US1728711A - Pencil - Google Patents

Description

Sept. 17, 1929. T. YOSHIMATSU PENCILI Filed June 23, 1927 III III/III Ill/ INVENTOR. 7 )flshima-lth Wax/4 2 64% ATTORNEYS.

spectivel'y.

Patented Sept. 17, 1929 1 UNITED STATES,

'ranao vosnma'rsu, or azianu-xu, 'roxYo-snI,

rnncn.

Application fled June 28, 1927, Serial No. $200,964, and in Japanlarch 19, 1987.

' liable to cause breakage of the lead propelling mechanism 'or the lead. The invention is proposed to eliminate these disadvantages and 15 consists in the novel construction, combinati'on and arrangement of the parts.

In the accompanying drawings i Fig. 1 is a side elevation vof my pencil,

partly in section.

Fig. 2 is a longitudinal cross sectional view of the same taken on line AB of Fig. 1.

Figs. 3 and 4 are perspective views illus-' trating a stationary and a rotatable guidebush for the lead propelling mechanism're- Referringto the drawings a barrel or casing 1 is formed of thin tubular material which is adapted to enclose a lead propelling mechanism. Connected to the fore end of the barrel 1 is a conical operating tip or writing end 2 having an end vopening 3 in which a lead 4 fits snugly and a centrahlorigitudinal perforation 5 extendingthroughout'its length. Screwed-in the other end of the barrel 1 is aneraserholder 6, which carries an eraser 7, and has a screwed cap 8. The rear end of the operating tip'2 is of such a reduced diameter as to fit closely within the fore end of the barrel 1 and is formed with an .annular groove 9 of a substantially U-shaped'eross section. The barrel L is formed with an annular groove 10 of a substantially V-sha ed cross section in the fore end to be in su stantially opposite relation to the groove 9 of the operating-tip 2 when the same is inserted in the barrel. The operatingtip 2 is inserted with its rear end in the fore end "of the barrel 1 and is secured in lace by meansof a spring ring 11 interpose in the grooves 9 and, 10, but is ree- A corner of the -rearendof the slot l i is 1% rotatable therein. -With such connection,

t e operating tip 2 ill be securely held in the barrel 1 althoug thegrooves 9 and '10 are notin exactly-op ite relation, andalso' the connection'will orni suitable frictional engagement between the said operating tip and arrel to. prevent free or loose rotation between the same if the grooves 9 and 10 are shghtly shifted from the exactly opposite relation, but the same are easily detachable from each other, so that the lead propelling meichanism may be withdrawn from the bar-- re I Insertible within'the barrel 1 from its fore 7 end are a stationary tubular guide bush 12 and a rotatable'tubular guide bush 13, the

. latter being ofa length shorter than the former, each of which isprovided with a longitudinal guide slot '14 and 15 extending throughout its length respectivel The guide slot 14 is slightly flared at eit er end and the guide slot 15'is slightlyflared at the rear end to accommodate transit of the guide members which will be described hereinafter.

cut round as shown in 16, while the opposite corner is made angular as clearly shown in Figs. 1 and 3, in order to permit free transit of the guide member on the rear edge of the guide bush 12 over the corner upon getting out from the slot, whereon the guide membermay travel round, while the opposite angular corner prevents the 'guide'member from getting outof the. slot and directs the same toward the slot upon entering thereinto, for s5 purposes described hereinafter. The stationary guide bush. 12 is formed with a tongue 17 at its fore part and in substantially opposite position to the slot '14, which is cut therein and bent slightly outward to engage with a longitudinal groove 18 formed in the fore end of the barrel 1, whereby the said guide bush is secured in place within the said barrel as clearly shown Figs. 2, and 3.

Within the barrel 1 is a lead propelling 9 mechanism composed of a propelling tube 19, a leadcarrier 20 and a lead rojector 21. The propelling tube 19 is formed with a spiral slot 22 of course pitch and is inserted in the barrel 1 extending through the guide bushes 12 and 13 and isscrewed in the operating tip 2 at the fore end. Said propelling tube is loosely held in the guide bush 13, while thelatter is tightl but rotatably held in the scribed hereinafter. A plug barrel 1, so that t e propelling tube may. rotated independently in the guide bush grip and hold I the lead ,4,

be p and also maybe rotated in the barrel together with the latter upon their operative engagement as hereina fter described. The pitch' of the said spiralslot isconsiderably rewith a laterally projecting pin or guide spiral slot 20 o member 25 ada ted toextend through the the propelling tube 19' and the guide slot 14 of the stationaryguide bush 12 or the guide-slot 15 of the rotatable guide bush 13, and a longitudinal slot 26 of a length greater than one pitch length of the upper portion of the spiral slot 22 for recelvmg 9.

- 21, particulars of which are described hereinafter. Theprojecting pin 25 may be formed in the lead carrier 20' in such a manner that a stripis formed by longitudinally cutting the rear endot the same up to a point where the pin is to be located to form the slot 26 and is cut to the-necessary length and is bent outwardly at substantially right angles. c

Within thelead carrier 20 is the lead ejector 21 havin a bent extremity 27 which exthe slot 26 oi? the said lead carrier, the spiral slot 220i the propelling tube 19 and the guide slot 14 of the guide bush 12 or the guide slot 15 ofthe guide bush 13, andis located at a'point alined with the pin 25 of the-said lead carrier and spaced one pitch distance therefroms I a It is .to-be-noted that when the guide slots 14 and -15 are once aligned with each other they will be .kept in alignment as the guide bushes 12 and 13 are normally rotated.

' ther rotation of the operating tip 2 after both the pin25 of the lead carrier 20 and the bent extremity 27 of the'lead ejector 21 have come into the groove 15 of the guide bush 13, will cause the guide bush 13 to be rotated to move the slot 15 from the alignment with the slots 14. But, in the reverse rotation of the operwill be rotated after the bent extremity 27 has come into contact with the edge of the end of the guide bush 12 although it is not rotated until that time. 13y this rotation, as soon as the slot 15 has cometo an alignment withthe slot 14 the bent extremity 27 will eome-into the slot 14, whereby the alignment of the slots is resumed.

The space tube 19 carrier bent extremity of the lead -ejector nis'rnwill rotate in umty with the rotatable lead ejector 21 will come in the 13 before the guide bush in order to prevent the- 28- in the barrel 1 between the propelling tube 19 and the eraser holder 6 forms a magazine within' which may be carried extra leads for use with the point of the operating tip.

In operation,"the lead 4 is inserted through the end opening 3 in the operating ti 2 and is held in place by the spht end of e lead carrier 20. To project the .lead from the barrel, the operating tip 2 is rotated relatively to the barrel 1 in a direction to advance the lead carrier 20 through means of the propelling tube 19. In order to ,protect the tip of the lead when the pencil is not in use, the lead may be withdrawn in the barrel byrotating the operating tip relatively to the barrel in the reverse direction. The leadejector 21 will longitudinally niove with the lead elling tube 19 it will advance relatiyely to the lead carrier to eject the lead therefrom, as the 'pitch of-the spiral slotf22 is reduced in that part of the propelling tube as afore- 20, and at the fore part of the promentioned. When .the operating tip 2 isfurther rotated relatively to the barrel 1 after the lead carrier 20 has reached the extremity of its advance the propelling mechabush 13 relatively. to the barrel 1 the pin 25 of said lead carrier being now in the guide 1 slot 15 of said rotatable bush, toprevent the same from being'subjected to undue stress. It shall be noted in the above described arrangement that the bent extremity 27 of the 15 of the guide bush is caused to rotate, bent extremity from engaging with rear edge of the guide bush. On the other hand, when the operating tip -2 is further rotatedrelatively to thebarrel 1 after the lead carrier 23 has reached'the'extremity of its withdrawal the pin 25 of the lead carrier 20 will get on the rear edge of the stationary guide bush 12 over the round corner-16, whereon the said Y pin may slide'a'round, and then the propelling mechanism will rotate in unity relatively to the barrel 1 to prevent the same or the lead from being subjected to-such'undue stress as to cause breakage thereof. It is a special feature of the invention that the breakage of the propelling mechanism or the lead due to excessive rotation of the operating tip relatively to the barrel is entire y prevented as seen from the above description Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claimis:

1. In a pencil, the combination with a barrel and an operating tip connected-thereto, of a rotatable guide bush having a longitudi- 'nal slot, a stationary guide bush having a the rear end and a lead propelling mechaguide slot,

nism composed of a prbpelling'Qtube, a lead carrier and a lead ejector, and the operating tip being arranged to further rotate in safety beyond the extremities of the advance or the withdrawal of the lead carrier.

2. In a pencil, the combination as set forth in claim 1, characterized by the operating tip being securely but-detachably connected with the barrel through means of the provision in the tip of an U-shaped annular groove and the provision in the barrel of a substantially similarly shaped annular groove and a spring ring interposed in these grooves, so that the propelling mechanism may be removed from the barrel with the operating tip as a unit in order to facilitate repairs and the like.

3. In a pencil, the combination as set forth in claim 1, wherein means is provided for securing the stationary guide bush to the barrel, including the provision in a barrel of a longitudinal groove and a tongue struck out from the bush and engaged in the groove of the barrel.

4:. In a pencil, the combination with a barrel and an operating tip detachably and rotatably connected thereto, of a rotatable guide bush tightly arranged Within the barrel and having a longitudinal slot, a stationary guide bush arranged within the barrel and also provided with a longitudinal slot and with a corner at the inner end rounded, and a lead propelling mechanism constructed as a unit with a tip and comprising a propelling tube detachably connected to the inner end of the tip and loosely arraugedwithin the bushes and provided with a spiral slot, the pitch of which is considerably reduced adjacent the operating tip, a tubular lead carrier arranged within the propelling tube having a slot provided with a rib arranged at the inner end of the longitudinal slot and also engaged with the'spiral slot, and a lead ejector arranged within the tubular carrier and having the inner end bent angularly and arranged through the slot in the tube carrier and engaged with the spiral slot in the propelling tube, substantially as and for the purposes set forth.

' In testim'ony whereof I'aflix my signature.

TADAO YOSHIMATSU.

Images