GB912359A - Improvements relating to fountain pens - Google Patents

Abstract

912,359. Reservoir pens. DAVENPORT, R. J. Feb. 20, 1959 [Feb. 20, 1958], No. 5620/58. Class 146 (3). In a reservoir pen with manually-operable means for increasing the air pressure in the ink reservoir to cause the ink to flow towards the writing point, a bellows has its interior in communication with the reservoir by means of a one-way valve, whereby expansion of the bellows sucks air into the bellows and compression of the bellows causes air to be forced through the one-way valve into the reservoir. As shown, a ball-point pen of the point-retracting kind comprises a two-part barrel 15, 16 having an ink reservoir and writing unit 33 secured in a member 28 which has a neck portion 27 slidably mounted in the barrel, the unit being urged inwardly of the barrel by a spring 34. The writing unit may be urged into writing position by a plunger 22 on a known projection mechanism 20 carried by a cap 18 which is slidably mounted on the barrel 15. The plunger 22 is within a bellows extension 23 of the mechanism 20, and a washer 24 on the bellows abuts a face 25 within the barrel and encloses the free end of the neck 27. A hole 30 in the neck 27 terminates within the reservoir in a one-way valve 32. The barrel has opposed air holes 26 adjacent the washer 24. When unit 33 is retracted, the bellows 23 expands, and air is sucked in through the holes 26 and the end of the washer 24. When the cap 18 and mechanism 20 is depressed, the air trapped within the bellows is compressed and forced into the unit 33 through the hole 30 and one-way valve 32. On continued movement of the cap &c., the plunger 22 engages the neck 27 and projects the writing unit into writing position, where it is locked by known means. In a modification (Fig. 1, not shown), a bellows which is secured to, or integral with, a ball-point writing unit arranged in a barrel, is compressed by depressing a knob at the end of the barrel. The writing unit may be extended to form a bellows, and two one-way air valves are arranged therein, the valves comprising short lengths of rubber tubing with flattened ends.