Patent GB-851060-A (GB)
Title: Improvements in and relating to writing instruments of the ball point type
IPC: B43K24/08
Filed: 1957-04-25
Abstract: 851,060. Reservoir pens. BALLOGRAFVERKEN A.B. April 25, 1957 [April 30, 1956], No. 13138/57. Class 146(3). A retractable ball-point pen wherein the writing unit 6 is projected against the rearward bias of a spring 9 and retracted by the said spring upon successive depressions of a plunger 16, comprises a guiding sleeve 12 having an axial guide-bore 13 of a non-circular cross-section to accommodate a member 14 attached to the plunger and having also two axially spaced shoulders 22, 23, and a coupling pin 35 one end of which engages a centring slide 31, the slide being axially slidable in the guiding sleeve 12 and resting against the rear end of the writing unit, the opposite end of the coupling pin 35 being movable to two different positions by the member 14, the coupling pin also having a collar 37 which is pressed in one position against the shoulder 22 and in the other position against the shoulder 23. As shown in Fig. 5 the member 14 is of rectangular crosssection for sliding within the guide-bore 13 and has two oppositely inclined faces 20, 21 at the end adjacent to the coupling pin. The shoulders 22, 23 are formed in the guiding sleeve at the front end of the guide-bore 13 at the narrow longitudinal faces 25, 26 thereof. Adjacent to the shoulder 22 the guiding sleeve is also formed with slide surfaces 29, 30, the slide surface 29 inclining upwards towards the longitudinal surface 27 of the guide-bore 13 and also inclining towards the narrow surface 25 thereof and the slide surface 30 inclining similarly towards the surfaces 28 and 26 of the guide-bore. The collar 37 on the coupling pin 35 is formed with an annular flange on its rear surface which engages behind a stop member 24 on the shoulder 23 to maintain the writing unit 6 in projected position, Fig. 1. To retract the unit the plunger 15 is depressed whereby the face 20 on the member 14 engages the rear end 36 of the coupling pin, and advances it until it reaches the slide surface 29 when it cams the end 36 out on to the slide surface 29. Owing to the inclination of the slide surface the end 36 follows the path indicated by the arrow in Fig. 3 and eventually re-enters the guide-bore 13 adjcaent to the narrow surface 25 thereof, the collar 37 abutting against the shoulder 22. The unit is projected by a further depression of the plunger whereby the face 21 on the member 14 advances the coupling pin 35 until its rear end 36 reaches the slide surface 30, owing to the inclination of which the coupling pin 35 adopts the position shewn in Fig. 1 with the collar 37 abutting the shoulder 23. The centring slide 31 has a narrow transverse slot 32 on its forward face which extends on both sides of the rear end of the writing unit to supply air thereto. The mechanism is assembled as a unit in a sheet-metal sleeve 1 which is connected by a protuberance 2 to. a threaded bushing 3 which is screwed into the barrel 4. A cover 10 carrying a pocket clip is removably secured to the sleeve 1 by outwardly bowed portions of the sleeve which engage the inner surface of the cover.