GB970407A - Writing instrument - Google Patents

Abstract

970,407. Cartridge reservoir marking pens. DAVID KAHN Inc. Nov. 21, 1961 [July 26, 1961], No. 41605/61. Heading B6P. Nib section. -A nib section 15 of a cartridge reservoir marking pen comprises a holder 17 having a bore 20, a writing tip 24 of an absorbent material such as felt slidably mounted in the bore, a valve member 26 having an upwardly flaring thin annular wall valve plug 28 of a resilient synthetic plastic material such as nylon, and a spring 34 biasing the valve plug 28 toward a valve seat 23 in the bore of the holder. A rearward pressure on the writing tip 24 forces the valve plug 28 away from the valve seat 23 and allows ink to flow to the tip 24. A bush 35 is tightly fitted into the upper end of the holder 17 and serves to guide the valve member centrally within the bore 20. Cartridge reservoir.-The pen barrel 16 is of the replaceable cartridge type. The ink is normally sealed within the barrel or reservoir 16 by a sealing bush 47 force-fitted into the forward end. When fitting a new reservoir, the nib section 15 is screwed into the reservoir 16 (Fig. 2) and a piercing extension 37 of the bush 35 cuts through the periphery of an operable partition 52. Cap and sealing arrangements.-A cap 11 is provided with an inner cap 54 comprising an annular shoulder 56 and a blind bore 55. When the pen is inserted within the cap, the forward extremity 57 of the holder 17 engages the annular shoulder 56 so that the writing tip 24 is sealed within the bore 55, thereby preventing evaporation of the ink. Bushes 47 and 35, valve member 26 and the inner cap 54 are all of synthetic plastic material such as nylon, which because of its yielding nature, provide fluid light seals at the abutting edges and prevents undesirable leakage of ink. The reservoir 16 and the holder 17 are of synthetic plastic material such as cellulose acetobutyrate. 'In other embodiments (not illustrated) the cross-section of certain components of the pen, such as the writing tip 24 and the valve member 26 need not necessarily be circular. U.S.A. Specifications 1,867,467 and 2,250,444 are referred to.