| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable a tip part of each writing body to be smoothly protruded/ retreated from a tip opening of a tip barrel, in spite of the mounting of a plurality of ball-point pen writing bodies in which ink housing parts have large cross- sectional areas for preventing deformation in a lateral direction with respect to a length-of-barrel direction. <P>SOLUTION: In the duplex writing instrument, the ball-point pen writing bodies are mounted in a barrel so that each writing tip part can be selectively and alternately protruded/retreated from the tip opening. In the ball-point pen writing body, its ink housing part, which has the large cross-sectional area for preventing the deformation in the lateral direction with respect to the length- of-barrel direction, is tightly mounted in a state of being almost prevented from oscillating, when each of the writing bodies is fitted and inserted into the barrel; a region for connecting the tip of the ball-point pen writing body with the ink housing part, which is bendably coupled for fixation by an elastic body, is flexibly provided so as to be easily displaced in the lateral direction with respect to the length-of-barrel direction; and the writing tip part of each of the writing bodies can be freely protruded/retreated from the tip opening of the tip barrel. <P>COPYRIGHT: (C)2003,JPO |
