| 摘要 |
<p>The core comprises two symmetrically superimposable halves, each comprising a rear body member (12) having a first internal flat surface (18), a polyhedral projection (20) extending from the surface (18), a curved surface having a cylindrical portion (32) and a doughnut-shaped portion (30), and a first upper surface (38); two centre body members (14) having a second lateral surface (48), a second internal surface (52), a curved surface with a cylindrical portion (58) and a doughnut-shaped portion (56), a flat front surface (54) and a second upper surface (60); and an inner body member (16) having a third internal surface (62), a curved surface with a cylindrical portion (68) and a doughnut-shaped portion (66), and a third upper surface (70). The core may undergo successively a translation movement affecting only the rear body member (12); a second movement perpendicular to the former and a third movement parallel to the first movement. <IMAGE></p> |
