Thermoplastic bow limb
View Patent ↗An archery bow limb may comprise a thermoplastic material having reinforcing. A tension side of the bow limb may have continuous unidirectional reinforcing spanning substantially the entire length of the bow limb. A method of manufacturing such bow limbs may comprise building up layers of reinforcing fibers preimpregnated with thermoplastic resin (prepregs) over a core of thermoplastic material to make a preform, and compression molding the preform to consolidate the thermoplastic of the prepreg layers to one another and to the core.
1. An archery bow limb comprising:
a tension side layer, a core layer and a compression side layer;
each layer comprising a thermoplastic material;
wherein the tension side layer further comprises a plurality of reinforcing fibers, the reinforcing fibers oriented substantially parallel to a lengthwise axis of the bow limb and continuously spanning a substantial length of the bow limb;
the bow limb further comprising an intermediate layer having first reinforcing fibers that are substantially parallel to one another and nonparallel to the reinforcing fibers of the tension side layer.
2. The bow limb of claim 1 , wherein the compression side layer further comprises a plurality of reinforcing fibers, the reinforcing fibers oriented substantially parallel to a lengthwise axis of the bow limb and continuously spanning a substantial length of the bow limb.
3. The bow limb of claim 1 , wherein the core layer further comprises a plurality of short reinforcing fibers suspended throughout the core layer.
4. The bow limb of claim 1 , wherein the intermediate layer further comprises second reinforcing fibers that are substantially parallel to one another and nonparallel to the first reinforcing fibers.
5. The bow limb of claim 4 , wherein the first reinforcing fibers of the intermediate layer are oriented at a predetermined positive angle to the reinforcing fibers of the tension side layer, the second reinforcing fibers of the intermediate layer are oriented at a predetermined negative angle to the reinforcing fibers of the tension side layer, an absolute value of the positive angle being equal to an absolute value of the negative angle.
6. The bow limb of claim 1 , wherein the intermediate layer is located between the core layer and the tension side layer.
7. The bow limb of claim 1 , wherein the intermediate layer is located between the core layer and the compression side layer.
8. The bow limb of claim 1 , wherein the tension side layer is at least 0.03 inches thick.
9. The bow limb of claim 8 , wherein the compression side layer is at least 0.03 inches thick.
10. The bow limb of claim 1 , wherein the bow limb does not comprise a thermoset material.