EP0105181B1

EP0105181B1 - Apparatus for dispensing fluid compositions

Info

Publication number: EP0105181B1
Application number: EP83108415A
Authority: EP
Inventors: Laurence R. Penn; Steven R. Anderson
Original assignee: LIQUID CONTROL INTERNATIONAL CO
Current assignee: LIQUID CONTROL INTERNATIONAL CO
Priority date: 1982-09-07
Filing date: 1983-08-26
Publication date: 1988-12-14
Also published as: EP0105181A2; EP0105181A3; CA1217745A; JPH0322208B2; DE3378686D1; JPS5973031A; ATE39239T1; DE105181T1

Abstract

Apparatus for dispensing of at least two different fluid compositions, said apparatus comprising: a cartridge (37) having therein plural separate chambers (4, 6) for containing separate fluid compositions to be dispensed; a neck portion (8) provided at a discharging first end of said cartridge; plural separate passageways (10, 12) extending through said neck portion, each said passageway opening into a separate respective said chamber, the arrangement being such that the simultaneous application of pressure to the fluid compositions in each said separate chamber causes, in cooperation with a back pressure from the restriction of said passageways, compression of the fluid compositions, and thus causes the fluid compositions to be extruded in a predetermined ratio through the respective said passageways; and means for controlling the flow of the fluid compositions through the respective said passageways, for preventing run-on of the fluid compositions through said respective passageways due to decompression of the fluid compositions upon removal of the pressure, and thereby for preventing dispensing of the fluid compositions through said respective passageways in a ratio other than said predetermined ratio, said controlling means comprising a valve member (18) having therethrough plural passage portions (22, 24) said valve member being mounted within said neck portion for movement with respective thereto between an open first position, whereat said passage portions are aligned with respective said passageways, thereby permitting extrusion of the fluid compositions through said passageways in said predetermined ratio, and a closed second position, whereat said flow portions are out of alignment with said respective passageways and said passageways are blocked by said valve member, thereby preventing any passage of the fluid compositions through said passageways.

Description

The present invention relates to an apparatus for dispensing fluid compositions and, particularly to apparatus for dispensing, in desired proportions, two different fluid compositions which cure when mixed together and which have different degrees of compressibility.
More particularly, the present invention is directed to such an apparatus suitable for the storage, shipping, proportioning, mixing and dispensing of at least two such different fluid compositions.
Known apparatus for dispensing such fluid compositions suffer from a number of disadvantages. Unlike hydraulic liquids, most single and multi-component adhesives, sealants and mastics contain a certain amount of entrained air which becomes mixed into the composition or compositions during formation or compounding thereof. The level of such entrained air may be tolerated or controlled for technical and commercial reasons. Additionally, some forms of fillers employed in such compositions may be compressible. Examples of such compressible fillers are microglass spheres or balloons. It is known for fluid components to be loaded, for dispensing, into a suitable cartridge. However, air bubbles may be trapped within a cartridge containing the component or components during loading of the component into the cartridge, and such trapped air bubbles may be compressed and expanded during dispensing cycles. The cartridge body may expand and contract due to supported wall clearances or unsupported wall movement.
The result of the above is that, in cooperation with back pressure from a dispensing nozzle, some degree of compression of the component or components takes place during the application of pressure to the component or components to dispense the same from the cartridge. Thus, after the power source for applying a dispensing pressure is removed, the component or components are often seen to "run-on" from the nozzle for a certain period of time while decompression takes place. This run-on may be used up as part of the desired amount of material Being dispensed for a particular operation or may be allowed to run to waste.
Generally, such run-on does not seriously affect the performance of a cartridge for dispensing a single component material, and the characteristic run-on is accepted as being overridden by the benefits of such apparatus.
On the other hand, when dispensing multicomponent or composition materials, the problem of run-on is multiplied and much more complex, and may possibly have damaging results on the chemistry of the multicomposition material.
When proportioning only or when proportioning and mixing plural liquid compositions, such as reactive adhesive systems, from a cartridge, for example a coaxial cartridge arrangement, the chances are high that one fluid composition or material will run-on to a greater or lesser extent than the other compositions or materials. This is due to the factors described above, and additionally due to the fact that the proportioning ratio between the plural compositions add to the likelihood of unequal compres- sion/decompression. Unlike run-on of a single component material, the results of unequal run-on from the materials of a multicomponent material are that the ratio of the plural compositions at some point in time may become incorrect. This causes "off-ratio" patches to be dispensed from the cartridge and mixing device, for example a motionless in-line mixer. The results of numerous tests involving multiple cartridge dispensing of various two component reactive systems have determined that only a few such systems remain within tolerance limits of the desired predetermined ratio of mixture of the two components during the starting and stopping periods of flow, and that most such systems result in "off-ratio" patches, recognisable either visibly or by their performance. Since some specific skill or test procedure would be necessary to control the quality of the mixed composition resulting from the multiple compositions at the starting and stopping points of flow thereof, the benefits of using multiple cartridge dispensing apparatus may be reduced, sometimes to the point of being completely unacceptable in practice. Thus, a user dispensing a long bead of adhesive may scrap the first dispensed volume until a visual color change indicative of a proper predetermined proportional ratio has occurred. However, a lower volume user wishing to start and stop to provide only small spots of a mixed composition might have his production efficiency substantially reduced by off-ratio mixtures. Furthermore, many reactive composition systems are such that a visible color change does not occur between off-ratio and on-ratio mixtures. This further adds to the uncertainty of attempting to determine when the mixture is on-ratio.
This problem may be reduced to some extent by increasing the mixer and nozzle size, thereby reducing the outlet back pressure. However, large mixers and nozzles generally are not desirable in this type of system.
A more specific explanation of the problem is as follows. In a two component or composition cartridge system the application of pressure to achieve dispensing causes the less compressible material to start flowing through the mixer before the second material, i.e. while the second material is still being compressed. As the compression of the second, more compressible material is increased, the flow thereof increases to a point where the two materials flow through the mixer in a desired predetermined ratio. Therefore, after an initial off-ratio mixture, having a high proportion of the less compressible material, the mixed composition becomes correct. As soon as the dispensing pressure is removed the less compressible, more hydraulic, material ceases to flow relatively quickly, while the more compressible, less hydraulic material continues to flow, i.e. to run-on. At this point, the more compressible, less hydraulic, composition predominates in the mixed composition, and the extent of this pre- domination is substantially equal to the volume of the more compressible material which should have been mixed with the less compressible material during the initial starting operation to achieve the desired predetermined proportional ratio. This stopping or final run-off is off-ratio. Assuming that the unit is at rest for a period of time to allow complete decompression to take place, it is likely that the mixer will contain an incorrectly high proportion of the more compressible, less hydraulic composition. Therefore, when pressure again is applied to commence dispensing, a mixture having a high proportion of the more compressible component will initially be discharged, and this will be followed by the discharge of a mixture having a high degree of the less compressible component. The above sequence of events will be repeated during each dispensing cycle, with the exception that upon continued use, the reduced volumes left within the chambers of the cartridge will cause a reduction in the extent of compression/ decompression. Economic cartridge sizes are such that the volumes always will be high enough to reflect the above discussed occurrences of off-ratio mixtures.
It will thus be appreciated that it is desirable in an apparatus for dispensing at least two different fluid compositions that the apparatus be operable in such a manner that flow can be stopped and started immediately with no run-on, whereby small dots, shots or beads can be dispensed accurately.
US-A-3581940 discloses a dispenser container for the separate storage and proportion mixed dispensing of two interacting fluid components according to the pre-characterizing portion of claim 1. The specification discloses a tubular container of flexible material having central wall means providing two collapsible longitudinally extending compartments. The container is constructed so as to produce substantially equal internal pressures in both compartments whenever it is grasped by a hand. Separate parts are provided for each compartment at the outlet end of the container and outlet check valves control the outflow through these ports. The check valves are of the ball-and-spring non-return valve type.
It will be appreciated that if the dispenser of US-A-3581940 is used with two different fluid compositions which have different properties, i.e. with one material being more compressible than the other, the opening and closing of the non-return valves will depend upon the pressure within each respective compartment, and thus the non-return valves will open and close out of phase with each other. Thus, even this item of prior art possesses the disadvantages described above.
With the above discussion in mind, it is an object of the present invention to provide an apparatus capable of dispensing at least two different fluid compositions having different degrees of compressibility in desired proportions and, optionally of mixing the compositions being dispensed.
Accordingly, the invention provides apparatus for dispensing of at least two different fluid compositions, said apparatus comprising: a cartridge having therein plural separate chambers for containing separate fluid compositions to be dispensed; a neck portion provided at a discharging first end of said cartridge; plural separate passageways extending through said neck portion, each said passageway opening into a separate respective said chamber, the arrangement being such that the simultaneous application of pressure to the fluid compositions in each said separate chamber causes, in cooperation with a back pressure from the restriction of said passageways, compression of the fluid compositions, and thus causes the fluid compositions to be extruded in a predetermined ratio through the respective said passageways; and means for controlling the flow of the fluid compositions through the respective said passageways, for preventing run-on of the fluid compositions through said respective passageways due to decompression of the fluid compositions upon removal of the pressure, and thereby for preventing dispensing of the fluid compositions through said respective passageways in a ratio other than said predetermined ratio, said controlling means comprising a valve member having therethrough plural passage portions, said valve member being mounted within said neck portion for movement with respect thereto between an open first position, whereat said passage portions are aligned with respective said passageways, thereby permitting extrusion of the fluid compositions through said passageways in said predetermined ratio, and a closed second position, whereat said passage portions are out of alignment with said respective passageways and said passageway are blocked by said valve member, thereby preventing any flow of the fluid compositions through said passageways.
This arrangement enables the prevention of run-on of any of the fluid compositions. Thus, movement of the valve member to the closed position thereof closes the passageways and thereby prevents any run-on whatsoever of any of the fluid compositions. Such closing of the passageways also controls the flow of the fluid compositions through the passageways, and additionally such closing of the passageways prevents uneven run-on of the plural fluid compositions, thereby preventing the occurrence of the above discussed off-ratio dispensed portions.
The apparatus has been found to be particularly suitable for dispensing plural fluid compositions having different degrees of compressibility in desired proportions.
Preferably the chambers have respective volumes selected to achieve extrusion of the respective fluid compositions at the desired predetermined ratio.
The neck portion preferably extends forwardly from the first end of the cartridge.
The apparatus may include mixing and dispensing means connected to the neck portion for receiving the plural fluid compositions extruded through the respective passageways, for mixing the plural fluid compositions to form a mixed composition, and for dispensing such mixed composition. In an advantageous arrangement of the present invention, the mixing and dispensing means may comprise a nozzle structure adapted for removable connection to an outer surface of the neck portion. The nozzle structure may include a nozzle member positioned at the discharge end of the neck portion and having therein a fixed mixing element capable of achieving mixing solely due to the pressure of extrusion of the fluid compositions, and a flanged coupling fitting over a portion of the nozzle member and threaded onto the outer surface of the neck portion, thereby holding the nozzle in position against the neck portion.
Preferably, the valve member is mounted in the neck portion for rotation between said open and closed positions. In an advantageous arrangement, the neck portion includes an enlarged block portion having therethrough an opening transversely interrupting and intersecting the plural passageways and said valve member includes a stem portion rotatably fitted within such opening, said passage portions comprising parallel holes extending through the stem portion in directions transverse to the rotational axis of the stem portion. The stem portion may have a cylindrical configuration. The valve member may further include a head portion integral with a first end of the stem portion at a location exterior of the block portion and having an irregular configuration enabling engagement thereof by a tool for rotation of the valve member. There may be provided means on the head portion for indicating the - orientation of the holes and thereby for providing a visual indication of whether the valve member 'is in the open or closed positions. A second end of the stem portion may have therein a groove at a location exterior of the block portion, and a lock device may fit within the groove for retaining the valve member within the block portion.
In a particularly preferred arrangement of the present invention, the plural separate chambers of the cartridge include a cylindrical first chamber and an annular second chamber coaxially surrounding the first chamber. The first and second chambers may respectively contain first and second fluid compositions which cure when mixed together.
In order that the invention may be more readily understood, and so that further aspects of the invention may be appreciated, an embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIGURE 1 is a partially exploded longitudinal cross-sectional view of a preferred embodiment of the apparatus of the present invention;
FIGURE 2 is a partial cross-sectional view of a portion of Figure 1, showing a valve member rotated 90 degrees with respect to the position thereof shown in Figure 1; and
FIGURE 3 is an end view of the apparatus, as viewed from the left end of Figure 1, illustrated with the mixing nozzle removed.

With reference now to the accompanying drawings, a preferred embodiment of the present invention will be described. The drawings illustrate an apparatus for proportioning, a mixing and dispensing two fluid compositions or components which cure when mixed together. Such two components may have different degrees of compressibility, due to the factors discussed above. The two fluid compositions may be components of a known adhesive, sealant or mastic system, as well as other systems the components of which cure when mixed together, as will be apparent to those skilled in the art. It is to be understood however that the present invention is not intended to be limited to a two component system, but is employable for a system capable of proportioning, mixing and dispensing of more than two components. Furthermore, it is intended that the present invention be directed to an apparatus for proportioning and dispensing plural fluid compositions, as well as to an apparatus for proportioning, mixing and dispensing plural fluid compositions.
The illustrated apparatus includes a cartridge, generally indicated at 2, having therein a first, for example cylindrical, chamber 4 surrounded by a second, for example annular chamber 6. The two chambers are entirely separate from each other and are adapted to contain respective fluid compositions or components which cure when mixed together and which have different degrees of compressibility. The volume of each chamber may be selected to achieve extrusion of the compositions at a desired ratio.
A neck portion 8 extends forwardly from a discharge end of the cartridge 2. The neck portion 8 has first and second passageways 10, 12 extending therethrough each opening into a respective one of the chambers 4 and 6. The ends of the chambers 4 and 6 opposite to the neck portions 8 are sealed and closed by respective closure members 14 and 16. Suitable means (not shown) may be provided to apply pressure to the closure members 14 and 16 whereby the compositions may be discharged from the cartridge 2.
Upon simultaneous application of pressure to the closure members 14, 16, and thereby to the fluid compositions in chambers 4, 6 respectively, the fluid compositions are urged toward the discharge end of the cartridge. Due to a back pressure created by the restriction caused by the passageways 10, 12, as well as by a mixing device 36, to be discussed in more detail below, which may be attached to the neck portion 8, the two fluid compositions tend to be compressed. However, as the two compositions have different degrees of compressibility, the less compressible material will begin to discharge first through its respective passageway when the passageways 10,12 are open. Initially, as the less compressible material begins to flow the more compressible fluid composition will still be undergoing compression and discharge of the second more compressible composition through its respective passageway will be retarded until after sufficient compression thereof for causing discharge from the chamber is achieved. After this initial off-ratio situation, and upon continued application of extrusion pressure, the two fluid compositions will be extruded in a desired predetermined ratio through the respective passageways 10, 12. However, upon removal of the extrusion pressure, the two fluid components will tend to decompress, and in prior art apparatus this results in run-on as discussed above. Furthermore, due to the different degrees of compressibility of the two fluid compositions, the extent of such run-on will be different. In previously available apparatus the problem results in off-ratio portions as discussed above.
Apparatus of the present invention, is provided with a structure for controlling the flow of the two fluid compositions through passageways 10, 12 to prevent run-on of the two fluid compositions through the respective passageways 10, 12 due to the different decompression rates of the fluid compositions upon removal of the extrusion pressure, and thereby to prevent dispensing of the two fluid compositions through the respective passageways 10, 12 in ratios other than the desired predetermined ratio. As illustrated such structure may include, a valve member, generally indicated at 18. The valve member 18 includes a stem portion 20, preferably cylindrical in shape, and is rotatably mounted within the neck portion 8. First and second passage portions, in the form of holes 22, 24, respectively, extend through the stem portion 20 which is sealingly rotatable within an opening 26 extending through an enlarged block portion 28 of neck portion 8. The block portion 28 has an opening therethrough that transversely interrupts the passageway 10, 12 and receives the stem portion 20 of the valve member 8. More specifically, the valve member 18 is rotatable with respect to the block portion 28 between an open position, illustrated in Figures 1 and 3, whereat the passage portions 22, 24 are aligned with respective passageways 10, 12 thereby permitting extrusion of the fluid compositions through the passageways in the desired predetermined ratio, and a closed position, illustrated in Figure 2, whereat the passage portions 22, 24 are out of alignment with the respective passageways 10, 12 and the passageways 10, 12 are blocked by the valve member, thereby preventing any flow of the fluid compositions through the passageways.
The valve member has, at a first end thereof, a head portion 30 that is integral with stem portion 20, is located exterior to the block portion 28 and has an irregular configuration, such as a hexagonal configuration, enabling engagement thereof by a suitable tool for rotation of the valve member. An alignment device, such as a straight line indicator 32, may be provided on the head portion 30 to indicate the orientation of holes 22, 24 and thereby to provide a visual indication of the position of the valve member. A second end of the stem portion 20 may have therein a groove at a location exterior of the block portion 28, to receive a suitable element, such as a lock ring 34, that may be fitted within such a groove for retaining the valve member 18 within block portion 28.
It will be apparent that by rotation of the valve member 18 from the position shown in Figure 1 to the position shown in Figure 2, all passage of the fluid compositions through the passageways 10, 12 will be blocked. This prevents any unequal run-on of the two compositions, and resultant off-ratio patches, as discussed above.
Optionally a mixing and dispensing structure, shown generally at 36 in Figure 1, may be connected to neck portion 8 for receiving the plural fluid compositions extruded through the respective passageways 10, 12 for mixing such plural fluid compositions to form a mixed composition at the desired predetermined ratio, and for dispensing such mixed composition. The mixing and dispensing structure 36 includes a nozzle removably connected to the outer surface of the neck portion 8. Specifically, a nozzle member 38 is positioned at a discharge end of neck portion 8 and fixed mixing elements 40, capable of achieving mixing solely due to the pressure of extrusion of the fluid compositions, are positioned within the nozzle. A flanged coupling 42 fits over a portion of nozzle member 38 and is threaded onto the outer surface of neck portion 8, to hold the nozzle member 38 in position against the neck portion. The mixing and dispensing structure 36 is intended to be an in-line motionless mixing device. It will be apparent from the structure illustrated in Figure 1, that the two fluid compositions do not come in contact until they are discharged into the nozzle member 38. Thus, the fluid compositions do not mix and cure in an area that could cause locking of the structure 36 onto the neck portion 8, and the structure 36 may readily be removed when desired. The two fluid compositions never mix within the internal structure of the cartridge 2, the neck portion 8 or the valve member 18.
Although the present invention has been described and illustrated with regard to a preferred embodiment thereof, it is to be understood that many structural modifications may be made to the specifically described and illustrated arrangement without departing from the scope of the present invention as defined in the appended claims. For example it is contemplated that the cartridge structure, the closure member structure, and the mixing and dispensing nozzle structure may be as disclosed in US-A-4366919 published January 4, 1983 and in GB-B-2019952. Furthermore, it is intended that the apparatus of the present invention be employable with any suitable arrangment for applying the extruding pressure to the multiple fluid compositions. Such extruding pressure applying devices may be, for example, as disclosed in such US-A-4366919 and GB-B-2019952. The disclosure of US-A-4366919 and GB-B-2019952 is hereby incorporated by reference.
The features disclosed in the foregoing description, in the following claims and/or in the accompanying drawings may, both separately and in any combination thereof, be material for realising the invention in diverse forms thereof.

Claims

1. Apparatus for dispensing of at least two different fluid compositions, said apparatus comprising: a cartridge having therein plural separate chambers (4, 6) for containing separate fluid compositions to be dispensed; a neck portion (8) provided at a discharging first end of said cartridge; plural separate passageways (10, 12) extending through said neck portion, each said passageway opening into a separate respective said chamber, the arrangement being such that the simultaneous application of pressure to the fluid compositions each in said separate chamber causes, in cooperation with a back pressure from the restriction of said passageways, compression of the fluid compositions, and thus causes the fluid compositions to be extruded in a predetermined ratio through the respective said passageways; and means (18) for controlling the flow of the fluid compositions through the respective said passageways, characterised in that said means (18) are adapted to prevent run-on of the fluid compositions through said respective passageways due to decompression of the fluid compositions upon removal of the pressure, and thereby for preventing dispensing of the fluid compositions through said respective passageways in a ratio other than said predetermined ratio, said controlling means comprising a valve member (18) having therethrough plural passage portions (22, 24), said valve member being mounted within said neck portion (8) for movement with respect thereto between an open first position, whereat said passage portions are aligned with respective said passageways, thereby permitting extrusion of the fluid compositions through said passageways in said predetermined ratio, and a closed second position, whereat said passage portions are out of alignment with said respective passageways and said passageways are blocked by said valve member, thereby preventing any flow of the fluid compositions through said passageways.

2. Apparatus according to claim 1, wherein said chambers (4, 6) have respective volumes selected to achieve extrusion at said predetermined ratio.

3. Apparatus according to claim 1 or claim 2, wherein said neck portion (8) extends forwardly from said first end of said cartridge (37).

4. Apparatus according to claim 1, claim 2 or claim 3, further comprising mixing and dispensing means (36) connected to said neck portion for receiving the plural fluid compositions extruded through the respective said passageways, for mixing the plural fluid compositions to form a mixed composition, and for dispensing said mixed composition.

5. Apparatus according to claim 4, wherein said mixing and dispensing means (36) comprise a nozzle structure adapted for removable connection to an outer surface of said neck portion.

6. Apparatus according to claim 5, wherein said nozzle structure comprises a nozzle member (36) positioned at the discharge end of said neck portion and having therein a fixed mixing element (40) capable of achieving said mixing solely due to said pressure of extrusion of the fluid compositions, and a flanged coupling (42) fitting over a portion of said nozzle member and threaded onto said outer surface of said neck portion, thereby holding said nozzle member in position against said neck portion.

7. Apparatus according to any one of claims 1 to 7, wherein said valve member (18) is mounted in said neck portion (8) for rotation between said open and closed positions.

8. Apparatus according to claim 7, wherein said neck portion (8) includes an enlarged block portion (28) having therethrough an opening transversely interrupting said plural passageways (10, 12), and said valve member (18) includes a stem portion (20) rotatably fitted within said opening, said passage portions comprising parallel holes extending through said stem portion in directions transverse to the rotational axis of said stem portion.

9. Apparatus according to claim 8, wherein said stem portion (20) has a cylindrical configuration.

10. Apparatus according to claim 8 or claim 9, wherein said valve member (8) further includes a head portion (32) integral with a first end of said stem portion at a location exterior of said block portion and having a configuration enabling engagement thereof by a tool for rotation of said valve member.

11. Apparatus according to claim 10, further comprising means (32) on said head portion for indicating the orientation of said holes and thereby for providing a visual indication of whether said valve member is in said open or said closed position.

12. Apparatus according to any one of claims 8 to 11, wherein a second end of said stem portion has therein a groove at a location exterior of said block portion, and further comprising lock means (34) fitting within said groove for retaining said valve member within said block portion.

13. Apparatus according to any one of claims 1 to 12, wherein said plural separate chambers (4, 6) comprise a cylindrical first chamber and an annular second chamber coaxially surrounding said first chamber.

14. Apparatus according to any one of claims 1 to 13, wherein first and second chambers (4, 6) respectively contain first and second fluid composition which cure when mixed together.