Patent Application
20060228163
The present invention is directed to art instruments, and more particularly to art instruments having a self-contained reservoir for dispensing paint or ink to a paintbrush portion provided on one end of the instrument.
Known art instruments include instruments having an internal reservoir portion for holding water, colored inks, paints, and other liquid art media (hereinafter collectively “ink”) and a brush portion connected to the reservoir portion for permitting the water or ink to pass through the brush portion for deposit on a desired surface to be painted. For example, U.S. Pat. No. 6,536,969 to Nishitani (assigned to Kuretake Co. Ltd) (the '969 patent) discloses an artist's instrument having a movable body and spring apparatus for controlling flow of ink out of a self-contained reservoir.
Another commercially available ink-dispensing brush is the Art-Kure Watercolour System Colour Sketch Brush (hereinafter the “Art-Kure brush”). The Art-Kure brush includes a body having an ink reservoir connected to a brush portion by an ink-dispensing assembly. The ink dispensing assembly includes a reservoir body having a closed end and an opposite open end, the open end having means for connecting the reservoir body to a nozzle and brush assembly. The ink-dispensing assembly further comprises an outer capillary tube, an inner capillary tube nested inside the outer capillary tube, an open plug inserted into one end of the outer capillary tube and acting as a travel stop for the inner capillary tube, and a secondary orifice restrictor. The secondary orifice restrictor includes a tube-receiving end having a recessed stepped portion for receiving the unencumbered end of the inner capillary tube and a stepped outer surface having a cross-sectional diameter that permits the tube-receiving end to be inserted into the unencumbered end of the outer capillary tube. The secondary orifice restrictor further includes an axial channel that protrudes along the entire axial length of the restrictor. The axial channel is generally cylindrical, and includes at least one stepped portion for receiving a solid pin having a first large-diameter end and an opposite small-diameter end. The large diameter end is inserted into the channel adjacent the tube-receiving end and is pushed up the channel until it reaches the stepped channel adjacent the opposite end of the secondary orifice restrictor, so that the large-diameter end is nearly flush with the terminal end of the channel adjacent the second end of the secondary orifice restrictor, thereby blocking flow through the secondary orifice restrictor. The small-diameter end of the pin protrudes into the channel provided in the inner capillary tube.
The Art-Kure brush's ink-dispensing assembly further includes a primary orifice restrictor having a protruding tube end, an opposite end, and a channel linking the two ends. The protruding tube end is configured so as to penetrate the axial channel of the secondary orifice restrictor and to displace the large-diameter end of the solid pin upon activation of the ink-dispensing system by a user. Displacing the pin permits ink to flow through the open plug into the outer capillary tube and then into the inner capillary tube, around the solid pin and through the axial channel of the secondary orifice restrictor, and through the axial channel of the primary orifice restrictor. The opposite end of the primary orifice restrictor is disposed in close proximity to a bristle portion, the bristle portion surrounded by a valve body having slotted sidewalls to permit the ink flowing from the primary orifice restrictor primarily around the outer perimeter bristles (versus uniformly through or between all bristles) and through the valve body and outside of the valve body, eventually reaching the tapered end of the brush portion for distribution onto a surface to be painted. The brush portion is nested inside the slotted valve body, and the slotted valve body is held in place by a nozzle threaded onto the threaded end of the reservoir body. The Art-Kure brush further includes a shipping ring that is situated between the threaded nozzle and the body, thereby preventing the full threading of the nozzle portion onto the reservoir body which would otherwise press the primary restrictor against the secondary restrictor to activate the secondary restrictor by compressing the pin to allow flow through the axial chamber of the secondary orifice restrictor. Removal of the shipping ring is accomplished by unscrewing a threaded nozzle and brush portion, removing the shipping ring, and re-tightening the threaded nozzle and brush portion onto the body. Re-tightening in this manner compresses a pin located in the secondary orifice restrictor, thereby opening a central passageway in the restrictor to allow ink to flow from the nested capillary tube system through the central passageway and the pin, and into the valve body and brush portion.
Despite some desirable features, the Art-Kure brush is prone to leaking after activation, whether in use or in storage. Leakage is especially prevalent from the brush end of the threaded nozzle portion, and is exacerbated by Art-Kure's use of thin inks having a viscosity of less than about below about 5 centipoise (cps) in conjunction with the slotted valve body, which allows ink to escape the nozzle body and to leak from any gap between the outer nozzle body and valve body, especially around the protruding bristle end of the nozzle. Additionally, thin ink that returns from outside of the valve body under user pressure travels primarily across the outer perimeter bristles of the bristle assembly, rather than evenly throughout all bristles of the bristle assembly. Moreover, once user pressure on the reservoir is released, the Art-Kure bristle portion does not self-wick to continually draw ink from the reservoir, but rather requires the user to re-apply reservoir pressure. Additionally, the Art-Kure brush allows ink to spurt from the brush under user pressure because the slotted structure of the valve body allows the low-viscosity ink to flow outside of the valve body and spurt from the gap between the outer bristles and the valve body, as well as from the gap between the valve body and the threaded nozzle. Such splattering occurs when a user firmly squeezes the reservoir body because the slotted valve body provides virtually no resistance to ink flow, and the flow is unchecked by the bristle assembly, thereby allowing substantially unimpeded flow in response to user pressure on the body. Furthermore, Art-Kure's inclusion of a very porous, open cell cylindrical sponge around the base of the slotted valve body adjacent the bristle base, in combination with ink below 5 cps, does not effectively control flow or mitigate against splatters resulting from firm squeezing of the body reservoir by a user. Additionally, it is believed that Art-Kure's nested capillary system is not optimized for smooth and consistent flow of ink, and particularly not for inks having viscosities of less than about 5 cps. Furthermore, Art-Kure's brush assembly is not suitable for inks having viscosity of greater than about 10 cps.
Thus, the complex assemblies of the '969 patent, the Art-Kure Brush, and other known artist's instruments fail to provide adequate, reliable control of ink to and through a brush portion as required for desirable, high-quality art projects. Moreover, known art instruments having self-contained fluid reservoirs lack features to render the instrument leak-proof during shipping, yet easy to activate for desirable fluid flow, self-wicking, and optimal controlled distribution onto a desired surface to be painted.
Therefore, what is required is an improved art instrument that provides smooth, even, controllable ink flow for inks of various preselected viscosities, and that is substantially leak-proof both before and after activation by a consumer.
The present invention provides an art instrument having a self-contained liquid reservoir for storing paint or ink, the reservoir communicably linked to a brush portion by an ink-dispensing assembly. The instrument comprises a reservoir body having a closed end and an opposite open end, the open end having means for connecting the reservoir body to a nozzle and brush assembly. The ink-dispensing assembly further comprises an outer capillary tube, an inner capillary tube nested inside the outer capillary tube, an open plug inserted into one end of the outer capillary tube and acting as a travel stop for the inner capillary tube, and a secondary orifice restrictor. The secondary orifice restrictor includes a tube-receiving end having a recessed stepped portion for receiving the unencumbered end of the inner capillary tube and a stepped outer surface having a cross-sectional diameter that permits the tube-receiving end to be inserted into the unencumbered end of the outer capillary tube. The secondary orifice restrictor further includes an axial channel that protrudes along the entire axial length of the restrictor. The axial channel is generally cylindrical, and includes at least one stepped portion for receiving a pin (whether hollow or solid) having a first large-diameter end and an opposite small-diameter end. The large diameter end is inserted into the channel adjacent the tube-receiving end and is pushed up the channel until it reaches the stepped channel adjacent the opposite end of the secondary orifice restrictor, so that the large-diameter end is nearly flush with the terminal end of the channel adjacent the second end of the secondary orifice restrictor. The opposite small-diameter end of the pin protrudes into, but preferably does not completely obstruct, the channel of the inner capillary tube.
The ink-dispensing assembly further includes a primary orifice restrictor having a protruding tube end, an opposite end, and a channel linking the two ends. The protruding tube end is configured so as to penetrate the axial channel of the secondary orifice restrictor and to displace the large-diameter end of the pin upon activation of the ink-dispensing system by a user. Displacing the pin permits ink to flow through the open plug into the outer capillary tube and inner capillary tube, into the axial channel of the pin, through the axial channel of the secondary orifice restrictor, and through the axial channel of the primary orifice restrictor. Because the opposite end of the primary orifice restrictor is disposed in close proximity to a bristle portion, the ink flowing from the primary orifice restrictor immediately meets the open end of the valve body adjacent the base of the bristle portion. The valve body controls and directs ink flow through and around the bristles to the tapered distal end of the brush portion for distribution onto a surface to be painted. Preferably, the brush portion and valve body are held in place by a nozzle tightly threaded onto the threaded end of the reservoir body.
Other features and advantages of the present invention will be apparent from the following more detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.
FIGS. 5A through 5Cc illustrate the bristle component of the art instrument in accordance with one embodiment of the present invention.
The present invention is directed to an art instrument in the form of a paintbrush having a self-contained paint reservoir and means for controlling the dispensing of paint from the reservoir to a brush portion for distributing paint to a desired surface to be painted.
Referring to the drawings,
As shown in
As further described herein, the paintbrush is initially activated by a user disassembling the instrument, removing the ring 9, and reassembling the instrument to activate the dispensing components. Thereafter, the instrument is activated by a user exerting pressure on the reservoir body 10, such as by gently squeezing the reservoir body 10. Because of the airtight assembly of the paintbrush, the user-exerted pressure is translated to the liquid ink or liquid paint contained in the reservoir body 10, forcing the liquid through the internal dispensing components to the bristle portion 4, as further described herein.
As illustrated in
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The primary functions of the valve body 3 are to support the bristle assembly 4, and to direct and regulate ink flow in a controlled fashion. The present invention provides two embodiments of the valve body 3, each embodiment directed to optimal control of ink flow inks of differing preselected viscosities, but can also be selected based upon the desired application, for example, applications requiring different delivery rates and volumes of ink. The embodiments include a first non-vented sidewall embodiment such as that as shown in
In the first embodiment shown in
In the second embodiment shown in
In the first embodiment of the valve body 3 shown in
In the second embodiment shown in
Another purpose of the valve body 3 is to provide a housing to position the bristle assembly against the primary orifice restrictor 6. If the bristle assembly is not positioned properly against the primary orifice restrictor then the ink flow will not be directed smoothly to the distal end 506 of the bristle portion 4. For example, experiments using the vented valve bodies of
As previously described, the vented embodiment of the valve body 3 is most compatible with inks or paints having a viscosity of greater than about 5 cps. In contrast, preferred embodiments of the non-vented valve body 3 utilize inks having a viscosity of less than about 5 cps to provide optimal smooth and controllable ink flow where the body portion 504 adjacent the capped end 502 is tightly bounded by the internal passageway of the valve body 3.
The inclusion of the particular valve body 3 embodiments in combination with the ink viscosities described herein have yielded surprising results and improved performance over known ink-dispensing art brushes. The inventors have found that the use of a vented valve body 3 in combination with lower viscosity inks, such as inks having a viscosity of less than 5 cps, such as in the known Art-Kure brush previously described herein, allow thin ink to flow in an unchecked and uncontrolled manner around and along the peripheral axial edges of the bristle assembly 4, as well as into the nozzle portion 2 where it can leak through the threaded end adjacent the body portion 10 and/or leak out between the nozzle 2 and the valve body 3 adjacent the distal end 403. Thus known ink-dispensing brushes allow low viscosity inks to freely flow out the sides of the bristle and nozzle assemblies, and connections therebetween resulting in an uncontrolled and undirected flow of ink that yields poor control of the ink flow by a user, and further allows ink splatter upon squeezing of the reservoir. The lack of a solid valve body in known brushes also means that thin ink is not directed uniformly through and between the bristles, which keeps the bristles from being uniformly saturated, and also prevents the bristles from otherwise serving as a flow regulator.
The inventors have further discovered that the proper combination of higher viscosity inks with the vented valve body 3, or lower viscosity inks with the unvented valve body 3, respectively, result in self-wicking once the assembly is initially primed by a user exerting squeezing pressure on the reservoir body 10. As shown in
Further, the relative diameters of the bristle assembly 4 relative to the inner diameter of the valve body 3 are important to control ink flow, particularly in the unvented embodiment of valve body 3 in combination with thin inks. Preferably, any circumferential gap formed between those two elements is less than about 0.1 to 0.5 millimeters, corresponding to a relative difference in diameter of between about 0.2 to 1.0 millimeters. This relationship is particularly crucial to ease of use of the device, proper ink flow, ink control & splatter when using thin inks of less than about 8 cps. This dimension is also important for proper wicking, and self-wicking, of the ink through the bristles of the bristle assembly 4.
As shown in
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The relative volumes of tubes 11 and 12 are important to the optimal control of ink flow in response to user squeezing pressure exerted on the reservoir body 10 when the art instrument is activated and fully assembled. In particular, the inventors have discovered that an internal volume ratio of tube 11 to tube 12 of about 3:4 provides optimum controllable flow, and further promotes self-wicking in combination with either of the valve body 3 embodiments previously described herein. In contrast, the known Art-Kure brush utilizes a nearly 1:1 volume ratio between the inner capillary tube and outer capillary tube, in combination with a slotted valve body and an ink of less than 5 cps, resulting in undesirable fast flow and spurting of ink from the bristle assembly. Furthermore, the inventors have discovered that the relative volumes of the outer tube 12 and reservoir body 10 help to optimally control ink flow. Preferably, the ratio of the volume of the reservoir body 10 to the volume of the outer tube 12 is at least about 15:1, and more preferably greater than about 18:1.
Lastly,
As shown in
Having recited the various components of the art instrument in a first and second embodiment, we will now explain how the components interact to commence and control liquid flow when the assembled paintbrush is activated. The initial assembly by the manufacturer includes the insertion of the end 1306 of the plug 13 into the second end 1206 of the outer capillary tube 12. Next, the inner capillary tube 11 is inserted into the open end 1202 of the outer capillary tube 12 until the end 1106 rests against the plug end 1306, with the plug end 1306 having irregular external surface geometry such as a recessed slot to ensure flow of liquid from the channel 1308 into the axial channels 1108, 1208 of the inner tube 11 and the outer tube 12. Next, the protruding end 806 of the pin 8 is inserted into open end 1102 of the inner capillary tube 11. Next, the pin-receiving end 706 of the orifice restrictor 7 is inserted over the opposite end 802 of the pin 8, with the outer diameter of the pin-receiving end 702 simultaneously fitting into the axial channel 1208 of the outer capillary tube. Next, the shipping ring 9 is placed over the threaded end 1002 of the reservoir body 10, the reservoir body 10 is filled with liquid such as watercolor paint, and the capillary tube/restrictor assembly is inserted plug-first into the reservoir body 10 until only the first end 702 of the restrictor 7 protrudes from the open end 1002 of the reservoir body 10. Optionally, the sealing means 14, preferably an O-ring, seals the restrictor 7 to the opening 1002 of body 10. This completes the first sub-assembly.
To assemble the second sub-assembly, the bristle portion 4 is inserted into the valve body 3 so that the capped end 502 securely engages the retaining tabs 412 to permit the tapered end 506 of the bristle assembly 4 to protrude from the end 402 of the nozzle 2. The primary orifice restrictor 6 is placed so that the first end 602 rests against the valve body end 410 of the valve body 3 adjacent the capped end 502 of the bristle portion. Next, the cap 1 is placed over the first end 302 of nozzle 2, and the threaded end 306 of the nozzle 2 is slid over the end 402 of the valve body 3 and bristle portion 4 assembly until the nozzle 2 and cap 1 enclose the entire valve body and bristle assembly.
Finally, the first sub-assembly and second sub-assembly are mated together to form a complete product. This assembly comprises the step of mating the threaded end 1002 of the reservoir body 10 of the first sub-assembly to the threaded end 306 of the second sub-assembly, and threading the two ends 1002, 306 together to sandwich the exposed first end 702 of the secondary orifice restrictor 7 of the first sub-assembly against the exposed protruding end 606 of the primary orifice restrictor 6. However, because of the inclusion of the shipping ring 9, at least one of the threads of the threaded end 1002 is unavailable to the threaded end of the nozzle 2. The length of the protruding end 606 is such that when at least one thread is blocked, the protruding end 606 is prevented from penetrating the axial channel 708 of the secondary restrictor to displace the end 802 of the pin 8, thereby preventing any ink flow from the pin to the axial channel 708 since the end 802 remains in tight contact with the pin-receiving end 706. Thus, no liquid can leave the inner capillary tube 11 and pin 8 while the ring 9 remains in place, such as during shipping.
Upon purchase of the product, the instrument is activated by a user. This is accomplished by disassembling the first sub-assembly from the second sub-assembly by unthreading the nozzle end 306 from the threaded end 1002. The user then removes the ring 9 from the threaded end 1002, and proceeds to re-assemble the two sub-assemblies by threading the end 306 of the nozzle 2 onto the threaded end 1002 of the reservoir body 10. With the ring 9 removed, all threads of the threaded end 1002 are available to mate with the nozzle end 306. Fully mating all threads results in compression that forces the protruding end 606 of the primary orifice restrictor fully into the axial channel 708 of the secondary orifice restrictor 7. In the preferred embodiment, the body 704 and corresponding length of the channel 708 are short enough so that the protruding end 606 of the primary restrictor presses against the first end 802 of the pin, thereby creating a space between the end 808 and the surrounding channel step 710 to permit liquid in the pin 8 to flow into the axial channel 708. The flowing ink then passes through the protruding end 606, through the channel 608 of the primary orifice restrictor, and into and/or around the capped end to reach the bristle portion 4. Once ink flow has thus commenced, a user can control the flow simply by capillary action (slowest flow), or may exert pressure such as by squeezing the reservoir body 10 to obtain faster liquid flow.
Lastly, while the embodiment described herein includes a non-resealable arrangement of the orifice restrictors 6, 7 and pin 8 due to their construction using plastics such as HDPE, it is fully contemplated and conceived by the inventors that use of more flexible and self-resilient materials, such as silicone, rubber, self-healing materials, and spring biasing of the pin 8 to a storage position, and the like, may provide for re-sealing. For example, it is fully contemplated that the pin 8 and restrictors 6, 7 can be paired with one or more spring members that would force the pin end 802 to re-engage the channel step 710 of the secondary restrictor when the shipping ring is re-inserted to block full thread mating between the nozzle end 306 and threaded end 1002. Simply said, insertion of the ring would prevent full tightening, and the spring member would not be fully compressed, and would therefore force the large diameter end 802 of the pin 8 to return to its normal position against the channel step 710, thereby blocking ink flow.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.
The present invention is related to U.S. Provisional Patent Application Ser. No. 60/668,667, filed Apr. 6, 2005, to which priority is hereby claimed, and which application is hereby incorporated by reference as though fully set forth herein.
| Number | Date | Country | |
|---|---|---|---|
| 60668667 | Apr 2005 | US |
