| 摘要 |
<p>The particle ski is fitted with a cross-country ski binding and has a single wheel at the front and a pair of wheels at the back. The body of the ski is a square-section Al alloy tube, and the special wheel bearings combine a free-wheel and needle bearings (the needle bearings on either side of the free-wheel). Many details and variants are specified, of which the following are a few: a circular tube may be put in the square tube, to strengthen it; the tube may be in two parts, with a resilient connection between; the wheels may be of polyurethane and butadiene witha dia. of 100mm or of polyurethane and rubber of 80mm dia.</p> |
