GB816746A - Improvements in retractable ball-point pens - Google Patents

Abstract

816,746. Reservoir pens. SCRIPTO Inc. Sept. 2, 1957 [April 9, 1957], No. 27558/57. Class 146(3) A retractable ball-point pen comprises a rearwardly biased writing unit 16, floating latch means 57 slidably contained in the barrel 14 at the rear end of the writing unit, and a plunger 44 slidable in the rear end of the barrel and arranged to contact the rear end of the latch means 57, said latch means comprising two pawl members 72, 74 pivotally connected to each other and capable of relative rotation, the member 72 being rocked from a forward latched position to a retracted position or vice versa upon successive depressions of the plunger, and means for engaging the latch means 57 in projected and retracted positions. A mechanism housing 38 is secured in the rear portion of the barrel 14 and carries a U-shaped latch guide member 50, the base portion of which lies between the barrel 14 and the housing 38 and laterally extending guide rails 52 for the latch means 57 on either side thereof passing through slots in the housing. The member 50 is also formed with a latch lug 56 which extends through another slot in the mechanism housing. The latch pawl 72 consists of two flat portions united at their front ends by a base portion 78, the flat portions being formed with rearward extensions 97. The release pawl 74 lies between the flat portions of pawl 72 and is pivoted thereto at 80. A rearward extension 82 of the pawl 74 has surfaces 84, 86 for contact with a strike surface 64 and a cam surface 66 respectively on the front end of the plunger 44. The release pawl is also formed with shoulders 88, 90 a spring 94 being disposed between the shoulder 90 and a shoulder 92 on the plunger 44. With the writing unit in retracted position, Fig. 3, the shoulder 88 on the pawl 74 is held in engagement with the lug 56 by the force exerted by the writing unit biasing means acting on the base portion 78, which also tends to rock the pawl 72 in a clockwise direction. When the plunger is depressed strike surface 64 thereon contacts surface 84 on the extension 92 and pushes the latch means 57 and unit 16 into projected position wherein the extensions 97 of the latch pawl 72 engage under the lug 56 and latch the unit in that position. Upon release of pressure upon the plunger 44 the spring 94 moves it back out of contact with the pawl 74 and causes the extension 82 of the pawl to rock slightly away from the inner wall of the mechanism housing 38 until the lower edge 81 of the pawl contacts the base portion 78 of the latch pawl 72, Fig. 1. A second depression of the plunger causes the cam surface 66 thereon to engage the surface 86 of the extension 82 and rock the latch means clockwise (as shown in Fig. 1) so that the extensions 97 are disengaged from the lug 56 and the parts may resume the positions shown in Fig: 3 upon release of pressure on the plunger. Specifications 801,910 and 804,903 are referred to.