CH709554A2 - A method for producing a vehicle wheel rim of fiber reinforced polymer material. - Google Patents

Abstract

In a method for producing a vehicle rim made of fiber-reinforced polymer material in the manufacture of the preform (1) of the rim inside or outside at least one over the entire rim surface extending base laminate layer (9) of fiber-reinforced polymer semi-finished or between over the entire rim surface extending base laminate layers of fiber-reinforced Polymer semi-finished at least in the range of gradations in the rim contour as between rim base and rim shoulder and / or shoulder to rim flange several stored in the circumferential direction of the rim stacked band layers (15-19) made of fiber-reinforced polymer material stored or inserted.

Description

The present invention relates to a method for producing a vehicle rim according to the preamble of claim 1 and a rim for a vehicle.

In the course of weight reduction of vehicles rims of a vehicle wheel are made of fiber-reinforced plastics recently. Such a rim is described in WO 2013/037428. In practice, it has been shown that the production of these rims is relatively expensive by the fiber-reinforced plastic layers used must be cut as a result of the curvature in the circumferential direction of the rim between the so-called rim flange and the rim shoulder and possibly also to the rim base.

It is therefore an object of the present invention to provide a manufacturing method and a correspondingly prepared rim, in which a cutting of the layers is no longer necessary. A further object is basically to simplify the manufacturing process of fiber-reinforced plastic or polymer-made rims in order to enable the most extensive large-scale production.

According to the invention, a method according to the wording of claim 1 and a vehicle rim according to the wording of claim 17 is proposed accordingly.

It is proposed that inserted in the manufacture of extending over the entire rim surface of fiber-reinforced polymer semi-finished at least in the range of gradations in the rim contour as between rim base and rim shoulder and shoulder to rim flange extending in the direction of rotation of the rim stacked tape layers or arranged become.

According to one embodiment, at least on the shoulder and / or on the rim flange in the direction of rotation of the rim extending stacked band layers are arranged before the pressing process of the rim shape molding or preform. However, it is also possible along each section of the rim contour either directly on the preforming tool itself or on a made of several layers of semi-finished inner base laminate tape layers deposit respectively unwound on the sections in layers, wherein finally on the unwound and deposited tape layers an outer is made of several layers existing base laminate.

According to one embodiment, the bandwidth of the unwound band of fiber-reinforced polymer is at least equal to the width of the respective section selected or larger than the width of the respective section, so that optionally laterally the unwound and deposited tape is bent, corrugated or swirled in the subsequent pressing operation ,

But it is also possible to combine in a band stack of the respective section of the rim contour different bandwidths, such that per band layer, for example, two or more bands with different bandwidth next to each other and / or are arranged one above the other. It is advantageous that, in the case of two superimposed layers with a plurality of bands, the dividing lines between the bands are not aligned with each other but are laterally offset relative to each other.

Again, according to a variant embodiment, it is proposed that the stack thickness of the tapes to be unwound or deposited is, for example, at least 2% greater than the thickness of the individual tapes in the pressed rim resulting ultimately after the pressing operation of the preform or preform.

The arranging or winding of the fiber-reinforced polymer tapes on the base laminate is preferably carried out under train. The strips are cut before winding on the base laminate in each case after a certain length of tape, whereupon the resulting two tape ends are arranged overlapping and again firmly connected to a band ring. The joining of the overlapping strip ends can be done, for example, by means of spot welding, for example with a hot pressing tip. Again, it is advantageous to arrange the overlapping fixedly connected ends, two superposed or juxtaposed band rings to each other in the circumferential direction offset.

The number of tape layers per stack in a section of the rim contour can be chosen differently. For example, in the area of the rim flange, less band layers are inserted between the inner and outer base laminate than in the area of the rim shoulder, in which, for example, more layers are inserted than in the region of the rim base. In principle, however, the number of band layers to be arranged per section depends on the requirements of the vehicle rim to be produced. For example, different requirements arise as to whether the rim is used for a vehicle wheel of a small car, a large sedan, a sports car, a truck or a motorcycle. Also, the type of the fiber-reinforced polymer material may be different in nature, such as tear strength, heat conductivity, whipping ability, etc., etc.

In the production of the novel rim made of fiber-reinforced polymer material, a base laminate consisting of several layers of fiber-reinforced polymer semifinished product is first deposited on a preforming tool. For the production of the base laminate from fiber-reinforced polymer semifinished product, reference is moreover made to WO 2013/037 428 and to WO 2012/104 174, in which the production of a so-called preform or fiber-reinforced preform is described in principle.

It has been shown that it may be advantageous if the multilayer structure of the base laminate on a so-called preforming tool initially at least one layer is arranged with at least partially axial fiber flow of semi-finished parts. Subsequently, at least one layer with an inclined fiber direction such as between 30 ° and 60 °, in particular between 45 ° and 60 ° angled to the circumferential direction and subsequently at least one further layer with opposite, again oblique fiber direction such as between -30 ° and -60 ° , in particular between -45 ° and -60 ° angled ie in the opposite direction. The number of layers to be arranged depends, as already mentioned above, on the requirements of the rim to be produced.

The tapes wound thereon in the circumferential direction of the rim have a major fiber direction in the tangential direction, i. E. in the circumferential direction of the rim to be produced. Again, the number of bands depends on the requirements of the rim to be created. The type of fiber selected, fiber architecture, matrix material, etc., such as based on carbon depends on the requirements such as stiffness, thermal conductivity, breaking strength, etc.

Finally, an outer multi-layer base laminate is placed on the example, over the entire surface of the rim arranged individual band stack, which in turn consists of several layers of fiber-reinforced polymer semi-finished product.

The outermost layer of the outer base laminate generally has a fiber direction which extends at least partially axially.

The rim preform or rim preform produced in this way is then pressed in a pressing tool, as described, for example, in WO 2010/092 081.

Finally, a rim of a vehicle wheel according to the wording of claim 14. According to, for example, the previously described method, the proposed rim several layers of fiber-reinforced polymer, wherein at least in some areas of the rim in the radial direction inside or outside of at least one multi-layered Grundlaminats fiber-reinforced polymer semi-finished product or between a multilayer inner base laminate and a multilayer outer base laminate a plurality of extending in the circumferential direction of the rim band stacks are arranged, which can be generated for example by winding the bands in the circumferential direction.

Further preferred embodiments of the inventive method as well as the inventive rim are characterized in dependent claims.

The invention will now be explained by way of example with reference to the accompanying drawings.

[0021] In the following: <Tb> FIG. 1 <SEP> In the form of a schematic diagram, a cross section through a preform or preform of a wheel rim according to the invention, <Tb> FIG. 2 <SEP> A section of the rim cross-section from FIG. 1, <Tb> FIG. 3 <SEP> Schematically the strip thickness of the fiber-reinforced polymer strip used for the production of the preform and the wall thickness after pressing and producing the rim, <Tb> FIG. 4 <SEP> Various band layers with different bandwidth in a partial region of the cross section of Fig. 1, and <Tb> FIG. 5 <SEP> Schematically the periodic cutting of the tape layers during winding on the rim to be produced.

Fig. 1 shows in the form of a schematic diagram a cross section through a preform 1, also referred to as a preform of an inventive wheel rim. The preform 1 of the wheel rim is first formed by a multilayer so-called base laminate 9, which is made of several layers of fiber-reinforced polymer semi-finished product. The base laminate is placed in the production of the preform on a so-called preform tool, which is not shown in Fig. 1. The base laminate 9 of several layers has a lowermost layer, in which the fiber direction extends substantially in the axial direction. On it one or more layers are provided with obliquely to the circumferential direction of the rim extending fiber direction such as angled at about 30 ° to 60 ° and one or more layers also obliquely extending fiber direction, but for example angled in the opposite direction again by about 30 ° up to 60 ° with respect to the circumferential direction. Preferably, angles between ± 45 ° and ± 60 ° are selected.

In contrast to the rim, as proposed in WO 2013/037 428, a plurality of extending in the circumferential direction of the rim tape layers are wound in the various sections of the rim, such as tape ply stack in the rim 15, in the area Rim shoulder 18 or in the area of the rim flange 19. In the stages, for example, from the rim base to the shoulder or the shoulder to the horn, tape layers 17 or 16 which are suitable for this area are also unrolled. Of course, it is possible to choose the band layers differently, for example, that they extend from the shoulder in the area of the step towards the bed, that band layers of the steps extend into the adjacent rim sections, etc. Finally, arranged on the various circumferential band layers is an outer base laminate 11, which in turn is made of several layers of fiber-reinforced polymer semi-finished product. In this case, some layers may again have fiber directions, which are inclined at an angle to the circumferential direction of the rim as already described with respect to the lower or inner base laminate and an outer fiber-reinforced polymer layer, having a fiber direction, which extends largely in the axial direction. Furthermore, it is also possible in addition or instead of the base laminate with axial fiber direction to provide an inner or outer layer of base laminate with predominantly or exclusively radially oriented fibers or other layer combinations. Schematically represented is finally an outer conclusion of the rim formed by a wheel 10, which will not be discussed further at this point.

Fig. 2 shows again schematically in section a portion of the rim cross-section of Fig. 1 between the shoulder 5 and the rim flange 7. When winding the individual rotating belts 19, for example in the region of the rim flange 7, the width of the individual bands is wider chosen as the effective width of the rim flange. As a result, laterally in the region of the gradation, the band ends 31 are bent or corrugated during the subsequent pressing process of the preform to the rim. The same phenomenon also occurs in the case of the individual band layers 16 in the region of the gradation to the shoulder 5, in that here too the bandwidth for angles is chosen to be wider than the effective width of the step. This also results in a lateral bending of the individual bands. Alternatively, the width of the individual bands may be selected to be narrower if, at the same time, the stack height is further increased relative to the height in the section of the finished pressed rim.

In addition, the thickness of the individual bands as shown in Fig. 3 is shown schematically using a single band 41 shown thicker than the thickness of the resulting after pressing the rim strip. In Fig. 3, the tape thickness is shown schematically compressed with the reference numeral 43th

Another possibility when winding the bands in a portion of the preform of the rim is shown schematically in section on the basis of the rim base 2. Fig. 4 shows that a plurality of bands 15 are arranged side by side to fill the width of the rim base 2 in the entire width. This results in various interfaces or overlaps 16 and 18, as again shown schematically and for example in Fig. 4. It is important, however, that these interfaces do not lie one above the other or next to one another but, for example, as shown clearly in FIG. 4, are formed laterally offset from one another. But it is also possible that overlap the various juxtaposed tape layers per section in some areas and thus no effective interface is formed, as shown in Fig. 4.

However, this structure is usually useful only if the bandwidth is the same, so that two or more different winding steps are not required, which would extend the production time, of course. The goal is yes, with as much bandwidth as possible.

Finally, FIG. 5 schematically shows the manner in which the individual band layers are unwound onto the preforming tool 57 on the rim reformer 59 arranged thereon. The unwound from a drum 51 belt 53 is briefly stopped and cut by means of a cutting tool 61, as shown schematically in Fig. 5a.

Subsequently, as shown in FIG. 5 b shows one half of the tape 53 over the end of the previously cut tape 53 is pushed and connected by means of a Punktschweissgerätes 63 such as an ultrasonic welder to form a welding point 65 to the other end.

Finally, as shown schematically again in Fig. 5c, the newly joined band 53 is moved with the weld 67 against the Felgenpreform 59 to be unwound to form the extending in the circumferential direction band layers, or band stacks.

The joining of the overlapping band ends can of course be done in different ways such as by means of ultrasonic welding or welding with heating element (hot tip, hot edge), etc.

When placing the various tape layers to produce the Felgenpreforms, it is also advantageous if from time to time so-called welding points are set so that the tape layers during the winding process can not move laterally. Of course, these welding points to be set depend on the type of tapes, such as bandwidths, number of tape layers, etc., etc.

On the choice of the materials to be used will not be discussed further here, since both the choice of fiber, the fiber architecture, the matrix polymer, etc. are based on the requirements of the rim to be manufactured and in the following suitable fiber-reinforced polymer semi-finished is well known , such as based on carbon fibers and an amorphous thermoplastic polymer having excellent thermal and mechanical properties, such as Polyetherimide (PET) as a matrix polymer.

Claims (19)

1. A method for producing a vehicle rim of fiber-reinforced polymer material, characterized in that in the manufacture of the preform of the rim inside or outside at least one over the entire rim surface extending base laminate layer of fiber-reinforced polymer semi-finished product or extending over the entire rim surface base laminate layers of fiber-reinforced polymer semi-finished, at least in the range of gradations in the rim contour as between rim base and rim shoulder and / or shoulder to rim flange several stored in the circumferential direction of the rim stacked band layers of fiber-reinforced polymer material are stored or inserted. 2. The method according to claim 1, characterized in that the stacked in the circumferential direction of the rim surface extending band layers are arranged in addition to gradations in the area of the rim flange and the rim shoulder. 3. The method according to any one of claims 1 and 2, characterized in that over the entire circumferential direction of the rim extending in the circumferential direction of the rim band layers distributed over the entire tread of the rim between an inner multilayer preformed base laminate of fiber-reinforced polymer semi-finished and an outer multilayer preformed Base laminate can be arranged from fiber-reinforced polymer semi-finished product. 4. The method according to any one of claims 1 and 2, characterized in that distributed over the entire circumferential direction of the rim extending in the circumferential direction of the rim band layers are arranged directly on and over the entire peripheral surface of a preform and then an outer multi-layer preformed base laminate Fiber-reinforced polymer semi-finished product is arranged. 5. The method according to any one of claims 1 to 4, characterized in that the extending in the circumferential direction band layers during insertion prior to compression to the rim have a greater width than that for the insertion of these band layers respectively provided portion of the rim such as at least 2% wider , 6. The method according to any one of claims 1 to 5, characterized in that the number of extending in the circumferential direction of the rim band layers is greater than what is necessary for the production of the pressed rim, which is preferably at least a 2% higher stack thickness compared to the thickness of finished pressed rim results. 7. The method according to any one of claims 1 to 6, characterized in that the band layers are formed by endless belts, wherein the endless belt is cut at winding for generating the Felgenpreforms at certain intervals such as at a length approximately corresponding to a circumferential length, wherein after cutting Subsequently, the two resulting ends are arranged overlapping and be connected by suitable means such as welding firmly together to form a band ring to then continue to wind the endless belt to produce the next band layer or the next band ring on the rim. 8. The method according to claim 7, characterized in that the overlapping fixedly connected ends of successive band rings are offset from one another in the circumferential direction. 9. The method according to any one of claims 7 or 8, characterized in that the overlapping fixedly connected ends, two juxtaposed band rings are offset from one another in the circumferential direction. 10. The method according to any one of claims 1 to 9, characterized in that when winding the superimposed extending circumferentially band layers from time to time welding points are generated to prevent lateral slippage of the individual band layers during unwinding. 11. The method according to any one of claims 1 to 10, characterized in that on the different sections of the outer rim contour band stacks are unwound with a different number in the circumferential direction extending band layers. 12. The method according to any one of claims 1 to 11, characterized in that ribbon stacks of different thickness are arranged one above the other. 13. The method according to any one of claims 1 to 12, characterized in that a resting directly on a preform tool innermost layer of the multilayer base laminate has a fiber direction, which is formed at least to a large extent in the axial direction. 14. The method according to any one of claims 1 to 13, characterized in that arranged in a resting on the preforming tool multilayer base laminate at least two layers of fiber-reinforced polymer material with a fiber direction at least to a large extent approximately between + 30 ° and + 60 ° with respect the circumferential direction of the rim and at least to a large extent at least approximately between -30 ° and -60 ° with respect to the circumferential direction of the rim. 15. The method according to any one of claims 1 to 14, characterized in that in one outer multilayer base laminate of fiber-reinforced polymer semi-finished one or more layers are formed with a fiber orientation of at least about + 45 °, preferably 60 ° with respect to the circumferential direction and / or ca . -45 °, preferably 60 ° with respect to the circumferential direction of the rim and an outermost layer having a fiber direction of substantially axial alignment. 16. The method according to any one of claims 1 to 15, characterized in that the rim preform is pressed in a corresponding pressing tool to form a rim. 17. Rim made of fiber-reinforced polymer material, characterized in that inside or outside at least one multilayer base laminate of fiber-reinforced polymer semi-finished or between an inner and an outer multilayer base laminate of fiber-reinforced polymer semi-finished several circumferentially extending band stacks are made of fiber-reinforced polymer material. 18. Rim according to claim 17, characterized in that in each case in the contour of the rim running surface circumferentially extending band layers are arranged, wherein the individual band layers have bandwidths which correspond approximately to the thickness of the respective rim portion or at least single or all bands the individual band layers have a greater width. 19. Rim according to one of claims 17 or 18, characterized in that the rim is manufactured by means of a method according to one of claims 1 to 16.