Patent Publication Number: US-9893439-B2

Title: Terminal fitting with wire connection portion

Description:
BACKGROUND 
     1. Field of the Invention 
     The present invention relates to a terminal fitting. 
     2. Description of the Related Art 
     A known technique forms a wire connecting portion to be connected to an end part of a wire, separately forms a part to be arranged in front of the wire connecting portion and then joins those as separately formed components. For example, Japanese Unexamined Patent Publication No. 2013-84505 discloses a terminal fitting described with a wire connecting portion to be connected to an end part of a wire. A rectangular tube that is to be arranged in front of the wire connecting portion is formed as a separate component for the purpose of reducing cost. The wire connecting portion is integrally formed with a resilient contact piece to be arranged inside the rectangular tube and is configured to resiliently contact a mating terminal fitting. The wire connecting portion including the resilient contact piece is made of copper alloy that is excellent in conductivity. However, the rectangular tube is made of relatively inexpensive stainless steel, thereby reducing material cost for the terminal fitting. The wire connecting portion and the rectangular tube are held in an assembled state by holding a holding piece provided on a rear end part of the rectangular tube in close contact with a part between the resilient contact piece and the wire connecting portion. 
     A large force tends to act on joint portions of the wire connecting portion and another constituent component in the terminal fitting as described above if the wire connected to a mating side vibrates. Thus, a countermeasure has been desired. 
     The present invention was completed based on the above situation and aims to provide a terminal fitting capable of preventing a large force from acting on joint portions of a wire connecting portion and another constituent component formed separately from the wire connecting portion. 
     SUMMARY 
     The invention is directed to a terminal fitting with a wire connecting portion to be connected to an end part of a wire, and another constituent component formed separately from the wire connecting portion and to be arranged in front of the wire connecting portion. The other constituent component includes a joint piece to be overlapped on the wire connecting portion and joined, and a part of the wire connecting portion behind a part to be crimped to a core of the wire is joined to the joint piece. 
     The wire connecting portion may include a barrel to be crimped to the end part of the wire, and the wire connecting portion may have a part to be joined to the joint piece and projecting rearwardly of the barrel. According to this configuration, the joint portions of the wire connecting portion and the other constituent component are displaced rearward of the barrel. Thus, the influence of the deformation of the barrel on the joint portions when the barrel portion is crimped can be reduced. 
     The barrel may be crimped to the end part of the wire arranged on an upper surface, and the joint piece is overlapped on an upper side of a bottom portion of the barrel and joined. According to this configuration, the barrel is crimped to the joint piece together with the wire. Thus, a force acting on the joint portions can be reduced further. 
     The wire connecting portion and the other constituent component may be joined by welding. According to this configuration, the structures of the joints can be simplified, for example, as compared to the case where joints provided with crimping pieces are joined. 
     The other constituent component may include a connecting body having a bolt insertion hole for bolting to a ground part. According to this configuration, in the terminal fitting bolted to the ground part, the joints of the wire connecting portion and the other constituent component are arranged on the ground part side. The wire is hardly bent toward the ground part side (joint portion side). Thus, a force acting on the joint portions can be reduced. 
     According to the present invention, since the joint portions of the wire connecting portion and the other constituent component formed separately from the wire connecting portion are arranged along the wire, the joint portions vibrate together with the wire. Thus, it is possible to prevent a large force from acting on the joint portions of the wire connecting portion and the other constituent component. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of a terminal fitting in an embodiment showing a state before a wire connecting portion and another constituent component are joined. 
         FIG. 2  is a perspective view showing the terminal fitting in a state where the wire connecting portion and the other constituent component are joined. 
         FIG. 3  is a plan view showing the terminal fitting in the state where the wire connecting portion and the other constituent component are joined. 
         FIG. 4  is a side view showing a state of connecting the terminal fitting to an end part of a wire. 
         FIG. 5  is a perspective view showing a state where the terminal fitting is connected to the end part of the wire. 
         FIG. 6  is a side view showing the state where the terminal fitting is connected to the end part of the wire. 
         FIG. 7  is a plan view showing the state where the terminal fitting is connected to the end part of the wire. 
         FIG. 8  is a bottom view showing the state where the terminal fitting is connected to the end part of the wire. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, one specific embodiment of the invention is described in detail with reference to  FIGS. 1 to 8 . 
     A terminal fitting T in this embodiment, as shown in  FIG. 1 , has a wire connecting portion  10  to be connected to an end part of a wire  30  and a separately formed other constituent component  20  to be arranged in front of the wire connecting portion  10 . The wire connecting portion  10  and the other constituent component  20  are formed by press-working a suitable metal plate material. In the following description, a left-front side (connection side to a mating side) and a right-back side (connection side to the wire  30 ) of  FIG. 2  are referred to as a front and a rear and upper and lower sides of  FIG. 2  are referred to as upper and lower sides in each constituent member. 
     The wire connecting portion  10  includes a barrel  11  to be crimped to the end part of the wire  30 . The barrel  11  is of an open barrel with crimping pieces  13  standing up from a bottom portion  12 . 
     The barrel  11  includes a wire barrel  11 A to be crimped to an exposed core  31  and an insulation barrel  11 B to be crimped to an end part of an insulation coating  32 . The crimping pieces  13  of the wire barrel  11 A and the crimping pieces  13  of the insulation barrels  11 B are respectively crimped to wrap around the core  31  and the insulation coating  32  of the wire  30 . Note that the wire barrel  11 A is in front of the insulation barrel  11 B. 
     The wire connecting portion  10  has a wire connection side joint portion  14  to which the other constituent component  20  is to be joined and that projects rearward of the insulation barrel  11 B. The wire connection side joint portion  14  is formed by causing the bottom portion  12  of the insulation barrel  11 B to project rearward and has a rectangular shape slightly longer in a width direction in a plan view (see  FIG. 8 ). 
     The other constituent component  20  includes a connecting body  22  having a bolt insertion hole  21  for bolting the constituent component  20  to a ground part. The connecting body  22  is in the form of a substantially circular annular flat plate with the substantially circular bolt insertion hole  21  formed in a central part. The rear edge of the connecting body  22  is formed into inclined edges  23  gradually inclined toward a rear end to narrow a width of the connecting body  22 , as shown in  FIG. 3 . 
     The other constituent component  20  has a joint piece  24  to be overlapped on the wire connecting portion  10  and joined to extend rearward from the rear end of the connecting body  22 . The joint piece  24  is integral with the connecting body  22  and extends rearward from a widthwise central part (between a pair of the inclined edges  23 ) of the connecting body  22 . The joint piece  24  is in the form of a substantially rectangular flat plate long and narrow in a front-rear direction. The entire other constituent component  20  including the joint piece  24  is in the form of a flat plate having no step. 
     A length (dimension in the front-rear direction) of the joint piece  24  is equivalent to a length of the wire connecting portion  10  including the wire connection side joint portion  14  (entire length of the wire connecting portion  10 ). Further, a width of the joint piece  24  is smaller than a diameter of the bolt insertion hole  21  and equivalent to a width of the bottom portion  12  of the wire connecting portion  10 . 
     An extending rear end part of the joint piece  24  serves as a joint portion to be overlapped on the wire connection side joint portion  14  and joined to form another component side joint portion  25  when the other constituent component  20  is overlapped on the wire connecting portion  10 . The other component side joint portion  25  has substantially the same shape as the wire connection side joint portion  14 . 
     Next, examples of an operation of manufacturing the terminal fitting T as described above and an operation of manufacturing the wire  30  with the terminal fitting by connecting the terminal fitting T to the end part of the wire  30  are described. 
     First, each of the wire connecting portion  10  and the other constituent component  20  is formed of an optimal material into an optimal shape. At this time, by using different materials for the wire connecting portion  10  and the other constituent component  20 , material cost can be suppressed. For example, the wire connecting portion  10  may be formed of copper or copper alloy and the other constituent component  20  may be formed of iron or iron alloy, which is a material less expensive than copper. Thus, material cost can be suppressed as compared to the case where the terminal fitting T is formed entirely of copper or copper alloy. 
     Further, by forming the wire connecting portion  10  of aluminum or aluminum alloy, it is possible to make electrolytic corrosion less likely to occur in the case of connection to the wire  30  in which the core  31  made of aluminum or aluminum alloy is covered with the insulation coating  32  (so-called aluminum wire). Forming the other constituent component  20  of iron or iron alloy, which is harder than aluminum, enables performance withstanding bolting to be provided. Further, a potential difference between iron and aluminum is smaller than that between iron and copper. Thus, electrolytic corrosion is less likely to occur even upon contact with aluminum or aluminum alloy. 
     Furthermore, by appropriately changing the plate thickness and shape of the wire connecting portion  10 , the wire connecting portion  10  can be crimped optimally to wires  30  having large diameters and wires  30  having small diameters. For example, for a wire  30  having a small diameter, a relatively thin plate material is used, the width of the bottom portion  12  is narrowed to conform to the diameter of the wire  30  and the crimping pieces  13  are made smaller to ensure high connection quality. Further, less material is wasted by making the wire connecting portion  10  smaller in accordance with the diameter. For a wire  30  having a large diameter, a relatively thick plate material is used, the width of the bottom portion  12  is expanded to conform to the diameter and the crimping pieces  13  are made larger so that high connection quality can be ensured. The plate thickness and shape of the other constituent component  20  can be set regardless of the wire connecting portion  10  to ensure the plate thickness and the shape necessary for bolting. Thus, connection quality both to the wire  30  and to the ground part can be enhanced. 
     Next, the wire connecting portion  10  and the other constituent component  20  are joined. 
     First, as shown in  FIGS. 1 and 2 , the other constituent component  20  is overlapped on an upper surface side of the wire connecting portion  10 . The joint piece  24  of the other constituent component  20  is overlapped on the upper surface of the wire connecting portion  10  (bottom portion  12  of the barrel  11 ). Then, the front end of the wire connecting portion  10  (front end of the wire barrel  11 A) comes into contact with the inclined edges  23  of the connecting body  22  to be positioned in the front-rear direction (see  FIG. 2 ). Further, the rear end of the other constituent component  20  and that of the wire connecting portion  10  are aligned, and the other component side joint portion  25  and the wire connection side joint portion  14  are overlapped entirely (see  FIG. 3 ). Then, the other component side joint portion  25  and the wire connection side joint portion  14  are joined by welding. In this way, the wire connecting portion  10  and the other constituent component  20  are integrated to complete the manufacturing operation of the terminal fitting T. 
     Subsequently, as shown in  FIGS. 4 and 5 , the terminal fitting T is connected to the end part of the wire  30 . The end part of the wire  30  is set on an upper surface of the terminal fitting T. Specifically, the end part of the wire  30  is placed on an upper side of the joint piece  24  so that the core  31  exposed at the end part of the wire  30  is located in the wire barrel  11 A and the insulation coating  32  is located in the insulation barrel  11 B. The crimping pieces  13  of the wire barrel  11 A and the crimping pieces  13  of the insulation barrel  11 B are crimped so that the crimping pieces  13  enclose the core  31  and the insulation coating  32  together with the joint piece  24  so that the wire barrel  11 A is crimped to the core  31  and the insulation barrel  11 B is crimped to the insulation coating  32 . 
     In the above way, the manufacturing operation of the wire  30  with terminal fitting is completed. Then, this terminal fitting T is connected, for example, to a predetermined ground part on a body of an automotive vehicle by bolting. In the terminal fitting T bolted to the ground part, the joint portions of the wire connecting portion  10  and the other constituent component  20  are arranged on a side of the wire  30  near the ground part. 
     The terminal fitting T of this embodiment includes the wire connecting portion  10  to be connected to the end part of the wire  30  and the other constituent component  20  formed separately from the wire connecting portion  10  and to be arranged in front of the wire connecting portion  10 , the other constituent component  20  includes the joint piece  24  to be overlapped on the wire connecting portion  10  and joined, and a part of the wire connecting portion  10  behind the part to be crimped to the core  31  of the wire  30  is joined to the joint piece  24 . According to this configuration, the joint portions of the wire connecting portion  10  and the other constituent component  20  are arranged along the wire  30 . Thus, the joint portions vibrate together with the wire  30 , and it is possible to prevent a large force from acting on the joint portions of the wire connecting portion  10  and the other constituent component  20 . 
     Further, the wire connecting portion  10  includes the barrel  11  to be crimped to the end part of the wire  30  and is provided with the wire connection side joint portion  14  (part to be joined to the joint piece  24 ) projecting rearward of the barrel  11 . According to this configuration, the joint portions of the wire connecting portion  10  and the other constituent component  20  are displaced rearward of the barrel  11 , the influence of the deformation of the barrel  11  on the joint portions when the barrel  11  is crimped can be reduced. 
     Further, the barrel  11  is crimped to the end part of the wire  30  arranged on the upper surface. Additionally, the joint piece  24  is overlapped on the upper side of the bottom portion  12  of the barrel  11  and joined. According to this configuration, since the barrel  11  is crimped to the joint piece  24  together with the wire  30 , a force acting on the joint portions can be reduced. 
     Further, the wire connecting portion  10  and the other constituent component  20  are joined by welding. According to this configuration, the structures of the joint portions can be simplified, for example, as compared to the case where joint portions provided with crimping pieces are joined. 
     Further, the other constituent component  20  includes the connecting body  22  having the bolt insertion hole  21  for bolting to the ground part. According to this configuration, in the terminal fitting bolted to the ground part, the joint portions of the wire connecting portion  10  and the other constituent component  20  are arranged on the ground part side. Since the wire  30  is hardly bent toward the ground part side (joint portion side), a force acting on the joint portions can be reduced. 
     The invention is not limited to the above described and illustrated embodiment. For example, the following embodiments also are included in the scope of the invention. 
     Although the barrel  11  of the wire connecting portion  10  is of the open barrel type in the above embodiment, there is no limitation to this. For example, the barrel of the wire connecting portion may be of a closed barrel type. 
     Although the wire connecting portion  10  includes the barrel  11  to be crimped to the end part of the wire  30  in the above embodiment, there is no limitation to this. For example, the wire connecting portion may include an insulation displacement blade with which the core of the wire is to be pressed into contact. 
     Although the wire connecting portion  10  is provided with the wire connection side joint portion  14  and the joint piece  24  is joined behind the barrel  11  in the above embodiment, there is no limitation to this. The joint piece has only to be joined to a part of the wire connecting portion behind the part to be crimped to the core of the wire. For example, the joint piece of the other constituent component may be joined to the bottom portion of the insulation barrel without providing the wire connection side joint portion. 
     Although the joint piece  24  is overlapped on the upper side of the bottom portion  12  of the barrel  11  and joined in the above embodiment, there is no limitation to this and the joint piece may be overlapped on a lower side of the bottom portion of the barrel and joined. 
     Although the wire connecting portion  10  and the other constituent component  20  are joined by welding in the above embodiment, there is no limitation to this. For example, the joint portions may be provided with crimping pieces and joined or crimping by the crimping pieces may be performed in addition to welding. 
     Although the other constituent component  20  includes the connecting body  22  having the bolt insertion hole  21  for bolting to the ground part in the above embodiment, there is no limitation to this and the other constituent component may be in any form provided that the other constituent component is to be arranged in front of the wire connecting portion. For example, the other constituent component may be a female-side tubular connecting portion into which a tab of a mating terminal fitting is to be inserted and connected, a male-side connecting portion that includes a tab, or the like. 
     Although the other component side joint portion  25  and the wire connection side joint portion  14  are joined by welding in the above embodiment, welded parts are not limited to these and welding may be performed in a wider range where the joint piece and the wire connecting portion are overlapped. 
     LIST OF REFERENCE SIGNS 
     
         
         T . . . terminal fitting 
           10  . . . wire connecting portion 
           11  . . . barrel 
           12  . . . bottom portion 
           14  . . . wire connection side joint portion 
           20  . . . another constituent component 
           21  . . . bolt insertion hole 
           22  . . . connecting body 
           24  . . . joint piece 
           30  . . . wire 
           31  . . . core