CONTAINER WITH FLOATING VENT TUBE FOR MICRO-FLUID APPLICATIONS

Abstract

A consumable supply item for an imaging device holds an initial or refillable volume of fluid. An interior holds the fluid and users orient a housing to deplete the fluid in a direction of gravity. An air conduit tube fluidly connects to an air port to vent the interior to atmosphere. A float buoyantly supports the tube on a surface of the volume of fluid. It suspends a terminal opening of the tube above the fluid so that as the volume of fluid depletes in the interior over time, or an orientation of the housing is altered during handling, the terminal opening is maintained above the surface of the volume of fluid. Fluid leakage is minimized during transport and manipulation.

Description

FIELD OF THE INVENTION

The present invention relates to micro-fluid applications, such as inkjet printing. The invention relates further to supply item containers holding fluid, but overcoming leakage during times of transportation and abnormal orientation. Floating vent tubes facilitate the embodiments.

BACKGROUND

The art of printing images with micro-fluid technology is relatively well known. A (semi)permanent ejection head has access to a local or remote supply of fluid. The fluid ejects from an ejection zone to a print media in a pattern of pixels corresponding to images being printed.

Upon fluid ejection, containers holding fluid undergo pressure increases. They are vented to atmosphere to equalize the pressure in a variety of ways. Some containers define tortuous paths in body walls to slowly vent air inside. Others have air vent ports that interface with corresponding ports in imaging devices which, in turn, connect to sources of atmosphere. In either, vents provide avenues of fluid leakage from the containers during times of transport, storage, handling and/or manipulation. To prevent leakage, labels/stickers are used to cover paths and caps are plugged into ports that users remove before use. With the latter, however, vent ports are typically located above fluid levels in the container during normal orientation. When imaging devices are moved or suffer abnormal orientation, fluid can exit directly from the vent port causing spillage and endangering hardware. Leakage can also occur outside the imaging device when users handle containers after cap removal.

A need exists in the art to prevent fluid leakage from containers during times of handling or abnormal orientation. The need extends not only to economical solutions, but to simplicity. Solutions should also contemplate the diversity of locations in which vent ports can be placed on containers. Additional benefits and alternatives are also sought.

SUMMARY

The above-mentioned and other problems become solved with containers having floating vent tubes for micro-fluid applications. A consumable supply item for an imaging device holds an initial or refillable volume of fluid. A housing defines an interior to hold the fluid and locates fluid exit and air vent ports. Users orient the housing to deplete the fluid in a direction of gravity. An air conduit tube fluidly connects to the air vent port to vent the interior of the housing with air from outside the housing. A float is buoyantly positioned on a surface of the volume of fluid. It connects to the air conduit tube to suspend a terminal opening of the tube above the fluid so that as the volume of fluid depletes in the interior over time or an orientation of the housing is altered during handling, the terminal opening is maintained above the surface of the volume of fluid. Fluid leakage is minimized during handling and transport. Relationships are noted between the tube and the float as well as locations of the ports on the housing. A hydrophobic membrane defines still other embodiments.

These and other embodiments are set forth in the description below. Their advantages and features will become readily apparent to skilled artisans. The claims set forth particular limitations.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the embodiments and together with the description serve to explain the guiding principles herein. In the drawings:

FIG. 1A is a diagrammatic view of a container with a floating vent tube;

FIG. 1B is a view similar to FIG. 1 with a floating vent tube at a lower fluid level;

FIGS. 2A and 2B are views showing various container orientations;

FIG. 3 is a view showing an alternate placement of air vent ports for a container;

FIGS. 4A and 4B are views showing accessories for a float supporting an air conduit tube;

FIG. 4C is a view showing an alternate air conduit tube; and

FIGS. 5A and 5B are views according to the prior art showing fluid leakage from a container having no floating vent tube.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

In the following detailed description, reference is made to the accompanying drawings where like numerals represent like details. The embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the invention. The following detailed description, therefore, is not to be taken in a limiting sense and the scope of the invention is defined only by the appended claims and their equivalents. In accordance with the features of the invention, containers have floating tubes venting interiors to atmosphere to overcome leakage for use in micro-fluid applications.

With reference to FIGS. 1A and 1B, a supply item container 10 for use in an imaging device includes a housing 12. The housing defines an interior 14 that contains an initial or refillable supply of fluid, e.g. ink 16. The fluid is any of a variety, but typifies aqueous inks such as those based on dye or pigmented formulations. It also represents varieties of color, such as cyan, magenta, yellow, black, etc. The item is useful in many applications such as inkjet printing, but certainly can be useful with other fluids in medicinal delivery, forming circuit traces, food processing, chemical manufacturing, etc.

During use, the volume of ink depletes downward toward a bottom surface 18 of the interior of the housing in a direction of gravity G. The bottom surface is generally flat or inclined to funnel ink out of the interior. The ink flows to an imaging device by way of a fluid exit port 20. An air venting port 22 provides an intake of ambient, recycled or other air to overcome backpressure in the interior 14 that increases during imaging operations. The ports are any of a variety but typify cylindrical tubes biased shut with an internal ball and spring (not shown). They are mated with a septum needle 30 from the imaging device. The needle inserts into the ports to overcome the bias of the spring and the ball slides backward. Upon sufficient insertion, openings in the port and needle are communicated so that a fluidic channel opens between the interior 14 of the housing and the needle. The fluidic channel is either air or liquid.

Within the interior 14, the air vent port 22 connects to an air conduit tube 50. The tube is flexible and floats in the interior. It has a terminal opening 52 that fluidly connects the interior with air from outside the housing. A float 60 connects to the tube to suspend the terminal opening 52 above a surface 70 of the volume of fluid. As the volume of fluid depletes in the interior over time or as an orientation of the housing is altered, the terminal opening is maintained above the surface of the volume of fluid.

With reference to FIG. 1B, the terminal opening is kept above the fluid as the volume of fluid depletes to a fluid level B from fluid level A (FIG. 1A). (Conversely, the float would rise upon users refilling the container.) While the drop causes the float 60 to drop, it does not cause the float to rotate the terminal opening under the surface 70 of the fluid. Rather, the air conduit tube 50 acts as a tether on the float to prevent this. The interior walls 55 also serve to bound the area of travel in which the float can maneuver.

In FIGS. 2A and 2B, the terminal opening 52 is kept above the fluid as the orientation of the housing 12 is manipulated regardless of whether the air vent port 22 resides above (FIG. 2A) or below (FIG. 2B) the surface 70 of the volume of fluid. This mitigates or solves the problem of the prior art where fluid drops 116′ of ink 116 have been observed to leak from a housing 112 at an air vent port 122 as users move the housing from a proper orientation during use (FIG. 5A) to an alternate orientation (FIG. 5B). With reference to FIG. 3, further embodiments note that the placement of the air vent port 22 can change without compromising the venting of the interior of the housing or implicating fluid leakage. As noted, the air vent port can reside at any of the discrete positions labeled 22-1-22-6 or at any position along the length of any of the walls 55. Its position can be initially beneath or below the surface 70 of the volume of fluid as the housing 12 housing is properly oriented during use to deplete the volume of fluid from the interior. Similarly, the air vent port 22 can be above or below the fluid exit port 20 as the housing is properly oriented during use.

With reference to FIGS. 4A and 4B, accessories to the float 60 may be used to improve the foregoing notions. First, a float can have a counterweight 61 to produce a moment arm that rotates the float in the direction of the arrow 1. The weight/rotation technique ensures positioning the terminal opening 52 in a vertically upright manner. Of course, the weight can be heavier/lighter and/or larger/smaller depending upon how much torque is needed to cause rotation per a given set of conditions. Second, the float 60 can be adorned with a hydrophobic membrane 63 that is permeable to air. While attaching the membrane over the terminal opening 52, the air conduit tube still remains vented to atmosphere and minute drops of fluid are prevented from entering the tube and exiting the air vent port as fluid sometimes sloshes in the interior during times of handling. An undersurface 65 of the membrane can adhere to an exterior surface 67 of the float for proper placement. The membrane is as thin as possible but may define a thickness of at least a few mils. Representative membranes contemplate the use of polytetrafluoroethylene (PTFE) or other materials. Membranes of this type are sometimes referenced as “breather” vents. With reference to FIG. 4C, minute drops of fluid can be alternatively prevented from entering the tube 50 by tapering its remote end 69. In this way, the terminal opening 52 presents a small front to the interior of the housing to minimize entry of small drops of fluid, but does not otherwise affect the ability of the tube to vent the housing. Tube diameters of about 0.1 mm are expected in the vicinity of the terminal opening 52.

In any design, the tube 50 attaches to the float, such as by insertion through an interior channel 69 of the float. In this way the terminal opening 52 of the tube is made coterminous with the exterior surface 67 of the float thereby keeping the terminal opening a sufficient distance away from the surface of the fluid but still allowing the membrane to cover the terminal opening while attaching to the float. Alternatively, the terminal opening is positioned only a portion of the way into the interior channel or positioned to extend well beyond the surface of the float to maximize the distance between the fluid and the opening. Alternatively still, the tube is attached to an exterior of the float, not an interior. In any design, the float 60 may have portions 62 temporarily or permanently suspended under the surface 70 of the fluid. Either is acceptable so long as the terminal opening remains open.

Regardless of design, common constraints for containers are noted. For example, it is expected that the air conduit tube will be formed of a material that is compatible with the fluid of the container over a lifetime of usage and is flexible to move. Polypropylene is one such material and is commercial available under the trade name “Tygon.” A length of the material will vary according to its positioning in the interior relative to the location of the air vent port, but may be set with an initial distance of at least two inches to extend across a length of the container. Otherwise, if the tube is too short, any abnormal orientation of the container might submerge the terminal opening of the tube beneath the surface of the fluid and cause leakage. A diameter of the tube will be largely dictated by the diameter of the air vent port and, in turn, the constraints of the accompanying imaging device that is furnishing the atmospheric conditions.

The float 60 is envisioned as cork or low density Styrofoam. As the volume of the float consumes space within the interior 14 of the container that could be otherwise filled with fluid, a smaller volumetric float is contemplated rather than a larger float to maximize fluid capacity. The float preferably is also of a composition that avoids absorption of fluid, otherwise its intended function might be compromised. Its shape is any of a variety, but spherical is the likeliest of candidates. The float 60 will also likely connect direct to the tube 50, such as by welding, adhesives or mechanical fasteners, or by intermediate structures, such as by connecting rods or wires that hang the tube with its terminal opening in an upward orientation.

The housing itself is any of a variety of containers for holding ink. It can typify plastic, glass, metal, etc. It can be recyclable or not. It can contemplate simplicity or complexity. Techniques for production are varied, but blow molding, injection molding, etc. are common techniques. With blow molding, the housing 12 can be made of unitary construction to define the interior 14. Welding, heat-staking, bonding, dies, etc. are also envisioned. The materials, construction, shipping, storage, use, etc. of the housing can also focus design criteria on items, such as cost, ease of manufacturing, durability, or other. Its shape is nearly infinite. Implicating its selection are good engineering practices such as contemplation of a larger imaging context in which the housing will be used. In the design given, the housing is generally elongated from its back end 39 to its port end 41. The port end inserts forward into an imaging device as the back end is pushed upon by users. The shape also contemplates seals and septums or the like which may find utility in the design at the interface joints between the ports and the imaging device.

The foregoing illustrates various aspects of the invention. It is not intended to be exhaustive. Rather, it is chosen to provide the best illustration of the principles of the invention and its practical application to enable one of ordinary skill in the art to utilize the invention. All modifications and variations are contemplated within the scope of the invention as determined by the appended claims. Relatively apparent modifications include combining one or more features of various embodiments with features of other embodiments.

Claims

1. A container to hold an initial or refillable volume of fluid, comprising:

a housing defining a fluid exit port, an air vent port, and an interior to retain the volume of fluid, the interior being properly oriented during use to deplete the volume of fluid toward the fluid exit port;

an air conduit tube having a terminal opening in the interior of the housing that is fluidly connected to the air vent port to vent the interior with air from outside the housing; and

a float for buoyant positioning on a surface of the volume of fluid, the float connecting to the air conduit tube to suspend the terminal opening above the surface so that as the volume of fluid depletes in the interior over time or an orientation of the housing is altered, the terminal opening is maintained above the surface of the volume of fluid.

2. The container of claim 1, wherein the air conduit tube inserts through an interior of the float.

3. The container of claim 2, wherein the terminal opening of the air conduit tube is coterminous with a surface of the float.

4. The container of claim 1, further including a hydrophobic membrane attached over the terminal opening of the air conduit tube, the membrane being permeable to said air.

5. The container of claim 4, wherein an undersurface of the hydrophobic membrane is adhered to an exterior surface of the float.

6. The container of claim 1, wherein the air vent port of the housing resides beneath the surface of the volume of fluid as the housing is properly oriented during use to deplete the volume of fluid from the interior.

7. The container of claim 6, wherein the air vent port is located above the fluid exit port of the housing as the housing is properly oriented during use to deplete the volume of fluid from the interior.

8. The container of claim 1, further including a counterweight on the float to position vertically upright the terminal opening of the air conduit tube.

9. The container of claim 1, wherein the housing is of unitary construction being blow molded to define the interior.

10. The container of claim 1, wherein the air conduit tube extends for a length of at least two inches in the interior.

11. The container of claim 1, wherein the float includes cork.

12. The container of claim 1, wherein the float includes Styrofoam.

13. The container of claim 1, wherein the air conduit tube tapers at a remote end thereof.

14. The container of claim 13, wherein the terminal opening has a diameter of about 0.1 mm.

15. A container to hold an initial or refillable volume of fluid, comprising:

a housing defining a fluid exit port, an air vent port, and an interior to retain the volume of fluid, the interior being properly oriented during use to deplete the volume of fluid toward the fluid exit port in a direction of gravity;

an air conduit tube having a terminal opening in the interior of the housing that is fluidly connected to the air vent port to vent the interior with air from outside the housing; and

a float for buoyant positioning on a surface of the volume of fluid, the float connecting to the air conduit tube to suspend the terminal opening above the surface so that as the volume of fluid depletes in the interior over time or an orientation of the housing is altered, the terminal opening is maintained above the surface of the volume of fluid,

wherein the air conduit tube inserts through an interior of the float so that the terminal opening resides coterminous with a surface of the float and a hydrophobic membrane attaches over the terminal opening, the membrane being permeable to said air.