Abstract:
An open shipyard feeder for supplying a consumable welding wire on a wire spool to a welding gun. The feeder includes a frame having a base extending in a longitudinal direction between a forward end and a rearward end and which supports the feeder on an underlying surface. The frame further includes a spool support means connected to the frame near the rearward end and which rotatably retains the wire spool relative to the frame allowing the spool to rotate about a spool axis. The feeder includes a wire advancing mechanism mounted on the frame for paying wire from the spool on the spool support to the welding gun. The feeder further includes a control box on the frame near the forward end. The feeder frame is rigid yet light weight and can support the wire feeder on a wide range of underlying surfaces while still being easily transportable.

Description:
[0001]    The present invention is directed to a portable wire feeder and more particularly to an open shipyard style wire feeder. This application claims priority under 35 U.S.C. §119 to U.S. Provisional Application No. 60/333,366 filed Nov. 26, 2001. 
     
    
     
       INCORPORATION BY REFERENCE  
         [0002]    The present invention relates to supplying a consumable welding wire electrode to the welding gun used in a welding operation wherein the location of the welding operation does not remain constant. This can include welding operations at job sites which change day to day or welding operations covering large areas at a single job site. Portable wire feeders are known in the art and are generally shown in Bellefleur U.S. Pat. No. 4,665,300; Rybicki U.S. Pat. No. 6,213,375; Kroll U.S. Pat. No. 4,508,954; Chandler U.S. Pat. No. 6,225,596; Miller U.S. Pat. No. 5,410,126 and Grimm U.S. Pat. No. 5,836,539. These patent are incorporated by reference herein as background information illustrating portable wire feeders.  
         BACKGROUND OF THE INVENTION  
         [0003]    The present invention is particularly applicable for use in connection with shipyard welding and, therefore, the invention will be shown and described with particular reference thereto. However, the invention has much broader application in that it can be used as a portable wire feeder for many applications involving different types of job sites and welding operations.  
           [0004]    It is, of course, well known that wire can be used as an effective welding consumable. Welding wire forms a part of the welding electrode and contributes to the weld pool as filler material. Therefore, the wire feeder needs to supply the welding operation with the welding wire in a consistent and controllable manner. Furthermore, in order to maximize the benefits of utilizing welding wire, the wire must be accurately directed to the weld point of the welding operation at a controlled rate.  
           [0005]    The portable wire feeder must supply the welding operation with the welding wire in a consistent and controllable manner like a standard stationary wire feeder even though it must be capable of repeated movement and use in connection with a wide range of work environments, many of which can be severe. Therefore, the portable wire feeder must not only provide accurate and continuous wire control, it must have additional characteristics not found in stationary wire feeders that are used in controlled environments such as a work shop or factory floor. One such characteristic is that the portable wire feeder must be compact and light weight. Since the portable wire feeder is repeatedly moved, it is advantageous for the portable wire feeder to be lightweight. Furthermore, since on site jobs require the user to haul their tools in a fixed and many times limited space, a compact size is advantageous.  
           [0006]    The portable wire feeder must be rugged. While the traditional wire feeder is typically used in one location over a long period of time, the portable wire feeder is constantly moved and subjected to many adverse conditions. Merely moving the portable wire feeder subjects it to impact forces by the underlying surface when it is placed on the surface and when it is transported in a work vehicle. Furthermore, each time the portable wire feeder is moved, there is a risk that the feeder will be dropped or impacted by other objects. Finally, the portable wire feeder is often used in harsh work environments.  
           [0007]    The portable wire feeder must be easy to use even when the user is wearing protective gear. The user of a welder typically wears, among other protective gear, gloves and face/eye protection. Therefore the portable wire feeder should be easy to grasp and manipulate even with protective gloves. This includes the ability to easily manipulate the portable feeder over uncertain terrain often associated with many job sites and easily load the feeder onto a work vehicle. Furthermore, due to the uncertainty relating to the underlying surfaces, the portable wire feeder must be stable over a wide range of surfaces. This is especially important since the portable wire feeder is often pulled across the underlying surface by its wire guide tube. The controls must also be easily accessible and controllable by the user wearing protective gear and must be rugged.  
           [0008]    The supply of welding wire needs to be easily replaceable under a wide range of conditions and protected against the elements of a harsh work environment. These characteristics often conflict. In this respect, providing protection for the welding wire typically involves a barrier between the wire and the environment. This can prevent easy accessability to and replacement of the welding wire. It is also advantageous to utilize a standard spool of welding wire in order to reduce cost and simplify wire replacement. This can increase the size of the portable wire feeder. Furthermore, providing easy access to an internal wire spool compartment can weaken the overall rigidity of the portable wire feeder.  
           [0009]    Prior art wire feeders and portable wire feeders do not include these characteristics. In this respect, referring to the Chandler patent, a portable welding unit is disclosed which includes a wire feeder. While Chandler&#39;s device is compact, it does not provide protection for all of the components of the wire feeder. As a result, these components can be damaged during use or during the transportation of the feeder to and from the job site. Furthermore, the Chandler device is not easily stored or manipulated over non-flat underlying surfaces due to its narrow base design. The wire feeder disclosed in Bellefleur also is compact. However, Bellefleur&#39;s wire feeder is not easily transportable and it does not provide protection for the controls. Bellefleur also fails to disclose a rigid frame to prevent impact damage. The Miller patent discloses a portable wire feeder which also fails to provide protection for the controls. In fact, the Miller controls are on an outside edge without protection. Furthermore, Miller&#39;s feeder does not include any means for easy movement or manipulation. Another disadvantage associated with the Miller device is that access to the wire supply is restricted.  
         SUMMARY OF THE INVENTION  
         [0010]    In accordance with the present invention, provided is a portable wire feeder is provided for use in connection with shipyard welding operations which includes a frame structure that supports the portable wire feeder on a wide variety of underlying surfaces and protects the internal components from impact while allowing easy access to the internal components, and easy transportation and use of the portable wire feeder. In this respect, a portable wire feeder in accordance with the present invention includes a lightweight yet rigid outer frame structure that is configured for stability. The outer frame further includes accessible grasp points and selectively engageable covers for protecting the internal components while providing easy access thereto.  
           [0011]    The outer frame of a wire feeder according to the present invention defines a rigid outer perimeter. The frame includes a non-parallel base rail structure wherein the base rails are spaced apart and extend away from one another near the rearward end of the frame such that the base is widest at its rearward end. Since the rearward end is also the heaviest portion of the portable wire feeder, the weight of the feeder is concentrated over the widest portion making the structure more stable. Furthermore, this configuration also minimizes tipping when the feeder is on uneven surfaces or when it&#39;s pulled by the wire guide tube that extends out its forward end. The frame further includes sides which extend upwardly and toward one another. This configuration lowers the center of gravity which further increases the stability of the portable wire feeder. In addition, the frame includes front and back portions that protect the internal components and which include access openings for certain internal components. The frame further includes handles for moving and transporting the portable wire feeder with either one or two hands.  
           [0012]    In accordance with another aspect of the present invention, the portable wire feeder includes multiple covers for selectively covering the control box and the wire spool. Both covers are configured to be easily opened and closed even with a gloved hand. Furthermore, these covers can include transparent panels to allow the user to monitor the control box and spool while welding. The control box includes gauges and/or controls for the wire feeder and/or the welding operation and which gauges and controls can be damaged from welding spatter or from impact by other objects. The control box cover is pivotal relative to the frame between an opened and a closed position wherein the gauges and/or controls are protected while in the closed position. Even though the control box and cover are positioned near a center handle for convenience of operation, both are sufficiently spaced from the center handle to allow the user to easily open or close the cover with a gloved hand even while the user supports the feeder by the center grasp handle. The wire spool cover also moves relative to the frame between an opened and a closed position. The spool cover provides protection similar to the protection provided by the box cover.  
           [0013]    In accordance with even another aspect of the present invention, the portable wire feeder includes a spool support that is easily accessible without weakening the frame and without complicating the replacement of the wire spool. In fact, the spool support according to the present invention actually strengthens the frame structure of the portable wire feeder. As stated above, the welding wire is consumable and, therefore, the wire spool must be replaced as the wire is depleted or when the type of wire is changed. The spool support must therefore include a spindle with at least one free end that can receive the wire spool. The spindle according to the present invention has a first end rigidly connected to the frame and a second end which is free to receiving the wire spool. However, the second end includes a latch mechanism that can interengaged with a pivotal frame component such that both ends of the spindle are supported on the frame when latched, and the spindle acts as an additional frame component. The spool support is preferably positioned near the rearward end for increased stability and to prevent the wire spool or support from blocking access to the control box.  
           [0014]    In accordance with yet another aspect of the present invention, the portable wire feeder includes multiple handles spaced on either side of the center of gravity of the portable wire feeder. This allows for two handed and balanced lifting which makes the feeder easier to transport. More particularly, the two handles are spaced from one another on either side of the heavy wire spool. One handle is positioned between the rearward end and the spool axis and the other handle is more centered and is between the forward end of the feeder and the spool axis. The center handle is also closer to the actual center of gravity so that the user can use his/her free hand for other purposes such as to operate the controls. In addition, the handles are also structural components of the frame to further strengthen the frame without adding unnecessary weight.  
           [0015]    In accordance with a further aspect of the present invention, the portable wire feeder further include wheels which can engage an underlying surface to allow the feeder to freely roll on the surface. Since easy movement is not always advantageous, the wheels can be designed for varying degrees of movement of the feeder. The first configuration allows for continuous wheel engagement which allows the feeder to freely move on flat surfaces at all times. A second configuration allows for the wheels to engage the underlying surface only when the front of the feeder is raised. This configuration allows for easy movement only when desired without modification to the wheels. The third configuration is a combination of the first two. With respect to the second configuration, the frame includes an upwardly extending portion which supports the wheel axles such that the axles to are spaced sufficiently above the bottom of the base so the wheels do not engage the underlying surface when the base is resting flat on the surface. Engagement by the wheels is initiated only when the forward end of the feeder is lifted upwardly relative to the rearward end. This allows the user to decide when the portable wire feeder is to be free to roll on the underlying surface and when it is to be stationary. In the third configuration, front casters are provided which are pivotably connected to the forward end of the base for movement about a horizontal caster axis between an operating position and a retracted position. When the casters are in the retracted position they are spaced from the underlying surface when the bottom of the feeder is resting on the surface. However, when the casters are in the operating position, the bottom of the feeder is spaced from the underlying surface and the casters engage the surface similar to the first configuration. This allows the user to quickly adapt the feeder between a highly mobile feeder and a stationary feeder.  
           [0016]    In accordance with even another aspect of the present invention, the portable wire feeder includes a control box that can be removed from the feeder. This provision allows the portable wire feeder to be operated remotely thereby preventing the user from having to return to the feeder to make an adjustment during the welding operation.  
           [0017]    The primary object of the present invention is the provision of a portable wire feeder which is light weight yet rigid so that it can be easily transported and withstand many adverse conditions.  
           [0018]    Another object is the provision of a portable wire feeder of the foregoing character which is easy to maneuver yet is capable of being maintained in a set position.  
           [0019]    Still another object is the provision of a portable wire feeder of the foregoing character which includes at least two handles spaced on either side of the center of gravity for the portable wire feeder.  
           [0020]    A further object is the provision of a portable wire feeder of the foregoing character wherein one of the handles is near the center of gravity for the portable wire feeder so that one hand can be used to support the feeder while the other hand can operate controls on the feeder.  
           [0021]    Yet a further object is the provision of a portable wire feeder of the foregoing character which includes a spool support for a wire spool that allows full and easy access to the wire spool while also acting as a structural component of the frame when latched.  
           [0022]    Still another object is the provision of a portable wire feeder of the foregoing character which includes wheels that are selectively engageable with an underlying surface.  
           [0023]    Still another object is the provision of a portable wire feeder of the foregoing character wherein the wheels are attached to fixed axles that are spaced above the base of the frame such that the wheels only engage the underlying surface when its forward end is lifted relative to the rearward end.  
           [0024]    Yet a further object is the provision of a portable wire feeder of the foregoing character which includes casters on the forward end of the base which are retractable such that they pivot between an operating position wherein the casters and the wheels engage the underlying surface and a retracted position where the caster and the wheels are spaced from the underlying surface as the bottom of the frame rests on the surface.  
           [0025]    A further object is the provision of a portable feeder of the foregoing character which includes a control box cover which is pivotal between an open and a closed position wherein the user can grasp the handle nearest the control box in one hand and operate the box cover and the controls with the other hand.  
           [0026]    Yet another object of the present invention is the provision of a portable wire feeder of the foregoing character which includes a retractable spool cover which protects the wire spool and which can be quickly retracted to gain access to the wire spool.  
           [0027]    Another object of the present invention is the provision of a portable feeder of the foregoing character which includes a base that is wider near its rearward end thereby making the portable wire feeder more stable.  
           [0028]    Yet a further object is the provision of a portable wire feeder of the foregoing character wherein the center of gravity of the portable wire feeder is set low and near the rearward end near the widest portion of the base making the portable wire feeder stable on a wide variety of surfaces.  
           [0029]    Even a further object is the provision of a portable wire feeder of the foregoing character which includes a control box that is removable from the portable wire feeder allowing the user to control the wire feeding and/or the welding operation from a remote location.  
           [0030]    Another object is the provision of a portable wire feeder of the foregoing character which utilizes components that are economical to manufacture, easy to use in the field while still being light weight and durable. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0031]    The foregoing objects, and others, will in part be obvious and in part be pointed out more fully hereinafter in connection with a written description of preferred embodiments of the present invention illustrated in the accompanying drawings in which:  
         [0032]    [0032]FIG. 1 is a perspective view of a portable wire feeder in accordance with the present invention wherein the box cover is in the opened position, the spool cover is in the closed position and the locking arm of the spool support is shown in both the opened and latched conditions;  
         [0033]    [0033]FIG. 2 is a front elevational view of the portable wire feeder shown in FIG. 1 wherein the box cover is shown in both the opened and closed positions;  
         [0034]    [0034]FIG. 3 is a side elevational view looking from right to left in FIG. 2 and wherein the box cover is shown in the closed position;  
         [0035]    [0035]FIG. 4 is a side elevational view of the other side of the portable wire feeder and wherein the box cover is shown in the closed position;  
         [0036]    [0036]FIG. 5 is a top view of the portable wire feeder shown in FIG. 1 wherein the box cover is in the closed position;  
         [0037]    [0037]FIG. 6 is a sectional elevational view of the portable wire feeder taken along line  6 - 6  in FIG. 3;  
         [0038]    [0038]FIG. 7 is a sectional view of the control box and cover taken along line  7 - 7  in FIG. 1;  
         [0039]    [0039]FIG. 8A is a partial side elevational view of yet another embodiment of a portable wire feeder in accordance with the present invention which includes casters shown in a retracted position;  
         [0040]    [0040]FIG. 8B is a partial side elevational view of the portable wire feeder shown in FIG. 8A wherein the casters are shown in an operating position;  
         [0041]    [0041]FIG. 9 is a side elevational view of one side of another embodiment of a portable wire feeder in accordance with the present invention; and,  
         [0042]    [0042]FIG. 10 is a side elevational view of one side of yet other embodiments of a portable wire feeder in accordance with the present invention. 
     
    
     DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0043]    Referring now in greater detail to the drawings wherein the showings are for the purpose of illustrating preferred embodiments of the invention only, and not for the purpose of limiting the invention, FIGS.  1 - 7  illustrate an open shipyard or portable wire feeder  10  which includes a frame  12  that can come in many forms without departing from the invention herein. Frame  12  is a compilation of several structural elements that can be either sheet steel or tubular members. Portable wire feeder  10  is shown in its preferred configuration wherein it includes a base  14  comprised of side rails  16  and  18  that are a unified component with sides  20  and  22  respectively. However, it should be noted that side rails  16  and  18  which will be discussed hereinafter could be formed by a separate member including tubular members. Side rails  16  and  18  extend between a forward end  24  and rearward end  26  in a longitudinal direction of feeder  10 . However, side rails  16  and  18  are nonparallel and extend away from each other toward the rearward direction such that base  14  has a rear width between arrows  28  which is greater than the front width between arrows  30 . More particularly, it is preferred that the rear width is approximately 3.5 inches wider than the front width. Base  14  further includes a bottom panel  32  which extends in the longitudinal direction generally between the forward and rearward ends  24  and  26  respectively and between side rails  16  and  18 . Bottom panel  32  includes a downwardly extending base portion  33  adjacent the forward end thereof and having a bottom surface  34  for engaging an underlying surface  36 .  
         [0044]    Frame  12  further includes a back member  40  that extends between rails  16  and  18 . Back member  40  extends horizontally from base  14  and includes upward bends  41  and  42 . Member  40  is shown as a tubular member extending rearwardly and upwardly from the rearward end of base  14  and including a handle  42 . However, back member can take many forms including two independent extensions that are separate from handle  42 . Wheels  44  and  46  include wheel surfaces  48  and  50  respectively for engaging underlying surface  36  and are secured to back member  40  by an axle  52  which could be two independent axles. Axle  52  is positioned on back member  40  such that wheel surfaces  48  and  50  respectively extending below the bottom edges  56  and  58  of side rails  16  and  18  respectively. Essentially, wheel surfaces  48  and  50  extend below bottom edges  56  and  58  the same distance as bottom surface  34  and, therefore, portable wire feeder  10  engages underlying surface  36  at three points, namely, bottom surface  34 , wheel surface  48  and wheel surface  50 . As a result, when feeder  10  is at rest on underlying surface  36 , it will remain at a set point. However, if the user lifts forward end  24 , feeder  10  can be easily rolled on surface  36 . While bottom surface  34  is shown to be flat, it could be arcuate so that only a portion of the surface contacts underlying surfaces  36 .  
         [0045]    Sides  20  and  22  extend upwardly from side rails  16  and  18  respectively and also extend toward one another such that the top edges  70  and  71  are closer to one another than bottom edges  72  and  73 . This lowers the center of gravity of feeder  10  making it even more stable. It is preferred that the top edges  70  and  71  are approximately 2 inches closer together than bottom edges  72  and  73 . Top edges  70  and  71  are joined by a center handle  74  which acts as both a grasp point for the user and a structural component of frame  12 . Furthermore, the compound angle formed by the sides extending toward one another and the front of the base being narrower than the back of the base makes edges  76  and  78  parallel to one another which will be discussed below in greater detail. Side  20  further includes side openings  80  and  82  and side  22  further includes side opening  84  which will also be discussed in greater detail below.  
         [0046]    Feeder  10  further includes a spool support  90  having a spindle  92  having a base portion  93  at a first end  94  and a cylindrical portion  95  extending toward a second end  96 . Base portion  93  is connected to side  22  by fasteners  97  and includes a stop flange  98 . While fasteners  97  are shown, other means such as welding, can be used to secure spindle  92  to side  22 . Cylindrical portion  95  is shaped to receive a central opening  99  of a wire spool  100  allowing spool  100  to freely rotate about a spool axis  102 . It should be noted that while no rotation restriction device or brake is shown in connection with the rotation of wire spool  100 , any such mechanism known in the art could be used in connection with feeder  10  without departing from the present invention. Spindle  92  further includes a first latch component  104  at second end  96  which includes a tapered nose  106  and a locking groove  108 . Support  90  further includes frame bracket  110  secured to frame  12  and pivot bracket  112  pivotally connected to frame bracket  110  by a pivot pin  114 . Locking arm  116  is secured to pivot bracket  112  and is adapted to pivot between an opened condition  118  and a latched condition  120 , as shown in FIG. 1, and includes a second latch component  122  near end  124  of the locking arm. Second latch component  122  is rotatable relative to locking arm  116  for selectively engaging locking groove  108  to rigidly secure arm end  124  to spindle  92 , thereby further supporting wire spool  100  and further stiffening frame  12 . In essence, spindle  92  acts as an additional structural component of frame  12  when in the latched condition. However, when latch component  122  is released form locking groove  108 , locking arm  116  is allowed to freely rotate about pivot pin  114  to the open condition  118 . While only one type of latch is discussed, it should be noted that other latches known in the art can be used to rigidly secure locking arm  116  to spindle  92 . When in the open condition  118 , wire spool  100  can be easily and quickly removed from spindle  92  through side opening  82 . Side opening  82  is shaped and sized to be large enough to accept the largest wire spool designed for use with feeder  10 . Openings  80  and  84  provide access to the wire advancing mechanism and the electrical connections which will be discussed below.  
         [0047]    Support  90  further includes a spool cover  126  comprising a vertical side panel  128  having a peripheral edge  130  and an arcuate top panel  132  extending transversely across the wire reel from at least a portion of edge  130 . Vertical panel  128  includes a central opening  134  shaped to receive spindle  92  allowing spool cover  126  to pivot about spool axis  102  between an opened position, not shown, and a closed position shown in FIG. 1. Vertical panel  128  of spool cover  126  is pivotally secured to flange  98  by fasteners  140 . As a result, when the user replaces wire spool  100 , spool cover  126  can be pivoted to the open position where it will not obstruct the users access to or view of spool  100 . However, when spool cover is in closed position  138  it protects spool  100  and the wire supply from spatter and impact. In another embodiment, not shown, top panel  132  is transparent so that the user can monitor the wire supply.  
         [0048]    Feeder  10  further includes a wire advancing mechanism  150  mounted to frame  12  near forward end  24 . Mechanism  150  includes an inlet  156  shaped to receive welding wire  152  from wire spool  100  and a plurality of pinch rollers not designated numerically, to direct wire  152  toward outlet  158  and into wire guide tube  160  in an operating direction  154 . Further details on mechanism  150  and wire straightening devices are not given in that they are known in the art and not part of the present invention.  
         [0049]    Feeder  10  further includes a control box holder  170  which selectively retains a pendant control box  172 . Holder  170  includes a bottom retainer  174  having top and bottom edges  176  and  178  respectively. Top edge  176  has an inwardly facing lip  180  and bottom edge  178  is secured to a bottom plate  182 . Box holder  170  further includes a top retainer  184  having top and bottom edges  186  and  188  respectively wherein bottom edge  188  is connected to the opposite end of bottom plate  182  opposite retainer  174 . Bottom retainer  174 , top retainer  184  and plate  182  are shaped to receive control box  172 . Box  172  is selectively retained within box holder  170  by the interengagement with inwardly facing lip  180  and an inwardly facing edge  190  of a latch  192  that is biased towards control box  172  by a spring which is not shown. Latch  192  further includes a thumb extension  194  which allows the user to urge latch  192  away from control box  172  thereby releasing box  172  from holder  170 . As a result, the control box can be removed from feeder  10  thereby providing the ability to control the wire feeder at a remote location. It should be noted that other types of selectively engageable mechanisms, such as is shown in FIG. 10, could be used to secure box  172  to feeder  10 . Control box  172  is operatingly connected to the other mechanisms of the wire feeder by a control wire  195 . Control box  172  can have one or more of the gauges and/or controls  196  utilized to control and maintain the wire feeder and/or the welding operation. The gauges and/or controls are those known in the art and, therefore, are not be discussed in detail herein.  
         [0050]    A control box cover  198  provides protection for gauges and/or controls  196  from weld spatter or impact by other objects. Box cover  198  is pivotal about cover axis  200  relative to frame  12  between an opened position  202 , shown in FIG. 1, and a closed position  203 , shown in FIG. 4, and the gauges and/or controls are protected while the cover is in the closed position. Cover  198  includes cover plate  204  having a first edge  205  facing handle  74  and an second edge  206  opposite to first edge  205 . Plate  204  is shown to be transparent so that gauges/controls  196  can be monitored even during use of feeder  10 . In another embodiment, discussed below, cover plate  204  includes a transparent window portion over the gauges and/or controls. In even another embodiment, not shown, none of cover plate  204  is transparent. Cover  198  is connected by a pivot pin  207  and arms  208  to sides  20  and  22  which allows the cover to pivot between opened and closed positions  202  and  203 , respectively, about axis  200 . Since top edges  76  and  78  are parallel to one another and plate  204  is essentially rectangular, side edges  209  and  210  of cover plate  204  are parallel to edges  76  and  78  when in the closed position. Even though control box  172  is positioned near handle  74  and pivot pin  207  is centered in handle  74 , edge  205  is sufficiently spaced from handle  74  to allow the user&#39;s hand to grasp handle  74  and pivot cover  198  simultaneously.  
         [0051]    Feeder  10  further includes a front panel  211  on forward end  24  of the frame which further protects the feeder&#39;s internal components. Front panel  211  can include outlets  212  for power cables  214  which supply the electrical power necessary for the welding operation. Cables  214  are electrically connected to an electrode head  216  which extends forwardly from advancing mechanism outlet  158  and provides the electrical connection between the welding power supply and the welding operation. Head  216  is secured to feeder  10  and has an outlet  218  connected to wire guide tube  160 . Since wire feeder  10  is often pulled by tube  160 , the connection between tube  160  and head  216  includes strain relief  232  and the connection between welding gun and tube includes strain relief  234 . Frame  12  further includes cross member  236  which acts as a forward handle for feeder  10 .  
         [0052]    Panel  211  further includes a power switch  220  that is protected by a pair of switch protectors  222  that extend forwardly of panel  211 . With the power switch conveniently placed on an outer surface of feeder  10 , switch protectors  222  provide protection against impact damage.  
         [0053]    Wire guide tube  160  is attached to outlet  218  of head  216  on one end and on the other end to a welding gun  224 . Guide tube  160  is sufficiently long enough to allow the user to freely move about a larger welding area while feeder  10  remains at a set point. Gun  224  can be conveniently stored in gun holder  226  that is secured to frame  12 . Holder  226  is a tubular member having a top opening  228  for receiving gun tip  230 . In order to provide a convenient and easily movable welding package, feeder  10  also includes power supply inlet  240 , gas supply inlet  242  and electrical cord  244  extending rearwardly of base rearward end  26 . Power supply  240 , gas supply  242  and cord  244  are know in the art and are not be discussed in detail herein. However, power supply  240 , gas supply  242  and cord  244  preferably extend out from rearward end  26  so they conveniently extend out the end opposite to wire guide tube  160  and control box  172 . In addition cords  240 ,  242  and  244  can include strain reliefs which are not shown. The rear extending cords provide improved movement characteristics of feeder  10  and help keep the cords away from the welding operation and the spatter produced therefrom.  
         [0054]    In the following discussions concerning other embodiments, the components of portable wire feeder  10  which remain the same, as discussed above, will include the same reference numbers as above.  
         [0055]    Referring to FIGS. 8A and 8B, shown is a portable wire feeder  250  which includes a different wheel configuration. In this respect, feeder  250  does not include downwardly extending base portion  33  which provides the third point of contact for feeder  10  discussed above. Further, as will be appreciated from FIG. 5, feeder  250  includes a pair of wheels  252  which rotate about a wheel axle  256  that is secured to back member  40  such that wheel surfaces  260  of the wheels are spaced from underlying surface  36  when a bottom surface  264  engages underlying surface  36 . On feeder  250 , axle  256  is spaced further up back member  40  to provide the spacing between wheel surfaces  260  and underlying surface  36  when bottom  264  is resting on surface  36 . Lifting forward end  24  engages wheel surfaces  260  against underlying surface  36 . Feeder  250  further includes a pair of front casters  270  joined to side rails  16  and  18  near forward end  24 . Each caster  270  is pivotal about a corresponding vertical stem  274  that works in connection with trailing wheels  278  to allow feeder  250  to be easily rolled on surface  36  in any direction. Casters  270  can also pivot about a corresponding horizontal caster axis  282  between a retracted position  286  and an operating position  288 . When in the retracted position, wheels  278  are spaced above bottom surface  264  such that surface  264  engages underlying surface  36  and, as mentioned above, wheel surfaces  260  of wheels  252  are also spaced above underlying surface  36  when surface  264  engages the latter. When casters  270  are pivoted about their caster axis  282  into operating position  288 , casters  270  engage underlying surface  36  and raise the forward end of feeder  250  sufficiently to bring wheel surfaces  260  of wheels  252  into engagement with surface  36 . This provides for easy movement of feeder  250  on surface  36 . Furthermore, this configuration allows feeder  250  to be maintained in a set position or to be easily moved based on the needs of the user.  
         [0056]    Referring to FIG. 9, a portable wire feeder  300  is shown which includes yet a different wheel configuration which permanently engages underlying surface  36 . In this respect, as will be appreciated from the showing of feeder  10  in FIGS. 4 and 5, feeder  300  includes wheels  44  and  46  having wheel surfaces  48  and  50  respectively for engaging underlying surface  36 . However, feeder  300  does not include the downwardly extending base portion  33  of feeder  10 . Rather, feeder  300  includes a pair of casters  302  which are rigidly connected to frame  12  on opposite sides of the frame. Casters  302  include vertical pivot pins  306  for allowing rotation of corresponding trailing wheels  310  about a vertical axis. Since casters  302  are mounted in affixed operation position, the casters along with wheel surfaces  48  and  50  engage surface  36  and permanently set feeder  300  in a moveable condition for easy movement on flat and level underlying surfaces.  
         [0057]    Referring to FIG. 10, even yet other embodiments are shown. First, portable wire feeder  350  includes a back member  352  having a rear handle  354 . Back member  352  is tubular and is U-shaped in a single plane. In this respect, unlike member  40  of feeder  10 , which extends horizontally from base  14  and includes upward bends  41  and  42 , member  352  extends upwardly directly from base  14 . There are no upward bends in member  352 . Feeder  350  further includes axle supports  356  extending horizontally from base  14  which support a rear axle  358 . Wheels  44  and  46  are rotationally secured to axle  358 .  
         [0058]    Second, feeder  350  includes an additional spool support  360  which extends vertically between base  14  and spindle  92 . Spool support  360  further strengthens frame  12  to better support wire spool  100 .  
         [0059]    Third, feeder  350  comprises a control box holder  370  which selectively retains a pendant control box  372 . Box  372  is substantially similar to box  172  and, therefore, will not be discussed in detail. However, a bottom  374  of box  372  includes a plurality of locking tabs  376  having heads  378  and shanks  380 . Holder  372  includes a base plate  382  having a mating set of tab slots  384  shaped and positioned to receive tabs  376 . In this respect, slots  384  have head receiving portions  386  which are large enough to allow the respective heads  378  to penetrate base plate  382 . Slots  384  further include a narrow portion  388  which are sized to only allow penetration by shanks  380 . As a result, as tabs  376  enter narrow portions  388 , heads  378  prevent box  372  from being pulled outwardly from plate  382 . In order to remove box  372  from feeder  350 , it must first be moved upwardly and then outwardly relative to plate  382 .  
         [0060]    While considerable emphasis has been placed on the preferred embodiments of the invention illustrated and described herein, it will be appreciated that other embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the invention. Accordingly, it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.