GB825211A - Improvements in or relating to point retracting mechanisms for writing instruments - Google Patents

Abstract

825,211. Writing instruments. MABIE, TODD & CO. Ltd. Nov. 29, 1956 [Feb. 9, 1956], No. 4042/56. Class 146(3) A retractable writing instrument has a rearwardly biased writing unit 2, a sleeve 4 to receive said writing unit, a cylindrical cam member 6 rotationally mounted on said sleeve and disposed coaxially of the unit and secured against appreciable axial movement relative thereto, and cam followers formed or mounted on the casing for co-operation with cam faces 9, 10 at the opposed ends of the member 6, the cam faces being such as to rotate the cam member on the sleeve on successive actuations of the mechanism to positions wherein the writing unit adopts alternately the retracted and projected positions. The rear end of the writing unit 2 is push-fitted into the sleeve 4, and the rear end of the sleeve projects from the barrel to carry an actuating knob 5. The upper and lower cam faces 9, 10 are arranged as shown in Fig. 3. When the unit 2 is retracted splines 11 formed on the barrel part 26 engage the bottoms of the deep depressions 15 of the upper cam face 9 of the member 6 which is held in this position by a spring 13 urging the sleeve 4 rearwards. On depression of the knob 5 the member 6 is carried forward until projections 12a on a bush 12 which unites the barrel portions 25, 26 engage the inclined -faces of the depressions 16 of the cam face 10, cause the member to rotate and come to rest in the bottoms of the depressions. When pressure on the knob is released, the spring 13 carries the member 6 back until the splines 11 engage the inclined surfaces of the depressions 14, cause the member to rotate, and come to rest in the bottoms of the depressions. The unit 2 is now in projected position. A second actuation of the knob 5 causes the unit 2 to reassume the retracted position. The bush 12 threadedly engages the barrel part 25 and carries splines 27 and beads 28 to co-operate with corresponding slots 29 and recesses 30 in the barrel part 26.