US 2942577 A
Description (OCR text may contain errors)
June 28, 1960 B. SOLOW PENCIL MARKING POINT 2 Sheets-Sheet 1 Filed May 17, 1955 l a Pi Wflfiw 7%. N 5 N m 5 B. SOLOW PENCIL MARKING POINT June 28, 1960 Filed May 17, 1955 2 Sheets-Sheet 2 w m I lllllllIl/ IN V EN TOR. [/V-/,4M//V $01 014 BY 14 Tram/B.
\ Z I i I HMW\\\\\\ Ill/II United States Patent 2,942,577 PENCIL MARKING POINT Benjamin Solow, Philadelphia, Pa. (5743 Rhodes Ave., North Hollywood, Calif.)
Filed May 17, 1955, Ser. No. 508,957
2 Claims. (Cl. 120-83) This invention relates to novel pencil marking-points and to a method and apparatus for making such marking points.
For many years pencil manufacturers have sought a mechanical lead pencil that would provide a sharp point, which sharp point would not be dulled after the initial Writing period.
A suggested solution to this problem is the magazine form of mechanical pencil, namely pencils in which a series of sharp points are contained in a magazine, and in which means are provided for ejecting worn points and substituting new ones therefor. A number of United States patents have been granted on such devices, such as Fornander Patent 499,191, issued June 6, 1893; Goldsmith Patent 618,172, issued January 24, 1899, etc.
However, the magazine pencil has never proven commercially practicable. The salient reason for the failure of this pencil lies in the fact that it has not been possible to provide a sharpened pencil lead having adequate structural strength. Thus, the pencilleads are subjected to stresses and strains in manufacture and assembly, particularly during the magazine loading operation, in transport, and while positioned within the pencil, etc. causing the points to shatter, split, or become dull. As it has not heretofore been possible to provide a pencil markingpoint having adequate strength, the magazine form of pencil has not been commercially exploited.
This invention has as an object the provision of a pencil marking-point for use in a magazine pencil, which marking-point possesses great structural strength.
A further object of the present invention is the provision of a method of manufacturing pencil marking-points V possessing great structural strength.
Another object of the present invention is the provision of apparatus for making pencil marking-points of great strength.
Still further objects will appearhereafter.
For the purpose of illustrating the invention there are shown in the drawings forms which are presently preferred; it being understood, however, that this invention is not limited to the present arrangements and instrumentalitiesshown.
Referring to the drawings,-wherein like referencecharacters refer to like parts. i
Figure 1 is a perspective view of one embodiment of the pencil marking-point of the present invention.
Figure 2 is a part elevation and part longitudinal sec- I tional view of'a split tube magazine of the present invention showing a plurality of pencil 'marking-points nested together.
Figure 3 is a fragmentary enlarged sectional view of a portion of Figure 2 showing the relationship of the pencil marking points nested together.
Figure 3a is a vertical sectional view of a modified embodiment of the pencil marking-point of the present invention.
Figure 4 is a perspective view of an embodiment of a mold for forming the pencil marking points of the pres ent invention.
Figure 5 is a longitudinalsectional view of the sheet metal plate used to form the support collar for the pencil marking-points of the present invention. Figure 6 is a fragmentary sectional view through the sections of the mold with the mold sections in operative alignment, and with a pencil marking-point formed therebetween.
Figure 7 is a diagrammatic sectional view of the punching-out stage in the manufacture ofthe'pencil markingpoints of the present invention.- Referring to the drawings, and initially to" Figures 1', 2 and 3 the pencil marking-point of the present invention is designated 10. Marking-pointlll comprises a sheet metal tubular collar IZand a pencil lead 114."Pen' cil lead 14 has a sharp conical point 16 surrounded by an an'nula'r'flat 17 at one end,-and a cone-shaped cavity 18 at the other end, surrounded by an annular flat 19. The tubular collar 12 has an inwardly directed flange 21' which covers'a portion of flat 17. The cone-shaped cavity 18 is of a size sufficient to form 'a nest for the tip portion of the point 16 of a similarly shaped pencil lead 14 so that internesting or sheathing of a plurality of pencil points may be accomplished in vertical alignment within a split tube magazine 23 (see Figures 2 and 3) As seen particularly in Figure 3, when the marking points are internested, flange 21 of each upper marking point rests on'the annular upper edge 24 of thenietal collar 12 of the next lowermarking-point. There is a gap between point 16 of each upper marking-point and cavity 18 of each lower marking-point. In this-manner all longitudinal thrust is borne by the metal collar 12 and not by lead 14 when the marking points are internested.
Themetal tubular collar 12"servesas a shield protect-- ing pencil lead 14 from shock, when the marking-point 10 is grasped at its side within the magazine23. The internesting of point 16 of the pencil lead 14 of one markingpoint 10 within the cone-shaped cavity 18 of the pencil lead 14 of another marking-point 10 leads to'further structural strength as the points 16 are protected by the pencil lead 14 and metal tubular collar 12 of the marking-point within which the point 16 is received. Y
The method and apparatus for manufacturing the pencil marking-points of the present invention can be ascertained from an examination of Figures 4' through '7, wherein the manufacture of the pencil marking-point 10 is illustrated.
One embodiment of the mold used in the present invention is diagrammaticallyillustrated in Figure 4. The mold designated generally as 50 comprises an upper or cap section 52 and a lower or bottom section 54. The
sections 52 and 54 are provided with respective mating conical knobs and cavities, so that when upper section- 52 alignedly rests on the upper surface of lower section 54, each cavity 53 formed in lower section 54receives a mating conicalknob' 55 of uppersection 52'.-
x The cavity 53 in lower section54 includes a'do'wn'- wardly directed cone-shaped recess 56-which forms the sharp conical point 16 of'pencil lead 14, and a surround ing or contiguous plateau 57-'on which flange 21 rests. Conical knob 55 is smaller than the" mouth of cavity 53 in lower section 54 andforms cone-shaped cavity 18 in pencil lead 14. Surrounding conical knob 55 is a raised contiguous plateau 59 which forms fiat 19 in pen-, cil lead 14. A sheet metal plate 60 of thin sheet metal (see in particular, Figure 5) having annular flanges 62, which serves as a metallic liner (see Figure 6) is fitted over bottom section 54. As shown in Figure 6, plate 60 covers the surface of bottom section 54, except for the cone-shaped recesses 56 and the plateaus 57.
The conventional components used in forming pencil leads, such as aplasticized. mass of finely divided graphite, soot and clay are placed in the space between the depending annular flange 62 and the cone-shaped recess 56 in eachof the cavities 53 of bottom section 54. Sufficient pencil lead component composition is included so that whenmold section 52 is placed over mold section 54, the pencil lead components fill the cavity intermediate upper section 52 and lower section 54.
No claim is made to novel pencil lead compositions. Accordingly, conventional. pencil lead compositions may be used. Straight Patent 2,388,447; Ferst Patent 2,355; 639; Van Dusen Patent 2,566,753; Loy Patent 2,645,582; ManevalxPatent2,679,460 and Loy Patent 2,682,476 disclose various pencil lead compositions. The plasticized pencil lead composition shaped in the aforesaid manner may be dried within the mold and then fired at conventionally used firing conditions.
Whenthe temperature of the mold has been returned to room temperature, upper section 52 is raised from lower section 54 and plate 60 carrying the hardened pencil marking-points is removed from lower section 54.
The plate is then positioned on a suitable multipunch press 70 having a plurality of punches 72 (see Figure 7).
As shown in Figure 7 the pencil marking-points of the present invention are cut away from plate 60 on the downward movement of punch 72 (see top arrow in Figure 7). The cut-away pencil marking-points 10 fall downwardly in the direction of the bottom arrow, and are collected at the bottom of the press 70.
Preferably, the split tube magazine 23 is positioned immediately below the openings in multipunch press 70 so that the movement of punch 72 pushes the cut-away pencil marking-points directly into the split tube magazine 23.
In the embodiment shown in Fig. 3a, the pencil marking-point includes a collar 12a and a pencil lead 14a. Collar 12a is crimped somewhat at 15, so that it partially projects into pencil lead 14a. The inward projection 15 of collar 12a serves as a thrust pillow and retention stop absorbing longitudinally directed stresses.
Pencil lead 14a is provided with a point 16a, and a cone-shaped cavity 18a surrounded by an annular flat 4 19a. The lower end of collar 12a is provided with an inwardly directed flange 21a.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes. thereof, and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification as indicating the scope of the invention.
Having thus described my invention I claim:
1. A pencil marking-point including a pencil lead consisting of a writing material having a generally cylindrical body portion, a conically tapered point at one end of said pencil lead, a cone-shaped cavity at the other end of said pencil lead, with the apex of said cone-shaped cavity disposed on the longitudinal axis of the pencil lead, the walls of said cavity conforming to the outer shape of the conically tapered point, whereby a conically tapered point of a similarly formed pencil lead' may be nested therein, an open-ended tubular imperforate metal collar circumferentially embracing the body portion of the pencil lead, with said conically tapered point of the pencil lead projecting through one open end of said collar, and with said. one end of the collar having a radially inwardly directed flange covering a portion of the pencil lead contiguous to said conically tapered pencil lead point, with the portion of said pencil lead point intermediate said flange and the tip of the pencil lead comprising the conically tapered point, and with said conically tapered point projecting through and beyond said one end of said collar, and with the other end of the collar adjacent to the coneshaped cavity in the pencil lead extending a spaced distance beyond the end of the pencil lead which has the cone-shaped cavity, whereby a plurality of marking-points may be arranged tandemwise with the conically tapered point of one being received within the cone-shaped cavity of the other, and with the sole engagement between such marking-points being the metal to metal contact of the radially inwardly directed flange of one to the other end of the collar of the other so that thrust on the pencil lead is avoided.
2. A pencil marking-point assembly including a tubular magazine, and a plurality of similar pencil marking-points arranged therewithin tandemwise and in the same direction, each pencil marking-point including a pencil lead consisting of a writing material having a generally cylindrical body portion, a conically tapered point at one end of said pencil lead, a cone-shaped cavity at the other end of said pencil lead, with the apex of said cone-shaped cavity disposed on the longitudinal axis of the pencil lead, the walls ofsaid cavity conforming to the outer shape of the conically tapered point, an open-ended tubular imperforate metal collar circumferentially embracing the body portion of the pencil lead, said conically tapered point of the pencil lead projecting through one open end of said collar, the other end of said collar extending beyond the end of said pencil lead having said cone-shaped cavity, a radially inwardly directed flange covering a portion of the lead contiguous to said conically tapered point, with the portion of said pencil lead'point intermediate said flange and the tip of the pencil lead comprising the conically tapered point, the other end of the collar extending beyond the end of said pencil lead having said cone'shaped cavity, with the tip of the conically tapered point of the pencil lead of one marking-point nested within the cone-shaped cavity of the pencil lead of another marking-point, and with the radially inwardly directed flange of the former marking-point operatively engaging the outwardly extending end of the collar of the latter marking-point, whereby the pencil lead portion of each of said marking-points is spaced from the pencil lead portion of each adjacent marking-point.
References Cited in the file of this patent UNITED STATES PATENTS 468,744 Greenwald Feb. 9, 1892 1,278,147 Hess Sept. 10, 1918 1,669,342 Mayol May 8, 1928 2,302,045 Neurnann et al. Nov. 17, 1942 2,465,597 Marsh Mar. 29, 1949 2,493,665 Gagnon Jan. 3, 1950 2,528,385 Morn Oct. 31, 1950 2,582,922 Crawley Jan. 15, 1952 2,638,632 Glazer May 19, 1953 2,708,288 Fuller et al May 17, 1955 FOREIGN PATENTS 302,836 Great Britain Dec. 27, 1928 719,763 France Nov. 23, 1931 985,928 France Mar. 21, 1951