Flow restrictor

Abstract

This invention relates to an apparatus for dispensing a viscous fluid whether in combination, disassembly or assembly. The apparatus comprising a cartridge, reservoir or tube containing the fluid and having an openable or opened outlet structure which, when opened, allows the expression of the fluid from a created outlet aperture. A nozzle is engaged or engageable to the outlet structure and/or cartridge, reservoir or tube whereby fluid expressed from the outlet aperture can subsequently move to and be expressed from the nozzle outlet. The openable or opened outlet structure is adapted to provide on opening at least one outlet aperture having a size of area A; and wherein the nozzle has or is adapted to be cut to provide a nozzle outlet of area B, area B being greater than or equal to area A.

Claims

1. An apparatus for dispensing a viscous fluid, said apparatus comprising: a cartridge configured to contain said viscous fluid and comprising an outlet structure, said outlet structure configured to selectively discharge said viscous fluid from said cartridge; a nozzle configured to be selectively attached to said outlet structure of said cartridge such that said nozzle, when attached to said outlet structure, directs said viscous fluid towards an opening of said nozzle when said viscous fluid is discharged from said outlet structure, said opening having a first cross-sectional area, said nozzle having a circumferential, inwardly-extending ledge disposed on an inner surface of said nozzle; and an insert separate from said outlet structure and said nozzle, said insert having a first end with a circumferential, outwardly extending flange and a second end having an end wall defining an orifice having a second cross-sectional area, said insert, when said nozzle is attached to said outlet structure: (i) having said flange positioned between said ledge of said nozzle and said outlet structure, (ii) having said second end including said orifice positioned within said outlet structure, and (iii) being configured to permit passage of said viscous fluid from said outlet structure into said nozzle through said orifice when said viscous fluid is discharged from said outlet structure; wherein said first cross-sectional area is greater than or equal to said second cross-sectional area; and wherein said nozzle is conical in shape and configured to be selectively adapted to increase said first cross-sectional area by repositioning said opening.

2. The apparatus as claimed in claim 1, wherein said viscous fluid is one or more of: a sealing, grouting, caulking, levelling, joining agent, an adhesive, acid, foam, lotion, paste or gel.

3. The apparatus as claimed in claim 1, wherein said opening of said nozzle is formed by cutting away or otherwise removing a portion of said outlet structure.

4. The apparatus as claimed in claim 1, wherein said second of said insert defines an inner surface and an outer surface, and said inner surface and outer surface comprise a substantially conical or frustoconical shape.

5. The apparatus as claimed in claim 1, wherein an inner surface of said insert comprises a stepped or otherwise progressively reducing cross section.

6. The apparatus as claimed in claim 1, wherein said insert is associable with said nozzle.

7. The apparatus as claimed in claim 1, wherein said outlet structure is configured to be adapted by insertion, within or proximate to said outlet structure, of one of a series of interchangeable inserts, each providing a different sized orifice.

8. The apparatus as claimed in claim 1, wherein said apparatus provides for a reduced pressure differential between viscous fluid in said cartridge and viscous fluid in said nozzle when said viscous fluid is being expressed.

9. The apparatus as claimed in claim 1, wherein said nozzle is openable by cutting or the like to increase the first cross-sectional area.

10. The apparatus as claimed in claim 1, wherein said insert is associable with said nozzle.

11. The apparatus as claimed in claim 1, whereby said viscous fluid expressed from said cartridge experiences a pressure drop across said insert, said pressure drop having a magnitude defined by said second cross-sectional area so that a pressure in said cartridge is greater than a pressure at said nozzle to provide a controlled delivery rate for said viscous fluid, which is then moved to and expressed from said opening of said nozzle of said first cross-sectional area to provide a desired bead width or desired bead delivery.

12. The apparatus as claimed in claim 1, further comprising an auxiliary insert, said auxiliary insert having a first end with a circumferential, outwardly extending flange and a second end having an end wall defining an auxiliary orifice having a third cross-sectional area, said auxiliary insert being selectively interchangeable with said insert; wherein said third cross-sectional area is different from said second cross-sectional area; and wherein said first cross-sectional area is greater than or equal to said third cross-sectional area.

13. An apparatus for dispensing a viscous fluid, said apparatus comprising: a cartridge configured to contain said viscous fluid and comprising an outlet structure, said outlet structure configured to selectively discharge said viscous fluid from said cartridge; and a nozzle configured to be selectively attached to said outlet structure of said cartridge such that said nozzle, when attached to said outlet structure, directs said viscous fluid towards an opening of said nozzle when said viscous fluid is discharged from said outlet structure, said opening having a first cross-sectional area, said nozzle comprising an insert integrated within said nozzle, said insert comprising: a first ledge disposed on an inner surface of said nozzle, said first ledge being circumferential about said inner surface and inwardly extending along a first plane; a frustoconical portion contiguous with said first ledge, said frustoconical portion being circumferential about said first ledge and inwardly extending; and a second ledge contiguous with said frustoconical portion, said second ledge being circumferential about said frustoconical portion and inwardly extending along a second plane substantially parallel to said first plane, said second plane offset from said first plane, said second ledge defining an orifice having a second cross-sectional area; wherein said insert, when said nozzle is attached to said outlet structure, is positioned such that: (i) said first ledge interfaces with said outlet structure, (ii) said frustoconical portion extends into said outlet structure, and (iii) said second ledge is positioned within said outlet structure; wherein said insert is configured to permit passage of said viscous fluid from said outlet structure into said nozzle through said orifice when said viscous fluid is discharged from said outlet structure; wherein said first cross-sectional area is greater than or equal to said second cross-sectional area; and wherein said nozzle is conical in shape and configured to be selectively adapted to increase said first cross-sectional area by repositioning said opening.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) A preferred form of the present invention will now be described with reference to the accompanying drawings in which

(2) FIG. 1 shows a cross sectional view of the top of a cartridge and a nozzle to be assembled by a threaded connection,

(3) FIG. 2 shows a cross sectional view of a cartridge having a flow restricting orifice according to the present invention, said cartridge having a nozzle attachment and being filled with a viscous material to be expressed from the cartridge under the application of external pressure,

(4) FIGS. 3A, 3B and 3C show beads of sealing material having been applied from a cartridge through a nozzle having a 7.5 mm diameter outlet and at the same linear speed of movement of the nozzle relative to the application surface, but each having passed through a different sized restrictor orifice prior to the outlet, each of which additionally illustrate a cross-sectional view as A-A, B-B, or C-C,

(5) FIGS. 4A and 4B show beads of sealing material having been applied from a cartridge through a nozzle having a 5 mm diameter outlet and at the same linear speed of movement of the nozzle relative to the application surface, but each having passed through a different sized restrictor orifice prior to the outlet, each of which additionally illustrate a cross-sectional view as D-D or E-E,

(6) FIG. 5 shows a flow restricting assembly of the present invention having a separate and possibly removable or interchangeable insert to provide a flow restricting orifice,

(7) FIG. 6 shows another embodiment of the flow restricting assembly wherein the orifice is integral to the nozzle component,

(8) FIG. 7 shows a cartridge having a conical surface about the top of the outlet region which can be cut to provide a range of different restrictor orifice sizes,

(9) FIG. 8 shows a cartridge having a series of stepped protrusions about the top of the outlet region which can be accurately cut to provide a range of different restrictor orifice sizes,

(10) FIG. 9 shows a nozzle component having a series of snap off restrictor inserts to be used as part of an assembly of the current invention,

(11) FIG. 10 shows another embodiment of the flow restricting assembly having a separate and possibly removable or interchangeable insert to provide a flow restricting orifice,

(12) FIG. 11 shows yet another embodiment of the flow restricting assembly wherein the orifice is integral to the nozzle component.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(13) The present invention is a component or an assembly of components which can be used in conjunction with a cartridge, container or tube 1 containing a viscous material, wherein the cartridge, container or tube 1 allows for the material to be expressed under the application of external pressure, either by a ram or trigger mechanism (for example as seen on a silicone cartridge) 13 or by some other direct or indirect transmission of force (for example a squeezable bottle or tube). The application of pressure may be continuous or semi-continuous, but in some instances could be cyclical or non-continuous.

(14) Generally such cartridges, containers and tubes are supplied in a sealed state (as shown in FIG. 1) to prevent air from reaching their contents. The opening through which the material is to be expressed will be created immediately prior to use with the aid of a readily available implement such as a knife, hacksaw or drill, for example by cutting along line 2. Alternatively there may be a lid or cap which can be removed to create the opening. For example, there may also be a frangible or rupturable film or membrane removable by a user or removable on application of the external pressure, such that an outlet aperture of a pre-determined size is provided.

(15) It is envisaged that a separate nozzle piece 3, able to be attached to the outlet region by a threaded connection 4 (as shown in FIG. 1) or other type of connection, will be provided along with the cartridge 1 to aid in the application of the viscous material. In yet other embodiments, such a nozzle piece 3 may be an integral part of a cartridge, reservoir or tube 1.

(16) Some examples of some of the types of viscous material toward which the invention is directed are silicone, epoxy, polyurethane and other viscous adhesive, caulking, sealing, grouting, levelling or joining agents, liquids, acids, foams, lotions, gels and pastes. These agents are widely available in the types of cartridges, containers and tubes described above.

(17) The main features of a preferred embodiment of the present invention are as shown in FIG. 2. The viscous material 5 will be ejected from the cartridge 1 through outlet region 6, and will then encounter a flow restricting orifice 7 before flowing through into a conical nozzle region 8. The material will then be ejected through the nozzle outlet 9 and form a bead 10 under a continuous or substantially continuous pressure.

(18) The cross sectional area of the nozzle outlet 9 should be the same size as, or larger than that of the flow restricting orifice 7. Preferably both the nozzle outlet 9 and the restricting orifice 7 are circular in shape, however this need not be the case.

(19) Because the flow of the material is restricted before it gets to the nozzle region 8, it is easier to control the formation of the bead 10 at the nozzle outlet 9. For a given linear speed of movement of the nozzle relative to the application surface, the bead 10 which comes out of the nozzle outlet 9 will be thinner and more even than if no flow restrictor had been used. This results in less wastage of the viscous material 5, better application control and, where applicable, more even drying and/or bonding of the viscous material. The bead will be continuous along the length of the join or surface rather than being intermittent in parts.

(20) The thin, continuous bead is particularly advantageous in adhesive dispensing applications where a pressure sensitive adhesive is being used. The consistency of the bead ensures an even bond pressure and allows the mating surfaces to be evenly wet out for sufficient bonding in all regions of the bead.

(21) Another advantage to the restrictor is that there is less pressure inside the nozzle at the outlet 9. The material will not continue leaking from the outlet 9 after the user has stopped actively applying pressure to the cartridge 1 due to pressure build up in the nozzle.

(22) Beads of silicone, all applied at approximately the same linear speed of movement of the nozzle relative to the application surface, but using different sized nozzle and restrictor combinations are shown in FIGS. 3 and 4.

(23) FIG. 3A shows a strip of sealing agent which has been applied through a nozzle opening 9 of 7.5 mm in diameter from a cartridge having an 8 mm diameter outlet region 6 and no restrictor. An illustrative cross section is also shown. FIG. 3B shows a strip applied through the same sized nozzle outlet 9, but wherein a 5 mm restrictor orifice 7 has been placed at the outlet region 6. An illustrative cross section is also shown. It can be seen that a thinner, smoother and more uniform bead 10 has been achieved with the use of the restrictor. Similarly, use of a 2.5 mm diameter restrictor orifice 7 gives an even thinner and more easily controllable bead 10 as shown in FIG. 3C (illustrative cross section also shown).

(24) A similar difference can be seen when comparing FIG. 4A, which shows a bead 10 applied through a 5 mm diameter nozzle outlet 9 in the absence of a restrictor and FIG. 4B which shows a bead 10 applied through the same outlet 9 with a 2.5 mm diameter restrictor orifice 7. Illustrative cross sections are also shown alongside the respective beads. In some cases the restrictor orifice 7 and the nozzle outlet 9 may have the same diameter, but there will still be some utility in this arrangement because the restrictor will reduce the pressure behind the nozzle outlet 9 so that the flow is easier to control.

(25) The flow restricting orifice 7 may be integral to the shape of the outlet region 6 of the cartridge 1, or may be provided by way of a separate insert 11 which is fitted between the conical nozzle 8 and the outlet region 6 of the cartridge 1. An example of how this might be assembled is shown in FIG. 5. In the embodiment shown in FIG. 5, the cross-sectional area F of the flow restricting orifice 7 is greater than the cross-sectional area G of the conical nozzle component 8. Another example of how this might be assembled is shown in FIG. 6. Alternatively, the restrictor orifice 7 could be integral to the conical nozzle component 8, as shown in FIG. 6. In further embodiments the restrictor component may be associated with the nozzle in such a way as to be removable or interchangeable. One or more such flow restricting components (e.g. a nozzle) may be provided to together provide for an outlet or aperture of a pre-determined cross-sectional area, such that the outlet through which a fluid is expressed into a nozzle is of equal or lesser size than the size of the outlet from the nozzle from which the fluid is expressed. Other examples of how this might be assembled are shown in FIG. 10 and FIG. 11. In the embodiments shown in FIG. 10 and FIG. 11, the cross-sectional area F of the flow restricting orifice 7 is less than the cross-sectional area G of the conical nozzle component 8.

(26) The size of the nozzle outlet 9 can be varied by cutting the conical nozzle 8 at different distances from its apex in order to achieve the desired bead size.

(27) The size of the bead 10 required, and in particular its cross sectional width, will depend upon the application. For example, plumbing applications may call for a thicker bead than grouting or tiling applications. For this reason the nozzle 8 may be supplied with a reasonably narrow aperture at its apex (or no aperture), so that the user can cut the nozzle outlet 9 to size as needed. The present invention envisages that the size of the restrictor orifice 7 be similarly adjustable by way of cutting or snapping off portions of the outlet region 6 in order to achieve a restrictor of dimensions which are appropriate and/or optimal given the chosen size of the nozzle outlet 9.

(28) The first way in which such an adjustable restrictor orifice 7 can be provided is, as shown in FIG. 7, to add (integrally or as a separate component) a conical or substantially conical surface 12 to a cylindrically protruding outlet region 6 of the cartridge 1. This surface 12 can then be cut at varying distances from the apex to give the desired orifice diameter. There may be markings 14 or other indicators to assist in locating the cut.

(29) In another embodiment the cartridge 1 is provided with a series of concentric cylindrical protrusions 15 as shown in FIG. 8. These protrusions 15 can be cut off or otherwise removed according to the size of the orifice 7 required. Again, notches 16 or other profile features may assist in locating the cut.

(30) A further alternative, shown in FIG. 9, is to provide, perhaps moulded as part of the conical nozzle, or perhaps as a separate component, a series of snap off inserts 17 each having a different sized orifice 7. The inserts can be used, interchanged, disposed of and replaced as necessary.

(31) For typical sealing and adhesive cartridges it is convenient to provide restrictors which can provide 2.5 mm, 5 mm and 7.5 mm or 8 mm restrictor orifice sizes. For other cartridges, containers and tubes the size range and increments will vary depending on the application.

(32) The foregoing description of the invention includes preferred forms thereof. Modifications may be made thereto without departing from the scope of the invention.