US2205929A - Pencil attachment - Google Patents

Description

.Ime 25,1940. J. R. MUSGRAVE 2,205,929

rauen. A T CEMENT original F11 une s, 1955 Patented June 25, 1940 UNITED STATES PATENT OFFICE PENCIL ATTACHMENT James R. Musgrave, Shelbyville, Tenn.; The

Peoples National Bank, Shelbyville,. Tenn., and n The Third National Bank, Nashville, Tenn., ad-

ministrators of said James R. Musgrave, deceased, assignors to Musgrave Pencil Company, Inc.,'a corporation of Tennessee Continuation of applications Serial No. 24,735, June 43, 1935, and Serial No. 107,304, October 24,

1 Claim.

The invention relates particularly to a removable attachment for a lead pencil which carries a removable and replaceable eraser.

It `has been found that in many instances the lead pencil to which an eraser is permanently attached may be used up while' the eraser remains'good and at least partially unused. In other instances it is found that the eraser is used up before the pencil is entirely consumed. It is a purpose of the present invention to provide means by which a pencil may always be supplied with an eraser. It has been found convenientv to employ an eraser which is somewhat larger than the pencil with which it is associated and L the present invention is also directed to this end.

In general the invention comprises a slotted tube to receive a pencil at one yend, which tube is extended and enlarged at the other end to receive an eraser.

'Onespecic embodiment of the invention is illustrated in the accompanying drawing in which Figure 1 is a perspective view of a pencil attachment embodying the invention. Fig. 2 is a front elevation of the pencil attachment, a .pencil being illustrated in dotted lines in place in the attachment. Fig. 3. is a transverse vertical section of a pencil attachment on an enlarged scale. The drawing is not made to-exact scale and it is to be understood that the sizes, proportions and forms, both relative and absolute, of the various details may be varied and changed in other .embodiments of the invention.

The main portion of the attachment will be made preferably of metal. Preferably it will be very thin and the metal of which it is composed will be resilient and elastic to some extent. A tube I0, shown as cylindrical, may be formed to receive the .end of a pencil. The tube or the pencil may be round, hexagonal or of any suitable shape. Preferably the internal diameter of the tube portion I0 will be slightly less than the external diameter oi the pencil with which it is to be used. In order to conveniently accommodate pencils of slightly varying diameters and in order to assist in grasping the. pencil the tube I0 may be provided with a narrow longitudinal slot II which preferably will extend through nearly the entire length of the tube I Il. The slot I l may run to the lower or open end of the tube I0 and preferably terminate at nearly the inner end of the tube I0 in a somewhat enlarged circular opening I2. As illustrated in Fig. l the slot II may taper somewhat being slightly narrower at its open end. When the pencil is inserted and extends the tube` I0 the sides of the This application May 2, 1938, vSerial No.

(Cl. 1Z0-38) slot I I may become substantially parallel or diverge a little towards their open-end as illustrated in Fig. 2. It is toy be remembered that the entire structure is very small in actual di.k mensions and the tapering effect in Figs. 1. and-2 may be somewhat exaggerated, but is soshown to clearly illustrate the tendency.

At about the point where the cime rejoinsextending about the tube I0 from edge to edge of.

the slot II. The ribs I3 and I4 bulge outwardly so as not to diminish the innercircumference of the tube I0. The ribs I3 and I4 form reinforcemay ments for the thin, relatively fragile metal ofthe v tube I0. v'lhey add strength to the tubeA IIlLand tend to insure that when the pencil is thrust therein, and also while in use, the tube I0 doesy not crumple, buckle or otherwise undesirably deform. The inner corners or edges I5 of the ribs I3 and I4, and especially those which form the4 lower boundaries, that is those toward the open end of the tube I0, of the internal channels formed by the ribs I3 and I4 may be made sharply angular and clearly defined as indicated particularly in Fig. 3. Thus When the pencil is in position the tendency of the tube I0 will be to closely. and resiliently hug the pencil and any outward movement of the pencil will tend to cause the sharp edges I5 to be pressed upon the pencil and tend to bite into it and to the tend toA add to theresistance to removal of the pencil. Thus there may be procured a t and engagement of the tube I0 on the pencil, and without piercing,

approximating a rigid connection so that the `1itting may not be easily removed or displaced ticularly emphasized and there may be a tendency to split or break the thin metal of the tube I0 especially at this point. At the upper end of the tube I0 may bepro- Below the rib I3 and somewhat infromy 1.5-

lin

vided an inwardly projecting rib or ridge IG. This rib provides reinforcement of the metal and tends tc add to its strength against the expanding force of the pencil. The rib I6 extending inwardly also forms a stop against which the pencil may abut thus limiting the extent of the entrance of the pencil into the Vtube I0. This assures proper positioning of the device upon the end of the pencil without forming a shoulder or other shape on the pencil and without relying on engagement of the eraser with the end of the pencil for this purpose. The rib I6 thus limits the portion of the metal of the iitting which may be subject to the extra expanding force and also insures that the pencil may not be pushed against the overlying eraser which might tend to force the eraser from the fitting.

Integral with the tube I0 and the rib IB and extending upward therefrom and ilanging outward therefrom is a reinforcing and connecting band I'I. It will be seen that the outwardly expanding tendency of the pencil in the tube I0 will be resisted by the rib I6 and may also tend to distribute stress through the collar member I1. Since the collar member Il spreads outwardly some of the expanding stress caused by the pencil will tend to run longitudinally on the band I'I so that the tendency of the metal to resist the stress is not merely limited to the thickness of the metal but is resisted to some extent by the length of the metal in the band I'I. In this way some of the stress applied transversely to the metal of the tube I!) is shifted to longitudinal stress in the band I'I which thus very materially reinforces the tube I0. The annular tapered band I'I with its larger end disposed outwardly toward the eraser receiving and of the device also presents an abutment which is so directed that the ngers may be placed on the small end or tube I0 and against this abutment to get a good grip to remove the device from the pencil.

At the upper end of the anging collar II is provided a socket I8 for an eraser I 9. The eraser socket which may be of any suitable shape is here shown in tubular form and is preferably larger in diameter than the pencil holding tube II) and may thus hold and receive an eraser I9 which is larger than the pencil as is desired in modern practice. The eraser socket I8 is illustrated as provided with a plurality of ribs 20 which form an irregular interior surface against and past which the eraser I9 may be forced so as to be more or less rigidly held. Since the socket I8 is not nicked or pierced into the rubber it is evident that the eraser I9 may be removed and a new eraser replaced when desired. The form and shape of the eraser are not essential to the present invention. When desired a iiat eraser may be employed and the crown or exposed portion of the eraser may be larger than the socket I8 and may be of any suitable or desired form. The head portion of the eraser may be given distinctive shapes for utilitarian, ornamental or advertising purposes and the like. Pressure exerted when using the eraser may tend to bend the metal but the stress so Caused may be transferred in part at least to longitudinal compression of the band I'I.

The slot II permits the resilient tube I0 to spread as the end of the pencil is inserted in it and the other features provide the desired strength notwithstanding this slotting of the pencil receiving end.

For purposes of economy, pleasing appearance and usefulness it may be desired to make the attachment relatively small and its parts conveniently proportioned. It will be observed that the pencil tube portion I0 illustrated is less than half the length of the entire fitting and likewise the eraser seat portion I8 may be less than half the length of the entire fitting. It has been found that such an arrangement is economical and efficient and in a device made in accordance with the present invention offers sufficient gripping hold upon the pencil to insure the tting remaining and being held in place on the pencil.

The present application is a continuation of applications Ser. No. 24,735 iled June 3, 1935 and Ser. No. 107,304, filed October 24, 1936.

I claim as my invention:

A pencil attachment made of thin resilient metal comprising a tube adapted to receive a pencil of slightly larger diameter than theinternal diameter of the tube, a narrow longitudinal slot extending through the major portion of the length of the tube and tapering inwardly to the open end of the tube and provided at its inner end with an enlarged circular terminal close to the inner end of the tube, an outwardly projecting circumferential rib at about the junction of slot and circular terminal and extending to both edges` of the slot, a second outwardly projecting circumferential rib between the first rib and the open end of the tube and extending to both edges of the slot, sharp inner edges to the recesses un derlying both ribs extending eircumferentially about the inner surface of the tube, an inwardly extending circumferential rib above the circular terminal and at the inner end of the tube and forming a pencil stop and a reinforcement for the tube, an integral outwardly flaring band above the last mentioned rib and reinforcing the tube especially at its upper end, an eraser socket extending above the band and extending laterally of a line continued upwardly through the slot, and means in the eraser socket to engage and hold an eraser.

JAMES R. MUSGRAVE.

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