US2030025A - Mechanical pencil - Google Patents

Description

C. H. DAVIS Feb, 4, 1936.

PENCIL Filed March 15, 1954 MECHANI CAL INVENTOR.

ATTORNEY.

Patented Feb. 4, 1936 UNITED STATES PATENT OFFICE 25 Claims.

The present invention pertains to a novel automatic or mechanical pencil that has certain objects in common with the pencil shown and described in my earlier application, Serial No.

339,507, filed February 13, 1929.

Ordinarily a mechanical pencil embodies feed ing mechanism consisting of a tube having a spiral slot and a longitudinally slotted channel tube in concentric relation, a lead carrier within these :parts, and an expelling pin within the carrier. Fingers project from the carrier and pin through the slot in the channel tube and into the spiral slot in the other tube. Rotation of one of the tubes imparts a lengthwise motion to the carrier ";and expelling pin. At the forward end of the movement, the forward end of the expelling pin passes out of the carrier and thereby expels the last fragment of the consumed lead. A mechanical pencil is also usually formed with a chamber ;.or magazine for lead, and in order to obtain access thereto, it is often necessary to detach a part of the pencil assembly. Some inconvenience is experienced in replacing this part while holding the new lead or laying it aside, for the magazine 251=must be closed to avoid spilling the leads while manipulating the pencil in refilling.

To permit insertion of the new lead, it is necessary to operate the pencil manually in the reverse direction to retract the expelling pin into '1the carrier member. With the lead initially inserted in the carrier, the pencil must be operated to withdraw the lead into the pencil until only the forward point thereof is exposed. The principal objects of this invention are to eliminate Ethe inconveniences of removing a lead in the conventional manner described and of operating the pencil manually in order to insert the new lead.

The first of these objects is accomplished by a 401novel construction of the magazine whereby a lead is delivered or made accessible by sliding one of the pencil casing sections outwardly relative to the other rather than removing a part entirely from the assembly. An outward pull on athe shiftable or relatively movable body section exposes a groove formed in the operating tube on which the section is mounted. This groove is in communication with the magazine and is so positioned that it readily receives a lead from the .magazine. Suitable finger dents are provided at the sides of the groove in order to facilitate taking hold of the lead therein.

'I'he second main object is accomplished by constructing the feed mechanism in such a way .that it is readily reversible by pressure of the.

new lead on the exposed end of the expelling pin, Without manual rotation or operation of the feeding mechanism. The conventional feeding mechanism described above requires ordinarily that the two tubes be attached respectively to the relatively rotatable parts of the pencil body. So long as these connections are maintained, the mechanism can be operated in reverse direction only by turning one of the body sections. According to the present invention, however, the connection of one of the body sections to the corresponding tube is broken on extending the pencil to uncover the lead supply groove. The broken connection leaves one of the tubes free, and reverse action may then be eifected by mere pressure on the'forward end of the exposed pin by the new lead.

Further, the feeding mechanism is so constructed that initial pressure on the expelling pin moves the pin into the pencil body and then relatively inward of the carrier member, whereby the latter may engage the lead. After the lead has thus been engaged in the carrier, both the pin and the carrier move at the same rate inward of the pencil body. The new lead is inserted as far as desired, and the pencil body is then contracted to cover the lead delivery slot and to reestablish the driving connection which was previously broken.

. The invention is fully described by way of an example in the following description and in the accompanying drawing in which:

Figure 1- is an elevation of the device;

Figure 2 is a longitudinal section;

Figure 3 is an elevation of the device, partly in section, in pulled out condition for delivery of a new lead;

Figures 4 and 5 are sections on the lines 4-4 and 5--5 respectively of Figures 2 and 3;

Figure 6 is a section on the line 66 on Figure 2, and

Figure 7 is a detail elevation of the forward end of the spiral.

Reference to these views will now be made by use of like characters which are employed to designate corresponding parts throughout.

The device may be regarded as assembled on and in an operating tube l on which are mounted three casing sections namely, an upper section 2, an intermediate section 3 and a lower section 4, the latter having a tapering lower end 5. The upper section 2 is slidable on the tube I so that it may be removed to expose the eraser I held in the upper end of the tube I. The section 2 may have a liner 6 if desired, Also, on removal of the eraser, leads 8 may be dropped into the operating tube which functions as a magazine, as will presently be described.

The intermediate section 3 is fixed firmly on the tube I so that the latter may be pulled outwardly with respect to the lower section 4 as will presently appear. To facilitate such relative sliding movement, the section 4 is spaced from the operating tube at 9, but the parts are nevertheless maintainedin rotatable relation by means of a bushing or bearing |0. inserted between them at the upper end of the section.

The feed mechanism is for the most part con-: ventional, consisting of a spiral tube II and a channel tube |2 mounted one within the other in the axis of the pencil. In this case the channel tube is within the spiral and projects into the tapered end 5 where it receives a tip |& screwed thereon at M whereby the channel tube is held in fixed position. A spacer 5 is inserted in the end 5 behind the tip I13, andthespi-ral tube. rests: thereon as may beseen in: Figure 2;. The-lower end of the spiral tube is surrounded by a clutch member lfi securely fixed thereon and consisting of a serrated. orcorrugated ring. as may be. seen more clearly in. Figures. 3 andiz'l. Thelower end of the operating. tube isreducedin diameter and also serrated. or corrugated, as indicated bythe: numeral l T, toserve asaa complementary clutch=mem-- her, and isadapted to slide on and off the memher [6. Thus, on pulling the. operating tube outwardly by means. of. the intermediate section. 3, the driving connection between-the operating tube and the spiral tube is broken, as illustrated in Figure 3.

The channelitubeslidably receives a lead carrier in the form of a split tube l8 adapted: to hold a lead 19: in its lower end by friction, such. lead passing through the. tip B in the usual manner; The carrier t8 is formed with afinger; 20: extending into the groove. 2| of thespiral tube: afterpassing through the s1ot.|2! of. the channel tube 2. The carrier tube, inturn, receives a. slidable expelling pin 22 bearing againstzthe rear end of the lead |9- and having itsrear end; formed asafinger 23 to pass through the slot IE2 and into the. groove of the spiral ata point behind the finger 2E The upper end of the channel tube is flanged outward at 2.16., and beneath the flange a washer 25 is fixedion the channel. tube. Thiswasheris of such size as to. be engaged bythe reducecl por tion I? of the. operating tube I when: the latter is drawn outwardly as illustrated in Figurev 3. Between. the washer 25zand: the upper end of; the spiral tube is mounted afree or rotatable washer 26 for a purpose which will presently appear.

The lower part'of: the operating tube is formed with a lengthwise groove 21 of. slightlyless-length than astandard lead. When theparts arexinthe working position shown in Figure 2, the upper end of thisgroove is disposed at orslig-htly below; the lower end of the intermediate section.3'.. Finally a block 28 with an inclined upper: face 2'9Lris held by a press fit in the operating tubeat the upper end of the. groove 21. The groove aidsinsecuring theblock in. the tube, and it. will be. seen in Figure 2 thatv the upper face of the bloclc con-- stitutes the bottom of. the lead magazine pro.- vided. in the upper part of. the. operating tubebeneath the eraser. 1..

In the use of the deviceiasithusfar described one.

of the leads. Swill gravitateinto the groove 2156.111-

ing the ordinary manipulation of. thepenci'l'l. In. order to make this lead. accessible for'reefill put-1 poses, the operating tube is pulled outwardly by a pull on the section 3 so that the parts assume the position shown in Figure 3 wherein the groove 21 and lead therein are exposed, except for the upper extremity 3| thereof to prevent the lead from falling out. The lead may be gripped at finger dents 32 formed at opposite sides of the groove 21, as shown in Figures 3 and 5. As a result of this outward movement of the operating tube the clutch. I6, I! is released as shown in Figure 3, and the outward movement of the operating tube I is limited by the engagement of the reduced portion I! with the washer 25, the latter in turn being stopped against the flange 24 of the anchored channel tube |2. The intermediate section 3' carries an. indicator 33 placed in line with the groove 21, so that the user may have the groove uppermost when pulling the operating tube outward.

The spiral groove 2| terminates at its forward end.- in. a. circumferential portion. forming: a shoulder 3:4; disposed at zero pitch transversely ofth'e axis of the pencil. This portion terminates in. a stop. or. shoulder 35. Directly behind the. shoulder 34, the width of the. spiral groove is increased as indicated by the; numeraldt. in Figures 3 and 7.. The widening is accomplished. by cutting. away theupper edge of the-groove through an extent of about 130. around the spiraltube; from the shoulder 34, as indicated by. the numeral 31, thereby also. reducing the pitch. of the spiral where cut.

The. normal distance between convolutions of the spiral: groove 2! is such that the. forward end. of the expelling pin 22. is within the. carrier tube 2. so that: the rear end of the. lead l9. may

bereceived in the carrier in the usual manner as. shown: in Figure 2.. This relation is maintained as.

the lead |9Jis fed out until the pin. 25! reaches the shoulder 34. From this point on,.the. carrier'tube does. not go' forward, but the expelling pin con.-

tinues itsforward movement. so. that. its forward end passesbeyondv the forwardend of thecarrier tube, thereby expelling. the remaining. fragment of lead in. the. usual manner; At this time, the.

pirr 22whereuponthe latter moves rearward and the free spiral tube rotates inasmuch as: the pin 23 is in the spiral part of the groove 2|, and the cha-nneli tube. I2 is: anchored. The loose. washer 2E facilitates. rotation of thespiral tube: in case this washer is pushed into. engagement. with the larger washer 25.. There is no similar backward movement of the carrier tube as long asits finger 20. rides; along the square shoulder 34.v The length of the. shoulder 34 is such as to. permit the forward end of the pin 22. to come flush with the forward end; of the carrier tube by the time the pin passes from the shoulder 34 into the widened groove 36 at the reduced pitch: shoulder 37.,

This shoulder permits the carrier tube to. begin moving rearward and at; the same time causes further relative movement between the expelling pin and the carrier tubeuntil both fingers 2B and 23 have entered the uniformly spaced partsof the By this time, as a result of this.

spirallgroove. 2|.

relative movement the carrier tube l8 has been pushed over the forward end of the expelling pin 22 and over the rear end of the newly inserted lead. This action is inherent in the spacing of the convolutions of groove 2| with relation to the expelling pin and carrier tube.

The widening of the spiral groove at 36 plays no part in the loading operation, but the difference in pitch causes the overlapping of the carrier tube [8 on pin 22 as already set forth. The reverse of this overlapping action is not desired, however, on the feeding movement before carrier finger 20 has reached spacer IS. The widened groove is therefore provided in order to permit, on the feeding movement, a free movement of finger 20 so that tube l8 and pin 22 travel at the same speed by propulsion at finger 23 and the frictional connection between the lead and the carrier tube, with no expelling of the lead until finger 20' bears on spacer l5. It will thus be seen that while on the loading operation finger 20 is guided by the reduced pitch shoulder 31, it is guided on the feeding operation by spacer It may now be seen that a new lead is readily delivered from the magazine Without disassembling any part of the pencil structure and without danger of spilling the leads remaining in the magazine. It is also to be noted that the pulling of the upper section 2 outwardly to expose the lead .delivery groove also conditions the feeding mechanism for the free reverse action by the pressure of the lead inwardly on the forward end of the expelling pin 22. Finally, the return of the section 2 to its normal position causes the operating tube I to be connected. again to the spiral tube H at the clutch I6, l7. The operating tube, in turn, may be rotated, in the normal operation of the device, by turning either section 2 or 3, there being sufiicient friction between the operating tube and the section 2 to enable actuation by turning the member 2.

Although a specific embodiment of the invention has been illustrated and described, it will be understood that various alterations in the details of construction may be made without departing from the scope of the invention, as indicated by the appended claims.

What I claim is:

1. A pencil having two relatively rotatable and axially shiftable body sections and feeding mechanism including two relatively rotatable parts one within the other and attached respectively to said body sections and operable by rotation of one of the body sections, and a slidable feed member within said parts and propelled thereby on relative rotation of said body sections in one direction, one of said body sections being readily detachable from the corresponding mechanism part on relative axial shifting of one of said body sections, whereby said mechanism parts become freely movable relatively to each other in the reverse direction by axial inward pressure on said feed member.

2. A pencil comprising upper and lower casing sections rotatably and slidably mounted relatively to the other, a lead chamber formed within the upper section and having a delivery groove rendered accessible on sliding said sections apart, feeding mechanism including two relatively rotatable parts one within the other and attached respectively to said body sections and operable by rotation of one of the body sections, and a slidable feed member within said parts and propelled thereby on relative rotation of said body sections in one direction, one of said body sections being readily detachable from the corresponding mechanism part on relative axial shifting of one of said body sections, whereby said mechanism parts become freely movable relatively to each other in the reverse direction by axial inward pressure on said feed member.

3. A pencil comprising an operating tube, upper and lower casing sections mounted thereon, the upper section being rotatable and slidable relatively to the lower section, feeding mechanism comprising two relatively rotatable parts, one within the other and attached respectively to said operating tube and lower casing section, and a slidable feed member within said parts and propelled thereby on relative rotation of said casing sections in one direction, the operating tube being detachable from the corresponding mechanism part on sliding said casing sections apart, whereby said mechanism parts become freely movable relatively to each other in the reverse direction by axial inward pressure on said feed member.

4. A pencil comprising an operating tube, upper and lower casing sections mounted thereon, the upper section being rotatable and slidable relatively to the lower section, feeding mechanism comprising two relatively rotatable parts, one within the other and attached respectively to said operating tube and lower casing section, a slidable feed member within said parts and propelled thereby on relative rotation of said casing sections in one direction, the operating tube being detachable from the corresponding mechanism part on sliding said casing sections apart, whereby said mechanism parts become freely movable relatively to each other in the reverse direction by axial inward pressure on said feed member, the upper portion of said operating tube being adapted as a magazine for leads, and lead-delivery means below said magazine portion and. exposed on sliding said sections apart.

5. A pencil comprising an operating tube, upper and lower casing sections mounted thereon, the upper section being rotatable and slidable relatively to the lower section, feeding mechanism comprising two relatively rotatable parts, one within the other and attached respectively to said operating tube and lower casing section, a slidable feed member within said parts and propelled thereby on relative rotation of said casing sections in one direction, the operating tube being detachable from the corresponding mechanism part on sliding said casing sections apart, whereby said mechanism parts become freely movable relatively to each other in the reverse direction by axial inward pressure on said feed member, the upper portion of said operating tube being adapted as a magazine for leads, said tube being formed with a lead-receiving groove below said magazine and in communication therewith, said groove being exposed on sliding said sections apart.

6. A pencil comprising an operating tube, upper and lower casing sections mounted thereon, the upper section being rotatable and slidable relatively to the lower section, feeding mechanism comprising two relatively rotatable parts, one within the other and attached respectively to said operating tube and lower casing section, a slidable feed member within said parts and propelled thereby on relative rotation of said casing sections in one direction, the operating tube being detachable from the corresponding mechanism part on sliding said casing sections apart, whereby said mechanism parts become freely movable relatively to each other inthe reverse direction. by

axial inward. pressure on. said feedmembentthe. upper portion. of" said operating tubezbeing adapted as a magazine for. leads, saidtube being formed with a lead-receiving groovebelowsaid magazine and in communication therewith,.said groove. be.- ing exposed on sliding said sections apart, and an inclined bottom. piece. in said magazine and sloping downwardly toward saidgroove;

7. A pencil comprising an operating. tube, upper. and. lower casing. sections on said tube, thelozwer scetion being rotatable and slidable onsaid tube,.

the upper. section. being. movable with said tube. and relatively to thelowersection, feeding mechanism. in said tube including two relatively rd;- tatable parts one within the other and attached; respectively to said lower section and. tube, and a slidable feed member within said. parts and propelled thereby on relative rotation. of; said. casing sections in. one direction, the operatingtube; being detachable. from the. corresponding mechanism part on sliding. of said sections apart',,wher.e=- by said mechanism parts become freely movable relatively to each other in thereversedirectionby axial inward. pressure on said feed member;

8. A pencil. comprising an operating tube, upper and lower casing sections. on said tube, the lower section being rotatable and slidable on said tube, the upper. section being movable with said tube and relatively to the lower section, feeding mechanism in said tube including two relatively rotatable parts one within the other and attached respectively to said lower section and tube,.a slidable feed member within said parts and propelled. thereby on relative rotation of said. casing sections in one direction, the operating tube being detachable from the corresponding mechanism.

part on sliding of said sections apart, whereby said mechanism parts become freely movablerelatively to each. other in the reverse direction. by axial inward pressure on said feed member, the upper portion of said operating tube being adapted as a magazine for leads, and. lead-delivery means below said magazine portion. and exposed on sliding said sections. apart.

9. A pencil comprising an operating. tube, upper and lower casing. sections mounted thereon, the upper section being rotatable and slidable relatively to the lower section, the feeding mechanism including. a spirally grooved tube and a channel tube one within the other and attached. respectively to said operating tube and lower casing section, the operating tube being detach-- able from the corresponding mechanism tubeon pulling: said sections apart, a slidable carrier member within. said tubes'and having a finger'passing laterally through said tubes, and a slidable expelling pin in said carrier member, adapted to pass forwardly therethrough and having. a finger extending laterally through said tubes, the forward portion of the spiral groove having a reduced pitch angle adapted to receive the finger of said carrier member to reduce the axial speed of said carrier member relatively to said pin.

10; A pencil comprising an operating tube, upper and lower casing. sections mounted thereon, the upper section being rotatable and slidable relatively to the lower section, and feeding mechanism including a spirally grooved; tube and achannel tube one within the other and. attached respectively to said operating tube and lower casing section, the operating tube being detachable from the corresponding mechanism tube-on pulling said sections apart, a slidable carrier member within said tubes and having a finger. passing c ances? laterally through. said. tubes; and a; slidable expelling: pin; in said. carrier member, adapted to pass'forwardly therethrough and having a finger extending laterally through said tubes, the forwardportion. of. the: spiral groove having a reduced pitch angle adapted. to receive the finger of said carrier member to reduce the axial speed of said carrier member relatively to said pin; the upper portion of said operating tube being adapted as a magazine'for leads, and lead-delivery means below; said'magazineportion and exposed on sliding" said sections: apart..

1 1. Apencil comprising an operating tube, upper and. lower casing sections: mounted thereon, the upper section being. slidable. relatively to the lower section,.the upper portion of said operating tubebeing adapted to contain leads, and leaddelivery means formed in said operating tube below and in communication withsaid portion and" exposed on sliding said sections apart.

12; A pencil comp-rising an operating tube, upper and lower casing sections mounted thereon, the upper section-being slidable relatively to the lower section, theupper portion. of said. operating tube being adapted to contain leads, said tube beingformed with a lead-receiving groove below said portion and in. communication: therewith, said groove being exposed onsli'ding said sections apart.

13. In apencil' of the class described, a tubular member having a groove, mechanismengageable with a leadincluding a follower member extending within said groove and movable lengthwise within said tubul'armember', plunger means connected with said follower member being movable vvithin the tubular member" in response to the engagement therewith of one end of an inserted lea-d, without necessitating. the disengagementof the follower member from the. groove, and a. second. tubular member having a groove for receiving said follower member; and cooperating with. the other: tubular member to guide the follower member.

14.. In a pencil of the class described, a tubular member having a spiral groove, a follower means for longitudinally actuating a lead and having a portion forengagement with a lead, said follower meansincluding. a follower member extending within the spiral groove and plunger means connected therewith and adapted to be moved lengthwise within the pencil in response to relative. rotative movement between the follower member and the tubular member, said follower means being. movable inwardly within the casing inre'sponse to the engagement therewith by an inserted'j lead without disengaging said follower member from the spiral groove, and a second tubular member having a longitudinal groove for receiving; said follower member and cooperating with the other tubular member to produce said relative rotative movement.

15. In a pencil of the class described, a pair of relatively rotatable tubular members, one of said members within the other, one of said members being provided with a spiral groove, and the other a longitudinal groove, a follower member for longitudinally' shifting a lead; said follower mem ber extending into the grooves and adapted in response to relative rotation between said tubular members to be recip-rocated' longitudinally thereof, and shiftable meansoperable in one position for securing one of said tubular members in fixed position with. respect to the. tip" of the pencil structure, and when. in another shifted position for releasing said tubular member.

16; Ina pencil: of the class described, a pair of relatively movable tubular members, one of said members within the other, one of said members being provided with a spiral groove, and the other a longitudinal groove, a follower member for longitudinally shifting a lead, said follower member extending into the grooves and adapted to be longitudinally reciprocated in response to relative movement between said tubular member, and shiftable means operable in one position for securing one of said tubular members in a fixed position with respect to the tip of the pencil structure.

17. In a pencil of the class described, a pair of relatively rotatable tubular members, one of said members within the other, one of said members being provided with a spiral groove, and the other a longitudinal groove, a lead actuating follower member extending within said grooves and adapted to be reciprocated longitudinally of the tubular members in response to relative movement thereof, and shiftable means operable when in one position for securing one of said tubular members in a fixed position against rotation with respect to the tip of the pencil structure, and when in another shifted position for releasing said tubular member, said locking and releasing means being operable at any stage of the operation of the follower member.

18. In a pencil of the class described, a pair of tubular members, one of said members being rotatable within the other member and provided with a spiral groove, the other member having a longitudinal groove provided therein, a lead actuating follower member extending within said groves and adapted, when a lead is inserted through the tip of the pencil, to cause rotation of the spirally grooved tubular member and thereby effect displacement of said follower member longitudinally of said tubular members to an alternate position within the pencil, and locking means for securing said spirally grooved tubular member against rotation with respect to the tip of the pencil structure, whereby to permit of forward longitudinal movement of the lead actuating member.

19. In a pencil of the class described, a pair of relatively rotatable tubular members, one of said members being inside of the other, a cap, oneof said tubular members being connected at one end of the pencil with said cap, the other member being adapted to be secured at the opposite end of the pencil, one of said members being provided with a spiral groove, and the other a longitudinal groove, a lead actuating follower member within one of said tubular members having a section extending into said spiral groove, and means for locking one of said tubular members against rotation with respect to the top of the pencil structure to thereby effect the forward movement of the lead actuating follower member in response to rotation of the other member and for releasing said first mentioned tubular member, whereby said follower member may be pushed back within the pencil by engaging the same with the end of an inserted lead to thereby effect the refilling of the pencil.

20. A pencil of the class described, a pair of relatively rotatable tubular members, one member being within the other, a cap connected with one of said members for effecting rotation thereof, one of said members being provided with a spiral groove and the other with a longitudinal groove, a lead actuating follower member positioned within said tubular members and projecting within said grooves, whereby said member may be reciprocated within the tubular members in response to relative rotation of said members, the forward movement of the follower member being occasioned in response to rotation of the cap, and means for securing oneof the tubular members against rotation with respect to the tip of the pencil structure whereby relative rotation between the tubular members may beeffected in responsetothe rotation ofv said cap, said means being releasable to render the follower member capable of being pushed back within the pencil Without rotation of said cap.

21. In a pencil of the class described, a pair of tubular members, one of said members being provided with a spiral groove and the other with a longitudinal groove, a cap fixed to one of said tubular members for imparting rotation thereto, a lead carrier associated with said spiral and longitudinal grooves and positioned within one of said tubular members, whereby relative rotation between said tubular members will cause longitudinal movement of the carrier, and means positioned at one end of the pencil for securing one of the tubular members against rotation with respect to the tip of the pencil structure whereby forward movement of the lead carrier may be obtained in response to rotation of the cap, said means being adapted to be released so that the lead carrier may be readily pushed back to a shifted position.

22. In a pencil of the class described, a tubular member having a longitudinal slot, a cap secured to said tubular member, a second tubular member having a spiral groove, a lead actuating follower member extending within said longitudinal and spiral grooves and positioned within one of said tubular members, and means for securing said spirally grooved tubular member against rotation, with respect to the tip of the pencil structure while the lead actuating member is being moved in one direction, said means being releasable, whereby the follower member may be retracted for the purpose of refilling.

23. In a pencil of the class described, a tubular member having a longitudinal groove, a cap secured to said tubular member, a second tubular member having a spiral groove, a lead actuating follower member extending within said spiral and longitudinal grooves and positioned within one of said tubular members and adapted, in response to relative rotation between said tubular members, to be longitudinally reciprocated, the forward movement of the follower member being occasioned in response to rotation imparted to the cap, and shiftable means operable when in one position for securing the spirally grooved tubular member against rotation with respect to the tip of the pencil structure, said means being operable when in another shifted position for releasing said tubular member.

24. In a pencil of the class described, a pair of relatively rotatable tubular members, one of said members being positioned inside of the other, each of said members being provided with a groove, a follower member for engaging a lead, a portion of said follower member extending within the grooves of said tubular members and adapted, in response to relative rotation between said tubular members to be reciprocated longitudinally thereof, a cap operatively connected to one of said members, and means for securing or releasing one of the tubular members with respect to the tip of the pencil structure so as to enable free rotation of said member relative to the other tubular member when the tollower member is pushed back within the pencil.

25. A pencil having two relatively rotatable and axially shiftable casing sections and feeding mechanism including a spirally grooved tube and a channel tube one within the other-and attached respectively to. said casing sections and operable by rotation of one of said sections, aslidable carrier member within said tubes and having a fin- 10 ger passing laterally through the grooves in said tubes, and a slidable expelling pinin said carrier member, adapted to pass forwardly therethrough and having a finger extending laterally through said grooves, the forward portion of the spiral groove being widened to permit a free movement of the carrier finger and carrier to their extreme forward position before said pin begins to pass forwardly through said carrier member.

CY H. DAVIS.

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