Patent Publication Number: US-9412495-B1

Title: Wire and cable having integrally formed jacket and partitioned wall members and process and apparatus for making the same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     REFERENCE TO A COMPACT DISK APPENDIX 
     Not applicable. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to electrical cables, and particularly non-metallic electrical cables with integrally formed jacket and partitioned wall members. 
     2. Description of Related Art 
     NM-B cable is a common form of indoor residential electrical wire. Traditional NM-B cable consists of two or more PVC insulated conductors and a bare grounding conductor. The bare grounding conductor is individually wrapped in a paper sheath. Additionally, all of the insulated conductors and the bare ground wire may be wrapped in a paper sheath that encompasses the entire wire construction. A PVC jacket is the outermost layer of the construction and encapsulates all of the wires and paper. This construction has been used for a number of years. 
     Traditional NM-B cable presents several shortcomings. First, traditional NM-B is inconvenient for installation due to the need to remove the paper surrounding the bare grounding conductor. Second, traditional NM-B uses a significant amount of paper, thereby increasing the cost of the wire and depleting natural resources. Third, the inclusion of paper in making traditional NM-B cable slows down the production rate. Fourth, during production the paper may tear, resulting in halting the production process and scrap wire. Thus, there is a need for an NM-B cable that can overcome these shortcomings by eliminating the need for a paper. 
     BRIEF SUMMARY OF THE INVENTION 
     The present disclosure is directed to a non-metallic cable having an integrally formed jacket and partitioned wall members and method and apparatus for making the same. In one embodiment, an electrical cable comprises a non-metallic jacket that encapsulates an insulated conductor and a bare grounding conductor, wherein the insulated conductor and the bare grounding material are separated by a wall that runs the length of the electrical cable and is integrally formed with the jacket. In another embodiment, a die assembly unit is used to form a non-metallic cable having an integrally formed jacket and partitioned wall members, wherein the die assembly unit comprises a die assembly nozzle comprising an extrusion tip having an at least one wall channel and a curved angled surface, operating in conjunction with a die assembly cap. 
     In another embodiment the manufacturing of the electrical cable is accomplished by a method comprising providing a material, extruding the material into a die assembly unit, feeding a bare grounding conductor through an extrusion tip having an at least one wall channel, feeding an insulated conductor and a bare grounding conductor through the extrusion tip, engaging the material with the extrusion tip, whereby the material conforms to the extrusion tip and the at least one wall channel, whereby the material encapsulates the bare grounding conductor and insulated conductor, thereby forming a finished electrical cable having an integrally formed jacket and at least one partitioned wall. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The foregoing summary, as well as the following detailed description, will be better understood when read in conjunction with the appended drawings. For the purpose of illustration, there is shown in the drawings certain embodiments of the present disclosure. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. 
       In the drawings: 
         FIG. 1  illustrates an end view of an embodiment of an electrical cable having an integrally formed jacket and partitioned walls; 
         FIG. 2  illustrates an embodiment of a die assembly nozzle for manufacturing an electrical cable having an integrally formed jacket and partitioned walls; 
         FIG. 3  illustrates an embodiment of a die assembly cap for manufacturing an electrical cable having an integrally formed jacket and partitioned walls; and 
         FIG. 4  illustrates an embodiment of a die assembly unit formed by combining the die assembly nozzle from  FIG. 2  with the die assembly cap from  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. 
     It should be understood that any one of the features of the invention may be used separately or in combination with other features. Other systems, methods, features, and advantages of the present invention will be or become apparent to one with skill in the art upon examination of the drawings and the detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present invention, and be protected by the accompanying claims. 
     The present disclosure is described below with reference to the Figures in which various embodiments of the present invention are shown. The subject matter of the disclosure may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. 
       FIG. 1  shows an end view of an embodiment of an electrical cable having an integrally formed jacket and walls. As shown in  FIG. 1 , the electrical cable  1  comprises a jacket  5 , the jacket  5  is comprised of a non-metallic material such as PVC. One skilled in the art will readily recognize that other compounds are contemplated for use in the cable  1 . The cable  1  further comprises one or more insulated conductors  30  and one or more bare grounding conductors  35 . The one or more insulated conductors  30  and the one or more bare grounding conductors  35  are separated by an integrally formed wall  10 . The integrally formed wall  10  extends from one portion of the jacket  5  to another portion of the jacket  5  and runs the length of the electrical cable  1 , thereby forming chambers within the electrical cable  1 . The integrally formed wall  10  is comprised of the same material as the jacket  5 . In one embodiment, the integrally formed wall  10  is formed in such a manner that a free space  15  exists between the insulated conductor  30 , the jacket  5 , and the integrally formed wall  10 . 
     In another embodiment, the integrally formed wall  10  is formed in such a manner that a free space  15  exists between the bare grounding conductor  35 , the jacket  5 , and the integrally formed wall  10 . As shown in  FIG. 1 , the cable  1  comprises three chambers, two insulated conductors  30 , and a bare grounding conductor  35 , wherein the first insulated conductor  30  is located in a first chamber, the bare grounding conductor  35  is located in a second chamber, and the second insulated conductor  35  is located in a third chamber. One skilled in the art will readily recognize that other constructions are contemplated for use in the cable  1 . For example, in another embodiment, the cable  1  comprises two chambers, a plurality of insulated conductors  30 , and a bare grounding conductor  35 , wherein the plurality of insulated conductors  30  are located in the first chamber and the bare grounding conductor  35  is located in the second chamber. 
       FIG. 2  shows an embodiment of a die assembly nozzle  50  for manufacturing an electrical cable having an integrally formed jacket and partitioned walls. As shown in  FIG. 2 , the die assembly nozzle  50  comprises a base  51 . The die assembly nozzle  50  further comprises one or more extrusion holes  55 . One skilled in the art will recognize that the extrusion holes  55  may be located in various locations and in varying quantities. For instance, the extrusion holes  55  may be located on a curved angled surface  60 . In one embodiment, the extruded non-metallic material proceeds along the curved angled surface  60  until it arrives at an extrusion tip  65 . The extrusion tip  65  is shaped in substantially the same manner as the cable  1 . Passing through the extrusion tip  65  are one or more wall channels  70 . The one or more wall channels  70  function to create the one or more integrally formed walls  10  in the cable  1  during the extrusion process. During the manufacture of the cable  1 , the one or more insulated conductors  30  and the one or more bare grounding conductors  35  are fed through the extrusion tip  65  and separated by the wall channels  70 . In one embodiment, the one or more wall channels  70  are formed and positioned such that the free space  15  exists between the insulated conductor  30 , the extrusion tip  65 , and the wall channel  70 . In another embodiment, the one or more wall channels  70  are located such that the free space  15  exists between the bare grounding conductor  35  and the wall channels  70 . 
       FIG. 3  shows an embodiment of a die assembly cap  100 . In one embodiment, the die assembly cap  100  connects to the die assembly nozzle  50  at the base  51  (shown in  FIG. 2 ). As shown in  FIG. 3 , the die assembly cap  100  comprises an opening  105 . The shape of the opening  105  corresponds to the shape of the cable  1 . In one embodiment, the die assembly cap  100  may have extrusion holes  55 , such that the non-metallic material, such as PVC, which will ultimately form the jacket  5  and integrally formed walls  10  can pass through the die assembly cap  100  and engage the curved angled surface  60  (shown in  FIG. 2 ). In one embodiment, the interior of the die assembly cap  100  is designed to mirror, and thus fit, the curved angled surface  60  thereby forming a funnel leading to the extrusion tip  65 . 
       FIG. 4  shows an embodiment of a die assembly unit  110 . The die assembly unit  110  comprises the die assembly cap  100  fitted over the die assembly nozzle  50 . The extrusion tip  65  fits within the opening  105 . A non-metallic material, such as PVC, which will ultimately form the jacket  5  and the integrally formed walls  10  is heated and extruded through the extrusion holes  55 . One skilled in the art will readily recognize that other non-metallic compounds are contemplated for use with the die assembly nozzle  50 . The extruded material proceeds along the funnel formed by the curved angled surface  60  and the interior of the die assembly cap  100  towards the extrusion tip  65 . At the extrusion tip  65  some of the extruded material passes through the wall channels  70  and some of the extruded material encases the extrusion tip  65 . As a result, the extruded material forms the jacket  5  and the integrally formed walls  10  such that the jacket  5  and the integrally formed walls  10  encapsulate the one or more insulated conductors  30  and the one or more bare grounding conductors  35 . 
     Different embodiments may be formed in a similar manner having different characteristics depending upon need, performance, or some other criteria. It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that the invention disclosed herein is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.