| 摘要 |
<p>: A compound writing instrument, wherein a retractable mechanical pencil unit and a ball point pen unit are assembled in a lower barrel of the writing instrument, an upper barrel rotatable in one or two directions relative to said lower barrel around its axis overlaps said lower barrel and a cam mechanism engaging with said units for selectively shifting said units in the axial direction into a writing position is accomodated within said upper barrel of the writing instrument. By means of said cam mechanism, said upper barrel is shiftable relative to said lower barrel in the axial direction enough to feed out the lead of said mechanical pencil unit when this unit is in the writing position, while said upper barrel is non-shiftable relative to said lower barrel when said ball point pen unit is in the writing position.</p> |
