Patent Publication Number: US-6209752-B1

Title: Automatic soap dispenser

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&#39;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&#39;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&#39;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&#39;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&#39;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&#39;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&#39;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&#39;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&#39;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&#39;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&#39;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&#39;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.