US2338263A - Pencil sharpener - Google Patents

Description

Jan. 4, 1944. F. M. SCHAEFER 2,333,263

PENCIL SHARPENER Filed Feb. 20, 1941 45 a a a: 4 3 44 Patented Jan. 4, 1944 PENCIL SHARPENEB Frank M. Schaei'er, Chicago, 111., assignor to William G. Pankonin, Chicago, Ill.

\ Application February 20, 1941, Serial No. 379,789

15 Claims.

This invention relates in general to a pencil sharpener and has more particular reference to the cutters and the means for operating them.

An important object of the invention is therefore in the provision of improved cutters for sharpening a pencil and in the operating means for rotating the, cutters.

Other objects of the invention are in the provision of an improved casing for housing the cutters and the motive means therefor; to provide an improved chip receptacle and means for removably holding it in place; to provide an improved pencil centering device operative for pencils of all sizes; to provide an improved enclosing casing of novel construction and design; and in general to produce the construction herein shown and described.

In the drawing illustrating a preferred embodiment of this invention,

Fig. 1 is a side elevation of a pencil sharpener in accordance with this invention;

Fig. 2 is a sectional view of the structure shown in Fig. 1;

Fig. 3 is a section taken on the line 3-3 of Fig. 2; r

Fig. 4 is a section taken on the line 44 of Fig. 2;

Fig. 5 is a section taken on the line 5-5 of Fig. 2 showing one of the cutters; and

Fig. 6 is a perspective of a cutter supporting stem.

In pencil sharpeners as now commonly used the cutters are each made of one piece of material with spirally grooved blades which are both expensive and usually wear very rapidly so that v the sharpener breaks the lead of a pencil or does not point it properly after a short use. These pencil sharpeners are also usually provided with an operative crank by means of which the cutters are turned.

In the present invention the cutters are improved by making them of a plurality of toothed discs assembled upon an arbor or sleeve and the motive means consists of a pull string operating a ratchet drum equipped with a return spring. By this construction the cutter discs can be suitably hardened so that they will wear less and the discs themselves can be changed from time to time so that those which wear more rapidly can be replaced by others which are not so worn. A single pull oi. the string is usually suflicient to point any pencil and the spring recoil of the string always returns it within the casing.

Referring now more particularly to the drawing, a central standard or support 8 has a base 9 in which openings are commonly provided for attaching it to a horizontal or vertical support.

The outer portion of the standard provides a bearing bore ill for a cutter shaft or spindle II; a shouldered portion I2 at one side provides a circular seat for the inner end of an outwardly rounded casing l3; and an opposite circular projection i4 provides a seat for the inner circular end of a casing I5 which extends outwardly with an inwardly turned pencil opening It at its outer end. These two casing sections l3 and I5 together provide a somewhat streamlined outline of pleasing appearance rounded at one end and more pointed at the other.

A pair of cutters I 1 are mounted at an angle upon spindles Hi, the inner ends of the cutters being close together to provide a sharp point for a pencil. The spindles are inserted through outer ends IQ of a holder formed integral with or attached to the spindle shaft II which has a projection 20 near the bearing of the shaft into which the inner end of each spindle i8 is threaded.

To rotate the cutters a recess 2| is preferably formed in the standard and partially surrounding the spindle projection 20 and in the outer edge of this recess is seated a circular rack 22 having teeth on the inside. These teeth engage gears 23 carried by each of the cutters I'l so that as the spindle shaft II is rotated the gears 23 engaging the teeth of the circular rack 22 correspondingly rotate the cutter l'l. As each cutter is slightly inclined to the axis of the shaft II the gears 23 will be correspondingly inclined to the ring gear 22 but the teeth are in proper alignment to produce rotation of the cutters.

Each spiral-like cutter l! is preferably formed of a plurality of toothed discs 24. The discs 24 are substantially identical in size and configuration. In the preferred manner of construction they are punched out of thin metal stock and are subsequently heat-treated to harden their cutting edges. Each disc has a number of outer teeth 25 formed in the periphery of the disc. Each of these teeth presents a cutting edge when the disc is rotated in a counter-clockwise fashion, as viewed in Figure 5. The discs 24 have an inner or central opening provided with an internally projecting key 26. The discs 24 are concentrically arranged in laminated fashion on an ar bor or sleeve 28. The arbor 2B is provided with a groove 21 which describes a spiral, or, more accurately, a helical path on its surface. One end of the arbor 28 has a projection 29. To this projection the gear 23 is secured. When thediscs-24 are assembled on the arbor 23 they abut against the projection 23 and the outer ends l3 of the cutter support. In the assembly, the keys 23 of the discs 24 flt in the groove 21 and as each disc is substantially identical and interchangeable, the adjacent teeth of adjacent discs will be slightly uniformly angularly misalined to describe a spiral cutting path. Thus, as assembled, the cutter presents a plurality of spirallike cutting edges. To change the discs on any arbor its bearing spindle I3 is simply removed by unscrewing it, the cutter being then bodily removable and the discs being changeable by simply removing them from the free end of the arbor and replacing the worn discs with others which are not subject to such severe wear. Thus the cutters may in effect bereplaced or renewed and are capable of long life and hard usage without replacement of an entire cutter.

The shaft projection 23 is commonly provided I with a pencil point extension 23 the extremity of which is just at the point wherethe cutters i1 would meet if extended, thereby limiting the feeding of a pencil therein and preventing the formation of a long thin point to the lead.

In the casing l3 below the cutters is a chip discharge opening 33 and a chip discharge receptacle 3i is positioned below the opening and held releasibly but firmly in this position by an integral extension 32 which flts overthegradually reduced end of the casing, preferably having a portion 33 at the top and a perforated opening 34 at the end larger than the pencil opening 13 of the casing so that pencils may be inserted freely therethrough, the edge of the opening '34 being somewhat indented or turned inwardly so that this portion will also serve to center and maintain the extension 32 and. the holding portion 33 in place. Between these portions the material may be omitted, forming serrated or other decorative edges 33 as shown more clearly in Fig. 1, which add to the completed appearance of the entire device. Also by having the extension and the holding portion separated in this manner they will spring more readily in place over the casing i3 and will hold the chip receptacle 3i tightly in place at the bottom of the casing.

At the inside of the casing i3 and pivoted to opposite sides of the extremity of the casing which form the pencil opening i3 are curved guides 33, the inner or free ends of which are drawn together by a coil spring 31 which extends entirely around both guides or is attached to the outer sides of both of the guides. This guide tends to center a pencil of any size with respect to the cutters I1 and to hold the pencil yieldingly in place by the tension of the spring 31.

To rotate the cutters by means of the shaft ii a pull string ratchet mechanism is connected to the shaft at the side opposite the cutters. This comprises an end fitting 40. attached to the shaft by a set screw 4| and having a number of engagement notches 42 in a flange 43 at the end of the shaft. Freely rotatable on this end fltting 40 between the flange 43 and the shaft bearing formed bythe standard 3 is a winding drum. 44 preferably formed of sheet metal having an inner bearing portion 43 mounted on the member 40, an outer string receiving portion 43 with end flanges for preventing the string from running of! the drum and with a connecting portion 41 at the outer side of the drum. Pivoted to this connecting portion and overlying and in line with the flange 43 are opposite weighted dogs or assaacs latches 43 adapted to engage the teeth or notches 42 in the flange. The space under the drum and between the connecting portion 44' forms a container for a loosely wound coil spring 43 having one end attached to the drum by means of a screw 30 and the other attached to the standard 3 byascrewil.

A pull string 32 is attached at one end to the drum, is wound on the outer portion 43 thereof, and the extremity extends through an opening 33 in the casing 13. The extremity of the string is provided with a knob or button 34 which will not pass through the opening and therefore forms a flnger engaging means for the pull string and also limits th inward movement of the string thereby keeping it tightly wound on the drum. The casing I3 has a tightly fitting slip connection 'over the shoulder i2 and may therefore be rotated for positioning the opening 33 in any desired location, which requires some variation, depending upon the attachment of the device to a fixed support. The casing may also be removed for increasing or decreasing tension on the wind-, ing drum with respect to its spring 43.

In operation, assuming that the pencil sharpener is flrmly attached to a suitable support, and that the chip receptacle is in place, a pencil is inserted through the opening 13 which is' centered thereby with respect to the cutter II. The operator grasps the pull string knob 34 and pulls outwardly on the string, which rotates the drum and with it the shaft II by reason of the engagement of the weighted catches 43 with one of the notches 42, thus rotating the cutters so that their gears 23 engage the inner teeth of the flxed ring gear 22 and rapidly rotate the cutters against the pencil inserted. The pull on the string is reduced and the spring 43 is allowed to reversely rotate the drum, returning the string within the casing and winding it upon the drum until the knob I54 engages the opening in the casing. One pull of the string is usually suflicient to point any previously pointed pencil but a number of additional pulls may be made if necessary. In the return movement of the string the latches 43 are thrown outwardly and are moved in a reverse direction so that they do not engage the notches 42 and therefore the shaft II and the cutters I! are not reversely rotated, thus saving wear of all the parts.

The casings I3 and I3, as well as the chip receptable ii and its attaching parts, are represented as made of thin metal but may also be made of other material, either transparent or opaque, colored or clear, and may even b made of a molded condensite material such as Bakelite. The two casing sections are intended to form a substantially continuous ,outer surface separated only by a thin portion of the standard 3, presenting a novel and pleasing streamline outline.

I claim:

1. In a pencil sharpener, a support and a shaft rotatable therein and projecting to both sides thereof, rotatable cutters supported by the shaft at one side of the support, means for rotating the shaft at the other side of the support, a casing fitting over the mechanism and attached to Y the support having an opening for operating said rotatable therein and means for rotating it, cutters carried by the shaft at one side of the support, a casing secured to the support and extending over and beyond the cutters with a progressively smaller end having an inwardly turned extremity forming a pencil aperture, and means secured to the inwardly turned extremity within the casing to engage and center pencils of various sizes with respect to the cutters.

3. In a pencil sharpener, a support, .a shaft rotatable therein and means for rotating it, cutters carried by the shaft at one side of the support, a casing secured to the support and extending over and beyond the cutters with a progressively smaller end having an inwardly turned extremity forming a pencil aperture, a pair of guides pivoted at opposite sides of each extremity, and a spring tending to pull the guides together at their free ends for centering a pencil with respect to the cutters.

4. In a pencil sharpener, a support, a shaft rotatable therein and means for rotating it, cutters carried by the shaft at one side of the support, a casing secured to the support and extending over and beyond the cutters with a progressively smaller end and having a chip opening at the bottom below the cutters, and a chip receptacle to fit closely below the opening having an extension fitting over the said end of the casing for holding the receptacle tightly but removably in place.

5. In a pencil sharpener, a support, a shaft rotatable therein and means for rotating it, cutters carried by the shaft at one side of the support, a casing secured to the support and extending over and beyond the cutters with a progressively smaller end and having a chip opening at the bottom below the cutters, and a chip receptacle to fit closely below the opening having an extension from the edge of the receptacle extending over the end of the casing and also for a distance on the side of the casing opposite the receptacle to provide a flexible holder and retainer for the receptacle.

6. In a pencil sharpener, a support, a rotatable shaft, means at one side of the support for rotating the shaft, a pair of cutters and means for mounting them on the other end of the shaft at an angle to each other and rotatable with the shaft, means for directing and. holding a pencil for engagement of one end thereof between and by the cutters, each cutter comprising a plurality of similar discs with outer teeth and an inner key, an arbor on which the discs are mounted having a spiral groove engaged by the keys, and the discs being freely mounted and interchangeable on the arbor to replace worn discs at one location with other discs of the same cutter.

'1. A structure in accordance with claim 8 in which the shaft has a cutter carrying head with spaced projections at angles to the shaft axis, and a removable spindle positioned ineach pair of said projections upon which the arbor is mounted.

8.1napencilsharpenenacutter andmeans for rotating it, the cutter comprising a plurality of identically formed discs having cutting teeth on the periphery, and means for mounting the discs adjacent each other whereby adjacent teeth are slightly advanced angularly to form spiral cutting ridges with respect to the cutter.

9. In a pencil sharpening device, a main support upon which the device is mounted, an enclosing casing of somewhat oval shape also mounted on the support, the casing having an opening to receive a pencil, and a second casing mounted upon the first casing also having an opening for inserting a pencil.

10. In a pencil sharpening device, a main frame upon which the device is supported, an qrnclosing casing of somewhat oval shape, also mounted on the frame having an opening at one end to receive a pencil, and a second casing removably mounted upon the said end of the first casing having an opening through which a pencil is' inserted, and also having a bottom chip receiving receptacle.

11. In a pencil-sharpener, a spiral-like cutter comprising a plurality of substantially identical toothed discs concentrically arranged in laminated fashion, adjacent teeth of adjacent discs being slightly uniformly angularly misalined to describe a spiral path on the cutter, and means to secure said discs in said relation.

12. In a pencil-sharpener, a spiral-like cutter comprising an arbor having a spiral groove, a plurality of substantially identical discs having outer teeth and a central opening provided with a key, said discs being positioned in side-by-side relation on said arbor with their respective keys inserted in said groove whereby adjacent teeth describe a spiral path on the cutter.

13. In a pencil-sharpener, a spiral-like cutter comprising a plurality of toothed discs punched out to have the same configuration and be interchangeably alike, said discs being concentrically arranged in laminated fashion, adjacent teeth of adjacent discs being slightly uniformly angularly misalined to describe a spiral path on the cutter, and means to secure said discs in said relation.

14. In a pencil-sharpener, a spiral-like cutter comprising an arbor, a plurality of substantially identical toothed discs concentrically arranged in laminated fashion, adjacent teeth of adjacent discs being slightly uniformly angularly misalined to describe a spiral path on the cutter, and tongue and groove means of spiral configuration acting between said arbor and said discs.

15. In a pencil-sharpener, a cutter comprising an arbor, a plurality of toothed discs punched out to have the same configuration and be interchangeably alike, said discs being concentrically arranged in laminated fashion, adjacent teeth of adjacent discs being slightly uniformly angular- FRANK M. BCHAEFER.

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