US3850531A — Automatically feeding lead pencil

Claim 1

Independent Claim 280 words

An automatically feeding mechanical lead pencil comprising: a. a tubular external barrel; b. an elongated longitudinally slotted sleeve rotatably disposed within the barrel in snug friction fit and terminating outward of the barrel in a tapered end having an axial lead-receiving bore and means engaging the barrel to limit movement of the barrel toward the said tapered end; c. a tubular externally threaded and longitudinally slotted drive screw disposed within the sleeve and having one end journaled for rotation in the bore of the tapered end and capable of longitudinal movement with respect thereto, means limiting the longitudinal movement of the screw in the direction of the tapered end, the thread-receiving bore and the opening in the tubular screw being coaxial; d. nut means surrounding the drive screw and threadedly engaging the threads on the outside of the drive screw and having key means reciprocally disposed in the slot in the sleeve; e. lead-engaging means slidably disposed in the drive screw and having an outward projection extending out through the slot in the drive screw and engaged by the nut means; and f. drive means connected between the other end of the drive screw and the external barrel and adapted to bias the drive screw toward the pointed end and limit the longitudinal movement of the lead with respect to the barrel in a direction away from the tapered end and to convert slight longitudinal movements of the lead relative to the barrel as produced in natural handwriting into the rotary movement of the screw relative to the sleeve and nut means for the purpose of driving the lead outward of the pencil at a rate complementary to lead usage.

Claim 2

Dependent Claim 280 words

An automatically feeding mechanical lead pencil comprising: a. a tubular external barrel; b. an elongated longitudinally slotted sleeve rotatably disposed within the barrel in snug friction fit and terminating outward of the barrel in a tapered end having an axial lead-receiving bore and means engaging the barrel to limit movement of the barrel toward the said tapered end; c. a tubular externally threaded and longitudinally slotted drive screw disposed within the sleeve and having one end journaled for rotation in the bore of the tapered end and capable of longitudinal movement with respect thereto, means limiting the longitudinal movement of the screw in the direction of the tapered end, the thread-receiving bore and the opening in the tubular screw being coaxial; d. nut means surrounding the drive screw and threadedly engaging the threads on the outside of the drive screw and having key means reciprocally disposed in the slot in the sleeve; e. lead-engaging means slidably disposed in the drive screw and having an outward projection extending out through the slot in the drive screw and engaged by the nut means; and f. drive means connected between the other end of the drive screw and the external barrel and adapted to bias the drive screw toward the pointed end and limit the longitudinal movement of the lead with respect to the barrel in a direction away from the tapered end and to convert slight longitudinal movements of the lead relative to the barrel as produced in natural handwriting into the rotary movement of the screw relative to the sleeve and nut means for the purpose of driving the lead outward of the pencil at a rate complementary to lead usage.

Claim 3

Dependent Claim 97 words

An automatically feeding mechanical lead pencil as claimed in claim 1 wherein the drive means comprise a head fixed on the upper end of the drive screw, the head having a first horizontal surface, an element having a second horizontal surface mounted on the inside of the barrel, the second surface opposing the first surface, means operative between the surfaces for converting reciprocal movement of the first surface relative to the second surface to step-by-step rotary movement of the head and screw, and a spring disposed axially of the pencil biasing the screw toward the tapered end.

Claim 4

Dependent Claim 96 words

An automatically feeding mechanical lead pencil as claimed in claim 2 wherein the means operative between the surfaces comprise a circular ratchet surface with generally radially disposed ratchet shoulders on one of the surfaces and at least one stiffly yieldable strut on the other surface offset from the center thereof extending toward the ratchet surface at an angle which induces rotation of the screw whereby as the surfaces are brought toward each other, the end of the strut engages the ratchet surface and the strut flexes adjacent the said other surface to step about said head.

Claim 5

Dependent Claim 258 words

An automatically feeding mechanical lead pencil as claimed in claim 1 wherein the drive means comprise a head fixed on the upper end of the drive screw, the head having on both the upper and lower surface thereof a circular rachet surface having generally radially disposed ratchet shoulders, the shoulders on both ratchet shoulders facing in the same direction; and a ratchet ring is provided about the screw and secured to the barrel above the sleeve, the ratchet ring having stiff wires extending up from the ring and angled generally in opposition to the ratchet shoulders on the lower surface of the head, and a stop element having a lower surface disposed within the barrel and transversely of the pencil, the undersurface of the stop having stiff wires extending down therefrom and angled generally in opposition to the ratchet shoulders on the lower surface of the head, and a stop element having a lower surface disposed within the barrel and transversely of the pencil, the undersurface of the stop having stiff wires extending down therefrom and angled generally in opposition to the ratchet shoulders on the upper surface of the head, and spring means from the stop element extending down to the head and urging the screw downward toward the tapered end, whereby the reciprocation of the lead in normal handwriting and the consequent reciprocation of the head causes the head to be rotated as it alternately is engaged by the wires above and below the head respectively to step the head around and drive the lead outward.

Claim 6

Dependent Claim 29 words

An automatically feeding mechanical lead pencil as claimed in claim 4 wherein the stop element is adjustable longitudinally of the pencil to control the rate of feed of lead.

Claim 7

Dependent Claim 129 words

An automatically feeding lead pencil comprising a barrel having at one end thereof tapered end means, the tapered end means being formed with an axial bore-receiving lead, means permitting the lead to reciprocate axially of the barrel to a limited extent in normal writing as the lead is engaged and disengaged with paper, lead feeding means within the barrel comprising cooperating screw means and nut means, the nut means normally held from rotating by the barrel and engaging the lead, and drive means for converting the said limited reciprocal movement of the lead itself to rotary movement to rotate the screw means to move the nut toward the tapered end means and thereby replenish the lead at a rate roughly complementary to the rate of wear of the lead.

Claim 8

Dependent Claim 129 words

An automatically feeding lead pencil comprising a barrel having at one end thereof tapered end means, the tapered end means being formed with an axial bore-receiving lead, means permitting the lead to reciprocate axially of the barrel to a limited extent in normal writing as the lead is engaged and disengaged with paper, lead feeding means within the barrel comprising cooperating screw means and nut means, the nut means normally held from rotating by the barrel and engaging the lead, and drive means for converting the said limited reciprocal movement of the lead itself to rotary movement to rotate the screw means to move the nut toward the tapered end means and thereby replenish the lead at a rate roughly complementary to the rate of wear of the lead.

Claim 9

Dependent Claim 57 words

An automatically feeding lead pencil as claimed in claim 6 wherein the drive means comprises a head on the inner end of the screw having a radial ratchet surface and stiffly yieldable means connected to the barrel adapted to step around the head by engagement of the ratchet surface as the screw and head reciprocates in writing.

Claim 10

Dependent Claim 29 words

An automatically feeding lead pencil as claimed in claim 7 wherein the stiffly yieldable means is adjustable longitudinally of the barrel by adjustment means to control rate of feed.

Claim 11

Dependent Claim 60 words

An automatically feeding lead pencil as claimed in claim 8 wherein a longitudinally slotted sleeve is disposed inside the barrel with a friction fit and the sleeve holds the nut means from rotating, the tapered end of the pencil being fixedly carried by the sleeve, and the larger portion of the tapered end being of greater diameter than the barrel.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1977-11-25	1978-05-27	1978-11-26	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1981-11-25	1982-05-27	1982-11-26	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1985-11-25	1986-05-27	1986-11-26	$7700.00	Window Closed / Lapsed

Automatically feeding lead pencil

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