Automatic dosing and spraying valve assembly

Abstract

A non-electrically powered automatic dosing and spraying valve assembly for a container of pressurized fluid with an outlet valve is described, wherein the valve assembly comprises a housing containing at least two chambers wherein one of those chambers is a main chamber open at one end to the contents of the container and closed at one end by a movable plunger, and another of those chambers is a dose chamber closed at one end by the movable plunger and closed at the other end by a prodder seal formed between a movable prodder and a fluid outlet opening; wherein the movable plunger is biased against movement toward the dose chamber by a main spring means and a prodder spring means, the main spring means being mounted in or adjacent to the dose chamber and the prodder spring means being connected to both the movable plunger and movable prodder, the assembly further comprises a fluid leak path between the main chamber and the dose chamber; and wherein the assembly is arranged such that, in use, one movable component of the assembly is configured to move relative to another component of the assembly to temporarily expose the dose chamber to the full fluid pressure of the main chamber.

Claims

1. A non-electrically powered automatic dosing and spraying apparatus comprising a valve assembly and a container of pressurised fluid with an outlet valve, wherein the valve assembly is connected to the container to open the outlet valve to permit the fluid to flow into the valve assembly and wherein the valve assembly comprises a housing containing at least two chambers wherein one of those chambers is a main chamber open at one end to the contents of the container and closed at one end by a movable plunger, and another of those chambers is a dose chamber closed at one end by the movable plunger and closed at the other end by a prodder seal formed between a movable prodder and a fluid outlet opening; wherein the movable plunger is biased against movement toward the dose chamber by a main spring means and a prodder spring means being connected to both the moveable plunger and the movable prodder; the assembly further comprises a fluid leak path between the main chamber and the dose chamber; and wherein the assembly is arranged such that, in use, the dose chamber with gradually fill with fluid and one movable component of the assembly is configured to move relative to another component of the assembly to provide a final and rapid expansion of the dose chamber, releasing and spraying a dose of fluid whilst substantially simultaneously therewith or substantially immediately thereafter returning to the start position to repeat the cycle.

2. The apparatus according to claim 1, wherein at least one of the main chamber and/or dose chamber is provided with one or more at least partial grooves therein arranged to be located adjacent said plunger sealing means when the plunger is at or adjacent to its uppermost position remote from the fluid outlet opening.

3. The apparatus according to claim 2, wherein the at least partial groove extend circumferentially and/or vertically.

4. The apparatus according to claim 1, wherein the main spring means is provided with a spring strength that is weak enough to permit the moveable plunger to travel from a starting position to a charging position when exposed, in use, to the fluid pressure from the container, whilst also being strong enough to act with resultant fluid pressure in the dose chamber to return the moveable plunger back to the start position.

5. The apparatus according to claim 4, wherein it takes of the order of 5 to 20 minutes for the plunger and the prodder to move from the starting position through the charging position and back to the starting position.

6. The apparatus according to claim 1, wherein the prodder spring means is provided of a size and strength such that when the moveable plunger is adjacent to the starting position the prodder spring means is resistant, in use, to any further stretching such that further movement of the plunger toward the starting position will cause the prodder spring to pull the prodder away from the fluid outlet opening to break the prodder seal.

7. The apparatus according to claim 1, wherein the prodder spring means is provided in the valve assembly to provide both resistive pushing and pulling forces depending upon which part of the cycle of movement the movable components are in.

8. The apparatus according to claim 1, wherein the movable plunger is sized to move within the main chamber and is provided with sealing means to prevent free movement of fluid between the main chamber and the dose chamber.

9. The apparatus according to claim 1, wherein the movable prodder is sized to move within the dose chamber and is provided with a portion of its lowest end adjacent the fluid outlet opening defining an at least partially tapered cylinder profile.

10. The apparatus according to claim 1, wherein the fluid outlet opening is cylindrical and sized to form a convenient interference fit with the prodder.

11. The apparatus according to claim 1, wherein the fluid leak path is sized to facilitate a rate of fluid transfer between the chambers that is slower than a rate of fluid transfer from the container to the main chamber.

12. The apparatus according to claim 1, wherein a fluid inlet from the container into the main chamber of the assembly is at a substantially uppermost part of the main chamber and the fluid leak path to the dose chamber is at a substantially lowermost part of the main chamber, and the fluid leak path is located at the substantially uppermost part of the dose chamber and the fluid outlet opening is at the substantially lowest part of the dose chamber.

13. The apparatus according to claim 1, wherein the main chamber and the dose chamber are substantially cylindrical and are provided with substantially similar diameters, with the main chamber positioned directly above the dose chamber.

14. The apparatus according to claim 1, wherein the dose chamber is provided with a reduced diameter relative to the diameter of the main chamber.

15. The apparatus according to claim 14, wherein the main chamber is located above and at least partially surrounding the dose chamber wherein dose chamber walls are provided within the main chamber.

16. The apparatus according to claim 1, wherein an uppermost part of the main chamber is closeable by a moveable threaded top which can be screwed down to close or at least partially close fluid flow into the main chamber and/or to restrict movement of the plunger.

17. The apparatus according to claim 16, wherein there is a spring between the moveable threaded top and the plunger.

18. The apparatus according to claim 1, wherein, in use, the movable components in the valve assembly cycle movement between a starting position and a charging position, and in the starting position the movable plunger is at an uppermost position of travel when closest to a fluid inlet from the container, whilst the moveable prodder is also in its uppermost position in which the prodder does not form a seal with the fluid outlet opening, and wherein in the charging position the movable plunger and the movable prodder are located in their lowest positions such that the prodder creates the fluid-tight prodder seal with the fluid outlet opening.

19. The apparatus according to claim 1, wherein the fluid leak path is provided by a substantially centralised hole in the plunger and is provided with a restriction means in the main chamber which almost seals or partially seals the fluid leak path entrance to reduce the rate of fluid transfer between the chambers.

20. A method of using the apparatus of claim 1, wherein the method comprises deactivating the valve assembly to arrest the movement of the movable components and thus cease further spraying of fluid.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Embodiments of the invention will now be described, by way of example only, with reference to the following drawings in which:

(2) FIG. 1 illustrates a sectioned side view of an apparatus according to aspects 1-6 of the present invention in a start position; and

(3) FIG. 2 illustrates a sectioned side view of an apparatus according to aspects 1-6 of the present invention in a charging position.

(4) FIG. 3 illustrates a sectioned side view of an apparatus according to aspects 1-3 & 7-9 of the present invention in a start position;

(5) FIG. 4 illustrates a sectioned side view of an apparatus according to aspects 1-3 & 7-9 of the present invention in a charging position;

(6) FIG. 5 illustrates a section side view of an alternative apparatus according to aspects 1-3 & 7-9 of the present invention in a start position;

(7) FIG. 6 illustrates a section side view of an alternative apparatus according to aspects 1-3 & 7-9 of the present invention in a charging position; and

(8) FIG. 7 illustrates a section side view of an alternative apparatus according to aspects 1-3 & 7-9 of the present invention in a charging position.

DESCRIPTION OF AN EMBODIMENT

(9) Referring to both FIGS. 1&2, a non-electrically powered automatic dosing and spraying apparatus 1 is shown which comprises a valve assembly 2 and a container of pressurised fluid 3. The container of fluid 3 may be a standard aerosol canister with an outlet valve 6, wherein the valve assembly 2 is connected to the container 3 to open the outlet valve 6 to permit the fluid to flow into the valve assembly 2. The fluid flows through a fluid inlet 7 and into a main chamber 8 where the fluid meets a movable plunger 4 which is sealed via sealing means 9 against the inner walls of the main chamber 8. The plunger 4 is provided with a leak path provided by a centralised hole 10 (not shown) that travels the entire length of the plunger 4. The hole 10 may be covered by a restriction means (not shown) in the form of a flat washer or the like which almost seals the hole 10 against fluid flow into same. FIGS. 1&2 show a further leak path in the form of score line 10′ that travel between lines A and A′.

(10) The leak paths provided by hole 10, and score line 10′, lead to dose chamber 12 located directly below the main chamber 8 and is shown here with both chambers 8&12 having a substantially identical diameter and are formed from a singular chamber which is separated into the main chamber 8 and the dose chamber 12 solely by the contact point of the sealing means 9 against the walls of said singular chamber.

(11) In the dose chamber 12 there is housed a movable prodder 5 together with a main spring means provided by helical spring 13 and a prodder spring means provided by a helical spring 14. The main spring 13 is mounted on the lowermost part of the dose chamber 12 and contacts the lowermost part of the plunger 4 to bias against downward movement of the plunger toward the dose chamber 12. The prodder 5 is generally cylindrical and is provided with a portion of its lowest end adjacent a fluid outlet opening 15 defining an at least partially tapered profile to facilitate an ease of engagement and sealing with the fluid outlet opening 15. The prodder spring 14 is connected at one end to the plunger 4 and at its other end to the prodder 5. Coaxial with the prodder 5 is the fluid outlet opening 15 which is shown as a right angled opening but is preferably cylindrical and formed from a material that is at least somewhat flexible and sized to form a convenient interference fit with the tapered portion of the prodder 5.

(12) FIG. 1 shows the start position wherein the plunger 4 is at its uppermost position of travel when closest to a fluid inlet 7 from the container 3, whilst the prodder 5 is also in its uppermost position in which the prodder 5 does not form a seal with the fluid outlet opening 15. Whereas FIG. 2 shows the charging position wherein the plunger 4 and prodder 5 are at their lowest positions and the prodder 5 forms a prodder seal with the fluid outlet opening 15 which prevents any fluid in the dose chamber 12 from entering the fluid outlet opening 15.

(13) The main spring 13 is mounted coaxially with the prodder spring 14 and is sized to surround the prodder spring 14. The main spring 13 is carefully selected to ensure that has an overall spring strength that is weak enough to permit the plunger 4 to travel down the main chamber from a start position to a charging position when the plunger 4 is exposed to the fluid pressure from the container 3, whilst also being strong enough to act with the fluid pressure in the dose chamber 12 to return the moveable plunger 4 back to the start position at the end of a charging cycle, said cycle being described below. Thus the main spring 13 means is provided to provide resistive pushing forces only. The prodder spring 14 is provided of a size and strength such that when the plunger 4 is adjacent to the start position the prodder spring 14 is resistant to any further stretching such that further movement of the plunger 4 toward the start position will cause the prodder spring 14 to pull the prodder 5 away from the fluid outlet opening 15 thus breaking the prodder seal. The prodder spring 14 is provided to provide both resistive pushing and pulling forces depending upon which part of the cycle of movement the movable components are in.

(14) In operation the movable components cycle between the starting position and into the charging position during which a dose of fluid to be sprayed builds up before eventually releasing and spraying said dose whilst substantially simultaneously therewith or substantially immediately thereafter returning to the starting position to repeat the cycle.

(15) The operation cycle will be described in more detail hereinafter. Before the valve assembly is activated the movable components of the assembly 2 are in the starting position. Once the valve assembly 2 is activated, such as by unscrewing a threaded top or the like, fluid flows from the container 3 through the fluid inlet 7 and into the main chamber 8. As the pressure of the fluid bears against the plunger 4 only a very small quantity of the fluid is able to enter the the leak paths provided by hole 10 and score line 10′ and, therefore, much like the wind pushes a sail on a yacht with a small hole in it, the remainder of the fluid pushes the plunger 4 downwards against the force of the main spring 13. The downward movement of the plunger 4 causes downward movement of the prodder spring 14 which is mounted on the prodder 5 and cause the downward movement of the prodder 5. Alternatively or additionally, the plunger 4 may directly contact the prodder 5 to effect or assist the downward movement thereof until the prodder 5 makes sealing engagement with the fluid outlet opening 15. Once the prodder seal is made, the movable components are then in the charging position and a dose of fluid begins to build in the dose chamber 12.

(16) Once the prodder seal is made and the charging position arrived at, the dose chamber 12 begins to fill with fluid which initiates the return stroke of the cycle back to the starting position. During the return stroke the dose chamber 12 slowly fills with fluid from the leak path provided by hole 10 and since the fluid cannot escape past the prodder seal, this building volume of fluid causes the plunger 4 to move toward its uppermost position, the main spring 13 assists this upward movement. During the return stroke the prodder 5 remains engaged with the fluid outlet opening 15 until the plunger 4 is immediately adjacent to its uppermost position (i.e. the starting position) wherein the plunger 4 is immediately adjacent to the at least partial groove 17, and specifically a tapered portion 18 of said groove 17, in the main chamber 8 and the fluid is able to escape from the main chamber 8 into the dose chamber 12 via said groove 17 thus very briefly permitting the dose chamber 8 and the leak path provided by score line 10′ which is a superimposed score line, to be exposed to the full fluid pressure of the container 3. The momentary exposure to the full container pressure causes all of the movable components of the assembly 2 to be in their uppermost position which is the starting position and the cycle starts again and the fluid pressure acting on the plunger 4 moves the plunger 4, much like wind pushes a sail on a yacht with a small hole in it, downwards away from the groove stopping further fluid using same to enter the dose chamber 12 and allowing the prodder 4 to move downwards into sealing engagement with the fluid outlet opening 15 to re-create the prodder seal and the charging position is arrived at and the dose chamber can again begin to slowly fill with fluid.

(17) Referring to both FIGS. 3&4, a non-electrically powered automatic dosing and spraying apparatus 1′ is shown which comprises a valve assembly 2′ and a container of pressurised fluid 3′. The container of fluid 3′ may be a standard aerosol canister with an outlet valve 6′, wherein the valve assembly 2′ is connected to the container 3′ to open the outlet valve 6′ to permit the fluid to flow into the valve assembly 2′. The fluid flows through a fluid inlet 7′ and into a main chamber 8′ where the fluid meets a movable plunger 4′ which is sealed via sealing means 9′ against the inner walls of the main chamber 8′. Extending from the uppermost part of the main chamber 8′ is timer pin 22 in the form of an elongate protrusion, the timer pin 22 is non-centrally located within the main chamber 8′. The plunger 4′ is provided with a leak path provided by a centralised hole 10′″ that travels the entire length of the plunger 4′. The hole 10′″ is covered by a ball 11 which sits in ball seat 23 to almost or partially seal the hole 10 against fluid flow into same.

(18) The leak path provided by hole 10′″ leads to dose chamber 12′ located directly below the main chamber 8′ and is shown here with both chambers 8′&12′ having a substantially identical diameter and are formed from a singular chamber which is separated into the main chamber 8 and the dose chamber 12′ solely by the contact point of the sealing means 9′ against the walls of said singular chamber.

(19) In the dose chamber 12′ there is housed a movable prodder 5′ together with a main spring means provided by helical spring 13′ and a prodder spring means provided by a helical spring 14′. The main spring 13′ is mounted on the lowermost part of the dose chamber 12′ and contacts the lowermost part of the plunger 4′ to bias against downward movement of the plunger toward the dose chamber 12′. The prodder 5′ is generally cylindrical and is provided with a portion of its lowest end adjacent a fluid outlet opening 15′ defining an at least partially tapered profile to facilitate an ease of engagement and sealing with the fluid outlet opening 15′. The prodder spring 14 is connected at one end to the plunger 4′ and at its other end to the prodder 5′. Coaxial with the prodder 5 is the fluid outlet opening 15′ which is shown as a right angled opening but is preferably provided as shown in FIG. 5 being cylindrical, formed from a material that is at least somewhat flexible and sized to form a convenient interference fit with the tapered portion of the prodder 5′.

(20) FIG. 3 shows the start position wherein the plunger 4′ is at its uppermost position of travel when closest to a fluid inlet 7′ from the container 3′, whilst the prodder 5′ is also in its uppermost position in which the prodder 5′ does not form a seal with the fluid outlet opening 15′. Whereas FIG. 4 shows the charging position wherein the plunger 4′ and prodder 5′ are at their lowest positions and the prodder 5′ forms a prodder seal with the fluid outlet opening 15′ which prevents any fluid in the dose chamber 12′ from entering the fluid outlet opening 15′.

(21) The main spring 13′ is mounted coaxially with the prodder spring 14′ and is sized to surround the prodder spring 14′. The main spring 13′ is carefully selected to ensure that has an overall spring strength that is weak enough to permit the plunger 4′ to travel down the main chamber from a start position to a charging position when the plunger 4′ is exposed to the fluid pressure from the container 3′, whilst also being strong enough to act with the fluid pressure in the dose chamber 12′ to return the moveable plunger 4′ back to the start position at the end of a charging cycle, said cycle being described below. Thus the main spring 13′ means is provided to provide resistive pushing forces only. The prodder spring 14′ is provided of a size and strength such that when the plunger 4′ is adjacent to the start position the prodder spring 14′ is resistant to any further stretching such that further movement of the plunger 4′ toward the start position will cause the prodder spring 14′ to pull the prodder 5′ away from the fluid outlet opening 15′ thus breaking the prodder seal. The prodder spring 14′ is provided to provide both resistive pushing and pulling forces depending upon which part of the cycle of movement the movable components are in.

(22) In operation the movable components cycle between the starting position and into the charging position during which a dose of fluid to be sprayed builds up before eventually releasing and spraying said dose whilst substantially simultaneously therewith or substantially immediately thereafter returning to the starting position to repeat the cycle.

(23) The operation cycle will be described in more detail hereinafter. Before the valve assembly is activated the movable components of the assembly 2′ are in the starting position. Once the valve assembly 2′ is activated, such as by unscrewing a threaded top as discussed below in reference to FIG. 5, fluid flows from the container 3′ through the fluid inlet 7′ and into the main chamber 8′. As the pressure of the fluid bears against the plunger 4′ only a very small quantity of the fluid is able to enter the hole 10′″ of the leak path via the gap between the ball 11 and the ball seat 23 and, therefore, much like the wind pushes a sail on a yacht with a small hole in it, the remainder of the fluid pushes the plunger 4′ downwards against the force of the main spring 13′. The downward movement of the plunger 4′ causes downward movement of the prodder spring 14′ which is mounted on the prodder 5′ and cause the downward movement of the prodder 5. Alternatively or additionally, the plunger 4′ may directly contact the prodder 5′ to effect or assist the downward movement thereof until the prodder 5′ makes sealing engagement with the fluid outlet opening 15′. Once the prodder seal is made, the movable components are then in the charging position, as shown in FIG. 4, and a dose of fluid begins to build in the dose chamber 12′.

(24) Once the prodder seal is made and the charging position arrived at, the dose chamber 12′ begins to fill with fluid which initiates the return stroke of the cycle back to the starting position. During the return stroke the dose chamber 12′ slowly fills with fluid from the leak path provided by hole 10′″ and since the fluid cannot escape past the prodder seal, this building volume of fluid causes the plunger 4′ to move toward its uppermost position, the main spring 13′ assists this upward movement. During the return stroke the prodder 5′ remains engaged with the fluid outlet opening 15′ until the plunger 4′ is immediately adjacent to its uppermost position (i.e. the starting position) the timer pin 22 makes contact with an off-centre part of the ball 11 and urges the ball 11 out of partial or almost sealing engagement with the ball seat 23 and very briefly permit the dose chamber 12′ and/or the hole 10′″ to be exposed to the full fluid pressure of the container 3′. The brief exposure to the full container pressure achieves at least two important functions; firstly it provides a final and rapid expansion of the dose chamber 12′ which ensures that the prodder seal is broken permitting the fluid in the dose chamber 12′ to pass into the fluid outlet opening 15′ and be sprayed into the environment surrounding the assembly 2′. Secondly, the brief exposure momentarily exposes the hole 10′″ to the full can pressure imparts a self-cleaning function whereby any particulate matter built up in the hole 10′″ is swept away into the dose chamber 12′ or out the assembly 2′ via the fluid outlet opening 15′. The momentary exposure of the hole 10′″ and dose chamber 12′ to the full container pressure causes all of the movable components of the assembly 2′ to be in their uppermost position which is the starting position and the cycle starts again and the fluid pressure acting on the plunger 4′ moves the plunger 4′, much like wind pushes a sail on a yacht with a small hole in it, downwards which allows the ball 11 to move away from the timer pin 22 and again almost seal or partially seal against the ball seat 23 and allows the prodder 4′ to move downwards into sealing engagement with the fluid outlet opening 15′ to re-create the prodder seal and the charging position is arrived at and the dose chamber can again begin to slowly fill with fluid.

(25) Turning to FIGS. 5-7 an alternative embodiment is shown wherein the principle differences are that dose chamber walls 24 are provided to reduce the size of the dose chamber and the timer pin 22′ is provided by a bulbous protrusion extending from one side of an upper portion of the main chamber 8′. In this embodiment plunger 4″ may be provided with at least one of sealing means 9′ similar to those in the first embodiment but is preferably or alternatively provided with sealing means 25 between the plunger 4″ and the dose chamber walls 24.

(26) The uppermost part of assembly housing may be provided with a movable threaded top 19. The main chamber 8′ is defined between the threaded top 19 and the plunger 4″. The threaded top 19 may be screwed downwardly until it seals closed the fluid inlet 7′. In this arrangement, a user may activate the apparatus by unscrewing the threaded top 19 to permit fluid in the fluid inlet 7′ to pass into the main chamber 8′ and initiate the cycle between the starting position and the charging position.

(27) A ball spring means 20 provided by a helical spring is arranged between the ball 11 and the treaded top to assist in ensuring a suitable almost or partial seal between the ball 11 and the valve seat 23 to restrict fluid flow from the main chamber 8 into the hole 10.

(28) The operation cycle as described above is shown in FIGS. 5-7, wherein the starting position is shown in FIG. 5 wherein the prodder 5″ is not in sealing engagement with the fluid outlet opening 15′, the plunger 4″ is in its uppermost position and the bulbous timer pin 22 is in contact with one side of the ball 11 to ease the ball 11 out of almost or partial sealing with the ball seat 23. FIG. 6 shows the when the assembly has first arrived at charging position from the starting position of FIG. 5, here it can be seen that the plunger 4″ directly contacts the prodder 5″ to urge same into the fluid outlet opening 15′ to create the prodder seal. Turning to FIG. 7 the build up of fluid in the dose chamber 12′ can be seen just before the ball 11 contacts the timer pin 22 to return the assembly back to the orientation shown in FIG. 5.

(29) A particulate filter 21 is shown, this is present to reduce or prevent the passage of particulate matter into the main chamber and further into the valve assembly thus reducing the likelihood of the device tending toward blockage and/or failure.

(30) All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

(31) Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

(32) The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.