Patent GB-642437-A (GB)
Title: Improvements in or relating to fountain pens
IPC: B43K5/00
Filed: 1947-11-27
Abstract: 642,437. Fountain pens. DEHN, S. G. (Parker Pen Co.). Nov. 27, 1947, No. 31447. [Class 146 (iii)] A fountain pen comprises a barrel having a reservoir section, a feed section, a writing element, and a capillary filler and an ink storage element in said reservoir having walls defining an ink storage space capable of drawing ink thereinto and retaining ink therein by capillary attraction and is characterized in that the ink storage space includes a plurality of substantially parallel elongated capillary passages or cells extending longitudinally substantially throughout the filler and ink storage element, each of said passages or cells embodying means extending longitudinally which is of greater capillarity than the remainder of the passage or cell for ensuring continuity of the body of ink in the passage or cell, and is further characterized by ink feed means providing a capillary passage or passages of at least as great capillarity as said means extending longitudinally for connecting said cells in ink feeding relation to said writing element. A nib section 3 is screwed into one end of the barrel 1, Fig. 1 which houses a capillary cell structure 23 extending from adjacent the nib section 3 to an end space 19. The capillary structure comprises a plurality of longitudinal fins 24 spaced radially apart so as to provide capillary ink storage spaces 25 which are connected by a central passage 27 carrying a feed element 29 extending from the rear end of the fins 24 to the underside of the nib 6. The feed element 29 may comprise a series of nylon threads or other plastic material, ceramic material or vegetable or animal fibres may also be used. A pad 30 having a greater capillarity than the cells 25 and which also may be formed of nylon is provided adjacent the rear end of the nib section. An end member 33 provided with openings is provided at the rear end of the fins 24 so that the structure 23 is firmly held between this member 33 and the pad 30. A longitudinal air passage 35 is provided between the space 19 and the atmosphere by a channel-shaped member 36 disposed within the barrel 1 as shown in Fig. 4 and is extended by a groove 37 in the nib section 3. The passage 35 may be connected to adjacent cells by openings 38, the fins 24 may also be provided with openings 39 to connect the passage 35 with each cell 25; additional passages 35 may be provided. The pen is filled by unscrewing a rear cap 18 and placing the rear end of the pen in a supply of ink which is drawn by capillary attraction up the feed element 29 and into the cells 25 the innermost portions of which are filled first due to their higher capillarity than the outer portions. In writing, the capillarity established between the nib and a writing surface is sufficient to feed ink from the cells 25 to the nib slit 13. The relative capillarities of the feed element and cell structure is such that ink is drawn to the nib slit 13 and maintained there as long as the nib is in the writing position against a writing surface. Air is drawn into the pen to replace the ink used through the passage 35 and fills the cells 25 from the rear end of the pen. In a modification the pad 30 may be replaced by a portion of the feed element 29 which may be expanded laterally. A modified air passage may also be provided in place of the groove 37 consisting of a tube which connects the structure 23 with the atmosphere. In a further modification, Fig. 12, a nib 106 may be almost enclosed by a tapered portion of the barrel of the pen. The nib 106 has a split ring portion 107 and a slit 111 with a hole 110 which registers with an air vent 115 in the tapered barrel. The filler element 125 Figs. 11 and 14 comprises radial fins 126 extending longitudinally of the pen and provided with a central passage 132 carrying a feed element 130, spaces 129 are formed between the fins 126. The element 125 may comprise a series of sections each comprising sets of fins 126, 127 and 128 the fins in each set being of a different length, the forward section comprising only long fins 126, the intermediate section comprising shorter fins 127, and the fins 126, and the rear section comprising short fins 128, and fins 126 and 127, the latter section being spaced farthest from the nib 106 so that the capillarity of the spaces 129 increases as the distance from the nib increases. In a further modification, the filler element comprises a plurality of sections each containing radially disposed fins, which may be enclosed in a casing which forms a cartridge closed at its rear end by a perforated plate through which air may be expelled along an air passage formed in the interior of the casing. In a final modification the capillary spaces may be constituted by a plurality of longitudinal tubes disposed in the barrel which are filled by unscrewing a cap on the rear end of the pen and placing the rear end of the tubes below the surface of a supply of ink. Air is expelled by a central longitudinal air tube extending from an air space at the rear end of the pen to an air vent in the feed member adjacent the nib. To increase the capillarity and prevent "locking" of the ink in the tubes nylon threads are disposed centrally within the tubes. Alternatively, the capillary spaces may be constituted by corrugations formed in sheets of material which are each disposed between two plain sheets of plastic material which are circumferentially disposed around a central tube providing an air passage. Specification 634,735 is referred to.