| 摘要 |
<p>A utility knife comprises a lower elongate part shell (1) and an upper such part shell (3) forwardly fitted with interengaging wedging surfaces whereby they clamp together on relative longitudinal movement. This movement is achieved by turning nut (2) on shank (8) to bear on wall (30). The loosening of the nut (2) to unclamp the part shells and thus permit blade (43) to be pushed forward with slider (42) by pushbutton (41) does not separate the part shells (1) and (3) since the end spur (9) of the shank (8) still rides on arresting web (37). Maximum unscrewing of the nut, however, permits separation e.g. for access to stack of spare blades (60) resiliently held at (59) in the rearward part of shell (1) (now unencumbered by the conventional screw-shank), but does not lead to loss of nut (2) because of a complementary detent configuration (25) at the end of the shank and in the end wall (2a) of the nut prevents complete nut/shank separation. Spur (9) can be upwardly sloping at its underside and thus constitute an auxiliary clamping means for part shell (1) against part shell (3).</p> |
