US1853042A - Pencil - Google Patents

Description

F. C. DELl ET AL April l2, 193.2,

PENC IL Filed Feb. 2, 1931 .-lwwmm [film n WN NN NNWNQW WW mm. NM1

d QN! QN, EN NN MN WN., SNT

Our invention relates to Vniechanicalfpen- Patented Apr. 12, 1932 rnzimlziwo; n-nlzrfwintiair D. Gaosncnesn. erin WILLIAM Ii. ro'frrr, or `einentrici, y ILLINoIsvAs'sIeNons.'ro AUroPoIii'r COMPANY, or CHICAGO; ILLINOIS, AConrolm'rioironl ILLINOIS f reims.'

tentation sied YFebruary 2, 1931'. serial No: 512,806.

cils and more particularly to a pencil of theY propel-repel type.

llt is well-known that a number of ineohani# cal pencils of this Ageneral type have beensubmitted to the trade rand have enjoyed varying degrees of. successv dependent' on the respective eiiiciencies of the respective pencils. However, it has been'iound that pencils ofthistype are relatively expensive to manufacture and assemble and the cost thereor1 prohibits in a measurethe commercial success thereof. Y

It isan object of our invention to provide -a."pr,opel'repel vpencil'of a relatively inexf pensive construction yet thoroughly eiiicient and readily simple tok assemble.

A further object of our invention is to provide a novel safety zone at each end of the 3' movement of the luno'er to revent 'amming and injury to the 'plunger and associated parts often-resulting from imperfectly adjusted mechanism. f

OurV invention will be more readily lun- 5 derstood by reference to the accompanying drawings, in which:

Fig. 1 is a longitudinal sectional view of a pencil constructed in accordance with our invention f Fig. 2 is a fragmentary longitudinal sec-L tional view of a modied orm of ythe rtip construction n Fig.l 3 is an enlarged fragmentary elevation of theupper end of the outside resilient tube, and I 'Fig .11 is an'endelevation thereof.y

By reference to the vaccompanying' drawings, it willbe seen that our inventioncornprises the'frustoeconical ferrule 10, including the tip, the large end of which overlaps rotatably thevreducedy portion 11a of the bar-` rel 11.A In-the'small end of the tip 10, there is an opening 12, sized to allowthe passage therethrough ofa writing lead, not shown, oflimited diameter.

' The: lead chuck 14cons'ists of a ,tempered errule, Awhich is slotted longitudinally and slightly reduc,edzatthe openv end to receive A without shaving;` andto hold under tension,L leads of a limited variatinin diameter. The

eXtreme forward movement is limited bythe shoulder 12a. The outer end of the lead Vchuck 14 is langed internally asv at 15,l to

provide a stop for the head 16al of the plunger 16, and also as a Vseat for the coil spring 17. The plunger 16 is reduced in cross section for a determinate distance at one end so as to permit the free `sliding' thereof in the anged aperture 15 of the lead chuck 14, and to receive the coil spring 17. rThe plunger is enlarged at the lower end to provide the head 16a to prevent the withdrawal thereof rointhe chuck 14. At the other end of the reduced portion of the plunger 16 is pro vided a washer 19, as a seat for the coil springV 17.. This washer 19 in turn seats againstthe shoulder provided bythe thicker, threaded portion 2O of the plunger 16. This threaded portion 2O continues for a determinate distance to a point near the opposite upper end of the plunger 16. From thisr point, the plunger 16 is reducedy in cross section as at l21 to provide a'safety zone to be later described. rAt the: rupper extremity of the luno'er 16 thereis formed a flat or non'- circular portion 22, for cooperation withithe non-circular lportion-,23 in the plunger recess 24 iii the upper, non-circular portion of .the barrel, whichppermits the'plunger 16 to slide longitudinally in the barrel, butpre- Vvents rotationtherein.

Around the lead chuck 14, coil spring and plunger 16, we have provided the plunger guide tube 26, tapered at one end as at 27 to conformI to the'tapered wall oi' the tip 10 to which it is immovablyattachedby fstakingvp in the washer 28 against the side walll of the tipy 10. This staking in operation tightly wedges the washer in between the tip lOanel` the guide tube 26,y and ispermanently' secured by displacingsoine of the' metal from the wall of the-tip 10 inwardly over the top surfacey of the washer,fas shown at 29, andv also slightly deforining theL contacting surfaces as'shown at`30; This feature iis'not important herein, asit'iscovered'by'the cro-'pending application of `Frank C. Deli, and William F; Foth, filed August 25,' 1930, Serial No.- 477,625. f

A's best shown in Fig; 1,theguide tube 26 is of reduced cross section at its upper end and internally threaded as at 31, to conform to the threaded portion 20 of the plunger 16. Around the plunger guide tube 26 is provided a tubular, slidable friction sleeve 32, the forward end of which abuts a thrust washer 33 which rests against the staked in washer 28 in the tip 10, and the upper end of the friction sleeve 32 abuts another thrust washer 34 which rests against the tension collar 35 formed over the reduced end of the guide tube 26. At this end of the friction sleeve there are formed a pluralityv of transverse, parallel slots 36 extending preferably more than one-half the circumference of the sleeve, and alternately opposite, as shown in Fig. 3. These slots give a spring-like resiliency to the sleeve when it is compressed axially. The sleeve is held under slight axial compression by the tension collar 35 formed over the upper end of the lead guide 26 and held in place by spinning over a portion 35a of the metal of the lead guide 26. It has been found desirable to reduce the outside diameter of the friction sleeve 32, and increase the inside diameter to insure against the contact of the sleeve with the lead guide 26, and to allow for the partial closing of the resilient portion provided by the slots 36. The unreduced portion constituting the greater length of the sleeve 32 is intended to tightly contact the walls of the circular portion 25 of the barrel, and the plunger guide tube 26 and connected parts are permitted free rotary movement therein.

The purpose of the spring resiliency provided at the upper end of the rotatable sleeve 32 is to restrict the axial movement between the friction sleeve 32 and the guide tube 26, and to compensate for the wear of the thrust washers 33, 34 by longitudinal expansion of the sleeve 32.

In Fig. 2 we show a modification of the tip construction, shown in Fig. 1. In this form the operation of the pencil is identical with that previously described, except for mechanical substitutions arising out of the formation of a molded tip instead of a hollow metal tip as disclosed in Fig. 1. As shown in Fig. 2 we provide a conical metal tip 37, the lower end of which has an aperture 38 and internal shoulder 39, and the upper periphery of which is bent inward to provide a flange constituting the anchor 40, which is imbedded within the molded portion. 41 comprising the balance of the tip. The molded portion 41, serves the purpose of securely joining the plunger guide 42 to the tip 37. The molded portion 41 is also provided with a sleeve 43 adapted to overlie the lower end portion 45 of the barrel 46. The base of the opening provided at the upper end of the molded tip has a washer 47 and superposed thereon a thrust washer 4S against which the slidable friction sleeve 49 t is adapted to bear. In all other respects the structure comprising this form is substantially similar to that previously described and shown in Fig. 1.

The operation of the pencil herein described is substantially as follows. The pencil is taken with the tip in the left hand and the barrel in the right hand in the form shown in Fig. 1. The structure shown in the drawings is in a loading position and ready for insertion of a lead, not shown. Assuming a lead to be inserted through the open lower end of the tip 10, through the opening 12, it will be grasped by the lead chuck 14. Thereafter a rotation of the barrel to the left or counterclockwise while the tip is held firmly, will serve to draw the plunger 16 backward, because the non-circular head 22 is caused to slide longitudinally in the upper non-circular portion of the barrel. The lead is therefore retracted by reason of the pull of the plunger head 16a against the flange 15 of the lead holder. When the plunger has been retracted to its limit, the threaded portion 2O will be permitted to pass upward and out of the threads 31 in the upper end of the guide 26, thereby permitting the non-threaded portion 16 to pass into the threaded opening 31. Thereafter no further movement of the plunger backward may be had. However, the pressure of the spring 24 bearing against the flanges 15 of the chuck, and the washer 19 bearing against the lower end of the threaded opening 35, will cause the threads at the lower end of the threaded portion 20 of the plunger to be in constant contact with the threaded opening and ready for admission as soon as the rotation of the barrel is reversed to a right handed or clockwise Inovement, in which case the threads will again enter and the plunger will be moved forward to the position shown in the drawings. Thus it will be seen that when retracting the plunger a safety Zone is provided to insure against amming or damage to the parts when the plunger has reached its maximum return.

Assuming the. plunger is being propelled forward, the headed portion 16a will be projected forward until the threads 20 pass through the threaded portion 31. Thereafter further rotation of the barrel will cause the non-threaded portion 2l to enter the threaded opening 31, and thus no further forward movement of the plunger will be permitted. In such position the head 16a will be permitted to slide forward in the chuck and appear at approximately the end of the tip l0. The pressure of the spring 17 will likewise in this instance force the plunger backward, and the threads at the upper end of the plunger will be in readiness to be received in the threaded opening 31 upon the reversal of the rotative movement of the barrel. Thus it will be seen that we have provided a safety Zone for the plunger at both ends thereof to prevent injury to the parts.

lll)

lIlO

'circular in crosssection, a tip and attached tube, the tube having a threaded portion, a

lthreaded plunger cooperating with vsaid threaded tube and having a portion adapted to slide without rotation in the non-circular portion of the body, a chuck connected to the lower end of the plunger, a spring carried by y and movable with the plunger, the arrangement ot the threaded portions of the tube and plunger beingesuch that the threads of the plunger may be disengaged from the threads of the tube at both extremities of the plunger threads and that said spriiigurges Y said plunger into reengagement upon reverse rotation of the parts.

2. In combination, a pencil body having an axial recess, a-portion of which recess is noncircular in cross section, a tip and attached tube, .said tube having `a portion thereoi1 provided with an internal thread, a threaded plunger adapted to move within said tube, and to cooperate withthe threads therein, said plunger having a Vportion adapted' to slide without rotation within the non-circular portion of said barrel, a lead chuck connected to the lower end of said plunger, a coil spring carried by and movable with said plunger, therelative lengths ot the threaded portions on said plunger and said tube being such that the respective threads will become disengaged at both the extreme limits otlongitudinal movement, and will be rei-engaged due 'to the tension of saidcoil spring, upon the reversal of the relative rotationot' the parts. Y v 'p 3. In combination a pencil body having an axial recess, the upper portion of which recess is non-circular in cross section, a tip and attached tube, said tube -having a portion atA the upper end thereof provided with an internal thread, aV threaded plunger adapted to move within said tube, and to cooperate within said tube, andk to cooperate with the threads therein, said plunger having a noncircular portion adapted to slide without ro-` tation, within the non-circular portion of said barrel, a lead chuck connected to the lower end of said' plunger, a coil spring carried by and movable with said plunger, the relative lengths of the threaded (portions on said plunger and said tube being such that y the respective threads will become disengaged at both the extreme limits or longitudinal movement,.andwill be reeengaged dueto theY tension of said coil spring, uponthereversal of the relative rotation of the parts.

4. lncombination, a pencil body having an axial recess, a tip, atube lixed to the tip,

lead'advancing meanscarried by the tip and tube, a' sleeve immovably fixed within saidI recesstand joined to said tube with capacity tor relative rotation without relative longitudinal movement-with respect thereto, and

spring means. between the sleeve and -tube e adapted to effect a constant trictiona-l contact between the relatively rotating parts.

5. In'conibination, a pencil body having an axialv recess, the upper'poition of which is vnon-circular in crosssection, atip, a tube ixed tothe tip, lead advancing means including Va plunger, carried by said tip and tube, a sleeve disposed over said tube and having capacityf for Vrotation without .longitudinal movement relative thereto, and being adapted to vbe iixed within vthe circular portion in said' barrel, and spring kmeans between the sleeve .and tube adapted to effect a constant frictional contact between the relatively rotating parts.v y

. 6. ln combination, a pencilbody having an axial recess, the uppergportion of which is knon-circularincross section, a tip, a tube ixed to the tip, lead advancing means including a plunger, carried by said tip and tube,V 'the upper extremity of said plunger being non-circular in cross section and adapted to move longitudinally without rotation within the non-circular portion in said barrel, a sleeve disposed over said tube and having capacity for relative rotationwithout relative longitudinal movement, and being adapted to be fixed within the circularV portion in' said barrel, and spring means between the sleeve andy tube .adapted to effect aconstanttrictional contact between the relatively rotating parts.

In a pencil, the combination of a body ot moldable materialy having an axial recess, the upperportion otwhich is non-circular in cross section, and alead operating assembly, said assembly including a tip, a. tube xed thereto, having a portion thereof internally threaded, a plunger, said plunger having threads on a portion thereof for cooperation with the threads in said tube, the upper end of said plunger having a non-circular portion normally adapted to slide longitudinally without rotation with the non-circuanv 'its

lar portion ot said body, anda sleeve rotaty' able on and longitudinally immovable relative to said tube, said lead operating assembly being adapted to be operatively associated with said body by the sole act ot forcing said sleeve into the recess in said body.

8. In a pencil, of the character described,

the combinationY of a body having an axial'.

recess,'a portion of which'is non-circular in cross section, and a lead operating assembly includin a tip, a tube fixed to said tip and having t e upper' portion thereof internally threaded, a headed plunger having a portion thereof threaded for operative cooperation with said tube, a friction sleeve rotatable on and longitudinally immovable relative to said tube and having an external diameter substantially equal to the inside diameter of the. recess in said body, said lead operating assembly being adapted to be operatively associated with said body by the sole act of forcing said friction sleeve into said recess.

9. In combination, al pencil body having an axial recess, a tip, a tube fixed to the tip, lead advancing means carried by the tip and tube, a sleeve, a portion of which contacts the Walls of the recess to be rigidly retained Within the recess and another portion of which is relatively free from engagement with the Walls of the recess, means on the tube providing a thrust bearing between the tube and free portion of the sleeve with capacity for relative rotation, and spring means in the free portion of the sleeve adapted to efl'ect a constant fri ctional contact between therelatively rotating parts.

10. In combination, a pencil body having an axial recess, a tip, a tube fixed to said tip, the upper end of said tube being reduced in cross section and having internal threads formed therein, a collar fitted over said reduced portion, lead advancing means carried by said tip and tube, including a plunger, a portion of which is threaded and adapted for cooperation With the threads in said tube, and a friction sleeve having an outside diameter susbtantially equal to that of the recess, said sleeve being rotatable on said tube, and having its upper end bearing against said collar, and spring means between the sleeve and collar adapted to restrict the longitudinal movement of said sleeve on said tube.

In testimony whereof We have affixed our signatures.

FRANK C. DELI. WILLIAM D. GROSECLOSE. WILLIAM F. FOTH.

Images