This invention relates to writing instruments, and more particularly to writing instruments that dispense volatile inks, such as felt tip markers and the like.
This invention relates to ink impregnated marking and writing instruments, commonly known as “markers.” The term “markers” as used herein generally includes all such writing instruments where ink may have a tendency to evaporate from its tip. Some examples of markers include, but not limited to, felt-tipped pens, dry erase, permanent and non-permanent markers, and children's markers. Markers have at least one end with a writing tip for writing onto a surface. The writing tip is also referred to as a nib. The ink formulations typically comprise dye and solvent in which the dye is dissolved. These ink solvents are typically volatile, being prone to evaporation when exposed to ambient air. If a sufficient amount of the ink solvent evaporates from the writing tip of the marker, the writing tip dries out, and the performance of the marker substantially degrades.
The problem with ink evaporating from the tip is solved by placing a cap over the tip when the marker is not in use. One of the problems with the cap is that the cap is often not put back on the tip after its use because users sometimes forget to put the cap back on or it is misplaced, and without the cap, the tip dries out to shorten the life of the marker.
To overcome the problem of having a cap for the marker, some markers are designed with a self-sealing cap integrated into the maker housing. These markers have their own problems in that the self-sealing cap designs are complex and do not work very well. One of the problems is that the writing tip is typically isolated in a relatively large air chamber when the writing instrument is not in use. With a large air chamber, a large amount of ink can still evaporate into the air chamber. Another problem is that as the tip moves in and out of the self-sealing cap there is friction between the self-sealing cap and the tip that can cause the self-sealing cap to deteriorate over time. In addition, the assembly of self-sealing caps is complex so that they may be unsuitable for high volume manufacturing processes. Therefore, there is a need for an improved self-sealing writing instrument.
This invention provides a retractable writing instrument that substantially prevents writing fluid from evaporating through the tip when the tip is in a retracted position. The retractable writing instrument includes a front barrel with a front opening to allow the tip to move in and out of the opening. Adjacent to the front opening and within the front barrel is an enclosure member that substantially seals the tip from outside air when the tip is in a retracted position. The writing instrument also includes a back barrel with a back opening. Disposed within the back opening is a plunger that is adapted to move back and forth axially. When the plunger is activated by clicking on it, for example, the tip may be moved in and out of the enclosure member and front opening. Writing fluid is stored in a feeder. A nib is between the feeder and the tip to convey the writing fluid in the feeder to the tip. The nib may be unitary with the tip or may be a separate component. At least a portion of the feeder may extend into the back opening and into the plunger to lengthen the size of the feeder to store more writing fluid.
The enclosure member includes a first end and a second end, where the first end is adapted to open to allow the tip to extend through the first end. To open, the first end may have a lip with a slit. To further assist in substantially sealing the lip in the retracted position, a clip may be provided to add compression force to the lip. The second end may have an inner configuration adapted to substantially seal the second end of the enclosure member yet allow the tip to move axially in and out when activated by the plunger. In the retracted position, the tip is between the first and second ends to substantially seal the tip from the ambient air, thereby eliminating the need for a cap.
The enclosure member may be made of a material that is durable so that the lip does not wear out after many cycles of moving the tip in and out of the enclosure member. The material should be also impermeable vapor to seal the tip from the ambient air. In this regard, the enclosure member may be made of thermoplastic vulcanizate (TPV) material including butyl rubber cross-linked with polypropylene.
Other systems, methods, features, and advantages of the invention will be or will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims.
The invention can be better understood with reference to the following figures. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like reference numerals designate corresponding parts throughout the different views.
The writing instrument 100 may include a clip 301 to aid in closing the first end 302 of the enclosure member 300. The clip 300 may be preloaded to apply compressive force on the first end 302. The enclosure member 300 may be configured so that the clip 301 may couple to the enclosure member 300 on its outer surface. In this way, the clip 301 may be disposed between the enclosing member 300 and the first barrel 104 and encircle the circumference of the second end 304 of the enclosing member 300. In addition, the second end 304 of the enclosure member 300 may have cutouts for the clip 301 so that the outer circumference of the enclosure member and the clip may combine to form the surface that contacts the inner wall of the housing 101.
The writing instrument 100 may also include a first cartridge 312 adapted to couple to a second cartridge 314. The first and second cartridges 312 and 314 are adapted to enclose a feeder 316. The feeder 316 is adapted to store writing fluid that conveys through the nib 308 and then to the tip 102. The capillary relationship among the feeder 316, nib 308, and tip 102 causes the writing fluid to convey from the feeder 316 to the tip 102. The first cartridge 312 may have an elongated portion 318 with an opening 320 adapted to receive and seal the nib 308 or tip 102. This allows the back tip 322 of the nib 308 to make contact with the feeder 316 to convey the writing fluid to the tip 102. The first cartridge 312 has a back flange 327 adapted to associate with a second cartridge member 314. The back flange 327 may have at least one tab 324 that is adapted to associate with a corresponding channel formed in the second barrel 108 so that the first cartridge 312 moves between the retracted and protracted positions without rotating. This may be done to ensure that the first cartridge moves along the axial direction 310 consistently. The elongate portion 318 of the first cartridge 312 may be inserted into the resisting member 326 such that the resisting member 326 is positioned between the second end 304 of the enclosing member 300 and the edge 325 of the first cartridge 312.
The writing instrument 100 may include a gear 328 that works with the plunger 112 and the second barrel 108 to lock the plunger 112 in the retracted position or the protracted position. The gear 328 is hollow to allow the back end of the second cartridge 314 to pass through the gear 328. The plunger 112 has a bore 114 that is adapted to receive at least a portion of the feeder 316 held within the second cartridge 314. Incorporating the feeder 316 inside the plunger 112 extends the length of the feeder 316 to store more writing fluid.
In the protracted position, the elongated portion 318 of the first cartridge 312 may extend from the first opening 106 along with the tip 102. The elongated portion 318 may assist in guiding the tip through the first end 302 of the enclosure member 300 and the first opening 106. The elongated portion 318 may have a vent 307 for allowing air into the feeder 316 when the writing instrument 100 is in use. The vent 307 may be a passage formed in the wall of the elongated portion 318, or formed between the inner wall of the elongated portion 318 and the nib 308. With the later formation of the vent 307, the size and configuration of the vent 307 may be varied by altering the outer wall configuration of the nib 308. The vent or passage may be also formed within the feeder with a certain pore size to allow air to pass to the feeder.
The elongated portion 318 may be configured so that it resides within the resisting member 326. As illustrated in
The second end 304 may have an outer configuration 700 in the form of a ring. The outer configuration may have an outer diameter sized to fit within the inner wall of the housing 101, or in the first barrel portion 104. The size of the diameter may vary so that the second end may seal around the inner wall of the housing 101, or a gap may be formed between the second end and the housing. The second end 304 may have an inner configuration 702 sized to allow the elongated portion 318 to slide forward and backwards along the longitudinal direction. The inner configuration 702 may be also sized so that it forms a substantially airtight seal around the elongated portion 318 as it slides along the longitudinal direction. This allows the vapor chamber 306 to be formed within the enclosure member 300 that is substantially sealed from the ambient air when the lip 600 is closed. In addition, the vent 307 may be formed near the tip 102 so that the enclosure member 300 may substantially seal the vent and the tip when the writing instrument 110 is in a retracted position.
The enclosure member 300 may be configured to minimize the size of the vapor chamber 306. This may be accomplished by tapering the thickness of the second wall 704 from the outer configuration 700 towards the inner configuration 702. The tapering second wall 704 may conform to provide the inner configuration that serves to guide and seal around the elongated portion 318 to minimize the space in the vapor chamber 306.
The inner configuration 702 may be configured to minimize the resistance on the elongated portion 318 as it slides back and forth. The inner configuration may have one or more edges 706 and 708 separated by a depression, reducing the thickness of the second wall 704 with every depression. Reducing the wall thickness with the edges 706 and 708 reduces the friction between the inner configuration 702 and the elongated portion 318.
The enclosure member 300 may be made of one piece as described above, or from a number of pieces. For example, the outer configuration 700 of the second end 304 may be coupled to the inner wall of the housing, and the first end 302 with the lip 600 may be coupled to the housing closer to the first opening 106, where the space between the first and second ends form the vapor chamber.
The enclosure member 300 may be made of a material that is durable and flexible so that the slit 602 does not wear out after many cycles of the tip 102 moving in and out of the slit 602. The material may have low permeability to vapor and air to seal the tip 102 from the outside air. The material may be also soft enough to provide a better seal around the imperfections in the slit and the inner configuration. In this regard, the material may have a shore hardness of about 30 to about 80, and in particular in the range of about 50 to 65. The enclosure member may be formed from a variety of materials such as silicon, butyl-rubber, and thermoplastic elastomer with thermoplastic rubber that has low-permeability to vapor. A variety of methods may be used to form the enclosure member using silicone such as injection molding, blow molding, extrusion molding, and other methods known to one skilled in the art. For alcohol-based writing fluid with higher evaporation rate, butyl rubber may be compression molded or other methods known to one skilled in the art may be used to form the enclosure member. Alternatively, the enclosure member may be formed from thermoplastic elastomer with thermoplastic rubber that has low-permeability to vapor. Such a material is manufactured by Advance Elastomer Systems, L. P. 388 South Main Street, Akron, Ohio 44311, under the name of Trefsin® that can be formed into the enclosure member 300 using a variety of methods, such as injection molding, blow molding, and extrusion molding.
Although the invention has been described with specific reference to certain exemplary embodiments, other advantages, and modifications and variations of the invention, including adaptation or incorporation of the inventive seal into writing instruments of different sizes and configurations, are all within the scope of the invention as defined by the claims and equivalents thereof.
This application claims the benefit of three Provisional Patent Applications: (1) Ser. No. 60/373,497, filed Apr. 17, 2002; (2) Ser. No. 60/386,173, filed Jun. 4, 2002; and (3) Ser. No. 60/426,917, filed Nov. 15, 2002, all entitled “Self-Sealing Retractable Writing Instrument,” which are all incorporated by reference.
Number | Name | Date | Kind |
---|---|---|---|
261457 | Hoffman | Jul 1882 | A |
1166896 | Garvey | Jan 1916 | A |
1541826 | Kroutl | Jun 1925 | A |
1809416 | Liddell | Jun 1931 | A |
2582451 | Mureau | Jan 1952 | A |
2874679 | Zepelovitch | Feb 1959 | A |
2957452 | Brannon | Oct 1960 | A |
3035299 | Gordon et al. | May 1962 | A |
3039436 | Exner | Jun 1962 | A |
3191329 | Shea | Jun 1965 | A |
3479122 | Funahashi | Nov 1969 | A |
3480370 | Koeln | Nov 1969 | A |
3525573 | Fend | Aug 1970 | A |
3583820 | Koeln | Jun 1971 | A |
3594091 | Bleuer | Jul 1971 | A |
3709619 | Zepell | Jan 1972 | A |
3652172 | Zepell | Mar 1972 | A |
3652173 | Miller et al. | Mar 1972 | A |
3905709 | Bok | Sep 1975 | A |
3922100 | Saito | Nov 1975 | A |
3941490 | Anton | Mar 1976 | A |
3945734 | Woodbridge | Mar 1976 | A |
3993409 | Hart | Nov 1976 | A |
4218154 | Erfer | Aug 1980 | A |
4269525 | Melikian | May 1981 | A |
4469462 | Hashimoto et al. | Sep 1984 | A |
4470715 | Reuchlin | Sep 1984 | A |
4479732 | Shimizu | Oct 1984 | A |
4496258 | Tanaka et al. | Jan 1985 | A |
4509541 | Manciocchi, Jr. | Apr 1985 | A |
4540300 | Midorikawa | Sep 1985 | A |
4544297 | Grossiord | Oct 1985 | A |
4556336 | San et al. | Dec 1985 | A |
4560298 | Oki et al. | Dec 1985 | A |
4572688 | Klose | Feb 1986 | A |
4588319 | Neimeyer | May 1986 | A |
4618280 | Kageyama | Oct 1986 | A |
4624594 | Sasaki et al. | Nov 1986 | A |
4629348 | Hashimoto et al. | Dec 1986 | A |
4640637 | Winthrop | Feb 1987 | A |
4696594 | Powers | Sep 1987 | A |
4711592 | Gregory | Dec 1987 | A |
4712937 | Schmidt et al. | Dec 1987 | A |
4741437 | Gorski et al. | May 1988 | A |
4759650 | Granoff | Jul 1988 | A |
4768529 | Mahruki | Sep 1988 | A |
4854759 | Morane et al. | Aug 1989 | A |
4902152 | Seidler | Feb 1990 | A |
4911570 | Rhoades | Mar 1990 | A |
4923317 | Bishop et al. | May 1990 | A |
4929107 | Kageyama et al. | May 1990 | A |
4969764 | Gregory | Nov 1990 | A |
4969766 | Nagle et al. | Nov 1990 | A |
5004362 | Palmer | Apr 1991 | A |
5017034 | Stary et al. | May 1991 | A |
5022773 | Waldinger et al. | Jun 1991 | A |
5048990 | Hashimoto et al. | Sep 1991 | A |
5067837 | Panopoulos | Nov 1991 | A |
5087144 | Wada et al. | Feb 1992 | A |
5092701 | Lai | Mar 1992 | A |
5095580 | Capponi | Mar 1992 | A |
5102251 | Kaufmann | Apr 1992 | A |
5131774 | Katz | Jul 1992 | A |
5149219 | Kageyama et al. | Sep 1992 | A |
5163767 | Lucas | Nov 1992 | A |
5171097 | Nagaoka et al. | Dec 1992 | A |
5174814 | Burwell et al. | Dec 1992 | A |
5192154 | Moeck | Mar 1993 | A |
5207523 | Wittek | May 1993 | A |
5213236 | Brown et al. | May 1993 | A |
5339995 | Brown et al. | Aug 1994 | A |
5362168 | Abe et al. | Nov 1994 | A |
5377877 | Brown et al. | Jan 1995 | A |
5397195 | Goncalves | Mar 1995 | A |
5407448 | Brandt et al. | Apr 1995 | A |
5445466 | Mukunoki | Aug 1995 | A |
5480250 | Birden | Jan 1996 | A |
5482191 | Kaufmann | Jan 1996 | A |
5641078 | Kaufmann | Jun 1997 | A |
5735623 | Gueret | Apr 1998 | A |
5823697 | Talbot | Oct 1998 | A |
5895162 | Gueret | Apr 1999 | A |
5915867 | Hashimoto | Jun 1999 | A |
5951185 | Kingsford et al. | Sep 1999 | A |
6010266 | Schrepf | Jan 2000 | A |
6033141 | Blaustein et al. | Mar 2000 | A |
6050445 | Manganiello | Apr 2000 | A |
6095706 | Hashimoto | Aug 2000 | A |
6135660 | Stevens et al. | Oct 2000 | A |
6158913 | Dumler | Dec 2000 | A |
RE37016 | Morano | Jan 2001 | E |
6174099 | Patel et al. | Jan 2001 | B1 |
6213661 | Coon | Apr 2001 | B1 |
6231256 | Kingsford | May 2001 | B1 |
6231257 | Stevens | May 2001 | B1 |
6321620 | Fabbro | Nov 2001 | B1 |
6321931 | Hakim et al. | Nov 2001 | B1 |
6371129 | Le Bras-Brown | Apr 2002 | B1 |
6402409 | Park | Jun 2002 | B1 |
6478495 | Ami et al. | Nov 2002 | B1 |
6530709 | Washington | Mar 2003 | B1 |
6588958 | Seidler | Jul 2003 | B1 |
6718990 | Chastain et al. | Apr 2004 | B1 |
20020039511 | Park | Apr 2002 | A1 |
20020131807 | Ami et al. | Sep 2002 | A1 |
Number | Date | Country |
---|---|---|
612885 | Aug 1976 | CH |
1269010 | Sep 1969 | DE |
1461588 | Dec 1969 | DE |
1561812 | Apr 1970 | DE |
1561813 | Apr 1970 | DE |
1561814 | Apr 1970 | DE |
1561830 | Apr 1970 | DE |
2124298 | May 1971 | DE |
2424918 | Dec 1975 | DE |
2752304 | Jul 1978 | DE |
2808910 | Jun 1979 | DE |
2844886 | Aug 1979 | DE |
3342141 | May 1984 | DE |
3434378 | Sep 1984 | DE |
3433393 | Mar 1986 | DE |
3434188 | Mar 1986 | DE |
3502592 | Jul 1986 | DE |
3504462 | Aug 1986 | DE |
19930540 | Jun 1989 | DE |
3916343 | Oct 1990 | DE |
4025090 | Feb 1991 | DE |
4305082 | Feb 1993 | DE |
4403771 | Feb 1994 | DE |
19610644 | Sep 1997 | DE |
29823054 | Jul 1999 | DE |
19943360 | Mar 2000 | DE |
29910459 | Nov 2000 | DE |
0063658 | Nov 1982 | EP |
0210300 | Dec 1985 | EP |
0267557 | May 1988 | EP |
0461292 | Jun 1990 | EP |
0452281 | Oct 1991 | EP |
0678075 | Apr 1997 | EP |
1424491 | Dec 1965 | FR |
1280596 | Nov 1989 | JP |
1281999 | Nov 1989 | JP |
2283499 | Nov 1990 | JP |
04316899 | Nov 1992 | JP |
08108677 | Apr 1996 | JP |
08216586 | Aug 1996 | JP |
8300872 | Nov 1996 | JP |
8318693 | Dec 1996 | JP |
08318693 | Dec 1996 | JP |
08337089 | Dec 1996 | JP |
09131994 | May 1997 | JP |
10100579 | Apr 1998 | JP |
10114187 | May 1998 | JP |
10114188A32 | May 1998 | JP |
2002187395 | Jul 2000 | JP |
2001063271 | Mar 2001 | JP |
2002178681 | Jun 2002 | JP |
WO8502149 | May 1985 | WO |
WO-9000118 | Jan 1990 | WO |
WO-0017575 | Mar 2000 | WO |
WO03068530 | Aug 2003 | WO |
Number | Date | Country | |
---|---|---|---|
20040042838 A1 | Mar 2004 | US |
Number | Date | Country | |
---|---|---|---|
60426917 | Nov 2002 | US | |
60386173 | Jun 2002 | US | |
60373497 | Apr 2002 | US |