Anti drip fluid dispenser

The present invention provides a dispenser for dispensing a fluid which has an anti-drip feature. To achieve this anti-drip feature, the dispenser is provided with a suck back mechanism which is separate and independent from a pump in the dispenser. The suck back mechanism uses a resilient member capable of storing fluid.

FIELD OF THE INVENTION

The present invention generally relates to a fluid dispenser having an anti-drip feature.

BACKGROUND OF THE INVENTION

Fluid dispensers are known in the art for dispensing various viscous liquid and foam compositions. The viscous liquid and foam compositions are typically soaps, shampoos, creams, or lotions and are often found in public restrooms, restrooms in office buildings, and the like. One problem facing these fluid dispensers is at the end of a dispensing cycle a small portion of the fluid being dispense from the dispenser may remain at the exit port of the dispensing nozzle. This small portion of the fluid being dispensed can result in a condition called “stringing”, in which the small portion of the fluid remains attached to the fluid dispensed to the user. For example, when the fluid is dispensed into the user's hand, the small portion of fluid remains attached to both the fluid dispensed in the user's hand and the exit port of the nozzle. As the user withdraws their hand away from the exit port, the small portion of the fluid remains attached to both the user's hand and the exit port of the nozzle, creating an elongated string-like formation of the fluid. Stringing is especially a problem with foam compositions. Stringing can confuse a user, causing the user to focus on terminating the string, rather than the job at hand, for example, washing one's hands.

Alternatively, the small portion of the fluid may remain solely at the exit port of the nozzle. As gravity or other forces act on this small portion of the fluid, the small portion of the fluid may drip from the exit port of the nozzle onto a structure located beneath the exit port, such as a floor, a countertop, or sink. Alternatively, the small portion of the fluid may from a “string” of the fluid form the exit port to the structure beneath the exit port of the nozzle. In each of these situations, the viscous liquid dispenser gives the appearance of wasting the fluid and/or being of poor quality. In addition, having the fluid on surface beneath the nozzle of the dispenser and/or hanging from the exit port of the dispenser is often unsightly, creating a perception of an unclean restroom, and/or presenting a slip hazard to users of the restroom, when the fluid falls to the floor of the restroom.

In response to the dripping and stringing problems, pumps have been developed that have a suck back mechanism. This suck back mechanism creates a suction which draws the small portion of undispensed fluid away from the exit port. The prior art suck back mechanisms where built directly into the pump which draws the fluid from a reservoir. These mechanisms used the recovery/recharging cycle of the pump to draw the small portion of the undispensed fluid back towards the pump. One problem with this configuration is that the opposite forces are being applied to the pump at the same time, which may result in the pump with the suck back mechanism built into the pump operating in a manner which is undesirable. That is, the pump is caused to draw fluid from the reservoir at the same time the pump is drawing the portion of the undispensed fluid from the exit port of the dispensing nozzle. These opposite forces may make the pump susceptible to sticking or ineffectively drawing the fluid from the reservoir. As a result, to ensure proper operation of the pump, the prior suck back mechanisms have a complex structure.

There is a need in the art for a fluid dispenser with a suck back mechanism which operates independently from the pump mechanism and which has a relatively simple structure.

SUMMARY OF THE INVENTION

Generally stated, the present invention provides a dispenser for dispensing a fluid. The dispenser has a reservoir, a pump, a suck back mechanism, and a dispensing end. The reservoir is capable of holding a fluid which is to be dispensed from the dispensers. The pump is in communication with the reservoir. The pump has an inlet, an outlet and a recovery means. In addition, the pump has an idle or rest stage, a discharging stage, in which a shot of the fluid is expelled from the pump through the outlet, and a charging stage, in which a shot of the fluid is drawn from the reservoir through the inlet into the pump. The recovery means returns the pump to the idle stage from the discharging stage and through the charging stage. The suck back mechanism is separate from the pump. The suck back mechanism has at least one resilient member capable of storing fluid, a first opening, and a second opening. The first opening of the suck back mechanism is connected to the outlet of the pump and the resilient member is positioned between the first opening and the second opening of the suck back mechanism. The dispensing end of the dispenser has an exit port which allows the fluid to be dispensed from the dispenser and the dispensing end is connected, directly or indirectly, to the second opening of the suck back mechanism. At the end of the discharging stage of the pump, undispensed fluid remains between the dispensing end and the second opening of the suck back mechanism and a portion of the undispensed fluid is drawn into resilient member, independent of the recovery means of the pump.

In one embodiment of the present invention, the present invention provides a dispenser where the resilient member is prepared from an elastomeric material. The resilient member is a hollow member having a hollow portion and the hollow portion is capable of storing fluid. The resilient members of the present invention may be shaped to effectively store, intake and release fluids. In one particular embodiment of the present invention, the resilient members may have a corrugated shape or truncated cone shape.

In a further embodiment of the present invention, the suck back mechanism may be a single resilient member or a plurality of resilient members. In one particular embodiment, there are two resilient members present in the suck back mechanism.

In another embodiment of the present invention, the pump recovery means may be a compressible member. One example of a compressible member that may operate as the pump recovery means is a spring.

In another embodiment of the present invention, the suck back mechanism is a body having a first opening, a second opening, and a primary fluid pathway between the first and second opening. This primary pathway connects the first and second openings to one another. Also present is at least one secondary pathway having a first end and a second end, wherein the resilient member is located at the second end of the secondary pathway and the first end of the secondary pathway is located along primary fluid pathway.

In an additional embodiment of the present invention, the pump further has a housing having a fluid chamber comprising an interior wall, a piston positioned within the fluid chamber and a piston which is telescopingly movable within the fluid chamber. The piston creates a seal with the interior wall of the fluid chamber. The pump further has an inlet valve located at or near the inlet of the pump, and an outlet valve located at or near the outlet of the pump. In yet a further embodiment of the present invention, the housing further forms a second chamber having an interior wall. The piston is telescopingly movable within the second chamber and creates a seal with the interior wall of the second chamber. This second chamber has a second inlet and a second outlet, wherein the second outlet is located at or near the outlet of the pump and the second inlet is positioned within the pump such that it is on a side of the pump which does not come into contact with the fluid within the reservoir. In one particular embodiment of the present invention, the second inlet is an air inlet, which is adapted to allow atmospheric air to enter the second chamber of the pump, but will not allow atmospheric air in the second chamber to escape through the second inlet.

By providing the dispenser of the present invention, drawbacks of the dispensers with suck back mechanisms described above are minimized or eliminated.

DEFINITIONS

As used herein, the term “fluid” is intended to mean a body of material which is flowable at or about room temperature and pressure. The term is intended to mean gases, liquids and mixtures thereof as well as these materials that contain solids or particles. The term “precursor to the fluid” is intended to mean a material that forms a fluid when expelled from the dispenser. For example, a liquid may be a precursor to a foam dispensed from the dispenser.

As used herein, the term “charging stage” is intended to mean a phase of the pump in which fluid is being drawn from the reservoir, and, when the pump is a foaming pump, air being drawn into the air chamber of the pump.

As used herein, term “discharging stage” is intended to mean a phase of the pump in which fluid is being expelled from the pump through the outlet of the pump, and, when the pump is a foaming pump, air is being forced from the air chamber of the pump.

As used herein, the terms “idle stage” or “rest stage” is intended mean a phase of the pump in which the pump is neither charging or discharging a fluid.

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description of the present invention, reference is made to the accompanying drawings which form a part hereof, and which show by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that mechanical, procedural, and other changes may be made without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled.

Referring toFIGS. 1,2, and3, provided by the present invention is a dispenser10for dispensing a fluid. Generally, the dispenser10has a reservoir12, a pump14(shown inFIG. 2), a suck back mechanism16and a dispensing end18. The reservoir12is capable of holding a fluid22(shown inFIG. 2) which is to be dispensed from the dispenser10. The pump14is in communication with the reservoir12such that the pump14may draw the fluid from the reservoir12into the pump, through dip tube67.

In one embodiment, referring toFIGS. 1 and 3, reservoir12includes a main container121and a top portion122.FIG. 1shows the top portion122on the main container121andFIG. 3shows the top portion removed from the main container121, so that the internal works of the reservoir may be viewed. The main container121serves to hold and contain the fluid or the precursor to the fluid that is to be dispensed from the dispenser10and will generally have an opening, which is not shown inFIGS. 1 and 3. The main container may also have a neck124near the opening, wherein the neck124of the main container forms the opening in the main container121. Generally, the top portion122is attachable to the main container121at neck124of the main container121. The top portion122may be secured to the main container121in a manner such that the top portion122is removably secured to the main container121or such that the top portion122is permanently secured to the main container122. For example, the top portion122may be sealed to main container121using ultrasonic welding, adhesive or other suitable means of effecting a permanent attachment of the top portion122to the main container121. If it is desirable that the top portion122is removable from the main container121, the top portion122could be mated to the main container121using known methods, such as providing threads (not shown) on the top portion122and complementary threads128on the main container121, as is shown inFIG. 3. Other similar methods could be used to removably secure the top portion122to the main container121.

Located within the main container121is a pump14, shown inFIG. 2. As shown inFIG. 2, the pump is located in the opening123of the main container121, generally in the neck124of the main container. It is also possible that the pump14may be located in the top122of the reservoir12, or located at the bottom of the main container121. For the purposes of describing the present invention, the pump will be described as being generally located in the neck124of the main container121. Generally speaking, the pump14has an inlet141, an outlet142and a recovery means143. As with most pumps, the pump14has an idle stage, a discharging stage, and a charging stage. In the idle stage, which is shown inFIG. 2, the pump14mechanism is at rest and is not actively charging or discharging the fluid. The discharging stage of the pump is a stage in which a shot of the fluid is expelled from the pump14through the outlet142of the pump. In the charging stage of the pump14, a shot of the fluid22is drawn from the reservoir12through the inlet141into the pump14. The recovery means143allow the pump14to return to the idle stage from the end of the discharging stage. As the pump14is returning to the idle stage from the end of the discharging stage, the pump14is in the charging stage. Further details of a pump14usable in the present invention will be described below.

The suck back mechanism16is separate and distinct element from the pump14. Generally described, a suck back mechanism16usable in the present invention is shown inFIGS. 5 and 5Ain an exploded view. The suck back mechanism16has at least one resilient member161capable of storing fluid, a first opening162and a second opening163(shown inFIGS. 3,4,5and5A). The resilient member161is positioned between the first opening162and the second opening163of the suck back mechanism16. The dispensing end18of the dispenser10allows the fluid to be dispensed from the dispenser10and the dispensing end18is connected to the second opening163of the suck back mechanism16. At the end of the discharging stage of the pump14, undispensed fluid remains between the dispensing end18and the second opening163of the suck back mechanism16and a portion of the undispensed fluid is drawn into resilient member161, which prevents the undispensed portion from dripping out of the dispensing end18and helps prevent stringing of the fluid dispensed to the user with the undispensed fluid.

The suck back mechanism16may operate independently from the pump14or may operate in conjunction with the pump14. When operated separately from the pump, the suck back mechanism does not rely upon the recovery means143of the pump. When operated in conjunction with the pump, the pump's recovery means143assist recovery of the resilient members during the charging stage of the pump. The first opening162of the suck back mechanism16is connected to the outlet142of the pump14.

As shown inFIG. 2, the dispenser10may be provided with a pump mounting element20, which is also shown inFIGS. 3 and 4. This pump mounting element20may be used to hold and/or secure the pump14and the suck back mechanism16within the dispenser. The pump mounting element20fits into the opening123of the main container121, which is shown inFIGS. 2,3and4and may be permanently mounted in the opening or removably mounted in the opening. Alternatively, the pump mounting element20may be associated with the top portion122of the dispenser. That is, the pump mounting element20may be removably connected to the top portion122of the reservoir. In another alternative configuration, the pump mounting element20may be permanently connected with the top portion122of the dispenser such that the pump mounting element20forms a bottom surface of the top portion122. Alternatively, the pump device12may be housed within the main container121.

As is shown inFIG. 2, the pump device14is located inside the neck124of reservoir12as described above and serves to draw the fluid or fluid precursor22from the main container121of the reservoir12and force the fluid out the dispensing end18of the dispenser10. The pump device14may be advantageously constructed from widely available “stock” components in order to enhance manufacturing efficiencies. Specifically, pump device14is preferably a common lotion pump of the type in widespread use with bottled lotions, shampoos, soaps and the like. Suitable pumps may be purchased from a variety of pump manufactures including, for example Rexam Airspray, Inc., having offices at 3768 Park Central Blvd, North, Pompano Beach, Fla., USA, and Rieke Corporation 500 W.7thStreet, Auburn, Ind., USA. A suitable commercially available pump is the F2 foaming pump available from Rexam Airspray, Inc. Many other models of foam pumps, lotion pumps are also available on the market, and may be utilized depending on variables such as shot size and the like. As will be explained below, a commercially available pump device may be modified in several ways for use in dispenser10, depending on the application or fluid to be dispensed from the dispenser10.

To gain a better understanding of an exemplary pump that may be used in the present invention, attention is again directed toFIG. 2. As shown, pump device16is a foaming pump and includes an outer tubular piston62and an inner tubular piston64located inside of a pump cylinder66. As is shown, the pump cylinder66has a wide portion66W and a narrow portion66N. The outer tubular piston62, the wide portion66W of the pump cylinder66and the outer surface of the inner piston64form a first chamber68, which is an air chamber. The inner piston64and the narrow portion66N of the pump cylinder66form a second chamber69, which is the fluid chamber. The pump device16further includes a cap element70, which is maintained in an axially fixed relation with respect to pump cylinder66. Cap element70is advantageously used to mount the pump device16within reservoir12, and as shown, more particularly; to the pump mounting element20, which is either contained within the main container121or the top portion122of reservoir. In the illustrated embodiment, for example, pump mounting element20is configured as a disc-shaped member having a threaded portion76. The outer threads of threaded portion76are engaged by the inner threads of cap element70, as shown inFIG. 2. Other suitable means may be used to hold the pump assembly16in the reservoir12.

An engaging element24is in communication to the pump's piston assembly61. Typically, the engaging element will be physically connected to the piston61. In the illustrated embodiment, engaging element24is configured having a cylindrical portion79, and a disc-shaped flange80. It is generally the cylindrical portion79which is connected to the piston61of the pump14. Typically, the engaging element24is generally located near the central axis of the reservoir, which provides advantages discussed below. Reciprocative movement of engaging element24will cause piston assembly61to move within the pump cylinder66. Piston assembly61is normally urged into an upward position (rest position), shown inFIG. 2, due to the force of a pump recovery means143. The pump recovery means may be a compressible member or, in an electronic configuration, the motor may be used to recover the pump. Suitable pump recovery means includes a helical spring, as is shown inFIG. 2.

As is stated above, the pump assembly14shown inFIG. 2is a foaming pump. The foaming pump shown mixes the liquid22from the main container121with air within the pump structure. The outer piston62contains air inlet openings72, which allow air to pass through the outer piston62to enter the air chamber68. In addition, the outer piston62is provided with an air exhaust passage73, which allows the air present in the air chamber68to escape the air chamber68. To prevent air in the air chamber from exiting the air inlet opening72, a check valve74is positioned near the air inlet opening72which opens during the charging stage and closes during the discharging stage of the pump14. This check valve74also prevent air and/or fluid from entering the air chamber68during the charging stage from the air exhaust passage73during the charging stage of the pump. Operation of this check valve is described in more detail in U.S. Pat. No. 5,443,569 to Uehira et al., which is hereby incorporated by reference.

Pump device16is further provided with additional check valves84,85and86to ensure proper flow of the liquid through the pump. Check valve86, located at the base of pump cylinder66, allows the liquid22to be drawn into a lower liquid chamber69, through the inlet141of the pump when inner piston64moves in an upward direction (charging stage). When inner piston64moves in a downward direction (discharging stage), check valve,85allows the liquid22to be passed into an upper liquid chamber90from the lower liquid chamber69. In addition, check valve84allow fluid to exit the upper pump chamber90into the mixing chamber92. Both check valves84and85are opened at the same time and close at the same time. In the mixing chamber92, air from the air chamber68is mixed with the liquid22from the upper liquid chamber90. The mixing of the air and liquid creates a foam fluid which is forced through a porous member93. The porous member93is in the form of a porous net or screen-like structure to create uniformity in the foam bubbles of the fluid. The fluid is then force through the outlet142of the pump14.

While a variety of different check valve configurations are contemplated, the illustrated embodiment utilizes common ball and seat valves. Other configuration of these elements may be used without departing from the scope of the present invention. Other structures and functional elements, such as seals and gaskets may be used in the pump device to the pump form leaking or improve the function of the pump. Further it is noted that the pump assembly14described above is a foaming pump and that non-foaming pumps may also be used in the present invention. Non-foaming pumps work much in the same manner as the foaming pump described above, but are devoid of outer piston, air chamber, air inlet and mixing chamber described above. The liquid is passed through the pump in the same manner as the foaming pump but is not mixed with air prior to leaving the pump outlet142.

Referring toFIGS. 2,3and4, the fluid leaving the outlet142of the pump14is transported to the suck back mechanism16. Generally, the outlet142of the pump14typically moves with the piston assembly61. To counter act this movement, the outlet142of the pump14is joined to the first opening162of the suck back mechanism16with a flexible tube96. The flexible tube96has a first end97attached to the outlet142of the pump and a second end98attached to the first opening162of the suck back mechanism16. By connecting the outlet142of the pump14with the suck back mechanism16with the flexible tube, the suck back mechanism16can be mounted to the pump mounting member20in a stationary manner, which will improve the operation of the suck back mechanism16during use. As is shown inFIG. 2, the suck back mechanism16is mounted on a mount179.

Attention is directed toFIGS. 5 and 5A, which each show a configuration usable for the suck back mechanism. As is stated above, the suck back mechanism16is provided with a first opening162, which functions as an inlet for the fluid being pumped from the pump14into the suck back mechanism16. The suck back mechanism16also has a second opening163, which functions as an outlet from the suck back mechanism16when the pump14is in the discharging stage. The second opening163also functions as an inlet for a portion of any undispensed fluid between the suck back mechanism16and the dispensing end18of the dispenser, when the pump14is in a charging stage. The suck back mechanism16also has at least one resilient member161, which is capable of drawing a portion of any undispensed fluid between the second opening162of the suck back mechanism16and the dispensing end18into resilient member161. The function of the resilient member may be independent of the recovery means143of the pump14or may be aided by the recovery means143of the pump14.

Generally, there are one or more resilient members161in the suck back mechanism. The resilient member(s)161are shaped and are prepared from a material which allow the resilient member(s) to be compressed and recover to essentially it same size and shape. Exemplary shapes for the resilient member161are shown inFIGS. 7 and 8.FIG. 7shows a corrugated bellows shape andFIG. 8shows a resilient member having a truncated cone shape. The resilient member is prepared from an elastomeric material, including for example, natural rubber, a silicone rubber, or any other material which is elastomeric in nature. Alternatively, other resilient materials may be used, so long as the material is capable of recovering from a compressed state. The actual size of the resilient members can be selected by those skilled in the art to create the ideal suction force needed to allow the resilient members to effectively intake the fluid and/or create a desire level of vacuum to effectively draw the fluid into the suck back mechanism. Generally, higher viscosity fluids will require a larger volume in the hollow portions of the resilient members.

In one embodiment is shown inFIG. 5, a plurality of resilient members161are used in the suck back mechanism16. Specifically, two resilient members161are shown. As shown, the suck back mechanism16has a lower member164and an upper member165, which is joined to the lower member164. The upper member165and the lower member164should form an air tight seal when joined together. Additional seals or sealing materials may be used to ensure that combination of the upper and lower members165and164are air tight. Such seals and sealing members would readily be apparent to those skilled in the art. The upper member164has a seat168which adapted to create a seal with the resilient members161. The resilient members161may be held in place on the seat168with a retainer166or any other suitable means to maintain an air tight seal in the suck back mechanism. Typically, the retainer166will snap into place onto the upper member165to securely hold the resilient members in place during use. Again, the resilient members161should create an air tight seal with the upper member165. If the suck back mechanism16does not have an air tight seal, the suck back mechanism16may not operate in a proper manner.

In addition to forming an air tight seal, in one embodiment of the present invention, the upper member164and lower member165, when joined together, should create a channel or passage174. This channel or passage174connects the primary fluid passageway175through the suck back mechanism16to the resilient members161and the hollow portion173of the resilient member161, thereby allowing the suck back mechanism to draw a portion of the undispensed fluid into the hollow portion173of the resilient members161. This channel or passage174also allows the portion of the undispensed fluid drawn into the hollow portion173to exit the hollow portion173of the resilient member161to be placed back into the primary fluid passageway175.

In an alternative configuration, a single resilient member161may be used in the suck back mechanism16. When a resilient member161is used, it can be formed using a structure shown inFIG. 5, where one of the resilient members is removed and the retainer166holds a cap (not shown) or creates a seal with seat168. Alternatively, a structure similar to that shown inFIG. 5Amay be used for the suck back mechanism16, when a single resilient member161is used. As is shown inFIG. 5A, the suck back mechanism16has an inlet162, and an outlet163. A passageway171is created between the inlet162and the outlet163and the passageway as vents170, which allow the fluid to pass from the passageway into the resilient member161. The resilient member161should create a seal with the passageway171to ensure that the suck back mechanism will operate properly. Other similar structures may be used in the present invention as the suck back mechanism, provided that the structures allow undispensed fluid between the pump and the dispensing end of the dispenser.FIG. 6is similar toFIG. 3described herein, exceptFIG. 6shows a suck back mechanism ofFIG. 5Ain use on the reservoir12.

Generally, the suck back mechanism16may be held in the pump mounting element20with a suitable mounting means. For example, the suck back mechanism16would be provided with mounting structure167on the upper member165of the suck back mechanism. The mounting structure could be a hole or protrusion which would allow the suck back mechanism16to be mounted on a mount179, which is present on the pump mounting structure20. The suck back mechanism16could be adhered to the mount179using an adhesive, or the suck back mechanism16could be mechanically attached to the mount179using a mechanical mounting means, such as a screw. Any other mechanical mounting means may be used so long as the suck back mechanism16is stationary within the pump mounting element20.

As is shown inFIG. 2, the resilient member161is generally hollow structures having an opening172located near the portion of resilient member161which is to be positioned at or near the seat168. The hollow portion173of the hollow structure allows the resilient member161to store the fluid. In addition, the hollow structure of the resilient member is allowed to collapse, thereby forcing the fluid within the reservoir out of the reservoir. As the resilient member161returns to its original shape and size, a vacuum is created by the hollow portion173, which causes the fluid to be refilled in the resilient member.

The fluid exits the suck back mechanism16at the second opening163and the fluid exits the dispenser10through the dispensing end18of the dispenser. The dispensing end18may be located at a distal end19D of a tube19which is connected to the second opening163of the suck back mechanism16at a proximate end19P of the tube19. This is shown inFIGS. 1 and 2. In an alternative embodiment, the dispensing end18may be in the form of a nozzle (not shown in the drawings). Generally, when the tube19is present, the tube19prepared form a flexible material.

Additional elements which may be present in the dispenser10of the present invention include an actuator26, and an actuator rod30. The actuator26is operable connected to the outer piston62of the pump14, as is shown inFIG. 2. The actuator serves to activate the pump14, causing the pump to move from a resting stage, shown inFIG. 2, to a discharging stage, moving liquid from the reservoir12through the pump14, suck back mechanism16and out of the dispensing end18of the dispenser10. As is shown inFIG. 2, the actuator26has a upper structure27and a lower structure28. The upper structure27is joined to the lower structure28with a connecting side structure29. Generally there are more than one side structures29present in a single actuator26, so that the upper structure27of the actuator and the lower structure28work in unison as a single unit. The structure of an actuator usable in the present invention can be further seen inFIGS. 3 and 6. One further element that may be present in a filling port23, which allows the reservoir12to be filed with the fluid.

As can be seen inFIGS. 2,3and6, a lower surface31of the upper actuator structure27may contact the resilient members161. By having the actuator26contact the resilient member161, as the actuator is moved from its rest position, as shown inFIGS. 2,3and6to its depressed position, shown inFIG. 2, the lower surface31of the actuator's upper structure compresses the resilient members161, thereby forcing the fluid present hollow portion from the resilient member161into the channel175and subsequently out of the dispensing end18of the dispenser. The lower surface31of the actuator's upper structure27may merely contact the resilient member161or may be physically joined to the resilient members. Suitable method of joining the lower surface31to the resilient member161includes, for example, adhesive means, mechanical means or a combination of adhesive and mechanical means. Having the resilient member161joined to the lower surface31has the advantage that the pump recovery means143can be used to assist the resilient member161in recovering to its starting shape and size, creating a vacuum to draw the fluid from the dispensing end18back towards the suck back mechanism16. However, it is not necessary to have the resilient member131connected to the lower surface31of the upper actuator structure27.

To activate the actuator26to dispense the fluid from the dispenser10, an actuator rod30contacts the top surface32of the actuator, as is shown inFIG. 2. Alternatively, the actuator rod may be connected to the top surface32of the actuator26. The actuator rod30may contact the top surface32of the actuator26by passing though an actuator opening130, shown inFIGS. 1 and 3, located in the top portion122of the reservoir assembly12. The actuator opening130, is generally positioned about the center line of the top portion122. In one embodiment of the present invention, the tube19, connecting the dispensing end18to the second opening163of the suck back mechanism16, will be centrally located in the actuator opening130, as is shown inFIG. 1. The actuator opening130may be a single opening such that the actuator rod30can come into contact with top surface32of the actuator26.

As the actuator rod30depresses the actuator26, the actuator26depresses the resilient members161and depresses the outer tubular piston62and an inner tubular piston64of the pump, transitioning the pump14from the rest stage to the discharging stage. Depressing the resilient members161causes any fluid within the hollow portion173to be expelled from the resilient members161into the primary fluid passageway175and towards the dispensing end18of the dispenser. In addition, fluid is expelled from the pump14through the outlet142of the pump into the flexible tube96, which carries the fluid to the suck back mechanism16. The fluid enters the primary passage175of the suck back mechanism16and joins the fluid expelled from the resilient member161. The fluid is also expelled from the dispensing end18of the dispenser10. At the end of the actuator's26depressing the resilient member161and the pistons of the pump, the pump recovery means143causes the pump to transition from the discharging stage to the charging stage. During the charging stage of the pump14, the actuator26is returned to its rest position, shown inFIG. 2, which in turn allows the resilient member161to return to its original shape from a compressed state. As the resilient member161is returned to its original shape, a vacuum is created, causing a portion of any undispensed fluid between the suck back mechanism16and the dispensing end18to be drawn back into the resilient member161. It is this vacuum created and the drawing of the portion of the undispensed fluid into the resilient member161, prevents the problems of stringing and dripping from the dispensing end18of the dispenser.

The dispenser10of the present invention may be used as an under-counter dispenser, such as the one shown inFIG. 9. When used as an under-counter dispenser, the actuator rod30may be manually activated by a user, by having the end of the actuator rod30opposite the actuator operably connected or in contact with an actuation button222. As the actuation button222is depressed by the user, the actuator rod depresses the actuator26, which in turns activates the pump14and suck back mechanism16as stated above. Typically, the actuator button222is located on a dispensing head220. The dispensing head220also has a delivery spout224. Holding the dispensing head220to the counter (not shown) is a anchoring mechanism228, which is associated with a portion of a generally hollow elongated tube226which extends below the counter. In the hollow portion of the elongated tube226is the actuator rod30. At the end of the elongated tube226opposite the dispensing head220is a connecting member230. The dispenser has complementary connecting members40located on the dispenser10, which serve to connect the dispenser to the dispensing head220and/or the elongated tube. In this configuration, the tube19is inserted through the connecting member230, through the elongated tube228and into the delivery spout224so that the dispensing end is at or near the end221′ of the delivery spout. In the configuration shown inFIG. 9, the dispenser is manually operated by the user.

In an alternative embodiment of the present invention, the pump14and suck back mechanism16is electronically activated. An example of an electronic viscous liquid dispensing system is shown inFIG. 10. An electronically activated pump may operate in many different ways. One way is to have a user push an actuation button222located on or near the dispensing head or to provide a sensor223which would detect the users hands under the spout20. When used as an electronic activation of the pump, the actuation button may be a push button, a sensor or any other means known to those skilled in the art to electronically activate the pump.

As can be seen inFIG. 10, the electronic viscous liquid dispensing system has a dispensing head220, and elongated tube226, a motor housing202, a power pack housing204, a connecting member230and a reservoir assembly12. Essentially the components are similar or are the same as described above with the exception that the motor housing202is positioned between the elongated tube226and the connecting member230. In addition the power pack housing204contains a power supply which is electrically connected to a motor. The dispensing head220has an actuator button222, and/or a sensor223which is used to activate a motor which engages the pump14by the actuator rod30and the actuator. The actuator button222and/or the sensor223are electrically connected to the motor. Generally, the actuator button222and/or the sensor223are electrically connected to a control panel (not shown) having control circuitry which is used to detect a user's hand near under the spout224, or the user's input to the actuator button222. In addition, the control circuitry is used to activate the motor for a given period of time so that the user receives a dose of the viscous liquid. Control circuitry for sensors and buttons is known to those skilled in the art and is shown, for example in U.S. Pat. No. 6,929,150 to Muderlak et al., which is hereby incorporated by reference.

In the electronic viscous liquid dispensing system, the connecting member230may be connected to the motor housing202and power supply housing204. Alternatively, the motor housing202may be integral with the connecting member230, meaning that the motor housing202and connecting member230are a single unit. Typically, the power supply204may be separated from the motor housing so that the power supply may be replaced when needed. That is, the power supply is disconnectable and reconnectable to the motor housing. To ensure that power is transferable from the power supply204to the motor housing, electrical contact points may be used on both the motor housing and power supply, such that the electrical contact points are in complementary positions, meaning that when power supply is attached to the motor housing an electrical connection is made.

To gain a better understanding of a possible configuration of the motor housing202, attention is now directed toFIGS. 11A, B, C and D. The motor housing202houses a motor210, gears211,212which are engaged with motor210and an additional gear213which drives an actuator rod30. The motor driven actuator rod30is housed in the motor housing202and extends from the motor housing202through an opening present in the lower surface of the connecting member230. Any method may be used to drive the motor driven actuator rod30. In a typical operation of the electronic viscous liquid dispensing system, the motor driven actuator rod30contacts the actuator26and pushes the actuator downward to activate the pump14one or more times to expel a dose of the viscous liquid from the spout224of the dispensing head220.

Numerous ways may be used to transfer power from an activated motor to the motor driven actuator rod30. For example, the motor may drive a series of wheels, gears or other energy transmission means to the actuator rod30which extends and contacts the actuator26. In one embodiment of the present invention, which is intended to be an exemplary means that may be used to drive the actuator rod30, the drive wheel213has a post or shaft214extending from one area of the gear body near the periphery215, as is shown ifFIG. 11A and 11B. As the motor210turns the motor drive wheel211, the motor drive wheel211in turn rotates one of more wheels212. InFIG. 11A, a single wheel212is shown; however, it may be desirable to have more wheels to reduce the rotational speed of the actuator drive wheel213, so the pump is activated in a controlled manner. It is within the skill of those skilled in the art to select the ratio of drive wheel so that the appropriate speed is achieved of the actuator drive wheel213. It is noted the term “wheel”, as used herein is intended to cover any wheel like mechanism, including wheels per se and other wheel-like mechanisms such as gears. Generally, gears are desirable, since gears are less likely to slip during use.

As is shown inFIG. 11B, the actuator drive wheel213has a shaft214extending from a non-central area of the actuator drive wheel213, which makes the shaft rise and lower in the direction325as the actuator drive wheel213turns. This shaft214is fitted into a horizontal channel322present in the actuator guide member320. The horizontal channel322is generally in the horizontal axis2. The horizontal channel322is created by two horizontal protrusions321and321′ extending from one of the sides of the actuator guide member320. As the actuator drive wheel turns, the shaft214travels in a circular path and has a vertical movement325in the vertical axis1, shown inFIG. 11Band a horizontal movement326in the horizontal axis2, shown inFIG. 11C. The vertical movement325of the shaft214causes the actuator guide member320to move up and down in the vertical axis1, which in turn moves causes the motor driven actuator rod30to also move in an up and down manner in the vertical axis. Below the channel322present on the actuator guide member320is the actuator rod30. The actuator guide member320is held in place so that the movement of the actuator guide member is in an up and down manner in the vertical axis and not side to side or front to back. The actuator guide member320may be held in place, for example by providing vertical guide slots323so that the lateral sides of the actuator guide member320are held in place on the horizontal axis. These vertical guide slots323maybe provided in the motor housing202as is shown inFIGS. 11B,11C and11D.

As is mentioned above, the shaft214also has a horizontal movement326in the horizontal axis2. This horizontal movement is essentially unwanted. To account for the horizontal movement, the shaft is allowed to move horizontally in the horizontal axis2along the channel322in the actuator guide member. Therefore, the channel322controls the essentially unwanted horizontal movement326of the shaft214.

The electrical powered viscous liquid dispensing systems may also have additional features. For example, dispensing head220may have indicator lights to signal various events, such as, recognition of a user, low battery, empty soap reservoir, or other conditions such as a motor failure. Examples of such lights include low power consumption lights, such as LED (light emitting diodes).

The power source for the electronic viscous liquid dispensing system of the present invention may include disposable DC batteries (not shown). Alternatively, the power supply may be a closed system which requires that the entire power supply be replaced as a single unit. Although not shown in the figures, an AC to DC adapter may be utilized to provide an alternate source of power to the viscous liquid dispenser. This embodiment may be particularly useful wherein the viscous liquid dispenser is mounted in close proximity to an AC outlet or when it is desirable to power multiple dispensers from a centrally located transformer of suitable configuration and power. The number of batteries used to power the motor will depend on the motor selected for the dispenser. Disposable batteries usable in the present invention include 9 volt batteries, 1.5 volt batteries, such as D-cell or C-cell batteries, or other similar batteries. The exact type of battery selected for use is not critical to the present invention so long as the power supplied to the motor is compatible for the motor. For applications where the viscous liquid dispenser will be used under low usage situations, rechargeable batteries could be used. If the dispenser is to be used in a bright light situation, the batteries could be solar rechargeable batteries.