US2506035A - Writing instrument - Google Patents

Description

May 2, 1950 K. s. PARKER WRITING INSTRUMENT Filed March 22, 1945 IN VEN TOR.

Patented May 2, 1950 UNITED STATES PATENT OFFICE WRITING INSTRUMENT Kenneth S. Parker, Janesville, Wis., assigner to The Parker Pen Company, Janesville, Wis., a corporation of Wisconsin Application March 22, 1945, Serial No. 584,054

Claims.

The invention relates generally to writing instruments utilizing ink and more particularly to. a writing instrument of the ball-point type.

The general object of the invention is to provide a novel ball-point writing instrument having an ink container of a resilient self-collapsible construction and adapted to feed ink therefrom to the ball point under a slight pressure by virtue of the resilient collapsing effort exerted by the container on the ink contained therein.

Another object is to provide a novel ball-point Writing instrument having an ink containing sac of resilient material formed so that it tends to assume a collapsed state, the sac being adapted to be distended by the ink therein and by its resilience to force the ink from the sac to the ball point.

A further object is to provide a rell for a writing instrument of the foregoing character, the refill being adapted to be inserted into the barrel of the writing instrument and comprising a self-collapsing ink sac enclosed within the barrel and in communication with the ball point to feed ink thereto.

Still another object is to provide a refill for a Writing instrument of the foregoing character, which is in the form of a cartridge comprising a self-collapsing sac for the ink, enclosed Within a casing, the cartridge being readily insertible in the barrel of the writing instrument and secured i1'.-

therein in a manner to effect the feeding of ink. to the ball point by the collapsing of the sac.

A still further object is to provide an inlr cartridge comprising a sac made of resilient material and provided at one end with a discharge orifice which tends to remain closed by the resilient character of the material to retain the ink therein.

Another object is to provide an ink cartridge comprising a rigid casing enclosing a sac made of resilient material and provided with an orifice, and a removable cap for the casing providing a closure for the orice of the sac to prevent ink from being discharged therefrom during handling.

Other objects and advantages will become apl parent from the following description, taken in connection with the accompanying drawings, in which:

Figure l is a longitudinal sectional view of one form of ball-point Writing instrument embodying, the features of the invention.

Fig. 2 is a longitudinal sectional view, on an enlarged scale, of an ink cartridge adapted to be used in the Writing instrument shown in Fig. 1 and showing the cartridge empty.

Fig. 3 is a transverse sectional View taken on the line 3-3 of Fig. 2.

Fig. 4 is a view similar to Fig. 2, but showing the cartridge filled with ink.

Fig. 5 is a view similar to Fig. 4 except illustrating a closure cap applied to the front end of the cartridge.

Fig. 6 is a transverse sectional view taken on the line 6 6 of Fig. 4.

Fig. 7 is an enlarged longitudinal sectional View of the front end of the writing instrument shown in Fig. 1.

In an instrument of the type shown, the writing element, adapted to contact the writing surface, is a small ball IU which is caused to rotate by such contact and Which carries a film of ink on its surface adapted to adhere to the writing surface as the ball I0 rolls thereon. The ball is mounted in a socket in the tip portion II of the writing instrument and ink is supplied to the portion of the ball lying within the socket by means of a suitable ink feed passage I2. The ink feed passage I 2 communicates with a reservoir located within a barrel or casing I3 which is secured to the tip I I as by being threaded on a reduced shank I8 of the tip. Writing instruments of this character are adapted to utilize an ink which is relatively thick and viscous.

The ball I0 is so mounted in its socket in the tip I I that no leakage around the ball occurs, and ink may be withdrawn from the instrument solely in the form of a lm on the surface of the ball carried out of the tip by the rotation of the ball. In the present instance, the invention is not limited to any particular form of socket for the ball nor for any particular form of feed passage.

To eiect a uniform supply of ink to the ball, the ink may be fed thereto under slight pressure. To this end the reservoir is in the form of a sac I4 of circular form in communication with the feed passage I2. The sac is made of a resilient material such as rubber or the like, and is formed so as to be self-collapsing. Thus, the resilience of the material when ink is in the sac places the ink within the sac under a slight pressure, and the supply of ink therein, which tends to hold the sac in its distended form, is forced through the passage I2 to the ball III.

In its preferred form, the sac I4 constitutes the ink containing element of an ink cartridge or refill. The cartridge preferably` comprises, in addition to the sac I4, a rigid casing I5 of generally tubular form surrounding the sac I4 `to lthickened Vportion I6.

protect it in handling. In order to retain the sac I4 within the tubular casing I5, the iront or open end of the sac is enlarged as at I6 to iit snugly within and cling to the inner surface of the casing I5 and, if desired, the enlarged portion I6 may be cemented or otherwise secured to the casing. Rearwardly of the enlarged front end I6, the sac is adapted to be distended to substantially i'lll the interior of the casing when the sac is filled with ink, as shown in Figs. e and 5. In order that air within the casing externally of the sac may be discharged to prevent building up excessive pressure Within the casing during filling, the latter is provided with a vent opening I'I at its rear end. Thus, zthe interior of the casing is maintained at atmospheric pressure.

If desired, the casing I5 may be 'orrnedwithout any vent opening. In such construction, the distention of the sac I4 when ink is inserted therein, in iilling, compresses the air which is in the (casing l'5surroundingthe sac I4. The air thus compressed in the casing I5 aids'in maintaining a #pressure on'the'ink in the-sac I 4 and in collapsing the sac IA. behind the ink-asink vis withdrawnlin writing, to thereby maintain a continuous column of ink from the sac I4-to the ball ill.

-I'fY desired, -the -front -end of the sac may be lfrictionallyfttedinto the front end of the casing I5 so that air may escape past theien'larged and When so distended, ink Within the sac is under a slightpressure dueto the -resilience of the material of VWhich the sac is Iformed, and lsuch resilience 'tends -to lforce ink from the sac through an orifice 25 in thefenlarged portion fI'S whenthe cartridge is connected-with the passage I2. In korder to `cause the rear or closed end oflthe sac'to be emptied first, thesac may'have a thicknessgraduallyincreasingtoward :its rear end, as is apparent inFig. 2, so that the rearfend willtend to contract rst and thus Vforce the ink 'forwardly in the sac toward the 'orifice 253. 'During discharge of inkjthe vent I'I permits free flow'o'f air'into the casing I5 so that there willbefno tendency to form-a vacuumvtherein and thus reduce -theeffectiveness of the resiliency or" thelsae'the barrel I3, of course,`having a similar -vent|9.

The enlarged front-end I5 of -the sac is so formed th'at it'ten'ds lto fiirmly close the oriiice and thus prevent inkleaking from the sac during handling of the cartridge. However, to insure against -any such leakage, the casing Iii may be preifidod with a cap 2l tting over the end of the casing I5-and provided with a central 1stem '22lada'pted to eXtendinto-the orice'Zand maintain lit slightly distended. Thus, the resiliencel of the enlarged front end I6 causes the material thereof 5to hug tightly about 'the stem 22 and lprevent anyleakage of ink from the cartridge during handling of it fromthe time of manufactureito the time of use.

"-When the user desires to insert a cartridge of thischaracterinhis writinginstrument, he separatesthe barrel I3 from vthe tip I I. The old cartridge within Athe barrel may'then be removed vand a new one inserted, the cap 2I having been removed from the new cartridge before such insertion. During "the period after this cap vis removed and before the cartridge is secured in place in the writing instrument, no leakage through the orifice can occur since'the resilience of theenlar'ged "portion I6 causes the orifice to be closed. Afterthe cartridge has been inserted in'thebarrel I.3,'thewriting tip I'I is screwed into the barrel `and a tubular extension -`23 `on the writing tip II is forced into the orice to place the feed passage I2 in direct communication with the interior of the sac. Thus, ink will be fed from the sac by the tendency thereof to collapse, so that the ink is supplied to the ball I0 through the feed passage I2 under a slight pressure.

This application is a continuation-in-part of my 'applicationlSerial No. 527,570, led March 22, 1944, for Ink cartridge, now abandoned.

YI claim:

1. An ink package comprising a self-collapsing resilient ink containing sac having a discharge orice, the walls of said sac increasing in thickness as the distance from said orifice increases for collapsing said walls progressively in a direction toward said oriiice.

2. --An ink package comprising a self-collapsing resilient ink containing sac provided with an orifice defining portion which is self-closing due to the contractile action of the resilient material surrounding tliefori'lce.

3. An ink cartridge comprising'a rigid tubular casing vopen at one end, and a self-contracting ink containing sac positioned in said casing and having ascii-closing orifice at said open endof said casing.

'4. V-`,In a writing instrument having a ball Atype writing element, a rigid casing, a iiexible, re-

silient and self-collapsible ink vcontaining sac within said casing and yhaving a dischargeorifice linone end'thereoL-and means'including an ink -feed member having an ink Iflow duct therein connectingsaid discharge oriiice'ofsaid'sac with lsaidivriting element, the 'resilience oisaid sac constantly exerting a collapsing action-on the sac creating a pressure-tending to discharge ink through said orice and connecting means-tothe writing element, said sac being self-pressuringV `substantially throughout pr'essuring, resilient and -flexible wall member hai-.fing a Viirst surface in contact with the link and a vent passage-in saidl casingfor maintaining atmospheric pressure againsta second surface of said wall member.

6. An ink package comprising'a rigid casing for containing a supply of relatively thick, viscous ink, and aself-'pressuring resilient,'ilexible wall member insaid casing in contact withand conforming to the ink and distorted thereby, the resiliency'of said wallmember serving .tofcause it to constantly exert a'pressurezon said inkiwhich tends todischarge it from said package.

7. In a ball-pointed penemploying viscous inks comprising a Writingrball, a socketfor said ball, and an ink reservoir connected thereto, said reservoir comprising a sac composed of resilient, iiexible material, the wall of said sac being normally collapsed but expanded when ink is forced into said sac, the resiliency of said Wall, `when the Wallis thus expanded, automaticallycausing said wall to exert a pressure on said ink throughout substantially .the entire ,collapsing action of the wall tending toiforce said inktoward said Writing ball.

V.An inkcartridge adapted .to Yserve as` areseryvoir for containing viscous ink "for a pen having a writing point, and ink feed means leading thereto for connecting the writing point with the ink reservoir, said cartridge comprising a rigid elongate easing, means maintaining the ink constantly under at least atmospheric pressure including a iiexible sac member mounted in said easing and having an open end adapted for operative connection With the ink feed means, said sac member having an imperforate selfcollapsing wall which shuts oi the ink therein from the atmosphere and which is constantly engaged with the ink by its self-collapsing action to avoid the formation of a sub-atmospheric pressure Within the sac member behind the ink therein and constantly insure a continuous column of ink from the rear or closed end of said sac membei' to the ink feed means.

9. In a writing instrument, a rigid casing, a Writing element, means for supporting said writing element and providing an ink feed passage leading to said Writing element, and means including an imperforate flexible and resilient wall member in said casing for sealing a. body of ink against contact with air, said wall member being distorted by the ink and by reason of its resilience and flexibility conforming to said body of ink and constantly exerting a pressure in excess of atmospheric pressure on said body of ink to constantiy maintain a continuous column of ink from said casing to said writing element.

10. In a ball point writing instrument, arigid casing and a resilient, self-pressuring and selfcollapsible sac within said casing for holding a supply of viscous ink with the sac distended by the ink, the collapsing resilience of said sac being such as to cause said sac to apply at least atmospheric pressure on the ink substantially throughout its entire collapsing action and tending to discharge ink therefrom to the bali point, said casing being vented to maintain the space within the casing and outside of the sac at atmospheric pressure.

KENNETH S. PARKER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS OTHER REFERENCES Ser. No. 470,091, Leeuwin (A.P.C.), published July 13, '1943.

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