Patent Publication Number: US-11651923-B2

Title: Two-piece fuse endbell with pre-cast/pre-molded alignment slots and optional interface crush ribs

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a continuation of, and claims the benefit of priority to, U.S. patent application Ser. No. 17/314,277, filed May 7, 2021, entitled “TWO-PIECE ENDBELL WITH PRE-CAST/PRE-MOLDED ALIGNMENT SLOTS AND OPTIONAL INTERFACE CRUSH RIBS,” which application is incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE DISCLOSURE 
     Embodiments of the present disclosure relate to fuse assemblies, and, more particularly, to fuse assemblies having two-piece endbells. 
     BACKGROUND 
     Used in electrical systems to protect against excessive current, fuses are sacrificial devices which break when an overcurrent condition occurs. Fuses include a fuse element, such as a metal wire or strip, that links two metal contact terminals together, and which melts/breaks if too much current flows. The breakage causes an open circuit, thus protecting devices to which the fuse is connected. Fuses come in a variety of shapes and sizes and have many applications, from small circuit electronics to large-scale industrial applications. In addition to being a component protection device, fuses are also safety devices, such as when used in vehicles, as they protect against fires in response to vehicle accidents. 
     Some fuses may include endbells at either side of the fuse body, with a fuse element disposed in the fuse body. The endbells are designed to support and protect the fuse element from external forces and environmental stresses. The existing fuse technology utilizes two fully circular endbells, each of which is engaged such as by first press-fitting or brazing into its respective separate terminal before the fuse element is attached. This assembly method thus involves a secondary process, such as soldering or welding, to attach the fuse element between the two terminals, increasing the complexity of manufacture and risking quality deviation. Further, the sliding interface between conductive terminal and endbell during assembly is not designed to produce a sealed envelope between fuse contents and the environment. 
     The endbells are secured to the fuse body using insertion pins. Drilling holes in the endbells, which are typically made of a softer metal than the metal used for the fuse terminal, can be messy, resulting in contaminants being left inside the fuse body. Tight sealing of the endbells to the fuse body ensures that the fuse assembly operates as designed. Thus, the endbells may be sealed to the fuse body using adhesive materials, which can also be messy. 
     It is with respect to these and other considerations that the present improvements may be useful. 
     SUMMARY 
     This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended as an aid in determining the scope of the claimed subject matter. 
     An exemplary embodiment of a fuse assembly in accordance with the present disclosure may include a fuse body, a terminal assembly, and an endbell. The terminal assembly is within the fuse body and has first and second opposing surfaces with a fuse element extending between a first terminal and a second terminal. The endbell, to be connected to the fuse body, includes first and second endbell portions. Formed within the first endbell portion is a first receptacle and extending from the first endbell portion is a first protrusion. Formed within the second endbell portion is a second receptacle and extending from the second endbell portion is a second protrusion. When the two endbell portions are fastened to one another with the terminal assembly sandwiched between them, the first protrusion engages the second receptacle and the second protrusion engages the first receptacle. 
     An exemplary embodiment of an endbell in accordance with the present disclosure is adapted to secure a terminal assembly inside a fuse housing and may include a first endbell portion and a second endbell portion. The first endbell portion has a first crush rib. The first crush rib is adapted to engage with a first surface of a terminal assembly. The second endbell portion has a second crush rib. The second crush is adapted to engage with a second surface of the terminal assembly opposite a first surface. 
     Another exemplary embodiment of a fuse assembly in accordance with the present disclosure may include a fuse body, an endbell portion, and an insertion pin. The fuse body is molded with first and second holes. The endbell portion is molded with a slot formed radially into its circumferential edge, forming a radial cavity through the endbell. The insertion pin extends through the first hole and the slot. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a diagram illustrating a fuse assembly, in accordance with exemplary embodiments; 
         FIGS.  2 A- 2 C  are diagrams illustrating a terminal assembly for the fuse assembly of  FIG.  1   , in accordance with exemplary embodiments; 
         FIGS.  3 A and  3 B  are diagrams illustrating endbell portions for the fuse assembly of  FIG.  1   , in accordance with exemplary embodiments; 
         FIGS.  4 A and  4 B  are diagrams illustrating endbell portion coupling for the fuse assembly of  FIG.  1   , in accordance with exemplary embodiments; 
         FIG.  5    is a diagram illustrating a fuse assembly, in accordance with exemplary embodiments; 
         FIGS.  6 A- 6 C  are diagrams illustrating a terminal assembly for the fuse assembly of  FIG.  5   , in accordance with exemplary embodiments; 
         FIGS.  7 A and  7 B  are diagrams illustrating endbell portion and endbell portion coupling of the fuse assembly of  FIG.  5   , in accordance with exemplary embodiments; 
         FIGS.  8 A and  8 B  are diagrams illustrating endbell portions for the fuse assembly of  FIG.  5   , in accordance with exemplary embodiments; 
         FIGS.  9 A and  9 B  are diagrams illustrating endbell portions for the fuse assembly of  FIG.  5   , in accordance with exemplary embodiments. 
         FIG.  10    is a diagram illustrating fuse assembly drilling, in accordance with the prior art; 
         FIG.  11 A  is a diagram illustrating an endbell portion with cylindrical holes, in accordance with exemplary embodiments; 
         FIG.  11 B  is a diagram illustrating an endbell portion with slots, in accordance with exemplary embodiments; and 
         FIG.  12    is a diagram illustrating a fuse assembly, in accordance with exemplary embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Novel fuse assembly designs are disclosed herein. Two-piece endbell designs enable the terminals and fuse element of the fuse assembly to be formed as a single piece, eliminating the manufacturing variability caused by having to separately attach the fuse element between the two terminals. The two-piece endbells as well as the terminal assembly feature elements that enable engagement of the endbell portions to the terminal assembly without use of adhesives. The elements also provide positioning guidance for ease of assembly. The endbell portions feature slots rather than cylindrical holes for receipt of insertion pins used to secure the endbells to the fuse body, thus avoiding costly rework of molding tools. 
     For the sake of convenience and clarity, terms such as “top”, “bottom”, “upper”, “lower”, “vertical”, “horizontal”, “lateral”, “transverse”, “radial”, “inner”, “outer”, “left”, and “right” may be used herein to describe the relative placement and orientation of the features and components of the fuse assemblies, each with respect to the geometry and orientation of the assemblies as they appear in the perspective, exploded perspective, and cross-sectional views provided herein. Said terminology is not intended to be limiting and includes the words specifically mentioned, derivatives therein, and words of similar import. 
     Fuse Assembly  100   
       FIG.  1    is a representative perspective view of a novel fuse assembly  100 , according to exemplary embodiments. The fuse assembly  100  features a fuse body  106 , which is transparent for ease of viewing other elements of the fuse assembly. Disposed at either end of the fuse body  106  are two endbells, a first endbell  102   a  and a second endbell  102   b  (collectively, “endbells  102 ”). A fuse element  108  is disposed between a first terminal  104   a  and a second terminal  104   b  (collectively, “terminals  104 ”). The fuse element  108  may assume shapes and configurations other than is shown in  FIG.  1   . As will be shown herein, the components of the fuse assembly  100  include features that facilitate secure affixation of the components as well as positioning guidance of the components during assembly, thus ensuring ease of manufacture. 
       FIGS.  2 A- 2 C  are representative perspective views of a terminal assembly along with endbells and endbell portions, which are part of the fuse assembly  100  of  FIG.  1   , according to exemplary embodiments.  FIG.  2 A  features a terminal assembly  200 A consisting of a fuse element disposed between two fuse terminals;  FIG.  2 B  features the fuse assembly  200 B having two attached endbells; and  FIG.  2 C  features the fuse assembly  200 C with an attached bottom first endbell portion and top second endbell portion (collectively, “terminal assembly  200 ”). 
     The terminal assembly  200 A ( FIG.  2 A ) consists of a fuse element  208  disposed between a first terminal  204   a  and a second terminal  204   b  (collectively, “terminals  204 ”). Known as the sacrificial portion of the fuse assembly  100  because it breaks in response to a fault condition, the fuse element  208  is shown as a simple, rectangular element having no bends or curves. In various alternative embodiments, the fuse element  208  may assume a variety of other shapes and sizes, may have twists or turns, may be thinner than or the same thickness as the terminals  204 , and may consist of multiple pieces which are not shown in the figures. The present disclosure is not limited in this regard 
     The fuse terminal  204  optionally includes terminal apertures  206   a  and  206   b  (collectively, “terminal apertures  206 ”) for fixably attaching the fuse to an electrical circuit. Though they are shown as circular openings, the terminal apertures  206  may be any of a variety of shapes and sizes. As one example, the fuse terminal  204  may be attached to a busbar by inserting electrically conductive bolts through the terminal apertures  206 , thus forming an electrical connection between the fuse and the busbar. 
     In an exemplary embodiment, the terminals  204  and the fuse element are formed as a unitary metallic, conductive material, such as zinc, copper, silver, aluminum, or alloys or combinations thereof, though the terminal assembly  200  shown and described herein is not limited to such a configuration. In other embodiments, the terminal assembly  200  of the fuse assembly  100  is formed by connecting the terminals  204  to either side of the fuse element  208 , such as by soldering, welding, or other means. 
     In an exemplary embodiment, the terminal assembly  200  features protruding lips formed proximate to each terminal. A first lip  212   a  and a second lip  212   b  are located on opposing sides of the terminal assembly  200  close to the first terminal  204   a ; similarly, a third lip  212   c  and a fourth lip  212   d  are located on opposing sides of the terminal assembly  200 , close to the second terminal  204   b  (collectively, “lips  212 ”). As illustrated in  FIG.  2 C , the lips  212  are mating features which facilitate connection of the endbells to the terminal assembly  200 , in exemplary embodiments. The lips  212  are described in more detail in conjunction with the description of  FIGS.  4 A and  4 B , below. 
     Endbells  202   a  and  202   b  are shown in  FIG.  2 B  (collectively, “endbells  202 ”). In exemplary embodiments, each endbell  202  consists of two parts or halves. The first endbell  202   a  consists of a first endbell portion  210   a  (bottom) and a second endbell portion  210   b  (top); the second endbell  202   b  consists of a first endbell portion  210   c  (bottom) and a second endbell portion  210   d  (top) (collectively, “endbell portions  210 ”). The endbell portions  210  are designed to be engaged with, such as by press-fitting, into the terminal assembly  200  at the location of the lips  212 . In an exemplary embodiment, the endbell portions  210  are manufactured using a zinc alloy. 
     In legacy fuse designs, the endbells are a single-piece design having a rectangular slot in each endbell. The fuse element is slid through the slots of each endbell, followed by the attachment of the terminals to each end of the fuse element, such as by soldering, welding, and the like. In exemplary embodiments, the two-piece endbell design of the fuse assembly  100  enables the terminals and fuse element to be formed as a single piece, eliminating the manufacturing variability caused by having to separately attach the fuse element between the two terminals. 
       FIG.  2 C  shows the endbell portion  210   a  of the first endbell  202   a  and the endbell portion  210   d  of the second endbell  202   b . In an exemplary embodiment, the endbell portions  210   a ,  210   b ,  210   c , and  210   d  are substantially similar and interchangeable with one another. The endbell portions  210  are disposed next to the terminal  204  at the location of the lips  212 . Described in more detail in conjunction with the descriptions of  FIGS.  3 A- 3 B and  4 A- 4 B , below, the endbell portions  210  include features that enable first and second endbell portions (e.g.,  210   a  and  210   b  of endbell  202   a  or  210   c  and  210   d  of endbell  202   b ) to mate with one another. Further, the lips  212  facilitate both placement of the endbell portions  210  and coupling of the endbell portions to the terminal assembly  200  of the fuse assembly  100 . 
     In exemplary embodiments, the endbells  202  further include insertion pins ( FIGS.  2 B and  2 C ). The first endbell  202   a  includes insertion pins  214   a  and  214   b ; the second endbell  202   b  includes insertion pins  214   c  and  214   d  (collectively, “insertion pins  214 ”). In one embodiment, the insertion pins  214  are made of a metal or metal alloy, such as stainless steel. The number of insertion pins may vary. In one embodiment, each endbell portion  210  includes one insertion pin  214 . In an exemplary embodiment, the insertion pins  214  enable connection between the endbells  202  and the fuse body  106  (see also  FIG.  1   ). The insertion pins  214  are described in more detail in in conjunction with the description of  FIG.  12   , below. 
       FIGS.  3 A and  3 B  are representative drawings of the endbell portions  210 , according to exemplary embodiments. The perspective views of the endbell portions  210  are given from different angles, making visible some additional details. Because each endbell portion  210  is substantially similar to each other endbell, whether disposed on top, on bottom, on the left side, or on the right side, of the terminal assembly  200 , the various features of the endbell portions are also substantially similar, in some embodiments. 
     Each endbell portion  210  includes a first diagonal surface  316 , a second diagonal surface  318 , a center (horizontal) surface  320 , a semi-circular surface  322 , and two flat side surfaces  324   a  and  324   b  (collectively, “side surfaces  324 ”). With the exception of the semi-circular surface  322 , the other surfaces are substantially flat. The center surface  320  is formed on either side of the first and second diagonal surfaces  316 ,  318 . 
     Each surface of the endbell portion  210  includes a feature. The side surfaces  324  show an endbell aperture  332 , which is a transverse cylindrical void visible on either side of the endbell portion  210 . The endbell aperture  332  is used to fill the fuse assembly  100  with sand or other material once the two endbells are connected to the fuse body, after which the aperture is sealed with plugs  338  on both sides ( FIG.  3 B ). The semi-circular surface  322  shows an insertion pin  214  extending radially from its surface. 
     Further, in exemplary embodiments, the first diagonal surface  316  features a receptacle  330  and the second diagonal surface  318  features a protrusion  328 . The receptacle  330  of one endbell portion  210  is designed to mate with the protrusion  328  of a second endbell portion. In exemplary embodiments, when the mating occurs, the diagonal surface  316  of one endbell portion  210  will be flush against the diagonal surface  318  of the other endbell portion. 
     The receptacle  330  includes a flat surface, known herein as a lip seat  334 , that extends from the center portion  320 , and a block receiver  340  orthogonal to the lip seat. Likewise, the protrusion  328  has a flat surface, a lip seat  336 , that extends from the center portion, and a block  342  orthogonal to the lip seat. In exemplary embodiments, two lips of the terminal assembly  200  mate with the endbell portion  210  so that one lip is disposed on the lip seat  334  of the receptacle  330 , while the second lip is disposed on the lip seat  336  of the protrusion  328  (see  FIG.  2 C ). This enables the terminal assembly  200  to be seated between two engaged endbell portions  210  that form the endbell  202 , such that a seal is formed between the endbell portions and the terminal assembly. Further, the block  342  of one endbell portion  210  engages the block receiver  340  of the other endbell portion. Designers of ordinary skill in the art will recognize that the lip seat  334  and block receiver  340  of receptacle  330  and the lip seat  336  and block  342  of protrusion  328  may vary in shape and size, while still providing the desired mating properties to the endbell portions  210 . Further, where the receptacle  330  and protrusion  320  are modified, the lips  212  of the terminal assembly  200  may be varied as well to facilitate mating of the components. 
     In exemplary embodiments, the center surface  320  features a crush rib  326  extending between (intermediate) the first diagonal surface  316  and the second diagonal surface  318 . In one embodiment, the crush rib  326  is disposed, not in the center of the center surface  320 , but to one side, closer to the side surface  324   b  than to the side surface  324   a . The crush rib  326  is also placed so as to avoid the lip seats  334 ,  336 , though the placement of the crush rib  326  may vary from what is illustrated. In an exemplary embodiment, when two endbell portions  210  are engaged with each other, the crush rib  326  of the upper endbell portion (e.g., endbell portion  210   b ,  FIG.  2 B ) is disposed directly over the crush rib of the lower endbell portion (e.g., endbell portion  210   a ), with the terminal assembly  200  disposed between the two endbell portions. In exemplary embodiments, the crush ribs  326 , along with the lips  212 , facilitate placement of the terminal assembly  200  between the two endbell portions  210 . In one embodiment, the terminal assembly  200  includes depressions or other receiving structures for mating with the crush ribs  326 . 
       FIGS.  4 A and  4 B  are representative drawings of endbell portion coupling  400  for the fuse assembly  100  of  FIG.  1   , according to exemplary embodiments.  FIG.  4 A  is an exploded perspective view and  FIG.  4 B  is a cross-sectional view of the endbell portion coupling  400 . The first endbell portion  210   a  and the second endbell portion  210   b  are disposed on either side of the fuse terminal  204 . Once the two endbell portions  210  are engaged with each other, such as by press-fitting together, with the lips  212  of the terminal assembly  200  disposed therebetween, the endbell portions are radially secured to one another, and a seal is formed between the endbell portions and the terminal assembly. 
     In exemplary embodiments, when the two endbell portions  210  are engaged with and radially secured to one another, the crush ribs  326  mate with the terminal assembly  200  and deform. A first crush rib  326   a  for endbell portion  210   a  and a second crush rib  326   b  for endbell portion  210   b  is shown. The terminal assembly  200 , which may be made from copper or copper alloy, is pressed firmly against the zinc or zinc alloy material of the endbell portions  210 , such that some compression and possibly deformation of the two materials occurs. In an exemplary embodiment, the pressure of connecting the crush ribs  326  against the terminal assembly  200  produces a sealed envelope between the contents of the fuse assembly  100  and the external environment. 
     Although a single crush rib  326  (per endbell portion  210 ) is shown, there may be multiple crush ribs  326  on each endbell portion. Further, these features may be presented in different locations on the respective endbell portions  210  without limitation. 
     In an exemplary embodiment, the endbell portions  210  are pressed around the terminal assembly  200  during manufacture, resulting in a concentric circular endbell on each end of the fuse ( FIGS.  1  and  2 B ). The features of each endbell portion  210  (the protrusions  328 , the receptacles  330 , and the crush ribs  326 ) can be used to both locate to mating features (the lips  212 ) on the terminal assembly  200  as well as align the two endbell portions. 
     In exemplary embodiments, once mated, the two endbell portions  210  become fixably attached without using an adhesive or sealant. This eliminates the need for endbell/terminal surface regularity. The crush ribs  326  in the endbell portions  210  bite into the terminal assembly  200 , deforming material in both the endbell portions and the terminal assembly. Thus, if the surface of either the endbell portion  210  or the terminal assembly  200  is not perfectly flat, the deformed-fit interface can still make a firm seal between the two materials. In an exemplary embodiment, the intentional interference of the crush ribs  326  with terminal assembly  200  provides mechanical support and a fixed connection between endbell portions  210  and the terminal assembly  200 . Further, in an exemplary embodiment, the pressure of connecting the crush ribs  326  with the terminal assembly  200  produces a sealed envelope between the fuse contents and the external environment. The mating elements of the novel fuse assembly  100  thus provide both secure affixation of the endbells to the fuse body and provide positioning guidance during assembly for ease of manufacturing the fuse assembly. 
     Fuse Assembly  500   
       FIG.  5    is a representative perspective view of a novel fuse assembly  500 , according to exemplary embodiments. The fuse assembly  500  features a fuse body  506 , which is transparent for ease of viewing other elements of the fuse assembly. Disposed at either end of the fuse body  506  are two endbells, a first endbell  502   a  and a second endbell  502   b  (collectively, “endbells  502 ”). A fuse element  508  is disposed between a first terminal  504   a  and a second terminal  504   b  (collectively, “terminals  504 ”). The fuse element  508  may assume shapes and configurations other than is shown in  FIG.  5   . As will be shown herein, both the endbells  502  and terminal assembly of the fuse assembly  500  include mating elements that provide secure affixation between the endbells and the fuse body, as well as providing positioning guidance for component assembly, thus facilitating ease of manufacture. 
       FIGS.  6 A- 6 C  are representative perspective views of a terminal assembly along with endbells and endbell portions, which are part of the fuse assembly  500  of  FIG.  5   , according to exemplary embodiments.  FIG.  6 A  features a terminal assembly  600 A consisting of a fuse element disposed between two fuse terminals;  FIG.  6 B  features the terminal assembly  600 B having two attached endbells; and  FIG.  6 C  features the terminal assembly  600 C with an attached bottom first endbell portion and top second endbell portion (collectively, “terminal assembly  600 ”). 
     The terminal assembly  600 A ( FIG.  6 A ) consists of a fuse element  608  disposed between a first terminal  604   a  and a second terminal  604   b  (collectively, “terminals  604 ”). The fuse element  608  is shown as a simple, rectangular element having no bends or curves but may assume a variety of shapes and sizes, as the particular shape or size of the fuse element  608  is not meant to be limiting. In an exemplary embodiment, the terminals  604  and the fuse element are formed as a unitary metallic, conductive material, such as zinc, copper, silver, aluminum, or alloys or combinations thereof. The present disclosure is not limited in this regard. 
     In an exemplary embodiment, the terminal assembly  600  features recesses disposed proximate to each terminal. A recess  612   a  and a recess  612   b  are located on opposing sides of the terminal assembly  600  close to the first terminal  604   a ; similarly, a recess  612   c  and a recess  612   d  are located on opposing sides of the terminal assembly  600 , close to the second terminal  604   b  (collectively, “recesses  612 ”). As illustrated in  FIG.  6 C , the endbell portion  610   a  includes a projection  616  that mates with the recess  612   b . The recesses  612  and projections  616  facilitate connection of the endbells to the terminal assembly  600 , in exemplary embodiments. The projections  616  are described in more detail in conjunction with the description of  FIG.  7 A , below. 
     Endbells  602   a  and  602   b  are shown in  FIG.  6 B  (collectively, “endbells  602 ”). In exemplary embodiments, each endbell  602  consists of two parts or halves. The first endbell  602   a  consists of a first endbell portion  610   a  and a second endbell portion  610   b ; the second endbell  602   b  consists of a first endbell portion  610   c  and a second endbell portion  610   d  (collectively, “endbell portions  610 ”). The endbell portions  610  are designed to be engaged with respective surfaces of the terminal assembly  600  at the location of the lips  612  and the projections  616 . In an exemplary embodiment, the endbell portions  610  are formed of a zinc alloy. 
       FIG.  6 C  shows the first endbell portion  610   a  of the first endbell  602   a  and the second endbell portion  610   d  of the second endbell  602   b . In an exemplary embodiment, the endbell portions  610   a ,  610   b ,  610   c , and  610   d  are substantially similar and interchangeable with one another. The endbell portions  610  are disposed next to the terminal  604  at the location of the recesses  612 . Described in more detail in conjunction with the descriptions of  FIGS.  7 A- 7 B  and  FIGS.  8 A- 8 B , below, the endbell portions  610  include features that enable first and second endbell portions (e.g.,  610   a  and  610   b  of endbell  602   a  or  610   c  and  610   d  of endbell  602   b ) to mate with one another. Further, the recesses  612  facilitate both placement of the endbell portions  610  and coupling of the endbell portions to the terminal assembly  600  of the fuse assembly  500 . 
     Although  FIGS.  6 B and  6 C  show endbell portions  610 , in an alternative embodiment, the terminal assembly  600  and the fuse assembly  500  may alternatively be fitted with endbell portions  810 , as illustrated and described in  FIGS.  8 A and  8 B , below. 
     In exemplary embodiments, the endbells  602  further include insertion pins ( FIGS.  6 B and  6 C ). The first endbell  602   a  includes insertion pins  614   a ,  614   b , and  614   c ; the second endbell  602   b  includes insertion pins  614   d ,  614   e , and  614   f  (collectively, “insertion pins  614 ”). In exemplary embodiments, each endbell  602  further includes a fourth insertion pin (not shown). In one embodiment, the insertion pins  614  are made of a metal or metal alloy, such as zinc alloy. The number of insertion pins may vary. In one embodiment, each endbell portion  610  includes two insertion pins  614 . In an exemplary embodiment, the insertion pins  614  enable connection between the endbells  602  and the fuse body  106  (see also  FIG.  5   ). The insertion pins  614  are described in more detail in in conjunction with the description of  FIG.  12   , below. 
       FIGS.  7 A and  7 B  are representative drawings of endbell portion  610  and endbell portion coupling  700 , respectively, according to exemplary embodiments.  FIG.  7 A  shows an endbell portion  610 ;  FIG.  7 B  shows a cross-sectional view of the endbell portion coupling  400  for the fuse assembly  500  of  FIG.  5   . Because each endbell portion  610  is substantially similar to each other endbell portion, whether disposed on top, on bottom, on the left side, or on the right side, of the terminal assembly  600 , the various features of the endbell portions are also substantially similar. 
     Each endbell portion  610  includes a feature surface  720 , including a raised portion  718 , a semi-circular surface  722  at a circumferential edge of the endbell portion, and two flat side surfaces  724   a  and  724   b  (collectively, “side surfaces  724 ”). Side surface  724   a  shows an endbell aperture  732 , which is a transverse cylindrical void visible on either side of the endbell portion  610 . The endbell aperture  732  is used to fill the fuse assembly  500  with sand or other material once the two endbells are connected to the fuse body, after which the aperture is sealed with plugs on both sides ( FIGS.  5  and  6 B ). 
     In exemplary embodiments, the feature surface  720  includes a protrusion  728  while the raised portion  718  of the feature surface  720  includes a receptacle  730 . The receptacle  730  of one endbell portion  610  is designed to receive the protrusion  728  of a second endbell portion, thereby mating the two endbell portions. In exemplary embodiments, when the mating occurs, the raised portion  718  is raised up, relative to the feature surface  720 , thus allowing room for the terminal assembly  600  to be disposed between the two endbell portions  610 . 
     First introduced in  FIG.  6 C , the projection  616  of the raised portion  718  extends into the feature surface  720 . In exemplary embodiments, the recesses  612  of the terminal assembly  600  mate with respective projections  616  of the endbell portion  610  so that the endbell portions can successfully mate with the terminal assembly  600 . The recesses  612  and projections  616  thus provide a guide for positioning of the endbell portions  610  upon the upper and lower surfaces of the terminal assembly  600 . Designers of ordinary skill in the art will recognize that the recesses  612  and projections  616  may vary in shape and size, while still providing the desired mating properties to the endbell portions  610 . 
     In exemplary embodiments, the feature surface  720  further features two crush ribs  726   a  and  726   b  disposed at the edges of the feature surface (collectively, “crush ribs  726 ”). In an exemplary embodiment, when two endbell portions  610  are engaged with one another, the crush rib  726   a  of the first endbell portion (e.g., endbell portion  610   b ,  FIG.  6 B ) is disposed directly over the crush rib of the second endbell portion (e.g., endbell portion  610   a ), with the terminal assembly  600  disposed between the two endbell portions, thus forming a seal between the endbell portions and the terminal assembly. Similarly, the crush rib  726   b  of the one endbell portion is disposed directly over a second crush rib of another endbell portion. In exemplary embodiments, the projection  616  facilitates placement of the each endbell portion  610  upon the terminal assembly  600 . 
     In exemplary embodiments, the protrusion  728  of the endbell portion  610  further includes one or more ribs. Ribs  736   a  and  736   b  are visible in  FIG.  7 A  (collectively, “ribs  736 ”), though there may be more or fewer ribs than are shown. The ribs  736  on the protrusion  728  are another engagement feature which deform in the receptacle  730  during assembly to retain the relative positions of the two endbell portions  610 . Thus, when the endbells  610  are engaged with one another, the ribs  736 , like the crush ribs  726 , facilitate melding of the respective components together, resulting in an air-tight coupling and formation of a seal between the endbells  602  without use of adhesive. The recesses  612  and projections  616  similarly help seal the endbell portions  610  against the terminal assembly  600 . 
     In exemplary embodiments, as illustrated in the cross-sectional view of  FIG.  7 B , when the two endbell portions  610  are engaged with and radially secured to one another, the crush ribs  726  mate with the terminal assembly  600  and deform. First and second crush ribs  726   a  and  726   b  for endbell portion  610   b  and third and fourth crush ribs  726   c  and  726   d  for endbell portion  610   a  are shown. The terminal assembly  600 , which may be made from copper or copper alloy, is pressed firmly against the zinc or zinc alloy material of the endbell portions  610 , such that some compression and/or deformation of the two materials occurs. The optional ribs  736  also facilitate the fixed coupling of the two endbell portions  610 . In an exemplary embodiment, the pressure of connecting the crush ribs  726  with the terminal assembly  600  produces a sealed envelope between the contents of the fuse assembly  500  and the external environment. 
     In an exemplary embodiment, the endbell portions  610  are pressed around the terminal assembly  600  during manufacture, resulting in a concentric circular endbell on each end of the fuse ( FIGS.  5  and  6 B ). The features of each endbell portion  610  (the protrusions  728  and the receptacles  730 ) can be used to align the two endbell portions while the projection  616  of each endbell portion is used to “locate” respective recesses  612  on the terminal assembly  600 . 
     In exemplary embodiments, once mated, the two endbell portions  610  become fixably attached without using an adhesive or sealant. This eliminates the need for endbell/terminal surface regularity. The crush ribs  726  in the endbell portions  610  bite into the terminal assembly  600 , deforming material in both the endbell portions and the terminal assembly. Thus, if the surface of either the endbell portion  610  or the terminal assembly  600  is not perfectly flat, the engagement interface can still make a firm seal between the two materials. In an exemplary embodiment, the intentional interference of the crush ribs  726  with the surfaces of the terminal assembly  600  provides mechanical support and a fixed connection between endbell portions  610  and the terminal assembly. Further, in an exemplary embodiment, the pressure of connecting the crush ribs  726  the terminal assembly surfaces produces a sealed envelope between the fuse contents and the external environment. 
       FIGS.  8 A and  8 B  are representative drawings of endbell portion  810 , according to exemplary embodiments.  FIG.  8 A  is a perspective view and  FIG.  8 B  is a cross-sectional view of the endbell portion  810 . The endbell portion  810  may be part of the fuse assembly  500  of  FIG.  5   . The endbell portion  810  features a feature surface  820  with a raised portion  818 , where the feature surface  820  includes a protrusion  828  and the raised portion includes a receptacle  830 . The protrusion  828  and receptacle  830  facilitate connection of the endbells  610  to the terminal assembly  600 , in exemplary embodiments. The endbell portion  810  also features a projection  816 . The projection  816  is designed to mate with the recess  612  of the terminal assembly  600  ( FIG.  6 C ). The recesses  612  and projections  816  facilitate positioning guidance when connecting the endbell portions to the terminal assembly  600 , in exemplary embodiments. 
     As with the endbell  610  ( FIGS.  7 A and  7 B ), the endbell  810  also features two crush ribs  826   a  and  826   b  disposed at the edges of the feature surface  820  (collectively, “crush ribs  826 ”). In an exemplary embodiment, when two endbell portions  810  are engaged with one another, such as by press-fitting, the crush rib  826   a  of the upper endbell portion is disposed directly over the crush rib of the lower endbell portion, with the terminal assembly  600  disposed between the two endbell portions. Similarly, the crush rib  826   b  of the upper endbell portion is disposed directly over a second crush rib of the lower endbell portion. In exemplary embodiments, the two crush ribs  826 , along with the projection  816 , facilitate placement of the each endbell portion  810  upon the terminal assembly  600 . 
     Further, in exemplary embodiments, the endbell  810  features troughs which are adjacent to the crush ribs  826 . Trough  844   a  is adjacent to crush rib  826   a  while trough  844   b  is adjacent to crush rib  826   b  (collectively, “troughs  844 ”). In the cross-sectional view of  FIG.  8 B , the crush ribs  826  are shown as projections while the troughs  844  are shown as depressions. When the endbell portions  810  are engaged together, sometimes the crush ribs  826  are substantially compressed and/or deformed, such that the excess material of the compression/deformation is able to fit into the troughs  844 . Where the compression/deformation causes a smaller interference, there may be less excess material, rendering the troughs  844  unused. The endbell portion  810  thus offers additional flexibility for the assembly of the fuse assembly  500 . The mating elements of the novel fuse assembly  500 , different from those of the fuse assembly  100 , also provide both secure affixation of the endbells to the fuse body and provide positioning guidance during assembly for ease of manufacturing the fuse assembly. 
       FIGS.  9 A and  9 B  are representative drawings of endbell portion coupling  900 , according to exemplary embodiments.  FIG.  9 A  is a perspective view and  FIG.  9 B  is a cross-sectional view of the endbell portion coupling  900 . A terminal assembly  902  is shown disposed between a first endbell portion  910   a  and a second endbell portion  910   b  (collectively, “endbell portions  910 ”). The elements shown in  FIGS.  9 A and  9 B  may be part of the fuse assembly  500  ( FIG.  5   ). The second endbell portion  910   b , though showing fewer features, is substantially similar to the first endbell portion  910   a , in exemplary embodiments. The terminal assembly  902  shares some similarities to the aforementioned terminal assemblies  200  and  600  and the endbell portions  910  share some similarities to the aforementioned endbell portions  610  and  810 . 
     The endbell portions  910  feature both a protrusion  928  and a receptacle  930 . The protrusion  928  of one endbell portion  910  is designed to fit into the receptacle of a second endbell portion. The terminal assembly  902  features a recess  912   a  and a recess  912   b  (collectively, “recesses  912 ”), which are disposed on opposing edges of the terminal assembly. The bottom endbell portion  910   a  shows a projection  916 , and the endbell portion  910   b , which is substantially similar to endbell portion  910   a , also includes a projection. These projections  916  are designed to mate with respective recesses  912  of the terminal assembly  902 , in exemplary embodiments. When the two endbell portions  910  are engaged with one another, the projection  916  of the endbell portion  910   a  will fit into the recess  912   a , with the recess (not shown) of the endbell portion  912   b  fitting into the recess  912   b.    
     In exemplary embodiments, the endbell portion  910   a  further includes a pair of crush ribs  926   a  and  926   b  (collectively, “crush ribs  926 ”). On either side of each crush rib  926  are troughs. Thus, crush rib  926   a  is disposed on either side of trough  944   a  and  944   b , while crush rib  926   b  is disposed on either side of trough  944   c  and  944   d  (collectively, “troughs  944 ”). When the endbell portions  910  are engaged with one another, sometimes the crush ribs  926  are substantially compressed and/or deformed, such that the excess material of the compression/deformation is able to fit into the troughs  944 , whether to one side of the crush rib, to a second side of the crush rib, or to both sides of the crush rib. Where the compression/deformation causes a smaller interference, there may be less excess material, rendering one or more of the troughs  944  unused. 
     In exemplary embodiments, the terminal assembly  902  includes mating grooves for coupling with the crush ribs  926  of the endbell portions  910 . On a first surface of the terminal assembly  902 , a first mating groove  942   a  is in one side of the recesses  912  and a second mating groove  942   b  is in another side of the recesses; on a second surface of the terminal assembly, a third mating groove  942   c  is in one side of the recesses and a second mating groove  942   d  is in another side of the recesses (collectively, “mating grooves  942 ”). In exemplary embodiments, the mating grooves  942  are spaced a distance, d, apart and the crush ribs  926  are also spaced a distance, d, apart. The mating grooves  942  of the terminal assembly  902  are thus receiving structures for mating with the crush ribs  926  of the endbell portions  910 . 
     The terminal assembly  902 , which may be made from copper or copper alloy, is pressed firmly against the zinc or zinc alloy material of the endbell portions  910 , such that some compression and possibly deformation of the two materials occurs. In an exemplary embodiment, the pressure of connecting the crush ribs  926  against respective mating grooves  942  of the terminal assembly  910  produces a sealed envelope between the contents of the fuse assembly and the external environment. The crush ribs  926  and the mating grooves  942  facilitate melding of the respective components together, resulting in an air-tight coupling into the endbells without use of adhesive. The recesses  912  and projections  916  similarly help seal the endbell portions  910  against the terminal assembly  902 . 
     In exemplary embodiments, the projection  916  of the endbell portions  910  and the recesses  912  of the terminal assembly  902  provide positioning guidance during manufacture of the fuse assembly  500 . With the addition of mating grooves  942  in the terminal assembly  902 , this positioning guidance is enhanced, in exemplary embodiments, as the crush ribs  926  of the endbell portions  910  are able to “find” the mating grooves of the terminal assembly  902  for ease of manufacturing the fuse assembly. 
     Insertion Pin Slots 
     The fuse assemblies described above feature insertion pins, which are used to secure the endbells to the fuse body. In legacy fuse assemblies, cylindrical holes are drilled into both the endbells and the fuse body. The holes retain the endbells axially within the cylindrical tube of the fuse body. 
       FIG.  10    is an illustration of a legacy drilling process of a fuse assembly according to the prior art. The drilling operation can be quite messy and may cause contamination inside the fuse assembly, which can negatively impact operation of the fuse element. For example, conductive materials from the drilling operation, if left inside the fuse assembly, may cause current to flow between the two terminals, even though the fuse element has been broken due to a fault condition. The material from the drilling operation may thus cause the fuse to not function as designed. 
     To retain the endbells at opposing ends of the fuse, holes are to be drilled radially to a specified depth through the fuse body and into the endbells. Metal pins are then inserted into the holes, rigidly retaining the endbells in place. Drilling into most fuse body materials is fast, efficient, and does not easily dull the drill bit. Drilling a blind hole into the endbell portion is risky because there is uncertainty about whether the drill hole is in the correct location. Further, drilling a blind hole into zinc is difficult, slow, and dulls the drill bit quickly and damages the drill bit with high regularity, which poses a problem for mass production. Because they are made from zinc or zinc alloy, drilling holes in the endbell portions  210 ,  610 , or  910  is problematic, in some embodiments. 
     As an alternative to drilling, the endbell portions may be made using molding operations, such as injection molding. The core and cavity are the shaped sections in either half of the mold tool that give the endbell portion its final shape. The cylindrical holes used for the insertion pins can be molded in this way. 
     There may be drawbacks with using molding operations for the cylindrical holes, however.  FIG.  11 A  is a representative drawing of an endbell portion with cylindrical holes, in accordance with exemplary embodiments. Endbell portion  1100  may be similar to endbell portions  210  of fuse assembly  100  or endbell portions  610  or  910  of fuse assembly  500 . Two cylindrical holes  1104   a  and  1104   b  are shown, radially disposed in the circumferential edge of the endbell portion  1100 , forming radial cavities (collectively, “holes  1104 ”). 
     The upward vertical arrow indicates tool cavity pull while the downward vertical arrow indicates tool core pull of the molding operation. The diagonal arrows indicate tooling slide for the holes  1104 . Unfortunately, during the tooling of the holes  1104 , an interrupted surface profile, given by parting lines  1106   a  and  1106   b , adds risk for consistent assembly to the fuse body. 
     Adding diecast/molded holes (as opposed to slots) require additional slides to be added to the tool, which in turn create an inconsistent surface due to the additional parting-lines. As this is the mating surface between the endbell exterior and the body interior, a consistent surface for the endbell is preferred.  FIG.  11 A  thus shows an inefficient tooling layout. The diagonal lines indicate tooling “slides” that are not aligned with the tool pulling direction, which adds both cost and additional parting lines to the final part. 
     As an alternative, in exemplary embodiments, the endbells are formed in a molding operation with slots, rather than cylindrical holes. The slots are designed specifically to eliminate the need to add side actions in the molding tool and maintain a smooth uninterrupted endbell surface. 
       FIG.  11 B  is a representative drawing of an endbell portion having slots  1150 , in accordance with exemplary embodiments. Using a molding operation rather than drilling, two slots  1112   a  and  1112   b  are formed radially into the circumferential edge of the endbell portion  1150  (e.g., the semi-circular surface), forming radial cavities (collectively, “slots  1112 ”). Again, the upward vertical arrow indicates tool cavity pull while the downward vertical arrow indicates tool core pull. Unlike the holes  1012 , the slots  1112  allow for direct pull direction from the tool cavity. In some embodiments, added slots are designed specifically to eliminate the need to add side actions in the molding tool and maintain a smooth uninterrupted endbell surface. In exemplary embodiments, the non-conductive material making up the fuse, such as fuse body  106  ( FIG.  1   ) and fuse body  506  ( FIG.  5   ), are also made using a molding process with the holes being part of the core and cavity of the fuse body, thus eliminating the need to drill holes in the fuse body. 
     Parting lines  1114   a  and  1114   b  are shown in slot  1112   a  and parting lines  1114   c  and  1114   d  are shown in slot  1112   b  (collectively, “parting lines  1114 ”). In contrast to the parting lines  1106  in  FIG.  11 A , the parting lines  1114  of endbell  1110  do not affect the surface of the endbell, but only the slots themselves, which will receive insertion pins during assembly. The alternative molding operation of  FIG.  11 B  thus ensures a consistent minimally interrupted surface profile for improved assembly to the fuse body, in some embodiments.  FIG.  11 B  thus shows the improved tooling layout, relative to that of  FIG.  11 A , in exemplary embodiments. By using slots rather than cylindrical holes, the slots are produced by tooling with the same pull direction as the rest of the tool. 
     Fuse Assembly  1200   
       FIG.  12    is a representative exploded perspective drawing of a fuse assembly  1200  featuring endbells with pre-molded alignment slots, according to exemplary embodiments. A fuse body  1206  and a cross-section of a single endbell  1202  are shown. The endbell  1202  may be a two-part endbell, such as the endbells  102  and  502  of the fuse assemblies  100  and  500 , respectively. Fuse terminals  1204   a  and  1204   b  are shown at either end of the fuse body  1206 . 
     The fuse body  1206  includes fuse body holes  1216   a ,  1216   b ,  1216   c , and  1216   d , shown in the cross-section of the endbell  1202 , as well as fuse body hole  1216   e , shown on the opposing side of the fuse body, for securing a second endbell (not shown) (collectively “fuse body holes  1216 ”). 
     In exemplary embodiments, diecast/molded slots of predetermined size and orientation are located on each endbell  1202 , removing the need to drill. Alignment slots  1212   a ,  1212   b ,  1212   c , and  1212   d  are pre-molded into the circumferential surface of the endbell  1202 , such as is shown in  FIG.  11 B  (collectively, “alignment slots  1212 ” or “slots  1212 ”). The cross-sectional view shows that the slots  1212  are somewhat trapezoid-shaped, with the top of the slots near the circumferential surface of the endbell  1202  being wider than at the bottom, in some embodiments. Visible in the alignment slot  1212   b , a slot bottom  1218  is circular, in some embodiments, though shown as a semi-circle in the cross-sectional view. 
     Also featured in the fuse assembly  1200  are insertion pins  1214   a ,  1214   b , and  1214   d  for securing the endbell  1202  as well as insertion pins  1214   e ,  1214   f , and  1214   g , for securing the second unshown endbell (collectively, “insertion pins  1214 ”). Not visible insertion pins  1214  are presumed to be insertable in the fuse body hole  1216   c  and slot  1212   c  for the endbell  1202  and for the not visible endbell. In one embodiment, the insertion pins  1214  are made of a metal or metal alloy material, such as stainless steel. In an exemplary embodiment, four insertion pins  1214  are used to secure each endbell, though the number of insertion pins may vary. 
     Together, the fuse body holes  1216  and the slots  1212  receive the insertion pins  1214  to secure the endbell  1202  and not visible endbell to the fuse body  1206 . The pre-cast/pre-molded alignment slots  1212  significantly simplify the fuse manufacturing process by removing the need to drill into the fuse endbells without adding tooling complexity. Using slots  1212  in the endbells  1202  (rather than cylindrical holes) allow the endbell tooling to remain basic with simple core/cavity blocks, avoiding costly side-action features in the tooling. The use of slots thus minimally impacts tooling cost and piece part cycle time, in some embodiments. Further, having pre-cast/pre-molded endbell slots allow for the fuse body to be independently drilled prior to assembly. 
     Further, in exemplary embodiments, the presence of the pre-cast/pre-molded alignment slots  1212  eliminates the risk of metal particulate entering the functional region of the fuse due to endbell drilling. The endbell slot design of  FIG.  12    both guides pin insertion alignment and permits the action of drilling holes into the fuse body to be performed at any time separately from the rest of the assembly, in exemplary embodiments. 
     As used herein, an element or step recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural elements or steps, unless such exclusion is explicitly recited. Furthermore, references to “one embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. 
     While the present disclosure makes reference to certain embodiments, numerous modifications, alterations, and changes to the described embodiments are possible without departing from the sphere and scope of the present disclosure, as defined in the appended claims. Accordingly, it is intended that the present disclosure not be limited to the described embodiments, but that it has the full scope defined by the language of the following claims, and equivalents thereof.