US3101073A

US3101073A - Mechanical pencil

Info

Publication number: US3101073A
Application number: US161605A
Authority: US
Inventors: Charles E Baird
Original assignee: Individual
Current assignee: Individual
Priority date: 1961-12-22
Filing date: 1961-12-22
Publication date: 1963-08-20
Anticipated expiration: 1980-08-20

Description

Aug. 20, 1963 c. E. BAIRD MECHANICAL PENCIL Filed Deo. 22, 1961 2 Sheets-Sheet 1 c. E. BAIRD MECHANICAL PENCIL Aug. 20, 1963 2 Sheets-Sheet 2 Filed Dec. 22, 1961 United States Patent() 3,101,073 MECHANICAL PENCIL Charles E. Baird, 500 Coronado Court, Paducah, Ky. Filed Dec. 22, 1961, Ser. No. 161,605 Claims. (Cl. 1Z0- 11) This invention relates to -a novel mechanical pencil.

The primary object yof the invention is the provision of a more eicient and more easily operated mechanical pencil wherein its lead, such as grease lead, is adapted to be pushed out from a spring-retracted protected position to a use position, and to be retracted from use position to retracted position by release of a spring-pressed catch which serves also to maintain the lead in use position, the lead being adapted to be extended, when worn, by screw means. As a result to these provisions the time and labor consuming inconveniences of prior grease lead pencils which do not provide for semi-automatic retraction of their leads from use position, but require manual retraction of the leads, and do not provide instant push extension of the leads to use position, are eliminated, as well as the tendency of the users of prior pencils to return these pencils to the pocket with the leads in extended use positions and soil the pocket.

Another object of the invention is the provision of a mechanical pencilV of the character indicated above. wherein a rotary push rod serves as the means for pushing out the lead to use position, and -as the means for rotating the screw means for extending or feeding and retraoting spring means serves to retract the lead.

A further object of the invention is the provision of a simple and rugged mechanical pencil of the character indicated above, wherein the catch is associated with and is partially housed by a pocket clip.

Other important objects `and advantageous features of the invention will be apparent from the following description yand the accompanying drawings, wherein, for purposes of illustration only, a specific form of the invention is set forth in detail.

In the drawings:

yFIGURE l isa side elevation of a mechanical pencil of the present invention, showing the lead in extended use position in phantom lines;

FIGURE 2 is atop plan view of FIGURE l;

FIGURE 3 is a longitudinal section taken on the line 3-3 of FIGURE 2, showing the lead in retracted position;

FIGURE 4 is a longitudinal section, partially in elevation, taken on the line 4-4 of FIGURE 3;

FIGURE 5 is ya view, similar to FIGURE 3, showing the lead in extended use position;

FIGURES 6 and 7 are enlarged transverse sections taken on the lines 6-6 and 7--7 of FIGURE 3; and

FIGURE 8 is an enlarged transverse section taken on the l-ine 8-8 of FIGURE 1.

Referring in detail to the drawings, wherein like numerals designate like parts throughout the several views, the illustrated mechanical pencil comprises a tubular cylindrical barrel 10 having a lower end 12 and an upper end 14, the barrel being externally rounded at itsupper end, as indicated at 16. The barrel 10 has a uniform diameter main bore 18 which extends upwardly from the lower end 12 to a point near to and spaced from the upper end 14, where a reduced diameter axial bore 20 extends from the upper end 14 and opens to the main bore 18.

lThe main bore 18 is formed with a pair of longitudinal diametrically opposed slide grooves 22 which extend downwardly from a location near to and spaced from the reduced bore 20, through -a short internally threaded portion 24, which extends to the lower end 12 of the barrel 10. -A tubular cylindrical pencil tip or point 26 is provided, which is larger in diameter than Ithe main bore 18 of the barrel 'and has a reduced externally threaded portion 28, on its upper end, which threads into the threaded pontion 24 of the barrel, and denes a shoulder 30 adapted to abut the lower end of the barrel. The tip 26 is provided with an axial bore 32 which extends therethrough and which is larger in diameter than relatively large diameter grease lead 34, which is initally longer than the tip 26.

1A split tubular spring lead holder 36, which is initially smaller in diameter 4than the lead 34, is adapted to expand on insertion of a lead therein and then having a close but free sliding t in the tip bore 32. The lead holder 36 is preferably somewhat longer than the tip 26 and has, on its upper end, `a lateral annular ilange 38, against which yan `annular washer 40 bears. A lead retracting coil spring -42 is circumposed on the lead holder 36 and is compressed between the washer 40 and the upper end 44 of the tip 26.

A relatively short cylindrical pusher block 46 slides in the main barrel bore 18 and has diametrically opposed lateral lugs 48, which slide in the slide grooves 22 of the bore 1S and prevent rotation of the pusher block relative to the barrel 10. The spring 42 keeps the lead holder ange 38 pressed `against the lower side of the pusher block 46, and the upper side of the pusher block bears `against the lower end 50 of a rotatable cylindrical push rod 52.

The pushrod 52 is longer than the distance, at any time, between the pusher block 46 and the upper end 14 of the barrel 10, and comprises la main portion 54 which rotates freely in the main barrel bore 18 and a reduced diameter, knurled upper end portion or knob S6 which rotates in the reduced bar-rel bore 20, whereby, `at all times, a p0rtion of the 1knob 56 extends upwardly from the upper end 14 of the barrel 10. An external annular groove 58 is provided at the upper end of the main push rod portion 54, in which a metal band 60 is seated and suitably secured, flush with the exterior of the portion 54. The band 60 has an internal annular flange 62, at its upper end, which covers the shoulder 64 at the upper end of the main rod portion 54.

The main push rod portion 54 is provided with an axial blind bore 66 which extends to its lower end 50 and has a closed upper end `63 Iat the upper end of the push rod. The blind bore 66 is flat and extends diametrically of the rod portion 54 and has dat parallel sides 63 and concavely lrounded edges 70, so as to conormably and non-rotatably receive ya similar cross section lead feeding `and retracting sorew 72 having flat parallel sides 74 and oonvexly curved screw-threaded edges 76. The screw 72 is preferably slightly longer than the blind bore 66, `and its lower portion is threaded through a threaded bore 73 in the pusher block 46. Clockwise rotation of the push rod 52 by means of the knurled knob 56- produces downward movement of the screw 72, and hence of the lead -34 relative to holder 36, and extends the lead 34 out of the holder 36 in order to compensate for wear of the lead 34 entailed in marking or writing therewith.

The lead 34 is extended from the retracted protective position shown in FIGURE 3 to the extended position shown in FIGURE 5, simply by pressing downwardly on the push rod knob 56, `and the push nod 52 is held releasaibly in this extended position, by means of a springpressed catch lof a pocket clip and catch assembly 78.

The assembly 78 comprises a preferably metal split band 80 which encircles the barrel 10, adjacent to the upper end 14 thereof, Iand is secured thereto, and has a longitudinal slot 82 therein, whose edges S4 bear retainably against the outer surfaces of longitudinal latenally outwar ly extending flanges Se, which are seated in gnooves 88, in the :outer surface of the barrel 1l), and which are portions lof the parallel side walls 9h Lof the channelashaped upper portion 92 of a downwardly extending pocket clip 94. The portion 92 has )a web or top wall 95 which extends between the side Walls 9d and which has an upper end portion 96 which curves upwardly and i laterally inward-ly to the barrel 10, and has an upper edge 98 which is securaoly engaged in a` transverse groove 16MB in the barrel 1t). The gnooves 58 are part of an elongated external recess 1632 in the barrelwhich extends downwardly from the transverse groove 160. Extending downwardly from the upper portion 92 of the pocket clip 94 is a clip arm 164, of limited ilexibility, which is of shallow channel cross section, the side wallslll and the web 168 of the clip arm 104 being continuations tof the side walls 90 and web 94 of theupper clip portion 92 of the clip.

The lower end of the web 108 or the clip arm 104 terminates Vin a laterally inwardly and upwardly convexed curved hollow tip 110, which bears against the exterior of the barrel lll.

The assembly 78 further comprises `a catch 112, of relatively thin flat stock, which comprises a longitudinally elongated finger piece 114 having intermediate its ends a zdownwardly.extending !fulcrum lug 116 which is seated in ia small depression 11S in the bottom 120 of the recess.

The upper part of the catch finger piece 114 works through a longitudinally elongated slot 122 provided in the curved portion 96 of the web 95 lof the pocket clip '78, `and extends upwardly beyond the .'clip. The finger piece 114 has a downwardly extending detent 124, on its lower end, which works through a slot 126, formed through the bottom of therecess 162, near the lower end of the recess. The detent 124 has a lower edge 123 which, in the engaged position of the catch 112 is, las shown in FIGURE 5, normal to the axis ott the push rod 52 and in retaining engagement with the upper surface of the ange 62 of the band titl, whereby the push rod 52, and hence the lead 34, are maintained in extended position, against the resistance of the spring 42. The inner end of the detent 124 is laterally outwardly and upwardly angled, ias indicated at 130, so that, when the catch 112 is operated to its release position, thedetent 124 can clear the main push rod portion 54, as shown in FIGURE 3, iso as to enable the spring 42 to retract the push rod 52, Iand hence the lead 3d into the pencil tip 26, as shown in FIGURE 3. The angled end 130 of the detent 124 Vthen rides upon the `outer surface of the main push rod portion 54, until and unless the push rod is pushed downwardly to extend the lead 34 to use position. Y

'Ilhecatch 112 is biased toward its engaged position by means of a longitudinally elongated leaf spring 132, which is outwardly bowed away from the barrel 10. The spring 132 has a return bent terminal 134, on its lower end, which is located retainably within the tip 110 of the pocket clip arm 104, and its main portion 136 bears outwardly against the web 108er the pocket clip `arm 164. `The upper end of the spring 132 has an out-turned terminal 138 thereon, which bears against a concavely curved outer edge portion 140 of the linger piece 114, between the fulcrum 116 and the `detent 124, whereby the ldetent 124 is urged inwardly through the slot 126. 'It will be understood from the foregoing that extension of Iand locking of the lead 34 to its use position, shown in FIGURE 5, fromthe retracted position shown in FIG- URE 3, requires only a downward push on lthe push rod knobV 56, and that retraction of the lead to its protected position` within the pencil tip 26, requires only inward pressure upon the exposed upper .portion of the catch finger piece 114; and that downward rfeeding of the lead 34, relatives to the lead holder 36, requires only rotation of the push rod 52, in the proper direction by means of the knob 56.

Although there has been shown and described herein a preferred lform of the invention, it is to be understood that the invention is not necessarily confined thereto, and

that any change or changes in the structure of andin die relative arrangements of components thereof are contemplated as being within the scope of the invention `as defined lby the claims appended hereto.

What is claimed is:

1. A mechanical pencil comprising a tubular barrel having lower [and upper ends, said barrel having la main axial bore extending to said lower end and a reduced diameter axial bore extending from said upper end to the main bore, a tubular tip threaded into the lower end of the main bore, said tip having an axial bore smaller in diameter than said main bore, a tubular split spring lead holder sliding in the tip bore and having ya lateral annular :Flange on its upper end, a coil spring circumposed on the lead Vholder and compressed between said lateral langeand the tip, la pusher block engaged non-rotatably and slidably in the main barrel bore and engaged with the upper end of the Ilead holder, ya push rod engaged slidably androtatably in the mainbarrel bore, `a feeding and retracting screw supported within said push rod and threaded through said pusher block, said push rod having a reduced diameter knob on its upper end extending through said reduced diameter barrel bore and reaching beyond the upper end of the barrel, the upper end of main portion ofthe push rod :and said knob defining a shoulder, and laterally inwardly `spring-pressed catch means ladapted to engage behind said shoulder in 'a downwardly extended position of the push rodl wherein a lead `engaged in the lead holder is extended fout of the tip to use position.`

2. A mechanical'pencil comprising a tubular barrel having lower and upper ends, said barrel having a main axial bore extending to said lower end andV a reduced diameter axial bore extending yfrom said upper end to the main bore, a tubular tip threaded into the lower end of the main bore,-said tip having an axial bore smaller in diameter than said main bore, a tubular split spring lead holder sliding in the tip bore and having a lateral annular lange 4on its upper end, a coil spring circumposed lon the lead holder and compressed between said lateral flange and Vthe tip, a pusher block engaged non-rotatably and slidably in the main barrel bore and engaged with the upper end of the lead holder, a push rod engaged slidably and rotatably in the main barrel bore, a feeding and retracting screw supported within said push rod and threaded through said pusher block, said push rod having a reduced `diameter knob on its upper end extending through said reduced diameter barrel bore and reaching beyond the upper end of the barrel, the upper end of main portion of the push rod and said knob defining a shoulder, and laterally inwardly spring-pressed catch means adapted to engage behind said shoulder in a downwardly extended position of the push rod wherein a lead engaged in the lead holder is extended out lof the tip to use position, said catch means being releasable from the shoulder to enable the spring to retract the push rod and retract a lead in the lead holder into the tip.

3. A mechanical pencil comprising `a tubular barrel having lower and upper ends, said barrel having a main axial bore extending to said lower end and a reduced diameter Vaxial bore extending from said upper end to the mainhore, a tubular tip threaded in to the lower end ci the main bore, said tip having an axial bore smaller in diameter than said main bore, a tubular split spring lead holder sliding in the tip bore .and having a lateral annular llange on its upper end, la coil spring circumposed lon the lead holder and compressed between said lateral llange andthe tip, a pusher block engaged non-rotatably and slidably in the main barrel bore and engaged with the upper end of the lead holder, a push rod engaged slidably androtatably in the main barrel bore, said push rod having a reduced diameter knob 'on its upper end extending through said reduced diameter barrel bore and reaching beyond the upper end of the barrel, the upper end of main portion of the push rod and said knob delining a shoulder,

and laterally inwardly spring-pressed catch means adapted to engage behind said shoulder in a downwardly extended position oi the push rod wherein a lead engaged in the lead holder is extended out of the tip to use position, said catch means lbeing releasable from the shoulder to enable the spring to retract the push rod and retract ya lead in the lead holder into the tip, said main push rod portion having an axial blind bore opening to its lower end, said bore being non-cylindrical, a lead feeding screw engaged in said blind bore, said screw being non-cylindrical `and #being slidably and non-rotatably engaged in lche blind bore, said pusher block having a threaded axial bore through which the screw is threaded, the screw having `a :lower end engageable with the upper end of a lead engaged in said lead holder.

4. A mechanical pencil comprising a tubular barrel having llower and upper ends, said barrel having a main Vaxial bore extending to said lower end and a reduced diameter axial bore extending from said upper end to the main bore, a tubular tip threaded into the lower end lof the main bore, said tip having an axial bore smaller in diameter than said main bore, la tubular split spring lead holder sliding in the tip bore and having a lateral annular ange lon its upper end, la coil spring circumposed `on the [lead holder and compressed between said lateral ange and the tip, a pusher block engaged non-rotatably land slidably in the main barrel bore and engaged with the upper end of the lead holder, a push rod engaged slidably and rotatably in the main Ibarrel bore, said push rod having a reduced diameter knob yon its upper end extending through said reduced diameter barrel bore and reaching ibeyond the upper end of the barrel, the upper end `of main portion of the push rod and said knob defining a shoulder, and laterally inwardly springapressed catch means adapted to engage behind said shoulder in a downwardly extended position orf the pfush rod wherein a lead engaged in the lead holder is extended `out of the tip to use position, said catch means being a component of a pocket clip and catch assembly mounted on the exterior of the barrel adjacent to the upper end of the barrel, said assembly comprising la pocket clip having a channel upper portion secured to the barrel and a pocket clip arm extending downwardly from said upper portion, said upper portion having side walls and a web, said web being spaced from the `barrel and having Ia longitudinal slot therein, a catch comprising a longitudinally elongated finger extending through the web slot land having a lower end portion within said upper portion and an upper end portion extending above said upper portion, said finger piece having a downwardly extending fulcrum lug intermediate its ends, a depression in the barrel in which said lug is seated, and a laterally inwardly extending detent on the lower end of the linger piece, the sidewall of the barrel having opening means through which the detent enters the main barrel bore and engages behind said shoulder, and spring means compressed between the web of the upper portion of the clip and the linger piece. p

5. A mechanical pencil comprising a tubular barrel having lower and .upper ends, said barrel having a main axial bore extending to said lower lend and a reduced diameter axial boire extending from said upper end to the main bore, a tubular tip threaded into the lower end of the main bore, said tip having an axial bore smaller in `diameter than said main bore, a tubular split spring lead holder sliding in the tip bore and having a lateral annular ilange on its upper end, a coil spring circumposed on the lead holder and compressed between said lateral flange and the tip, `a pusher block engaged nonrotatably and slidably in the anain barrel bore and engagcd with the upper end ot" the lead holder, a push rod engaged slidably and rotatably in the main barrel bore, said push rod having a reduced diameter knob on its upper `end extending through said reduced diameter barrel bore and reaching beyond the upper end of the barrel, the upper end of the main portion of the push rod and said knob denin-g a shonlder, and laterally inwardly spring-pressed catch means adapted to engage behind said shoulder in a downwardly extended position of the push rod wherein a lead engaged in the lead holder is extended :ont off the tip to ruse position, said catch means being a component of a pocket clip and catch assembly mounted ion the exterior of the barrel adjacent to the :upper end of the barrel, said assembly comprising a pocket clip having a channel upper portion secure-d to the barrel and a pocket clip arm extending downwardly =irom said upper portion, said upper portion having side walls and a web, said web being spaced from the barrel and having a longitudinal slot therein, a catch compising a longitudinally elongated finger piece extending through the web slot and having a lower end portion within said upper portion and an upper end portion extending above said npper portion, said linger piece having a `downwardly extending fnlorum lug intermediate its ends, a [depression in the barrel in which said lug is seated, and a late-rally inwardly extending detent on the lower end of |the linger piece, the sidewall of the banrel having `opening, means through which the detent `enters the main barrel bore and engages behind said shonlder, and spring means compressed between the web of the rupper portion of the clip and the linger piece, said spring means comprising a longitudinally elongated outwardly bowed leaf spring having a lower end secured to the pocket clip arm, an intermediate portion bearing against the laterally inward side of said clip arm, and an upper end bearing npon the laterally Koutward edge of the nger piece in the region of the detent.

References Cited in the tile of this patent UNITED STATES PATENTS 1,583,718 Hndson May 4, 1926 2,811,945 Keller Nov. 5, 1957 FOREIGN PATENTS 964,025 France Jan. 18, 1950 286,888 Switzerland Mar. 2, 1953 1,125,062 France July 9, 1956

Claims

1. A MECHANICAL PENCIL COMPRISING A TUBULAR BARREL HAVING LOWER AND UPPER ENDS, SAID BARREL HAVING A MAIN AXIAL BORE EXTENDING TO SAID LOWER END AND A REDUCED DIAMETER AXIAL BORE EXTENDING FROM SAID UPPER END TO THE MAIN BORE, A TUBULAR TIP THREADED INTO THE LOWER END OF THE MAIN BORE, SAID TIP HAVING AN AXIAL BORE SMALLER IN DIAMETER THAN SAID MAIN BORE, A TUBULAR SPLIT SPRING LEAD HOLDER SLIDING IN THE TIP BORE AND HAVING A LATERAL ANNULAR FLANGE ON ITS UPPER END, A COIL SPRING CIRCUMPOSED ON THE LEAD HOLDER AND COMPRESSED BETWEEN SAID LATERAL FLANGE AND THE TIP, A PUSHER BLOCK ENGAGED NON-ROTATABLY AND SLIDABLY IN THE MAIN BARREL BORE AND ENGAGED WITH THE UPPER END OF THE LEAD HOLDER, A PUSH ROD ENGAGED SLIDABLY AND ROTATABLY IN THE MAIN BARREL BORE, A FEEDING AND RETRACTING SCREW SUPPORTED WITHIN SAID PUSH ROD AND THREADED THROUGH SAID PUSHER BLOCK, SAID PUSH ROD HAVING A REDUCED DIAMETER KNOB ON ITS UPPER END EXTENDING THROUGH SAID REDUCED DIAMETER BARREL BORE AND REACHING BEYOND THE UPPER END OF THE BARREL, THE UPPER END OF MAIN PORTION OF THE PUSH ROD AND SAID KNOB DEFINING A SHOULDER, AND LATERALLY INWARDLY SPRING-PRESSED CATCH MEANS ADAPTED TO ENGAGE BEHIND SAID SHOULDER IN A DOWNWARDLY EXTENDED POSITION OF THE PUSH ROD WHEREIN A LEAD ENGAGED IN THE LEAD HOLDER IS EXTENDED OUT OF THE TIP TO USE POSITION.