US3183894A - Pencil sharpeners - Google Patents

Description

May 18, 1965 H; HAMPTON 351835894 BENCIU: SHRPENER'IS" Filed? Aug., 14;, 196s..

'9/ s Mg ATTORNEY United States Patent Pce 3,183,394 FENCE.. SHARPENERS Hugh H. Hampton, 2903 17th St., Sacramento 18, Calif. Filed Aug. 14, 1963, Ser. No. 302,168 Claims. (Cl. 1Z0-92) This invention relates to pencil Sharpeners and more particularly to such Sharpeners for the lead point of mechanically operated lead pencils.

The invention of this `application has relation to and is a variant of the pencil Sharpener set forth in my United States Letters Patent No. 3,049,096 dated August 14, 1962.

The devices known as mechanical pencils are well known and may be broadly described as having a metal or plastic case containing a stick of lead which may be advanced and retracted for use. i

A main problem present in sharpening the lead of such mechanical pencils is the protection of the pencil case from contact with the cutter blades of the `sharpener, and the proper aligning of the lead point of the pencil with the cutter blade of the sharpening device, since such lead is usually relatively thin inl diameter and is quite susceptible to breakage if placed under substantial pressure laterally in order to align the 'lead point with the sharpening blade. Another problem to be met is the provision of a suitable carrier for such a cutter blade.

In the present invention the purpose and principal object is to provide a Sharpener for the lead point of pencils, and particularly mechanical pencils, in which a resilient cutter-blade support or carrier is loosely mounted in a tubular housing for self-alignment of the cutter blade member with the lead of the pencil, and to provide a resilient portion incorporated into thebody of such housing per se whereby the blade-carrier may be operated from the exterior of 'the housing by manual pressure on the housing on a flat surface ofthe blade carrier, without interposition of other mechanical means. Y

Further objects are to provide in such a Sharpener a means to vstabilize the cutter-blade carrier against excessive axial rotatio-n; to provide a housing for such a Sharpener which may be integrally molded; to provide in such a housing protecting and guiding means for the tapered portion of the casing at the point of a mechanical pencil; and to provide a simple, etlicient and economical Sharpener for lead points of mechanical, and other pencils.

Preferred forms in which the invention may be exempliiied are more fully described in the following specification and illustrated in the :accompanying drawing, in

which: j i

FIG. 1 is a longitudinal transverse central section of one form of the invention, on line 1-1 of FIG. 2,'but

f without section of the cutter blade carrier member.

FIG. 2 Vis a lateral transverse central section on line 2-2 of FIG. 1.

FIG. 3 is a `longitudinal transverse central section of a modified form of the invention.

FIG. 4 is a longitudinal transverse central section of another modified form of the invention.

FIG. 5 is a longitudinal transverse central section of another modified form of the invention.

FIG. 6 is a lateral transverse section on line 6-v6 of FIG. 5. Y

FIG. 7 is a fragmentary lateral section on line 7-7-of FIG. 5. j g' FIG. 8 is a reduced side elevation of FIG. 5.

Referring to the drawings in which like reference characters indicate corresponding parts in the several views of the respective modifications, and referring rstly to the exempliication of FIGS. l .and 2, an integral elongated tubular housing 10 of suitable length is provided preferably of a moldable plasticized material such as yeldable m8338914 Patented May is, rees vulcanized rubber, or suitably treated polyvinyl synthetic plastic, both of which materials are well known. It is preferred that the tubular housing member 10 be externally generally cylindrical, more particularly at its opposite end portions 11, 12. The housing may be of resistently yeldable resiliently exible material throughout its length, but more especial-ly at its longitudinal central portion where it is provided with a resiliently flexible wall portion which is shown in FIG. l as a longitudinally elongated depression 13 formed by decreasing the thickness of the resilient material in the area of the depression and thereby making the wall more flexible and resilient. This depression 13 is preferably at the exterior surface of the housing rather than at the interior thereof.

vAt its interior, one end portion of the tubular housing provides a cylindrical chamber 14 for a suicient portion of its length to rotatably mount therein a tip guide member 15 and a iixed annular retaining collar 16 which holds the tip guide rotatably in the cylindrical chamber. The tip guide 15 seats against a shoulder 19 and has an axial inverted truncated conical bore 17 therethrough for receiving rotatively the tapered end of a lead pencil or the tapered easing of a mechanical pencil, the vertex opening ofthe conical bore being inwardly. The remainder of the internal length of the housing is a blade-carrier chamber 13 which is preferably oblong-rectangular in lateral section adjacent its opposite ends 18 and cylindrical centrally at it". The housing may be open at its opposite or lower end 2u, and have a transverse pin 21 across said open end to loosely `support a cutter-blade carrier member generally indicated 22. To facilitate molding a plastic body the lower rectangular tube portion 18 may be a separately formed insert block 24.

The cutter-blade carrier 22 comprises .an integral retroverted leaf-spring strip Apreferably defining an elongated generally U-shaped member of resilient leaf-spring material, the closed end 23 of the U resting loosely on the pin 21 and the two spring-arms 22a and 22b of the U- shaped member extending generally parallel toward and terminating in closely spaced proximity to the shoulder 19, and thereby being manifestly in close proximity to the truncated vertex of the inverted conical bore 17 of the tip guide. The spring arms 22, 22h have relatively wide elongated planar faces preferably of a width having loose slid-able clearance in the oblong rectangular chambers 18 .at the opposite ends of the housing. The free terminal end portions of said arms adjacent to the tip guide are inclined outwardly as at 25, and at least one of the inclined portions' 25 mounts a cutter blade 26. Preferably there is a cutter blade at the end portion of each of said arms, though a single blade is efficiently operative.

The opposed spring-arms 22a, 22b are tensioned outwardly, that is, away from each other, so that the free ends at the cutter blades are normally spaced apart adjacent to the tip guide.

Intermediate the ends, and preferably substantially at the longitudinal central portion of the spring arms, in opposed relation to the resilient housing area 13, each of said arms is oppositely deformed arcuately outwardly from .alignment for a short portion of its length (such asi approximately one-fourth), providing a pressure area 27 in each arm which may have superficial contact with the opposite resilient pressure areas 13 of the housing, and provides a central pivot point on which the cutter blade carrier may rock so that its loose opposite ends may oscillate.

As shown in FIG. l, the open end 20 of the tubular housing may be closed by an end-closure cap 28 which may be removably mounted by means of cooperating threads 29 on the housing and within the wall of the cap. Such a closure for the open end of the casing may aisasst likewise be employed in all the modified forms of the invention shown in other iigures.

In operation of the device exemplied in FIGS. l and 2, the tapered point portion A of a pencil, or the casing of a mechanical pencil, is inserted in the in verted conical bore )i7 and the lead point of the pencil extending through the truncated vertex opening of the bore as shown in FIG. l., which places the lead point between the cutter blade members 26, the incline thereof being at a proper angle to sharpen a pencil point. The spring arms of the cutter blade which are spring-biased outwardlykrnay be pressed inwardly toward each other by manual finger pressure on the resiliently flexible portion i3 ofV the housing, bringing the cutting blade or blades into cutting relation with the lead point of the pencil. lf, in manually pressing the spring-arms 22 and the cutter blad-es 26 inwardly toward each other, the axis thereof would not normally be perfectly aligned with thev lead point of the pencil, said blades may still engage the lead of the pencil point, and due to the loose mounting of the blade carrier member it may pivotally oscillate on the fulcrum or pivot point provided by the portions 27 against the inwardly pressed portions 13 of the side wall of the casing, and thus negative or at least minimize lateral pressure of the cutter blades 26 against the lead of the pencil and thereby eliminate or greatly minimize a probability of breakage of the pencil point during the sharpening operation.

The mounting or" the opposite ends of the blade carrier in the rectangular portionslS serve to restrict excessive axial rotation Vof the blade carrier for purpose of maintaining broad flat faces of the spring arms subject to pressure by the inwardly pressed portion of the housing.

Manifestly, if'the lower end 2i) of the housing is open, the lead havings or any broken pieces of lead are cleared from the housing, but it is preferred to contain such shavings and pieces of lead by means of the removable cap 29 lwhich may be ,intermittently removed `for cleaning.

In FIG. 3 thereA is a modification from FIG. l in the housing and in the cutter-blade carrier. The elongated tubular housing Ilia is cylindrical internally and externally, having at one end a cylindrical chamber portion Ma including therein a rotatable tip-guide 15a, and an annular retaining ring 16a at the outer end of the tip guide, as well as'shoulder 19a at the inner end of said chamber and tip-guide. The remainder of the housing comprises a tubular chamber portion lSa which may be cylindrical except for blister members to be described. At the lower end of the tubular housing is a cross-pin 21a. An inverted conical tip-guide bore is indicated 17a.

In this modiiication the housing may be of similar material-as in FlG. 1, and the longitudinally central portion 13a is flexibly resilient, and has oppositely disposed internal blister enlargements 27a which extend inwardly and have facial contact bearing against the broad face surfaces at the longitudinally central portion of each of the arm springs 22a and 2Zb of the cutter-blade carrier 22. In this modication each of the spring-arms may be in straight alignment and they are spring-biased oppositely outwardly away from each other, the same as in FIG. 1, whereby cutter blades 26a are normally spaced apart adjacent to the tip guide. The closed end of the U-shaped cutter-blade carrier is loosely mounted on the cross-pin 21a at the lower end of the tubular housing. The pressure of the blisters 27a against the broad flat faces of the spring arms 22a, 22b restricts excessive axial rotation of the blade carrier.

Upon laterally pressing inwardly upon the flexible resilient portion 13a of the housing the cutter blade portion or portions 26a of the spring-arms are brought into engaging relation with the lead point of a pencil, as in FIG. l, and the loosely mounted spring-arms may pivot centrally of their length on the blister enlargements 27a forV laterally oscillating the opposite ends of the cutter-blade carrier to axially align, the cutter blade or blades with the engaged point of the lead of a pencil, without substantial lateral pressure against the lead point.

In the modiiication of FIG. 4 the cylindrical tubular yieldably resilient housing is indicated 1Gb. While a rotatable tip guide is preferred as in FIGS. l and 3, there is disclosed in the modification a tip guide portion 15b which is integrally formed at one end of the housing with a truncated inverted conical bore 17b having a fixed metal liner. Between the inner end of the tip-guide portion and the opposite or lower end of the housing, there is a cylindrical tubular portion 181: within the housing. The retroverted U-shaped cutter blade carrier 22 is mounted in the tubular portion 1812, and has straightly aligned spring-arms 22a and 2lb, the closed end of the U 23b being loosely mounted kon cross-pin 2lb at the opposite or lower end portion of the tubular housing, the springarms extending from such loose mounting to the opposite end portion of the cylindrical tube, and terminating in outwardly inclined free end portions 2511 in adjacent proximity to the inner vertex end of the inverted conical tip guide, said free ends ofthe spacing arms being springbiased relatively oppositely outwardly away from each other, and mounting inclined cutter blades 26h. Since the wall of the housing is yieldably resilient it may be manually engaged between the lingers of an operator in the zone of the longitudinal central part of the rectangular tubular portion lib, and pressed inwardly, thus bringing the cutter blade portions 26h into cutting relation with the lead point of a pencil. Since the blade carrier 22 is loosely mounted in pin 2lb and is engaged longitudinally centrally by the inward llexing of the housing wall, it is therefore adapted to pivot on itscentral portion which has pivotal engagement with the portion of the housing wall which is pressed inwardly by the iinger-tips of the operator, and may therefore oscillate for alignment with the lead point of a pencil in the tip guide, as heretofore described. Y y

In this modification, the means for preventing excessive rotation of the cutter blade carrier comprises slots 2711 in the spring arms and transverse pins 2S!) passing through said slots and anchored in the wall of the housing.

In the modification of FGS. 5 to 8 there is disclosed Y a simplified form of structure in which the parts may require a minimum of moulding. An elongated resilient deformable housing ltlc is provided which may be oi' uniform reislient consistency throughout its length such as well known resiliently yieldable standard and conventional cylindrical rubber tubing deformable by manual pressure, and shape-resuming when pressure is released. rlfhe housing lila may be cylindrical both internally and externally, and provide therein a cylindrical chamber 18C.

Externally circumferentially of this resilient tubular housing 10c is an elongated snugly itting rigid sleeve 30 which registers evenly with the upper end 11e of the resilient housing, the opposite end of said rigid sleeve extending beyond the opposite end 12C of said resilient housing.

Within the normally upper end llc of the resilient tubular housing is a pencil tip guide 15C. While, as previously stated, it is preferred that the tip guide be rotatable, in this modied form the ltip guide may be nonrotatable and comprise a separate preferably rigid plastic cylindrical plug bodyY tightly iitting within said open end of the tubular housing member. As in other modications there is an inverted truncated conical axial bore 17C through the tip guide, the Vlarger end of the bore being outwardly and its vertex inwardly. At its inner end within the tubular housing the tip guide 15C may mount a pair of extended tongues 18d which are relatively parallelly spaced and thereby provide therebetween a space 18e which is rectangularly oblong in lateral trans-axis section and provides a rectangular guide for the adjacent end of cutter-blade carrier 22.

At its normally lower end opposite the tip guide the resilient cylindrical housing stops short of the length of the outer rigid sleeve as indicated at 12C, and the remainder of the length of the rigid sleeve houses a tightly itted preferably hard plastic plug 24C which has an open socket 24d therethrough rectangular in lateral trans-axis section, providing a guide for receiving the lower closed end portion 23C of the U-shaped blade carrier 22, said closed end portion 23C being loosely mounted upon a giss-pin 21C adjacent to the end of the rectangular socket If desired, said lower end of the outer sleeve 30 may l2); provided with a threadedly mounted end closure cap Extending from its closed U-shaped end 23C which rests loosely on the cross-pin 21C, the blade carrier 22 has elongated substantially parallelly spaced spring-arms 22a and 22b, the free terminal ends of which extend substantially to, and are closely spaced from the inner vertex end of the inverted conical bore of the tip guide, and at said ends mount at least one cutting blade member 26C, said arms being spring-biased outwardly and normally away from each other, so that the said end of the arms bearing the cutter blade or blades are normally spaced apart. The opposite ends of the spring arms of this blade carrier 22 are disposed in the respective rectangular sockets 18e and 24d and the spring arms are guided therebyl against excessive axial rotation.

It is to be noted that the rigid sleeve 30 has oppositely positioned axially elongated fenestrations 31 substantially centrally of its length, and that the wall of the resilient tube housing c underlies the area of these fenestrations, whereby an operator may manually exert finger pressure through the fenestrations upon the resilient wall of the housing and thereby upon the spring arms 22a, Z2b of the cutter blade carrier, whichvis thus engaged on a pivot point centrally of its length whereby its loose opposite ends may oscillate to loosely align the cutter blade with the lead of the pencil point and thus avoid lateral pressure on the frangible lead point.

ln operation of all forms of the invention the tapered point of the pencil casing is inserted in the bore of the tip guide portion which places the extended point of the stick of lead beyond the inverted conical truncated vertex of the tip guide and into proper position between the spaced cutter blades for contact by the cutter blade or blades when such plates are manually moved inwardly from their normal spring biased outwardly spaced position, whereupon the axial rotation of the pencil and the lead sharpens the lead. If the pencil be of the mechanical type having a tapered metal casing at the pencil point, the tip guide will prevent injury to the Itapered casing. Manifestly, the preferred rotatable tip guide facilitates such rotation of the pencil casing, but the non-rotatable tip guide of the FIGS. 4 and 5 are more simpliiied and cheaper in manufacture and operate in an acceptably satisfactory manner.

It is to be noted that in all forms of the invention there is a loosely mounted U-shaped resilient cutter-blade carrier 22, which has generally parallel elongated spring arms providing relatively wide at faces which are stabilized in the housing against excessive axial rotation, the free ends of the arms terminating adjacent to the vertex of the contical tip guide, and the cutter blades being tensioned outwardly or away from each other and away from the normal position of the pencil lead to be sharpened; and that there is a resilient portion incorporated at the longitudinally central portion of the side-Wall of the tubular housing providing in the body of the housing per se a manually operable means to bring the cutter blades into cutting relation with the lead point of `a pencil inserted through the tip guide. It may be further noted in all forms of the invention that engagement of said resilient portion of the housing is against the flat wide faces of the arms longitudinally centrally of the arms of the loosely mounted cutter blade carrier, whereby the cutter blade carrier and its arms may oscillate pivotally on such longitudinal central engagement for aligning the cutter blade or blades with the lead point of the pencil, which in relation to the structure of the device is in alignment with the axis of the inverted conical bore of the tip guide.

While the lateral respective widths of the broad faces of the blade carrier are subject to some alteration and choice which would be apparent to those skilled in the art, such Width of the blade carrier may be exemplied as two to three sixteenths of an inch.

Having described the invention, I claim:

l. A Sharpener for the lead point of a pencil, comprising an elongated tubular housing having at one end portion a pencil tip guide provided with a truncated inverted conical bore, the vertex of the bore being inward, an elongated cutter-blade carrier in the tubular housing comprising a pair of relatively spaced generally parallel elongated resilient spring arms integrally connected relatively at one end which is loosely mounted in one end portion of the housing opposite the tip guide, said spring arms extending from said loosely mounted end toward the tip guide and having the free ends thereof terminating in adjacently spaced relation to said tip guide, the free ends of said arms being spring biased outwardly oppositely away from each other whereby said free ends are normally spaced apart, cutting blade means at said free end portion of lthe arms, said housing having a resiliently exible area centrally of its length and manually depressable inwardly against said spring arms for bringing the free terminal ends of the ams toward each other and the cutter blade means into cutting relation adjacently spaced from the adjacent end of the inverted conical bore of the tip guide, the longitudinally central portion of the spring i arms being adapted for pivotal bearing against said longitudinal central inwardly pressed portions of the housing for oscillating pivotal movement thereagainst, whereby the cutter blade portion at the free end of the spring arms may be aligned with the axis of the tip guide.

2. A pencil sharpening device as set forth in claim l and in which said tubular housing includes means to retrict axial rotation of the cutter blade carrier.

3. A Sharpener for the lead point of a pencil as set forth in claim l and in which the said tubular housing is encased in a tubular rigid sleeve having at its longitudinally central portion a fenestrated opening, the flexible resilient portion of the housing underlying said fenestrated opening whereby said exible resilient portion of the housing may be manually depressed against the spring arms.

4. Means to sharpen thelead point of a pencil, comprising an elongated tubular housing including therein a tubular chamber, a pencil tip guide at one end portion of the chamber provided with a truncated inverted conical bore, a cutter blade carrier mounted in the said chamber and comprising a pair of relatively spaced generally parallel elongated spring arms integrally connected relatively at one end which is loosely mounted in one end of the tubular chamber, said spring arms extending from said loosely mounted end toward said tip guide and having free ends thereof terminating in adjacently spaced relation to the vertex end of the bore of the tip guide, said arms being spring-biased outwardly oppositely away from each other whereby said free ends are normally spaced apart, cutting blade means at said free end portion of the arms, said housing being resiliently iexible centrally of its length and manually depressable inwardly against said spring arms for bringing the free terminal ends of the arms and the cutter blade means toward each other and into cutting relation adjacently spaced from the adjacent end of the inverted conical bore of the tip guide, the said spring arms having a broad face and the resilient flexible central portion of the housing wall being manually depressable inwardly against said broad face of the spring arms, whereby the cutter blade portion at the free end 3,183,894 Se of the spring arms may be aligned with the axis of the References Cited by the Examiner.

tip guide. UNITED STATES PATENTS 5. A pencil sharpening device as set forth in claim 4, 969 323 9/10 f Anderson 120 93 and including means in the tubular member for stabilizing l 263738 4/18 Boyle 120 85 the cutter blade carrier against axial rotation in excess {531;738 3/25 Davis no gS of forty-five degrees from a normal position wherein the 049,096 8/62 Hampton i 120 95 broad faces of the spring arms are in face-to-face opposed relation t0 the resilient portion of the housing which is pressable inwardly thereagainst.

JEROME SCHNALL, Primary Examiner.

LAWRENCE CHARLES, Examiner.

n i fifi.

Claims (1)

1. A SHARPENER FOR THE LEAD POINT OF A PENCIL, COMPRISING AN ELONGATED TUBULAR HOUSING HAVING AT ONE END PORTION A PENCIL TIP GUIDE PROVIDED WITH A TRUNCATED INVERTED CONICAL BORE, THE VERTEX OF THE BORE BEING INWARD, AN ELONGATED CUTTER-BLADE CARRIER IN THE TUBULAR HOUSING COMPRISING A PAIR OF RELATIVELY SPACED GENERALLY PARALLEL ELONGATED RESILIENT SPRING ARMS INTEGRALLY CONNECTED RELATIVELY AT ONE END WHICH IS LOOSELY MOUNTED IN ONE END PORTION OF THE HOUSING OPPOSITE THE TIP GUIDE, SAID SPRING ARMS EXTENDING FROM SAID LOOSELY MOUNTED END TOWARD THE TIP GUIDE AND HAVING THE FREE ENDS THEREOF TERMINATING IN ADJACENTLY SPACED RELATION TO SAID TIP GUIDE, THE FREE ENDS OF SAID ARMS BEING SPRING BIASED OUTWARDLY OPPOSITELY AWAY FROM EACH OTHER WHEREBY SAID FREE ENDS ARE NORMALLY SPACED APART, CUTTING BLADE MEANS AT SAID FREE END PORTION OF THE ARMS, SAID HOUSING HAVING A RESILIENTLY FLEXIBLE AREA CENTRALLY OF ITS LENGTH AND MANUALLY DEPRESSABLE INWARDLY AGAINST SAID SPRING ARMS FOR BRINGING THE FREE TERMINAL ENDS OF THE AMS TOWARD EACH OTHER AND THE CUTTER BLADE MEANS INTO CUTTING RELATION ADJACENTLY SPACED FROM THE ADJACENT END OF THE INVERTED CONICAL BORE OF THE TIP GUIDE, THE LONGITUDINALLY CENTRAL PORTION OF THE SPRING ARMS BEING ADAPTED FOR PIVOTAL BEARING AGAINST SAID LONGITUDINAL CENTRAL INWARDLY PRESSED PORTIONS OF THE HOUSING FOR OSCILLATING PIVOTAL MOVEMENT THEREAGAINST, WHEREBY THE CUTTER BLADE PORTION AT THE FREE END OF THE SPRING ARMS MAY BE ALIGNED WITH THE AXIS OF THE TIP GUIDE.

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