WO1998028207A1

WO1998028207A1 - Actuator cap for an aerosol dispenser

Info

Publication number: WO1998028207A1
Application number: PCT/GB1996/003208
Authority: WO
Inventors: Guy Richard Thompson; Gerald Leslie Hart
Original assignee: S.C. Johnson & Son, Inc.
Priority date: 1996-12-23
Filing date: 1996-12-23
Publication date: 1998-07-02
Also published as: AU715565B2; AU1201897A; CA2272886A1

Abstract

An aerosol canister (1) is equiped with a spray cap (10) made by assembling two separate parts. The spray cap (10) has a one-piece outer member (10a) for fitting on the canister (1) including an integral inner member (18) adapted to receive and retain a separate button actuator (23) with a nozzle (24). The button actuator (23) has an engaging means (25, 26) for aligning the nozzle (24), e.g. a combination of groove (25) and rib (26), with a window (19) in the inner member (18), and for engaging with the inner member (18) so as to allow the button actuator (23) to be inserted and retained in the inner member (18), e.g. by a barb (27). The spray cap (10) may be applied to a canister (1) in a fixed relation to a dip tube (5) within the canister (1) by fitting the button actuator (23) in the inner member (18) of the outer member (10a) before applying the spray cap (10) to the canister (1).

Description

ACTUATOR CAP FOR AN AEROSOL DISPENSER

Technical Field The present invention relates to aerosol canisters and to caps suitable for mounting on such canisters.

Background Art Hand-held aerosol dispensers comprising a cylindrical canister filled with material to be dispensed through a nozzle by a propellant gas are known. Frequently the product is dispensed as a finely divided spray, but may sometimes be dispensed as a foam or a relatively thin jet. A standard aerosol canister has a valve mounted at its upper end, on which a delivery mechanism is mounted. The valve often has a short projecting tube, the valve stem, on which the delivery mechanism is mounted, although sometimes the delivery mechanism may project into the canister through an aperture to make contact with the valve. A dip tube usually extends downwardly from the valve into the canister, up which product is forced by propellant when the valve is opened. Small button actuators with nozzles are known for use with aerosol dispensers. Some button actuators release product as a result of downward pressure on the actuator, while others release product in response to sideways pressure on the actuator (depending on the type of valve used). The button actuators can be installed by being pushed down on to the valve. A separate cap which fits on to the cylindrical canister protects the button actuator from accidental operation. However the use of a separate protective cap, which has to be removed before the button actuator can be used, is inconvenient.

To overcome the disadvantages of a separate cap, various types of protective cap have been proposed which can be left in place on the canister when the aerosol dispenser is used.

US 3 058 626 discloses a cap whose diameter is substantially the same as that of the canister on which it is mounted and which has a depressed valley running across the top of the cap, and a separate actuator button mounted on the valve underneath the outer cap. The valley portion of the cap mentioned above may be depressed to depress the underlying actuator button. Spray passes from the nozzle in the actuator button through an aperture in the protective cover which is kept in alignment with the nozzle by a rib in the cover which slides within a groove in the actuator button.

There is no means of holding the actuator button on the cover so that they can be handled as a unit, even though produced separately.

Where dip tubes are used, they are generally made sufficiently long to reach the lowest part of the canister. Where the canister has a domed base and the dip tube is flexible, the end of the dip tube will be inclined or bent away from the centre of the canister.

Substances such as liquefied petroleum gases which are maintained as liquids under pressure within the canister are frequently used as propellants. However, compressed gas (air) is also used as a propellant. The propellant in this case is all present as a gas initially and the gaseous pressurizing medium cannot be replenished from a reservoir of liquid. It is therefore important to ensure that gas cannot escape directly through the nozzle from the canister. Where the end of the dip tube is bent as explained above, it is important for the end to be aligned in relation to the direction in which the product is dispensed, so that when the container is tilted the end of the dip tube is covered with liquid even when the container is nearly empty. This prevents premature escape of propellant. The bent end of the dip tube has to be aligned in relation to the aerosol nozzle. If the canister is to be used in a position in which the spray is directed upwards, the end of the dip tube should be directed towards the side of the canister which is opposed to the direction of spray of the nozzle. If the canister is to be used to dispense material in a downward direction, then the bent end of the dip tube should lie on the same side of the canister as that to which the spray is directed.

One known type of aerosol dispenser has a cylindrical canister and a large spray cap whose outer wall is flush with the cylindrical body of the canister. The caps have a spray nozzle in the outer wall and an internal passage linking the nozzle to the outlet from the canister. These large caps can be rotated at the production stage so that the nozzle in the outer wall is aligned with the end of the dip tube.

Some products dispensed using compressed gas (e.g. spray starches) are relatively thick. If used with caps having long internal passages, the passages are likely to become clogged.

The known small button actuators are less likely to become clogged because of the shorter path between the dip tube and the nozzle. However, some mechanized production lines for installing caps on aerosol canisters cannot automatically align these small button actuators with the lower end of the dip tube at the production stage. There is a need for an improved nozzle system for use with aerosol dispensers which allows for a fixed orientation of the spray nozzle in relation to the canister but provides a short path from the canister to the nozzle, and which uses components which can be used separately for other types of aerosol dispensers where such fixed alignment is not required.

Disclosure of Invention According to one aspect of the present invention there is provided an aerosol dispenser comprising a) a cylindrical canister having a valve mounted centrally on said canister and communicating with a dip tube within said canister and b) a spray cap adapted to fit on the canister wherein the spray cap comprises as separate parts i) an outer cap having an outer member adapted to fit on the canister and an inner member defining an opening extending around the valve and shaped to allow spray to pass through the inner member, said outer member being so shaped as to allow spray passing through the inner member to pass out of the spray cap, and ii) an inner button actuator having a nozzle opening and adapted to fit on said valve, said button actuator having engaging means for engaging with the inner member of said outer cap so as to hold the actuator button in the inner member with the nozzle opening aligned so as to allow spray to pass through the inner member.

According to a further aspect of the present invention, there is provided a spray cap suitable for use on an aerosol canister having a valve, which cap comprises as separate parts : i) an outer cap having an outer member adapted to fit on the canister and an inner member defining an opening extending around the valve and shaped so as to allow spray to pass through the inner member, said outer member being so shaped as to allow spray passing through the inner member to pass out of the spray cap, and ii) an inner button actuator with a nozzle opening and adapted to fit on said valve, said button actuator having engaging means for engaging with the inner member of said outer cap so as to hold it in the inner member with the nozzle opening aligned so as to allow spray to pass through the inner member.

According to a further aspect of the present invention, there is provided a button actuator for mounting on an aerosol canister , said button actuator being suitable for insertion into a spray cap and comprising a body, a base by which it is mounted on an aerosol canister valve, and a top to which pressure is applied in use to operate the button nozzle and having an inlet opening at its base, a nozzle opening in the body substantially at right angles to the inlet opening, and an internal passage within the body linking the inlet opening and the nozzle opening, said button actuator further comprising an engaging means for engaging with an outer cap so as to hold the button actuator in a defined position relative to the spray cap wherein the engaging means comprises a barb on the body which permits insertion of the button actuator into the spray cap but resists removal of the button actuator from the spray cap.

According to a further aspect of the present invention,there is provided a process for mounting a spray cap on an aerosol canister in a mechanized packaging line which comprises the steps of

1) providing an aerosol canister charged with product and propellant and having at an upper end a valve with a valve stem and having a dip tube having an open end directed towards one side of the canister and with said open end in a fixed alignment with the canister, 2) providing an outer cap having an outer member adapted to fit on the canister and an inner member defining an opening extending around the valve shaped so as to allow spray to pass through from within the inner member, said outer member being so shaped as to allow spray passing through the inner member to pass out of the spray cap, 3) providing an inner button actuator with a nozzle opening adapted to fit on said valve, said button actuator having engaging means for engaging with the inner member of said outer cap so as to hold it in the inner member with the nozzle opening aligned so as to allow spray to pass out of the inner member,

4) inserting the button actuator within the sleeve of the outer cap so that it is held within the sleeve with the nozzle aligned so as to allow spray to pass through the inner member, and

5) mounting the assembled cap on the aerosol canister such that the outer cap is in a defined alignment with the end of the dip tube.

In this specification^references to top and bottom or upper and lower are to be understood as referring the orientation of a component when it is in place on a cylindrical canister which is itself in an upright position. Outer and inner are to be considered in relation to the outer cylindrical wall of such a canister.

The references to "aerosol" in this specification are not to be understood in the strict scientific sense of a very fine dispersion of liquid droplets in air, but in the sense in which this is used by those concerned with packaging to cover the dispensing of products (usually consumer products) from pressurized containers, and "spray" includes the product released from such pressurized containers.

The outer cap is generally moulded from a thermoplastics polymer. A typical aerosol canister has a raised rim running around the top of the outer cylindrical wall,and the outer member of the spray cap will normally be a push fit on this outer rim. The outer member will thus normally have a substantially circular cross section at its base. Aerosol canisters commonly have a second raised bead or flange within the outer flange,and caps can be made to fit on such flanges. However the cap is preferably of such a size to fit on the outer flange.

The outer member is shaped so as to allow spray to pass out of the cap from the window in the inner member. This may be achieved by providing a depressed portion across the top of the cap. Preferably the outer member has a fixed top portion extending over the side of the cap from which the spray emerges,and a window is provided in the outer member aligned with the inner member so as to allow spray passing through the inner member to leave through the window in the outer member. Thus the window in the outer member may be aligned with a window in the inner member.

The inner member holds the button actuator against rotation relative to the inner member and also against vertical movement with respect to the inner member. The inner member will generally be in the form of a sleeve shaped to be a close fit for the actuator button. The sleeve may allow spray to pass through it by means of a spray window. The window in the inner member preferably is longer than it is wide, and preferably has a curved lower edge. The inner member may be formed with relatively thin walls reinforced with ribs, which help to align the button actuator with the interior of the sleeve when the outer cap and button actuator are brought together.

A linking member carrying the inner member and hinged to the outer member, e.g. by a moulded hinge, may be used to hold the inner member and outer member in alignment. The linking member is conveniently shaped and sized to provide an actuation surface, greater in area than the top of the button nozzle, to which finger pressure may be applied to actuate the dispenser.

The actuator is preferably of a size corresponding to conventional small actuator buttons,and preferably has a maximum width of less than 15 mm. The body of the actuator is conveniently a moulding formed from thermoplastic polymer. The spray nozzle may conveniently be a separate component which is a push fit in an aperture in the body of the actuator, as is conventional in such actuators.

The actuator has engaging means. The engaging means allows the actuator to be inserted into the inner member of the outer cap but resists withdrawal and ensures that the actuator nozzle is in alignment with the inner member so as to permit spray to pass through it. Thus it may be aligned with a window in the inner member.

The engaging means may comprise a vertical groove in the actuator button which engages with a vertical rib in the inner member to facilitate insertion of the actuator button in the outer cap in alignment with the window in the inner member. The further function of holding the actuator button within the outer cap may be provided by a barb so disposed that it allows the actuator button to be inserted into the outer cap but resists removal of the button.

The barb is preferably located in line with the spray nozzle and vertically underneath it. It may conveniently be a raised portion which slopes outwardly from the body of the actuator in the downward direction,and has a step at its lower edge when viewed at right angles to the axis of the spray nozzle.. The lower edge of the sloping portion is preferably curved (viewed looking along the axis of the spray nozzle) when the lower edge of the window in the inner member is curved. The button actuator is preferably retained in the inner member by interaction of the barb with a spray window in the inner member.

The barb action for the structure described above is achieved by deformation of the inner member by the projecting portion of the actuator which allows the insertion of the actuator into the inner member. The actuator is retained by the step in the projecting portion interacting with the lower edge of the window once the actuator has been fully inserted.

An aerosol dispenser with a cap in accordance with the present invention may be assembled as follows. An aerosol canister charged with product and propellant,and having at an upper end a valve with a valve stem and having a dip tube having an open end directed towards one side of the canister,and with said open end in a fixed alignment with the canister,is prepared. This is fed to a mechanized packaging line.

Such packaging lines are conventional in aerosol dispenser production.

Outer caps as shown in the drawings are moulded. Button actuators as shown in the drawings are moulded and spray nozzles inserted. Button actuators are then inserted into the outer caps with the nozzles aligned with the windows in the outer cap and are retained in the outer cap by the barbs. This may be done in the packaging line. However, it may be more convenient to be carried out after moulding the parts and before supplying the combined cap to the packaging line. The combined outer cap and button is then applied in the packaging line to a canister,and the cap oriented by standard means in the packaging line so that the cap is in the correct alignment with the end of the dip tube. The present invention is particularly advantageous for aerosol dispensers which contain compressed air as the propellant. The product dispensed from the dispenser is preferably a viscous material.

Brief Description of Drawings The invention will now be described with reference to the accompanying drawings in which

Figure 1 is a diagrammatic elevation of a conventional aerosol canister with a bent dip tube,

Figure 2 is a front elevation of an outer spray cap without a button actuator in place,

Figure 3 is a plan view of the outer spray cap of Figure 1, Figure 4 is a rear elevation of the outer spray cap of Figure 1,

Figure 5 is a front elevation of part of the inner member of the outer spray cap of Figure 1 with a button nozzle in place, and Figure 6 is a side elevation of the button nozzle in place in the inner member, which is shown in section.

Best Mode of Carrying Out the Invention

Figure 1 shows a conventional canister as used with a compressed gas propellant. This comprises a cylindrical canister (1) with a domed base (2). At the top of the canister there is a valve stem (3) which is connected to a valve (4) from which a dip tube (5) extends to near the base (2) . The dip tube is inclined or bent so that it terminates near one side of the canister. The canister carries an external index mark (not shown) which indicates the side of the canister near which the dip tube terminates. As is conventional in hand-held aerosol containers, the cylindrical body is linked to a first domed upper portion by a flange or bead (6) , and the first domed portion is linked to a central portion carrying the valve by a second flange or bead (7) . The canister is filled with a liquid product to be dispensed (8) , pressurized by a gas (9) , and equipped with spray cap (10) shown in Figures 2 to 6.

Referring to Figures 2, 3 and 4, an outer cap or skirt (10a) moulded from thermoplastic material has a base (11) of circular cross section of such a size as to be a push fit on the outer flange (6) of the canister shown in Figure 1. A window (12) , whose sides converge inwardly towards the interior of the cap, is defined by sloping side walls (13, 14) and bottom wall (15) and a curved top wall (16) . A thin, curved forwardly-extending top portion (17) has a periphery corresponding to the cylindrical base (11) .

A cylindrical sleeve (18) having a window (19) is visible within the window (12) . The sleeve has a plurality of vertical ribs on its outer surface. These are not shown in the interests of clarity. The sleeve is open at its lower end, and is closed at its upper end which forms part of the same plastics moulding as a pressure pad (20) , which in turn forms part of the same plastics moulding as the outer part (10a) of the cap (10) . It is linked to the outer part of the cap by a moulded hinge (21) . This enables the pressure pad (20) to move relative to the outer part of the cap, carrying the sleeve (18) with it.

The sleeve (18) has an internal diameter which is similar to the diameter of the central valve portion (4) of the aerosol canister. The sleeve is sized so as to take a conventional small diameter button actuator.

The nature of the button actuator used in the spray cap (10) of the present invention may be seen from Figures 5 and 6. These show the lower part of the sleeve (18) . The vertical ribs mentioned above are indicated at (22). They have sloping ends which help to guide the button actuator into the sleeve. An actuator button (23) with a spray nozzle (24) has been inserted into the sleeve. The actuator button is conventional in design except for the engaging means.

One element of the engaging means comprises a groove (25 ) in the side of the button opposite the nozzle (24). This groove receives a corresponding rib (26) in the inner wall of the sleeve (18), and holds the nozzle in alignment with window (19).

The other element of the engaging means is a barb (27). The barb,as seen from the side view in Figure 6,is a projecting part of the body which slopes outwardly and downwardly to form a ramp (28) and terminates in a step (29). As can be seen from

Figure 5,the ramp (28) has a curved end which closely follows the shape of the curved edge of the window (19).

The combined spray cap of the present invention has the advantage that the button actuator can be used on aerosol dispensers which have a separate cap which is removed before use. The outer cap can be used (where orientation is not important) with conventional button actuators which are placed on the canister before the outer cap is applied. This enables the number of different components required for different products to be reduced.

Claims

Claims:

1. An aerosol dispenser comprising a) a cylindrical canister having a valve mounted centrally on said canister and communicating with a dip tube within said canister and b) a spray cap wherein the spray cap comprises as separate parts i) an outer cap having an outer member adapted to fit on the canister and an inner member defining an opening extending around the valve and shaped to allow spray to pass through the inner member, said outer member being so shaped as to allow spray passing through the inner member to pass out of the spray cap, and iϊ) an inner button actuator having a nozzle opening and adapted to fit on said valve, said button actuator having engaging means for engaging with the inner member of said outer cap so as to hold the actuator button in the inner member with the nozzle opening aligned so as to allow spray to pass through the inner member.

2. An aerosol dispenser according to claim 1 wherein the aerosol canister has an outer cylindrical wall with an outer flange around the top of the cylindrical wall and the outer member of the outer cap fits on the flange.

3. An aerosol dispenser according to either of the two preceding claims wherein the inner member is in the form of a sleeve having a spray window to allow spray to pass through the sleeve.

4. An aerosol dispenser according to claim 3 wherein the outer member of the outer cap has a fixed top portion extending over the the side of the cap from which the spray emerges, and a window is provided in the outer member aligned with the window in the inner member.

5. An aerosol dispenser according to any one of the preceding claims wherein the engaging means comprises a vertical groove in the actuator button which engages with a vertical rib in the inner member to facilitate insertion of the actuator button in the outer cap in alignment in the inner member so as to allow spray to pass through the inner member.

6. An aerosol canister according to any one of the preceding claims wherein the engaging means comprises a barb so disposed that it allows the actuator button to be inserted into the outer cap but resists removal of the button.

7. An aerosol dispenser according to claim 6 wherein the barb is located in line with the spray nozzle and vertically underneath it.

8. An aerosol dispenser according to claim 7 wherein the button actuator is retained in the inner member by the interaction of the barb with a window in the inner member.

9. An aerosol dispenser according to any one of the preceding claims wherein the canister contains compressed air as propellant.

10. An aerosol dispenser according to any one of the preceding claims wherein the canister contains a viscous product to be dispensed by the propellant.

11. A spray cap suitable for use on an aerosol canister having a valve which cap comprises as separate parts i) an outer cap having an outer member adapted to fit on the canister and an inner member defining an opening extending around the valve and shaped so as to allow spray to pass through the inner member, said outer member being so shaped as to allow spray passing through the inner member to pass out of the spray cap, and ii) an inner button actuator with a nozzle opening and adapted to fit on said valve, said button actuator having engaging means for engaging with the inner member of said outer cap so as to hold it in the inner member with the nozzle opening aligned so as to allow spray to pass through the inner member.

12. A button actuator for mounting on an aerosol canister , said button actuator being suitable for insertion into a spray cap and comprising a body, a base by which it is mounted on an aerosol canister valve, and a top to which pressure is applied in use to operate the button nozzle and having an inlet opening at its base, a nozzle opening in the body substantially at right angles to the inlet opening, and an internal passage within the body linking the inlet opening and the nozzle opening, said button actuator further comprising an engaging means for engaging with an outer cap so as to hold the button actuator in a defined position relative to the spray cap wherein the engaging means comprises a barb on the body which permits insertion of the button actuator into the spray cap but resists removal of the button actuator from the spray cap.

13. A process for mounting a spray cap on an aerosol canister in a mechanized packaging line which comprises the steps of 1) providing an aerosol canister charged with product and propellant and having at an upper end a valve with a valve stem and having a dip tube having an open end directed towards one side of the canister and with said open end in a fixed alignment with the canister,

2) providing an outer cap having an outer member adapted to fit on the canister and an inner member defining an opening extending around the valve shaped so as to allow spray to pass through the inner member, said outer member being so shaped as to allow spray passing through the inner member to pass out of the spray cap,

3) providing an inner button actuator with a nozzle opening adapted to fit on said valve, said button actuator having engaging means for engaging with the inner member of said outer cap so as to hold it in the inner member with the nozzle opening aligned so as to allow spray to pass through the inner member,