US2469411A - Mechanical pencil - Google Patents

Description

2 Sheets-Sheet 1 Filed NOV. 13, 1945 www@ May 10, 1949 J. J. RoBBlNs 2,469,411

MECHANICAL PENCIL Filed NOV. l5, 1945 2 Sheets-Sheet 2 Patented May 10, 1949 MECHANICAL PENCIL Jesse J. Robbins, Glendale, Calif., assignor to Stylofede Corporation, Glendale, Calif., a corporation of California `Application November 13, 1945, Serial No. 628,063

17 Claims. 1

My invention relates rto :pencils and more particularly t-o the mechanical type of pencil whereby when the lead is broken or used np, it can be replaced, and when worn can be extended to provide a satisfactory'writing point.

I-Ieretofore7 in a mechanica-l pencil of the usual type wherein thelead point has been worn down, to provide a fresh writing point it is necessary to remove the pencil from the writingposition, turn in some manner a portion of the pencil with the non-writing hand and .return the said pencil to a writing position. Moreover, when the lead of such a pencil has been used up, it has eeen found necessary to disassemble the said pencil, retrieving anew piece of lead from the storage place in the said pencil, set the said lead into the end ofthe pencil .and readjust the lead to provide a new writing point. It is apparent that in the above operations, considerable loss of time is occasioned in addition to the dirtying of the hands, the possible dropping of the lead in the filling operation and the diiiiculties attendant upon proper insertion of the lead into a cooperating position within the pencil.

My object in this invention is to provide a mechanical pencil obviating the above difliculties by iirst incorporating a feed mechanism within the pencil which enables the writer to refresh the lead point of the pencil by the mere expedient of pressing the pencil point upon the writing surface, said pressing being competent to cause an extending of the lead from the pencil to provide a writing point, and second, constructing my pencil so that upon the using up of the piece of lead being .used for Writing, an automatic gravity feeding of the lead is accomplished whereby lead moveslgravitationally from the storage compartment of the pencil into the feed mechanism of the pencil and .is thereby positioned for extension to provide a writing point in the manner .previously described.

Previous to-this time, I have devised a pencil providing an automatic feed of leadfrom a storage compartment to-a feeding mechanism `and have provided the said feeding mechanism ,to extend the lead to a fresh point upon the pressing of the pencil point against the writing surface. Such a pencil is disclosedin my United States Letters Patent No. 2,056,143-of September 29, 1936. My present .invention is `an improvement upon that pencil and particularly renders anyrotationiofvone element 'of the said pencil inrespect to anotherunnecessary in order to replenish thelead .in the feedingmechanism.

Also, my new pencil provides in the `feeding mechanism .a .novelarrangement of elements resulting .in a positive gripping of the lead and minimizing possible slippage of the lead in said feeding mechanism following .from long use of the pencil and consequent wearing of its parts. Other objects .and advantages .of this invention it is believed will be apparent from the .following detailed .description of a .preferred embodiment thereof -as illustrated `in the accompanying drawings in which:

Fig. 1 shows a .side view of my pencil and .of the case enclosingthe same; and

Fig. 2 is across section takenthrough the longitudinal laxis of `my pencil showing the feeding mechanism in its ordinary writing position; and

Fig. 3 is a cross section taken through the longitudinal `axis iof my pencil showing the feeding mechanism in the position it assumes upon pressing the pencil `against the Writing surface `during the leadlpoint extending operation; and

Fig. 4 is a cross section taken along the line Irl- 4 of Fig. 3; and

Fig. 5 is an exploded View of a'portion of the L, feeding -mechanism of my pencil; and

Fig. 6 is an enlarged .longitudinal cross section of .my pencil takenon the line 6--6 of Fig. 2 showing the ylead ingripped position, and

Fig. '7 is .an enlarged longitudinal cross section of my pencil taken on the line l--l of Fig. 3 showing .the .lead free to gravitate or drop during the lead extending operation.

Referring to the drawings of my pencil with its `feed mechanism in Writing position, the upper part l of my pencil, comprising clip, eraser andthe like, is threaded to screw over the housing .2, which :itself is threaded and which has about its threaded end the threaded collar 3. The .housing 2 has its lower end 4 interiorly threaded :to receive the threaded bushing 5, `the threaded bushing 5 being threaded at its lower end to ,carry thereon the tapered head 6, the upper end l of rwhich is likewise interiorly threaded.

`.Sliding within the bushing 5 is the tube .8 which, at its lower end 9, is exteriorly threaded to .carry the lpencil point housing IU. The point housing I0 has `as apart thereof the flange l2, against which abuts the compression'spring lA, the-otherend of said compression spring I4 abuttingagainsta shoulder at the end I6 of the axial bore ,l8.in.the bushing. Thus, the point housing 'Ill -is carried threadably on the tube '8 in slidable relationship .to Athe tapered head 6 .and the compression spring I4 is interposed between the said .LlJoint housing Il) :and the bushing 5.

3 Likewise, by virtue of its threadable connection with the point housing Il), the tube 8 is not only slidable With relation to the bushing 5, but is also connected therewith through the compression spring I4.

Adjacent its lower end 9, the tube 8 has the flange 26 which forms a shoulder against which the point housing I6 abuts, and above this the outside diameter of the said tube 8 is increased at 22 to form the slidable fit within the bushing 5. The uppermost end 24 of the tube 8 is flattened and squared and has drilled therein the bores 26 which receive the stub shafts 28. Pivotally mounted at their center points on the said stub shafts 23 are the levers 36.

At one of their extremities the levers 30 are bored to receive the shaft 32 which carries rotatably the bifurcated link 34. The bifurcatedlink 34, at its lower extremities, pivotally connects to the bushing 5 by the stub shafts 36. At their other extremities the levers 30 are bored to receive the shaft `38 which rotatably carries a second bifurcated link 46. The levers 30 and links 34 and 46 form a toggle joint or toggle lever means and the bifurcated link 40, at its upper ends, is pivotally connected through the stub shafts 42 to the flanged sleeve 44.

The flanged sleeve 44 is axially bored to receive the split tube 46 which passes through the tube 8 and which carries thereon a second sleeve 48, the bore of said sleeve being tapered at its lower end. It will also be noted that the bore of the flanged sleeve 44 is likewise tapered at its upper end. The sleeve 48 rides at its lower end within an axial bore in the point housing I U, said axial bore in the point housing I commencing of' a diameter slightly larger than the lead 50 and expanding in conical manner to the shoulder 52. The point housing I6 is thereabove provided with the constant diameter bore 54 up to the seat 56 and the enlarged bore 58. The sleeve 48 slides in the bore 54, and a compression spring 59 is accommodated in the bore 58 which abuts against the seat 56 on the one hand and the flange 6I) on the sleeve 4 8 on the other. The flange 60 is of a size to be slidably received in the bore 62 of the tube 8 which ends in the shoulder 64. The split tube 46 has an enlargement or flange 66 which slides within the increased bore 61 of the tube 8 and which abuts against the ange 68 of the sleeve 46, and which may abut against the shoulder 68 in the said tube 8.

It is, of course, apparent that the split tube 46 is adapted to receive the lead piece 50 and a further lead piece 69. Several lead pieces of different lengths occasioned by possible breaking of the lead may abut against each other within the split tube 46 without interfering with the operation of my pencil as will later be apparent. It should be noted that at one end 'I0 of the split tube 46, and at the other end 12, the split of the said split tube is wider and I contemplate a second splitting at these portions, across from the first. This results in the ends of the split tube having, as it were, four fingers which, as the sleeve 48 and the flanged sleeve 44 approach each other, facilitate the gripping of the lead and provide a clutch device.

As shown in part in Fig. 5, the flanged sleeve 44 is itself split or slotted at 'I4 up to the flange 88 and such slot is adapted to receive the wing-s i6, a part of the split tube 46. The wings 'I6 as shown in Figure comprise diverging ears forming a part of and extending transversely of the split tube 46. The slot 14, which extends through 4 the flange 'I8 up to the flange 80, permits the telescoping of the split tube 46 into the flanged sleeve 44 without interference caused by the said ears 76, the said ears 'I6 riding within the said slot 14, their upward movement with relation to the flanged sleeve 44 and consequently the upward movement of the split tube 46 being limited by the flange 86 which thus acts as a limiting stop. The flange 82 at the top of the flanged sleeve 44 is of an outside diameter suitable to slidably ride within the housing 2 and thus hold the feeding mechanism in alignment. The flange 82, which has a conically depressed top surface, likewise provides the base for the storage compartment 84 which contains the extra leads 86.

In showing the operation of my pencil, Figs. 2 and 6 are drawn with the feeding mechanism in writing position. Thus, in Fig. 6, the leads 58 and 69 are held rigidly in the split tube 45 by the action of the sleeve 48 and the flanged sleeve 44 on the split tube fingers at the extremities I8 and l2 of the said split tube 46. The sleeve 48 is urged into coaction with the fingered extremity l' by the compression spring 59 which abuts against the seat 56 and the flange 66, thus causing the split tube 46 to grip the lead.

At the other extremity 72, the flanged sleeve 44 is urged to coact with the said fingered extremity 'i2 by virtue of the lever action of the bifurcated link 46, the lever 36 and the bifurcated link 34, the said bifurcated link 34 being pivotally mounted on the bushing 5 which is abutted against by the large compression spring I4. The large compression spring I4, abutting against the flange I 2 of the point housing I6, urges the bushing 5 and the point housing Ill apart with respect to each other. Since the said point housing I6 is threadably connected to the tube 8, the aforementioned lever action on the flanged sleeve 44 reverses this urging, urging the said flanged sleeve 44 downwardly With respect to the point housing I8, While the compression'spring 59 urges the sleeve 48 upwardly in relation to the point housing Ill. Thus, the sleeve 48 and the flanged sleeve 44 are resliently urged toward each other causing the clutching action which grips the leads 56 and 68.

It may perhaps be helpful in considering the above relationship of elements to note that as both the compression springs 59 and I4 abut against the point housing I0, upon which the tube 8 containing the split tube 46 is threaded, and since the levering action, as stated, reverses the action of the spring I4, the springs 59 and I4 may be considered in combination to force the Sleeve 48 and the flanged sleeve 44 toward each other, thus, by virtue of the fingered extremities I0 and 'l2 of the split tube 46, gripping the lead. Of course the combination of the compression spring I4 which abuts against the flange l2 of the point housing II) and the lever action heretofore mentioned which causes the flanged sleeve 44 to be urged downwardly in relationship to the said point housing I0, said flanged sleeve 44 gripping, through the split tube 46, the lead 69, results in the lead 56 being held extended from the said point housing I6. This extension is limited by the shoulder 52.

The pressure exerted by the writer in using my pencil will thus oppose thecompression spring I4, and since the compression spring 58 urges the split tube 46 upwardly in respect to the housing I6, the resultant pressure of the lead on the writing surface equals the difference of the compression force exerted by the compression spring yI4 and the force exerted by the compression spring 59. In this way my pencil is assured of a 'positive gripping of the lead Idue to what might be called `a double clutching action which cornbines the resilient strengths of the two springs I4 and 59, 'meanwhile gaining the advantage of a `resiliently-r'iding pencil point, which feature minimizes the inconvenience of broken lead points, gouged paper and the like.

Assuming now that the lead point 5U has been Worn down and that a new extension of the lead is desired, the pencil is merely pressed point down upon the writing or any other surface. The lead point 5U, which is gripped by the split tube 46, causes the said split tube to rise in the tube 8 against the compression spring I4, which acts through the flanged sleeve 44 and the lever system. In this movement the tube 48, of course, follows the flange 66 of the split tube 46 by virtue of the compression spring 59.

In the pushing operation, when the point housing I8 comes against the writing surface, the tube 8, being threaded to the point housing I0, of course, moves upwardly with respect to the bushing 5 causing the lever system to raise the flanged sleeve 44. Of course, since the said flanged sleeve 44 still grips the split tube 46, it too is caused to rise with respect to the bushing 5, land by virtue of the lever arm relationship, the'said split tube 46 rises also in relationship to the tube 8. Meanwhile the sleeve 48 follows the flange 66 of the split tube 46. When the sleeve 48, however, reaches the shoulder 64 of the tube 8, since it is still gripping the split tube 46, the rise of the said split tube 46 with respect to the tube 8 is checked. Since the flanged sleeve 44 is rising with respect to the said tube 3 then, the said flanged sleeve 44 moves upwardly with respect to the split tube 46, and the split tube lingers at the extremity 12 are released from their gripping action.

Further pressing of the pencil upon the writing surface displaces the flanged sleeve 44 further with respect to the split tube 46 and consequently with respect to the wings 16, until the said wings 16 abut against the ilange 18. Following this abutment, the split tube I0 again moves upwardly with the flanged sleeve 44 and, due to the lever arm action, in relationship to the tube 8. Since the sleeve 48 is checked by the tube 8, the split tube 46 is thus pulled from the said sleeve 48, and the clutch is now completely released. Fig. 7 shows my pencil in this position and as is apparent, the leads 58 and 69 are permitted to drop gravitationally until stopped by the writing surface.

Of course, it is possible that when the sleeve 48 reaches the shoulder 64 of the tube 8, the flanged sleeve 44 will be gripping the split tube 46 harder than is the said sleeve 48. If this is so, the split tube 46 will continue to rise with respect to the tube 8, and the sleeve 48 being checked, will withdraw from said sleeve 48. The split tube fingers 18 are thus released from their gripping action about the lead 50.

`If this should happen, further pressing of the pencil upon the writing surface and further rising of the flanged Sleeve 44 continues to lift the split tubeV 46 with relation to the tube 8 until `the flange 66 reaches the shoulder 68. When the flange 66 reaches the shoulder 66, rise of the split tube 46 with relation to the tube 8 is checked, and since by virtue of the lever arm relationship the flanged sleeve 44 moves upwardly with relation to the said tube, the llangedlsleevel 44 must move upwardly with relation vto :the split tube 46. vThis causes the split tube fingers 12 toAbe released from their gripping action about the 'lead 69 and causes the clutch to be completely released.

From the above, Vit will be seen that whether the sleeve 48 or the flanged sleeve 44 first releases the fingers 10 or 12, a complete declutching from pressure of the pencil upon the writing surface results'. Otherwise stated, declutching is positive, by virtue of either the wings 16 or the shoulder 68, and pressure of the pencil upon the writing surface must result in a complete releasing of the leads 50 and 69 and an allowing of the said leads to drop gravitationally downwards until stopped by the writing surface.

Pressure upon the pencil against the said writing surface is now released. As the bushing 5, urged by the compression spring I4, moves upwardly with respect to the point housing I0 and the tube 8, the lever system displaces the flanged sleeve 44 downwardly, removing the force exerted on the wings 16 by the flange 18. Further downward movement of the said flanged sleeve 44 pulls the said flanged sleeve 44 over the split tube 46 to gripping position while forcing the split tube 46 into gripped position within the sleeve 48. This alignment of the elements has been heretofore described and results from 'the fact that the compression spring I4 and the cornpression spring 59 both abut against the point housing I8, the direction of force of the compression spring I4 being reversedb'y the lever action to squeeze, in a manner of speaking, the split tube 46 between the sleeve 48 and the flanged sleeve 44.

Now that the clutchlis in, the hanged sleeve 44 carries the split tube 46 downwardly and, of course, the lead. The flange 66 abutting against the flange 60 of the sleeve 48 moves the said sleeve 48 downwardly against the compression spring 59 until the said sleeve 48'rests in seat 52. This movement is, y`of course, Vby virtue of the fact that the compression spring I4 overpowers the compression 'spring 59. Thus, the lead point 56 which, in the last-mentioned movement, is gripped by the split tube 46 is extended from the point housing I0. Asis plain from the above description and from Fig. 6, since the lead is positively gripped, and since the flange 66 of the split tube 46 abuts the flange 60 of the sleeve 48 which in the position shown in Fig. 1 abuts the shoulder 64 of the'tube 8, the length of lead point 5D which is extended from the point housing III will be v"equal in length to the distance shown in Fig. 6 between the flange 60 and the shoulder 64.

As the lead point is intermittently worn down, and as new extensions of the said lead point occur in accordance with the preceding description, the height of the lead 69 will gradually diminish until below the top of the llange 82. When this occurs another lead 86 will drop in behind the lead 69 gradually taking its place in the downward progress through the feeding mechanism until finally the lead 69 will have assumed the position of the lead 58, and the lead 86 the position of the lead 69. By Virtue of the deolutching arrangement of ymy pencil, these different pieces of lead always abut each other within the feeding mechanism and form, in effect, a continuous length of lead. O-ne after another of the pieces of lead 86 inthe storage compartment 84 gravitationally feed into the feeding mechanism, and` itisfthus unnecessary to take apart my lpencil fortli'e purpose of 'replenishing lead, except when the entire supply within the storage compartment 84 has been exhausted.

Having fully described my invention, it is to be understood that I do not wish to be limited to the details herein set forth, but my invention is of the full scope of the appended claims.

I claim:

l. A device of the class described comprising: a housing; a bushing in said housing rigid with respect to said housing; a second housing slidable within said rst housing; resilient means between said first and said second housings; a tube threaded in said second housing; said tube being slidable within said bushing; a lead receiving tube slidable within said nrst tube; lower clutch means adapted to releasably grip said lead, said clutch means comprising a lower sleeve slidable on said lead receiving tube, said sleeve having a tapered bore, and nge 1s comprising the lower extremity of said lead receiving tube; upper clutch means adapted to releasably grip said lead, said clutch means comprising an upper sleeve slidable on said lead receiving tube, said sleeve having a tapered bore, and nngers comprising the upper extremity of said lead receiving tube; and lever means associated with said bushing, said upper sleeve and said first tube and adapted to actuate said clutches into or out of gripping engagement with said lead, there being a spring interposed between said second housing and said lower sleeve.

2. A device of the class described comprising: a housing; lead feeding mechanism slidable within said housing, said lead feeding mechanism including a lead receiving tube, upper clutch means co-acting with said lead receiving tube to cause said lead receiving tube to grip lead therein, and lower clutch means co-acting with said lead receiving tube to cause said lead receiving tube to grip lead therein; and a lever system operatively connected with said upper clutch means and said lower clutch means to actuate said upper and lower clutch means.

3. A device of the class described comprising: a housing; lead feeding mechanism slidable within said housing, said lead feeding mechanism including a lead receiving tube, and clutch means co-acting with said lead receiving tube to cause said lead receiving tube to grip lead therein or to allow said lead receiving tube to permit lead to slide freely therethrough; spring means providing resilient relationship between said housing and said feeding mechanism; and lever means operatively connecting said housing and said lead feeding mechanism, said lever means coacting with said spring means normally to encourage co-action between said clutch means and said lead receiving tube, said lever means being adapted to release said lead receiving tube from said clutch means when said housing is moved downwardly in relationship to said lead feeding' mechanism.

4:. A device of the class described comprising: a housing; a second housing slidable within said first housing; lead feeding means within said rst and second housings, said feeding means including a lead receiving tube, upper clutch means coacting with said lead receiving tube and lower clutch means co-acting with said lead receiving tube; a spring providing resilient relationship between said second housing and said iirst housing; a second spring providing resilient relationship between said second housing and said lower Aclutch means; and alever-operatively connectl8 means, said two springs and said lever normally combining to urge said upperand said lower clutch means into co-action with said lead receiving tube to cause the gripping thereby of lead therein,

5. A device of the class described comprising: a housing; a bushing in said housing rigid with respect to said housing; a second housing slidable within said first housing; resilient means between said rst and said second housing; a tube threaded in said second housing, said tube being slidable within said bushing; a lead receiving tube slidable within said tube; lower clutch means adapted to releasably grip said lead, said clutch means comprising a lower sleeve slidable on said lead receiving tube, said sleeve having a tapered bore, and fingers comprising the lower extremity of said lead receiving tube; upper clutch means adapted to releasably grip said lead, said clutch means comprising an upper sleeve slidable on said lead receiving tube, said sleeve having a tapered bore, and ngers comprising the upper extremity of said lead receiving tube; a lever system comprising a bifurcated link pivotally connected with respect to said first housing, a lever pivotally connected to said rst tube and to said bifurcated link, a second bifurcated link pivotally connected to said lever and pivotally connected to said upper sleeve; and a spring interposed between said second housing and said lower sleeve.

6. A device of the class described comprising: a housing; lead feeding mechanism slidable within said housing, said lead feeding mechanism including a lead receiving tube, and upper clutch comprising an upper sleeve slidable on said lead receiving tube, said sleeve having a tapered bore, and iingers comprising the upper extremity of said lead receiving tube, and a lower clutch comprising a lower sleeve slidable on said lead receiving tube, said sleeve having aftapered bore and lingers comprising the lower extremity of said lead receiving tube; and a lever system operatively connecting said upper and lower clutches to cause said clutches to grip said lead.

7. A device of the class described comprising: a housing; a lead feeding mechanism within said housing, said lead feeding mechanism including a lead receiving tube, fingers at the upper eX- tremity of said lead receiving tube, an upper sleeve slidable on said lead receiving tube and having a tapered bore, fingers at the lower extremity of said lead receiving tube, and a lower sleeve slidable on said lead receiving tube and having a tapered bore.

8. A mechanical pencil comprising, elongated housing, tube means mounted for longitudinal reciprocation within said housing and having one end extendable from and retractible with respect to one end of said housing and being formed with a lead exit opening, a spring connected to the said housing and tube means and urging and normally positioning said tube means end in extended position from said housing end, a lead tube slidably carried by said tube means for relative longitudinal movement and in registration with said exit opening, said lead tube having a normal diameter permitting the free passage of lead therethrough and being compressible for gripping lead positioned therein, a clutch sleeve slidably mounted upon said lead tube and within said tube means and having a tapered bore wall engageable with said lead tube for compression thereof upon movement of said lead tube to said wall, a second spring normally urging said: leadi tube into engagementwith, said wall; and means` connected; to said: housingand tube means and lead tube.. and actuated; upon movement, ofv said tube. means end: toward said housing against the. resistance. of said. -rstspring to displace said lead tubeaway fromsaid tapered wall to thereby permit passage.. ofl leadv through said lead tube.

9, In a` pencil; ot' the. character described, an elongated pencil: housing, a tube. mounted: for reciprocation in said housing and having` a pointed end formed. with a lead discharge opening extendable from. and retractiblewith respect to one end of saidj housing, a lead tube-v slidably mounted within said first tube in registration with said opening and having a normal diameter permitting the free.. passage ofv lead. therethrough and being compressible. for gripping lead therein, a clutch sleeve mountedwithinV said first tube. andY surrounding said lead. tube and moveable relative thereto between positions respectively compressing and releasing saidtube, resilient means urging and normally positioningA said first tube end in extendedposition from said housing and said clutch sleeve in compressing position on said tube, and means actuated bycontraction of said first tube end relative to said housing and against the action of said resilient means to effect a relative displacement of said second tube and clutch, sleeve to released position of said second tube therebypermitting the Passage i leed therethrough.-

10. In a pencil of the character described, an elongated pencil housing, a tube slidably mounted within said housing for longitudinal reciprocation and havingy a pointed lead,y supporting end extendable from and retractible with respect to one end of said housing, a lead tube slidably mounted within said rst tube and having a normal diameter permitting the free passage of lead therethrough and being compressible for gripping lead therein, a clutch sleeve surrounding said second tube, said second tube being movable relative to said clutch sleeve to positions relatively compressing and releasing said second tube, spring means urging and normally positioning said rst tube end in extended position from said housing end and said second tube in compressed position within said sleeve, a lever pivoted intermediate its ends to said rst tube and having one end pivotally connected into said housing and its other end pivotally connected to said second tube and functioning upon displacement of said first tube end toward said housing end to eiect a movement of said second tube to released position with respect to said sleeve thereby permitting the passage of lead therethrough.

11. In a pencil of the character described, an elongated pencil housing, a tube slidably mounted within said housing for longitudinal reciprocation and having a pointed lead supporting end extendable from and retractible with respect to one end of said housing, a spring connected between said housing and tube and urging the extension of said tube end, a lead tube slidably mounted within said first tube and having a normal diameter permitting the free passage of lead therethrough and being split for compression at an end adjacent to said first tube end for gripping lead therein, a clutch sleeve having a tapered bore slidably mounted upon said second tube end and within said first tube, means limiting the relative longitudinal movement of said sleeve in said rst tube, a lever pivoted intermediate its ends to said first tube and having one end pivotally connected to said housingv and; its other.- end: pivotally con. nected to said second tube and normally. urging said second tube into compressed position` of said end thereof insaid sleeve,said lever being displaced by saidV first tube upon movement of said rst tube end. toward said housing. end so as to Withdraw said second tube end from the tapered bore of said sleeve to `thereby release said second tube end for. expansion and passage of lead. therethrough.

12. In a pencil of the character described, an elongated pencil housing, a tube. slidably mounted within said housing for longitudinal. reciprocation and having a pointed lead. supporting end extendable from and retractible with respect to one end of said. housing, a spring connected between said housing and tube andurging the extension of said tube end, a lead tube! mounted for longitudinalmovement within said rst tube and having a normal diameter permitting the free. passage of leadtherethrough, the. opposite ends of said second tubebeing compressibleto grip lead therein, a pair ofv clutch sleeves mounted on the opposite ends of said second tube and movable with respect thereto between positions compressing andreleasing said second tube ends, a lever pivotally. mounted intermediate its ends to said, rst tube, a link pivotally securing. one. end of said lever toA said housing, a second link pivotal'ly securing the opposite end ofsaid leverto one of said clutch sleeves, said last-named clutch sleeve having a limited loss motion connection to. the adjacent end of said second'tube, the lever and link connection between said rst tube and said lastnamed clutch sleeve and said second tube being such as to normallyposition said clutch sleeves in position of compression of the opposite ends of said second tube, said lever being motivated by displacement of said rst tube end toward said housing end to displace said clutch sleeves and second tube ends to released position of said second tube ends thereby permitting the passage of lead therethrough.

13. In a pencil of the character described, an elongated pencil housing having an open lower end, a tube slidably mounted within said housing for longitudinal reciprocation and having a pointed lower end extendable from and retractible with respect to said housing end, a spring corinected between said housing and tube and urging the extension of said tube end, a lead tube slidably mounted within said rst tube and having a lower end adjacent the lower end of said rst tube and an upper end extending from the upper end of said rst tube, said second tube having a normal diameter permitting the free passage of lead therethrough and being split at its upper and lower ends to permit compression of said tube ends for gripping lead therein, clutch sleeves having tapered bores mounted on the upper and lower ends of said second tube and having first positions thereon compressing said 4second tube ends and second positions thereon releasing said ends to permit passage of lead therethrough, and a lever pivoted to said first tube and operatively connected to said housing and said second tube and sleeves to position the latter in said rst position in the normal extended position of said first tube end and being actuated upon displacement of said first tube end toward said housing end to displace said sleeves and second tube to said second position releasing said second tube ends for passage of lead therethrough.

14. A lead feeding unit for mechanical pencils including a pair of lead gripping clutches mounted spaced apart in longitudinal relation to each other, toggle lever means connecting said clutches, said lever means 4being pivoted between its ends whereby when pressure is exerted against the writing end of said unit said clutches are released to permit a writing lead to slide freely in said clutches and when the pressure is released the writing lead is automatically ejected out of the writing end a predetermined degree and said clutch unit grips the lead firmly in writing position.

15, In a mechanical pencil including a lead reservoir for a supply of writing leads, a lead feeding unit mounted in the forward end of said pencil below said lead reservoir, said unit including a pair of longitudinally spaced lead gripping clutches through which the writing lead slides from said reservoir, a pair of toggle levers interposed between and pivotally connected to said pair of clutches and spring means normally spacing said pair of clutches toward each other and adapted to permit the writing end of said unit to be de` pressed into the barrel of said pencil and to vsimultaneously release said clutches to permit a writing lead to slide freely from said reservoir into said clutch unit, said clutch unit being adapted to grip the lead fed into it and eject the same a predetermined degree out of the writing end of said unit when pressure is released on the writing end of said clutch unit. i

16. In a mechanical p'encil comprising a lead reservoir, an automatic lead feeding clutch unit, means in said unit for receiving a writing lead from said reservoir and ejecting the same a predetermined degree at a time by pressure against the writing end of said pencil and unit and including said lead feeding unit including a pair of longitudinally spaced apart clutch means which reciprocate to receive and eject the writing lead, toggle lever means connecting said clutch means of said unit to cause said clutch means to operate in unison when pressure is exerted against the writing lead to release the same and to automatically grip the lead and force it into writing position a degree at a time when pressure at the writing end is released and spring means for normally holding said clutch means toward each other.,

17. In a mechanical pencil including a lead reservoir for eXtra writing leads, a clutch feeding unit having a writing end projecting from the barrel of said pencil, said unit including longitudinally spaced means for gripping and releasing a writing lead by the action of clutch means, Ispring means for normally holding said clutch means in gripping position and lever means connecting said clutch means in a manner to cause the same to operate in unison and be released from gripping the lead when pressure is exerted against the writing end of said pencil and to grip the lead and hold it in projecting writing position lwhen pressure on the Writing end of the pencil is released.

JESSE J. RO-BBINS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,956,143 Robbins Sept. 29, 1936 2,078,433 Winter Apr. 27, 1937

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