US1913528A - Pencil - Google Patents

Description

June 13,l 1933.

H. WHITE PENCIL Filed NOV. 7, 1929 emp o .UNITED STATES PA'rENT ori-ics nanou aunar wnn'n, or amm, emunio, calura applicazione :wenn: 1, .ma serial No. 405,430.

Thiswinvention relates to a mechanical pencil y'cfa ty in which a propellingmeched yfor projecting the markjiigglead be on or, retracting it within, the pencil, an aocordin to my present. improvements the invention is vcharacterized in that the pencil comprises, a tubular casing provided ,with a sprin tensioned tip which recedes relatively to te casing when pressure is applied to it spring tension and advances when the pressure lsreleased, a lead holder and a pro mechanism for theV lead holder ac-4 pelhn n tuatedg by the tip at each complete cycle of its receding and advancingmevements for a step by step progression of the lead holder through the casing towards the tip. The invention is further characterized in that pressure actuated means aref provided for actuating the propelling mechanism to retractthe lead within the casing. Y

For an understanding of the invention reference is to be had to the followin description and tothe accompanying rawingz in which i ig. 1 is alongitudinal section iof a me-` chamcal pencil constructed according to this invention; f

Fig. 2 is a fragmentary longitudinal seotion showing a modification of the propelling means; y f

Fig.l 3 is a cross'section on a'line -zl,

Fi 2; v y ig- 4 is a fra entary longitudinal section showing afilli'lthermodiication of the pro lling mechanism;

Like characters of reference refer to like parts throughout the specification and drawhe pencil shown in Fig. 1 comprises a tubular casingl, provided with an axial bore 3 extending inwardly from its tip end, and

. a counter bore 4 extending from the bore 3 to its head. The casing is provided with an axiall movabletip 2, which protrudes beyond t e end of the casing and is con` 'structed with a tubular sleeve 5. The tubular sleeve 5 is, enteredin the bore 3 and for overcoming the ing, at each step of the counter, bore 4, and, provided, intermediate `its ends, with a peripheral shoulder 6 which ,engages the shoulder -7 at the junction of the re .and counter bore for limiting the outward movement of the sleeve and tip. 55

yFormed through the pointed end of the sleeve or tip is a bore 9 ofk corresponding diametric dimension to the marking lea l and extending from the inner end of 'the bore 9 to the inner end of the tubular sleeve 69 is a counter bore 10 .of corresponding diametric dimension to the lead holder 11. Adjustable within the tubular casing 1 is a barrel 12, extending from vthe head t0- Wards the tip end of the casing and over-v 35 lapping the inner end of the 'sleeve 5. Coiled on the lsleeve 5 and abutting against the shoulder 6 and the adjacent end of the barrel 1 2 is a sprin 13 for advancing the sleeve and ti l rested y ,the engagement of the peripheral shoulder 6 with the shoulder 7 ,-the tip receding relatively to the casin when suf; ficient pressure is applied toit or compressing the spring 13, and advancing again 5 when the pressure is released.

a Within the` barrel is an axially movable 4 rack 14 comprising part ofmthe propelling mechanism, and connected with the rack 14 is a lead holder 11. The rack meshes with 8 and is actuated by a gear wheel 16 mounted on a stud 17 in the bore of the barrel 12, and, during the rotation of the gear wheel in a clockwise direction, advances towards the sleeve for a step by step progression of the i 85 lead holder through the casing, for protrudrogression, a predetermined length of lead beyond the point of the tip, The rack, during the rotation of the gear Wheel in a counter clockwise direction, recedes towards the head of the pencil and retracts the lead within the point of the tip. Secured to the side faceof the gear Wheell is a ratchet wheel 18, the diameter of which is less than that of the gear Wheel. 95

Connected to the inner end of the sleeve 5 is a ratchet leverl 19 which meshes with the teeth of the 'ratchet Wheel 18 during the advancingl movement of the sleeve for relat1vely to the casing until ar- 7 canrasirig the rotation of the ratchet wheel. 18 1m by the compression of the 4teeth and the gear wheel 16 in a clockwise direc- `tion, andslides over the teeth of the ratchet wheel, without imparting motion to it, during the receding movement of the sleeve.

vThe barrel 12, at or near the head of the against the abutment and the inner surface of the cap is a spring 25 which normally resses the cap outward until its movement 1s arrested by the engagement of the stop 23 with the outer end of the slot 20. Connected with the core 22 is an arm 26 extending from the cap in the direction of the gear and ratchet wheels, and at the inner end of the arm 26 is an inclined face 27 opposed to the ratchet lever 19. Pivoted to the arm 26 is a pawl 28 which engages the teeth of the gear wheel 16 when the cap is pressed inwards, and which becomes disengaged from the gear wheel when the cap moves outwards to its normal spring pressed posi tion. The pawl 28 is held in the position shown by a s ring which holds it against of tllie ratchet wheel 18 when the arm 26 moves downwardly and permits it to 'slide over the teeth when the arm 26 is moved upwardly. A releasing Apawl 29 is ivoted between the arm 26 and the ratchet ever 19, and one side of the pawl 29 has an moves away from the gear wheel 16 thepressure on the face of the pawl 29 is removed, and being free-swinging is returned to its normal position by the resiliency of the ratchetlever 19. At the upper end of the rack 14 is a ,friction band 31 which engages the inner surface of the barrel and prevents the` inadvertent movement of the rack axially of the pencil.

For feeding the marking lead throu h the ncil sufficient pressure is applied to t e tip or causing it to recede relatively to the casing and move the ratchet lever 19 in the'direction of the cap 21, the teeth of the ratchet lever during this movement sliding past the teeth of the ratchet wheel 18 without causing -its rotation in either a clockwise or counter clockwise direction, and the receding movement of the tip being limited only t e spring 13. When the pressure is released, the sprm advances the tip until the peripheral shou der 6 engages the shoulder 7 and arrests the MVM- ing movement. During the advancing movement of the sleeve the teeth of the ratchet lever 19 engage the teeth of the ratchet wheel 18 and vrotate it in a clockwise direction. The ratchet wheel, is secured to the gear wheel 16, band imparts to it a corresponding rotation. The ear wheel when rotating in a clockwise direction advances the rack towards the sleeve' and pencil tip anda corresponding movement of the marking lead through the bore of the tip. The diameter of the gear Wheel 16 being greater than the diameter of the ratchet Wheel 18, the teeth of the gear wheel move over a longer arc than those of the ratchet Wheel and impart a longer movement to the rack. For example, if the ratio of the diameter of the gear wheel 16 to the diameter of the ratchet wheel 18 is two to one and the movement of the tip is one-sixteenth of an inch, the travel of the tip, during the advancing movement will approximate one-sixteenthpf an inch and the travel of the rack, lead holder and marking lead approximate one-eighth of an inch, consequently if the point of the lead is in the same plane as the point of the tip at the commencement of the receding movement the marking lead will be projected one-eighth of an inch beyond the tip at the completion of its advancing movement.

The feed of the marking lead through the pencil tip is regulated by the adjustment of the barrel 12 in the casing, that is to say. when the barrel is adjusted towards the shoulder 7 the length of movement ofthe tip is less than when the barrel is adjusted away from` the shoulder. For retracting the lead the cap 21 is pressed inwards and during its inward movement the inclined face 27 of the arm 26 engages the inclined face 30 of the releasing pawl 29 and forces the releasing pa'wl into engagement with a ratchet lever 19 and displaces the latter from its normal position for disengaging its teeth from the teeth of the ratchet wheel 18 to permit of the free revolution of the ratchet wheel 16 in a counter clockwise direction. The continued movement of the cap forces the arm 26 in the direction of the gear wheel 16 and brings the pawl 28 into of which are normally vin mesh with the vided with ratchet teeth 37 actuated by a teeth of the ratchet wheel` V18; an arm 33 fulcrumed at one end to a lug 34 in the barrel 12 and knuckled at the other end to the arm 32, and a link 35, connected with the arm 5 33 interjacent thefulcrum 34 and the arm 32 and with the inner end of the sleeve 5.

In the construction shown in Fig. 4 the rack, ratchet wheel and gear wheel' are dispensed with and the lead holder 36 is procoi'npound `lever comprising a ratchet arm 38 engaging the ratchet teeth 37; an arm 39 fnlcrumed'to a lug 40 within the barrel and knuckled to the ratchet arm 38, and a link 41 is connected ywith the inner end of the sleeve and the arm 39 interjacent its fulcrum and its knuckle connection withthe ratchet arm 38. Springs 42 and 43 bearl f struction the cap 'is provided with an arm vancing movement of the 44 having a bevelled face 45 which engages with a corres ndin ly bevelled face 46 at the head of t e ratcet arm 38 for displacing.the ratchet arm from the'ratchet'teeth 37 when the` lead holder and marking lead are to be retracted within the, pencil tip, which, for instance, may be eiected by pressing upon the forcing it back into t e bore of the tip when the ratchet arm is displaced. 'n

Having thus fully described my inven tion, what I claim as new and desire to secure by Letters Patent is 1 1i. A mechanical pencil comprisin a casing provided with a spring presse pencil tip, which recedes when suilicient pressure is applied to it for overcomin thespring pressure and which advances w' enthe pressure is released, and a propellingmechanism for the marking lead actuated by the pencil tip at each complete cycle of 4its receding and advancing movements for advancing the propeller mechanism a greater `distance than the advancingvmovement of the pencil tip and rejecting a predetermined length of marEing lead beyond it.

2: A mechanical pencil comprising a tubular casing'I having a spring` pressed pencil ti which reoedes relative y to the casing w 'en pressure is applied for overcoming the spring pressure and advances when the pressure 1s released, a lead holder, a pro-v `pellingmechanism for the lead holder, and operable means actuated b the pencil tip .atA each complete cycle of its receding'and advancing movements for advancin the lead holder a greater ydistance than t e adncil tip and rojecting a predetermined ength of mar ,'ng lead beyond it., y y

3. A mechanical pencil as claimed in claim 1 provided with `means for actuating the oint ofthe lead and pro lling mechanism to retract the lead wit in the casing.

4. A mechanical pencil as claimed in claim 1 comprisin a pencil tip provided with a sleeve slidab e axially of the casing, a rack for the lead holder, and actuating means operably connected with the sleeveA for advancing the lead holder and rack step`by sltlep, through the casing, in the direction of t e tip.`

5. A mechanical pencil as claimed in claim .1 in which the propellin mechanism comprises a rack for the lea holder, a ratchet wheel a gearwheel meshing with the rack, unitedlyrotatabley with the ratchet wheel, and a ratchet lever connected with the pencil tip for rotating the ratchet and gear wheels and eii'ectin astep b step progression of the rack an lead hol er throu h the casing in the direction of the ncil tip.

6,'A mechanical pencil as claimed in claim the rack an lead holder through the casing in the direction of the pencil tip, and means for displacing the ratchet lever from the within the pencil.

7. A mechanical pencil as claimed in claim 1 in which the propelling mechanism comprises a rack for the lead holder Aa ratchet wheel,a gear wheel. meshing wit the rack unitedly rotatable with the ratchet wheel a ratchet lever connected with the pencil tip for rotating the ratchet and gear wheelsk and eiecting a step by step progression of the rack and lead holder through the casing in the direction of the pencil tip, and means for displacing the ratchet lever from the ratchet wheel fo'r thelretraction of the lead within the pencil, consistingl of a spring pressed cap for the casing aving an arm extending in the direction of the ratchet and A gear wheels,

,with a shouldered sleeve slidable axially of the casin la barrel within the casing, a spring cci ed on the sleeve between its shoulder and the adjacent end of the barrel, a rack for 'the lead holder, 'a ratchet Wheel, a gear wheel meshing with the racl-r unitedly rotatable with the ratchet wheel, and a ratchet Vand eil'ectin a step by step progression of ratchet wheel for the retraction of the lead 4 y l ananas lever connected with the sleeve for rotating' the ratchet and gear wheels and effecting a step by step progression of the, rack and lead holder. in the-direction of the tip.

A mechanical pencil comprising a casing, a lead holder movable axiall within 'y the casing, a eiring pressed pencil7 tip Afor the casing rec ing into it when pressure is applied o r overcoming the ressure, and means actuated by the pencil) tip for advancing the lead holder a greater distance than the progressive movement of the pencil tip at each complete cycle of movement of the latter. A

11. In a mechanical pencil as claimed in I .claim 10 a gear wheel and a ratchet wheel, V

unitedly rotatable, and corresponding racks `for actuating the lead holder and advancing it at each complete cycle of movement a greater distance than the distance travelled by the pencil tip. y 12. In a mechanical pencil as claimed in claim 10 means for selectively increasing or decreasing the travel of the pencil tip and determining the distance the lead holder travels during its advancing 'movement and the length 'of marking lead projected beyond the pencil tip when the advancing movement is com leted'.

13. n a mechanical pencil as claimed in claim 10 differential gears for causing the united movement of the lead holder and the pencil, tip, said gears advancing the lead holder during the advancingmcvement of the4 pencil tip for al greater distance than the latter and during the receding movement of the pencil t-ip under pressure permitting the lead holder to remain inactive.

14. A mechanical pencil comprising a casing-having a spring pressed pencil tip which recedes into the casing when pressure is applied to it for overcoming the pressure and returns again to its advanced sition lwhen the pressure is removed, a lea holder within and movable axially'of the ncil casing, operable means actuated by t e pencil ti during its advancin movement for adl vancing` the lead hol er a'distance greater than thatof-the said tip for projecting the lead beyondv the latter 1n its advanced position, said operable means being inactlve when pressure is applied to" the pencil tip for its receding movement. 55 Dated at Toronto, Ontario, the fifth day of October 1929.

p riARoLD ALBERT WHITE.

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