US2941508A

US2941508A - Marking pencil

Info

Publication number: US2941508A
Application number: US530993A
Authority: US
Inventors: Walter B Spatz
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-08-29
Filing date: 1955-08-29
Publication date: 1960-06-21
Anticipated expiration: 1977-06-21

Description

w. B. sPATz MARKING PENCIL June 21, i960 3 Sheets-Sheet l Filed Aug. 29, 1955 I N VENTO/e,

WAI-TEE 5P/#TZ ATTORNEY.

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June 21, 1960 Filed Aug. 29, 1955 A -rroRA/Ey United States Patent MARKING PENCIL Walter B. Spatz, 11182 Sunset Blvd., Los Angeles, Calif. Filed Aug. 29, 1955, Ser. No. 530,993

9 Claims. (Cl. 1Z0-15) This invention relates to a novel combination of pencil case and pointer, and more specifically is concerned with a case for receiving a marking pencil in conjunction with a pointer or sharpening means for said pencil. The instrument of the invention is specifically designed for use as and has its major utility as an eyebrow pencil.

Marking `or eyebrow pencils wherein a pencil is mounted in a case and a pointer its onto the case for sharpening the pencil are known. However, the prior art structures have certain disadvantages, one in particular being the rather complicated structure of such prior art devices. Another disadvantage of known devices is that they often do not function properly to produce a suiciently good pencil point and they also have a tendency to become clogged with pencil chips.

One object of this invention is' the provision of a pencil pointer, particularly an eyebrow pencil, which is of simplified structure compared to prior art devices.

Another object is 'to provide a pencil pointer having a pointer or sharpener of novel design which cooperates with the pencil and other structural elements of the instrument to maintain the pencil in position during the sharpening of the pencil point, `and which cuts a relatively sharp point and provides means for collection of chips and dust produced by the cutter away from the vicinity of the cutter to prevent clogging thereof.

A still further object is the design of a marking pencil or self-sharpening eyebrow pencil composed of a case for receiving the pencil and a pointer connected thereto, the instrument embodying a novel latching means to ensure proper positioning of the pencil in the case after removal of the cutter, but which is operative on mounting of the cutter on the case to unlatch the latching means to permit the pencil to move forward into engagement with the pointer for sharpening the pencil.

Yet another object of the invention is to design a pencil pointer of the aforementioned type which permits the sharpened end of the pencil to protrude a substantial distance beyond the case to facilitate the use of the pencil and avoid possible accidental contact of the case with whatever is being marked, e.g., the eyebrows.

Other objects and advantages of the invention will appear from the description thereof given below.

According to one form of the invention, a marking pencil is provided which comprises a case in the form of a hollow barrel open at its outer end, and a cap removably mounted over the barrel, the cap having a pointer mounted therein. The novel pointer of the invention is in the form of a hollow truncated cone having a cutter positioned in the cone, the pointer terminating at the plane of truncation to permit ready egress of small particles, and the like, from the pointer, the particles discharging both generally axially and laterally of the pointer axis. Preferably the cutter element is wedgeshaped and is formed integral with the cone. A slot is provided in the cone adjacent the cutter, and the cone is apertured at the apex thereof. As will be seen more clearly hereinafter, the apex of the pointer cone'is positioned e'ccentrically of the axis of the bore of the barrel and of the pencil or eyebrow crayon positioned therein, and the axis of the cone is disposed at a small acute angle to the axis of the barrel and the pencil. Thus,

when lthe pencil point is received in the cone of thev pointer, and the latter is rotated to sharpen the pencil` in the manner described more fully below, a load is imposed against the pencil, forcing it into engagement with a section of the cone essentially opposite the cutter edge, to thus limit lateral deflection or wobblng of fthe crayon, which is inevitable where the pencil is not supported against lateral deflection. yIn eifect a binding force is thus exerted `against lthe pencil as a result of the rotary cutting action of the pointer, to maintain the pencil in fixed position during sharpening. The slot in the cone of the cutter permits chips cut from the pencil to emerge into the cap, the slot being of such size that the chips do not fall back into the interior of the case, and the aperture at the plane of truncation of the cone permits small particles cut from the pencil to drop out of the pointer and pass freely into the gap and thus prevent clogging of the cone. l

A pencil support or pusher member in the form of an elongated slidable rod is mounted in the barrel for axial movement therein, the rod being adapted to support a pencil at one end thereof. A coil spring mounted clearance is provided between the pencil and the bore ofA the sleeve to permit slidable but nonrotatable motion of the pencil in the sleeve, with the end of the pusher rod in abutting axial alignment with the pencil. The coil spring normally urges the pusher rod and pencil toward the outer end of the barrel, to bring the pencil into operative engagement with the pointer when the cap is mounted over the barrel, as will be more clearly brought out hereinafter. l

The device of the invention incorporates a novel releasable latching mechanism for la-tching the pencil support or pusher .rod against movement when the cap is removed from the barrel, to thus prevent undesirable ejection of the pencil from the case while the pencil is in use, the latch being unlocked by the cap. According to one embodiment, the latch comprises a U-shaped portion thereof between the legs of the U-spring for receiving the pusher rod. The Uspring is iixed at one end, the other end of this spring abutting a key which is axially slidable inra groove on the outer surface of the nose or sleeve which houses the pencil and guides the pusher rod. When the cap is removed from the barrel, the intermedia-te portion of the latching spring is in frictional binding contact with the rod, and restrains axial movement thereof. When the cap is mounted over the barrel, e.g., by screwing the cap onto the nose piece, the edge of the cap contacts the slidable key, moving it axially and thus urging the latching spring into nonrestraining position with respect to the pencil support or pusher rod, permitting it to move freely under the action of the coil spring to push. the pencil into snug engagement with the cone of the pointer.

A cover member in' the form of a ring at all times covers the key adjacentthe outer end `of the barrel to prevent accidental actuationA 3 thereof by means other than the cap, eg. the fingers, during use of the pencil.

After the pencil has been sharpened, vthe `removal of the cap imparts a frictional drag on "the pencil or crayon rotating it so that its Ysurfaces .are forced against the surfaces of the sleeve or nose piece, providing a mild binding action between the pencil and sleeve. Nothing holds the pencil or crayon in the case after the cap is removed except the adhesive tension between the sides of the `crayon and sleeve, and between .the end of the crayon andthe abutting end of the ipusher rod. However, the amount of such adhesion is sufficient to hold .the pencil in the case .during use of the pencil following removal of .the cap, without the pencil falling out of the case.

The invention will be more clearly understood by reference to the following description of a preferred embodiment of my pencil pointer, taken in connection with the accompanying drawings wherein:

Fig. l is an enlarged longitudinal section through my pencil pointer, certain parts being shown in elevation for clarity;

Fig. 2 is an exploded isometric view showing certain components of the device;

Fig. 3 is .a section on line 3 3 of Fig. 1;

Fig. 4 is a perspective View of the key;

Fig. 5 is an enlarged detail of the latching Spring and pusher rod combination;

Fig. 6 is a View taken on line :6 6 of Figs. 1 and 5;

Fig. 7 is .an enlarged sectional view of a portion of .the device of Fig. l;

`Fig. 8 is an irregular section .on line 8-8 of Fig. 7;

Fig. 9 is a partial plan view taken .on line 9--9` of Fig. 7;

Fig. l0 is a section taken on line 10-10 of Fig. 7;

Fig. 1l 4is an enlarged cross sectional view taken on line 11--11 of Figs. yl and 12, looking into the cutter from the reardthereon Fig 12 is a longitudinal sectional view on line 12v-l2 ofFi'g. 11;

Fig. 13 is a section taken on line 13-13 of Fig. 12; and

Fig. 14 is a plan view taken on line 1F14 of Fig. 12..

Referring particularly to Fig. 1, the pencil case 20 comprises an elongated hollow barrel 22 open `at one end 24, and over which is .adapted to .be positioned a removable cap 26 `having ,a sharpening means or pointer 28 mounted therein.

A nose or sleeve 30, see Figs. 1, 2, 7, 8 and 10, is mounted at the forward Iopen end of the barrel Z2 by inserting the rear portion `44 of the nose piece into the barrel, the bore 38 of the barrel being provided with a ri-b 32 which engages a groove 34 in the nose piece to hold the same in fixed axial position in the barrel bore. The bore 38 of the barrel also carries a pair of diametrically opposed lugs 40 on the inner periphery thereof, the `lugs mating with .diametrically opposed longitudinal slots 42 on the rear portion 44 to prevent rotary motion of the nose piece 30.

The nose piece 30 .comprises ,an enlarged outwardly tapering forward portion 50, an intermediate `flange 52 and the rear portion 44. Portion 44 I(see Figs. 7, 8 and 10) has a lower longitudinally extending groove S4 therein .andan upper 'longitudinal lgroove 56. The upper portion of fiange 52 (see Fig. 2) is cut back to form a narrow dla'nge 58 and a pair of spaced lugs 60 (see Figs. 7 and l8) are positioned on the top of the nose piece and separated :a short .distance from the upper ange 58. The nose piece 30 has :an internal bore 62 extending from end to end of said nose piece or sleeve. The cross secti'on of the bore is non-,circular .or pentagonal, as indicated in Figs.V 8 .and 10, with straight sides 64. The front portion 50 of the nose piece `is threaded as at 66 to receive cap 26.

`A pencil support or pusher rod 68 is mounted axially vthe barrel ZZ, and is supported for axial movement therein by positioning one end 69 of the rod in a pocket 70 formed at the closed narrow end 71 of the barrel. The rod 68 is cylindrical and is received within the pentagonal bore 62 of nose piece 36. The forward end 72 of the pusher rod is received in bore 62 with sufficient clearance to permit l.axial displacement of the rod within said bore. A .pencil or crayon 73 having a non-circular or pentagonal cross section is matingly received yWithin bore 612 so as to permit axial movement of the pencil in the bore. The at end of the pencil abuts the end 72 of the pusher rod .as at 75. 'It is seen Ithat while the crayon 73 is slidable longitudinally in the bore 62 of the nose piece 30, the mating pentagonal or non-circular surfaces of the crayon with said bore prevents rotary motion of the crayon. A compression spring 74 is seated in pocket 70 about .the end 69 of the pusher rod, ,the spring abutting a -ange 76 .on the rod and normally urging the rod and the pencil forward, to bring the point 7S of the pencil into operative engagement with .the pointer 28.

The pusher rod 68 is provided with a releasable latching mechanism designated generally by the numeral 79, and .comprising 'a U-shaped latching spring 80, note particularly Figs. 1, 5, 6., .and 7, having one leg 82 longer and wider than the other leg 84, and an intermediate portion 86 .bent at an acute angle somewhat less .than 90 yto `leg 82, .and at an obtuse angle somewhat greater than 90 to leg 84. The intermediate portion S6 is enlarged to provide an aperture 88 therein .to receive the pusher rod 68, sufficient clearance being provided to permit the rod to move axially t-hrough said aperture with respect to portion 8K6 of the spring 80.

Leg 82 of spring 80 is positioned in the upper groove 56 formed in portion 44 of nose piece 30, and the outer end of the spring leg 82 is provided with ears 90 which are positioned between lugs 60 of nose piece 30, and the ange 58 (see particularly Figs. 7, 8 and 9), to secure leg 82 of the U-spring in position to prevent axial movement of leg 82. The outer edges of spring leg 82 at its junction 91 with the intermediate spring portion 86 are in abutting relation at 93 with the wall of bore 38 of the barrel, thus preventing displacement of spring leg 82 upwardly as viewed in Figs. 1 and 7. Leg 84 of spring 80 is positioned in the lower. groove 54 of the nose piece 30, and the outer end of leg 84 is urged at 92 into abutting contact with a key 94. The key (see Fig. 4) has a large base portion 9 5 which carrim a shallow step member 96 of a width and length shorter than the width and length of base portion 9S. The base portion of the key slides in the lower groove or slot 54 in portion 44 of the nose piece 30, and the step member 96 slides in a shallow groove 97 of nose portion 44, the latter groove communicating with groove 54. The free end of the leg 84 of spring 80 rides at the upper end 98' of groove 54 in front of key 94, and the provision of the step member 96 on the key, which occupies groove 97, prevents the end of spring leg 84 from jamming into groove 97 between the key and the nose piece. The base portion of the key is provided with an end portion 99, a shallow stepped end portion 101 and an intermediate notch 103 permitting the key to slide over the rib 32 on the wall of the barrel bore 38. The shoulder 99 on the end portion 99 of the .key (see Fig. 7) limits longitudinal motion of the key.

The intermediate portion 86 of spring 80 extends beyond the rear portion of nose piece 30. When the spring 80 is in normal position, the opposite peripheral edge portions 98 of the aperture 88 in the central portion 86 of the latching spring (see particularly Figs. 5 and 6)V abut the adjacent peripheral portions 100 of the pusher rod 68, causing a binding action between these contacting surfaces of the rod and spring, and holding the rod 68 in latched position to prevent axial movement thereof under the action of coil spring 74.

However, when the key 94 is urged to the right as viewed in Figs. 1 and 7, the leg 84 of the spring 80 is pushed forward, causing the spring 80 to ex in Aa direction,

to rotate the intermediate portion 86 of the spring, as seen in Figs. 1, 5 and 7, counterclockwise about 91 as a fulcrum point, thus freeing the

surfaces

98 and 100 from contact with each other, and unlatching the pusher rod from its xed position with respect to spring portion 86 and permitting the pusher rod 68 to move freely in an axial direction through the aperture 88 in the central portion 86 of said spring. A ring 102 is pressed fitted about

ianges

52 and 58, and about the outwardly extending portion 99 of key 94, thus covering the exposed portion of the key extending beyond the open end 24 of the barrel, and preventing accidental actuation of the key by the lingers while handling the case.

Cap 26 containing the pointer 28 has internal threads 104 which mate with the external threads 66 provided on the forward portion 50 of the nose piece 30, providing a cam interconnection for securing the cap to the nose piece and over the open end 24 of the barrel 22. When the'cap is screwed onto the nose piece, asviewed in Figs. 1 and 7, a anged end portion 106 of cap 26 passes under ring 102 and makes contact with the key 94, urging it to the right and unlatching the latch spring 80 as described above, permitting coil spring 74 to urge the pusher rod 68 and the pencil or crayon 73 to the left, and thus urging the point 78 of the crayon into the pointer 28.

Viewing Figs. .1, 2, 1l, l2, 13 and 14, the pointer 28 is mounted on a cylindrical support 109 press fitted into the interior of cap 26 and abutting a shoulder 111 therein. 'Ihe pointer is in the form of a truncated hollow cone 110 having a slot 112 intersecting the surface of the cone and connecting the interior of the cone with the exterior of the cone, one edge 114 of the slot being defined by the surfaces 115 of a wedge 116 formed integrally with the cone. The edge 114 of the wedge forms a cutter edge and protrudes a short distance as at 118 into the interior of the hollow cone beyond the interior conical surface 119 of the cone. The truncated cone is apertured at 120 in a plane perpendicular to the axis of the cone, the wedge 116 extending upward beyond said plane and through said aperture to a point 121. Apex 123 of the cone (see Fig. 12) is eccentric of the axis Y of the barrel and of the crayon positioned in said barrel, and the axis X of the cone is tilted about one degree to the Y axis. The wedge 116 is in the shape of a frustum of an oblique pyramid, i.e. the triangular cross section of the wedge 116 increases in area from the outer end thereof towards the cone and intersects the cone to produce a at inner surface 121 adjacent the inner surface 119, and the protruding cutting edge 114 at the face of the slot. The wedge 116 also gives mass and rigidity to the cutter permitting the rest of the cone to be of light construction.

It is thus seen that as the cap is rotated and screwed onto the nose piece 30, the pointer and cone 110 thereof are also rotated to sharpen the point 78 of the crayon as it is urged into the cone by the pusher rod 68 under the action of spring.74, forming a conical point 78 on the pencil or crayon. During this sharpening period, because of the eccentricity of the apex of the cone and the tilting of the axis of the cone with respect to the axis of the barrel and th pencil or crayon 73, a load is exerted downwardly against the crayon, as viewed in Figs. l, 7 and 12, to press the pencil 73 near the base of the conical point against the adjacent lower section 110' of the cone 110 in nosepiece 30. This action tends to hold the pencil or crayon firmly within the cone to prevent excessive bending load on the pointed end and to prevent the crayon breaking at this weakened section.

Due to the tilting of the axis X of the cone 110 and the position of the cutter edge 114, the region 110' where contact is made with the crayon is not necessarily diametncally opposite to the cutter 114. As the cutter is rotated it bites into the crayon to cut a chip thus introducing a lateral force on the crayon. Since the cutter edge 114 travels around the crayon the cutter tends to cause a circular wobble of the crayon. The degree of wobble is materially reduced from that which would be produced by the cutter if mounted in a cone which was axially coincident with the crayon and with a cutter protruding into the interior of cone to the depth cut desired. I, however, materially reduce this degree of wobble by radially displacing the apex of the cone from the axis of the barrel land crayon, as shown in Fig. 12. The extent to which the apex is displaced controls the degree to which the wobble is reduced. In a practical observation I have found that a displacement of approximately half the depth of cut produces optimum results in that it minimizes the degree of wobble and the eflciency of cut is maintained.

The slot 112 of the pointer cone 110 is made narrow, and is of a dimension such that it is sufficiently l-arge -to permit chips cut from the pencil to pass into the cap 26, :but is small enough to prevent these chips from dropping back into the cone 110. It is to be noted that the frustoconical member terminates at its plane of -truncation and that the only pointer portion extending forwardly beyond the plane of truncation is the cutter wedge 116, which is of comparatively small arcuate extent. As a result, the forward end of the aperture terminates substantially at the plane of truncation, communicating freely and directly with the interior of the surrounding cap, enabling relatively small particles of crayon, dust, debris, and the like, to pass easily out of the forward end of the aperture, for lateral dropping into the cap. The major portion of the cuttings pass laterally out of the conical member 110 through the slot 112, the termination ofthe member 110 at its plane of truncation allowing the small particles to move readily out of the end of the opening 120 and preventing their packing in the interior of the member 110'. It-is seen -that except for the slot 112 and aperture y120, there is no communication between the interior of the cap 26 and the exterior of the cap, the outer end of which is provided with a removable closure 122 (see Figs. 1 and 2).

The closure 122 has -a bore 124 and comprises an enlarged closed cylindrical end portion 126 and an open end portion 128 providing communication between the interior of the cap and the bore 124. Between

end portions

126 and 128 is a stepped shoulder 130 which mates with the stepped end 132 of the cap 26, and the end portion 128 of the closure 122 has a pair of diametrically opposed pins 134 thereon, which are adapted to slide in diametrically opposed slots 136 positioned on the inner wall at the end of cap 26 (see also Fig. 3),- when the closure is tted onto the cap, with the end portion 128 of the closure sliding into the end of the cap as seen in Fig. l. When the stepped shoulders and 132 of the closure and cap are in abutting relation, the pins 134 will have moved to the right end of slots 136, as seen in Fig. l, 4and rotation of the closure will lock the closure onto the cap by abutment of the pins with the shoulder 138 on the inner surface of the cap 26.

When the cap 26 is unscrewed from the nose piece 30 following the sharpening operation, the intermediateportion 86 of latching spring 80- will be rotated clockwise about fulcrum point 91 of lthe spring, urging leg 84 of the latching spring land the key 94 to the left as viewed in Figs. 1 and 7, latching the pusher rod 68 so that it is restrained against outward movement as `described above. The removal of the cap 26 causes the pointer 28 to impart a. frictional drag on the crayon 73, rotating it so as to -force its apices at the intersection of the plane surfaces thereof against the flat surfaces of the mating pentagonal bore 62, to produce a wedging action tending to hold the crayon in the bore after the cap is removed. Also, when the cap is entirely removed, the crayon is further restrained against axial movement out of the pencil case by adhesive Itension at 75 between the flat end of the tacky crayon and the abutting end of pusher rod 68. v

The crayon, following the removal of the cap, protrudes a substantialdistance beyond the forward portion substantial rotation relative to said barrel while permitting the pencil to move axially of said barrel; feeding means in said barrel for engaging and urging the pencil in a direction forwardly of said barrel to locate the for- 'ward end portion of the pencil externally of the barrel;

a cap; means mounting said cap for longitudinal movement and rotation on said barrel; cutter means having a cutter edge and secured to said cap and rotatable therewith when said cap is mounted on said barrel to engage said cutter edge with the forward end portion of the pencil and cut and sharpen the same; releasable latch means disposed completely within said barrel and normally engaging said feeding means to prevent said feeding means from moving the pencil longitudinally in said barrel, said latch means including an operating member entirely within and extending lengthwise of said barrel; said cap having a portion extending into said barrel which engages said operating member when said cap is mounted on said barrel to move said operating member lengthwise of said barrel and release said latch means from said feeding means to permit said feeding means to urge the pencil in said forward direction against said cutter means.

7. In a marking pencil: a barrel having means engaging a pencil for supporting the pencil in said barrel against substantial rotation relative to said barrel while permitting the pencil to move axially of said barrel; feeding means in -said barrel for engaging and feeding the pencil in a direction forwardly of said barrel to locate the forward end portion of the pencil externally of the barrel, said feeding means including an elongate member; a latch member having an opening through which said elongate member passes, said latch member normally occupying a position in said barrel in which a side of said latch member defining said opening grips said elongate member; a cap; means mounting said cap for longitudinal movement and rotation on said barrel; cutter means having a cutter edge and secured to said cap and rotatable therewith when said cap is mounted on said barrel to engage said cutter edge with the forward end portion of the pencil and cut and sharpen the same; an operating member operatively connected to said latch member and extending lengthwise of said barrel and engaged by said cap when said cap is mounted on said barrel to move said operating member lengthwise of said barrel by said cap and release said latch member from said elongate member to permit said feeding means to urge the pencil in said forward direction.

8. In a marking pencil: a barrel adapted to contain a pencil; feed means in said barrel engageable with the pencil to urge the pencil in a direction forwardly of said barrel to locate the forward end of the pencil externally of the barrel, said feed means including an elongate member; a latch member having a transverse portion provided with an opening through which said elongate member passes and a les Portion integral with said transverse portion and extending lengthwise of the barrel; means normally positioning said transverse portion in inclined relation to said elongate member to cause the side of said transverse portion defining said opening to grip said elongate member; a cap removably mounted on said barrel to cover the forward portion of the pencil; and means operatively engaging said leg portion and engaged by said cap when mounted on said barrel for changing the inclination of said transverse portion to release said side from gripping engagement with said elongate member.

9. In a marking pencil: a barrel having means engaging a pencil for supporting the pencil in said barrel against substantial rotation relative to said barrel while permitting the pencil to move axially of said barrel; feeding means in said barrel for engaging and feeding the pencil in a direction forwardly of said barrel to locate the forward end portion of the pencil externally of the barrel, said feeding means including an elongate member; a cap; means mounting said cap for longitudinal movement and rotation on said barrel; rotatable cutter means having a cutter edge secured to said cap and rotatable therewith when said cap is mounted on said barrel to engage said cutter edge with the forward end portion of the pencil and cut and sharpen the same; self-energizing, one-way latch means normally engaging said elongate member to prevent said feeding means form moving the pencil longitudinally in said barrel, said latch means being adapted to increase its gripping engagement against said elongate member as said member tends to move forwardly of said barrel, said latch means automatically releasing to permit rearward movement of said elongate member in said barrel, said latch means including an operating member extending lengthwise of said barrel and engaged by said cap when said cap is mounted on said barrel to move said operating member lengthwise of said barrel by said cap and release said latch means from said elongate member to permit said feeding means to urge the pencil in said forward direction.

References Cited in the file of this patent UNITED STATES PATENTS 527,803 McCollum Oct. 23, 1894 578,577 Moseley Mar. 9, 1897 1,601,118 Hassenfeld Sept. 28, 1926 1,780,581 Dillier Nov. 4, 1930 2,000,487 Koch May 7, 1935 2,303,273 Hendrick Nov. 24, 1942 2,486,960 Mesh et al Nov. 1, 1949 2,507,089 Bridges et al. May 9, 1950 2,565,715 Becker et al Aug. 28, 1951 2,604,877 Glass et al July 29, 1952 2,624,316 Blanco et al. Ian. 6, 1953 FOREIGN PATENTS 1,014,921 France June 25, 1952