Method of producing a wheel of synthetics material.

The invention relates to a plastic wheel and a method for its manufacture. position consisting of rims, spokes and hub holder.

There is a known consisting of glass fiber reinforced plastic spoked small diameter and an odd number of spokes, which is molded into the hub.

The disadvantage of this spoke wheel is that. As a result of the confluence of the mass flows in the rim there is a weakening of the material strength that will result in particular with respect to shock the destruction of the rim.

The invention has for its object to find a Kunststoffspeichenrad, which allows to use the material properties fully under mechanical stress, in particular shock (curb), which possesses smooth running characteristics and which can be produced in one operation.

The object is achieved in that the rim which has, except for the adjoining reinforcements range, preferably circumferentially directed amplifier elements, is held by an even number spokes.

This plastic wheel, which in contrast to the previously present expert opinion with an even number of spokes excl is erüstet, a high concentricity is achieved because the preferably aligned in the wheel peripheral amplifier elements, which may consist of mineral fiber, over the entire circumference uniform structure of the material is achieved, the highest of the strength demands. Of course, also this effect with polymers are obtained, which form a liquid crystalline melt. The values ​​thus obtained in strength characteristics may rise (curb) at five to six times with respect to shock. The critical confluences of mass flows can be arranged in the region of the reinforcements as spoke or overflow. The injection production of thermoplastics allowed without large additional costs in terms of strength, a favorable design of the load-bearing. the parts, so that it is possible in particular plastic large diameter wheels (26 ", 28" and larger) produce.

In a particular embodiment, the rim with one along the circumference. fanges arranged pulling element provided.

The tensile member of a roving, wire, non-woven and / or woven fabric made of metal, plastic (aromat. PA, polyimide), textile and carbon, and mineral substances, eg. As glass, may be composed, are the plastic wheel an additional hoop strength, which is advantageous at higher stress levels, or in lightweight.

In a further embodiment, the spokes are of resilient construction.

By curved in the plane of spokes and by changing the cross-sections of the spring behavior can be specified in a wide range, an increased ride comfort was achieved by the true-running wheel.

In a method for producing the plastic wheel, the mass flows are injected into individual spokes and guided so that they flow together in the intermediate, arranged in an odd number on the rim spokes.

If the quotient of spokes by number of injection points is an even number, the Zusammenflußnähte lie in specifying appropriate flow resistances in the spokes depending on the requirements in the top, middle or footer, so that the amplifier elements in the freely tensioned rim inevitably preferably tangentially in circumferential direction are aligned, whereby there is achieved the desired strength. The deflection of the amplifier elements in the region of the spokes makes in terms of strength because of the gain in the direction of the hub (spoke) unnoticeable.

On plastics to glass fiber-reinforced, thermoplastically processable polyamide molding compounds have proven particularly useful, which are composed of:<ul><li>A PA 6, PA 6.6, their copolymers or mixtures of polyamides having intrinsic viscosities of 2.5 to 3.5 dl / g, preferably 2.7 to 3.0 dl / g, measured in m-cresol,</li><li>B a Elastificator,</li><li>C a fibrous reinforcing agent.</li></ul>

Next show good results fiberglass reinforced, processed thermoplastically. beitbare polyester molding compositions which are composed of:<ul><li>A a thermoplastic resin phase,</li><li>B a Elastificator,</li><li>C a fibrous reinforcing agent</li></ul>

The resin phase A is 75 to 100%, preferably to 80-95% of polyalkylene terephthalate and 25-0, etc., preferably 20 to 5% of aromatic polycarbonate.

Among polyalkylene is understood PBTP or PETP, copolyesters based PBTP or PETP and mixtures of said polyesters in any mixing ratio with intrinsic viscosities from 0.60 to 1.20 dl / g as measured in a solvent mixture of 50 parts of phenol and 50 parts of 1, 2-dichlorobenzene aromatic polycarbonate is preferably understood to be a bisphenol-a polycarbonate with intrinsic viscosities from 0.45 to 0.55 dl / g, measured in methylene chloride.

The aforementioned products are impact modified by means of suitable elastomers in an amount of 1 to 25%, preferably 5 to 20%, based on the mixture of A and B. The term "suitable elastomers" impact-resistant modifiers are understood to be of as discrete particles having a particle size 0.1 to 0.6 microns, preferably 0.2 to 0.5 microns, dispersed in the resin phase A.

The products contain fibrous reinforcing agents, preferably mineral fiber-shaped products, such. As glass fibers, with a L / D ratio of 10/1 to 50/1 in an amount of 10 to 50%, preferably 20 to 40% based on the total mixture of A + B + C.

Examples of the invention are illustrated in the drawings and are described in more detail below.

Show it:<ul><li>FIG. 1 view of a 8-spoke plastic wheel,</li><li>Fig. 2 cross-section through the rim,</li><li>FIG. 3 view of a wheel with resilient spokes.</li></ul>

In Fig. 1 a plastic wheel 1 is shown with eight I-shaped spokes 2, which are joined in the middle with a hub mount 3 and out to the rim. 4 The injection points 5 are in the ratio: number memory 2 divided by number of injection points 5 arranged. This results in an even number. The confluence 6 of the mass flows in the range within the spoke 2, possibly in the not shown overflow.

In FIG. 2 is a cross section of the rim 4 is shown, wherein the rim flange 7 grows up to the center corresponding to the increase of the strength stress in the material thickness. In the plane of symmetry includes integrally molded ring 8 with a reinforced foot 9 on, the latter being the inertia. moment substantially increased

In Fig. 3, the spoke 2, which connects the hub grip 3 and the rim 4, bent so that it yields resiliently in the case of load.