GB693743A - Improvements in writing instruments - Google Patents

Abstract

693,743. Writing instruments. COMPANIA URUGUAYA DE FOMENTO INDUSTRIAL SOC. ANON. May 22, 1950. [June 14, 1949; Oct. 3, 1949] Nos. 15851/49 and 25415/49. Class 146 (iii). A writing instrument comprises a tubular casing having an opening at each end, a writing member mounted in the casing for projection to and retraction from a writing position in which a writing extremity of said member is exposed at one end of the casing, and projecting and retracting mechanism for effecting such movements of the writing member, the writing member being removable through the other or rear end of the casing leaving the mechanism in position. As applied to a ball-point pen, the pen 4 is slidably mounted in a casing 1, but is normally held in retracted position by a spring 13 interposed between a plunger 14 and a shoulder 12. The rear end of the plunger 14 is fixed within a sleeve 17 having a flange 18 carrying a skirt 19. The pen is retracted from the writing position, as shown in Fig. 1, by depression of an operating knob 23 screwed in the sleeve 17, the knob being pressed sufficiently to cause the sleeve 17 to force an expander ring 28 between flexible detents 21 carried by clip a 20, thus forcing the detents apart to allow a ring 16 on the plunger 14 to pass rearwardly through the detents when knob 23 is released and the plunger is retracted by the spring 13. After passage of the ring 16 the detents engage behind a second ring 15 to prevent further rearward movement of the plunger 14 and pen 4. The pen 4 may be removed from the casing by unscrewing the knob 23 and withdrawing the pen axially through the rear end of the casing, the knob having a reduced end 24 which is a push-fit in the open reservoir 9 of the pen for this purpose. The projecting mechanism is removed by detaching a pocket clip 27, by registering a hole 29 in the skirt 19 with one of a series of holes 30 in a nut 22 to permit the insertion of a tool to lock the nut and skirt together, and then by unscrewing the nut and skirt relatively to the casing 1. In a modification obviating the provision of holes 29, 30, the pocket clip has a solid head formed with a key fitting in a key way in the sleeve 17, the clip and skirt being secured by the knob 23 screwing into the sleeve 17. Specifications 673,747 and 609,817 are referred to. Reference has been directed by the Comptroller to Specification 641,595.