US2624317A - Pencil sharpener - Google Patents

Description

`Iam. 6, 1953 M.YTAL| 2,624,317

i PENCIL SHARPENER Filed sept. 7, 1949 v 5 sheets-sheet 1 Aiarneys Jan.'6, 1953 M. TALL. 2,624,317

PENCIL SHARPENER Filed sept. '7, 1949 s sheets-shed 2 ,45 I i@ v fNri/ENTOR. BY 91' L11/muzi v Aff/11726975 M. TALL PENCIL SHARPENER Jan. 6, 1953 5 Sheets-Sheet 5 Filed sept. 7, 1949 Alfani @ys atented jan. 6", 1,953

UNITED STATES PATENT OFFICE PENCIL SHARPENER.

Murry Tall, New Rochelle, N. Y.

Application September 7, 1949, Serial No. 114,310

(Cl. 1Z0-96) 20 Claims.

The present invention relates to pencil sharpeners of the type having rotary cutters operated by planetary gearing and adapted to be operated either manually or by an electric motor.

It is the general object of the present invention to provide a pencil Sharpener of the typevindicated, having improved means whereby the length and shape of the point on the sharpened pencil can be regulated to suit the type of pencilv and the manner in which the pencil is to be used.

More specifically, it is an object of the present invention to provide improved stop means of such construction that the clearance between the stop and the cutters of the Sharpener remains practically constant for all positions of the stop, whereby breakage of the pencil point and chewing of the pencil through accidental insertion of the pencil point between the stop and the cutter are prevented.

It is a further object of the invention to provide improved means including a dial for setting the stop at its various selected positions.

It is also an object of the invention to provide a stop device which can be operated either from the inside or the outside of the chips or grindings-receiving container or casing, and which is of arcuate form and of varying thickness, and is so mounted that successive portions thereof of increasing or diminishing thickness can be introduced between the cutters in a manner to present an increased thickness where a stub point is to be produced, andA a diminished thickness where a fine point is to be obtained.

It is a still further object of the invention to provide a reliable and simplified mechanism for operating the stop by way of a dial having an eccentric groove from which the stop is controlled.

An additional object of the invention is to provide an improved dial and pointer assembly associated with the stop, wherein the pointer is iixedly positioned above .the rotatable dial and is provided with a protuberance adapted to engage in a series of grooves or notches in the dial to indicate the position of the adjusted stop, the pointer being in sprung condition, so as to snap into the successive notches in the manner of a detent.

A still further object of the invention is to provide a pivoted adjustable stop of arcuate form which is so shaped that. in'all adjusted positions thereof, a stop surface is presented between the cutters which is substantially normal to the pencil point, so that a positive stopping action is provided andA danger of slipping Iof 'the pencil point along the stop eliminated.

Another object of the invention is to provide a pencil Sharpener having adjustable stop means wherein the stop means can be controlled by rotation of a knob outside of the casing and adjacent to the operating handle of the Sharpener.

Still other objects and advantages of the invention will become apparent from the following detailed description thereof.

The accompanying drawings illustrate a satisfactory embodiment of the invention. In said drawings,

Fig. 1 is a rear end view of a pencil VSharpener constructed in accordance with the present invention;

Fig. 2 is a side view thereof, partly in section;

Fig. 3 is a frontend view of the sharpener;

Fig. 4 is a detail of the base and is taken along the line 4-4 of Fig. 2;

Fig. 5 is a view taken along the line 5-5 of Fig. 3;

Fig. 6 is an enlarged view of the cutter mechanism and supporting frame therefor, with the adjustable stop and the mechanism for operating the same mounted on such frame, the view being partly in section;

Fig. '7 is a view along the line 1-1 of Fig. 6 looking in the direction of the arrows;

Fig. 8 is an end View of the structure shown in Fig. 6;

Fig. 9 is a view partly in section through a modified structure wherein the stop device is controlled from outside the casing;

Fig. 10 is a view of the dial for indicating the selected position of the stop;

Figs. 11, 12, 13 and 14 are sections taken, respectively, along the lines of lI-l l,l l2-l2, l3-I3, and Ill-I4 of Fig. 9; and

Fig. 15 is an exploded View of the stop adjusting and position-indicating means.

Referring to the drawings, wherein similar numerals and letters indicate corresponding parts, the reference character a indicates the base or support of the Sharpener which may be manufactured by die casting or otherwise. At its upper end the base is provided with a thread by means of which the casing or chamber b for receiving the wood shavings is detachably secured to the base.` At the front of the casing b there is supported the selector cV on a stub shaft d, the selector having a number of apertures e for receiving pencils of different diameters. The selector bears against a projection f and also against a spring-pressed ball g. This is adapted to be received in a series of circular depressions h on the rear surface of the selector c and acts as a detent to hold the selector in adjusted position. The base a is provided with an enlarged anchoring plate i which is of hollow construction and is provided interiorly thereof with a plate 7' which can be made to cooperate with a flange or plate secured, for example, to a table top for Securing the Sharpener to the latter. This flange or plate may be directly secured to a table top in spaced relation thereto or may form part of a clamp k which is Ysecured to the edge of a table or the like, as by means of a thumbscrew 1. However, if desired, the base may be secured to a table, desk or the like by means of screws passing through apertured bosses m integral with the base. The Sharpener can be operated by means of a handle n, in known manner.

Referring now more particularly to Rigs. 6 to 8,`

the numeral I indicates the rotatable shaft of the pencil Sharpener which is operated by the4 hand crank or by a motor (not shown). The shaftis journalledin a bearing I Ia (Fig. 2) cast integrally Withthebase a, of the Sharpener. The shaft is secured at its right hand end, as seen in Fig. 6, to a frame I3 composed of endmembers I4 and I'5 connected by bars I S 'and I'I cast integrallyY therewith. `Between the enjd members I4 and I5 are journalledV ajpair of Cutters I8,'w hicl 1 may be arranged with their axeslying in the same plane or in planes disposedat an acute angle to eachother.' At their `innerenlsgthe shafts of the cutters are provided with gears I9 which mesh in known manner with an internal gear 2Ilj(1 ig. 2, but not'shovvn in detail) xed to thejbase of the Sharpener. As will be apparent, upon rotation of the shaft I0, the frame I 3 willbe rotated about the axis of the shaftvhile. the cuttersla will have bodily rotationY about, the Same and, by reason ofthe 'engagement ofthe, gears I9. with the stationary internal gean 2 3, they will be simultaneously rotated about their own axes, as iswell understood in theart,

The. hilnlov'elistqn-rnecl1anism .0i the present invention 'is'` controlled f rQm; a, dial 2J .havinsin the. top 'Surface' theregfa lscrissi Qfgfriumhered radial notches 22, the same 'being .tenin `niiiriber inthe example illustrated. The diai is, rotatably mounted lipari a. studliwhichmay be. foref tterd into a suitable openillgiri. the frame bar I or may becast Aintegrally with the frame. It is preferably` provided with a shoulder 24 upon which the dial bears. Anindex o r pointer 25, provided withn @rectangular 's lot, receives the correspondingly shaped upwardl end o f the', stud 23, suchv endbeing thenrjstruck down over the pointer to secure the same inixedpositi'on on the stud. The underside ofthe pointer is provided with an elongated protuberanceV 25 vwhich may be created by suitably notching thepointer, such elongated protuberance beingadapted to be received in the successive notches or grooves 22. The pointer 25 is made of springmetal, such as a beryllium-copper alloy andv in its mounted positionv is in sprung condition', so that theprotuberance 26 `vwill produceV aclick as it enters the successive notches 22; thereby indicating that the stopis in the selected position.

The underside oi thefdial 2I is provided with an eccentric groovemZfI which receives the end of the shorterarmj 28j of a bell-crank lever 29 which is pivoted 'on afpin3lsuitably, journalled in a recess 3| in the barV I6. The bar is providedwithvan elongated slot 32'in which the bellcrank lever moves.fas Shown best in Fig. 6.

The longer arm 33 of the above crank lever 29, constitutes thestop member proper and as can be seen from Fig.' 7, is so positioned as to.

enter the wedge-shaped space between the cutters I3 at their left hand or inner ends.

AS indicated -by the dotted line position of the bell-crank lever 29 in Fig. 7, rotation of the dial 2i in clockwise or counterclockwise direction will move the arm 2B of the lever radially inwardly or outwardly, respectively. As this occurs, the stop arm 33 will recede into a narrower portion of the wedge-shaped space between the cutters or move intov the wider portion of such space. As the position of the stop 33 changes, the character of the point imparted to the sharpened pencil will likewise change, depending upon whether such point iS permitted to penetrate to the extreme. left-hand end of the cutters I8, or isstopped at a distance therefrom by the stop 33.

Accord-ing to a further feature of the present invention, the stop 33 is So shaped that as it moves into wider portions of the wedge-shaped Space between the. Gutters., it presents a wider surface' to the/penl pont for engagementthere- Wltlfl- All, the. Same, time.. the stop' takesv up .the increasingcle'arance between vthe cutters softhat the clearance between'the stop4 andthe two cutters Y remains. Substantially. .constant In. conse: quence, the danger of the pencil point being Caught. betweenftlie ,Stop andllleclltter, iselimi.- nated and` wasteful',chewingupiy of the pencil 1S pfefvelltlf .'-The S1591?. ,es'elvesigCentelr the perle. properly and; uiiiormsliarpenma is 0bemedf 1 1 Obtallllhe. inst described result .most Simply by. tapering' the Step in. Seth. manner that, its mistress llicreasesfiqzrl. itsjiree end, toward.' its fulcruin.v The degree of; taperY will depend upon the afluarlvof. th. alie Oltlle. tivo. Cutters, but in general the tl'iickness ofthe stop will vary. from about 0.025inch fronj nearA itsfree end, to about 0.062 inch at Ya'. point'about midway along4 its length, these guresrepresenting the thicknesses fthe realms engasedbymhe pencil point at the two extremes ofY adjustment of the stop; ni the illustrated embodiment Orth@ inf vention'the stop hasten' positions which are spaced about 02020 inch apartin thy axialf'directionof the''pen'cil.' I Y The stop 33is.H of arcuate form and thecurvature o f itssurface-in aplanfp 'sing through the axis of the pencilfis soV determinedthat Yin all positions of thestop, its lsurface is'substantially at :right 'mieles'` tp" 'die axis! ofjthe penbii' at th point Wheretlie pencil engages "stop By this construction, the'pen'cilishel v duringrthe"cuttingfdpeation, both when along and sharp point is desired, and the Stop isin'its fully retracted positionjowhena shorter stub point is sought, when thesto'p is" in its extreme opposite position, and also in all intermediate positions.

It Vwill be noted lthat by reason oli theengagement of the'shortr of the belli-crank lever, 0f which the S1501? forma rrtwitliin thelspn-ai groove, in the dial,4 af `positive kicking of the stop 4 ,e. d,andthere' isno danger thatpressurewlthjh pfricilon the stop will causedisplacementof the latter.. Also, the parts are'so constructed'and relatedthat equal angular movements vof thedial will produce substantially .equal displacements .ofjlthe? stop. It will b e apparent thatinplacenia .centrically' mounted ldial' having 'anfeccentric groove therein, a reverse arrangernent couldlbe employed-5'. that is, thermal could- ,be mounted cenaug and circular groove.

providedwith amore. 9;' nessiar1ca11vpositioned in xed position Y In use, the Sharpener above described has been found to provide a well balanced structure which prevents @breaking or splitting of the pencil andk provides better centering of the pencil with accur-atecontrol of the stop, device. Whether the pencil is yfed by hand or automatically by any known form of spring-controlled mechanism or the like, a uniform cutting of the pencils is obtained and chewing of the pencil is avoided.

In the mechanism hereinabove described it is necessary to remove the shavingsfreceiving casing before the dial for adjusting the stop device can be operated. In a fur-ther development of the invention I have provided a modied stop adjusting mechanism which can be controlled from outside the casing but which embodies lthe essential improvements of the structure shown in Figs, 1 to, 8. rI he modified pencil Sharpener structure is illustrated in Figs. 9 to 14. t Referring to such figures, the stop member is shown at 40 and is provided intermediate its ends with trunnions l4| .which are adapted to be received in an open transverse groove 42, the stop member-itself passing through a longitudinal groove 43 in the frame. The frame is countersunk as shown at 44 to provide a seat for leaf spring 45, the latter being normally retained within the countersink flush with the outer surface of the frame. The spring may be provided with a lip 46 extending at right angles to the body of the spring and received within a notch 41 at the lef-thand end of the countersink to aid in positioning and retaining the spring within the countersink. The anchored end of the spring can be secured permanently in position by staking over or striking down the metal at the edges of the countersink. It will be understood tha-t the free end of the leaf spring engages the shorter arm of the stop to the right of the trunnions, whereby increased leverage is provided and uniform` pressure is exerted on the stop. This construction also makes possible an easier movement of the adjusting knob to be described hereinafter.`

The stop member 40 is adapted to be engaged by a longitudinally movable rod 41 slidable in a suitable bore in the rotating frame I4 yand in the shaft 48, such bore being located above the `cen-- tral axis of the frame to enable the rod to clear the cutters which are set at an angle to each other. The shaft 48 as threaded is shown at 49.

The operating `handle n of the sharpener is provided with a hollow hub which is threaded as shown at v51.1 to engage the threaded portion 49 of the shaft. The handle is also provided interiorly thereof with a cylindrical stop which engages the end face of the first thread on the shaft 48 in such position that suilicient clearance is provided between the hub of the handle andthe boss 52 onthebaSe. a to enable the handle to be rotated freely, together with the shaft and the rotating frame.

Ihe rod 41 extends for a short distance, s-ay about 0.180 of an inch, beyond the left-hand end of the shaft and bears against the surfaceof a bushing ,53 which is provided upon its opposite face witha helical cam surface 54, which cooperates with a complementary helical cam surface 55 at the inner end Vof a knob 5B. The bushing 53 is provided with two keys 51, 58 which are rek ceived within diametrically opposite longitudinal grooves or key-ways in the hub of the handle, the bushing being thus free to move only longitudinally relatively to the'hub of the handle on its keys.. The knob itself is journalled in a, wash, er y59 which is Y,slipped over the end of the knob and'is locked in position against the edge of the hub by staking or striking down the metal at the edge of thehub over the outer rim of the washer. The knob is free to rotate relatively to the Washer and is provided with an index groove 60 to indicate the adjusted position of the stop, as will be explained more fully below. i

It will be understood that the rod is normally under the pressure of the spring 45 and in the assembled position of the parts, when the stop is in its most retracted position, the end of the rod just bears against the face of the bushing. Upon rotation .of the knob, the cooperating cam surfaces will cause the bushing 53 to move axially inward and thereby shift'the rod to the right (Fig. 9). This will cause rotation of the stop 40 on .its trunnions and the stop will be moved toward the ri-ght from an initial to a final position. In practice I Ahave found ten positions to be a convenient number for indicating the whole range of adjustment of the stop. As in the construction shown in Figs. 6 to 8, the thickness of the stop increases from its free end toward its fulcrum, which takes account of the fact that the space between the cutters increases toward the right. For the reasons given above, I prefer to make the taper on the stop correspond to the increasing distance between the cutters in these positions, so that the clearance between the stop and the cutters remains substantially constant in all positions of the stop` To indicate the different positions of the stop, I provide index numerals on the washer 59, the groove on the knobserving as a pointer to indicate the different positions of the` stop. To enable the operator to determine the different positions of the stop, that is, to indicate to him tactually the arrival of the stop at the successive positions, I provide a series of ten teeth 6I on a serrated collar 52 on the knob which are adapted to mesh successively with a similar series of crown teeth 62 on the serrated inside face of the washer; the knob being under the action of the spring, the teeth will mesh with a click. To provide thenecessary clearance to enable the ridges of the circular rows of crown teeth to pass each other as the stop is set at successive positions, the washer is staked down with -a clearance between it and the teeth on the collar 62 equivalent to about the height of the crown teeth. For this purpose a clearance of about .015" will ordinarily be suflicient. It will be noted that as the knob is set to different positions all of the crown teeth on the washer and on the knob will be in continuous engagement, so that the wear is reduced and binding is eliminated, and at the same time a uniform and even action is secured, which results from the fact that the helical cam surfaces engage each other over extended distances, so that here again wear isreduced and the life of the device increased.

The knob is provided with a stop 64 which is adapted to engage a corresponding lug or stop 65 inside the hub of the handle. The stops are so positioned that at the limit of movement in one direction the index groove will be opposite the number l on the washer 59 and at the opposite limit of movement it will be opposite the number I0 on the Washer.

It'will'be apparent that by operation of the knob, indexing and positioning of the stop occur simultaneously.

l. In a' pencil Sharpener, the combination with a pair ofl rotary cutters disposed with their axes at an acute angle toeach other, of an adjustable 'Stop for the point of apencil being sharpened therein, saidV stop being positionable along vthe central axis between vvthe cutters vandv movable transversely to-su'ch axis as its distance from the converging ends of the cutters, andai-ny the direction of the diverging end's'the'reof, increases, 'said stop being of increasing thickness transversely to such central axis corresponding approximately' to the increaserof theA clearance b'etweenthe cutters as the stop is adjusted topositions at' increasing distances from theY converging ends of the-cutters', whereby the clearance between the stop andthe cutters is maintained small and approximately constant' for 'all positions" of the stop along the central axis. y

2. A pencil Sharpener `as defined in claim 1, wherein the `Sto'p is of 'arcuate forni and 'is' 'of gradually increasing'- thickness' from one end thereof toward the other.

3'. In a pencil Sharpener, thecombination'. with a casing, a rotatable frame therein, a pair of rotary` cutters having theirV axis disposed atan acute angle to each other, said frame including a bar extending over the cutters and spaced from' the Vcentral axis of the frame, of an adjustable stop for the point of a pencil being sharpened, said stopv being mounted on said-bar and being movable between the cutters, andmeans for adjusting said stopand including a rotary member operatively connected with said stop and disposed on said bar.

4.'A vpencil Sharpener as dened in claim 3, wherein said rotary member comprises a `dial provided withY an eccentric'groove', and means engaging said". groove and connected with the stop.

5. AA pencil Sharpen'eras dened in claim 3, where'inthe'rotary member'c'omp'rises a dial hav'-l ing a series of indentations corresponding'with the different positions o'f adjustment'of thel stop, and' aH xed pointer cooperating with thedialand provided with a protuberance engaging vwithin the indentations. y

6L 'A pencil Sharpener as dened in claim 3, whereinl the rotary member comprises a; dia-l hav-v ing 'a series`A of indentations corres'pondingwith the different positions of adjustmentof the stop, and.axedpointer-cooperating with the dial and provi-'ded' with a protuberance engaging-withinthe indentations, the pointer being di'spos'eizlv above the" dial and being mounted'c'oncentrically;

'7. A pencil Sharpener as defined in claim 3, wherein the rotary member comprises a dial hav-- ing'a series of elongated, radial indentat'ion's, cor-l responding with the dinerent positions of adjustment of the' stop, i and a nxedpointer arranged above and cooperating with the dial, and provided with an elongatedprotuberance on its underside engaging within theY said indentations. n

8. A pencil Sharpener as defined in cla-iinA 3, wherein the rotary member comp'rises-a-dial hav'- ingv a vseries of indentations corresponding with the different positions of" adjustment'o'f the stop',

and a fixed pointer cooperating with-the dial and` provided with aprotuberance engaging Withinthe indentations, the pointer beingk disposedl above thedial and beingnorma-llysprung so as tocatch into the successive indentations as the dial isrotated.

9'. In a pencil Sharpener, the combination with a casing', arotatable frame therein, apair of rotary cutters mounted in the frame-for sharpening the point of a pencil, the frame includingabar eXtendingover/the cutters and spaced from the surface to the pointo'f'apen at ess'iveposilliloiis'- between the 'cutters and albngrfsad etral axis, and a ro'l'alfy'1rnerlleel'dsfsdA itefally of the casing' and operatively" associated `withA the stop member for adjusting the same' v'alngfsaid central axis. y

10'.A A pencil Sharpener as defined in claim 9', including a rode" 'g-gth arcuate rnenb'er afnd controlled bytl rotary il'litlll. A pencil -sharpene'r as de'ned in-.claifn'f 9, including a spring normally urging ythe sto'pmeniber' into an extreme position, and cana' elements controll'edby the' rotary frielrlzerQ and beariigfn the rod to move' the'saznieagfinS'tI-the action of the spring.. Y

l2. A5 pe'r'icil'sl'ni'rpe'n'erV asdened' in ca'iiin"v lll-, wheeinthecanl elements''are' providedlwith coinpler'ne'ntary helioal cam sr one ofthe-dani elements being mounted if raxial 'movement and held against rotary movement, While' Vthe` other cani-element is securedy to-the rotary meinben 13.--A pencil Sharpener as dled in claim 9, including a serrated `disc hel'd against rotary movement, and a correspondingly serrateddisc xed to the rotary member and engageable' with the rst disc to give a tactual indication o'f the arrival of the rotary member' ats'uccessive stop positions.

1'4. A pencil Sharpener' as'- de'ii'ned in claim 9, including" stop means'for' limiting'me movement of theA rotar-y member.

l5. A pencil Sharpener asl def-lined iii-claim 9, wherein the stop member'iS-ofarcuateshap'e and in the different adjusted position's thereofpre; sen'tsv surfaces which are substantially perpendicular-to the axis of the'pen'c'il.

16. A pencil Sharpener as dennen'v in claim 9. wherein the stop memberpresentsdifferentthicknesses at the different positions thereof to maintain its clearances between itself and the cutters substantially constant.

17. A pencil Sharpener comprising: a base, a' frame rotatable on `the base, 'cutters rotatably l mounted in the frame, said-'fram'ehavin'g a-sha-ft passing through the upper portion 'ofthe'base,a handleh'aving ahub'threadedly engaged-with the shaft, an arcuate stop member' pivo'tedA on the frame andv movable into different positions be tween the cutters and' along'th'e axisfo'frotation of the frame for engagementy by the'pe'n'cil point, a rod bearing on the stop and passing through the shaft, an axiallyv slidable 'cam' member having a helical cam surfaceand-.inounted `With-in the hub ofthe handle, arotatableknob closingthe outer end of the hub and provided with a comple'- mentary cam surface bearinguponlthe Vfirst mentioned cam surface to effect axial movement of thecam member'upon rotation of thefkfnob, a spring bearing upon the Stop member to urgethe' same into retracted position, a. stationarywasher' between the knob and the hub and provided with indexv numeralsand a mark' o'n'l the lin-ob' co' operating with said numerals to indicate' the successive positions' of .the'adjus'td stop.

18-.,A pencil sharpener as defir'i'edl in claim 17 wherein the rea-r Surface' of thewasher is's'errated, and a serrated collar on th'eknob andada'pted to cooperate with the serration on the' washerto give atactual indication of the arrival ofthe rotary member into successive-stop positions'.

19'. A pencil Sharpener as defined! in claim 17, wherein the. Stopy member' is of increasing! thicknessy toward its fulcrum'point' alonglthe'reg'ion centraliaxistthereof;*'foflaIstop:member mounted- 75m74 whichfentersbetweenzthe cuttersfwieby S'b" stantially uniform clearance between the stop member and the cutters is maintained in all positions of the stop member.

20. In a pencil Sharpener, the combination with a pair of rotary cutters disposed with their axes at an' acute angle to each other, of an adjustable stop for the point of a pencil being sharpened, said stop member being movable both along and transversely to the central axis between the cutters, said stop being disposed between the cutters and being of increasing thickness from one end toward the other transversely to the central axis and being so mounted that thicker portions thereof become disposed between the cutters as the stop" is progressively moved to positions more distant from the converging ends of the cutters and in the direction of the diverging ends thereof, whereby the clearance between the stop and the cutters is maintained small and approximately constant to prevent insertion of the pencil point between an edge of the stop and the adjacent cutter.

MURRY TALL.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS

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