WO2011038171A1

WO2011038171A1 - Electro-hydrodynamic spray device

Info

Publication number: WO2011038171A1
Application number: PCT/US2010/050095
Authority: WO
Inventors: Beverly A. Piatt; James E. Dvorsky
Original assignee: Battelle Memorial Institute
Priority date: 2009-09-28
Filing date: 2010-09-24
Publication date: 2011-03-31
Also published as: WO2011038175A1; WO2011038171A4

Abstract

An electro-hydrodynamic (EHD) device is provided in combination with a bottle. The bottle comprises a container including a liquid formulation to be comminuted into a spray of droplets and a wick extending into the container. The wick has an end portion. The EHD device comprises a first conductive element at a first electrical potential. The EHD device further comprises a second conductive element at a second electrical potential. The first and second electrical potentials at the first and second conductive elements result in a strong electric field being generated in the vicinity of the first element end section. The bottle may be removably coupled to the EHD device.

Description

ELECTRO-HYDRODYNAMIC SPRAY DEVICE

TECHNICAL FIELD

The present invention relates an electro-hydrodynamic (EHD) spray device adapted to receive a commercially available refill bottle typically used in a plug-in electrical evaporator having a resistance heater.

BACKGROUND ART

U.S. Patent No. 7,341,698 discloses a plug-in electrical evaporator for dispersing chemical actives such as insecticides and fragrances. The evaporator comprises a multi-piece housing in which a bottle is detachably retained. The bottle contains an evaporable substance such as a liquid formulation including an insecticide, fragrance, odor eliminator or the like. A wick extends from the bottle through which the liquid formulation is drawn. A cap is associated with the bottle and comprises a sheath for receiving the wick. A lower portion of the wick is immersed in the liquid formulation, and an upper portion of the wick protrudes above the bottle. The evaporator further comprises a heater provided in the housing for heating the wick to enhance the rate at which the liquid formulation evaporates into the surrounding environment. Once all of the liquid formulation has been removed from the bottle, a suitable refill is available. For example, the '698 patent teaches that suitable refill bottles are available from S.C. Johnson & Son under the GLADE®, PLUGINS® AND RAID® brand names.

DISCLOSURE OF INVENTION

In accordance with a first aspect of the present invention, an electro-hydrodynamic (EHD) device is provided in combination with a bottle. The bottle comprises a container including a liquid formulation to be comminuted into a spray of droplets and a wick extending into the container. The wick has an end portion. The EHD device comprises a first conductive element including an end section defining an EHD comminution site. The first conductive element is at a first electrical potential and contacts and interfaces with the wick end portion. The EHD device further comprises a second conductive element at a second electrical potential. The first and second electrical potentials at the first and second conductive elements result in a strong electric field being generated in the vicinity of the first element end section. The bottle may be removably coupled to the EHD device. The first conductive element may be formed from a high surface energy, electrically conductive material such that liquid formulation moves from the wick end portion to an end section of the first conductive element defining the EHD comminution site.

The first conductive element may comprise a plurality of end sections defining a plurality of EHD comminution sites.

The first conductive element may comprise a cylinder-shaped element into which the wick end portion is positioned. The cylinder-shaped element may have at least one end section defining at least one EHD comminution site.

The first conductive element may comprise a crown-shaped element into which the wick end portion is positioned. The crown-shaped element may have a plurality of end sections defining a plurality of EHD comminution sites.

The first conductive element may comprise a plurality of capillary tubes formed from a high surface energy, electrically conductive material. The capillary tubes may have end sections defining a plurality of EHD comminution sites.

The EHD device may further comprise a dielectric shroud positioned between the first and second conductive elements

The second conductive element may be located between the container and the first conductive element and generate a cloud of ions that forms a virtual electrode cloud near the first element end section.

In accordance with a second aspect of the present invention, a process is provided for generating a spray of droplets from a liquid formulation using an electro-hydrodynamic (EHD) device in combination with a bottle. The process comprises: providing a removable bottle comprising a container including a liquid formulation to be comminuted into a spray of droplets and a wick extending into the container. The wick may have an outer portion such that liquid formulation is conveyed along the wick to the wick outer portion via capillary action. The process may further comprise providing an EHD device comprising first and second conductive elements; assemblying the bottle with the EHD device such that the bottle wick outer portion is positioned near the first conductive element; and creating a strong electric field in the vicinity of at least one of the wick outer portion and the first conductive element by applying a first electrical potential to the first conductive element and a second electrical potential to the second conductive elements so as to generate a spray of liquid formulation droplets. The first conductive element may comprise a cylinder-shaped first conductive element. The positioning step may comprise positioning the bottle wick outer portion within the cylinder-shaped first conductive element.

The second electrode may be positioned away from the first electrode such that the second electrode generates a cloud of ions that forms a virtual electrode cloud near at least one of the wick outer portion and the first conductive element.

The process may further comprise replacing the bottle when empty with a refill bottle.

In accordance with a third aspect of the present invention, an electro-hydrodynamic (EHD) device is provided comprising a housing having first and second sections and bottle- locating structure coupled to the first section. The bottle-locating structure is capable of receiving and securing a first bottle comprising a container having a first geometry to the first section. In place of the first bottle, the bottle-location structure is also capable of receiving and securing a second bottle comprising a container having a second geometry different from the first geometry to the first section. The EHD device further comprises an EHD control circuit associated with the housing.

The bottle-locating structure may comprise one or more movable locator lugs.

In accordance with a fourth aspect of the present invention, an electro-hydrodynamic (EHD) device is provided in combination with a bottle. The bottle may comprise a container including a liquid formulation to be comminuted into a spray of droplets and a wick extending into the container. The wick may have an outer portion. The EHD device may comprise a first conductive element including an end section engaging and shaping the bottle wick outer portion to define two or more parts comprising EHD comminution sites. The first element may be at a first electrical potential. The second conductive element may be at a second electrical potential. The first and second electrical potentials at the first and second conductive elements results in a strong electric field being generated in the vicinity of the bottle wick outer portion.

The first conductive element may comprise a cutting element for cutting the bottle wick end portion into the two or more parts, each defining an EHD comminution site.

The first conductive element may comprise a die for receiving and forming the bottle wick end portion into the two or more parts, each defining an EHD comminution site. BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 is a perspective view of an electro-hydrodynamic (EHD) spray device constructed in accordance with a first embodiment of the present invention;

Fig. 2 is a perspective view of the spray device in Fig. 1 in a closed state;

Fig. 3 is a side view of the spray device in Fig. 1 in a partially open state with a portion of a side wall removed;

Fig. 4 is a side view of the spray device in Fig. 1 in a closed state with a portion of a side wall removed;

Fig. 5 is a view of a portion of a wick upper portion including a dotted line showing where the wick upper portion may be cut to form a beveled tip;

Fig. 6 is a view similar to Fig. 5 illustrating the wick upper portion cut to include a beveled tip;

Fig. 7 illustrates control circuitry forming part of the spray device illustrated in Fig. 1; Figs. 8 and 8A-8C illustrate an EHD spray device including a slideable cutting element;

Figs. 9A-9D illustrate an EHD spray device including a cutting element mounted within the housing;

Figs. 1 OA- IOC illustrate locator lugs capable of receiving and securing bottles having different geometries;

Figs. 11 and 11 A-l IB illustrate an EHD spray device including a permanent wick element;

Figs. 12 and 12A-12D illustrate an EHD spray device including a permanent wick element having a plurality of second sections each allowing for the formation of a Taylor cone;

Figs. 12E and 12F illustrate an EHD spray device including a permanent wick element including a plurality of capillary channels;

Figs. 13A-13B illustrate an EHD spray device including a crown-shaped electrically conductive element and a dielectric shield;

Fig. 14 illustrates control circuitry forming part of the spray device illustrated in Figs. 13A-13B;

Fig. 15 is a perspective view of an EHD spray device including a main housing having a conical upper portion and including a crown-shaped electrically conductive element; Fig. 16 is a perspective view of an EHD spray device including a main housing having a conical upper portion and including a plurality of electrically conductive capillary tubes;

Fig. 17 is a perspective view of an EHD spray device including a main housing having a conical upper portion and including a permanent wick element and a wick holder having a plurality of tube portions;

18 is a perspective view of an EHD spray device including a main housing having a conical upper portion and including a permanent wick element; and

19 is a perspective view of an EHD spray device including a main housing having a conical upper portion and including a cutting element for separating a wick into a plurality of wick sections each of which defines an EHD comminution site.

MODES FOR CARRYING OUT THE INVENTION

In accordance with a first embodiment of the present invention, an electro- hydrodynamic (EHD) spray device 10 is provided and adapted to receive a bottle, such as a commercially available refill bottle 100, see Fig. 1, which refill bottle 100 is typically used in a plug-in electrical evaporator having a resistance heater. It is believed that by dispensing the liquid formulation from the refill bottle 100 using the EHD spray device 10, rather than an electrical evaporator having a resistance heater, improved delivery of the liquid formulation is effected. Further, because the liquid formulation is not heated by a resistance heater, it is believed that the original scent or fragrance of the liquid formulation, when the liquid formulation comprises an aromatic oil, is preserved and not degraded and controllably delivered.

The bottle 100 comprises a container 102 having a main body portion 102A filled with an evaporable substance such as a liquid formulation comprising an aromatic oil, an insecticide, or the like. The bottle 100 further comprises a cap 106, which may include a threaded section (not shown) and an intermediate section 106A. The intermediate section 106A is integral with and extends from the threaded section. The threaded section is threadedly received in an opening of a neck portion 102B of the container 102. The container neck portion 102B is integral with the container main body portion 102A. The cap 106 further comprises a sleeve section 106B integral with the intermediate section 106A. The container 102 and the cap 106 may be made from an electrically insulative polymeric material. The bottle 100 further comprises a wick 108, which extends through the cap sleeve section 106B, the cap intermediate section 106A and the cap threaded section into the container main body portion 102A, where a lower portion (not shown) of the wick 108 is immersed in the liquid formulation. An upper portion 108 A of the wick 108 extends out from the cap sleeve section 106B, see Fig. 1. However, it is contemplated that the cap sleeve section 106B may extend to an end of the wick upper portion 108 A. The liquid formulation is drawn via capillary action from the container main body portion 102A up through an intermediate portion (not shown) of the wick 108 to the exposed wick upper portion 108 A. The wick 108 may be made from any of a variety of porous or fibrous materials, e.g., packed fibers, open cell foam, and the like, that provide a liquid pathway from one end of the wick 108 to the other end. The porous or fibrous material may effect movement of the liquid formulation through the wick 108 via capillary action.

Preferably, the wick upper portion 108 A has a tip 108B, also referred to herein as an EHD comminution site, that is beveled, cone-shaped or has any another shape that allows for the formation of a Taylor cone at the tip 108B. The Taylor cone is generated by a strong electrical field created by a control circuitry 30, discussed below, at the wick tip 108B, such that the liquid formulation forms a jet or ligament at the tip 108B which separates, or comminutes, into an aerosol. In Fig. 5, a dotted line L is shown where the wick upper portion 108A may be cut so as to form a beveled tip 108B, as shown in Fig. 6.

Commercially available refill bottles 100 often comprise wicks 108 having a right cylinder geometry, that is, the upper portion has a tip or end surface that is flat and at a right angle to the cylindrical side of the wick 108. The wick upper portion 108 A may be shaped or cut such that it has a tip 108B that is beveled, cone-shaped, serrated or has any other shape that provides a preferential location for the Taylor cone to form when comminuting the liquid formulation via the EHD process. In a first embodiment, the bevel shape illustrated in Fig. 6 may be accomplished by manually cutting the wick upper portion 108 A with scissors or a knife along dotted line L in Fig. 5. If the cap sleeve section 106B extends to the end of the wick upper portion 108 A, then a corresponding portion of the cap sleeve section 106B is cut along with a part of the wick upper portion 108A.

The electro-hydrodynamic (EHD) spray device 10 comprises the clam-shell housing

20 having lower and upper sections 22 and 24 pivotally coupled to one another. The lower section 22 comprises a main body 124 having an internal cavity (not shown) for housing the control circuitry 30, see Fig. 7, for the spray device 10. Locator lugs 24B extend from a top surface 24A of the main body 124, see Figs. 1 and 3, for locating and securing, such as via a friction fit, the bottle 100 to the lower section main body 124. Also extending from the main body top surface 24A is a first housing extension 25 (shown in cross section in Figs. 3 and 4), which, in the illustrated embodiment, is integral with the main body 124. An electrically conductive pin 26, having a sharp tip in the illustrated embodiment, extends through and out from a curved top end 25 A of the first extension 25, see Figs. 3 and 4. First and second electrically conductive posts 27A and 27B extend through and out from the main body top surface 24A, see Figs. 1, 3 and 4. The pin 26 and first and second posts 27A and 27B form part of the control circuitry 30, as will be discussed below.

The upper section 24 of the housing 20 comprises a recessed cover 24A and a second housing extension 125 extending down from the cover 24A, see Fig. 3. The second extension 125 has a curved end 125 A, see Figs. 1 and 3. An aperture 124 A is provided in the cover 24A, see Fig. 2. Comminuted liquid formulation exits the housing 20 through the aperture 124 A.

The clam-shell housing 20 illustrated in Fig. 1 encases the entire bottle 100, including the entire container 102 and the wick 108. It is contemplated that a spray device of the present invention may comprise a housing that encases only a portion of the bottle 100. For example, the housing of the EHD spray device may enclose only a portion of the container 102. It is also contemplated that the EHD spray device housing may have a configuration or design that complements that shape of the bottle 100, yet only encases a portion of the bottle 100.

It is further contemplated that an EHD spray device housing, such as the clam-shell housing 20 illustrated in Fig. 1, may include a clear window incorporated therein so as to allow a user to visually see at least a portion of the bottle 100, such as the container 102, to determine an amount of liquid formulation remaining in the container 102. Once all of the liquid formulation has been depleted from the container 102, the container 102 can be removed from the housing 20 and a new refill bottle 100 inserted in its place.

The control circuitry 30 comprises a high voltage generator 32 powered by a battery 34 having its positive terminal coupled to the high voltage generator 32 via a switching circuit (SW) 36, see Fig. 7. The high voltage generator 32 acts to multiply the voltage supplied by the battery 34 to provide a voltage sufficient to generate an electric field required to achieve comminution of liquid issuing from the exposed wick upper portion 108 A. The conductive pin 26 is connected to the negative terminal of the high voltage generator 32, while the conductive posts 27A and 27B are connected via a resistance R to the high voltage or positive terminal of the high voltage generator 32. The switching circuitry 36 may consist of a simple mechanical switch such as a push or rocker button manually updated by a user or may consist of an electrically activated switch such as a relay or an electronic switch. When the switching circuitry 36 is operated to activate the high voltage generator 32, the voltage between the electrically conductive pin 26 and the posts 27A and 27B creates a strong electrical field in the vicinity of the wick tip 108B or EHD comminution site causing charge to be induced in the liquid within the wick tip 108B. As is known in the art, this causes the liquid surface tension to break down such that an electrically charged dispersion of droplets, substantially all of the same size (a "monodispersion"), is formed. Hence, the liquid is broken up, or comminuted, into a spray of fine aerosol droplets. In doing so, droplet size and droplet size distribution may be closely controlled. Droplet size may be in the sub-micron range, thus enabling rapid vaporization of the aromatics causing a rapid onset of a perceived fragrance and without denaturing.

The control circuitry 30 may be constructed as described in U.S. Patent Application

Publication No. 2006/0261179, which is incorporated herein by reference in its entirety.

It is also contemplated that the polarity of the control circuitry 30 may be reversed such that the pin 26 is coupled to the positive terminal of the high voltage generator 32 and the posts 27A and 27B are coupled to the negative terminal of the high voltage generator 32.

It is still further contemplated that the pins 27A and 27B may have sharp tips or blunt tips. When the pins 27A and 27B are provided with sharp tips, it is believed that they generate ions that bombard the emitted droplets so as to discharge the droplets. This is advantageous if the intent is to have the emitted droplets linger in the surrounding air and not adhere to furniture, a person's skin or the like. Alternatively, it is believed that if the pins 27A and 27B are provided with blunt tips, the emitted particles will not be bombarded with ions, but instead, will remain charged. This is advantageous if the intent is to have the emitted droplets adhere or attract to a person's skin or clothing or other desired object or article.

In operation, a bottle 100 is placed onto the top surface 24 A of the main body 124 so as to be positioned between the lugs 24B. Further, the cap sleeve section 106B is positioned over the conductive pin 26 extending out from the first housing extension 25. Initially, as shown in Fig 3, the conductive pin 26 does not extend through the wick 108 or the cap sleeve section 106B. After the bottle 100 is positioned as shown in Fig. 3, an operator closes the housing 20 by moving the upper section 24 towards the lower section 22 such that the second housing extension 125 engages the cap sleeve section 106B and applies a force to push the sleeve section 106B down onto the conductive pin 26, i.e., the pin 26 pierces through the cap sleeve section 106B and the wick 108, such that the pin 106B is positioned approximately mid-way through the width of the wick 108 as illustrated in Fig. 4.

Liquid formulation flows from the container 102 through the wick 108 to the wick beveled tip 108B via capillary action. The rate of capillary delivery should be sufficient to at least match the rate of EHD comminution or the EHD comminution site will be starved of liquid and aerosolization will cease, or, at a minimum, aerosolization oscillates as liquid partially replenishes the EHD comminution site and is sprayed away, or aerosolization is throttled to a rate determined by the rate of capillary delivery. It is also contemplated that the wick 108 may be sized so as to provide a desired flow rate to the EHD comminution site generally matching the rate of EHD comminution.

As noted above, when the switching circuitry 36 is operated to activate the high voltage generator 32, the voltage between the electrically conductive pin 26 and the posts 27A and 27B creates a strong electrical field in the vicinity of the wick tip 108B or EHD comminution site causing charge to be induced in the liquid within the wick tip 108B. This causes an electrically charged dispersion of droplets, which exit the housing 20 via the aperture 124 A.

The wick upper portion 108 A may be cut or shaped via a cutting element incorporated into the housing 20 of the spray device 10. In one embodiment, a cutting element is located in the housing upper section 24 near the second extension 125. The bottle 100 is placed on the top surface 24 A of the main body 124 so as to be positioned between the lugs 24B. When the housing upper section 24 is moved so as to close onto the lower section 22, the cutting element in the upper section 24 is forced into and through the wick upper portion 108 A so as to shape the upper portion to form, for example, the beveled tip 108B illustrated in Fig. 6. The removed wick part may fall into a holding well formed within the lower section 22 of the housing 20 so that it does not interfere with the EHD comminution process.

In a further alternative embodiment, a slideable cutting element is located in either the lower section 22 or upper section 24 of the housing 20. In the embodiment illustrated in Figs. 8, 8A-8C, where elements common to the embodiment of Figs. 1-4 and the embodiment of Figs. 8, 8A-8C are referenced by the same reference numerals, a slideable cutting element 210 is located in an upper section 224 of a housing 200 of an EHD spray device. A guide slot 224A is provided in the housing upper section 224, see Figs. 8, 8A and 8B. The cutting element 210 comprises a blade 21 OA and a gripping portion 21 OB, see Fig. 8C. When the housing upper section 224 is closed onto its corresponding housing lower section 222, the blade 21 OA is positioned within the housing 200. The blade 21 OA is capable of traversing along a path so as to cut a wick upper portion 108 A, when a bottle 100 is mounted within the housing 200. The guide slot 224 A is preferably located at an angle Θ224Α to a longitudinal axis A108 to the wick 108, wherein the angle Θ₂₂₄Α is preferably between about 30 degrees and 60 degrees, see Fig. 8 A. The gripping portion 210B is accessible by a user from outside of the housing upper section 224 so as to move the cutting element 210 along the path, see Figs. 8, 8A and 8B.

To cut a wick upper portion 108 A, a bottle 100 is placed on the top surface of a main body 124 of the housing lower section 222 so as to be positioned between locator lugs . The housing upper section 224 is then moved so as to close onto the lower section 222. After the housing upper section 224 engages with the lower section 222 and prior to actuating the control circuitry 30, the slideable cutting element 210 is manually moved from its home position, illustrated in Fig. 8A, in the direction of arrow 212, across the wick upper portion 108 A so as to cut or shape the wick upper portion 108 A to form, for example, the beveled tip 108B illustrated in Fig. 6. After the cut has been made, the cutting element 210 may be returned to its home position. Also after the cutting operation, the removed wick part is preferably stored away from the wick 108 and the pin 26 and posts 27A and 27B so as not to interfere with the EHD comminution process. In the embodiment illustrated in Figs. 8, and 8A-8C, a corresponding portion of the cap sleeve section 106B is cut together with the wick upper portion 108 A.

In another embodiment, a cutting element, such as a cutting blade, is mounted within the housing 20 at a convenient location that does not interfere with normal device operation. For example, the blade may be positioned in the housing lower section 22 or the housing upper section 24 at a location opposite the first extension 25 and the second extension 125. Features in the housing 20 and surrounding the blade locate the wick upper portion 108 A relative to the blade. To cut or shape the wick upper portion 108 A, the wick is located relative to the cutting element by the housing features. Then, the housing upper section 24 is moved so as to close onto the lower section 22 causing the cutting element to cut or shape the wick upper portion 108 A so as to shape the upper portion to form, for example, the beveled tip 108B illustrated in Fig. 6. The housing 20 is subsequently opened, the wick is removed from the locating features in the housing 20 and then the bottle 100 is placed on the top surface 24 A of the main body 124 so as to be positioned between the lugs 24B. The housing upper section 24 is again moved so as to close onto the lower section 22 so as to cause the pin 26 to pierce through the cap sleeve section 106B and the wick 108, as discussed above.

An example of an embodiment where the closing of a housing upper section effects the cutting of a wick upper portion is illustrated in Figs. 9A-9D. In this embodiment, a cutting element 310 is mounted within a lower section 322 of a clam-shell housing 302 of an EHD spray device 300. The housing lower section 322 comprises a wall 322A having first and second slots 322B and 322C through which the cutting element 310 may extend. In the illustrated embodiment, the cutting element 310 comprises a blade portion 31 OA, first and second stops 310B and 3 IOC and an upper portion 310D positioned between the first and second stops 310B and 3 IOC. A spring 31 1 (not shown in Figs. 9B and 9C) is positioned about the upper portion 310D and engages the first stop 310B and an upper surface 322D of the housing lower section wall 322A, see Fig. 9D. The spring 311 biases the cutting element 310 upward in Figs. 9A-9D to a non-cutting position. When the cutting element 310 is located in its non-cutting position, the second stop 3 IOC engages the housing lower section wall 322A.

A wick-receiving slot 323 is provided in the housing lower section 322, i.e., features or walls of the housing lower section 322 define the slot 323. The slot 323 is dimensioned so as to be slightly larger but similar in shape to the wick upper portion 108 A and its corresponding portion of the cap sleeve section 106B. The slot 323 is also angled relative to the cutting element 310, see Figs. 9A-9C. To cut the wick upper portion 108A so as to provide it with a beveled shape, the wick upper portion 108 A is inserted into the slot 323. An upper section 324 of the housing 302 is manually moved towards its corresponding lower section 322 of the housing 302, see Fig. 9A. As the upper section 324 nears the lower section 322, a front edge 324A of the upper section 324 engages and forces down the cutting element 310 such that the cutting element 310 cuts or shapes the wick upper portion 108 A to form the beveled tip 108B illustrated in Figs. 6 and 9C. Because the slot 323 is angled relative to the cutting element 310, the wick upper portion 108A is cut at an angle θ₁₀₈, preferably between about 30 degrees and 60 degrees, see Fig. 9C. When the housing 300 is opened, the cut wick part can be removed from the slot 323 by an operator.

It is contemplated that the locator lugs (also referred to herein as bottle locating structure) may be movable relative to the top surface 24A of the housing lower section main body 124, for receiving, locating and securing, such as via a friction fit, one of a plurality of bottles having different geometries. In Figs. 1 OA- IOC, each locator lug 400 comprises a fixed base element 402 and a movable gripping element 404 coupled to and movable relative to its base element 402. A spring 406 is provided between the base element 402 and the movable gripping element 404 to bias the gripping element 404 in a direction away from its base element 402.

In Fig. 10A, the bottle 100 comprises a container 102 having a width W102 greater than a height H₁₀₂. The gripping elements 404 extend away from their corresponding base elements 402 a sufficient distance so as to grip the container 102 and secure the container 102 in position relative to the top surface 24A of the housing lower section main body 124. In Fig. 10B, the bottle 500 comprises a container 502 having a width W502 less than a height H502. The gripping elements 404 extend away from their corresponding base elements 402 a sufficient distance so as to grip the container 502 and secure the container 502 in position relative to the top surface 24A of the housing lower section main body 124. In Fig. IOC, the bottle 510 comprises a container 512 having a bulbous shape. The gripping elements 404 extend away from their corresponding base elements 402 a sufficient distance so as to grip the container 512 and secure the container 512 in position relative to the top surface 24 A of the housing lower section main body 124.

In a still further embodiment of the present invention, illustrated in Figs. 11, 11A and 1 IB, where elements common to the embodiment of Figs. 1-4 and the embodiment of Figs. 11, 11A and 1 IB are referenced by the same reference numerals, an EHD spray device 600 is provided having a clam-shell housing 620 similar to housing 20 illustrated in Fig. 1. The device 600 further comprises a permanent wick element 630 mounted within the housing 620. The housing 620 comprises lower and upper sections 622 and 624 pivotally coupled to one another. The lower section 622 comprises a main body 623 having an internal cavity (not shown) for housing control circuitry 30, see Fig. 7, for the spray device 600. Extending from a top surface 623A of the main body 623 is a wick holder 632, see Figs. 11 A and 1 IB. A bore 632A is provided in the wick holder 632. The permanent wick element 630 extends part-way through the bore 632A. The wick element 630 is fixed to the wick holder 632. A first end portion 630A of the permanent wick element 630, in the illustrated embodiment, has a right cylinder shape with a generally flat outer surface 630B. A second end portion 630C of the permanent wick element 630 has generally conical shape with a tip 630D to allow for the formation of a Taylor cone. It is further contemplated that the permanent wick second end portion 630C may be beveled or have any other shape so as to allow for the formation of a Taylor cone.

The permanent wick element 630 may be constructed from packed fibers or open cell foam. Preferably, the permanent wick element 630 is formed from a material which is chemically compatible with the liquid formulation to be delivered. It is also contemplated that the permanent wick element 630 may comprise one or more capillary channels defined in the wick holder 632, wherein the wick holder 632 may be formed from a polymeric material, which may be conductive or non-conductive.

When a bottle 100 is located within the housing 620 and moved in the direction of arrow 640 in Fig. 11 A, a tip 108B of the upper portion 108A of the wick 108 forming part of the bottle 100 is inserted into the wick holder bore 632A so as to abut against or otherwise mate with the first end portion 63 OA of the permanent wick element 630. In this

embodiment, the wick upper portion 108A is not cut prior to use. Hence, the wick upper portion 108 A has a right cylinder shape with its tip 108B defining a generally flat outer surface. Liquid formulation flows from the container 102, through the wick 108 and then through the permanent wick element 630 to the second end portion tip 630D, which defines an EHD comminution site. As noted above, the tip of the second end portion 630C of the permanent wick element is cone-shaped, but may be beveled, or may have any another shape that allows for the formation of a Taylor cone. Hence, in this embodiment, the upper portion 108 A of the wick 108 forming part of the bottle 100 does not need to be cut or shaped prior to the EHD comminution process since the permanent wick element 630 already has a shape at its second end portion 630C to allow for the formation of a Taylor cone. Consequently, it is believed that inserting a bottle 100 in this spray device 600 will be easier for a user since the user is not be required to cut or shape the wick upper portion 108A before use of the device 600.

A conductive pin 26 extends through the permanent wick element 630, see Figs. 11 A and 1 IB. First and second electrically conductive posts 27 A and 27B are positioned near the conductive pin 26. The conductive pin 26 and posts 27 A and 27B form part of the control circuitry 30 illustrated in Fig. 7.

It is contemplated that the permanent wick element may have two or more second end portions having tips and, hence, two or more EHD comminution sites where two or more Taylor cones can be formed. A first embodiment with a permanent wick element having two or more second end portions is illustrated in Figs. 12 and 12A-12D, where an EHD spray device 700 is provided having a clam-shell housing 720 similar to the housing 20 illustrated in Fig. 1. The spray device 700 further comprises a permanent wick element 730 mounted in the housing 720. The housing 720 comprises lower and upper sections 722 and 724 pivotally coupled to one another. The lower section 722 comprises a main body 723 having an internal cavity (not shown) for housing control circuitry 30, see Fig. 7, for the spray device 700.

Extending from a top surface 723 A of the main body 723 is a wick holder 732, see Figs. 12A and 12C. A plurality of first bores 732A and an internal cavity 732B are provided in the wick holder 732, wherein the first bores 732A communicate with the internal cavity 732B.

The permanent wick element 730 comprises a first section 73 OA and a plurality of second sections 730B in contact with the first section 73 OA. In the illustrated embodiment, the first section 73 OA is formed from an open cell foam and the second sections 730B are formed from packed fibers, which are in contact with the open cell foam first section 73 OA. The open cell foam and the packed fibers are preferably formed from a material which is chemically compatible with the liquid formulation to be delivered. It is also contemplated that the first section 73 OA could be formed from packed fibers and the second sections 730B could be formed from an open cell foam. It is still further contemplated that the first and second sections 73 OA and 730B of the permanent wick element 730 can be formed from any other material capable of defining a pathway for liquid formulation to travel through the internal cavity 732B and the first bores 732A. The first section 730A is generally horizontal and is located in the wick holder internal cavity 732B, while the second sections 730B are generally vertical and located in corresponding ones of the wick holder first bores 732A. The second sections 730B, in the illustrated embodiment, extend at an angle, e.g., 90 degrees, to the first section 73 OA.

The permanent wick element 730 is secured to the wick holder 732. The first section 730A of the permanent wick element 730, in the illustrated embodiment, has a center portion with an exposed outer surface 73 IB, see Figs. 12A and 12B. Each second section 730B of the permanent wick element 730 has a generally conical shape with a tip 730D to allow for the formation of a corresponding Taylor cone. It is further contemplated that the permanent wick second sections 730B may be beveled or have any other shape so as to allow for the formation of a Taylor cone.

When a bottle 100 is located within the housing 720 and moved in the direction of arrow 740 in Figs. 12A and 12B, a tip 108B of the upper portion 108 A of the wick 108 forming part of the bottle 100 is inserted into the wick holder inner cavity 732B so as to abut against or otherwise mate with the first section 73 OA of the permanent wick element 730. In this embodiment, the wick upper portion 108 A is not cut prior to use. Hence, the wick upper portion 108 A has a right cylinder shape with its tip 108B defining a generally flat outer surface. Liquid formulation flows from the container 102, through the wick 108 and then through the permanent wick element 730 to the second section tips 730D, which define EHD comminution sites. As noted above, the tip 730D of each second section 730B of the permanent wick element 730 is cone-shaped, but may be beveled, or have any another shape that allows for the formation of a Taylor cone. Hence, in this embodiment, the upper portion 108 A of the wick 108 forming part of the bottle 100 does not need to be cut or shaped prior to the EHD comminution process since the tip 730D of each second section 730B of the permanent wick element 730 already has a shape to allow for the formation of a Taylor cone. It is noted that because the second sections 730B of the permanent wick element 730 extend vertically, aerosol droplets are sprayed vertically upward and exit the housing 720 via an aperture (not shown but similar to aperture 124 A in cover 24 A) in the housing upper section 724.

A conductive pin 26 extends into the permanent wick element 730, see Figs. 12A and 12C. First and second electrically conductive posts 27 A and 27B having sharp tips are positioned near the conductive pin 26. The conductive pin 26 and posts 27 A and 27B form part of the control circuitry 30 illustrated in Fig. 7. A dielectric plate 29 is positioned between the conductive pin 26 and the posts 27A and 27B so as to prevent ions generated by the posts 27 A and 27B from impeding formation of Taylor cones at the tips 730D.

In a still further embodiment of the present invention, illustrated in Figs. 12E-12F, where elements common to the embodiment of Figs. 12 and 12A-12D and the embodiment of Figs. 12E-12F are referenced by the same reference numerals, the wick holder 832 comprises a plurality of vertical extensions 833A each having a first bore 832A defined therein and a main body portion 833B having an internal cavity 832B defined therein, wherein the first bores 832 A communicate with the internal cavity 832B.

The permanent wick element 830 comprises a first section 830A formed from an open cell foam. However, the first section 830A could be formed from packed fibers or any other material capable of defining a pathway for liquid formulation to travel through the internal cavity 832B and the first bores 832A. Also forming part of the wick element 830 are capillary channels 1832A defined by the first bores 832A formed in the wick holder vertical extensions 833A. The permanent wick element first section 830A is secured to the wick holder 832. The first section 830A has a central portion with an exposed outer surface 83 IB, see Fig. 12E. The wick holder vertical extensions 833A each have a generally conical shape with a tip 833C to allow for the formation of a corresponding Taylor cone.

A tip 108B of the upper portion 108 A of the wick 108 forming part of the bottle 100 is inserted into the wick holder inner cavity 832B so as to abut against or otherwise mate with the first section 830A of the permanent wick element 830. Liquid formulation flows from the container 102, through the wick 108 and then through the permanent wick element first section 830A, through the capillary channels 1832A via capillary action to the vertical extension tips 833C, which define EHD comminution sites.

In yet another embodiment, illustrated in Figs. 13A and 13B, an EHD device 2000 is provided for use with a refill bottle 2100, which may be replaced. The bottle 2100 comprises a container 2102 having a main body portion 2102A filled with an evaporable substance such as a liquid formulation comprising an aromatic oil, an insecticide, or the like. The bottle 2100 further comprises a cap 2106, which may include a base section 2106A and a sleeve section 2106B integral with the base section 2106A. The base section 2106A is threaded on its outer surface and is threadedly received in an opening of a neck portion 2102B of the container 2102. The container neck portion 2102B is threaded on its outer surface. The neck portion 2102B is also integral with the container main body portion 2102A. The container 2102 and the cap 2106 may be made from an electrically insulative polymeric material.

The bottle 2100 further comprises a wick 2108, which extends through the cap sleeve section 2106B, the cap base section 2106A, and into the container main body portion 2102A, where a lower portion of the wick 2108 is immersed in the liquid formulation. An upper portion 2108 A of the wick 2108 extends out from the cap sleeve section 2106B, see Fig. 13 A. However, it is contemplated that the cap sleeve section 2106B may extend to an end of the wick upper portion 2108A. The wick upper portion 2108A has a tip 2108B.

The wick 2108 may be made from any of a variety of porous or fibrous materials, e.g., packed fibers, open cell foam, and the like, that provide a liquid pathway from one end of the wick 2108 to the other end. The porous or fibrous material may effect movement of the liquid formulation through the wick 2108 via capillary action. Hence, in the illustrated embodiment, the liquid formulation is drawn via capillary action from the container main body portion 2102A into the wick lower portion, through an intermediate portion of the wick 2108, to the exposed wick upper portion 2108A. The EHD device 2000 comprises a main housing 2010 having an inner bore 2012. A threaded first section 2014 of the main housing 2010 defines a first part of the inner bore 2012 and is adapted to receive the container neck portion 2102B, which, as noted above, is threaded on its outer surface. Hence, the bottle 2100 can be removably coupled to the EHD device 2000 by threading the container neck portion 2102B into the first section 2014 of the main housing 2010. When the liquid formulation is removed from the bottle 2100, the empty bottle can be easily removed and replaced with another refill bottle 2100.

The EHD device 2000 further comprises a crown-shaped first electrically conductive element 2002 having a cylinder-shaped main body 2002A and a plurality of pointed end sections 2002B, see Figs. 13A and 14. The first conductive element 2002 also has an inner bore 2002C into which the bottle wick upper portion 2108 A is positioned, as will be discussed below. The first conductive element 2002 is preferably formed from a high surface energy, electrically conductive or semiconductive material, such as a thin metal, e.g., copper, static dissipative ABS, or any other high surface energy, conductive or semiconductive polymeric material. Hence, the term "first conductive element" encompasses a first element formed from either a high surface energy, electrically conductive material or a high surface energy, electrically semiconductive material. The first conductive element 2002 is fixed to a mount 2016 of the main housing 2010, see Fig. 13 A. As will be discussed further below, the first conductive element 2002 comprises part of a control circuitry 2030.

The EHD device 2000 still further comprises a dielectric shield 2004, which, in the illustrated embodiment, is cylindrical in shape, see Figs. 13A and 13B. The shield 2004 surrounds the main housing mount 2016 and the first conductive element 2002. The dielectric shield 2004 may be formed from acetal or other highly insulative material.

The EHD device 2000 also comprises a second electrically conductive element 2006 including a cylinder-shaped main body 2006A and a plurality of pointed end sections 2006B, see Figs. 13A and 14. As is illustrated in Figs. 13A and 13B, the pointed end sections 2006B are axially located between the first conductive element end sections 2002B and the container 2102. The second conductive element 2006 surrounds at least a portion of the dielectric shield 2004, see Figs. 13A and 13B. The second conductive element 2006 is preferably formed from a conductive or semiconductive material, such as stainless steel or a conductive or semiconductive polymeric material, and is fixed to the main housing 2010, see Fig. 13 A. Hence, the term "second conductive element" encompasses a second element formed from either an electrically conductive or a semiconductive material. As will be discussed further below, the second conductive element 2006 comprises part of the control circuitry 2030.

The control circuitry 2030 may be housed within the main housing 2010. The circuitry 2030 comprises a high voltage generator 32 powered by a battery 34 having its positive terminal coupled to the high voltage generator 32 via a switching circuit (SW) 36, see Fig. 14. The high voltage generator 32 acts to multiply the voltage supplied by the battery 34 to provide a voltage sufficient to generate an electric field required to achieve comminution of the liquid formulation carried by the wick upper portion 2108 A. The first conductive element 2002 is connected to the negative terminal (a ground, common or reference potential terminal in the illustrated embodiment) of the high voltage generator 32, while the second conductive element 2006 is connected via a resistance R to the high voltage and positive terminal of the high voltage generator 32. The switching circuitry 36 may consist of a simple mechanical switch such as a push or rocker button manually updated by a user or may consist of an electrically activated switch such as a relay or an electronic switch.

Because the first conductive element 2002 is formed from a high surface energy material, liquid formulation travels from the bottle wick upper portion 2108 A, along an inner surface of the first conductive element main body 2002A to the first conductive element pointed end sections 2002B.

When the switching circuitry 36 is operated to activate the high voltage generator 32, a relatively high electric field is formed at the second conductive element pointed end sections 2006B causing air molecules surrounding the second element pointed end sections 2006B to be electrically ionized to form a cloud of positively charged ions. At least a portion of the positively charged ions move outwardly from the second conductive element pointed end sections 2006B, around the dielectric shield 2004 and form a virtual positive electrode cloud in front of the first conductive element pointed end sections 2002B. The virtual positive electrode cloud and the grounded or negatively charged first conductive element pointed end sections 2002B create a strong electrical field in the vicinity of the first conductive element pointed end sections 2002B. In this embodiment, each of the first conductive element pointed end sections 2002B defines an EHD comminution site. Hence, negative surface charge is induced via the electric field in the liquid at the first element end sections 2002B. This causes the liquid surface tension to break down such that an electrically charged dispersion of droplets, in this embodiment, negatively charged droplets, substantially all of the same size (a "monodispersion"), is formed. Hence, the liquid is broken up, or comminuted, into a spray of fine aerosol droplets. In doing so, droplet size and droplet size distribution may be closely controlled. Droplet size may be in the sub-micron range, thus enabling rapid vaporization of the aromatics causing a rapid onset of a perceived fragrance and without denaturing.

The cloud of positively charged ions also functions to interact with and neutralize the negatively charged droplets generated at the EHD comminution sites. This results in droplets that are electrically neutral and able to be dispersed in the air without substantial influence of electric fields.

As noted above, the second conductive element pointed end sections 2006B are axially located between the first conductive element end sections 2002B and the container 2102, i.e., the second element end sections 2006B are located behind the first element end sections 2002B. It is believed that this location is advantageous because charged aerosol droplets are unlikely to migrate toward the second conductive element 2006, despite the mutual electrical attraction between the negatively charged aerosol droplets comminuted from the pointed end sections 2002B and the positive polarity of the second conductive element 2006.

As also noted above, the dielectric shield 2004 is located between the first and second conductive elements 2002 and 2006. The dielectric shield 2004 prevents the ions generated by the second conductive element pointed end sections 2006B from impeding formation of Taylor cones at the first conductive element end sections 2002B. Further, due to the location of the shield 2004, very little if any of the droplets generated by the EHD comminution sites move toward and adhere to the second conductive element 2006.

It is also contemplated that the polarity of the control circuitry 2030 may be reversed from what is shown in Fig. 14 such that the second conductive element 2006 is coupled to the high voltage terminal of the high voltage generator 2032 having negative polarity and the first conductive element 2002 is coupled to the relatively positive grounded or common terminal of the high voltage generator 32. It is still further contemplated that the polarity of the control circuitry 30 may be reversed from what is shown in Fig. 14 such that the first conductive element 2002 is coupled to the positive, high voltage terminal of the high voltage generator 32 and the second conductive element 2006 is coupled to the negative terminal of the high voltage generator 32.

In operation, a bottle 2100 is threaded into the threaded first section 2014 of the main housing 2010. As the bottle 2100 is threaded into the main housing first section 2014, the wick upper portion 2108 A moves into the inner bore 2002C of the first conductive element 2002. In the illustrated embodiment, the first conductive element 2002 directly contacts the bottle wick upper portion 2108 A. Liquid formulation flows from the container 2102, through the wick 2108 to the wick upper portion 2108 A and then along the inner surface of the first conductive element main body 2002A to the first conductive element pointed end sections 2002B. The rate of capillary delivery should be sufficient to at least match the rate of EHD comminution or the EHD comminutions site will be starved of liquid and aerosolization will cease, or, at a minimum, aerosolization oscillates as liquid partially replenishes the EHD comminution sites and is sprayed away, or aerosolization is throttled to a rate determined by the rate of capillary delivery. It is also contemplated that the wick 2108 may be sized so as to provide a desired flow rate to the EHD comminution sites generally matching the rate of EHD comminution.

As noted above, when the switching circuitry 36 is operated to activate the high voltage generator 32, the grounded or low voltage at the first conductive element 2002 and the high voltage at the second conductive element 2006 results in a virtual positive electrode cloud and a strong electrical field being generated in the vicinity of the first conductive element pointed end sections 2002B, each of which defines an EHD comminution site, causing charge to be induced in the liquid at the first element end sections 2002B. This causes an electrically charged dispersion of droplets.

In a still further embodiment of the present invention, illustrated in Fig. 15, where elements common to the embodiments of Figs. 1-4 and 14 and the embodiment of Fig. 15 are referenced by the same reference numerals, an EHD spray device 3000 is provided having a main housing 3010 comprising a base portion 3012 and a conical upper portion 3014. A refill bottle 100 comprising a container 102, a cap 106 and a wick 108 are housed within the main housing 3010.

The EHD device 3000 further comprises a crown- shaped first electrically conductive element 3002 having a cylinder- shaped main body and a plurality of pointed end sections 3002B, see Fig. 15. The first conductive element 3002 also has an inner bore into which the bottle wick upper portion 108 A is positioned, as will be discussed below. The first conductive element 3002 is preferably formed from a high surface energy, conductive or semiconductive material, such as a thin metal, e.g., copper, a static dissipative ABS, or any other high surface energy, conductive or semiconductive polymeric material. Hence, the term "first conductive element" encompasses a first element formed from either a high surface energy, electrically conductive material or a high surface energy, electrically semiconductive material. The first conductive element 3002 is fixed in the conical upper portion 3014 via spokes, ribs or like structure (not shown), see Fig. 13 A.

The EHD device 3000 still further comprises a conical-shaped dielectric shield 3004, see Fig. 15. The shield 3004 surrounds the first conductive element 3002. The dielectric shield 3004 may be formed from acetal or other highly insulative material.

The EHD device 3000 also comprises a second electrically conductive element 3006 having pointed end sections 3006B. The second conductive element 3006 is coupled to a base 3004A of the shield 3004, see Fig. 15. Hence, the pointed end sections 3006B are axially located between the first conductive element end sections 3002B and the container 102. The second conductive element 3006 is preferably formed from a conductive or semiconductive material, such as stainless steel sheet metal or a conductive or

semiconductive polymeric material. Hence, the term "second conductive element" encompasses a second element formed from either an electrically conductive or a

semiconductive material.

The first and second conductive elements 3002 and 3006 comprise part of a control circuitry, wherein the control circuitry may comprise like components and operate in a like manner as the control circuitry 2030 illustrated in Fig. 14 with the first conductive element 2002 in Fig. 14 replaced by the first conductive element 3002 in Fig. 15 and the second conductive element 2006 in Fig. 14 replaced by the second conductive element 3006 in Fig. 15. The control circuitry may be housed within the main housing base portion 3012.

Because the first conductive element 3002 is formed from a high surface energy material, liquid formulation travels from the bottle wick upper portion 108 A, along an inner surface of the first conductive element main body to the first conductive element pointed end sections 3002B.

In operation, a bottle 100 is mounted within the main housing 3010 such that the wick upper portion 108A moves into the inner bore of the first conductive element 3002. In the illustrated embodiment, the first conductive element 3002 directly contacts the bottle wick upper portion 108 A. Liquid formulation flows from the container 102 through the wick 108 to the wick upper portion 108 A and then along the inner surface of the first conductive element main body to the first conductive element pointed end sections 3002B. When the switching circuitry 36 is operated to activate the high voltage generator 32, the grounded or low voltage at the first conductive element 3002 and the high voltage at the second conductive element 3006 results in a virtual positive electrode cloud and a strong electrical field being generated in the vicinity of the first conductive element pointed end sections 3002B, each of which defines an EHD comminution site, causing charge to be induced in the liquid at the first element end sections 3002B. This causes an electrically charged dispersion of droplets.

In a further embodiment of the present invention, illustrated in Fig. 16, where elements common to the embodiments of Figs. 14 and 15 and the embodiment of Fig. 16 are referenced by the same reference numerals, an EHD spray device 4000 is provided having a main housing 3010 comprising a base portion 3012 and a conical upper portion 3014. A refill bottle 100 comprising a container 102, a cap 106 and a wick 108 are housed within the main housing 3010. In place of the crown-shaped first electrically conductive element 3002 provided in the Fig. 15 embodiment, a plurality of electrically conductive capillary tubes 4002 are provided. The tubes 4002 are preferable formed from high surface energy, electrically conductive material. The tubes 4002 may be joined together as a unit and inserted into the bottle wick upper portion 108 A. The capillary tubes 4002 have ends 4002A that define EHD comminution sites.

During operation of the spray device 4000, liquid formulation flows from the container 102, through the wick 108, to the wick upper portion 108A and then through the capillary tubes 4002 to their ends 4002 A. When the switching circuitry 36 is operated to activate the high voltage generator 32, the grounded or low voltage at the tubes 4002 and the high voltage at the second conductive element 3006 results in a virtual positive electrode cloud and a strong electrical field being generated in the vicinity of the tube ends 4002A, each of which defines an EHD comminution site, causing charge to be induced in the liquid at the tube ends 4002 A. This causes an electrically charged dispersion of droplets.

In another embodiment of the present invention, illustrated in Fig. 17, where elements common to the embodiments of Figs. 14 and 15 and the embodiment of Fig. 17 are referenced by the same reference numerals, an EHD spray device 5000 is provided having

a main housing 3010 comprising a base portion 3012 and a conical upper portion 3014. A refill bottle 100 comprising a container 102, a cap 106 and a wick (not shown) extending through a sleeve section 106B of the cap 106 are housed within the main housing 3010. In place of the crown-shaped first conductive element 3002 provided in the Fig. 15 embodiment, a permanent wick element (not shown) mounted in a wick holder 5003 is provided. The wick holder 5003 is coupled to the main housing conical upper portion 3014 via ribs or like supports (not shown). A plurality of first bores 501 OA defined within tube portions 5003 A of the wick holder 5003 and an internal cavity (not shown) defined within a base 5003B of the wick holder 5003 are provided, wherein the first bores 501 OA communicate with the internal cavity.

The permanent wick element is provided in the internal cavity and the first bores

501 OA of the wick holder 5003 and may comprise an open cell foam, packed fibers, a combination of open cell foam and packed fibers or any other material defining a liquid pathway through the wick holder 5003.

In the illustrated embodiment, the bottle wick upper portion abuts against an exposed portion of the permanent wick element. Ends 5003C of the tube portions 5003 A define EHD comminution sites.

During operation of the spray device 5000, liquid formulation flows from the container 102, through the wick 108, to the bottle wick upper portion and then through the permanent wick element to the tube portion ends 5003C. When the switching circuitry 36 is operated to activate the high voltage generator 32, grounded or low voltage at the wick holder 5003 and high voltage at the second conductive element 3006 results in a virtual positive electrode cloud and a strong electrical field being generated in the vicinity of the tube portion ends 5003C, each of which defines an EHD comminution site, causing charge to be induced in the liquid at the tube portion ends 5003C. This causes an electrically charged dispersion of droplets.

In still yet another embodiment of the present invention, illustrated in Fig. 18, where elements common to the embodiments of Figs. 14 and 15 and the embodiment of Fig. 18 are referenced by the same reference numerals, an EHD spray device 6000 is provided having a main housing 3010 comprising a base portion 3012 and a conical upper portion 3014. A refill bottle 100 comprising a container 102, a cap 106 and a wick (not shown) extending through a sleeve section 106B of the cap 106 are housed within the main housing 3010. In place of the crown-shaped first conductive element 3002 provided in the Fig. 15 embodiment, a permanent wick element 6002 mounted in a wick holder 6003 is provided. The wick holder 6003 is coupled to the main housing conical upper portion 3014 via ribs 3014A.

The permanent wick element 6002 may comprise packed fibers. In the illustrated embodiment, the bottle wick upper portion abuts against an exposed portion of the permanent wick element 6002. An end 6002 A of the permanent wick element 6002 defines an EHD comminution site. During operation of the spray device 6000, liquid formulation flows from the container 102, through the bottle wick, to the bottle wick upper portion and then through the permanent wick element 6002 to the permanent wick element end 6002A. When the switching circuitry 36 is operated to activate the high voltage generator 32, grounded or low voltage at the wick holder 6003 and high voltage at the second conductive element 3006 results in a virtual positive electrode cloud and a strong electrical field being generated in the vicinity of the permanent wick element end 6002A, which defines an EHD comminution site, causing charge to be induced in the liquid at the permanent wick element end 6002A. This causes an electrically charged dispersion of droplets.

In yet a further embodiment of the present invention, illustrated in Fig. 19, where elements common to the embodiments of Figs. 14 and 15 and the embodiment of Fig. 19 are referenced by the same reference numerals, an EHD spray device 7000 is provided having a main housing 7010 comprising a base portion 7012 and a conical upper portion 7014. A refill bottle 100 comprising a container 102, a cap and a wick 108 extending through a sleeve section 106B of the cap are housed within the main housing 7010. In place of the crown- shaped first conductive element 3002 provided in the Fig. 15 embodiment, a cutting element 7002 having a plurality of cutting parts 7002A parts is rotatably mounted to the main housing conical upper portion 7014.

Prior to operation of the spray device 7000, the bottle 100 is first coupled to the spray device 7000 via threadedly coupling a threaded connecting part 7011 of the main housing 7010 to a threaded neck portion (not shown) of the container 102. The container 102 is held stationary as the main housing 7010 of the spray device 7000 is rotated so as to cause the main housing connecting part 7011 to be threaded onto the container neck portion. As the connecting part 7011 is rotated, the cutting element 7002 remains stationary. However, the cutting parts 7002A on the cutting element 7002 engage and move into an outer or end portion 108A of the wick 108 as the spray device 7000 and bottle 100 are being coupled together, i.e., as the bottle wick end portion 108A moves relative to the cutting element 7002. Hence, the cutting parts 7002A separate the wick end portion 108 A into a plurality of sections 108B, four in the embodiment illustrated in Fig. 19, each of which defines an EHD

comminution site.

During operation of the spray device 7000, liquid formulation flows from the container 102, through the wick 108, to the wick upper portion sections 108B. When the switching circuitry 36 is operated to activate the high voltage generator 32, grounded or low voltage at the cutting element 7002 and high voltage at the second conductive element 3006 results in a virtual positive electrode cloud and a strong electrical field being generated in the vicinity of the wick upper portion sections 108B, each of which defines an EHD comminution site, causing charge to be induced in the liquid at the wick upper portion sections 108B. This causes an electrically charged dispersion of droplets.

In place of the cutting element 7002, a die (not shown) could be used so as to deform the bottle wick outer portion 108 A into two or more sections, each of which defines an EHD comminution site. The bottle wick outer portion 108 A is deformed into the two or more sections as the wick outer portion 108 A moves into and through the die.

While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.

Claims

1 ^00/ΐ¾ Δ Τη9ζΐρΒWO 2011/038171 PCT/US2010/050095 CLAIMS What is claimed is:

1. An electro-hydrodynamic (EHD) device in combination with a bottle comprising: a bottle comprising a container including a liquid formulation to be comminuted into a spray of droplets and a wick extending into said container, said wick having an end portion; and

an EHD device comprising:

a first conductive element including an end section defining an EHD comminution site, said first conductive element being at a first electrical potential and contacting and interfacing with said wick end portion; and

a second conductive element being at a second electrical potential, said first and second electrical potentials at said first and second conductive elements resulting in a strong electric field being generated in the vicinity of said first element end section.

2. The EHD device as set out in claim 1, wherein said first conductive element is formed from a high surface energy, electrically conductive material such that liquid formulation moves from said wick end portion to an end section of said first conductive element defining said EHD comminution site.

3. The EHD device as set out in claim 2, wherein said first conductive element comprises a plurality of end sections defining a plurality of EHD comminution sites.

4. The EHD device as set out in claim 2, wherein said first conductive element comprises a cylinder-shaped element into which said wick end portion is positioned, said cylinder-shaped element having at least one end section defining at least one EHD

comminution site.

5. The EHD device as set out in claim 2, wherein said first conductive element comprises a crown-shaped element into which said wick end portion is positioned, said crown-shaped element having a plurality of end sections defining a plurality of EHD comminution sites. 1 ^00/ΐ¾ Δ Τη9^ζΐρΒ

WO 2011/038171 PCT/US2010/050095

6. The EHD device as set out in claim 1, wherein said first conductive element comprises a plurality of capillary tubes formed from a high surface energy, electrically conductive material, and having end sections defining a plurality of EHD comminution sites.

7. The EHD device as set out in claim 1, wherein said EHD device further comprises a dielectric shroud positioned between said first and second conductive elements

8. The EHD device as set out in claim 7, wherein said second conductive element is located between said container and said first conductive element and generates a cloud of ions that forms a virtual electrode cloud near said first element end section.

9. A process for generating a spray of droplets from a liquid formulation using an electro-hydrodynamic (EHD) device in combination with a bottle comprising:

providing a removable bottle comprising a container including a liquid formulation to be comminuted into a spray of droplets and a wick extending into said container, said wick having an outer portion such that liquid formulation is conveyed along the wick to the wick outer portion via capillary action;

providing an EHD device comprising first and second conductive elements;

assemblying the bottle with the EHD device such that the bottle wick outer portion is positioned near the first conductive element; and

creating a strong electric field in the vicinity of at least one of the wick outer portion and the first conductive element by applying a first electrical potential to the first conductive element and a second electrical potential to the second conductive elements so as to generate a spray of liquid formulation droplets.

10. The process as set out in claim 9, wherein the first conductive element comprises a cylinder-shaped first conductive element and said positioning step comprising positioning the bottle wick outer portion within the cylinder-shaped first conductive element.

11. The process as set out in claim 9, wherein the second electrode is positioned away from the first electrode such that the second electrode generates a cloud of ions that forms a virtual electrode cloud near at least one of the wick outer portion and the first conductive element. 1 ^00/ΐ¾ Δ Τη9^ζΐρΒ

WO 2011/038171 PCT/US2010/050095

12. The process as set out in claim 9, further comprising replacing said bottle when empty with a refill bottle.

13. An electro-hydrodynamic (EHD) device comprising:

a housing having first and second sections and bottle-locating structure coupled to said first section, said bottle-locating structure capable of receiving and securing a first bottle comprising a container having a first geometry to said first section and, in place of said first bottle, is capable of receiving and securing a second bottle comprising a container having a second geometry different from said first geometry to said first section; and

an EHD control circuit associated with said housing.

14. The EHD device as set out in claim 13, wherein said bottle-locating structure comprises one or more movable locator lugs.

15. An electro-hydrodynamic (EHD) device in combination with a bottle comprising: a bottle comprising a container including a liquid formulation to be comminuted into a spray of droplets and a wick extending into said container, said wick having an outer portion; and

an EHD device comprising:

a first conductive element including an end section engaging and shaping said bottle wick outer portion to define two or more parts comprising EHD comminution sites, said first element being at a first electrical potential; and

a second conductive element being at a second electrical potential, said first and second electrical potentials at said first and second conductive elements resulting in a strong electric field being generated in the vicinity of said bottle wick outer portion.

16. The EHD device as set out in claim 15, wherein said first conductive element comprises a cutting element for cutting said bottle wick end portion into said two or more parts, each defining an EHD comminution site. 1 ^00/ΐ¾ Δ Τη9^ζΐρΒ

WO 2011/038171 PCT/US2010/050095

17. The EHD device as set out in claim 15, wherein said first conductive element comprises a die for receiving and forming said bottle wick end portion into said two or more parts, each defining an EHD comminution site.

18. The EHD device as set out in claim 15, wherein said EHD device further comprises a dielectric shroud positioned between said first and second conductive elements

19. The EHD device as set out in claim 18, wherein said second conductive element is located between said container and said first conductive element and generates a cloud of ions that forms a virtual electrode cloud near said bottle wick outer portion.