WO2015171638A1

WO2015171638A1 - Blow molded roof rail with anchor plate

Info

Publication number: WO2015171638A1
Application number: PCT/US2015/029283
Authority: WO
Inventors: David Flajnik; Marc-Andre QUELLET; Balwinder Singh; Michael Kurt PROFYT
Original assignee: Salflex Polymers Limited
Priority date: 2014-05-09
Filing date: 2015-05-05
Publication date: 2015-11-12

Abstract

A vehicle roof rail is disclosed that includes an elongate primary body having an outboard wall and an inboard wall. The inboard wall defines one or more attachment points for attachment of a secondary member. Each attachment point is associated with a respective anchor plate having a suitable fastening system for connecting the secondary member thereto. The anchor plate is mechanically locked within the inboard wall of the roof rail.

Description

BLOW MOLDED ROOF RAIL WITH ANCHOR PLATE

Inventors: Marc-Andre Ouellet, Michael Kurt Profyt, Balwinder Singh, David Flajnik Field of the Invention

[0001] The present invention relates to the field of blow molded roof rails, and in particular to the incorporation of an insert-molded anchor plate to enhance attachment of secondary structures thereto.

Background of the Invention

[0002] The automotive roof rail assembly is quickly becoming a sophisticated payload storage/transport system for modern vehicles, in particular for sport-oriented activities. The roof rack assembly is generally comprised of a pair of automotive roof rails, and a variety of transverse secondary members for interconnecting them.

[0003] Historically, automotive roof rails have been of metallic construction, generally steel or aluminum. In more recent years, there has been a shift towards roof rails formed of thermoplastic materials, in large part to address corrosion issues and to achieve lighter-weight systems, generally for fuel savings.

[0004] Thermoplastic roof rails permit greater flexibility with respect to design parameters, enabling nicely contoured profiles and generally enhanced overall aesthetics. But with this focus on form, the need for safe and secure function remains paramount, in particular given the expanded usage of exterior storage systems now available for use on automotive roof rail assemblies. Accordingly, automotive roof rail systems, and in particular the secondary members interconnecting them must be configured to handle significant payload requirements, while accommodating attachment methodologies that compliment modern aesthetics while achieving the required performance characteristics.

Summary of the Invention

[0005] According to an embodiment, provided is a roof rail. The roof rail comprises an elongate primary body having an outboard wall and an inboard wall. The inboard wall defines one or more attachment points for attachment of a secondary member. Each attachment point is associated with a respective anchor plate having a suitable fastening system for connecting the secondary member thereto. The anchor plate is mechanically locked within the inboard wall of the roof rail.

Brief Description of the Drawings

[0006] The foregoing and other features and advantages of the invention will be apparent from the following description of the invention as illustrated in the accompanying drawings. The accompanying drawings, which are incorporated herein and form a part of the specification, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention. The drawings are not to scale.

[0007] Fig. 1 is a perspective view of a blow molded roof rail in accordance with an embodiment hereof.

[0008] Fig. 2 is a partial perspective view of a vehicle having a pair of the blow molded roof rails of Fig. 1.

[0009] Fig. 3a is a partial perspective view showing an insert-molded anchor plate in position on the blow molded roof rail of Fig. 1.

[0010] Fig. 3b is a perspective view of the anchor plate of Fig. 3a, presented in isolation.

[0011] Fig. 4 is a cross-sectional view of an anchor plate in accordance with an embodiment hereof having an internally threaded rivet-type fixture fastening system.

[0012] Fig. 5 is a cross-sectional view of an anchor plate in accordance with an embodiment hereof having a weld-nut fastening system.

[0013] Fig. 6 is a schematic cross-sectional view of a mold tool showing the positional relationship between the formed roof rail and the parting line.

Detailed Description of Embodiments of the Present Invention

[0014] Specific embodiments of the present invention will now be described with reference to the Figures, wherein like reference numbers indicate identical or functionally similar elements. The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. A person skilled in the relevant art will recognize that other configurations and arrangements can be used without departing from the scope of the invention. Although the description and drawings of the embodiments hereof exemplify the technology as applied to automotive roof rails, the invention may also be applied to other applications, for example with thermoplastic articles in general that require additional structural reinforcement at anchorage points. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following detailed description.

[0015] Turning now to Fig. 1, shown is an exemplary roof rail 10 according to an embodiment of the invention. Roof rail 10 is provided in pairs, as shown in Fig. 2, and may cooperate to support contents, for e.g. sports equipment, cargo, placed upon the vehicle roof. Roof rail 10, and in particular where roof rail 10 is provided in pairs, may further cooperate with one or more transverse secondary members 14, i.e., cross-bars, with an exemplary cross bar shown in Fig. 2 at the most forwardly position on roof rail 10, to provide additional structure/support for carrying elongated loads, e.g. hard-case carriers.

[0016] Secondary members 14 are affixed to roof rail 10 by way of threaded fasteners at designated attachment points 18. To enhance structural integrity, each attachment point 18 on roof rail 10 is configured with an insert-molded anchor plate 22. Anchor plate 22 is a separately formed structure that is insert-molded into roof rail 10 during manufacture. As such, and as will be discussed in greater detail below, anchor plate 22 is mechanically locked into the roof rail structure, and serves to mitigate point load forces by distributing forces over a greater span or area of roof rail 10.

[0017] Turning now to Figs. 3a and 3b, shown is anchor plate 22 in location on roof rail 10, including fastening structures, as detailed below, and in isolation therefrom, respectively. Anchor plate 22 is configured with a primary body 26 having a stepped periphery 30. Anchor plate 22 also provides a registration feature 34, i.e., a central cut-out, on primary body 26 configured to receive thermoplastic material on forming roof rail 10, thereby providing additional registration of anchor plate 22 thereto. Other features of anchor plate 22 include at least one aperture 38 for use with a suitable fastening system 42, and in the embodiment shown, angled forward and rearward edges 46, 50.

[0018] Turning now to Fig. 4, shown is a cross-sectional view through line A-A of Fig. 1. Roof rail 10 is a blow-molded hollow structure having an elongate primary body with an outboard wall 54, an inboard wall 58, and an attachment footing 62 along a lower wall section between outboard wall 54 and inboard wall 58. Footing 62 is configured to cooperate, using suitable fasteners (not shown), with the vehicle roof structure, so as to locate roof rail 10 securely thereon. Outboard wall 54 may be provided with design features and an aesthetically pleasing surface, while inboard wall 58 is configured with the aforementioned attachment points 18 for mounting secondary members 14 (not shown). Within roof rail 10, anchor plate 22 is arranged so as to have stepped periphery 30 step inwards in the direction towards inboard wall 58. In this way, anchor plate 22 is mechanically locked from being pulled away from the thermoplastic body of roof rail 10. Stated differently, stepped periphery 30 is configured to provide a footing 66 that is encapsulated within inboard wall 58 of roof rail 10, thereby securing it in place.

[0019] As indicated earlier, anchor plate 22 provides at least one aperture 38 for use with a suitable fastening system 42, an example of which is shown in Fig. 3a. In the embodiment shown in Fig. 4, fastening system 42 includes a threaded receptacle 70 for placement in aperture 38. An exemplary threaded receptacle 70 is an internally threaded rivet-type fixture, such as a Plusnut® blind, threaded fastener, the features of which are known in the industry. As will be noted, this type of fixture presents an additional mechanical lock to secure anchor plate 22 to roof rail 10. During the blow molding process to form roof rail 10, a thermoplastic wall 74 forms over the outboard side of anchor plate 22. On installation of the internally threaded rivet- type fixture in a post-mold operation, tab(s) 78 form over the outboard side of thermoplastic wall 74, thereby creating an additional mechanical lock to secure anchor plate 22 in position on roof rail 10. Threaded receptacle 70 cooperates with a threaded fastener 72 (shown in dash lines in Fig. 4) to secure secondary members 14 (not shown) thereto.

[0020] Fig. 5 presents an alternate embodiment for fastening system 42 having a similar anchor plate on a blow molded roof rail, where anchor plate 22a is fitted with an internally threaded weld-nut fixture 82, the features of which are known in the industry. In contrast to the internally threaded rivet-type fixture of Fig. 4, weld-nut fixture 82 is affixed (i.e. welded) to the outboard side of anchor plate 22a, coaxial with aperture 38 prior to blow molding. As such, during the blow molding process, thermoplastic wall 74a that forms over the outboard side of anchor plate 22a extends into an undercut 86 situated within a base of a body 90 of weld-nut fixture 82. As a result, body 90 of weld-nut fixture 82 is dimensionally stable and prevented from pulling through thermoplastic wall 74a, thereby establishing an additional locking element to secure anchor plate 22a in position on roof rail 10. Weld-nut fixture 82 cooperates with a threaded fastener (not shown) to secure a secondary member similar to that detailed above having regard to Fig. 4. [0021] As noted in each of the embodiments illustrated in Figs. 4 and 5, inboard wall 58 exhibits increased material thickness compared to other sections of roof rail 10, in particular having an increased material thickness in a region 59 below anchor plate 22, 22a. This increase of material is intentional, so as to provide greater resistance to rotational movement of anchor plate 22, 22a, for example as would be experienced during vertical pull at the center of the secondary members, i.e., cross-bars. Increased material thickness is achieved by locating this region in the vicinity of the parting line P of mold tool T, as shown in Fig. 6. As is generally known in blow molding processes, at parting line P, additional material may deposit on the cavity side of the mold tool, resulting in increased wall thickness. As additional strength is beneficial in inboard wall 58 at region 59, parting line P is aligned with this region, as shown. On outboard wall 54, parting line P is located at transition 94 between outboard wall 54 and footing 62, where once again additional material is shown to be deposited.

[0022] As different applications for anchor plate 22, 22a may require different load requirements, the present invention contemplates the ability to set the amount of material deposition on the cavity side of parting line P. The extent of material deposition is controlled by setting length L of the pinch-off 98, and through the use of material run-out areas 102. With a lengthened pinch-off 98, more material is displaced during mold closure, resulting in increased material deposition. Where pinch-off 98 is configured to be very short, very little material is displaced, resulting in less material deposition on the cavity side of parting line P.

[0023] As mentioned above, roof rail 10 is manufactured using a blow molding process, with anchor plate 22, 22a being insert-molded into position. In one exemplary process, the anchor plate is pre-loaded into the mold tool prior to introduction of a parison. The anchor plate may be manually pre-loaded, or automatically pre-loaded using a suitable robot and end-of-arm-tooling. The mold tooling will generally be provided with a suitable mechanism to retain the anchor plate in position prior to the blow-molding step. On blow molding, the anchor plate is insert-molded into the molded roof rail, to be mechanically locked in place as detailed above. The molded roof rail is then subject to the required post-mold process, depending on the type of fastener system selected for the application.

[0024] Roof rail 10 may be formed from a range of materials including, but not limited to, polypropylene, thermoplastic polyolefms (TPO), acrylonitrate-butadiene-styrene (ABS), polycarbonate (PC), polybutadiene terephthalate (PBT), polyethylene terephthalate (PET), nylon, polyvinyl chloride (PVC), polystyrene (PS), polyethylene (PPE), and blends of the above materials with other suitable materials, e.g., fillers including, but not limited to glass fibres, talc, etc.. In one particular embodiment, the roof rail is constructed using polypropylene containing 15% glass filled material.

[0025] Anchor plate 22, 22a may be a metallic or non-metallic structure. Suitable metallic materials may include metal alloys, while non-metallic materials may include polymers and polymer-based composites, with or without material additives such as glass-fiber, carbon fiber, etc., as well as glass-filled component technologies.

[0026] While anchor plate 22, 22a has been exemplified as having two attachment points, namely in the vicinity of each terminal end, in some applications additional attachment points may be implemented. For example, in some applications, it may be advantageous to incorporate an additional attachment point at one or more intermediate positions along anchor plate 22, 22a.

[0027] It will be appreciated that a variety of configurations may be implemented for anchor plate 22, 22a, depending on the intended application. The typical size of anchor plate 22, 22a intended for use in roof rail applications is 1" wide by up to 6" in length, but anchor plates may be larger/smaller in either (or both) dimensions, depending on the static and dynamic load requirements specified by OEMs for the designated attachment points. The thickness of the anchor plate 22. 22a may be anywhere from 1 mm to 4 mm as required, but once again, thickness dimensions both greater or less than this range may be implemented where necessary.

[0028] It should be noted that in the description, terms such as forward, front and derivations of these terms are intended to mean or refer to an orientation directed towards, or a location situated towards the front of the vehicle. Similarly, terms such as rearward, rear and derivations of these terms are intended to mean or refer to an orientation directed towards, or a location situated towards the back of the vehicle. The term outboard is intended to mean or refer to an orientation directed towards, or a location situated outwardly from the side of the vehicle. The term inboard is intended to mean or refer to an orientation directed towards, or a location situated towards the longitudinal centerline of the vehicle.

[0029] While various embodiments according to the present invention have been described above, it should be understood that they have been presented by way of illustration and example only, and not limitation. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the scope of the invention. Thus, the breadth and scope of the present invention should not be limited by any of the above-descried exemplary embodiments, but should be defined only in accordance with the appended claims and their equivalents. It will also be understood that each feature of each embodiment discussed herein, and of each reference cited herein, can be used in combination with the features of any other combination. All patents and publications discussed herein are incorporated by reference herein in their entirety.

Claims

CLAIMS What is claimed is:

1. A thermoplastic roof rail comprising,

an elongate primary body having an outboard wall and an inboard wall, the inboard wall defining one or more attachment points for attachment of a secondary member,

wherein each of the one or more attachment points is associated with a respective anchor plate having a fastening system for connecting the secondary member thereto, and

wherein the anchor plate is mechanically locked with the inboard wall of the elongate primary body.

2. The thermoplastic roof rail of claim 1, wherein the anchor plate provides a stepped periphery defining a footing for encapsulation within the inboard wall of the roof rail.

3. The thermoplastic roof rail of claim 1, wherein the anchor plate provides a registration feature configured to receive thermoplastic material on forming the roof rail.

4. The thermoplastic roof rail of claim 3, wherein the registration feature is provided in the form of a central cut-out.

5. The thermoplastic roof rail of claim 1, wherein the anchor plate includes at least one aperture for cooperation with the fastening system.

6. The thermoplastic roof rail of claim 5, wherein the fastening system is an internally threaded rivet-type fixture positioned within the aperture, the internally threaded rivet-type fixture being configured to cooperate with a threaded fastener for securing the secondary member thereto.

7. The thermoplastic roof rail of claim 5, wherein the fastening system is a weld-nut fixture affixed to an outboard side of the anchor plate coaxial with the aperture, the weld-nut fixture being configured to cooperate with a threaded fastener for securing the secondary member thereto.

8. The thermoplastic roof rail of claim 1, wherein the inboard wall provides increased material thickness relative to the outboard wall.

9. The thermoplastic roof rail of claim 8, wherein the increased material thickness is most pronounced in a region below the anchor plate.

10. The thermoplastic roof rail of claim 1, further comprising:

a footing along a lower wall section between the inboard and outboard walls.

11. The thermoplastic roof rail of claim 1 , wherein a transition between the outboard wall and the footing is provided with increased material thickness relative to the outboard wall.

12. The thermoplastic roof rail of claim 1 , wherein the primary body is blow molded.

13. The thermoplastic roof rail of claim 1, wherein the primary body is made of

polypropylene, thermoplastic polyolefms, acrylonitrate-butadiene-styrene, polycarbonate, polybutadiene terephthalate, polyethylene terephthalate, nylon, polyvinyl chloride, polystyrene, polyethylene, or a combination thereof.

14. The thermoplastic roof rail of claim 13, wherein the thermoplastic forming the primary body further includes material additives such as glass fiber or talc.

15. The thermoplastic roof rail of claim 1, wherein the anchor plate is made of a metallic material.

16. The thermoplastic roof rail of claim 15, wherein the metallic material is a metal alloy.

17. The thermoplastic roof rail of claim 1, wherein the anchor plate is made of a non-metallic material.

18. The thermoplastic roof rail of claim 17, wherein the non-metallic material is a polymer, a polymer-based composite, or a polymer-based composite with material additives.