US3356440A

US3356440A - Marking implement

Info

Publication number: US3356440A
Application number: US458658A
Authority: US
Inventors: Darst Robert John
Original assignee: WA Sheaffer Pen Co
Current assignee: WA Sheaffer Pen Co
Priority date: 1965-05-25
Filing date: 1965-05-25
Publication date: 1967-12-05
Anticipated expiration: 1984-12-05
Also published as: NL6516767A; ES318999A1; GB1073267A; BE671827A; BR6573175D0

Description

R. J. DARST Dec. 5, 1967 Filed May 25, 1965 United States Patent 6 i 3,356,440 MARKING IMPLEMENT Robert John Darst, Fort Madison, Iowa, assignor to W. A. Sheatfer Pen Company, Fort Madison, Iowa, a corporation of Delaware Filed May 25, 1965, Ser. No. 458,658 9 Claims. (Cl. 401-418) ABSTRACT OF THE DISCLOSURE The drawings and specification of this application disclose an improved marking implement having a barrel defining first and second barrel portions, each portion having a capillary fluid reservoir therein. A capillary writing point is carried by the first barrel portion for continuous fluid' transfer contact with the reservoir in the first barrel portion and releasable fluid contact with the reservoir in the second barrel portion. To condition the implement for use, the barrelportions are separated; thereby withdrawing the point from contact with the reservoir in the second barrel portion and exposing the point for writing. Upon reassembly of the barrel portions, the point furnishes a capillary path through which fluid is transferred from the reservoir in the second barrel portion to the reservoir in the first barrel portion; thereby back-flushing the point while substantially equalizing the fluid in the reservoirs. Simultaneous with this transfer of fluid, air passing through an air passage extending between the barrel portions, is drawn from the first to the second reservoir.

This invention relates to an improved marking implement and more particularly to a marking pen having a tip which is maintained in a free flowing, fully moistened, ready-to-mark condition.

The use of marking pens has greatly increased in recent years. With this increased use, there has developed a demand for better instruments having improved operating and marking characteristics. One significant'irnprovement in this area in recent years was the development of the porous plastic tip replacing, as it did in many quality instruments, felt tips which had for many years been standard in marking pens.

In a marking pen, ink is carried to and distributed over a relatively large surface area of the tip by means of a multiplicity of relatively small capillary passages.

Evaporation-ofthe volatile constituents of the ink and drying out of thetip-is thus a major problem in a marking pen, particularly if the pen when not in use is left uncapped for a prolonged period of time. The remaining non-volatile ink constituents tend to temporarily clog the small capillaries and prevent proper flow of ink through the tip from the reservoir at one end thereof to the marking surface at the other.

In marking implementmas in writing implements in general, it is desirable to have as large a capacity ink reservoir as practical in order to avoid frequent replacement or refilling. A large capacity ink reservoir is particularly important in an implement such as a marking pen which is adapted to scribe relatively broad lines requiring a heavy ink lay down. The capacity of an ink reservoir, however, is limited by practical considerations, not the least of which is that of controlling the flow of ink from the reservoir. Such control may be accomplished, for example, by means of a valve or by means of a capillary filler.

The capillary filler has been found to be the least expensive means of controlling the ink flow from the reservoir in a marking pen. In the case of the usual absorbent capillary filler employing a multiplicity of felted fibers, the dimensions of thecapillary spaces will vary widely,

ice

With some of the capillaries being very fine and some being very coarse. Because of this and particularly because of the fine capillaries, some of the ink which is initially charged into the filler will not properly transfer to the tip by capillary action, and, consequently, this ink will not be available for marking. The percentage of this unavailable ink will in general increase with the length of the filler for the ink at those parts of the filler remote from the tip must be transferred to the tip through passageways which are not only long and tortuous but which vary in size and thus do not effect a ready transfer of the ink.

In addition, it has been found that fillers which are relatively long generally cannot be loaded with ink as heavily as the shorter fillers, perhapsbecause the coarser capillaries in the filler will not support an excessive height of fluid in the reservoir- It is, therefore, an object of this invention to provide a marking implement having improved operating and marking characteristics.

It is another object of this invention to provide a marking implement having a tip which is kept in a fully m0istened, ready-to-mark condition.

It is a further object of this invention to provide a marking implement employing a capillary reservoir filler from which ink may be drawn more efficiently and in which the amount of ink available for marking is increased.

It is still a further object of this invention to provide a marking implement having a more eflicient transfer of ink from the capillary reservoir filler to the marking tip.

It is an additional object of this invention to provide a marking implement which will automatically recondition and flush the tip with ink when the implement is capped and the tip is covered for storage.

gagement with the marking tip and is fully vented for marking.

Other objects may be seen and a fuller understanding of the invention may be had by referring to the following .description and claims taken in conjunction with the accompanying drawings.

In accordance with this invention, a marking pen is provided which includes a barrel having two separable sections. These sections being normally assembled in coaxial alignment when the pen is conditioned for storage and being separable to condition the implement for marking. Each of the barrel sections has a capillary fluid reservoir adapted to hold a supply of ink. A capillary marking tip extends between and is in fluid communication with the reservoir elements in the two barrel sections when the barrel sections are assembled to condition the pen for storage. Means is provided for fixedly connecting the tip to one of the barrel sections, this means preferably consisting of an extension of the barrel section. Thus when the barrel sections are separated to condition the implement for marking, the tip will remain aflixed to the one barrel section, and the other end of the tip will be withdrawn from fluid communication with the reservoir of the other of the barrel sections and this tip end will be exposed for marking.

The rearward end of the one barrel section, i.e. the end opposite the tip, is preferably so constructed that the other barrel section may be assembled thereon after it has been initially removed from the tip end to expose the tip and condition the pen for marking. The rearward end of the one barrel section effectively seals the capillary fluid reservoir in the other barrel section from the atmosphere while the pen is in use.

Reference is now made to the drawing wherein:

FIGURE 1 is a longitudinal sectional view of a marking implement constructed in accordance with this invention;

FIG. 2 is an enlarged sectional view of the implement taken substantially along line 22 of FIG. 1;

FIG. 3 is an enlarged sectional view of the implement taken substantially along line 33 of FIG. 1;

FIG. 4 is an enlarged sectional view of the implement taken substantially along line 4-4 of FIG. 1; and

FIG. 5 is a fragmentary sectional view showing the connection between the barrel sections of the implement when the implement is conditioned for marking.

With further reference to drawings and more particularly to FIGURE 1, there is shown a marking implement which is constructed in accordance with this invention. This marking implement includes a barrel consisting of two hollow, elongated, substantially

cylindrical barrel sections

12 and 14.

The barrel section 12 includes a substantially cylindrical body 15 having an internal bore 15a. Integral with the body of the barrel section 12 and extending forwardly therefrom is a tip holder 16 having a bore 16a extending therethrough (see FIG. 3) and the opposite (rearward) end of the body 15 is closed by means of an end cap 17.

The forward end portion 15b of the barrel section body has a reduced external diameter, and thus an annular forwardly facing shoulder 18 is defined on the exterior of the barrel section body immediately adjacent the forward end portion 15b. The tip holder 16 is still further reduced in outside diameter, and it is preferably forwardly tapered from its junction with the forward end portion 15b of the body. The end cap 17 preferably has the same basic reduced external diameter as the forward portion 15b of the body.

A plurality of minute formations such as' the small ridges 19 and grooves 20 (see FIG. 4) on the forward portion 15b of the barrel section body extend from adjacent the shoulder 18 to a point spaced from the tip holder 16, leaving a clear sealing surface 15b on this forward portion 15 immediately adjacent the tip holder. Similar formations such as ridges 21 and grooves 22 on the end cap 17 extend from approximately the rearward end of the barrel section body 15 to a point spaced from the rearward end of the cap 17. The rearward end of the cap is beveled to provide a sealing surface 23. The purpose of the formations and sealing surfaces on the forward end portion 15b and on the end cap 17 will be hereinafter more fully explained.

Mounted Within the bore 16a of the tip holder 16 is a capillary marking tip 24 which is preferably formed of porous plastic in accordance with the teaching of Casey, et al., United States patent application Serial Number 244,196 filed December 12, 1962. 1

One end 24a of the tip extends forwardly of the tip holder 16 and is pointed or otherwise suitably shaped for marking. The opposite end 24b of the tip extends rearwardly into the bore 15a of the barrel section body portion for fluid communication with a supply of ink contained therein.

The diameter of the tip 24 is slightly smaller than the diameter of the bore 16a of the holder 16 in order to permit air to pass into the barrel section 12 along the sides of the tip thereby effectively venting the interior of the barrel section to the atmosphere. The tip 24, however, is held firmly and centrally within the bore 16a of the holder 16 by means of a plurality of formations 25 which extend inwardly from the bore-defining walls of the holder into engagement with the tip. These formations 25 are preferably in the form of longitudinally extending ribs, and there are preferably four such ribs angu- 4 larly spaced from one another, as is best illustrated in FIGURE 3.

Disposed within and substantially filling the bore 15a of the barrel section body portion 15 between the tip holder 16 and the end cap 17 is a capillary reservoir element or filler 26. The filler is in fluid conducting relationship with and preferably at least partly surrounds the inner end 24b of the tip 24. The filler 26 is preferably formed of felted fibers, a large portion of which are oriented in the longitudinal direction. The fibers of the filler provide throughout the filler innumerable capillary spaces and passageways for holding a supply of ink. A suitable filler may be made in accordance with the teaching of United States Patent No. 3,111,702. The capillary filler 26 in the illustrated embodiment is substantially cylindrical in shape except for a channel 27 formed longitudinally in its surface. As will be hereinafter more fully explained, this channel permits rapid charging of the filler with ink and it also provides a passageway for air insuring the desired degree of venting of capillary spaces in the filler.

The barrel section 14 includes a substantially cylindrical body 28 having an internal main bore 29 and a pair of

concentric counterbores

30 and 31. The body 28 is open at one end 32, and it is closed at the opposite end by means of an end cap 33. The first counterbore 30 extends inwardly from the open end 32 of the body to an annular shoulder 34. The second counterbore 31 extends inwardly from the shoulder 34 to a second annular shoulder 35 delimiting one extremity of the main bore 29, and the main bore in turn extends from this second shoulder 35 rearwardly to the end cap 33.

Disposed within and substantially filling the main bore 29 of the barrel section body 28 is a capillary reservoir element or filler 36 having a longitudinal channel 37 formed therein. The filler 36 is preferably formed of felted fibers and identical in all respects to the filler 26 disposed within the barrel section '12, and like filler 26, the filler 36 is adapted to hold a supply of ink within the innumerable capillary spaces and passageways therewithin. Within the main bore 29 of barrel section 14 adjacent the end cap 33 are several longitudinal projections 38 which wedgingly engage and hold the rearward end of the filler 36. An annular washer 40 having a central aperture 40a is snugly and fixedly positioned within the counterbore 31 of the barrel section 14 in firm abutment with the annular shoulder 35. This washer serves to retain the capillary filler in place within the main bore 29 of the barrel section. The washer 40 has a central aperture 40a just large enough to accommodate the forward end of the tip holder 16 of barrel section 12.

In order to permit the pen to be carried in a pocket, a pocket clip 42 may be attached to the end cap 33 of barrel section 14.

The

barrel sections

12 and 14 are adapted to be releasably assembled together in a first coaxial relation illustrated in FIGURE 1 to condition the implement for storage and in a second coaxial relation illustrated in FIGURE 5 to condition the implement for marking.

When the marking implement 10 is assembled for storage as shown in FIGURE 1, the forward end portion 15b and the tip holder 16 of the barrel section 12 extend into the open end 32 of the barrel section 14, and the open end of barrel section 14 abuts the shoulder on the exterior of the barrel section 12.

An important feature of this invention is the relationship between the various parts of the implement when the barrel sections are assembled for storage. In the storage condition the forward marking end 24a of thecapillary tip 24 extends into engagement with and is preferably enveloped by the capillary filler element 36, the engagement being such as to insure maximum fluid conducting communication between the tip and filler element. It will be seen that this engagement of the tip 24 and the filler 36 places the two

filler elements

26 and 36 within the two barrel sections into fluid communication with one another through the capillary tip 24, resulting in a novel and highly advantageous fluid system for the marking implement. In this system, when the degree of ink saturation of the filler element 26 falls below that of the filler element 36, ink will be automatically transferred through the tip 24 from the more saturated element 36 to the less saturated element 26. The filler elements are preferably equal in size and therefore the system insures in effect that the amounts of ink in the elements are maintained substantially equal. Since in marking, ink flows forwardly through the tip 24 from the reservoir element 26, the system will serve primarily to replenish ink to the reservoir element 26 from element 36, with the ink flowing rearwardly through the tip. This rearward flow of ink to replenish the filler 26 results in a reverse flushing of the tip 24 and effectively reconditions and cleans the tip.

To facilitate the free flow of ink through the tip between the reservoir elements when the implement is in a storage condition, there should also be provision for a countercurrent flow of air between the elements. This is accomplished through the tip holder bore 16a surrounding the tip. So that the tip 24 and the tip holder 16 may i be properly positioned at all times for proper fluid conduction and air flow between the tip and filler element 36, the end of the tip holder 16 is preferably disposed within the'aperture 40a of the washer 40.

In the storage condition, the tip 24 and the

reservoir fillers

26 and 36 should be substantially sealed from the atmosphere so that evaporation loss of the volatile constituents of the ink contained therein may be minimized.

It has been found, however, that the seal should not be provided over a substantial length since this would result in a possible momentary increase in the pressure within the two barrel sections when they are assembled and a possible momentary decrease in the pressure within the sections when they are disassembled. Any such rather rapid changes in pressure could upset the capillary balance of the implement and result in over or under feeding of ink to the tip 24. Nevertheless, in order to ef: feet a stable frictional connection between the

barrel sections

12 and 14, it is desirable that these sections frictionally interengage one another over a substantial distance. To accomplish the desired stable frictional connection between the barrel sections, the diameter of the first counterbore 30 of barrel section 14 is so dimen sioned that it will closely circumscribe and tightlyand frictionally engage the ribs 19 on the forward end portion 15b of the body of barrel section 12. It will be noted that this frictional connection does not produce a seal because air is free to bypass the forward end-portion on either side of the ribs 19 and through the grooves 20.

To elfect the desired seal between the barrel sections, the inside diameter of the second counterbore 31 in the barrel section 14 is made approximately the same as the outside diameter of the forward end portion 15b of the body of the barrel section 12. It will be noted, however, that the second counterbore 31 is recessed from the open end of barrel section 14 by the length of the first counterbore 30, which is slightly shorter than the forward end portion 15b of the barrel section 12. Thus when the end 32 of barrel section 14 abuts the shoulder 18, only a very short length of the forward end portion surface 15b will sealingly engage the wall of the counterbore 3 1. v

In like manner when the

barrel sections

12 and 14 are assembled to condition the pen for marking, the end cap 17 of the barrel section 12 will be received within the open end 32 of the barrel section 14, and the end 32 will abut the rearward end of the barrel section body 15 as shown in FIGURE 5. In this position the beveled sealing surface 23 on the end cap 17 will sealingly engage the annular shoulder 34 at the end of the first counterbore 30 within barrel section 14, and the reservoir element 36 will be sealed from the atmosphere. The ridges 21 and 6 grooves 22 on the end cap 17 serve the same purpose as the ridges 1? and grooves 20 on the forward end portion of the barrel section 12, namely to provide a tight frictional fit of the end cap within the first counterbore 30 of the barrel section 14, without themselves effecting a seal to alter the pressure within the barrel section 14.

The implement 10 may be assembled by the manufacturer as follows: The tip 24 is inserted within the bore 16 of the holder to the position illustrated in FIG. 1. The

fillers

26 and 36 are then inserted into the

barrel sections

12 and 14 respectively. Ink is then charged into the barrel sections preferably in an amount to completely saturate the

fillers

26 and 36 therein. The

channels

27 and 37 in the fillers serve to permit the ink to flow readily down the length of the filler to facilitate the charging of ink. After this ink has been charged, the end cap 17 is then placed on the end of the barrel 12 and sealed in place, and the washer 40 is inserted into the open end of barrel section 14 and also fixed in place against the shoulder 35. The

barrel sections

12 and 14 are then assembled as illustrated in FIGURE 1 to condition the pen for storage.

To use the implement, all the user need do is to remove barrel section 12 from barrel section 14 to expose the outer end 24a of the marking tip. The barrel section 14 is then preferably positioned on the reverse end of barrel section 12 to prevent accidental loss of the barrel section 14 and also to seal the reservoir element in that section from the atmosphere to prevent drying out.

As the marker 10 is used, the amount of ink in the reservoir filler 26 will be reduced to a level below that of filler 36 in barrel section 14, and if the marker is inadvertently left uncapped with the tip exposed for a prolonged period, some dry ink residue may accumulate on the forward marking portion 24a of the tip. When the marker is reassembled for storage in the manner illustrated in FIGURE 1, the exposed portion 24a. of the tip is again placed in contact with the filler 36 within barrel section 14. Since the filler 36 will generally contain more ink than the filler 26 at the time of reassembly, some of the ink in filler 36 will pass by capillary action through the tip 24 from the filler 36 to the filler 26. At the same time air to replace this ink will flow from the capillary spaces and passageways in filler 26 along the channel 27 in the filler and through the portions of the tip holder bore 16a surrounding the tip 24 to the filler 36. Thus a portion of the ink which has been used from reservoir element 26 will be replenished from the supply contained in reservoir element 36 and this replenishment of the ink is by means of a reflushing action through the tip 24 which servesto clean and recondition the tip. Each time the barrel sections are reassembled to conditionthe implement for storage as illustrated inFIGURE l, reservoir element 26 will be partially recharged with ink and the tip 24 will be flushed by the ink flowing from the filler 36. The recharging of the filler 26 and the flushing of tip 24 will continue until there is a substantial balance between the ink supplies in each of the

filler elements

26 and 36. When the available ink in both

fillers

26 and 36 has been used, the implement may be discarded.

Because the point 24.is fed from both ends by the

reservoir fillers

26 and 36, this point is kept continually moist with ink. The use of two relatively short fillers in this manner is much more efiicient than the use, of a single long filler element because in the two filler arrangement described herein the ink needs to be drawn by capillary action over only a relatively short distance before reaching the tip, and there is, therefore, less chance for interruption of the ink flow through the random and nonuniform capillary passageways provided by the "felted fibers.

It may be seen that a marking implement constructed in accordance with this invention automatically keeps the tip in a fully moistened ready-to-mark condition. The ink may be drawn from the capillary reservoir filler and transferred to the marking tip much more efliciently and each time the marker is conditioned for storage, the tip is flushed and the reservoir element is recharged.

Although the invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example and that many modifications and changes in various details may be resorted to without departing from the spirit and scope of the invention, as hereinafter claimed.

What is claimed is:

1. A marking implement including an elongate substantially air-tight barrel, a capillary reservoir element in each end of said barrel, a capillary point extending from one of said reservoir elements into releasable contact with the other, said point providing a fluid path extending between and communicating with said reservoir elements to permit the transfer of fluid therebetween and means for transferring air between said reservoir elements, said barrel being separable substantially intermediate said reservoir elements to expose one end of said point for marking.

2. A marking implement including an elongate substantially air-tight barrel, a capillary reservoir element disposed in each end of said barrel, each of said reservoir elements defining a multiplicity of intercommunicating capillary spaces, a point extending from one of said reservoir elements into releasable contact with the other, said point defining throughout its length a multiplicity of interconnected capillary spaces communicating with and providing a fluid path between said reservoir elements and means defining an air passage communicating with the capillary spaces in each of said reservoir elements, said barrel being separable substantially intermediate said reservoir elements to expose one end of said point for marking.

3. A marking implement including an elongate substantially air-tight barrel, a first reservoir element disposed in one end of said barrel, a second reservoir element spaced from said first reservoir element in the other end of said barrel, said reservoir elements being substantially equal in size, each of said reservoir elements defining a multiplicity of intercommunicating capillary spaces, a point mounted within said barrel and provided with an inner end in continuous contact with said first reservoir element and an outer end in releasable contact with said second reservoir element, said point defining a multiplicity of capillary spaces communicating with one another and with said spaces in said reservoir elements, said point providing a fluid path for the transfer of fluid between said reservoir elements and means defining an air passage communicating with the capillary spaces in each of said reservoir elements, said ends of said barrel being separable substantially intermediate said reservoir elements to expose the outer end of said point for marking.

4. A marking implement including a substantially airtight barrel, a capillary reservoir element in each end of said barrel, a point communicating with and providing a fluid path between said reservoir elements, and means definingan air passage between said reservoir elements, said point and said air passage simultaneously permitting the movement of ink and air in opposite directions between said reservoir elements to maintain said elements at substantially equal ink-air percentage levels, said barrel being separable substantially intermediate said reservoir elements to expose said point for writing.

5. A marking implement including a substantially airtight barrel, a reservoir element disposed in each end of said barrel and provided with a multiplicity of intercommunicating capillary spaces, each of said reservoir elements defining a non-capillary air vent extending substantially its entire. length and communicating with said capillary spaces therein, a point contacting said reservoirs and defining a multiplicity of interconnected capillary spaces communicating with and providing a fluid path between said reservoir elements, and means defining a non-capillary air passage between said vents in said reservoirs, said capillary spaces in said point and said air passage simultaneously permitting the movement of ink and air therethrough in opposite directions between said reservoir elements to maintain said elements at substantially equal ink-air percentage levels, said barrel being separable substantially intermediate said reservoir elements to expose one end of said point for writing.

6. A marking implement including a first barrel portion having an apertured end, a capillary point extending through said apertured end, a second barrel portion having an open end sized to envelop said point and sealably engage said first barrel portion adjacent said apertured end to isolate said point and the interior of said barrel portions from the atmosphere, a capillary reservoir element disposed within said first barrel portion in continuous communication with said capillary point, and a capillary reservoir element disposed within said second barrel portion for releasable communication with said point when said barrel portions are sealably secured together and means for transferring air between said capillary reservoir elements.

7. A pocket type marking implement including a first barrel portion having a reduced point section defining an apertured end, a capillary point mounted within said point section and provided with an inner end projecting rearwardly into said first barrel portion and a tip extending forwardly through said apertured end, a second barrel portion having an open end sized to envelop said tip and telescopically and sealably engage said point section to isolate Said point and the interior of said barrel portions from the atmosphere, a first capillary reservoir element disposed within said first barrel portion in continuous feeding communication with said inner end of said point, a second capillary reservoir element disposed within said second barrel portion for releasable feeding communication with said tip whereby both said reservoir elements are in communication with said point when said barrel portions are sealably secured together and means defining an air passage communicating between said capillary reservoir elements independently of the atmosphere.

8. A marking implement including a first barrel portion closed at its rearward end and having a reduced point section defining an apertured forward end, a point mounted within said point section and provided with a multiplicity of interconnected capillary spaces, said point having an inner end extending into said first barrel portion and a Writing tip extending forwardly through said apertured end, a second barrel portion having an open end sized to envelop said tip and telescopically and sealably engage said reduced point section to isolate said point and the interior of said barrel portions from the atmosphere said apertured forward end providing an air passage between the interior of said barrel portions, a first reservoir element disposed within said first barrel portion and provided with a multiplicity of intercommunicating capillary spaces in continuous communication with said air passage and said inner end of said point, a second reservoir element disposed within said second barrel portion and provided with a multiplicity of interconnected capillary spaces in releasable communication with said tip, whereby both said reservoir elements are in communication with said point and with one another through said point and said air passage when said open end of said second barrel portion is sealably secured to said reduced point section, and a reduced rearward end on said first barrel portion, said reduced rearward end being sized for sealable engagement with said open end of said second barrel portion to isolate said second reservoir element from the atmosphere when said marking implement is conditioned for use.

9. A marking implement including a first barrel port on having a reduced point section defining a point-receivmg bore and an air passage coextensive with said bore, a point ted Within said bore and provided with a multiplicity of interconnected capillary spaces, said point having an inner end extending within said first barrel portion and a writing tip extending forwardly through said bore beyond said reduced point section, a second barrel portion having an open end sized to envelop said tip and telescopically and sealably engage said reduced point secton to isolate said point and the interior of said barrel portions from the atmosphere, a first reservoir element disposed within said first barrel portion and provided with a multiplicity of intercommunicating capillary spaces, said first reservoir element surrounding and engaging the inner end of said point to provide continuous communication between the capillary spaces in said reservoir element and the capillary spaces in said point, a second reservoir element disposed within said second barrel portion and provided with a multiplicity of intercommunicating capillary spaces, said second reservoir element being spaced from said open end a distance substantially equal to the length of said reduced point section, a collar fixed Within said second barrel portion in locating engagement with the outer end of said second reservoir element, said collar having a central aperture sized to receive said tip, said tip being longer than and extending through said central aperture for releasable feeding contact with said capillary spaces in said second reservoir element when said barrel portions are sealably secured together in a point covering relationship,

each of said reservoir elements defining a non-capillary air vent extending substantially its entire length and communicating with said capillary spaces therein and with said air passage, said capillary spaces in said point and said non-capillary vents and air channel permitting the movement of ink and air therethrough in opposite directions between said reservoirs to fully charge said point and to return said reservoir elements to substantially equal air-ink percentage levels while said barrel portions are in said point covering relationship after use of the imple ment, and a closure mounted on and sealing the outer end of said first barrel portion, said closure having substantially the same diameter as said reduced point section and sealably engaging said open end of said second barrel portion to isolate said second reservoir element from the atmosphere when said marking implement is conditioned for use.

References Cited UNITED STATES PATENTS 1,633,433 6/1927 Boyer et a1. 42.16 X 2,547,803 4/1951 Adams 120-4205 2,620,499 12/1952 Dressel l5--518 3,195,169 7/1965 Chadbourn 15517 ROBERT W. MICHELL, Primary Examiner.

Claims

1. A MARKING IMPLEMENT INCLUDING AN ELONGATE SUBSTANTIALLY AIR-TIGHT BARREL, A CAPILLARY RESERVOIR ELEMENT IN EACH END OF SAID BARREL, A CAPILLARY POINT EXTENDING FROM ONE OF SAID RESERVOIR ELEMENTS INTO RELEASABLE CONTACT WITH THE OTHER, SAID POINT PROVIDING A FLUID PATH EXTENDING BETWEEN AND COMMUNICATING WITH SAID RESERVOIR ELEMENTS TO PERMIT THE TRANSFER OF FLUID THEREBETWEEN AND MEANS FOR TRANSFERRING AIR BETWEEN SAID RESERVOIR ELEMENTS, SAID BARREL BEING SEPARABLE SUBSTANTIALLY INTER-