WO1997018098A1

WO1997018098A1 - Improvement to a plastic wheel rim and/or wheel

Info

Publication number: WO1997018098A1
Application number: PCT/FR1995/001506
Authority: WO
Inventors: Alexandre Guichard; Gérard Legerot; Roger Philibert
Original assignee: Bird
Priority date: 1995-11-15
Filing date: 1995-11-15
Publication date: 1997-05-22

Abstract

A rim for a wheel with small or large spokes for use on a cycle, a trailer, a wheelchair or the like. The rim is made of a reinforced thermally injection mouldable plastic and comprises two decorative flanges (20) and two structural members (1) each consisting of an outer circular ring (2) secured to an inner circular ring (3) via connecting bridges (7).

Description

IMPROVEMENT FOR 1 YEAR AND / OR WHEEL IN PLASTIC MATERIAL

The present invention relates to a wheel rim with spokes or spokes made of plastic material, composed of structural frames, decorative flanges, and more particularly a wheel rim made of light weight plastic material, of high mechanical resistance, provided with flanges. interchangeable exteriors, simple assembly and can be produced in industrial manufacturing conditions at very low cost price.

The invention relates more particularly to improvements in the design and assembly of rims in heat-injectable plastic, for which the optimizations relate to weight savings and cost reductions.

The wheel rims in thermo-injectable plastic are traditionally of the so-called monobloc design and manufactured from a single injection mold. Such designs imply that the side walls constituting the external shape also assume the structure function subjected to the major part of mechanical and atmospheric stresses. For this, the material used must meet the difficult to achieve compromise combining very good intrinsic mechanical characteristics in bending, torsion and fatigue, excellent resistance to dynamic shocks, good resistance to atmospheric agents, while retaining a good appearance. of surface capable of accepting resumptions of decorations carried out hot, likely to generate post-deformations.

To withstand very high mechanical stresses under conditions of use, the intrinsic mechanical characteristics of the material must be associated with significant moments of inertia, therefore significant wall thicknesses penalizing the weight, the cooling time of molding and therefore the cost. Furthermore, the rims intended to receive tires have retaining undercuts at the level of the contact profile of the rims and tires. To produce these undercuts, the injection molds must be fitted with removable mold release trolleys, this considerably complicating the mold technology and thus increasing their cost. The cost price of the parts produced from these molds is also penalized since additional kinematic movements compared to a natural release increase the production cycle time.

The rim according to the invention overcomes these drawbacks. It comprises, in fact, two assembled internal structural structures, consisting of an outer ring, an inner ring and connecting bridges provided with latching windows, the whole forming a framework supporting the mechanical stresses, while on these two frame structures are attached two decorative flanges.

Thus, the wheel rim according to the invention is made of reinforced thermo-injectable plastic, and is characterized in that it comprises two decorative flanges and two structural frames each consisting of a circular outer ring secured by bridges connecting a circular inner crown.

According to additional characteristics, the structural structures are assembled by hot rolling of cylindrical or conical pins, through cylindrical or conical holes, or by screwing, by riveting, or even by bonding or welding.

According to other characteristics, the composition of the materials used for the structural frames comprises from 0.1% to 40% of a load of carbon fibers, of length between 0.1 mm and 10 mm, or of a mineral isotopic filler, or a ceramic filler, or a glass fiber filler between 0.1 mm and 10 mm in length, or an anti-shrinkage blowing agent, or a protective agent against ultraviolet rays, or their mixture, while the material composing the decoration flanges is chosen from Acrylonitrile-Butadiene-Styrene (ABS) resins, or from Polystyrene-Acrylonitrile (SAN) resins.

According to a preferred arrangement, the decoration flanges are formed of a circular crown whose distance between the outside diameter and the inside diameter is between 10 mm and 100 mm, and whose thickness is between 0.5 mm and 8 mm, while they include snap pins tangent to the outside diameter of the flanges of rectangular or circular section, which can be provided with one or more stiffening fin (s), and having an increase in thickness at their free end of triangular or partially circular section.

Furthermore, the decoration flanges advantageously comprise on their internal diameter thickness increases in the form of beads of partially circular or partially polylinear section, tangent and concentric with the internal diameter of the flanges.

In addition, the inner crown of the structural frames has chamfer segments or spoke segments on the smallest diameter of the crown, while the connecting bridges of the frame structures have snap-in windows and the crown outer and inner crown of the structure frames are aligned or offset axially by a distance between 0 and 80 mm.

Let’s add that, advantageously, the connecting bridges of the structural frames form two by two in the radial plane of the rim angles between 0 ° and 90 ° inclusive, and each have their length and in the axial plane of the rim an angle between 90 ° and 180 ° inclusive.

It should also be noted that the visible surfaces of the decoration flanges after snap-fastening are in the form of convex or concave envelopes and ensure good aesthetics of the product as well as good aerodynamics. Other characteristics and advantages of the invention will emerge from the description which follows with reference to the appended drawings which are given only by way of nonlimiting examples.

Figure 1 shows, in section, the rim assembled according to the invention.

Figure 2 shows, in front view, a structural frame.

Figures 3a and 3b are partial sections along AA of the outer ring.

FIG. 3a shows it for use with a conventional tire.

FIG. 3b shows it for use with a tire of the tubular type.

Figure 4 is a view, in partial section along BB, of the inner ring.

Figure 5 is a sectional view of a structural frame.

Figure 5a is a view similar to Figure 5 showing an alternative embodiment in which the connecting bridges are offset.

Figures 6a, 6b, 6c, 6d and 6e are views, in section along CC, of the different possible profiles for the connecting bridges.

Figure 7 is a partial front view of the rim illustrating a possible embodiment of the connecting bridges.

Figure 8a is a view similar to Figure 7 showing an alternative embodiment.

Figures 9, 10 and 11 are views similar to Figure 7 showing three alternative embodiments.

Figures 12, 13 and 14a to 14e show the click-in windows and their possible shapes. Figure 12 is a partial front view.

Figure 13 is a sectional view along DD.

Figures 14a to 14e illustrate possible shapes of latching windows.

Figures 15 and 16 are views similar to Figure 5, showing more particularly the holes and the pins of the connecting bridges.

Figures 17 and 18 show, in section, the chamfer and the radius of the inner ring in two variants.

Figures 19, 20, 21 and 22 show, in section, the different assemblies of the injection frames on a flange.

FIG. 23 represents, in front view, a decorative flange and its snap pins.

FIG. 24 represents, in section along EE, a decorative flange and its snap-in pins.

Figure 25 is a partial perspective view which shows the injection points on a decoration flange.

Figures 26a, 26b and 26c show, in section, the shapes of the snap pins.

Figures 27a, 27b, 27c and 27d are views, in section along FF, illustrating several possible variants.

Figures 28, 28a, 28b show, in section, the two embodiments of the bead segments of a flange.

With reference to FIGS. 1 to 23, the rim comprises several components made of heat-injectable plastic material including two structural frames (1) and two decorative flanges (20) snapped on and / or glued to said frames. The two structural frames (1) consist of an outer circular crown (2). Concentrically an inner circular crown (3) is integral with the outer crown by means of connecting bridges (7) connecting the inner diameter (5) of the outer crown (2) to the outer diameter (6) of the inner crown ( 3).

In the embodiment according to Figure 3a, the inner profile of the outer ring (2) is intended to receive a tire, and according to Figure 3b, a hose. These interior profiles comply with European standards ETRTS 1991 and following. The passage from one version to another is carried out from the same injection mold by simply changing removable circular sectors of the mold, determined by the right angle between the axes (n) and (m) of Figures 2 and 3, mold sectors whose external profiles correspond either to a profile for tires or to a profile for hoses.

The outer ring (2) and the inner ring (3) concentric and linked by the connecting bridges (7) are positioned relative to each other at a distance which can be between 5 and 120 mm depending on the shapes of different realization.

The number, sizing and cross-sectional shape of the connecting bridges (7) depend mainly on the different levels of quality and nervousness that a wide range of different rims can have. The number of these bridges (7) can be between 20 and 60 bridges, the width (L) of each bridge (7) is between 5 and 35 mm, the sections are chosen from a range of profiles having moments of inertia adapted to the mechanical stresses exerted. Figures 6a, 6b, 6c, 6d and 6e show different forms of possible sections, sections of Figure 6 such as igneous polyl.

The inner circular crowns (3) have a section in section as illustrated in FIG. 4, having an angle (a) of between 10 ° and

180 ° closed by a curved and / or polyline segment (4) and the value of which is determined by the embodiments of spoke rims or spoke rims, functions not illustrated. As illustrated in Figures 5 and 5a, the outer ring (2) and the inner ring (3) can be aligned, that is to say in the same plane P, or axially offset by a distance (h) between 0 and 80 mm inclusive, thus making it possible either to obtain a rim with a so-called wide profile, or to obtain a rim in which the tire or the tubular is axially offset with respect to the central axis of the hub. wheel. For these embodiments of structural frames with offset axial planes, the injection mold comprises cores of interchangeable shapes.

It can be seen, with reference to FIGS. 7 and 8, that the connecting bridges (7) form two by two in the radial plane of the rim, angles (X) of between 0 ° and 90 ° inclusive. A configuration with angles of 0 °, that is to say parallel connecting bridges two by two, is more particularly intended for an embodiment of spoke rim. A configuration with angles between 0 ° and 90 ° is more particularly intended for an embodiment of a rim with sticks, the top of the angle and its opening being a function of the width of the sticks.

During the injection of the plastic material (FIG. 7) into the structural frame mold through the injection points (15), the fronts of molten material (16) progress on both sides to join together at the end of injection in weld lines (17) and (18). A judicious choice of the location of the injection points (15) in the frames, in particular on the connecting bridges (7), makes it possible to locate the weld lines (17) and (18) in the outer rings (2) and interior (3) midway between the connecting bridges (7).

Figures 9, 10 and 11 illustrate different forms of connecting bridges (7) which each have over their length and in the axial plane of the rim an angle (Y) between 90 ° and 180 ° inclusive. The value of the angle depends on the desired torsional stiffness on the rim. According to FIG. 9, the connecting bridge (7) comprises two portions (7a, 7b) forming an angle (X) of 90 °, while, according to FIG. 10, the two portions (7a, 7b) form an angle ( Y) obtuse. In the variant of Figure 11, the connecting bridge (7) has a single straight portion. Note, as it appears in FIGS. 12, 13 and 14, that the connecting bridges (7) have snap-in windows (8) in the thickness of the walls intended to be used for snap-fastening the pins for assembling the flanges of decoration on the frame structures. The snap-in windows (8) can, of course, have different shapes such as, for example, square, rectangular, polygonal, round or ovoid, as illustrated in FIGS. 14a, 14b, 14c, I4d, 14e and I4f.

According to the embodiments according to FIGS. 15 and 16, the connecting bridges (7) each comprise a cylindrical hole (9), and / or a conical hole (10), and / or a cylindrical pin (11), and / or a conical pawn (12). According to different combinations, the structural frames can be assembled by bolting and / or by screwing in the holes (9) and (10), as shown in FIG. 19, and / or by hot rolling of the pins ( 11) and (12), as illustrated in FIG. 20, and / or by bonding the pins (12) as shown in FIG. 21, and / or by riveting (19), as according to the variant in FIG. 22 Of course, the assembly of the structural frames can be achieved by any other means such as for example by bonding or welding of the type by vibrasons or vibrations.

Referring to Figures 17 and 18, the inner ring (3) has on its smallest diameter, chamfer segments (13) and / or radius segments (14) concentric with the inner ring.

These chamfers or these spokes are particularly intended to be used for the snap-fastening of the assembly members of the decoration flanges.

According to a preferred arrangement, the rim comprises decor flanges (20) as illustrated in FIGS. 1, 23 and 24, the decor flanges that can be snapped on and / or bonded to the structural frames are in the form of crowns (20 ) circular whose distance (d) between the outside diameter and the inside diameter is between 10 and 100 mm, and whose thickness (e) is between 0.5 and 8 mm. The external surface (200) visible after snap-fastening on the frame structures is an envelope of curved and / or concave shape, and / or of shape with plane oriented facets. Furthermore, by a judicious choice of the location of the injection points (24) supplied by heated channels (22) and (23), the weld lines of the fronts of molten material at the end of injection into the mold flange are located midway between the snap pins (21) and flanges (20), as shown in Figure 25.

As appears more particularly in FIGS. 1 and 26a, 26b, 26c, the decoration flanges (20) have on the non-visible face after snap-fastening, twenty to sixty snap-in pins (21). These pins are tangent to the outside diameter of the flanges, and can be of square, rectangular, circular or ovoid section and can be provided with one or more stiffening fin (s) (26), as shown in FIGS. 27c and 27d. At the free end of the pins (21), an increase in thickness forming a latching projection (25) of triangular section and / or partially circular makes it possible to ensure the latching after penetration into the windows (8) of the connecting bridges (7) of structural structures. Figures 26a, 26b and 26c illustrate different variants of latching projections.

With reference to FIGS. 28a and 28b, the decoration flanges (20) include thickness increases (27) in the form of tangent and concentric bead segments with the internal diameter of the flanges (20). These segments are of partially circular and / or partially ovoid and / or partially polyline section. When assembling the flanges (20) on the structure frames (1) the cords (27) penetrate and snap into the chamfers (13) or into the spokes (14) of the inner rings (3) of the frames ( 1).

In order to avoid possible taking of mechanical play under the action of vibrations, the pins (21) and / or the cords (27) can be coated with a flexible or rigid adhesive of the two-component type, for example.

The decoration flanges (20) are injection molded with a material chosen from Acrylonitrile-Butadiene-Styrene (ABS) resins, or from Polystyrene-Acrylonitrile (SAN) resins. The materials used to mold the frameworks and / or the flanges include in volume a filler:

- between 5% and 40% of carbon fibers with a length between 0.1 and 10 mm to optimize the flexural modules and the weights;

- and / or isotopic mineral between 0.1% and 50% to homogenize the distribution of the effects caused by mechanical stresses;

- And / or ceramic between 0.1% and 50% to optimize the coefficient of friction and therefore braking;

- And / or glass fibers of between 1% and 39%, of length between 0.1 and 10 mm to optimize the tensile and impact strength;

- And / or anti-shrinkage blowing agents to promote the appearance;

- And / or agents for protection against the action of ultraviolet rays and bad weather in general to optimize the life of the rims subjected to atmospheric stresses.

The rim according to the invention is particularly intended for cycles such as road cycling, competition, all terrain, as well as wheelchairs and couplers in general (sulkys, for example).

The rim according to the invention of course has a generally circular shape with an axis (XX ') and extends in a plane (P) perpendicular to this axis. It should also be noted that the invention relates to the wheel fitted with the rim according to the invention or produced as the invention teaches.

Of course, the invention is not limited to the embodiments described and shown by way of examples, but it also includes all the technical equivalents and their combinations.

Claims

1. Wheel rim with spokes or spokes for cycles, couplings, wheelchairs, or the like, made of reinforced thermo-injectable plastic material, characterized in that it comprises two decoration flanges (20) and two structure structures ( 1) each consisting of a circular outer ring (2) secured by connecting bridges (7) of a circular inner ring (3).

2. Wheel rim according to claim 1, characterized in that the structural frames (1) are assembled by hot rolling of cylindrical (11) or conical (12) pins, through cylindrical (9) or conical holes ( 10).

3. Wheel rim according to claim 1, characterized in that the structural frames (1) are assembled by screwing, by riveting, by gluing or by welding.

4. Wheel rim according to any one of the preceding claims, characterized in that the composition of the materials used for the frame structures (1) comprises from 0.1% to 40% of a load of carbon fibers of length between 0.1 mm and 10 mm, or an inorganic isotopic filler, or a ceramic filler, or a glass fiber filler between 0.1 mm and 10 mm in length, or an anti-shrinkage blowing agent, or an agent for protection against ultraviolet rays, or a mixture thereof.

5. Wheel rim according to any one of the preceding claims, characterized in that the material making up the decoration flanges (20) is chosen from Acrylonitrile-Butadiene-Styrene (ABS) resins, or from Polystyrene-Acrylonitrile resins ( SAN).

6. Wheel rim according to any one of the preceding claims, characterized in that the decoration flanges (20) are formed of a circular crown whose distance (d) between the outside diameter and the internal diameter is between 10 mm and 100 mm, and whose thickness (e) is between 0.5 mm and 8 mm.

7. Wheel rim according to any one of the preceding claims, characterized in that the decoration flanges (20) comprise latching pins (21) tangent to the outside diameter of the flanges (20) of rectangular or circular section, which can be provided with one or more stiffening fin (s) (26), and having at their free end an increase in thickness (25) of triangular or partially circular section.

8. Wheel rim according to any one of the preceding claims, characterized in that the decoration flanges (20) have on their internal diameter increases in thickness (27) being in the form of beads of partially circular section or partially polylines, tangent and concentric to the inside diameter of the flanges (20).

9. Wheel rim according to any one of the preceding claims, characterized in that the inner ring (3) of the structural frames (1) comprises chamfer segments (13) or spoke segments (14) over the diameter the smallest of the crown (3).

10. Wheel rim according to any one of the preceding claims, characterized in that the connecting bridges (7) of the structural frames (1) have latching windows (8).

11. Wheel rim according to any one of the preceding claims, characterized in that the outer ring (2) and the inner ring (3) of the frame structures (1) are aligned or offset axially by a distance (h) between 0 and 80 mm.

12. Wheel rim according to any one of the preceding claims, characterized in that the connecting bridges (7) of the frame structures (1) form in pairs in the radial plane of the rim angles between 0 ° and 90 ° included, and each one on their length and in the axial plane of the rim an angle between 90 ° and 180 ° inclusive.

13. Wheel rim according to any one of the preceding claims, characterized in that, by a judicious choice of the location of the injection points of the plastic material in the frame structures (1) and in the flanges (20 ), the weld lines (17) of the fronts of molten material (16) at the end of injection into the molds are located on the outer (2) and inner (3) crowns midway between the connecting bridges ( 7) for the frames (1) and halfway between the snap pins (21) for the flanges (20).

14. Wheel rim according to any one of the preceding claims, characterized in that the decoration flanges (20) are snapped onto the structural frames (1) by means of the snap pins (21), increases thick (25) and (27), chamfer segments (13), spoke segments (14) and snap-in windows (8).

15. Wheel rim according to any one of the preceding claims, characterized in that the visible surfaces (f) of the decoration flanges (20) after snap-fastening are in the form of convex or concave envelopes.