US2170867A - Pencil - Google Patents

Description

K. MILLER Aug. 29, 1939.

PENCIL Filed May 18, 1959 a/ 4f w 4 NL Patented Aug. 29, 1939 PATENT OFFICE PENCIL Kay Miller, New Brunswick, N. J., assignor to Joseph Dixon Crucible Company, Jersey City, N J., a corporation of New Jersey Application May 18, 1939, Serial N0. 274,358

Claims.

The invention relates to an improvement inA pencils, and more particularly to an improvement in rellable, mechanical pencils especially adapted for use by draftsmen, artists and the like. In

5 the use of mechanical pencils of this character,

when the lead or other marking material has become worn or broken it is necessary to loosen the lead-holding devices and manually advance or pull out the lead a predetermined distance and then close down the lead-holding devices on the lead, as distinguished from the operation of reillable mechanical pencils especially designed for use by the general public inwhich, when it is desired to have a fresh supply of lead, it is only necessary to turn the body portion of the pencil or parts connected therewith in either clockwise or counter-clockwise direction to present a fresh length of lead for use.

There are on the market various forms of rei'illable, mechanical pencils designed especially for the use of draftsmen and artists as distinguished `from rellable mechanical pencils designed for use by the general public. A basic requirement of the mechanical pencils for use by draftsmen and artists is that the lead or other marking material be held firmly in place so that regardless of the pressure exerted upon the lead, it Will not recede into the hollow body portion of the pencil. In this type of pencil the lead or other marking material, which may be composed of graphite or a composition of colored ingredients, is held by contractible jaws. The central, longitudinal bore extending through the jaws and the body portion of the pencil is usually of a predetermined diameter and accommodates a stick or sticks of marking material of substantially one size. These contractible jaws as heretofore constructed have in the majority of commercial forms of reiillable, mechanical pencils adapted for drafting and artistic work, been connected at their inner end with the outer end of a hollow member integrally connected with an` element detachably secured to the body portion of the pencil or with an intermediary element mechanically connected therewith. To bring the jaws against the stick or shaft of marking material, a cap member is provided having an internally threaded inner end and an internally tapered outer end which is adapted to engage with the outer end, usually 50 tapered, of the lead-holding member. The dini;-

culty with this form of construction is that by reason or its fixed connection at its inner end with the body portion of the pencil, it has a relatively short period of effective gripping of the marking material. Moreover, if by chance the shaft or (Cl. 1Z0-21) stick of marking material should be pushed into the outer end of the chuck or lead-holding member, it is a matter of considerable diiii'culty to project the lead from the chuck, and various eX- pedients have been used to accomplish this act, as by providing the opposite end of the pencil with a removable cap, so that an instrument may be inserted therein to push the lead forward and eXtrude it from the chuck.

One object of the present invention is to produce a rellable, mechanical pencil especially 1 adapted for use by draftsmen and artists which will hold the leads or sticks of marking material more firmly than they are held in this type of relable mechanical pencils on the market today and which are so constructed and arranged that i when the lead is broken or worn down iiush with the outer end of the pencil the removal of the cap `gives access to a longitudinally-movable leadholding member so that an appropriate amount of lead may be drawn outwardly and then the leadholding member slid back to normal position after which the cap may be placed thereon to hold it rmly. Another object of the invention is to i produce a lead-holding means for rellable mechanical pencils which will be more durable in use than the lead-holding means with which rellable mechanical pencils are at present provided. To these ends the invention consists in the improved rellable mechanical pencil hereinafter fully described and particularly pointedout in the appended claims.

In the accompanying drawing illustrating the preferred form of the invention, Fig. 1 is a side elevation oi the lead-holding end of the improved pencil; Fig. 2 is a longitudinal section, in en-- larged view, through the pencil parts shown in Fig. 1 and indicating the position of the parts prior to bringing the lead-holding member into gripping engagement with the lead; Fig. 3 is a view similar to Fig. 2, but showing the position of the parts when the lead-holding member has p been brought into gripping engagement with the lead; Fig. 4 is a transverse section taken on the line 4--4 of Fig. 3; and Fig. 5 is a longitudinal section of the lead-holding member.

The body 8 of the improved reiillable mechanical pencil is an elongated member and may be composed of wood, metal or other suitable material and be either cylindrical or polygonal, and provided at one or both ends with means for holding a lead or other marking material composed of graphite or colored composition. To accommodate the lead 9 the pencil body 8 is provided with a longitudinal bore l0. These partsmay be of the usual construction and arrangement found in rellable mechanical pencils.

The improved devices of the present invention for removably holding the lead in xed position in one or both endsof the pencil body comprises a sleeve I2 having a longitudinal bore I3 and `threaded externally to screw into the enlarged outer end of the bore Il] of the pencil body 8 and having a projecting externally threaded outer end I4. A nut I5 which may be either cylindrical or polygonal, in the present instance, polygonal, to conform with the periphery of the pencil body 8, is threaded onto the lsleeve I2 to lock the sleeve I2 in the outer end of the pencil body by a tight engagement with the outer end of the pencil body. For this purpose the inner end of the nut I5 is provided with a tapered countersunk recess I1 which ts snugly over the corresponding tapered outer end I8 of the pencil body. It will be understood that whenthe internal taper I'l of the nut I5 iits over the external taper I8 and the nut is turned inwardly so as to bring the corresponding tapers into tight engagement, the sleeve I2 is iirmly locked in the outer end of the pencil body, with the externally threaded end I4 of the sleeve I2 projecting outwardly therefrom.

' The pencil-holding member is collet-like in form and consists of a cylindrical element 2U provided with a longitudinal bore 2I which may beof any preferred diameter to accommodate sticks of graphite or other black or colored marking material of various diameters. The inner end 22 of the lead-holding member has a smooth cylindrical periphery which is adapted to have a sliding t in the outer cylindrical bore 24 of the sleeve I2 so as to be readily removable therefrom. The outer end of the lead-holding member is slotted longitudinally, at a plurality of points, in the present example three, as indicated lby the reference numeral 25, so that the outer end of the member 20 will be collapsible upon the lead inserted therein.

The means for collapsing the outer end of the member 2D' to bring it into gripping engagement with a lead is a` cap 26 the inner knurled end 21 of which is internally threaded to screw over the external thread of the outer end of the sleeve I2. The outer end oi the cap 26 is provided with an internal taper 28 which is adapted to close down upon the external taper 29 formed on the periphery of the outer enlarged end 30 of the lead-holding member 2|.

Assuming that the operating parts of the lead-holding elements` of the improved pencil are in the condition shown in Fig. 2 and that a lead of substantially the same diameter as the internal diameter 2I of the lead-holding member 20 has been slid longitudinally into the pencil, the cap 26 is turned inwardly until the internal taper 28 of the cap 26 ts snugly against the externally tapered outer end 29 of the member 20, which is known by the fact that it is impossible to turn the cap 26 further, the collapsible outer end of the member 20, made so Y by the longitudinal slots 25, is brought into firm gripping engagement with the lead, a grip so i'lrm that it is impossible in any ordinary use of the pencil to push the lead inwardly into the body of the pencil. When it is desired to extend the protruding end of the lead it is simply ynecessary to unscrew the cap 26 slightly and pull outwardly on the lead the desired distance and then again screw inwardly on the cap 26. If by chance the lead should become broken flush with the outer end of the cap 26, the lead may be readily pulled out by completely unscrewing and removing the cap- 26 and then by the ngers collapsing the outer end of the member 20 onto the lead and pulling outwardly thereon, so as to remove it from the sleeve I2. The member 20 is then moved inwardly relatively to the lead and again inserted into the sleeve I2, after which the cap 26 is screwed inwardly onto the outer end of the sleeve. In like manner when the lead has been used down to the minimum of usable length, the stub may be easily pushed out of the lead-holding member 20 and a fresh length of lead inserted therein.

From the foregoing description it will be understood that the improved reiillable mechanical pencil of the present inventionprovides a simple, strong and durable means for so` iirmly gripping the lead that it cannot move or be pushed inwardly into the pencil body by pressure exerted upon it during use, and that if the projecting end of the lead should become broken flush with the end of the holding means, a fresh length of lead may be pulled outwardly from the pencil body by irst unscrewing the cap, then pulling out the lead-holding member from the sleeve, then holding the lead and reinserting the lead-holding member into the sleeve, after which the cap may be screwed inwardly into place.

Having thus described the invention, what I claim as new is:

l. A pencil of the character described coman internally tapered outer end adapted to t over the tapered portion of the lead-holding member and an internally-threaded inner end adapted to be screwed onto the outer end of the sleeve, the opening in the outer end of the cap being of a diameter slightly greater than the diameter of the outer end of the lead holding member for spacing the outer end of the cap from the lead.

2. A pencil of the character described comprising a body having a longitudinal bore therein,

a sleeve fixed in one end of the pencil body and having a projecting outer end, a lead-holding member slidingly received in the projecting end of the sleeve and having a collapsible outer end, and a cap having an opening at its outer end for collapsing the outer end of the lead-holding member onto a lead, the opening in the outer end of the cap being of a diameter slightly greater f than the diameter of the outer end of the lead holding member for spacing the outer end of the cap from the lead.

3. A pencil of the character described comprising an elongated body having a longitudinal bore therein, a sleeve secured in one end of the bore and having a projecting, externally threaded outer end, a lead-holding member the inner end of which is slidingly received in the outer end of the sleeve and the outer end of which is longitudinally slotted so as to be collapsible upon a lead, and a cap having an opening at its outer end mounted on the outer end of the sleeve for collapsing the outer end of the lead-holding member to bring it into gripping engagement With the lead, the opening in the outer end of the cap being of a diameter slightly greater than the diameter of the outer end of the lead holding member for spacing the outer end of the cap from the lead.

4. A reflllable pencil comprising a body having a longitudinal bore for accommodating a lead, an externally-threaded sleeve threaded into one end of the body, a nut carried by the sleeve for locking the sleeve in the body, a lead gripping device having a central longitudinal bore for receiving the lead, the periphery of the inner end of the lead gripping device being arranged to have a snug sliding t in the outer end of the sleeve, the outer end of the lead gripping device being slotted and the periphery thereof being tapered, and a cap having an opening at its outer end and tapered internally at its outer end to rit over the tapered outer end of the lead gripping device and having an internal thread at its inner end. to screw onto the outer end of the sleeve so as to collapse the outer end of the lead gripping device to close it upon the lead, the opening in the outer end of the cap being of a diameter slightly greater than the diameter of the outer end of the lead holding member for spacing the outer end of the cap from the lead.

5, A pencil of the character described comprising an elongated body having a longitudinal bore therein, a sleeve secured in one end of the bore and having a threaded portion projecting therefrom, a lead-holding member having a central bore for receiving a lead slidingly mounted in the outer end of the sleeve, the outer end of the member being slotted longitudinally and having a tapered periphery, and a cap having an opening at its outer end and the inner end f which is threaded internally for engagement With the outer end of the threaded portion of the sleeve and the inner surface of the outer end of which is tapered to fit over the tapered end of the leadholding member to collapse it into gripping engagement With the lead, the opening in the outer end of the cap being of a diameter slightly greater than the diameter of the outer end of the lead holding member for spacing the outer end of the cap from the lead.

KAY MILLER.

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