Patent Publication Number: US-9850059-B2

Title: Closed system for venting a dispenser reservoir

Description:
RELATED APPLICATIONS 
     This patent application claims priority to patent application Ser. No. 61/968,058, titled CLOSED SYSTEM FOR VENTING A DISPENSER RESERVOIR, filed on Mar. 20, 2014, which is incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The current invention relates generally to fluid product dispensers and in particular to dispenser reservoirs. More specifically, the invention relates to ways of venting the reservoir during the dispensing process. 
     BACKGROUND OF THE INVENTION 
     It is known to dispense hand care products from a dispenser mounted to a wall, counter or dispenser stand. Dispensers may be conveniently located in building entrances, bathrooms, or lunchrooms providing convenient accessibility to passersby. Such dispensers may have a replaceable reservoir, also called a refill unit, containing hand soap, lotion or sanitizer. Replaceable reservoirs provide a sanitary solution to the problem found in refillable dispensers, which is that over time germ-laden bio-films form inside the fluid container and dispenser nozzle. 
     Replaceable reservoirs are often installed into dispensers in an inverted manner, which takes advantage of gravity to draw fluid out of the container. The reservoirs are connected to a pump, which pressurizes the fluid and meters out a predetermined amount of product. In many systems, the reservoirs are sealed from exposure to the atmosphere. As such, air cannot displace the fluid being pumped out of the reservoir thereby creating a vacuum inside the container. This makes it harder to draw fluid out of the reservoir and as such additional energy is needed to operate the pump. In systems using an onboard power supply this shortens the useful life of the power supply. 
     To overcome this problem, some reservoirs are constructed using thin gauge material. Thin-walled reservoirs are prone to collapse under atmospheric pressure as fluid is removed from the container. While the problem associated with vacuum pressure is somewhat alleviated, the thin gauge walls are susceptible to damage. Moreover, it is hard to read how much fluid is remaining in the refill reservoir because thin walls collapse unevenly and unpredictably. 
     Some systems vent ambient air directly into the refill reservoir to displace fluid dispensed from the system. While this relieves the vacuum pressure, it adds to the likelihood that germs, bacteria or other pathogens will be introduced into the system. 
     It would therefore be advantageous to use a rigid bottle that has side walls utilizing heavier gauge material if there was a way to vent the bottle without introducing contaminants into the replaceable reservoir. The embodiments of the current invention obviate the aforementioned problems. 
     SUMMARY OF THE INVENTION 
     In one embodiment of the subject invention, a dispensing system is provided that uses a replaceable reservoir for storing fluid product. The replaceable reservoir comes assembled with a pump and nozzle. The pump includes a vent that introduces air into the reservoir when fluid has been dispensed from the system. A bladder is connected to the inlet end of the pump assembly and positioned within the reservoir. Air vented into the reservoir is captured within the bladder and prevented from contacting the remaining fluid in the reservoir. 
     In one particular embodiment of the dispensing system, the bladder is generally oval or spherical is shape. In another embodiment, the bladder is shaped like a bellows or accordion. 
     In another embodiment of the subject invention, a refill unit for an associated dispensing system dispensing an associated liquid product includes: a reservoir defining an internal region for storing an associated liquid product, wherein the internal region is sealed from exposure to ambient air, wherein the reservoir includes an aperture through which the associated liquid product is operatively dispensed without exposing the internal region to ambient air; an air-tight variable volume bladder disposed within the internal region of the reservoir, the air-tight variable volume bladder defining an expandable bladder volume region that is sealed with respect to the internal region of the reservoir, wherein the air-tight variable volume bladder includes an inlet; and, wherein the reservoir includes an orifice open to ambient air and wherein the inlet of the air-tight variable volume bladder is connected to the orifice in a sealed manner to prevent exposure of the internal region of the reservoir to ambient air, and wherein the air-tight variable volume bladder expands when associated liquid product is operatively dispensed from the reservoir. 
     In one aspect of the embodiments of the subject invention, the refill unit also includes a check valve operatively connected to the aperture for allowing associated liquid product to flow from the reservoir, wherein the check valve inhibits ambient air from entering into the reservoir through the aperture. 
     In yet another aspect of the embodiments of the subject invention, the air-tight variable volume bladder is comprised of one or more walls constructed from pliable material. 
     In still another aspect of the embodiments of the subject invention, the air-tight variable volume bladder is comprised of one or more walls constructed from elastically deformable material. 
     In even another aspect of the embodiments of the subject invention, the air-tight variable volume bladder is comprised of one or more walls constructed from semi-rigid material separated by pleats that allow the one or more walls to fold and unfold thereby creating the expandable bladder volume region. 
     In still yet another aspect of the embodiments of the subject invention, vacuum pressure is generated within the internal region when associated liquid product is dispensed from the reservoir, and the air-tight variable volume bladder expands proportionally to the magnitude of vacuum pressure generated within the internal region. 
     In another embodiment of the subject invention, a refill unit for an associated dispensing system dispensing an associated liquid product includes: a reservoir defining a volumetric region for storing an associated liquid product, the reservoir including an aperture through which the associated liquid product is operatively dispensed; an expandable bladder constructed from pliable material, the expandable bladder being positioned within the volumetric region, wherein the expandable bladder is sealed in an air tight manner from the volumetric region of the reservoir, and wherein the expandable bladder includes a bladder inlet; a pump having a pump housing attached to the aperture of the reservoir in a sealed manner thereby preventing the volumetric region from exposure to ambient air, wherein the pump includes a pump inlet fluidly connected to the volumetric region for dispensing associated liquid product without exposing the volumetric region to ambient air; and wherein the pump housing includes an orifice having an orifice inlet exposed to ambient air and an orifice outlet connected in an air-tight manner to the bladder inlet. 
     In one aspect of the embodiments of the subject invention, the pump includes a check valve that allows associated fluid product into the pump and that prevents ambient air from entering the volumetric region. 
     In another aspect of the embodiments of the subject invention, the expandable bladder is constructed from elastically deformable material and wherein the expandable bladder is expandable from a first volume to a larger second volume when associated fluid product is pump from the reservoir; and the refill unit also includes a locking ring fixedly attaching the expandable bladder to the pump housing. 
     In yet another aspect of the embodiments of the subject invention, the pump housing includes an annular groove; and, wherein the locking ring compresses the material of the expandable bladder against the groove thereby creating an air tight seal. 
     In still another aspect of the embodiments of the subject invention, the expandable bladder is comprised of a plurality of walls constructed from semi rigid material, wherein the plurality of walls are separated by pleats that allow the plurality of walls to fold together in a first volume and that allow the plurality of walls unfold in a substantially larger second volume. 
     In even another aspect of the embodiments of the subject invention, the reservoir is constructed from semi-rigid material. 
     In another embodiment of the subject invention, a refill unit for an associated dispensing system dispensing an associated product, includes: a reservoir defining a volumetric region for storing an associated product, wherein the reservoir includes an aperture and an orifice; a pump attached to the aperture of the reservoir in a sealed manner, wherein the pump includes a pump inlet fluidly connected to the volumetric region; a variable volume bladder disposed within the volumetric region of the reservoir, wherein the variable volume bladder is sealed with respect to the volumetric region of the reservoir, wherein the variable volume bladder includes an inlet; and wherein the orifice is open to ambient air and wherein the inlet of the variable volume bladder is connected to the orifice of the reservoir in a sealed manner to prevent exposure of the internal region of the reservoir to ambient air. 
     In one aspect of the embodiments of the subject invention, the pump is a piston pump, which may include a check valve for allowing associated liquid product to dispense from the reservoir, wherein the check valve prevents ambient air from entering the volumetric region. 
     In another aspect of the embodiments of the subject invention, the reservoir is constructed from semi-rigid material. 
     In yet another aspect of the embodiments of the subject invention, the variable volume bladder is comprised of one or more walls constructed from pliable material. 
     In still another aspect of the embodiments of the subject invention, the variable volume bladder is comprised of one or more walls constructed from elastically deformable material. 
     In even another aspect of the embodiments of the subject invention, the variable volume bladder is comprised of one or more walls constructed from semi-rigid material separated by pleats that allow the one or more walls to fold and unfold thereby allowing the bladder to have a variable volume. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts a fluid dispensing system according to the embodiments of the subject invention. 
         FIG. 2  depicts a replaceable refill unit of the dispensing system shown in  FIG. 1 , according to the embodiments of the subject invention. 
         FIG. 3  is a close-up, partial cross sectional view of the pump and refill unit of the dispensing system shown in  FIGS. 1 and 2 , according to the embodiments of the subject invention. 
         FIG. 4  is a partial cross sectional view of the pump and refill unit showing another embodiment of the subject invention. 
         FIG. 5  is a partial cross sectional view showing yet another embodiment of the pump, reservoir and bladder, according to the embodiments of the subject invention. 
     
    
    
     DETAILED DESCRIPTION 
     A product dispensing system is depicted in  FIG. 1  that dispenses a measured amount of fluid product according to the embodiments of the subject invention. In one exemplary instance, the dispensing system, shown generally at  10 , dispenses hand care products like soap, lotion or sanitizers, although other products may similarly be dispensed from the product dispenser. 
     In the embodiment depicted in  FIG. 1 , the dispensing system  10  includes a base  14 . The base  14  is made of one or more walls  15  constructed to support the components of the dispensing system  10 . Plastic may be used for cost effective manufacturing of the base  14 , as well as other components of the system. A fluid reservoir  26  is mounted to the base in an inverted fashion and includes a pump for dispensing product in a manner known in the art. At a rear side  16  of the base  14 , a mounting bracket is included for attaching the dispenser to a table, IV pole (Intravenous pole), dispenser stand or other supporting structure, none of which are shown in the figures. The mounting bracket may be modular in design, which is to say that the mounting bracket may be detached from the base  14  and replaced with another type of mounting bracket. In this way, the dispensing system may be selectively attached to different types of supporting structures. 
     As mentioned, the base  14  is designed to securely receive the fluid reservoir  26 . The walls  15  of the base  14  may be constructed to form a concave region  20  at an upper end of the dispensing system  10 . Structural components, not shown, receive and lock the reservoir  26  in place during use. A latch  30  is included to release the fluid reservoir when service is required. 
     Before installation into the base  14 , the reservoir is fitted with a pump  51  (shown in  FIG. 2 ). The pump is engaged by an assembly of linkages and driven by a motor, not shown, for actuating the pump and dispensing the product. Batteries may be stored onboard the dispensing system  10  to provide power for actuating the motor. For dispersing fluid product in a desired manner, a nozzle  28  is attached to an outlet of the pump. 
     With continued reference to  FIG. 1 , the base  14  may include a spine  34  or back plate  34  extending downwardly from the base  14 . In one embodiment, the spine  34  is integrally fashioned with the base  14 . However, other embodiments are contemplated where the spine  34  may be fastened to the base  14 . A drip plate  38  extends from the distal end of the spine  34  and protrudes outward at an angle of approximately 90 degrees, although any acute angle may be chosen. The drip plate  38  is thus positioned at an elevation beneath the pump, and more specifically beneath the nozzle. Persons of skill in the art will understand that the drip plate  38  will capture residual product that may drip from the nozzle during or after use. Accordingly, the drip plate  38  may be constructed with a concave center  40  to catch fluid product until it evaporates or is cleaned by service personnel. 
     In one embodiment, the batteries (not shown) may be housed in the body of the drip plate  38 . Conductors (also not shown) may be routed from the battery cavity up to the motor located in the base  14 . It follows that the conductors run to the motor through the spine  34 . In other embodiments, electronic circuitry, e.g. circuit boards, used by the dispensing system  10  may also be housed in the base  14  or spine  34 . It is expressly noted here that other configurations of dispenser housing may be employed that do not include a spine  34  or drip plate  38 . In these embodiments, the control circuitry as well as the batteries may be housed in the base  14 . All such variations are to be construed as falling within the scope of coverage of the embodiments of the subject invention. 
     Still referencing  FIG. 1 , the product dispensing system  10  may be activated without touching the base  14  or any component of the system. Accordingly, the “touch-free” system may include one or more sensors  42  that detect motion beneath the nozzle. In one exemplary embodiment, the sensors  42  use IR (infrared) technology, which may be installed on an underside of the base  14 . To avoid accidental activation, the sensor&#39;s field of detection may be particularly oriented to detect motion only within a specific region between the base  14  and the drip plate  38 . Other types of sensors and/or configurations of sensors may be chosen without departing from the intended scope of coverage of the embodiments of the subject invention. 
     Other modes of operation are considered where the dispensing system  10  is manually activated. A push-bar or lever (not shown in the figures), may be moveably connected to the base  14  of the dispensing system  10 . In one particular embodiment, the push-bar may pivot to directly contact the actuating components of the pump  51 . Alternatively, the push-bar may translate to engage a linkage that actuates the pump  51 . In operation, the user physically depresses the push-bar. Force from the user&#39;s hand is translated to actuate the pump  51 . Accordingly, the need for a motor or other electrically powered actuator is eliminated, as well as the need for motion sensors. 
     With reference now to  FIG. 2 , the fluid reservoir  26  is generally enclosed for storing a predetermined quantity of fluid product in a reservoir area  32 . An aperture is included through which fluid egresses from the reservoir  26 . The aperture may protrude outwardly from an end of the fluid reservoir  26  and may comprise externally fashioned threads  46 , shown in  FIG. 4 , designed to receive and hold a cap  50  in place once assembled. It follows that the cap  50  includes matching threads  52  that interconnect with threads  46 . In one particular embodiment, the reservoir  26  may be constructed via a blow-molding process, although other thermoforming processes may be used as chosen with sound judgment as known by persons of ordinary skill in the art. The reservoir  26 , which may be a replaceable refill reservoir, can be constructed from rigid or semi-rigid polymeric material, as discussed below. Accordingly, as fluid product flows out of the reservoir  26 , the walls  31  of the container will substantially maintain its original shape. 
     With continued reference to  FIG. 2  and now also to  FIG. 3 , the pump  51 , as introduced above, fluidly connects to the aperture of the fluid reservoir  26 . By fluidly connects it is meant that the inlet  55  of the pump  51  is positioned to receive fluid product stored in the reservoir area  32 . As such, the pump  51  is juxtaposed to the aperture or extends through the aperture into the fluid reservoir  26  and may be secured in place by the cap  50 . In one particular embodiment, the pump  51  comprises a pump chamber  57 . At one end of the pump chamber  57 , a valve  58  is positioned to allow fluid flow in only one direction, namely from the reservoir area  32  into the pump chamber  57 . The valve  58  may comprise a check valve  58   a . At the distal end of the pump chamber  57 , another valve  59  is included that similarly allows fluid flow in only one direction, and which connects to the nozzle  28 . A piston reciprocates within the pump chamber  57  in first and second directions. The piston is sealed within the pump chamber  57  so that fluid product enters and exits only through the valves  58 ,  59 . Skilled artisans will understand that when the piston is moved in a first direction, fluid is drawn into the pump chamber  57  from the reservoir area  32  because of negative vacuum pressure created by displacement of the piston. Conversely, movement of the piston in the second direction will pressurize the fluid and force it out of the chamber  57  through the nozzle  28 . Of course, fluid is prevented from flowing back into the reservoir area  32  because of valve  58 . No further explanation about the construction and operation of the pump will be offered at this time. 
     It is expressly noted here that the pump  51  may be integrally fashioned with the cap  50 . However, alternative embodiments are contemplated where the pump  51  comprises a separate component that installs with the cap  50  onto the fluid reservoir  26 . In either case, once securely installed, a fluid tight connection is made between the aperture of the fluid reservoir  26  and the pump/cap assembly. 
     With continued reference to  FIG. 2 , a validation key  60  or tag may be implemented between fluid reservoir  26  and dispensing system  10  for validating the contents of the fluid reservoir  26 . In one particular embodiment, the cap  50  includes the validation key  60 . The key  60  may comprise an RFID (Radio Frequency Identification) tag, which may be either passive or active. A corresponding interrogator, not shown, may be mounted within the base  14 . Accordingly, when the fluid reservoir  26  is installed onto the base  14 , the interrogator will automatically “ping” the electronic key  60  to verify that the correct fluid reservoir  26  is being used. If an incorrect fluid reservoir is installed, a control system will disable operation of the dispenser  10 . Alternative types of validation keys are contemplated where the cap  50  includes an electrically conductive coil, not shown in the figures. The coil may be constructed having a predetermined impedance or electrical signature. When the fluid reservoir  26  is installed onto the base  14 , the coil is communicated with the controller which may sense or measure the impedance for use in validating the fluid reservoir  26 . Skilled artisans will appreciate that other locations for and other forms of validating keys  60  may be used, like for example keyed mechanical fittings or optical sensor systems. Still, any manner of ensuring that the dispensing system  10  works only with an authorized fluid reservoir  26  may be chosen as is consistent with the subject invention described herein. 
     Referring again to  FIG. 3 , the fluid reservoir  26  may include one or more air passageways  63  that allow ambient air to enter a region within the reservoir area  32 . In one particular embodiment, the air passageways  63  may be incorporated into the structure encasing the pump  51  and/or cap  50 . More specifically, the air passageways  63  comprise channels  65  that run adjacent to the pump chamber  57 . The channels  65  terminate at orifices  68 , which connect the channels  65  to the internal region within the reservoir area  32 . The quantity and cross-sectional configuration of orifices  68  may vary as is needed for allowing a particular volume of ambient air to flow into the internal region of the reservoir area  32  as is appropriate for use with a particular output capacity of pump  51 . Notably, the orifices  68  have a smaller cross-sectional area than the channels  65 . However, any suitable ratio of cross-sectional areas of the orifices and the channels may be selected. While the embodiments described herein relate to air passageways formed within the structure of the pump and/or reservoir cap, it is to be understood that air passageways  63  may be incorporated into other portions of the fluid reservoir like for example, but not limited to, the walls  31  of the reservoir  26 . 
     A membrane or bladder  70  is connected that surrounds and isolates the orifices  68  from direct contact with the fluid contained in a reservoir area  32 . As such, fluid contained in the reservoir  26  cannot egress or leak through the orifices  68 . Moreover, air flowing into internal region of the reservoir area  32  (as will be described further below) is prevented from contacting the fluid product thereby maintaining the sanitary seal of the fluid reservoir  26 . 
     The bladder  70  may be constructed from pliable material, which can collapse upon itself or expand when air, i.e. air pressure or atmospheric air, is introduced into the bladder. In one embodiment, the bladder  70  is constructed from polymeric material, which may be a thermoplastic polymer. More specifically, the material comprising the bladder  70  may be comprised of a thermoset material. However any type of material that allows the bladder  70  to adjust its volume may be used as is consistent with the embodiments described herein. 
     The bladder material may have a relatively high elasticity. A bladder  70  constructed from this type of material stretches to expand when air is introduced into its interior and contracts to its original shape when air is relieved from the system. It will be realized that elastomeric material exerts an element of pressure on the air contained within the bladder  70  which is in addition to the pressure exerted by the amount of fluid remaining in the reservoir  26 . 
     In an alternative embodiment, the bladder  70  may be constructed from pliable material having a relatively low elasticity. In this instance, the walls of the bladder  70  do not substantially stretch when filled with air but rather just unfurl or straighten out. Absent air in the bladder  70 , the walls simply fold upon themselves. In this instance, the walls of the bladder  70  expand and retract only as a function of the head pressure within the reservoir area  32 . Still, with either type of material the volume of the bladder changes in response to the amount of fluid remaining in the reservoir area  32 . 
     Still focusing on  FIG. 3 , the bladder  70  may be curved having a spherical or oval cross-sectional configuration. Additionally, the bladder  70  may include an opening at an end portion thereof. From the aforementioned, it will be readily seen that the opening of the bladder may be configured to cover that portion of the structure containing the orifices  68 . In order to receive and hold the bladder  70  in place, the structure containing the orifices  68 , hereafter referred to as the bladder receiving portion  78 , may include a raised lip or recessed groove onto which the peripheral edge of the opening of the bladder  70  may be installed. A clamping mechanism  73  applied to the interface of the bladder and the underlying rigid structure ensures a fluid tight seal there between. In one embodiment, the clamping mechanism  73  may comprise a locking ring  74 . In other embodiments, the clamping mechanism  73  may comprise an elastic band, not shown. However, other means of securing the bladder  70  to the structure containing the orifices  68  may be selected without departing from the intended scope of coverage of the embodiments of the subject invention. 
     It is noted here that other configurations of the bladder receiving portion  78  may be employed without limiting the scope of the claimed invention. Other embodiments may comprise a bladder receiving portion  78  that has a substantially smooth outer surface or alternatively a rippled or an uneven outer surface. Still other embodiments are contemplated where the opening of the bladder  70  is positioned and secured to an inner or recessed surface of the bladder receiving portion  78 . 
     In one method of assembling the fluid reservoir  26 , the bladder  70  may be initially installed onto the bladder receiving portion  78  of the pump  51  and cap  50 . In one embodiment, the orifices  68  are disposed at a distal end of the pump  51 . As such, bladder  70  may be juxtaposed to the distal end of the pump  51  and secured thereto by way of the clamping mechanism  73 . Separately, the reservoir  26  may be filled with fluid product. Once the bladder  70  has been installed and the reservoir has been filled, the pump/bladder assembly may be inserted into the reservoir area  32 , where the entire assembly is secured in place by the cap  50  or by other means chosen with the sound judgment of persons of skill in the art. 
     Skilled artisans will readily see that as the pump  51  is actuated, fluid product will be dispensed through the nozzle  28  and as a result vacuum pressure within the walls of the reservoir  26  will increase. As vacuum pressure increases, ambient air will automatically flow into the bladder  70  expanding its volume thereby equalizing the pressure within the reservoir  26 . Consequently, less energy will be needed to actuate the pump  51 , which maximizes the useful life of the batteries. 
     With reference now to  FIG. 4 , an alternative configuration of the bladder will now be described. In this embodiment, bladder  70   a  is shown and described herein as having side walls that expand and collapse in a predefined manner. Specifically, the side walls of the bladder  70   a  include pleats  71   a  that cause the height of the bladder to expand and retract uniformly. Accordingly, the bladder  70   a  can be constructed from any material suitable for forming the pleats  71   a . When ambient air is drawn into the interior of the bladder  70   a  (in response to fluid product being pumped from the reservoir area), the height of the bladder  70   a  will change, i.e. increase, but the circumference of the bladder will remain substantially the same. In this manner, fluid product will be displaced uniformly near the walls of the reservoir  26  making it easier to see how much fluid is remaining in the reservoir  26 . Still, other configurations for the bladder that uniformly displaced fluid product may be employed. All such variations are to be construed as falling within the scope of coverage of the embodiments of the subject invention. 
     With reference now to  FIG. 5 , it is noteworthy to mention that the bladder  70 ,  70   a  and orifice  63  may be separated from the pump. While the embodiments shown thus far depict the bladder  70 ,  70   a  and orifices  68  incorporated into the pump or pump housing, the bladder  70 ,  70   a  and orifices  68  may be incorporated into another portion of the reservoir  26 .  FIG. 5  shows one exemplary configuration of an orifice  68  fashioned in a side portion, i.e. side wall, of the reservoir  26 . A lip may be formed internally around the orifice  68 , onto which the inlet of the bladder  70 ,  70   a  may be fixedly attached via locking ring  74  or by other means. Alternatively, the bladder  70 ,  70   a  and orifice(s)  68  may be distally positioned opposite to the location of the pump  51 . However, it is to be construed that the bladder  70 ,  70   a  and corresponding orifice(s)  68  may be disposed anywhere within the reservoir as is appropriate for use to vent the reservoir  26 . 
     The dispensing system  10  may further include a control system (mentioned above) comprising one or more electronic circuits, not shown, for controlling the operation of the dispensing system  10 . The electronic circuitry may reside on a printed circuit board and received in a suitable enclosure, not shown. Energy may be supply from the batteries to power the control system. In one embodiment, digital electronic circuitry is included in the control system, which functions to output signals used to control operation of various components of the dispensing system  10 , like for example operation of the motor, not shown. The digital electronic circuitry may also function to receive input signals from the electronic validation key  60  and onboard sensors  42 . During maintenance of the dispenser  10 , service personnel may detach the existing fluid reservoir  26  from the base  14  and replace it with a new sanitary fluid reservoir. Once installed, the control system will check the signal received by the interrogator to ensure that the correct refill unit has been installed. Upon verification, the control system will enable the motor to actuate the pump  51  when activated by the user. 
     Having illustrated and described the principles of the dispensing system in one or more embodiments, it should be readily apparent to those skilled in the art that the invention can be modified in arrangement and detail without departing from such principles.