Patent Publication Number: US-2022216639-A1

Title: Electrical connector assembly with plug and cavity assembly and method of ultrasonically welding

Description:
CROSS REFERENCE TO RELATED PATENT APPLICATION 
     This application is a Continuation of U.S. patent application Ser. No. 15/983,774, filed May 18, 2018, the disclosure of which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     This application relates generally to the field of wire electrical connectors and more specifically to plugs for sealing cavities in electrical connectors with an ultrasonic weld. 
     Automobiles may contain a large number of wires for connecting various electrical components. These wires are generally grouped in wire harnesses, which utilize electrical connectors to enable operators to quickly and easily electrically connect the components (e.g., forming wired connections with a male and female connector assembly) during assembly of the automobile. Each component may have a different number of wires that must be inserted into corresponding cavities in a multi-prong connector or connectors. As a result, when a standardized electrical connector is used for various components, each having a different number of wires, some of the cavities may remain unfilled with wires and exposed to the elements. Exposure of the wired electrical connection through the unfilled cavities may lead to damage or malfunction of the electrical connector assembly. For example, moisture entering the electrical connector assembly through the unfilled cavities may short circuit the wired connections and cause the electrical components to malfunction. Similarly, debris entering the electrical connector assembly through an unfilled cavity may interfere with the wired connections. 
     In order to protect the wired connections in the electrical connector assembly, the electrical connector assembly may be sealed, such that an interior portion of the assembly is isolated from outside elements. A plug may be inserted into any unfilled cavity to cover and protect the cavity. However, in a conventional electrical connector assembly, the plug does not positively engage the cavity and is therefore susceptible to fall out of the cavity as a result of vibrations or movement of the assembly over the life of the automobile. Alternatively, plugs that do positively engage the electrical connector include excess structure, which greatly increases the material cost of the electrical connector assembly. 
     It would therefore be advantageous to provide a plug to seal a cavity in an electrical connector, such that the plug both positively engages the cavity and minimizes material use by ultrasonically welding the plug in the cavity. 
     SUMMARY OF THE INVENTION 
     One embodiment relates to an assembly, including a plug at least partially disposed in a cavity of a connector at a front end of the connector. The plug ultrasonically welded to the connector in a configuration. The plug includes an inset portion and a recess formed within the inset portion. The inset portion extends axially into a body of the plug. The recess has a first closed surface forming an outer surface and configured to engage with a tool for aligning the plug with the cavity. The plug encloses the cavity with a second closed surface, such that the cavity is free from receiving a terminal or an electrical wire in the configuration. 
     Another embodiment relates to a connector assembly, including a plug at least partially disposed in a cavity of a connector at a front end of the connector. The plug ultrasonically welded to the connector in a configuration. The plug includes a first end, a second end opposite the first end, and a cap. The first end is at least partially disposed in the cavity of the connector. The cap is formed at the second end and extends annularly outward from the body. The cavity includes a receiving portion formed from a receiving wall defining a receiving portion diameter. 
     Another embodiment relates to a method of assembling an electrical connector assembly, the method including providing a connector defining a front end, an opposing rear end, and a cavity defined in the connector and extending from the front end to the rear end. The method further includes inserting a plug at least partially into the cavity, and ultrasonically welding the plug to the connector. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a connector assembly. 
         FIG. 2  is an exploded cross-sectional view of a connector according to one embodiment, including a plug for sealing the connector. 
         FIG. 3  is an assembled cross-sectional view of the connector of  FIG. 2 . 
         FIG. 4  is an exploded cross-sectional view of a connector according to another embodiment, including a plug for sealing the connector. 
         FIG. 5  is an assembled cross-sectional view of the connector of  FIG. 4 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to the FIGURES generally, an electrical connector assembly is shown according to various embodiments. The connector assembly is configured to provide a male and female connection between two corresponding connectors, each receiving a plurality of wires for connection. As will be discussed in further detail below, an unfilled cavity (e.g., a cavity that does not receive a wire therein) may be filled with a plug to fully enclose an interior portion of the connector assembly to protect the wired connections in the interior portion. 
     Referring now to  FIG. 1 , an electrical connector assembly  8  is shown according to one embodiment. The connector assembly  8  includes a first connector  10  (i.e., a connector, an electrical connector, etc.), having a substantially rectangular body  12  defining a front (i.e., first) end  14  and an opposing rear (i.e., second) end  16 . The body  12  further defines an upper surface  15  and an opposing lower surface  17 . It should be noted that while  FIG. 1  shows the first connector  10  with a rectangular body  12 , according to other embodiments, the body  12  may define other shapes. A plurality of cavities  18  are formed in the front end  14  and extend longitudinally through the body  12  to the rear end  16 . Specifically, each cavity  18  defines a front opening  20  formed in the front end  14  of the body  12  and an opposing rear opening  22  (shown in  FIG. 2 ) formed in the rear end  16  of the body  12 . 
     Each cavity  18  is configured to receive a metal terminal (not shown) therein and an exposed end of a wire in the terminal for passing electricity from the wire to the terminal at the rear end  16 . For example, the metal terminal may include a portion that is crimped onto the exposed end of the wire or electrically coupled to the wire in other suitable ways (e.g., soldered, welded, wound, etc.). The terminal is then inserted through the front end  14  of the first connector  10  into a cavity  18  by passing at least a portion of the terminal through the front opening  20  of the cavity  18 . When the terminal is fully inserted into and secured within the cavity  18 , at least a portion of the terminal is disposed proximate the rear end  16  of the body  12  or extends outward from the body  12  through the corresponding rear opening  22  at the rear end  16  (e.g., away from the front end  14 ). The terminal may be retained within the cavity  18  with an interference fit or press fit by the terminal against walls forming the cavity  18 , although the terminal may be retained in place in the cavity  18  in other ways. 
     According to another embodiment, the terminal may be inserted into the cavity  18  and then the end of the wire may be subsequently received in and electrically coupled to the terminal, as described above. According to yet another embodiment, the exposed end of the wire may be received in the cavity  18  without a terminal disposed in the cavity  18  between the wire and the walls of the cavity  18 . In this configuration, the wire may be coupled directly to the cavity  18  or another portion of the connector assembly  8 . 
     Referring still to  FIG. 1 , the connector assembly  8  further includes a second connector  30 , which is configured to electrically engage the first connector  10 . The second connector  30  may be substantially similar to the first connector  10 , including a substantially rectangular body  32  defining a front (i.e., first) end  34  and an opposing rear (i.e., second) end  36 . The body  32  further defines an upper surface  35  and an opposing lower surface  37 . It should be noted that while  FIG. 1  shows the second connector  30  with a rectangular body  32 , according to other embodiments, the body  32  may define other shapes, such that the shape of the body  32  corresponds to the shape of the body  12  of the first connector  10 . Specifically, the connector assembly  8  may be configured with a female component and a male component configured to be received in the female component. For example, one of the first or second connectors  10 ,  30  may be configured as a male component, which is configured to be received in the other of the first or second electrical connectors  10 ,  30 , which may be configured as a female component. 
     As shown in  FIG. 1 , the second connector  30  includes a plurality of cavities  38  formed in the front end  34  and extending laterally through the body  32  to the rear end  36 . The cavities  38  may be substantially similar to or the same as the cavities  18  in the first connector  10 , as discussed above. Each cavity  38  may define a front opening (not shown) formed in the front end  14  of the body  12  and an opposing rear opening  42  formed in the rear end  36  of the body  32 . When the connector assembly  8  is in the assembled configuration, the rear end  16  of the first connector  10  may be disposed against and receive or be received in a portion of the rear end  36  of the second connector  30 . In the connector assembly  8 , terminals and/or wires extending through the cavities  18  in the first connector  10  may contact and therefore electrically engage corresponding terminals and/or wires in the second connector  30  for transmitting electricity between the wires in the first and second connectors  10 ,  30 . 
     Referring still to  FIG. 1 , the plurality of cavities  18  may be organized in a grid formed in the front end  14  of the body  12 . It should be noted that while  FIG. 1  shows a grid having two rows of eight cavities  18 , this grid represents one embodiment and that the first connector  10  may include more or fewer cavities  18  in the body  12 , including with more or fewer rows and/or columns of cavities  18 . Furthermore, according other embodiments, the cavities  18  may be formed without a rectangular grid pattern and may be formed in a grid having other shapes or with no grid at all. 
     The second connector  30  may define the cavities  38  in a grid substantially the same as the cavities  18  in the first connector  10 , such that the rear opening  22  of each cavity  18  in the first connector  10  is configured to align with a corresponding rear opening  42  of each cavity  38  in the second connector  30  when the connector assembly  8  is fully assembled. However, in a configuration in which the grids are not both laterally and vertically symmetrical, the grid of the cavities  38  on the front end  34  of the second connector  30  may be substantially the same as the grid of the cavities  18  on the front end  14  of the first connector  10  transposed about one or both of a lateral or vertical axis defined coplanar with the front end  14  of the first connector  10 . 
     According to one embodiment, the second connector  30  may include a different number of cavities  38  than the number of cavities  18  in the first connector  10 . For example, the second connector  30  may include fewer cavities  38  than in the first connector  10 . In this configuration, cavities  18  in the first connector  10  without corresponding cavities  38  in the second connector  30  may be filled with plugs, as discussed in further detail below. Similarly, the first connector  10  may include fewer cavities  18  than in the second connector  30 . In this configuration, cavities  38  in the second connector  30  without corresponding cavities  18  in the first connector  10  may be filled with plugs. In either configuration, the first and second connectors  10 ,  30  may be configured to receive the same number of electrical wires therein. 
     Referring to  FIGS. 2-5  generally, a first connector  10  in a connector assembly  8  is shown according to various embodiment. It should be noted, however, that while  FIGS. 2-5  show the connector as the first connector  10 , the second connector  30  may be configured in substantially the same way as the first connector  10  and the male or female configuration of the connector  10 ,  30  does not limit the use of a plug to seal a corresponding cavity  18  therein. Further, while  FIGS. 2-5  only show one plug it should be understood that at least one plug may be provided to correspond with each unfilled cavity  18 , as well as in corresponding unfilled cavities  18  in the second connector  30 . 
     Referring now to  FIG. 2 , an exploded cross-sectional view of a first connector  10  is shown according to one embodiment. The cavity  18  defines a receiving portion  50  (i.e., a first portion) formed proximate the front opening  20 , a connecting portion  52  (i.e, a second portion) formed proximate the rear opening  22 , and a transition portion  54  (i.e., a third portion) extending therebetween. The receiving portion  50  is configured to receive and secure a plug  56  therein for sealing the cavity  18  at the front opening  20 . The connecting portion  52  is configured to engage and secure at least one of a terminal or a wire in place for electrical connection with the second connector  30 . 
     The front opening  20  defines a front edge  58  and an opposing rear edge  60  and a surface  62  extending therebetween. The surface  62  decreases in diameter and/or cross-sectional area moving away from the front end  14  toward the rear end  16 . For example, the front edge  58  defines a front diameter D 1  (i.e., a first diameter) and the rear edge  60  defines a rear diameter D 2  (i.e., a second diameter), which is less than the front diameter D 1 . As shown in  FIG. 2 , the surface  62  defines a substantially linear cross-sectional profile, forming a chamfer between the front edge  58  and the rear edge  60 . However, according to other embodiments the surface  62  may define other cross-sectional profiles (e.g., fillet or other curved surface) or may be threaded. According to another embodiment, the front diameter D 1  may be substantially the same as the rear diameter D 2 , such that the front opening  20  defines a substantially constant cross-sectional area between the front edge  58  and the rear edge  60 . In the configuration shown in  FIGS. 1 and 2 , the front opening  20  has a substantially circular profile, although it should be recognized that the front opening  20  may define other shapes corresponding to a shape of the plug  56 . 
     The receiving portion  50  extends from the rear edge  60  of the front opening  20 , away from the front end  14  and toward the connecting portion  52  and the rear end  16 . The receiving portion  50  defines a front edge  64  and an opposing rear edge  66  and a receiving wall  68  (i.e., a wall, a surface, etc.) extending therebetween. The front edge  64  defines a front diameter D 3  (i.e., a third diameter) and the rear edge  66  defines a rear diameter D 4  (i.e., a fourth diameter). The receiving portion  50  defines a receiving diameter D 5  (i.e., a fifth diameter) between the front edge  64  and the rear edge  66 , which is substantially constant and is substantially the same as the front diameter D 3  and/or the rear diameter D 4 . As shown in  FIG. 2 , the receiving diameter D 5  is substantially the same as the rear diameter D 2  of the front openings  20 , such that cavity  18  defines a constant diameter and cross-sectional area between the rear edge  60  of the front opening  20  and the rear edge  66  of the receiving portion  50 . In the configuration shown in  FIGS. 1 and 2 , the receiving portion  50  is annular in shape and has a substantially circular profile, although it should be recognized that the receiving portion  50  may define other shapes corresponding to the plug  56 , such that the receiving portion  50  defines substantially the same profile as the plug  56  to ensure a tight fit therebetween. Similarly, the receiving portion  50  may define substantially the same or different shape as the front opening  20 . 
     According to another embodiment, the receiving diameter D 5  may be different than the rear diameter D 2  of the front opening  20 , such that the diameter suddenly increases or decreases moving from the rear edge  60  of the front opening  20  to the front edge  64  of the receiving portion  50 . According to yet another embodiment, the receiving diameter D 5  may vary between the front edge  64  and the rear edge  66  and/or the front diameter D 3  may be different than the rear diameter D 4 . For example, the receiving diameter D 5  may decrease moving away from the front edge  64  toward the rear edge  66 , such that the receiving portion  50  is configured to engage the plug  56  as the plug  56  is inserted therein, with a press-fit arrangement. Specifically, the plug  56  will be further inserted into the receiving portion  50  until it engages the receiving wall  68  and a portion of the plug  56  is compressed by the receiving wall  68 . 
     Referring still to  FIG. 2 , the first connector  10  defines an interior portion  70  within the body  12  and formed proximate the rear end  16 . The interior portion  70  is configured to provide a void between the first connector  10  and the second connector  30  for electrically connecting the connector assembly  8 . While  FIG. 2  shows the interior portion  70  formed in just the body  12  of the first connector  10 , it should be understood that when the connector assembly  8  is fully assembled, the interior portion  70  extends within both the body  12  of the first connector  10 , proximate the rear end  16 , and the body  32  of the second connector  30 , proximate the rear end  36 . The interior portion  70  may include at least a portion of the cavities  18 ,  38  (e.g., at the connecting portion  52  thereof). In this or other configurations, the interior portion  70  is defined within the bodies  12 ,  32 , between the front end  14  of the first connector  10  and the rear end  36  of the second connector  30 . 
     The first connector  10  may sealingly engage the second connector  30  to seal and protect the interior portion  70  of the connector assembly  8 , including the electrical connection of the terminals in each of the first and second connectors  10 ,  30 . For providing a waterproof connector assembly  8 , the terminals may be further sealed within the cavities  18 ,  38  proximate the front openings  20  to prevent moisture from entering the interior portion  70  of the connector assembly  8 . 
     An arm  72  extends from the body  12 , proximate the rear edge  66  of the receiving portion  50 , toward the rear end  16  of the first connector  10 . The connecting portion  52  is defined between the arm  72  and the body  12 . As shown in  FIG. 2 , the connecting portion  52  is defined between the arm  72  and the upper surface  15  of the body  12 . A horn  74  extends from the arm  72  (e.g., proximate a rear end  76  of the arm  72 . The horn  74  may be angled toward the rear end  16  of the first connector  10  and away from the front end  14 . In this configuration, when the terminal or other structure is inserted into the cavity  18 , at least a portion of the terminal may positively engage the horn  74 . A channel  78  is defined between the arm  72  (e.g., at a side opposing the horn  74 ) and the lower surface  17  of the body  12 . The arm  72  is configured to deflect (e.g., under plastic deformation) away from the upper surface  15  of the body  12 , and into the channel  78 . For example, when the terminal is inserted into the cavity  18 , the terminal engages the horn  74  and causes the arm  72  to deflect as described. When the terminal is fully inserted into the cavity  18 , the arm  72  returns to its original position and a complementary feature of the terminal positively engages the horn  74 , such that the horn  74  provides an interference fit, preventing the terminal from being withdrawn from the cavity  18 . According to other embodiments, the horn  74  may be configured to engage a corresponding feature in a conventional plug in order to positively retain the conventional plug in the cavity  18 . In this configuration, the first connector  10  is configured to interchangeably receive either a conventional plug or the plug  56  described in the present application, reducing the number of parts required depending on the plug being used in a particular assembly. 
     While  FIG. 2  shows the connecting portion  52  defined between the arm  72  and the upper surface  15  of the first connector, according to other embodiments, the cavity  18  may extend proximate the lower surface  17 , such that the connecting portion  52  is defined between the arm  72  and the lower surface  17 . Similarly, in this configuration, the channel  78  may be defined between the upper surface  15  and the arm  72 , such that the arm  72  is configured to deflect away from the lower surface  17  toward the upper surface  15  when the terminal or other structure engages the horn  74 . According to other embodiments, the arm  72  may deflect when the terminal engages other portions of the arm  72 . 
     The connecting portion  52  defines a cross-sectional area that is less than the cross-sectional area of the receiving portion  50 . The transition portion  54  of the cavity  18  defines a taper with decreasing cross-sectional area moving away from the receiving portion  50  toward the connecting portion  52 . The transition portion  54  and/or the connecting portion  52  may define a substantially circular profile, such that the diameter of the cavity  18  decreases in the transition portion  54 . According to other embodiments, the connecting portion  52  defines other profile shapes and the transition portion  54  provides a smooth transition between the circular profile shape of the receiving portion  50  and the non-circular profile of the connecting portion  52 . 
     Referring still to  FIG. 2 , the plug  56  is shown according to one embodiment. The plug  56  includes a substantially annular body  80  having a first end  82 , configured to be received in the cavity  18  through the front opening  20 , and an opposing second end  84 . The body  80  defines a plug diameter D 6  (i.e., a sixth diameter), which is substantially the same as or less than the receiving diameter D 5 , such that the body  80  may be disposed in the receiving portion  50  of the cavity  18 . While  FIG. 2  shows the plug  56  having an annular body  80 , it should be understood that according to other embodiments, the body  80  may have other shapes corresponding to and substantially the same as the shape of the receiving portion  50 . 
     A cap  86  is formed at the second end  84  and extends radially outward from the body  80 . The cap  86  defines a cap diameter D 7  (i.e., a seventh diameter), which is greater than the plug diameter D 6  and the front diameter D 1  of the front opening  20 . Referring now to  FIG. 3 , when the plug  56  is inserted into the receiving portion  50  of the cavity  18 , the cap  86  is disposed against and engages the front end  14  of the first connector  10 . Due to the difference in diameter between the front diameter D 1  and the cap diameter D 7 , the cap  86  completely conceals the corresponding cavity  18  from view when the plug  56  is installed in the cavity  18 . 
     Referring again to  FIG. 2 , an inset portion  88  (e.g., a bore) is defined in the cap  86  and extends axially into the body  80 . It should be understood that the term “axially,” as used herein, may refer to the direction extending between the first end  82  and the second end  84  of the body  80 , and similarly, by the receiving portion  50  of the cavity  18 . The inset portion  88  may define a profile configured to engage a tool, such that the tool may hold the plug  56  for alignment with and insertion into the cavity  18 . For example, the inset portion  88  may have a hexagonal shape, may be a slot, or may define other profile shapes, which are configured to receive tools having corresponding shapes. According to another embodiment, the cap  86  may be substantially flat and may not include an inset portion  88 . 
     The plug  56  includes a collar  90 , which extends radially outward from the body  80  between the first end  82  and the cap  86 . The collar  90  defines a collar diameter D 5  (i.e., an eighth diameter), which is approximately the same as the receiving diameter D 5 . For example, the collar diameter D 5  may be substantially the same as or greater than the receiving diameter D 5 , such that the collar  90  is configured to frictionally engage the receiving wall  68  when the plug  56  is inserted into the cavity  18 . As shown in  FIG. 2 , the collar  90  forms a point at the collar diameter D 5  and is tapered inward moving toward both the first end  82  and the second end  84  of the plug  56 . According to other embodiments, the collar  90  may only be tapered inwardly in one direction (e.g., toward the first end  82  or toward the second end  84 ). Similarly, the first end  82  of the plug  56  may define a bevel, which improves the ability to locate the first end  82  of the plug  56  in the front opening  20  of the cavity  18 . 
     While  FIG. 2  shows the plug  56 , including the collar  90  having an annular profile, according to other embodiments, the plug  56  and/or the collar  90  may have other profiles. Specifically, portions of the cavity  18  (e.g., the receiving portion  50 ) may define a profile that is not annular (e.g., square, rectangular, etc.). In this configuration, one or both of the plug  56  itself or the collar  90  more specifically defines an outer profile that is complementary to or the same as the profile of the cavity  18  or more specifically of the receiving wall  68  forming the receiving portion  50 , such that the plug  56  may be received in the cavity  18 . Similarly, the outer profile of the collar  90  may be complementary to the profile of the surface  62  forming the front opening  20 . 
     Referring now to  FIG. 3 , the first connector  10  is shown with the plug  56  inserted into the cavity  18 . As shown in  FIG. 3 , the collar diameter D 8  is substantially the same as the receiving diameter D 5 . In this configuration, as the plug  56  moves axially into the receiving portion  50  of the cavity  18 , friction between the collar  90  and the receiving wall  68  limits or prevents movement of the plug  56  within the cavity  18  without applying an outside force on the plug  56 . 
     According to another embodiment, when the collar diameter D 8  is greater than the receiving diameter D 5 , the collar  90  engages the surface  62  of the front opening  20 , which thereby causes the collar  90  to deflect or deform (e.g., bend and/or compress) under plastic deformation. As the plug  56  is fully inserted in to the cavity  18  and the collar  90  engages the receiving wall  68 , the normal force between the collar  90  and the receiving wall  68  increases friction therebetween, such that the plug  56  is press-fit in the receiving portion  50  of the cavity  18 , thereby limiting movement of the plug  56  without applying an outside force on the plug  56 . The taper of the collar  90  reduces the amount of material present at an outer periphery of the collar  90 , thereby reducing the rigidity of the collar  90  and enabling the collar  90  to plastically deform when it engages the front opening  20  and the receiving wall  68 . 
     Once the plug  56  is fully inserted into the cavity  18  and at least a portion of the plug  56  engages the first connector  10 , the plug  56  is ultrasonically welded to the first connector  10 . High-frequency sound waves (i.e., acoustic vibrations) are applied to at least one of the plug  56  or the first connector  10 , which are both formed from plastic. The vibration of the plug  56  and the first connector  10  relative to each other causes frictional heat therebetween, melting a portion of the plastic of one or both of the plug  56  or the first connector  10  where the plug  56  engages the first connector  10 . When the vibrations are stopped, the melted plastic cools and solidifies, forming a hardened plastic coupling the plug  56  to the first connector  10 . According to one embodiment, each of the plug  56  and the first connector  10  are formed from the same plastic material, such that both the plug  56  and the first connector  10  have the same melting point. In this configuration, both the plug  56  and the first connector  10  melt where the plug  56  engages the first connector  10 . According to another embodiment, the plug  56  may be formed from a different plastic material with a lower melting point than the first connector  10 , such that the plug  56  melts during the ultrasonic welding process before or instead of the first connector  10 . 
     As discussed above, in the configuration shown in  FIG. 3 , the collar  90  engages receiving wall  68 . In this configuration, during the ultrasonic welding process, the collar  90  melts and/or a portion of the receiving wall  68  melts and the collar  90  is coupled directly to the receiving wall  68 . The collar  90  may be ultrasonically welded to the receiving wall  68  at specific discrete (i.e., separate) points along the outer periphery of the collar  90 . In this configuration, the press-fit between the collar  90  and the receiving portion  50  may provide a watertight seal therebetween, preventing moisture from entering the interior portion  70 , and the ultrasonic weld prevents the plug  56  from moving axially in the receiving portion  50  or being removed from the cavity  18  by vibrations or other external forces. According to another embodiment, the ultrasonic weld may be formed around substantially the entire outer periphery of the collar  90 , such that the weld itself forms a watertight seal between the collar  90  and the receiving wall  68 . 
     According to another embodiment, the cap  86  is integrally formed with the rest of the plug  56  from the same plastic material. At least a portion of one of the cap  86  and/or the front end  14  of the first connector  10  melts during the ultrasonic welding process, such that the cap  86  is coupled directly to the front end  14  and the plug  56  is coupled to the first connector  10  at an outer surface of the first connector  10 . According to other embodiments, the plug  56  may be ultrasonically welded to the first connector  10  in more than one location. At each of these locations, the weld may be formed at discrete points to prevent movement of the plug  56  without the weld itself forming a seal. According to other embodiments, the weld may be formed annularly around substantially the entire plug  56 , such that the weld forms a watertight seal between the plug  56  and the first connector  10 . 
     While the plug  56  may be plastically welded to the first connector  10  with ultrasonic welding, it should be recognized that the plug  56  may be welded to the first connector  10  in other ways. For example, the plug  56  may be rotated within the cavity  18  to generate friction between the collar  90  and the receiving wall  68 , which in turn increases the temperature of one or both of the collar  90  and the receiving wall  68 , until plastic forming at least one of the collar  90  and the receiving wall  68  melts. The assembly  8  then cools, as in ultrasonic welding, and the plug  56  is coupled to the receiving wall  68  with a plastic weld. In this configuration, the larger the collar diameter D 8  relative to the receiving diameter D 5 , the greater the frictional force between the collar  90  and the receiving wall  68 , which increases the heat output from friction during rotation and accelerates melting the plastic. Similarly, friction between the rotating cap  86  and the front end  14  of the first connector  10  may form a plastic weld therebetween, as discussed above with respect to ultrasonic welding. A tool may engage the inset portion  88  of the plug  56  in order to quickly rotate the plug  56  within the cavity  18 . 
     Referring still to  FIG. 3 , the plug  56  defines a plug length L 1  (i.e., a first length) measured from the cap  86  to the first end  82  of the plug  56 . The cavity  18  defines a receiving length L 2  (i.e., a second length), measured from the front end  14  of the first connector  10  to the rear edge  66  of the receiving portion  50 . As shown in  FIG. 3 , the plug length L 1  is less than the receiving length L 2 . Specifically, the plug length L 1  may be less than half of the receiving length L 2 . Notably, the smaller the plug length L 1 , the less material is required to form the plug  56 , thereby reducing material costs for the connector assembly  8 . A conventional plug would require a member to extend from the first end of the plug all the way into the connecting portion  52  of the cavity  18  in order to positively engage a corresponding feature in the cavity (e.g., the horn  74 ). In contrast, the ultrasonic weld between the plug  56  and the first connector  10  provides positive engagement between the plug  56  and the first connector  10 , thereby minimizing material use and cost for the connector assembly  8 . 
     Referring now to  FIG. 4 , the plug  56  is shown according to another embodiment. The plug  56  is substantially the same as the plug  56  shown in  FIGS. 2 and 3 . However, as shown in  FIG. 4 , the collar  90  defines a substantially annular (i.e., cylindrical) shape having rectangular cross-sectional profile, defining a flat outer periphery. In this configuration, the thickness of the collar  90  at the outer periphery limits the deformation of the collar  90  when it engages the receiving wall  68 . Referring to  FIG. 5 , in order to avoid damage to the collar  90 , the collar diameter D 5  may be substantially the same as the receiving diameter D 5 . In this configuration, the surface area available at an outer periphery of the collar  90  for ultrasonically welding the collar  90  to the receiving wall  68  is greater than with a tapered collar  90 . By increasing the available surface area, the vibrations in the ultrasonic welding process do not need to be applied as precisely to a specific portion of the collar  90  (e.g., the pointed edge of the tapered collar  90 ) to ensure that the plug  56  is welded to the receiving wall  68 . Similarly, while  FIGS. 3 and 5  show the collar  90  engaging the receiving wall  68 , according to another embodiment, the plug  56  may be formed without a collar  90 . In this configuration, the plug diameter D 6  is substantially the same as the receiving diameter D 5  and the body  80  is disposed directly against and is ultrasonically welded to the receiving wall  68 . 
     As utilized herein, the terms “approximately,” “about,” “substantially,” and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of this disclosure as recited in the appended claims. 
     It should be noted that the term “exemplary” as used herein to describe various embodiments is intended to indicate that such embodiments are possible examples, representations, and/or illustrations of possible embodiments (and such term is not intended to connote that such embodiments are necessarily extraordinary or superlative examples). 
     The terms “coupled,” “connected,” and the like as used herein mean the joining of two members directly or indirectly to one another. Such joining may be stationary (e.g., permanent) or moveable (e.g., removable or releasable). Such joining may be achieved with the two members or the two members and any additional intermediate members being integrally formed as a single unitary body with one another or with the two members or the two members and any additional intermediate members being attached to one another. 
     References herein to the position of elements (e.g., “top,” “bottom,” “above,” “below,” etc.) are merely used to describe the orientation of various elements in the FIGURES. It should be noted that the orientation of various elements may differ according to other exemplary embodiments, and that such variations are intended to be encompassed by the present disclosure. 
     It is to be understood that although the present invention has been described with regard to preferred embodiments thereof, various other embodiments and variants may occur to those skilled in the art, which are within the scope and spirit of the invention, and such other embodiments and variants are intended to be covered by corresponding claims. Those skilled in the art will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, mounting arrangements, use of materials, orientations, manufacturing processes, etc.) without materially departing from the novel teachings and advantages of the subject matter described herein. For example, the order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may also be made in the design, operating conditions and arrangement of the various exemplary embodiments without departing from the scope of the present disclosure.