US3503693A

US3503693A - Drafting pen

Info

Publication number: US3503693A
Application number: US762844A
Authority: US
Inventors: Edward Bok
Original assignee: DIKE Inc
Current assignee: DIKE Inc
Priority date: 1968-09-26
Filing date: 1968-09-26
Publication date: 1970-03-31
Anticipated expiration: 1987-03-31

Description

March 31, 1970l E. BoK

DRAFTNG PEN Filed Sept. 2, 1968 United States Patent O 3,503,693 QRAFTING PEN Edward Bok, Falls Church, Va., assignor to Dike, Inc., Washington, D.C., a corporation of the District of Columbia Filed Sept. 26, 1968, Ser. No. 762,844 Int. Cl. B43k 1/10 U.S. Cl. 401--259 Claims ABSTRACT 0F THE DISCLOSURE A means for simultaneous ink reservoir Vent-control and control of the movements of the used cleaning wire in stylographic drafting pens.

CROSS REFERENCES TO RELATED APPLICATIONS In drafting pens, Vent valves have been disposed effectively in the upper portion of the ink reservoir as, for example, described in my patent application Ser. No. 697,433, filed Jan. 12, 1968, entitled Drafting Device and application Ser. No. 759,001, filed Sept. 11, 1968, entitled Drafting Pen With Vent Valve.

A related improvement concerns the provision of a knob-operative stem through the interior of the drafting pen ink-reservoir, providing thereby improved cleaning media for the ink passageway in the tip of the drafting pen, all as described in my patent application Ser. No. 758,304, filed Sept. 9, 1968, and entitled Drafting Pen With Extensible Tip; and in my patent applications Ser. No. 760,923, tiled Sept. 19, 1968, entitled Drafting Pen; and Ser. No. 762,878, led Sept. 26, 1968, entitled Drafting Pen.

BACKGROUND OF THE INVENTION Field of the invention Contemporary drafting pens include for the most part a cylindrical hard metal tip and a clearing needle extending from the reservoir axially of the tip. The needle usually has a weight seated in the reservoir, so that a jerking movement of the pen will unseat the weight and actually reciprocate the needle Within the ink-flowing capillary passage which extends from the reservoir through the cylindrical pen tip. This reciprocation of the needle clears the passage of crystallized ink permitting a normal ink flow during drawing. According to such pen structures the clearing needle can be extended or retracted within the cylindrical pen tip to a very small degree only. As a result, it is not possible to completely clear the capillary passage of crystallized ink.

Description of the prior art The prior art devices have included mechanisms for extending and retracting the needle within the pen tip. However, the degree of extension or retraction has been slight and there has not been a positive means for clearing the capillary passage. See Buschle (2,805,645). In this device the crank shaft 6 and guide rod 3 are provided for reciprocating needle A within the pen tip 1. Reciprocation of the needle is limited to the extent of the offset 6 in the crank shaft and there is not provided a positive means for automatically retracting the needle.

See also Cholet (2,878,783). Here needle 23 is simply used as a sealing mechanism and there is not provided any means for longitudinally reciprocating needle 23 within the pen tip to the extent thatcrystallized ink may be completely removed. Also there is not provided any means for automatically withdrawing the needle as it is desired to write.

In the patent application (Ser. No. 697,433), entitled 3,503,693 Patented Mar. 3l, 1970 f. i ICC Drafting Pen and led by applicant herein J an. 12, 1968, a drafting pen is described whereby it is possible to have the drafting pen placed on the sheet at an angle which is most suitable for the draftsman. This pen included the combination of a pen tip and a guide or support which rested on the drafting sheet. Consequently, the pen tip was supported at an angle to the paper and the radial position of the pen tip with respect to the barrel was fixed.

In some drafting Work this more expensive construction is not required, especially if the quality of the drawn lines are of not too great importance. The possibility of supporting a drafting pen in a given radial position and with only the pen tip resting upon the drafting papers provides a big advantage over the existing drafting pens.

Furthermore, conventional stylographic drafting pens and also the drafting pens as are described in the aforementioned patent application (Ser. No. 697,433), make use of a vent construction to the ink cartridge which is positioned in the bottom part of the pen underneath the ink cartridge. See Patent No. 2,891,512. In this type vent there are the disadvantages of an easy clogging with dried ink in the vent opening and the leakage of ink through the opening in the pen tip.

Other vent constructions are illustrated in Patent Nos. 1,319,556 and 1,457,875 describing stylographic fountain pens, which are not suitable for drafting straight lines, since the flow of ink around the pen tip is not tolerated 'when using a ruler.

Patent 3,333,576 has an expensive buildup for a low priced drafting pen, having a pressurized seat for activating a cleansing wire in the absence of any valving for the air vent.

In the drafting pen construction of Y. Wallace (2,214,494) the inner end portion of the pen tip is provided with a large bore 13 and the outer end with a smaller bore joining the larger bore in a conical bevelled portion 15. Here, as the pen is at rest, ink crystallization at the bore ends is likely.

In my copending applications for Patent Ser. No. 759,001, tiled Sept. 11, 1968, entitled Drafting Pen With Vent Valve; Ser. No. 760,923, iled Sept. 19, 1968 and entitled Drafting Pen; and Ser. No. 762,878, liled Sept. 26, 1968, and entitled Drafting Pen, a similar structure is shown and described, but the means facilitating venting and securing of the pen differ materially.

SUMMARY OF THE INVENTION According to the invention, the necessary regulation of air admitted to the drafting pen ink reservoir is controlled by a spring-pressurized stem, which extends in construction through the top of an ink reservoir contained within the pen. Simultaneously, this stem serves to impel a downward thrust to a cleaning wire, to thereby provide a fast and complete cleaning of the ink passageway in the pen tip. Both venting of reservoir and cleaning of the ink passageway are controlled by hand manipulation of a stem connected knob. A pressure spring located in the ink reservoir underneath the pen needle Weight serves to urge the cleaning wire to its rest position inside the pen tip if no manual force is applied to the stem connected knob.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical sectional view of a stylographic drafting pen, according to the invention showing cleaning wire, stem holder and attached knob in rest position;

FIG. 2 is an enlarged fragmentary vertical sectional view of the writing nib of the drafting pen according to FIG. 1;

FIG. 3 shows the Writing nib according to FIG. 2 with cleaning wire' forced downwardly to its lowermost position;

43 FIG. 4 is.the.writing nib according to FIGS. 2 and 3 showing cleaning wire in its uppermost position;

FIG. 5 is an enlarged horizontal sectional view of the holder assembly taken along section lines 5 5 of FIG. 1;

DESCRIPTION OF THE PREFERRED EMBODIMENTS Pen comprises barrel 12, having ink reservoir 14 and the writing nib 16 with the attached pen tip 18. Within, cleaning wire 20 is attached to the needle weight 22 and the reciprocable vent stem 24 is connected in turn to stem holder 26, all as shown in FIG. l. Ink reservoir 14 fits with its bottom 110 in the flat interior 112 of barrel 12. The knob 28 of this stem holder 26 protrudes through the opening 30 in the side wall 32 of the barrel 12, and is manually placeable in slot 30. Other knob constructions with the same function are also possible, as for instance, a knob representing a fixed extension of the stem holder 26, protruding through the top of the barrel 12.

In operation, after initially filling reservoir 14 with ink 78, the writing nib 16 may be secured leak free with its fiat sided nib seat 111 against the bottom part 110` of the ink reservoir 14 (see also FIG. 5) by means of the threaded plug 50 engaging corresponding threads 98 of the barrel 12 and securing this nib in position without rotary angular displacement. Thus, one is given a pen tip 18, having an angular bottom 60 which is at about 30, enabling the drafting pen to be advantageously held at an angle of about 60 with respect to the drafting sheet. Needle weight 22 is longitudinally movable in the interior 60 of writing nib 18, whereby the lock pin 106 prevents the slideable removal of the weight 22 during the disassembling of the pen 10 for filling purposes. (See FIGS. 4 and 5.) In the bottom interior 114 of the writing nib 16 and underneath needle weight 22 the compression spring 116 is located. As is shown in FIGS. 1 and 2 with the knob 20 in its rest position the needle weight 22 rests upon the expanded spring 116 with the bottom 68 of cleaning Wire 20 retracted to the inside 84 of the pen up 1s. (FIG. 3.)

In the interior 80 of the stern holder 26 the pressure spring 72 is located, whereas in the top part 102 the opposed pressure spring 100 is positioned. This combination of springs (FIG. 1) provides a variable compression gap between stem holder 26 and ink reservoir 14, whereby in the rest position of the knob 28 (FIG. l), the valve portion 118 of the vent stem 24 is fitted in the vent-opening 76 of the reservoir 14. Now, as the ink reservoir 14 is filled with ink 78, it is thus prevented from leaking through closed opening 76, the same seal being effective as knob 28 may be brought to its lowest position against shoulder 80, all as indicated by the lower phantom line knob position shown.

Again, in operation, if the stem knob 28 is moved upwards against compression spring 100 from its previous position of rest, to the limiting shoulder 82, stem valve 118 is moved out of its opening 76, providing thereby ventilation of the ink reservoir 14 as may be required periodically.

Bearing in mind the foregoing, as knob 28 is quickly retracted from its lowest position to its top position against shoulder 82, the stem 24 is removed from needle weight 22, leaving the needle weight 22 free to move upwards under the expanding force of pressure spring 116, resulting in a temporarily longitudinal displacement of the cleaning wire over the distance as shown in FIG. 4 with the bottom 68 of the cleaning wire 20` retracted into ink chamber 104 and the Wire 20 surrounded by ink in liquid form. At the same time, this ink iniliquid form can and should leak from this chamber 104 into the ink passage 84. During succeeding forced downward 'movement of the cleaning wire 20 the now wet Wire forces ink in liquid form through the ink passage 84 and easily scrapes and removes dried ink and other foreign matter out of passageway 84.

vAgain, after a long period of non-use, flowing of ink through the ink passage 84 may be achieved by downward displacement of knob 28 to its lowest position at shoulder 80, forcing thereby wire 20 downward to protrusion beyond pen tip 18, `(FIG. 3). This may be followed a few' times by a succeedingupward movement of wire 20 by the urging force of the depressed vpressure spring 116, resulting in a sufficient loosening until it is possible to obtain a longitudinal displacement to the top position of the wire 20 by means of the expanding force of the spring 116 when the stem 24 and associated elements have been quickly and forcibly displaced to the uppermost position represented by FIG. 4.

With this unique construction of the drafting pen 10 no shaking is required to remove dried ink or other obstacles from the ink passage 84.

In the uppermost position 82 of the knob 28, the valve 118 is moved out of the vent opening 76 of the ink reservoir whereby there is no required longitudinal jerking of the drafting pen, with no resultant flowing of the liquid ink 76 in the ink reservoir, avoiding thereby ink leakage through the opening 7-6. Only the stem extension 120 with a smaller diameter as part of vent stem 24 protrudes through the opening 76 into the ink reservoir to contact the needle weight 22. By means of this vent system, ventilation to ink reservoir 14 is possible 'without any downward protrusion of cleaning wire 20 from pen tip 18, thus enabling an uninterrupted drafting of lines during this Venting period.

The pressure springs 72 and 116 may be given such a compression force in their compressed position, and the weight 22 and the stem holder adjusted in weight and the pressure spring can be made so easily compressible, that by manually loosening the knob 28 from its lowest position, the whole combination of cleaning wire 20, needle weight 22, Vent stem 24, stem holder 26 and knob 28 may be automatically forced by the expanding springs to their temporary topmost position. Consequently, Yonly manual downward movements of the knob 28 are then required to clean the ink passage 84. Furthermore, the pressure springs 72 and 116 may be combined into one spring 116 with the achieving of the same described results.

In the drafting of lines, the cleaning wire 20 does not touch the drafting paper, thus no scratching of this paper occurs from scraping movement of this wire 20 over its surface. This yields best drafting results.

I claim:

1. A self-cleaning, ventable writing pen, comprising in combination:

(A) a barrel to which is secured (B) a nib, said nib defining a pen scrib'er channel at its free end; I

(C) a reservoir fixed within the barrel and being communicant with thenib, said reservoir being vented at its upper end; A

(D) a reciprocable valve stem, passing into said'rservoir and having a valular portion thereof engageable with the reservoir, said stem being variably compression seated with respect to the reservoir and having means to dislocate said vstem extensibly with respect to said reservoir;

(E) a cleaning wire extending through sad channel and having weight means at its free end, said weight being alternately compression contacted by said stern for use in cleaning said channel by reciprocable movement thereof;

(F) first compression means connecting vthe reservoir and stem; and

(G) second compression means in opposition to the first, said second compression means engaging the barrel and stern;

(H) third compression means seated in the nib against the weight means, urging the weight means and pen upwardly.

2. The drafting pen according to claim 1 wherein the stem includes successive portions of variant diameters, the lower portion being of lesser diameter than the upper portion, whereby the respective portions alternately vent and seal the reservoir upon manipulation.

3. The drafting pen according to claim 2 in which stern and reservoir are complementally asymetric in at least one contiguous portion thereof to secure pen tip writing end and associated elements against displacement.

4. The pen according to claim 2, in which the nib includes locking means at one end to block movement of said cleaning wire out of said nib.

5. The writing pen according to claim 2 in which the nib channel includes plural chambers, a first chamber being of substantially greater diameter than the pen and a second being slightly greater, the said first being disposed to pass ink as the wire is retracted adjacent same and the second being in extension thereof and adapted to cleaning contact with the pen as it is reciprocated from the rst to the second, precedent to seating in extension of the second in writing.

6. The writing pen according to claim 5 in whirh the nib includes locking means at one end to block movement of said cleaning wire out of said nib.

7. A drafting pen comprising:

(A) a pen barrel;

(B) an ink reservoir of the type having an air vent and supported within said barrel;

(C) a pen nib with a spirng biased and weighted cleaning wire movable in the nib, the nib including a hollow ink capillary passage communicating with said ink reservoir and terminating in a tubular pen point;

(D) a spring pressurized stern, superposed with respect to said reservoir within said barrel and including:

successive portions of variant diameters, one said portion being of lesser diameter than the other said portion, both said portions being engageable with the ink reservoir whereby the respective portions alternately vent and seal the reservoir upon manipulation;

(E) spring bias means engaging the stem exteriorly, said bias means seating on said barrel whereby upon alternate retraction and ejection of said stem, the hollow ink capillary passage will be cleaned, washed and sequentially scraped, precedent to further usage of said pen point.

8. The drafting pen according to claim 7 in which the nib includes locking means at one end to block movement of said weighted cleaning wire out of said nib.

9. The drafting pen according to claim 8 in which the nib channel includes plural chambers, a rst chamber being of substantially greater diameter than the pen and a second being slightly greater, the said rst being disposed to pass ink as the wire is retracted adjacent same and the second being in extension thereof and adapted to cleaning contact with the pen as it is reciprocated from the tirst to the second, precedent to seating in extension of the second in writing.

10. The drafting pen according to claim 9 in which the nib includes locking means at one end to block movement of said cleaning wire out of said nib.

References Cited UNITED STATES PATENTS 1,447,632 3/ 1923 Schmidt 401-258 2,805,645 9/l957 Buschle 401-151 2,878,783 3/1959 Cholet 401--258 2,891,512 6/1959 Kovacs 401-258 X 3,419,335 12/1968 Bok 401--260 X FOREIGN PATENTS 857,986 1/ 1961 Great Britain.

885,345 12/ 1961 Great Britain. 1,073,878 6/ 1967 Great Britain. 1,131,287 10/1956 France.

LAWRENCE CHARLES, Primary Examiner