US2914028A

US2914028A - Writing implement

Info

Publication number: US2914028A
Application number: US408317A
Authority: US
Inventors: Lynn P Martin
Original assignee: WA Sheaffer Pen Co
Current assignee: WA Sheaffer Pen Co
Priority date: 1954-02-05
Filing date: 1954-02-05
Publication date: 1959-11-24
Anticipated expiration: 1976-11-24

Description

Nov. 24, 1959 L. P. MARTIN WRITING `IrvlPLrsn/mzm v 2 Sheets-Sheet 1 Filed Feb. 5. 1954 Q QQ NRS @Nw am QW L. P. MARTIN WRITING IMPLEMENT l Nov. v24, 1959 Filed Feb. 5, 1954 2 Sheets-Sheet 2 Il fffffffffffffff n I I l l l l l A l n l l 4 l n l I I I l n l l d l if rafa! ,ffl/1711. .//7

l l n l l n A A A A A l A l n v 1 l l l l A l 4 l a x f 1 .A

IN VEN TOR.

United NStates Patent O 'i 2,914,028 WRITING IMPLEMENT Lynn P. Martin, Fort Madison, Iowa, assigner to W. A.

Sheaffer Pen Company, Fort Madison, Iowa, a corpo- This invention `relates to writing implements and has for an object the provision of a writing implement having a` valved writing fluid reservoir normally sealed against access to the atmosphere when the implement `is conditioned for writing. v v v At the present time there is no fountain pen on the market which is entirely leakproof when subject to extreme changes in temperature or barometric pressure. For example, if the ordinary fountain pen is taken in an airplane from sea level to an altitude of about 10,000 feet it will have` a tendency to leak becausethe atmospheric pressure Vat high altitudes is considerably less than the pressure within the fluid reservoir which was initially filled at lower altitudes. In some writing implements the c ap covering the writing point is vented. vIn such cases writing fluid will be expelled upon a rapid decrease in barometric pressure if the implement is held levelor with the point extending downwardly due to the expansion of theV body of air contained within the reservoir. One means that has been-used in thev past to controlthisV undesirable ,feature` toi some extentis the provision in.

the forward end ofthe writing implement ofV an expansion chamber which may take the form ofa, seriesof comb cuts and grooves.` However, such expansion chambers often are noty capable of accommodating the amount of writing fluid that may bel expelled during extreme` and'` rapid changes inthe harometric pressure- It. has also been proposed in the past to provide a cap for-the writing point of the implement whichis, substantially airtight so that; the air pressure-adjacent the writing point will not.

proof and will not expel writing fluid if the implement is subjected to rapid/changes in atmospheric pressuresuch as may be encountered whenthe implement is taken ajloft in an airplane. l

A further object of this` invention is the provision of a writing implement which is proof against leakage-even though rapidly taken to` high altitudes and even though the cap is suddenly removed whenthe implement is Iheld in a fiat or point-down position.

A still further object of thisinvention is the provision of a writing implement which may be readily filled with writing fluid but which is always in Vcondition for limimmediate andclean writing even though subjected to extreme and rapid changes in ambient temperatures and pressures.

A still' further object of this invention `is the provision ofawritingimplement having a primary fluidy reservoirV which is normally sealed fromthe 'atmosphere when it is` in condition for writing;

A still further object of'this invention is thegprovision 2,914,028 Patented Nov. 24, 1959 ice of a writing implement having a normally sealed primary reservoir and a normally vented secondary reservoir from which fluid is withdrawn during the writing operation but whichmay be readily replenished from the primary fluid reservoir by simple manipulation.

A still further object of this invention is the provision of a Writing implement having the characteristics indicated above but which may be quickly and easily filled through the forward end of a filling tube reciprocable to a position forwardly of the writing point.

Further and additional objects will appear from the following description, the accompanying drawings and the appended claims.

In accordance with one embodiment of this invention, a writing implement is provided which comprises a barrel, a writing point and a primary fluid reservoir for holding the principal supply of'writing fluid eventually to be supplied tothe point during the writing operation. In addition the implement is provided with a secondary fluid reselvoir preferably positioned in a forward end of the implement between the writing point. and the primaryV resi ervoir. A iirst fluid passageway is provided between the primary and secondary reservoirs and a second fluid passageway is provided between the secondary reservoir and the writing point. The first passageway is provided with a firstvalve and the second passageway is provided witha second valve and there is also provided a manually operable valve control means movable to a first position whereby to open both valvesv to condition the implement forllin'g, movable to a second position whereby to close the first valve while the second valve is open whereby to* condition the implement for writing, and movable tota third. position whereby to close the second valve` while the first valve is open to' permit fluid flow between the primary and. secondary reservoirs while the reservoirs are sealed. against venting or access to the atmosphere. By this construction when the valvecontrol meanszis. shifted to the first position the implement is conditioned for filling purposes so that the primary reseryoir may be filled fromA an external, body of writing fluid. When the valve control means is moved to the secondi` position the primary reservoir is sealed and the fluid during writing is withdrawn solely from the secondaryi reservoir or any Vauxiliary expansion chambers that mayv be provided. in the forward end of the implement. When nthe valve control means is moved to the a third position the passageway between' the primary andV secondary reservoir is open'to permit the transfer of writingallui'd from the primary reservoir to the secondary reservoirbut at the same time both reservoirs are sealed against access tothe atmosphere so that the fluid transfer between the two reservoirs may be more readily effected;

This invention is` particularly useful in a writing implementahavingaifillingtube which is extendible to a position forwardlyl of the writingpoint for4 filling purposes, such an implement being disclosed in my' copending application4v Serial No. 256,897, filed November 17, 1951, now Patent- No. 2,769,427, issued November 6, 1956. The primary.` reservoir is preferably of the collapsible type and-in; a preferred. embodiment ofithis invention takes the form of a pneumatically collapsible sac of theitype'V -disclosedz in saidPatent 2,769,427 and claimed in my' priorfPatent No. 2,610,612. Thus in a preferred embodiment of-the invention, the primary uid reservoir and thel forwardly extending' filling tubezare reciprocable reservoir and, is provided vwith openings in the'rearward and forward walls thereof through which the tube passes in duid-sealing relationship. The filling tube is provided with a first longitudinal opening or passageway communicating between the primary reservoir and the secondary reservoir and with a second longitudinal opening or passageway communicating the forward open end of the filling tube with the secondary reservoir. A pair of valve means are also provided, the first of which closes off the first opening or passageway when the forward end of the filling tube is in the retracted position whereby the primary reservoir is sealed against access to the atmosphere or the secondary reservoir, and the second of which closes off the second opening when the forward end of the filling tube is in the intermediate position whereby both reservoirs are sealed against access to the atmosphere and writing fluid may be readily transferred from the primary to the secondary reservoir in the manner hereinafter to be described. In this preferred embodiment of the invention, the manually operable means for controlling the valves is associated with the plunger mechanism for collapsing the reservoir so that only single means is provided for conditioning the implement for filling, for writing lor for transferring fluid from the primary reservoir to the secondary reservoir, as will be hereinafter more fully described.

For a more complete understanding of this invention, reference will now be made to the accompanying drawings, wherein Fig. 1 is an enlarged broken sectional view of the forward end of a writing implement constructed in accordance with one embodiment of this invention showing the filling tube extended to condition the implement for filling the primary reservoir with a Writing fluid from an external source;

Fig. la is a broken sectional view of the rearward end of the implement showing the positioning of the various parts in the rear end of the implement when the filling tube is extended as shown in Fig. 1;

Fig. 2 is a sectional view taken along the line 2'- of Fig. 1a;

Fig. 3 is a broken sectional view of the implement shown in Figs. 1 and la somewhat reduced in Scale showing the filling tube and associated valves moved to an intermediate position;

Fig. 4 is similar to Fig. 3 but showing the implement conditioned for writing;

Fig. 5 is a sectional view taken along the line 5'- i of Fig. 3.but enlarged to the scale of Fig. l; and

Fig. 6 is a sectional view taken along the line 6'-6' of Fig. 4 but enlarged to the Scale of Fig. 1.

The implement shown in the drawings comprises a barrel 10, a rearward manually operable means or cap 12, a forward gripping section 14, a nib holder 16, a writing nib 18 having a writing point 20, and a feed bar 22 having comb cuts 24 and grooves 26 forming the usual type of expansion chamber for the device. Within the barrel is positioned a cartridge unit of the general type disclosed in my Patent 2,769,427 which comprises a pneumatically collapsible primary writing uid reservoir 2S, a reservoir protector tube or sheath 30' having an open rearward end 32, a forwardly extending filling tube 34 and a bushing 36 (see Fig. 4). The bushing serves as a support for the filling tube 34, the primary reservoir 28 and the protector tube 30. This cartridge unit is longitudinally reciprocable within the barrel 10 from the writing position shown in Fig. 4 to the filling position shown in Figs. 1 and 1a. The cartridge unit is restrained against axial rotation within the barrel byl means of deformations 38 in the forward end of the protector tube 30 and the bushing 36 which deformations ride in splined grooves 40 formed on the inner wall ofv the gripping section 14.

A first plunger tube 42 having an unvented rear end is secured to the cap member 12 by means of a screw 44, a rubber gasket 46 being provided to prevent lventing at the rear end of the plunger tube. A secondary-fot auxiliary plunger tube 48 extending only for a short distance forwardly of the screw 44 is also secured to the cap 12 for a purpose hereinafter to be more fully described. The plunger tube 42 is provided with a longitudinal groove 50 in the rearward end thereof which is adapted to span a packing gland 52 when the cap is moved to its retracted position thereby providing in combination with an aperture 54 in the barrel 12v a vent. for the interior of the barrel 10 when the cap is moved to the position shown in Figs. 1, 1a, 3 and 4. The forward end of the plunger tube 42 is also provided with a venting aperture 56 (see Fig. la) in a side wall thereof which in effect provides a by-pass for the packing gland 52 and therefore vents the space containing the collapsible reservoir when the cap member 12 is moved longitudinally to its most rearward position during the filling operation which position is not shown in the drawings but which will be readily understood from a consideration of the disclosure in my issued Patent No. 2,610,612 and my copending application Serial No. 256,897. The forwardl end of the plunger tube 42 is provided with threads 58 which may be engaged with corresponding threads 60 formed on the forward end of the protector tube 30. Thus when the cap 12 and the plunger tube 42 are axially rotated within the barrel 10, and while the

threads

60 and 58 are in engagement, the cartridge unit including the reservoir 28 and the filling tube 34 will separate from the cap member 12, it being remembered that the cartridge unit is held against axial rotation by the grooves 40 in the gripping section 14. A spring 62 is compressed between a shoulder 64 of barrel 10 and a collar 66 'l secured to the forward 'end of the protector tube 30.

Thus when the cap 12 is rotated, the spring 62 normally reciprocates the cartridge unit in a forward direction,'

causing the forward open end of the filling tube 34 to project forwardly of the writing point 20 whereby tov strikes the end of the gripping section 14, as shown in Fig. 1, then the forward motion of the cartridge unit stops and the cap 12 begins to separate from the barrel 10 while the

threads

58 and 60 continue to be in engagement. When these threads become disengaged, then the cap 12 and the plunger tube 42 may be manually pulled rearwardly to a position not shown in the drawings. The rearward movement of the cap and plunger tube is limited by abutment of a shoulder 68 on the plunger tube against an inner shoulder 70 on the barrel v 10 near the packing gland 52.

A secondary fluid reservoir denjng means is retained within the gripping section 14 and comprises a hollow4 readily observed. The plug 72 has a rearward wall 76 and a forward wall 78. These walls are quite thick and have axial openings and 82 therein for receiving the filling tube 34 that is reciprocated therethrough. The plug 72 also includes an auxiliary chamber 84 positioned forwardly of the opening 82 and having a diameter somewhat larger than said opening. The filling tube 34 also extends through this auxiliary chamber 84 and through an opening 86 positioned in the forward Wall thereof.

As will be understood, the filling tube 34 in combination with the secondary reservoir 74 including the auxiliary chamber 84 provides the sole means for conducting writing fiuid into the primary and secondary reservoirs of the implement and provides the sole means for supplying Writing fluid from the primary reservoir Ito the. `secondary reservoir and from the secondary reservoir to the vwriting point 20. The filling tube has a first longitudinal passage 88 communicating the primary reservoir with. the seeendary reserveilrjuhea the, various elemente, Off the implement are POSitOHeQeSfShO-Wll. i?, Het.' `l` 3.11.4' Sof lthe drawings.' The filling tube 314,'alsof'has .a second longitudinal passageway 90 communicating the forward open end of the iilling tube with vthe secondary reservoir 74 when the elements 'of the implementy are in the positions shown -in Figs. `l and 4 ofy the drawings.` A central section 92 of the filling ,pinched or lotherwise provided with an obstruction tofprevent communication between the longitudinal passageways 88 and v90 through the tube itself, it being understood that the tube is provided with two

transverse openings

94 and 96 for- 'wardly and rearwardly of the pinched section 92 so'that the tube passageways can communicate `'with each other only exteriorly of thetube. Opening 96, the portion of tube 90 disposed rearwardly ofjthe pinchedl portion 92, and the rearward portion 76 Yof resilient plug 72 form a first slide valve, and opening v94, the portion ofv tube 90 disposed forwardly'of the .pinched lportion 92 and the forward section 78 of plug 72 f onrn a second slide valve.

The filling tube 34 is formed of thinjwall sheetmetal and is provided with a plastic insertV 98 at each end having a semicircular cross section `provided with a groove 100,:as most clearly shown in Fig.` 6. The groove 100 provides an ink feeding channel 'while the remainder of the space in the tube provides an air vent channel, all. as will be clear from a consideration'of the disclosure in my Patent 2,769,427 and in` another of my copending applications Serial No. 368,852, iiled July 20, 1953, now abandoned. The forward endrof the iilling tube is provided with a slit 102 and the inserts `98 in both the forward and rearward sections of the tube are cut entirely through to provide channels 104', 106 and 108 cornmunicating the passageways with theopenings' '102, 94 and 96, respectively. t A

When the implement isin Vthe normal writing position, as shown in Fig. 4, the passageway 90 of theiilling tube 34 serves to communicateftheopen end ofl theV tube and the writing point directlyfwithfjthe secondary reservoir 74. At the same time, however', opening 96 of the rearward portion of the fillingv tubehasbeen withdrawn from the secondary reservoir 7,4 and 'thus the primary reservoir 28 is completely sealed olf; In this position the auxiliary plunger `48 secured to the rear carp member 12 engages the rear end offthe lcollapsible reservoir 28 to cause it to deform slightly'in somewhat the .same manner as shown in Fig. 4. j

1n order to lill the primary reservoir of the instrument with writing fluid, the 12 is rotated with respect to the barrel and by reason of the threaded engagement of the plunger tube 42 with the protector tube 30 the cartridge unit including the reservoir 28 and the iilling tube 34 are driven forwardly by means of spring 62. When the cartridgeunit has reached this forwardmost position by abutment of the collar`66 against the rear end of the gripping lsection 44, the several elements Iare positioned as shown in Figs. `l and la with the forward end of the filling tube moved toits forwardmost position. Thereafter the cap is vfurther rotated and thereby moved in a rearward direction with respect to the barrel for a small distance until such time as the

threads

58 and 60 havebecn disengaged; The cap `12 is then manually pulled rearwardly with respect to the barrel until such time as the shoulder 68 on the plunger tube 42 abuts the shoulder 70 on theV barrel 10. At this time `the aperture 56 is positioned rearwardly of the packing gland 52 and the interior of the barrel and the plunger tube is thereby vented totheatmosphere'through the opening 54. The open forward end of the filling tube 34 is then immersed in the writing uid and the cap 12 and the plunger tube 42 aremoved axially in a forward direction until such time as the threads 58 meet the threads 68. This downward stroke of the cap and plunger tube causes a momentary build-up of air pres- 6 eure within.. spate. letiileri by the barrel. and. the Pleuger tube, '..resultinzi ini eeglplete feellerse et the r. ifeir 2,8 t theharrel; an@ 'e plunger tule 'eemprlfee e Collapsible Chamber er. "means fer eellapsingthe Pri# mary reservoir 'ligwefve` when thethread 58 21114160 comeV intoinitialengagenient, the venting groove 50 spanning the packing gland 52'comes `into play, thus venting the compressed air within the barrel. The resilient' nature of the, collapsible sac causes it to expandwithin Ythe protector tube 30 whereby a full charge of writing iiuid is sucked into the primaryreservor from the forward open end of the filling tube. lIt 'will beund'ers-tood that the initial venting of air from andintake of writing fluid into the primary reservoir during this iilling opera-l tion is through passageway` 90, channel 106, opening 94, auxiliary chamber 84, opening 78, `secondary reservoir '74. opening 96, channel 1'08 and passageway 88.

It will be apparent that at thisfpoint 'in the operation the secondary reservoir 74l is alsofilled with writing fluid. Thereafter the cap "12 is rotated so that the threads v58 in engagement with theV threads 60 cause the capY to seat on theend of the barrellfollowed `by the withdrawal of the cartridge Aunit including the filling tube 34 in ay rearward direction against the action of the spring 62. When the llingtube and cartridge unit have reached the rearwardmost position, asfshowninFig. 4, the implement is now conditioned for writing. In this condition, however, the opening 96 on the rearward portion of the filling tube 34-is no Vlonger in communication with the secondary reservoir 74 and accordingly, the primary reservoir is completely sealed off from the atmosphere. At the same time, opening 94-extends within the secondary reservoir 74 and liuid'maygbel fed directly to the writing point 20, as will beunderstood"from` the consideration of my prior application Serial No. 368,852. At the samel time air for venting purposes will pass through the channel into the secondary reservoiras will be understood.

inasmuch as in this writing position the primary reservoir `is completely sealed, Athere is no lpossibility that any writing fluid can be expelled therefrom on account of sudden changes in temperature or barometric pressure. Thus the implement is` substantially' proof against leakage even `though it beuncapped with the point downward immediately after being taken "aloft to a considerable heightV in an airplane. The secondary reservoir 74 is comparatively: small 'so that any expansion of any air therein due to ambient pressurechanges can be readily taken care of by theY expansion chamber formed by the combcuts and grooves 24 and 26 formed in the feed vbarv 22 of theiniplement.

When the secondary reservoir 74 has become exhausted,it is then necessary 'to replenish the supply from the primary reservoir., This may b e'eiectedby manually rotating the cap 1-2 with `respect to the barrel 10 to position the elements in the relationship shown in Fig. 3. This positioning of the elements maybe indicated to the user Iby suitable indicia 1110 and 112 secured to the rear portion of the barrel andthe forward portion of the cap whereby the user is advised of the proper degree to which the `cap is to be turned to effect this positioning of the elements. It Will be understood, of course, that various types of indicia or spring detent `means could be employed to indicate this condition.

When the several parts are in this `intermediate condition (as shown in Fig. 3), the opening 94 is blocked by the forwardwall 78 so that there is no communication between the'svecondary reservoir o r the' primary reservoir and the open end of the filling tube 34. However, in this position the secondary and primary reservoirs are in communication through the` opening 9,6, the channel 108 and the passageway 88. While this limited filling tube reciprocation is occurring, the auxiliary plunger 48 on the cap 12 becomes disengaged 4from therear end of the reservoir 2,8 which then has a tendency to asia-62s assume its fully expanded condition thereby creating a slight vacuum within the reservoir 28. When 'thistoccurs .and when the filling tube openings andchannels come into the position just described, then a charge of air is sucked into the primary reservoir 28.- Thereupon if the implement is held in an upright position and with the pen point down, a charge of ink will be propelled into the secondary reservoir from the primary reservoir if the cap is screwed back to the writing position since the auxiliary plunger 48 now ypartially collapses the reservoir 28, as indicated in Fig. 4. Y Thus, by turning the cap or manually operable means to a limited extent back and forth the writing fluid will be pumped from the primary reservoir to the secondary reservoir until such time as the secondary reservoir is filled. Thereafter the cap is returned to its at rest or writing position and the implement is ready for writing in the usual manner. 'Inasmuch as the filling tube 34 is reciprocable through the openings ,80 and82 in the'forward and rearward walls of the plug 72 in fluid-sealing relationship, these walls in combination with

openings

94 and 96 form slide valves for each'of thetwo longitudinal passageways for the purposes previously set forth.

While a particular embodiment of this invention is shown above, it will be understood, of course, that the invention is not to be limited thereto, since many modifications may be made, and it is contemplated, therefore, bythe appendedfclaims, to cover any'such modifications as fall within' the true spirit and scope of this invention.

I claim: A

.1. A writing implement comprising a barrel, a writing point, a primaryfiuid reservoir within said barrel, a secondary fluid reservoir positioned between said primary reservoir and said point, `said barrel defining wall means intermediate said writing point and said secondary reservoirand intermediate said primary and secondary reservoirs, and a filling and feeding tube having an open forward end adjacent said writing point reciprocable with respect to said-point to an extended filling position forwardly thereof, a retracted writing position and an intermediate position, said filling tube having a longitudinal passageway extending therethrough, said tube having an aperture alignable with said wall means to comprise a first valve for establishing fluid communication between said primary and said secondary reservoirs only when said filling tube is reciprocated to said intermediate and said extended positions, andpsaid tube having an aperture alignable with said wall means to comprisea second valve for establishing fluid communication between said open end and said secondary reservoir only when said filling'tube is reciprocated to said retracted and extended positions, said first and second valves being so related that they are closed for all positions of said writing tube between said intermediate and said retracted positions.

2. A writing implement comprising a barrel, a writing point, a longitudinally reciprocable cartridge unit including a primary fluid reservoir `and a forwardly extending filling -tube having a longitudinal passageway and a forward open end movable to an extended position forwardly of said point, to a retracted position rearwardly of said point and to an intermediate position, a stationary secondary reservoir forwardly of said unit having forward, intermediate,- andV rearward walls provided with openings through which said tube passes in fluid sealing relationship, said filling tube having a first opening axially aligned with said secondary reservoir and providing fluid connection-between said primaryreservoir and said secondary reservoir only when in said extended and intermediate positions and having a second opening axially aligned with said secondary reservoir and providing fluid connection between said forward open end and said secondary reservoir only when in said extended and retracted positions and axially aligned with said intermediate wall when in said intermediate position, said llongitudinal passageway having anl obstruction between said openings4 dividing said passageway into two sections communicating with each other only exteriorly of said tube through said openings, and manually operable means for reciprocating said unit to said'positions within said barrel.

Y 3. The writing implement recited in claim 2 including means for partially collapsing said primary reservoir upon movement of said unit from said intermediate posi-l tion to said retracted position whereby fluid is transferred between said reservoirs upon reciprocation of said unit between said positions.

4. A writing implement comprising a barrel, a writing point, a longitudinally reciprocable cartridge unit including a primary fluid reservoir and a forwardly extending filling tube having a longitudinal passageway and a forward open end movable to an extended position forwardly of said point, to a retracted position rearwardly of said point and to an intermediate position, means for restraining said unit against axial rotation in said barrel, a stationary secondary reservoir forwardly of said unit having forward, intermediate, and rearward walls provided with openings through which said tube passes and is reciprocated in fluid-sealing relationship, said filling tube having a first opening axially aligned with said secondary reservoir and providing fiuid connection between said primary reservoir and said secondary reservoir only when in said extended and intermediate positions and having a second opening axially `aligned with said secondary reservoir and providing fluid connection between said forward open end and said secondary reservoir only when in said extended and retracted positions and axially aligned with said intermediate wall when in said intermediate position, said longitudinal passageway having an obstruction between said openings dividing said passageway into two sections communicating with each other only exteriorly of said tube through said openings, and axially rotatable manually operable means in threaded engagement with said vunit for reciprocating said unit to said positions within said barrel.

5. A writing implement comprising a barrel, a writing point, Ia longitudinally reciprocable cartridge unitl including a collapsible primary fluid reservoir and a forwardly extending filling tube having `a longitudinal passageway and a forward open end movable to an extended position forwardly of said point, to a retracted position rearwardly of said point and to an intermediate position, an axially reciprocable plunger in threaded engagement with said unit to move said filling tube to said positions, said plunger collapsing said primary reservoir for filling purposes when said unit is reciprocated to said extended position, means for restraining said unit against axial rotation within said barrel, a stationary secondary reservoir forwardly of said unit having centrally aperturedforward, intermediate, and rearward walls through which said tube passes and is reciprocated in fluid-sealing relationship, said filling tube having a first opening axially aligned with said secondary reservoir and providing fluid connection between said primary reservoir and said secondary reservoir when in said extended and intermediate positions and having a second opening axially aligned with said secondary reservoir and providing fluid connection between said forward open end and said secondary reservoir when in said extended and retracted positions and axially aligned with said intermediate wall when in said intermediate position, said longitudinal passageway having an obstruction between said openings dividing said passageway into two sections communicating with each other only exteriorly of said tube through said openings.

6. A writing implement comprising a barrel, a writing point, a longitudinally reciprocable cartridge unit including a collapsible primary fluid reservoir, a protective sheath for said primary reservoir and a forwardly extending filling tube having a longitudinal passage and a forward open end movable to an extended position forwardly of said point, to a retracted position rearwardly of said point and to an intermediate position, an axially reciprocable plunger including a sleeve member between the sheath and the barrel and a manually accessible cap on the rearward end of said barrel in threaded engagement with said unit to move said filling tube to said positions, said plunger collapsing said primary reservoir for` filling purposes when said unit is reciprocated to said extended position, means for restraining said unit against axial rotation within said barrel, a stationary secondary reservoir forwardly of said unit having centrally apertured forward, intermediate, and rearward walls through which said tube passes and is reciprocated in fluid-sealing relationship, said lling tube having a first opening axially aligned with said secondary reservoir and providing fluid connection between said primary reservoir and said secondary reservoir when in said extended and intermediate positions and having a separate` second opening axially aligned with said secondary reservoir and providing fluid connection between said forward open end and said secondary reservoir when in said extended and retracted positions and axially aligned with said intermediate wall when in said intermediate position, said longitudinal passageway having an obstruction between said openings dividing said passageway into two sections communicating with each other only exteriorly of said tube through said openings.

7. The writing implement recited in claim 6 including an auxiliary plunger secured to said cap for partially collapsing said primary reservoir upon movement of said unit from said intermediate position to said retracted position whereby fluid is transferred between said reservoirs upon reciprocation of said unit between said positions.

8. A writing implement comprising a barrel, a writing point, a primary fiuid reservoir, a secondary fiuid reservoir, a first wall member having a first opening between said primary and said secondary reservoirs, a second wall member having a second opening between said secondary reservoir and said writing point, a first valve in said first wall member for closing said first opening and sealing said primary reservoir against access to said secondary reservoir, a second valve in said second wall member for closing said second opening preventing the fiow of iiuid to said writing point from said secondary reservoir, and manually operable means connected to said first and second valves for longitudinally moving said valves together and maintaining a fixed sequential operating relationship between said valves, said valves being movable together between a first position in which both of said Valves are open for filling said implement, a second position in which said first Valve is closed and said second valve is open and in condition for writing, and a third position in which said second valve is closed and said first valve open for transferring fluid between said reservoirs while the latter are sealed against access to the atmosphere, said first and second valves being closed for all intermediate positions of said valves between said second and third positions.

References Cited in the file of this patent UNITED STATES PATENTS 2,528,327 Baker Oct. 31, 1950 2,724,366 Miessner Nov. 22, 1955 FOREIGN PATENTS 20,065 Great Britain 1907 6,570 Great Britain 1915