Abstract:
A hybrid faucet system can include one or more sensors and manual controllers. For example, a faucet system can include a first infrared sensor configured to communicate with processing electronics to initiate a first operating mode of a hybrid faucet responsive to detecting a first activation motion for a first time period. The system can include a first manual controller configured to control a flow rate of hot water into the hybrid faucet system. In some embodiments, the system includes a second manual controller configured to control a flow rate of cold water into the hybrid faucet system.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 62/239,205, filed Oct. 8, 2015, titled TOUCH-FREE FAUCETS AND SENSORS. The entire contents of the above-identified patent application is incorporated by reference herein and made a part of this specification. 
     
    
     BACKGROUND 
       [0002]    Field 
         [0003]    Certain embodiments disclosed herein relate to touch-free faucets and sensors configured for simplified installation and/or relate to touch-free faucets configured to support multiple modes of operation. In particular, embodiments disclosed are particularly useful for controlling an attribute for water flowing from a faucet and/or for faucets and other objects with limited installation zones or requiring targeted sensors, including components of such sensors, and methods for manufacturing touch-free sensor equipped devices. 
         [0004]    Description of the Related Art 
         [0005]    Touch-free sensors can enable the operation of objects without the need for directly touch them. For example, touch-free faucets can provide a more hygienic means of washing hands and performing other tasks associated with traditional faucets. Touch-free faucets and faucets with touch-free operations typically include one or more sensors for sensing the presence of an object in a detection area for controlling an operation of the faucet. There remains a need for improvements to such sensors and the methods currently employed to install them. 
       SUMMARY 
       [0006]    Certain aspects, advantages and novel features of embodiments of the invention are described herein. It is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment of the invention disclosed herein. Thus, the invention disclosed herein may be embodied or carried out in a manner that achieves or selects one advantage or group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein. Though primarily disclosed in the context of a faucet, other assemblies can utilize the disclosed sensor assemblies. 
         [0007]    Some embodiments of a hybrid faucet system include one or more sensors and one or more manual controllers. The manual controllers may include levers, knobs, handles, and other manual input structures. The sensors can include infrared sensors, motion sensors, and/or light sensors. Various functions of the hybrid faucet system, such as overall flowrate, hot water flow rate, cold water flow rate, ON/OFF, and/or other functions may be controlled by one or both of a sensor and a manual controller. For example, in some embodiments, the ON/OFF function of the faucet system is controlled via a sensor while the hot and cold flow rates are controlled by manual controllers. 
         [0008]    Some embodiments provide a method of manufacturing a faucet including inserting a sensor into a sensor mounting hole of the faucet body from the outside. Some embodiments include an emitter, a detector, and an electronic circuit board that can be simultaneously inserted through the sensor mounting hole. A flange can be included on the sensor to mount flush with the faucet body. 
         [0009]    In some embodiments, a hybrid faucet includes a faucet housing, two mechanical valves, an electronic control valve (e.g., solenoid valve), two electronic sensors (e.g., infrared sensors), a visible LED for indication, a logic processor and/or a power supply unit. A first mechanical valve with cylinder stem can be located upstream of the electronic control valve to control the cold and hot water ratio and mix the hot and cold water to a desired water temperature. A second mechanical valve with cylinder stem can control water flow rate. One or more sensors can control various features of the faucet. For example, one sensor can control intermittent water flow. A second sensor can control a faucet continuous water mode. A logic processor can detect signals from sensors. The logic processor can send output signals to an electronic control valve such as a solenoid valve to turn on/off water flow. A power source can power the logic processor. Accordingly, water flow can be controlled by the sensors without touching the faucet housing. 
         [0010]    In some embodiments, a hybrid faucet includes a faucet housing, two mechanical valves, an electronic control valve (e.g., solenoid valve), two sensors (e.g., infrared sensors), a visual LED for indication, a logic processor, and/or a power supply unit. A first mechanical valve with cylinder stem can be located upstream of an electronic control valve to control the cold and hot water ratio and mix the hot and cold water to a desired water temperature. The hybrid faucet can include a second mechanical valve with cylinder stem on the same axis of the first mechanical valve cylinder stem and upstream of the electronic control valve to control water flow rate. One of the sensors can control a faucet intermittent water flow mode. Another sensor can control a faucet continuous water flow mode. 
         [0011]    In some embodiments, a hybrid faucet includes a faucet housing, one or more mechanical valves, an electronic control valve, one or more sensors (e.g., infrared sensors), a visual LED for indication, a logic processor, and/or a power supply unit. The hybrid faucet can include a first mechanical valve with cylinder stem located upstream of an electronic valve to control a cold and hot water ratio and mix the hot and cold water to a desired water temperature. The hybrid faucet can include a second mechanical valve located downstream of the electronic valve for controlling water flow rate. 
         [0012]    In some embodiments, a hybrid faucet includes a faucet housing, one cartridge, an electronic control valve, two sensors (e.g., infrared sensors), a visual LED for indication, a logic processor, and/or a power supply unit. A cartridge can control cold and hot water ratio and water flow rate. 
         [0013]    In some embodiments, the hybrid faucet system includes a programmable logic processor with a circuit board that can control the sensors and electronic valves. In response to detection of an object within a primary sensor (Sensor C) detection zone (e.g., in a sink) for a predetermined period of time (e.g., a primary-sensor-on-time such as 2 seconds, 3 second, 4 second, 8 seconds, or some other time), the logic processor can activate the water flow electronic control valve (e.g., solenoid valve) for water flow to the faucet spout (e.g., activation of Intermittent-Water-Flow-Mode). 
         [0014]    In the Intermittent-Water-Flow-Mode, when the water flow electronic control valve (e.g., solenoid valve) is in an activated position for water flow and the primary sensor (e.g., Sensor C) senses no object in within the detection zone for a predetermined period of time (e.g., primary-sensor-off-time), the logic processor can deactivate the water flow electronic control electronic valve (e.g., solenoid valve) to stop water flow to the faucet spout (e.g., deactivation of Intermittent-Water-Flow-Mode). 
         [0015]    The secondary sensor (Sensor A) can be used to operate the hybrid faucet in continuous mode. In one embodiment, when sensor A detects a presence of an object (e.g., a hand) within the detection zone for a predetermined time period (e.g., Time Continue-flow-on time such as 2 seconds, 3 seconds, 5 seconds, 1.5 seconds, 8 seconds, or some other time), the logic processor activates the water flow electronic control valve (e.g., solenoid valve) for a continuous water flow (e.g., Continue-Water-Flow-Mode). This Continuous-Water-Flow-Mode operation is convenient for users when filling a sink or a container without keeping their hands within the detection zone of the primary sensor (Sensor C) for continuous water flow (e.g., activation of Continue-Water-Flow-Mode). 
         [0016]    The Continuous-Water-Flow-Mode can be deactivated when Sensor A senses the presence of an object (e.g., a hand) within the detection zone for a predetermined time period (e.g., a Continue-flow-off time). The logic processor can deactivate the water flow electronic control valve (e.g., solenoid valve) to stop the continuous water flow (e.g., deactivation of Continue-Water-Flow-Mode). 
         [0017]    In a stand-by mode (e.g., when the faucet is not operating), detection of an object (e.g.,, a hand or finger) within the detection zone of Sensor A for a predetermined time period (e.g., Time Sc-pause such as 4 seconds, 6 seconds, 3 seconds, 9 seconds, 5 seconds, or some other time) can trigger the logic processor to pause the function of the primary sensor (e.g., Sensor C). In this Faucet-Pause-Mode, a user can work within the primary sensor detection zone without activating faucet water flow for water conservation (e.g., beginning of Faucet-Pause-Mode). Accordingly, the logic processor can ignore intermittent signals from Sensor C during the pause mode. Pause mode can be reset via sensor A. When the secondary sensor (e.g., Sensor A) detects an object (e.g., a hand or finger) within the detection zone for a predetermined time period (e.g., Time Sc-reset such as 4 seconds, 3 seconds, 10 seconds, 2.5 seconds, 9 seconds, or some other time), the logic processor can reset the function of primary sensor (e.g., Sensor C). In some embodiments, the faucet system can set and reset pause mode by activating Sensor A and C simultaneously for a predetermined time period (e.g., 2 seconds, 3 seconds, 7 seconds, or some other time). 
         [0018]    In one or more embodiments, a logic processor circuit board comprises a hardware processor (e.g., microchip) and a circuit board. The logic processor can be programmed to function for input and output of all the electronic sensors (e.g., Sensor A, Sensor C), the visual LED for indication, and/or a water flow electronic control valve (e.g., solenoid valve). An electricity power supply package can include a battery pack (rechargeable or not) and/or an alternating current to direct current (AC-DC) transformer to supply direct current to the logic processor circuit board to activate the sensors and the flow electronic control valve. Some embodiments of the hybrid faucet system are less expensive and user friendly than full touch-free faucets systems. 
         [0019]    According to some variants, a faucet system includes a faucet body having a wall with an outer surface and an inner surface. The faucet system can include a first aperture in the wall of the faucet body, the first aperture having an aperture cross-section. In some embodiments, the faucet system includes a first sensor assembly. The first sensor assembly can be sized and shaped to be at least partially inserted into the first aperture through the outer surface of the wall of the faucet body. In some embodiment the first sensor assembly has a first sensor cover. The first sensor cover can have an open end and a closed end opposite the opened end. In some embodiments, the first sensor cover has a flange at least partially surrounding the closed end. In some embodiments, the flange has a flange cross-section larger than the aperture cross-section. In some cases, the first sensor assembly includes a first sensor circuit board connected to the first sensor cover. In some embodiments, the first sensor circuit board has a first surface facing the closed end of the first sensor cover and a second surface facing away from the closed end of the first sensor cover. The first sensor circuit board can include a sensor emitter on the first surface, a sensor receiver on the first surface, and a plug on the second surface. In some embodiments, the faucet system includes a first interconnect assembly. The first interconnect assembly can include a first interconnect box having an open end connected to the inner surface of the wall of the faucet body. In some cases, the first interconnect box has a closed end positioned within the faucet body spaced from the wall. In some embodiments, the open end of the first interconnect has a cross-section larger than the aperture cross-section. The first interconnect assembly can include a first interconnect circuit board connected to the first interconnect box. The first interconnect circuit board can be positioned at least partially within the first interconnect box. In some embodiments, the first interconnect circuit board has a socket configured to releasably connect with the plug of the first sensor circuit board. The first interconnect assembly can include an electronic connection point configured to connect with a connection cable. In some embodiments, connection between the plug and the socket electronically connects the first sensor circuit board to the connection cable. 
         [0020]    According to some variants, a hybrid faucet system includes a first infrared sensor. The first infrared sensor can be configured to communicate with processing electronics to initiate a first operating mode of a hybrid faucet responsive to detecting a first activation motion for a first time period. In some embodiments, the system includes a second infrared sensor. The second infrared sensor can be configured to communicate with processing electronics to initiate a second operating mode of the hybrid faucet responsive to detecting a second activation motion for a second time period. In some embodiments, the system includes a first manual controller. The first manual controller can be configured to change a first attribute of a water flow for a selected operating mode. In some embodiments, the system includes a second manual controller. The second manual controller can be configured to change a second attribute of a water flow for the selected operating mode. 
         [0021]    In some embodiments, the first operating mode comprises intermittent flow mode. In some cases, the system comprises a water inlet, a water outlet, and/or a control valve positioned in a water flow path between the water inlet and the water outlet. In some embodiments, when the system is operating in the intermittent flow mode, detection of an object in presence with the first infrared sensor for the first time period activates the control valve to permit water flow from the water inlet to the water outlet. In some cases, when no object is detected in the presence of the first infrared sensor deactivates the control valve to shut off water flow from the water inlet to the water outlet. In some embodiments, the second operating mode comprises continuous flow mode. 
         [0022]    In some embodiments, the system includes a water inlet, a water outlet, and/or a control valve positioned in a water flow path between the water inlet and the water outlet. In some cases, when the system is operating in the continuous flow mode, detection by the second infrared sensor of an object within a detection zone for a predetermined time period activates the control valve to permit water flow from the water inlet to the water outlet. In some embodiments, detection of an object within the detection zone by the second infrared for a second predetermined time period while the control valve is activated deactivates the control valve to shut off water flow from the water inlet to the water outlet. In some cases, the first attribute comprises temperature. In some cases, the second attribute comprises flow rate. In some embodiments, the second manual controller comprises an aerator flow rate valve. In some embodiments, said processing electronics is configured to: detect a first signal responsive to the first activation motion for the first time period; and/or detect a second signal responsive to the second activation motion for the second time period. In some cases, said processing electronics is configured to: detect time overlap between the first signal and the second signal; compare detected time overlap with a pause time period; and/or pause the first infrared sensor based on the said comparison. In some embodiments, said processing electronics is further configured to: compare the second time period with a pause time period. In some embodiments, the system includes a faucet body, wherein each of the first manual controller and the second manual controller are connected to and/or installed at least partially within the faucet body. In some embodiments, the system includes a faucet body, wherein one or more of the first manual controller and the second manual controller are connected to and/or installed at least partially within the faucet body. In some cases, each of the first infrared sensor and second infrared sensor are installed in the faucet body. In some cases, one or more of the first infrared sensor and second infrared sensor are installed in the faucet body. 
         [0023]    According to some variants, a sensor that is configured to provide touch-free control of an attribute of dispensed water can include an electronic circuit board of a first size that can pass through a receiving hole. The sensor can include a sensor cover of a second size that can pass through the receiving hole. In some cases, the sensor includes a securing module that can retain the sensor cover in a position with respect to the receiving hole. 
         [0024]    In some embodiments, the sensor includes a flange of a third size that is greater than the size of the receiving hole. In some cases, the sensor includes a faucet body. In some embodiments, the flange is mounted flush with the faucet body. In some cases, the first size of the electronic circuit board is smaller than the second size of the sensor cover. In some embodiments, the sensor includes an emitter configured to transmit radiation. The sensor can include a detector configured to receive reflected radiation. In some cases, at least one of the emitter or the detector is installed at a first plane that is a first distance away from the surface of the electronic circuit board. In some embodiments, the sensor includes electronic components. The electronic components can be installed under the first plane on the surface of the electronic board below the emitter or a detector. In some cases, the sensor includes legs that can elevate the emitter or the detector from the first plane, said legs including electrical connectivity. In some embodiments, the sensor includes a lens. 
         [0025]    According to some variants, a method of assembling a sensor for providing touch-free control of an attribute of dispensed water includes: inserting an electronic circuit board through a receiving hole; inserting a sensor cover through the receiving hole; and/or securing the sensor in position with respect to the receiving hole. In some cases, the method includes securing the sensor with a flange. In some embodiments, the method includes securing the sensor with securing modules. 
         [0026]    According to some variants, a method of installing a sensor for providing touch-free control of an attribute of dispensed water can include: providing a sensor suitable for insertion through a receiving hole from an exterior surface of a wall of an enclosed structure; providing an installation tool configured to slide inside the enclosed structure; providing a clip configured to secure the sensor with the enclosed structure; engaging a clip with the installation tool; inserting the sensor through the receiving hole; sliding the installation tool with the engaged clip inside the enclosed structure such that the clip aligns with one or more grooves of the sensor; disengaging the clip from the installation tool; and/or sliding out the installation tool from the enclosed structure. 
         [0027]    According to some variants, a method of repairing a sensor used in providing touch-free control of an attribute of dispensed water, said sensor installed from an exterior wall of an enclosed structure through a receiving hole, includes: sliding in an installation tool inside an enclosed structure; engaging the installation tool with a clip that secures the sensor with the enclosed structure; sliding out the installation tool with the engaged clip from the enclosed structure; and/or removing the sensor from the enclosed structure through a receiving hole. 
         [0028]    According to some variants, a hybrid faucet system can include a first infrared sensor. The first infrared sensor can be configured to communicate with processing electronics to initiate a first operating mode of a hybrid faucet responsive to detecting a first activation motion for a first time period. In some cases, the system includes a second infrared sensor. The second infrared sensor can be configured to communicate with processing electronics to initiate a second operating mode of the hybrid faucet responsive to detecting a second activation motion for a second time period. In some cases, the system includes a first manual controller. The first manual controller can be configured to change a first attribute of a water flow for a selected operating mode. In some cases, the system includes a second manual controller. The second manual controller can be configured to change a second attribute of a water flow for the selected operating mode. In some embodiments, one or more of the first infrared sensor and the second infrared sensor comprises: an electronic circuit board of a first size that can pass through a receiving hole; a sensor cover of a second size that can pass through the receiving hole; and/or a securing module that can retain the sensor cover in a position with respect to the receiving hole. In some embodiments, one or more of the emitter and the detector is a surface-mount device. 
         [0029]    According to some variants, a flow control valve configured to connect to a faucet system can include a valve body. The valve body can include an engagement portion configured to couple with a portion of the faucet system. In some embodiments, the valve body includes a cavity having an inner diameter. The valve can include a valve handle having an upstream end and a downstream end and configured to rotatably connect to the valve body. The valve handle can include a mating portion configured to be received at least partially within the cavity of the valve body. In some embodiments, the valve handle include a handle aperture through the upstream and downstream ends of the valve handle. The valve can include a top plate connected to one or both of the valve body and the valve handle. The top plate can have a plate aperture configured to align with the handle aperture to facilitate fluid communication between a source of fluid upstream of the flow control valve and an outlet of the flow control valve. 
         [0030]    In some embodiments, the valve includes an aerator configured to adjustably connect with the valve handle. In some cases, the plate aperture has a radial width with respect to a central axis of the valve handle. In some embodiments, the plate aperture has an arcuate length with respect to the central axis of the valve handle. In some cases, the radial width of the plate aperture varies along the arcuate length of the plate aperture. In some embodiments, the valve body includes an arcuate channel. In some embodiments, the valve handle includes a pin configured to fit at least partially within the arcuate channel of the valve body. In some cases, interference between the pin and walls of the arcuate channel limits a range of rotation between the valve handle and the valve body. In some embodiments, the valve includes a locking nut configured to fit at least partially within the cavity of the valve body and configured to mate with the mating portion of the valve handle. In some cases, the valve handle includes a valve shaft hole. The top plate can include a valve shaft aperture. In some embodiments, the flow control valve includes a valve shaft inserted at least partially through the valve shaft hole and the valve shaft aperture. In some cases, the valve shaft is configured to fixedly or releasably mate the valve handle to the top plate. In some embodiments, rotation of the valve handle about a central axis of the valve handle with respect to the top plate varies an area of overlap between the plate aperture and the handle aperture to vary a flow rate of water through the flow control valve. 
         [0031]    According to some variants, a faucet system includes a faucet body having a wall with an outer surface and an inner surface. The system can include a first aperture in the wall of the faucet body. The first aperture can have an aperture cross-section. In some embodiments, the system includes a first sensor assembly sized and shaped to be at least partially inserted into the first aperture through the outer surface of the wall of the faucet body. The first sensor assembly can include a first sensor cover having an open end, a closed end opposite the opened end, and/or a flange at least partially surrounding the closed end. In some embodiments, the flange has a flange cross-section larger than the aperture cross-section. In some cases, the first sensor assembly includes a first sensor circuit board connected to the first sensor cover. The first sensor circuit board can have a first surface facing the closed end of the first sensor cover, a second surface facing away from the closed end of the first sensor cover, a sensor emitter on the first surface, a sensor receiver on the first surface, and/or a plug on the second surface. In some embodiments, the system includes a first interconnect assembly. The first interconnect assembly can include a socket configured to releasably connect with the plug of the first sensor circuit board. In some cases, connection between the plug and the socket electronically connects the first sensor circuit board to a connection cable. 
         [0032]    In some embodiments, the first interconnect assembly includes a first interconnect box having an open end connected to the inner surface of the wall of the faucet body and a closed end positioned within the faucet body spaced from the wall. In some embodiments, the open end of the first interconnect having a cross-section larger than the aperture cross-section. In some embodiments, the first interconnect assembly includes a first interconnect circuit board connected to the first interconnect box and positioned at least partially within the first interconnect box. The first interconnect circuit board can include the socket. In some cases, the first interconnect assembly includes an electronic connection point configured to connect with the connection cable. 
         [0033]    In some embodiments, the sensor sleeve is positioned between the first sensor circuit board and the closed end of the first sensor cover. In some cases, the sensor sleeve includes a first aperture and a second aperture. In some embodiments, the sensor emitter is positioned at least partially within in the first aperture and the sensor receiver is positioned at least partially within the second aperture. 
         [0034]    According to some variants, a hybrid faucet system includes a first infrared sensor configured to communicate with processing electronics to initiate a first operating mode of a hybrid faucet responsive to detecting a first activation motion for a first time period. The system can include a first manual controller configured to control a flow rate of hot water into the hybrid faucet system. In some embodiments, the system includes a second manual controller configured to control a flow rate of cold water into the hybrid faucet system. The system can include a hot water check valve positioned upstream of the first manual controller and configured to inhibit or prevent passage of cold water in an upstream direction through the hot water check valve. In some embodiments, the system includes a cold water check valve positioned upstream of the second manual controller and configured to inhibit or prevent passage of hot water in an upstream direction through the cold water check valve. In some embodiments, the first manual controller comprises a hot water valve cylinder. The hot water valve cylinder can include a hollow cylindrical body having a first end, a second end, a sidewall extending between the first end and the second end, an inlet port in the sidewall, and an outlet port on the second end of the cylindrical body and in fluid communication with the inlet port. In some embodiments, the second manual controller comprises a cold water valve cylinder. The cold water valve cylinder can include a hollow cylindrical body having a first end, a second end, a sidewall extending between the first end and the second end, an inlet port in the sidewall, and an outlet port on the second end of the cylindrical body and in fluid communication with the inlet port. In some embodiments, the hot water valve cylinder is configured to rotated independently of the cold water cylinder. 
         [0035]    According to some variants, a valve system for a hybrid faucet system includes a step motor, a fluid outlet, a first fluid inlet, and/or a second fluid inlet. The system can include a first valve positioned downstream of the first fluid inlet and having an inlet and an outlet. In some embodiments, the first valve is configured to transition between an open configuration and a closed configuration. The system can include a second valve positioned downstream of the second fluid inlet and having an inlet and an outlet. In some embodiments, the second valve is configured to transition between an open configuration and a closed configuration. The system can include an intermediate fluid channel downstream of both the first and second valves and in fluid communication with one or both of the first and second valves. In some embodiments, the system includes a third valve positioned downstream of the intermediate fluid channel. The third valve can be configured to transition between an open position and a closed position in response to input from the step motor. In some embodiments the third valve is configured to prevent fluid passage between the intermediate fluid channel and the fluid outlet when in the closed position. In some embodiments, the third valve is configured to permit fluid passage between the intermediate fluid channel and the fluid outlet when in the opened position. 
         [0036]    In some embodiments, the valve system includes a valve system housing, and wherein each of the first, second, and third valves are positioned at least partially within the valve system housing. In some embodiments, the step motor is connected to a top end of the valve system housing. In some embodiments, the step motor is fluidly isolated from an interior of the valve system housing. In some embodiments, the third valve comprises a valve head and an actuator rod, the actuator rod connected to the step motor via a linear actuator. In some embodiments, the valve head is in contact with a valve seat when in the closed position and is spaced from the valve seat when in the open position. In some embodiments, a first check valve is positioned in a fluid flow path between the first fluid inlet and the first valve and a second check valve is positioned in a fluid flow path between the second fluid inlet and the second valve. In some embodiments, the first and second check valves are fluidly isolated from each other when one or more of the first valve and the second valve is in the closed configuration. In some embodiments, the first fluid inlet is a hot water fluid inlet and the second fluid inlet is a cold water fluid inlet. In some embodiments, the inlet of the first valve is perpendicular to the outlet of the first valve. In some embodiments, the inlet of the second valve is perpendicular to the outlet of the second valve. In some embodiments, one or both of the first valve and the second valve are configured to transition between the open and closed configurations in response to manual actuation of a lever, handle, or knob. In some embodiments, the step motor is configured to operate in response to input from an infrared sensor. In some embodiments, each of the first, second, and third valves are operated via input from sensors. 
         [0037]    According to some variants, a valve system for a hybrid faucet system can include a valve actuator, a fluid outlet, and/or a first fluid inlet. The system can include a first valve positioned downstream of the first fluid inlet and having an inlet and an outlet. The first valve can be configured to transition between an open configuration and a closed configuration in response to a first input. In some embodiments, the system includes a second valve positioned downstream of the first valve. The second valve can be configured to transition between an open configuration and a closed configuration in response to a second input from the valve actuator. In some embodiments, the second valve is configured to prevent fluid passage between the outlet of the first valve and the fluid outlet when in the closed position. In some embodiments, the second valve is configured to permit fluid passage between the outlet of the first valve and the fluid outlet. 
         [0038]    In some embodiments, the valve actuator is a step motor. In some embodiments, the first input is a manual input from a handle, knob, or lever. In some embodiments, the first input is input from an infrared sensor. In some embodiments, the second input is a manual input from a handle, knob, or lever. In some embodiments, the second input is input from an infrared sensor. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0039]    Embodiments disclosed herein are described below with reference to the drawings. Throughout the drawings, reference numbers are re-used to indicate correspondence between referenced elements. The drawings are provided to illustrate embodiments of the inventions described herein and not to limit the scope thereof. 
           [0040]      FIG. 1  illustrates an embodiment of a hybrid faucet system including a hybrid faucet that is configured to include touch and touch-free instrumentalities for controlling one or more attributes of flowing water from the hybrid faucet. 
           [0041]      FIG. 2  illustrates a cross section view of the hybrid faucet of  FIG. 1 . 
           [0042]      FIG. 3A  illustrates an embodiment of a water temperature cylinder stem. 
           [0043]      FIG. 3B  illustrates another orientation of the embodiment shown in  FIG. 3A   
           [0044]      FIG. 3C  illustrates an embodiment of a water flow cylinder stem. 
           [0045]      FIG. 4  illustrates an embodiment of a hybrid faucet with a temperature adjustment knob positioned opposite from the flow adjustment knob. 
           [0046]      FIG. 5  illustrates a cross section view of the hybrid faucet of  FIG. 4 . 
           [0047]      FIG. 6A  illustrates an embodiment of a water temperature control valve cylinder stem and a water flow control valve cylinder stem that can be used with the faucet of  FIG. 4 . 
           [0048]      FIG. 6B  illustrates water flow settings versus knob rotation angles according to an embodiment described herein. 
           [0049]      FIG. 7  illustrates an embodiment of a hybrid faucet with a sensor on the top cap of the hybrid faucet. 
           [0050]      FIG. 8  illustrates an embodiment of a hybrid faucet with a flow control valve configured to be positioned proximate the spout of the hybrid faucet; 
           [0051]      FIG. 9A  illustrates a front view of the water flow control valve shown in  FIG. 8 . 
           [0052]      FIG. 9B  illustrates a cross section view of the water flow control valve of  FIG. 8  along the cut plane A-A. 
           [0053]      FIG. 10  illustrates an exploded view of the water flow control valve of  FIG. 8 . 
           [0054]      FIG. 10A  illustrates a front view of another embodiment of a water flow control valve. 
           [0055]      FIG. 10B  illustrates a cross section view of the water flow control valve of  FIG. 10A  along the cut plane B-B. 
           [0056]      FIG. 10C  illustrates an exploded view of the water flow control valve of  FIG. 10A . 
           [0057]      FIGS. 11A and 11B  illustrate front and side views, respectively, of an embodiment of a sensor that can be installed from inside out through a receiving hole of a faucet. 
           [0058]      FIG. 12  illustrates an exploded view of an embodiment of a sensor that can be installed from inside out through a receiving hole of a faucet. 
           [0059]      FIG. 13  illustrates a bottom perspective view of an embodiment of an electronic circuit board. 
           [0060]      FIG. 14  illustrates an exploded view of an embodiment of a sensor that can be installed from outside in through a receiving hole of an assembly. 
           [0061]      FIGS. 15A-B  illustrate a side view of an embodiment of a sensor that was installed from outside in through a receiving hole of as assembly, for example, a faucet. 
           [0062]      FIG. 16  illustrates a top view of an embodiment of a sensor that was installed from outside in through a receiving hole of an assembly. 
           [0063]      FIG. 17  illustrates a bottom perspective view of an embodiment of an electronic circuit board that can be used in a sensor installed from outside in through a receiving hole of an assembly. 
           [0064]      FIG. 17A  illustrates an exploded view of an embodiment of a sensor that can be installed from outside in through a receiving hole of an assembly. 
           [0065]      FIG. 17B  illustrates a front perspective exploded view of an embodiment of a sensor that can be installed from outside in through a receiving hole of an assembly. 
           [0066]      FIG. 17C  illustrates a rear perspective exploded view of the sensor of  FIG. 17B . 
           [0067]      FIG. 17D  is a front view of the sensor of  FIG. 17B . 
           [0068]      FIG. 17E  is a cross section view of the sensor of  FIG. 17B  along the cut plane C-C of  FIG. 17D . 
           [0069]      FIG. 17F  is a cross section view of the sensor of  FIG. 17B  along the cut plane C-C of  FIG. 17D , including a sealant. 
           [0070]      FIG. 17G  is a schematic representation of an embodiment of a faucet assembly having a plurality of sensors and interconnecting circuit boards. 
           [0071]      FIG. 17H  illustrates a front perspective exploded view of an embodiment of a sensor that can be installed from outside in through a receiving hole of an assembly. 
           [0072]      FIG. 17I  illustrated a rear perspective exploded view of the sensor of  FIG. 17H . 
           [0073]      FIG. 18  illustrates a top view of an embodiment of a sensor that was installed from outside in through a receiving hole of an assembly and secured via securing modules. 
           [0074]      FIGS. 19A, 19B, and 19C  illustrate embodiments of securing modules. 
           [0075]      FIG. 20  illustrates an embodiment of a sensor, including an additional emitter, that can be installed from outside in through a receiving hole. 
           [0076]      FIG. 21  illustrates an embodiment of a process for installing a sensor from outside in via a receiving hole. 
           [0077]      FIG. 22A  illustrates an exploded view of a sensor that can be installed from outside in through a receiving hole. 
           [0078]      FIG. 22B  illustrated an embodiment of a securing module that can secure the sensor shown in  FIG. 22A . 
           [0079]      FIGS. 23A and 23B  illustrate a side view and a top view, respectively, of the sensor shown in  FIG. 22A  received by a receiving hole. 
           [0080]      FIG. 23C  illustrates an embodiment of a securing module that is a clip. 
           [0081]      FIG. 23D  illustrates a top view of another embodiment of a securing module that is a clip. 
           [0082]      FIG. 23E  illustrates a side view of the embodiment of the securing module of  FIG. 23D . 
           [0083]      FIG. 24  illustrates an embodiment of securing module coupled with the sensor of  FIG. 22A . 
           [0084]      FIG. 25A  illustrates an embodiment of a sensor engaged with the clip of  FIG. 23C . 
           [0085]      FIG. 25B  illustrates a top view of the embodiment shown in  FIG. 25A  received in a receiving hole and secured to the assembly. 
           [0086]      FIGS. 26A-B  illustrate an embodiment of an installation tool and a process for installing a securing module to a sensor with the installation tool. 
           [0087]      FIGS. 27A-B  illustrate another embodiment of an installation tool and a process for installing a securing module to a sensor with the installation tool. 
           [0088]      FIG. 28  illustrates an embodiment of a hybrid faucet system having a first valve configured to control flow rate of hot water and a second valve configured to control flow rate of cold water. 
           [0089]      FIG. 29  illustrates an embodiment of a hybrid faucet system having a hot water check valve and a cold water check valve. 
           [0090]      FIG. 30  illustrates a cross section view of the system of  FIG. 29 . 
           [0091]      FIG. 31  illustrates a perspective view hot and cold water valve cylinders of the systems of  FIGS. 28 and 29 . 
           [0092]      FIG. 32  illustrates a side view of a valve system of the hybrid faucet system of  FIG. 29 . 
           [0093]      FIG. 33  illustrates a cross section view of the valve system of  FIG. 32 , taken along the cut plane A-A of  FIG. 32 . 
           [0094]      FIG. 34  illustrates a hybrid faucet system having a first valve configured to control flow rate of hot water, a second valve configure to control flow rate of cold water, and a second sensor. 
           [0095]      FIG. 35  illustrates a hybrid faucet system having a hot water check valve and a cold water check valve. 
           [0096]      FIG. 36  illustrates a right front perspective view of a hybrid faucet system having a second sensor on top of the faucet body. 
           [0097]      FIG. 37  illustrates a left front perspective view of the hybrid faucet system of  FIG. 36 . 
           [0098]      FIG. 38  illustrates a perspective view of an embodiment of a step motor. 
           [0099]      FIG. 39  illustrates a rear cross section view of a valve system for a hybrid faucet system. 
           [0100]      FIG. 40  is a bottom cross section view of the valve system of  FIG. 39 , taken along the cut-plane  40 - 40  of  FIG. 39 . 
           [0101]      FIG. 41  is a side cross section view of the valve system of  FIG. 39 , taken along the cut-plane  41 - 41  of  FIG. 39 . 
           [0102]      FIG. 42  is an exploded view of a portion of the valve system of  FIG. 39 . 
           [0103]      FIG. 43  illustrates a perspective view of an embodiment of a step motor. 
           [0104]      FIG. 44  illustrates a rear cross section view of a valve system for a hybrid faucet system. 
           [0105]      FIG. 45  is a bottom cross section view of the valve system of  FIG. 44 , taken along the cut-plane  45 - 45  of  FIG. 44 . 
           [0106]      FIG. 46  is a side cross section view of the valve system of  FIG. 44 , taken along the cut-plane  46 - 46  of  FIG. 44 . 
       
    
    
     DETAILED DESCRIPTION 
       [0107]    Although certain embodiments and examples are disclosed herein, inventive subject matter extends beyond the examples in the specifically disclosed embodiments to other alternative embodiments and/or uses, and to modifications and equivalents thereof. Thus, the scope of the disclosure is not limited by any of the particular embodiments described herein. For example, in any method or process disclosed herein, the acts or operations of the method or process may be performed in any suitable sequence and are not necessarily limited to any particular disclosed sequence. Various operations may be described as multiple discrete operations in turn, in a manner that may be helpful in understanding certain embodiments; however, the order of description should not be construed to imply that these operations are order dependent. Additionally, the structures, systems, and/or devices described herein may be embodied as integrated components or as separate components. For purposes of comparing various embodiments, certain aspects and advantages of these embodiments are described. Not necessarily all such aspects or advantages are achieved by any particular embodiment. Thus, for example, various embodiments may be carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other aspects or advantages as may also be taught or suggested herein. 
         [0108]    The drawing showing certain embodiments can be semi-diagrammatic and not to scale and, particularly, some of the dimensions are for the clarity of presentation and are shown greatly exaggerated in the drawings. 
         [0109]    Touch-free assemblies, for example faucets, include a sensor for detecting objects and motions to control one or more operations associated with said assembly. The sensor generally includes an emitter for transmitting radiation and a detector for receiving the reflected radiation. The emitter and detector can be attached to an electronic circuit board, e.g. a printed circuit board (PCB). The circuit board may include electronic circuit elements for driving the emitter and receiving signals from the detector. Touch-free faucets can provide a more hygienic means of washing hands and performing other tasks associated with traditional faucets. However, many touch-free faucets in the industry lack controls to modify attributes (flow rate, temperature, etc.) or mode (pause mode, continuous mode, etc.) of water flow through the touch-free faucet. Accordingly, there remains a need to enhance operation of a touch-free faucet. In some cases, touch-free faucets can be more convenient than traditional faucets. However, they can also be more expensive. Moreover, touch-free faucets can be difficult to repair, especially if there is any problem with the sensor. Typically in a touch free faucet, the sensors are mounted inside out through the interior of a faucet. This can make installation and repairs time consuming and expensive. Accordingly, there remains a need to enhance sensor assembly in a touch-free faucet. 
         [0110]    Certain embodiments described herein disclose a hybrid lavatory-bathroom-kitchen-type faucet systems that include both touch and touch free functionalities. In order to provide water-efficient operation that might be easy and convenient to use, the water flow can be activated and deactivated in response to a primary electronic sensor (Sensor C) that detects presence of an object so as to provide the water-efficient operation in intermittent-water-flow-mode. For other applications, such as filling the sink or bathtub, a container or for washing dishes, washing food, running a shower, etc., the hybrid faucet system can include a continuous water flow mode. The continuous water flow mode can be activated using a secondary electronic sensor (Sensor A). In one embodiment, the hybrid faucet system can be switched between a continuous-water-flow-mode and intermittent-water-flow-mode without touching any part(s) of the faucet body. Accordingly, the personal hygiene of a person can be protected by not having to come into contact with any portion of the faucet. 
         [0111]    The hybrid faucet system can also include a Pause-Mode that can enable a user to work in the vicinity of the faucet without worrying about accidentally activating the sensors. Furthermore, the hybrid faucet system can also include mechanical control valves (e.g., manual valves configured to be mechanically operated by the user) to adjust and maintain water flow and temperature settings for user convenience and water conservation. 
         [0112]      FIG. 1  illustrates an embodiment of a hybrid faucet system including a temperature and a flow control valve assembly. The hybrid faucet system  100  can include a faucet body  102 , an electronic primary water flow sensor (e.g. infrared sensor IR  112 ), an electronic continuous water flow sensor (e.g. infrared sensor IR  114 ), a first manual valve (e.g., water temperature adjustment knob  108 ), a second manual valve (e.g., water flow adjustment knob  110 ), and a faucet valve control assembly  116 . One or more of the manual valves (e.g., valves configured to operate in response to manual user input such as, for example, turning a knob, pressing a button, rotating a handle, etc.) can be installed on and/or in the faucet body  102 . One or more of the sensors (e.g., IR sensors  112 ,  114 ) can be installed/replaced from outside of the water faucet body  102 , as will be discussed in detail below with respect to sensors  2100 ,  2400 ,  2800 ,  3200 ,  3800 ,  3900 ,  4002 ,  4100 . The faucet valve control assembly  116  can include a mechanical valve  118  to control water flow ratio of cold water inlet  128  and hot water inlet  130  and mixed to a user&#39;s desired water temperature, a mechanical valve  120  to control water flow rate of the mixed water, an electronic control valve such as solenoid valve  122 , a logic processor  124 , a power supply package  126 , and/or any combination or sub-combination of the above components. For example, the faucet valve control system  116  may not include a solenoid valve  122 . In an embodiment, the logic processor is a hardware processor (e.g. microchip). The logic processor  124  can be configured to detect a signal input  140  from electronic primary flow sensor  112  and/or input signal  142  from the electronic continuous flow sensor  114 . Based on the detected input signals, the logic processor  124  can output a signal  144  to electronic control valve (solenoid valve  122 ) to tog on/off the mixed cold/hot water flow ( 134 ,  136 ) to faucet spout  102  and aerator  106 . The electronic continuous water flow sensor  114  can be located on either side of the faucet body  102  or on the top of faucet body  102 . As illustrated, the primary water flow sensor  112  may be located to facing to the spout aerator direction to sense object or hands in the electronic sensing area of sink to turn on and off water flow. The power supply package  126  can include one or more batteries, one or more rechargeable batteries, a solar cell system, or a DC voltage supplied from an AC/DC converter. The power supply package  126  can deliver DC power  146  to the logic processor. The faucet valve control assembly  116  can be housed in the faucet body  102  or enclosed in a separate control box. 
         [0113]      FIG. 2  is illustrates a cross-sectional view of a portion of the hybrid faucet system of  FIG. 1 . The illustrated embodiment includes a faucet body  102 , two electronic sensors (usually infrared sensor IR  112  and  114 ), a water inlet assembly  218 , a mechanical water temperature control assembly  224 , a mechanical water flow control assembly  228 , an electronic flow control valve  234  with electronic actuator  236 , a spout  104 , an aerator  106 , a control assembly  116 , a power supply assembly, and/or any combination or sub-combination of the above components. For example, the faucet system  100  may not include an electronic flow control valve  234  with an electronic actuator. In the illustrated embodiment, the water inlet assembly  218  includes two inlet holes with a chamber to embed a check valve  220  on each inlet stream to prevent cross flow between the cold and hot water supply line. The check valve  220  with a strainer can also be installed on the inlet hose connector or between the cold/hot water supply valve and the water inlet hose to remove foreign particles in the inlet water. The cold and hot water can flow from the inlet pipes  216  through the check valve  220  and exit through water channels to a mechanical temperature control valve  224  which can include a temperature cylinder stem  300  with control holes to adjust inlet of cold and hot water flow ratio for desired water temperature. 
         [0114]      FIG. 3A  illustrates an embodiment of a water temperature cylinder stem  300 . As illustrated, the control stem  300  can include a temperature stem body  301 . In some cases, the temperature stem body  300  has a generally cylindrical shape. Cold water can flow from the inlet channel through the control gap between the cold water inlet hole  308  and cylinder housing wall into the inner channel. Hot water can flow from the inlet channel through the control gap between the hot water inlet hole  312  and cylinder housing wall into the inner channel. The mixed water can exit from the outlet hole  310  and go into the flow control valve inlet channel  226  and then to the water flow control valve  228 . The cylinder stem can also include a groove  302  on the top to fasten a temperature knob  108  of  FIG. 1 . An angle cut stop groove  304  (shown in  FIG. 3B ) can set the cylinder rotation angle and may prevent the cylinder stem from popping out of the mechanical control valve body  224 . In some embodiments, setting the cylinder rotation angle can inhibit or prevent accidental contact or impact between the temperature knob  108  and other structures of the faucet system  100  (e.g., the flow adjustment knob  110 ). An O-ring groove  306  with O-ring can stop water leaking from the housing of water temperature control valve  224 . The hot water inlet hole  312  may be of a different size and shape than the cold water inlet hole  308  to control temperature of the mixed water for safety purposes. The hot water inlet hole  312  may also be offset from the cold water inlet hole  308  to control maximum and minimum temperature of the mixed water. As illustrated in  FIG. 3A , in some embodiments, the cold water inlet hole  308  and hot water inlet hole  312  at least partially overlap each other in a direction measured along the circumference of the temperature stem body  301 . In some embodiments, the cold water inlet hole  308  and hot water inlet hold  312  at least partially overlap each other in a direction substantially parallel to the longitudinal axis of the temperature stem body  301 .  FIG. 3B  illustrates another orientation of the embodiment shown in  FIG. 3A . 
         [0115]      FIG. 3C  illustrates an embodiment a flow control cylinder stem  350 . In an embodiment, the flow control cylinder stem  350  is arranged in a manner such that it receives mixed water from the outlet  310  of the water temperature cylinder stem  300 . The mixed water can flow from the mixed water outlet channel  226  through the control gap between the inlet hole  358  and cylinder housing wall into the inner water channel  360  and exit from the outlet hole  362  to the electronic control valve  234  inlet channel  232 . The flow control cylinder stem  350  can also include a groove  352  on the top to fasten a flow adjustment knob  110  of  FIG. 1 . A stop groove  354  can limit the cylinder rotation angle to keep the cylinder stem from popping out from the mechanical control valve body  228 . In some embodiments, limiting the cylinder rotation angle of the flow control cylinder stem  350  can reduce the likelihood that the flow adjustment knob  110  is impacted upon the temperature knob  108  during use. An O-ring groove  356  with O-ring can stop water leaking from the housing of water flow control valve  228 . Accordingly, the orientation (which can be controlled by the respective knobs  108  and  110 ) of the mixed water outlet hole  310  relative to the flow inlet hole  358  can control the flow rate of the mixed water. 
         [0116]    The adjusted water flow from the flow control cylinder  350  can then pass through the electronic control valve such as a solenoid valve  234  with an actuator  236  that can control on/off flow to the faucet spout channel ( 238  and  240 ). In some embodiments, the solenoid valve  234  and actuator  236  can be configured to meter flow through the faucet spout channels  238 ,  240  to control flow rate through the faucet. The water can then flow through the aerator  206 . Accordingly, the cold/hot water flow can be controlled by the mechanical water temperature control valve assembly  224 , mechanical water flow control valve assembly  228  and electronic water flow control valve  234  to a desired water temperature and flow rate. 
         [0117]    Although the hybrid faucet system  100  has been described as including an electronic valve, one of ordinary skill in the art will appreciate that the faucet  100  could include more than one electronic valve and/or the faucet could include one or more mechanical valves in series or in parallel with the electronic valve(s). 
         [0118]      FIG. 4  illustrates an embodiment of a hybrid faucet system including a temperature and flow control valve assembly. The hybrid faucet system  400  includes a faucet body  102 , an electronic primary water flow sensor (usually infrared sensor IR  112 ), an electronic continuous water flow sensor (usually infrared sensor IR  114 ), a water temperature adjustment knob  108 , a water flow adjustment knob  110  and a faucet water control valve assembly  116 . The faucet control valve assembly  116  can include a mechanical water temperature control valve  118  to control water flow ratio of cold water inlet  128  and hot water inlet  130  to be mixed to a user&#39;s desired water temperature, a mechanical valve  120  to control water flow rate of the mixed water  132 , an electronic control valve such as solenoid valve  122 , a logic processor  104 , and a power supply package  126 , and/or any combination or sub-combination of the above components. For example, the faucet system  400  may not include the electronic control valve  122 . The logic processor  104  is configured to receive an input signal  140  from an electronic primary water flow sensor  112  to start an intermittent water flow and an input signal  142  from electronic continuous water sensor  454  to start a continuous water flow. The logic processor  104  can output a signal  144  to an electronic water flow control valve (solenoid valve  122 ) to turn on and off the mixed water flow  134 . The mixed water  136  can then flow to faucet spout  104  and the aerator  106 . The electronic continuous water flow sensor  114  can be located on either side of the faucet body  102  or on the top of faucet body  102 . The primary water flow sensor  112  can face in the spout aerator direction to sense object or hands in the electronic sensing area of sink to control water flow. In one embodiment, the power supply package  126  may include one or more a batteries, one or more rechargeable batteries, a solar cell system, a DC voltage supplied from an AC/DC converter, etc. to supply DC power  464  to the logic processor. The faucet valve control assembly  116  can be housed in the faucet body  102  or enclosed in a separate control box. Compared to the embodiment illustrated in  FIG. 1 , the temperature and control knobs are located on opposite sides of the hybrid faucet system  400 . 
         [0119]      FIG. 5  illustrates a cross section view of a portion of the faucet system  400  of  FIG. 4 . As discussed above, the hybrid faucet system  400  includes a faucet body  102 , two electronic sensors (usually infrared sensor IR  112  and  114 ), a mechanical water temperature and flow control assembly  518 , an electronic flow control valve  528  with electronic actuator  530 , a spout  104 , an aerator  106 , a control assembly  116 , a power supply assembly, and/or any combination or sub-combination of the above components. For example, the faucet system  400  may not include an electronic flow control valve  528 . In the illustrated embodiment, the mechanical water temperature and flow control assembly  518  includes two inlet holes  522  with a chamber to embed a check valve  520  on each water supply inlet to prevent cross flow between the cold and hot water supply line. The check valves  520  with strainer can also be installed on the inlet hose connector or between the cold/hot water supply valve and the water inlet hose to remove foreign particles in the inlet water. In an embodiment, the cold and hot water flow from the inlet pipes  516  through the check valve  520  and water inlet channel  522  to a mechanical water temperature and flow control valve cylinder assembly  600 . 
         [0120]      FIG. 6A  illustrates an embodiment of a mechanical water temperature and flow control valve cylinder assembly  600  which includes a water temperature control valve cylinder stem  602  and a water flow control valve cylinder stem  652 . The cold water can flow from the cold water inlet channel (one of  522 ) through a gap between the inlet cut hole  610  and the cylinder housing wall of water temperature and flow control valve body  518  into the inner channel  614  of the water temperature control valve cylinder stem  602 . The hot water can flow from the hot water inlet channel (another one of  522 ) through a gap between the inlet cut hole  612  and the cylinder housing wall of water temperature and flow control valve body  518  into the inner channel  614  of the water temperature control valve cylinder stem  602 . As illustrated, the inlet cut holes  610 ,  612  can at least partially overlap each other in a direction along the circumference of the cylinder stem  652 . In some embodiments, the inlet cut holes  610 ,  612  at least partially overlap each other in a direction perpendicular to the central axis of the cylinder stem  652 . The water temperature control cylinder stem  602  can include a groove  604  on the top to fasten a water temperature adjustment knob  108  of  FIG. 4 . A stop groove  606  can limit the cylinder rotation angle and keep the cylinder stem from popping out of the mechanical control valve body  518 . An O-ring groove  608  with O-ring can stop water leaking from the housing of water temperature control valve  518 . The rotation of the water temperature control valve cylinder stem  602  can change the size of the gap between the cold water inlet cut hole  610 , hot water inlet cut hole  612 , and the water temperature and flow control valve body  518  wall to adjust the ratio of inlet cold and hot water. Accordingly, the temperature of the mixed water can be controlled. 
         [0121]    The mixed water  616  can flow from the inner channel  614  of the water temperature control valve cylinder stem  602  through a washer  622  into a water flow control valve cylinder stem  652 . The mixed water can exit through a gap between a flow control cut hole  660  and the water temperature and flow control valve  518  wall to the water channel  524 . The water flow control cylinder stem  652  also includes a groove  654  on the top to fasten a water flow adjustment knob  110  of  FIG. 4 . A stop groove  656  can limit the cylinder rotation angle and keep the cylinder stem from popping out of the mechanical control valve body  518 . An O-ring groove  658  including an O-ring can stop water leaking from the housing of water temperature control valve  518 . The rotation of the water flow control valve cylinder stem  652  can change the size of the gap between the water flow control cut hole  660  and the water temperature and flow control valve body  518  wall to adjust the water flow according to the user&#39;s desired water flow.  FIG. 6B  illustrates water flow settings versus knob rotation angles according to an embodiment described herein. 
         [0122]    In an embodiment, the regulated water flows through the mechanical control valve outlet channel  524  and the electronic control valve inlet channel  526 . Accordingly, the water passes through the electronic control valve such that a solenoid valve  528  with an actuator  530  can control on/off flow to the faucet spout channel ( 532  and  534 ). The water can exit from through the aerator  106 . Thus, the cold/hot water flow can be controlled by the water temperature and flow control valve assembly  518  and electronic water flow control valve  528  to the user&#39;s desired water temperature and flow rate. 
         [0123]    Although the faucet  500  has been described as including an electronic valve, one of ordinary skill in the art will appreciate that the faucet  500  could include more than one electronic valve and/or the faucet could include one or more mechanical valves in series or in parallel with the electronic valve(s). 
         [0124]      FIG. 7  illustrates an embodiment of a hybrid faucet  700  where one of the sensors is placed on top of the faucet body  102 . The hybrid faucet  700  includes a spout  104 , a water aerator  106 , a water temperature adjustment knob  108 , a water flow adjustment knob  110 , an electronic primary water flow sensor (usually infrared sensor IR  112 ) activates an intermittent water flow when the sensor  112  senses an object in the sensing area of sensor  112 . Another sensor  722  can be located on either side of faucet body  102  of  FIG. 4  or on the top cap  708  of faucet body  102  senses an object in the sensing area and can generate a signal to activate a continuous water flow for continuous water usage or filling a container. 
         [0125]      FIG. 8  illustrates an embodiment of a hybrid faucet  800  with an aerator control. The faucet system  800  includes a faucet body  102 , an electronic primary water flow sensor (usually infrared sensor IR  112 ), an electronic continuous water flow sensor (usually infrared sensor IR  114 ), a water temperature adjustment knob  108 , a faucet water control valve assembly  116 , and a mechanical water flow control valve  808 . In some embodiments, the control valve  808  controls water and the knob  108  controls flow. The faucet water control valve assembly  116  includes a mechanical water temperature control valve  118  to control water flow ratio of cold water inlet  128  and hot water inlet  130  to be mixed to user&#39;s desired water temperature, an electronic control valve such as solenoid valve  122 , a logic processor  124 , a power supply package  126 , and/or any combination or sub-combination of the above components. For example, the faucet  800  may not include an electronic control valve  122 . The logic processor  124  receives an input signal  140  from an electronic primary water flow sensor  112  to start an intermittent water flow and an input signal  142  from electronic continuous water sensor  114  to start a continuous water flow and outputs a signal  860  to an electronic water flow control valve (solenoid valve  122 ) to tog on/off the mixed water flow  132  to faucet spout  804 . The mixed water flow  826  from the electronic control valve  122  can flow through a mechanical water flow control valve  808  and an aerator  810 . The electronic continuous flow sensor  114  can be located on either side of the faucet body  102  or on the top of faucet body  102 . The primary water flow sensor  112  can face the spout aerator direction to sense objects or hands in the electronic sensing area of sink to tog on/off water flow. In one embodiment of the invention, the flow control valve can maintain a minimum opening to keep a minimum water flow such the user can know the status of the electronic water flow control valve (solenoid valve). 
         [0126]      FIG. 9A  illustrates an embodiment of the water flow control valve  808  of  FIG. 8 . The water flow control valve  808  can includes a valve body  902  with thread  908  to thread into the spout, a valve handle  904  with knob  906  to adjust water flow. An aerator  810  can also be included in the valve handle  904 . The valve  808  can include one or more cuts  916  on the valve body  902  to fasten the valve body  902  on to the spout. The valve  808  can also include a valve shaft  910  and a retaining clip  912 . 
         [0127]      FIG. 9B  illustrates a cross section view of the water flow control valve  808 . As discussed above, the water flow control valve  808  includes a valve body  902  with thread  908  to be fastened into spout. A water flow control disk  956  with openings  972  to adjust water flow may be attached on the valve body  902 . In some embodiments, as illustrated, the flow control disk  956  includes two openings  972 . The disk  956  can include 1, 3, 4, 5, 6, 7, or some other number of openings  972  according to the application needs. A valve handle  904  with knobs  906  can be fastened to the valve body  902  with a valve shaft  910  and a retaining clip  912 . The valve handle  904  can include 1, 3, 4, 5, 6, or some other number of knobs  906  to provide tactile engagement for turning the handle  904 . As illustrated, in some embodiments, the handle  904  includes 2 knobs  906 . 
         [0128]    Water flow may be adjusted as it flows through the gap between the opening  972  of the water flow control disk  956  and the opening  974  of the valve handle  904 . For example, the openings  972  can have a generally arcuate shape with varying radial width (e.g., with respect to a rotational axis of the handle  904 ) along the arcuate lengths of the openings  972 . Rotation of the valve handle  904  can change the positions of the openings  974  along the arcuate lengths of the openings  972 . Changing the relative positions between the openings  974  and the openings  972  can change the size of the gaps between the openings  972 ,  974  to change the water flow rate through the control valve  808 . Adjusting the water flow rate through the valve  808  can permit the user to conserve water, to customize the flow shape out of the aerator  810 , and/or to otherwise customize the water flow through the flow control valve  808 . An O-ring  966  between the valve body  904  and valve handle  962  can inhibit or prevent water from leaking. A valve rotation angle set pin  968  can control the rotation angle of the valve handle  904  and valve body  902  (e.g., to prevent complete closure of the gap between the openings  972 ,  974 ). 
         [0129]      FIG. 10  illustrates an exploded view of the embodiment of water flow control valve  808 . The illustrated embodiment shows a water flow control disk  956  with openings  974  to adjust water flow attached on the valve body  902 . A valve handle  904  with knobs  906  is fastened to the valve body  902  with a valve shaft  910  and retaining clip  912  sized and shaped to fit into a clip channel  992  of the valve shaft  910 . Water flow can be adjusted through the gap between the opening  972  of the water flow control disk  956  and the opening  974  of the valve handle  904 . A valve shaft hole  918  on the valve handle  904  can be included for the valve shaft  910  to fasten the valve handle  904  to the valve body  902 . Cuts  976  on the valve body  902  may assist in installation of the flow control valve  808  on the spout. An O-ring  966  and the O-ring groove  986  on the valve handle  904  may seal the water leaking between the valve body  902  and valve handle  904 . The valve rotation angle set pin  968  can control the rotation angle of the valve handle  904  and valve body  902 . An aerator  810  is attached on the valve handle  904 . 
         [0130]      FIGS. 10A-10C  illustrate an embodiment of a flow control valve  1000 . The flow control valve  1000  shares some features and advantages with the flow control valve  900  (e.g., the use of an aerator  1010  and a valve handle  1004 , water flow and shape adjustment, water conservation, etc.). The flow control valve  1000  can include valve body  1002 . The valve body  1002  can be configured to connect to the spout of a sink (e.g., spout  804  of  FIG. 8 ) via threaded engagement of threads  1005  and/or via some other connection method or mechanism (e.g., adhesives, welding, frictional engagement, fasteners, etc.). 
         [0131]    The valve body  1002  can include a cavity  1054  in which one or more valve components may be housed. For example, a locking nut  1008  can be housed within the cavity  1054 . The nut  1008  can have an outer diameter that is less than or equal to an inner diameter of the cavity  1054 . The nut  1008  can include threading  1052  on an interior diameter of the nut  1008 . In some embodiments, the valve  1000  includes a washer  1012  positioned between the nut  1008  and the valve body  1002 . 
         [0132]    The flow control valve  1000  can include a valve handle  1004 . The valve handle  1004  can include a mating portion  1088 . The mating portion  1088  can be configured to facilitate connection between the valve handle  1004  and the valve body  1002 . For example, in some embodiments, the mating portion  1088  includes a threaded portion  1064  configured to threadedly engage with the threading  1052  of the locking nut  1008  within the cavity  1054  of the valve body  1002 . Engagement between the mating portion  1088  and the lock nut  1008  can inhibit or prevent accidental removal of the valve handle  1004  from the valve body  1002 . In some embodiments, the lock nut  1008  and/or valve handle  1004  are configured to rotate freely with respect to the valve body  1002  without disengagement between the lock nut  1008  and the valve handle  1004 . Engagement and/or interference between a widened portion  1094  of the valve handle  1004  and a shoulder  1096  of the valve body  1002  can limit movement of the mating portion  1088  into the cavity  1054  of the valve body  1002 . In some embodiments, the valve handle  1004  includes an O-ring channel  1086  in which an O-ring can be positioned to inhibit leakage of water or other fluids between the valve body  1002  and the valve handle  1004 . 
         [0133]    In some embodiments, the flow control valve  1000  includes a top plate  1056 . The top plate  1056  can include one or more apertures  1072  through the plate  1056 . For example, the plate  1056  can include a single aperture  1072 , as illustrated. In some embodiments, the plate  1056  includes 2, 3, 4, or more apertures  1072 . The apertures  1072  can have a varying radial width (e.g., with respect to an axial centerline of the valve  1000 ) along an arc length of the apertures  1072 . In some embodiments, the top plate  1056  includes one or more tabs  1044 . The tabs  1044  can be configured to facilitate fixed or releasable engagement between the top plate  1056  and the valve body  1002 . For example, the tab  1044  can be configured to deflect when transitioned into engagement with a tab slot  1046  of the valve body  1002  (e.g., a tab slot  1046  on the inner diameter of the cavity  1054  of the valve body  1002 ). The tab  1044  can return to an undeflected or less deflected state upon mating of a portion of the tab  1044  (e.g., a tooth on the end of the tab  1044 ) with a portion of the valve body  1002 . In some embodiments, engagement between the tab  1044  and the tab slot  1046  can inhibit or prevent rotation of the top plate  1056  with respect to the valve body  1002 . 
         [0134]    The valve handle  1004  can include a handle aperture  1074  through the valve handle  1004 . Upon assembly of the control valve  1000 , the handle aperture  1074  can be at least partially aligned with the aperture  1072  of the plate  1056  to facilitate fluid communication between a water source upstream of the plate  1056  and an aerator  1010  or other outlet structure (e.g., an opening) of the flow control valve  1000 . The aerator  1010  can be a conventional faucet aerator. For example, the aerator  1010  can have multi-hole nozzle (not shown) extending through a thickness of the aerator  1010  to add air to water passing through the aerator  1010 . Rotation of the valve handle  1004  with respect to the valve body  1002  and top plate  1056  can increase or decrease the size of the overlap between the aperture  1072  of the top plate  1056  and the handle aperture  1074 . Changing the overlap size between the aperture  1072 ,  1074  can increase or decrease the flow rate of water through the flow control valve  1000 . In some embodiments, the valve handle  1004  includes one or more tactile features (e.g., knobs  1006 ) to facilitate rotation of the valve handle  1004  with respect to the valve body  1002 . 
         [0135]    The handle  1004  and/or the valve body  1002  can include rotation-limiting structures. For example, the valve handle  1004  can include a pin  1068  or other protrusion configured to fit within an arcuate channel  1032  of the valve body  1002 . Interference between the pin  1068  and channel  1032  can limit rotation of the valve handle  1004  with respect to the valve body  1002  (e.g., a 30 degree arc length of the channel  1032  could limit rotation of the valve handle  1004  to a 30 degree range). Limiting the range of rotation between the valve handle  1004  and the valve body  1002  can reduce the likelihood of inadvertent shut-off of the control valve  1000  via complete misalignment of the apertures  1072 ,  1074 . In some embodiments, the valve  1000  includes a washer  1047  between the top plate  1056 /valve body  1002  and the spout to which the valve  1000  is mated. 
         [0136]      FIGS. 11 and 12  illustrate a sensor from the prior art that is installed inside out and through the interior of a faucet. As discussed above, such a sensor can be used instead of or in addition to the sensors described above with respect to  FIGS. 1-10 .  FIG. 11A  illustrates a front view of a sensor  2100  including a lens  2102  assembled within a receiving hole  2104  of the faucet  2106 .  FIG. 11B  illustrates a side view of the sensor  2100  mounted to the faucet  2106 . The sensor  2100  can include a sensor cover  2108  and a lens  2102 . Wires  2112  can connect the electronic components of the sensor to a logic processor (not shown). The logic processor can receive and analyze input signals and accordingly control an operation of the faucet. In the illustrated embodiment, the size of the sensor cover  2108  is greater than the size of the receiving hole  2104 . Accordingly, the sensor  2100  was mounted through the interior of the faucet. The sensor is secured internally with the inner wall  2110  via a screw  2114 . 
         [0137]      FIG. 12  illustrates an exploded view of the sensor  2100  described above with respect to  FIG. 11 . The sensor can include a sleeve  2202  to reduce noise by separating the emitter  2204  from the detector  2206  with a partition. Typically, the base of the emitter  2204  and the detector  2206  lie adjacent to the surface of the electronic circuit board  2210 . As shown, the electronic circuit elements (or electronic components)  2212  can be mounted on the electronic circuit board  2210  alongside the emitter  2204  and the detector  2206 . The electronic components  2212  can include, for example, capacitors, resistors, transistors, inductors, integrated circuits (IC) and the like. The wire connectors  2208  can enable physical and electrical connection of wires between the electronic circuit board  2206  and the logic processor. Wires can be soldered on to the electronic circuit board  2210  at the wire connectors  2208  or clipped on to the electronic circuit board  2210 . The electronic components  2212  might be placed on both sides of the electronic circuit board  2210 . The electronic components  2212  can also be soldered on to the electronic circuit board  2206 . Valuable space on the surface of the board is occupied by the emitter  2204  and the detector  2206  such that the board must be sized larger than the emitter and detector to accommodate the necessary electronic components. 
         [0138]      FIG. 13  illustrates a perspective bottom view of an embodiment of an electronic circuit board  2210  where the electronic components are mounted on both the top and bottom surfaces. The electronic circuit board  2210  can include emitter installation holes  2302 , detector installation holes  2304 , and wire connectors or wires  2112  to enable power supply and signal communication. 
         [0139]    As described above, inserting the sensor inside out from the interior of an assembly, such as a faucet, can be challenging and time consuming. Thus, it may be beneficial to assemble the sensor from outside in through a receiving hole of a faucet. There are, however, other constraints for installing the sensor outside in through the receiving hole of a faucet. The receiving hole may have size restrictions, for example, due to aesthetics, lack of space, or performance reliability. Performance may be compromised by increasing the size of the receiving hole. For instance, if the sensor area is too large, the user may not be able to identify the optimal detection area. Due to the size restrictions on the receiving hole, the sensor size including the size of the electronic circuit board may need to be reduced to fit through the receiving hole. However, reducing the dimensions of the electronic circuit board can result in not enough surface area for mounting electronic components. Miniaturization of the electronic components may also not be feasible due to performance and cost restrictions. Thus, inserting a sensor from outside in through a wall of the faucet may require balancing the size restriction of the receiving hole with the necessary surface area needed for mounting the electronic components on the electronic circuit board. 
         [0140]    This disclosure describes embodiments of a sensor including an electronic circuit board that can be inserted outside in from the exterior wall of a faucet through a receiving hole. The features of the sensor assembly and methods described herein can also be implemented in other systems and devices with similar size restrictions. 
         [0141]      FIG. 14  illustrates an exploded view of a sensor  2400  that can be mounted to the faucet from outside in through a receiving hole. The sensor  2400  includes a lens  2414  that can be attached to a cover  2408 . In some embodiments, the lens  2414  and the cover  2408  are formed of the same material in the same step. In other embodiments, the lens  2414  is separately formed from the cover  2408  and later coupled together. In some embodiments, the lens  2414  is a different material than the cover to take advantage of differing properties. 
         [0142]    In some embodiments, the lens  2414  can be secured to the outside wall of the faucet. The cover  2408  can include a securing module  2406  to mount the sensor  2400  in position with the faucet. The securing module  2406  can be an expandable clip as shown in  FIG. 14 . In other embodiments, the sensor can be secured with a retaining structure that is affixed to the inner wall of the faucet. In yet other embodiments, the sensor can be installed outside in and secured with a snug fit receiving hole, a gasket, glue, adhesive agent, and/or clips. The sensor can also include a sleeve  2412  that provides a barrier or a partition between the emitter  2416  and the detector  2420  to reduce noise. The detector and emitter can fit within holes  2410  of the sleeve  2412  which can also help stabilize the detector and the emitter. The sensor  2400  can also include a rim or a flange  2404 . The rim  2404  can be an extension of the cover  2408  or the lens  2414  or a separate component that can be attached to the cover  2408 . The flange  2404  can be larger than the receiving hole to prevent the sensor from falling inside the faucet while the securing module  2406  can work in conjunction with the flange  2404  to prevent the sensor from falling out of the faucet. The flange  2404  can be mounted flush with the faucet body as shown in  FIG. 15B . The sensor can also include further securing attachments to hold the sleeve and the electronic circuit board  2432  in place. The sensor components may also be secured with glue or other adhesive agents. 
         [0143]      FIG. 14  further illustrates an embodiment of an electronic circuit board  2432  that can be used with a sensor  2400  installed outside in through a receiving hole. The dimensions of the electronic circuit board  2432  are such that the electronic circuit board  2432  can fit through the receiving hole. In some embodiments, the dimensions of the electronic circuit board  2432  are substantially the same as the dimension of the receiving hole. In other embodiments, the dimensions of the electronic circuit board  2432  are smaller than the dimensions of the receiving hole. In yet another embodiment, the dimensions of the electronic circuit board  2432  are smaller than the dimensions of the sensor cover. The electronic circuit board  2432  can be secured to the sensor cover  408 . In some embodiments, the electronic circuit board  2432  can be secured directly to the faucet. As described above, when the size of the electronic circuit board  2432  is reduced to make it fit through the receiving hole, the smaller size can result in a limited space for mounting the electronic components  2428  (e.g. capacitors, resistors, emitters, detectors, LEDs, ICs etc.). There may also not be enough room for the wire connecting holes  2430 . 
         [0144]    As shown in the illustrated embodiment in  FIG. 14 , to increase available surface area on the electronic circuit board  2432 , the emitter  2416  and the detector  2420  can be elevated from the surface of the electronic circuit board  2432 . Accordingly, the space taken by the base  2422  of the detector  2420  and the base  2418  of the emitter  2416  can be used for other electronic components. In some embodiments, the emitters and detectors are mounted at a distance away from the surface of the electronic circuit board  2432  with the use of one or more legs (or stilts)  2424  and  2426 . The height of the legs may depend on the size of the electronic components  2428 . The legs may provide both structural and electrical connection for the emitters and detectors to the electronic circuit board  2432 . In some embodiments, the legs may include female connectors for receiving emitters and detectors. The legs may be a separate unit or built-in as part of the emitters and detectors. Separate leg units may provide more stability in certain embodiments than using built-in legs for the emitters and detectors. However, in some embodiments of the sensor  2400 , emitters and detectors with stock built-in legs can also be used to mount the emitter and the detector at a distance away from the surface of the circuit board  2432 . In some embodiments, the legs  2424 ,  2426  are attached to the electronic circuit board  2432  via one or more hinged connections. In some such embodiments, the circuit board  2432  can be inserted through the receiving hole while rotated with respect to (e.g., non-perpendicular with respect to) the legs  2424 ,  2426 . In some such embodiments, one or more dimensions of the circuit board  2432  can be the same as or larger than the corresponding dimensions of the receiving hole while permitting insertion of the rotated circuit board  2432  through the receiving hole. 
         [0145]      FIG. 15A  illustrates a side view of an embodiment of a sensor  2400  installed outside in through the receiving hole  2104  of a faucet wall  2106 . As shown, the rim  2404  of the sensor  2400  can rest against the edge of the receiving hole  2104  to prevent the sensor  2400  from falling inside the faucet or other assembly to which the sensor is mounted. For example, the sensor could be mounted into a housing that is separate from a faucet so as to more effectively position the sensors relative to the water flow section of the faucet and the water receiving basin. The sensor  2400  can include a securing module  2406  to prevent the sensor from falling out of the faucet and secure the sensor  2400  in a substantially fixed position with respect to a wall  2106 . The securing module  2406  can include a retaining clip which can expand after insertion of the sensor  2400  in the receiving hole  2104 . In some embodiments, including the illustrated embodiment, the sensor can include two securing modules  2406  on opposite sides for securing the sensor  2400 . In some embodiments, one, or three or more securing modules  2406  can be used to secure the sensor  2400 . The legs  2424  and  2426  can create a distance  2502  between the surface of the electronic circuit board  2432  and the emitter and detector. Accordingly, the base of the detector and emitter can be on a separate plane from the surface of the electronic circuit board  2432 .  FIG. 15  further shows electronic components  2428  (e.g. capacitors, resistors, and ICs) mounted on both the top and bottom of the electronic circuit board  2432  and in between the legs  2424 ,  2426  of the emitter and the detector. Thus, the surface area typically occupied by the bases  2418 ,  2422  of the emitter  2416  and the detector  2420  is occupied by the necessary electronic components, allowing an overall reduction of the surface board space to fit within the necessary restraints to allow outside in insertion through the receiving hole  2104  of the wall  2106 . 
         [0146]      FIG. 15B  illustrates a side view of an embodiment of a sensor  2400  installed outside in through the receiving hole  2104  of a wall  2106  with the rim  2404  mounted flush with the surface  2504  of the faucet wall  2106 . 
         [0147]    Other ways may be incorporated to meet the surface area demands of these sensors while still permitting outside in insertion of the sensor assembly through a receiving hole. For example, in some embodiments, the sensor  2400  can also include a multi-level electronic circuit board (not shown) to increase surface area. For example, the emitters and detectors can be installed on a higher level while the electronic components can be installed in the lower levels. The back side of the higher level can also be used for electronic components. In another embodiment, the sensor  2400  can include a flexible electronic circuit board (not shown). Flexible electronic circuit boards can be bent so that the electronic circuit board of a size larger than the receiving hole may be used. 
         [0148]      FIG. 16  illustrates a top view of an embodiment of a sensor  2400  that can be inserted from outside in through a receiving hole  2104 . The securing modules  2406  are shown in the expanded position. The edge or rim  2404  of the sensor can sit on a groove  2620  of the receiving hole  2104 . The groove  2620  of the receiving hole can be indented from the surface of the outer wall  2106  of the faucet. Thus, in some embodiments, the sensor  2400  can be mounted flush with the outer wall  2106 . In an embodiment, the sensor  2400  may include a sealer opening  2610  in the sensor cover  2408 . The sealer opening  2610  can be used to insert a sealer into the sensor assembly  2400 . The sealer can be a type of glue that turns hard or semi-hard after injection. The sealer can be injected into the assembly to seal and fill the gap between the sensor cover, sleeve, emitter, detector, circuit board and other components of the sensor described herein. In some embodiments, the glue can secure the sensor to the faucet without needing securing modules. Wire  2434  can connect to a logic processor (not shown). 
         [0149]      FIG. 17  illustrates a bottom surface  2702  of an embodiment of an electronic circuit board  2432  with holes  2430  for receiving legs of the emitter and the detector. Wires  2434  can be soldered to connect the electronic circuit board  2432  with a logic processor. 
         [0150]      FIG. 17A  illustrates an embodiment of a sensor  3800  wherein both the emitter  3816  and the receiver  3820  are surface-mount devices (e.g., SMDs) to facilitate easy installation and/or low cost for the sensor  3800 . 
         [0151]      FIGS. 17B-17E  illustrate an embodiment of a sensor  3900  wherein the sensor electronic circuit board  3932  can be removably connected to an interconnect circuit board  3940  via a plug  3906  and socket  3907 . As illustrated, the sensor  3900  can include an emitter  3916  (e.g., an infrared LED, an SMD type LED, and/or other emitter) and a receiver  3920  (e.g., an infrared LED phototransistor, an SMD type LED phototransistor, and/or other receiver). The emitter  3916  and receiver  3920  can be mounted on or otherwise connected to the sensor circuit board  3932 . Additional electronic components  3928  can be attached to one or both sides of the sensor circuit board  3932  in some embodiments. 
         [0152]    In some embodiments, the sensor  3900  includes a sensor cover  3902 . The sensor cover  3902  can be sized and shaped to fit over the emitter  3916  and/or over the receiver  3920 . In some embodiments, the sensor cover  3902  is sized and shaped such that at least a portion of the sensor circuit board  3932  fits within the interior of the sensor cover  3902 . The sensor  3900  can include a sensor sleeve  3912 . The sensor sleeve  3912  can have a plurality of apertures extending through the sensor sleeve  3912 . In some embodiments, the emitter  3916  is positioned within an aperture of the sleeve  3912  separate from the receiver  3920 . 
         [0153]    The sensor  3900  can include an interconnect circuit board  3940  (e.g., a PCB). The interconnect circuit board  3940  can be housed at least partially within a circuit board housing  3936 . In some embodiments, the interconnect circuit board  3940  is attached to the housing  3936  via adhesives, welding, fasteners, and/or some other attachment structure or method. The housing  3936  can be coupled to the faucet body  2016  via clips, adhesives, and/or some other structure or method. For example, the housing  3936  can be coupled to the faucet body  2016  using any of the clips  2804 ,  2902 ,  2904 ,  2906 ,  3210 ,  3302 ,  3320  described below. In some embodiments, the housing  3936  is positioned (e.g., wedged) against the faucet body  2016  via a rubber block. The interconnect circuit board  3940  can include one or more sockets  3907 . The sockets  3907  can include one or more recesses or slots. 
         [0154]    In some embodiments, the interconnect circuit board  3940  is configured to facilitate electronic communication (e.g., signals, data, power) between the sensor circuit board  3932  and other components of a faucet assembly. For example, the interconnect circuit board  3940  can include one or more cable connector points  3950 . The cable connector points  3950  can be configured to electronically communicate with components such as, for example, a main circuit board, a control unit, or some other component of the faucet assembly. 
         [0155]    As illustrated in  FIGS. 17B, 17E, and 17F , the plug  3906  can be connected to the sensor circuit board  3932  through an opening in the faucet body  2106 . The plug  3906  can include one or more prongs configured to couple with the recesses or slots in the socket  3907 . In some embodiments, friction between the plug  3906  and the socket  3907  can inhibit or prevent accidentally decoupling of the sensor circuit board  3932  from the interconnect circuit board  3940 . 
         [0156]    In some embodiments, a sealant  3954  (e.g., an adhesive, polymer, elastomeric material, and/or some combination of materials) can be used in the assembled sensor  3900 . For example, as illustrated in  FIG. 17F , the sealant  3954  can be installed in the sensor cover  3902  on an underside of the sensor circuit board  3932 . The sealant  3954  can inhibit ingress of water or other fluids into the sensor cover  3902  and/or into contact with electrical components of the sensor circuit board  3932 . In some embodiments, the sealant  3954  couples the sensor circuit board  3932  to inhibit or prevent accidental removal of the sensor circuit board  3932  from the sensor cover  3902 . In some embodiments, the interconnect circuit board housing  3936  includes a sealant  3954  to inhibit or prevent water damage to the interconnect circuit board  3940  and/or to inhibit or prevent accidental decoupling of the interconnect circuit board  3940  from the circuit board housing  3936 . 
         [0157]      FIG. 17G  illustrates an embodiment of a faucet assembly  4000  having a plurality of sensors  4002   a,    4002   b,    4002   c,    4002   d,    4002   e  (hereinafter referred to collectively as sensors  4002 ). As illustrated, one or more of the sensors  4002  can be connected to one or more interconnecting circuit boards  4006  through openings in the walls  4004  of the faucet assembly  4000 . For example, one or more pairs of sensors  4002  can be connected to a single interconnecting circuit board  4006 . The sensors  4002  can be connected to the circuit boards  4006  via, for example, plug-socket fittings  4010  similar to or the same as those described above with respect to sensor  3900 . In some embodiments, one or more of the sensors  4002  is connected to its respective circuit board via a 4-prong plug, a 6-prong plug, an 8-prong plug, and/or any other suitable plug. 
         [0158]    The interconnecting circuit boards  4006  can be housed within respective interconnecting circuit board housings  4014 . One or more of the housings  4014  can include a cable connector point  4018 . For example, one or more of the housings  4014  can include a cable connector point  4018  configured to electronically connect one or more of the sensors  4002  and/or interconnecting circuit boards  4006  to a master circuit board. 
         [0159]    As illustrated in  FIG. 17G , the faucet assembly  4000  can include a hub circuit board  4008  housed within a master circuit board housing  4016 . In some embodiments one or more sensors  4002  (e.g., sensor  4002 e) can be connected to the hub circuit board  4008  via a plug-socket fitting  4010 . The hub circuit board housing  4016  can include one or more sensor cable connector points  4022  configured to facilitate electronic communication between the hub circuit board  4008  and the cable connector points  4018  of the interconnecting circuit board housings  4014 . For example, wires cables  4024  (e.g., 5 wire cables) can connect the respective connector points  4018 ,  4022 . In some embodiments, the hub circuit board housing  4016  includes a main connector point  4026  configured to electronically connect to an electronic component (e.g., the main circuit board) of the faucet assembly  4000  via, for example, a wire cable  4028  (e.g., a 10 wire cable). 
         [0160]      FIGS. 17H and 17I  illustrate an embodiment of a sensor  4100  wherein the sensor electronic circuit board can be removably connected to a wire  4134  via a plug  4106  and socket  4107 . The sensor  4100  can include an emitter  4116  (e.g., an infrared LED, an SMD type LED, and/or other emitter). As illustrated, the sensor  4100  can include a receiver  3920  (e.g., an infrared LED phototransistor, an SMD type LED phototransistor, and/or other receiver). The emitter  4116  and/or the receiver  4120  can be mounted on or otherwise connected to the sensor circuit board  4132 . Additional electronic components  4128  can be attached to one or both sides of the sensor circuit board  4132  in some embodiments. 
         [0161]    In some embodiments, the sensor  4100  includes a sensor cover  4102 . The sensor cover  4102  can be sized and shaped to fit over the emitter  4116  and/or over the receiver  4120 . In some embodiments, the sensor cover  4102  is sized and shaped such that at least a portion of the sensor circuit board  4132  fits within the interior of the sensor cover  4102 . The sensor cover  4102  can include one or more slits  4104  or other connection structures configured to facilitate connection of the sensor cover  4102  to a faucet body (not shown) (e.g., the faucet body  2016 ). For example, a clip (not shown) (e.g., one or more of the clips  2804 ,  2902 ,  2904 ,  2906 ,  3210 ,  3302 ,  3320  described below) may be used to connect the sensor cover  4102  to a faucet body. 
         [0162]    The sensor  4100  can include a sensor sleeve  4112 . The sensor sleeve  4112  can have a plurality of apertures extending through the sensor sleeve  4112 . In some embodiments, the emitter  4116  is positioned within an aperture of the sleeve  4112  separate from the receiver  4120 . 
         [0163]    In some embodiments, the plug  4106  is a 4-prong plug, a 6-prong plug, an 8-prong plug, and/or any other suitable plug. The socket  4102  can be a 4-recess socket, 6-recess socket, 8-recess socket, and/or any other suitable socket for connecting to the plug  4106 . Use of a plug and socket engagement can facilitate easy installation and/or removal of the sensor  4100  from the wire  4134 . 
         [0164]    As illustrated in  FIG. 17H , the socket  4107  can be connected to a wire  4134 . For example, the wire  4134  can be soldered or otherwise permanently or releasably connected to the socket  4107 . The wire  4134  can connect the socket  4107  to a logic processor (not shown) or other electrical component. In some embodiments, the wire  4134  connects the socket  4107  to an interconnect circuit board (not shown) (e.g., a PCB). 
         [0165]      FIG. 18  illustrates an embodiment of a sensor  2800  with a securing module  2804  that includes retaining pins. As shown, the sensor  2800  can be inserted outside in such that the rim  2802  may rest on the edge of the wall  2106  near the receiving hole  2104  as described above to prevent the sensor from falling in. The securing modules  2804  can further secure the sensor  2800  from falling out of the wall. In the illustrated embodiment, two retaining pins  2804  are inserted in grooves  2806  of the sensor cover  2808  along the inner surface of the wall  2106  to prevent the sensor from dislodging. The pins  2804  can be installed from the interior of the faucet. The length of the pin may depend on the thickness of the wall. The pins may also be shaped to match the curvature of the wall  2106 . In some instances, the pins may be bendable. In certain embodiments, it may be advantageous to use pins or clips instead of screws because they may be easily installed and removed. Thus, pins or clips can also make repairs possible as it might be easier to pull pins out and remove the sensor as described more in detail with respect to  FIGS. 26A and 26B . 
         [0166]      FIGS. 19A-C  illustrate several embodiments of retaining pins  2902 ,  2904 ,  2906  that can secure the sensor  2800  as discussed above with respect to  FIG. 18 . 
         [0167]      FIG. 20  illustrates a side view of an embodiment of an electronic circuit board  3010  including an IR emitter  2416 , a light emitting diode  3002 , and a detector  2420 . The legs (not shown) can create a distance  2502  between the base of the emitters or detector and the surface of the electronic circuit board  2432 . The increased distance can create additional surface area for mounting electronic components. The light emitting diode  3002  may emit visible radiation. Adding the light emitting diode  3002  may increase the length of the sensor by 3 to 5 mm. 
         [0168]      FIG. 21  illustrates an embodiment of a process for installing a sensor described above from outside in through the receiving hole of a faucet. In an embodiment, the method begins at block  3110 , where a cable including one or more wires is inserted into a faucet through a receiving hole of a faucet. The cable can be inserted either from the interior of the faucet and removed out of the receiving hole or inserted into the receiving hole from outside and into the interior of the faucet. The wires can connect the electronic circuit board with a logic processor. At block  3112 , the wires can be connected to the electronic circuit board as described above. In an embodiment, the electronic circuit board, including any electrical circuit elements, emitters and/or detectors, can be assembled with a sensor cover. The sensor assembly including the sensor cover can be inserted outside in through the receiving hole at block  3114 . The sensor cover can also include securing modules. In some embodiments, the securing modules are separate components from the sensor cover. At block  3116 , the securing modules can be engaged to secure the sensor in the receiving hole. The securing modules can automatically deploy or engage in some instances when the sensor is inserted in the receiving hole. In some embodiments, the securing modules are installed after the sensor is inserted in the receiving hole. For example, retaining pins described above can be used to secure the sensor. 
         [0169]      FIG. 22A  illustrates another embodiment of a sensor  3200  that can be installed from outside into a faucet. The sensor  3200  includes a sensor cover  3202  with one or more slits  3204 . The sensor  3200  can be secured to the faucet using one or more clips  3210  shown in  FIG. 22B . The clip  3210  can be bent or twisted to secure the sensor  3200  with the faucet.  FIGS. 23A  and B illustrate top and side view of the sensor  3200  shown in  FIG. 22A . The dimensions of the clip  3210  can be a function of the wall thickness and/or wall curvature. The clip  3210  may be made of metal, plastic, or some other suitable material (e.g., a resilient material, a flexible material, and/or a rigid or semi-rigid material). 
         [0170]      FIG. 23C  illustrates an embodiment of a clip  3302  for securing the sensor  3200  to the faucet. The clip can include a center portion  3304  and edge portions  3306 . In an embodiment, the width of the center portion can be proportional to the size of the sensor  3200  such that the center portion engages the grooves of the sensor cover  3202  as shown in  FIG. 24 . The edge portions  3306  can be bent or twisted towards the inner wall of the faucet as shown in  FIG. 25 . The degree of twist and dimensions of the clip may be a function of the faucet wall thickness  3310  and the spacing  3308  as illustrated in  FIG. 25B . In some embodiments, the length of the sensor is in the range of 10 to 50 mm, the width in the range of 6 to 20 mm, and depth in the range of 5 to 20 mm. Dimensions of the sensor may a function of aesthetics as well as utility. Accordingly, in certain embodiments, the clip  3302  can prevent the sensor  3200  from falling out of the faucet. 
         [0171]      FIG. 23D  illustrates a top view of another embodiment of the clip  3320  that includes notches  3326  for use in the installation process of a sensor. In some embodiments, the notches can advantageously prevent the clip  3320  from slipping out of the grooves. The clip  3320  includes a center portion  3324  and two edge portions  3322 . The edge portions  3324  can be angled from the center portions  3324  such that the edge portions  3324  can engage with a wall of the faucet. In some embodiments, the edge portions  3322  are compressed against the wall to secure a sensor.  FIG. 23E  illustrates a side view of the clip  3320 . As illustrated, there is height gap  3328  between the center portion  3324  and the edge portion  3322 . The gap  3328  can depend on the size of the sensor and the dimension of the faucet. In some embodiments, the clip may be made of stainless steel or other metallic material with some compressibility. In other embodiments, the clip may be made of a plastic material or a combination of metallic and plastic materials. 
         [0172]      FIGS. 26A-B  illustrate an embodiment of an installation tool  3610  for use in installation of securing modules such as clips  3302  and  3320  with the sensors. The installation tool  3610  can fit inside the faucet structure to slide the clips into the grooves  3204  of the sensor  3200 . The handle  3612  of the installation tool  3610  may be of a size smaller than the size of the faucet. This may allow all or at least a substantial portion of the handle to reach inside the faucet for attaching the clip  3302  with the sensor  3200 . The arm extender  3614  extends from the handle  3612 . In some embodiments, the arm extender  3614  has a curvature and may also taper away from the handle  3612 . The curvature may enable the tool  3610  to slide inside of faucets of varying sizes including tapered faucets. The length of the arm extender  3614  may depend on the length of the sensor  3200 , the length of the grooves, or the length of clip  3302  such that the clip  3302  can be completely secured along the sensor. 
         [0173]    In the illustrated embodiment shown in  FIG. 26B , the installation tool  3610  includes two arms  3616  and  3618  to engage the looped or the center portion  3304  of the clip  3302 . The arms  3616  and  3618  can be spaced apart according to the size of the sensor  3200  such that there is sufficient distance to slide the clip  3302  through the grooves  3204 . The spacing between the arms  3616  and  3618  may also be wider than the center portion  3304  of the clip  3302  to stretch the clip  3302  along the center portion  3304  during the installation process. The tension in the clip  3302  as a result of the stretch may ensure that the clip  3302  does not fall from the installation tool  3610 . When the installation tool  3610  is disengaged, the clip  3302  may snap back to secure the sensor  3200  along the grooves  3204 . As shown, the arm  3616  is shaped to engage the clip  3302  from the top and the arm  3618  is shaped to also engage the clip  3302  from the top such that pressure against the clip from both sides feeds the clip around the sensor. The positions and/or shape of the arms  3616  and  3618  may depend on the structural features of the clip and can also be configured such that one portion of the clip is hooked from the top and the other portion is hooked from the bottom. The curvature of arm extender  3614  may increase the longitudinal rigidity of the extender such that less material is needed to form a sufficiently rigid installation tool. The arms  3616  and  3618  are preferably sufficiently rigid such that they can also be used to engage the center portion  3304  of the clip  3302  to facilitate removal of the clip to facilitate sensor replacement and/or repair. In some instances, the tool  3610  may hook on to the center portion  3304  during removal of the clip  3302  from the sensor  3200 . 
         [0174]    An embodiment of an installation process of the clip  3302  with the sensor  3200  is described below. A manufacturer or other user can engage the clip  3302  with the installation tool  3610  as shown in  FIG. 26B . The manufacturer can then slide the installation tool  3610  engaged with the clip  3302  inside the faucet. The edge portions  3306  of the clip  3302  may face towards the wall of the faucet during the installation process. The sensor  3200  can be inserted from outside in through the receiving hole as described above. Once the clip passes around the sensor  3200  along the grooves  3204 , the manufacturer can unhook the clip  3302  from the installation tool  3610 . The unhooking process may depend on the shape of the arms  3616  and  3618  and the clip  3302 . For the illustrated configuration shown in  FIG. 26B , the manufacturer can lift, wiggle, or rotate the installation tool  3610  to disengage the clip  3302  from the arms  3616  and  3618 . The manufacturer can then remove the installation tool  3610  out of the faucet. In some embodiments, the installation tool  3610  may include a mechanism (e.g. spring) to expand the clip while sliding into the grooves  3204  and then release before sliding out. In certain embodiments, it may be advantageous to use clip  3320  with notches  3326  so that after securing the clip to the sensor, the installation tool  3610  can be disengaged and removed while keeping the clip secured with the sensor. The notches  3326  may follow the curvature of the sensor and snap in when clip  3320  is installed. The notches  3326  can prevent the clip from slipping out when removing the installation tool from the faucet. In certain embodiments, the notches  3326  enable the clip  3320  to fit snug with the sensor  3200  to secure the assembly. 
         [0175]      FIGS. 27A-B  illustrate another embodiment of an installation tool  3710  for use in installation of securing modules such as clips  3302  and  3320  with the sensors. The installation tool includes a handle  3712 , an arm extender  3714 , an inner arm  3716  and an outer arm  3718 . The installation tool  3710  has a longer cut size  3720  as compared to the installation tool  3610  described above. In some embodiments, the cut size  3720  is a function of the size  3724  of the sensor  3200  so that the clip  3302  can fit entirely across the sensor. In some embodiments, the width of the cut size  3720  is equal to or greater than the width of the sensor as measured between the innermost portion of the grooves  3204 . 
         [0176]      FIG. 28  illustrates another embodiment of a hybrid faucet system  5100 . Some numerical references to components in  FIG. 28  are the same as or similar to those previously described for the faucet system  100  (e.g., spout  5104  v. spout  104 ). Unless otherwise noted, like numbers (e.g.,  102  v.  5102 ,  106  v.  5106 , etc.) refer to features which are similar or the same. 
         [0177]    As illustrated, the hybrid faucet system  5100  can include a first valve  5120  to control flow rate of water from a first water inlet  5128 . In some embodiments, the system  5100  includes a second vale  5118  configured to control flow rate of water from a second water inlet  5130 . The first and second water inlets  5128 ,  5130  can be a hot and cold water inlets, respectively. In some embodiments, the first and second water inlets  5128 ,  5130  are cold and hot water inlets, respectively. Adjustment of the flow rate through the separate valves  5120 ,  5118  can adjust both the overall flow rate of water to the mixed water flow  5134  and can adjust the temperature of the water in the mixed water flow  5134 . In some such embodiments, a separate flow rate valve is not necessary to control flow rate to the motor valve  5122 . In some embodiments, a solenoid can be used in addition to or instead of or in addition to a motor. 
         [0178]    In some embodiments, the valve  5120  includes a valve handle  5110  configured to adjust a mechanical valve component. For example, as discussed in more detail below with respect to  FIG. 31 , the valve handle  5110  can be configured to rotate a valve cylinder  5300  to control hot or cold water flow into the faucet system  5100 . In some embodiments, the valve  5118  includes a handle  5108 . The handle  5108  can be configured to adjust a mechanical valve component such as, for example, a valve cylinder  5352 . 
         [0179]      FIGS. 29-30  illustrate another embodiment of a hybrid faucet system  5100 A. Unless otherwise noted, like numbers between the hybrid faucet system  5100 A and the system  5100  described above refer to features which are similar or the same. 
         [0180]    Referring to  FIGS. 29 and 30 , the system  5100 A can include a check valve  5121  positioned upstream of the valve  5120 . In some embodiments, the system  5100 A includes a check valve  5119  positioned upstream of the valve  5118 . The check valves  5121 ,  5119 , alone or in combination, can inhibit or prevent water of one temperature (e.g., either hot or cold) from accessing the inlet of the water of the other temperature. For example, the check valve  5121  can inhibit or prevent water from the inlet  5130  (e.g., hot water) from accessing the water inlet  5128  (e.g., the cold water inlet). The check valve  5119  can be configured to inhibit or prevent water from the inlet  5128  (e.g., cold water) from accessing the water inlet  5130  (e.g., the hot water inlet). 
         [0181]    As illustrated in  FIG. 31 , the flow and temperature control valve assembly  5300  can include a first valve cylinder  5302  and a second valve cylinder  5352 . The two cylinders can be rotatable with respect to each other (e.g., via rotation of the handles  5110 ,  5108 ). One or both of the valve cylinders  5302 ,  5352  can include a water inlet  5310 ,  5360 . In some embodiments, one of the water inlets (e.g.,  5360 ) is configured to receive hot water from the hot water inlet  5130 . The other water inlet (e.g.,  5310 ) can be configured to receive cold water from the cold water inlet  5128 . Rotation of the valve cylinders  5302 ,  5352  can change the flow rates through the inlets  5310 ,  5360  by increasing or decreasing an overlap portion between the inlets  5310 ,  5360  and apertures upstream of the inlets  5310 ,  5360 . 
         [0182]    One or both of the valve cylinders  5302 ,  5352  can include a water outlet  5137  (e.g., cold water outlet),  5135  (e.g., hot water outlet). The water outlets  5137 ,  5135  of the respective cylinders  5302 ,  5352  can be positioned at ends of the cylinders opposite the grooves  5302 ,  5362  or other handle-engagement members of the valves  5120 ,  5118 . The water outlets  5137 ,  5135  can direct water from the valve cylinders  5302 ,  5352  to the mixed water flow  5134 . 
         [0183]    Referring to  FIGS. 32 and 33 , a valve system  5101  of the hybrid faucet system  5100 A can include a pair of fluid connectors  5176 ,  5177  connected to the cold water inlet  5128  and hot water inlet  5130 , respectively. One or both of the hot water inlet  5130  and cold water inlet  5128  can be located in an inlet housing  5174 . The check valves  5119 ,  5121  can be positioned in the respective fluid paths between the fluid connectors  5177 ,  5176  and the valve cylinders  5352 ,  5302 . 
         [0184]    Each of the valve handles  5110 ,  5108  can be inserted at least partially into valve cylinder housings  5172 ,  5173 . In some embodiments the handles  5110 ,  5108  are connected to the housings  5172 ,  5173  via set screws  5170 ,  5171 . The handles  5110 ,  5108  can engage the respective cylinders  5302 ,  5352  in a rotationally-locked manner (e.g., via engagement with the slots  5302 ,  5362  of the cylinders  5302 ,  5352 ). Screws  5190 ,  5191  can be inserted into the housings  5172 ,  5173 . The screws  5190 ,  5191 , or some other structure of the valve system  5101 , can engage with grooves  5304 ,  5354  of the respective cylinders  5302 ,  5352  to limit the permissible range of rotation of the cylinders  5302 ,  5352 . 
         [0185]      FIG. 34  illustrates an embodiment of a hybrid faucet system  5100 B which can be the same as the system  5100  described above, with the addition of a second sensor  5114 . The second sensor  5114  can perform various functions. For example, the second sensor  5114  can be configured to operate in a manner similar to, or the same as, the sensor  114  described above. 
         [0186]      FIG. 35  illustrates an embodiment of a hybrid faucet system  5100 C which can be the same as the system  5100 A described above, with the addition of a second sensor  5114 . The second sensor  5114  of the system  5100 C can operate in the same or a similar mode as the second sensor  5114  of the system  5100 B. 
         [0187]    FIGURS  36 - 37  illustrate an embodiment of a hybrid faucet system  5100 D that can be the same as or similar to any of the faucet systems  5100 ,  5100 A,  5100 B, or  5100 C described above. The system  5100 D includes a second sensor  5722  positioned on a top surface  5708  of the faucet body  5102 . In some embodiments, the second sensor  5722  is configured to operate in a manner similar to, or the same as, either or both of sensors  114  and  722  described above. 
         [0188]      FIGS. 38-41  illustrate an embodiment of a valve system  6000 . The valve system  6000  can share many structural and/or functional features with the valve system  5101  described above. As illustrated, the valve system  6000  can include a step motor  6036 . The step motor  6036  can be configured to open and close the valve system  6000 . In some embodiments, the step motor  6036  is configured to operate in response to input from one or more sensors of a faucet system such as those faucet systems described above, and accordingly, is configured to operate in one or more of the faucet systems above. Though illustrated with particular shapes and designs, the various components of the valve system, including the valve head and the seat, can be any of a variety of designs that fit in the desired system. 
         [0189]    In some embodiments, the step motor  6036  controls a valve assembly  6030 . The valve assembly  6030  can be configured to permit or restrict fluid flow between water inlets  6076 ,  6077  and a water outlet channel  6038 . 
         [0190]    In some embodiments, the valve assembly  6030  includes a linear actuator (not illustrated) connected to a valve head  6037 . The linear actuator can be controlled by the step motor  6036 . In some embodiments, the step motor  6036  is connected to the valve head  6037  via an actuator rod  6040 . The step motor  6036  can be configured to move the valve head  6037  upward and downward (e.g., in the frame of reference of  FIGS. 39 and 41 ) and into and out of contact with a valve seat  6020 . One or more of the valve head  6037  and valve seat  6020  can include O-rings  6009  or other sealing structures. In some embodiments, the valve assembly  6030  includes a rotational actuator instead of or in addition to the linear actuator. The rotational actuator can impart rotational movement to the valve head  6037  to affect fluid flow through the valve system  6000 . 
         [0191]    Referring to  FIG. 39 , the valve system  6000  can include a first water inlet hose (e.g., a hot water inlet hose)  6077  and a second water inlet hose (e.g., a cold water inlet hose)  6076 . One or more valve cylinders  6052 ,  6002  can be positioned downstream from the inlet hoses  6076 ,  6077 . The valve cylinders  6052 ,  6002  can be housed at least partially within cylinder housings  6072 ,  6073 . In some embodiments, the valve cylinders  6052 ,  6002  are similar or identical in function and/or structure as the valve cylinders  5352 ,  5302  described above. In some embodiments, a check valve  6019  is positioned in the flow path between the inlet hose  6077  and the flow cylinder  6052 . In some embodiments, a check valve  6021  is positioned in the flow path between the inlet hose  6076  and the flow cylinder  6002 . The check valves  6019 ,  6021  can be the same as or similar in function as the check valves  5119 ,  5121  described above. 
         [0192]    The step motor  6036  can be connected to the housing of the valve system  6000  via fasteners, welding, adhesive, friction fitting, threaded engagement, and/or any other method or connecting structure. As illustrated in  FIGS. 38 and 41 , the step motor  6036  can be mounted to the housing via a mounting plate  6042  and fasteners. In some embodiments, a mounting assembly  6041  facilitates connection between the step motor  6036  and the valve housing  6075 . In some embodiments C-clips, pin(s), or other connection structures can facilitate connection between the mounting assembly  6041  and the valve housing  6075 . As illustrated in  FIG. 41 , the mounting assembly  6041  can include a C-clip lock hole(s)  6047 . The C-clip lock holes  6047  in the mounting assembly  6041  can align with C-clip lock hole(s)  6047   a  ( FIG. 42 ) in the valve housing  6075 . In some applications, the step motor  6036  is mounted at a top end of the valve mounting assembly  6041 . 
         [0193]    Comparing  FIG. 39  with  FIG. 41 , the valve head  6037  can transition between an open position ( FIG. 39 ) and a closed position ( FIG. 41 ). In the open position, a fluid can flow through a gap  6010   a  between the valve head  6037  and the valve seat  6020 . In the closed position, fluid can be prevented from flowing between the water transition channel  6032  and the water outlet channel  6038  due to a seal  6010   b  between the valve head  6037  and the valve seat  6020  (e.g., a seal which may be supplemented by one or more O-rings, such as O-ring  6009 ). In some embodiments, the valve assembly  6030  can be configured to meter flow between the channels  6032 ,  6038  via motion of the valve head  6037  with respect to the valve seat  6020 . For example, the valve head  6037  can be positioned at a plurality of positions between the open position illustrated in  FIG. 39  and the closed position illustrated in  FIG. 41 . In some embodiments, the valve head  6037  can be positioned at an infinite number of positions between the closed and open positions. In some embodiments, the closer the valve head  6037  is to the valve seat  6020 , the lower the fluid flow rate permitted through/around the valve head  6037 . 
         [0194]    The step motor  6036  can be fluidly separated from the fluid flow path of the valve system  6000  via one or more seals/sealing structures. For example, one or more O-rings  6045  in the mounting assembly  6041  or other portions of the valve system  6000  can be used to fluidly isolate the step motor  6036  from fluid. 
         [0195]      FIGS. 43-46  illustrate an embodiment of a valve system  7000 . The valve system  7000  can share many structural and/or functional features with the valve system  6000  described above. As illustrated, the valve system  7000  can include a step motor  7036 . The step motor  7036  can be configured to open and close the valve system  7000 . In some embodiments, the step motor  7036  is configured to operate in response to input from one or more sensors of a faucet system such as those faucet systems described above, and accordingly, is configured to operate in one or more of the faucet systems above. Though illustrated with particular shapes and designs, the various components of the valve system, including the valve head and the seat, can be any of a variety of designs that fit in the desired system. 
         [0196]    In some embodiments, the step motor  7036  controls a valve assembly  7030 . The valve assembly  7030  can be configured to permit or restrict fluid flow between water inlets  7076 ,  7077  and a water outlet channel  7038 . 
         [0197]    In some embodiments, the valve assembly  7030  includes a linear actuator (not illustrated) connected to a valve head  7037 . The linear actuator can be controlled by the step motor  7036 . In some embodiments, the step motor  7036  is connected to the valve head  7037  via an actuator rod  7040 . The step motor  7036  can be configured to move the valve head  7037  upward and downward (e.g., in the frame of reference of  FIGS. 44 and 46 ) and into and out of contact with a valve seat  7020 . As illustrated, the valve head  7037  may seal the valve seat  7020  when in an upper-most position ( FIG. 46 ) and may unseal from the valve seat  7020  in a lower position ( FIG. 44 ). One or more of the valve head  7037  and valve seat  7020  can include O-rings or other sealing structures. As illustrated in  FIG. 43 , the valve head  7037  can include a sealing portion  7039 . The sealing portion  7039  can be positioned (e.g., sandwiched) between two washers  7046  and two nuts  7044 . In some embodiments, the sealing portion  7039  is a flexible and/or elastomeric disc. In some embodiments, the valve assembly  7030  includes a rotational actuator instead of or in addition to the linear actuator. The rotational actuator can impart rotational movement to the valve head  7037  to affect fluid flow through the valve system  7000 . 
         [0198]    Referring to  FIG. 44 , the valve system  7000  can include a first water inlet hose (e.g., a hot water inlet hose)  7077  and a second water inlet hose (e.g., a cold water inlet hose)  7076 . One or more valve cylinders  7052 ,  7002  can be positioned downstream from the inlet hoses  7076 ,  7077 . The valve cylinders  7052 ,  7002  can be housed at least partially within cylinder housings  7072 ,  7073 . In some embodiments, the valve cylinders  7052 ,  7002  are similar or identical in function and/or structure as the valve cylinders  5352 ,  5302  described above. In some embodiments, a check valve  7019  is positioned in the flow path between the inlet hose  7077  and the flow cylinder  7052 . In some embodiments, a check valve  7021  is positioned in the flow path between the inlet hose  7076  and the flow cylinder  7002 . The check valves  7019 ,  7021  can be the same as or similar in function as the check valves  5119 ,  5121  described above. 
         [0199]    The step motor  7036  can be connected to the housing of the valve system  7000  via fasteners, welding, adhesive, friction fitting, threaded engagement, and/or any other method or connecting structure. As illustrated in  FIGS. 43 and 46 , the step motor  7036  can be mounted to the housing via a mounting plate  7042  and fasteners. In some embodiments, a mounting assembly  7041  facilitates connection between the step motor  7036  and the valve housing  7075 . In some embodiments C-clips, pin(s), or other connection structures can facilitate connection between the mounting assembly  7041  and the valve housing  7075 . As illustrated in  FIG. 46 , the mounting assembly  7041  can include a C-clip lock hole(s)  7047 . The C-clip lock holes  7047  in the mounting assembly  7041  can align with C-clip lock hole(s) (not shown) in the valve housing  7075  in a manner similar to that illustrated in  FIG. 42 . In some applications, the step motor  7036  is mounted at a top end of the valve mounting assembly  7041 . 
         [0200]    Comparing  FIG. 44  with  FIG. 46 , the valve head  7037  can transition between an open position ( FIG. 44 ) and a closed position ( FIG. 46 ). In the open position, a fluid can flow through a gap  7010   a  between the valve head  7037  and the valve seat  7020 . In the closed position, fluid can be prevented from flowing between the water transition channel  7032  and the water outlet channel  7038  due to a seal  7010   b  between the valve head  7037  and the valve seat  7020  (e.g., a seal which may be supplemented by one or more O-rings or sealing structures such as the sealing portion  7039 ). In some embodiments, the valve assembly  7030  can be configured to meter flow between the channels  7032 ,  7038  via motion of the valve head  7037  with respect to the valve seat  7020 . For example, the valve head  7037  can be positioned at a plurality of positions between the open position illustrated in  FIG. 44  and the closed position illustrated in  FIG. 46 . In some embodiments, the valve head  7037  can be positioned at an infinite number of positions between the closed and open positions. In some embodiments, the closer the valve head  7037  is to the valve seat  7020 , the lower the fluid flow rate permitted through/around the valve head  7037 . 
         [0201]    The step motor  7036  can be fluidly separated from the fluid flow path of the valve system  7000  via one or more seals/sealing structures. For example, one or more O-rings  7045  in the mounting assembly  7041  or other portions of the valve system  7000  can be used to fluidly isolate the step motor  7036  from fluid in the housing  7075 . 
         [0202]    Although several embodiments, examples and illustrations are disclosed below, it will be understood by those of ordinary skill in the art that the inventions described herein extends beyond the specifically disclosed embodiments, examples and illustrations, and can include other uses of the inventions and obvious modifications and equivalents thereof. In particular, several embodiments are described with respect to installing a sensor in a faucet. However, there are many instances where sensors may need to be installed from outside in of a structure. For example, in some instances, there may be a secondary structure housing all the sensors to control operation of the flow of water separate from a faucet. Sensors can also be used to control light and other electronics. The methods and apparatuses described herein can also be used to secure sensors in various retaining structures (e.g. lamp, light switches, etc.). As a further example, the hot and cold water lines  5128 ,  5130  may be switched within any of the faucet systems described above without compromising the functionality of the hybrid faucet systems. The terminology used in the description presented herein is not intended to be interpreted in any limited or restrictive manner simply because it is being used in conjunction with a detailed description of certain specific embodiments of the inventions. In addition, embodiments of the inventions can comprise several novel features and no single feature is solely responsible for its desirable attributes or is essential to practicing the inventions herein described. 
         [0203]    Certain terminology may be used in the following description for the purpose of reference only, and thus are not intended to be limiting. For example, terms such as “above” and “below” refer to directions in the drawings to which reference is made. Terms such as “proximal,” “distal,” “front,” “back,” “rear,” and “side” describe the orientation and/or location of portions of the components or elements within a consistent but arbitrary frame of reference which is made clear by reference to the text and the associated drawings describing the components or elements under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and words of similar import. 
         [0204]    It should be emphasized that many variations and modifications may be made to the herein-described embodiments, the elements of which are to be understood as being among other acceptable examples. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims. Moreover, any of the steps described herein can be performed simultaneously or in an order different from the steps as ordered herein. Moreover, as should be apparent, the features and attributes of the specific embodiments disclosed herein may be combined in different ways to form additional embodiments, all of which fall within the scope of the present disclosure. 
         [0205]    Conditional language used herein, such as, among others, “can,” “might,” “may,” “e.g.,” and the like, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or states. Thus, such conditional language is not generally intended to imply that features, elements and/or states are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without author input or prompting, whether these features, elements and/or states are included or are to be performed in any particular embodiment. The terms “comprising,” “including,” “having,” and the like are synonymous and are used inclusively, in an open-ended fashion, and do not exclude additional elements, features, acts, operations, and so forth. Also, the term “or” is used in its inclusive sense (and not in its exclusive sense) so that when used, for example, to connect a list of elements, the term “or” means one, some, or all of the elements in the list. In addition, the articles “a” and “an” are to be construed to mean “one or more” or “at least one” unless specified otherwise. 
         [0206]    Conjunctive language such as the phrase “at least one of X, Y and Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to convey that an item, term, etc. may be either X, Y or Z. Thus, such conjunctive language is not generally intended to imply that certain embodiments require at least one of X, at least one of Y and at least one of Z to each be present.