US2221239A - Apparatus for pointing elongated material - Google Patents

Description

5. H. JOHNSTON APPARATUS FOR POINTIIiG ELONGATED MATERIAL Nov. 12, 1940.

Filed March 11, 1940 Jtafford H. J ofmston Patented Nov. 12, 1940 uui'reo STATES 2,221,239 APPARATUS FOR ronv'rmo ELONGATED Stafford 11. Johnston, Washington, D. 0.

Application March 11,

Claims.

This invention relates to the shaping of elongated material, such as lead for pencils, and more particularly to apparatus for pointing elongated material.

In illustration work and the preparation of drawings for architectural, engineering and other activities, draftsmen ordinarily are constantly required to obtain a sharp axial point on their drafting implements, such as pencils, crayons or charcoal.

Heretofore, recourse has been had to pointerpads consisting of strips of sand papers glued to a hand board. Such pads are used by holding the pad on the table with one hand and stroking the sand paper with the lead end held in the other.

After practice, a fairly satisfactory point is obtained with pointer pads but usually the removed graphite dust blows over the desk to soil the work, as well as the draftsmans hands and attire.

In an effort to prevent soiling by graphite dust, it has been proposed to construct apointe'r including a box having a floating cutter at one end with resiliently mounted blades. If the structure could be made to work it would prevent loosely scattering the graphite dust; but ,the resilient blade mounting is complicated, hard to keep in working order and expensive to manufacture, besides rendering it diificult to obtain the proper cutting pressure on the lead due to the yielding 80 blade housing.

Accordingly, it is an object of the present invention to provide pointing mechanisms which will be simple in construction, economical to manufacture and efficient in operation.

Another object of the invention is to provide a simple pointing mechanism so formed as to lie fiat without rolling from any predetermined position.

In one form of the invention, a container has a closure cap rigidly 'holding three integral radially disposed blades. The blades have angula'rly disposed cutting edges which are contiguous at the axis of the container to point a pencil lead advanced through a recess in the cap.

In another form the fixed blades are not integral but are fixed to three integral support elements in the cap. In another form, angular support elements for the fixed blades are assembled by soldering, welding or other attaching means.

A further modification involves making the container with fiat sides to prevent rolling.

The invention will be understood by the following detailed description, read in conjunction with the accompanying drawing, forming a part there- 55 of, wherein 1940, Serial No. 323,429

Fig. 1 is a top plan view of a preferred form of the invention;

Fig. 2 is a section on the line 2-2 of Fig. ,1;

Fig. 3 is an elevation showing the preferred form of cutter;

Fig. 4 is a bottom plan view of the cutter of Fig. 3;

Fig. 5 is an elevational view of a modified blade; 1

Fig. 6 is an elevation of a modified cutter;

Fig. 7 is a bottom plan view of the cutter of Fi 6;

Fig. 8 is an elevational view of a second modified form of cutter;

Fig. 9 is a bottom plan view of the cutter of 15 Fig. 8; l

Fig. 10 is a top plan view of a modified pointer assembly;

Fig. 11 is a top plan view of a further modified pointer assembly; and

. Fig. 12 is an elevation of the construction of Fig. 11, with a fragmentary section showing the primary form of cutter therein.

Referring particularly to the preferred form of the invention, illustrated in Figs. 1 to inclusive,- a lead pointer includes a hexagonal cap l6 having a top 11 and flat sides l8 forming projecting comers IQ for preventing rolling.' The cap has an axial hole 20 for admitting leads, crayons, sticks or spindles to be pointed and is characterized by an internal groove 2| for close attachment as a closure element for circular container 22. Neck 23 of the container has a spiral head 24 which engages with groove 2| for tightening cap 16 in efiective closing relation on container 22, I

Internally, cap I6 is provided with circular recess 26 for snugly accommodating circular cutter 21. Cutter 21 in its simplest aspect is integral in design, consisting of disc 28 of good quality steel for temper, such as 22-gauge tool steel. Disc 28 has axial hole 29 and a peripheral rim 30 supporting lead-scraping blades 3|, 3la and 3"; radially disposed with respect to the axis of the cap IE or container 22. Referring particularly to Figs. 3 and 4 it will be observed that blades 3|, 3la and 3lb are struck up from the material of disc 28, being bent along lines 32 and each provided with a curved rear'edge 33 conveniently to clear container neck 23 in assemblage. Each blade has an inclined front face 3t characterized by a radially aligned cutting edge 35 which at its extremity is contiguous to the cutting edges of the other blades and accurately disposed in the axis of hole 20. Preferably, axial hole 20 is countersunk to facilitate invention.

A conventional drafting pencil 36 has a projecting lead 31 which constantly requires a fine point 38. Referring particularly to Fig. 2, when lead 31 is inserted in hole 20 and coaxial hole 29 and rotated during advance with just sufiicient pressure to scrape off the graphite, continuance of its advance and rotation soon results in pointing the lead as it advances along blade 3|, 3| a and 3|b until the lead attains the point where the fixed blades are contiguous.

Pointing of the pencil as indicated produces graphite dust which falls into the container 22 as debris. It will be understood that the volume of container 22 may be of any desired value; ordinarily a two-ounce glass bottle will sufiice to hold the graphite dust accumulated from pointing operations over several days. When the container is transparent as in Fig. 2, convenient visual inspection is afforded in order to observe the progress of the sharpening operation. However, the container may be of material other than transparent substances, in which case satisfactory inspection is afforded by simply withdrawing the point to observe the progress of the pointing operation. The container may conveniently be emptied by unscrewing cap l6 and dumping the debris,after which the pointer is reassembled by replacing the cap on the container. During this latter operation, the cutter is automatically aligned axially with respect to the cap or container, due to its nested relation in recess 26 of the cap.

It will be understood that the cutter may be of other material than 22-gauge steel to suit desired requirements and the cap and container may be of Bakelite or other thermoplastic, metal, or any conventional like or unlike material. Also, it will be understood that the cap as well as the container may be variously colored, ornamented or inscribed, as with identifying or advertising indicia.

In lieu of the integral construction of Figs. 3 and 4, there may be used as a feature of the cutter assembly the separable blade of Fig. 5 characterized by a straight base 4|, a curved rear edge 42 and inclined front face 43, the latter adapted for angular disposition with respect to the axis of the cap. This blade has elongated slot 44, parallel to straight base 4| for mounting on cutter disc 45 at axial hole 46, the latter for accommodating the lead to be pointed. The cutter assembly of Fig. 6 may be utilized in the same manner as the cutter of Figs. 3 and 4, normally being fixed between cap and container. Adjustability of the blades is a feature of the alternative form shown in Figs. 6 and 7, such blades therein being carried on support ears 4! integral with disc 45 and struck up at an angle therefrom. Each support car 41 has an aperture 48 for accommodating screw 49 extending through blade slot 44 and nut 50 to be tightened thereon to fix the blades rigidly with respect. to disc 45. Although any conventional material may be utilized, due to the nature of the parts a cheaper material such as white metal or brass may be used for disc whilethe separable blades may be made of any tool steel for temper. By referring to Fig. 7 it will be observed that the blades, as in the preferred form, have radial cutting edges which extend at their extremity to contiguous relation in the axis of the cutter.

A further modification is shown in Figs. 8 and 9 to include a disc 5| having an axial hole 52 for receiving the lead to be pointed, and having three radially disposed support angles 53 welded or soldered thereon. Each support angle 53 has an aperture 54 for accommodating screw 65 which extends through slot 44 of the blade of Fig. 5, fixedly to secure said blade when nut 56 is tightened. Good results have been obtained by utilizing 0-80 size machine screw and nut of brass. However, the invention is not to be limited to such detail as other dimensions may be practiced without departing from the spirit of the invention.

Although there are described embodiments utilizing a cap having a diameter greater than the diameter of the container, it is entirely feasible without departing from the invention to construct a pointing apparatus having a container of greater diameter than the cap. For example, Figs. 10 and 11 show diiferent forms involving such modifications. In Fig. 10 a three-sided container 51 has a. smaller circular cap 58; while in Fig. 11 a four-sided container 59 is provided with a smaller circular cap 60. As so modified, by referring to Fig. 12 it will be noted that neck 6| of a bottle 59 has spiral bead 62 for engaging internal groove 63 of cap 60 for tightening the cap thereon as the closure element, thereby rigidly assembling therebetween cutter 66 which may be of a form corresponding either to Fig. 3, Fig. 6, or Fig. 8.

Constructions as described above are capable of being cheaply manufactured to form durable mechanisms capable of attractive design in a variety of shapes. The operator will very soon learn the simple technique explained above for pointing the lead, and no difiiculty will be experienced in maintaining perfect points on the drafting implement regardless of its material.

What I claim is:

1. In a device for pointing a standard lead having a coaxial surrounding non-lead holder, a container, a. cap for the container, a plurality of lead pointing cutters rigidly fixed at the inner surface of the cap and relatively positioned each with respect to the other to taper-cut only the lead, an aperture in the cap of a size to receive the pencil lead with the top of said cap acting as an abutment for the holding means for said lead, the upper portions of said cutters defining an opening coinciding with and of the sazne size as said aperture.

2. In a device of the class described, a. container having an upper rim, 9. cap for the container, a cutter base of a size to engage said upper rim and held between the cap and said rim, pencil lead pointing cutters held by said base and in cutting position, an aperture in said base of a size to receive a pencil lead, and an aperture in said cap coinciding with said first mentioned aperture and of a size to receive a pencil lead with the top surface of the cap acting as an abutment for a holding means for the lead.

3. In a device of the class described, a container having an upper rim, a cap for the container, a cutter base of a size to engage said upper rim and held between said cap and said rim, integral pencil lead pointing cutters stamped out of said base and in cutting position, an aperture in said base of a size to receive a pencil lead, and an aperture in said cap coinciding with said first mentioned aperture and of a size to receive a pencil lead with the top surface of the cap acting as an abutment for a. holding means for the lead.

4. In a device of the class described, a container having an upper rim, a cap for the container, a cutter base of a size to engage said upper rim and held between said cap and said rim, integral lugs on said base, pencil lead pointing cutters held by said lug and in cutting position, an aperture in said base of a size to receive a pencil lead, and an aperture in said cap coinciding with said first mentioned aperture and of a size to receive a pencil lead with the top surface of the cap acting as an abutment for a holding means for the lead.

5. Inc. device of the class described, a container having an upper rim, a cap for the container, a cutter base of a size to engage said upper rim and held between said cap and said rim, lugs secured to said base, pencil lead pointing cutters detachably held by said lugs and in cutting position, an aperture in said base of a size to receive a pencil lead, and an aperture in said cap coinciding with said first mentioned aperture and of a. size to receive a pencil lead with the top surface of the cap acting as an abutment for a holding means for the lead.

STAFFORD H. JOHNSTON.

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