GB853800A - Improvements in writing instruments - Google Patents

Abstract

853,800. Reservoir pens. ROLL-TIP (ENGLAND) Ltd. Jan. 14, 1959 [Jan. 16, 1958], No. 1559/58. Class 146(3). A rectractable ball-point pen comprises a barrel 16, a cap 18 of synthetic plastic material mounted to rotate on the rear portion of the barrel and in screw-threaded engagement therewith, and a writing unit 10 movable axially in the barrel by rotating the cap 18, the cap 18 being inseparably connected to the rear end of the writing unit by a connector 12 of harder synthetic plastic material than the cap and having integral projecting barbs 15 which are engaged with the interior of the cap. The connector 12 which may be of polystyrene or high tensile cellulose acetate has a portion fitted into the rear end of the writing unit, an enlarged portion 13 on which the barbs 15 are formed, and a head 14. The cap 18 which may be of cellulose acetate has an internal shoulder 23 which is slidable between two shoulders 21, 22 on the barrel to limit longitudinal relative movement of the cap and the barrel, and the rear end of the barrel is slotted at 24 to allow the shoulder 23 to be forced over the shoulder 22 during assembly. The assembled writing unit and connector are inserted in the barrel from the rear, passing through the open rear end of the cap 18 until the head 14 abuts against the rear end of the cap. In this position the barbs 15 bite into the softer plastic material of the cap so that the connector and cap are for all practical purposes inseparable. Reference has been directed by the Comptroller to Specification 788,257.