Abstract:
A personal light including a battery power source connected in series with a light-emitting diode (LED) light source and a switching mechanism configured for non-contact actuation are disposed within an environmentally sealed chamber. A reflector is employed to maximize reflection of light emanating from the LED and a lens having an anti-reflective coating thereon associated with the LED opposite the reflector to enhance the light output and magnify the narrow beam of the LED. The switch employs an actuation mechanism exterior to the chamber to activate and deactivate the light.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 11/246,449, pending, filed Oct. 6, 2005, which will issue as U.S. Pat. No. 7,364,319 on Apr. 29, 2008, which application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/616,910, filed Oct. 7, 2004, the disclosure of each of which application is incorporated herein in its entirety by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates generally to portable lights and, more specifically, to personal lights employing a non-contact switch actuating mechanism operable to control actuation of a light source powered by at least one battery, the light source and battery being completely physically isolated from an actuating portion of the switching mechanism in a sealed housing. 
       BRIEF SUMMARY OF THE INVENTION 
       [0003]    The present invention comprises a compact, battery-powered light, which may be of cuboidal configuration. The term “cuboidal,” as used herein, does not necessarily denote a perfect cube, but a three-dimensional shape generally defined by rectangular sides at mutually perpendicular angles. The size of the light may be optimized for a particular number and series of batteries, and to optimize yield in terms of material usage. Light is output from a face of the light rather than from an end, as in conventional, substantially tubular, battery-powered lights. 
         [0004]    In one embodiment, the light may be designed to function at a selected voltage through a current-limiting device connected in series with a battery power source, a light source comprising a light-emitting diode (LED) and a switch with a non-contact actuating mechanism. A suitable reflector may be employed to maximize reflection of light emanating from the LED, and a magnifying lens may be associated with the LED opposite the reflector to enhance the light output and magnify the narrow beam of the LED. A switch using a non-contact actuator, such as a Hall-effect-type magnetic reed switch, may be used to activate and deactivate the light, rather than a conventional, contact-type switch which is susceptible to wear and corrosion. At least the LED, battery and switch are environmentally isolated within a chamber in the light housing, the reed switch being responsive to the presence or absence of a magnetic field in close proximity thereto exterior to the chamber and provided by a movable element bearing at least one magnet. Thus, the light may be fabricated to exhibit a high water resistance, even under increased pressure, as well as being suitable for use in potentially explosive environments such as mines and certain manufacturing facilities wherein fumes or vapors may be highly susceptible to ignition from a spark associated with actuation of a conventional contact-type switch. 
         [0005]    A machine-angled edge may be provided at a back corner or along a juncture of a back surface and a bottom surface of the light to enable positioning thereof on a surface to present the light beam at an upward angle. A tapped hole may be provided on each of several surfaces of the light to enable mounting the light on a stand or tripod, attaching an accessory such as a belt clip or a carabiner clip to the light, or positioning the light on a helmet, head strap or body harness. A hole cross-drilled through the light body from one exterior surface to another thereof may be provided for attachment of a lanyard, which may be used for a wrist strap or a tie for a belt or strap. The lanyard may aid in the overall ergonomic shape of the light and it fits in the palm of a user&#39;s hand when carried by attachment to the wrist. 
         [0006]    The light size and shape may be optimized to provide comfort, portability and usefulness to the user due to its convenient size and shape format. For example, the size and shape may provide easy handling of the light in the palm of one&#39;s hand. All sharp edges and corners of the light may be chamfered to provide for a comfortable fit into the hand, reducing discomfort when the light is held for long periods and avoiding abrasion of the hand and other skin surfaces. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIGS. 1A through 1D  are exterior, perspective views of a battery-powered personal light of the present invention; 
           [0008]      FIG. 2  is a transverse, horizontal cross-section through the battery-powered personal light; 
           [0009]      FIG. 3  is a transverse, vertical cross-section through the battery-powered personal light, taken through the location of a non-contact switch thereof; 
           [0010]      FIG. 4  is an exterior, perspective view of the battery-powered personal light with a lid thereof removed; and 
           [0011]      FIG. 5  is a vertical cross-section through the center of the battery-powered personal light, from front to back thereof. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0012]    Referring to the drawing figures, the present invention comprises a battery-powered personal light  10  comprising a housing  12 , which may be of cuboidal configuration. Housing  12  is preferably formed from a single blank of relatively lightweight material, such as, for example, a metal or a resin. If formed of a metal, aluminum may be a suitable selection for the housing, as it is lightweight, easily machinable and offers good heat transfer properties, the desirability of the latter being apparent from the further discussion of the invention below. 
         [0013]    As depicted in  FIG. 2 , housing  12  may include twin circular battery bores  14  therein, offset toward exterior rear surface  16  of housing  12  for receiving two batteries. Battery bores  14  are laterally connected by aperture  18 , which may be milled through the material of housing  12  after battery bores  14  are formed. A larger, cylindrical lighting bore  20  may be formed in housing  12  transverse to battery bores  14  and centered on the face of the exterior front surface  22  of housing  12  through which aperture  18  is formed. Lighting bore  20  includes an elongated bore wall  24  terminating inwardly at a substantially flat bore base  26  and outwardly at stepped annular recesses  28 ,  30  and  32  of ever-greater inner and outer diameters. 
         [0014]    A light-emitting diode (LED)  34  mounted to a circuit board  36  and having a reflector  38  disposed thereabout and extending distally therefrom is disposed within lighting bore  20 . Reflector  38  may exhibit a parabolic profile or, alternatively, a dual angle parabolic/linear (in cross-section) profile. A current-limiting device  40  and a switch  42  configured for use with a non-contact actuating mechanism may be mounted to circuit board  36  to either side of LED  34 . This assembly is disposed within lighting bore  20  and aligned and secured therein by fasteners such as screws  44 , engaging threaded bores  46  (see  FIG. 3 ) formed through bore base  26 . 
         [0015]    LED  34  may be a high output (brightness) white LED such as a Luxeon® 1W LED (Lumileds Lighting, San Jose, Calif.) having relatively high efficiency for extended battery life. Nichia America Corporation, Mountville, Pa., also offers suitable high output (brightness) LEDs, as do other manufacturers. LEDs are very efficient compared to filament-type lamps, and offer high output and enhanced reliability, with operating lives approaching 100,000 hours. Reliability of such LEDs is enhanced by mounting to a heat-dissipative carrier, so circuit board  36  may be a thermally conductive circuit board with an aluminum back, for example, to act as a heat sink and transmit heat to (in this embodiment) the aluminum of housing  12 . If housing  12  is formed of a poor thermal conductor such as a resin, a heat sink plug (not shown) of suitable metal may be molded into the housing and placed in thermal contact with the LED through circuit board  36 . 
         [0016]    Reflector  38  may exhibit a mirror finish and an associated highly reflective coating, such as elemental aluminum, to optimize light output of LED  34 . There is also technology available from Fraen Corporation of Reading, Mass., for plastic injection molding of a reflector having a reflective surface as formed. 
         [0017]    An outer rim  48  of reflector  38  is received within stepped annular recess  28 . A lens  50  of greater diameter than that of outer rim  48  is disposed thereover, and the outer periphery of lens  50  is received within annular recess  30 , with a portion of lens  50  projecting outwardly therefrom (along the axis of reflector  38 ) into annular recess  32 . Lens  50  may comprise, for example, a sapphire lens, a mineral crystal lens or a polycarbonate lens. The lens  50  may be configured at least partially with an area of magnification to amplify light emanating from LED  34  and project it forward in the form of a focused beam, and the interior surface of lens  50  may be coated with an anti-reflective coating  52  to improve light transmission therethrough. 
         [0018]    An annular lens cap  54  with a threaded periphery  56  may be disposed within annular recess  32  and secured to internal threads  58  at the periphery of annular recess  32 . Lens cap  54  includes annular protrusion  60  along the periphery thereof, annular protrusion  60  having an inner edge  62  of slightly greater diameter than an outer diameter of lens  50  so as to extend over the outwardly projecting portion of lens  50  and center it within annular recess  30 . Annular foot  64  lies radially inward of annular protrusion  60  and is of lesser inward extent, so as to contact the outer face of lens  50  and gently and uniformly press lens  50  against the outer rim  48  to fix same in place against vibration, and to seat the periphery of lens  50  against the floor  66  of annular recess  32 . Elastomeric O-rings  51  and  65  may be respectively disposed in annular recess  49  of reflector rim  48  and annular recess  63  between annular protrusion  60  and annular foot  64  of lens cap  54  to provide a water- and vapor-tight seal for cylindrical lighting bore  20 , as the lens  50  is sandwiched between the O-rings  51  and  65 . Suitable materials for O-rings  51  and  65  include buna-N (nitrile) and fluorocarbon (such as Viton®) elastomers. As is evident from  FIG. 1A , lens cap  54  may include radially extending slots  68  in the exterior face  70  thereof, by which lens cap  54  may be rotated to move inwardly to press against lens  50  and be secured to housing  12 . Further, radially extending slots  68  provide outlets for light transmitted through lens  50  when LED  34  is powered and personal light  10  is placed, for example, on a flat surface with exterior front surface  22  face down. Finally, lens cap  54  provides a suitable surface for engraving of a product name, logo or other graphic as shown at  72 . 
         [0019]    Referring again to  FIG. 2 , a circular switch actuator bore  80  is formed in housing  12  parallel to circular battery bores  14  and to one side of lighting bore  20 . As may best be seen in  FIG. 3 , circular switch actuator bore  80  includes a first bore portion  82  of a first diameter and a second counterbore portion  84  of relatively greater diameter. A coil spring  86  of an inner diameter greater than that of first bore portion  82  and an outer diameter less than that of second counterbore portion  84  is disposed in second counterbore portion  84  and rests on annular floor  88  at the base of second counterbore portion  84 . Switch actuator rod  90  is disposed in switch actuator bore  80 , a first portion  92  thereof of lesser diameter being received in first bore portion  82  and a second portion  94  thereof of greater diameter being received in second counterbore portion  84 , coil spring  86  thus being received within a spring chamber  96  defined between housing  12  and switch actuator rod  90 . An end portion  98  of switch actuator rod  90  of lesser diameter than second portion  94  and having rounded end periphery  100  is located on switch actuator rod  90  opposite first portion  92 . Transverse spring bore  102  at the end of switch actuator rod  90  opposite end portion  98  has compressed coil spring  104  disposed therein (although, for example, an elastomer spring is also suitable), biasing detent ball  106  outwardly through ball retention aperture  108  coaxial with, but of smaller diameter than, transverse spring bore  102 , which is closed at its opposite end as, for example, by deforming or pruning the spring entry mouth of spring bore  102  after coil spring  104  is disposed therein. Detent ball  106  may be oriented in any circumferential direction, for example in a direction opposite that depicted in  FIG. 3 , or otherwise. Permanent magnets  112  and  114 , which may comprise (by way of example only) Neodymium, Samarium Cobalt, or AlNiCo magnets, are disposed within magnet chamber  116  formed within second portion of switch actuator rod  90  for use in actuation of switch  42 , as described below. As may be seen in  FIG. 3 , switch actuator rod  90 , which may be, for example, of brass, is formed in two parts each providing a cavity holding a permanent magnet  112  and  114 , respectively, the two parts joining along line  118  to form magnet chamber  116  and being held together by the magnetic fields of permanent magnets  112  and  114 . 
         [0020]    Referring again to  FIG. 2 , as well as to  FIGS. 3 ,  4  and  5 , it may be seen that one of the circular battery bores  14  includes a semicircular wiring chase  120  in the wall thereof, and running parallel thereto to the bottom  122  thereof, where lower battery contacts  124 , extending between circular battery bores  14  through aperture  18 , are disposed. Lower battery contacts  124  received in insulator tray  125  are laterally electrically connected at  126 , and electrically connected in series to LED  34 , current-limiting device  40  and switch  42  through wires  128  extending within wiring chase  120  and through feed ports  130  formed between circular battery bore  14  including semicircular wiring chase  120  and cylindrical lighting bore  20 . If desired, wire feed ports  130  may be sealed about wires  128  with, for example, silicone or an epoxy to seal off lighting bore  20  from the chamber created by battery bores  14  and aperture  18  therebetween. Wires  128  also extend within semicircular wiring chase  120  upwardly to electrically connect to upper battery contacts  132  which are carried in insulator tray  133  by lid  134 , when lid  134  is disposed over housing  12 . Both upper and lower battery contacts  132 ,  124  may be gold plated, for high reliability throughout the life of the battery to which they are connected. Further, spring contacts may be used at one end of each circular battery bore  14 , as known to those of ordinary skill in the art to maintain a resiliently biased, impact and vibration-proof connection with the batteries. Wires  128  may extend to upper battery contacts  132  so that lid  134  is physically connected to housing  12 , or may terminate at contacts (not shown) which align with resilient contacts (not shown) carried by lid  134  and electrically connected to upper battery contacts  132 , as known in the art. 
         [0021]    Lid  134  is configured to be self-aligning with housing  12  by engagement of front surface  136  thereof with rear wall  138  of ridge  140  extending across the front of the top of housing  12 . Further, substantially annular protrusion  142  on lid  134  is received into circular cutout  144  on the upper surface  146  of housing  12  which lies to the rear of ridge  140 , circular cutout  144  (which may extend partially into the rear wall  138 ) is coaxially aligned with second counterbore portion  84  of switch actuator bore  80 . Annular protrusion  142  includes switch actuator rod alignment bore  148  therethrough, which is only slightly larger than end portion  98  of switch actuator rod  90  and receives end portion  98  therein in a non-binding manner when lid  134  is disposed over housing  12 . Switch actuator rod alignment bore  148  may include dished or frustoconical mouth portion  149 , to better accommodate the digit of a user when pressing end portion  98  of switch actuator rod  90  to its greatest travel. Lid  134  may be affixed to upper surface  146  of housing  12  using fasteners such as screws  150 , which engage threaded fastener bores  152  flanking aperture  18 , the heads  154  of screws  150  being recessed in enlarged counterbores  156  in the top of lid  134 . 
         [0022]    To effect a water- and vapor-tight seal between lid  134  and housing  12 , a resilient gasket  158  as show in broken lines formed of a suitable elastomer of the same materials previously referenced herein for O-rings  61  and  65  may be partially received in groove  160  formed in the upper surface  146  of housing  12 , gasket  158  being compressed between lid  134  and housing  12  when screws  150  are made up in fastener bores  152 . Notably, after lid  134  is assembled with housing  12 , end portion  98  of switch actuator rod  90  does not protrude above upper surface  162  of lid  134  so that inadvertent contact therewith may be minimized. Semi-annular recess  164  defined between lid  134  and ridge  140  is of sufficient size to permit a digit of a user&#39;s hand, for example a thumb, to depress end portion  98  to activate personal light as described in more detail below. 
         [0023]    Current-limiting device  40  may comprise, for example, a resistor or a direct current-limiting regulator integrated circuit, as known in the art, the latter being typically more efficient than the former and providing extended life for LED  34 . Further, a current boost circuit as known in the art may also be connected in series with the other components, to provide greater flexibility in battery selection. 
         [0024]    Switch  42  may comprise a Hall-type magnetic reed switch or other switch susceptible to actuation using the presence or absence of an adjacent magnetic field. 
         [0025]    Batteries  170  which are received in circular battery bores  14  may comprise, by way of example only, commercially available 3V CR123 batteries. The type or number of batteries employed is not critical to practice of the invention. As batteries  170  are connected in series, a 6V power supply may be provided for LED  34 . It is specifically contemplated that rechargeable batteries may be employed with personal light  10  and, if so, that an inductively couplable charging mechanism  172  may be disposed, for example, on the underside of lid  134  and wires extended therefrom to batteries  170  may be employed to eliminate the need for opening lid  134  and removing batteries  170  for recharging, thus avoiding any potential for compromising the integrity of resilient gasket  158  over time due to normal wear and tear. To recharge, a charger (not shown) may be placed over personal light  10 , or personal light  10  placed in a charger configured with a cradle to receive personal light  10  and align inductively couplable charging mechanism  172  adjacent an inductive charging element of the charger. 
         [0026]    Referring again to  FIGS. 1 ,  2  and  4 , housing  12  of personal light  10  may include additional features to enhance the utility of the device. For example, threaded accessory bores  180  and  182  may be provided, respectively, in a side surface and a rear surface of housing  12 , as well as in a bottom surface thereof (not shown), if desired. Thus, for example, personal light  10  may be used with a belt clip or a carabiner clip (not shown) having a threaded fastener for insertion into an accessory bore  180  or  182 , or personal light  10  may be secured to a helmet, a climbing or rescue harness, or a head band or strap using a threaded fastener received in an accessory bore  180  or  182 . Similarly, use of a threaded accessory bore in the bottom surface of personal light  10  may enable mounting of personal light  10  to a tripod, staff or other stand. Further, lanyard bore  184  extends obliquely between a top surface of ridge  140  and a side surface of housing  12 , as best shown in  FIG. 4 . Thus, a lanyard, or a length of line or cable, may be used to hang personal light  10  or secure it to the person of a user or to another object. In addition, as may be seen in  FIGS. 1A ,  1 C,  1 D,  4 , and  5 , a chamfer  186  may be cut along the intersection of the rear exterior surface and bottom exterior surface so that personal light  10  may be rested on a flat surface and tilted upwardly at an angle. Chamfer  186  may lie at an angle approaching 45°, the precise angle depending upon the center of gravity of the complete assembly of the personal light  10  containing batteries  170 . Of course, a chamfer may be cut at the intersection of three adjoining exterior surfaces of housing  12  and used to orient personal light  10  at an additional, different angle. 
         [0027]    As noted above, the light size and shape may be optimized to provide comfort, portability and usefulness to the user due to its convenient size and shape format. For example, the size and shape may provide easy handling of the light in the palm of one&#39;s hand. Some or all edges and corners of the light may be chamfered or rounded (radiused) to provide for a comfortable fit into the hand, reducing discomfort when the light is held for long periods and avoiding abrasion of the hand and other skin surfaces. Further, several or all of the exterior surfaces of housing  12  and lid  134  may exhibit a surface treating such as knurling, or a heavy satin finish, to facilitate gripping by a user&#39;s hand. 
         [0028]    In use, personal light  10  may be activated and deactivated by manipulation of switch actuator rod  90  by the hand of a user. More specifically and by way of example only, the thumb of a user having personal light  10  cradled in the palm of his or her hand may be used to depress end portion  98  of switch actuator rod  90  to place permanent magnets  112  and  114  in lateral proximity to switch  42  to cause, in the case of a Hall-effect-type reed switch, the reed contacts to close and complete an electrical circuit to cause batteries  170  to deliver power to LED  34 . Upon depression of end portion  98  to a slight degree against the bias of coil spring  86  (which prevents inadvertent actuation of personal light  10 ), permanent magnets  112  and  114  are placed in proximity to switch  42  to cause power to flow to LED  34  as switch  42  closes, and release of end portion  98  will cause switch actuator rod  90  to move upwardly and switch  42  to open. However, if end portion  98  is depressed further, the first portion  92  of switch actuator rod  90  will protrude through the bottom surface of housing  12  and resiliently biased detent ball  106  will extend outwardly (see  FIG. 1D , wherein biased detent ball  106  has been rotated from the position shown in  FIGS. 2 and 3  for clarity and to illustrate that detent ball  106  carried by switch actuator rod  90  may be circumferentially oriented as desired), locking switch actuator rod  90  in place to maintain personal light  10  in an activated mode. 
         [0029]    While the present invention has been described in the context of a specific, illustrated embodiment, additions and deletions to, and modifications of, the illustrated embodiment will be readily apparent to those of ordinary skill in the art and are encompassed by the present invention, the scope of which is only limited by the claims which follow.