US1997496A - Propelling pencil - Google Patents

Description

April 9,1935." N NAGY 9 1,997,496

PROPELLING PENCIL Filed Aug. 16, 1933 Fig .13. Figl'l;J5 Figj'i. Fi g 16,

5 (A. "z FI im f@ 'f Patented Apr. 9, 1935 UNITED STATES PATENT OFFICE V1,997,496 Y rnoPELmNG PENCIL Nndor Nagy, Budapest, Hungary, assigner to' firm: Koh-i-noor Bleistiftfabrik L. & C. Hardtmuth, Bohm-Budweis, Czechoslovakia Application August is, 193s, serial No. 685,443

In Hungary August 22, 1932 s claim. (cl. 1go-rz) My invention relates to a propelling pencil which is simple in design, inexpensive to make and very easy to operate. The propelling pencil l of the invention resides in the possibility of concealing the lead -in the outer shell if desired and propelling it for use by a simple operation, a protective cap therefore being unnecessary. l

In the propelling pencil according to my invention, the feeding of the lead is not effected, as more usual, by rotation but by depression of a cap provided on the rear end of the instrument. According to the invention, this movable'cap is connected to or integral with the extremity of a feeding tube slidable in the outer shell or barrel ofthe pencil and urged rearward byaspring. The feeding tube' is cylindrical and provided o n its inner wall along a generating line of the cylinder with ratchet teeth. These teeth cooperate with a resilient projection or4 tongue of a cylindrical feeding rod s lidable in a guide tube mounted in .the pencil. This guide tube projects into the feed-- ing tube and is slotted along a generating line in order to allow the tongue of the feedingrod to project beyond-this tube and to engage the inner wall of the feeding tube. If the feeding tube is shifted forward by pressing a nger upon its protruding rear extremity, the resilient tongue of the feeding bar'orrod is engaged by the teeth 85, and the feeding rod is moved forward and the lead propelled. L

"1f the pressure Vexerted upon the end of the feeding -tube is relieved, said tube is moved back to its initial position by a spring; thefeeding rod. will not follow this rearward movement because of the friction in the guide tube and its tongue will engage-another ratchet tooth. 'I'he ratchet teeth on the inner surface of the feeding tubeare preferablyof arcuate cross-section in order to make it-'possible to bring 'the tongue of the feeding rod in and out .of engagement with said teeth by rotating said rod relative to the feeding tube. Thepencil is further improved by providing a longitudinal fin or ribin the guide tube engaging a recess of the feedingrod and llocking the latter against rotation. 1n this case, the lead is also providedwith a longitudinal recess and also locked against rotation. 1. The invention will now be fully described with reference to, the accompanying drawing, in

4of Fig. 8 v(viewed from the rear end).

winch: Fig. 1 shows the whole structure in an axial section, the front portion being designated Vby E and the rear portion by H. Fig. 2 is an end view of the rear portion, Fig. 3 a cross section of the lead, Fig. 4 an axial section ofthe guide tube, 5 Fig. 5 a cross section of the same, Fig. 6 a side view and Fig. 7 an end view ofthe tapered extremity of the guide tube in an enlarged scale. Fig. 8 an axial section of the feeding tube, Fig.

9 a cross section of the same along line 9-9- of l0 Fig. 8, Fig. 10 alike section along the line Ill-I0 Fig. 11 is an axial section of the outer shell or barrel Fig. 12 is a section on the line I2-I2 of Fig. 11. Fig. 13 shows the spring. Fig. 14 the end cap l5 in axial section. 'Figllthe same cap in cross section on the line |5-W of Fig. i4. Fig. 16 is a side view of the feeding bar. Fig. 17 a section on the line I1-I1 of Fig. 16. and Fig. 18 is a sectional view on the line I 8-I8 of Fig. 16.

The lead is cylindrical with circular cross section and provided along itswhole length with a recess or groove 8 engaging a rib or iin 9 protruding from the inner wall of the' guide tube 2. Thus, the lead is movable back and forth but 25 cannot be rotated. v

The guide tube 2 bears a ilange IU abutting upon a shoulder in the bore* of the outer shell or barrel l. Flange I0 may be dispensed with if the guide tube 2 is secured by means of adhesive or 30 in any other 4suitable manner in the interior of the tapered end of the barrel. The front end 2a of the guide tube 2 has greater outer diameter and'is slottedat I2 (see Fig. 6). The other portion of tube 2 extending rearward from flange Ill 35' has somewhat smaller outer diameter and is provided with a longitudinal slotL I4 opposite to the rib'9. This slot lallows the tongue I5 of the feeding rod 1I to pass. The front end of tube 2 is made resilient by the slots I2 andprevents 40 any lateral movement of the lead-i inserted into tube 2. f

Y The interior wall surface oftube Sis provided along itswholeV length, but only'over a part of itscircumferenca with notches cut into the-wall ,tends over `part of the outer circumference of tube -3 only (see Fig. 10) in order to limit theronauon-of tube s; the ends Ala or said aange engaging a boss provided on the interior wall of the closing cap 6 (as shown by Figs. 14 and 15a) Thus it is possible tovbring the tongue i5 by a short rotation of the feeding tube 3 into and out of engagement with the teeth I6. In order to facilitate rotation of the tube 3, the rear end 20 of the same, protruding from the barrel 4 and passing throug'li the rear end of cap 6 is milled at 20a.

Spring 5 bears with one of its ends against the end 24 of the ban-ell. Its other end presses flange I1 of the feeding tube 3 continuously against the inner ends 2i of cap 6. This cap' is secured on the rear end of the barrel 4 made of wood or any other suitable material and preferably of octagonal shape. 'Ihe barrel is bored centrally and split in two like parts which after insertion of the guide tube 2 are united by means of adhesive or in any other suitable manner.

'I'he feeding bar 'i is made of spring steel and has circular cross section in its front portion while its rear portion is prismatic and forms the tongue or projection i5 engaging with its end the teeth I5. The middle portion of bar l is slightly reduced to ensure light and smooth spring action against the ratchet teeth it. The cylindrical part of the feeding rod is provided with a groove 22d corresponding to the groove 8 of lead i.'

The propelling pencil according to the invention is operated as follows: First the lead iis inserted into the guide tube 2, care being taken that rib 9 of the latter engagesthe recess 8 of the lead. Then the feeding bar l is inserted, with its cylindrical portion directed against the tip of the pencil, into the guide tube 2 in such a manl ner that the rib 9 of the latter engages the recess 22a. The tongue iS'extends through slot id of the guide tube and engages the inner surface of the feeding tube. Now the operator grasps the milled end 20 of said tubeand turns it, bringing the tongue I5 of the feeding bar 7l into engagement with the teeth of the feeding tube 3. After this is done, the rear end 2010i Ythe feeding tube 3, protruding from 'the barrel ii, is pressed into the latter with a finger, in order to move the front edge25 of tube 3 into the space left between said end and the iiange l0 of tube 2. (See Fig. 1). By

this movement, the feeding rod 'I engaging with its tongue the ratchet teeth I6 and also the lead I are fed forward. If the nger pressure is relieved, spring 5 moves the feeding tube, bacio1 wards. During thismovement the tongue I5 slides over the ratchet teeth i8 and engages another tooth of the rack. Any backward movement of the lead I during writing is thus-made impossible. If the operation just described is repeated, the

- lead is successively propelled and may be used up until a very small residue is left, the feeding `tube being providedfsubstantially along its whole length withratchet -teeth.

, If it is desired `to push the lead I entirely back into the guide'tube 2 or if a new leadisto be inserted, it *isonly necessary to turn the milled end of tube 3, .thus bringing the resilient tongue I5 of the feeding bar 'l out of the rack teeth I6. If this is done, the vlead may be pressed into the tube 2 with the finger or otherwise. The tongue I5 slides in this case along engagement withY The embodiment of the invention as shownV a offers the advantage that the feeding bar is positively guided and any possible clogging of the tongue I5 is avoided.

What I claim is:

l. In a propelling pencil a guide tube provided with a longitudinal rib projecting from its innerl wall receiving the lead having a longitudinal groove, said guide tube being securedto the front portion of the barrel, a feeding tube arranged within the barrel and surrounding said guide tube, said feeding tube being movable from outside toward the tip of the pencil against the action of a spring and a feeding bar having a longitudinal groove engaging said rib ot the guide tube, said feeding bar being slidable in said guide tube extending with a resilient tongue through alongitudinal slot of said guide tube and engaging with said tongue the inner-wall of the feeding tube.

2. In a propelling pencil a guide ltube provided with a longitudinal rib projecting 'from its inner Wall receiving the lead having a longitudinal groove, said guide tube being secured to the front portion of the barrel, a feeding tube arranged Within the barrel and surrounding said guide tube, said feeding tube being movable from outside toward the ,tip of the pencil against the action of a springend a feeding bar having a lon gitudinal groove engaging said rib of the guide tube, said feeding bar being slidable in said guide tube, extending with a resilient tongue through a longitudinal slot of said guide tube and engaging with said tongue the inner wall of the `feeding tube, said inner wall being provided along its Whole length but only over a part1 of its cir'- cumference` with ratchet teeth of varcuate crosssection.

3. In a propelling pencil a guide tube provided 'with a longitudinal ribrprojecting from its inner wall receiving the lead'having a longitudinal groove, said guide tube being secured to the front portion of the barrel, a feeding tube arranged within the barrel'and surrounding said .guide tube, said feeding tube being movable from outside toward the tip of the pencil against the action of a spring and a feeding barlhaving a longitudinal groove engaging said rib of the guide tube, said feeding bar being slidable in said guide NNDOR NAGY.

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