The present invention relates to a valve for an aerosol canister or a pressurised vessel. More particularly, but not exclusively, this invention relates to a simple modification to a standard aerosol canister valve and diptube to convert it into a dosing or safety valve. In another variation this invention relates to a simple modification to a standard aerosol canister valve and diptube to convert it into a flow control valve. Even more preferably, this invention relates to a combination of the improved valve and diptube and a nozzle arrangement that is adapted to be fitted to an outlet of an aerosol canister or a pressurised vessel to convert it from a manually operated device into an automatic device that automatically discharges a set number of times per hour or day.

According to a first aspect of the invention there is a modified valve arrangement for a pressurized dispenser 105 comprising a container with a dispensing valve 106 and a diptube 104, a flow control component 111 inside the diptube 104, a pressurized dispensing fluid, wherein the diptube 104 has a retaining feature 103 that retains the flow control component 111 in the diptube and the flow control component 111 can move along the diptube 104 and in normal operation the flow control component 111 is clear of the valve 107 but whether the container is upright, angled or inverted, the flow control component can move to a position where it makes contact with the valve 107 and forms a slow leak path between it and the downstream end of the valve 107 and wherein the valve arrangement controls the volume of fluid leaving the pressurized dispenser 105. According to a second aspect of the invention there is a modified version of the invention described in the first aspect that controls the rate of flow and the volume of fluid leaving the pressurized dispenser.

According to a third and preferred aspect of the invention there is a modified version described in the first and second aspects wherein the valve outlet from said invention is connected to the inlet of an automatic spray device that automatically delivers timed discharges of fluid with no manual input and wherein the flow control component 111 is normally clear of the valve inlet 108 and has no effect on the automatic spray device but moves to and contacts the valve inlet 108 forming an almost seal and greatly reduces the flow to the automatic spray device if the automatic spray device is inverted, or fails and tries to deliver too much liquor over a set period of time.

Valves are used in aerosol or pressurized canisters to enable the canisters to be filled with fluid and to retain that fluid until the top or stem 109 of the valve is depressed by an actuator allowing the fluid to flow continuously from the canister through a diptube attached to the valve and through the valve until the valve is released closing it off. For some applications there is a need to deliver a dose or set volume of fluid with each depression of the actuator whereby no more fluid will be delivered until the actuator is released and then depressed again. The current dosing valves work well and are reliable but cost is very critical with aerosols and this invention is cheaper although not as precise. Nozzle arrangements such as actuators are commonly used to facilitate the dispensing of various fluids from containers or vessels. For instance, nozzle arrangements are commonly fitted to pressurised fluid filled vessels or containers, such as a so called "aerosol canister", to provide a means by which fluid stored in the vessel or container can be dispensed.

A typical nozzle arrangement comprises an inlet through which fluid accesses the nozzle arrangement, an outlet through which the fluid is dispensed into the external environment, and an internal flow passageway through which fluid can flow from the inlet to the outlet. In addition, conventional nozzle arrangements comprise an actuator means, such as, for example, a manually operated aerosol canister. The operation of the actuator in the active phase means causes fluid to flow from the container to which the arrangement is attached into the inlet of the arrangement, where it flows along the fluid flow passageway to the outlet.

Almost all aerosol canisters are actuated manually by pressing on the actuator 110 but recently automatic aerosol devices have become fairly widespread for products including insecticides, air freshener, air treatments etc. These take many forms but are usually mains or battery operated and use solenoid valves, timers and sensors to act on the valve of the aerosol canister to cause it to actuate throughout the day. Refills are supplied for the devices in the form of aerosol canisters. Some work on a simple timed device so they automatically spray every 5 - 30 minutes or so whilst others use sensors that detect movement nearby and then release a dosed spray. These devices are expensive to manufacture and are normally sold at a loss and the companies then make high profits on the refill aerosol cans much like ink jet printers are sold at a loss so the companies can make money on the replacement inks.

Whilst this approach works well it would be much better if an automatic device could be made so cheaply that there was no need for refills and the spent aerosol cans could simply be disposed of as normal.

Our invention covered in our patent application PCT/GB2013/000319 has solved many of the problems highlighted above with an automatic dispenser that is only powered by the compressed gas of the canister and is adapted to be fitted to a pressurised vessel or container and keeps the valve stem permanently depressed and consequently, the valve open. Other companies have also tried to develop automatic aerosol devices that use only the power of the compressed gas in the canister and more will doubtless be developed.

A problem with many of the automatic devices including one of ours shown in figure 4 is that that the valve 6 in the container 3 needs to be open all of the time. Since the gas is often a voc such as butane this has the potential for causing problems. If the device is accidentally inverted or something goes wrong with the device then the contents of the canister 3 could be discharged in a short period of time delivering unacceptable amounts of the product and gas into the room. That would be bad enough with air freshener but it could be serious with insecticide. In the event of a fire in the room it could potentially become like a flame thrower. So what is needed is a valve that prevents the free throw of the fluid in the event of failure of the nozzle arrangement. It also needs to allow the nozzle arrangement to fill when first used or if reused at a later date. In addition, it needs to be really simple and cheap as valves are ridiculously inexpensive.

A standard dosing valve wouldn't work because it needs to be reset once the dose has been delivered and consequently it wouldn't fill the device the first time and it wouldn't be able to replace the fluid discharged in a dose because it wouldn't reset. What is needed is a valve that would enable enough fluid to be delivered to the device when it is first used or reset and then to be able to deliver enough to the device during the normal operation and finally, to be able to close off the valve or to almost close it off if the device fails or part fails. But we don't want to design a new valve because the costs involved would mean that it simply wouldn't be viable.

So our answer for all of the problems highlighted above was to take a standard valve 106 and diptube 104 and simply add a ball, disc, tapered rod or appropriate shaped part inside the diptube 104 as shown in figures 1 and 4. We will refer to this part as a flow control component 111. This is retained inside the diptube by either crimping the diptube in an appropriate position below the flow controller or inserting something like a tube inside the diptube or by adding something onto the downstream end of the diptube. Basically, in the preferred versions the flow control component is able to move between a downstream position and an upstream position with the maximum upstream position putting it in contact with the aerosol valve inlet where it normally forms an almost seal preventing all but a minimum amount of fluid to pass it in the almost seal position. Some fluid is normally allowed to pass between the flow control component and the diptube and the flow control element will only reach the almost seal position once the preset volume of fluid has been discharged. For the versions where the valve is connected to an automatic discharge device the almost seal position will only be reached in the event of failure of said device and will then reset if the device starts to work correctly with the flow control component falling away from the almost seal position. For the dosed discharge version the flow control component will fall back to the downstream position once the outlet valve is closed by the user releasing the actuator.

The flow control version works differently in that the flow control component moves from a downstream position to an upstream position where it contacts the valve inlet but then forms a flow control position between it and the valve inlet as opposed to an almost seal position. There is also little or substantially no fluid that passes between the flow control component and the diptube as it moves to the valve inlet.

The operation will now be described in more detail.

Figure 1 is a cross-sectional view though an aerosol canister with the flow control component and a crimped diptube.

Figure 2 is a view similar to that of Figure 1 but showing the flow control component in contact with the valve. Figure 3 is a cross-sectional view showing the valve and top of the diptube and various fluid flow components.

Figure 4 is a cross-sectional view though an aerosol canister with the flow control component and a crimped diptube connected to an automatic dispenser.

In figures 1 and 2 we see an aerosol canister 101 with a valve 106, actuator 110 and a diptube 104 on the spigot 107 of the valve 106. There is a ball 111 that acts as the flow control component 111 in the diptube 104 resting on the deformation 103 in the diptube 104 caused by crimping and the ball 111 cannot fall out of the diptube because of it. In figure 2 the ball 111 is against the downstream end inlet hole 108 of the valve 106 creating either an almost seal or a flow path between the two parts. This is shown better in figure 3a. In figure 3b we see a conically tapered rod 302 with a tapered downstream end that goes into the input hole 108 of the valve 106 and like the ball 111 forms an almost seal or a flow path between it and the rim of the hole 108. In figures 3c and 3d we see a round flat disc 301 on the edge of the hole 108 which has a groove 304 that forms a leak path between the two parts. These are just 3 examples and any suitable shape could be used and the rim or end of the hole 108 could also be shaped in any suitable way.

When the actuator 110 is pushed down the valve stem 109 is also moved and this opens the valve 106 allowing fluid in the diptube 104 and above the ball 111 to go the valve 106 and actuator 110. As it does the ball 111 moves higher up the diptube and if the flow is long or high enough it will go to the almost sealing position against the valve as in figure 2. There is a gap 303 between the ball 111 and diptube 104 and as the ball moves so some fluid can pass from the canister 105 to go through the diptube 104, past the ball 111 and through the valve 106 and actuator 110. In the dosing valve version, this gap 303 is sized to ensure that the total volume discharged from the valve 106, diptube above the ball 111 and fluid passing the ball 111 equals the discharge required. If the gap 303 is tiny then very little if any fluid will pass as the ball 111 moves to its almost sealing position. Once the actuator 110 is released the valve 106 closes and the pressure upstream and downstream of the ball 111 will equalize allowing the ball 111 to drop back down to the crimped position 103. Any means of preventing the flow control device 111 moving too far upstream could be used instead of crimping the diptube 104 and examples include inserting a part such as a hollow tube into the diptube 104 so the top of it is positioned where the crimp would be.

The downstream end of the valve 108 is tubular and the flow control component 111 almost preferentially but not exclusively seals against either the inside of the rim of the tube or on the flat of the end of the tube. Since the valve 106 is normally made of a rigid plastic such as polyethylene or polypropylene and the flow control component 111 is normally made of metal, glass or a hard plastic the flow control component 111 doesn't normally form a seal against the valve inlet 108 anyway. But the flow past it can be reduced by making the surface of the valve inlet 108 and especially the inside rim of the hole accurately and a very low leak can be formed this way. The flow control component 111 could even be made out of a softer plastic such as Idpe or rubber or an O ring could be added to the hole. Conversely, if a larger leak is required then the surface of the hole or flow control component 111 can be roughened or a fine groove, indent or recess could be added. The point is that any leak rate required can be achieved.

With the flow control version the crimped position 103 is normally much closer to the valve inlet 108 so that the ball 111 doesn't fall very far and consequently goes almost immediately next to the valve inlet 108 so that there is a fairly constant flow through the leak paths between them regardless of pressure. In figure 3d we see a small groove 304 in the side of the rim of the hole 108 and the disc 301 both almost seals the hole 108 and deforms into the groove 304. At high pressure it seals the valve inlet 108 more effectively and pushes further in the groove 304 that it does at low pressures. By carefully designing the parts and leak path a fairly constant flow can be achieved regardless of the pressure. The disc 301 needs to be resiliently deformable to allow the deformation and its hardness is an important factor in the way it deforms. The groove could be in the disc 301 instead of the valve inlet 108 and it could be any suitable indentation or even raised features such as ribs. The disc 301 could even be made in a rigid plastic and the end part of the inlet 108 could be made in a resiliently deformable plastic.

When aerosols use butane or other vocs the pressure in the canister is very similar for most of the canister life but for compressed gas or air the pressure reduces considerably over the lifetime of the canister. This is a big problem with standard aerosol canisters as the flow reduces enormously as the canister empties and can easily halve but it doesn't apply to aerosol canisters delivering a set dose. The reduced flow also causes the spray or foam quality to deteriorate. The flow control component 111 can be used to control that flow to within 15 - 20% or thereabouts as the canister empties by forming a flow control device on the downstream end of the valve 108 as above. The flow control component 111 can fall back to the crimp position between uses and this enables the arrangement to clean itself as any debris on the underside of the valve 106 can fall away.

As the pressure reduces so there is less force on the flow control component 111 on the valve 106 and more fluid can pass it and this keeps the flow fairly constant with pressure. But for higher flows you really need to put a tiny V, groove or indent in the valve inlet 108 or the flow control component 111 so the fluid can flow through that. But once you use a leak feature it becomes difficult to maintain the same flow with different pressures as the flow control component 111 cannot affect the size of the leak feature. So you would then use a flexible flow control component 111 so that it can push further into the recess with higher pressures and this maintains a constant gap size and therefore a constant flow with pressure. Once you use a flexible part then you can also use a raised feature on the valve inlet 108 instead of a recess. The point is to create a leak path between the valve inlet 108 and the flow control component 111 that can be altered by the flow control component 111 being pushed harder or softer by the higher or lower fluid pressure so that the leak stays fairly constant with the change in pressure. The size of the flow control component 111 relative to the diptube 104 is no longer critical here and neither is the position of the crimped feature 103 except that you want the crimp 103 to be positioned so that the flow control component 111 can drop away from the valve 106 when the valve 106 is off.

For a simple dosing valve, the device is set with a fine gap around the flow control component 111 and the volume downstream of the flow control component 111 is the dose required. When the valve 106 is opened by depressing the actuator 110 the contents of the valve 106 and diptube 104 are discharged and the flow control component 111 follows the fluid dose and almost seals against the downstream end of the valve 108 stopping all but a tiny discharge. Some fluid may pass the flow control component 111 as it moves up but this would be tiny in the simple version and can be allowed for when setting the initial position of the flow control component 111 with the crimp position 103 in the diptube 104. If there was no leak between the flow control component 111 and valve inlet 108 then the pressure upstream of the flow control component 111 would always be higher than that downstream of it so that once it was closed the flow control component 111 would stay in position rendering the device useless. Releasing the actuator 110 enables the valve 106 to close and the flow control component falls back down to the starting position enabling a second dose to be discharged once the actor is depressed again.

Often the diptube 104 doesn't hold enough fluid for the required dose so sizing the flow control component 111 can allow additional fluid to pass the flow control component 111 increasing the dose before the flow control component 111 reaches its almost seal position. So each dose will be very similar to each other in volume and would be the volume in the valve 106 plus that of the diptube 104 downstream of the flow control component 111 plus any fluid passing the flow control component 111 as the flow control component 111 moved to the almost sealing position.

Figure 4 shows an aerosol can 3 with the modified valve arrangement and an automatic spray dispenser 1 is fixed on the outlet valve 6. This dispenser and other versions are covered in our patent application PCT/GB2013/000319 and it is only given as one of many possible examples that can be used with the modified valve arrangement. So for full details of how it works then see said patent.

Basically, the outlet valve 6 of the aerosol can 3 is fixed open so the fluid flows from the aerosol can 3 through the outlet valve 6 and into the chamber 8 of the automatic dispenser. It then passes through a slow leak path between the ball 11 and plunger 5 into the channel 10 and into the dose chamber 12. The device is actually shown as fluid is being sprayed from the dose chamber 12 through the chamber outlet 15 and though the spray orifice 16. This spray lasts for a fraction of a second and as the fluid is discharged from the dose chamber 12 so the plunger 5 and prodder 4 rapidly move back downstream until the prodder 4 seals the outlet hole 15 and the spray stops. More fluid enters into the dose chamber 12 via the leak path between the ball 11 and plunger 5 and as it fills the dose chamber 12, the plunger 5 moves upstream under the action of the main spring 13 and stretches the prodder spring 14. Eventually the tension in the prodder spring 14 is too strong and it pulls the prodder 4 away from the sealing hole 15 allowing the fluid to escape from the dose chamber 12 and being sprayed out of the spray orifice 16. The process keeps repeating itself until the device is turned off or the can 3 is empty. Varying the size of the dose chamber 12, the strength of the springs 13 and 14 and the movement of the plunger 5 all varies the dose. Varying those plus the size of the leak path between the ball 11 and plunger 5 varies the time of the dose.

If there is a failure of the prodder 4 sealing properly in the chamber outlet hole 15, or the leak path becomes too big for whatever reason, or a seal fails or some other part fails then the fluid from the aerosol can 3 could be rapidly discharged. But the modified valve arrangement prevents that by allowing enough fluid to pass from the aerosol can 3 to fill the chambers 8 and 12 for a limited number of times in a period of time before closing the flow control component 111 sealing off the outlet from the diptube 104 in the can 3. Either the outlet valve from the aerosol can 3 or the flow from the automatic spray dispenser would need to be manually closed and then reopened to allow the flow control component 111 in the diptube 104 to open enabling fluid to flow again.

With the automatic spray versions there is no actuator 110 and the valve 106 is joined to the inlet of the automatic device as shown. In some versions the valve 106 is held permanently open and in others a solenoid valve pushes the valve 106 down to open at the required time. For the automatic dispenser devices the amount of fluid required to fill the device the first time it is used or when it is reset is often much more than the dose itself because of dead space in the device and the flow control component 111 and diptube 104 and crimped position are designed to be able to accommodate this volume and usually more as a safety margin. So that there is more than enough fluid allowed to be delivered before the flow control component 111 reaches the almost seal position. During normal operation of the device a very low flow of liquor passes through the valve from the canister 101 and the flow control component 111 stays well clear of the almost seal position and usually stays on the crimp position 103. The fluid simply flows past the flow control component 111. If the discharge increases from the automatic device and consequently through the diptube 104 then the flow control component 111 will move up higher in the diptube 104 to reflect the increased flow. If it is only a small increase then the flow control component 111 may be sized so as not to move at all. If the discharge from the device increases by too much then the flow control component 111 will go to the almost sealing position and let very little fluid through. If the device settles down and starts delivering the correct discharge or thereabouts then the flow control component 111 will drop away from the almost sealing position. If the flow through the almost seal position is less than through the device then the flow control component 111 cannot drop away from the almost sealed position because the pressure downstream of it is lower than the pressure upstream of it. So control of the leak rate through the almost sealed position determines the maximum flow to the device once the flow control component 111 has formed the almost seal. Since this is low very little fluid can be discharged from the device if it fails in some way. But a much higher flow to the device is possible before the flow control component 111 reaches the almost seal position and the amount of fluid discharged before that position can be accurately controlled by varying the size, weight, material and shape of the flow control component 111 plus the gap between it and the diptube 104.

If something goes wrong with the device and it starts spraying too quickly or with too much fluid the flow control component 111 will go to the top of the diptube 104 and will almost seal against the valve inlet 108 so that very little fluid can escape. The device may empty itself but they don't hold very much so that isn't a problem. If it starts working properly again then the pressures upstream and downstream of the flow control component 111 will equalize and the flow control component 111 will drop back down. If the device starts delivering more than required or more often than required then the flow control component 111 will rise just like in a flow meter because more fluid is called for than can pass it. You can set the gap or design the flow control component 111 in such a way that if say more than anywhere from 30% - 500% more is delivered than required the flow control component 111 goes to the almost seal position but if less than that is delivered the flow control component 111 won't reach the almost sealing position. But any volume could be chosen and maybe even as high as 1000% or more.

If the device is knocked over, tilted or inverted, the flow control component 111 will go to the almost sealing position making the valve 106 safe because it takes less flow to enable it to move in a tilted or inverted diptube 104 than in a vertical diptube 104 and it cannot fall away after. If it is then placed upright it will work as before. This is a very complex action that has been achieved with a simple modification to a standard valve and diptube.

Where the flow control component 111 has been described as a ball, disc or shaped rod it could be any of these or any suitable alternative.

The invention described can be used to produce a spray, foam or bolus of liquor from pressurized containers, pumps or triggers. Similarly, the versions that are connected to an automatic dispenser can also produce a spray, foam or bolus of liquor.

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.