METHOD OF MANUFACTURING TUBULAR HOLLOW PROFILE VEHICLE FRAME PARTS

Abstract

A method for manufacturing a hollow vehicle frame part includes: removing material from a first side of a first billet, creating a first inner shape of a target vehicle frame; removing material from a first side of a second billet to create a second inner shape of a target vehicle frame; bonding the billets together at the faying surfaces on first sides of the billets so the inner shapes face each other; and removing material by machining from the second sides of the first and second billets to create target outer shape of the vehicle frame part. The method further includes forming additional faying surfaces adjacent and at an angle to the faying surfaces on the first sides of the first and second billets, which faying surfaces together form a rabbet-type joint where the first billet and second billet are bonded. A corresponding us vehicle frame is also disclosed.

Claims

1. A method for manufacturing a hollow vehicle frame part comprising removing material from a first side of a first billet to create a first inner shape of a target vehicle frame and wherein material is removed from the first side of said first billet such that at least one substantially flat faying surface is left on said first side of said first billet adjacent to the first inner shape, removing material from a first side of a second billet to create a second inner shape of a target vehicle frame and wherein material is removed from the first side of said second billet such that at least one substantially flat faying surface is left on said first side of said second billet adjacent to the second inner shape, bonding the first billet and the second billet together at the faying surfaces on first sides of the first billet and second billet such that the first inner shape and second inner shape face each other, wherein after bonding, removing material by machining from the second side of the first billet and from the second side of the second billet to create target outer shape of the vehicle frame part, and further in wherein before bonding forming additional faying surfaces adjacent and at an angle to the faying surfaces on the first sides of the first billet and second billet, which faying surfaces together form a rabbet-type joint at which the first billet and second billet are bonded.

2. The method of claim 1, wherein material is removed from the first sides of the first billet and second billet such that an amount of material remains in the second sides of the first billet and second billet before bonding and removing material from the second sides of the first billet and second billet.

3. The method of claim 1, wherein material is removed from the first sides of the first billet and second billet such that an amount of material remains outside of the faying surfaces on the first sides of the first billet and second billet before bonding and removing material from the second sides of the first billet and second billet.

4. The method of claim 1, wherein material is removed from the first sides and second sides of the first billet and second billet such that the target shape of the vehicle frame part has a wall thickness of 0.1-8 mm.

5. The method of claim 1, wherein material is removed from the first sides and second sides of the first billet and second billet such that the target shape of the vehicle frame part has a wall thickness of approximately 1 millimeter.

6. The method of claim 1, wherein at or after bonding the combined block of the first billet and the second billet is attached to a jig for machining any of the second sides of the first billet and second billet.

7. The method of claim 1, wherein the first billet and/or second billet are pre-formed by cold-forging or printing to form a first inner shape and/or second inner shape, after which the first inner shape and/or second inner shape are machined.

8. The method of claim 1, wherein the first side of the first billet and/or the first side second billet are shot-peened after forming the inner shapes.

9. The method of claim 1, wherein the first inner shape and/or second inner shape surfaces are treated by coating, anodizing, coloring or passivating.

10. The method of claim 1, wherein mechanical fastening means through the first billet and second billet at non-machined parts of the first billet and second billet are used for setting and holding the first billet and second billet in relation to each other for bonding.

11. The method of claim 1, wherein mechanical fastening means are used to fasten any of the billets to a jig for machining.

12. The method of claim 1, wherein xyz-coordinate zero points and their relation to one or more sides of a billet and inner shape geometry are determined for each inner shape at or after forming each inner shape.

13. The method of claim 1, wherein the billets are aluminum alloy billets.

14. The method of claim 1, comprising one or more of third, fourth, fifth . . . billets wherein removing material from a first side of a third, fourth, fifth or such billet, which first side is substantially flat, to create third, fourth, fifth or such, inner shape of a target vehicle frame and wherein material is removed from the first side of said third, fourth, fifth or such, billet such that at least one faying surface is left on said first side of said third, fourth, fifth or such, billet adjacent to the third, fourth, fifth or such, inner shape.

15. (canceled)

16. A bicycle frame part manufactured by the method of claim 1.

17. The method of claim 2, wherein at or after bonding the combined block of the first billet and the second billet is attached to a jig for machining any of the second sides of the first billet and second billet.

18. The method of claim 3, wherein at or after bonding the combined block of the first billet and the second billet is attached to a jig for machining any of the second sides of the first billet and second billet.

19. The method of claim 4, wherein at or after bonding the combined block of the first billet and the second billet is attached to a jig for machining any of the second sides of the first billet and second billet.

20. The method of claim 5, wherein at or after bonding the combined block of the first billet and the second billet is attached to a jig for machining any of the second sides of the first billet and second billet.

21. The method of claim 2, wherein the first billet and/or second billet are pre-formed by cold-forging or printing to form a first inner shape and/or second inner shape, after which the first inner shape and/or second inner shape are machined.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Some exemplary embodiments of the present invention are reviewed more closely with reference to the attached drawings, wherein

[0034] FIG. 1 illustrates the machined first billet in accordance with an embodiment of the present invention,

[0035] FIG. 2 illustrates the machined second billet in accordance with an embodiment of the present invention,

[0036] FIGS. 3a and 3b illustrate axonometric and partial cutaway views respectively of the first and second billets combined together in accordance with an embodiment of the present invention,

[0037] FIG. 4 illustrates the bonded first and second billet wherein the second side of the first billet has been machined in accordance with an embodiment of the present invention,

[0038] FIG. 5 illustrates the bonded first and second billet connected to a jig after the second side of the first billet has been machined in accordance with an embodiment of the present invention,

[0039] FIG. 6 illustrates a vehicle frame part product connected to a jig after the second side of the second billet has been machined in accordance with an embodiment of the present invention,

[0040] FIG. 7 illustrates a cutaway drawing of a bicycle frame manufactured by the method in accordance with the present invention,

[0041] FIG. 8 illustrates a cutaway drawing of a bicycle frame part product manufactured by the method in accordance with the present invention, and

[0042] FIG. 9 depicts a flow diagram illustrating an embodiment of the method in accordance with the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] FIG. 1 illustrates the first billet (102a) after machining of the first inner shape (106a). For the present method, the plate-like first billet (102a) is first pre-formed by machining a first side (104a) to create the hollow inner shape of a first elongated hollow frame half constituting a first inner shape (106a). The shape may be determined in view of the target vehicle frame part profile and dimensions. The inner shape is machined to the first billet (102a) such that one or more surfaces are left as faying surfaces whereat the first billet (102a) may be bonded with a second billet (102b). In this embodiment, a rabbet-type joint rim (110a), comprising two faying surfaces at an angle to each other, is formed to the outer rim of the first inner shape (106a) which may be mated with a matching shoulder shape. The first side (104a) surface may be pre-formed or machined substantially flat or to such other shape that it may be set surface to surface with the first side (104b) of the second billet (102b) at least at the faying surfaces whereat the first billet (102a) and second billet (102b) are bonded. Boring holes (112) (only one numbered as an example) of such mechanical fastening means may be formed through the first billet (102a) at the peripheries of the billet, i.e. at the areas that don't coincide or situate too close to the first inner shape (106a) at which boring holes (112) the first billet (102a) may be attached to a jig (114) for machining.

[0044] FIG. 2 illustrates a machined second billet (102b). For the present method, the plate-like second billet (102b) is first pre-formed by machining a first side (104b) to create the hollow inner shape of a second elongated hollow frame half constituting a second inner shape (106a). The shape may be determined in view of the target vehicle frame part profile and dimensions, and in view of the dimensions of the inner shape and/or faying surfaces of the first billet (102a). The inner shape is machined to the second billet (102b) such that one or more surfaces are left as faying surfaces whereat the second billet (102b) may be bonded with the first billet (102a). In this embodiment, a rabbet-type joint shoulder (110b), comprising two faying surfaces at an angle to each other, is formed to the edges of the second inner shape (106b) which may be mated with a matching rabbet-type joint rim (110a) of the first inner shape (106a). The first side (104b) surface may be pre-formed or machined substantially flat or to such other shape that it may be set surface to surface with the first side (104a) of the first billet (102a) at least at the faying surfaces whereat the first billet (102a) and second billet (102b) are bonded. Boring holes (112) may be formed through the second billet (102b) at the peripheries of the billet, i.e. at the areas that don't coincide or situate too close to the second inner shape (106b) at which boring holes (112) the second billet (102b) may be attached to a jig (114) for machining The boring holes (112) of both the first billet (102a) and second billet (102b) may be formed such that holes (112) coincide when the inner shapes (106a, 106b) of the billets (102a, 102b) are set to face each other.

[0045] The first billet (102a) and second billet (102b) comprise a material that may be machined comprising for example metal or metal alloy. Some feasible examples include aluminum alloys 6061-T6, 7005-T6 and 7075-T6. The billets (102a, 102b) may be plate-like, cuboid, cylindrical shape, or some other shaped block of solid material of any sufficient shape, thickness, dimensions and surface shapes. The billets (102a, 102b) may also be parts that are printed with optimal pre-formation. The faying surfaces are preferably machined or they may be otherwise pre-formed as a rabbet-type joint (110ab) defined by the first inner shape (106a) and the second inner shape (106b) set against each other and optionally additionally a number of surfaces on first side (104a, 104b) on either billet (102a, 102b).

[0046] Pre-forming may be used to treat the billets (102a, 102b) before machining For example, cold-forging and casting may be used to shape and treat the billets (102a, 102b), which may be used to reduce the amount of machining needed or to treat the material. Also, techniques may be used to treat the first side (104a, 104b) surfaces and the inner shape surfaces after removal of material. Such techniques include shot-peening, coloring, anodization, passivation and coating, such as Aluminum Oxide Coating, and the like corrosion resistance treatment techniques. Such treatment techniques may be very harsh since the outer surface of the target frame part hasn't yet been formed. This additionally means that inner shape surfaces may be treated independently and from the frame part outer surfaces.

[0047] A CNC (computer numerical control) machining device is preferably used for the machining operations but also other such machining techniques may be used as feasible in view of e.g. engineering tolerance requirements. However, also other machining means, such as manual machining means may be possible in limitations of the required accuracy and tolerances of the target design requirements. Machining is preferably used to remove substance material from the billets (102a, 102b) as well as any residue from the bonding seams, such as removing any bonding material extruding from the profile or outer wall of the target part that is being manufactured.

[0048] FIGS. 3a and 3b illustrate axonometric and partial cutaway aspects respectively of the first billet (102a) and second billet (102b) combined together. The first billet (102a) and second billet (102b) are joined together by bonding the first billet (102a) and the second billet (102b) together at the faying surfaces on first sides (104a, 104b) of the first billet (102a) and second billet (102b) such that the first inner shape (106a) and second inner shape (106b) face each other. Preferably an amount of material remains in the second sides (108a, 108b) of the first billet (102a) and second billet (102b) before bonding and removing material from the second sides (108a, 108b) of the first billet (102a) and second billet (102b) as illustrated. Preferably also an amount of material remains outside of the faying surfaces on the first sides (104a, 104b) of the first billet (102a) and second billet (102b) before bonding and removing material from the second sides (108a, 108b) of the first billet (102a) and second billet (102b) as illustrated. Because the billets (102a, 102b) have more material than the final target vehicle frame part shape the billets (102a, 102b) may be compressed together from various preferred points and the amount of material helps to stiffen the structure while bonding. This also helps to reduce movement and vibration of the structure while machined from the seams and the second sides (108a, 108b) of the first billet (102a) and second billet (102b).

[0049] As illustrated and meant herein throughout, the second sides (108a, 108b) of the billets comprise the all one or more outer sides of the billets, which sides are not the first sides (104a, 104b) at which the billets are bonded together. Because billets may have different geometries the second sides (108a, 108b) are to be understood as to cover all the outer surfaces of the billets, which are machined to create target outer shape of the vehicle frame part.

[0050] The billets (102a, 102b) may be compressed against each other by boring holes (112) through the billets (102a, 102b) at the peripheries of the billets (102a, 102b), i.e. at the areas that don't coincide or situate too close to the inner shapes of the billets (102a, 102b). Via the holes (112) the billets (102a, 102b) may be both compressed against each other and fastened to a jig (114) for machining Alternatively or additionally, clamping means may be used. The mechanical fastening means and/or clamping means may be used to compress and hold the billets (102a, 102b) against each other while the bonding adhesive sets and cures.

[0051] For bonding, two-component adhesives, heat-activated adhesives and the like may be used. The adhesive may be applied to and along the corner of the shoulder (110b) of the rabbet-type joint (110ab) such that when the other billet is pressed against the shoulder (110b) of the other billet the adhesive is squeezed and spread along the different-facing surfaces of the shoulder (110b) and hence adhesive spreads into the two different surfaces of the shoulder (110b) and its opposing surfaces of the rim (110a) of the rabbet-type joint (110ab). Alternatively or additionally, the adhesive may be applied directly on all faying surfaces.

[0052] FIG. 4 illustrates the bonded first and second billet (102b) wherein the second side (108a) of the first billet (102a) has been machined. The structure formed by the bonded billets (102a, 102b) may be attached to a jig (114) and the second side (108a) of the first billet (102a) is machined to create one target outer shape of the vehicle frame part. As illustrated, the boring holes (112) surrounded by a wall remaining billet material housing the mechanical fastening means may be left protruding.

[0053] FIGS. 5 illustrates the bonded first and second billet (102b) connected to a jig (114) after the second side (108a) of the first billet (102a) has been machined. Herein the second side (108b) of the second billet (102b) is machined to create a second target outer shape and essentially finalize the target shape of the vehicle frame part. Logos and other details such as connection points for links, bearings, load-bearing structures, derailleurs, seat posts, forks, brakes, hubs, bottle holders, and the like, as well as attachment means, such as screws and the like.

[0054] FIG. 6 illustrates a vehicle frame part (100) product connected to a jig (114) after the second side (108b) of the second billet (102b) has been machined. The final product may be machined and finished to remove any protruding adhesives or billet material. As depicted, the vehicle frame part (100) attained with the method includes a hollow profile, which may be also tubular and have a substantially thin wall thickness, which wall thickness may be also variable along the frame part (100). The various shapes may include linear and curvilinear shapes via the longitudinal and vertical directions of the frame part (100) to attain various different kinds of shapes and surface textures and structures, such as protrusions, recesses, through holes, means for attaching components, and other such mechanical details.

[0055] FIG. 7 illustrates a cutaway drawing of a bicycle frame manufactured by the method. The bicycle frame shown here is the front frame of a bicycle. The wall-thickness may vary, even along the profile, and some examples of suitable wall-thickness comprise thicknesses from the range of 0.1-8 mm. One preferable wall-thickness is approximately 1 mm. However, the wall-thickness may be chosen in view of billet material, frame part geometry and frame part purpose.

[0056] FIG. 8 illustrates a cutaway drawing of a bicycle frame part product manufactured by the method. The rabbet-type joint (110ab) whereat the billets (102a, 102b) are joined comprises a shoulder (110b) at the second billet (102b) to which the rim (110a) of the first billet (102a) is set for bonding. The frame part may also comprise a portion with a higher wall-thickness at the location of the rabbet-type joint (110ab), which portion may protrude from the overall frame part profile as illustrated. However, due to the bonding connection being a rabbet-type joint (110ab) the outer profile may be machined to a smooth and continuous curvilinear profile allowing for a plurality of different frame part shapes. The rabbet-type joint (110ab) provides a wide surface for the bonding adhesives and due to the shape also strength into various directions of the bonding connection.

[0057] FIG. 9 depicts a flow diagram illustrating an embodiment of the method (200) in accordance with the present invention.

[0058] At 202, referred to as the start-up billets may be fastened to a jig for machining

[0059] At 204, the material is removed from a first side of a first billet to create a first inner shape of a target vehicle frame and wherein material is removed from the first side of said first billet such that at least one faying surface is left on said first side of said first billet adjacent to the first inner shape. Also, a first geometry for a rabbet-type joint is formed to or adjacent to the first inner shape. The first side may be machined or otherwise pre-formed to be substantially flat for being able to set another substantially flat surface against it. As step 205, pre-forming or post-forming of the first inner shape and/or other parts of the first side may be carried out before, at or after creating the first inner shape. Also, the billet may be determined and assigned xyz-coordinate zero points and their relation to one or more sides of the billet in view of the formed inner shape geometry of the billet.

[0060] At 206, the material is removed from a first side of a second billet to create a second inner shape of a target vehicle frame and wherein material is removed from the first side of said second billet such that at least one faying surface is left on said first side of said second billet adjacent to the second inner shape. Also, a second geometry for a rabbet-type joint is formed to or adjacent to the first inner shape that fits with the first geometry. The first side may be machined or otherwise pre-formed to be substantially flat for being able to set another substantially flat surface against it. As step 207, pre-forming or post-forming of the second inner shape and/or other parts of the first side may be carried out before, at or after creating the second inner shape. Also, the billet may be determined and assigned xyz-coordinate zero points and their relation to one or more sides of the billet in view of the formed inner shape geometry of the billet.

[0061] At 208, a first geometry for a rabbet-type joint is formed to or adjacent to the first inner shape and a second geometry for a rabbet-type joint is formed to or adjacent to the second inner shape that fits with the first geometry. The rabbet-type geometry of the joint and its faying surfaces is preferably done while forming the first inner shape and the second inner shape. The first geometry may be for example a rim with a 90 degree angle corner, which may be mated with a shoulder with a rim or recess of 90 degree angle corner. The two main faying surfaces of the rabbet-type joint are defined by a faying surface at the first side of a billet substantially flat and adjacent to an inner shape and an additional faying surface at, in or protruding from the second inner shape. These faying surfaces are adjacent and at an angle to each other. The shape and geometry, e.g. the area, of the faying surfaces as well as the angle thereof may vary and be chosen in view of design requirements.

[0062] At 210, the first billet and the second billet are placed together at the faying surfaces on first sides of the first and second billets such that the first and second inner shapes face each other. The first and second billets are bonded together such as that their first and second geometries together form a rabbet-type joint wherein at least one surface is used as a faying surface for bonding. Alternatively, both surfaces of the shoulder of the rabbet-type joint may be used as faying surfaces with the corresponding opposing faying surfaces of the rim of the other billet. Because the second sides of the billets haven't yet been machined the billets still have a substantially high amount of mass and thickness when compared to the final target shape of the frame part, which means that high amount of pressure may be used to compress the billets against each other for bonding. This means that more pressure may be used to compress the billets to each other than would be possible for a two ready-machined frame halves. Also, setting and keeping the frame parts in place and in preferred relation to each other is possible because of the sufficiently high pressure that may be used and because of the rabbet-type joint geometry at the seams of the billets.

[0063] At 212, material is removed by machining from the second side of the first billet and from the second side of the second billet to create target outer shape of the vehicle frame part.

[0064] A person skilled in the art will be able to appreciate that some steps may be carried out coincidentally or at different orders. Further, although only two billets are depicted the method allows for use of a further number of billets. One or more of third, fourth, fifth, etc., billets removing material from a first side of the third, fourth, fifth or such billet, which first side is substantially flat, to create third, fourth, fifth or such, inner shape of a target vehicle frame and wherein material is removed from the first side of said third, fourth, fifth or such, billet such that at least one faying surface is left on said first side of said third, fourth, fifth or such, billet adjacent to the third, fourth, fifth or such, inner shape.

[0065] The scope of the invention is determined by the attached claims together with the equivalents thereof The skilled persons will again appreciate the fact that the disclosed embodiments were constructed for illustrative purposes only, and the innovative fulcrum reviewed herein will cover further embodiments, embodiment combinations, variations and equivalents that better suit each particular use case of the invention.