| 摘要 |
PROBLEM TO BE SOLVED: To provide a dual type writing instrument for widely ensuring a space for containing writing elements in a thickness of a barrel satisfying portability and handling operability by mounting two types of writing elements each having at least one writing element of a large-sized intermediate viscosity water base ink and low viscosity oil base ink ballpoint pen in a barrel. SOLUTION: The dual type writing instrument comprises a rotary shaft 33 rotatably disposed in a range of substantially 180 degrees with respect to a barrel in a rear inner hole of the barrel and formed with cam grooves 35 on a periphery of the shaft, an actuator 42 fixed integrally with or separately from a rear end of the shaft 33 protruding from a rear end of the barrel in such a manner that the actuator 42 is held rotatably with respect to the barrel, a pair of sliding dowels 46a, 46b having protruding parts 47a, 47b engaged with the grooves 35 of the shaft 33 and formed at opposed insides to be guided longitudinally movably to an inner hole of the barrel, and writing elements 1a, 1b respectively provided forward of the dwells to interlock with the dwells. In this case, the dwells are alternately longitudinally moved by rotation of the shaft upon rotation of the actuator so that writing tips of the writing elements are flexible in a centripetal direction to be projectable from an end port of the barrel. |
