| 摘要 |
<p>A hockey stick (1) comprised on a head (2), a stem (3), a handle (4) and a bead (5) showing a division between the parts 3 and 4. The stem (3) includes a slot (6) substantially between the bead (5) and the head (2). The hockey stick is formed by injection moulding a foamed thermoplastics material, usually glass fibre reinforced nylon, such that the density through the head and stem is greater in an outer skin region than in a region contained by the outer skin. The foamed thermoplastic material is formed by the inclusion of a foaming or blowing agent within the plastic material before injection into the mould and the foamed plastics material is held under substantive pressure which is inherently lessened upon release into the mould. The glass fibre reinforcement has an average length of 8 mm and comprises 80 % of the weight of the fibre reinforced plastics material. The quantity of foaming agent is sufficient to reduce the weight of the foamed plastics material to 80 % of that which would be the case if not so foamed.</p> |
