US2311906A - Lead pencil - Google Patents

Description

Feb. 23, 1943- A. LEISTENSQHNEIDER LEAD PENCIL Filed Jan. 9, 1941 2 Sheets-Sheet 1 un/ @wzgg g J HIIIIIIIMW @QQ J A 1 4 m 2 a j 9 QM .Q 4, a

I Feb. 23, 1943'.

A. LEISTENSCHNEIDER LEAD mwn.

' Filed Jan. 9, 1941 2 Sheets-Sheet 2 rlllfllflldllt I ll'llflllfllli Zia/a itiaiS I!!! llllllv \khv Patented Feb. 23, 1943 LEAD PENCIL August Leistenschneider, Dusseldorf, Germany;- ves'ted in the Alien Property Custodian I Application January 9,-1941, Serial No. 373,813 Germany January 27, 1937 g 9 Claims. (CL 120-17) Object-of the invention is a new type of a mechanical or magazine lead pencil wherein the feeding of the lead is operated by means of pressure applied to the cap which results in opening and closing special members holding the lead in the front part of the point end of the pencil casing. It has already been suggested to use for feeding and holding the lead a slit case consisting of several longitudinal parts the cheeks of which may be opened or closed according to the position of a. ring slipped over the case. The movement of 'theclamping ring and the opening and closing of the clamping-case (clamping tongs) is operated by the forward movement of projections or shoulders which may be arranged at the propelling-tube containing the lead, at the lead guiding tube or the inner wall of the pencil casing.-

The hitherto known ways of carrying outlead pencils of this type always provided for a distance of several millimeters between the spot where the lead was clamped upon and the-furthermost end of the point.

A small remnant of a lead could easily be hemmed in by tilting in this interspace-inside the point casing. Furthermore there existed the possibility that the lead would break in the pointchamber between the point and the clamping tongs. It was also impossible to completely use up the last remaining piece of the lead. Moreover there remained between the end of one lead and the front part of the next one an intermediate space which caused the remnant toglide back during use of the pencil. To avoid these disadvantages and furthermore improve the holding and stability of the lead inits clamped position by displacing the clamping tongs further to the front this invention so the pencil) thereby making the fullest use of the requiredto remove or set free the clamping tongs from the clamping ring. v

The forward movement of the clamping tongs placed at the front part of the lead guiding tube is operated by a rearwardly arranged transporting or taking along or coupling device acting similar to a cam between the propelling member and the lead-guiding tube, which device is set out of operation during the forwardly movement after the clamping tongs has been drawn out of the clamping ring. 7

The clamping tongs can now spread open and release the lead, the propelling member together with the point 5 advancing further for approximately 2 mm. without carrying the clamping tongs along with it, while the lead, however, is

' pulled out of the clamping case to a corresponding length. g I g 7 After pressure upon the pencil cap has ceased the propelling tube and the point are both moved rearwardly under spring action and are atthe same time pulling back, by means of the above mentioned transport device, the clamping tongs until these have been pulled back into the -clamp-' ing ring to cause a certain amount. of adhesion over the lead held by the clamping case, and has therebycaused the lead to project partly from the point.

The accompanying drawings show different ways of materializing the invention.

' Figures 1, 2, 3 and 4 show a'lead pencil according to the invention in longitudinal section.

Figure 5 is a section along line}AB in Figure 1.

i Figures 6, 7 and 8 show different modifications oi the transport device. a I

In Figures 1 and 2 l indicates the outer casing of the pencil, and 2 the cap movably arranged thereon. The magazine casing 3 is rigidly fastened to the cap, the tube-shaped lead-propelling member 4 being connected tothe magazine casing. n

The propelling member, which is led through the clamping ring I8, and the point 5 are for instance screwed together so as to move the point forwardly and rearwardly along with said propelling member. The forward movement of the propelling member is limited by the engagement 'of a shoulder 6 in the magazine casing and the projecting shoulder 1, while its rearward motion is limited by the hemming in or clamping of the tongs) clamping tongs in the clamping ring. The return movement of the propelling member 4 is caused by a spring II] which is preferably bearing against the flange II arranged around the propelling tube 4.

Within the propelling tube 4 is arranged a longitudinally displaceable lead guiding tube I2 which is operated by a transport device that may be formed for instance by an offset I3 projecting in an inward direction from the propelling tube 4 and a cooperating offset I4 arranged on the outside of the lead guiding tube.

To bring about a special elastic effect the offsets I3 and I4 may be provided with slots I5.

The end of the lead guiding tube I2 toward the point 5 comprises the clamping case (clamping I6. The latter is provided with longitudinal slots to provide several jaws I1 for bolding and clamping the leads. The clamping of the jaws II upon the lead is effected by means of a clamping ring IB which has a clamping surface I9 conically tapered toward the point, this surface contacting with the outer surfaces 20 of the jaws I'I shaped correspondingly 'conical. If so desired the clamping surfaces may be shortened and it may also be sufiicient to arrange them at the clamping tongs only. The clamping ring may or may not be rigidly connected with the pencil casing I and be provided with openings 2I through which the arms 22 of the propelling tube may pass. 1

The front parts or clamping parts of the clamping ring may be so arranged as to allow for jointed, reeling or perpendicular movement vertically to the ring axis, thereby making the position of the ring adaptable to movements of the clamping tongs diverting from axial movements, i. e., to make the ring self-centering.

The operative movement of the lead guiding tube is limited by a shoulder 23 on the lead guiding tube and a shoulder 24 on the recess in the rearward casing of the clamping ring, while opposite or inoperative movement of the lead guiding tube is limited by the conical surfaces of the clamping case engaging the clamping surface I9 of the clamping ring. Furthermore the lead guiding tube is provided with an auxiliary shoulder 25 which limits the inoperative movement of the lead guiding tube by engagement with the magazine bottom 26. This auxiliary shoulder 25 is only to come into operation when there is no lead in the clamping tongs and when therefore the clamping effect of the clamping surfaces I9, 20 would be non-existent or insuflicient.

The operative movements of all parts, that is propelling operation of the mechanical or magazine lead pencil described takes place as follows:

Pressure is applied to cap 2 and thereby the propelling tube is pushed forwardly (toward the bottom of the accompanying drawings).

Point 5 is thereby also moved forwardly.

At the same time also the lead guiding tube is moved forwardly a short way by means of the spring offset I3 operating upon the offset I4 until the shoulder 23 contacts the shoulder 24 of the clamping ring. Thereby the forward end of the clamping tongs (according to Figure 2) is moved out of the clamping ring I8 to permit the clamping tongs IT to spread apart.

The forward movement of the propelling tube 4 together with the point 5 is continued. If the point channel is still empty of lead the first released lead moves downwardly to the bottom of the point chamber and enters the lead channel of the latter when the point glides back. If a lead .point channel, i.

means of the cooperating offsets had already entered the point channel it is car-' ried along by the light braking pressure of the e., the lead is pulled out of the clamping tongs. After pressure upon cap 2 ceases, the spring ID at first pulls back the propelling tube together with.the point 5. At the same time the lead guiding tube I2 as well as the clamping case H are at once drawn upwardly by I3, I4 until the conical surfaces 20 of the clamping tongs have again been pressed to a limited extent against the clamping surface I9 of the clamping ring I8, thereby holding the lead. The upward movement of the propelling tube together with the point 5 is still continuing while the lead channel 21 of the point is simultaneously gliding over the lead which is held by the clamping device, at the same time permitting a length of the lead sufilcient for writing to project out of the point.

At this further upward movement the offset I3 is moved over the offset I4 of the lead guiding tube I2 so as to return to its former position ready for its next downward movement. The upward movement of the propelling member 4 and the point 5 continues until the tongs have been drawntightly into the clamping. member thereby stop ing further rearward movement. In the exam! ple contained in the drawings this stop is brought about by the outer end surface of the clamping tongs engaging the correspondingly shaped bottom of the point chamber. of the shoulders 8 and 9 a narrow interspace is left when they are brought to their final position.

In Figures 3 and 4 the reference characters are applied to parts constructed and operating in the same or essentially the same way as in the form previously described; in the modified form the clamping tongs II project into the point channel 21 when in writing position and preferably extend a short length beyond the free end of the point. During forward movement the same operations take place as described with regard to Figures 1 and 2. In the forward point-chamber, however, there are arranged one or several springs 28 connected to the point.

Springs 28 are provided in the point 5 to operate upon the tongs parts I! and hold the tongs together even after the conical tongs surfaces 20 have been detached from the clamping surface I! of the clamping ring I8.

After shoulder 23 has engaged shoulder 24, the spring ends 28 move with the point 5 over the tongs I1 and release the latter as well as the lead.

At the same time the spring ends 28 close slightly in a springy way and thereby take over the functions of the lead channel of Figuresl and 2, i. e., they prevent the lead from falling entirely out of the pencil and also serve to pull the lead further out of the tongs.

While the point 5 moves rearwardly the springs 28 are also pulled back and again engage over the tongs.

In the modification shown in Figure 4, the upper end I8 of the clamping ring is formed to engage a supporting shoulder IM and seal in a groove I8b in the part I8c of the clamping ring I8 which is connected with the pencil casing.

In Figure 5 the numerals indicate the same parts as in Figure 1. In Figure 6 the propelling tube 4 in place of the offsets I3, is provided with springs 29, which cooperate by means of their in: wardly bent ends 30 with a fixed projection 3| on the leading guiding tube I2. According to Figure 7 the springs 29 are bent at their ends 32 and co- Between the surfaces operate with the fixed projections 3| of the feeding tube l2.

According to Figure 8 a groove or slot 33 is provided at the propelling tube 4 in which is fitted a. ball 34. This'ball is for instance held by a spring blade 35 fastened to the propelling tube 4 and having a slot or groove 36. The ball 34 in the absence of resistance, compels the movement of the feeding tube while at the same time permitting under resistance the forward and rearward passing of the propelling tube 4 over the projection 31. The balls 34 cooperate with position-determining recesses 31.

The mechanical or magazine lead pencil described offers various advantages, for instance: the release of the clamping tongs takes place at the beginning of the lead movement in the tongs. Thereby repeated grating stress of the lead inside the point channel which tends to damage leads and point channel are avoided.

In the constructions hitherto known, wherein the leads fall forwardly or downwardly to the lead-bottom of the point chamber, the channel has to glide forwardly and backwardly over the lead at every movement and therefore lead dust is easily formed. Lead and point channel are both worn ofi by this repeated rubbing over the lead. The lead dust thus grated off often sticks in the point chamber. All these disadvantages are avoided in the new type of construction.

In the construction according to the present invention the tilting of a short piece of the lead between the bottom of the point chamber and the tongs is practically impossible.

Once the front part of a lead is gripped by the point it is no longer necessary to hold the pencil according to the present invention with its point downwardly for further feeding of the lead.

The point 21 pulls the lead out of the clamping tongs while such tongs are spread apart, so that the feeding of the lead will take place evenly in any position in which the lead pencil may be held.

A further advantage consists in the simplified construction, for all movements are operated solely by means of a single turn spring, while formerly similar constructions required at least two springs. Furthermore the leads may be pushed forward as far as desired without'the necessity of a special auxiliary device; Lastly the arrange-- ment of auxiliary springs 28 ofiers the advantage that no slitting of the point is necessary.

The type of construction described may be altered in different ways and furthermore developed within the scope of the main ideas of this invention.

The invention may be applied to types both with loose and/or solid connection between the tongs parts and the feeding tube.

I claim:

1. A magazine pencil, including an outer casing, a cap slidable in both directions relative to the casing, a pencil point slidable on the casing. a lead-propelling member conneicting the cap and its frictional connection withthe lead propelling member.

2. A construction as defined in claim 1, including means to limit movement of the lead-guiding member short of the full similar movement of the lead-propelling member.

3. A construction as defined in claim 1, wherein the lead-propelling member and lead-guiding member are formed with cooperating offsets to insure their normal frictional connection while permitting their relatively independent movement under movement-resistance of either.

4. A magazine pencil, including an outer casing, a cap movable in both directionsin the easing, a point movable with the cap, a lead clamping 'means, a lead-guiding member carrying a part of the clamping means and frictionally responsive to cap movement, means in the casing to interrupt frictional cooperation of the member at a'point short offull cap movement, the point and cap being connected for simultaneous and similar movement in one direction under manual pressure on the cap, and means on the casing for moving the cap and point in the opposite direction.

5. A magazine pencil, including a casing, a cap movable in both directions in the casing, a. point for the pencil, a lead-propelling member connected to the cap and to the point, a lead-guiding tube frictionally movable by the propelling member, lead-clamping elements carried by the guiding member and arranged within the point, and means to interrupt frictional cooperation between the propelling and guiding member during and prior to the full movement of the propelling member in one direction.

. 6. A construction as defined in claim 5, wherein the guiding member at the upper end is open to the interior of the cap, and wherein the propelling member substantially closes the lower end of the cap surrounding the upper end of the guiding member.

7. A construction as defined in claim 4, wherein the means for moving the cap and point in opposition to their manual movement includes a spring housed in the casing and operating automatically on the release of the manual pressure.

8. A construction as defined in claim 5, including a clamping case for operating the clamping means carried by the guiding member, and means to compel clamping action of the case in movement of the guiding member in one direction.

9. A construction as defined in claim 5, wherein the propelling member is provided with a shoulder to be engaged by' a shoulder on the guiding tube to position such parts for maximum frictional cooperation.

, AUGUST IEIS'IENSCI-INEIDER.

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