GB900300A - Improvements in fountain pens - Google Patents

Abstract

900,300. Reservoir pens. ESTERBROOK PEN CO. May 25, 1959 [May 28, 1958], No. 17690/59. Class 146 (3). A cartridge-filled reservoir pen comprises a writing assembly consisting of a nib and feedbar assembled as a unit in a sleeve detachably mounted in the nib section, and an ink-feeding assembly interposed between the writing assembly and the ink-cartridge and consisting of a body member having a bore in axial alignment with the cartridge and a tubular cutting element mounted in the bore of the body member, which element pierces a diaphragm sealing one end of the cartridge whenthe parts are assembled and allows ink and air to pass along its bore. The nib section 12 houses the writing assembly which is enclosed in a sleeve 15, and a member 20 which is longitudinally slidable therein. The member 20 has an axial bore into the rear end of which is fitted a piercing tube 23. A rod 24, one side of which is cut away to leave a capillary air passage 24c and which has a capillary ink groove 24a, is frictionally fitted in the tube 23 and extends forwards therefrom into the bore of the member 20. The front end of the member 20 is formed with an annular ridge 25 which abuts against the rear end of the feed-bar carried in the sleeve 15, and with diametral capillary slots 26, 27 at right angles to each other. A disc 22, e.g. of metal, is mounted on the rear end of the member 20 for abutment with the front end of the ink cartridge 16. A resilient washer 21 surrounds the member 20 and prevents any leakage of ink from the cartridge from reaching the writing assembly. A sealed polyethylene cartridge inserted in the pen barrel is ruptured at 16b by the piercing tube 23 when the writing assembly is screwed home in the nib section, which operation causes rearward movement of the member 20. Ink flows down the groove 24a and air passage 24c and fills the annular space 20b between the rod 24 and the member 20. Ink is fed to the ink grooves in the feed bar down the slot 26 which is deeper and narrower than the slot 27 and is drawn first from the air passage 24c as this has smaller capillarity than the groove 24a and space 20b. Air enters the cartridge through the slot 27 and in the form of bubbles along the passage 24c. The barrel contains a reserve cartridge 16 to the rear of the one in use.