GB815963A - Improvements in or relating to writing units for fountain pens - Google Patents

Abstract

815,963. Reservoir pens. RAY, F. Nov. 26, 1957 [Nov. 26, 1956], No. 36836/57. Class 146(3) A writing unit for a ball point pen of the kind having an ink reservoir tube of non-capillary internal cross-section, the tube being open at the end opposite the ball point, comprises an ink meniscus supporting device e extending lengthwise with respect to the tube and including a rod located within the tube and a wire coil encircling, the rod, the coil comprising a series of successive convolutions spaced laterally from the rod and from the inner wall of the tube. The rod 17 is slidably accommodated a t each end in blind bores 22, 32 formed in anchor pieces 19, 20 respectively. The wire coil is formed by a helical spring 18 threaded on reduced portions of the anchor pieces 19, 20 while under tension, thus holding together the parts 17, 19, 20. The anchor piece 20 has three ink channels 33 and the anchor piece 19 has an air passage 29. The reservoir tube 10 has three indentations 40 which engage the outer periphery of the spring 18 and help locate it substantially midway between the remainder of the inner wall of the reservoir and the rod 17. The supporting device is inserted from the rear end of the tube, the channels 33 in the anchor piece 20 being positioned so as to pass over the indentations 40, and, the anchor piece 19 being a friction fit in the rear end of the tube. The air-ink surface meniscus is so supported by the wall of the tube, the wire coil and the rod that it maintains the position shown whatever the position of the pen. The anchor pieces 19, 20 may be made of a plastic material and the rod 17 and spring 18 of hard drawn brass wire. The tube 10 and spring 18 may taper towards their forward ends.