Method for producing a torsional profile from a blank, and torsional profile

Abstract

The invention relates to a method for producing a torsional profile from a blank. The torsional profile has torsionally rigid tubular end sections, a torsionally flexible U-shaped middle longitudinal section and, between the middle longitudinal section and the end sections, transition sections which change from the U-shaped cross section to the tubular cross section.

Claims

1. A method for producing a torsional profile from a blank, which torsional profile has torsionally rigid tubular end sections, a torsionally flexible U-shaped middle longitudinal section and, between the middle longitudinal section and the end sections, transition sections which change from the U-shaped cross section to the tubular cross section, comprising: a) forming a longitudinally oriented U-shaped depression into the blank at a distance from the face ends thereof, so as to form legs which extend away from the depression; b) bending the legs of the deformed blank adjacent to the depression such that said legs are arranged substantially parallel to one another and to the middle longitudinal plane of the depression; c) deforming the bent legs into a tubular shape in the regions adjacent to the face ends of the blank, and deforming the bent legs into a U-shape in the longitudinal section with the depression, in a manner adapted to the contour of the depression, longitudinal edges of the bent legs being arranged facing one another over their entire longitudinal extent; and d) introducing at least one spacer into the deformed blank such that the bent legs and delimiting walls, which extend in the direction of longitudinal edges of the middle longitudinal section, of the depression are held spaced apart in the middle longitudinal section, wherein the at least one spacer is arranged between the longitudinal edges of the bent legs.

2. The method as claimed in claim 1, wherein a protruding bulge is formed out of the base of the depression in the direction of the longitudinal edges of the middle longitudinal section.

3. The method as claimed in claim 1, further comprising: joining the longitudinal edges of the deformed legs to the at least one spacer.

4. The method as claimed in claim 3, wherein the joining is performed by way of a welding process.

5. A torsional profile produced from a blank comprising: torsionally rigid, tubular end sections; a torsionally flexible, U-shaped middle longitudinal section which forms a depression; and between the middle longitudinal section and the end sections, transition sections which change from the U-shaped cross section to the tubular cross section, the middle longitudinal section being formed such that bent legs and delimiting walls, which extend in the direction of the longitudinal edges of the middle longitudinal section, of the depression are arranged adjacent to one another, wherein at least one spacer is provided, by means of which the bent legs and the delimiting walls of the depression are held spaced apart in the middle longitudinal section, and wherein at least one spacer is arranged between longitudinal edges of the bent legs.

6. The torsional profile as claimed in claim 5, wherein the at least one spacer is joined to the longitudinal edges of the bent legs.

7. The torsional profile as claimed in claim 6, wherein the at least one spacer is welded to the longitudinal edges of the bent legs.

8. The torsional profile as claimed in claim 5, wherein the spacing between the bent legs and the delimiting walls of the depression is uniform over the middle longitudinal section.

9. The torsional profile as claimed in claim 5, wherein, in the region of the joints, the depression has a protruding bulge which extends out of the base so as to form a free space in the direction of the longitudinal edges of the middle longitudinal section.

10. The torsional profile as claimed in claim 5, produced in accordance with a method that comprises: a) forming a longitudinally oriented U-shaped depression into the blank at a distance from the face ends thereof, so as to form legs which extend away from the depression; b) bending the legs of the blank adjacent to the depression such that said legs are arranged substantially parallel to one another and to the middle longitudinal plane of the depression; c) deforming the bent legs into a tubular shape in the regions adjacent to the face ends of the blank, and deforming the bent legs into a U-shape in the longitudinal section with the depression, in a manner adapted to the contour of the depression, longitudinal edges of the bent legs being arranged facing one another over their entire longitudinal extent; d) introducing at least one spacer into the blank such that the bent legs and delimiting walls, which extend in the direction of longitudinal edges of the middle longitudinal section, of the depression are held spaced apart at least in regions; and e) joining the longitudinal edges of the bent legs to the at least one spacer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows an exemplary embodiment of a torsional profile according to the invention in a perspective illustration,

(2) FIGS. 2 to 5 show various method steps during the production of an exemplary embodiment of a torsional profile according to the invention, in perspective illustrations,

(3) FIG. 6 shows a cross-sectional illustration of the torsional profile of FIG. 5, perpendicularly with respect to the central longitudinal plane of the depression of the torsional profile,

(4) FIG. 7 shows the torsional profile as per FIG. 6 after the introduction of a spacer,

(5) FIG. 8 shows the torsional profile as per FIG. 7 after the joining of the spacer,

(6) FIG. 9 shows a further exemplary embodiment of a torsional profile according to the invention, before the final joining process, and

(7) FIG. 10 shows the torsional profile as per FIG. 9 after the final joining process.

DETAILED DESCRIPTION

(8) FIG. 1 shows an exemplary embodiment of a torsional profile 1 according to the invention in a perspective illustration. The torsional profile 1 in this case has torsionally rigid, substantially circular, tubular end sections 2, a torsionally flexible, U-shaped middle longitudinal section 3, and, between the middle longitudinal section 3 and the end sections 2, transition sections 4 which change from the U-shaped cross section to the tubular cross section. In this case, the torsional profile 1 is equipped, in the middle longitudinal section 3, with a depression 11, such that owing to said depression 11, the middle longitudinal section 3 is of U-shaped form. A base 47 of said depression is in this case arranged opposite longitudinal edges 7 which are of ear-like form, wherein the torsional profile 1 is thus of double-layered or double-walled form in the middle longitudinal section 3.

(9) The torsional profile 1 is produced from a rectangular metal blank 8, one half of which is illustrated in FIG. 2. The other half is of mirror-symmetrical design, such that below, in FIGS. 3 to 5, only said one half will be illustrated and described.

(10) For the manufacture of the torsional profile, those regions 10 of the blank 8 which are adjacent to the face ends 9 are firstly deformed into an S-shape. The tools used for this purpose are not illustrated in any more detail.

(11) Subsequently, the thus deformed blank 8 is equipped, between the S-shaped regions 10, with a U-shaped depression 11. To produce the depression 11, the blank 8 is placed between an upper tool (not illustrated here) and a lower tool (likewise not illustrated here). The upper tool defines, by way of a bulge, the inner contour of the depression, whereas the lower tool, with a channel, serves as a counterbearing and defines the outer contour.

(12) The depression 11 is formed centrally into the blank 8 such that legs 14 and 15 of approximately equal width are formed adjacent to the depression 11. A blank 8 thus deformed is illustrated in FIG. 3. In a subsequent working step, by means of a further upper tool (not illustrated here) and a lower tool (likewise not illustrated here), the legs 14 and 15 of the blank 8, which remain approximately identical, are bent adjacent to the depression 11 so as to be substantially parallel to one another and to the central longitudinal plane of the depression 11. A correspondingly deformed blank 8 is illustrated in FIG. 4.

(13) The blank 8 that has been deformed as in FIG. 4 is subsequently reconfigured, using further tools, such that the legs 14 and 15 are deformed into a tubular shape in the ends of the deformed blank 8, such that their longitudinal edges 35 and 36 make contact, and are deformed into a U-shape in the middle longitudinal section 3 with the depression 11. A blank 8 thus deformed is shown in the illustration of FIG. 5.

(14) FIG. 6 then shows a cross-sectional illustration of the blank, deformed as per FIG. 5, in the region of the middle longitudinal section 3. Here, it can be very clearly seen that the legs 14 and 15 bear against and make contact with delimiting walls 54 and 55 of the depression 11. The longitudinal edges 35 and 36 of the legs 14 and 15 are in this case situated facing one another with the formation of a gap 42. Opposite said gap, the depression 11 is equipped, in its base 47, with a bulge 48 such that a free space 49 is formed between the legs 14 and 15 and the delimiting walls 54 and 55 in the region of the gap 42.

(15) To prevent contact of the legs 14 and 15 with the delimiting walls 54 and 55, a spacer 50 is introduced into the gap 42. In this case, the legs 14 and 15 are pushed apart again slightly, such that they are then no longer in contact with the delimiting walls 54 and 55 of the depression 11. The configuration of a blank 8 thus deformed is illustrated in FIG. 7, wherein it can be clearly seen that a gap is formed between the leg 14 and the delimiting wall 54 and between the leg 15 and the delimiting wall 55. To then fix the thus deformed blank 8, the spacer 50 is cohesively connected to the legs 14 and 15 with the formation of joints 61 and 62, which in the case of welding are in the form of weld seams. After the joining process, the torsional profile 1 according to the invention is then complete. In this case, said torsional profile 1 has, in its middle longitudinal section 3, which can be subjected to torsional load, no points of contact between the legs 14 and 15 and the corresponding delimiting walls 54 and 55, such that, under torsional load of the torsional profile, generation of noise owing to legs 14 and 15 and delimiting surfaces 54 and 55 rubbing against one another is prevented.

(16) A further exemplary embodiment of a torsional profile 1 according to the invention is illustrated in FIGS. 9 and 10. As can be clearly seen here, in this exemplary embodiment, no spacer is inserted in the gap 42 between the longitudinal edges 35 and 36 of the legs 14 and 15. Rather, in this case, in each case one separate spacer 51 and 52 is inserted between the leg 14 and the delimiting wall 54 and between the leg 15 and the delimiting wall 55.

(17) The spacer 51 spaces the leg 14 apart from the delimiting wall 54, whereas the spacer 52 spaces the leg 15 apart from the delimiting wall 55. Here, in order that no generation of noise occurs under torsional load of the torsional profile 1, it has proven to be advantageous for said spacers 51 and 52 to be formed from a solid lubricant, for example graphite, graphene, molybdenum sulfide or polytetrafluoroethylene. These materials exhibit particularly good sliding characteristics, such that no generation of noise, or no generation of noise that is perceptible to human hearing, occurs under torsional load, when said spacers 51 and 52 are moved against the legs 14 and 15 or the delimiting walls 54 and 55.

(18) In order that a closed profile is formed in this exemplary embodiment too, the longitudinal edges 35 and 36 of the legs 14 and 15 of the blank 8 thus deformed are joined, in particular welded, to one another. Such a joint 62 is shown in FIG. 10 and, in the case of a metallic blank, is preferably in the form of a weld seam.

(19) The spacers 51 and 52 may be correspondingly placed during different method steps during the production of the torsional profile 1 according to the invention. Firstly, the rectangular blank 8 may already be equipped with corresponding spacers 51 and 52. It is however also possible for said spacers to be correspondingly placed during other production steps during the method according to the invention.

LIST OF REFERENCE NUMERALS

(20) 1 Torsional profile 2 End section 3 Middle longitudinal section 4 Transition section 7 Longitudinal edge 8 Blank 9 Face end 10 Region 11 Depression 14 Leg 15 Leg 35 Longitudinal edge 36 Longitudinal edge 42 Gap 47 Base 48 Bulge 49 Free space 50 Spacer 51 Spacer 52 Spacer 54 Delimiting wall 55 Delimiting wall 60 Joint 61 Joint 62 Joint