Patent Publication Number: US-8979559-B2

Title: Lockout tagout plug sleeve

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. §119 to U.S. Provisional Patent Application Ser. No. 61/570,537, titled “Lockout Tagout Plug Sleeve” and filed on Dec. 14, 2011, the entire contents of which are hereby incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     Embodiments of lockout tagout plug sleeves relate generally to isolating a power source, and more particularly to systems, methods, and devices for facilitating a lockout tagout tag on a high amperage electrical connector. 
     BACKGROUND 
     A plug sleeve can be used to protect one or more pins of an electrical plug connector. The plug sleeve can be mechanically coupled to the electrical plug connector and have one or more of a number of features. For example, a plug sleeve can have a slot to help align the plug connector with a corresponding receptacle that receives the plug connector. 
     The use of lockout tagout procedures helps ensure safe operations and maintenance of power equipment. A lockout tagout on a sleeve for a high amperage electrical plug helps ensure that the plug cannot be engaged in its corresponding receptacle during maintenance and repair of associated equipment. The location of a lockout tagout should be visible and convenient to access. 
     SUMMARY 
     In general, in one aspect, the disclosure relates to a lockout tagout plug sleeve for an electrical connector. The lockout tagout plug sleeve can include a cylindrical body having at least one wall having a length between a first end and a second end, where the at least one wall forms a cavity, and where the cavity receives, toward the second end, an electrical plug assembly. The lockout tagout plug sleeve can also include a polarizing slot disposed on an outer surface of the at least one wall along the length of the at least one wall. The lockout tagout plug sleeve can further include a lockout tagout hole configured to receive a lockout tagout tag, where the lockout tagout hole traverses the at least one wall at a first distance from the first end and is oriented relative to the polarizing slot and the first end. 
     In another aspect, the disclosure can generally relate to an electrical connector. The electrical connector can include a plug assembly having a plurality of pins. The electrical connector can also include a lockout tagout plug sleeve mechanically coupled to the plug assembly. The lockout tagout plug sleeve can include a cylindrical body having at least one wall having a length between a first end and a second end, where the at least one wall forms a cavity, and where the cavity receives, toward the second end, the plurality of pins. The lockout tagout plug sleeve can also include a polarizing slot disposed on the outer surface of the at least one wall. The lockout tagout plug sleeve can further include a lockout tagout hole configured to receive a lockout tagout tag, where the lockout tagout hole traverses the at least one wall at a distance from the first end and is oriented relative to the polarizing slot and the first end. 
     These and other aspects, objects, features, and embodiments will be apparent from the following description and the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings illustrate only example embodiments of lockout tagout plug sleeves and are therefore not to be considered limiting of its scope, as the lockout tagout plug sleeves may admit to other equally effective embodiments. The elements and features shown in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the example embodiments. Additionally, certain dimensions or positionings may be exaggerated to help visually convey such principles. In the drawings, reference numerals designate like or corresponding, but not necessarily identical, elements. 
         FIG. 1  shows a lockout tagout plug sleeve in accordance with one or more example embodiments. 
         FIGS. 2A and 2B  show different views of a lockout tagout plug sleeve in accordance with one or more example embodiments. 
         FIG. 3  shows an example connector that includes a lockout tagout plug sleeve in accordance with one or more example embodiments. 
         FIG. 4  shows a cross-sectional perspective side view of an example electrical connector system that includes a lockout tagout plug sleeve in accordance with one or more example embodiments. 
     
    
    
     DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS 
     Example embodiments of lockout tagout plug sleeves will now be described in detail with reference to the accompanying figures. Like, but not necessarily the same or identical, elements in the various figures are denoted by like reference numerals for consistency. In the following detailed description of the example embodiments, numerous specific details are set forth in order to provide a more thorough understanding of the disclosure herein. However, it will be apparent to one of ordinary skill in the art that the example embodiments herein may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description. As used herein, a length, a width, and height can each generally be described as lateral directions. 
     Embodiments of lockout tagout plug sleeves are directed to high-amperage electrical connectors that are unplugged from its corresponding receptacle in order to perform maintenance and/or repair on associated equipment. In one or more example embodiments, a lockout tagout plug sleeve includes a lockout tagout hole that traverses at least one side of a cylindrical body of the sleeve. The embodiments described herein may provide several advantages, including but not limited to easier access to secure and unsecure a lockout tagout tag, less likelihood of causing damage to portions of the electrical plug when securing and unsecuring a lockout tagout tag, and easy visibility of a lockout tagout tag that is affixed to a plug through the lockout tagout hole. 
     In addition, example embodiments of lockout tagout plug sleeve configurations may be based on one or more of a number of variables, including but not limited to connector pin configuration, plug size, amperage rating, and conductor size. Further, example embodiments of lockout tagout plug sleeves may be compliant with one or more of a number of standards. One such standard is UL 1686 set by Underwriters Laboratories. Another such standard is CSA C22.2 No. 182.1 set by the Canadian Standards Association. In addition, the lockout tagout plug sleeves described herein may be made of one or more of a number of suitable materials, including but not limited to metal. Example embodiments may be directed to metal (not plastic) lockout tagout plug sleeves that meet the standards set forth in UL 1686, CSA C22.2 No. 182.1, and/or any other suitable standard. 
     Example embodiments of lockout tagout plug sleeves now will be described more fully hereinafter with reference to the accompanying drawings, in which example embodiments of lockout tagout plug sleeves are shown. Lockout tagout plug sleeves may, however, be embodied in many different forms and should not be construed as limited to the example embodiments set forth herein; rather, these example embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of lockout tagout plug sleeves to those skilled in the art. Like elements in the various figures are denoted by like reference numerals for consistency. 
       FIG. 1  shows a lockout tagout plug sleeve  100  in accordance with one or more example embodiments. The cylindrical body  110  of the lockout tagout plug sleeve  100  includes at least one wall  111 . The at least one wall  111  can have a first end  116  (also called a sleeve face) that couples to a receptacle (not shown) and a second end  118  that couples to a plug assembly (not shown). The at least one wall  111  of the lockout tagout plug sleeve  100  can be made of an electrically conductive and/or an electrically non-conductive material. 
     In one or more example embodiments, the at least one wall  111  of the cylindrical body  110  is of a finite thickness, and so forms a cavity  130 . The cavity  130  may have a height that is substantially similar to the length of the at least one wall  111 . In addition, or in the alternative, the cavity  130  can have a width that is wide enough to receive one or more connector pins (shown in  FIG. 3  below), which in turn are configured to mate with receiving pin holes of the corresponding receptacle. When multiple connector pins are positioned in the cavity  130  of the cylindrical body  110 , one of the pins may be shorter than the other pins. In such a case, the shorter pin may be a grounding conductor or a grounding pin. 
     The thickness, length, and/or the shape (in this example, circular) of the at least one wall  111  of the cylindrical body  110  (and, thus, the size and shape of the cavity  130 ) may be any suitable thickness, length, and/or shape to allow coupling of the lockout tagout plug sleeve  100  to a corresponding receptacle. Likewise, the size and shape of the first end  116  (here, shown with a beveled edge) and the second end  118  (here, shown with a protruding collar  117  and a ground strap receiver  125 ) may be any suitable size and shape to allow coupling of the lockout tagout plug sleeve  100  to the corresponding receptacle and/or a corresponding plug assembly, respectively. 
     The protruding collar  117  can be an optional feature of the lockout tagout plug sleeve  100 . The protruding collar  117  of the second end  118  can have a larger outer diameter than the outer diameter of the wall  111 . Alternatively, or in addition, the protruding collar  117  of the second end  118  can have a smaller outer diameter than the outer diameter of the wall  111 . The protruding collar  117  can help secure the lockout tagout plug sleeve  100  within the plug assembly by having features (e.g., a larger outer diameter compared to the outer diameter of the wall  111 ) that fit within complementary features of the plug assembly. An example of how the protruding collar  117  secures the lockout tagout plug sleeve  100  to the plug assembly are shown in  FIG. 4  below. 
     In certain example embodiments, the optional ground strap receiver  125  protrudes away from a top side of the second end  118 . The ground strap receiver  125  can have one or more of a number of features that secure a ground strap within the plug assembly. Such features can include, but are not limited to, an aperture, a clip, a clamp, and a slot. When a ground strap of the plug assembly is mechanically coupled to the ground strap receiver  125 , a uniform ground is applied to the lockout tagout plug sleeve  100  and the plug assembly. The ground strap receiver  125  can be made of one or more of a number of electrically conductive materials, which may be the same or different than the material of the at least one wall  111 . 
     Such dimensions of the at least one wall  111 , as well as other features of the lockout tagout sleeve  100 , can be sized to correspond with an appropriate current rating, voltage rating, and/or any other type of rating of the electrical connector. For example, if an electrical connector is rated for 400 Amperes (A), then the dimensions of the lockout tagout sleeve  100  must be suitable to maintain the 400A rating of the electrical connector when the lockout tagout sleeve  100  is mechanically coupled to the electrical plug assembly. 
     In one or more example embodiments, the lockout tagout plug sleeve  100  also includes at least one pair of locking receivers  106  disposed at least on the outer surface of the at least one wall  111  of the cylindrical body  110 . The pair of locking receivers  106  can be disposed along the length of the at least one wall  111  of the cylindrical body  110 . The locking receivers  106  are a type of safety feature. Each of the locking receivers  106  may receive a mating device from the corresponding receptacle and/or plug assembly. The mating device may engage one or both of the pair of locking receivers  106  when the plug assembly and corresponding receptacle are engaged and when current is flowing through the plug assembly and corresponding receptacle. Each locking receiver  106  of the pair of locking receivers may be positioned at some distance from the first end  116  and on opposite sides of the cylindrical body  110 , as shown in  FIG. 1 . The locking receivers  106  may be of any shape, size, and configuration suitable to securely receive the mating devices of the corresponding receptacle and/or plug assembly. In the example embodiment shown in  FIG. 1 , the locking receivers  106  are holes that traverse the wall  111  of the cylindrical body  110 . 
     In one or more example embodiments, the lockout tagout plug sleeve  100  also includes a polarizing slot  114 . The polarizing slot  114  is disposed on the cylindrical body  110  and helps ensure that the plug assembly is properly oriented in order to mate with the corresponding receptacle. The polarizing slot  114  may be any feature on the lockout tagout plug sleeve  100  that allows for a discrete number of orientations of the plug assembly relative to mating with the corresponding receptacle. The polarizing slot  114  of  FIG. 1  is a linear groove disposed along the length (carved into the outer surface, in this example) of the wall  111 . 
     In one or more example embodiments, the lockout tagout plug sleeve  100  also includes a lockout tagout hole  102 . The lockout tagout hole  102  is an aperture that traverses the wall  111  and has dimensions (e.g., shape, width) to receive a lockout tagout tag. A lockout tagout tag can be a physical tag with wording to warn that the device to which the lockout tagout tag is attached is not to be started, used, or otherwise operated. A lockout tagout tag may also be known by other names, including but not limited to a hold tag. The lockout tagout tag includes a feature (e.g., a cable tie, a metal wire, a clamp) that traverses the lockout tagout hole  102 , and that physically attaches to the lockout tagout tag and to itself. 
     In  FIG. 1 , the lockout tagout hole  102  traverses a wall  111  of the cylindrical body  110  at some distance from the first end  116  of the cylindrical body  110 . For example, the lockout tagout hole  102  can be located approximately 0.41 inches from the first end  116 . Such a distance can be measured from an approximate center of the lockout tagout hole  102 , the top of the lockout tagout hole  102 , the bottom of the lockout tagout hole  102 , or any other location on or proximate to the lockout tagout hole  102 . Thus, the lockout tagout hole  102  is configured to receive one or more lockout tagout tags. In this example, the lockout tagout hole  102  is positioned closer to the first end  116  of the cylindrical body  110  when compared to the position of the locking receivers  106  from the first end  116  of the cylindrical body  110 . 
     The lockout tagout hole  102  may traverse the wall  111  of the cylindrical body  110  at one of a number of locations. Specifically, the location of the lockout tagout hole  102  on the lockout tagout plug sleeve  100  can be described with respect to a distance (in a horizontal direction) from the first end  116  and/or with respect to an angle (in a vertical direction) from the polarizing slot  114 . For example, the lockout tagout hole  102  can be positioned approximately 0.5 inches from the first end  116  and approximately 15° to the left of (counterclockwise from) the polarizing slot  114 . In addition, or in the alternative, the position of the lockout tagout hole  102  can be described with respect to one or more other features of the lockout tagout plug sleeve  100 , including but not limited to the second end  118  and the pair of locking receivers  106 . 
     In addition, or in the alternative, the position of the lockout tagout hole  102  on the lockout tagout plug sleeve  100  can be described in one or more other ways. For example, the position of the lockout tagout hole  102  on the lockout tagout plug sleeve  100  can be described in terms of clock position, where in the example embodiment shown in  FIG. 1 , the lockout tagout hole  102  is located (looking from the first end  116 ) at about 11:15, where 12:00 is represented by the polarizing slot  114 . Further, the lockout tagout hole  102  of example  FIG. 1  is located closer to the first end  116  of the cylindrical body  110  than is the pair of locking receivers  106 . In addition, along the length of the wall  111  of the lockout tagout plug sleeve  100 , the lockout tagout hole  102  is not aligned with either of the pair of locking receivers  106 . 
     Any measure of the lockout tagout hole  102  relative to the polarizing slot  114  can be made from the center of the lockout tagout hole  102  and/or the polarizing slot  114 , from the left side of the lockout tagout hole  102  and/or the polarizing slot  114 , the right side of the lockout tagout hole  102  and/or the polarizing slot  114 , and/or any other location on or proximate to the lockout tagout hole  102  and/or the polarizing slot  114 . 
     One or more of a number of features (e.g., dimensions of the at least one wall  111 , orientation of the pair of locking receivers  106 ) of the lockout tagout plug sleeve  100  can be used to categorize a style of the lockout tagout plug sleeve  100 . A number of styles for the lockout tagout plug sleeve  100  can exist and can follow protocols set by industry standards, manufacturer&#39;s specifications, and/or some other entity or protocol. For example, a lockout tagout plug sleeve  100  can have a style  1 , a style  2 , or a style  1  and  2 . 
     The following table provides example dimensions and/or categorizations for various example lockout tagout plug sleeves. The positions listed are the position of the lockout tagout hole  102  relative to the polarizing slot  114 , in degrees, traveling in a clockwise direction from the polarizing slot  114 . 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Example characteristics of a lockout tagout plug sleeve. 
               
            
           
           
               
               
               
               
               
            
               
                 Sleeve Outer 
                   
                 Current 
                   
                 Location 
               
               
                 Diameter 
                   
                 Rating 
                   
                 from first 
               
               
                 (inches) 
                 Position (°)  
                 (A) 
                 Style 
                 end (inches) 
               
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 2.28 
                 315 
                 30 
                 1 
                 0.41 
               
               
                 1.865 
                 112.5 
                 30 
                 1 
                 0.41 
               
               
                 1.865 
                   
                   
                   
                   
               
               
                 1.853 
                 135 
                 30 
                 1 
                 0.41 
               
               
                 2.28 
                 45 
                 30 
                 2 
                 0.41 
               
               
                 1.865 
                 67.5 
                 30 
                 2 
                 0.41 
               
               
                 1.865 
                   
                   
                   
                   
               
               
                 1.854 
                 90 
                 30 
                 2 
                 0.41 
               
               
                 2.546 
                 134.5 
                 60 
                 1 
                 0.41 
               
               
                 2.736 
                   
                   
                   
                   
               
               
                 2.724 
                 180 
                 60 
                 1 
                 0.41 
               
               
                 2.234 
                 135 
                 60 
                 1 
                 0.41 
               
               
                 2.540 + .010 
                   
                   
                   
                   
               
               
                 −.006 
                 45 
                 60 
                 1 
                 0.41 
               
               
                 2.24 
                 67.5 
                 60 
                 2 
                 0.41 
               
               
                 2.546 
                 67.5 
                 60 
                 2 
                 0.41 
               
               
                 2.736 
                   
                   
                   
                   
               
               
                 2.725 
                 135 
                 60 
                 2 
                 0.41 
               
               
                 2.234  
                   
                   
                   
                   
               
               
                 +.005 − .010 
                 90 
                 60 
                 2 
                 0.41 
               
               
                 2.540 
                 90 
                 60 
                 2 
                 0.41 
               
               
                 2.7295 
                 67.5 
                 100 
                 1 
                 0.41 
               
               
                 2.59 
                 22.5 
                 100 
                 1 
                 0.41 
               
               
                 2.48 
                 45 
                 100 
                 1 
                 0.41 
               
               
                 2.730 
                 270 
                 100 
                 1 
                 0.41 
               
               
                 2.59 
                 67.5 
                 100 
                 2 
                 0.41 
               
               
                 2.480 
                 0 
                 100 
                 2 
                 0.41 
               
               
                 2.730 
                 45 
                 100 
                 2 
                 0.41 
               
               
                 3.724 
                 45 
                 200 
                 ½ 
                 0.41 
               
               
                 4.103 4.098 
                   
                 200 
                   
                   
               
               
                 4.656 
                 45 
                 400 
                 1/2 
                 0.41 
               
               
                 2.73 
                   
                   
                   
                 0.41 
               
               
                   
               
            
           
         
       
     
       FIGS. 2A and 2B  show different views of another example lockout tagout plug sleeve  200  in accordance with one or more example embodiments. As described above with respect to  FIG. 1 , the lockout tagout plug sleeve  200  shown in  FIGS. 2A and 2B  includes a cylindrical body  210  that includes at least one wall  211  that forms a cavity  230 . The wall  211  includes a first end  216 , a second end  218 , a polarizing slot  214 , a pair of locking receivers  206 , and a lockout tagout hole  202 . 
     In this example, the cavity  211 , the first end  216 , the second end  218 , the polarizing slot  214 , and the lockout tagout hole  202  are substantially similar to the corresponding elements described above with respect to  FIG. 1 . In this example, the lockout tagout plug sleeve  200  of  FIG. 2 , the lockout tagout hole  202  is located at approximately 9:00, where 12:00 is represented by the polarizing slot  214 . Further, the pair of locking receivers  206  are substantially similar to those described above with respect to  FIG. 1 , except that in  FIGS. 2A and 2B  the pair of locking receivers  206  are parallel slots disposed laterally on the outer surface of the wall  211  of the cylindrical body  210 , and the pair of locking receivers  206  do not completely traverse or pierce the wall  211  of cylindrical body  210 . 
       FIG. 3  shows an example connector  300  (also called an electrical connector) that includes a lockout tagout plug sleeve  301  in accordance with one or more example embodiments. The lockout tagout plug sleeve  301  of  FIG. 3  is substantially similar to the lockout tagout plug sleeve  200  of  FIGS. 2A and 2B  above. In addition to the lockout tagout plug sleeve  301 , the connector  300  includes a plug assembly  370 . The plug assembly  370  includes three connector pins (two standard connector pins  342  and a ground pin  340 ), a connecting collar  320 , and a body  324 . In the example connector  300  of  FIG. 3 , the lockout tagout hole  302  of the lockout tagout sleeve  301  is located at approximately 6:00, where 12:00 is represented by the polarizing slot  314 . As described above, the lockout tagout hole  302  is positioned closer to the ground pin  340  of the plug assembly  370  than the other standard connector pins  342 . Alternatively, the lockout tagout hole  302  may be positioned closer to one of the standard connector pins  342  than the ground pin  340 . 
     In one or more example embodiments, the connecting collar  320  is used to couple the lockout tagout plug sleeve  301  to the body  324  of the plug assembly  370 , where the body houses the conductors that connect to the standard connector pins  342  and/or the ground pin  340 . The connector  300  may include one or more other elements and/or have one or more other configurations. The lockout tagout plug sleeve  301  may be configured to mechanically couple to the plug assembly  370  and/or to the corresponding receptacle (not shown). 
     The pins (e.g., the connector pins  342 , the ground pin  340 ) of the plug assembly  370  can be of any number (e.g., 2, 3, 4, 5) and be of the same and/or different lengths and/or widths relative to each other. In certain example embodiments, the pins of the plug assembly do not include a ground pin  340 . Alternatively, when the pins of the plug assembly include a ground pin  340 , the ground pin  340  can have the same and/or different length and/or a same and/or different width as the remainder of the pins (e.g., the connector pins  342 ). 
       FIG. 4  shows a cross-sectional perspective side view of an example electrical connector system  400  that includes a lockout tagout plug sleeve in accordance with one or more example embodiments. Specifically, the system  400  of  FIG. 4  includes the connector  300  of  FIG. 3  coupled to a corresponding receptacle  450 . The various components (e.g., lockout tagout plug sleeve  301 , plug assembly  370 ) of the system  400  are substantially the same as the corresponding components described above. Differences, alternatives, and/or additions to what has previously been described are described below. Example embodiments are not limited to the configuration shown in  FIG. 4  and discussed herein. 
     The receptacle  450  includes a receptacle body  452  that houses a receptacle insulator  454 . In certain example embodiments, there is a gap between the receptacle body  452  and the receptacle insulator  454 . When the receptacle  450  is mechanically coupled to the connector  300 , the lockout tagout plug sleeve  301  slides into the gap between the receptacle body  452  and the receptacle insulator  454 . Further, as the receptacle  450  is mechanically coupled to the connector  300 , the conductor pins  458  and the ground pin  456  is inserted into the connector pins  342  and the ground pin  340 , respectively, of the plug assembly  370 . In certain example embodiments, the conductor pins  458  and the ground pin  456  are disposed within the receptacle insulator  454 . 
     In this example, the ground pin  340  and the connector pins  342  of the plug assembly  370  have cavities, into which the ground pin  456  and conductor pins  458  of the receptacle  450  are disposed when the receptacle  450  and the plug assembly  370  are coupled to each other. Alternatively, the ground pin  456  and/or the conductor pins  458  of the receptacle  450  can have cavities, into which the ground pin  340  and/or the connector pins  342  of the plug assembly  370  can be disposed when the receptacle  450  and the plug assembly  370  are coupled to each other. 
     As can be seen in  FIG. 4 , the lockout tagout plug sleeve  301  is mechanically coupled to the plug assembly  370 . Specifically, the lockout tagout plug sleeve  301  is positioned between the plug body  443  and the plug insulator  441  of the plug assembly  370 . The lockout tagout hole  302  can be seen positioned adjacent to the ground pin  340  of the plug assembly  370  and the ground pin  456  of the receptacle  450 . Specifically, the ground pin  340  and the ground pin  456  are positioned within the cavity  330  of the lockout tagout plug sleeve  301  closer to the lockout tagout hole  302  than any of the connector pins  342  or the conductor pins  458 . 
     Example embodiments of the lockout tagout plug sleeve allow for easier application of a lockout tagout tag to a plug assembly. Application of the lockout tagout tag to the plug assembly is important to the safety of electricians, mechanics, and other personnel that work with or near electrical components. When the lockout tagout tag is applied to the lockout tagout hole of the example lockout tagout plug sleeve, an electrical connection using the plug assembly cannot be achieved. Thus, the associated system remains de-energized and safe for workers to perform maintenance work on the associated system. 
     Accordingly, many modifications and other embodiments set forth herein will come to mind to one skilled in the art to which lockout tagout plug sleeves pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that lockout tagout plug sleeves 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 this application. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.