Abstract:
A headlamp includes a base having a front face defining a first imaginary plane along the front face and a first imaginary line orthogonal to the first plane. A light assembly is rotatably secured about the front face to the base. The light assembly includes a bezel having a rear surface defining a second imaginary plane along the rear surface and a second imaginary line orthogonal to the second plane so that the intersection of the first line and the second line defines a rotation angle that varies with the rotation of the light assembly relative to the base, thereby changing the attitude of the headlamp light assembly.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention generally relates to headlamps and, more particularly, to headlamps having a movable mount for attitude adjustment of a light beam emanating therefrom.  
         BACKGROUND OF THE INVENTION  
         [0002]    Headlamps, whether attached directly to the head of a user or integrated into protective headgear, are useful operating under low ambient light conditions. This is especially true during prolonged activities that require unfettered use of the hands of a headlamp wearer. Additionally, depending on the activities of a wearer, it is often advantageous to be able to adjust the attitude of the headlamp to selectively light an area about the wearer. A wearer might include a motorcyclist, a bicyclist, a firefighter, a miner, a construction worker, a hiker, a farm worker, a hunter or a naturalist.  
           [0003]    Prior art attempts to provide an adjustable attitude headlamp have resorted to a diametric pivot joint to adjust the angle of the light source relative to the headgear and/or the head of the wearer. A diametric pivot represents the weakest portion of the headlamp construction if exposed. Alternatively, a cumbersome support housing is built around the pivot to support and encompass the same thereby adding to the profile and weight of the lamp. Thus, there exists a need for a more rugged attitude adjustable headlamp.  
         SUMMARY OF THE INVENTION  
         [0004]    A headlamp includes a hollow base having a front face defining a first imaginary plane along the front face and a first imaginary line orthogonal to the first plane. A light assembly is rotatably secured to the base. The light assembly includes a bezel having a rear surface defining a second imaginary plane along the rear surface and a second imaginary line orthogonal to the second plane so that the intersection of the first line and the second line defines a rotation angle. The light assembly also includes a battery case attached to the bezel to create an enclosed volume therebetween. A battery and light source are located within the enclosed volume. A switch is provided to selectively form an electrical circuit between the light source and the battery. Rotation of the light assembly about the member connected to the base and the light assembly changes the rotation angle. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]    [0005]FIG. 1A is a perspective view of an inventive headlamp configured to have a 180° canting angle between the light assembly and base;  
         [0006]    [0006]FIG. 1B is a perspective view of the headlamp depicted in FIG. 1A configured to have a canting angle of about 150° between the light assembly canted and the base;  
         [0007]    [0007]FIG. 2 is an exploded view of the inventive embodiment depicted in FIG. 1A; and  
         [0008]    [0008]FIG. 3 is a perspective exploded partial cutaway view depicting the various planes and lines that define a canting angle in the inventive embodiment depicted in FIG. 1A. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0009]    The present invention has utility as lamp mountable to the head of a wearer or incorporated into headgear. The present invention provides a rugged and compact headlamp where the lighting assembly cants relative to a static base. The front face of a headlamp base and the rear surface of a bezel incorporated into the light assembly are complementary bevel cut features such that rotation of the bevel cut rear surface of the bezel relative to the base changes the attitude of the light assembly. The present invention details a novel canted headlamp and process for canting a light assembly relative to a static base to adjust light projection attitude.  
         [0010]    Referring now to FIGS.  1 - 3 , an inventive headlamp is shown generally at  10 . A base  12  is adapted to secure to the head of a wearer by way of a strap  14 . The base having conventional strap engaging fixtures such as posts or, as depicted in the figures, opposing blind holes  16  adapted to receive a spring-loaded hinge pin (not shown) affixed to the strap  14 . In the preferred embodiment, the base  12  is hollow and capable of receiving some other portion of the inventive headlamp therein. While the present invention is detailed with respect to a headlamp that is directly mounted to the head of a wearer by way of a headband, it is appreciated that a canted headlamp as detailed herein is readily incorporated into a helmet or other headgear. The base  12  has a basal face  20  adapted to contact the head of a wearer or engage a helmet or other headgear. Preferably, a skin compatible foam material  22  is intermediate between the basal face  20  and the skin of a wearer in those embodiments of the present invention, such as those depicted in FIGS.  1 - 3 , where the headlamp is secured directly to the head of a wearer. As shown in FIG. 3, the base  12  has a front face  24  that defines a first plane P 1  angled relative to the basal face  20 . A basal face is defined by a plane that contains the maximal number of points on the basal face  20 . An angle α is defined as the deviation of the front face angle relative to a normal line A to the basal face  20 . The front face  24  defines a first plane P 1 . A normal line N 1  to the plane P 1  extends therefrom.  
         [0011]    A light assembly shown generally at  40  in FIG. 2 rotates relative to the front face  24  of the base  12  such that the light assembly cants with rotation relative to the base  12 . The light assembly has a bezel  42  that has a rear surface  44 . The rear surface  44  defines a second plane P 2  that has a normal line N 2  thereto as shown in FIG. 3. The intersection of normal line N 1  to the first plane P 1  with the normal line N 2  to the second plane P 2  defines a canting angle β. The canting angle β being 180° where the front surface  52  of the bezel  42  is substantially parallel to the basal face  20  of the base  12 . Rotation of the bezel  42  relative to the base  12  varies the canting angle β away from 180°. Typically, the canting angle varies between 130° and 230°. Preferably, the canting angle is between 165° and 195°.  
         [0012]    The light assembly  40  has a battery case  50  attached to the bezel  42 . The battery case preferably having a circumferential flange  51  that is adapted to rotationally seat in contact with the front face  24 . An enclosed volume  18  is defined between the bezel  42  and the battery case  50 . A battery  52  and at least a portion of a light source  54  are located within the volume  18 . In a preferred embodiment, the light source  54  is a light emitting diode (LED). More preferably, the light source  54  is a plurality of light emitting diodes. It is appreciated that a light emitting diode operative herein has an emission perceptible to the human eye in a variety of colors illustratively including red, orange, yellow, green, blue, and white.  
         [0013]    A battery operative in the present invention is chosen such that alone or in a circuit with other batteries is sufficient to drive light emissions from the light source. Batteries operative herein include cylindrical batteries such as AAA, AA, A, metal hydride and lithium containing batteries; cuboidal batteries such as an alkaline 9-volt; and button-type batteries such as lithium containing batteries. Preferably, a button type battery is used. It is appreciated that to drive certain light sources a series circuit of batteries is utilized.  
         [0014]    The bezel  42  and base  12  are each independently formed of materials conventional to the art. Preferably, each is formed of an injection moldable thermoplastic material, although it is appreciated that the same are also formable from metals such as aluminum, brass, titanium, and steel. More preferably, the bezel rear surface  44  and front face  24  of the base  12  have comparable hardness values so as to slow wear at the interface therebetween.  
         [0015]    An electrical switch  60  upon activation forms an electrical circuit between the light source  54  and the battery  52 . The battery case  50  being in electrical contact with one pole  53  of the battery  52  and thereby with the switch  60  upon securement of the battery case  50  to the bezel  42 . The opposing battery pole  63  is in electrical contact with a circuit board  66  to which the light source  54  is secured. The switch  60  selectively creates a circuit between the light source  54  and the battery  52  upon engagement. Preferably, a reflector  68  having a light reflective outer surface  70  encompasses at least a portion of the light source  54 . A jewel  72  is optionally provided in the illumination light path of an inventive headlamp  10  to create internal reflections therein and thereby create a more uniform illumination field. A crystal  74  is optionally seated within the bezel  42  and serves to protect light assembly internal components from environmental contaminants. In an alternative embodiment, a switch underlies the crystal such that depressing the crystal relative to the base selectively forms an illumination producing circuit. The details of such a switch are found, for example, in U.S. Pat. No. 4,336,574, which is incorporated herein by reference. Preferably, access to light assembly internal components is by way of a threaded cap  78  engaging the rear face  80  of the battery case  50 .  
         [0016]    The light assembly  40  rotates relative to the base  12  through the use of conventional structures allowing rotation. The inventive embodiment depicted in FIG. 2 shows a circumferential race  84  that allows the flange  51  of the battery case  50  to rotate relative to the base  12 , it is appreciated that other structures such as an axial pivot pin rotatably interconnecting a light assembly and a base are also operative herein. An axial pivot pin is shown in a canting arrangement in, for example, U.S. Pat. No. 5,590,416 which is incorporated herein by reference.  
         [0017]    The drawings and specification collectively disclose a typical preferred embodiment of the invention. There is no intent to limit the invention by such disclosure, but rather to encompass modifications and alternate constructions apparent to one skilled in the art upon reading of the specification. The scope of the invention is intended to be defined by the appended claims.