GB598726A - Improvements in and relating to self-filling fountain pens - Google Patents

Abstract

598,726. Fountain pens. WADE, E. E. S. Sept. 7, 1945, Nos. 23082 and 29938. [Class 146 (iii)] [Also in Group XXVI] The piston of a vacuum self-filling fountain pen is in two parts telescoping into each other and is carried in a plug secured to the rear end of the barrel forming the ink chamber, the two parts being connected by formations on one part engaging helical means in the other for effecting the telescoping movement by rotation of a fingerpiece on the actuating part and the rear end of the ink reservoir has a seat for the rear face of the piston which acts as a seal when the parts are telescoped. In. one form Fig. 3, a hollow piston rod 30 of generally square cross-section, has rounded corners threaded to engage a tapped sleeve 31, and slides in a similarly shaped aperture in an annular projection 19 at the end of the ferrule 2 which is secured into the barrel 1 of the pen. The piston composed of cork or of two leather or fibre discs 33 and a graphited or a paraffin impregnated felt disc 34 screwed into the piston rod 310 by a bolt 32, is normally pressed against the projection 19 to prevent leakage of ink, and the sleeve 31 is screwed down by the finger piece 11, which is plugged after assembly at 37, in which position the flange 15 fits against the ferrule 2. To fill the pen, the sleeve 31 is unscrewed till the tapped portion reaches the limit stop 35, when the piston is operated. A spring may be introduced, either in front of or behind the piston to effect automatic return of the piston during filling, friction washers being mounted at the ends of the spring if desired. In a modification, the finger piece of the actuating member carries a central rod screwing into a hollow piston rod. The projection 19, in which the piston rod slides, may be made separately and cemented to the barrel or ferrule or may be made integral with the barrel. The engaging faces of the projection 19 and piston may be conical in formation. The screw threads of the telescoping members may be replaced by a pin guided by a simple or multiple differential spiral groove having a coarse pitch at the centre for rapid telescoping movement but fine pitch at both ends. Stylo or ordinary nibs may be employed and the piston rod may be cylindrical and rotation prevented by a longitudinal groove engaging a projection or captive ball on the annular projection 19.