WO2012161710A1

WO2012161710A1 - Fluidic membrane

Info

Publication number: WO2012161710A1
Application number: PCT/US2011/037940
Authority: WO
Inventors: William Jon Rittgers; Bryan Murphy; Eduardo Macias; Odhran Hendley; Michael Mulloy
Original assignee: Hewlett-Packard Development Company, L.P.
Priority date: 2011-05-25
Filing date: 2011-05-25
Publication date: 2012-11-29
Also published as: TW201247431A

Abstract

A fluid holding arrangement arranged to hold fluid by capillary action and a fluidic membrane at a distance from the fluid holding arrangement are disclosed.

Description

Title: Fluidic membrane Background

When a fluid cartridge is connected to a connector, for example of a fluid dispensing device, a fluidic connection is established between the cartridge and the connector to allow fluid to flow out of the fluid cartridge through the connector. Some fluid cartridges store fluid in capillary material, so that a pressure in the fluid cartridge can be regulated with the aid of capillary action. Brief description of the drawings

For the purpose of illustration, certain examples of the present invention will now be described with reference to the accompanying drawings, in which:

Fig. 1 shows an example of a fluid assembly including a fluid cartridge and a fluid dispensing device;

Fig. 2 shows an example of a fluid cartridge;

Fig. 3 shows the example of the fluid cartridge 2 in a different state;

Fig. 4 shows another example of a fluid cartridge;

Fig. 5 shows the example of the fluid cartridge of Fig. 4 in a different state;

Fig. 6 shows a diagram of an example of an abutment membrane in a bottom view;

Fig. 7 shows a diagram of a cross-section A-A of the abutment membrane of Fig. 6 in a side view;

Fig. 8 shows an example of a method of connecting a fluid cartridge;

Fig. 9 shows an example of a method of connecting and disconnecting a fluid cartridge.

Detailed Description

In the following detailed description, reference is made to the accompanying drawings. The examples in the description and drawings should be considered illustrative and are not to be considered as limiting to the specific example or element described. Multiple examples may be derived from the following description and/or drawings through modification, combination or variation of certain elements. Furthermore, it may be understood that also examples or elements that are not literally disclosed may be derived from the description and drawings by a person skilled in the art.

Fig. 1 shows an example of a fluid assembly 1 of a fluid cartridge 2 and a fluid dispensing device 3. The fluid cartridge 2 comprises a reservoir 4 for holding the fluid, and a fluid outlet 5 for transporting the fluid out of the reservoir 4. The fluid dispensing device 3 comprises a dispensing head 6 for dispensing the fluid, for example on a substrate 7 extending along the dispensing head 6. The fluid dispensing device 3 includes a connector 8 for fluidically connecting the fluid dispensing device 3 with the fluid cartridge 2. The connector 8 protrudes from the fluid dispensing device 3 for insertion in the fluid cartridge 2. The connector 8 and the outlet 5 may be arranged to interconnect. For example, the outer diameter of the connector 8 corresponds with the inner diameter of the outlet 5 so that the connector 8 may slide into the outlet 5. In operation, fluid may flow from the outlet 5 to the connector 8, to the dispensing head 6. Fluidic channels 12 may be provided for guiding the fluid from the connector 8 to the dispensing head 6. For example, the channels may include tubes and/or rooms or the like.

In an example, the fluid is a liquid. In a further example, the fluid dispensing head 6 comprises nozzles, and is arranged to eject the fluid out of its nozzles by using piezo-resistors or thermal resistors. In again a further example, the fluid dispensing device 3 is a printer. The fluid may include water, ink, dye, coating or the like. The substrate 7 may comprise print media. In another illustrative example, the fluid dispensing device 3 is a fluid administration device, wherein the substrate 7 may include tissue. In again other examples, fluids may include soap, deodorant, or any other suitable type of fluid. In Fig. 2, an example of a fluid cartridge 2 is shown. In the shown example, the fluid cartridge 2 is disconnected from the fluid dispensing device 3. The fluid cartridge 2 includes a fluid holding arrangement 9. The fluid holding

arrangement 9 is arranged to hold the fluid by capillary action. The fluid holding arrangement 9 may include capillary material such as foam that is adapted to hold the fluid by capillary action. The fluid holding arrangement 9 may be provided in the reservoir 4. The fluid holding arrangement 9 provides for a suitable backpressure regulation in the cartridge 2, both in a connected and disconnected state of the cartridge 2 with respect to the dispensing device 3.

The cartridge 2 includes a fluidic membrane 10. The fluidic membrane 10 is arranged to allow fluid to pass through in a connected state of the cartridge 2. The fluidic membrane 10 is provided in or near the outlet 5, at a distance D from the fluid holding arrangement 9, forming a gap 15 between the fluidic membrane 10 and the fluid holding arrangement 9. The distance D between the fluid holding arrangement 9 and the fluidic membrane 10 is such that the fluidic membrane 10 is hydraulically disconnected from the fluid holding arrangement 9, in a disconnected state of the fluid cartridge 2, as shown in Fig. 2. This may prevent undesired transfer of fluid. One example of selecting a minimum distance D is explained with reference to Figs. 6 and 7. In certain examples, the distance D may be approximately 1 millimeter or more, approximately 5 millimeter or more, or approximately 10 millimeter or more. The gap 15 may comprise air or another suitable gas or substance that allows the fluidic membrane 10 to travel through, while preventing fluid transfer between the fluidic membrane 10 and the fluid holding arrangement 9 in a disconnected state. In one example, the gap 15 and the fluidic membrane 10 may prevent leaking of fluid during or after

disconnection of the cartridge 2.

Fig. 3 shows the fluid cartridge 2 of Fig. 2 wherein the fluidic membrane 10 is partly moved into contact with the fluid holding arrangement 9 by the connector 8. The fluidic membrane 10 is stretched. The fluidic membrane 10 is pushed in the direction F across the gap 15.

In an example, the connector 8 includes a filter 11. The filter 11 is arranged to draw fluid from the fluid holding arrangement 9 when a hydraulic link is established between the fluid holding arrangement 9 and the filter 11. A hydraulic link may be established when the fluidic membrane 10 contacts the fluid holding arrangement 9 on one side, and the filter 11 on the opposite side. During hydraulic connection between the fluidic membrane 10 and the fluid holding arrangement 9, the fluid that is held in the fluid holding arrangement 9 by capillary action may wet the fluidic membrane 10 until a hydrostatic equilibrium is obtained. In turn, the fluid in the fluidic membrane 10 may wet the filter 11 until a hydraulic equilibrium is obtained.

In one aspect of this disclosure, the fluid holding arrangement 9, the gap 15 and the fluidic membrane 10 form part of a fluidic interface 16 that may be applied in any device for interfacing with interconnecting other devices, such as a fluid dispensing devices 3. The fluidic interface 16 may be used for providing and regulating fluid flow between interconnecting devices. The fluidic interface 16 may be useful for different types of fluidic applications.

Figs. 4 and 5 illustrate further examples of a fluid cartridge 2 and a connector 8, in a disconnected and a connected state of the fluid cartridge 2 with respect to the connector 8, respectively. The shown example fluid cartridge 2 is provided with a fluid holding arrangement 9 that includes capillary material 14 and an abutment membrane 13. The capillary material 14 may comprise capillary channels. The capillary material 14 may be arranged to retain fluid, such as liquid, by capillary action. The capillary material 14 may comprise a block of foam, a sponge, textile, cellulose, etc. In a disconnected state of the cartridge 2, the abutment membrane 13 abuts the capillary material 14. In an example, the capillary material 14 wets the abutment membrane 13 until a hydrostatic equilibrium is obtained in the capillary material 14 and the abutment membrane 14. In a hydraulically connected state of the cartridge 2, the abutment membrane 13 at least partly contacts the fluidic membrane 10 so that the abutment membrane 13 in turn wets the fluidic membrane 10 until a hydrostatic equilibrium is reached. The abutment membrane 13 is arranged to fluidically interface with the fluidic membrane 10 and the capillary material 14. The abutment membrane 13 is arranged opposite to the fluidic membrane 10 and at said distance D from the membrane 10. The gap 15 is provided between the fluidic membrane 10 and the abutment membrane 13. The fluidic membrane 10 is arranged to stretch into contact with the abutment membrane 13. The connector 8 pushes the fluidic membrane 10 against the abutment membrane 13 during which the fluidic membrane 10 stretches. A hydraulic connection can be established between the capillary material 14 and the filter 11, through the fluidic membrane 10 and the abutment membrane 13.

In an example, the abutting membrane 13 is relatively rigid while the fluidic membrane is relatively flexible. In an example, the abutting membrane 13 is at least more rigid than the fluidic membrane 10. A certain rigidness or stiffness of the abutting membrane 13 may prevent deformation of the abutting membrane 13 and/or the capillary material 14 when contacted and/or pushed by the fluidic membrane 10.

The membrane 10 is flexible to allow for further stretching. The fluidic membrane 10 may include elastomeric or resilient material. In an example, the fluidic membrane 10 comprises a web structure. For example, the fluidic membrane 10 may comprise fibers, cloth, fabric, tissue, or the like. The fluidic membrane 10 may comprise capillary material.

For example, in a connected and stretched state of the fluidic membrane 10, the pores and/or channels in the fluidic membrane 10 may increase in size to facilitate higher fluid permeability. For example, in a disconnected state of the fluidic membrane 10, pores and/or channels through the fluidic membrane 10 are relatively small to inhibit fluid transfer and/or decrease fluid permeability. In an example, inner walls 17 in the outlet 5, between the fluidic membrane 10 and the fluid holding arrangement 9 comprise a hydrophobic surface (see Fig. 4). For example, the inner walls 17 of the gap 15 are hydrophobic, to prevent that fluid remains in the gap 15 after disconnecting the cartridge 2. In a further example, the abutting membrane 13 is hydrophilic so that it may be properly saturated with fluid by the capillary material 14 up until hydrostatic equilibrium is reached and/or to facilitate fluid transfer during connection of the cartridge 2. In again a further example, the fluidic membrane 10 is hydrophilic to facilitate fluid transfer. In again further examples, the membranes 10, 13 may be relatively hydrophobic on the side facing the gap 15 and/or relatively hydrophilic on the opposite side. Surface treatment techniques may be applied, such as plasma treatment, to obtain the hydrophobic and/or hydrophilic properties of the respective portions. If the fluidic membrane 10 and/or the abutment membrane 13 have a hydrophobic surface on the respective side facing the gap 15, this may facilitate keeping the gap 15 free of fluid, and/or further prevent a hydraulic connection between the membranes 10, 13 in a disconnected state of the cartridge 2. The influence of the hydrophobic properties of the respective surfaces of the membranes 10, 13 may be reduced or nullified once the membranes 10, 13 interconnect so that fluid passes. In one example, a minimum distance D between the two membranes 10, 13 may be determined by an effective height h of a meniscus 19 that extends from a bottom 20 of the abutment membrane 13, as is illustrated by the examples of Fig. 6 and 7. The effective height h of the meniscus 19 may depend on an effective size of a respective aperture 18 in the abutting membrane 13. The aperture 18 may be a channel or pore through which the fluid passes. As will be understood, while the shown aperture 18 is circular, and diagrammatic and theoretical of nature, in practice such aperture 18 could be of any shape. Hence, the referenced heights and radii will be referred to as effective heights and radii.

The abutting membrane 13 includes at least one aperture 18. The aperture 18 has an effective radius Ra. The meniscus 19, extending from the bottom 20, has an effective radius Rm. In theory, these effective radii Ra, Rm may determine an effective height h of the meniscus 19 according to the following equation:

Rm² = Ra² + (Rm - h)²

An effective height that the meniscus 19 will project from the bottom 20 of the abutment membrane 13 may be stated as: h = Rm - (Rm² - Ra²)^1/2

This can be restated using the contact angle Θ to eliminate the effective meniscus radius Rm or effective aperture radius Ra using the following equations:

Rm = Ra-Cos Θ or Ra = Rm / Cos Θ

For example, to prevent that the meniscus 19 contacts the fluidic membrane 10, the distance D (or height of the gap 15) may be greater than the maximum height h of a meniscus 19 that is formed on the bottom of the abutment membrane 13, for example corresponding to a maximum effective aperture radius Ra. The distance D may be chosen according to the particular fluid holding arrangement

9 and/or abutment membrane 13 and/or fluid. Note that in other examples of this disclosure, no abutment membrane 13 is provided, and the meniscus 19 may extend from a bottom of the fluid holding arrangement 9, and similar principles apply.

Fig. 8 shows a flow chart of an example of a method of connecting a fluid cartridge 2. The method may include holding fluid in the fluid holding

arrangement 9 by capillary action (block 600). At a point where the fluid cartridge 2 is not connected, the fluidic membrane 10 is disconnected from the fluid holding arrangement 9. Hence, no fluid flows from the cartridge 2. The method may further include pushing a connector 8 against the fluidic membrane

10 (block 610). Here, at least a part of the connector 8 may be inserted in the outlet 5. The method may include moving the fluidic membrane 10 at least partly into contact with the fluid holding arrangement 9 (block 620), as may be provoked by the insertion of the connector 8. The method may include fluid flowing from the fluid holding arrangement 9 to the connector 8 through the fluidic membrane 10 (block 630), in a connected state. The fluid may flow through the fluidic membrane 10 when the fluidic membrane 10 at least partly contacts both the fluid holding arrangement 9 and the connector 8 until a hydrostatic equilibrium is reached.

Fig. 9 shows flow chart of another example of a method of connecting a fluid cartridge 2. The method may include holding fluid in the capillary material 14 and the abutting membrane 13 by capillary action (block 700). The abutting membrane 13 abuts the capillary material 14 so that they are hydraulically connected. The abutting membrane 13 is wetted by fluid from the capillary material 14 until a hydrostatic equilibrium. The method may further include pushing the fluidic membrane 10 with the connector 8 (block 710) so that at least a part of the fluidic membrane 10 travels across the gap 15. The connector 8 moves the fluidic membrane 10 during insertion of the connector 8. The connector 8 includes a filter 11. As the connector 8 pushes the fluidic membrane 10, the fluidic membrane 10 is stretched (block 720) to allow the connector 8 to extend further into the outlet 5, until further movement may be inhibited by the rigid abutting membrane 13. The fluidic membrane 10 is flexible to allow it to stretch until it contacts the abutting membrane 13 (block 730).

Fluid may flow to the fluidic membrane 10 when the fluidic membrane 10 at least partly contacts the abutting membrane 13 (block 740), reaching a hydrostatic equilibrium. In addition, the fluid is transferred to the filter 11 (block 750) when the fluidic membrane 10 contacts the filter 11 and the abutting membrane 13, reaching a hydrostatic equilibrium. Consequently, fluid may be delivered to further channels 12 and/or the dispensing head 6.

The method may further include disconnecting the cartridge 2 (block 760), so that the hydraulic connection is broken. The fluidic membrane 10 may return to its initial position, out of contact with the abutment membrane 13, and reestablishing the gap 15. The fluidic membrane 10 may hydraulically disconnect from at least one of the abutment membrane 13 and the connector 8 (block 770) so that the flow of fluid through the fluidic membrane 10 stops. For example, while the connector 8 retreats, first the fluidic membrane 10 is disconnected from the abutment membrane 13, breaking the link with the capillary material 14. For example, left over fluid in the fluidic membrane 10 is soaked by the filter 11. Then, the connector 8 is fully disconnected from the fluidic membrane 10. After disconnection, the gap 15 prevents that fluid flows out of the fluid holding arrangement 9. In one example, the gap 15 and the fluidic membrane 10 may prevent leakage of fluid during or after disconnection of the cartridge 2. In a further example, the gap 15 remains substantially free of fluid after

disconnection.

In an aspect of this disclosure, a fluidic interface 16 is provided. The fluidic interface 16 may include a fluid holding arrangement 9 comprising capillary material 14 for holding fluid. The fluidic interface 16 may include a fluidic membrane 10. The fluidic interface 16 may include a gap 15 between the fluid holding arrangement 9 and the fluidic membrane 10 to prevent flow of fluid from the fluid holding arrangement 9 to the fluidic membrane 10, wherein the fluidic membrane 10 may be arranged to at least partly travel across the gap 15 for at least partly contacting the fluid holding arrangement 9 to allow the fluid to flow from the fluid holding arrangement 9 to the fluidic membrane 10 during contact.

In an example, the fluidic membrane 10 is arranged to slide in the outlet 5, towards and away from the fluid holding arrangement 9, in addition to or instead of being stretched. In a further example, the fluid holding arrangement 9 may include a coating or the like near the outlet 5, in addition to or instead of the abutment membrane 13, for contacting the fluidic membrane 10 during hydraulic connection. The coating may locally rigidify or stiffen the fluid holding arrangement 9.

The above description is not intended to be exhaustive or to limit this disclosure to the examples disclosed. Other variations to the disclosed examples can be understood and effected by those skilled in the art from a study of the drawings, the disclosure, and the claims. The indefinite article "a" or "an" does not exclude a plurality, while a reference to a certain number of elements does not exclude the possibility of having more or less elements. A single unit may fulfil the functions of several items recited in the disclosure, and vice versa several items may fulfil the function of one unit. Multiple alternatives, equivalents, variations and combinations may be made without departing from the scope of this disclosure.

Claims

1. Fluid cartridge, comprising

a fluid holding arrangement arranged to hold fluid by capillary action, a fluid outlet, and

a fluidic membrane, wherein

the fluidic membrane is

provided in the outlet, at a distance from the fluid holding arrangement so that it is hydraulically disconnected from the fluid holding arrangement in a disconnected state of the fluid cartridge, and

arranged to be at least partly moved into contact with the fluid holding arrangement in a connected state of the fluid cartridge so that a hydraulic connection is established between the fluidic membrane and the fluid holding arrangement.

2. Fluid cartridge according to claim 1, wherein the fluidic membrane is arranged to stretch to at least partly contact the fluid holding arrangement.

3. Fluid cartridge according to claim 1, wherein the fluid holding

arrangement comprises

capillary material for holding the fluid, and

an abutting membrane abutting the capillary material for contacting the fluidic membrane in said connected state.

4. Fluid cartridge according to claim 3, wherein the abutting membrane is more rigid than the fluidic membrane to prevent deformation of the abutting membrane when the fluidic membrane at least partly contacts the abutting membrane.

5. Fluid cartridge according to claim 1, wherein in a disconnected state of the fluid cartridge the distance between the fluidic membrane and the fluid holding arrangement is at least 1 millimeter.

6. Fluid cartridge according to claim 1, wherein in a disconnected state of the fluid cartridge the distance between the fluidic membrane and the fluid holding arrangement is larger than a calculated maximum height of a meniscus extending from a bottom of the fluid holding arrangement.

7. Fluid cartridge according to claim 1, wherein the fluid comprises ink.

8. Fluid cartridge according to claim 1, wherein inner walls in the outlet, between the fluidic membrane and the fluid holding arrangement, comprise a hydrophobic surface.

9. Fluid assembly of a fluid cartridge according to claim 1 and a fluid dispensing device, the fluid dispensing device comprising

a dispensing head for dispensing the fluid,

a protruding connector arranged to

be inserted into the fluid outlet, and

guide the fluid from the fluid cartridge to the dispensing head, wherein the connector and fluidic membrane arranged so that, when connecting the fluid cartridge, the connector pushes the fluidic membrane at least partly into contact with the fluid holding arrangement.

10. Assembly according to claim 9, the connector comprising a filter, arranged so that in a connected state of the fluid cartridge, the fluid holding arrangement, the fluidic membrane and the filter are hydraulically connected.

11. Method of connecting a fluid cartridge comprising a fluid holding arrangement and a fluidic membrane, the method comprising

holding fluid in the fluid holding arrangement by capillary action, pushing against the fluidic membrane,

therewith moving the fluidic membrane at least partly into contact with the fluid holding arrangement, and

fluid flowing from the fluid holding arrangement through the fluidic membrane when the fluidic membrane at least partly contacts the fluid holding arrangement.

12. Method according to claim 11, comprising

disconnecting the fluid cartridge, and

stopping the flow of fluid when the fluidic membrane hydraulically disconnects from the fluid holding arrangement.

13. Method according to claim 11, comprising stretching the fluidic membrane until it at least partly contacts the fluid holding arrangement.

14. Method according to claim 11, the fluid holding arrangement comprises capillary material and an abutting membrane, the method comprising

establishing a hydraulic connection by

holding the fluid in the capillary material and abutting membrane through capillary action,

pushing the fluidic membrane with a connector,

flowing of fluid to the fluidic membrane when the fluidic membrane at least partly contacts the abutting membrane, and

transferring the fluid to the connector when the fluidic membrane contacts the connector and the abutting membrane.

15. Fluidic interface, comprising

a fluid holding arrangement comprising capillary material for holding fluid,

a fluidic membrane, and

a gap between the fluid holding arrangement and the fluidic membrane to prevent flow of fluid from the fluid holding arrangement to the fluidic membrane, wherein the fluidic membrane is arranged to at least partly travel across the gap for at least partly contacting the fluid holding arrangement to allow the fluid to flow from the fluid holding arrangement to the fluidic membrane during contact.