This invention relates to improvements in dispensers for foams and the like. The term “and the like” encompasses liquors which can be delivered from aerosols or other dispensers, which expand, such as shaving gels, shaving foams, shower gels and creams, soaps, toothpaste, food products, cleaning products, and various industrial products.
Dispenser caps for such liquors tend to use very narrow channels or passages, because after use the channels, for example between the dispensing mechanism and an outlet orifice, are full of the product. This product continues to expand and push at least a beadlet of product from the orifice and sometimes leads to an unsightly and wasteful dribble of product from the orifice.
A partially successful solution for some products has been to use a channel or passage leading to the outlet orifice which has at least one resilient wall so that the channel constricts after use. An example of an outlet device in which the outlet channel has at least one resilient wall is described in the applicant's co-pending International patent application WO 2004/018111 and is shown in
For a full description of the construction and operation of the known spray-through cap nozzle, the reader should refer to WO 2004/018111. However a brief description of the known spray-through nozzle follows with reference to
To actuate the dispenser to cause the contents of the canister to be dispensed through the nozzle arrangement, the upper part 613 is pressed downwards in the direction of arrow A by an operator. This causes the lower part 612 of the nozzle arrangement to engage and open the valve.
As can be seen from
The provision of an outlet passage having at least one resiliently biased wall is successful for many products but in the case of some foams and gels, these expand considerably and tend to cling initially to surfaces. Even with the best fitted caps, gaps arise, and some of the gel causes a wetted area between the internal surfaces which takes time to clear, and there are dead spaces within the valve itself and these also allow occurrence of post-foaming of the product. This may result in a small beadlet or “pea” of product issuing from the outlet orifice sometime after use of the dispenser.
It is an object of the invention to provide a dispenser for liquors, pastes or foams and the like fluid materials wherein means are provided to reduce or substantially eliminate the emergence of post-foamed gel or other material from a dispensing orifice after completion of a dispensing operation.
According to the invention, there is provided a dispenser for liquors, pastes or foams and the like fluid materials as defined in claim 1.
Additional features of the invention are to be found in the claims dependent on claim 1.
The invention may be embodied in an aerosol dispenser, a pump-action dispenser, or any other suitable dispenser.
Several embodiments of dispensers in accordance with the invention will now be described, by way of example only, with reference to the remaining drawings, wherein:—
Like reference numerals are used to denote like parts in the following description of the various embodiments of the invention.
The top or discharge end of the container 10 is provided with a central discharge valve 12 in a boss or protrusion 9, and is also provided with a circumferential groove 13 which receives a rib 14 around the bottom of a skirt 15 of the dispenser cap 11. The container may be an aerosol canister. The cap 11 has a displaceable part 16 which can be pressed downwards towards the end of the container 10 to operate a dispensing mechanism. A space 17 is shown between the cap 11 and container 10 which merely allows depression of the cap part 16. Depression of the part 16 may operate the valve 12, causing it to discharge fluid from the container 10, such as shaving gel to be expelled via a passageway 18 in the cap 10 which is opened up by operation of the part 16 to leave via an outlet orifice 19. One wall of the passageway 18 e.g. the top wall may be resiliently flexible and may be constructed in a manner similar to the outlet passageway of the known spray-through cap 610 described above in relation to
In accordance with the present invention, a post-expansion chamber 20 is provided within the space 17 and this is defined by member 21 of e.g. flexible plastics material, which comprises a cylindrical skirt 22 adapted to fit snugly around the protrusion 9 containing the valve 12, a boss 23 at the other end of the member to fit in a socket in the cap 11 and having an axial bore 24 which communicates between the post-expansion chamber 20 and the passageway 18. The main part of the member 21 is comprised by a diaphragm member substantially in the form of a single-pleated bellows which acts to expand or contract the volume of the chamber 20 as the displaceable part 16 of the cap is pressed down towards the container top, or released and allowed to return to its un-depressed position.
When the part 16 is pressed, the space 17 and the post-expansion chamber 20 are reduced in volume, and any existing charge of gel therein is propelled into and along the passageway 18 to issue from the orifice 19. When the pressure on part 16 is released, and it is allowed to return to its undepressed position (being preferably resiliently biased into such un-depressed position), the space 17 and 20 are allowed to expand once more, and the valve 12 is closed stopping flow from the container 10. The post-expansion chamber 20 draws back any final bead of gel from the previous charge from passage 18 and allows it to expand in the chamber 20 as it normally would on leaving the outlet orifice 19, and the appearance of a beadlet of foam at the outlet between uses is prevented.
A second embodiment is illustrated in
In either of the first two embodiments, once the part 16 is again pressed, the post-expansion chamber 20 immediately collapses and the material therein is expelled via the normal exit route, and then the valve 12 is activated leaving the next charge of fluid to enter the passageway 18. As the new fluid meets the old fluid, it mixes and redisolves any of the latter which has dried out. The expanded product is reduced to a fraction of its expanded size when the chamber is collapsed. The diaphragms 21, 32 are not usually resilient but may be if required.
The caps 11 may be made using a bi-injection moulding process, and the chambers may be formed integrally therewith.
In a variant, the post-expansion chamber may be arranged never to be emptied, but continually recompressed so as to contain the dried out excess instead, leaving a collection of dried out waste product.
The product tends to take the easiest route so it will tend to find the post-expansion chamber rather than the outside especially if the chamber is near to the input as that is where the build up of product in the passage is greatest. Some of the product may be allowed to deliberately enter the collapsed chamber to wash out any dried up product on the way out.
The embodiments described above can be applied to dispensers having an outlet passage defined wholly by means of a rigid wall or walls or dispensers in which the outlet passage is defined by means of at least one flexible, resiliently deformable wall. With this latter type of outlet passage, there is normally a bias in the flexible part that is arranged to urge the product out through the outlet orifice. However, when a post-expansion chamber in accordance with the first two embodiments is provided, this bias could be reserved so as to urge the product into the post-expansion chamber if required.
The post-expansion chamber may be made with an extra part or adaptor that is located between the valve and the valve cup of the cap. This could be made from the same flexible material as is used to form a flexible wall of the outlet passage, and this could be located inside the valve cup on the cap and on the valve or preferably on a central metal cup or plinth that surrounds the valve. This would entail no additional cost as it would be manufactured as a one piece bi-injection moulding. If both ends are sealed then this effectively creates a pump like a bellows pump and this is preferable in many cases. This also tends to draw the product back into the chamber by suction and reduces any residual post foaming outside of the cap. The flexible outlet passage acts like a seal and can be provided with a plug arranged to enter the top of the vertical passage leading to the post-expansion chamber, so as to keep the product in the chamber wet which is easier for ejection.
Any means of creating and reducing a chamber may be used and therefore a plunger inside a tube could be used with the plunger reducing the chamber as the cap is pressed. So, for example, the plunger could be on the valve (or part of the valve) and this could push into the cap valve cup which could be extended.
The collapsible post-expansion chamber could be of any shape, including a bellows or collapsible plunger or very flexible plastic. The entire cap could define the chamber and allow the product to build up inside this chamber. The cap may then preferably be sealed by putting a flexible moulding around the actuator on the cap that is pressed by a user's finger.
The chamber could be inside the valve instead of in the cap and would work in the same way. The valve itself could alternatively collapse the channel in the same way that the cap channel is collapsed to further reduce the problem.
If the collapsible post-expansion chamber is located where a user's finger presses on the cap then it could look like a small flattened dome. The finger would depress this dome prior to moving the cap and valve. As soon as the finger is released, the dome would be free to rise, either sucking in the product like a pump or allowing it to seep in. An example of this arrangement is illustrated in
As shown in
When the dispenser is actuated, as shown in
When the user stops pressing on the cap 11, the flexible dome member 16E will be restored to its resiliently biased position, as shown in
The dispenser cap 11 can be manufactured using a bi-injection process with the upper cover portion 16D being over moulded from a flexible plastics material on to the lower portion 16A which is moulded from a relatively rigid plastics material.
In an alternative embodiment, not shown, the post-expansion chamber 20 may be provided underneath the displaceable portion 16. Thus the flexible dome member 16E could be formed underneath the displaceable portion 16 so that it is depressed by contact with the container 10 or with some other abutment member when the displaceable portion is depressed to operate the dispenser.
In certain embodiments, part of the outlet passage 18 could become the post-expansion chamber. For example, the outlet passage could be defined in part by means of a resiliently flexible wall. The arrangement could be such that the flexible wall defines an open passage when in a rest position and pressing down on the cap would cause the passage to collapse and releasing the cap would cause it to reform. If a flexible top is used in this way, there would initially be a passage or channel and pressing the trigger would bring the flexible top into contact with a rigid base. When collapsed the flexible top would work with the pressure of the product entering the dispenser cap forcing the flexible top to rise, creating the channel and then collapsing the channel after use. Then when the trigger is released, the channel would become exposed again. If a rigid top is used then the channel would partially close so that there is still enough room for the product to pass through. Afterwards, the channel expands leaving enough room inside it for the post foaming to take place therein.
The cap 11 has an outlet passage 18 that is at least partly defined by a resiliently deformable wall in a similar manner as the known spray-trough cap described above with reference to
As shown in
In accordance with the invention, a post-expansion chamber is formed in the outlet groove by clamping an end portion of the resiliently deformable wall 43 close to the outlet orifice against the groove 42 when the dispenser is not in use. This seals the end of the outlet passage 18 so that any product remaining in the outlet passage is retained between the wall 43 and the groove 42. Any expansion of the product in the groove can be accommodated by the wall 43 lifting away from the groove 42 in the centre to form a post-expansion chamber.
In the present embodiment, the end portion of the wall 43 is clamped to the groove by means of an abutment or clamp member formed in the over cap 40 that is adapted to be fitted over the cap 11 when the dispenser is not in use.
The abutment or clamp member is provided by means of a recessed portion 54 at the front of the over cap and which is positioned so as to align with the wall 43 when the over cap is fitted to the cap 11. The cap 11 and over cap 40 may have means to ensure that the over cap 40 can only be mounted on the cap 11 in the correct position to ensure that the recessed portion 54 aligns with the wall 43
The recessed portion 54 of the over cap has a base 55 which is arranged to contact an end portion of the wall 43 and to firmly hold the end portion of the wall in contact with the groove 42 when the over cap 40 is fitted to the cap 11. The base 55 may be curved to match the curve of the groove 42 to ensure that the wall 43 contacts the groove 42 over its entire width and so forms an effective seal. As described above in relation to the known spray-through cap, a horseshoe shaped seal 619 surrounds the groove 42 and the flexible wall 43. To prevent any product trapped in the outlet passage from escaping past the seal, a further abutment means in the form of a rib 56 depends from the top of the over cap to engage the resiliently deformable wall 43 close to the inlet end 57 of the outlet passage. The rib 56 is shaped to contact the flexible wall 43 and hold it in contact with the rigid surface of the groove 42. Because the product is retained in the outlet passage 18, it is sealed from the air and will tend to remain in a wet condition.
When the dispenser is to be used, the over cap is removed and the wall 43 is free to be displaced away from the groove 42 by the pressure of the contents of the container entering the outlet passage in the usual way.
A modification of the previous embodiment is illustrated in
The cap 11 and over cap 40 of the modified embodiment are also provided with a locking means to prevent accidental actuation of the dispenser when the over cap is fitted. A resilient tab 59 is formed in the cap 11 adjacent to the free end of the displaceable part 16. The tab 59 is generally U shaped in cross section with a first wall 60 of the U being connected to the skirt portion 51 of the cap and the second wall 61 freely extending upwardly towards a lower surface of the displaceable part 16.
In its relaxed state, the second wall 61 of the tab is positioned so that it is aligned to the right, as shown in
A problem with the previous two embodiments described above is that a user may discard the over cap 40 rather than replacing it after every use.
A catch member 66 is formed integrally with the cap 11 and is pivotally attached to the skirt 15 of the cap by means of a live hinge 67. The catch member can be moved through an arc, indicated by arrow B in
The catch member has an abutment portion 70 that is adapted to engage an outer end portion of the flexible wall 43 defining the outlet passageway 18 and to hold the wall 43 in contact with the opposing surface of the groove 42, when the catch member is in the locked position. The abutment portion is shaped so that it holds the end portion flexible wall 43 in contact with the groove over its full width so as to ensure that the outlet passage is fully sealed. Hence, with the catch member 66n the locked position 68, a post-expansion chamber is formed in the outlet passage 18 between the remainder of the flexible wall 43 and the groove 43.
To use the dispenser cap, the catch member 66 is simply pivoted by a user to the unlocked position 69 and the dispenser cap 11 can be used in the conventional way. The catch member 66 can be shaped to make it easier to use by, for example, having a shaped formation 71 at the front that a user can easily engage to move the cap between the locked and unlocked positions. Furthermore, detent means may be provided to ensure the catch member is positively held in the locked position 68. Such detent means could take the form of abutment means on the catch member that co-operate with corresponding abutment means on the main body of the cap.
The catch member 66 also incorporates locking means 72 to prevent the dispenser cap being actuated when the catch member is in the locked position 68. As shown in
It will be appreciated that whilst the present embodiment uses an integrally formed catch member 66, the catch member could be a separate component mounted to the cap 11. It will also be appreciated that the catch member could take many forms. For example, that catch member could be arranged to pivot in a different manner to that shown in
The central boss 50 includes a first recessed portion 80 into which the valve stem 12 is received. A passage 82 connects the interior of the recessed portion 80 of the boss 50 with the outlet passage 18 so that the product released from the valve stem 12 can enter the outlet passage. The resiliently flexible wall 43 that defines part of the outlet passage 18 has a small circular skirt 84 which locates within the passage 82 to form a flexible bell defining a post expansion chamber 20.
When the dispenser is actuated, the product is dispensed under pressure from the valve stem 12 and pushes on the underside of the flexible bell defined by the skirt 84 and the flexible wall 43. The pressure of the product lifts the flexible wall 43 and the skirt 84 upwardly in the passage 82 until an opening 86 between the passage 82 and the skirt 84 is formed to allow the product to enter the outlet passage 18. In the present embodiment, the opening 86 is created by means of a projection 88 on the upper, forward edge of the wall that defines the passage 82. As shown in
Once actuation of the dispenser is stopped, the resilience of the flexible wall 43 will cause it to try to revert to the position shown in
A small amount of post foaming may also occur in the outlet passage 18 itself, particularly around the inlet end 57 in the region of the skirt 84. When the flexible wall 43 and skirt 84 are moved upwardly as shown in
To help the skirt 84 seal in the passage 82, the passage is preferably arranged to taper inwardly from a lower, inlet end towards an upper, outlet end. However, the passage 82 could have generally parallel walls with an outwardly flaring region at the lower, inlet end against which the skirt 84 can seal. As a further alternative, rather than a flared region, the passage could have a semi-circular indent at the lower end which acts effectively like an O-ring around the bottom of the skirt.
Rather than a flexible skirt 84, other suitable seal means can be arranged to project into the passage 82 provided they can function to seal the passage to prevent post foaming product from entering the outlet passage 18 but are able to be moved or deformed sufficiently to allow the product to be dispensed when required. The seal member could be solid rather than hollow, for example.
Furthermore, rather than relying on the pressure of the dispensed product to raise the skirt 84 or other seal member, it could be arranged that the valve stem 12 engages with the skirt 84 or seal member to mechanically move it upwardly in the passage 82 when the dispenser is activated. When the dispenser is released, the valve stem will move away from the skirt 84 or other seal member to allow it to return to its rest position.
Although the present embodiment has been described with reference to the type of dispenser cap shown in
Dispensers in accordance with the invention may be adapted for use with a range of fluids, including gels, foams and mousses, toothpaste, soaps, food products, e.g. whipped emulsion products, and various industrial products. Whilst most of the embodiments described are aerosol type dispensers, the invention can be adapted for use with a variety of dispensers including manually actuated pumps and trigger dispensers, and squeezy tubes or bottles and any other pressurised source. Certain
Whilst the embodiments described have all included an actuator means in the form of a dispenser cap that fits on the end of a canister or other reservoir, the invention can be modified for use in dispenser devices, such as manual pump and trigger dispensers, which may not have a dispenser cap as such but which may incorporate an alternative actuator means formed integrally with or otherwise mounted to a container or reservoir.
The invention can also be modified for use with dispensers in which two or more products are mixed in a chamber prior to being dispensed. This could include dual liquor/paste dispensers of any type. Thus a post-expansion chamber could be provided downstream of the mixing chamber. The post-expansion chamber may be arranged to collapse when the dispenser is actuated but reform afterwards to accommodate any foam or other product generated as a result of residual mixing in the mixing chamber. Indeed the mixing chamber could be adapted for use as the post-expansion chamber itself. Thus a mixing chamber may be arranged such that its volume is reduced during use when it acts as a mixing chamber but to increase when the dispenser is no longer being actuated in order to accommodate any residual product. Alternatively, the mixing chamber may be positioned immediately adjacent the outlet orifice and can be adapted to collapse after use of the dispenser to force any remaining product out of the outlet. If this takes place very quickly at the end of the dispensing phase, the expelled product would become part of the main product stream rather than a post foaming or dribble.
Whereas the invention has been described in relation to what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not limited to the disclosed arrangements but rather is intended to cover various modifications and equivalent constructions included within the spirit and scope of the invention. For example, whilst in the embodiments disclosed the outlet is aligned generally horizontally when the dispenser is held upright, the invention can be equally applied to dispensers having a vertical outlet or an outlet arranged at any other orientation.
Where the terms “comprise”, “comprises”, “comprised” or “comprising” are used in this specification, they are to be interpreted as specifying the presence of the stated features, integers, steps or components referred to, but not to preclude the presence or addition of one or more other feature, integer, step, component or group thereof.
Number | Date | Country | Kind |
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0417249.0 | Aug 2004 | GB | national |
0424311.9 | Nov 2004 | GB | national |
0504152.0 | Mar 2005 | GB | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/GB2005/003031 | 8/2/2005 | WO | 00 | 9/15/2008 |