange 32, the stop thereof 321 fixing the position of the slide bearing bushing 1 on the operating region 30. In order to form a stop 321 for the front face of the slide bearing bushing 1, the diameter of the flange 32 is larger than the internal diameter of the bushing. The axial force transmission originates from a punch 33 which is connected to the flange 32. The internal tool 3 may be configured in one piece or in multiple parts. In multipart embodiments, if required, the operating region 30 may be replaced in order to use different structures 31, for example.

(17) FIG. 2 shows schematically a cross section of the tool arrangement when inserting the internal tool into the slide bearing bushing 1. The bearing region 10 located on the inner face of the slide bearing bushing 1, in this case, is pushed over the operating region 30 of the internal tool 3 in the direction of the stop 321 on the flange 32. During this insertion the structure 31 does not yet engage in the bearing region 10. The slide bearing bushing 1 in this case is not yet in the engagement region of the external tool 2.

(18) FIG. 3 shows schematically a cross section of the tool arrangement after inserting the internal tool 3 into the slide bearing bushing 1. After the slide bearing bushing 1 comes into contact with the stop 321 of the flange 32, said slide bearing bushing is entrained by the internal tool 3 into the external tool 2.

(19) FIG. 4 shows schematically a cross section of the tool arrangement when pressing the slide bearing bushing 1 into the external tool 2. In this method step, the slide bearing bushing 1 is shaped in the external tool 2. In this case, the slide bearing bushing 1 is pressed through the narrower through-opening 20 and reduced in diameter. This takes place on the inner face of the slide bearing bushing 1 such that the structure 31 in the operating region 30 of the internal tool 3 is pressed into the bearing region 10.

(20) FIG. 5 shows schematically a cross section of the tool arrangement when pressing the slide bearing bushing 1 into the external tool 2 shortly before the completion of the pressing process. In this method step, the slide bearing bushing 1 is pressed together with the internal tool 3 by the external tool 2 axially over the entire length thereof.

(21) FIG. 6 shows schematically a cross section of the tool arrangement after completion of the pressing process. In this method step, the slide bearing bushing 1 emerges from the through-opening 20 of the external tool 2. Due to the resilient properties of the material of the slide bearing bushing 1, said slide bearing bushing is widened in the radial direction and again releases the internal tool 3.

(22) FIG. 7 shows schematically a cross section of the tool arrangement when removing the internal tool 3. The internal tool 3 in this case is axially pulled out of the external tool 2 in the opposing direction to the pressing direction, and at the same time slides over the slide bearing bushing 1. In the bearing region 10, the internal structure 11 is now shaped as recesses 12 and raised portions 13 in the surface.

(23) FIG. 8 shows schematically a cross section of the tool arrangement at the end of the production process. In this basic position of the external tool 2 and the internal tool 3, a further slide bearing bushing may be incorporated into the process once again.

(24) Moreover, FIGS. 9 to 11 show advantageous embodiments of the structure 31 of the operating region 30 of an internal tool 3. FIG. 9 shows schematically a cross section of the internal tool with dome-shaped portions having a relatively rough surface. The operating region 30 is defined by the flange 32 to which the punch 33 is adjoined for the force introduction. In the method step, the axial pressing and pulling forces are introduced via the punch 33. FIG. 10 shows schematically a cross section of an alternative surface structure of an internal tool. This is a further variant of a structure 31 with dome-shaped portions having a smooth surface. The domes are designed to be the same in terms of shape and size. However, a cross section of a further alternative surface structure of an internal tool is shown schematically in FIG. 11. The domes of different size are arranged statistically in the operating region 30.

LIST OF REFERENCE NUMERALS

(25) 1 Slide bearing bushing 10 Bearing region 11 Internal structure 12 Recesses 13 Raised portions 2 External tool 20 Through-opening 201 Widened portion 3 Internal tool 30 Operating region 31 Structure 32 Flange 321 Stop 33 Punch