| 摘要 |
<p>The unit is assembled of an inner (20) and outer sleeves (21). The inner sleeve (20) is provided with two radial bores (22, 28), for the accommodation of small spheres (221, 281). A cylindrical central bore is located under a polygonal space (23) in order to hold a helical spring (251) and a positioning element (25) provided with a circular groove with a triangular cross section (252). The outer sleeve (21) has a circular groove at its inner surface at the same height as the lower radial bore (28) and an inclined upper edge complementary to the upper bore (22).</p> |
