| 摘要 |
<P>PROBLEM TO BE SOLVED: To inexpensively provide a knock type ballpoint pen wherein a stop of ink in upward writing is prevented by pressurization and the ink apt to break off in initial writing is made possible to write with by the support of the pressurization. <P>SOLUTION: By moving a knock part forward and backward, an engaging body gearing with this part can be brought to engagement at advance and retreat positions inside a penholder tube. In front of the front end of the engaging body, a seal body which has a seal part being tubular and so shaped as to project in an inner hole part located almost in the front end and has an extensible-contractible deformation part formed at the back of the seal part and a contact part formed in the rear end is fixed to a tube body. An ink holding tube pierces the seal part of the seal body and is fitted in the inner hole part of the engaging body, while the seal part comes into close contact with the outer periphery of the ink holding tube and the inside of the penholder tube and that of the seal body are divided airtightly from each other in the front and the rear of the seal part. The rear end of the ink holding tube and the front end of the engaging body are so provided that air flows between them, and the engaging body is urged toward the rear of the penholder tube by a return spring. When knocking is made, a space section in the deformation part of the seal body is reduced and thereby the rear end of the ink is pressurized. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
