Patent Publication Number: US-2022219291-A1

Title: Electrically isolated tool with failsafe coating

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. application Ser. No. 17/600,902 filed on Oct. 1, 2021 which is the U.S. national phase application of international application number PCT/US2020/018041 filed on Feb. 13, 2020 which claims priority to U.S. provisional application No. 62/828,670 filed Apr. 3, 2019, the entire contents of which are hereby incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     Example embodiments generally relate to driving devices such as socket tools, bit holders and other fastener driving components. In particular, example embodiments relate to an electrically isolated coupling and a failsafe coating that can be used with such driving components to enable safe use in environments where work occurs around electrically charged components. 
     BACKGROUND 
     Socket tools, such as socket wrenches, are familiar tools for fastening nuts and other drivable components or fasteners. The sockets of these tools are generally removable heads that interface with the socket wrench on one side and interface with one of various different sizes of nut or other fastener on the other side. Because high torque is often applied through these tools, and high strength and durability is desirable, the sockets are traditionally made of a metallic material such as iron or steel. However, metallic materials can also corrode or create spark or shock hazards when used around electrically powered equipment. 
     Although it may be possible to coat a metallic socket in a material that is non-conductive, such material is typically not suitable for coverage of either the driving end of the socket (i.e., the end that interfaces with the wrench) or the driven end of the socket (i.e., the end that interfaces with the nut or other fastener being tightened by the socket wrench) directly contacting the driving tool or fastener. In this regard, the high torque and repeated contact with metallic components would tend to wear such materials away over time and degrade the performance of the tool. Thus, it is most likely that the ends of the socket directly contacting the driving tool or fastener would remain (or revert to) exposed metallic surfaces resulting in the socket potentially conducting electricity and becoming a shock or spark hazard. 
     Accordingly, a number of designs had been provided for electrical isolation of sockets. However, these designs often simply provide an isolation material between opposing metal portions of the drive and driven ends. This can provide one or more weak points where the isolation material is unsupported and can fail under high torque loads. If the isolation material fails during a tightening operation, it is possible that electrical contact can be initiated between the drive and driven ends, thereby endangering personnel or equipment. As such, further isolation may be desirable. 
     BRIEF SUMMARY OF SOME EXAMPLES 
     Some example embodiments may enable the provision of a coupling device that includes a driven end and driving end that are electrically isolated via an isolation material. However, example embodiments may further include a failsafe coating that continues isolation of such parts even if contact is made if the isolation material should happen to fail. The coupling device may be used as an adaptor for driving any selected socket, bit holder, and/or the like, even if such socket/bit holder is not electrically isolated. Given that the coupling device employs electrical isolation, existing (non-electrically isolated) fastener driving components can be used in proximity to electrical components based on the isolation provided by the coupling device. 
     In an example embodiment, an electrically isolated coupler is provided. The electrically isolated coupler may include a drive body, a driven body, an insulating member and a isolation coating. The drive body may be made of first metallic material and have a drive end configured to interface with a fastening component. The drive body may include a first interface portion and the driven body may include a second interface portion. The driven body may be made of a second metallic material and have a driven end configured to interface with a driving tool. The insulating member may be molded to fit between the drive body and the driven body to electrically isolate the drive body and the driven body from each other. The isolation coating may be disposed on a surface of the first interface portion or the second interface portion that contacts the insulating member and faces the second interface portion or the first interface portion, respectively. The isolation coating may also include a material that adheres to metal and has a dielectric strength of greater than about 10 kV. 
     In another example embodiment, an electrically isolated socket may be provided. The electrically isolated socket may include a drive body, a driven body, an insulating member and a isolation coating. The drive body may be made of first metallic material and have a hex shaped socket. The drive body may include a first interface portion and the driven body may include a second interface portion. The driven body may be made of a second metallic material and have a driven end configured to interface with a driving tool. The insulating member may be molded to fit between the drive body and the driven body to electrically isolate the drive body and the driven body from each other. The isolation coating may be disposed on a surface of the first interface portion or the second interface portion that contacts the insulating member and faces the second interface portion or the first interface portion, respectively. The isolation coating may also include a material that adheres to metal and has a dielectric strength of greater than about 10 kV. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
       Having thus described some example embodiments in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein: 
         FIG. 1A  is a front perspective view of an electrically isolated coupler according to an example embodiment; 
         FIG. 1B  is an exploded front perspective view of the electrically isolated coupler according to an example embodiment; 
         FIG. 1C  is a cross section view of the electrically isolated coupler according to an example embodiment; 
         FIG. 2A  is an exploded perspective view of an alternative assembled structure of an electrically isolated coupler according to an example embodiment; 
         FIG. 2B  is an assembled side view of the electrically isolated coupler of  FIG. 2A  according to an example embodiment; 
         FIG. 2C  is a cross section view of the electrically isolated coupler taken along line A-A′ of  FIG. 2B ; 
         FIG. 3  is a cross section view of an alternate electrically isolated coupler according to an example embodiment; and 
         FIG. 4  illustrates a perspective view of an electrically isolated socket according to an example embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Some example embodiments now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all example embodiments are shown. Indeed, the examples described and pictured herein should not be construed as being limiting as to the scope, applicability or configuration of the present disclosure. Rather, these example embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like reference numerals refer to like elements throughout. Furthermore, as used herein, the term “or” is to be interpreted as a logical operator that results in true whenever one or more of its operands are true. As used herein, operable coupling should be understood to relate to direct or indirect connection that, in either case, enables functional interconnection of components that are operably coupled to each other. 
     As indicated above, some example embodiments may relate to the provision of electrically isolated fastener driving tools that can be used in proximity to powered components or components that have an electrical charge. In some cases, the user can safely work on or around such components or systems without having to de-energize the system. The electrical isolation provided may eliminate the risk of surge currents traveling from a fastener to a socket tool, bit driver or other fastener driving tool (such as a socket wrench or a power tool that drives sockets, bits, etc.). Particularly for power tools that include electronic components that log data about power tool usage, the isolated coupling of example embodiments can protect valuable computer data such as recorded torque information on fasteners and run-down count history for estimating power tool life. 
     Example embodiments may provide a secondary electrical isolation barrier in case the primary electrical isolation barrier should fail. In this regard, as will be seen below, there are a number of specific structures that can be employed in connection with the general isolation strategy of physically separating the drive end and driven end of a coupler or adapter into a drive body and driven body, respectively, that have isolation material (e.g., non-conductive or insulating material such as, for example, nylon, molding compound, glass-fiber reinforced material, plastic composite material, etc.) positioned therebetween to prevent contact. Some of those strategies involve aligning isolated surfaces relative to one another so that there is overlap along the axial direction of surfaces on the drive body with corresponding surfaces of the driven body. These strategies can take any of a vast number of different specific forms for creating and aligning the surfaces. However, other strategies may provide physical separation between the drive body and driven body of at least a given amount that is determined based on the rated voltage for isolation and, particularly for higher voltage ratings, the resulting structures may not have any overlap in the axial direction. 
     In either case (i.e., designs permitting axial overlap or designs with no axial overlap), torque is transferred at least in part through the isolation material, and significant stresses can be taken in the isolation material. To the extent the torque is high enough to cause a failure in the integrity (either complete or partial) of the isolation material, the insulating characteristics of the coupler or adapter can be lost or reduced. This can leave personnel and equipment exposed to the possibility of electric shock during that failure event, particularly (but not necessarily only) if contact is made between the driven body and the drive body. 
     One way to provide a secondary protection means in case the isolation material should fail would be to utilize two different or distinct insulating layers. One layer could be less susceptible to cracking or breaking than the other so that when the first material cracks, the other does not. Although this method might provide enhanced protection, it comes with some drawbacks. In this regard, for example, the addition of a second layer of isolation material can substantially increase the space between the driven body and the drive body and reduce the amount of torque that the resulting coupler or adapter can transfer (for a given length) or increase the length of the coupler or adapter (for a given torque rating) to the point where its usefulness can be limited in certain contexts. 
     Accordingly, example embodiments provide an improved option for secondary protection. In this regard, for example, some example embodiments may provide for the use of an isolation coating that is applied to the surfaces of either or both of the drive body and the driven body that face each other. The isolation coating can be accomplished, for example, by dipping or plating the drive body and/or the driven body such that at least one of the surfaces that face each other is provided with a very thin layer of additional electrical isolation. Due to the thin nature of the coating material, the disadvantages in terms of torque rating reduction or tool lengthening that were described above can be avoided. Meanwhile, an effective method of secondary protection can be provided such that the coupler or adapter is configured to failsafe in the event of a material failure in the isolation material. Some structures that can employ example embodiments will now be described below by way of example and not limitation. 
       FIG. 1A  illustrates a perspective view of an electrically isolated adapter  100  according to an example embodiment, and  FIG. 1B  illustrates an exploded perspective view of the adapter  100 .  FIG. 1C  illustrates a cross section view of the adapter  100  taken along the axis of rotation of the adapter (which is also the longitudinal axis of the adapter  100 ). As such,  FIGS. 1A-1C  illustrate various views of a drive body  110  and driven body  120  of the adapter  100 , which can be formed by injection of insulating material between the drive body  110  and the driven body  120 . Thus, in addition to the drive body  110  and the driven body  120 , the adapter  100  may include an isolation assembly  130  that is configured to separate the drive body  110  from the driven body  120  and also cover substantially all of the lateral edges of the driven body  120 . 
     The drive body  110  and driven body  120  may each be made of steel or another rigid metallic material. Steel or other rigid metals generally have a low resistance to electrical current passing therethrough. The drive body  110  and the driven body  120  may be designed such that, when assembled into the adapter  100 , the drive body  110  and the driven body  120  do not contact each other. The drive body  110  and the driven body  120  may be oriented such that a drive end  112  of the drive body  110  and a driven end  122  of the driven body  120  face in opposite directions. Axial centerlines of each of the drive body  110  and the driven body  120  are aligned with each other and with a longitudinal centerline of the adapter  100 . 
     The drive body  110  may include a drive head  140 , which faces away from the driven body  120  and protrudes out of the isolation assembly  130 . The drive head  140  may be configured to interface with a socket, a fastener, or any other component having a receiving opening that is complementary to the shape of the drive head  140 . In this example, the drive head  140  is a drive square. However, other shapes for the drive head  140  are also possible, and in some cases, the drive head  140  could be replaced with a socket. In some embodiments, a ball plunger may be disposed on a lateral side of the drive head  140  to engage with a ball detent disposed on a socket or other component. 
     The drive body  110  may also include drive body shaft  142  that may be configured to extend rearward from the drive head  140 . Both the drive head  140  and the drive body shaft  142  may share a common axis  144 , which is also the rotational and longitudinal axis of the drive body  110  and the adapter  100 , when the adapter  100  is fully assembled. As can be appreciated from  FIG. 1B , the drive body shaft  142  may be a splined shaft. As such, for example, a plurality of splines  146  (e.g., longitudinally extending ridges, protrusions or teeth) may extend parallel to the common axis  144  along a periphery of the drive body shaft  142 . Between each of the splines  146 , a longitudinally extending trench  148  may be formed. Any desirable number of splines  146  and trenches  148  could be employed in example embodiments. 
     The splines  146  may extend radially outward from a cylindrical core of the drive body shaft  142 . The cylindrical core portion of the drive body shaft  142  may have a diameter that is about equal to a diagonal length between opposing corners of the drive head  140 . The splines  146  may extend away from the cylindrical core portion by between about 5% and 25% of the diameter of the cylindrical core portion of the drive body shaft  142 , and the diagonal length between opposing corners of the drive head  140 . Thus, the diameter of the drive body shaft  142  may be no more than 50% larger than the diagonal length between opposing corners of the drive head  140  (and in some cases as little as 10% larger). In this example, the splines  146  and trenches  148  have a substantially sinusoidal shape when viewed in cross section. However, the splines  146  and trenches  148  could alternatively have sharper edges, if desired. 
     In an example embodiment, the drive body shaft  142  may be dipped, plated or otherwise treated in order to form a isolation coating  149  over all external surfaces of the splines  146  and the trenches  148 . In other words, all external surfaces of the drive body shaft  142  may have the isolation coating  149  applied thereto. The isolation coating  149  is therefore applied to all surfaces of the drive body  110  that face or are adjacent to a corresponding surface of the driven body  120 . Of note, the isolation coating  149  is represented in the cross section view of  FIG. 1C , but the representation thereof is not intended to be to scale since the isolation coating  149  is kept very thin. For example, a thickness of the isolation coating  149  may be between about one to ten thousandths of an inch. The isolation coating  149  may be made of a material that has a relatively high dielectric strength (e.g., greater than 10 kV), and yet adheres well to steel or other metallic materials to enable the metallic material to be coated thereby. Thus, for example, the isolation coating  149  may be made of a ceramic material in some cases. 
     As shown in  FIGS. 1B and 1C , the driven body  120  may take the form of a cylinder that has been hollowed out to at least some degree to form a drive body receiver  150 . The drive body receiver  150  may be formed between sidewalls  152  (which could be considered a single tubular sidewall) of the driven body  120  that define the external peripheral edges of the driven body  120  and radially bound the drive body receiver  150 . The sidewalls  152  may extend parallel to the common axis  144  away from a base portion  153 . The sidewalls  152  may have longitudinally extending ridges  154  that extend inwardly from the sidewalls  152  toward the common axis  144 . The ridges  154  may be separated from each other by longitudinally extending recesses  156 . The ridges  154  and recesses  156  may be equal in number to the number of splines  146  and trenches  148  of the drive body  110  and may be formed to be substantially complementary thereto. However, the diameter of the drive body receiver  150  may be larger than the diameter of the drive body shaft  142  so that the ridges  154  remain spaced apart from corresponding portions of the trenches  148  and the splines  146  remain spaced apart from corresponding portions of the recesses  156 . 
     In some cases, the driven body  120  may further include an annular groove  160  that may include a receiver  162  formed in the base portion  153 . In this regard, the annular groove  160  may be formed around a periphery of the base portion  153 . The annular groove  160  and/or the receiver  162  may be used for facilitating affixing the driven body  120  to the power tool or wrench that is used to drive the adapter  100  via passing of a pin through the receiver  162 , or via a ball plunger being inserted into the receiver  162  as described above from a drive head of the power tool or wrench. Thus, the receiver  162  may extend through the driven body  120  (at the annular groove  160 ) substantially perpendicular to the common axis  144  of the adapter  100 . The annular groove  160  may be provided proximate to (but spaced apart from) the driven end  122 . A drive receiver  163  may also be formed in the driven end  122  to receive the drive head of the power tool or wrench that operably couples to the adapter  100 . In other words, the drive receiver  163  may be formed through the base portion  153  along the common axis  144 . 
     When the drive body  110  is inserted into the driven body  120  (as shown in  FIGS. 1A and 1C ), an inside surface of the sidewalls  152  may appear corrugated and complementary to an outside surface of the drive body shaft  142 , which also appears corrugated, but spaced apart from the sidewalls  152  by a gap. The drive body  110  and the driven body  120  may be maintained spaced apart from each other in this manner (such that no portion of either touches any portion of the other) while an insulating material (e.g., nylon, rubber, plastic, resin, or other such materials) is injected therebetween as part of an injection molding operation. The insulating material has a high resistance to electrical current passing therethrough; in one embodiment the resistance to electrical current of the insulating material is several orders of magnitude higher than the resistance to electrical current of stainless steel. The insulating material may fill the gap and define an insulating member  172  in the form of a corrugated or fluted separator in this case. The insulating member  172  may separate the sidewalls  152  from the drive body shaft  142 , and thereby also separate the splines  146  and trenches  148  from the recesses  156  and ridges  154 , respectively. The insulating material of the insulating member  172  may entirely fill the gap and any other spaces between the drive body  110  and the driven body  120  within the drive body receiver  150 , and may also be molded over the outside surface of the sidewalls  152  of the driven body  120  and the drive end  112  by outer molding  174 . The outer molding  174  and the insulating member may combine to form the isolation assembly  130 . The driven end  122  could also be covered, although some embodiments (including this example) may leave the driven end  122  uncovered. The insulating material may, once cured, form the isolation assembly  130  in order to leave only the metal of the drive head  140  and the drive receiver  163  area exposed. Although outside the scope of the present disclosure, additional components may be provided and/or designed to enable retention of the drive body  110  and driven body  120  relative to each other during the injection molding process. Accordingly, the drive body  110  and the driven body  120  may be clamped effectively in an injection molding machine during the injection molding process to ensure that the pressure stays balanced and the respective parts do not move during the injection process and result in uneven thickness of the insulating material. 
     The adjacent surfaces of the drive body  110  and the driven body  120  may transfer torque therebetween through the insulating member  172  (and also through the isolation coating  149 ). In this regard, as a torque is applied through the driven body  120 , the sidewalls  152  are urged to rotate about the common axis  144 . The torque is transferred to the splines  146  and trenches  148  of the drive body  110  from the recesses  156  and ridges  154 , respectively, through the insulating member  172  in order to also urge the drive body  110  and the drive head  140  to turn. The drive head  140  passes the torque on to the fastener, socket, or other device to which the drive body  110  may be attached. 
     If the torque applied is sufficient to exceed the sheer strength of the insulating member  172 , the insulating member  172  may fail to properly separate the splines  146  and trenches  148  of the drive body  110  from the recesses  156  and ridges  154 , respectively, at one or more locations. As such, at least one spline  146  of the drive body  110  may be enabled to move toward contact with a corresponding at least one ridge  154  of the driven body  120 . However, due to the presence of the isolation coating  149 , the electrical isolation characteristics of the adapter  100  may be maintained during this failure event so that the instantaneous contact between at least one spline  146  of the drive body  110  and the corresponding at least one ridge  154  of the driven body  120  does not allow current to pass from the drive body  110  to the driven body  120 . 
     Although not required, in some cases, the recesses  156  and ridges  154  of the driven body  120  may also be coated with the isolation coating  149 ′ as shown in dashed lines in  FIG. 1C . Thus, both the drive body  110  and the driven body  120  could employ an instance of isolation coating. However, it should be appreciated that in some embodiments, only one body may need such coating. When only one body is coated, the body that is most easily coated may be the one that is selected (e.g., the drive body  110  in this example). It should therefore be appreciated that either or both of the surfaces that face each other (and overlap each other in the axial direction in this example) may be provided with the isolation coating  149 / 149 ′. Moreover, the coatings can be applied in connection with other specific structures. 
       FIG. 2 , which is defined by  FIGS. 2A, 2B, and 2C , illustrates an alternative structure of an electrically isolated coupler (or adaptor) having a secondary isolation barrier provided by a isolation coating according to an example embodiment.  FIG. 2A  is an exploded perspective view, and  FIG. 2B  is a side view of the assembled structure of  FIG. 2A .  FIG. 2C  is a cross sectional view taken along a line perpendicular to the longitudinal axis of the coupler of  FIGS. 2A and 2B  along line A-A′ of  FIG. 2B . As shown in  FIG. 2 , the electrically isolated coupler  200  may include a driven body  220  and a drive body  210 . The driven body  220  and drive body  210  do not contact each other due to the presence of insulating member  230  therebetween. The insulating member  230  fits between an interface portion of the driven body  220  and an interface portion of the drive body  210  where the respective interface portions overlap each other along the longitudinal axis of the electrically isolated coupler  200  at least at portions thereof that face each other as they extend along the axial direction. 
     As can be seen in  FIG. 2 , a drive mating structure  226  of the driven body  220  is provided at a separate axially extended portion of the drive body  220  from the interface portion. Although the overall length of the electrically isolated coupler  200  may be increased due to this design, it should be noted that the removal of the drive mating structure  226  from the interface portion  224  may create the opportunity for increased design flexibility relative to the structure of the interface portion  224  and the insulating member  230 . 
     In the example of  FIG. 2 , the interface portion of the driven body  220  and the interface portion of the drive body  210  substantially mirror each other. In this regard, the interface portion of the driven body  220  is defined by protruding members  260  that are substantially shaped as two axially extending quarter circles in opposite quadrants. Meanwhile, the interface portion of the drive body  210  is also defined by protruding members  250  that are substantially shaped as two axially extending quarter circles in opposite quadrants. Moreover, the protruding members  260  of the interface portion of the driven body  220  are in opposing quadrants relative to the protruding members  250  of the interface portion of the drive body  210 . 
     As in the prior example, the drive body  210  and the driven body  220  are separated from each other by an isolation material that forms the insulating member  230 . In particular, the insulating member  230  separates the interface portion of the driven body  220  and the interface portion of the drive body  210  from each other in both radial and axial directions to provide a complete electrical isolation therebetween. However, the insulating member  230  is also provided between axially extending faces of each of the interface portion of the driven body  220  and the interface portion of the drive body  210  to allow such faces to apply torque to both sides of the insulating member  230  between such faces. Accordingly, there is no axially extending portion of the insulating member  230  that is not supported on opposing sides thereof by respective ones of the interface portion of the driven body  220  and the interface portion of the drive body  210 . Additionally, there is no cross section of the electrically isolated coupler  200  that could be taken anywhere along the axial length of the electrically isolated coupler  200  that would include only the material of the insulating member  230 . As such, no weak point exists at which the material of the insulating member  230  alone could fail to damage or destroy the electrically isolated coupler  200 . 
     As discussed above, the insulating member  230  may be formed from an insulating material (e.g., nylon, rubber, plastic, resin, or other such materials) that is injected between the drive body  210  and driven body  220  as part of an injection molding operation. In the example of  FIG. 2 , the insulating member  230  is therefore defined by axially extending portions  232  that separate the protruding members  250  and  260  from each other along their parallel extending faces that extend in the axial direction. The insulating member  230  also includes radially extending portions  234  and  236  that generally extend in a radial direction to separate parallel faces of distal ends of the protruding members  250  and  260  from corresponding portions of the drive body  210  and the driven body  220 , respectively. 
     As discussed above, failure of the insulating member  230  due to excessive torque may enable opposing faces (particularly axially extending faces) of the protruding members  250  and  260  to contact each other. Accordingly, at least one (and perhaps both) of the protruding members  250  and  260  may be coated with a isolation coating as described above. In  FIG. 2B , the isolation coating  270  is formed at axially extending faces of the protruding member  260  that face the corresponding axially extending faces of protruding member  250 . Coating just the protruding member  260  in this manner may be sufficient to provide a secondary mode of protection in case of the failure of the insulating member  230  and contact (or a reduction in distance) the protruding members  250  that enables current (or an electrical discharge) to pass therebetween. However, it may also be possible (or even desirable) to also coat the other protruding member  250  as shown by isolation coating  272 . Moreover, the isolation coating  272  could be used instead of the isolation coating  270  in some cases. 
     In one particular example, only axially extending faces of the protruding members  250  and  260  (and even then, only necessarily one of such faces) may be covered with the isolation coating  270  or  272 . However, in other cases, the radially extending faces of either or both of the protruding members  250  and  260  (and respective opposing portions of the drive member and driven member  210  and  220 ) may also include isolation coatings  274 . Thus, either all faces of the drive member  210  and driven member  220  that are adjacent to each other may have a isolation coating provided therebetween, or only the axially extending faces may have such coating. Additionally, either one or both of the drive member  210  and the driven member  220  may be coated. 
     Thus, it should be appreciated that a number of different designs may be included for the insulating member, the interface portions of the drive body and the driven body, and the specific placement of the isolation coating. However, all such designs may generally provide that any cross section through the axially extending portions of the adapter or coupler where the drive body is adjacent to the driven body would include portions of both the insulating member and at least one (and sometimes two) isolation coating(s) between the interface portion of the driven body and the interface portion of the drive body. This, of course, applies when there is overlap of the drive body and the driven body along the axial direction. However, example embodiments can also be practices when no such overlap occurs.  FIG. 3  illustrates a cross section view of an adapter  300  taken along the axis or longitudinal centerline of the adapter  300 . As shown in  FIG. 3 , the drive body  310  is separated from the driven body  320  by an insulating member  330  as discussed above. However, there is no axial overlap of the drive body  310  and the driven body  320 . Thus, a cross section can be taken through the adapter  300  perpendicular to the axis, and pass only through the insulating member  330 . This may be advantageous for very high voltage applications where a gap between the drive body  310  and the driven body  320  must be relatively high. 
     As shown in  FIG. 3 , the drive body  310  and the driven body  320  may have corresponding interface portions (e.g., in the form of castle teeth that extend toward each other) that do not overlap axially. However, these interface portions may be considered to be adjacent to each other across the insulating member  330  (or facing each other on opposing sides of the insulating member  330 ). Accordingly, one or both of these interface portions may be provided with a isolation coating  340  or  342  as shown in  FIG. 3 . Thereafter, an overmold  350  may be formed around the structure to encapsulate the drive body  310  and the driven body  320  along with the insulating member  330 . The overmold  350  may also render the insulating member  330  and the isolation coating(s)  340 / 342  inaccessible to the operator and other external agents or components. Accordingly, the structural integrity of the insulating member  330  and the isolation coating(s)  340 / 342  may be preserved by the overmold  350  thereby increasing the useful life of the adapter  300 . 
     Although the examples of  FIGS. 1, 2 and 3  generally correspond to an electrically isolated coupler that acts as an adapter to receive a male drive square at one end (i.e., the driven end) and convert to an isolated male drive square at the other end (i.e., at the drive end), other structures are also possible. In this regard, for example, the drive body could be replaced with an alternate drive body  410  that has a drive mating  415  formed as a hex socket in order to provide an electrically isolated socket  400  of a desirable size. The driven body  420  may otherwise be similar to the driven bodies described above, and the interface portions of the drive body  410  and driven body  420  may also be shaped in any of the ways described herein and other suitable ways. The insulating member  430  may be formed as described above, and function similarly as well. Similarly, a isolation coating  440  or  442  may be provided on either one or both of the interface portions of the drive body  410  and the driven body  420 . 
     In some cases, the molding process (for the insulating member and/or the overmold or sleeve) may work to axially bind the drive body and the driven body together. However, in some cases, structural features may be provided on the interface portions of either or both of the driven body and the drive body to further facilitate retention of the entire assembly in contact with each other. 
     Accordingly, an electrically isolated coupler of an example embodiment may include a drive body, a driven body, an insulating member and a isolation coating. The drive body may be made of first metallic material and have a drive end configured to interface with a fastening component. The drive body may include a first interface portion and the driven body may include a second interface portion. The driven body may be made of a second metallic material and have a driven end configured to interface with a driving tool. The insulating member may be molded to fit between the drive body and the driven body to electrically isolate the drive body and the driven body from each other. The isolation coating may be disposed on a surface of the first interface portion or the second interface portion that contacts the insulating member and faces the second interface portion or the first interface portion, respectively. The isolation coating may also include a material that adheres to metal and has a dielectric strength of greater than about  10  kV. In some cases, the coupler could instead be configured as a socket when the drive end includes a hex shaped receiver. 
     In some embodiments, the coupler (or a socket) may include additional, optional features, and/or the features described above may be modified or augmented. Some examples of modifications, optional features and augmentations are described below. It should be appreciated that the modifications, optional features and augmentations may each be added alone, or they may be added cumulatively in any desirable combination. In an example embodiment, the first interface portion may include at least one axially extending portion that extends toward the driven body, and the second interface portion may include at least one axially extending portion that extends toward the drive body. The isolation coating may be applied at least to an axially extending face of the first interface portion or the second interface portion. In some cases, the isolation coating may be applied to each of the first interface portion and the second interface portion. In an example embodiment, the isolation coating may be applied both to axially extending portions and radially extending portions of each of the first interface portion and the second interface portion. In some cases, the isolation coating may be applied only to axially extending portions of each of the first interface portion and the second interface portion. In an example embodiment, the first interface portion and the second interface portion may overlap and face each other along an axial direction. In some cases, the electrically isolated coupler further includes a sleeve disposed around radial edges of the drive body, the driven body, the insulating member and the isolation coating to prevent access to the insulating member and the isolation coating. In an example embodiment, the isolation coating may include a ceramic material. In some cases, the isolation coating may have a thickness of between about one and ten thousandths of an inch, or even between about two and seven thousandths of an inch. In an example embodiment, the isolation coating may be deposited on the first interface portion or the second interface portion by dipping the first interface portion or the second interface portion in a non-conductive material that adheres to metal. In some cases, the isolation coating may be deposited on the first interface portion or the second interface portion by plating a non-conductive material onto the first interface portion or the second interface portion. Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Moreover, although the foregoing descriptions and the associated drawings describe exemplary embodiments in the context of certain exemplary combinations of elements and/or functions, it should be appreciated that different combinations of elements and/or functions may be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, different combinations of elements and/or functions than those explicitly described above are also contemplated as may be set forth in some of the appended claims. In cases where advantages, benefits or solutions to problems are described herein, it should be appreciated that such advantages, benefits and/or solutions may be applicable to some example embodiments, but not necessarily all example embodiments. Thus, any advantages, benefits or solutions described herein should not be thought of as being critical, required or essential to all embodiments or to that which is claimed herein. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.