Patent Publication Number: US-2023141834-A1

Title: Dryer

Description:
This application claims priority benefit of Provisional Application No. 63/278,372 filed Nov. 11, 2021, which is hereby incorporated by reference in its entirety. 
    
    
     FIELD 
     The present application relates generally to hand dryers. 
     BACKGROUND 
     Hot air operated hand dryers have been available for over half a century. In recent decades, the major advancement has been high velocity air jets which can substantially dry hands in 10-15 seconds even without adding heat. This is accomplished by the force of air stripping water from the skin, mostly mechanically rather than by evaporation. The energy, cost, and cleanliness compared to paper towels has been researched, debated and published in a variety of articles. Both have unique advantages, hence both jet dryers and paper towels exist based on preferences or biases. For example, in some studies, the energy and cost of using jet dryers was considerably lower than paper towels. In other cases, the initial cost of jet dryers may be a hurdle. Specific hygienic concerns of a hospital or waste management concerns of an arena or small establishment may influence the decision to use a jet dryer or paper towels. 
     In very recent times, the concern about airborne microbes has become heightened. The hygiene of jet dryers is being debated based on the perception that high velocity air jets can detach microbes from surfaces and significantly mobilize germs in a room. The research and publications are divided on proving this concern, but the possibility is real. 
     Most of the conventional devices deliver air jets onto the hands from a perpendicular direction causing water and air to splash in every direction including onto a wall and onto the user. Conceivably, splashing can initiate biofilm formation and promote growth on surfaces, and air jets deflected by hands could dislodge biofilms. Furthermore, most of the air jets are delivered into the washroom space with no substantial containment, thus increasing the fear about spread of germs. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Exemplary embodiments are described herein with reference to the following drawings, according to an exemplary embodiment. 
         FIG.  1    illustrates an example hand dryer. 
         FIG.  2 A  illustrates example cyclones for the hand dryer of  FIG.  1   . 
         FIG.  2 B  illustrates a top view of the hand dryer of  FIG.  1   . 
         FIG.  3 A  illustrates an example air knife for the hand dryer of  FIG.  1   . 
         FIG.  3 B  illustrates an example air knife for the hand dryer of  FIG.  1   . 
         FIG.  4 A  illustrates a position of the air knife with respect to a duct of the hand dryer. 
         FIGS.  4 B and  4 C  illustrate a position of the air knife with respect to a horizonal. 
         FIGS.  5 A and  5 B  illustrate another embodiment of a hand dryer. 
         FIGS.  6 A and  6 B  illustrate another embodiment of a hand dryer. 
         FIG.  7    illustrate a cross section of the hand dryer of  FIGS.  6 A and  6 B . 
         FIGS.  8 A and  8 B  illustrate another embodiment of a hand dryer including an expansion chamber. 
         FIG.  9    illustrates another arrangement of air knives for a hand dryer. 
         FIG.  10    illustrates another arrangement of air knives for a hand dryer. 
         FIGS.  11 A and  11 B  illustrate another arrangement of air knives for a hand dryer. 
         FIGS.  12 A and  12 B  illustrate a circular air duct with a vacuum source for a hand dryer. 
         FIGS.  13 A and  13 B  illustrate another embodiment of a hand dryer. 
         FIGS.  14 A and  14 B  illustrate another embodiment of a hand dryer. 
         FIGS.  15 A and  15 B  illustrate another embodiment of a hand dryer. 
         FIG.  16    illustrates an example hand dryer according to any of the embodiments herein mounted in association with a sink. 
         FIG.  17    illustrates a cutaway view of the example of  FIG.  16   . 
         FIG.  18    illustrates multiple hand dryers according to any of the embodiments herein integrated with a sink. 
         FIG.  19    illustrates multiple hand dryers according to any of the embodiments herein integrated with a sink and cabinet. 
         FIG.  20    illustrates an example controller for any of the dryer systems of  FIGS.  1 - 19   . 
         FIG.  21    illustrates an example flow chart for the controller of  FIG.  20   . 
     
    
    
     DETAILED DESCRIPTION 
     The following embodiments include air dryers (e.g., hand dryers) that include a ducted cavity and at least one air knife angled into the ducted cavity. The ducted cavity, as well as the angle and orientation of the at least one air knife, is arranged to apply the jet or jets of air to a single hand of the user. The at least one air knife may be provided in a vertical direction to apply to the single hand of the user in a “handshake” position. In this way, the air is provided to both sides of the hand simultaneously. Some examples include a cyclone device in which the air in the ducted cavity rotates for the removal of water droplets, aerosols, or other particles. The particles may be propelled against the walls of the cyclone device, where they can be easily removed, sanitized, disinfected, or otherwise cleaned. The cyclone may connect to an exhaust path so that the air, water, aerosols, and other particles are provided to another space (i.e., away from users in the bathroom). Additional examples include an expansion chamber to slow the flow of air in the ducted cavity. These components, arranged in this manner to dry a single hand of the user, operate with low power requirements. The air dryer may user smaller motors and fans than similar two-hand dryers. In addition, the vertical arrangement (“handshake” position of the hand) allows for versatility in both the height of the air dryer (mounting position) and the height of the user. 
       FIG.  1    illustrates an example hand dryer or air dryer system  100  including at least one air knife  101  and a ducted cavity. The air knife  101  may include an aperture  103  and a fan  110 . The fan  110  generates an airflow through the hollow portion of the air knife  101 , which tapers to the thin aperture  103 , causing an increase in the velocity of the air flow. The fan  110  may generate a predetermined flow rate such as 25 cubic feet per minute or greater. As an alternative to the aperture  103 , a series of holes may be used. The fan  110  may be separated from the air knife  101  through a hose or sealed passage. 
     As an example of the operation principle of an air knife, when used in manufacturing settings, an air knife may be mounted along a conveyer belt on which a product or other object travels. The air knife emits a high-intensity, uniform sheet of laminar airflow to dry the objects (i.e., mechanically strip or remove water from the objects). In the enclosed embodiments, the air knives direct such a uniform sheet if laminar air flow onto an object such as the user&#39;s hands that are held in the air flow. The hands may be moved in a particular pattern or direction (e.g., into the dryer, in a vertical plane, in a vertical plane and away from the user, in a vertical plane and into the dryer, in a direction perpendicular to the air flow, or another direction). An indicia on the outside of the hand dryer may instruct the user in the particular pattern or direction. 
     The ducted cavity may include at least one cyclone device  102  or cyclonic device and an inlet air path between the air knives  101 . The air inlet path may be defined on each side by a side wall  107  and on the top wall  106 . Thus, the inlet air path may be defined on three sides, including two side walls  107  and the top wall  106 . An open space or gap may be present between lower portions of the air knives  101 . It should be noted that no bottom wall is included in certain embodiments. As illustrated in  FIG.  1   , only one side wall  107  on the left side is illustrated, but a symmetrical side wall  107  may also be present on the right side as well. The side walls may be different shapes and inclined in any direction. The cyclone devices  102 , or an associated housing, may be secured to a wall or other structure by brackets  108  via screws, bolts, or other fasteners. The space between the air knives  101  may be open on the bottom (that is not bottom wall). This is because water is substantially prevented from dripping due to the orientation of the air knives. Any water that does drip is allowed to fall freely, thus avoiding any pooling water or accumulated moisture as much as possible. The cyclone devices  102  may include a drain  115  (e.g., a nozzle and/or pan) for accumulation of water and/or expulsion of water from the cyclonic devices  102 . Additional, different, or fewer components may be included. 
     The ducted cavity may also be defined by an entry plate  105  that connects the cyclone device  102  to the side wall  107 . The entry plate  105  may be coupled to the cyclone device  102  via a fastener or adhesive. A divider  109  (shown in  FIG.  4 A ) in one or more of the cyclone devices may form cyclone inlet  104 . Air from the air knives  101  flows into the cyclone device  102  through the cyclone inlet  104 . 
     Between the side walls  107  is a drying space where an object is placed between the air knives  101  for drying. The object may be one or more of a user&#39;s hands. The hands may be placed at a predetermined angle, which is guided by the shape and orientation of the drying space. The air knives  101  may be mounted at a predetermined angle (e.g., a predetermined angle in up to three directions or measured from any combination of three axes) that optimizes or maximizes the drying of the object. The air knife  101  driven by the fan  110  directs air to dry one or more hands and push water from the one or more hands into the ducted cavity. 
     The hand dryer  100  may be configured to dry a single hand at a time. The space between the air knives  101  may be narrow and sized for a single hand. The air knives  101  provide the jets of air to the two sides of the single hand simultaneously. In some examples, one hand is placed in the hand dryer  100  for a time period and then the other hand is placed in the hand dryer  100  for a time period. In some embodiments, the system includes two hand dryers  100  placed at a comfortable distance a part so that a left hand is placed in the left hand dryer at the same time that a right hand is placed in a right hand dryer. 
     The hand dryer  100  is shaped and orientated so that the exhaust air that is expelled by the hand dryer  100  is captured by the cyclones  102  to separate water and slow the air down to be exhausted away from the user. The orientation of the air knives  101  and drying cavity allows the user to place the user&#39;s hands substantially straight out using ergonomics similar to that of a handshake. The air knives  101  may be oriented so that no water splashes outside of the hand dryer  100 , as described through the disclosed embodiments. 
     A controller  10  may send commands, provide power to, or otherwise operate the fan  110  for driving the air knife  101 . The controller  10  may be couped to a sensor  12 . The sensor  12  is configured to generate sensor data for an object in vicinity to the hand dryer. The sensor  12  may be a proximity sensor that detects an object, such as the user&#39;s hands in proximity to the hand dryer. For example, the sensor  12  may detect the user&#39;s hands within a predetermined distance to the air knife  101  or within the drying space. The sensor  12  may detect another object or a gesture made by the user. In some examples, the sensor may include any type of sensor configured to detect certain actions. A proximity sensor may be employed to detect the presence of an object within a zone of detection without physical contact between the object and the sensor. Electric potential sensors, capacitance sensors, projected capacitance sensors, light detection and ranging (LiDAR), and infrared sensors (e.g., projected infrared sensors, passive infrared sensors) are non-limiting examples of proximity sensors that may be employed with the systems of this application. Motion sensors may be employed to detect motion (e.g., a change in position of an object relative to the objects surroundings). Electric potential sensors, optic sensors, radio-frequency (RF) sensors, sound sensors, magnetic sensors (e.g., magnetometers), vibration sensors, and infrared sensors (e.g., projected infrared sensors, passive infrared sensors) are non-limiting examples of motion sensors that may be employed with the systems of this application. In another example, the sensor may include a time of flight (ToF) or a LiDAR that servers as a proximity sensor. The controller  10  receives sensor data and analyzes the sensor data to determine when a user is approaching or has approached the hand dryer. The controller  10  turns on the air knife  101  and/or fan  110  in response to the analysis of the sensor data. A mechanical button, switch, or sensor may be used rather than a touchless sensor. 
     The controller  10  may implement a timer or be coupled to a timer  11 . The timer may count to an elapsed time period. The time period may be an amount of time after the user&#39;s hand, or another object are no longer detected by the sensor  12  before the controller  10  instructs the fan to turn off. In one example, the controller  10  may also turn off if a maximum time limit is reached by the timer  11  since the fan  110  was turned on. 
     In some examples, the controller  10  turns on the air knife  101  and/or fan  110  turns on in response to the detection of the user&#39;s hand(s) by the sensor  12  and turns off the air knife and/or the fan  110  in response to the elapsed time passing after the user&#39;s hand(s) are no longer detected. Thus, the controller  10  is configured to operate the fan  110  to move air through the hand dryer in response to the sensor data or the elapsed time period. The controller  10  may start the fan to in response to the sensor data and stops the fan in response to the elapsed time period. 
     The controller  10  may operate in a low flow rate mode to clean the room air. For example, even when no user&#39;s hands or objects are present in the dryer space, the controller  10  may operate the fan  110  to circulate air from the room into the hand dryer for any of the disinfecting, sanitization, or cleaning techniques described herein. The controller  10  may start the low flow rate mode at a predetermined time (e.g., at 2 AM or other overnight time period, or during a weekend) as determined by the timer  11 . The controller  10  may be loaded with a schedule or calendar for the low flow rate mode. An external button (e.g., user input device  355 ,  FIG.  20   ) may trigger the low flow rate mode. In some examples, the sensor  12  includes an air quality sensor and the controller  10  triggers the low flow rate mode in response to data from the air quality sensor. 
       FIG.  2 A  illustrates example cyclones  102  for the hand dryer of  FIG.  1   . The air and water is driven through the ducted cavity and around the cyclones  102 , which applies a force to the water including aerosols or other particles to the outside of the cyclones  102 . As discussed in more detail below, the particles adhere to the radial surfaces of the cyclones  102 . 
     In some examples, the cyclones  102  are covered or otherwise enclosed on the top and air is vented to escape through the bottom of the cyclones  102  (as shown in  FIG.  2 A ). In other examples, the cyclones  102  are covered or otherwise enclosed on the bottom and air is vented to escape through the top of the cyclones  102 . In other examples, the cyclones  102  may be vented on both the top and the bottom so that air can escape on both the bottom. In addition or in the alternative, vents may be included on the sides of the cyclones. The vents may direct the air to another room, inside the wall, or a ventilation system. 
     The cyclones  102  may include two concentric channels including an inner channel  112  and an outer channel  113 . The cyclones  102  may be formed of two cylinders such that the inner channel  112  passes through the inside of an inner cylinder and the outer channel  113  passes between the inner cylinder and the outer cylinder. Air passes from the air knife  101  into the ducted cavity and past the divider  109  as shown by arrow A into the outer channel  113 . One or more holes or windows  114  connect the outer channel  113  to the inner channel  112 . As shown by arrow B, the air flows through the windows  114  from the outer channel  113  into the inner channel  112 . A gap G defines the height of the windows  114  or a distance between the edge of the inner channel  112  to the end plate of the cyclone  102 . The gap G may be varied to regulate the volume of air (e.g., flow rate or speed) flowing from the outer channel  113  to the inner channel  112 . As described below, the gap G and associated flow rate may be selected according to disinfection technique, or another treatment applied to the air in the inner channel  112 . As shown by arrow C, the air the flows through the inner channel  112  to the vent. 
     The inner cylinder forms a baffle that forces the air flow to at least partially flow around the inner cylinder in at least a partially circular path for the air and water from the user&#39;s hand. The term circular may describe the cross-section of the inner cylinder and/or the outer cylinder. The term circular may describe the up and down or serpentine path through the inner and outer channels. 
     The inner cylinder forms a baffle that forces the air flow to at least partially flow around the inner cylinder in at least a partially circuitous path for the air and water from the user&#39;s hand. The term circuitous may describe the change in direction from the inner cylinder to the outer cylinder. Other shapes besides cylinders may be used. That is, the inner cylinder and the outer cylinder may be rectangular, square, oval, or another shape in cross section. 
     In addition, or in the alternative, other baffles such as in the radial or longitudinal direction with respect to the inner cylinder. Other flaps, channels, labyrinths or passages may be included to ensure that the path of the air is long enough for the water droplets and aerosols to be removed by centrifugal force. The particles expelled from the air and water adhere to cyclone device  102 . In some examples, the inside surface of the cyclone device  102  may be textured to facilitate the adherence. In some examples, the moisture that accumulated on the inside surface of the cyclone device  102  facilitates the adherence. 
     Other examples are possible for the construction for the cyclones  102  may include another number of concentric channels. Three channels, four channels, or more may be utilized. In some example, the channels have different heights. That is, one of the channels may be a proportion (e.g., half) of the height of one or more other channels. 
     In one example, the air flows from the duct to a first outer channel. Air passes from the air knife  101  into the ducted cavity and past the divider  109  as shown by arrow A into the outer channel. From the outer channel, air passes to a first inner channel through one or more windows or apertures. From the first inner channel, air passes to a second inner channel through one or more windows or apertures. Any number of channels may be used. The channels may have a variety of heights. The channels may have a variety of relative diameters or widths. For example, the first inner channel may have a diameter that is a predetermined proportion or percentage of the outer channel (e.g., 80%) and the second inner channel may have a diameter that is a predetermined proportion or percentage of the first inner channel (e.g., 80%). 
     In some examples, the air flow from the duct first flows upward through the outer channel  113  into the inner channel  112  and downward through the inner channel  112 . In other examples, the air flow from the duct flows downward through the outer channel  113  into the inner channel  112  and upward through the inner channel  112 . In the case of three channels, the air flow may substantially travel upward through the outer channel, downward through the first inner channel, and upward through the second inner channel. Alternatively, the air flow the air flow may go downward through the outer channel, upward through the first inner channel, and downward through the second inner channel. 
     Once the aerosols or other particles are adhered to the inside surface of the cyclone device  102 , one or more disinfectants or disinfecting techniques are applied to the particles within the cyclone device  102 . 
     In one example, a light such as ultraviolet light is mounted in the cyclone device  102 , or adjacent to the cyclone device  102  through a window. The ultraviolet light irradiates the internal walls. The ultraviolet light may have a predetermined frequency or wavelength, which may be a range of wavelengths or frequencies for the light emitted from the light. The germicidal irradiation may be optimized by a wavelength band of 200 to 280 nanometers (nm) other examples may include 200 to 222 nm, 230 to 250 nm, 240 to 315 nm or other ranges. An example wavelength may be 254 nm. The controller  10  may send commands to the light to turn on the light or stop the light. The controller  10  may send commands to the light to set the wavelength of the light. The ultraviolet light disinfects the particles. The ultraviolet light may kill or eliminate living organisms (e.g., bacteria) and/or viruses that are adhered to the inside surface of the cyclone device  102  or otherwise contained in the cyclone device  102  (e.g., in a mist). Ultraviolet light may be run for at least 30 seconds after a user has finished using the hand dryer. In high use cases ultraviolet light may be run continuously. This option may be set up by the building operator, or it may be done by machine learning or other artificial intelligence (AI). 
     In one example, a liquid or suspended disinfectant may be sprayed or dispersed into the cyclone device  102 . The disinfectant may be hydrogen peroxide (H 2 O 2 ), chlorine, citric acid, electrolyzed water, or ozone (O 3 ). The hydrogen peroxide may be stored in a tank that is refilled by the user or a service technician. The ozone may be generated by a corona charger that ionizes the air in or around the cyclone device  102  using a high voltage that causes the air to breakdown and become conductive. The corona occurs when the potential gradient of the electric field around the charger is greater than the dielectric strength of the air. When ozone is used there is an option of adding ultraviolet (UV) decomposition phase after ozonation. A short UV irradiation phase will decompose the ozone and reduce the amount of ozone that escapes the hand dryer. 
     The gap G between the outer channel  113  and the inner channel  112  may be set according to the type of treatment. In one example, treatment from UV light may be associated with a lower flow rate (larger gap G) and treatment from a sprayed or atomized mist may be associated with a higher flow rate (smaller gap G). 
     The controller  10  may operate a disinfectant dispenser configured to provide the disinfectant to the cyclone device  102 . The dispenser may include a nozzle or sprayer that may be electronically actuated by the controller  10 . The controller  10  may operate the charge to generate the ozone within or adjacent to the cyclone device  102 . 
     The controller  10  may operate an ultrasonic emitter to provide ultrasonic waves to the cyclone device  102 . The ultrasonic emitter may include an ultrasonic atomizer or transducer that converts high frequency sound waves into mechanical energy that is transferred into standing waves of the sanitizing liquid, causing a mist or fog to be emitted. 
     The controller  10  may operate in a sanitation mode to release a sanitizer into the hand dryer. The sanitation mode may occur after the drying mode. For example, after a predetermined has elapsed from drying, the sanitation mode is started by the controller  10 . During the sanitation mode, any of these techniques (e.g., ultraviolet light, ozone generation, disinfectant dispensing, ultrasonic wave generation) may be performed under commands from the controller  10 . The sanitation mode may be performed at periodic intervals or at predetermined times of day or days of the week. The sanitation mode may be performed in response to the sensor data (i.e., after the drying mode) and/or in response to an elapsed time period (i.e., a certain amount of time after the drying mode has started or ended). 
       FIG.  2 B  illustrates a top view of the hand dryer of  FIG.  1   .  FIG.  2 B  illustrates that the cyclone devices  102  are to the rear of the air knives  101  and the top plate  106 . The cyclone devices  102  and the air knives  101  may be fastened or adhered (e.g., glued) to the top plate  106 . 
     A predetermined distance, or dryer width W, defines a distance between the side walls  107  or between the centers of the air knives  101 . The width W may be width of the ducted cavity. The width may define the proximity of the air knives  101 , and corresponding air jets, to the one or more hands. The distance between the air knives  101  and the one or more hands impacts the speed and effectiveness of the air to remove water from the one or more hands. It is beneficial to cause the user to bring the one or more hands as close as possible to the air knives  101  while also providing sufficient space for relatively large hands and at the same time providing enough space for the user to easily avoid touching the sides of the ducted cavity. In several embodiments, the width is selected for a single hand so that the single hand is in close proximity to both air knives  101  but far enough apart for the user to maintain a comfortable distance between the air knives  101 . A range for the width W is 2 to 4 inches or 2.750 to 3.125 inches. An example selected width W may be 3 inches. 
     In any of the examples described herein, one or more filters may be included upstream of the hand dryer, within the hand dryer, and/or downstream of the hand dryer. The filtering may be provided in addition to or in the alternative of the sanitization and disinfection techniques described herein. The upstream air filter may be coupled to the fan so that all air traveling through the fan has been filtered. The filter within the hand dryer may be upstream of the air knife  101 , in the ducted cavity, or in the cyclone device  102 . The filter downstream of the hand dryer may be at the air exhaust of the hand dryer. Any of these filters, to the extent room air is circulated, may be a room filter configured to filter air in the vicinity of the apparatus. 
     Any of these filters are configured to remove particles from the air. The filter may be a pleated mechanical air filter such as HEPA (high efficiency particulate air filter). The filter may be a separation filter based on particle size. The filter may include activated carbon. 
     The filter may be an electrostatic separator. For example, an electrostatic aerosol collector is biased with a voltage to provide the electrostatic charge. The voltage may be a low voltage that avoids the risk of shock. In some embodiments, the electrostatic aerosol collector is charged through the physical properties of the material. In some embodiments, electrostatic aerosol collector is charged through frictionally moving two components together. In order to maintain the electrostatic charge on the plastic sheet, the sides, edges, or corners may be insulated. The insulation may include non-conductive materials between the plastic sheet and the wall or other devices. 
     In any of these examples a hand disinfectant dispenser  90  may be included adjacent to or coupled with the hand dryer. The hand disinfectant dispenser  90  may be automatically (e.g., by electronic control from the hand dryer controller or a proximity sensor) or manually (e.g., by push button or gesture) actuated to dispense disinfectant on the hands of the user. When automatically controlled, the hand disinfectant dispenser  90  may be actuated before, during, or after the fan  110  is actuated. 
     In a first example, the controller  10  may receive sensor data indicative of a user is approaching or has approached the hand dryer, and the controller  10  turns on the hand disinfectant dispenser  90  before turning on the air knife  101  and/or fan  110 . In a second example, the controller  10  may receive sensor data indicative of a user is approaching or has approached the hand dryer, and the controller  10  turns on the hand disinfectant dispenser  90  simultaneous (or near simultaneous within a predetermined time period) to turning on the air knife  101  and/or fan  110 . In a third example, the controller  10  may receive sensor data indicative of a user is approaching or has approached the hand dryer, and the controller  10  turns on the hand disinfectant dispenser  90  after turning on the air knife  101  and/or fan  110 , after turning off the air knife  101  and/or the fan  110 , or after a predetermined time delay. 
       FIG.  3 A  illustrates an example air knife  101  for the hand dryer of  FIG.  1    having a curved or angled aperture  103 . The aperture  103  may have a predetermined width or air knife gap K. Examples for the gap K may be in the range of 0.01 to 0.05 inches. One example gap K is 0.03 inches. The size of the gap K affects the speed and force of the air. Smaller gaps greater an air knife with a higher force that quickly strips water from a hand. However, if the gap K is too small, and the corresponding force is too high, the air knife may feel too strong to the user. 
       FIG.  3 B  illustrates an example air knife  101  for the hand dryer of  FIG.  1    having a straight or linear aperture  103 . The linear aperture  103  may also have a selectable or variable aperture  103  having gap K. The gap K may be varied by an adjustment screw that brings one plate of the air knife  101  closer together or father apart from a second plate of the air knife  101 . 
       FIG.  4 A  illustrates a top down view of the hand dryer including a position of the air knife  101  with respect to a duct of the hand dryer. For example,  FIG.  4 A  illustrates that an angle α 1  of the air knife aperture  103  may be angled at an acute angle with respect to the side wall  107 , which may be aligned with a horizontal plane H. In one example, the angle α 1  between the knife aperture  103  and the horizontal plane may be in a range of 45 to 60 degrees. One specific example angle α 1  may be 55 degrees. The angle α 1  may be selected to maximize the amount of air that is directed into the duct of the hand dryer. When the angle α 1  is too low the intersection point of the air flows from the knife apertures  103  is too far inside the duct to effectively strip water from the same object (user&#39;s hand). When the angle α 1  is too high, air may be deflected from the wrist of the hand. Higher angles may also result in resonant tones and vibrations. 
     As the predetermined angle is increased, the air knife  101  is pointed more into the ducted cavity to push the air and water into the dryer but less direct drying force is applied to the user&#39;s hands. The angle may be selected to maximize the speed and effectiveness of drying as well as forcing the air and water into the dryer. 
     The predetermined angle (e.g., 55 degrees) may act to self-center the user&#39;s hand(s) in the hand dryer. The flow of air from the air knives  101  may apply forces to the user&#39;s hand(s) that are substantially balanced. Shorter angles may cause forces having a larger perpendicular force against the user&#39;s hand(s) that tends to push the user&#39;s hand(s) against the side wall  107 . 
       FIGS.  4 B and  4 C  illustrate a position of the air knife  101  with respect to a horizonal. The incline, or angle with the horizontal plane, of the air knife  101  may affect the angle that water is pushed off the user&#39;s hands. When the angle with the horizontal plane is at a first angle α 2  which may be substantially perpendicular (e.g., 90 degrees), drying may be maximized when the user moves hands at an angle. When the angle with the horizontal plane is a second angle α 3 , which may be an acute angle (e.g., 70 degrees), drying may be maximized when the user moves hands up and down. 
       FIGS.  5 A and  5 B  illustrate another embodiment of a hand dryer. In this example, the air knives  101  are inclined toward the front of the hand dryer  100  and the apertures  103  are pointed inward to push air and water into the cyclones  102 . In this example, a single construction (e.g., molded material or deformable material) is shaped to form integrated cyclones  102  and air ducts, including at least one cyclone input  104  and at least one cyclone output  116 . The cyclone output  116  may open into a space below the hand dryer  100 . The cyclone output  116  may be connected to a tube or duct that directs the exhaust air to a predetermined location. The cyclone output  116  may be exhausted to another room or into a heating or ventilation system. 
       FIGS.  5 A and  5 B  further illustrate the vertical arrangement of the air knives  101  allowing the “handshake” orientation of the single hand in the vertical plane so that both air knives  101  provide air jets to the single hand. The air knives  101  are inclined down and away from the user as well as pointed in so that the water stripped from the single hand is pushed immediately toward the cyclones  202 . Because the air knives  101  are on opposite sides of the hand, water does not “roll” from one side of the hand to the other. Instead, the water is pushed forward into the cyclones  202 . Because of the vertical space for the single hand to be inserted into the hand dryer  100 , users of varying heights, even users that may need to reach up or above their heads to reach the hand dryer  100 , can comfortably place hands in the vertical plane between the air knives  101 . For similar reasons, the hand dryer  100  may be mounted at a variety of heights while accommodating all users. 
       FIGS.  6 A,  6 B, and  7    illustrate another embodiment of a hand dryer  100 .  FIG.  7    illustrates a cross section of the hand dryer of  FIGS.  6 A and  6 B . The hand dryer  100  of this embodiment may include any of the components of other embodiments described herein. This hand dryer may include vertical space so as to be operable to dry one hand or two hands simultaneously. The hand dryer includes a housing  120  including one or more air jets  201  with corresponding pressure chambers  203  connected to a fan chamber  204 . Air from the air jets  201  enters a drying chamber for drying the user&#39;s hands and then enters a cyclonic separator  202 . Additional, different, or fewer components may be used. 
     Referring to  FIG.  6 A , the air jets  201  are angled to sweep over hands as they enter and exit the slot of the drying space horizontally or vertically. Further the air jets  201  are directed toward the interior of the duct away from the user. Referring to  FIG.  6 B , the air jets  201  are supplied by a common fan supplying the pressure chamber  203 . As the air jet is deflected from the hand, it is directed toward the interior wall which divides the flow into two passages. Each of the passages are the inlet to the cyclonic separator  202 . 
     A window  211  may provide an optical path between the fan chamber  204  and the cyclonic separator  202 . An ultraviolet light  210  may be mounted in proximity to the window  211 . The ultraviolet light  210  may transmit UV light into the cyclonic separator  202  to disinfect the air and water traveling through the cyclonic separator and received from the drying duct. 
     Referring to  FIG.  7   , the air flow enters through a slot in the cyclonic section  202 , and after several turns exits through an opening directed toward the floor. The cyclonic section  202  separates air and water and slows the velocity of exhaust. The cyclonic section  202  has an upturned air exit to trap water which can be routed to a drain or collected in a container. 
     For the example of a single-handed device, the hand dryer may dry objects rapidly by using high velocity air jet, but the motor may be smaller, thus produce less noise. Further, requiring less volume flow can reduce the mobilization of microbes. In addition, the complete device can be smaller and lower in cost. 
       FIGS.  8 A and  8 B  illustrate another embodiment of a hand dryer with a ducted dryer for drying two hands simultaneously. The hand dryer includes a plurality of air knives  131  arranges on multiple drying spaces  135  or ducts (e.g., a first space  135  for a left hand and a second space  135  for a right hand). The air knives  131  may be angled inward (e.g., 55 degrees) to the spaces  135 . The hand dryer includes a fan section  133  including a fan and a pressure chamber  132  that is pressurized by the fan to provide the air flow to the air knives  131 . Out of the drying spaces  135 , the air and any suspended water, aerosols, or other particles are provided to an expansion chamber  137 , with an increased volume that slows down the flow. 
     For the hand dryer of  FIGS.  8 A and  8 B , the hand orientation is vertical and arm orientation is extended with slight bend at the elbow. These ergonomics provides for a range of user heights. The ducts are sized to accept hands larger than 99th percentile male. Each duct delivers high velocity air jets to both sides of the hands. The air jets are angled into the duct such that the jet will impinge on the hands with sufficient pressure to remove water while also deflecting further into the duct. This action eliminates splash back onto the user. The direction of the air jet or air knife  131  is controlled by nozzles in a pressure chamber  132  supplied by a common fan. After the air passes through the duct, it enters an enclosed chamber (e.g., expansion chamber  137 ) of significantly larger volume to slow the flow velocity. A diffuser  134  may be configured diffuse the flow to separate air and water and further slow the velocity. The final exit is directed downward to the floor away from the user. The separated water can be collected and routed to a drain or container. 
       FIG.  9    illustrates another arrangement of air knives  101  for a hand dryer. In this example, two air knives  101  may be arranged in parallel one behind the other. A vacuum  141  may draw the air from the air knives  101  across the drying space into the ducted cavity. A hand dryer with two or more air knives  101  may be faster, dryer, utilize a lower air velocity, create less noise, and produce more air entrainment to protect a user. With individually controllable air knives, different velocities may be selected (e.g., low air, high air). Higher velocities for the outer knives help to remove water from the skin, and higher flow rates on the inner knives carry droplets to the collection system. 
       FIG.  10    illustrates another arrangement of air knives  101  for a hand dryer. In this example, multiple (e.g., five) air knives  101  may be arranged in varying angles and generally directed to an internal point toward vacuum  141 . 
       FIGS.  11 A and  11 B  illustrate another arrangement of air knives  101  for a hand dryer. A curved air knife  101  may be angled so that all parts of the air knife  101  are pointed toward the vacuum  141 . Air blades may have a compound angle in the arc (approximately 30 degrees from the horizontal) with an air knife velocity of 100-200 m/s. The vacuum  141  may include a flow rate of about 50 cubic feet per minute (CFM) and may match or exceed the flow rate of the air knifes in aggregate. 
       FIGS.  12 A and  12 B  illustrate a circular air duct  150  with a vacuum source  141  for a hand dryer. One or more air knives  101  are mounted at the inlet of the circular air duct  150 . The user&#39;s hand or hands are placed at the inlet of the circular air duct  150 . The circular air duct  150  provides a circular path for the air, water, and suspended particles. The water may be collected at the collection device  142  at the bottom of the circular air duct  150 . A drain may be provided to empty the collection device  142 . 
       FIGS.  13 A and  13 B  illustrate another embodiment of a hand dryer with a drying air source  160 , air curtains  162  and walls  161 . The air curtains  162  are thin jets of air (e.g., as provided by air knives) that provide air walls within the hand dryer.  FIG.  13 A  illustrates that the air curtain  162  is positioned behind the user&#39;s hand(s) and configured to wash bacteria, water, and other particles away from the user and toward the wall  161 . An interior wall  171  may direct the air curtain  162 . 
       FIG.  13 B  illustrates that the air curtain  162  provides a vertical barrier between the user&#39;s hand(s) and the wall  161 . In this way, any water, bacteria, or other particles being blows toward the wall  161  will not be reflected off of the wall. The air curtain  162  prevents the bacteria from getting blown off the wall from the hand dryer. 
       FIGS.  14 A and  14 B  illustrate another embodiment of a hand dryer coupled with a vacuum  170 . The vacuum  170  may be positioned behind the hand (e.g., upstream of opening  177 ), at a level substantially similar to the hand (e.g., shown in  FIG.  14 A ), and/or at any lower position in the hand drying chamber (e.g., shown in  FIG.  14 B ). In  FIG.  14 A  a vacuum  170  is placed in the wall  161  to pull the air, water, bacteria, or other particles out of the hand dryer and into the wall  161 . The exhaust may be vented outside of the building, to another room, into a passage in the wall, a ventilation system or a specified chamber. In  FIG.  14 B  the vacuum  170  is downstream to pull air, water, bacteria, or other particles down and away from the user&#39;s hand(s) and into the wall  161 . The vacuums  170  are configured to remove the aerosols generated by hand drying. In addition or in the alternative, a blower or fan may be upstream of the chamber. Additional, different, or fewer components may be included. 
       FIGS.  15 A and  15 B  illustrate another embodiment of a hand dryer  172  having various vacuum positions. The embodiment of  FIGS.  15 A-B  includes dual ducts  173 . Each duct  173  corresponds to a different hand. The user&#39;s hands are placed into the ducts past the air knives (i.e., deeper into the ducts  173  than the air knives). The exhaust  174  provides a path for the air, water, and aerosols that are blown from the user hand(s) to escape through the bottom of the hand dryer  172 . The exhaust  174  may empty into a space below the floor. The exhaust  174  may connect to a ventilation system. In some examples, each of the ducts  173  is connected to a separate exhaust path. In some examples, the ducts  173  are combined (connected) into a single exhaust path. 
       FIG.  16    illustrates an example hand dryer  100  according to any of the embodiments herein mounted in association with a sink  180  including one or more faucets  181  and a drain  188  and/or in association with mirror  182 . The hand dryer  100  may be mounted above the sink  180  but still providing an open space  183  (e.g., for mopping, user&#39;s feet, a wheelchair, etc.). Additional, different, or fewer components may be included. 
     In one example, the operation of the hand dryer  100  is tied to the faucets  181 . For example, the faucets  181  may be actuated (e.g., turned on) through a proximity or motion sensor. The hand dryer  100  may be turned on after a predetermined time (e.g., 10 seconds, 20 seconds, 30 seconds). The predetermined time may be selected to encourage handwashing for that amount of time. 
     The faucets  181  dispense water that empties through drain  188 . The drain of the hand dryer (e.g., drain  115 ) may be fluidly coupled to the drain  188 . Thus, the water that drains from the sink  180  and the hand dryer  100  may be connected with a T or other coupling device behind or underneath the sink  180 . 
     In addition, the hand dryer  100  may be connected to an exhaust for the air through the wall behind the sink  180 . Thus, the hand dryer  100  includes a water drain and an air exhaust that may be located at least partially in the sink  180  and/or the supporting wall. 
       FIG.  17    illustrates a cutaway view of the example hand dryer  100  of  FIG.  16   .  FIG.  17    illustrates that the cyclones  102  and/or housing  189  are mounted between faucets  181  on the sink  180 . The air knives  101  may be mounted with the housing  189  so that only an opening is visible. The opening may be slanted down and inward into the hand drying duct of the housing  189 . 
       FIG.  18    illustrates multiple hand dryers  100  according to any of the embodiments herein integrated with a sink  180 . In this example a single housing may support or be coupled to both the sink  180  and the hand dryer  100 . The housing may also support the faucet  181  and a soap dispenser  184 . A leg or support  185  may provide support from the floor for the hand dryers  100  and the sink  180 . A mount  186  may support the housing including the sink  180  and the hand dryers through a connected with the wall. The mount  186  may be located between the wall and the housing supporting the sink  180 . Multiple sinks  180  may be mounted adjacent to one another. In some examples, each sink  180  is associated with a single-hand dryer  100  on each side. In some examples, adjacent sinks  180  share the single-hand dryer  100  between them. Additional, different, or fewer components may be included. 
       FIG.  19    illustrates multiple hand dryers  100  according to any of the embodiments herein integrated with a sink  180  and cabinet  190 . The air exhaust from the hand dryers  100  may pass through the cabinet  190  to give access for maintenance. Similarly, the water drain for the sink  180  and the hand dryer  100  may pass through the cabinet  190  to give access for maintenance. An electrical connection may be provided within the cabinet  190 . The electrical connection may provide power to an automatic valve of the faucet  181  and/or the fan of the hand dryers  100 . 
       FIG.  20    illustrates an example control system  301  for any of the dryer systems of  FIGS.  1 - 19   . The control system  400  may implement the controller  10  in other examples. The control system  400  may include a processor  300 , a memory  352 , and a communication interface  353  for interfacing with devices or to the internet and/or other networks  346 . In addition to the communication interface  353 , a sensor interface may be configured to receive data from the sensors described herein or data from any source described herein. The components of the control system  400  may communicate using bus  348 . The control system  400  may be connected to a workstation or another external device (e.g., control panel) and/or a database for receiving user inputs, system characteristics, and any of the values described herein. 
     The control system  400  may include a sensor  12  configured to generate sensor data for an object in vicinity to the sensor, and/or timer  11  configured to measure an elapsed time period. The processor  300  is configured to generate instructions to operate the hand dryer (e.g., turn on a fan) to move air through the at least one cyclone in response to the sensor data or the elapsed time period. 
     Optionally, the control system  400  may include an input device  355  and/or a sensing circuit in communication with any of the sensors. The sensing circuit receives sensor measurements from sensor  12  as described above. The input device  355  may include a switch (e.g., actuator), a touchscreen coupled to or integrated with, a keyboard, a remote, a microphone for voice inputs, a camera for gesture inputs, and/or another mechanism. 
     Optionally, the control system  400  may include a drive unit  340  for receiving and reading non-transitory computer media  341  having instructions  342 . Additional, different, or fewer components may be included. The processor  300  is configured to perform instructions  342  stored in memory  352  for executing the algorithms described herein. A display  350  may be supported by any of the components described herein. The display  350  may be combined with the user input device  355 . 
       FIG.  21    illustrates a flow chart for the control system  400  of  FIG.  19   . The acts of the flow chart may be performed by any combination of the control system  400 , the network device, or the server. Additional, different or fewer acts may be included. 
     At act S 101 , the processor  300  may receive sensor data from the sensor  12 . The sensor data is indicative of presence of an object in vicinity of the hand dryer  100 . The sensor  12  may detect the presence of one or more hands within a drying duct of the hand dryer  100 . The sensor data may indicate that a faucet has been used. The sensor data may indicate the presence of a user near the hand dryer  100 . 
     At act S 103 , the processor  300  generates a fan command in response to the sensor data. The fan command instructs a fan to operate or turn on (i.e., propel air) to an air knife. The air knife may provide a narrow path for the air that increases the velocity of the air and expels the air through at least one opening. At act S 105 , the flow of the air knife has an increased velocity and is directed to a user&#39;s hand where water (e.g., including particles or aerosols) is mechanically stripped from the hands into a ducted cavity towards at least one cyclone chamber. 
     At act S 107 , the air flow is subsequently directed to at least one cyclone chamber where it follows at least a partially circular path or circuitous path to project particles to a surface of the cyclone chamber. Some of the air exits the cyclone chamber through an exhaust path. At least some of the water exits the cyclone chamber through a drain. In some examples, a portion of the water may exit with the air through the exhaust path. 
     At act S 109 , the processor  300  generates a sanitization command in response to the sensor data to perform a sanitization, disinfection, or other cleaning action on the projected particles. The sanitation command may cause an ultraviolet line to irradiate the at least one cyclone chamber (e.g., including particles or aerosols adhered to the inner surface of the at least one cyclone chamber). The sanitation command may cause a misting generator to generate a mist including a chemical (e.g., hydrogen peroxide) in the at least one cyclone chamber. The sanitation command may cause an ozone generator to release ozone in the at least one cyclone chamber. Any combination of these disinfection techniques may be used. 
     Processor  300  may be a general purpose or specific purpose processor, an application specific integrated circuit (ASIC), one or more programmable logic controllers (PLCs), one or more field programmable gate arrays (FPGAs), a group of processing components, or other suitable processing components. Processor  300  is configured to execute computer code or instructions stored in memory  352  or received from other computer readable media (e.g., embedded flash memory, local hard disk storage, local ROM, network storage, a remote server, etc.). The processor  300  may be a single device or combinations of devices, such as associated with a network, distributed processing, or cloud computing. 
     Memory  352  may include one or more devices (e.g., memory units, memory devices, storage devices, etc.) for storing data and/or computer code for completing and/or facilitating the various processes described in the present disclosure. Memory  352  may include random access memory (RAM), read-only memory (ROM), hard drive storage, temporary storage, non-volatile memory, flash memory, optical memory, or any other suitable memory for storing software objects and/or computer instructions. Memory  352  may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described in the present disclosure. Memory  352  may be communicably connected to processor  300  via a processing circuit and may include computer code for executing (e.g., by processor  300 ) one or more processes described herein. For example, memory  298  may include graphics, web pages, HTML files, XML files, script code, shower configuration files, or other resources for use in generating graphical user interfaces for display and/or for use in interpreting user interface inputs to make command, control, or communication decisions. 
     In addition to ingress ports and egress ports, the communication interface  353  may include any operable connection. An operable connection may be one in which signals, physical communications, and/or logical communications may be sent and/or received. An operable connection may include a physical interface, an electrical interface, and/or a data interface. The communication interface  353  may be connected to a network. The network may include wired networks (e.g., Ethernet), wireless networks, or combinations thereof. The wireless network may be a cellular telephone network, an 802.11, 802.16, 802.20, or WiMax network, a Bluetooth pairing of devices, or a Bluetooth mesh network. Further, the network may be a public network, such as the Internet, a private network, such as an intranet, or combinations thereof, and may utilize a variety of networking protocols now available or later developed including, but not limited to TCP/IP based networking protocols. 
     While the computer-readable medium (e.g., memory  352 ) is shown to be a single medium, the term “computer-readable medium” includes a single medium or multiple media, such as a centralized or distributed database, and/or associated caches and servers that store one or more sets of instructions. The term “computer-readable medium” shall also include any medium that is capable of storing, encoding, or carrying a set of instructions for execution by a processor or that cause a computer system to perform any one or more of the methods or operations disclosed herein. 
     In a particular non-limiting, exemplary embodiment, the computer-readable medium can include a solid-state memory such as a memory card or other package that houses one or more non-volatile read-only memories. Further, the computer-readable medium can be a random access memory or other volatile re-writable memory. 
     Additionally, the computer-readable medium can include a magneto-optical or optical medium, such as a disk or tapes or other storage device to capture carrier wave signals such as a signal communicated over a transmission medium. A digital file attachment to an e-mail or other self-contained information archive or set of archives may be considered a distribution medium that is a tangible storage medium. Accordingly, the disclosure is considered to include any one or more of a computer-readable medium or a distribution medium and other equivalents and successor media, in which data or instructions may be stored. The computer-readable medium may be non-transitory, which includes all tangible computer-readable media. 
     In an alternative embodiment, dedicated hardware implementations, such as application specific integrated circuits, programmable logic arrays and other hardware devices, can be constructed to implement one or more of the methods described herein. Applications that may include the apparatus and systems of various embodiments can broadly include a variety of electronic and computer systems. One or more embodiments described herein may implement functions using two or more specific interconnected hardware modules or devices with related control and data signals that can be communicated between and through the modules, or as portions of an application-specific integrated circuit. Accordingly, the present system encompasses software, firmware, and hardware implementations. 
     The illustrations of the embodiments described herein are intended to provide a general understanding of the structure of the various embodiments. The illustrations are not intended to serve as a complete description of all of the elements and features of apparatus and systems that utilize the structures or methods described herein. Many other embodiments may be apparent to those of skill in the art upon reviewing the disclosure. Other embodiments may be utilized and derived from the disclosure, such that structural and logical substitutions and changes may be made without departing from the scope of the disclosure. Additionally, the illustrations are merely representational and may not be drawn to scale. Certain proportions within the illustrations may be exaggerated, while other proportions may be minimized. Accordingly, the disclosure and the figures are to be regarded as illustrative rather than restrictive. 
     While this specification contains many specifics, these should not be construed as limitations on the scope of the invention or of what may be claimed, but rather as descriptions of features specific to particular embodiments of the invention. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. 
     Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub-combination or variation of a sub-combination. 
     One or more embodiments of the disclosure may be referred to herein, individually and/or collectively, by the term “invention” merely for convenience and without intending to voluntarily limit the scope of this application to any particular invention or inventive concept. Moreover, although specific embodiments have been illustrated and described herein, it should be appreciated that any subsequent arrangement designed to achieve the same or similar purpose may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all subsequent adaptations or variations of various embodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those of skill in the art upon reviewing the description. 
     It is intended that the foregoing detailed description be regarded as illustrative rather than limiting and that it is understood that the following claims including all equivalents are intended to define the scope of the invention. The claims should not be read as limited to the described order or elements unless stated to that effect. Therefore, all embodiments that come within the scope and spirit of the following claims and equivalents thereto are claimed as the invention.