Patent Application
20150209465
This invention relates to dispensing of volatile materials, in particular to an emanator, and a system using the emanator, for dispensing such materials.
Emanators and systems using emanators for dispensing volatile materials, for example room fragrances, insecticides, or the like, are known in the art and come in different forms. This invention relates to a type of emanator supplied from a reservoir of volatile fluid.
Known emanators however have a number of problems associated therewith, in particular known emanators have poor linear release of material, are known to become progressively blocked, the consistency of the emanated product is not maintained over time, and, due to poor emanation, liquid within the reservoir is often discarded at service intervals.
Linear release of material from the emanator is highly desirable as it ensures that a constant performance can be delivered from the emanator. This is beneficial irrespective of the use of the emanator. In, for example, room fragrance delivery it is highly beneficial for the emanator to deliver the same fragrance at substantially the same rate at the end of its life as it is does towards the beginning of its life. When, for example, used for insecticide release it is highly desirable that a linear release of insecticide is achieved over time, thus ensuring effectiveness over the life of the product.
One known design of reservoir which goes some way to addressing some of the known problems associated with emanators is disclosed in International patent application WO 01/77004. This document discloses a pressure compensated dispensing reservoir that assists in delivering linear release of material therefrom by removing or minimising hydrostatic pressure differences over the life of the device by creating and maintaining a substantially constant pressure head in the reservoir which is independent of the height of the liquid therein. However the methods of dispensing the material therefrom do not produce a highly linear output or need interference from an electrically controlled system (for example as disclosed in International patent application WO 01/66158) in order to regulate the dispensing of material therefrom.
The present invention seeks to provide an improved emanator and emanator system.
According to a first aspect of the invention there is provided an emanator for a volatile material, the emanator comprising: an elongate element having a first plurality of fibres distributed along its length and extending substantially perpendicular thereto; and a fluid pathway for the conveyance of volatile material along the emanator, said pathway comprising one or more second fibres substantially extending in a direction along the length of the element.
The first plurality of fibres may comprise a plurality of short fibres attached to a central core. The core may comprise two or more twisted wires and said first plurality of fibres can be retained between said two or more twisted wires.
The one or more second fibres may comprise one or more fibres extending continuously along the core of the element. The second fibres may follow the same twist as the wires. The number of second fibres can be chosen dependent upon whether a low or high output of fragrance is required. For example, the one or more second fibres may comprise one, two three, four, five, six, seven, eight, nine, ten or more fibres, with a low number of fibres being chosen for a low output device, or a higher number being chosen for a greater output.
Optionally the one or more second fibres can be coiled around the core.
In one embodiment of the invention the one or more second fibres deform some of the first fibres such that they extend along the length of the element in an overlapping fashion.
The second fibres can comprise a plurality of strands of polyester or of cotton polyester. The fluid pathway may comprise a capillary pathway. The first plurality of fibres may be polyester.
In a further embodiment the one or more second fibres comprise a subset of said plurality of first fibres, the subset deformed so as to substantially extend in a direction along the length of the element perpendicular to the remainder of the first plurality of fibres.
The emanator may be configured into a shape in which the total length of the flow path of the emanator is greater than the largest dimension of the space envelope occupied by said emanator. The emanator may have a length of between 80 cm and 1.2 m, or between 90 cm and 1.1 m, or be approximately 1 m, and the largest dimension of the space envelope occupied by said emanator may be in the region of 5 to 15 cm, or 7 to 12 cm, or 9 to 11 cm, or approximately 10 cm, for example. The emanator may be configured into one of: a spiral, a conical spiral, a square spiral, a helical coil, and Archimedean spiral.
According to a second aspect of the invention there is provided a system for releasing a volatile material into a room, the system comprising: at least one emanator according to the first aspect of the invention; a fluid reservoir for a volatile material; and a fluid delivery system for delivering fluid from said reservoir to said emanator.
The fluid delivery system may be configured to deliver a volatile fluid to a first end of the at least one emanator, and the at least one emanator may extend downwardly from the first end. Optionally the at least one emanator extends downwardly in a coil around the exterior of the reservoir. Alternatively the fluid delivery system can be configured to deliver a volatile fluid to a first end of the at least one emanator, and the at least one emanator can extend outwardly form the first end in a substantially horizontal plane.
The reservoir can be a pressure compensated reservoir configured to maintain a substantially constant head pressure irrespective of the fluid level within the reservoir.
The emanator may be terminated at one or each end with a sleeve, which may be a thin, and/or permeable sleeve. The sleeve may take the form of a fibrous rod made, and/or may be formed from polyolefine. The sleeve, when placed on an end of the emanator, preferably flattens the first fibres at the emanator end, ensuring the second fibres make good contact with the fluid delivery system.
In an embodiment of the invention the system further comprises a means of creating relative movement between the at least one emanator and the air surrounding it. The means of creating relative movement can comprises a fan configured to move air past the at least one emanator. Optionally the fan may be configured to draw air in an upwards direction over past the at least one emanator. Alternatively the means of creating relative movement may comprise means, for example a motor and gears, for rotating the at least one emanator. In a further alternative arrangement the means of creating relative movement may comprise a means for repeatedly imparting a magnetic field upon the emanator to cause it to oscillate. The means of imparting a magnetic field may comprise an electromagnetic coil and a controller to drive said coil so as to provide a pulsed magnetic field acting on said emanator.
In the system of the invention the at least one emanator may further comprise an absorbent mass at the distal end thereof. Preferably the absorbent material is a pad and, more preferably, the absorbent material is a cellulose pad. In an embodiment, the cellulose pad may have a thickness of approximately 3 mm, although pads of other thicknesses, e.g. between 2.5 mm and 3.5 mm may also be utilized. The pad is preferably positioned so that no part of it is below the constant level reservoir. The pad may be oriented in a horizontal plane to avoid creating a hydrostatic head. In another arrangement the absorbent mass may comprise a continuous plurality of sections of the elongate element arranged such that perpendicularly extending first fibres of one section intermesh with the perpendicularly extending first fibres of at least one other adjacent section. In an alternative arrangement the absorbent mass may comprise an absorbent material adjacent the end of the at least one emanator and in contact therewith.
In an embodiment of the invention the fluid delivery means can further comprise a mechanical diverter to divert a flow path for volatile material from the reservoir to none, one, or more than one, of the at least one emanators.
An enclosure may be provided as part of the system for enclosing at least the reservoir and at least one emanator, the enclosure being provided with vents to allow the flow of air into and out of the enclosure.
According to a third aspect of the invention there is provided a system for releasing a volatile material into a room, the system comprising at least one emanator comprising: an elongate element having a first plurality of fibres distributed along its length and extending therefrom; and a fluid pathway for the conveyance of volatile material along the emanator, said pathway comprising one or more second fibres substantially extending in a direction along the length of the element; a fluid reservoir for a volatile material; and a fluid delivery system for delivering fluid from said reservoir to said emanator.
In embodiments, the first plurality of fibres comprises a plurality of short fibres attached to a support which runs along the length of the emanator. The one or more second fibres may comprise one or more fibres extending continuously along the support. The support may be polyester. The second fibres may be attached to the surface or at least partially embedded of the polymer material, and said first fibres may extend from the surface of the polymer layer on which the second fibres are attached.
It will be appreciated that any of the optional features of the third aspect of the invention may be used in the system of the second aspect of the invention, which differs in that the design of the emanator itself is different.
According to a fourth aspect of the invention there is provided a method of manufacturing an emanator according to the first aspect of the invention, the method comprising: providing two or more elongate wires; providing a first plurality of short fibres arranged to pass between at least two of the two or more elongate wires; providing one or more second fibres aligned with the two or more wires; and twisting the wires and second fibres to trap the first fibres therebetween so that they extend substantially perpendicularly thereto.
According to a fifth aspect of the invention there is provided a method of manufacturing an emanator of the invention, the method comprising: providing an emanator precursor comprising an elongate element having a first plurality of short fine fibres attached to a core and extending substantially perpendicular thereto; and wrapping one or more second fibres tightly in a helical pattern along the core.
The method may further comprise deforming at least some of the first plurality of fibres with the one or more second fibres, so that the deformed first fibres extend substantially along the direction of the core.
In an embodiment, the method of the fourth or fifth aspect may further comprise delivering the emanator, via a secondary rotatable member, to a primary rotatable member at an acute angle with respect to the axis of rotation thereof, the diameter of the primary rotatable member being greater than that of the secondary rotatable member. The primary rotatable member, which may be a cylinder or mandrel, may be the master or driver component, caused to rotate by a driving means e.g. a lathe. The secondary rotatable member, which may also be a cylinder or mandrel, may be a slave component that is free to rotate. The emanator may be delivered to the secondary cylinder under high tension. Preferably, the primary and secondary cylinders are positioned in close proximity to each other and such that their centres of rotation are aligned.
The method of either the fourth or fifth aspect of the invention may further comprise forming the emanator into one of: a spiral, a conical spiral, a square spiral, a helical coil, and Archimedean spiral. The spiral, conical spiral, square spiral, helical coil, or Archimedean spiral may be formed by altering the tension and/or said angle during the winding of the emanator onto said primary member.
The above described method is not constrained to forming emanators and so, according to a sixth aspect of the invention, a method of winding a metal strip or wire onto a primary rotatable member comprises delivering a metal strip or wire, via a secondary rotatable member, to a primary rotatable member at an acute angle with respect to the axis of rotation thereof, the diameter of the primary rotatable member being greater than that of the secondary rotatable member. The primary rotatable member, which may be a cylinder or mandrel, may be the master or driver component, caused to rotate by a driving means e.g. a lathe. The secondary rotatable member, which may also be a cylinder or mandrel, may be a slave component that is free to rotate. The wire or strip may be delivered to the secondary cylinder under high tension. Preferably, the primary and secondary cylinders are positioned in close proximity to each other and with their centres of rotation are aligned. The wire or strip may be formed into one of a spiral, conical spiral, square spiral, helical coil, or Archimedean spiral by altering the tension and/or said angle during the winding of the wire or strip onto said primary member.
Embodiments of the invention are described below, by way of example, with reference to the accompanying drawings in which:
a shows an emanator element of another embodiment of the present invention part way through construction;
a illustrates a method for forming a spiral emanator according to embodiments of the invention;
a shows the emanator of the embodiment of
Referring to
Referring to
An alternative way of making the emanator of the invention, which can result in a larger emanating surface area, is to lay second fibres in the form of the longitudinal threads 14 alongside the wires of the emanator prior to the wires being twisted to trap the fibres. In this way the threads 14 are maintained centrally in the emanator without the reduction in the number of short fibres 12. The threads 14 are twisted together with the wires and form a central flow path, which as discussed above may be a capillary flow path, along the axis of the emanator. The lower half of
As this method results in the flow path formed by the second fibres 14 being totally surrounded by the first plurality of fibres this will reduce direct evaporation from the thread 14 which will result in an ever greater improvement of fluid flow along the emanator. The number of threads (or “core yarns”) 14 provided can be varied to provide high or low output devices as required. For example, one or two core yarns 14 could be utilised for a low output device; three, four, five, six, seven, eight, nine, ten or more threads 14 could be utilized where the output is required to be greater.
Twisting the support wires physically separates the first (emanating) fibres 12 into ‘tufts’ 12a. The core yarns 14 are in contact with the radial emanating fibres 12 as a result of being trapped between the wires during construction. This provides a continuous capillary circuit from one end of the emanator to the other A pathway is created for a fluid to travel along by being influenced by the forces of gravity to act on separate opposing columns of the circuit to control the supply of liquid to the emanator.
The spacing created between adjacent tufts of the radial emanating fibres 12 is particularly useful in providing an emanating system that is highly permeable to air, which is useful for efficiently evaporate the fluid, and the density of the emanating fibres 12 is thus chosen accordingly to maximise the amount of exposed surfaces for efficient evaporation of the liquid product. I.e. it is desirable not to pack the fibres 12 too densely as this would decrease the emanator's permeability to air.
The emanator may be formed into any convenient shape which maximises the length of the emanator whilst minimising its volume, or space envelope. Referring to
Embodiments of the invention thus provide constant delivery of fluid through the provision of a multi-coiled emanator having a long path length to provide enough time for evaporation. The spiral path provides continuous ‘irrigation’ to maintain high performance of the product.
In the emanator there are three system effects that interact with one another, those being the rate of flow of the material, the rate of evaporation of the material and the temperature. For an efficient system there needs to be a balance of these factors that can cope with temperature fluctuations, and the shape of the coil can assist in providing a stable system, that is one with reliable and repeatable evaporation characteristics. Any section of the length of the coil represents a certain surface area available for evaporation. The liquid flows down the coil from the top to the bottom and at lower temperatures the liquid product travels further down the spiral and is therefore evaporated over a longer length of the emanator. This provides a degree of temperature compensation by making a larger surface area available at lower temperatures to enable a more consistent evaporation rate therefrom. Conversely, at higher temperatures the fluid may fully evaporate before it reaches the end of the emanator.
As discussed above, an emanator in the form of a conical spiral has several advantages. A method of forming such an emanator will now be described, with reference to
The secondary cylinder 15b is of much smaller diameter, and is free to rotate about its axis (indicated by the crosshairs at c2). The emanator is delivered to the forming system 15a, 15b under high tension (i.e. the tension force acts in a direction t away from the forming system 15a, 15b). The primary and secondary cylinders 15a, 15b are positioned in close proximity to each other, i.e. with only a small gap approximately the size of the emanator therebetween, and such that their centres of rotation, c1 and c2 respectively, are aligned with an axis X-X (shown horizontally in
The secondary cylinder 15b, having a diameter much less than that of the primary cylinder 15a, produces a small diameter curve for the emanator being fed to the primary cylinder 15a. This small curve is opposite to the curve being formed on the large cylinder and, as such, has a greater structural strength that the larger curve of the primary cylinder and therefore exerts a greater force on the wires 13 of the emanator.
During the winding of the emanator on to the primary cylinder 15a, the coils thus produced can be wound onto the cylinder 15a so as to be spaced from each other along the length of the cylinder 15a, in order to produce a spiral of the desired length. This can be achieved by drawing the emanator along the length of the cylinders 15a, 15b during the winding process, and the cylinders 15a, 15b are of an appropriate length to accommodate the spiral windings.
In one embodiment, a larger cylinder 15a having a diameter of 30 mm and a smaller cylinder 15b having a diameter of 8 mm produced a spiral having a mean diameter of approximately 50 mm. It will, however, be appreciated that cylinders of other sizes e.g. a large cylinder having a diameter in the range substantially between 20-40 mm, or 25-35 mm, and a small cylinder having a diameter substantially in the range 4-12 mm, or 6-10 mm, could be used. In this embodiment, the delivery angle α was approximately 35°. Again, it will be appreciated that the angle can be altered to suit requirements, e.g. with the angle being substantially between 25 and 40° with respect to the horizontal. In any event, the resultant diameter produced is always greater than the diameter of the cylinder on which it is wound.
For a given tension, the size of the spiral being formed by this method is dependent upon the angle α. For example, the greater the angle α to the horizontal, the smaller the resultant mean diameter of the spiral produced; conversely, the smaller the angle α, the greater the mean diameter of the resultant coil. Therefore, a conical coil can be produced by winding the emanator onto the primary cylinder 15a, progressively changing the angle α between the start and finish thereof. Alternatively, the angle α can be kept constant, and the applied tension varied to produce a similar effect: a higher tension would result in a smaller mean diameter of the coils, and vice versa.
Providing the wires 13 of the emanator at the acute angle α (relative to the axis of the cylinders 15a 15b) to a smaller cylinder prior to winding around a larger cylinder has been found to be a convenient way to form the desired conical spiral shape for the emanator, and especially when using stainless steel wires 13. Using stainless steel advantageously avoids the problem of oxidization/corrosion mentioned above, although it was found to be difficult to form stainless steel into the desired configuration using conventional methods.
The method described with reference to
In the embodiments discussed above, and as shown ion
Referring to
The reservoir 26 and fluid delivery system 28 are preferably the same as those disclosed in WO01/77004 the teachings of which are incorporated herein by reference, and in particular that described in relation to
The reservoir has a pressure regulating means in it that ensures that the pressure at the bottom of a wick element of the fluid delivery system, that delivers fluid from the bottom of the container to the start of the emanator, is maintained substantially constant independently of the height of fluid in the container. This is achieved by means of the upper end of the container being sealed and an air inlet into the container being provided adjacent or at the same level as the outlet. In this manner a negative pressure develops above the fluid in the upper sealed end of the container that balances and acts against the pressure created by the fluid head height above the air inlet. Essentially the fluid pressure at the outlet is therefore maintained substantially at atmospheric pressure. Further details about the system are found in the above mentioned patent.
The system 22 of the invention can also include an absorbent element 30 which acts as a sink at the lower end of the emanator. As the fluid passes down the emanators known in the art, if the components of the fluid flowing along the emanator, in particular those components having a slower evaporation rate, reach the end of the emanator without evaporating then prior art emanators can become blocked with these slower evaporating fluids. These start to back up in the emanator, in particular along the flow path transporting the volatile material, gradually reducing the length of emanator to which the flow path is capable of delivering new fluid. This can, over time, change the composition of the material being evaporated from the emanator resulting in unacceptable eminence quality. By providing this “sink” at the end of the emanator any excess material can be allowed to flow from the end of the emanator, thereby preventing the flow paths along the emanator becoming backed up. The rate at which fluid enters the sink is much less than the rate at which the sink can evaporate fluid. This enables the sink to collect and retain any residues and solids that would normally block the capillaries, whilst emanating the remaining fluid, so that all of the product can be released linearly over time.
NB. This is a dynamic fluid system of emanating fragrance material, with a constant flow of fluid entering the top of the emanator and exiting from the bottom of the emanator after evaporating most of the product. The small amount of fluid exiting the bottom of the emanator into the sink 30 is important for the irrigation of the fluid circuit to maintain a high performance.
It has been found that providing a sink in the form of a porous sheet material provides the necessary absorbency. The sink 30 shown in the example of
Referring to
Referring to
Referring to
Although the above embodiments all disclose emanators which have a vertical component to fluid flow therein, it is also anticipated that the emanators of the present invention could have only a horizontal flow path. For example the emanators could be as shown in
A further embodiment of the system of the invention is shown in
Referring to
This oscillation induced by the electromagnetic effect of the coil 52 creates relative motion between the emanator 24 and the air surrounding it thereby promoting evaporation therefrom. The pulsed electromagnetic field created in the coil 52 and core 50 requires only a minimal amount of energy.
It will be appreciated by the skilled person that although described as being in the base 48, providing the electromagnetic field produced acts on the emanator 24, the positioning of the coil 52 and core 50 are only dictated by packaging requirements and may be placed in any suitable position.
Referring to
Within the fabric is a plurality of tufts of polyester fibres 68 that are trapped in the fabric such that loose ends thereof extend substantially perpendicular to the support 62. As can be seen the fibres 68 are only retained at their lower end and are loose at their upper end and fan out slightly as they extend away from the support 62. In use the longitudinal polyester threads 64 act as a capillary fluid pathway along which the volatile material can travel along the emanator, and the fibres 68 extending from the support give a large surface area from which the volatile material can evaporate. The traverse threads 66 act to transport the volatile material from the outer longitudinal threads to the fibres 68.
The polymer support 62 is made of a heat softenable polymer and the polymer is softened and the woven fabric pressed into its surface so as to attach thereto. In this manner the top surface of the fabric is exposed. Although the threads 64, 66 could transport the volatile material using capillary action if they were completely encapsulated, having them exposed on the surface assists in the transfer from the woven fabric to the fibres 68 and also assists in the emanator drawing the volatile material into it as this may occur on the exposed top side of the fabric which presents a larger surface area than would be exposed by the end of the threads 64, 66 of the fabric were fully encapsulated.
The emanator may be provided with a self-adhesive backing strip 70 by which it can be conveniently attached to a surface if required. It will be appreciated that this feature is optional and it is not a requirement of the invention that the emanator is adhered to a surface.
Referring to
Referring to
The reservoir 74 and fluid delivery system 76 are preferably the same as those disclosed in WO01/77004 the teachings of which are incorporated herein by reference, and in particular that described in relation to
The emanator coils from the top 78 of the fluid delivery system down around the exterior of the reservoir 74. The emanator 60 may be pre formed into the desired coil shape by heating it to soften the polymer support, forming it into the required shape, and then cooling the polymer support so as to maintain its required shape. The emanator 60 may be attached only to the top 78 of the fluid delivery system 76 and be freely suspended therefrom, or, alternatively the emanator 60 may be adhered to the outside of the reservoir 74, for example by use of the self-adhesive strip 70. As will be appreciated, if the emanator 60 is adhered to the exterior of the reservoir 74 it would not be necessary to pre-form it into a coil shape prior to adhesion. As the fibres 68 of the present invention only extend in one direction from the support 62, and as when winding the spiral for the emanator the fibres will extend outwardly from the fabric, forming the emanator into a coil opens out the fibres of the tufts away from one another thereby exposing a large emanating surface area and at the same time increasing its permeability to air. This greatly improves the evaporation of volatile material from the emanator. Due to the improved ability of this design of emanator to evaporate volatile material, it is anticipated that the emanator length using this design can be reduced compared to the emanator design of
The top 78 of the fluid delivery system has a slot (not shown) formed therein into which the end of the emanator can be inserted such that fluid from the reservoir can contact the longitudinal fibres running along the emanator 60 so as to be transported therealong.
Referring now to
In addition the system 72A also comprises a fan 82 disposed above the reservoir 74 and emanator 60. The fan 82 is coupled to an electric motor (not shown) which is powered by a source of electricity, for example a battery or a supply of mains electricity. The fan rotates in a direction to draw a flow of air over the coil of emanator 60 in an upwards direction as depicted by the arrows.
As shown in
It will be appreciated that the system described herein with reference to
Tests were run on an emanator system of the invention. A reservoir, emanator and an evaporative sink as shown in
To make the emanator two craft pipe cleaners were joined together and placed in tension in a lathe and two lengths of polyester cotton were then tightly wound around the pipe cleaner in a helical fashion by rotating the pipe cleaner with the lathe and gradually moving the polyester cotton along its length as it rotated. Once made the emanator was formed into a helical shape and attached to a pressure compensated reservoir as detailed hereinabove. The reservoir contained Hoshi Hula 463182B fragrance produced by Firmenich. Although not necessary for the functioning of the emanator, it may, in some circumstances, be beneficial to clean the emanator element prior to use, preferably as part of the manufacturing process. Cleaning may, for example, remove any residue or coatings on the core of the emanator that could otherwise become dissolved in the volatile material as it passes along the emanator. Although it is not believed that this would affect the evaporation of fluid from the emanator, it may, for example, lead to discolouration which could provide an undesirable visual effect.
To test the invention the emanator, reservoir and evaporative sink were housed in a ventilated enclosure containing a fan. The fan was electronically controlled through a cyclic pattern of on/off with an off time of ninety seconds followed by an on time of sixty seconds.
Daily measurements of the mass of the system were taken and the weight loss, in grams per twenty four hour period, was calculated over a 22 day period. The system was run continuously day and night for the duration of the test and the temperature was uncontrolled and therefore variable. The weight was measured at substantially the same time each day by placing the system on a Satorious Universal Electronic Scale, and the readings recorded. Weight loss per 24 hour period was then calculated.
As can be seen although there is some day to day variation in the weight loss there is no overall trend and the weight loss due to emanation is substantially linear over time. The fluctuations, such as they exist, may be influenced by factors such as differing temperatures on a day to day basis.
The test was also repeated without utilizing a fan, and the daily measurements for a period of 28 days are shown below.
Again, although there is some day to day variation in the weight loss, and the weight loss due to emanation is substantially linear over time. The fluctuations, such as they exist, may be influenced by factors such as differing temperatures on a day to day basis. The average daily weight loss over this 28 day period is 0.31 g/24 hours, and the total fragrance released was 8.8 g.
It will be appreciated by the skilled person that the various features of the different embodiments described above may be used in combination with the features of different embodiments.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1214889.6 | Aug 2012 | GB | national |
| 1220407.9 | Nov 2012 | GB | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/GB2013/052203 | 8/21/2013 | WO | 00 |
