Patent GB-814765-A (GB)
Title: Improvements in fountain pens
IPC: B43K5/18
Filed: 1956-10-24
Abstract: 814,765. Reservoir pens. PARKER PEN CO. Oct. 24, 1956 [Oct. 24, 1955; Oct. 28, 1955], No. 32453/56. Class 146(3) A reservoir pen comprises an ink reservoir, a writing point, feed means connecting the reservoir and the writing point, the reservoir including a capillary element capable of filling with ink by capillary action, a filling entrance leading to the capillary element, and means for closing the filling entrance to create subatmospheric pressure in the reservoir during write-out of ink therefrom, the feed means including one or more passages thrdough which ink is fed from the reservoir to the writing point and through which air from the atmosphere enters the reservoir to replace ink written out from the latter to vary the sub-atmospheric pressure within. The barrel 14 comprises a front section 26 and rear section 28 secured together by a screwed sleeve 30; the rear section is readily removable for filling purpose, while the front section is cemented to the sleeve 30. A decorative band 36 of L-shaped cross-section forms an abutment between the sections 26 and 28. The rear end of the barrel has a screw 50 having a head 52 carrying decorative gauze 58. The barrel houses a reservoir 16 which draws in and retains ink by capillary attraction in the manner described in Specification 646,726. The reservoir 16 has a cylindrical casing 18 and is secured at its front end to an ink collector. A filling valve 19 in the rear end of the casing 18 includes a dome portion 82 having filling apertures 84. Material of high capillarity, e.g. felt or sponge, is interposed between the portion 82 and a plug 88 having radial rib 89 defining apertures 90. The ribs receive and locate the rear end of a feedbar 20. The dome portion 82 prevents the intake of sediment from the bottom of an ink bottle during filling. The feed-bar 20, Figs. 13, and 14, which may be synthetic plastic is generally cylindrical apart from cut-away portions forming flats 94, 96. Primary ink feed passages 98 of uniform cross-section extend the length of the feed-bar. Each passage 98 includes a wide portion 102, Fig. 18, and an inner narrower portion 104. A central passage 100 consisting of portions 106, 108, and 110, Fig. 14, controls the flow of ink to the nib, since should ink block the portion 108 air cannot pass into the reservoir. The portion 110 communicates with the passages 98 at its front end. An ink feed groove 112, Fig. 18, at the bottom of the passage 100 allows ink to flow towards the nib, while air passes in the opposite direction towards the reservoir. The passages 98 and 100 connect the ink storage spaces in reservoir 16 with the nib 22, Fig. 3. The nib 22 comprises a writing point 114 and a shank 116 having a rear tubular portion 118 split on its underside to form wings 122, Fig. 5, engaging the flat surface 94 of the feed-bar; thereby locking the nib and feed-bar together. The writing point has a slit 124, Fig. 3, and an aperture 126 at the rear end thereof. The wings 122, Fig. 5, rest on shoulders 129 in bore 44 of the front barrel section 26. An ink collector 24, Fig. 9, surrounding the feed-bar 20, Fig. 3, has overflow spaces 166 for receiving ink in excess of that required for writing purposes in the manner described in Specification 534,657. The collector has a tubular body 130, Fig. 9, with stepped bore portions 132, 136, and 138. The feed-bar 20, Fig. 3, is mounted in the bore 132. The front end of the collector has a reduced portion 140 engaging a bore 44 in the front barrel section 26, the collector being locked against rotation relative to the section by a lug 150, Fig. 3, engaging a notch 148 in the bore 138. The rear end of the collector has a portion 152 fitting into the casing 18, the joint being sealed by a ring 156. An annular space 160, formed between the feedbar and bore 132, adjoins an arcuate space 162. The tubular portion 118 of the nib 22 fits into the bore portion 138. The spaces 166 are connected by a capillary passage 168 and an air channel 170. Slots 176 formed in a tapered bore portion 134 of the collector communicate with a rearwardly diverging space 178 formed between the feed-bar and bore portion 134 in order to feed ink radially inwards from the front end of the reservoir to the passages 98, 100. Air enters the air passage 170 via an annular recess 180, an aperture 182, passages 184, 186 beneath the flat 94 of the feed-bar, a passage 188 below the wings 122, a passage 190 between the shoulder 129, and a passage 192 between the flat 96 and the bore 44. An aperture 196 connects the passage 100 with the air channel 170. In operation, the pen is filled by removing the section 28 and immersing the filling valve 19 in an ink supply. The hydrostatic, head of ink forces ink through the valve 19 such that it is then drawn into the reservoir 16 by capillary attraction. After a predetermined time, the pen is removed from the ink supply, and held point downwards such that the ink flows towards the nib. The valve 19 is then closed by a resilient seat 74 in a cup-shaped member within the section 28, the member being pushed forwardly by a spring 72. Air entering the reservoir to replace ink withdrawn has to flow through the portion 108 of the passage 100. Before writing, the feed passages 98 and 100 are filled or partly filled with ink, while vacuum in the reservoir holds the ink column in a state of equilibrium. As writing begins, ink is drawn from the nib on to the paper, the supply of ink at the nib being replenished through the passages 98; the degree of vacuum in the reservoir increases until air bubbles through the portion 108 of the passage 100 into the reservoir, thus facilitating further withdrawal of ink. The transfer of ink from the feed passages to the nib may be facilitated by placing capillary pads 218, 220, Fig. 25, on either side of the nib. The pads which may be separate pieces or formed as a sleeve are of cotton flock, synthetic filaments, sponge rubber, or cotton fibres. In a modification, the reservoir may be formed from a sheet 320, Fig. 27, of thin plastic or metal foil having elongated spacers 321 spaced apart and inclined as shown; the spaces may be integral with or attached to the sheet. The sheet 321 is rolled to form a cylindrical reservoir 322, Fig. 31, having capillary ink storage spaces 324 interconnected by perforations 325, Fig. 27. The spacers increase in length and may also increase in height towards the outer turn of the sheet.