| 摘要 |
A writing point assembly for a tubular drafting pen includes an elongated tubular shell from one end of which a tubular, capillary nib projects. A sliding weight guided in the shell axially bounds an ink storage space in the other end of the shell which is radially imperforate. Ink may flow from the storage space to the nib through an ink feeding channel between the weight and an inner shell wall. Threads on a first section of the outer, axial shell face permit the shell to be fastened in a tubular holder. A collar on the outer axial shell face is spaced intermediate the first face section and the nib center the shell in the holder. The collar defines a portion of an air channel axially by-passing the collar and communicating with the ambient atmosphere. A second axial portion of the outer face intermediate the threads and the other end of the shell defines a further portion of an air channel which communicates with the ink storage space.
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