Patent GB-673845-A (GB)
Title: Improvements in propelling pencils
IPC: B43K21/20
Filed: 1949-05-02
Abstract: 673,845. Pencil holders. DEHN, S. G. (Stylofede Corporation). May 2, 1949, No. 11671/49. Class 146 (iii). In a propelling pencil of the kind wherein leads are fed automatically from a storage compartment to a lead-feeding mechanism operated by pressing the pencil point against a writing surface, the leads being  successively advanced by depressing a portion of the pencil housing while the point presses against  the writing surface, the housing containing a slidably mounted lead feeding mechanism, the mechanism is provided with a split leadreceiving tube having fingers at either end, and an upper and lower gripping mean s each coacting with the lead-receiving tube to cause the lead-receiving tube to grip a lead, the lower gripping means consisting of a lower sleeve slidable on the leadreceiving tube, the sleeve having a tapered bore for flexing the lower fingers of the lead-receiving tube, both the gripping means being operably connected by an actuating lever system to grip and release the lead. The pencil comprises a casing 2 provided with a point section 6 accommodating a slidable point housing 10 urged downwardly by a spring 14 abutting against a flange 12 on the housing 10 and a shoulder of a bush 5 screwed into the casing 2. The bush 5 carries a bifurcated link 34 mounted on stub shafts 36, the links being connected to pivotally mounted levers 30 by a shaft 32, the levers 30 being also connected to another bifurcated link 40 by a shaft 38. The link 40 is connected by shafts 42 to a flanged clamping sleeve 44 having a tapered bore and being slidable along a split tube 46. The point housing 10 is screwed to the lower end 9 of a tube 8 slidable in the bush 5 and secured to the levers 30. A clamping sleeve 48 provided with a tapered bore and slidable along the lower end of the tube 46 is urged upwardly by a spring 59 interposed between a shoulder 56 in the housing 10 and a flange 60 on the sleeve 48. Downward pressure on the casing 2 when the pencil is in the position shown in Fig. 6, and held against a rigid surface, causes the tube 46 to be moved rearwardly against the spring 14 which acts through the flanged sleeve 44 and the lever system, the sleeve 48 also moving rearwardly against the spring 59. When the housing 10 abuts the surface, the tube 8 and housing move upwardly with respect to the bush 5, thus causing the lever system to raise the sleeve 44. When the sleeve 48 reaches a shoulder 64 of the tube 8 the upward movement of the tube 46 and sleeve 48 is arrested, thus allowing the sleeve 44 to move upwardly with respect to the tube 46, so releasing spring fingers 72 which grip a lead 69. Wings 76 on the tube 46 then abut against a flange 78 on the sleeve 44 causing the tube 46 to move upwardly with the sleeve 44 and relatively to the sleeve 48 such that fingers 70 release a lead 50. The leads 69 and 50 are then free to drop under gravity until arrested by the rigid surface. If the sleeve 44 is gripping the tube 46 harder. than the sleeve 48 when the sleeve 48 reaches the shoulder 64, the tube 46 continues to rise with respect to the tube 8 until a flange 66 abuts against a shoulder 68, thus checking the movement of the tube 46 with respect to the tube. Since the sleeve 44 moves upwardly with respect to the tube 8 by reason of the lever 30 and links 34 and 40, the sleeve 44 must move relatively to the tube 46, thus causing the fingers 72 to release the lead 69. Pressure on the pencil is now relaxed, so causing the bush 5 to move upwardly urged by the spring 14 with respect to the housing 10 and tube 8. The lever 30 displaces the flanged sleeve 44 downwardly, thus pulling the sleeve 44 over the tube 46 while forcing the split tube 46 into gripping position within the sleeve 48. The leads 50 and 69 are then carried downwardly causing the lead to project beyond the tip of the housing 10. As the lead 50 is worn away and successively projected in the tube 46, the lead 69 diminishes in height above a flange 82, thus allowing a further lead 86 to drop in behind the lead 69.