GB1012158A - Fluid-dispensing cartridges - Google Patents

Abstract

1,012,158. Reservoir pens. F. A. ECKERLE. Nov. 22, 1962 [Nov. 22, 1961], No. 44261/62. Heading B6P. [Also in Division F1] The liquid of a dispensing cartridge, e.g. the ink column of a ball-pen, is subjected at its inner end to the pressure of a gas which is generated in proportion to the rate at which the liquid is used so as to maintain a constant pressure. In one form, Fig. 1, the barrel 12, which has a larger than capillary size diameter, is made of one metal, e.g. brass, and has a strip or strips 24 thereon of another metal, e.g. zinc, the two metals having different positions in the electromotive series. The usual grease plug 20 floats on the ink surface and between it and a rubber cap 16 closing the barrel is an electrolyte 22. One of the metal surfaces 12, 16 or both is or are coated with an insulating layer 26 which is dissolved away by the plug 20 as it follows the ink so as to expose the two metals and cause the generation of gas as the ink is used, the pressure above the ink column thus being maintained. The electrolyte may be in paste form so that it moves with the follower 20. Alternatively the material of the follower may be such that it acts as an electrolyte as well as a solvent. Moreover, the electrolyte may be constituted to act also as the solvent. If, however, the ink is such that it is incapable of acting as an electrolyte, no protective coating on the metals is necessary. The barrel may be of non-metallic material and a composite strip of the two metals may be supported from the cap, and may comprise two wires twisted together. In another form, the gas may be produced by chemical action. A rod coated with sodium carbide or sodium peroxide is supported axially in the barrel, and a quantity of water or aqueous paste is placed above the follower 20. As parts of the rod are exposed by movement of the follower, the coating thereon coacts with the water to produce the gas.