Abstract:
A body panel smoothness inspection light support system is provided having a movable joint and a rotatable sliding contact electrical power connection, minimizing the tendency for a power cord to wear or fray.

Description:
FIELD OF THE INVENTION 
   The present invention relates generally to automotive dent repair tools and more particularly, to a body panel smoothness inspection light support device having a movable joint and a rotatable sliding contact electrical power connection. 
   DESCRIPTION OF THE RELATED ART 
   In automotive body dent repair, lights are used to help to locate dents and other defects in body panels, prior, during and after repair to locate imperfections. For example, by placing a fluorescent light adjacent a panel that appears smooth to the naked eye, but has small imperfections, the reflected shape of the light tube from the body panel at a variety of angles will appear warped at the sites of the imperfections, thus tending to reveal to a skilled body work mechanic the locations and extent of such imperfections. 
   Although the employment of such light inspections are important in all body work, the need to accurately locate dents and imperfections in body panels is particularly important in paintless dent repair, where the body filler and/or sanding used in conventional body repair cannot be employed. 
   In order to properly position the lighting necessary for such inspections, the lighting fixture should be positionable in many positions and at many angles during the course of a repair. Incident light from many different angles allows an experienced worker to observe dents and other imperfections on the surfaces of cars or trucks by the way light is reflected off of the surface. During the course of a repair project, an inspection light may be positioned and repositioned tens or even hundreds of times. 
   Commonly, some type of mechanism is used to support the light in a fixed position for a period of time while a repair project is underway. For example, a stand type of support can be used to support a light while a person removes a dent from a body panel of a car or truck. Referring to  FIG. 1  of the drawings, the reference numeral  100  generally designates such a conventional, movable support for a light. The support  100  comprises a light  102 , a first movable joint  104 , a horizontal arm  106 , a second movable joint  108 , a vertical support  112 , a power cord  110 , and a support base  114 . 
   In order for the support  100  to maintain a lighting position, the components are interconnected to one another. The support base  114  is rigidly attached orthogonally to one end of the vertical support  112 . The vertical support  112  is then rigidly coupled to one end of the second movable joint  108 . The second movable joint  108  is then coupled to the horizontal arm  106  at a point along the axis of the horizontal arm  106 , allowing for limited angular positioning of the horizontal arm  106 . Then, the first movable joint  104  is rigidly coupled coaxially to an end of the horizontal arm  106 . The first movable joint  104  is then coupled to the light  102  at a point along the axis of the light  102 , allowing for limited angular positioning of the light  102  about another axis. However, neither case permits 360 degree movement about an axis. 
   The light position is maintained as a result of the position of the movable joints present in the support  100 . During use of the light, the work person positions and repositions the light by rotating joints  104  and  106 . 
   Referring to  FIGS. 2A and 2B  of the drawings, first movable joint  104  comprises a horizontal arm  106 , a pitch axle  204 , a lower support  206 , and the light  102 . Generally, the light  102  would be rigidly attached to an end of the vertical support  112  or to an end of the horizontal support arm  106 . The lower support  206  is mechanically coupled to the light  102  to allow limited angular rotation about the axis  210 . The lower support  206  is mechanically coupled to the horizontal arm  106  to allow limited angular rotation about the pitch axle  204 . The horizontal arm  106  can then be rigidly coupled to another component, such as the light  102 . However, when the first movable joint  104  is utilized in conjunction with the support  100 , the power cord  110  is bent and re-bent at large angles and can be easily damaged. The support  100  is commonly used in applications where the lighting position is frequently changed. For example, when performing paintless dent repair, the lighting position can be changed tens or even hundreds of times for a single vehicle. Due to the frequency of movement, the cord  110  will frequently fray or otherwise become damaged, often where the cord  110  is attached to the light. The damage can cause exposed wire carrying 110 VAC that can be potentially lethal, as well as terminating function of the light. In addition to causing a danger of electrocutions, these short circuits delay the work and can shut off electricity to other areas of the plant, even where the body repair work is not being performed. Even if the light fixture itself can be easily replaced with a spare, it may take some time to locate the affected circuit breaker in the plant, thus delaying the work of many persons in the plant. Furthermore, because the support  100  does not provide a full 360 degrees of possible angular positioning in both axes, the light  102  is restricted in the positions it can take. 
   Therefore, there is a need for a method and/or apparatus for better coupling a power cord to a support structure and light that addresses at least some of the problems associated with conventional methods and apparatuses for providing inspection lighting. In particular, there is a need for an automotive dent repair inspection light support system that facilitates repetitive, multiple repositioning at any desired angle or position that will minimize the tendency to damage or fray power cords supplying power to the lights. 
   SUMMARY OF THE INVENTION 
   In one embodiment, an inspection light support device is provided comprising a first support member rotatably movable with respect to a vertical support about a first axis and having a degree of friction between the first support member and the base that is sufficient to maintain the first support member in a static position against the force of gravity unless intentionally moved to another position by manually applied force and a second support member rotatably movable with respect to the first support member about a second axis by means of a rotatable connection having a first part and a second part. One of the first and second parts includes a plurality of circular contacts insulatedly separated from one another and the other one of the first and second parts includes a plurality of contact elements, each of the contact elements being resiliently urged against one of the circular contacts to establish a sliding electrical connection between them permitting full axial relative rotation between them. The device also includes a first plurality of electrically conductive wires extending from one of either the plurality of circular contacts or the plurality of contact elements to a light, a second plurality of electrically conductive wires extending from the other of the plurality of circular contacts or the plurality of contact elements to a power cord, and a mount for mounting the inspection light to the second support member. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which: 
       FIG. 1  is an elevation view depicting a conventional light support; 
       FIGS. 2A and 2B  are each side views of a conventional movable joint, each view being orthogonal to the other; 
       FIG. 3  is an elevation view depicting a light support that utilizes a rotatable joint in accordance with an embodiment of the present invention; 
       FIGS. 4A and 4B  are each side views of the rotatable joint of the light support depicted in  FIG. 3 , each view being orthogonal to the other; 
       FIGS. 5A ,  5 B, and  5 C are each side views of the rotatable joint of the light support depicted in  FIG. 3 ,  FIGS. 5B and 5C  of which are orthogonal to the other and  FIG. 5A  of which shows the same view as  FIG. 5B , but is partly in section to reveal in a simplified manner the routing of the power cord conductors to conductive commutator rings on the rotatable joint; 
       FIG. 6A  depicts a section view of the rotatable joint of  FIG. 4A , taken along the line  6 A, showing resilient contacts of the rotatable joint; 
       FIG. 6B  depicts a section view of the rotatable joint of  FIG. 6A , taken along the line  6 B, showing resilient contacts of the rotatable joint; 
       FIG. 7A  is an elevation view of the rotatable joint of the light support depicted in  FIG. 3 , showing the axle coupling the horizontal arm and the rotatable joint; and 
       FIG. 7B  is an elevation view, partly in cut-away, showing, in a cut-away portion of the light fixture, the routing of the conductive wires from the rotatable joint to the light. 
   

   DETAILED DESCRIPTION 
   In the following discussion, numerous specific details are set forth to provide a thorough understanding of the present invention. However, those skilled in the art will appreciate that the present invention may be practiced without such specific details. In other instances, well-known elements have been illustrated in schematic or block diagram form in order not to obscure the present invention in unnecessary detail. 
   Referring to  FIG. 3  of the drawings, the reference numeral  300  generally designates a light support that utilizes a rotatable joint in accordance with an embodiment of the present invention. The support  300  comprises a light  102 , a rotatable joint  304 , a horizontal arm  106 , a universal joint  108 , a vertical support  112 , a power cord  110 , and a support base  114 . 
   In order for the support  300  to maintain a lighting position, the components are interconnected to one another. The support base  114  is attached to one end of the vertical support  112 . The vertical support  112  is then coupled to one end of the universal joint  108 . The second universal joint  108  is then coupled to the horizontal arm  106  at a point along the axis of the horizontal arm  106 , allowing for angular rotation of the horizontal arm  106 . Then, the rotatable joint  304  is coupled to an end of the horizontal arm  106 . The rotatable joint  304  is then coupled to the light  102  at a point along the middle of the light  102 , allowing for angular rotation of the light  102  about two orthogonal axes. 
   The rotatable joint  304  allows for pitch and azimuthal control of the light  102 , while minimizing bending of cord  110  position due to changes in the azimuth and pitch angles. As a result of the constant cord  110  position, the time to damage a cord  110  is dramatically increased. Therefore, overhead costs for body repair could be decreased. 
   Referring to  FIGS. 4A and 4B  of the drawings, the joint  304  comprises a rotatable first part  412 , a rotatable second part  404 , an attachment plate  402 , the power cord  110 , and an extension  408 . 
   The attachment plate  402  couples the joint  304  to the light  102  of  FIG. 3 . From there, power wires  406  to the light can protrude from the joint  304  to the light  102 . Then, the rotatable second part  404  and the extension  408  are coupled to the attachment plate  402 . The power cord  110  is then coupled to the rotatable first part  412 , and the rotatable first part  412  is also coupled to the rotatable second part  404 . As a result the position and angle angle of the light  102  can be controlled by twistably rotating the rotatable first part  412  with respect to rotatable second part  404  about axis  420 . The coefficient of static friction between the rotatable second part  404  and the rotatable first part  412  can be such that the rotatable second part can be moved by the application of a nominal amount of torque (desirably, between about 1 and about 10 ft-lbs) but will remain in a static position otherwise. Pitch control of the light  102  can be achieved by mounting the horizontal arm  106  to the rotatable first part  412  through a pitch axle  414  and by rotating the light about the pitch axle  414 . Also, the coefficient of static friction between the horizontal arm  106  and the rotatable first part  412  can be such that horizontal arm  106  can be overcome by the application of a nominal amount of torque (desirably, between about 1 and about 10 ft-lbs), but will remain in a static position otherwise. Alternatively, counterbalancing springs could be used to maintain the parts in a static position when it is not desired to move them. 
   Referring to  FIGS. 5A ,  5 B, and  5 C of the drawings, the reference numeral  412  generally designates the rotatable first part including slidable conductor elements permitting power to be supplied to the light while permitting the light to be repositioned in a variety of positions and angles. The rotatable first part comprises a U-coupler  504 , a power cord  110 , a first insulating ring  526 , a first conductor ring  506 , a second insulating ring  528 , a second conductor ring  508 , a third insulator ring  530 , and a third conductor ring  510 . 
   The functionality of the rotatable first part  412  occurs by carrying power to the conductive rings. Power can be carried to the rotatable first part  412  through a three-line cord  110 , wherein the three lines correspond, respectively, to a hot line, a return line, and a ground line. A portion of rotatable second part  404  configured as a cylindrical bushing (not shown in  FIGS. 5A and 5B ) protrudes coaxially from the bottom of the U-coupler  504  and is sized so that the conductive rings  506 ,  508  and  510  rotatably fit inside it. The first insulating ring  526  is mounted over a partially cylindrical support (not shown in  FIGS. 5A and 5B ) adjacent to the bottom of the U-coupler  504 . The first conductive ring  506  is also mounted over the partially cylindrical support (not shown) adjacent to the first insulating ring  526 . The second insulating ring  528  is mounted over the partially cylindrical support (not shown) adjacent to the first conductive ring  506 . The second conductive ring  508  is mounted over the partially cylindrical support (not shown) immediately adjacent to the second insulating ring  528 . The third insulating ring  530  is mounted over the partially cylindrical support (not shown) adjacent to the second conductive ring  508 . The third conductive ring  508  is mounted over the partially cylindrical support (not shown) immediately adjacent to the third insulating ring  530 . Each of the conductive rings can be composed of brass, copper, aluminum, steel or another metal suited to conduct electricity and capable of withstanding the rigors imposed by friction. The insulating rings are typically composed of a plastic or another material with a low conductivity. 
   The power cord  520  then carries the power to the rotatable U-coupler  412 . The power cord comprises a first power line  520 , a second power line  522 , and a third power line  524 . Each of the three power lines further comprises a copper wire for carrying current. The first power line  520  is coupled to the first conductive ring  506 . The second power line  522  is coupled to the second conductive ring  508 , and the third power line  523  is coupled to the third conductive ring  510 . Each of the respective power lines can be coupled to a conductive ring, through mechanical attachments, such as a bolt, screw, or friction, or may be soldered. 
   Additionally, for the purposes of safety, the third conducting ring should be attached to the grounded power line. Typically, a washer (not shown) is placed between the rotatable second part  404  of  FIG. 4  and the U-coupler  504 . The washer (not shown) is usually composed of a metallic alloy, such as steel, because of the durability associated with metallic alloys, like steel. However, metallic washers may conduct electricity to bolts or screws that may be used to secure the joint  304  of  FIG. 4 . Therefore, the first conductive ring  506  and the second conductive ring would each be individually coupled to either the hot line or the return line. 
   The feed of electricity from the cord  110  is then further propagated to the light  102  of  FIG. 3  through contacts in the attachment plate  402  and extension  408  of  FIG. 4 . Referring to  FIG. 4  of the drawings, the reference numeral  600  generally refers to the lower assembly of the rotatable joint, depicted in greater detail. The lower assembly  600  comprises rotatable second part  404  and the extension  408 . 
   The rotatable second part  404  is the main structural member of the lower assembly  600 . The rotatable second part  404  is a notched cylindrical tube, wherein the walls are between approximately one quarter of an inch and three eighths of an inch thick. The extension  408 , though, can be a parallelepiped with three distinct cross sections of different sizes, which is then coupled to the rotatable second part  404 . 
   The extension  408  then further comprises a first contact element  608 , a second contact element  610 , a third contact element  612 , a first spring  620 , a second spring  622 , a third spring  624 , a first lead  614 , a second lead  616 , and a third lead  618 . Each of the three contact elements protrudes from one of the surfaces that possess the intermediate cross sectional areas of the three distinct cross sectional areas. Each of the contact elements is composed of a conductive material, such as brass, copper, aluminum, steel or another metal, and which is capable of withstanding the rigors of friction. The first contact element  608  is then coupled to the first spring  620  within the extension  408 . The second contact element  610  is coupled to the second spring  622  within the extension  408 . The third contact element  612  is coupled to the third spring  624  within the extension  408 . 
   In order to complete the circuit, each of the contacts must contact an electrical lead. The first spring  620  is coupled to the first lead  614 . The second spring  622  is coupled to the second lead  616 , and the third spring is coupled to the third lead  624 . Hence, continuity exists between each of the leads and an electrical lead, so that a power circuit can be completed. 
   The contact element, too, must also be in a position to contact other conductive material, such as a conductive ring. The extension  408  is placed in the notch of the rotatable second part  404  and coupled to the base. The extension  408  is positioned relative to the rotatable second part  404  so that the contact elements  608 ,  610 , and  612  protrude into a cylindrical cavity created by the rotatable second part  404  and extension  408 . 
   The functionality of the rotatable joint  304  of  FIG. 4  is augmented by its combination into the lower assembly  600  of  FIG. 6  and the rotatable first part  412  of  FIG. 5 . The conductive rings  506 ,  508 , and  510 , and the attached assembly, are inserted into the cylindrical cavity created by the rotatable second part  404  and the extension  408 . Power is carried through the rotatable first part  412  to the conductive rings  506 ,  508 , and  510 . Each of the conductive rings  506 ,  508 , and  510  is then in slidable electrical contact with one of the contact elements  608 ,  610 , and  612 . Therefore, power can be transferred through the rotatable pitch assembly at any azimuthal position of the rotatable first part  412 . Further, 360 degrees of rotation is possible about axis  420  and such rotation can be continued in the same direction an indefinite number of times without requiring untwisting of the power cord. 
   Referring to  FIGS. 7A and 7B  of the drawings, the reference numeral generally designates an assembly where the rotatable joint couples a horizontal arm and a light together. The assembly  700  comprises a horizontal arm  106 , a rotatable first part  412 , a rotatable second part  404 , a extension  408 , a light  702 , a pitch axle  414 , and a power cord  110 . 
   The horizontal arm  106  is coupled to the rotatable first part  412  by way of the axis  414 . That way, the pitch of the support assembly (and light) can be varied with respect to the horizontal arm  106 . The rotatable first part  412  is then coupled to the rotatable second part  404  and extension  408 . The rotatable second part  404  and the extension  408  are then coupled to the light  702  by means of attachment plate  402 . 
   Power is then transferred to the light  702  from the power cord. The power is first delivered to the rotatable first part  412  through the power cord  110 . The rotatable first part  412 , the rotatable second part  404 , and the extension  408  comprise the rotatable joint that transfers power. Power from the rotatable joint is transferred to a first lead  614 , a second lead  616 , and a third lead  618 , which correspond to the hot line, the return line and the ground line that are normally associated with convention alternating current power transfer. The leads  616 ,  618 , and  724  are then coupled to a power delivery mechanism  724 , which typically comprises a transformer and several other components. The power delivery mechanism  724  then provides the proper voltage and current to the light bulb  716 . The light bulb  716  is typically a cylindrical florescent bulb. 
   It should be noted that, although conductive rings  506 ,  508  and  510  are shown on the rotatable first part  412  and the contacts  608 ,  610  and  612  on rotatable second part  404 , the conductive rings  506 ,  508  and  510  could also be disposed on rotatable second part  404  and the contacts  608 ,  610  and  612  disposed on the rotatable first part  412 . 
   As can be seen in  FIGS. 7A and 7B , the rotatable second part  404  of the rotatable joint  304  can be angularly twisted about axis  420  back and forth about arc  405  a full 360 degrees in both directions, as well as an unlimited number of rotations in each directions. The support  412  of the rotatable joint  304  can also be angularly repositioned about axle  414  back and forth about arc  407  in a wide range of pitch angles (though not 360 degrees). 
   As can be seen in  FIGS. 3 and 7A , rotation of pitch joint  414  about axle  414  will cause minimal bending of cord  110 , despite large angular movements of support  412  about axle  414 . This permits multiple repositioning of the inspection light during body work without wearing, fraying or other damage of the electrical power cord and with greatly reduced risks of short circuits or electrocution. 
   It is understood that the present invention can take many forms and embodiments. Accordingly, several variations may be made in the foregoing without departing from the spirit or the scope of the invention. The capabilities outlined herein allow for the possibility of a variety of programming models. This disclosure should not be read as preferring any particular programming model, but is instead directed to the underlying mechanisms on which these programming models can be built. 
   Having thus described the present invention by reference to certain of its preferred embodiments, it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that a wide range of variations, modifications, changes, and substitutions are contemplated in the foregoing disclosure and, in some instances, some features of the present invention may be employed without a corresponding use of the other features. Many such variations and modifications may be considered desirable by those skilled in the art based upon a review of the foregoing description of preferred embodiments. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention.