Patent Publication Number: US-11647871-B2

Title: Liquid dispensing units

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This present application is a continuation of U.S. application Ser. No. 15/707,806, filed Sep. 18, 2017, entitled “Liquid Dispensing Units,” which is a divisional of U.S. application Ser. No. 14/661,372, filed Mar. 18, 2015, entitled “Liquid Dispensing Units,” which is a divisional of U.S. application Ser. No. 13/762,265, filed Feb. 7, 2013, entitled “Liquid Dispensing Units,” which claims priority benefit under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 61/596,672, filed Feb. 8, 2012, entitled “Soap Dispensing Units,” and U.S. Provisional Application No. 61/609,213, filed Mar. 9, 2012, entitled “Soap Dispensing Units.” All of the aforementioned applications are hereby incorporated by reference in their entirety. 
    
    
     BACKGROUND 
     Field 
     The present disclosure relates to liquid dispensers, and more particularly, some embodiments relate to electronic liquid dispensers. 
     Description of the Related Art 
     Users of modern public washroom facilities increasingly desire that each of the fixtures in the washroom operate automatically without being touched by the user&#39;s hand. This is important in view of increased user awareness of the degree to which germs and bacteria may be transmitted from one person to another in a public washroom environment. Today, it is not uncommon to find public washrooms with automatic, hands-free operated toilet and urinal units, hand washing faucets, soap dispensers, hand dryers, and door opening mechanisms. This automation allows the user to avoid touching any of the fixtures in the facility, and therefore lessens the opportunity for the transmission of disease-carrying germs or bacteria resulting from manual contact with the fixtures in the washroom. 
     SUMMARY 
     In some embodiments, a liquid dispenser such as a soap dispenser comprises a proximity sensor or a reflective type sensor configured to generate a signal representing the distance between an object and the sensor, and an electronic processor configured to generate an electronic signal to the motor for dispensing a volume of soap that varies depending on the distance between the object and the sensor. 
     In some embodiments, a liquid dispenser comprises a removable cartridge configured to contain a volume of liquid such as soap and a battery in a single disposable unit. The removable cartridge can include attachment members to help attach the cartridge to the pump during use in a manner that permits the cartridge to be removed after the liquid and/or battery is spent. 
     In some embodiments, a disposable cartridge for an electric liquid dispenser comprises a cartridge housing with attachment members configured to removably attach to a pump housing; a reservoir within or attached to the cartridge housing configured to contain a volume of liquid such as soap; a battery within or attached to the cartridge housing configured to provide sufficient electrical energy to power a liquid dispenser for at least the period during which the liquid such as soap contained within the reservoir will be used during normal usage. 
     Certain aspects of this disclosure are directed toward liquid dispensers including a housing, a reservoir, a fluid passage, a pump, a motor, a first sensor, and an electronic processor. The reservoir can be configured to store liquid. The fluid passage can be disposed in the housing and can include an inlet and an outlet. The pump can be disposed in the housing. The pump can include an opening disposed in a pump body, and the opening can be in fluid communication with the reservoir. The pump can be configured to allow air disposed therein to pass through the opening. The motor can be disposed in the housing. The motor can be configured to drive the pump, which can be configured to encourage a flow of liquid from the reservoir into the inlet and out of the outlet of the fluid passage. The first sensor can be configured to generate a signal representing a distance between an object and the first sensor. The electronic processor can be configured to receive the signal from the first sensor and to determine a dispensation volume of the liquid or another variable characteristic of the dispensed liquid, such as the type of liquid to be dispensed (e.g., soap or lotion or sanitizer, or different types or grades of these liquids, etc). In a system in which multiple types of liquid can be dispensed, a plurality of liquid reservoirs and valves can be utilized to control the flow of multiple liquids. The dispensation volume or other liquid characteristic can vary as a function of the distance between the object and the first sensor. The processor can be configured to control the motor to dispense approximately the desired dispensation volume of the liquid. 
     Any of the liquid dispenser features, structures, steps, or processes disclosed in this specification can be included in any embodiments. The motor can be configured to dispense a first volume of fluid when the object is within a first distance from the first sensor and dispense a second volume of fluid when the object is within a second distance from the first sensor. The first volume can be smaller than the second volume, and the first distance can be less than a second distance. The liquid dispenser can include a second sensor configured to generate a signal when the object is within a sensing region of the second sensor. The dispensation volume can be bound by an upper dispensation amount limit. The electronic processor can include one or more subroutines configured to generate an electronic signal to the motor for dispensing the upper dispensation amount limit of the liquid when the object is within the sensing region of the second sensor. The first sensor can be configured to be activated and deactivated. The electronic processor can be configured to deactivate the first sensor for a period of time after the first sensor generates the signal based on the distance between the object and the first sensor, thereby inhibiting the sensor from generating an additional instance of the signal during the period of time. The electronic processor can be configured to calibrate a first distance to correspond to a first volume and calibrate a second distance to correspond to a second volume. The liquid dispenser can include a port configured to connect the liquid dispenser to a computer. The liquid dispenser can include a user input device configured to manually dispense the volume of liquid. 
     Certain aspects of this disclosure are directed toward methods of manufacturing a soap dispenser. In certain aspects, the methods can include forming the soap dispenser. The soap dispenser can include a pump, a motor, a first sensor, and an electronic processor. In certain aspects, the methods can include configuring the first sensor to generate a signal representing a distance between an object and the first sensor. In certain aspects, the methods can include configuring the electronic processor to check for signals generated by the first sensor. In certain aspects, the methods can include configuring the electronic processor to generate a signal to the motor to dispense a volume of soap that varies depending on the distance between the object and the sensor. 
     The method of manufacturing steps disclosed in this specification can be used in any embodiments. Configuring the electronic processor to generate the signal to the motor can include generating a first signal to the motor to dispense a first volume of fluid when the object is within a first distance from the first sensor and generating a second signal to dispense a second volume of fluid when the object is within a second distance from the first sensor. The first volume can be smaller than the second volume, and the first distance can be less than the second distance. The methods can include generating a second signal with a second sensor of the soap pump and receiving the second signal in the processor. The methods can include configuring the electronic processor to generate a signal to the motor to dispense a predetermined volume of soap when the object is detected within a sensing region of a second sensor. The methods can include configuring the electronic processor to deactivate the first sensor for a period of time after the first sensor generates the signal representing the distance between the object and the first sensor. 
     Certain aspects of this disclosure are directed toward liquid dispensers such as soap dispensers having a removable cartridge. The liquid dispenser can include a housing, a fluid passage, a pump, and a motor. The fluid passage, the pump, and the motor can be disposed in the housing. The fluid passage can include an inlet and an outlet. The pump can include an opening disposed in a pump body, and the opening can be in fluid communication with the removable cartridge. The removable cartridge can comprise one or more liquid reservoirs configured to contain at least one liquid such as soap (or multiple liquids in some embodiments with a plurality of reservoirs), and a power source in a single disposable unit. The motor can be configured to a drive the pump to encourage a flow of liquid such as soap from the removable cartridge into the inlet and out of the outlet of the fluid passage. 
     The liquid dispenser features disclosed in this specification can be included in any embodiments. The power source can include a battery. The dispenser can include a removable cartridge capable of engaging a bottom portion of the housing. The pump can include at least two gears. The pump can be positioned near an upper portion of the soap dispenser. The motor can be disposed between the pump and a top surface of the housing. The pump can be configured to discharge liquid such as soap from a pump outlet in a generally vertical pathway. The liquid dispenser can include a user input device configured to manually dispense liquid. The liquid dispenser can include a removable cartridge having an indicator configured to indicate at least one characteristic of the cartridge to the pump. In certain aspects, the at least one characteristic of the cartridge is selected from the group consisting of a brand of the liquid, a viscosity of the liquid, a moisture content of the liquid, a volume of the liquid, the type of liquid or liquids (soap, lotion, sanitizer, etc), and a battery capacity. In certain aspects, at least one output characteristic of the pump can be adjusted based on the at least one characteristic of the cartridge. In certain aspects, the at least one output characteristic is selected from the group consisting of a dispensation volume, a dispensation period, a motor duty cycle, a pumping pressure, and an operational voltage. 
     Certain aspects of this disclosure are directed toward a disposable cartridge for an electric liquid dispenser. The cartridge can include a housing having attachment members configured to removably attach to a pump housing. The cartridge can include a reservoir or reservoirs within or attached to the cartridge housing and configured to contain a volume of liquid such as soap and/or other types of liquid. The reservoir can be configured to contain a volume of liquid such as soap. The volume of liquid can be configured to be about exhausted after a set number of dispensation cycles during normal use of the liquid dispenser. The cartridge can include a battery within or attached to the cartridge housing. The battery can be configured to provide sufficient electrical energy to power a motor of the soap dispenser for about or at least about the set number of dispensation cycles. 
     The features of the disposable cartridge disclosed in this specification can be included in any embodiments. The cartridge can include soap or another type of liquid in the reservoir. The battery can be configured to be exhausted at about the same time as a volume of soap is exhausted. The cartridge can include a one-way valve. The cartridge can include a seal configured to be punctured or otherwise moved or opened when the cartridge housing attaches to the soap pump housing. 
     Certain aspects of this disclosure are directed toward a fluid cartridge for an electrical fluid dispenser. The fluid cartridge can include a disposable housing configured to attach to a pump unit. The cartridge can include a reservoir, an engagement mechanism, and an indicator. The engagement mechanism can be configured to removably attach the housing to the pump unit. The indicator can be configured to indicate at least one characteristic of the cartridge to the pump unit, such as a characteristic regarding the one or more liquids in the one or more reservoirs in the cartridge, the volume of liquid left in one or more reservoirs in the cartridge, the remaining power of the battery in the cartridge, etc. 
     The features of the fluid cartridge disclosed in this specification can be included in any embodiments. The fluid cartridge can include a battery attached to the disposable housing. The at least one characteristic can be selected from the group consisting of a brand of a fluid in the reservoir, a viscosity of the fluid, a moisture content of the fluid, a volume of the fluid, and a battery capacity. The indicator can include a configuration of one or more structures, the configuration representing the at least one characteristic of the cartridge. The indicator can include electronic circuitry configured to produce an electronic signal. The electronic signal can represent the at least one characteristic of the cartridge. The engagement indication element can be configured to indicate that the fluid cartridge is properly engaged with the pump unit. The engagement mechanism can include one or more protrusions configured to be received in a corresponding one or more openings of the pump unit. 
     For purposes of summarizing the disclosure, certain aspects, advantages and features of the inventions have been described herein. It is to be understood that not necessarily any or all such advantages will be achieved in accordance with any or all particular embodiments of the inventions disclosed herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Certain features, aspects, and advantages of the subject matter disclosed herein are described below with reference to the drawings, which are intended to illustrate and not to limit the scope of the disclosure. Various features of different disclosed embodiments can be combined to form additional embodiments, which are part of this disclosure. No structures, features, steps, or processes are essential or critical; any can be omitted in certain embodiments. The drawings comprise the following figures: 
         FIG.  1    schematically illustrates an automatic liquid soap dispenser. 
         FIG.  2    illustrates a front, top, left side perspective view of an embodiment of an automatic liquid soap dispenser. 
         FIG.  3    illustrates a left side elevational view of the liquid soap dispenser of  FIG.  2   . 
         FIG.  4    illustrates a top plan view of the liquid soap dispenser of  FIG.  2   . 
         FIG.  5    illustrates a rear elevational view of the liquid soap dispenser of  FIG.  2   . 
         FIG.  6    illustrates a front, bottom, right side exploded perspective view of the liquid soap dispenser in  FIG.  2   , showing a pump and motor cavity cover member, a battery compartment cover member, and a gasket separated from the main housing thereof. 
         FIG.  7    illustrates a partial sectional view of a liquid soap reservoir of the liquid soap dispenser of  FIG.  2   , including a portion of the reservoir, pump, pump cover, and drive sheave. 
         FIG.  8    illustrates another sectional view of the pump, pump cover, and drive sheave illustrated in  FIG.  7   . 
         FIG.  9    illustrates a partial front, left, bottom perspective view of the liquid soap dispenser of  FIG.  2    with the pump exploded and separated from the bottom of the dispenser. 
         FIG.  9 A  illustrates a bottom view of the pump of  FIG.  9   , with a bottom portion of the pump removed to expose the interface of gears in the pump. 
         FIG.  10    illustrates a front, top, and left side perspective view of another embodiment of a liquid soap dispenser, including a discharge nozzle. 
         FIG.  11    illustrates a right side elevational view of the dispenser of  FIG.  10   . 
         FIG.  12    illustrates a front elevational view of the dispenser of  FIG.  10   . 
         FIG.  12 A  illustrates a cross-sectional view of the dispenser of  FIG.  10    along the line  12 A- 12 A of  FIG.  12   . 
         FIG.  13    illustrates a perspective view of the discharge nozzle of  FIG.  10   . 
         FIG.  13 A  illustrates a perspective view of the discharge nozzle of  FIG.  13    in a compressed state squeezed between two fingers, showing the discharge nozzle in an open configuration. 
         FIG.  14    illustrates a cross-sectional view of the discharge nozzle of  FIG.  13   . 
         FIG.  15    illustrates a cross-sectional view of the discharge nozzle attached to a pipe. 
         FIG.  16    illustrates a perspective view of the discharge nozzle coupled with a mounting flange and an angled member. 
         FIG.  17    illustrates a bottom plan view of the soap pump of  FIG.  10    with another embodiment of a discharge nozzle. 
         FIG.  18    illustrates a perspective view of the discharge nozzle of  FIG.  17   . 
         FIG.  19    illustrates another perspective view of the discharge nozzle of  FIG.  18   . 
         FIG.  20    illustrates a left side exploded view of the discharge nozzle of  FIGS.  17 - 19    coupled with an angled member and a fluid supply source. 
         FIG.  21    illustrates a bottom left perspective view of the discharge nozzle, angled member, and fluid supply source of  FIG.  20    in an assembled state. 
         FIG.  22    illustrates top, left, rear perspective view of the soap pump of  FIG.  10   , with a top portion of a housing removed to expose certain components. 
         FIG.  22 A  illustrates a focused top, left, rear perspective view of a portion of the housing of  FIG.  22   . 
         FIG.  23    illustrates a focused top, right, rear perspective exploded view of the housing of  FIG.  22    and the discharge nozzle, angled member, and a fluid supply source of  FIGS.  20  and  21   . 
         FIG.  23 A  illustrates a focused top, right, rear assembled perspective view of the housing of  FIG.  22    and the discharge nozzle, angled member, and a fluid supply source of  FIGS.  20  and  21   . 
         FIG.  24    illustrates a front, top, left perspective view of another embodiment of a discharge nozzle, including concave cutouts. 
         FIGS.  25 A- 25 C  illustrate front views of outlets of three embodiments of discharge nozzles for a soap pump. 
         FIG.  26    illustrates a top, left, front perspective and partial cross-sectional view of the dispenser of  FIG.  10   , including a pump and a reservoir with an outlet. 
         FIG.  27    illustrates a bottom front perspective view of an embodiment of the pump of  FIG.  26   . 
         FIG.  28    illustrates a top front perspective of the pump of  FIG.  26   . 
         FIG.  29    illustrates top rear perspective of the pump of  FIG.  26   , the pump having an upper member, a lower member, and gears. 
         FIG.  29 A  illustrates a top rear perspective of the upper member of  FIG.  29   . 
         FIG.  30    illustrates a perspective view of one of the gears of  FIG.  29   . 
         FIG.  31    illustrates a top plan view of the gear of  FIG.  30   , the gear including teeth. 
         FIG.  31 A  illustrates a focused view of an alternate configuration of the teeth of the gear of  FIG.  31   . 
         FIG.  32    illustrates a top cross-sectional view of the pump of  FIG.  27   , along the line  32 - 32 . 
         FIGS.  33 - 36    illustrate another embodiment of a soap dispenser, the dispenser including sensing regions. 
         FIG.  37    is a schematic block diagram of an example of a soap dispenser control algorithm. 
         FIG.  38    illustrates another embodiment of a soap dispenser, the dispenser including a disposable soap cartridge. 
         FIG.  39    illustrates an embodiment of a soap dispenser, including a lid. 
         FIG.  40    illustrates a rear view of the embodiment of  FIG.  39   , including a port. 
         FIG.  41    illustrates a focused view of the embodiment of  FIG.  39    showing the port. 
         FIG.  42    illustrates a front view of the embodiment of  FIG.  39    with a portion of the housing removed. 
         FIG.  43    illustrates a partial view of the embodiment of  FIG.  39    with the lid in an open position. 
         FIG.  44    illustrates a side view of the embodiment of  FIG.  39    with a portion of the housing removed. 
         FIG.  45    illustrates an embodiment of a soap dispenser, including an upper portion and a lower portion. 
         FIG.  46 A  illustrates the upper portion of the embodiment of  FIG.  45   . 
         FIG.  46 B  illustrates the lower portion of the embodiment of  FIG.  45   . 
         FIG.  47    illustrates a bottom view of the upper portion of the embodiment of  FIG.  45    with a portion of a housing removed. 
         FIG.  48    illustrates a top view of the upper portion of the embodiment of  FIG.  45    with a portion of the housing removed. 
         FIGS.  49 - 50    illustrate a side view of the upper portion of the embodiment of  FIG.  45    with the housing removed. 
         FIG.  51    illustrates an embodiment of a pump. 
         FIG.  52    illustrates a bottom view of the embodiment of  FIG.  51   . 
         FIG.  53    illustrates a portion of the pump body of the embodiment of  FIG.  51   . 
         FIG.  54    illustrates a gear mechanism of the embodiment of  FIG.  54   . 
         FIG.  55    illustrates another embodiment of a soap dispenser, with a cartridge and a pump unit. 
         FIG.  56 A  illustrates a first indication engagement configuration of the cartridge and the pump unit of  FIG.  55   . 
         FIG.  56 B  illustrates a second indication engagement configuration of the cartridge and the pump unit of  FIG.  55   . 
         FIG.  56 C  illustrates a third indication engagement configuration of the cartridge and the pump unit of  FIG.  55   . 
         FIG.  57    illustrates an algorithm for controlling a soap dispenser, such as the embodiment of  FIG.  55   . 
     
    
    
     DETAILED DESCRIPTION 
     A variety of soap dispensers are described below to illustrate various examples that may be employed to achieve one or more desired improvements. These examples are only illustrative and not intended in any way to restrict the general inventions presented and the various aspects and features of these inventions. Furthermore, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. No features, structure, or step disclosed herein is essential or indispensable. 
     With reference to  FIG.  1   , a liquid soap dispenser  10  can include a housing  12 , which can take any shape. In some embodiments, the housing  12  can at least partially contain a liquid handling system  14 . The liquid handling system  14  can include a reservoir  16 , a pump  18 , and a discharge assembly  20 . 
     The reservoir  16  can be any type of container. In the illustrated embodiment, the reservoir  16  can be configured to contain a volume of liquid soap, such as liquid soap for hand washing. In some embodiments, the reservoir  16  can include a lid  22  configured to form a seal at the top of the reservoir  16  for maintaining the liquid soap L within the reservoir  16 . In some embodiments, the lid  22  can include an air vent (not shown), which can allow air to enter the reservoir  16  as the level of liquid soap L falls within the reservoir  16 . In some variants, the reservoir  16  can include an outlet  24  disposed at a lower end of the reservoir  16 . In certain embodiments, the reservoir  16  can be connected to the pump  18  through the opening  24 . 
     In some embodiments, the pump  18  can be disposed below (e.g., directly below) the outlet  24  of the reservoir  16 . In certain embodiments, the pump  18  can be automatically primed due to the force of gravity drawing liquid soap L into the pump  18  through the opening  24 . The pump  18  can be connected to the discharge system  20  with a conduit  26 . Any type or diameter of conduit can be used. 
     The discharge assembly  20  can include a discharge nozzle  28 , such as a flap-type nozzle as described in further detail below. The size and configuration of the discharge nozzle  28  can be determined to provide the appropriate flow rate and/or resistance against flow of liquid soap L from the pump  18 . In some embodiments, the nozzle  28  can be disposed at a location spaced from the lower portion of the housing  12  so as to make it more convenient for a user to place their hand or other body part under the nozzle  28 . 
     The dispenser  10  can include a power supply  60 . In some embodiments, the power supply  60  can be a battery. In certain embodiments, the power supply  60  includes electronics for accepting AC or DC power. In some implementations, the power supply  60  can be configured to interface with a standard domestic electrical supply (e.g., 120 volt alternating current). 
     In certain embodiments, the dispenser  10  has a pump actuation system  30 , which in turn includes a sensor device  32  and a light receiving portion  42 . In some embodiments, a beam of light  44  can be emitted from the light emitting portion  40  and received by the light receiving portion  42 . 
     The sensor  32  can be configured to emit a trigger signal when the light beam  44  is blocked. For example, if the sensor  32  is activated, and the light emitting portion  40  is activated, but the light receiving portion  42  does not receive the light emitted from the light emitting portion  40 , then the sensor  32  can emit a trigger signal. This trigger signal can be used for controlling operation of the motor or an actuator  34 , described in greater detail below. This type of sensor can provide further advantages. 
     For example, because in some embodiments the sensor  32  can be an interrupt-type sensor, it can be triggered when a body is disposed in the path of the beam of light  44 . The sensor  32  is not or need not be triggered by movement of a body in the vicinity of the beam  44 . Rather, in some embodiments, the sensor  32  can be triggered only if the light beam  44  is interrupted. To provide further or alternative prevention of unintentional triggering of the sensor  32 , the sensor  32 , including the light emitting portion  40  and the light receiving portion  42 , can be recessed in the housing  12 . 
     Some implementations provide other additional or alternative advantages. For example, the sensor  32  only requires enough power to generate the low power beam of light  44 , which may or may not be visible to the human eye, and to power the light receiving portion  42 . These types of sensors require far less power than infrared or motion-type sensors. In some embodiments, the sensor  32  can be operated in a pulsating mode. For example, the light emitting portion  40  can be powered on and off in a cycle such as, for example, for short bursts lasting for any desired period of time (e.g., less than or equal to about 0.01 second, less than or equal to about 0.1 second, or less than or equal to about 1 second) at any desired frequency (e.g., once per half second, once per second, once per ten seconds). These different time characteristics can be referred to as an activation period or frequency, which corresponds to the periodic activation of the sensor  32 . Thus, an activation frequency of four times per second would be equivalent to an activation period of once per quarter second. 
     The other aspect of this characteristic can be referred to as an activation duration. Thus, if the sensor  32  is activated for 50 microseconds, 50 microseconds is the activation duration time period. Cycling can greatly reduce the power demand for powering the sensor  32 . In operation, cycling does not degrade performance in some embodiments because the user generally maintains his or her body parts or other appendage or device in the path of the light beam  44  long enough for a detection signal to be generated and to trigger the sensor  32 . 
     The sensor  32  can be connected to a circuit board, an integrated circuit, or other device for triggering the actuator  34 . In some embodiments, the sensor  32  can be connected to an electronic control unit (“ECU”)  46 . The ECU  46  can include one or a plurality of circuit boards, which can provide hard wired feedback control circuits, a processor and memory devices for storing and performing control routines, or any other type of controller. In some embodiments, the ECU  46  can include an H-bridge transistor/MOSFET hardware configuration which allows for bidirectional drive of an electric motor, and a microcontroller such as Model No. PIC16F685 commercially available from the Microchip Technology Inc., and/or other devices. 
     The actuator  34  can be any type of actuator. For example, the actuator  34  can be an AC or DC electric motor, stepper motor, server motor, solenoid, stepper solenoid, or any other type of actuator. In some embodiments, the actuator  34  can be connected to the pump  18  with a transmitter device  50 . For example, the transmitter device  50  can include any type of gear train or any type of flexible transmitter assembly. 
     The dispenser  10  can include a user input device  52 . The user input device  52  can be any type of device allowing a user to input a command into the ECU  46 . In some embodiments, the input device  52  can be in the form of a button configured to allow a user to depress the button so as to transmit a command to the ECU  46 . For example, the ECU  46  can be configured to actuate the actuator  34  to drive the pump  18  any time the input device  52  can be actuated by a user. The ECU  46  can be configured to provide other functions upon the activation of the input device  52 , described in greater detail below. 
     The dispenser  10  can include a selector device  54 . The selector device  54  can be any type of configuration allowing the user to input a proportional command to the ECU  46 . For example, the selector can have at least two positions, such as a first position and a second position. The position of the input device  54  can be used to control an aspect of the operation of the dispenser  10 . 
     For example, the input device  54  can be used as a selector for allowing a user to select different amounts of liquid soap L to be dispensed from the nozzle  28  during each dispensation cycle. When the input device  54  is in a first position, the ECU  46  can operate the actuator  34  to drive the pump  18  to dispense a predetermined amount of liquid soap from the nozzle  28 , each time the sensor  32  is triggered. When the input device  54  is in the second position, the ECU  46  can actuate the actuator  34  to dispense a larger amount of liquid soap L from the nozzle  28 . 
     In some embodiments, the input device  54  can provide a virtually continuous range of output values to the ECU  46 , or a larger number of steps, corresponding to different volumes of liquid soap L to be dispensed each dispensation cycle performed by the ECU  46 . Although the positions of the input device  54  may correspond to different volumes of liquid soap L, the ECU  46  can correlate the different positions of the input device  54  to different duty cycle characteristics or durations of operation of the actuator  34 , thereby at times discharging differing or slightly differing volumes of liquid soap L from the nozzle  28 . 
     The dispenser  10  can include an indicator device  56  configured to issue a visual, aural, or other type of indication to a user of the dispenser  10 . For example, in some embodiments, the indicator  56  can include a light and/or an audible tone perceptible to the operator of the dispenser  10 . In some embodiments, the ECU  46  can be configured to actuate the indicator  56  to emit a light and/or a tone after a predetermined time period has elapsed after the actuator  34  has been driven to dispense a predetermined amount of liquid soap L from the nozzle  28 . The indicator can provide a reminder to a user of the dispenser  10  to continue to wash their hands until the indicator has been activated. This predetermined time period can be at least about 20 seconds, although other amounts of time can be used. The indicator  56  can be used for other purposes as well. 
     Further advantages can be achieved where the indicator can be activated for a predetermined time after the pump has completed a pumping cycle (described in greater detail below with reference to  FIG.  4   ). For example, the ECU  46  can be configured to activate the indicator  56  for 20 seconds after the pump  18  has been operated to discharge an amount of soap from the nozzle  28 . The indicator  56  can be activated at the appropriate time for advising users as to how long they should wash their hands. 
     In some embodiments, the indicator  56  can be a Light Emitting Diode (LED) type light, and can be powered by the ECU  46  to blink throughout the predetermined time period. Thus, a user can use the length of time during which the indicator  56  blinks as an indication as to how long the user should continue to wash their hands with the soap disposed from the nozzle  28 . Other types of indicators and predetermined time periods can be used. 
     In operation, the ECU  46  can activate the sensor  32 , continuously or periodically, to detect the presence of an object between the light emitting portion  40  and the light receiving portion  42  thereof. When an object blocks the light beam  44 , the ECU  46  determines that a dispensing cycle should begin. The ECU  46  can then actuate the actuator  34  to drive the pump  18  to thereby dispense liquid soap L from the nozzle  28 . 
     As noted above, in some embodiments, the ECU  46  can vary the amount of liquid soap L dispensed from the nozzle  28  for each dispensation cycle, depending on a position of the selector  54 . Thus, for example, the dispenser  10  can be configured to discharge a first volume of liquid soap L from the nozzle  28  when the selector is in a first position, and to discharge a second different amount of liquid soap L when the selector  54  is in a second position. 
     As noted above, the indicator  56  can be activated, by the ECU  46 , after a predetermined amount of time has elapsed after each dispensation cycle. Further, the ECU  46  can be configured to cancel or prevent the indicator  56  from being activated if the button  52  has been actuated in accordance with a predetermined pattern. For example, the ECU  46  can be configured to cancel the activation of the indicator  56  if the button  52  has been pressed twice quickly. However, any pattern of operation of the button  52  can be used as the command for canceling the indicator  56 . The dispenser  10  can include other input devices for allowing a user to cancel the indicator  56 . 
     In some embodiments, the ECU  46  can be configured to continuously operate the actuator  34  or to activate the actuator  34  for a maximum predetermined time when the button  52  is depressed. This can allow an operator of the dispenser  10  to manually operate the dispenser to continuously discharge or discharge larger amounts of liquid soap L when desired. For example, if a user of the dispenser  10  wishes to fill a sink full of soapy water for washing dishes, the user can simply push the button  52  and dispense a larger amount of soap than would normally be used for washing one&#39;s hands, such as at least about 3 milliliters or at least about 4 milliliters. 
       FIGS.  2  and  3    illustrate a modification of the dispenser  10 , identified generally by the reference numeral  10 A. Some of the components of the dispenser  10 A can be the same, similar, or identical to the corresponding components of the dispenser  10  illustrated in  FIG.  1   . These corresponding components are identified with the same reference numeral, except that an “A” has been added thereto. 
     As shown in  FIGS.  2  and  3   , the lower portion  100  of the dispenser  10 A can be designed to support the housing  12 A on a generally flat surface, such as those normally found on a countertop in a bathroom or a kitchen. Further, some embodiments of the dispenser  10 A are movable. For example, the dispenser  10 A can be readily relocated from one position to another position on a countertop. In some implementations, the dispenser  10 A is not attached, embedded, or otherwise joined with a surface that supports the dispenser  10 A. For example, certain implementations of the dispenser  10 A are not mounted to, or recessed in, a countertop or wall. 
     In some embodiments, the nozzle  28  can be disposed in a manner such that the nozzle  28 A extends outwardly from the periphery defined by the lower portion  100 . If a user misses soap dispensed from the nozzle  28 A, and the soap L falls, it will not strike on any portion of the housing  12 A. This helps prevent the dispenser  10 A from becoming soiled from dripping soap L. The configuration and functionality of the nozzle  28 A is described in greater detail below with reference to  FIGS.  10 - 16   . 
     In some embodiments, the indicator  56 , which can be a visual indicator such as an LED light, can be positioned on the outer housing  12 A, above the nozzle  28 A. As such, the indicator  56 A can be easily seen by an operator standing over the pump. In some embodiments, the visual type indicator  56 A can be disposed on a lower portion of the housing (illustrated in phantom line). However, the indicator  56 A can be positioned in other locations, such as on an upper portion of the housing, at or near the discharge nozzle  28 , or otherwise. 
     As shown in  FIG.  3   , the reservoir  16 A can be disposed within the housing  12 A. The pump  18 A can be disposed beneath the reservoir  16 A such that the outlet  24 A of the reservoir  16 A feeds into the pump  18 A. As noted above, this can help the pump  18 A to achieve a self-priming state due to the force of gravity drawing liquid soap L through the outlet  24 A into the pump  18 A. 
     In some embodiments, the reservoir  16 A can include a recess  102 . The actuator  34 A can be disposed somewhat nested with the reservoir  16 A. This can provide for a more compact arrangement and allow the reservoir  16 A to be larger. 
     In some embodiments, the housing  12 A includes a first chamber  104  and a second chamber  106 . The pump  18 A and actuator  34 A can be disposed within the first chamber  104  and the power supply  60 A can be disposed in the second chamber  106 . In some embodiments, the chambers  104 ,  106  can be defined by inner walls of the housing  12 A and/or additional walls (not shown). 
     With reference to  FIGS.  4  and  5   , the button  52 A can be disposed anywhere on the housing  12 A. In some embodiments, as shown in  FIGS.  4  and  5   , the button  52 A can be disposed on an upper portion  110  of the housing  12 A. The button  52 A can be positioned conveniently for actuation by a user of the dispenser  10 A. For example, in some embodiments, the button  52 A can be disposed proximate to an outer periphery of the housing  12 A, on the upper portion  110 , and approximately centered along a rear surface of the housing  12 A. This can provide a location in which a user can easily grasp the outer surface of the housing  12 A with three fingers and their thumb, and actuate the button  52 A with their index finger. 
     Certain embodiments of the housing  12 A include surface textures  112  configured to allow a user to obtain enhanced grip on the housing  12 A when attempting to lift the dispenser  10 A and depress the button  52 A. Such surface textures  112  can have any configuration, such as ridges, bumps, knurls, groves, divots, holes, or otherwise. In some embodiments, the surface textures  112  can be in the form of finger shaped recesses. 
     With reference to  FIG.  6   , as noted above, the dispensers  10 ,  10 A can include a support member arrangement  120  that can achieve the dual functions of providing a support leg or foot for the associated dispenser and provide a sealing function for internal cavities disposed within the associated dispenser. 
     As noted above, the dispenser  10 A can include first and second chambers  104 ,  106  for containing the power supply  60 A and the pump  18 A and actuator  34 A, respectively. Certain implementations include an interior compartment. As shown in  FIG.  6   , an interior wall  122  can be disposed between the chambers  104 ,  106 . 
     The sealing arrangement  120  can include a gasket member  124  and lid members  126 ,  128 . The gasket  124  can be configured to extend around an opening  130  of the compartment  106  and an opening  132  of the compartment  104 . Thus, in some embodiments, the gasket member  124  can include a battery compartment portion  134  and a pump and motor compartment portion  136 . The battery compartment portion  134  can be configured to extend around an interior periphery of the opening  130 . The portion  134  can be configured to straddle a lower-most edge of the opening  130 , or to extend around an outer periphery of the opening  130 . Similarly, the portion  136  can be configured to extend along an inner periphery of the opening  132 . In some embodiments, the portions  134 ,  136  can be configured to rest against a shelf defined along the inner peripheries of the openings  130 ,  132 . In some implementations, a center dividing portion  138  of the gasket  124  can be configured to form a seal along the lower-most edge of the wall  122 . 
     The gasket member  124  can be configured to extend around an opening  130  of the chamber  106  and an opening  132  of the chamber  104 . The lid members  126 ,  128  can be configured to rest against inner walls  140 ,  142  defined by the portions  134 ,  136 , respectively. The lid members  126 ,  128  can be configured to form seals with the inner peripheral walls  140 ,  142 , respectively. In certain such instances, the seals help protect the components disposed within the chambers  104 ,  106 . 
     As shown, in some embodiments, the gasket member  124  can include a battery compartment portion  134  and a pump and motor compartment portion  136 . The battery compartment portion  134  can be configured to extend around an interior periphery of the opening  130 . The portion  134  can be configured to straddle a lower-most edge of the opening  130 , or to extend around an outer periphery of the opening  130 . Similarly, the motor compartment portion  136  can be configured to extend along an inner periphery of the opening  132 . In some embodiments, the portions  134 ,  136  can be configured to rest against a shelf defined along the inner peripheries of the openings  130 ,  132 . 
     In some embodiments, fasteners  140  can be used to secure the lid members  126 ,  128  to the housing  12 A. For example, the lid members  126 ,  128  can include apertures  142  through which the fasteners  140  can extend. The fasteners  140  can engage mounting portions disposed within the housing  12 A. As such, the lid members  126 ,  128  can be secured to the housing  12 A and form a seal with the gasket member  124 . 
     In certain implementations, at least one of the lid members  126 ,  128  includes an additional aperture  144  configured to allow access to a device disposed in one of the chambers  104 ,  106 . In the illustrated embodiment, the aperture  144  is in the form of a slot. However, any type of aperture can be used. The slot  144  can be configured to allow a portion of the selector  54  to extend therethrough. For example, the selector  54 A can be in the configuration of a slider member  150  slidably disposed in a housing  152 . For example, the selector  54  can be in the configuration of a rheostat or other type of input device that allows for a proportional signal. 
     For example, as noted above, the housing  152  can be configured to allow the slider member  150  to be slid between at least two positions. For example, the two positions can be a first position corresponding to a first amount of liquid soap L to be discharged by the nozzle  28 A and a second position corresponding to a second larger volume of liquid soap L to be discharged by the nozzle  28 A. The housing  152  can be configured to allow the slider member  150  to be slid between a plurality of steps or continuously along a defined path to provide continuously proportional signals or a plurality of steps. 
     In some embodiments, with the gasket member  124  and lid member  128  in place, the slider member  150  can be configured to extend through the slot  144  such that a user can conveniently move the slider member  150  with the lid  128  in place. In some embodiments, the slider member  150  can be smaller such that a thin object such as a pen can be inserted into the slot  144  to move the slider member  150 . 
     With continued reference to  FIG.  6   , when the lid members  126 ,  128  and gasket member  124  are in place, the chambers  104 ,  106  can be substantially sealed and thus protected from the ingress of water and/or other substances. In some embodiments, as noted above, the gasket member  124  can be configured to extend downwardly from the housing  12 A such that the gasket member  124  defines the lower-most portion of the device  10 A. The gasket member can provide a foot or a leg for supporting the device  10 A. 
     Further, in a configuration in which the lower-most edge of the gasket member  124  can be substantially continuous and smooth, the gasket member  124  can provide a suction cup-like effect when it is placed and pressed onto a smooth surface. For example, where the gasket member  124  is made from a soft or resilient material, by pressing the device  10 A downwardly when it is resting on a smooth surface, air can be ejected from the space between the lid members  126 ,  128  and the surface upon which the device  10 A is resting. When the device  10 A is released, the slight movement of the device  10 A upwardly can result in suction within that space, thereby creating a suction cup-like effect. This effect provides a further advantage in helping to secure or otherwise anchor the device  10 A in place on a counter, which can become wet and/or slippery during this period. 
     With reference to  FIGS.  7 - 9   , the pump  18 A can be configured to be a reversible pump. For example, in the illustrated embodiment, the pump  18 A can be a gear-type pump. This type of a pump can be operated in forward or reverse modes. In some embodiments, a pump can provide a compact arrangement and can provide a 90 degree turn which provides a particularly compact arrangement in the device  10 A. For example, as shown in  FIG.  7   , the outlet  24 A of the reservoir  16 A feeds (e.g., directly) into an inlet of the pump  18 A. In the illustrated embodiment, a lower-most surface of the reservoir  16 A defines an upper wall of the pump  18 A. Thus, in some embodiments, the outlet  24 A also forms the inlet to the pump  18 A. A gasket  160  can extend around the outlet  24 A and be configured to form a seal with a body of the pump  18 A. An outlet  162  of the pump  18 A can be connected to an outlet chamber of the pump  18 A. In certain variants, the outlet  162  can be connected to the conduit  26 A so as to connect the outlet  162  to the nozzle  28 A. 
     Returning to  FIG.  3   , the pump chamber  18 A can include an outlet chamber  25 A. The outlet chamber  25 A can be an area within the pump in which higher pressures of the viscous fluid are generated during pump operation, i.e., pressures that are higher than the pressure at the inlet  24 A. Thus, this high pressure area within the pump drives the viscous fluid out of the pump, through the conduit  26 A, and through the nozzle  28 A. 
     In some embodiments, the dispenser  10 A can include a bypass passage  27 A connecting the interior of the reservoir  16 A with the outlet chamber  25 A. When the pump  18 A is not operating, liquid soap L from the reservoir  16 A can flow through the bypass passage  27 A, into the outlet chamber  25 A, then into the conduit  26 A. When the dispenser  10 A is at rest, liquid soap L flows up into the conduit  26 A until it reaches the same height as the level of liquid soap L in the reservoir  16 A. Thus, the pump  18 A can remain primed and generally full of liquid soap, even when the pump  18 A is off, or at least between soap dispensations and/or right before the pump  18 A is turned on. 
     In some embodiments, the bypass passage  27 A can be a hole with a diameter of at least about 0.4 mm and/or less than or equal to about 2.1 mm. In some embodiments, the diameter of the hole of the bypass passage  27 A can be in the range of about 0.5 mm to about 2.0 mm. Further, in some embodiments, the diameter of the bypass passage  27 A can be about 0.7 mm to about 0.8 mm. 
     In some embodiments, the soap pump  10 A can be immediately or rapidly primed without requiring further procedures by simply filling the reservoir  16 A with liquid soap L and waiting a short amount of time for liquid soap L to flow through the bypass passage  27 A, through the outlet chamber  25 A and into the discharge conduit  26 A as well as through the inlet  24 A down into the pump  18 A. In some embodiments, once liquid soap L has flown into these parts of the system, the pump  18 A is fully primed and ready to begin pumping liquid soap L at any time, without requiring re-priming before the next use. 
     During operation of the pump  18 A, some pressurized liquid soap L from the discharge chamber  25 A can be discharged out of the outlet chamber  25 A and back into the reservoir  16 A. This discharging from the outlet chamber  25 A into the reservoir  16 A results in some loss of efficiency of pump operation. However, when this pump design is used in conjunction with an anti-drip valve having a low opening pressure, such as an opening pressure of less than or equal to about 1 psi (liquid soap in the discharge nozzle  28 A having a pressure 1 psi higher than atmospheric on the outside of the nozzle  28 A), the loss of efficiency caused by the bypass passage  27 A is generally equal to or overcome by the lower energy requirements for pumping the liquid soap L to a pressure much lower than that required for opening spring-biased type valves. It has been found that where the valve  28 A is configured to open with a pressure of about 0.3 psi or less, and the diameter of the bypass passage  27 A is within the range of about 0.5 mm to about 2 mm, a 40% loss of fluid through the bypass passage  27 A still requires about the same amount of energy or results in an overall reduction in energy required for pumping liquid soap L through the pump  18 A to the lower opening pressure required to open the valve  28 A, compared to valves that are formed of a valve seat and a valve body bias towards the closed position with a spring. 
       FIG.  9    illustrates an exploded view of the pump  18 A. As shown, the gear pump  18 A can include a pair of gears  170  and a gear pump body  172 , from which the outlet  162  extends. The gears  170  can each include a plurality of teeth  169  ( FIG.  9 A ), which in turn can have flanks  171  and a tip  177 . Each of the teeth  169  can have a tooth width W 1  and a tip width W 2 , as will be discussed in further detail below. 
     The pump body  172  can comprise a generally continuous loop (e.g., an oval and/or partially figure-eight-shaped chamber) in which the gears  170  rotate. This configuration is well known in the art, and in particular, with regard to devices known as gear pumps. Thus, a further description of the operation of the gear pump  18 A is not included herein. 
     The body  172  can include a drive shaft aperture  174 . A gasket  176  can be configured to form a seal against the aperture  174  and a drive shaft  178 . One end of the drive shaft  178  can be connected to a driven sheave  180 . The other end of the drive shaft  178  can extend through the gasket  176 , the aperture  174 , and engage with one of the gears  170 . In some embodiments, the other of the gears  170  can engage a boss  179 . 
     In some embodiments, a retaining member  182  can be used to retain the pump body  172  against the lower face of the reservoir  16 A. For example, in the illustrated embodiment, four fasteners  184  extend through corresponding apertures in the retaining member  182  and into engaging portions  186  attached to the lower face of the reservoir  16 A. 
     As shown in  FIG.  9 A , in some embodiments, the gears  170  can be meshed within the chamber. Thus, when a shaft  178  is rotated to rotate one of the gears  170 , the other gear  170  is also rotated. As such, the pump  18 A can displace fluid entering the pump body  172  (e.g., through the outlet  24 A of the reservoir) and discharge the fluid through the outlet  162 .  FIG.  9 A  also shows that the pump body  172  can include an opening  163 . In some embodiments, the opening  163  can be in fluid communication with the outlet  24 A of the reservoir  16 A, thereby allowing liquid soap L to flow into the pump body  172  via the opening  163 . As shown, in certain implementations, the opening  163  can be positioned in the top of the body  172 . In some embodiments, a centerline of the opening  163  can be substantially parallel with an axis of rotation of at least one of the gears  170 . In some embodiments, the opening  163  can be directly coupled with the outlet  24 A of the reservoir  16 A. 
     With reference again to  FIG.  6   , the sheave  180  defines a part of the transmitter  50 A. The actuator  34 A can include a drive sheave  190  configured to drive the driven sheave  180  through a flexible transmitter  192 . The flexible transmitter  192  can be any type of flexible transmitter, such as those well known in this art. For example, the flexible transmitter  192  can be a toothed belt, rubber belt, chain, etc. 
     With reference to  FIG.  10   , another embodiment of a soap dispenser is identified generally by the reference numeral  10 B. Some of the components of the dispenser  10 B can be the same, similar, or identical to the corresponding components of the dispensers  10  and/or  10 A discussed above. Some of these corresponding components are identified with the same reference numeral, except that a “B” has been added thereto and/or has replaced the “A” which was added thereto. 
     The dispenser  10 B can include a housing  12 B, which in turn can include a lower portion  100 B, reservoir  16 B, pump  18 B, and a nozzle  28 B. In certain implementations, the pump  18 B and the nozzle  28 B can be in fluid communication via a conduit  26 B (see  FIG.  12 A ). In some embodiments, the nozzle  28 B extends outwardly from a periphery comprising the lower portion  100 B. For example, as shown, the housing  12 B can include a cantilevered portion that includes the nozzle  28 B. In certain configurations, the nozzle  28 B can be positioned such that any soap that would drip from the nozzle  28 B would avoid contacting the housing  12 B. 
     In some embodiments, such as shown in  FIGS.  10 - 12 A , the nozzle  28 B projects from the housing  12 B. For example, the nozzle  28 B can be mounted on the exterior of the housing  12 B of the soap pump  10 B. In some embodiments, the nozzle  28 B can be mounted partially within or completely within the housing of the soap pump  10 B. Further, in the implementation depicted, the nozzle  28 B can be positioned substantially vertically (e.g., a longitudinal axis of the nozzle forms a substantially right angle with a plane on which the dispenser rests). Such a configuration can, for example, facilitate (e.g., by force of gravity) outflow of the soap from the nozzle  28 B. In some implementations, the nozzle  28 B can be positioned at another angle. For example, the nozzle  28 B can be positioned so as to dispense soap horizontally (e.g., substantially parallel to a plane on which the soap pump  10 B rests). 
     With reference to  FIGS.  13 - 16   , the nozzle  28 B generally includes a one-way valve  200 , which can be in the form of a flap-type valve. Such a configuration can, for example, reduce the likelihood that air or contaminants may enter the valve  200 , which could lead to improper soap flow from the nozzle  28 B and/or drying of soap disposed in the nozzle  28 B. Of course, other types and/or configurations of one-way valve are contemplated, such as flap valves, ball valves, diaphragm valve, lift valves, other kinds of check valves, and the like. 
     In some embodiments, the nozzle  28 B can include an inlet collar  210  with an interior passage  212  having inlet end  214  and an outlet end  216 . The valve  200  can be formed with at least a deflectable member  218 , such as a flap. In some embodiments, the deflectable member  218  can be configured to move toward an open position (illustrated in phantom) when a pressure condition is satisfied. The pressure differential (compared to the ambient pressure acting on an exterior surface of the nozzle  28 B) at which the deflectable member  218  begins to move toward the open position, and thus the nozzle  28 B begins to open, can be referred to as the “cracking pressure.” In some embodiments, the cracking pressure can be at least about 0.2 psi and/or equal to or less than about 0.3 psi. In some embodiments, the cracking pressure is less than or equal to about 0.4 psi. 
     In the illustrated embodiment, the valve  200  includes two slanted deflectable members  218 ,  220  that form an acute angle with each other. Such a configuration is sometimes referred to as a “duckbill valve”. However, a duckbill valve is merely one type of deflectable member valves that can be used as the nozzle  28 B. 
     The valve  200  can be formed from any flexible material, For example, the valve  200  can be made of nitrile, nitrile rubber, fluorosilicone, fluorosilicone rubber, ethylene propylene, ethylene propylene diene monomer rubber, silicone, silicone rubber, hydrogenated nitrile rubber, hydrogenated nitrile butadiene rubber, butyl rubber, isobutylene isoprene rubber, fluorocarbon rubber, polyisoprene, industrial rubber, natural rubber, epichlorohydrin, chloroprene, polyurethane, polyurethane, polyether urethane, styrene-butadiene, styrene-butadiene rubber, polyacrylate acrylic, polyacrylate rubber, ethylene acrylic rubber, combinations thereof, or other materials. Some such duckbill valves are commercially available from Vernay Laboratories, Inc., of Yellow Springs, Ohio. In some embodiments, one or both of the deflectable members  218 ,  220  have a thickness of at least 0.4 mm and/or equal to or less than 0.8 mm. In certain instances, one or both of the deflectable members  218 ,  220  have a thickness of at least about 0.6 mm. 
     The valve  200  can include a seal formed between the deflectable members  218 ,  220 . For example, in certain embodiments the deflectable members  218 ,  220  form a substantially airtight seal therebetween. Some embodiments of the deflectable members  218 ,  220  form a substantially liquid-tight seal therebetween. Some embodiments have deflectable members  218 ,  220  that form a seal that is sufficient to inhibit the passage of viscous soap therebetween. In certain embodiments, the valve  200  can be configured to inhibit the passage of viscous soap yet permit an amount of ambient air to pass through the valve  200  (e.g., and into the interior of the dispenser  10 B). Such a configuration can, for example, reduce the incidence of a pressure differential between the ambient environment and components of the dispenser  10 B. For example, certain configurations allow an amount of ambient air to enter the reservoir  16 B, thereby avoiding the maintenance of a pressure differential between the ambient environment and the reservoir  16 B, which could inhibit opening of the reservoir  16 B, e.g., in order to deposit liquid soap into the reservoir. 
     In some embodiments, the duckbill valve aids in the dispensation of soap, reduces wear, and/or facilitates priming of the dispenser  10 B. For example, certain other anti-drip valves have a valve seat and a valve body that is pressed against the valve seat to prevent dripping when the pump is not operating. However, such valves can require a significant pressure (e.g., 2.5 to 3 psi) in the liquid soap before the spring biased valve body will move away from the valve seat to allow liquid soap to flow out. Generating such liquid soap pressure can require a significant amount of electrical energy. In contrast, some duckbill-type embodiments of the valve  200  can be configured to open (e.g., deflect one or both of the deflectable members  218 ,  220 ) at much lower pressures, such as less than or equal to 0.2 psi and/or greater than or equal to 0.3 psi. As such, certain embodiments of the valve  200  require less electrical energy usage per dispensation, which in turn can prolong the operational life of batteries (or other electrochemical or other electrical energy storage devices) in embodiments of the dispenser  10 B so powered. Further, as the actuating pressure is reduced, some embodiments of the valve  200  reduce the wear on the motor  34 , pump  18 B, and/or other components of the dispenser  10 B. 
     In some embodiments, the reduced actuating pressure of the valve  200  can facilitate priming of the dispenser  10 B. In certain other types of valves, during priming of the pump, air present in a pipe connecting the pump and the valve is trapped between the valve and the leading edge of the flow of soap being urged through the pipe. In some such instances, the air is compressed to the actuating pressure of the valve (which, as indicated above, can be relatively high) and expelled out of the valve in a rush, which can cause the air or soap located in the valve to be ejected in an uncontrolled or otherwise undesirable manner (e.g., in a sputter). In contrast, the reduced actuating pressure of the valve  200  can reduce the amount that air in the conduit  26 B is compressed prior to the valve  200  opening, and thus can reduce or avoid such an uncontrolled or undesirable dispensation during priming. 
     Certain implementations of the valve  200  can reduce or avoid sticking problems found in certain other valve configurations. For example, in valves including a valve body that is pressed against a valve seat, a thin film of soap between the body and seat can encourage the body and seat to stick to each other (e.g., the thin film of soap can act as an adhesive), which can inhibit or prevent the valve from opening. Such an issue can be especially prevalent in designs in which the valve body must move generally against the flow of soap in order for the valve to open. In contrast, certain embodiments of the valve  200  are opened by deflecting the deflectable members  218 ,  220  an acute angle with respect to the direction of the flow of soap through the valve  200 . Further, as certain embodiments of the valve  200  do not include a spring pressing a valve body against a valve seat with a thin film of soap therebetween, the occurrence, or at least the degree, of sticking can be reduced or avoided. 
       FIG.  13    illustrates the valve  200  in a closed position, e.g., the deflectable members  218 ,  220  are in contact with each other thereby substantially closing the outlet end  216  so as to resist the outflow of soap in most circumstances of normal use until the valve  200  is opened. In contrast,  FIG.  13 A  illustrates the valve  200  in an open position, e.g., the deflectable members  218 ,  220  have moved apart from each other, thereby opening a channel between the deflectable members  218 ,  220  through which fluid can flow. For example, in the open state, soap can pass from the inlet  214  and through the outlet  216 , such as to be dispensed to a user&#39;s hands. As shown, the valve  200  can be opened by applying force on the valve  200  along an axis generally parallel with a line formed by the interface of the deflectable members  218 ,  220 . Although  FIG.  13 A  illustrates the valve  200  being squeezed, and thereby opened, by the fingers of a human hand, in the dispenser  10 B, the valve  200  is typically opened in other ways, such as by pressurized liquid soap acting against the deflectable members  218 ,  220 . 
     In a first state, such as when the pump  18 B is not operating, ambient pressure acts against the outer surfaces of the deflectable members  218 ,  220 , thereby pressing them toward each other and closing the outlet  216  of the valve  200 . Such closure of the outlet can, for example, inhibit or prevent liquid soap L within the nozzle  28 B from leaking past the deflectable members  218 ,  220 , for example, under the influence of gravity. In a second state, such as when the pump  18 B operates, liquid soap L is encouraged toward the inlet  214 , which in turn generates pressure within the liquid soap L in the nozzle  28 B. When the pressure of the soap in the nozzle  28 B is greater than or equal to the cracking pressure of the valve  200 , the liquid soap L can deflect the deflectable member  218 ,  220  and thereby be discharged out of the nozzle  28 B. In some embodiments, the cracking pressure of the valve  200  can be at least about 0.2 psi and/or less than or equal about 0.3 psi greater than atmospheric pressure of the environment in which the dispenser  10 B is located. In some embodiments, the cracking pressure can be at least about 0.3 and/or equal to or less than about 0.5 psi.  FIGS.  15  and  16    illustrate some configurations in which the valve  200  can be applied to the dispenser  10 B.  FIG.  15    illustrates a straight connection configuration. In some such embodiments, the collar  210  of the valve  200  can fit over the outer surface of a liquid soap pipe  230 , which can be in fluid communication with the reservoir  16 B and/or the pump  18 B. In some configurations, the collar  210  and the pipe  230  mate in substantially liquid-tight engagement to resist soap leakage. Thus, in certain embodiments, liquid soap L can pass from the reservoir  16 B and/or the pump  18 B, through the pipe  230 , and be discharged out of the valve  200  in a direction generally parallel with the longitudinal axis of the conduit  230 . 
       FIG.  16    illustrates a curved or angled connection between the valve  200  and the liquid soap dispensing system (e.g., a substantially 90° configuration). In some embodiments, an angled member  240  (e.g., an elbow, curve, angle, or otherwise) includes an inlet end  242  and an outlet end  244 . The inlet end  242  of the angled member  240  can be connected to a fluid supply source  246 , which can be in fluid communication with the reservoir  16 B and/or the pump  18 B. In some embodiments, the longitudinal axis of the inlet end  242  can be angled (e.g., at least: about 15°, about 30°, about 60°, about 90°, values therebetween, and otherwise) relative to the outlet end  244  of the angled member  240 . Thus, when the nozzle  28 B is attached to the outlet  244  of the angled member  240 , soap can be discharged through the valve  200  at an angle (e.g., about 90°) relative to the inlet  242 . 
     In some embodiments, the angled member  240  can include a mounting member, such as a flange  250 . In the illustrated embodiment, the flange  250  includes an aperture  252 . In some implementations, a fastener  254  (such as a threaded fastener, rivet, boss, hook, or otherwise) can be used to attach the angled member  240  and the housing  12 B of the soap dispenser  10 B. 
       FIG.  17    illustrates another embodiment of a nozzle  28 C, which can be installed in the housing  12 B. In some embodiments, the nozzle  28 C protrudes from the housing  12 B. For example, in certain embodiments, the nozzle  28 C can be at least partly visible to an observer outside the dispenser. In some embodiments, the nozzle  28 C can be oriented such that the nozzle outlet  375  is generally perpendicular to a front-to-back axis  114  (also illustrated in  FIG.  4   ) of the housing  12 B. In certain embodiments, the nozzle outlet  375  may be oriented such that it is not perpendicular to the axis  114 . 
     With reference to  FIGS.  18  and  19   , the nozzle  28 C can be in the form of a valve  300 . As noted above, such a configuration is sometimes referred to as a “duckbill valve.” In some embodiments, the valve  300  can include an inlet collar  310 , deflectable members  318 ,  320 , and a valve flange  350 . In some embodiments, the valve flange  350  can have one or more first positioners, such as an indentation  335 . For example, as illustrated in  FIGS.  18  and  19   , the indentation  335  can be a single indentation. In some embodiments, the indentation  335  comprises a plurality of indentations. As shown, some embodiments of the inlet collar  310  can be cylindrically shaped. Some embodiments of inlet collar  310  have various other shapes, such as rectangular or triangular prismatic. 
       FIGS.  17 - 19    illustrate the deflectable members  318 ,  320  in a generally closed position. In some variants, when the pump  18  is not operating, the deflectable members  318 ,  320  can be pressed together, thereby closing the valve  300  and inhibiting or preventing liquid soap L in the nozzle  28 C from leaking past the deflectable members  318 ,  320  (e.g., by the influence of gravity). In certain implementations, one or both of the deflectable members  318 ,  320  can be biased toward the other, thereby pressing the deflectable members  318 ,  320  together when the pump  18  is not operating. In some embodiments, the deflectable members  318 ,  320  atmospheric pressure acts against the outer surfaces of the deflectable members  318 ,  320  to press the deflectable members  318 ,  320  together. 
     When the pump  18  operates and generates sufficient pressure within the liquid soap L in the nozzle  28 C, the liquid soap L can open the nozzle  28 C by deflecting the deflectable members  318 ,  320 , thereby discharging the liquid soap from the nozzle  28 C. As previously noted, the pressure differential (compared to ambient atmospheric pressure) at which the nozzle  28 C begins to open can be referred to as the “cracking pressure.” In some embodiments, the cracking pressure required to discharge the liquid soap L from the nozzle  28 C can be at least about 0.2 psi and/or equal to or less than about 0.3 psi above atmospheric pressure. In some embodiments, the cracking pressure required to discharge the liquid soap L from the nozzle  28 C can be at least about 0.3 and/or equal to or less than about 0.5 psi. 
       FIGS.  20  and  21    illustrate a configuration in which the valve  300  can be applied to a liquid soap dispensing system.  FIG.  20    illustrates the valve  300  and an angled member  340 , such as an elbow of about 90°, in an unconnected state. As shown, the angled member  340  can include an inlet end  342  and an outlet end  344 . The inlet end  342  can be connected to a fluid supply source  346 , which can be in fluid communication with the reservoir  16 B and/or pump  18 B. The outlet end  344  of the angled member  340  can engage with the valve  300 . In some embodiments, the angled member  340  can include a flange  360 . The flange  360  can include one or more second positioners, such as protrusions  370 . 
     As illustrated in the embodiment shown in  FIG.  21   , the valve  300  can be oriented such that the indentation  335  in the nozzle flange  350  generally aligns with the protrusion  370  on the flange  360 . In this embodiment, the protrusion  370  can engage with and/or be received by the indentation  335 . Such a configuration can, for example, inhibit or prevent rotation of the valve  300  with respect to the outlet end  344  of the angled member  340 . Further, in some embodiments, the indentation  335  can ease manufacturing of the dispenser  10 B, as the indentation  335  can facilitate orientation of the nozzle  28 B with regard to the remainder of the dispenser  10 B, thereby facilitating assembly. For example, some configurations of the indentation  335  orient the nozzle  28 C such that the line of contact between the deflectable members  318 ,  320  can be substantially transverse to the axis  114 , which can facilitate dispensing soap into a user&#39;s hands in a desired pattern. 
     In some implementations, the pump  18  and/or actuator  34  can be configured to temporarily (e.g., for less than or equal to about a second) reverse the flow of soap. For example, in embodiments having a gear pump, the rotation of the gears can be temporarily reversed, thereby drawing soap from the nozzle back toward the reservoir. Such a configuration can, for example, facilitate closing of the nozzle  28 C. For instance, in embodiments having the valve  300  with first and second deflectable members  318 ,  320 , such reversal of flow can encourage closing of the valve  300 . Indeed, in implementations, reversal of flow can reduce the delay that between the intended cessation of dispensation of soap and the actual cessation of dispensation of soap from the nozzle  28 C. In some embodiments, reversing the flow of soap encourages a tight seal between the first and second deflectable members  318 ,  320 . 
     As shown in  FIG.  22   , in some embodiments, the housing  12 B can have an opening  332  in which the nozzle  28 C can be at least partly received. In some embodiments, the opening  332  of the housing  12 B can include a leak inhibiting structure, such as an annular protrusion  390 . In some embodiments, the nozzle flange  350  of the nozzle  28 C can be pressed against the annular protrusion  390 , thereby creating a substantially liquid-tight seal. The opening  332  of the housing  12 B can comprise a positioning structure, such as a ridge  393 . In the embodiment shown in  FIG.  22   , the ridge  393  can include an orienting structure, such as a recess  387 . In certain arrangements, the housing  12 B includes one or more other apertures  333 , such as a sensor device, as was discussed in further detail above. 
       FIG.  23    shows the housing  12 B from  FIG.  22    as well as the assembled nozzle  28 C and angled member  340  of  FIG.  21   . The recess  387  in the ridge  393  can be sized to accept the inlet end  342  of the angled member  340  when at least a portion of the angled member  340  and the nozzle  28 C can be inserted into the opening  332  of the housing  12 B. The recess  387  can, for example, inhibit or prevent the angled member  340  from rotating with respect to the housing  12 B. In some embodiments, a combination of the recess  387  of the ridge  393  and the indentation  335  and protrusion  370  of the assembled nozzle  28 C and angled member  340  can inhibit or prevent the nozzle  28 C from rotating with respect to the housing  12 B.  FIG.  23 A  shows the assembled nozzle  28 C and angled member  340  in an installed position in the housing  12 B. 
     In some embodiments of the nozzle  28 C, the geometry of the deflectable flap members  318 ,  320  can be designed to increase the cracking pressure necessary to open the nozzle outlet  375  of the nozzle  28 C. Configurations like these can, for example, allow the valve  300  to withstand higher internal pressures before permitting a flow of fluid therethrough. Such an increased cracking pressure is desirable in certain applications (e.g., when some or all of the reservoir  16  is positioned higher than the nozzle  28 C). In some instances, an increased cracking pressure facilitates faster and/or increased disbursement of soap. 
     With reference to  FIGS.  24  and  25 A , in some embodiments, the deflectable members  318 ,  320  have biasing features, such as recesses  329 ,  331 . Thus, in certain embodiments, the deflectable members  318 ,  320  have a generally hourglass shape in an end view. In some embodiments, the deflectable members  318 ,  320  with the recesses  329 ,  331  exhibit an increase in the bias between the deflectable members  318 ,  320  compared to deflectable members without such recesses. In some embodiments, the deflectable members  318 ,  320  can be configured such that the concavity the recesses  329 ,  331  produces or increases the bias of the deflectable members  318 ,  320  against each other. 
     In some embodiments of the nozzle  28 C, the geometry of the deflectable members  318 ,  320  can be configured to decrease the cracking pressure needed to open the nozzle outlet  375  of the nozzle  28 C. For example, the recesses  329 ,  331  can be configured such that they reduce the thickness of the deflectable members  318 ,  320  at about the midpoint of the outlet  375  as compared to other regions of the outlet  375  without greatly increasing the radius of concavity. As a result, in certain such implementations, the cracking pressure necessary to open the nozzle outlet  375  of the nozzle  28 C may be reduced. 
     As shown in  FIG.  25 B , some embodiments of the nozzle  28 C include one or more deformation-facilitating members, such as notches  337 ,  339 , in the sides of the nozzle outlet  375 . Notches  337 ,  339  can reduce the compressive force in the material in the vicinity of the notches  337 ,  339 . Thus, the notches  337 ,  339  can allow the sides of the nozzle outlet  375  to deform more easily, thereby facilitating opening of the outlet  375 . In some arrangements, the notches  337 ,  339  resiliently deform during the period that the outlet  375  is open, e.g., opposite sides of the notches can move toward each other. In certain such cases, the resiliently deformed notches  337 ,  339  can provide or increase a biasing effect, which can facilitate the nozzle outlet  375  returning to its original shape when the pressure on the soap (e.g., from the pump) eases. Such a configuration can, for example, allow the nozzle outlet  375  to close more quickly when the pump  18 B ceases operation.  FIG.  25 B  illustrates an example of this concept in which the opening of the nozzle outlet  375  causes the notches  337 ,  339  to reduce in size as the material surrounding the notches  337 ,  339  compresses. 
       FIG.  25 C  illustrates a configuration wherein both notches  337 ,  339  and concave recesses  329 ,  331  can be utilized for the nozzle outlet  375 . In some embodiments, the concave recesses  329 ,  331  in the deflectable members  318 ,  320  produce or increase the bias of the deflectable members  318 ,  320  to a closed position. Indeed, in certain such instances, the concave recesses  329 ,  331  increase the cracking pressure of the nozzle  28 C. However, when the cracking pressure is reached and the outlet  375  begins to open, the notches  337 ,  339  can facilitate such opening by reducing compressive forces and/or interference of material on the side of the nozzle  28 C. Moreover, the resilient deflection of the notches  337 ,  339  can be biased to return to their original, undeflected position, thereby promoting closing of the opening. In certain such embodiments, closing of the nozzle opening  375  is further promoted by the previously described bias of the deflectable members  318 ,  320 . 
     With regard to  FIG.  26   , a top front perspective and partial cross-sectional view of the dispenser  10 B is illustrated. As previously discussed, the dispenser  10 B includes the reservoir  16 B and pump  18 B. As shown, the reservoir  16 B can include an outlet  24 B, which can be in fluid communication with the pump  18 B. Thus, soap can flow between the reservoir  16 B and the outlet  24 B (e.g., by force of gravity). As discussed in further detail above, the pump  18 B can drive the soap to the nozzle  28 B via the conduit  26 B, in order to be dispensed as desired. 
     As shown in  FIGS.  27 - 29 A , the pump  18 B can include a pump body  272  having an outlet  262  and an inlet  263 . In certain embodiments, the pump body  272  includes an upper member  264  and a lower member  265 . Typically, the members  264 ,  265  can be configured to mate together (e.g., with adhesive, fasteners, a snap fit connection, or otherwise). The pump body  272  can have one or more arms  266  or the like that can be configured to, for example, facilitate mounting the pump body  272  in the housing  12 B. Various materials can be used to form the pump body  272 , such as metal, plastic, or otherwise. In some embodiments, the pump body  272  comprises a polymer, such as a polypropelene, polyoxymethylene, Delrin®, or otherwise. 
     In some embodiments, the pump body  272  houses a driven gear  270  and a slave gear  270 ′. In certain variants, the gears  270 ,  270 ′ can be substantially identical. In some embodiments, the gears  270 ,  270 ′ are not identical. In certain implementations, the gears  270 ,  270 ′ can be configured to rotate in an oval and/or partially figure-eight-shaped space. As shown, certain embodiments of the pump body  272  include a chamber  273  in communication with the inlet  263 . The chamber  273  can, for example, provide a staging location for liquid soap L between the reservoir  16 B and the gears  270 ,  270 ′. 
     In certain implementations, a seal (e.g., made of rubber, silicone, or otherwise) can be positioned between the upper and lower members  264 ,  265 . Such a configuration can, for example, inhibit soap leaking from the pump body  272  and/or reduce the likelihood of air infiltrating the pump body  272  (which in turn could lead to drying of the soap and impede the operation of the pump  18 B). In some embodiments, the seal can be generally positioned along the periphery of the pump body  272 . 
     Similar to the discussion above in connection with  FIG.  9   , in some embodiments, the pump body  272  includes a drive shaft aperture  274  (not shown). A gasket  276  (not shown) can be configured to form a seal against the aperture  274  and a drive shaft  278 . One end of the drive shaft  278  can be connected to a driven sheave  280 . The other end of the drive shaft  278  can extend through the gasket  276 , the aperture  274 , and engage with one of the driven gear  270 . In some embodiments, the slave gear  270 ′ can engage a boss  279 . 
     In certain implementations, the pump body aperture or opening  263  of the pump body  272  can be in fluid communication with the reservoir  16 , thereby allowing liquid soap L to flow into the pump body  272  via the opening  263 . However, in certain arrangements, air can be present in the pump body  272 . For example, air is generally present in the pump body  272  during or at least before priming of the pump. In some cases, air can form a bubble that is retained in the pump body  272  and may interfere with the ability of liquid soap L to flow into the pump body  272 . Such interference can be exacerbated if the opening  263  is too small to allow the bubble to escape (e.g., due to surface tension and frictional forces). Thus, in some embodiments, the opening  263  can be configured to allow air in the pump body  272  to escape. For example, the opening  263  can be configured (e.g., can have a sufficient size and shape) to allow a bubble formed by air present in the pump body  272  to readily pass through the opening  263 , such as during priming of the pump. For example, in some embodiments, the cross-sectional area of the opening  263  (e.g., taken generally in the plane of dimensions  293 ,  294  (see  FIG.  29 A )) can be generally about the same size as, or can be larger than, or can be substantially larger than, the cross-sectional area of the upper region of the gear  270 , or of a tooth  269  of the gear  270 , and/or of a hole  267  of the gear  270  for receiving the drive shaft  278 . In some implementations, the pump body  272  is configured so as to facilitate the flow of the liquid soap L through the opening  263 . In certain embodiments, the opening  263  is configured so as to not retain an air bubble in the pump body  272 . 
     In some embodiments, the opening  263  can be configured to facilitate the liquid soap L flowing into the staging chamber, such as by force of gravity. As the liquid soap L generally can be rather viscous (e.g., between about 100 and about 2,500 centipoise), the surface tension of the liquid soap L may allow the soap to resist the force of gravity in certain arrangements. For example, when certain kinds of liquid soap are disposed directly over a hole, the surface tension of the soap may be sufficient to counteract the effect of gravity acting to urge the soap through the hole. In a soap dispenser, such a configuration can result in the soap being inhibited from reaching the pump, which can result in, for example, difficulty in priming the pump, reduced soap dispensation volume, and/or increased pump wear. 
     Certain embodiments of the pump dispenser  10 B can be configured to reduce the likelihood of, or avoid, such surface tension issues. For example, in some implementations, the opening  263  can be sufficiently sized and shaped so as to facilitate gravity overcoming the surface tension of the soap. In certain variants, a first dimension  293  (e.g., a distance generally parallel with a centerline of the outlet  262 ) of the opening  263  can be greater than or equal to about: 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, values in between, or otherwise. In some implementations, a second dimension  294  (e.g., a distance generally perpendicular to the centerline of the outlet  262 ) of the opening  263  can be greater than or equal to about: 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, values in between, or otherwise. In certain embodiments, the first dimension  293  of the opening  263  can be greater than the second dimension  294  of the opening  263 . For example, the ratio of the first dimension  293  to the second dimension  294  can be at least about three to about two. In some embodiments, the ratio of the first dimension  293  to the second dimension  294  can be about two to about one. In certain variants of the opening  263 , the ratio of the first dimension  293  to the second dimension  294  can be at least about five to about four. In some variants, the sum of the first and second dimensions  293  and  294  can be greater than or equal to about: 10 mm, 12 mm, 14 mm, 16 mm, 18 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, values in between, or otherwise. In some implementations, the opening  263  can be configured to receive a cylinder with a diameter that can be greater than or equal to about: 4 mm, 6 mm, 8 mm, 10 mm, 12 mm, 14 mm, 16 mm, 18 mm, 20 mm, values in between, or otherwise. 
     In certain embodiments, the opening  263  opens directly into the chamber  273 . In some embodiments, the opening  263  opens directly into a second chamber  273 ′ (see  FIG.  32   ) that houses the gears  270 ,  270 ′. Such a configuration can, for example, facilitate the liquid soap L flowing into contact with the gears  270 ,  270 ′, which in turn can facilitate priming of the dispenser  10 B. In some variants, when the pump body  272  is viewed from a top plan view, a portion of at least one of the gears  270 ,  270 ′ is visible though the opening  263 . 
     Some methods of priming the dispenser  10 B include providing the liquid soap L in fluid communication with the pump body  272  and allowing air (e.g., some or all) in the pump body  272  to escape the pump body  272 . For example, some embodiments are configured to allow the air to escape from the pump body  272  via the opening  263 . As previously noted, the opening  263  can be configured to inhibit or avoid the formation and/or trapping of an air bubble that would obstruct (e.g., partially or totally) the opening  263 . Certain implementations can be configured so as to allow some or all of the air to escape from the pump body  272  via other apertures (e.g., apertures in the sides of the top, bottom, and/or sides of the pump body  272 . Some embodiments are configured such that some or all of the air can escape from the pump body  272  via the outlet  262 . Some embodiments of the method of priming include allowing the liquid soap L to enter the pump body  272 . In certain embodiments, the liquid soap L can be at a higher elevation than some or all of the pump body  272 , which can facilitate the liquid soap L being drawn into the pump body  272  by force of gravity. 
     Certain configurations of the opening  263  can, for example, facilitate the passage of air (e.g., a bubble) through the opening  263 , thereby facilitating equilibrium between the pump  18  and the reservoir  16 B and/or assisting in priming the pump  18 . In some embodiments, the opening  263  can have a generally triangular shape. In some embodiments, the opening  263  can have a generally square, elliptical, circular, rectangular, or other regular or irregular polygonal shape. As illustrated in  FIG.  29 A , in certain embodiments, the opening  263  can include a sloped or angled surface (e.g., about 45°) that is wider in cross-section near the exterior than near the interior of the pump body  272 . For example, in some variants, an inner periphery of the opening  263  is not coplanar with an outer periphery of the opening  263 . 
     As illustrated in  FIGS.  28  and  29   , some embodiments include a flexible cushion  227  (e.g., made of rubber, silicone, foam, or otherwise), that can be positioned on, over, or along some or all of the upper member  264  of the pump body  272 . Such a configuration can, for example, reduce the amount of noise from the pump  18 B that is emitted into the ambient environment. In some embodiments, the cushion  227  can be configured to reduce, inhibit, or prevent the transmission of vibration from the pump body  272  to other portions of the dispenser (e.g., the reservoir  16 B or otherwise) or the surface on which the dispenser rests (e.g., a countertop). In certain embodiments, the cushion  227  can be configured to substantially conform to the shape of the pump body  272 . As shown, the cushion can include a void configured to correspond with the opening  163 . In certain embodiments, the cushion  227  can include notched projections  227 ′ configured to correspond with the arms  266 , which can, e.g., provide clearance for a fastener. 
     As previously discussed, the pump body  272  can include gears  270 ,  270 ′, which can be configured to matingly engage. As will be discussed in further detail below, certain embodiments can be configured to enhance the mating engagement of the gears  270 ,  270 ′, which in turn can provide increased pumping power (e.g., the pressure generated by the mating of the gears  270 ,  270 ′) and/or increase efficiency (e.g., by reducing the amount of soap that passes between the gears and back into the chamber  273 ). 
     With regard to  FIGS.  30  and  31   , an embodiment of the driven gear  270  is illustrated. Typically, the slave gear  270 ′ is substantially similar or identical to the driven gear  270 . As shown, the driven gear  270  can include a hole  267  (e.g., to receive the drive shaft  278 ) and a central portion  268  with a plurality of teeth  269  around the periphery. In certain implementations, adjacent teeth  269  can be separated by a root  281 . In some embodiments, the root  281  can have a root radius R 1 , which can reduce stress concentrations, facilitate mating of the gears  270 , or otherwise. In some embodiments, each of the teeth  269  can include a base  259 , flanks  271 , and a tip  277 . 
     In certain embodiments, one or more of the teeth  269  can include a tooth width W 1 . The tooth width W 1  is generally determined at the widest part of the tooth. In some embodiments, such as illustrated in  FIG.  31   , the tooth width W 1  is determined at a location intermediate the base  259  and the tip  277 . In some embodiments, such as in the frustoconically shaped tooth shown in  FIG.  31 A , the first width W 1  is determined at or near the base  259 . 
     Each of the teeth  269  can further include a tip width W 2 . The tip width W 2  is generally the distance between the radially-outward end of the flanks  271 . In some embodiments, the tip  277  comprises a relatively flat section (see  FIGS.  9  and  31 A ) and the tip width W 2  can be about the distance of this flat section. Typically, W 2  is less than or equal to about W 1 . For example, in some embodiments, W 2  can be less than or equal to: about ¼ of W 1 . In some embodiments, the ratio of W 2  to W 1  can be about 1:5, about 1:7.5, about 1:10, about 1:12.5, about 1:15, about 1:20, about 1:25, about 1:30, about 1:35, about 1:40, values in between, or otherwise. 
     In some embodiments, such as is shown in  FIG.  31   , the tip  277  is a section that is pointed (e.g., rounded, chamfered, or the like). In some such embodiments, the tip width W 2  can be the distance between the respective locations in which the radially-outward end of the flank  271  terminates and the radius, chamfer, or the like begins. For example, in embodiments that have a tip  277  with a tip radius R 2 , the tip width W 2  is typically about twice the tip radius R 2 . 
     In some embodiments, the tip radius R 2  of the tip  277  can be less than the root radius R 1 . Such a configuration can, for example, provide a pointed tip  277  and facilitate engagement of the teeth  269  during operation of the pump  18 B. In some embodiments, the tip radius R 2  can be less than or equal to: about ½ of the root radius R 1 , about ⅓ of the root radius R 1 , about ¼ of the root radius R 1 , about ⅛ of the root radius R 1 , about 1/10 of the root radius R 1 , about 1/16 of the root radius R 1 , about 1/20 of the root radius R 1 , about 1/30 of the root radius R 1 , about 1/40 of the root radius R 1 , about 1/50 of the root radius R 1 , values in between, or otherwise. 
     In certain embodiments, the tip  277  forms a substantially sharp or pointed peak. For example, in some embodiments, a slanted left side of a tooth and a generally oppositely slanted right side of the tooth can each converge at approximately the same point on the end of the tooth. In some embodiments, the tip radius R 2  can be less than or equal to: about 0.5 mm, about 0.4 mm, about 0.3 mm, about 0.2 mm, about 0.1 mm, about 0.05 mm, about zero, values in between, or otherwise. Certain conventional wisdom discouraged the use of gears having substantially sharp and/or pointed tips because, for example, such tips could be prone to breaking. Further, substantially sharp and/or pointed tips could be thought to wear more quickly than tips that are flattened. 
     However, employing gears with substantially sharp and/or pointed tips in a soap dispenser can provide substantial benefits. For example, the tip  277  being pointed can, for example, increase the pumping ability (e.g., the pressure generated by the mating of the gears  270 ,  270 ′) of the pump  18 B. As shown in  FIG.  32   , the gears  270 ,  270 ′ of the pump  18 B can be configured to rotate into contact with, or very close to, one another. Typically, as the gears engage, the volume between the tip  277  of one gear and the root  281  of the other gear decreases. Such a decrease in volume can result in an increased pressure area  257 , which in turn can encourage fluid (e.g., soap) to flow toward the outlet  262 . In general, the more fully the teeth  269  of the gears  270 ,  270 ′ engage each other, the greater the increase in pressure in the area  257 . In certain embodiments, gears with teeth  269  having pointed tips  277  more fully engage (e.g., have a greater percent of contact with) the mating teeth compared to, for example, gears with teeth  269  having flat tips  277 . For example, certain embodiments of the pointed tips  277  project further toward the root  281  than the flat tips  277 . At least due to such increased engagement, certain embodiments of the gears  270 ,  270 ′ having teeth  269  with pointed tip  277  can facilitate increasing the pressure in the increased pressure area  257 . 
     In some instances, a pointed tip  277  can increase the efficiency of the pump  18 B. In embodiments having a flat tip  277 , soap can be trapped or otherwise disposed between the flat tip  277  of one gear and the root  281  of the mating gear, which can result in soap being carried through the mating portion of the gears  270 ,  270 ′ and back into the chamber  273 , rather than the soap being expelled out the pump outlet  262 . In contrast, a pointed tip  277  can allow the gears  270 ,  270 ′ to more fully engage. For example, the pointed tip  277  can reduce the volume available for soap to be present between the tip  277  of one gear and the root  281  of the mating gear tip  277 . Thus, the likelihood and/or the volume of soap carried through the mating portion of the gears  270 ,  270 ′ and back into the chamber  273  can be reduced, thereby increasing the efficiency of the pump  18 B. 
     As previously noted, the pump body  272  can include the chamber  273 , which can be in communication with inlet  263 . Further, in some embodiments, the pump body  272  can include the second chamber  273 ′. The second chamber  273 ′ can house the gears  270 ,  270 ′ and can be in communication with the inlet  262 , outlet  262 , and/or chamber  273 . As shown in  FIG.  32   , in certain embodiments, together the chambers  273 ,  273 ′ form an overall figure-eight shape. Such a configuration can, for example, provide space for staging soap in the pump body  272  and space for housing and operation of the gears. In some embodiments, the chamber  273  can be smaller than the second chamber  273 ′. In certain implementations, the chamber  273  can hold less soap than the second chamber  273 ′. In some embodiments, the chamber  273  can hold about as much soap as the second chamber  273 ′. 
     In some embodiments, the passage between the chamber  273  and the second chamber  273 ′ can be configured such that the liquid soap L can readily pass therethrough. For example, in some variants, the passage between the chamber  273  and the second chamber  273 ′ can be configured such that the weight of liquid soap L in the chamber  273  overcomes the surface tension of the liquid soap L and thus moves the soap into a portion of the second chamber  273 ′. Accordingly, the passage can be configured so as to reduce or avoid the chance of surface tension of the soap inhibiting the soap from reaching the gears  270 ,  270 ′. In certain embodiments, the width of the passage (indicated by the dashed line in  FIG.  32   ) can be greater than or equal to the first dimension  293  and/or the second dimension  294  of the opening  263 . 
     With reference to  FIGS.  33 - 36   , another embodiment of a dispenser is identified generally by the reference numeral  10 D. The dispenser  10 D can include a housing  12 D, which in turn can include a lower portion  100 D, an upper portion  110 D, reservoir  16 D, and a nozzle  28 D. Some of the components of the dispenser  10 D can be the same, similar, or identical to the corresponding components of the dispensers discussed above. Some of these corresponding components are identified with the same reference numeral, except that a “D” has been added thereto and/or has replaced the “A,” “B,” or “C.” 
     In certain embodiments, the dispenser  10 D has a sensor device  32 D. The sensor  32 D can be configured to emit a trigger signal used to control operation of a motor or an actuator. In some embodiments, the sensor  32 D can be an interrupt-type sensor. The sensor  32 D can be triggered when a body part is disposed in the path of a beam of light  44 D or some other mechanism interrupts the light beam  44 D. In some embodiments, the sensor  32 D can be a proximity sensor or a reflective type sensor that is configured to send a different signal to the ECU based on the distance between an object and the sensor. For the purposes of simplifying the examples described below, a hand H is used to trigger the sensor  32 D, but any number of other objects or mechanisms could be used to trigger the sensor  32 D. 
     The sensor  32 D can be positioned along any portion of the housing surface or the sensor can be a separate component. As shown in  FIGS.  33 - 36   , the sensor  32 D can be on the upper portion  110 D of the soap dispenser. The sensor  32 D can be positioned along a surface that is generally transverse to the longitudinal axis of the soap dispenser. The sensor  32 D can be positioned near the nozzle  28 D. The sensor  32 D can be positioned such that the sensor detects the hand H when the hand is positioned under the nozzle  28 D. 
     In some embodiments, the dispenser  10 D can include one or more sensing regions  41 D to trigger one or more sensor devices  32 D. If a signal is detected in a sensing region, the sensor can trigger the dispenser to perform a specific operation based on the particular signal. For example, the specific operation may vary based on the distance between a hand H and the sensor  32 D, and/or other parameters such as angle, duration, repetition, path of motion, and/or speed of motion. All descriptions of changing dispensing performance based on sensing regions included herein can be applied for use with these or other parameters besides or in addition to sensing regions. 
     The one or more sensing regions  41 D may take on any shape, width, height, or length. The one or more sensing regions  41 D can be positioned in any number of configurations in relation to each other and the dispenser  10 D and are not limited to the regions depicted in  FIGS.  33 - 36   . In some embodiments, a first sensing region  41 Da can be positioned adjacent to or near a second sensing region  41 Db; while in some embodiments, the first sensing region  41 Da is not positioned adjacent to or near the second sensing region  41 Db. The first and second sensing regions  41 Da,  41 Db can be disposed in proximity to any portion of the housing  12 D. In some embodiments, one or more sensing regions  41 D are positioned in an area that is between the nozzle  28 D and the lower portion  100 D, while in some embodiments, one or more sensing regions  41 D are positioned in an area that is above the upper portion  110 D of the dispenser  10 D. 
     The one or more sensing regions  41 D can be used in any type of configuration that allows the user to control an aspect of the operation of the dispenser  10 D. For example, the one or more sensing regions  41 D can be used to trigger the dispenser  10 D to dispense different volumes of liquid L, activate different duty cycle characteristics, dispense at different speeds, operate for varying durations of time, or other appropriate parameters. The examples below will be explained in the context of a dispenser  10 D configured to dispense different volumes of liquid, but the dispenser can be configured to dispense liquid with one or more of any of the outputs described above. 
     These features allow the same touch-free dispenser to be used by different users who may desire different outputs or by the same user for different purposes without requiring direct physical contact between the hands and a physical pump switch or other adjustment. For example, an adult and a child can use the same dispenser to obtain a volume of liquid soap that is proportional to their hand size or the same person can adjust the volume of soap dispensed depending on how dirty his/her hands are. A user can also use the same touch-free soap dispenser to wash his/her hands or wash a kitchen sink full of dishes. 
     In several embodiments, the one or more sensing regions  41 D can be configured to allow a user to select different volumes of liquid L to be dispensed from the nozzle  28 D during each dispensation cycle. As shown in  FIGS.  33  and  35   , no liquid is dispensed when no signal is detected within any of the sensing regions  41 D. On the other hand, in  FIGS.  34  and  36   , a predetermined volume of liquid L is dispensed when a signal is detected within one of the sensing regions  41 D. As illustrated in  FIG.  34   , when a signal is detected in a sensing region  41 Db, the sensor  32 D triggers the dispenser  10 D to dispense a first predetermined volume of liquid L 1  from the nozzle  28 D. In  FIG.  36   , when a signal is detected in a different sensing region  41 De, the sensor triggers the dispenser to dispense a second predetermined volume of liquid L 2  from the nozzle  28 D that is different from the first volume of liquid L 1 . 
     In some embodiments, when a signal indicating that an object is disposed in a first region (e.g., relative to the sensor) is received, a first volume of liquid dispensed. In some embodiments, when a signal indicating that an object is disposed in a second region (e.g., further from the sensor than the first region) is received, a second volume of liquid is dispensed. In certain embodiments, the second volume is larger than the first volume. One or more additional sensing regions and liquid volumes can be used. In certain implementations, the volume of liquid dispensed is related (e.g., linearly, exponentially, or otherwise) to the distance from the sensor to the object. For example, in certain embodiments, the volume of liquid dispensed increases as the distance from the sensor to the object increases. In some embodiments, the volume of liquid dispensed decreases as the distance from the sensor to the object increases. 
     In some embodiments, the one or more sensing regions are positioned in a manner that corresponds with natural human conduct or instinct. For example, a child may be more inclined to hold his/her hands closer to the nozzle, so, in some embodiments, a sensing region positioned closer to the nozzle would dispense a smaller volume of liquid than a sensing region positioned further away from the nozzle. 
     In some embodiments, the volume of dispensed liquid does not depend solely or at all on the length of time that the object remains in the sensing region. The dispensed volumes can differ depending on the location of the object (e.g., hand) in a different sensing region, even if certain other parameters are the same (such as the length of time that the object is sensed in a region). 
     In some embodiments, the dispenser  10 D includes an algorithm configured to send a command to trigger the dispenser to dispense different volumes of liquid based on the detected signal. For example, the algorithm can send a command to trigger the dispenser to dispense a first pre-determined volume of liquid L 1  if a signal is detected in a first sensing region  41 Da, or the algorithm can send a command to trigger the dispenser to dispense a second pre-determined volume of liquid L 2  if a signal is detected in the second sensing region  41 Db. 
     In some embodiments, the algorithm can incorporate a delay that deactivates the sensor or otherwise prevents the dispenser from dispensing liquid immediately after the dispenser dispenses liquid. The delay may be may be for 1 second, 5 seconds, or any other amount of time. The delay helps prevent the user from unintentionally triggering the dispenser. For example, after the user triggers the dispenser to dispense liquid, the algorithm commands the sensor to deactivate for the delay period. During the delay period, the dispenser will not dispense liquid even if an object is in a sensing region during the delay period. If the user places his/her hand in a sensing region after the delay period, the dispenser will dispense liquid again. 
     In some embodiments, the one or more sensing regions  41 D can be used for allowing a user to select different modes of dispensing liquid L. When a signal is detected in the first sensing region  41 Da, the sensor  32 D triggers the dispenser  10 D to dispense a first predetermined volume of liquid L 1  in normal mode. In normal mode, the dispenser  10 D is configured to dispense a pre-determined volume of liquid L 1  suitable for washing a user&#39;s hands. When a signal is detected in the second sensing region  41 Db, the sensor  32 D triggers the dispenser  10 D to dispense liquid L in extended chore mode. In extended chore mode, the dispenser  10 D is configured to continuously dispense and/or an increased amount (e.g., a maximum predetermined amount of liquid). This may be helpful if, for example, the user wishes to fill a sink full of soapy water for washing dishes. In some embodiments, the volume of dispensed liquid does not depend solely or at all on the length of time that the object remains in the sensing region. In some embodiments, the dispenser  10 D may continue to dispense liquid as long as a hand is detected in second sensing region  41 Db. 
     In some embodiments, the dispenser  10 D may have a first and second sensing regions configured to operate in normal mode, and a third sensor region configured to operate in extended chore mode. 
     In some embodiments, the one or more sensing regions can be positioned in a manner that corresponds with natural human conduct or instinct. For example, a user may not want to place his/her hand underneath the nozzle to activate the extended chore mode if the user does not want soap on his/her hands. Thus, the sensing region associated with extended chore mode may be positioned above the upper portion of the dispenser  10 D or in proximity to the housing in an area that is not in the path of dispensed liquid. 
     In some embodiments, the dispenser  10 D includes an algorithm configured to send a command to trigger the dispenser to dispense liquid in normal mode, extended chore mode, or any other mode. For example, the algorithm can send a command to trigger the dispenser to dispense a liquid in normal mode if a signal is detected in a first sensing region  41 Da, or the algorithm can send a command to trigger the dispenser to dispense a liquid in extended chore mode if a signal is detected in the second sensing region  41 Db. 
     In some embodiments, the one or more sensing regions  41 D correspond with different types of dispensing liquid. For example, when a signal is detecting in the first sensing region  41 Da, the sensor  32 D triggers the dispenser  10 D to dispense a first type of liquid, such as soap. When a signal is detected in the second sensing region  41 Db, the sensor  32 D triggers the dispenser  10 D to dispense a second type of liquid, such as lotion. 
     In some embodiments, the dispenser  10 D includes an algorithm configured to send a command to trigger the dispenser to dispense different types of liquid based on the detected signal. For example, the algorithm can send a command to trigger the dispenser to dispense a first type of liquid, such as soap, if a signal is detected in a first sensing region  41 Da, or the algorithm can send a command to trigger the dispenser to dispense a second type of liquid, such as lotion, if a signal is detected in the second sensing region  41 Db. 
     In some embodiments, the dispenser  10 D only comprises one sensing region. The dispenser can be configured to dispense varying volumes of liquid, based on the signal detected in the sensing region. For example, the dispenser can dispense a first amount of liquid if the hand is positioned at a first angle in the sensing region, and the dispenser can dispense a second amount of liquid if the hand is positioned at a second angle in the sensing region. In another example, the dispenser can dispense a first amount of liquid if the hand performs a first motion in the sensing region, and the dispenser can dispense a second amount of liquid if the hand performs a second motion in the sensing region. 
     In some embodiments, the dispenser  10 D comprises a first sensing region and a second sensing region, and the dispenser is configured to dispense a predetermined volume of liquid, depending on the angle of the hand or the hand motion in a first sensing region or a second sensing region. 
     In some embodiments, the dispenser  10 D may comprise a mechanism to calibrate the different sensing regions with different output characteristics as desired by the user. For example, a user could configure a first sensing region to correspond with a first user-selected volume of liquid L 1  and configure a second sensing region to correspond with a second user-selected volume of liquid L 2 . In another example, the user could adjust the size (e.g., width or height) of the sensing region. The user could designate a first user-selected sensing region to correspond with a first pre-determined volume of liquid L 1  and designate a second user-selected sensing region to correspond with a second pre-determined volume of liquid L 2 . This calibration mode can be triggered by pressing a button, activating a sensor, or any other appropriate mechanisms. 
     In several embodiments, the dispenser  10 D includes an algorithm configured to send commands to the ECU when a signal indicates that an object is disposed in a sensing region. An example of such an algorithm is illustrated  FIG.  37   . The command may vary based on the signal received. The signal may be dependent on the distance between an object and the sensor, and/or other parameters such as angle, duration, repetition, path of motion, and/or speed of motion. In some embodiments, the algorithm can include a module  300  configured to dispense different volumes of liquid L. The module  300  may be configured to dispense different types of liquid, vary the duty cycle, or operate for varying durations. 
     Module  300  begins at start block  302 , and in operation block  304 , the module  300  initializes hardware and variables. In decision block  306 , the module  300  determines whether a signal has been received from a first sensing region. If a signal is detected in the first sensing region, the module  300  commands the dispenser to dispense a first amount of liquid L 1  as shown in operation block  308 . 
     If a signal is not detected in a first sensing region, the module  300  determines whether a signal has been received from a second sensing region in decision block  310 . If a signal is detected in a second sensing region, the module  300  commands the dispenser to dispense a second amount of liquid L 2  as shown in operation block  312 . 
     If a signal is not detected in a second sensing region, the module  300  determines whether a signal has been detected for extended chore mode in decision block  314 . In extended chore mode, the dispenser configured to dispense a predetermined maximum or at least an increased amount of liquid L 3 . In some implementations, the amount dispensed during a dispensation cycle is bounded by an upper dispensation limit, such as greater than or equal to about 20 ml. The module  300  does not need to include all of the blocks described above, or it may include more or different decision blocks, such as to account for more sensing regions or other parameters to detect. 
       FIG.  38    illustrates yet another embodiment of the previously discussed electrically operated soap dispenser  10 . In the illustrated embodiment, the electronically operated soap dispenser  10 E includes a pump unit  1001  and a cartridge  1002 . Some of the components of the dispenser  10 E can be the same, similar, or identical to the corresponding components of any of the other dispensers discussed above. As discussed previously with regard to the dispenser  10  the pump unit  1001  can include a pump, fluid dispensing valve, proximity sensor, and electronic components. The cartridge  1002  can be configured to be removable from the pump unit  1001 . In some embodiments, the cartridge  1002  can include a reservoir  1008  that contains soap to be dispensed by the pump unit  1001 . In some embodiments, the cartridge  1002  can include a reservoir  1008  and a power source  1003 , wherein the power source  1003  is configured to power the pump unit  1001 . 
     In the illustrated embodiment of  FIG.  38   , the cartridge  1002  can be configured to engage with a bottom portion of the pump unit  1001 . However, other configurations can be used, such as the cartridge  1002  configured to engage with a top or a side portion of the pump unit  1001 . The pump unit  1001  and the cartridge  1002  can include removably locking features (not illustrated) so that the cartridge  1002  removably engages with the pump unit  1001 . 
     In some embodiments, the pump unit  1001  can include a pump  1009  and a soap inlet  1004 , wherein the soap inlet  1004  can be configured to flow soap to the pump  1009 . In certain embodiments, the soap inlet  1004  can protrude out to engage with a valve  1005  of the cartridge  1002  so that the soap inlet  1004  and the valve  1005  are configured to be in fluid communications. The valve  1005  can be a one-way valve so that the soap is designed to flow to the pump unit  1001  and not leak in other directions. Of course, other engagement configurations can be used where the soap inlet  1004  is a recess and the valve  1005  protrudes. 
     In some embodiments, the valve  1005  can include a seal that initially seals the valve  1005  of the cartridge  1002 . In some embodiments, the seal is punctured by the soap inlet  1004  when the cartridge  1002  engages the pump unit  1001  so that the soap inlet  1004  and the valve  1005  can be in fluid communication. The seal can be incorporated with the valve  1005 . The engagement of the cartridge  1002  and the pump unit  1001  can be guided so that the soap inlet  1004  and the valve  1005  are generally aligned and the seal is easily broken. 
     In some embodiments, the cartridge  1002  can include the reservoir  1008  for soap and the power source  1003 . The power source  1003  can be a disposable power source, such as a battery. The power source  1003  can include electrical contacts  1006  that engage with pump unit electrical contacts  1007  to complete a circuit and provide power to the pump unit  1001 . The electrical contacts  1006  and  1007  can be traditional battery contacts such as electrically conducting springs, plates, etc. The pump unit  1001  can be powered off when the cartridge  1002  is disengaged. 
     In some embodiments, the amount of soap and the stored power within the power source  1003  can be designed to be exhausted at about the same time. The time to exhaust the soap and the power source  1003  can be from about 3 months to about 12 months during normal use (operations of the about 10 times a day) of the dispenser  10 E. In some embodiments, the amount of soap dispensed by the dispenser  10 E is fixed so that the number of dispenses of soap from the reservoir  1008  is known. The amount of electric capacity within the power source  1003  can then be configured to be exhausted at about the same time as the amount of soap in the reservoir  1008 . In some embodiments, the amount of soap dispensed can be varied and the amount of soap and the power within the power source  1003  can be exhausted at different times. The user replaces the cartridge  1002  when either the soap or power source  1003  (or both) is exhausted. The simple replacement of the cartridge  1002  allows the user from having to manually replenish the soap or having to replace the batteries in the dispenser  10 E, which occur most likely at different times. 
     With reference to  FIGS.  39 - 44   , another embodiment of a dispenser is identified generally by the reference numeral  1110 . The dispenser  1100  can include a housing portion  1112 , which in turn can include a reservoir  1116 , a pump  1118 , and a nozzle  1128 . In some embodiments, a sensor  1132  is positioned on the housing portion, for example, near the nozzle  1128  as shown in  FIG.  42    or any other position described herein. Some of the components of the dispenser  1110  can be the same, similar, or identical to the corresponding components of the dispensers discussed above. 
     As discussed above, in several embodiments the dispenser  1100  can include a lid  1122 , as shown in  FIG.  39   , which can be configured to form a seal at the top of the reservoir  1116  for maintaining the liquid soap L within the reservoir  1116 . In some embodiments, the lid  1122  can include an air vent (not shown), which can allow air to enter the reservoir  1116  as the level of liquid soap L falls within the reservoir  1116  such as during the course of use of the dispenser  1100 . In some embodiments, the lid  1122  can be movable but generally non-removable from the dispenser  1100 . For example, the lid  1122  can be a pivotable, as shown in  FIG.  43   . A non-removable lid can be desirable as it can reduce the chance that the user will misplace the lid. When the lid  1122  is moved to an open position, the user can refill the reservoir  1116 . A portion of the lid  1122  may include an engagement member, such as protruding portion  1138  that engages (e.g., snaps together) with a recess  1134 , to keep the lid  1122  from opening unintentionally. The protruding portion  1138  may be offset or protrude from the outer edge  1136  of the lid, so the user can readily manipulate (e.g., push or pull on the outer edge  1136  of the lid). In some embodiments, the lid  1122  may be opened with the press of a button or by triggering a sensor. 
     In certain embodiments, the lid  1122  can be biased (e.g. by a spring). For example, in some embodiments, the lid  1122  can be biased toward the open position. In some variants, the lid can be biased toward the closed position. In certain embodiments, the lid can be configured to open when a user pushes on the lid  1122 . In some embodiments, the reservoir  1116  can include an opening  1135  configured to be partly or entirely covered by the lid  1122 . Some embodiments of the opening  1135  can be configured to facilitate loading of liquid soap L into the reservoir  1116  via the opening  1135 . For example, the opening  1135  can have a first dimension D 1  (e.g., generally parallel with the front of the dispenser  1110 ) that is greater than or equal to a second dimension D 2  (e.g., generally perpendicular to the front of the dispenser  1110 ). In some embodiments, the first diameter D 1  or widest dimension of the opening  1135  is at least about 1 inch, about 2 inches, or about equal to the length of a frontward edge  1137  ( FIG.  44   ). In some embodiments, as illustrated, the lid  1122  encompasses less than the entire top surface of the dispenser  1110 , such as less than or equal to about half of the top surface of the dispenser. In some embodiments, the lid  1122  can have at least a portion that corresponds to an outer shape (e.g., a curve) of the top region or other adjacent portion of the dispenser  1110 , and/or the lid  1122  has at least a portion (e.g., a generally straight line) that does not correspond to an outer shape of the top region or other adjacent portion of the dispenser  1110 . 
     As noted above, in several embodiments, the dispenser  1110  can include a processor, which can control and/or report, by various components, schemes, and algorithms, input and output characteristics and functions of the dispenser  1110 . In some embodiments, as shown in  FIG.  42   , one or more wires  1120  can carry signals between, for example, the processor and the sensor  1132 . In some variants, based on the signal received from the sensor, the processor can signal the pump  1118  to dispense different volumes of liquid soap L, activate different duty cycle characteristics, increase or decrease the dispensation speeds, operate for greater or lesser durations of time, or other appropriate parameters. 
     In some embodiments, the dispenser  1110  can include a user input device  1152 , such as a button, dial, switch, or otherwise. The user input device  1152  can provide a signal to the processor, such as to manually operate the dispenser  1110  to continuously discharge or discharge larger amounts of liquid soap L when desired. For example, if a user of the dispenser  1110  wishes to fill a sink full of soapy water for washing dishes, the user can simply push the user input device  1152  and dispense a larger amount of soap than would normally be used for washing one&#39;s hands, such as at least about 3 milliliters or at least about 4 milliliters. In certain configurations, the input device  1152  can have a generally low profile. For example, an upper surface of the user input device  1152  can be flush or about flush with an upper surface of the lid  1122  when the lid  1122  is closed. In some embodiments, the surface area of the upper surface of the user input device  1152  can be greater than or equal to the surface area of the upper surface of the lid  1122 , which can provide for ready manipulation of the user input device  1152 . 
     In some embodiments, the dispenser  1110  can include memory, such as firmware, to store the various control schemes and algorithms, as well certain instructions and/or settings related to various characteristics of the dispenser  1110 . For example, the memory can include instructions and/or settings regarding the size of the sensing regions, the sensitivity of the sensors, the volume and/or rate of liquid soap dispensed, duty cycle characteristics, the length of various timers, and otherwise. 
     In some embodiments, the dispenser  1110  can include a power adjustment device, such as a button  1131 . In some implementations, alternatingly toggling (e.g., pressing) the button  1131  energizes and de-energizes the dispenser  1110 . In some variants, momentary toggling of the button  1131  results in the dispenser  1110  entering a lower power consumption mode, which can enhance the life of the power source. 
     In several embodiments, the dispenser  1110  can include a port  1130 , such as a universal serial bus (USB) port, as shown in  FIG.  40   . The port  1130  can be configured to permanently or removably receive a connector coupled with a wire or cable (not shown). In some embodiments, the port  1130  is configured to allow electrical potential to pass to a soap dispenser power source via the connector. In some embodiments, the port is configured to facilitate charging or recharging of the soap dispenser power source. 
     In some embodiments, the dispenser  1110  can be configured such that a user can modify (e.g., update, program, or otherwise) the memory, such as by connecting the dispenser  1110  to a computer. In some embodiments, the dispenser  1110  can be communicatively connected with a computer via the port  1130  (e.g., using a USB/cable). In certain instances, data can be transferred between the computer and the dispenser  1110  via the port  1130 . In some embodiments, the dispenser  1110  is configured to communicate with a computer wirelessly, such as by a cellular, Wi-Fi, or Bluetooth® network, infrared, or otherwise. 
     In some embodiments, when the dispenser  1110  is in communication with the computer, a control panel may be displayed on a display device associated with the computer. The control panel may allow the user to adjust various input and output characteristics for the dispenser  1110 . For example, in some embodiments, a user can use the control panel to adjust the volume of liquid soap dispensed from nozzle  1128 . In certain embodiments, the dispenser  1110  can include first and second sensing regions and the user can configure the volumes of liquid soap associated with the first and second sensing regions. In some examples, the user can adjust the size (e.g., depth, width, and/or height) of one or more of the sensing regions. In some implementations, the user can use the control panel to modify the operation and output (e.g., volume or rate) of soap dispensed based on certain conditions, such as the amount of battery power remaining, the amount of liquid soap estimated to be remaining in the reservoir  1116 , and otherwise. In certain variants, the ability to modify the operational parameters of the dispenser  1110  with the control panel can reduce or obviate the need for one or more adjustment devices (e.g., buttons, knobs, switches, or the like) on the dispenser  1110 , thereby providing a generally uniform exterior surface of dispenser  1110  (which can facilitate cleaning) and reducing the chance of unintentional adjustment of the operational parameters (such as when transporting the dispenser  1110 ). 
     In some embodiments, when the dispenser  1110  is in communication with the computer, data can be transferred from the dispenser  1110  to the computer. For example, in some embodiments, the dispenser  1110  can transfer data, such as power consumption, estimated remaining battery power, the number of activations of the dispenser  1110 , rate, amount, and/or frequency of soap consumption, and otherwise. In certain embodiments, software can be used to analyze the transferred data, such as to calculate usage statistics (e.g., during specific periods), recognize and/or draw attention to unusual activity, and produce graphical representations of the data (e.g., charts, graphs, or the like). Transferring usage statistics from the dispenser  1110  to the computer can allow the user to monitor usage and enables the user to calibrate different characteristics of the dispenser  1110  (e.g., based on previous usage and parameters). In certain embodiments, transferring data from the dispenser  1110  to the computer can reduce or avoid the need for one or more adjustment or display devices on the dispenser  1110  itself. 
     In some embodiments, when the dispenser  1110  is in communication with the computer, the dispenser  1110  can transfer data to the computer and the computer transfers data to the dispenser  1110 . Furthermore, in some embodiments, when the dispenser  1110  is in communication with the computer, electrical potential can be provided to the soap dispenser power source before, during, or after such two-way data transfer. The electronic interfacing, control, and/or reporting described herein in connection with the dispenser can be used with many other electrical devices, including houseware devices, such as trashcans, mirrors, cooking devices (e.g., ovens, stones, toasters, etc.), refrigerators, etc. 
     With reference to  FIGS.  45 - 54   , another embodiment of a dispenser is identified generally by the reference numeral  1210 . The dispenser  1210  can include a lower portion  1213   b , an upper portion  1213   a , a reservoir  1216 , and dispensing portion  1227  with a nozzle  1228 . In some embodiments, a sensor  1232  can be positioned on the dispenser  1210 , for example, on the bottom portion of the dispensing portion  1227  as shown in  FIG.  46   . In several embodiments, the lower portion  1213   b  comprises the reservoir  1216 . In some embodiments, the entire lower portion  1213   b  can be the reservoir  1216 . The reservoir  1216  can be configured for disposable, one-time use with a temporarily sealed soap-containing portion that is discarded when the soap supply is exhausted. Some of the components of the dispenser  1210  can be the same, similar, or identical to the corresponding components of the dispensers discussed above. 
     In some embodiments, the upper portion  1213   a  comprises a lid  1222  configured to open to allow access to the reservoir  1216  (e.g., for adding liquid soap L to the reservoir  1216 ) and to close (e.g., for maintaining the liquid soap L within the reservoir  1216 ). In some embodiments, the lid  1222  can be pivotable. For example, in some embodiments, the lid  1222  can be pivotable about an axis generally parallel to the front of the dispenser  1210 . The lid  1222  may be opened by any of the mechanisms discussed above, such as by pushing or pulling on the lid  1222 , pressing a button, triggering a sensor, or otherwise. 
     In several embodiments, the upper portion  1213   a  comprises some or all of the components that draw, pump, dispense the soap, and/or that power and control the dispenser  1210 . For example, in certain variants, the upper portion  1213   a  can include the nozzle  1228 , the sensor  1232 , a pump  1218 , a conduit  1226 , a power supply, an actuator, and/or an electronic control unit. As shown in  FIG.  46   , a cover  1240  can partly cover certain components, such as the pump  1218 , power supply, actuator, and/or electronic control unit. As described above, the electronic control unit may comprise control circuits, a processor, and memory devices for storing and performing control routines. 
     In some embodiments, the dispenser  1210  can include a user input device  1252 , such as a button, dial, switch, or otherwise. The user input device  1252  can provide a signal to the processor, such as to manually operate the dispenser  1210  to continuously discharge or discharge larger amounts of liquid soap L when desired. For example, if a user of the dispenser  1210  wishes to fill a sink full of soapy water for washing dishes, the user can simply push the user input device  1252  and dispense a larger amount of soap than would normally be used for washing one&#39;s hands, such as at least about 3 milliliters or at least about 4 milliliters. In certain configurations, the input device  1252  can have a generally low profile. For example, an upper surface of the user input device  1252  can be flush or about flush with an upper surface of the lid  1222  when the lid  1222  is closed. In some embodiments, the surface area of the upper surface of the user input device  1252  is greater than or equal to the surface area of the upper surface of the lid  1222 , which can provide for ready manipulation of the user input device  1252 . 
     As illustrated in  FIGS.  46 A-B , in some embodiments, the upper portion  1213   a  and the lower portion  1213   b  can detach from each other. In several embodiments, it may be desirable to have a detachable reservoir  1216 . For example, the detachable reservoir  1216  can allow the user to replace the lower portion  1213   b  with a new, fresh, or pre-filled lower portion  1213   b . For example, a user may purchase several lower portions  1213   b , which may be pre-filled with liquid soap. When a particular lower portion  1213   b  has been spent (e.g., the soap of the lower portion  1213   b  has been consumed) then the user may remove the upper portion  1213   a  from the used lower portion  1213   b  and engage the upper portion  1213   a  with an unused or at least not empty lower portion  1213   b , thereby providing a generally uninterrupted supply of soap. As some embodiments house the components for pumping and dispensing soap in the upper portion  1213   a , the same upper portion  1213   a  can be used again and again with various lower portions  1213   b . Further, the arrangement of having the components for pumping soap in the upper portion  1213   a  can provide a convenient assembly (e.g., a single generally contained unit) to move between lower portions  1213   b . Thus, certain embodiments can allow users to replenish the liquid soap L without pouring any liquid soap L out of a container and potentially creating a mess. In some embodiments, the dispenser can indicate (such as visibly or audibly, by a light or a speaker) that the soap supply has diminished to a pre-determined level so that a new disposable portion, pre-filled with soap can be purchased in the near future. 
     In several embodiments, it may be desirable to have a dispenser  1210  with a detachable lower portion  1213   b , as shown in  FIG.  55   . In some embodiments, the lower portion  1213   b  comprises a reservoir  1216  configured to receive liquid soap L. In these embodiments, the user is able to replace the lower portion  1213   b  when the soap is exhausted. In certain scenarios, it may be desirable to position the reservoir  1216  in a lower portion of the dispenser  1210 , so the reservoir  1216  is easier to access and replace. 
     In some embodiments, the lower portion  1213   b  includes a power source. In some embodiments, the power source can be disposable. In some embodiments, the power source comprises one or more batteries. In certain variants, the batteries are charged by, an electrical connection to a domestic power supply, such as a standard wall outlet. The power source can include electrical contacts that engage with the upper portion  1213   a  to complete a circuit and provide electrical power to the dispenser  1210 . In some embodiments, the dispenser  1210  can be de-powered when the upper and lower portions  1213   a ,  1213   b  are disengaged. 
     In several embodiments, the lower portion  1213   b  can be configured to engage with the upper portion  1213   a . The upper portion  1213   a  and lower portion  1213   b  can include engagement features configured to maintain the lower portion  1213   b  in engagement the upper portion  1213   a . For example, one or both of the upper and lower portions can include mating tabs and slots, ball detents, or otherwise. As illustrated, the outer shape and contours of the lower portion  1213   b  can generally correspond to the outer shape and controls of the upper portion  1213   a.    
       FIGS.  51 - 54    illustrate an embodiment of the pump  1218 . In several embodiments, the pump  1218  can be a gear pump and can comprise a pair of gears  1270  and a pump body  1272 . In some embodiments, other type of pumps can be used, such as diaphragm pumps, centrifugal pumps, etc. In some embodiments, the pump  1218  can include an inlet and an outlet. The inlet can connect to a conduit  1226   b  for receiving liquid soap L from the reservoir  1216 . The outlet can connect to a conduit  1226   a  for delivering liquid soap L to the nozzle  1228   d . In some embodiments, as shown in  FIGS.  49 - 50   , liquid soap L is encouraged out of the pump  1218  in generally a vertical pathway from the conduit  1226   a . In some embodiments, the soap dispenser  1210  can be taller than it is wide (e.g., front to back), thus horizontal space may be more at a premium than vertical space. Accordingly, in certain variants, arranging the liquid soap to exit via a connector  1271  that extends generally vertical can provide a more efficient use of space compared to embodiments having a connector that extends generally horizontally. In some embodiments, the generally vertically extending connector  1271  may be desirable to help decrease the size of the soap dispenser  1220 . 
     In several embodiments, when the upper portion  1213   a  is engaged with the lower portion  1213   b , conduit  1226   b  extends into the liquid soap L in reservoir  1216 . The conduit  1226   b  can be configured such that an end of the conduit  1226   b  is positioned at or near the bottom of the lower portion  1213   b  when the upper and lower portions are coupled together. In this configuration, the pump  1218  can be disposed generally above the liquid soap L. The pump  1218  drives liquid soap L from the reservoir, through the pump  1218 , and out of the nozzle  1228 . 
     With reference to  FIG.  55   , another embodiment is illustrated with a removable fluid-containing cartridge. As with other embodiments disclosed herein, the features, structures, steps, and/or processes of the embodiments of  FIG.  55    and related disclosure can be used in addition to or instead of those in other embodiments, such as the embodiment shown in  FIG.  38   . Some dispensers include a pump unit  1001  and a removable cartridge  1002 . In some embodiments, the cartridge can be configured to be disposable, such as after a single use or after the use of a certain volume of soap. 
     In some embodiments, the dispenser can be replenished by replacing or at least partially refilling the cartridge. For example, when a fluid volume of liquid (e.g., liquid soap) in a first cartridge is exhausted or at least drops below a limit, then the first cartridge can be removed and/or replaced with a second cartridge. In some variants, when the first cartridge includes a power source, such as a battery, and can be replaced when a condition occurs (e.g., a certain number of dispensations has occurred, the amount of power remaining in the power source is determined to be below a limit, etc.). 
     The cartridge  1002  can be configured to engage with the pump unit  1001  in various configurations. For example, the cartridge  1002  can engage a bottom portion of the pump unit  1001  (see  FIG.  38   ), a top portion of the pump unit  1001  (see  FIG.  55   ), or any other portion or combination of portions of the pump unit  1001 , such as the front, rear, and/or side. The cartridge  1002  can engage the pump unit  1001  using any type of removable connection, such as with magnets, clips, snaps, a screw-fit, an interference fit, one or more spring-loaded buttons or sliders, or otherwise. In some embodiments, the cartridge  1002  or pump unit  1001  can includes one or more first attachment structures such as arms, fins, ribs, struts, detents, bosses, or the like that are configured to be received in corresponding second attachment structures such as recesses, notches, grooves, or the like in the other of the cartridge  1002  and pump unit  1001 . Generally, the cartridge  1002  engages the pump unit  1001  such that a fluid or a liquid, and/or electrical power, can flow from the cartridge  1002  and into the pump unit  1001 . 
     In some embodiments, the cartridge  1002  contains at least one fluid, such as soap, lotion, and/or sanitizer. In certain implementations, the cartridge  1002  can include a power source, such as a battery. Some variants of the cartridge  1002  can indicate one or more properties of the cartridge  1002  contents to the pump unit  1001 . For example, in some embodiments, the cartridge  1002  can indicate the contents of the cartridge  1002  (e.g., the type of fluid: soap, lotion, sanitizer, etc.). In certain implementations, the cartridge  1002  can indicate one or more characteristics of the contents of the cartridge  1002 , such as the brand of the fluid, the viscosity of the fluid, the moisture content of the fluid, the volume of the fluid contained, and/or battery capacity (e.g., beginning and/or real-time voltage or current of the power source). For example, in some embodiments, the cartridge  1002  can indicate that it contains about 100 milliliters of liquid hand soap and a power source with about 15 watts of power (e.g., about 1.5 volts and about 10 amps). In some implementations, the cartridge  1002  can indicate to the pump unit  1001  whether the cartridge  1002  is for home, commercial, or industrial use. The soap pump  1001  can be configured with a display for showing the user one or more characteristics of the fluid or the soap pump  1001  can be configured to obtain the information for internal processing without displaying the information to a user. 
     In certain variants, the pump unit  1001  and/or the cartridge  1002  can have an engagement indication element (not shown), such as an internal indicator in electrical communication with a processor in the pump  1001  or an external indicator, such as a speaker, a colored window, a moveable indicating component, a light, etc. The engagement indication element can be configured to signify that the pump unit  1001  and the cartridge  1002  have been properly engaged. Some variants of the engagement indication element can be configured to indicate that data regarding the cartridge  1002  has been received by the pump unit  1001 . 
     Some embodiments of the pump unit  1001  can be configured to detect the cartridge  1002 . For example, the pump unit  1001  can include a sensing element (not shown) that is configured to detect the cartridge  1002  when the cartridge  1002  and the pump unit  1001  are engaged. In some embodiments, the sensing element can be configured to detect one or more detection characteristics such as: a magnetic field, capacitance, resistance, a particular electrical voltage or current or a particular range or pattern of voltages or currents, conductivity, pressure, vibration, sound, light, or otherwise. For example, the sensing element can be configured to detect the strength presence and/or strength of a magnetic field emanating from the cartridge  1002 . In certain variants, the sensing element can be configured to detect patterns of light, or disruptions thereof, when the cartridge  1002  is engaged with the pump  1001 . In certain variants, the pump  1001  can be configured to receive an indication of a feature of the cartridge  1002  and to change a characteristic (e.g., output) of the configuration and/or performance of the pump unit  1001  based at least in part on that indication. 
     In certain implementations, the sensing element can be configured to detect the engagement of the pump unit  1001  with one or more mechanical or electrical indication members of the cartridge  1002 . For example, in some embodiments, the combination of the pump unit  1001  and the cartridge  1002  comprises an engagement system, such as one or more receiving members, such as recesses, slots, or otherwise, on one of the pump unit  1001  or cartridge  1002  that are configured to engage with a series of projection members, such as clips, pins, ribs, or otherwise, on the other of the pump unit  1001  or cartridge  1002 . 
     In some embodiments, the sensing element can comprise a mechanical configuration or array to provide an indication of one or more characteristics of the cartridge  1002 . In some implementations, the number, type, position, shape, arrangement, orientation, and/or other characteristics of the mechanical configuration or array (e.g., projection members) can be used to discern one or more characteristics of the cartridge  1002  and/or the contents thereof. For example, with reference to the embodiments of  FIGS.  56 A- 56 C , the sensing element comprises a plurality of slots, such as three slots, A, B, and C, and the cartridge  1002  comprises a plurality of pins, such as two pins X, Y configured to engage two of the slots. As shown in  FIG.  56 A , a first characteristic of the cartridge  1002  and/or the contents thereof can be discerned when the pins X, Y engage slots A and B. As illustrated in  FIG.  56 B , a second characteristic of the cartridge  1002  and/or the contents thereof can be discerned when the pins X, Y engage slots B and C. As shown in  FIG.  56 C , a third characteristic of the cartridge  1002  and/or the contents thereof can be discerned when the pins X, Y engage slots A and C. 
     In some embodiments, the cartridge  1002  comprises electrical contacts that can engage with corresponding electrical contacts of the sensing element of the pump unit  1001 , thereby allowing for one or more characteristics of the cartridge  1002  to be determined based on which of the corresponding electrical contacts are engaged. In some embodiments, the sensing element can comprise electronic circuitry configured to produce one or more electronic signals, such as a specific resistance value in the cartridge or a specific voltage or current output (including a range of outputs) generated by a power source in the cartridge, that can be sensed by the pump unit  1001  upon engagement therewith to determine one or more characteristics of the cartridge  1002 . For example, a first electronic characteristic, such as a first resistance value or voltage or current value (e.g., 100 ohms, 1 volt, or 5 amps), can indicate a first characteristic (e.g., the cartridge contains soap), and a second electronic characteristic, such as a second resistance value or voltage or current value (e.g., 300 ohms, 5 volts, or 10 amps), can indicate a second characteristic (e.g., the cartridge contains a hand sanitizer), etc. There can be any number of electronic signals correlated to different cartridge characteristics (e.g., at least 2, at least 3, etc.). 
     In some embodiments, the pump unit  1001  contains memory, such as firmware. The memory can contain subroutines for performing any of the processes or steps disclosed herein and/or data, such as a cross-reference, that can be used to determine what the various cartridge  1002  indications represent in terms of the characteristics of the contents of the cartridge  1002  (e.g., fluid type, volume, power source voltage, and otherwise). For example, in the embodiments of  FIGS.  56 A- 56 C , when pins X, Y are found to engage slots A and B, the memory could be accessed to determine that such a configuration indicates that the cartridge contains a predetermine quantity of liquid hand soap; when pins X, Y are found to engage slots B and C, the memory could be accessed to determine that such a configuration indicates that the cartridge contains a different predetermined quantity of liquid hand soap; and when pins X, Y are found to engage slots A and C, the memory could be accessed to determine that such a configuration indicates that the cartridge contains a predetermined quantity of lotion. 
     In some embodiments, one or more of the output characteristics of the pump unit  1001  can be adjusted based on, in whole or in part, the indication from the cartridge  1002  to the pump unit  1001 . For example, the dispensation volume, dispensation period, motor duty cycle, pumping pressure, operational voltage, and/or other characteristics can be adjusted based on the indication of the cartridge  1002  to the pump unit  1001  regarding one or more characteristics of the contents of the cartridge  1002 . For example, in some implementations, if the cartridge  1002  is determined to contain a first type of fluid (e.g., liquid soap), then the pump unit  1001  can be automatically adjusted to dispense a first volume (e.g., about 1.0 milliliter) of the first fluid when the pump unit  1001  is activated. In some variants, if the cartridge  1002  is determined to contain a second fluid that is different from the first fluid (e.g., lotion), then the pump unit  1001  can be adjusted to dispense a second volume that is different from the first volume (e.g., 2.0 milliliters) of the second fluid when the pump unit  1001  is activated. In some embodiments, the output characteristic adjustments can be contained in the memory of the pump unit  1001 . For example, when the memory is accessed to determine the contents of the cartridge  1002 , the memory can be accessed to determine what adjustments to the pump unit  1001  should be made for such contents. In some embodiments, a manual adjustment of a characteristic (such as liquid dispensing volume control) is not required when an automatic adjustment of that characteristic is performed. 
     In certain embodiments, the output characteristics of the pump unit  1001  can be adjusted based on the viscosity of the fluid contained in the cartridge  1002 . For example, in some variants, the pumping pressure and/or amount of power applied to the motor can be changed as a function of the viscosity of the fluid contained in the cartridge  1002 . For example, when the pump unit  1001  determines that the cartridge  1002  contains a first fluid (e.g., a liquid soap) with a first viscosity, the pump unit can adjust the motor&#39;s duty cycle to a first setting (e.g., 60%), and when the pump unit  1001  determines that a second cartridge  1002  contains a second fluid (e.g., a second type of liquid soap) with a second viscosity (e.g., different than the first viscosity), the pump unit can adjust the motor&#39;s duty cycle to a second setting that is different from the first setting (e.g., 80%). In certain variants, the pump unit can be programmed to increase the volume of fluid dispensed or to dispense liquid for a longer period of time, such as by increasing the number of duty cycles of the motor. 
     In some embodiments, the pump unit  1001  and/or the cartridge  1002  can be configured such that the power source (e.g., one or more batteries) and the fluid contents are exhausted at about the same time. Thus, the cartridge  1002  can be discarded with little or no unused fluid and/or power reserve. Such a configuration can, for example, promote efficiency by reducing the amount of fluid and/or power reserve that is unused yet discarded. 
     In certain implementations, the amount of fluid in the cartridge  1002  is described as a “fluid rating,” which is a percentage of the initial fluid level remaining in the cartridge. In some variants, the amount of power in the cartridge  1002  is described as a “power rating,” which is a percentage of the initial amount of power remaining in the power source. Generally, the cartridge  1002  initially includes a 100% fluid rating and a 100% power rating. In some embodiments, after half of the fluid and half of the power have been expended, the cartridge  1002  has a 50% fluid rating and a 50% power rating. In certain implementations, the cartridge  1002  can be configured such that the fluid rating and the power rating decrease approximately in unison. In some embodiments, the cartridge  1002  can be configured such that the fluid rating and the power rating are proportionally related. In some embodiments, the fluid rating and the power rating each decrease in a generally linear manner. 
     Certain variants have a fluid rating and power rating that decrease at different rates. Such a configuration can be beneficial, for example, in embodiments in which the amount of power needed to expel an amount of fluid increases as the fluid rating decreases (e.g., to overcome head pressure, gravity, friction, or otherwise). In some embodiments, the cartridge  1002  can be configured such that the fluid rating reaches approximately 0% before the power rating reaches approximately 0%, thereby providing a small reserve of power for expelling the last of the fluid. In certain implementations, the fluid rating decreases in a generally linear manner and the power rating decreases in a generally exponential manner. In some variants, the fluid rating and the power rating each decrease in generally linearly, but with different slopes. 
     In some embodiments, the pump unit  1001  can be programmed with different settings for the same cartridge contents. For example, the dispenser may include one or more sensing regions similar or identical to the sensing regions discussed in reference to  FIGS.  33 - 36   . If a signal is detected in a sensing region, the sensor can trigger the dispenser to perform a specific operation based on the particular signal. For example, the specific operation may vary based on the distance between a hand H and the sensor, and/or other parameters such as angle, duration, repetition, path of motion, and/or speed of motion. The different settings can be activated using different input or selector devices, such as buttons, knobs, or other devices. The settings triggered by the sensor or input device can change depending on the type of cartridge  1002  connected to the pump  1001 . 
     The dispenser can include one or more indicators configured to issue a visual, audible, or other type of indication to a user of the dispenser. For example, the dispenser may indicate the type (e.g., soap or lotion) of dispensing fluid contained in the cartridge  1002 , the actual or estimated volume of dispensing fluid remaining in the cartridge  1002 , or otherwise. Certain embodiments are configured to indicate the actual or estimated power source voltage, remaining capacity, life expectancy (e.g., in terms of time or number of dispensations), or otherwise. 
     In some embodiments, the soap dispenser can include a controller (e.g., a processor) configured to implement one or more algorithms. The algorithms can be configured to send commands to control one or more aspects of the liquid dispenser, such as one or more commands to dispense the fluid from the cartridge  1002  according to the discerned characteristics of the cartridge  1002 . An example of such an algorithm is illustrated in  FIG.  57   . Beginning at start block  1302 , in operation block  1304 , the module  1300  initializes hardware and variables. The algorithm can then proceed to decision block  1306 , in which the module  1300  determines whether a cartridge  1002  is connected to the pump unit  1001 . Next, in decision block  1308 , the module  1300  can determine whether the sensing element of the pump unit has determined that the cartridge  1002  contains a first feature (e.g., a particular type of liquid soap) L 1 . If L 1  is detected, then, in operation block  1310 , the module  1300  can initiate output characteristics pre-programmed for feature L 1 . For example, the pump unit  1001  can set the soap dispensation time and/or volume of to a level appropriate for L 1 . The adjusted output characteristics may include any combination of output characteristics described above. The algorithm can then return to block  1306  to repeat the logic loop. If L 1  is not detected, then the algorithm can proceed to decision block  1312 , in which the module  1300  can determine whether the cartridge  1002  contains a second feature L 2  (e.g., a different type of liquid than L 1 , such as lotion or hand sanitizer). If L 2  is detected, then, in operation block  1314 , the module  1300  can initiate output characteristics pre-programmed for liquid L 2 . For example, the pump unit  1001  can set the liquid dispensation time and/or volume to a level appropriate for L 2 . As shown, the algorithm can then return to block  1306  to repeat the logic loop. Module  1300  does not need to include all of the blocks described above, or it may include more or different blocks to account for additional and/or different features (e.g., fluid viscosity, fluid volume, power supply type and/or voltage, cartridge life expectancy and/or expiration, or otherwise). 
     Although the soap dispenser has been disclosed in the context of certain embodiments and examples, it will be understood by those skilled in the art that the soap dispenser extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the embodiments and certain modifications and equivalents thereof. For example, some embodiments can be configured to use a fluid other than soap, e.g., hand sanitizer, shampoo, hair conditioner, skin moisturizer or other lotions, toothpaste, or other fluids. It should be understood that various features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the soap dispenser. Accordingly, it is intended that the scope of the soap dispenser herein-disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow.