US2198384A

US2198384A - Propelling pencil with lead sharpening means

Info

Publication number: US2198384A
Application number: US271584A
Authority: US
Inventors: Hammer-Purgstall Arthur
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-05-17
Filing date: 1939-05-03
Publication date: 1940-04-23
Anticipated expiration: 1957-04-23

Description

' 1940. A. HAMMERPURGSTALIL 2,198,384

FROPELLING PENCIL WITH LEAD SHARPENING MEANS Filed may 3, 1959 hnten le d that rar

weasel Arthur iiainmer-Purzstall, Vienna, Germany Application May a 19st, Serial No. arises In Germany May 17, 1938,

is on. (oi. lac-1 5) This invention relates to a propelling pencil which is provided in a known manner with a lead sharpening device which is capable of being brought into the operative position. This sharpening device which is suitably arranged in the tip of the propelling pencil enables the lead to be resharpened with the aid of the propelling device provided for feeding the lead forward, which propelling device is actuated, as usual, by means or a rotatable knob at the rear end of the penoil.

It has already been proposed in such arrangements to reduce the rate of forward'feed-ofthe lead during the sharpening operation to the amount which will enable a uniform removal of material during sharpening. The invention also" relates to such an arrangement for regulating the forward feed during sharpening and applies to the type of propelling pencilshaving a lead carrier (insertion sleeve for the lead) which, when turned, is propelled forward by engaging in a feed member having a screw-like action (for instance a helical spring). I

The essential feature characterizing the invention consists in this, that the feed member is held during: writins by a friction coupling, the closiny force or which is produced by a spring which during sharpening allows the coupling to be eased by the axial resistance or the sharpen inc blades (sharpening pressure) acting against the lead and consequently the lead to be turned without or with a greatly reduced forward feed, the spring at the same time itself determining the sharpening pressure.

Now, although through the spring which effects the frictional engagement of the coupling an automatic regulation of the forward feed of the lead during sharpening is provided, the regulating arrangement does not allow at any change (preadjustment) or the initial stressin of the spring, such as is of great advantagefor compensating the fatigue of the spring, for adapting the sharpening pressure to the harm oess of the leads used at any time and for altering it necessary the sharpening pressure to allow forthe considerable increase in the sharpening resistance towards theend oi. the sharpening operation.

The invention also provides a remedy here, a further feature being that the spring which regulates the application pressure of the'friction :ou'pling'is held between the movable part of the :ouplinz' and an adjustabiemembe'r which allows )f the length oi the spring and. consequently the nitial stressing of the spriha'bclng altered.

The arrangement according to the invention permits or an extremely fine automatic regulation of the forward feed of the lead during sharpening, the pressure regulating spring which controls the frictional engagement and determines 5 the magnitude or the closingiorce of the coupling enabling .the sharpening pressure to be accurately adjusted.

Further features or the invention relate to constructional details of the aforesaid coupling or of individual members thereof, to the construction of an arrangement for adjusting the initial stressingof the spring and to an arrangement for securing the lead when the pencil is in normal use.

A constructional example of the propelling pencil according to the invention is illustrated in the accompanying drawinnin which Fig. 1 shows a. longitudinal section through the propelling pencil, Fig. 2 a cross-section on line 2-2 of Fig. l, Fla. 3 the forward part of the propelling pencil (the tip) with the sharpening device in the open atlve position and Fig. t a constructional example oi an arrangemerit for holdinc the lead, while the propelling pencil is in normal use.

in the drawing i is the case of the propelling pencil. preferably made oi an artificial pressed material or the hire, which is provided with a 3) central bore for the lead propelling arrangement of the usual construction. This arrangement consists substantially of. the actual lead carrier 2 which is slidahle in a long sleeved. The lead carrier 2 which is also sleeve-shaped and receives one end of the lead has near its rear end two pins which extend through a longitudinal slot 6 of the sleeve into the space between the sleeve 23 and the outer sleeve i. In this space is disposed an element which acts in the manner of a thread, for instance a fairly strong helical spring 3, and is fixed at its ends to the outer sleeve, as indicated in the drawing at 9 and 9 and between the convolutions of which the pins provided on the lead carrier 5! engage. The

sleeve l is held by frictional engagement with respect to the case i. This frictional engagement is produced according to the invention by a cone coupling, one part, will, of which is arranged on a bush ii screwed into the casing and the other 5 part, l2, of which is arranged on the sleeve 1. The applicationpressure between the parts an and it. required for securing the sleeve 7, when the propelling pencil is in normal use, is produced a helical spring it which, in the exgreases,

ample shown, embraces the long sleeve 3 and is gripped between a part of the rotatable knob it and a collar 3 on the sleeve 3. The collar '3 transmits the pressure of the spring iii to the sleeve 7 and thereby to the coupling part it.

The forward feed of the lead is efiectedin the usual manner by actuating the rotatable knob it provided at the rear end of the propelling pencil. The rotary motion of the knob it is transmitted by the pin i5 to the long sleeve 3, by the latter through the intermediary of the longitudinal slot 6 to the pins 5 of the lead carrier 2 and thereby to the lead carrier itself. During the rotary motion of the lead carrier 2 the pins 5 are moved along the convolutions of the helical spring't, resulting in the leadcarrier being displaced forwards and backwards in accordance with the sense of rotation of the knob it.

In the forward, preferably unscrewable part 16 a sharpening device is contained, which in the illustrated example is formed by a plurality of sharpeningblades i8 fixed to a ring i l. For enabling the sharpening device to be moved out of the inoperative position shown in Fig. 1 into the sharpening position shown inFig. 3, the ring it is provided with a push knob it whichis guided in'a slot 26 of the part it.

For sharpening the lead, the lead is first retracted from the writing position shown in Fig. 1 bysuitably turning the. knob i'4,'at least into the position shown in Fig. 3. Thereupon the sharpening device is brought into the operative position by actuating the push knob iii. The sharpening itself is effected by turning the knob M in the sense corresponding to the expulsion of the lead't. The lead t will'now find an axial resistance against the sharpening blades, which is transmitted by way of the lead or the pins 5 of the lead carrier 2 to the sleeve i. When this axial resistance exceeds a certain amount which the lead i can then turn substantially in a sta-' tionary position, until, through a suitable amount of material being removed at the lead point, the

v axial resistance caused by the sharpening blades has again decreased to acorresponding amount.

-The strength of the spring i3 which in this case acts as, a pressure regulating spring thus determines the amount of axial resistance allowed, that is to say the amount of the application pressure of the lead against the sharpening blades (the sharpening pressure).

After the sharpening operation hasbeen cornpleted, the sharpening device ii, it is returned into its position shown in Fig. l and'thei lead i is then pushed out through the opening it in the part l6.

In the constructional example shown in Fig. 1 the spring 63 is gripped, for the purpose to be explained later, between a. collar 3' of the sleeve 3 and the flange of a bush 26 which is slidable on the sleeve 3. This bush which is provided with a longitudinal slot for the engagement of the coupling pin iii is provided at its free end with an internal thread, in which a threaded spindle 22 engages, which is capable of turning freely, in the rotatable knob iii, The threaded spindle which bears with the collar 23 against the rotatable kno'b carries outside the rotatable imob a ered from the description above.

member for the convenient actuation of the ad'- justingdevice formed by the bush 2i and the spindle, for instance a ringfifi, a knurled head or the like. bush 2| and the spindle 22 may of course be arranged in the reverse way, namely in such a mannerthat an outer thread of thebush 2i coac'ts with the internal thread oia tubular extension ofthe spindle 22.

By, turning the spindle 22 it is possible toad- J'u'st the distance between the seatsof the spring 53 and thereby the initial stressing of thesam'e. This makes it possible to compensate for the re-- sults of fatigue phenomena usually occurring in the case ofsprings and thus to ensure a proper action of the friction coupling, even after the,

propelling pencil has been in use for along time. Furthermore, by a suitable alteration oi the stressing of the spring it is possible to adapt the regulating arrangement to the hardness of the leads at any time in use. It has been found, that harder leads require a stronger application pressure of the coupling than softer leads. It is also possible by means of the adjusting arrangement according to the invention to makecarrier and consequently the latter itself together with the lead are supported resiliently in the propelling pencil in such a manner that, when too heavy a pressure is exerted during writing, the lead may be pushed back into the tip of the pencil. This may be inconvenient during writing Provision is therefore made, through a further modification of the propelling pencil for prevent ing the lead during the normal use of the pro pelling pencil, that is during writing, becoming displaced through too heavy pressure being exerted. According to the invention this is effected by locking means which are, capable of being brought into operation and which act'onthe guiding members of the lead carrier, which are resiliently supported in the case, and fix the said guiding'means with the lead carrier and the lead during writing. Such locking means are shown byway of example in Fig. 4. They consist of a ring Sit which is resiliently supported in the case and which acts against an abutment ti on the forward end of the sleeve i and can be brought by a push knob 32 out of engagement with the abutment 3i. When the locking ring 30 is in the position shown in Fig. 4, it secures the sleeve 7 in position, that is to say it prevents the sleeve which bears against the case through the intermediary of the pressureequalising spring it from becoming displaced in the sense of'the arrow 12 through the writing pressure on the lead While the lead is being'sharpened, the locking means must be put out of operation, as the resilient support must be effective, as will be gath- According to a further feature of the invention the locking means are therefore so arranged that they are controlled by. the actuating members for bring-- ing the sharpening device into the operative po- The screw engagement between the siti'on, this control being such that the locking rs means are operative when the sharpening device is out of operation and vice versa. in the constructional example shown in Fig. i the locking ring 30 is for this purpose connected resiliently with the supporting ring I! of the sharpenilri 2, blades Hi, the actuating knob 32 for the locking, means at the same time-fanning the push knob for moving the sharpening device into and out of the operative position. When the sharpening device is to be moved into the operative position, the locking means must first be released by depressing the knob 32. This releases the locking ring 30 from engagement with the abutment 3| of the sleeve 1. The knob 32 and with it the sharpening device l'l, it can then be pushed forward into the sharpening position. When .the sharpening operation has been completed,

the knob 32 is pushed back again,.until the looking ring 30 snaps in behind the abutment ill.

The sharpening device will at the same time and a spring for determining the closing tonne of the friction coupling.

2. A propelling pencil comprising a lead sharp ening device capable of being brought into and out oithe operative position, a displaceable lead carrier, a feed element constituted by a sleeve containing a helical spring capable of coasting with the lead carrier for producing the forward feed of the lead carrier owing to its rotary motion, a friction coupling provided between the feed element and the pencil case, and a spring for determining the closing force or" the friction coupling.

3. A propelling pencil comprising a lead sharpv Cillllfl device capable oi being brought into and out of the operative position. a displaceablc load carrier. :1. ccrcw-thread-lilte feed clement capable of coactlng with the lead carrier, for producing the forward feed oi the lead carrier owing to, its rotary motion, a cone friction coupling pro vided between the feed element and thepencil case and aspring for determining the closing force of the friction coupling. I

4. A propelling pencil comprising a rotary knob, a lead sharpening device capable of. being brought into andout of the operative'position, a displaceable lead carrier, 9. screw-threaddilre feed element capable of coacting'wlth the lead carrier for producing the forward feed of the lead car rier owing to its rotary motion, a friction coupling disposed between the feed element and the pencil case, a pressure-regulating spring for deterinining the closing force of the sa d coupling, which springi's gripped between the feed element and the end surface of the rotary knob or". the pencil.

5. A propelling pencil comprising a rotary knob, a lead sharpening device capable of being brought into and out of the operative position, a d"- placeable lead carrier, a screw-thread-lilre feed element capable of coacting with the lead carrier for producing the forward feed of the lead carrier owing to its rotary motion, a friction coupling disposed between the feed element and the pencil case, a pressureoeguiatlne spring for determini ng the closing force of the said coupling, which spring is gripped between the movable coupling part and the end surface of the rotary knob of the pencil.

6. A propelling pencil comprising-a lead sharpening device capable of being brought into and out of the operative position, a displaceable' lead carrier, a screw-thread-liire feed element capable of coacting with the lead carrier for producing the forward feed of the lead carrierowing to its rotary motion, a friction coupling disposed between the feed element and the pencil case, a spring for determining the closing force of the said coupling, an adjustable member which enables, the initial stressing oi the spring to be varied, the said spring being gripped between the feed element and the said adjustable member.

7. A propelling pencil comprising-a lead sharpening device capable oi being brought into and out oi the operative position, a displaceabie lead carrier, a screw-thread-like feed element cap able of coacting with the lead carrier for producing the forward feed of the lead carrier owing to its rotary motion, a friction coupling disposed between the feed element and the pencil case, a spring for determining the closing force of the said coupling, an adjustable member which enables the initial stressing of the spring to be varied, the said spring being gripped between the movable coupling part and the said adjustable member.

8. ll. propelling pencil comprising a lead sharpening device capable of being brought into and out of the operative position, a displaceable lead of meeting with the lead carrier for producing theforwarcl feed of the lead carrier owing to its rotary motion, a frictioncoupling'disposed between the feed element and the pencil case s. spring for determining the closing force oi the said coupling, an adjustable member which enables the l'initial stressing of the spring to be varied, the said sprint; being gripped between the feed element andthc said adjustable member,

the adjustable member having the form or a bush which capable oi sliding in the case and oi being actuated from the outside.

ll. propelling pencil comprising a lead sharp oping device capable oi being brought into and outer the operative position, a displaceabie lead carrier, a screw-thread libe feed element capable ofcoacting with the lead carrier for producing the forward flood or the lead carrier owing to its rotary motion, a friction coupling disposed lootween the feed element and the pencil case, a spring for determining the closing iorce oi the said coupling, an adjustable member which enables, the initial stressing oi the spring to be varied, the said spring being gripped between the movable coupling part and the said adjustable member, the adjustable member having the form oi? a bush which is capable of sliding in the caseand of being actuated from the outside.

it. A propelling pencil comprising a lead sharpening device capable of being brought into and out of the operative position, a displaceable lead earlier, a screw-thread-lilre feed element capable oi coasting with the lead carrier for producing the forward feed or" the leadcarricr owing to its rotary motion, a friction coupling disposed between the feed element and the pencil case. a

carrier, a screw-thread-lilre feed element capable Ill spring for determining the closing force of the said coupling, an adjustable member which euables the initial stressing oi the spring to be imasses varied, the said spring being gripped between the teed element and the said adjustable menther, a spindle which is capable of being actuated from the outside and bears against the rotary 5 knob and a screw drive provided between the adjustable member and the spindle.

11. A propelling pencil comprising a lead sharpening device capable of being brought into and out of the operative position, adisplaceable lead 10 carrier, a screw-thizeaddike feed element cap able of coactlng with the lead carrier for producing the forward feed of the lead carrier owing to its rotary motion, a friction coupling disposed between the feed element and thepencil 25 sharpening device capable of. being brought into and out of the operative position, a displaceable lead carrier, a sorew-thread-like feed element cable of coacting with the lead carrier for protiming the forward feed of the lead carrier owing 30 to its rotary motion, a friction coupling provided betweenthe feed element and the pencil case, a spring for determining the closing force of the friction coupling and locking means capable of being put into operation from the outside and ofv acting on the guiding means of the lead car- I rier, which is resiliently supported in they pencil case, and oi fixing the said guiding m'eans together with the lead carrier and the lead during writing.

' 13. A propelling pencil comprising a lead sharp- 11 ening device capable of being brought into and out of the operative position, a displaceable lead carrier, 9, screw-thread-like feed element capable of coacting with the lead carrier for producing the forward feed of the lead carrier owing to its ll rotary motion, a frictioncoupling provided between the ieed element and the pencil case, a. spring for determining the closing force of the friction coupling, locking means capable of being put into operation from the outside and of acting 5! on the guiding means of the lead carrier, which is resiliently supported in the pencil ease, and of fixing the said guiding means together with the lead carrier and the lead during writing and means for enabling, the locking means to be El controlled in dependence on the actuating members for bringing the lead sharpening device into and out of the operative position.