US592161A

US592161A - Mechanical lead-pencil

Info

Publication number: US592161A
Authority: US
Publication date: 1897-10-19
Anticipated expiration: 1914-10-19

Description

. a pencil containing my invention.

UNITED STATES- FREDERICK W. MUSSON, OF CHICAGO, ILLINOIS.

M ECHANICAL LEAD-PENCIL.

SPECIFICATION forming part of Letters Patent No. 592,161, dated. October 19, 1897.

, Application filed s in 6, 139 smart. 586,421. (ll'o nodelo To all whom it may concern.-

Be it known that I, FREDERICK W. MUSSON, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Pencils, of which the following is a specification.

My invention relates to lead-pencils, and particularly to lead-pencils in which the lead is movable-or adjustable, and'hasfor its object to provide simple and convenient means whereby the lead may be extended or withdrawn by the user as occasion may require.

I have illustrated my invention with some modifications and details, but I do not in so doing intend to be understood as saying that l have here illustrated all forms of my invention, for I am simply endeavoring by this means to set forth in an intelligible manner, so to speak, one form of my invention, and which form contains the principle. Of course this principle will be applicable in various ways to modified forms of the device.

Proceeding now to describe the particular forms and features which I have specially illustrated, I refer to the accompanying drawings, wherein w Figure 1 is a longitudinal section through Fig. 2 is a like section through a modification; Fig. 3, a like section through a further modification. Figs. 4, 5, 6, and 7 are details; Fig. 8, a section on the line 8 8 of Fig. 1. Fig. 9 is a section online 9 9 of Fig. 3. Fig. 10 is a detail of hexagonal lead and washer. Fig; 11 is a detail of square lead and washer. Fig. 12 is a side view of threaded lead, which in this case is round, or approximately so.

Like parts are indicated by the same letters in all the figures.

A is a body, preferably of wood, having a central aperture, and preferably provided with a head B. Within the aperture of this Wood body is the lead, which isvariously shaped-as, for example, it may be round, or oval, or hexagonal, or square, or any other shape, though, as will be hereinafter explained, the preferred form issomethin g other than round. C'indicates an oval lead; C, a found lead; C a hexagonal lead; C a square ead.

Associated with the forward end of the wood pencil proper is the pencil-tip D, having the outer portion, which terminates in a, small aperture through which the lead passes, and the inner portion D, which is preferably composed of spring metal and slotted so as to be capable of being forced into and then firmly held within the lower or outer end of the.

woodportion A. This tip also has the annular chamber E, which is preferably slottedv and made of spring metal and receives the nut F, internally screw-threaded at G and milled on its periphery at H. The annular chamber is cut away, as indicated in Fig 6, for example, so as to leave portions of the periphery of the nut F projecting, so that they can be pressed between the thumb and finger and thus the nut be turned within the annular chamber E. v

J and J are washers, which may be used, either one or both of them, in the end of the wood or body of the pencil preferably in proximity to the tip or point. They are used in conjunction with alead having a cross-section other than circular and when the aperture in the body A is not of such shape or size as to prevent the rotation of the lead. When,

howeveigthe aperture is of" the shape and size to prevent its rotation," the washers may be dispensed with. The" lead, whatever its shape, is preferably under most conditions smooth when applied.

A body portion with an oval aperture and a correspondingly-shaped lead is shown in Fig. 8, and a body portion with an aperture circular in cross-section in combination with an oval lead is shown in Fig. 9. In this case, of course, the oval lead must have associated with it one or more washers having oval apertures. In the case of the forms shown in Figs. 10 and 11 there must either be an ap erture in the body to correspond with the shape of the lead, so as to stop its rotation, or a washer which will accomplish that re- 'sult. In Fig. 2 I show diagrammatically, as it were, a clamp or spring device K, which is forced against the side of the lead and thus prevents it rotating, when neither the form of the aperture nor the washer would accom plish that result. The real essence of theinvention therefore consists in having a lead, an aperture in which it lies, the two related or shaped or provided with devices so that Ice the lead may reciprocate but will not rotate, and a thumb-controlled device for causing the lead to reciprocate.

As shown above, the means for holding the lead from rotating may either be an aperture of the shape of the lead or washers having holes the shape of the lead, or the lead may have a clamp like K or other such device to hold it from rotating. The preferred construction is an oval lead with an oval aperture and a threaded nut to engage the lead at the extremities of the long axis of its crosssection, so as to give clearance and permit the lead cut out by the teeth of the nut to free itself. The nut serves not only to feed the lead forward, but also to grip it and keep it from sliding longitudinally when such motion is not desired. This device therefore serves both to feed and to grip the lead.

I claim- 1. A lead-pencil comprising amovable lead of non-circular cross-section, the case for said lead having a longitudinal bore which is substantially of the same cross-section, to prevent rotation of the lead, said bore being enlarged at its lower end, a tip having a plain cylindrical portion fitted to the end of the case and a conical end,a nut mounted in the tip near the junction of the cylindrical and conical portions, said lower end and conical portion forming recesses to receive the cuttings or refuse of the lead, said nut being revolved to form notches in and move the lead, substantially as described.

2. A lead-pencil comprisinga movable lead of non-circular cross-section, a case for said lead having a longitudinal bore which is of substantially the same cross-section, to prevent rotation of the lead, said bore being enlarged at its lower end, a tip havingaslotted cylindrical spring portion D, fitted within the enlarged part of the bore at the end of the case, and a nut mounted in the tip and adapted to engage the lead, and when rotated, to reciprocate it.

FREDERICK W. MUSSON.

\Vitnesses:

BERTHA C. SIMS, L. W. J OHNSTONE.