Automatic soap dispenser

Information

  • Patent Grant
  • 6209752
  • Patent Number
    6,209,752
  • Date Filed
    Wednesday, March 10, 1999
    25 years ago
  • Date Issued
    Tuesday, April 3, 2001
    23 years ago
Abstract
A soap dispenser of the type in which a disposable soap cartridge is maintained in a wall-mounted housing is configured for automatic operation. A quantity of soap is dispensed when a user's hand, detected by optical reflectivity, is located proximate to the dispenser housing. In order to prevent reliance on AC power, the device is powered from self-contained batteries and/or solar power cells. In one embodiment, a generally flat battery may be included with the disposable soap cartridge such that a new battery is provided each time the cartridge is replaced. Alternatively, or in addition, solar panels may be located on the dispenser housing. The solar panels may be used to charge energy storage components located in the housing, such as a rechargeable battery or storage capacitors. The solar panels are preferably of a type which is suitably efficient in fluorescent (blue) lighting conditions.
Description




BACKGROUND OF THE INVENTION




The present invention relates generally to dispensers for liquid soap and other viscous materials. More particularly, the invention relates to devices that automatically detect the presence of a user's hand and dispense a predetermined quantity of the viscous material.




Wall-mounted dispensers for liquid soap or other viscous material, such as hand lotion, are widely used in public and commercial buildings. Often, the dispenser will be constructed having a support base attached to the wall. A pivotal cover is closable on the base to define a housing in which components of the dispenser are contained. The viscous material is located in a storage bag or the like provided as part of a disposable cartridge located in the housing's interior. The disposable cartridge includes a tube forming a peristaltic pump through which the viscous material is dispensed.




Many dispensers of the prior art operate manually, wherein a lever is moved by the user when a quantity of the viscous material is desired. Alternatively, the dispenser may be adapted for automatic operation. In devices of this type, a photoelectric detection circuit is typically provided to sense the presence of a user's hand near the dispenser. When the hand is detected, the device actuates the peristaltic pump to thereby release a predetermined quantity of the viscous material.




Due to the use of electrical and electromechanical components therein, automatic dispensers require a source of power in order to operate. In some cases, the dispenser may be adapted for AC operation from a conventional wall outlet. Often, however, AC operation has been seen as undesirable, in part because it limits the potential locations at which the dispenser can be installed.




In order to overcome the disadvantages of using AC power, dispensers have been provided that operate from battery power. These dispensers, however, have typically employed general purpose batteries, such as D-cells. Because such batteries are relatively large, the dispenser housing must be appropriately sized. In addition, batteries of this type are often subject to frequent replacement.




SUMMARY OF THE INVENTION




The present invention recognizes and addresses the foregoing disadvantages, and others of prior art constructions and methods. Accordingly, it is an object of the present invention to provide a novel dispenser for viscous material such as liquid soap.




It is a further object of the present invention to provide an automatic dispenser for viscous material having various novel arrangements for providing operational power.




It is a more particular object of the present invention to provide an automatic dispenser for viscous material that employs a compact battery incorporated into the disposable soap cartridge.




It is also a particular object of the present invention to provide an automatic dispenser for viscous material that employs solar power cells to provide primary or supplemental power for operation thereof.




Some of these objects are achieved by a dispenser for automatically dispensing viscous material. The dispenser comprises a base, and a cover movable between an open position and a closed position. The cover and base define a housing for containing components of the dispenser when the cover is in the closed position. A disposable cartridge is also provided, having a reservoir of viscous material to be dispensed through a dispensing tube. The disposable cartridge further includes at least one generally flat battery.




The dispenser also includes a mechanical actuator, configured to engage the dispensing tube of the disposable cartridge such that a quantity of the viscous material is dispensed therethrough. Detection circuitry is operative to detect presence of a user's hand at a predetermined location near the dispenser. A motor is operative in response to the detection circuitry to cause movement of the mechanical actuator.




The generally flat battery will preferably define terminal portions engaged by fixed terminals when the disposable cartridge is inserted in the housing. The fixed terminals, for example, may comprise respective spring elements to facilitate firm engagement against the terminal portions of the generally flat battery. Often, the generally flat battery may be carried on a side surface of the disposable cartridge.




In some exemplary embodiments, the dispenser may further comprise at least one solar power cell operative to supplement power supplied by the generally flat battery. For example, the solar power cell may be operative to charge at least one supplemental power storage component, such as one or more batteries or storage capacitors, located in the housing. The circuitry of the dispenser may be configured such that substantially all power to operate the motor is derived from the generally flat battery of the disposable cartridge and substantially all power to operate the detection circuitry is derived from the supplemental power storage component.




Other objects of the invention are achieved by a dispenser for automatically dispensing viscous material. The dispenser comprises a base, and a cover movable between an open position and a closed position. The cover and base define a housing for containing components of the dispenser when the cover is in the closed position. A disposable cartridge is also provided, having a reservoir of viscous material to be dispensed through a dispensing tube.




The dispenser also includes a mechanical actuator, configured to engage the dispensing tube of the disposable cartridge to cause a quantity of the viscous material to be dispensed therethrough. Detection circuitry is operative to detect presence of a user's hand at a predetermined location near the dispenser. A motor is operative in response to the detection circuitry to cause movement of the mechanical actuator.




At least one solar power cell, which may comprise a solar panel mounted on the cover, is also provided to charge at least one supplemental power storage component. Preferably, the solar power cell may be of the type which is suitably efficient in conditions of fluorescent lighting. The supplemental power storage component, located in the housing, supplies power to at least the detection circuitry of the dispenser.




Often, the supplemental power storage component may comprise at least one rechargeable battery. The rechargeable battery may comprise a nonmemory-type battery, such as a nickel-metal-hydride battery or a lithium ion battery. In some embodiments, the supplemental power storage component may comprise at least one storage capacitor.




Additional objects of the invention are achieved by a dispenser for automatically dispensing viscous material. The dispenser comprises a wall-mounted housing in which a disposable cartridge having a reservoir of viscous material to be dispensed is located. The disposable cartridge further includes a generally flat battery, defining terminal portions engaged by fixed terminals.




The dispenser further comprises a mechanical actuator operative to cause a quantity of the viscous material to be dispensed from the reservoir. Detection circuitry, including a light emitter and a light sensitive receiver, is operative to detect presence of a user's hand at a predetermined location near the dispenser. A motor is operative in response to the detection circuitry to cause movement of the mechanical actuator.




At least one solar power cell is located on the housing to receive ambient light. The solar cell charges at least one supplemental power storage component located in the housing for supplying power to at least the detection circuitry. Often, the supplemental power storage component may comprise at least one rechargeable battery, such as a nonmemory-type battery. In some cases, the supplemental power storage component may comprise at least one storage capacitor.




Still further objects of the present invention are achieved by a disposable cartridge for use in a wall-mounted dispenser device of the type operative to automatically dispense viscous material such as liquid soap by a discrete quantity with each actuation. The cartridge comprises a cartridge box having a top, bottom and a plurality of sides. A flexible bag, located in the box, contains a supply of the viscous material. A peristaltic pump in fluid communication with the flexible bag includes a tube extending away from the box. The tube is compressible to cause the discrete quantity of viscous material to be dispensed therethrough. The cartridge further includes a generally flat battery defining terminal portions engaged by fixed terminals when the disposable cartridge is inserted in the dispenser.




Still further objects of the present invention are achieved by a dispenser for automatically dispensing viscous material. The dispenser comprises a base, and a cover movable between an open position and a closed position. The cover and base define a housing for containing components of the dispenser when the cover is in the closed position. A disposable cartridge is also provided, having a reservoir of viscous material to be dispensed through a dispensing tube.




The dispenser also includes a mechanical actuator, configured to engage the dispensing tube of the disposable cartridge such that a quantity of the viscous material is dispensed therethrough. Detection circuitry is operative to detect presence of a user's hand at a location near the dispenser. A motor, operative in response to the detection circuitry, causes movement of the mechanical actuator.




In this case, the motor and detection circuitry of the dispenser are configured such that together they require no more than about 350 μA of current during operation. At least one solar power cell is provided having sufficient output under fluorescent lighting conditions to substantially completely power the detection circuitry and the motor.




Other objects, features and aspects of the present invention are discussed in greater detail below.











BRIEF DESCRIPTION OF THE DRAWINGS




A full and enabling disclosure of the present invention, including the best mode thereof, to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, including reference to the accompanying figures, in which:





FIG. 1

is a perspective view of an automatic dispenser of the present invention as it may appear in use;





FIG. 2

is a side elevation of the dispenser of

FIG. 1

with the cover in the open position;





FIG. 3

is an enlarged view, partially in section, showing certain internal components of the dispenser of

FIG. 1

;





FIG. 4

is a view as taken along line


4





4


of

FIG. 3

;





FIG. 5

is a view as taken along line


5





5


of

FIG. 3

;





FIG. 6

is a side elevation of a disposable soap cartridge of the present invention, utilized in the dispenser of

FIG. 1

;





FIG. 7

is a back elevational view of the disposable soap cartridge of

FIG. 6

showing details of the battery and terminals thereof;





FIG. 8

is an enlarged diagrammatic view showing the manner in which a disposable cartridge is inserted into the dispenser housing such that electrical contact with the cartridge battery is achieved;





FIG. 9

is a block diagram showing various functional components that may be employed in the dispenser of

FIG. 1

;





FIG. 10

is a schematic diagram of one preferred circuit arrangement that may be used to implement the functional components shown in

FIG. 9

;





FIG. 11

is a perspective view of a modified automatic dispenser in accordance with the present invention, including solar power cells installed on the dispenser housing;





FIG. 12

is a block diagram showing various functional components that may be employed in one embodiment of a dispenser including solar power cells as shown in

FIG. 11

; and





FIG. 13

is a block diagram showing various functional components that may be employed in another embodiment of a dispenser including solar power cells as shown in FIG.


11


.











Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention.




DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS




It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only, and is not intended as limiting the broader aspects of the present invention, which broader aspects are embodied in the exemplary constructions.





FIG. 1

illustrates a dispenser


10


of the present invention as it may appear when installed on a wall or other vertical surface. Dispenser


10


operates automatically to meter a predetermined amount of soap, lotion or other viscous material into the hand


12


of a user. Preferably, the user is not required to touch the dispenser in order to cause the viscous material to be dispensed. Instead, dispenser


10


contains proximity circuitry operative to determine when hand


12


is in the correct position to receive the viscous material.




Referring now to

FIG. 2

, dispenser


10


is constructed having a base


14


configured for attachment to the wall or other vertical surface. A cover


16


is pivotally attached for movement between an open position (as shown in

FIG. 2

) and a closed position (as shown in FIG.


1


). In the closed position, base


14


and cover


16


form a housing in which various other components of dispenser


10


are contained.




Among the other components within dispenser


10


is a disposable cartridge


18


containing a supply of the viscous material to be dispensed. Cartridge


18


includes a box


20


, typically formed of paperboard, in which a flexible bag


22


is located. Bag


22


serves as the reservoir of viscous material to be dispensed through a peristaltic pump assembly


24


. As shown, pump assembly


24


includes an elongate tube


26


extending away from box


20


. Tube


26


is compressible, by operation of a mechanical actuator


28


, to meter the predetermined quantity of viscous material. Preferably, pump assembly


24


will include one or more check valves to ensure flow of the viscous material in the desired direction.




It will be appreciated that various types of mechanisms may be utilized to compress tube


26


. As shown most clearly in

FIGS. 3 through 4

, however, mechanical actuator


28


comprises an upstanding element


30


having a suitable engaging portion


32


located thereon. As shown, upstanding element


30


is pivotally connected to a shelf


34


integrally extending out from base


14


. Shelf


34


defines a slot


36


in which a fitting


38


(FIG.


2


), located at the end of tube


26


, is received.




Shelf


34


supports an internal compartment


40


in which various elements used to effect movement of mechanical actuator


28


are located. In this case, a drive motor


42


includes a worm gear


44


located on its shaft. Rotation of worm gear


44


causes movement of an elliptical cam


46


through gear stages


48


,


50


and


52


. The shaft


56


on which cam


46


and gear


54


are mounted also carries a “time out” cam


58


. Cam


58


, in turn, engages a roller


60


carried by a microswitch device


62


.




Microswitch


62


functions to shut off operation of motor


42


after cam


46


is rotated back to its “at rest” position. Preferably, microswitch


62


is mounted to a circuit board


64


which carries various electronic components used to detect the presence of a user's hand as well as to control operation of motor


42


. In presently preferred embodiments, the detection circuitry utilizes the optical reflectivity of the user's hand to detect its presence near dispenser


10


. It should be distinctly understood, however, that various types of active and passive proximity detection circuits may be utilized for this purpose.




In the illustrated embodiment, a suitable light source, such as a light-emitting diode (LED)


66


, which will often operate in wavelengths other than visible light, emits a light signal. When the user's hand is near, this light signal is reflected back to a light sensitive receiver


68


. Preferably, the circuitry will be adapted to detect the user's hand up to a range of about three to four inches, irrespective of the skin tone of the user. LED


66


and detector


68


are electrically connected to circuitry contained on circuit board


64


.




Referring now to

FIGS. 5-8

, dispenser


10


is constructed to obviate the need for AC power, as well as relatively large batteries as have often been used in the past. According to one aspect of the invention, the need for battery replacement is largely eliminated by incorporating the battery into disposable cartridge


18


. Because a new battery is provided each time cartridge


18


is replaced, the need to frequently monitor the condition of the batteries is eliminated.




In the illustrated embodiment, cartridge


18


includes a generally flat battery


70


attached to the back side of box


20


. As shown, battery


70


defines a pair of opposite polarity terminals


72


and


74


on its outwardly directed surface. When box


20


is seated on shelf


76


of base


14


, battery terminals


72


and


74


are engaged by corresponding fixed terminals


78


and


80


.




As shown, fixed terminals


78


and


80


may include springs to facilitate good electrical contact with the battery terminals. Alternatively, the fixed terminals may be made of spring steel configured to firmly engage the battery terminals. Particularly in this latter case, it may be desirable to form a suitable slot structure in base


14


to slidably receive the flat battery as disposable cartridge


18


is set in place. Because the battery itself will be captured in the slot, good contact between the battery terminals and the fixed terminals will be ensured.




If low power actuation circuitry is used, the battery of cartridge


18


can be made relatively small while still permitting the entire contents of flexible bag


22


to be dispensed. In this regard, it has been found that commercially available batteries may effectively dispense the entire contents of a typical 500 ml replacement cartridge. In one preferred arrangement, the detection circuitry and motor may be adapted to consume no more than about 350 μA of current during their operation. An experiment using liquid soap as the viscous material to be dispensed showed that a Polaroid Polapulse 6-Volt P100 battery, rated to deliver 1 mA for 264 hr (264 mAH), may deliver at least 720 ml of soap in 1 ml increments prior to battery failure.




Various functional sections of the circuitry employed in a preferred embodiment of dispenser


10


are illustrated in FIG.


9


. As indicated at


82


, appropriate circuitry is provided in order to condition electrical power for use by other components. In this case, power circuitry


82


supplies a first output V


cc


directly to motor


42


. The voltage V


cc


is, in this case, essentially a direct output from battery


70


. A filtered voltage V


bb


is provided by power circuitry


82


to the remaining electrical components.




The remaining functional components include transmitter circuitry


84


, which causes emission of light by diode


66


(FIG.


3


). As noted above, this light is then received at detector


68


(

FIG. 3

) if reflected by a hand. Detector


68


is included within receiver circuitry


86


, which provides a responsive signal to motor timer circuitry


88


. Upon receipt of a momentary signal from receiver circuitry


86


, motor timer circuitry


88


will provide a long duration signal to motor


42


. As a result, motor


42


will operate for a time sufficient to dispense the desired quantity of viscous material.





FIG. 10

illustrates a preferred circuit arrangement constructed in accordance with the functional relationships illustrated in FIG.


9


. The structure and operation of the circuitry shown in

FIG. 10

will be apparent to one skilled in the art. It should be noted, however, that the integrated circuits (ICs) indicated at


90


and


92


may be respective timer sections of a single RC 556 dual timer chip.




It will be appreciated that the size, and thus the cost, of the battery included within the disposable cartridge can be further reduced if supplemental power is provided to the circuitry within the dispenser. Thus,

FIG. 11

illustrates a modified dispenser


94


in which a solar panel


96


is mounted to the exterior of the housing. Because dispenser


94


will often be used in public bathrooms and other such locations, it is desirable that solar panel


96


have sufficient efficiency in the presence of fluorescent (blue) light. In this regard, certain solar cells are known to provide adequate levels of efficiency in fluorescent light, in addition to also having adequate efficiency in sunlight and incandescent lighting. For example, one such cell, available from Entech Corporation of Dallas, Tex., produces 7.1 VDC at a maximum current output of 174.8 mA.





FIG. 12

illustrates one arrangement whereby solar power can be used to supplement power supplied by the disposable battery. In this case, the power supply is bifurcated such that substantially all of the power used to operate motor


98


is derived from the cartridge battery power circuit indicated at


100


. Substantially all of the power to operate the remaining portions of the overall circuit is derived from solar panel


96


.




In some cases, it may be feasible to power the various circuit components directly from the output of solar panel


96


. Often, however, it will be desirable to provide one or more storage components at which charge supplied by solar panel


96


is stored for later use. For example, solar panel


96


may not provide a sufficient level of current at all times, but may provide, on average, a sufficient level of current from which to operate the desired circuitry.




In one preferred embodiment, the output of solar panel


96


is used to maintain a charge, through charging circuitry


102


, on one or more rechargeable batteries


104


. The rechargeable batteries are preferably of a non-memory type, such as nickel metal hydride or lithium ion batteries. In addition to or in lieu of rechargeable batteries


104


, the output of solar panel


96


may be used to maintain a charge across storage capacitors


106


having a sufficient capacitance value.




As shown, power derived from solar panel


96


is used to operate transmitter circuitry


108


, receiver circuitry


110


, and motor timer circuitry


112


. As described above with respect to

FIG. 9

, transmitter circuitry


108


functions to emit a light signal which is detected by receiver circuitry


110


when a user's hand is present. Receiver circuitry


110


supplies a trigger signal to motor timer circuitry


112


, which then provides an actuation signal of relatively long duration to motor


98


.





FIG. 13

illustrates an alternative embodiment wherein all power for operation of the device is derived from solar panel


96


. As can be seen, components analogous to those of the embodiment in

FIG. 12

are shown by the same reference number. The operation of this embodiment will be apparent to one skilled in the art from the above discussion.




It can thus be seen that the present invention provides a novel dispenser apparatus in furtherance of the noted objects. While presently preferred embodiments of the invention have been shown and described, it should be understood that various modifications and variations may be made thereto by those of ordinary skill in the art. In addition, it should be understood that aspects of the various embodiments may be interchanged both in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and it is not intended to be limitative of the spirit and scope of the invention so further set forth in the following claims.



Claims
  • 1. A dispenser for automatically dispensing viscous material, said dispenser comprising:a base; a cover movable between an open position and a closed position, said cover and said base defining a housing for containing components of said dispenser when said cover is in the closed position; a disposable cartridge having a reservoir of viscous material to be dispensed through a dispensing tube, said disposable cartridge further including at least one generally flat battery; a mechanical actuator configured to engage said dispensing tube of said disposable cartridge to cause a quantity of said viscous material to be dispensed therethrough; detection circuitry operative to detect presence of a user's hand at a predetermined location near said dispenser; and a motor receiving operational power from said generally flat battery of said disposable cartridge, said motor operative in response to said detection circuitry to cause movement of said mechanical actuator.
  • 2. A dispenser as set forth in claim 1, said generally flat battery defines terminal portions engaged by fixed terminals when said disposable cartridge is inserted in said housing.
  • 3. A dispenser as set forth in claim 2, wherein said fixed terminals comprise respective spring elements to facilitate firm engagement against said terminal portions of said generally flat battery.
  • 4. A dispenser as set forth in claim 2, wherein said generally flat battery is carried on a side surface of said disposable cartridge.
  • 5. A dispenser as set forth in claim 1, further comprising at least one solar power cell operative to supplement power supplied by said generally flat battery.
  • 6. A dispenser as set forth in claim 5, wherein said solar power cell is operative to charge at least one supplemental power storage component located in said housing.
  • 7. A dispenser as set forth in claim 6, wherein said supplemental power storage component comprises at least one rechargeable battery.
  • 8. A dispenser as set forth in claim 6, wherein said at least one supplemental power storage component comprises at least one storage capacitor.
  • 9. A dispenser as set forth in claim 6, wherein substantially all power to operate said motor is derived from said generally flat battery of said disposable cartridge and substantially all power to operate said detection circuitry is derived from said supplemental power storage component.
  • 10. A dispenser as set forth in claim 5, wherein said at least one solar power cell comprises a solar panel mounted on said cover.
  • 11. A dispenser for automatically dispensing viscous material, said dispenser comprising:a base; a cover movable between an open position and a closed position, said cover and said base defining a housing for containing components of said dispenser when said cover is in the closed position; a disposable cartridge having a reservoir of viscous material to be dispensed through a dispensing tube, said disposable cartridge further including a generally flat battery defining terminal portions engaged by fixed terminals when said disposable cartridge is inserted in said housing; a mechanical actuator configured to engage said dispensing tube of said disposable cartridge to cause a quantity of said viscous material to be dispensed therethrough; detection circuitry operative to detect presence of a user's hand at a predetermined location near said dispenser; a motor operative in response to said detection circuitry to cause movement of said mechanical actuator; at least one solar power cell; and at least one supplemental power storage component located in said housing and being charged by said solar power cell; wherein substantially all power to operate said motor is derived from said generally flat battery of said disposable cartridge and substantially all power to operate said detection circuitry is derived from said supplemental power storage component.
  • 12. A dispensed as set forth in claim 11, wherein said supplemental power storage component comprises at least one rechargeable battery.
  • 13. A dispenser as set forth in claim 12, wherein said rechargeable battery comprises a nonmemory-type battery.
  • 14. A dispenser as set forth in claim 13, wherein said nonmemory-type battery is selected from a group consisting of nickel-metal-hydride batteries or lithium ion batteries.
  • 15. A dispenser as set forth in claim 11, wherein said at least one supplemental power storage component comprises at least one storage capacitor.
  • 16. A dispenser as set forth in claim 11, wherein said at least one solar power cell comprises a solar panel mounted on said cover.
  • 17. A dispenser as set forth in claim 11, wherein said solar power cell is adapted to be suitably efficient in conditions of fluorescent lighting.
  • 18. A dispenser for automatically dispensing viscous material, said dispenser comprising:a wall-mounted housing; a disposable cartridge having a reservoir of viscous material to be dispensed, said disposable cartridge further including a generally flat battery defining terminal portions engaged by fixed terminals when said disposable cartridge is inserted in said housing; a mechanical actuator operative to cause a quantity of said viscous material to be dispensed from said reservoir; detection circuitry including an light emitter and a light sensitive receiver, said detection circuitry operative to detect presence of a user's hand at a predetermined location near said dispenser; a motor operative in response to said detection circuity to cause movement of said mechanical actuator; at least one solar power cell located on said housing to receive ambient light; and at least one supplemental power storage component located in said housing and being charged by said solar power cell; wherein substantially all power to operate said motor is derived from said generally flat battery of said disposable cartridge and substantially all power to operate said detection circuitry is derived from said supplemental power storage component.
  • 19. A dispenser as set forth in claim 18, wherein said supplemental power storage component comprises at least one rechargeable battery.
  • 20. A dispenser as set forth in claim 19, wherein said rechargeable battery comprises a nonmemory-type battery.
  • 21. A dispenser as set forth in claim 20, wherein said nonmemory-type battery is selected from a group consisting of nickel-metal-hydride batteries or lithium ion batteries.
  • 22. A dispenser as set forth in claim 18, wherein said at least one supplemental power storage component comprises at least one storage capacitor.
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