US1879736A - Pencil - Google Patents

Description

F'. c:A DEU Sept 27, 1932.

PENCIL Filed April 18, 1929 WHA .NN QN NN QN QN @Si NN or v Patented Sept. 27, 1932 UNITED STATES- FRANK o. DELI, or eHIoAGo, ILLINOIS Application led April 18,

a pencil that will insure a fixed frictional re sistance to rotation without the use of the if common interiitting relation of a metal sleeve and a non-metallic cylinder. Due to the nature of the materials and to climatic changes in dierent parts of the country, the interiitted rotating parts frequently become either 25; loose or too tight. In the construction here proposed this is avoidedoand the frictional resistance is secured by an original `distortion of the lead tube. y

A further object of my invention is to pro- 2:V vide a plunger that will function perfectly in a threaded lead tube, but being formed without cutting threads therein, thus strengthening the plunger and removing the possibility ofdamage thereto in the event of jamming of the lead.

The invention will be more readily understood by reference to the accompanying drawing, in which Fig. 1 is a longitudinal sectional view of a pencil constructed in accordance with my invention; Y

Fig. 2 is a cross-sectional view taken on the line 2-2 of Fig. 1;

Fig. 3 is a plan view of the plungerutilized in my construction; and

Fig. l is a fragmentary longitudinal sectional view showing the tip extending to the head of the tube.

By reference to the drawing, it will be iii seen that my invention comprises the barrel 10, having a circular axial opening 12 in the lower end, which merges into a non-circular portion 13. A cap 14 and aneraser 15 close `an upper axial opening 11.

59. The circular opening 12is adapted to re- :PENCIL 1929. Serial No. 356,233.

ceive the bowed spirally groovedlead tube 16 having a non-metallic tip- 17 formed there-l on abutting the lower end of thebarrel. As shown in the drawing the part 17 is molded around the tube 16. The lower pointed ex-l 55 tremity'of the tube 16 is split to allow `for the commercial variation in the leads used `and to provide the necessary friction to prevent the lead from dropping out. In the form shown in Fig. 4, the tip extends to the end G0 of the tube, but experience has shown that the expansion of the split tube is so small that the progress of a lead therethrough is not materially impeded byconfining the tip.

u The plunger 18 is provided with the flat- YG5 tened portion 19and thebends or laterally deflected portions20 and is adapted to be received in the tube 16, the bends 2O having the same pitch as the grooves lin the tube. Y The flattened portion 19 is received within ythe 70 non-circular opening13. As best seen in Fig. 1 the space 21 is provided between the upper end of the tube 16 and the end ofthe circular opening 12. This provides a neutral-.zone or safety space, as hereafter described.

v In operation a lead 22 is inserted in the upper end of the tube 16 and the plunger 18 is screwed into the tube a shortdistance. The tube and plunger may then be inserted into the barrel, the iiattened portion 19 ofthe S0 plunger occupying the non-circular portion 13 of the barrel. The barrel being then r0- tated with the tip held securely against movement, or vice versa,the plunger will be forced forward in the threaded tube 16, thusI advanc-l 85 ing the lead. It is obvious that when the portion 19 emerges from the non-circular portion 13 into the circular portion 12, further rotation of the Vtip or barrel will not yad- Vance the plunger, This,therefore,providesa 90 vsafety zone','and prevents injuryor damage to tie pencil when the lead thereinhas beenv use The tip and tube are suitably frictionally confined in thecircular opening 12 by reason 95 of a `slight ini-tialbowing of the tube 16 from end to end. l As the tube is forced into` the .circular axial p opening it. is. straightened andfthusdoes not interfere with the opera. tien .of ithe plunger and lead, ,However,c .the 10 ial alignment, whereby to insure frictional resistance to its rotation when entered in the barrel.

In testimony whereof I have ailixed Vsignature.

. lFRANK C. DELI.

cross-sectional area than if screw threads were cut therein. This therefore serves to strengthen the plunger and reduce the weight of the pencil.

' I cla-im:

l. In combination, a pencil body havingan axial opening, one portion of which is non-circular in cross-section, the lower end of the body being tapered, a slightly bowed threaded tubeand a plunger adapted to project into the axial opening, and a tapered body that; functions asia tip permanently fixed to the lower end of the tube and adapted to abut without interfittingwith the pencil body. K j

2. In combination, a pencil body having an axial opening, one portion of which is noncircular in cross section, the lower end of the body being tapered, a slightly bowed threaded tube and afplunger adapted toproject into the axial opening, and a tapered bod-y that functions as a tip permanently fixed to the lower end of the tube and adapted to abut without interfitting. with the pencil body,`

said tip and body. v- 3. In combination, a pencil body havingV an axial opening, oner portion of which is-non circular in cross-sectiomthe lower end of the body being tapered, a slightly bowed threaded tube anda plunger` adapted to project into the axial opening,-and a tapered body that functions as a tip having a'conformation at its upperend substantially that of the tapered end of saidbody permanently fixed to the lower end of the tube and adaptedtoqab-ut without interfitting with the pencil body. 4. In combination, a pencil body having an axial opening, one'portionof which is non-circular in cross-section,Av the lower end of-the body being tapered, aislightly bowed threaded tube and a plunger` adapted tofpro! ject into the axial opening anda tapered body that functions asa'I tipV permanently tube being rotatable on said fixed tothe lowerend of thev tube and adapted to abut without Yintertting withv thepencil body, said tip and tubebeing'retained'in said axial opening by reasonV of the VContact ofv thev bowed portion of said tube againstthe Walls of the circular portion of said opening.

5L Ina pencil comprising a barrel, aA tipl therefor at the writing end having a tapered portion, and a reduced sleeve portionv rotativelyengagedinsaidbarrel, said sleeve being` a of yieldable materialpformed 'withla portion thereof initially bent slightl'ywout of true ax#V

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