Abstract:
Using a control system for automatically switching power between a first light source attached to a welding shield pivotally mounted to an adjustable headband, and a second light source attached to the headband, a method for alternating power to the light sources includes steps (a) raising the shield to the uppermost rotational position resulting in power on to the second light source, the second light source remaining on at the raised position, and (b) lowering the welding shield to the maximum allowable distance resulting in power off to the second light source immediately followed by power on to the first light source, the first light source remaining on at the lowered position.

Description:
CROSS-REFERENCE TO RELATED DOCUMENTS 
       [0001]    The present invention is a Divisional application from U.S. application Ser. No. 12/925,832, filed Oct. 30, 2010 and claims priority to a U.S. provisional patent application Ser. No. 61/280,382 entitled SAFTY HELMET WITH LIGHTING SYSTEM filed on Nov. 3, 2009 disclosure of which is incorporated herein in its entirety at least by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention is in the field of safety gear including workplace utility helmets and pertains particularly to methods and apparatus for controlling a lighting system adapted for a utility helmet. 
         [0004]    2. Discussion of the State of the Art 
         [0005]    In many industries like manufacturing and construction, welding is a common practice. Welders wear welding helmets, sometimes referred to as welding shields or face shields, during the course of their work. Generally speaking, a welding shield is constructed to pivot about the workers head and typically has two positions. One position is with the shield down during actual welding to protect the workers eyes and face from extreme light from the welding arc and from any debris that could be dislodged during the process. Periodically, the worker must raise the shield so the worker can see the workspace for weld preparation, cleaning, and other tasks performed during the course of welding. 
         [0006]    One challenge with welding using so-called welding helmets or shields, is that many workspaces where welding occurs are not sufficiently illuminated. Therefore, extra work must be undertaken to set-up lighting for these areas. The shield lens of a welding shield is typically colored or darkened like sunglasses in order to protect a worker&#39;s eye from extreme light flashing that occurs during the process of active arc welding. These lenses are to dark for the user to see the workspace without the light from active welding contributing to errors in the process resulting in poor quality. Self-darkening lenses for welding shields are available that darken only when extreme light is present. However, insufficient lighting still contributes to workspace errors during welding when the shield is lowered and when the shield is raised. 
         [0007]    Therefore, what is clearly needed is a lighting system for a utility helmet such as a welding shield and method for controlling that system for the purpose of illuminating the workspace in a focused manner depending upon shield position. 
       SUMMARY OF THE INVENTION 
       [0008]    Using a control system for automatically switching power between a first light source attached to a welding shield pivotally mounted to an adjustable headband, and a second light source attached to the headband, a method is provided for alternating power to the light sources comprising the steps (a) raising the shield to the uppermost rotational position resulting in power on to the second light source, the second light source remaining on at the raised position, and (b) lowering the welding shield to the maximum allowable distance resulting in power off to the second light source immediately followed by power on to the first light source, the first light source remaining on at the lowered position. 
         [0009]    In one aspect, in step (a), at the uppermost rotational position of the shield relative to the headband, one of two magnets strategically mounted to the interior surface of the welding shield is aligned over a magnetic positional switch strategically mounted to the headband. In a variation of this aspect, in step (b), at the lowermost rotational position of the shield relative to the headband, the other of the two magnets strategically mounted to the interior surface of the welding shield is aligned over the magnetic positional switch strategically mounted to the headband. 
         [0010]    In one aspect of the method the light sources are light emitting diodes. In one aspect a manual rotational switch overrides an automatic control system. In a variation of this aspect the manual rotational switch includes an off position and three on positions, one for the first light source, one for the second light source, and one for deferring operation to the automatic control system. In one aspect one or both light sources are LEDs of differing colors. In a variation of this aspect, the differing colors are a bright white light and a softer yellow light. 
         [0000]    9. The method of claim  1  wherein one or both light sources have an adjustable focus capability to emit a more focused and narrow beam or a wider and less focused beam according to need.
 
10. The method of claim  1  wherein one or both light sources are directionally adjustable.
 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
         [0011]      FIG. 1  is a perspective view of a welding shield  60  according to an embodiment of the present invention. 
           [0012]      FIG. 2  is a perspective view of the shield of  FIG. 1  with a shield lens open revealing a second transparent lens.  FIG. 3  is a side view of the shield of  FIG. 1  illustrating a manual lighting system control switch with an off and an auto setting. 
           [0013]      FIG. 4  is a perspective view of a headband lighting system leveraging a magnetic reed switch for powering on a mounted light source according to an embodiment of the present invention. 
           [0014]      FIG. 5  is a perspective view of a headband lighting system leveraging a battery and having a connector to a shield lighting system. 
           [0015]      FIG. 6  is a cable lighting system for retrofitting to a welding shield according to an embodiment of the present invention. 
           [0016]      FIG. 7  is a cable lighting system for retrofitting to a welding shield headband according to an embodiment of the present invention. 
           [0017]      FIG. 8  is a side view of the welding shield of  FIG. 1  adapted with a positional switching system, the shield raised to power on the headband light source. 
           [0018]      FIG. 9  is a side view of the welding shield of  FIG. 1  adapted with a positional switching system, the shield lowered to power on the welding shield light source. 
           [0019]      FIG. 10  is a circuitry diagram illustrating a manual lighting control circuit with an automatic positional sensing switch setting. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    The inventor provides a unique welding shield with integrated lighting and lighting control system. The present invention will be described in enabling detail using the following examples, which may describe more than one relevant embodiment falling within the spirit and scope of the present invention. 
         [0021]      FIG. 1  is a perspective view of a welding shield  60  according to an embodiment of the present invention. Welding shield  60  may also be referred to herein as a face shield or helmet-face shield without departing from the spirit and scope of the present invention. The term welding shield is a well-known industry term for a welding helmet. 
         [0022]    In this example, shield  60  includes a welding shield lens  61  attached to shield  60  by way of one or more hinges  65 . Shield lens  61  may be an auto-darkening lens, a shaded lens, or a transparent protective viewing lens without departing from the spirit and scope of the present invention. Shield lens  61  is in the closed position. Lens  61  includes user operable tabs  66  to facilitate easy opening of the lens. 
         [0023]    Welding shield  60  is pivotally mounted to an adjustable headband  64  by frictional locking knobs  63 . A user places the headband over the head and adjusts the position of welding shield  60 , typically raising or lowering the shield using locking knobs  63  to lock the adjusted opposition. In one embodiment of the present invention, shield lens  61  may include solar cells  52  mounted thereon and adapted to enable charging of the lighting system of the welding shield. 
         [0024]    Welding shield  60  includes a light emitter  10 . Light emitter or light source  10  may be a light emitting diode (LED)  10  mounted on the front area of welding shield  60 . Light source  10  may be physically integrated into the surface wall of welding shield  60  or it may be treaded thereon, snapped thereon, glued thereon or affixed thereon using some other attachment method. Light source  10  may be adjustable in one embodiment to output a stronger more focused light beam or a wider less focused light beam. Welding shield  60  may be molded of a durable polymer material or composite material. Hinges  65  may be frictionally controlled to help secure welding shield lens  61  in an upright position. Light emitter  10  may be encapsulated in a high strength plastic, composite material, or other materials. Light source  10  is mounted on the outer face of welding shield  60  in an area that enables optimum illumination of a desired workspace area. 
         [0025]      FIG. 2  is a perspective view of welding shield  60  of  FIG. 1  shield lens  61  open revealing a second transparent lens. Welding shield  60  includes a second transparent viewing lens  62  that provides protective viewing option with the darker lens removed or raised. Lenses  61  and  62  may be manufactured of a resilient and shatter-resistant polymer material suitable for safety lens manufacture. In one embodiment lens  62  is removable from welding shield  60 . With welding shield  60  in the lowered position, light emitter  10  may be powered on automatically to provide illumination for the operator viewing the area through the darkened lens or through the secondary transparent lens  62 . 
         [0026]      FIG. 3  is a side view of welding shield  60  of  FIG. 1  illustrating a manual lighting system control switch with an off setting and an auto setting. Welding shield  60  has an integrated lighting system of which light source  10  is part of as described further above. Headband  64  has a headband light source  20  fixed thereto. Light source  20  may be an LED in one embodiment. In one embodiment, light source  20  has a focusing capability and can be adjusted to throw a more focused and narrow beam or a wider and less focused beam according to need. In one embodiment light sources  10  and  20  are directionally adjustable to a degree. 
         [0027]    Welding shield  60  may be raised or lowered about pivot positions created by frictional locking knobs  63  (one illustrated). Headband  64  provides an electrical communication pathway for laying the wire needed for integrating the two lighting control system available for the welding shield. Headband  64  may be manufactured from a durable but flexible polymer composite or material. A portion of welding shield  60  is removed in this example to permit view of lighting source  20 . 
         [0028]    Welding shield  60  includes a manual control dial  30  adapted for controlling the integrated lighting system of both the welding shield and the headband. In this example, dial  30  is a rotational dial having at least four settings that are selectable by an operator. One setting is off, selection thereof causing both lighting source  20  and lighting source  10  to be powered off. A next setting may be a setting, which causes power to be delivered to the welding shield external lighting source  10 . 
         [0029]    Welding shield  60  is lowered into a position for welding and darkened shield lens  61  is closed. In this position it is desirable that lighting source  10  is powered on. A third setting may cause power to be delivered to the headband lighting source  20 . Lighting source  20  would be powered on when welding shield  60  is raised to an elevated position thus exposing the headband lighting source to the workspace area. The fourth setting for rotary dial  30  is automatic or auto. Automatic or auto causes diversion from manual lighting control to automatic lighting control. Auto mode is operated in a preferred embodiment by raising and lowering the welding shield about its pivot points or frictional knobs  63 . More detail about operating auto mode to alternately illuminate the described lighting sources will be provided later in this specification. 
         [0030]      FIG. 4  is a perspective view of a headband lighting system leveraging a magnetic reed switch  44  for powering on a mounted light source according to an embodiment of the present invention. Switch  44  may comprise a magnetically operated switch for powering on headband lighting source  20  illustrated on the front portion of headband  64 . Locking knobs  63  are illustrated in this example. Lighting source  20  may be adjustable in direction, focus, and power without departing from the spirit and scope of the present invention. Light source  20  communicates with switch  44  via an electrical wiring  53 . In this example, a positional magnet on the inside of welding shield  60  passes over switch  44  when the welding shield is raised sufficiently causing the headband light  20  to power on. 
         [0031]      FIG. 5  is a perspective view of a headband lighting system leveraging a battery and having a connector to a shield lighting system. Headband  64  supports headband lighting source  20 . Lighting source  20  is connected to a battery  51  by wiring  53 . Battery  51  may be a rechargeable battery that can be charged electronically or by solar power. There may be more than one battery for supplying power to the integrated lighting system of the welding shield without departing from the spirit and scope of the present invention. 
         [0032]    In this example, wiring  53  includes an extendable plug  54  for connecting to the portion of the lighting system that is used to power on light emitter  10  described previously in this specification. Wiring  53  may be standard power electrical wiring of a gage suitable for illuminating emitters  10  and  20 . In one embodiment, lighting source  20  fixed to headband  64  includes LEDs of differing colors like bright white light and yellow “soft” light. 
         [0033]      FIG. 6  is a cable lighting system  70  for retrofit to a welding shield according to an embodiment of the present invention. In one embodiment of the present invention a stock-welding shield is retrofitted with a cable lighting system  70 . Lighting system  70  includes a connector plug  54  analogous to the connector plug of  FIG. 5  above. Wiring  53  includes wiring from plug  54  to a mountable manual control dial  30 , analogous to control dial  30  of  FIG. 3  above. Wiring  53  continues on one path to welding shield light emitter  10  and positional sensor switch  44  for automatic operation. Wiring  53  continues from dial  30  on another path to solar cell array  52 . The components of  FIG. 6  are adapted to be retrofit to a stock welding helmet or shield. 
         [0034]      FIG. 7  is a cable lighting system  71  for retrofit to a welding shield headband according to an embodiment of the present invention. Light emitter  20  has connection via wiring  53  to positional sensor  44 , which would mount to a headband of a welding shield. At the other end of light emitter  20  is battery  51 . Plug  54  enables connection to the other system  70 . The components of  FIG. 7  are adapted to retrofit to a stock welding shield headband. 
         [0035]      FIG. 8  is a side view of welding shield  60  of  FIG. 1  adapted with a positional switching system, the shield raised to power on the headband light source. Welding shield  60  is illustrated in a raised position relative to headband  64  exposing headband light source  20  to illuminate the workspace. A positional switch or magnetic reed switch  44  fixed to headband  64  is in alignment beneath one of magnets  42  mounted on positional sensor  41  that is mounted to the interior surface of the welding shield. Positional sensor  41  is mounted strategically in the arcurate path of rotation of the shield relative to the positional switch  44  mounted on the headband. 
         [0036]    In this example, wiring  53  includes a path leading from switch  44  to headband light source  20  that is activated by switch  44  to power on lighting source  20  when shield  60  is raised as illustrated in this example by the direction of the rotational arrows. A second positional sensor  41  hosting earth or electromagnets  42  is illustrated in broken boundary indicating a mounted position on the interior surface of shield  60 . The second positional sensor  41  aligns with positional switch  44  when welding shield  60  is lowered. 
         [0037]      FIG. 9  is a side view of welding shield  60  of  FIG. 1  adapted with a positional switching system, the shield lowered to power on the welding shield light source. Welding shield  60  is illustrated in a lowered position relative to headband  64  exposing headband light source  10  to illuminate the workspace. Positional switch  44  fixed to headband  64  is in alignment beneath one of magnets  42  mounted on a positional sensor  41 , which in turn is mounted to the interior surface of shield  60 . As described above, positional sensor  41  is mounted strategically in the arcurate path of rotation of the shield relative to the positional switch  44  mounted on the headband. 
         [0038]    In this example, wiring  53  includes a path leading from switch  44  to welding shield light source  10  that is activated by switch  44  to power on lighting source  10  when shield  60  is lowered as illustrated in this example by the direction of the rotational arrows. The first-described positional sensor  41  and electromagnets or earth magnets  42  is illustrated as fixed to the interior surface of the welding shield in a arcurate rotational path relative to switch  44  on the headband and comes into alignment with switch  44  when the shield is again raised. 
         [0039]      FIG. 10  is a circuitry diagram illustrating a manual lighting control circuit  100  with an automatic positional sensing switch setting. Control circuit  100  represents one embodiment of the present invention. Dial  30  controls the flow of electricity from battery  51  in this example to welding shield light emitter  10 . In this case light emitter  10  is an LED but in another embodiment another illumination device may be used instead. 
         [0040]    Alternate control unit or dial  40  may be provided to control the flow of electricity from battery  51  to headband light emitter  20 . A magnet  45  is mounted on dial  30  and is moved in a rotational path as the dial is physically turned as illustrated by rotational arrow. Dial  40  includes a similar magnet  45   a.    
         [0041]    When magnets  45  and  45   a  are both in the auto position as shown, normally closed (NC) magnetic reed switch  44   c  is closed and normally open (NO) magnetic reed switches  44   d  and  44   a  are open, therefore no current flows from battery  51  to light emitter  10  causing light emitter  10  to be off. If however, helmet  60  is placed in a lowered position, electro magnet  42  is brought close to magnetic reed switch  44   a  causing closure of the switch resulting in current flowing from battery  51  to light emitter  10  illuminating the workspace. 
         [0042]    Similarly, when both magnets  45  and  45   a  are in the auto position as shown NC magnetic reed switch  44   e  is closed and NO magnetic reed switches  44   f  and  44   b  are open, therefore no current flows from battery  51  to light emitter  20  causing light emitter  20  to be off. However, if the welding shield is raised to the uppermost position, magnet  42  is brought close to magnetic reed switch  44   b  causing current to flow from battery  51  to light emitter  20  resulting in illumination of the workspace. 
         [0043]    When control dial  40  is turned is physically turned so that magnet  45   a  is in the ON position, magnetic reed switch  44   f  is closed enabling flow of current from battery  51  to light emitter  20  resulting in illuminating the workspace regardless of whether magnetic reed switch  44   b  is open or closed overriding that circuit causing light emitter  20  to remain on regardless of raising or lowering the helmet. Likewise, when control dial  40  is turned such that the magnet  45   a  is in the off position, magnetic reed switch  44   e  opens blocking current flow from battery  51  to light emitter  20  causing light emitter  20  to remain off regardless of whether magnetic reed switch  44   b  is in the open or closed position. Therefore, light emitter  20  remains off in the manual mode regardless of whether the welding shield is raised or lowered. 
         [0044]    In general use of the welding shield lighting system of the present invention, an operator may don the welding shield adjusting the headband for good fit. In manual mode a user may select from manual settings OFF, Welding Shield Light ON, Headband Light ON, or AUTO. Selecting AUTO cause the system to defer to automatic mode wherein alternate light emitters are powered on based on welding shield position. 
         [0045]    The “automatic” setting uses a positional sensor to control the light emitters. The user may select the desired light emitter by positioning the welding shield in relation to the headband. If the welding shield is in the lowered position, then the helmet light emitter  10  is powered on. If the welding shield is in the raised position, then the headband light emitter  20  is powered on. Each light emitter turns off when the alternate light emitter is activated. 
         [0046]    In the solar cell-enabled charging system, the battery power supply is charged through the use solar of cells  52 , converting energy from the ultraviolet light emission of the welding activity or sunlight into electrical power. Electrical power is communicated by way of power cable/wire  53  and electrical connectors or plugs  54  Supplemental, charging may be allowed for by plugging into an external power source between uses. 
         [0047]    It will be apparent to one with skill in the art that the welding shield and lighting control system of the invention may be provided using some or all of the mentioned features and components without departing from the spirit and scope of the present invention. It will also be apparent to the skilled artisan that the embodiments described above are specific examples of a single broader invention, which may have greater scope than any of the singular descriptions taught. There may be many alterations made in the descriptions without departing from the spirit and scope of the present invention.