CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priority on United States Provisional Patent Application No. 61/353,851 filed June 1 1 , 2010, the entire content of which is incorporated herein by reference.

TECHNICAL FIELD

[0002] The present application relates to hand dryers and, more particularly, to hand dryers which can provide variable air flow.

BACKGROUND OF THE ART

[0003] Hand dryers typically use a stream of airflow in order to dry the hands of a user. Certain hand dryers are actuated using a button, while others are automatically actuated using, for example, a sensor which detects the presence of the user's hands. While in operation, following actuation, the hand dryers generally project a steady stream of airflow onto the user's hands. Therefore, a constant amount of airflow is ejected from the hand dryer during operation thereof. However, the airflow ejected from such hand dryers may sometimes be either too slow, too fast and/or too cold or hot for a user.

[0004] Certain prior art hand dryers project a stream of airflow at room-temperature, while others heat the air prior to projecting a stream of hot airflow. These hand dryers typically heat the air to a predetermined constant temperature using an electrical heating element. However, a user may sometimes find the airflow to be either too hot or not sufficiently hot.

[0005] Accordingly, users generally have different preferences in terms of the properties of the airflow with which they dry their hands. Moreover, if users find an airflow to be too hot or too forceful and thus choose to move their hands away from the automatic hand dryer in order to change how the air feels on their hands, the sensor of the hand dryer may be unable to detect the presence of their hands, which may lead to the hand dryer shutting down. In addition, certain users may find the hand dryer to be too loud for their personal taste. [0006] Therefore, improvements in the art of hand dryers remain desirable. SUMMARY OF THE INVENTION

[0007] In accordance with an aspect of the present invention, there is provided a hand dryer having an internal gas path at least partially defined between an air inlet through which air flows into the hand dryer and an outlet opening at a downstream end thereof through which air flows out of the hand dryer, comprising: a compressor driven by a motor for drawing air into the air inlet, compressing the air, and feeding the air to the outlet opening; and a variable-flow exhaust nozzle located at the downstream end of the hand dryer, the variable exhaust nozzle defining the outlet opening at an exit thereof, the variable exhaust nozzle being operable to vary the size of the outlet opening to control one or more properties of the airflow exiting the outlet opening.

[0008] There is also provided, in accordance with another aspect of the present invention, a method for operating a hand dryer, the method comprising: actuating a motor of the hand dryer when the user's hands are detected, the motor drawing air into the hand dryer and ejecting air therefrom; determining a distance separating the user's hands from the hand dryer; and modifying a size of an outlet opening of the hand dryer based on the determined distance separating the user's hands from the hand dryer, such as to modify at least one property of the air flowing therefrom.

[0009] There is also provided, in accordance with another aspect of the present invention, a hand dryer having a motor driven compressor which feeds air to an outlet opening of the hand dryer, comprising: one or more sensors disposed proximate said outlet opening of the hand dryer, the one or more sensors including at least one of a temperature sensor operable to measure a temperature of the airflow exiting the hand dryer via the outlet opening and to produce a signal representative of said measured temperature, and a proximity sensor operable to measure a distance between a user's hands and the sensor and to produce a signal representative of said measured distance; and a variable-flow exhaust nozzle defining the outlet opening at an exit thereof, the variable-flow exhaust nozzle being in communication with said at least one sensor for receiving the signal therefrom and being operable to vary the size of the outlet opening in order to control at least one property of the airflow exiting the hand dryer based on the signal from the sensor.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Fig. 1 is a front perspective view of the internal components of a hand dryer in accordance with an embodiment of the present application;

[0011] Fig. 2 is a rear perspective view of the hand dryer of Fig. 1 ;

[0012] Fig. 3 is a front perspective view of the hand dryer of Fig. 1 , shown with at least a first portion of an internal casing and a nozzle assembly removed for illustration purposes;

[0013] Fig. 4 is a perspective view of a second portion of the internal casing of the hand dryer of Fig. 1 ;

[0014] Fig. 5 is an enlarged perspective view of a downstream portion of the hand dryer of Fig. 1 , showing the airflow outlet and variable baffle;

[0015] Fig. 6 is a perspective view of an alternate embodiment of the hand dryer of Fig. 1 , with at least the first casing portion and the nozzle assembly removed for illustration purposes;

[0016] Fig. 7a is a lower side perspective view of an external casing of the present hand dryer, which encloses the internal components of the hand dryer shown in Fig. 1 ;

[0017] Fig. 7b is an upper side perspective view of the external casing of Fig. 7a;

[0018] Fig. 8 is a perspective view of the external casing of Fig. 7a, with the cover portion thereof removed;

[0019] Fig. 9a is a side elevational view of the external casing of Fig. 7a, shown in a first, partially recessed, mounting position; and

[0020] Fig. 9b is a side elevational view of the external casing of Fig. 7a, shown in a second, fully recessed, mounting position. DETAILED DESCRIPTION

[0021] Referring to Fig. 1 , the internal components of a hand dryer in accordance with a first embodiment of the present hand dryer is generally illustrated at 10. These internal components are received within an external casing 8, or dryer box, as will be described in further detail below with reference to Fig. 7. This assembly of the internal components will generally be described herein as the hand dryer 10, however it is to be understood that the fully assembled hand dryer which is mounted to the wall of a public restroom, for example, will include the internal components 10 as well as the external casing 8 within which they are received.

[0022] The internal assembly of the hand dryer 10 comprises an internal casing 12 which includes a first casing portion 14 and a second casing portion 16, the casing portions 14, 16 being connected together to define an internal cavity within which the systems of the dryer are housed, and also through which the airfoil is ejected, as will be seen.

[0023] The internal casing 12 includes, at an upstream casing end 12a thereof, a combined motor and air compressor device 20 for compressing and propelling the air. The casing 12 includes, at a downstream end 12b thereof, a variable exhaust nozzle 18 which controls the air being ejected from the hand dryer 10. An actuator 22 is operatively connected to the exhaust nozzle 18, or more particularly to the baffle 36 disposed therewithin, for controlling the size of an outlet opening 38 of the hand dryer 10. As will be described in further detail below with reference to Fig. 5, the actuator 22 is operatively connected to the baffle 36, so as to pivotally displace the baffle, i.e. open and close the baffle 36, in order to increase or decrease the size of the outlet opening 38 through which the heated air is forced upon ejection from the hand dryer via the exhaust nozzle 18. As such, the exhaust nozzle 18 is variable in size, such as to thereby vary at least one of the speed and/or pressure of the air ejected through the exhaust nozzle 18. In the embodiment shown, the baffle 36 within the exhaust nozzle 18 is hinged, such as to operate as a gate or door, which pivots to open or close the nozzle exit opening, and thereby is used for controlling the flow of air exiting the casing 12 through the outlet opening 38. As the baffle 36 of the exhaust nozzle 18 is opened or closed, the outlet opening 38 varies in size. [0024] In the embodiment shown, at least a portion of the motor and compressor device 20 is enclosed by the casing 12. As seen in Fig. 1 , the dryer assembly 10 includes an instrumentation system 24, which is connected to the casing 12 and includes at least one sensor and an electronics circuit board, including a memory chip and control system hardware, which operate and control the functioning of the present hand dryer in the manner which will be described below.

[0025] Referring to Fig. 2, the motor and compressor device 20 includes, at an upstream motor end 20a thereof, an inlet 23 for receiving air inside the hand dryer 10. In the embodiment shown, the inlet 23 is centrally located on the motor and compressor device 20, however, in another embodiment, the inlet 23 need not be centrally located and may, for example, be located peripherally.

[0026] As seen in Figs. 1 -2, the internal casing 12 includes pivots points 27 protruding on opposite sides of an outer surface 40 thereof, the pivot points 27 being located in proximity of the upstream casing end 12a. The pivots points 27 may be used to connect the hand dryer 10 to the dryer box or external casing 8 (see Fig. 7), which is mounted to the wall. Moreover, the hand dryer 10 may be pivoted about the pivot points 27 with respect to the dryer box, such that the exhaust nozzle 18 may be directed downwards, i.e. towards the ground, or horizontally, i.e. parallel to the ground, or alternatively, in any direction therebetween as well as upwards, as desired. The pivot points 27 therefore allow the hand dryer 10 to be mounted in a configuration which permits air flow to be directed in any one or more of a number of directions, as desired.

[0027] As seen in Fig. 3, the motor and compressor device 20 is shown positioned inside the second casing portion 16. The casing 12 defines a gas path 26 from the motor and compressor device 20 to the outlet opening 38. In the embodiment shown, the gas path 26 is formed between the first and second casing portions 14, 16, which provide a double curved, or S-shaped, gas path 26 through which the air flows. The double curved gas path 26 helps to align and smooth the airfoil which comes of the motor/compressor outlet, and therefore provides for a smooth airflow upon exit from the hand dryer 10.

[0028] The motor and compressor device 20 draws air therein through the air inlet 23, compresses the air and subsequently propels the air therefrom along the gas path 26 formed by the casing 12. The motor and compressor device 20 comprises a compressor portion 28 and a motor portion 30 which are located on a same common shaft 31. The motor portion 30 drives the compressor portion 28 which ingests air through the air inlet 23, and then compresses the air received therethrough. The compressed air is subsequently propelled around the motor portion 30 in order to cool the motor portion 30, and is then propelled from the motor and compressor device 20 into the gas path 26 formed within the internal casing. As such, the compressed air is at least partially preheated by the motor portion 30 prior to being expelled into the gas path 26, which enables the heating requirements of any additional heating element, if provided, located further downstream to be lower, thereby reducing energy consumption. Additionally, this configuration is also advantageous in that directing the compressed air past and/or around the motor acts to simultaneously cool the motor, due to the heat transfer from the motor to the compressed air.

[0029] As seen in Fig. 4, the second casing portion 16 includes a set of ribs 32 protruding from an inner surface 34 thereof. The ribs 32 are generally located between the compressor portion 28 and the motor portion 30, and are used to redirect or focus the air leaving the compressor portion 28 towards the motor portion 30 in order to increase heat transfer between the motor portion 30 and the air, i.e. to cool the motor portion 30 and also pre-heat the air, as well as to reduce the sound caused by the compressor portion 28. While the above-mentioned heat transfer which acts to cool the motor and pre-heat the compressed air remains possible even without these ribs 32, providing these ribs 32 has been found helpful to further improve the heat transfer from the motor to the compressed air.

[0030] Referring now to Fig. 5, wherein the operation of the variable flow exhaust nozzle 18 of the dryer assembly 10 will be described in further detail, the exhaust nozzle 18 is located at the downstream end of the casing 12 at an exit of the gas path 26, and is variable in size, such as to thereby vary at least one of the speed and/or pressure of the air ejected through the exhaust nozzle 18. In the embodiment shown, the exhaust nozzle 18 is defined by the baffle 36, which extends from the inner surface 34 of the second casing portion 16, the two lateral inside walls 37 of the casing 12, and the center wall 39 of the first casing portion 14. The exhaust nozzle 18 defines the outlet opening 38 at an utmost downstream end thereof. The outlet opening 38 acts as an outlet of the hand dryer 10, through which air is ejected. The baffle 36 is hinged on the inner surface 34 of the second casing portion 16 and as such, operates as a gate or door, which opens or closes, for controlling the flow of air exiting the casing 12 through the outlet opening 38. As the baffle 36 of the exhaust nozzle 18 is opened or closed, the outlet opening 38 varies in size.

[0031] The actuator 22 is operatively connected to the baffle 36, so as to displace the baffle, i.e. open and close the baffle 36, in order to increase or decrease the size of the outlet opening 38. The actuator 22 includes a housing 42 connected to the casing 12, and at least one arm 44 which is connected to the baffle 36 and which is displaceable relative to the housing 42. As such, the arm 44 may be linearly displaced, i.e. translated, so as to pivot the baffle 36, in order to vary the size of the outlet opening 38 of the exhaust nozzle 18. In another embodiment, the arm 44 need not be linearly displaced, but may alternatively be rotationally displaced, for example. While a pivoting baffle 36 is depicted, it is to be understood that an alternate baffle which acts in a different manner in order open and/or restrict the nozzle exit opening may also be used. For example, an iris type nozzle closing mechanism may be used, in another embodiment. Alternately still, a sliding gate-valve, ball vale or other type of valve closure mechanism can similarly be used to restrict the airflow as required. Provided that the nozzle closure mechanism permits partial opening at any number of a plurality of open positions (i.e. provided that the valve or nozzle restriction device is not simply a fully-open or fully-closed mechanism), any suitable airflow restricting valve device or baffle can be used.

[0032] By increasing or decreasing the size of the nozzle outlet opening 38, the size of the cross-sectional area through which the air exits the device is thus varied, and so, the velocity of the air passing through the exhaust nozzle 18 may be increased, or decreased. In addition, by restricting the size of the exhaust opening 18, i.e. throttling, a greater load is applied on the motor portion 30 of the motor and compressor device 20, due to the motor portion 30 having to use more energy to propel the air through a smaller exhaust opening 18. As such, the temperature of the motor portion 30 will tend to increase and the motor portion 30 transfers more heat to air flowing past it and/or around it. The air flow through the casing 12 will therefore have a greater temperature. Alternatively, by increasing the size of the exhaust opening 18, a smaller load is imposed on the motor portion 30 of the motor and compressor device 20, due to the motor portion 30 not requiring as much energy to propel the air through a larger opening. As such, the motor portion 30 has a lower temperature and transfers less heat to air passing thereby. The air flow through the casing 12 will therefore have a cooler temperature. As such, it is possible to control the exit temperature of the air propelled from the hand dryer 10 by controlling the area/size of the outlet opening 38 using the exhaust nozzle 18, which controls the load imposed on the motor portion 30.

[0033] The size of the outlet opening 38 is understood herein to mean the cross-sectional area of the outlet opening 38 through which air exits the hand dryer 10. As such, the size of the cross-sectional area may be increased or decreased by the exhaust nozzle 18.

[0034] In another embodiment, the actuator 22 need not be connected to the outer surface 40 of the casing 12, but may alternatively be connected to the inner surface 41 of the casing 12, or elsewhere which is appropriate given the configuration and shape of the assembly required in view of the desired size and/or shape of the surrounding external dryer casing.

[0035] The arm 44 of the actuator 22 may be displaced using various actuation means, such as for example, a motor, a solenoid, etc. In one embodiment, this actuation means may be located inside the housing 42 of the actuator 22. Although the actuator 22 is shown as attached to the second casing portion 16 of the casing 12, in other embodiments, the actuator 38 may be located on other parts of the casing 12. In other embodiments, the nozzle assembly may include various types of valves.

[0036] In the embodiment shown, as seen in Fig. 1 , the instrumentation system 24 is connected to the first casing portion 14 on an outer portion 52 thereof in proximity of the downstream end 12b. The instrumentation system 24 includes an electronics board 46 with a temperature sensor 48 and a proximity sensor 50 in electrical connected thereto. Referring to Fig. 5, the temperature sensor 48 and the proximity sensor 50 are shown with the electronics board 46 hidden from view. The temperature sensor 48 is located in proximity of the outlet opening 38, such that it can measure the temperature of the air passing through the outlet opening 38. [0037] Contrary to most known hand dryers, wherein a sensor is typically used only to detect the presence of a user's hands such as to turn the dryer on or off, the proximity sensor 50 of the present hand dryer 10 is operable not only to detect when a user's hands are in proximity of the dryer 10, but also to measure a distance separating the user's hands and the sensor on the hand dryer 10. The temperature and proximity sensors 48, 50 are connected to the exhaust nozzle 18, and may be used to send a signal to the actuator 22 in order to control the opening and closing of the baffle 36. As such, the proximity sensor 50 may be used to measure the distance between the user's hands and the hand dryer 10, and may, through the actuator 22, open or close the baffle 36, depending on the distance measured between the user's hands and the hand dryer 10. For example, if the proximity sensor 50 determines that a user has moved his/her hands away from the sensor 50, i.e. a greater distance separates the hand dryer 10 and the user's hands, the proximity sensor 50 may send a signal to the actuator 22 instructing the baffle 36 to be opened, in order to slow down the velocity of the air ejected from the hand dryer 10. Conversely, if the proximity sensor 50 determines that a user has moved his/her hands towards the sensor 50, i.e. a smaller distance separates the user's hands and the hand dryer 10, the proximity sensor 50 may send a signal to the actuator 22 instructing the baffle 36 to be further closed, in order to increase the velocity of the air ejected from the hand dryer 10. As such, simply by moving their hands toward or away from the dryer nozzle, a user may control the velocity of the air being ejected from the dryer. For example, if more drying is desired, the user may move his/her hands toward the dryer assembly, while if less drying action is desired, the user may move his/her hands away from the dryer assembly. This provides significantly more individual control for the user, in comparison with prior art devices which can only be switched on or off. Of course, once the proximity sensor 50 detects that a user's hands are in proximity thereof, the motor and compressor device 20 of the dryer is actuated in order to turn the dryer on.

[0038] In one embodiment, the proximity sensor 50 is a transmitter/receiver which is used to send a signal and to receive the same signal, or a corresponding signal, in return. As such, the delay between the time at which the signal is sent and the time at which the signal is received may be used to determine the relative distance separating the user's hands from the transmitter/receiver, i.e. from the casing 12. Different types of signals may be used by the transmitter/receiver, for example a radio signal, an infrared signal, etc. Note that in other embodiments, other types of proximity sensors 50 may be used instead of a transmitter/receiver. Moreover, the proximity sensor 50 may be used not only to detect a user's hands, but alternatively may be used to detect other items/members.

[0039] The hand dryer 10 may also, optionally, include at least one heating element inside the casing 12 for heating air flow passing therethrough. As seen in the embodiment shown in Fig. 6, the hand dryer 10 includes one or more heating elements 54, for example, with one heating element 54 being located inside the gas path 26 and another heating element 54 being located inside the motor and compression device 20. In other embodiments, the specific arrangement and location of the at least one heating element 54 inside the casing 12 may differ. In the embodiment shown, the heating elements 54 are configured as a grate which allows air to pass therethrough, i.e. they are porous. The heating elements 54 may be used to heat the air passing through the hand dryer 10, if hotter air is desired. Alternatively, if no additional heating is necessary, the heating elements 54 may simply allow air flow to pass therethrough without affecting the temperature thereof. In addition, the heating elements 54 may be used to automatically adjust for different voltage inputs to the hand dryer 10. As such, the hand dryer 10 may function with voltage inputs ranging from 100 to 250 volts AC.

[0040] In use, a user places his/her wet hands below the outlet opening 38 of the hand dryer 10. The proximity sensor 50 detects the presence of the hands and the motor portion 30 of the motor and compressor device 20 is actuated thereby. The compressor portion 28 ingests air into the casing 12 through the air inlet 23, compresses the air, and directs the air around the motor portion 30 which transfers heat to the air. The heated air is then propelled from the motor and compressor device 20 into the gas path 26. The heated air flows downstream through the gas path 26 until the heated air flows through the exhaust nozzle 18 and is propelled out of the casing 12 of the hand dryer 10 through the outlet opening 38 thereof. This heated air is propelled towards the user's hands and dries the user's wet hands by blowing water off the hands as well as by evaporating water thereon.

[0041] If the user desires to slow down the speed at which the heated air is propelled from the hand dryer 10 or to decrease the temperature of the heated air, the user may displace his/her hands away from the hand dryer 10. The proximity sensor 50 determines the greater distance separating the user's hands from the sensor 50 and sends a signal to the actuator 22. As per the received signal, the actuator 38 displaces the arm 44 so as to open the baffle 36 and so increases the size of the outlet opening 38. Therefore, a smaller load is imposed on the motor portion 30 and so less heat is transferred to the air passing through the casing 12. Moreover, the air does not accelerate as much as it passes through the larger outlet opening 38 and so the velocity of the air decreases. As such, air having a lower temperature and a lower velocity is propelled from the hand dryer 10 towards the hands of the user.

[0042] Alternatively, if the user desires to increase the speed of the heated air flowing from the hand dryer 10 or to increase the temperature thereof, the user may move his/her hands towards the hand dryer 10. The proximity sensor 50 detects the increased proximity of the user's hands and instructs the actuator 22 to displace the arm 44 so as to close the baffle 36 and thus decrease the size of the outlet opening 38. Therefore, a greater load is imposed on the motor portion 30 and so more heat is transferred to the air flowing through the casing 12. Moreover, the acceleration of the air is increased as it passes through the smaller outlet opening 38 and so the velocity of the air is increased. As such, air having a higher temperature and a greater velocity is propelled from the hand dryer 10 towards the hands of the user.

[0043] In another embodiment, the proximity sensor 50 may be electrically connected to the heating elements 54 and may increase or decrease the temperature generated thereby, depending on the particular distance separating the user's hands and the hand dryer 10. As such, in one embodiment, it may be possible to raise the velocity of the air propelled from the hand dryer 10 while simultaneously reducing the temperature thereof, and vice-versa, by controlling the exhaust nozzle 18 and the heating element 54.

[0044] It should be noted that the terms "close the baffle" or "open the baffle" do not necessarily refer to the complete opening or complete closure of the baffle 36 inside the gas path 26, but more specifically, refer to the direction in which the baffle 36 is displaced. The terms "open the baffle" and "close the baffle" respectively refer to the increased opening or increased closing of the baffle 36, such as in a door or a valve, i.e. to the increase or decrease in the area/size of the outlet opening 38. [0045] Different embodiments of the hand dryer 10 are possible. For example, in one embodiment, a controller unit, having a processor and related circuitry for example, of the instrumentation system 24 may be programmed such that a position of the baffle 36 of the exhaust nozzle 18 is associated with different distances separating a user's hands from the proximity sensor 50. Purely for example purposes, in one embodiment, if the proximity sensor 50 detects that a user's hands are fifty centimeters away, the baffle 36 is only closed halfway, whereas if the proximity sensor detects that a user's hands are twenty-five centimeters way, the baffle 36 is only one-quarter closed. In this embodiment, the size of the outlet opening 38 depends directly on the relative proximity of a user's hands with respect to the hand dryer 10. In another embodiment, once the proximity sensor 50 detects that a user's hands are in proximity thereof, the motor and compressor portion 20 is actuated and the baffle 36 is opened/closed to a predetermined position, regardless of the relative position of the user's hands with respect to the hand dryer 10. As the user displaces his/her hands towards or away from the hand dryer 10, the baffle 36 is subsequently controlled to open or close depending on the relative distancing of the user's hands from the hand dryer 10.

[0046] As mentioned, the temperature sensor 48 measures the temperature of the air flowing out of the exhaust nozzle 18. In one embodiment, if the temperature of the air exiting the exhaust nozzle 18 is determined by the controller of the instrumentation system 24 in communication with the temperature sensor 48 to be too hot for a user's hands, i.e. the temperature of the air is above a certain pre-determined limit, the temperature sensor 48 may send a signal to the actuator 22, instructing the actuator 22 to open the baffle 36, i.e. increase the size of the outlet opening 38. As such, a decreased load is imposed on the motor portion 30 and less heat is transferred therefrom to the air. Alternatively, in another embodiment, the temperature sensor 48 may be connected to the at least one heating element 54 and may decrease the amount of heat transferred from the heating element 54 to the air.

[0047] It is also possible to control the sound level of the hand dryer 10, by increasing or decreasing the velocity of the air propelled therefrom. As such, if a user desires to reduce the sound of the hand dryer 10, the user may displace his/her hands away from the hand dryer 10, thereby opening the variable nozzle 18, and so lower the velocity of the air propelled therefrom, which will reduce the sound level produce.

[0048] In the embodiment shown, the speed of the shaft 31 , i.e. of the motor and compressor device 20, is constant. However, in another embodiment, the speed of the motor and compressor device 20 may be variable and independently controlled, and may be used in conjunction with the variable exhaust nozzle 18 so as to further modify the properties of the air ejected from the hand dryer 10.

[0049] Referring now to Figs. 7a-9b, the external casing 8, or "dryer box", of the present hand dryer is depicted. As noted above, the internal components and sub-assembly 10 of the hand dryer are received within the external casing 8, which is then mounted to a wall of the room in which the dryer is to be installed. The external casing 8 of the present hand dryer is particular in that it is composed of several different modular components that fit together in a manner which simplifies mounting the entire dryer and which enables ready adjustment of the mounting position on and/or in the wall. More particularly, the external casing includes side walls 7 which are notched on their outer surfaces such as to define a number of parallel slots 6 formed in the side wall of the external casing 8. Two end plates 5 fit between the side walls 7 at the top and bottom ends thereof, such as to complete the outer periphery of the external casing. The lower one of the end plates 5 is disposed at the outlet end of the dryer, and therefore has a plurality of holes therein such as to permit the air flow from the dryer to exit. A cover 4 is removably engaged to the wall sub-assembly forming the periphery of the casing. A base plate 3 fits within the combined outer perimeter formed by the side walls 7 and the end plates 5, to which the internal components 10 of the dryer are mounted.

[0050] As seen in Figs. 7a-9b, an outer ring 3 extends about the full periphery of the wall sub-assembly, and defines a full-perimeter stop which abuts against a wall surface to which the hand dryer is to be mounted. As can be seen, this outer ring 3 fits within the parallel slots 6 formed in the side walls of the external casing, and its position can be adjusted as desired in order to recess at least a portion of the dryer (namely that portion disposed rearward of the outer ring 3 when disposed in position within one of the parallel slots 6) into the wall surface. As such, the external casing 8 of the present hand dryer is flexible in that it can be easily mounted in any number of positions, including a fully recessed position (whereby the outer ring 3 is disposed in a most forward slot 6 - as shown in Fig. 9b) and a less recessed position (whereby the outer ring 3 is disposed in a slot 6 located more rearward - as shown in Fig. 9a) such that the dryer protrudes further, if not fully, beyond the wall surface in a more traditional manner. Of course, any numbers of other recessed positions are also possible, from a near fully recessed low- profile position where only the cover 4 may protrude from the wall, to a near fully extended position, wherein a majority of the dryer body will extend outward from the wall surface. The relative position will dependent on the number of slots 6 provided and the relative position of the outer ring 3.

[0051] This configuration of the external casing 8 is particularly advantageous, as not only is the entire envelope and/or footprint of the presently described hand dryer very component/small, this ability to recess at least a portion of the present hand dryer into the wall cavity is very useful in many installations whereby space is a factor. Further still, the ability to readily adjust, on the fly at the time of installing the dryer, a desired distance into the wall cavity that the rear portion of the dryer casing is to be recessed is another very advantageous feature.

[0052] In tests conducted in order to compare the operation of the hand dryer of the present invention with known hand dryers commonly used in the marketplace, the present hand dryer was proven to draw less current (i.e. consume less electrical power), provide at least comparable - if not higher - air flow speed, provide significantly higher air volume (measured in CFM) than existing products on the market, and all this while being considerably smaller in overall size and much lighter in overall weight. See Table 1 , below, which sets out the results of these tests. These results are particularly desirable, especially considering the other above-noted features and/or advantages which the hand dryer of the present invention provides.

FLEX12 1200 10.0 21000.0 .75" x 1" 0.8 109.4 10.7 x 6 x 3 to 4.75 8

FLEX08 800 6.6 17000.0 .75" x 1" 0.8 94.4 10.7 x 6 x 3 to .75 8

Table 1

[0053] The above description is meant to be exemplary only, and one skilled in the art will recognize that changes may be made to the embodiments described without departing from the scope of the invention disclosed. For example, although the variable nozzle 18 is described as being a pivoting baffle 36 to open and close the outlet opening 38 of the nozzle, other nozzle configurations providing airflow modification and/or control are possible, such as a gate or ball valve, a camera shutter type closure, etc. Still other modifications which fall within the scope of the present invention will be apparent to those skilled in the art, in light of a review of this disclosure, and such modifications are intended to fall within the appended claims.