Abstract:
A combined welding helmet apparatus is provided. The apparatus allows for several features to be incorporated into a single helmet. Particularly, several face and eye protection elements are incorporated into a single helmet. An integrated internal mechanism allows for selected elements to be functionally positioned while non-selected elements are unobtrusively positioned to a non-functional position. At least three face and eye protection elements are combined in the helmet; a dark filtered welding lens, a lighter filtered lens, and a clear safety plate.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates to protective gear for welders. More particularly, it relates to an improved welding helmet having multiple viewing lenses.  
       STATEMENT OF THE PRIOR ART  
       [0002]     Welding helmets having lenses to attenuate light emitting from the welding torch are well known. These helmets generally are available in two types, a first type having an ambient light responsive liquid crystal lens, and a second type having a manually positionable, visually opaque lens.  
         [0003]     The liquid crystal lens assembly comprises a layer of nematic liquid crystal material sandwiched between opposing parallel plates coated with transparent conductive films. The faces of the plates in contact with the liquid crystal material are treated so as to effect a twisted nematic structure therein which will rotate polarized light passing through the light shutter through 90.degree. Polarizers are disposed on opposite sides of the plates such that by applying an electrical field across the transparent conductive films, the opacity of the liquid crystal light shutter can be changed. In order to render the lens light-transmitting, an electric field must be established across the conductive films. Thus, in the event of power failure, the lens will, theoretically, automatically assume an opaque condition and protect the eyes of the welder, with the obvious drawback that if the welder is not engaged in welding, he/she will be briefly blinded which, in a construction setting could lead to accidents.  
         [0004]     The other type of helmet has a single manually positionable opaque lens element, which is usually pivotable by the movement of the welders head into an operational position. These helmets are structured to position only a single lens element in front of a viewing aperture which may or may not be shielded by a transparent plate.  
         [0005]     Attempts have been made to provide for a number of interchangeable lenses for a welding helmet, but the helmets produced have had drawbacks. For example, U.S. Pat. No. 6,151,711 issued to Edwards on Nov. 28, 2000 discloses a welding helmet which includes a removable lens cartridge assembly which is slidingly received by a slot at the front of the welding helmet. The lens cartridge assembly includes a picture frame slot into which a face lens may be friction fit by insertion from the side. Additional filters and lenses may be held in place within the cartridge by a removable frame assembly. Edwards suffers from the drawback that there is no way to store the additional lenses and thus they are subject to being misplaced. Also, as the lens must be slid into position to cover the viewing aperture, improper positioning of the lens could result in a small gap between the lens frame and the helmet body, with the possibility of injury to the welder.  
       SUMMARY OF THE INVENTION  
       [0006]     The present invention contemplates a combined welding helmet apparatus is provided. The apparatus allows for several features to be incorporated into a single helmet. Particularly, several face and eye protection elements are incorporated into a single helmet. An integrated internal mechanism allows for selected elements to be functionally positioned while non-selected elements are unobtrusively positioned to a non-functional position. At least three face and eye protection elements are combined in the helmet; a dark filtered welding lens, a lighter filtered lens, and a clear safety plate.  
         [0007]     Accordingly, it is a principal object of the invention to provide a new and improved welding helmet having multiple viewing options.  
         [0008]     It is another object of the invention to provide a new and improved welding helmet having multiple viewing options where all of the options are manually selectable.  
         [0009]     It is another object of the invention to provide a new and improved welding helmet having easily accessible means for manually reconfiguring the helmet.  
         [0010]     Finally, it is a general object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is fully effective in accomplishing its intended purpose.  
         [0011]     These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]     Various other objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:  
         [0013]      FIG. 1  shows a plan view of the welding helmet of the present invention.  
         [0014]      FIG. 2  shows a side view, partly in section, of the welding helmet of the present invention positioned on a user&#39;s head.  
         [0015]      FIG. 3  shows a side sectional view of the welding helmet with the plasma cutting lens in the operational position.  
         [0016]      FIG. 4  shows a side sectional view of the welding helmet with the welding lens in the operational position.  
         [0017]      FIG. 5  shows a side sectional view of the welding helmet arranged to allow for full light transmissivity.  
     
    
     DETAILED DESCRIPTION  
       [0018]     Referring now to  FIGS. 1-5 , the welding helmet of the present invention, generally indicated by the numeral  10 , is shown. It can be seen that the welding helmet  10  comprises a relatively large, visually opaque main body  20  having a central viewing aperture  22  formed in the front portion thereof. A standard attachment means  24  is used to secure the main body, and once attached to a user&#39;s head  29 , allows the main body  20  to be pivoted to shield the user&#39;s face. The attachment means  24  is secured to the main body  20  in journaled relation by opposing pivots  23 .  
         [0019]     Selectively positioned proximate the central viewing aperture  22  are at least two lenses for reducing the amount of light transmitted through the viewing aperture. A safety plate or window  26 , which is transparent to allow all light to pass therethrough covers the aperture  22  and serves to deflect debris, sparks, and the like as may be produced by the welding process, or any sawing and grinding processes related-thereto. The aperture  22  and window  26  are positioned perpendicular to the viewing axis  25  to allow for viewing a workpiece therethrough, the workpiece visible through a viewing angle approximately as shown by lines  27 . Hingedly connected to the front panel  31  of the helmet main body  20  is a welding lens  30 , which may be a piece of welder&#39;s glass such as Crook&#39;s Glass which is especially formulated to reduce the transmissivity through the window  26  and also to absorb substantially all ultraviolet and most of the blue light from the work. The lens  30  may be secured to the pivoting lens frame  32  by any conventional means, and may be removably secured to allow for periodic replacements. It can be seen that the lens  30  can be selectively positioned in front of viewing aperture  22  to allow for welding.  
         [0020]     As is well known in the art, welding helmets are useful as protective gear for a variety of tasks besides welding. For example, a welding helmet could be used for any sawing or grinding process as implied above, especially when metals are being worked as flying debris therefrom is heavier and therefore more dangerous than sawdust. To that end, welding helmets having the so-called light responsive lenses have been developed as noted above. These lenses are designed to respond quickly to changes in the ambient light intensity, but require a constant supply of electric current to do so. The present invention contemplates a welders helmet having a sufficient number of auxiliary lenses so that a lens for any task may be manually selected. At present, there are three types of tasks which are facilitated by the use of protective head gear, the welding helmet  10  of the invention therefore has at least three discrete configurations, and means for manually switching to a desired configuration. As previously mentioned, grinding and sawing processes may be performed by viewing the workpiece through window  26  with no other lenses in the user&#39;s line of sight. For welding operations, the lens  30  may be positioned to be in the user&#39;s line of sight as also discussed above.  
         [0021]     A second task commonly performed by welders is the cutting of metals and the like with a plasma torch cutting tool. Plasma arc torches, also known as electric arc torches, are commonly used for cutting, marking, gouging, and welding metal workpieces by directing a high energy plasma stream consisting of ionized gas particles toward the workpiece. These types of torches create a fairly bright arc, but one that does not require a visually opaque lens. A shaded or tinted lens is commonly used for this task as is known by those of skill in the art. To that end, an additional lens  36  is slidably disposed interiorly of the main body  20 . The lens frame  34  for lens  36  is attached to longitudinally extending connecting member  37  by screws or the like which is connected to actuator tab or actuator  38  which can be reciprocally slid within a slot  39  formed in the main body  20 , as indicated by arrows A and B. The forward travel of the actuator  38  is limited by the length of the slot  39 , the ends of which form mutually opposed abutment surfaces  41 . By moving the actuator briskly  38 , the user will hear an audible click indicating that the lens  36  is in the proper position, the click indicating abutment of the actuator with an abutment surface. Other means as would be apparent to one of skill in the art may be used to provide an indication that the actuator has reached the end of its travel. As with the welding lens  30 , frame  34  is preferably configured to allow for periodic replacement of the lens  30 .  
         [0022]     In operation, for grinding and sawing operations, the helmet  10  is configured as shown in  FIG. 5 , by pivoting the welding lens  30  to the horizontal position, and sliding the actuator  38  for lens  36  in the direction of arrow A until it reaches its limit of travel. For welding operations, the welding lens  30  is pivoted or flipped down into the vertical position as shown in  FIG. 4 , thereby entering the user&#39;s line of vision and completely obscuring window  26 . Finally, for plasma torch cutting, welding lens  30  is flipped into the horizontal position, and lens  36  is slid in the direction of arrow B so that the helmet  10  is configured as shown in  FIG. 3   
         [0023]     From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions.  
         [0024]     It is to be understood that the present invention is not limited to the sole embodiment described above, but encompasses any and all embodiments within the scope of the following claims: