Patent Publication Number: US-10763597-B2

Title: Crimp terminal having a groove for facilitating crimping workability and a water stop member

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application is a continuation application of International Application PCT/JP2016/086252, filed on Dec. 6, 2016, and designating the U.S., the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a crimp terminal. 
     2. Description of the Related Art 
     Conventionally, crimp terminals including an electric wire connection portion to be electrically connected to a core of an electric wire have been known. The crimp terminal is formed by subjecting a metal plate serving as base material to punching, bending, and the like. The electric wire connection portion is a U-shaped portion formed from a bottom and two opposed barrel pieces, and in a crimping process, the bottom and free ends of the barrel pieces are sandwiched by two dice, an interval between the dice is decreased, and each of the barrel pieces is bent toward the other barrel piece to roll the electric wire. Crimp terminals of this type are disclosed in Japanese Patent Application Laid-open No. 2014-182953, Japanese Patent Application Laid-open No. 2014-182957 and Japanese Patent Application Laid-open No. 2001-217013, for example. 
     The rigidity of a crimp terminal is increased depending on the plate thickness of a metal plate serving as base material. For example, when a crimp terminal is applied to an electric wire having a large wire diameter, the plate thickness of the base material is increased to enhance the rigidity of the entire crimp terminal in order to bear the weight of the electric wire, or the length of a barrel piece is increased in order to secure the amount of rolling around the electric wire to enhance the rigidity of an electric wire connection portion as a result. Thus, although the barrel piece in the electric wire connection portion is bent following the shape of a die on the free end side during a crimping process in general, the barrel piece is not bent following the shape of the die due to its rigidity, and there is a possibility that a desired crimping form for the electric wire cannot be achieved. Note that Patent Literature 3 above discloses a technology in which a barrel piece for rolling a tip core at an end portion of an electric wire and a barrel piece for rolling a coating at the end portion of the electric wire are individually provided, and a groove for facilitating bending during a crimping process is provided in the barrel piece for the coating. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a crimp terminal having excellent crimping workability. 
     A crimp terminal according to one aspect of the present invention includes a terminal connection portion electrically connected to a counterpart terminal; and a plate-shaped electric wire connection portion electrically connected to an end portion of an electric wire placed on an inner wall surface side by a crimping process during which the electric wire connection portion is sandwiched between a first die and a second die, wherein the electric wire connection portion includes a bottom on which the end portion of the electric wire is placed in the crimping process, and first and second barrel pieces that are extended from both ends of the bottom, respectively, and are rolled to a region from a tip core to a coating at an end portion of the electric wire by the crimping process, at least one of the first barrel piece and the second barrel piece has at least one straight groove portion which serves as a starting point of bending for the crimping process and which is formed along an axial direction of the end portion of the electric wire and over the region from the tip core to the coating at the end portion of the electric wire, and the groove portion is a low-rigidity site which is interposed between a high-rigidity site on the electric wire side and a high-rigidity site on the distal end side in the extending direction and has rigidity lower than rigidity of the high rigidity sites. 
     According to another aspect of the present invention, in the crimp terminal, it is preferable that the groove portion is provided closer to a distal end in the extending direction than the end portion of the electric wire placed on the bottom. 
     According to still another aspect of the present invention, in the crimp terminal, it is preferable that when the second barrel piece is extended longer than the first barrel piece, the groove portion is provided at the second barrel piece. 
     According to still another aspect of the present invention, it is preferable that the crimp terminal further includes a water stop member that is overlaid on and attached to at least the groove portion in the inner wall surface of the electric wire connection portion before the crimping process is performed, and is filled in the groove portion by the crimping process and left therein, so as to suppress entry of water into the electric wire connection portion after the crimping process is completed. 
     The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view illustrating a crimp terminal according to an embodiment, and illustrates a state before being connected to an electric wire; 
         FIG. 2  is a perspective view illustrating the crimp terminal after completion of crimping according to the embodiment; 
         FIG. 3  is a side view illustrating the crimp terminal after the completion of crimping according to the embodiment; 
         FIG. 4  is a perspective view illustrating a terminal fitting for the crimp terminal according to the embodiment, and illustrates a state before a water stop member is attached; 
         FIG. 5  is a top view illustrating the terminal fitting for the crimp terminal according to the embodiment, and illustrates a state before the water stop member is attached; 
         FIG. 6  is a diagram illustrating a cross-sectional part of an electric wire connection portion cut along the line X-X in  FIG. 3 ; 
         FIG. 7  is a top view illustrating the electric wire connection portion, and illustrates a state after the water stop member is attached; 
         FIG. 8  is a diagram for describing a terminal crimping device; 
         FIG. 9  is a perspective view for describing first and second dice; 
         FIG. 10  is a front view for describing the first and the second dice; 
         FIG. 11  is a diagram illustrating a part of a crimping process in a site cut along the line X-X in  FIG. 3 ; 
         FIG. 12  is a diagram illustrating a part of the crimping process in the site cut along the line X-X in  FIG. 3 ; 
         FIG. 13  is a diagram illustrating a part of the crimping process in the site cut along the line X-X in  FIG. 3 ; and 
         FIG. 14  is a diagram illustrating the crimping process in the site cut along the line X-X in  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A crimp terminal according to an embodiment of the present invention is described in detail below with reference to the drawings. The present invention is not limited by the embodiment. 
     Embodiment 
     A crimp terminal according to one embodiment of the present invention is described with reference to  FIG. 1  to  FIG. 14 . 
     Reference numeral  1  in  FIG. 1  to  FIG. 3  represents a crimp terminal in the present embodiment. The crimp terminal  1  is electrically connected to an electric wire  50 , and is electrically connected to a counterpart terminal (not shown) while being integrated with the electric wire  50 . In this case, in order to expose a predetermined length of a core  51  at an end portion of the electric wire  50 , a coating  52  is peeled off and removed by the length. The core  51  may be either an assembly of wires or a single wire like a coaxial cable. The crimp terminal  1  is crimped to the end portion of the electric wire  50  in order to be electrically connected to the electric wire  50 , thereby being electrically connected to the exposed tip core (hereinafter referred to simply as “tip core”)  51 . 
     The crimp terminal  1  in the present embodiment is exemplified as a crimp terminal including a terminal fitting  10  and a water stop member  20  in order to secure water-proof property. Note that the crimp terminal  1  may be formed only of the terminal fitting  10 . 
     The terminal fitting  10  is a principal part of the exemplified crimp terminal  1 . The terminal fitting  10  is obtained by subjecting a conductive metal plate (for example, a copper plate) serving as base material to punching, bending, and the like and by forming the resultant to have a predetermined shape allowing connection to a counterpart terminal or the electric wire  50 . As illustrated in  FIG. 4 ,  FIG. 5 , and others, the terminal fitting  10  has a terminal connection portion  11  to be electrically connected to a counterpart terminal and an electric wire connection portion  12  to be electrically connected to the electric wire  50 . The terminal connection portion  11  and the electric wire connection portion  12  are coupled to each other with a coupling portion  13  interposed therebetween. 
     The terminal fitting  10  may be either a male terminal or a female terminal. The terminal connection portion  11  is formed as a male type when the terminal fitting  10  is a male terminal, and is formed as a female type when the terminal fitting  10  is a female terminal. In the present embodiment, the terminal fitting  10  is exemplified as a female terminal. 
     In this case, in the crimp terminal  1 , the direction of connection (direction of insertion) to a counterpart terminal is defined as a first direction L as a longitudinal direction. Furthermore, a parallel arrangement direction described later of the crimp terminals  1  is defined as a second direction W as a width direction of the crimp terminal  1 . Furthermore, in the crimp terminal  1 , a direction orthogonal to each of the first direction L and the second direction W is defined as a third direction H as a height direction. 
     The electric wire connection portion  12  is first formed into a single plate ( FIG. 4  and  FIG. 5 ), and is formed into a U shape as the state immediately before being connected to the electric wire  50  ( FIG. 1 ). Then, the electric wire connection portion  12  is wound around the electric wire  50  in the state in which the end portion of the electric wire  50  is placed on the electric wire connection portion  12 . In this manner, the electric wire connection portion  12  is crimped to the end portion of the electric wire  50  and brought into contact with the tip core  51 . 
     The electric wire connection portion  12  can be sectioned into a region of a bottom  14 , a region of a first barrel piece  15 , and a region of a second barrel piece  16  ( FIG. 1  and  FIG. 5 ). The bottom  14  is a site serving as a bottom wall of the U-shaped electric wire connection portion  12 , and the end portion of the electric wire  50  is placed on the bottom  14  during a crimping process. The first and second barrel pieces  15  and  16  are sites serving as side walls of the U-shaped electric wire connection portion  12 , and are extended at both ends of the bottom  14  in the second direction W, respectively. In the U-shaped electric wire connection portion  12 , the first and second barrel pieces  15  and  16  extend from both ends of the bottom  14  so as to surround the end portion of the electric wire  50 . 
     The lengths of the first barrel piece  15  and the second barrel piece  16  refer to distances from the root on the bottom  14  side to end surfaces of distal ends (end portions on free end side)  15   a  and  16   a , respectively. The first barrel piece  15  and the second barrel piece  16  may be formed such that the lengths thereof are equal to each other, or may be formed such that one of the first barrel piece  15  and the second barrel piece  16  may be longer than the other barrel piece. The present embodiment employs the latter case. Thus, one of the respective distal ends  15   a  and  16   a  protrudes in the third direction H more than the other distal end in the U-shaped electric wire connection portion  12 . In the present exemplification, the second barrel piece  16  is extended from the bottom  14  to be longer than the first barrel piece  15 . Thus, in the electric wire connection portion  12 , a region in which the first barrel piece  15  and the second barrel piece  16  overlap with each other (hereinafter referred to as “overlap region”) is formed after the crimping process is completed (hereinafter referred to as “after the completion of the crimping process”) is formed ( FIG. 6 ). Specifically, the overlap region is a region in which an outer wall surface of the first barrel piece  15  and an inner wall surface of the second barrel piece  16  are opposed to each other after the completion of the crimping process. In other words, in the electric wire connection portion  12 , the first barrel piece  15  is a barrel piece to be wound around the end portion of the electric wire  50  on the inner side, and the second barrel piece  16  is a barrel piece to be wound around the end portion of the electric wire  50  on the outer side. Therefore, in the crimping process, the first barrel piece  15  is wound around an outer circumferential surface of the end portion of the electric wire  50 , and the second barrel piece  16  is wound so as to cover the end portion of the electric wire  50  and the first barrel piece  15  in this state from the outer circumferential surface side. In the electric wire connection portion  12 , the first barrel piece  15  and the second barrel piece  16  are swaged to the end portion of the electric wire  50  in this manner. 
     In this case, the end portion of the electric wire  50  is inserted in a U-shaped inner space from the side of a U-shaped opening (opening formed between end surfaces of the respective distal ends  15   a  and  16   a ) of the electric wire connection portion  12 . Thus, the electric wire connection portion  12  is formed such that an interval between the first barrel piece  15  and the second barrel piece  16  increases from the bottom  14  side toward the opening (distal ends  15   a  and  16   a ) in order to allow the end portion of the electric wire  50  to be easily inserted. 
     Furthermore, the electric wire connection portion  12  can be sectioned into a region of a core crimping portion  12 A, a region of a coating crimping portion  12 B, and a region of a coupling crimping portion  12 C ( FIG. 2  to  FIG. 5 ). The core crimping portion  12 A is a site to be crimped to the tip core  51 , and is continuous to the coupling portion  13 . The coating crimping portion  12 B is a site to be crimped to the coating  52  continuous to the root at the exposed part of the tip core  51 . The coupling crimping portion  12 C is a site which couples the core crimping portion  12 A and the coating crimping portion  12 B together and which is crimped to the end portion of the electric wire  50 . 
     In the electric wire connection portion  12 , a core holding region (hereinafter referred to as “serration region”)  17  for holding the crimped tip core  51  is provided on an inner wall surface of the electric wire connection portion  12  (wall surface on side to cover electric wire  50 ) ( FIG. 4  and  FIG. 5 ). The serration region  17  is disposed on the inner wall surface of the electric wire connection portion  12  in at least a part to be wound around the tip core  51 . The exemplified serration region  17  is formed so as to cover the entire tip core  51 . Specifically, the serration region  17  in the present embodiment is formed by arranging recesses, protrusions, or a combination of recesses and protrusions in a rectangular shape, and is used to increase a contact area between the electric wire connection portion  12  and the tip core  51  owing to the recesses or the protrusions to enhance adhesion strength therebetween. In the present exemplification, the rectangular serration region  17  is formed by recesses  17   a.    
     In this case, the electric wire connection portion  12  and the tip core  51  need to be electrically connected to each other. Thus, the entry of water in the region between the electric wire connection portion  12  and the tip core  51  is not preferable because durability may decrease. For example, in the case where the electric wire connection portion  12  and the core  51  are formed from dissimilar metal materials (such as copper and aluminum) having different ionization tendencies, the aluminum side may corrode due to the entry of water into the region between the electric wire connection portion  12  and the core  51 . As a solution, the crimp terminal  1  is provided with the water stop member  20  for suppressing the entry of water into the region between the electric wire connection portion  12  and the tip core  51  ( FIG. 7 ). The water stop member  20  is mainly made of a pressure-sensitive adhesive such as a modified acrylic pressure-sensitive adhesive and formed into a sheet. For example, a member obtained by permeating an adhesive to sheet-shaped non-woven fabric to exhibit pressure-sensitive adhesive effect on both sides of the sheet is used as the water stop member  20 . 
     The water stop member  20  is formed into a predetermined shape, and is then attached to the inner wall surface of the plate-shaped electric wire connection portion  12  illustrated in  FIG. 7 . The exemplified water stop member  20  has a first water stop portion  21 , a second water stop portion  22 , and a third water stop portion  23 . The first water stop portion  21  is a portion in which a water stop region is formed at least between an outer wall surface of the first barrel piece  15  and an inner wall surface of the second barrel piece  16  (that is, overlap region) after the completion of the crimping process, and suppresses the entry of water into the region between the electric wire connection portion  12  and the tip core  51  from between the outer wall surface of the first barrel piece  15  and the inner wall surface of the second barrel piece  16 . The second water stop portion  22  is a portion in which a water stop region is formed at least on the terminal connection portion  11  side with respect to the position of the tip of the tip core  51  located inward of the electric wire connection portion  12  after the completion of the crimping process, and is a region for suppressing the entry of water into the region between the electric wire connection portion  12  and the tip core  51  from the terminal connection portion  11  side. The third water stop portion  23  is a portion in which a water stop region is formed at least between the inner wall surface of the electric wire connection portion  12  (specifically, coating crimping portion  12 B) and the coating  52  after the completion of the crimping process, and is a region for suppressing the entry of water into the region between the electric wire connection portion  12  and the tip core  51  from between the inner wall surface of the electric wire connection portion  12  and the coating  52 . The water stop member  20  interrupts the communication between the end portion of the electric wire  50  and the outside in the electric wire connection portion  12 , and hence can suppress the entry of water into the region between the electric wire connection portion  12  and the tip core  51 . 
     The terminal fitting  10  described above is manufactured in a manner that a single metal plate serving as base material is subjected to a pressing process and processed to have the plate-shaped electric wire connection portion  12  illustrated in  FIG. 5 , and in a subsequent water stop member attachment process, the water stop member  20  is attached to the plate-shaped electric wire connection portion  12 . After that, the terminal fitting  10  is subjected to a bending process such that the terminal connection portion  11  is formed and the U-shaped electric wire connection portion  12  is formed. 
     The crimp terminals  1  subjected to the above-mentioned processes are formed as a chain body in which the crimp terminals  1  are arranged in plurality (hereinafter referred to as “terminal chain body”). The terminal chain body refers to a collection of the crimp terminals  1  that are arranged in parallel at equal intervals while being oriented to the same direction and are connected in a chain shape. In the terminal chain body, end portions of all the crimp terminals  1  on one side are connected to each other with a coupling piece  31 . For example, the coupling piece  31  is formed into a rectangular plate shape and is disposed at a predetermined interval from the electric wire connection portions  12  of all the crimp terminals  1 . For example, the bottom  14  of the electric wire connection portion  12  and the coupling piece  31  are connected to each other for each crimp terminal  1  through a rectangular plate-shaped connecting portion  32 . In the coupling piece  31 , through holes (hereinafter referred to as “terminal feed holes”)  31   a  used to feeding the terminal chain body to a crimping position of a terminal crimping device  100  are formed at equal intervals along a feeding direction of the terminal chain body. The thus formed terminal chain body is disposed in the terminal crimping device  100  while being wound into a reel (not shown). Then, the crimp terminal  1  is crimped to the electric wire  50 , and is thereafter cut off from the terminal chain body. 
     The terminal crimping device  100  is described. 
     As illustrated in  FIG. 8 , the terminal crimping device  100  includes a terminal supply device  101  configured to supply the crimp terminal  1  to a predetermined crimping position, a crimping device  102  configured to crimp the crimp terminal  1  to the electric wire  50  at the crimping position, and a driving device  103  configured to operate the terminal supply device  101  and the crimping device  102 . The terminal supply device  101  and the crimping device  102  are devices called applicator in the technical field. 
     The terminal supply device  101  pulls out the first crimp terminal  1  on the outer circumferential side of the terminal chain body rolled up into a reel, and sequentially supplies the crimp terminal  1  to a crimping position. The terminal supply device  101  crimps the first crimp terminal  1  to the electric wire  50  and cuts the resultant from the terminal chain body, and then supplies the new first crimp terminal  1  to the crimping position. The terminal supply device  101  repeats this operation sequentially for every crimping process and cutting process. 
     The terminal supply device  101  has a well-known configuration in the technical field, and includes a terminal feed member  101   a  to be inserted into the terminal feed hole  31   a  in the coupling piece  31  and a power transfer mechanism  101   b  configured to drive the terminal feed member  101   a  with power of the driving device  103 . The power transfer mechanism  101   b  is formed as a link mechanism configured to operate simultaneously with a crimping operation of the crimping device  102  (vertical movement of ram  114 A and the like described later). The exemplified terminal supply device  101  operates simultaneously with the crimping operation of the crimping device  102  to drive the terminal feed member  101   a  in the vertical direction and the horizontal direction, thereby supplying the crimp terminal  1  to the crimping position. 
     The crimping device  102  crimps the supplied crimp terminal  1  to the electric wire  50 , and cuts off the crimp terminal  1  from the terminal chain body. Thus, the crimping device  102  includes a crimping machine  110  and a terminal cutting machine  120 . 
     The crimping machine  110  is a device configured to swage the crimp terminal  1  supplied to the crimping position to the end portion of the electric wire  50  to crimp the crimp terminal  1  to the electric wire  50 . The exemplified crimping machine  110  crimps the crimp terminal  1  to the electric wire  50  by swaging the first barrel piece  15  and the second barrel piece  16  of the crimp terminal  1  to the tip core  51  and the coating  52  of the electric wire  50 , respectively. The crimping machine  110  includes a frame  111 , a first die  112  and a second die  113  that are paired, and a power transfer mechanism  114 . 
     The frame  111  includes a base  111 A, an anvil support  111 B, and a support for the power transfer mechanism  114  (hereinafter referred to as “transfer unit support”)  111 C. For example, the base  111 A is fixed onto a placement stage (not shown) on which the terminal crimping device  100  is to be placed. The anvil support  111 B and the transfer unit support  111 C are fixed onto the base  111 A. The transfer unit support  111 C is disposed behind (right side in  FIG. 8 ) and above (upper side in  FIG. 8 ) the anvil support  111 B. Specifically, the transfer unit support  111 C includes an upright portion  111 C 1  that is provided upright behind the anvil support  111 B and upward from the base  111 A, and a ram support portion  111 C 2  held on top of the upright portion  111 C 1 . The ram support portion  111 C 2  is a support portion configured to support the ram  114 A described later, and is disposed above the anvil support  111 B with a predetermined interval. 
     The first die  112  and the second die  113  are crimping dies that are arranged with an interval in the vertical direction and configured to sandwich the crimp terminal  1  and the end portion of the electric wire  50  arranged between the first die  112  and the second die  113  to crimp the crimp terminal  1  to the end portion of the electric wire  50  ( FIG. 9 ). The first die  112  is formed of two lower dies, and has a first anvil  112 A and a second anvil  112 B as the lower dies. The second die  113  is formed of two upper dies, and has a first crimper  113 A and a second crimper  113 B as the upper dies. The first anvil  112 A and the first crimper  113 A are arranged to be opposed to each other in the vertical direction, and crimp the U-shaped core crimping portion  12 A to the tip core  51  by narrowing the interval between the first anvil  112 A and the first crimper  113 A. Furthermore, the second anvil  112 B and the second crimper  113 B are arranged to be opposed to each other in the vertical direction, and crimp the U-shaped coating crimping portion  12 B to the coating  52  by narrowing the interval between the second anvil  112 B and the second crimper  113 B. 
     The driving device  103  transfers power thereof to the power transfer mechanism  114 , thereby decreasing the interval between the first anvil  112 A and the first crimper  113 A and the interval between the second anvil  112 B and the second crimper  113 B during the crimping process and increasing the interval between the first anvil  112 A and the first crimper  113 A and the interval between the second anvil  112 B and the second crimper  113 B after the crimping process. In the present exemplification, the second die  113  is moved vertically with respect to the first die  112  such that the first crimper  113 A and the second crimper  113 B are simultaneously moved vertically with respect to the first anvil  112 A and the second anvil  112 B. Note that the first anvil  112 A, the second anvil  112 B, the first crimper  113 A, and the second crimper  113 B may be compacts that are individually formed, and in this case, the driving device  103  and the power transfer mechanism  114  may be configured to vertically move the first crimper  113 A and the second crimper  113 B individually. In the present exemplification, after the crimping of the core crimping portion  12 A is started by the first anvil  112 A and the first crimper  113 A, the crimping of the coating crimping portion  12 B is started by the second anvil  112 B and the second crimper  113 B. 
     The power transfer mechanism  114  in the present embodiment is configured to transfer power output from the driving device  103  to the first crimper  113 A and the second crimper  113 B, and includes the ram  114 A, a ram bolt  114 B, and a shank  114 C as illustrated in  FIG. 8 . 
     The ram  114 A is a movable member supported by the ram support portion  111 C 2  so as to be freely movable vertically. The second die  113  is fixed to the ram  114 A. Thus, the first crimper  113 A and the second crimper  113 B can move vertically with respect to the ram support portion  111 C 2  while being integrated with the ram  114 A. For example, the ram  114 A is formed into a rectangular parallelepiped. A female thread portion (not shown) is formed on the ram  114 A. The female thread portion is formed on an inner circumferential surface of a vertical hole formed inward of the ram  114 A toward the upper end surface. 
     The ram bolt  114 B has a male thread portion (not shown) to be threaded with the female thread portion of the ram  114 A. Thus, the ram bolt  114 B can move vertically with respect to the ram support portion  111 C 2  while being integrated with the ram  114 A. Furthermore, the ram bolt  114 B has a bolt head  114 B 1  disposed above the male thread portion. A female thread portion (not shown) is formed on the bolt head  114 B 1 . The female thread portion is formed on an inner circumferential surface of a vertical hole formed inward of the bolt head  114 B 1  toward the upper end surface. 
     The shank  114 C is a columnar hollow member, and has a male thread portion  114 C 1  and a connection portion (not shown) at respective end portions. The male thread portion  114 C 1  of the shank  114 C is formed on the lower side of the hollow member, and is threaded with the female thread portion of the bolt head  114 B 1  of the ram bolt  114 B. Thus, the shank  114 C can move vertically with respect to the ram support portion  111 C 2  while being integrated with the ram  114 A and the ram bolt  114 B. The connection portion is connected to the driving device  103 . 
     The driving device  103  includes a drive source (not shown) and a power conversion mechanism (not shown) configured to convert drive power of the drive source into power in the vertical direction. The connection portion of the shank  114 C is coupled to an output shaft of the power conversion mechanism. Thus, the first crimper  113 A and the second crimper  113 B move vertically with respect to the ram support portion  111 C 2  while being integrated with the ram  114 A, the ram bolt  114 B, and the shank  114 C in response to the output of the driving device  103  (output of power conversion mechanism). As the drive source, an electric actuator such as an electric motor, a hydraulic actuator such as a hydraulic cylinder, and a pneumatic actuator such as an air cylinder are applicable. 
     In this case, a relative position of the first crimper  113 A in the vertical direction with respect to the first anvil  112 A and a relative position of the second crimper  113 B in the vertical direction with respect to the second anvil  112 B can be changed by adjusting a screwing amount of the female thread portion of the bolt head  114 B 1  and the male thread portion  114 C 1  of the shank  114 C. A nut  114 D is threaded with the male thread portion  114 C 1  of the shank  114 C above the ram bolt  114 B, and functions as what is called a locknut together with the female thread portion of the bolt head  114 B 1 . Thus, by fastening the nut  114 D to the ram bolt  114 B side after the adjustment of the above-mentioned relative positions is completed, the first crimper  113 A and the second crimper  113 B can be fixed at the relative positions. 
     At respective upper distal ends of the first anvil  112 A and the second anvil  112 B, concave surfaces  112 A 1  and  112 B 1  that are recessed downward are formed ( FIG. 9 ). The concave surfaces  112 A 1  and  112 B 1  are formed into arcs conforming to the shapes of the bottom  14  at the U-shaped core crimping portion  12 A and the U-shaped coating crimping portion  12 B, respectively. In the crimping machine  110 , the concave surfaces  112 A 1  and  112 B 1  serve as crimping positions. In the crimp terminal  1  that has been supplied with the bottom  14  facing downward, the bottom  14  of the core crimping portion  12 A is placed on the concave surface  112 A 1  at the upper end of the first anvil  112 A, and the bottom  14  of the coating crimping portion  12 B is placed on the concave surface  112 B 1  at the upper end of the second anvil  112 B. The first die  112  is supported by the anvil support  111 B in the state in which the concave surfaces  112 A 1  and  112 B 1  are exposed upward to the core crimping portion  12 A and the coating crimping portion  12 B. 
     In the first crimper  113 A and the second crimper  113 B, concave portions  113 A 1  and  113 B 1  that are recessed upward are formed, respectively ( FIG. 9  and  FIG. 10 ). The concave portions  113 A 1  and  113 B 1  are arranged to be opposed to the concave surfaces  112 A 1  and  112 B 1  of the first anvil  112 A and the second anvil  112 B, respectively, in the vertical direction. Each of the concave portions  113 A 1  and  113 B 1  has first and second wall surfaces  115  and  116  opposed to each other, and a third wall surface  117  that connects upper ends of the first and second wall surfaces  115  and  116 . Each of the concave portions  113 A 1  and  113 B 1  swages the first barrel piece  15  and the second barrel piece  16  while winding the first barrel piece  15  and the second barrel piece  16  around the end portion of the electric wire  50  in a manner that the first to third wall surfaces  115 ,  116 , and  117  are brought into contact with the first barrel piece  15  and the second barrel piece  16 . The concave portions  113 A 1  and  113 B 1  are formed such that such a swaging operation can be performed. 
     The first wall surface  115 , which first comes into contact with the first barrel piece  15 , has a receiving portion  115   a  and a rolling portion  115   b.    
     The receiving portion  115   a  is a wall surface to be first brought into contact with the first barrel piece  15 , and the distal end  15   a  of the first barrel piece  15  abuts the receiving portion  115   a  along with the lowering of the second die  113 . The receiving portion  115   a  is inclined so as to gradually approach the second wall surface  116  as the distance from the concave surfaces  112 A 1  and  112 B 1  of the first anvil  112 A and the second anvil  112 B increases (that is, toward the upper side). Thus, along with the lowering of the second die  113 , the first barrel piece  15  is pushed sequentially from the distal end  15   a  side toward the electric wire  50  while sliding on the receiving portion  115   a.    
     The rolling portion  115   b  is a wall surface for rolling the first barrel piece  15  pushed by the receiving portion  115   a  toward the end portion of the electric wire  50 . The rolling portion  115   b  has a planar vertical surface  115   b   1  that is extended upward from a boundary portion with the receiving portion  115   a , and an arc surface  115   b   2  that is continuous to the vertical surface  115   b   1 , for rolling the first barrel piece  15 , which has been slid along the vertical surface  115   b   1 , from the distal end  15   a  side toward the end portion of the electric wire  50 . The vertical surface  115   b   1  is a flat surface along the movement direction of the second die  113 . The arc surface  115   b   2  is a surface smoothly connected to the vertical surface  115   b   1 , and is formed into an arc toward the second wall surface  116 . In the present exemplification, because the third wall surface  117  is provided, the arc surface  115   b   2  is formed so as to smoothly connect the vertical surface  115   b   1  and the third wall surface  117  to each other. Owing to such a rolling portion  115   b , when the first barrel piece  15  reaches the arc surface  115   b   2  while sliding on the rolling portion  115   b  along with the lowering of the second die  113 , the first barrel piece  15  is rolled toward the end portion of the electric wire  50  sequentially from the distal end  15   a  side. 
     The second wall surface  116 , which first comes into contact with the second barrel piece  16 , has a receiving portion  116   a  and a rolling portion  116   b  similarly to the first wall surface  115 . 
     The receiving portion  116   a  is a wall surface to be first brought into contact with the second barrel piece  16 , and the distal end  16   a  of the second barrel piece  16  abuts the receiving portion  116   a  along with the lowering of the second die  113 . The receiving portion  116   a  is inclined so as to gradually approach the first wall surface  115  as the distance from the concave surfaces  112 A 1  and  112 B 1  of the first anvil  112 A and the second anvil  112 B increases (toward the upper side). Thus, along with the lowering of the second die  113 , the second barrel piece  16  is pushed sequentially from the distal end  16   a  side toward the electric wire  50  while sliding on the receiving portion  116   a.    
     The rolling portion  116   b  is a wall surface for rolling the second barrel piece  16  pushed by the receiving portion  116   a  toward the end portion of the electric wire  50 . The rolling portion  116   b  has a planar vertical surface  116   b   1  that is extended upward from a boundary portion with the receiving portion  116   a , and an arc surface  116   b   2  that is continuous to the vertical surface  116   b   1 , for rolling the second barrel piece  16 , which has been slid along the vertical surface  116   b   1 , from the distal end  16   a  side toward the end portion of the electric wire  50 . The vertical surface  116   b   1  is a flat surface along the movement direction of the second die  113 . The arc surface  116   b   2  is a surface smoothly connected to the vertical surface  116   b   1 , and is formed into an arc toward the first wall surface  115 . In the present exemplification, because the third wall surface  117  is provided, the arc surface  116   b   2  is formed so as to smoothly connect the vertical surface  116   b   1  and the third wall surface  117  to each other. Owing to such a rolling portion  116   b , when the second barrel piece  16  reaches the arc surface  116   b   2  while sliding on the rolling portion  116   b  along with the lowering of the second die  113 , the second barrel piece  16  is rolled toward the end portion of the electric wire  50  sequentially from the distal end  16   a  side. 
     The third wall surface  117  is formed as a flat surface orthogonal to the movement direction (vertical direction) of the second die  113  or an arc surface that smoothly connects the respective arc surfaces  115   b   2  and  116   b   2  of the rolling portions  115   b  and  116   b.    
     The second barrel piece  16  is longer than the first barrel piece  15 . Thus, along with the lowering of the second die  113 , the distal end  16   a  of the second barrel piece  16  moves to the third wall surface  117  while sliding on the second wall surface  116 , and moves to the first wall surface  115  while sliding on the third wall surface  117 . In response to the shift of the sliding-contact surface of the second barrel piece  16  on the second die  113  side, the second barrel piece  16  is wound around the first barrel piece  15  and the electric wire  50  while being rolled toward the electric wire  50 . In this case, the second barrel piece  16  pushes the first barrel piece  15  toward the electric wire  50  by the inner wall surface thereof, thereby assisting the rolling of the first barrel piece  15  toward the electric wire  50 . Thus, after the first barrel piece  15  is rolled toward the electric wire  50  by the arc surface  115   b   2 , the rolling is continued due to the force from the second barrel piece  16 , and the first barrel piece  15  is wound around the electric wire  50 . 
     The receiving portions  115   a  and  116   a  are formed into such shapes that the first barrel piece  15  and the second barrel piece  16  abut the receiving portions  115   a  and  116   a , respectively, at substantially the same time along with the lowering of the second die  113  ( FIG. 11 ). 
     The first barrel piece  15  and the second barrel piece  16  become less easily bent as the rigidity thereof becomes higher, and hence it is difficult to roll the first barrel piece  15  and the second barrel piece  16  toward the electric wire  50  at the rolling portions  115   b  and  116   b . For example, in the present embodiment, the second barrel piece  16  is longer than the first barrel piece  15 , and hence the second barrel piece  16  reaches the arc surface  116   b   2  of the rolling portion  116   b  earlier than the first barrel piece  15 . Thus, in the electric wire connection portion  12 , in the case where the second barrel piece  16  has too high rigidity to be bent at the arc surface  116   b   2 , for example, the second barrel piece  16  is not bent along with the lowering of the second die  113 , and an excessive load is applied to the bottom  14 , with the result that a crimping process cannot be performed in a desired crimping form for the end portion of the electric wire  50 . Furthermore, in the electric wire connection portion  12  in the present embodiment, the barrel piece of the core crimping portion  12 A and the barrel piece of the coating crimping portion  12 B are integrated together through the coupling crimping portion  12 C (that is, the first barrel piece  15  and the second barrel piece  16  are what is called an integrated barrel piece capable of rolling the tip core  51  and the coating  52  at the end portion of the electric wire  50 ), and hence the rigidity of the first barrel piece  15  and the second barrel piece  16  is high. Thus, in the electric wire connection portion  12 , the crimping workability for the end portion of the electric wire  50  may decrease in terms of this point. 
     In view of the above, in the present embodiment, at least one groove portion  18  that serves as a start point of bending of the second barrel piece  16  is provided in the inner wall surface of the electric wire connection portion  12  ( FIG. 4  and  FIG. 5 ). 
     The groove portion  18  is provided in the second barrel piece  16  along the first direction L (in other words, axial direction of end portion of electric wire  50  to be crimped). The groove portion  18  is a low-rigidity site which is interposed between a high-rigidity site on the electric wire  50  side and a high-rigidity site on the distal end  16   a  side and has rigidity lower than that of the high-rigidity sites. In the second barrel piece  16 , the rigidity of the groove portion  18  is lower than rigidity around the groove portion  18 , and hence the second barrel piece  16  starts to bend at the groove portion  18  as a starting point when force is applied to the bottom  14  and the distal end  16   a  from the first die  112  and the second die  113 . 
     The groove portion  18  is a straight groove that is extended along the first direction L between end portions of the electric wire connection portion  12  (end portion on coupling portion  13  side and end portion on connecting portion  32  side). In other words, the groove portion  18  is a straight groove that is formed along the first direction L and over the region from the tip core  51  to the coating  52  at the end portion of the electric wire  50 . The groove portion  18  may be extended to reach the end surfaces of the end portions of the electric wire connection portion  12 , or may be extended to positions on the inner side of the end surfaces. In the present exemplification, the latter case is taken as an example. In the case where the groove portions  18  are provided in plurality, the groove portions  18  are arranged in parallel with intervals therebetween in the inner wall surface of the electric wire connection portion  12 . In the present exemplification, a single groove portion  18  is formed in the inner wall surface of the electric wire connection portion  12  and in the second barrel piece  16 . 
     For example, the groove portion  18  may be a U-shaped groove obtained by hollowing out the cross section orthogonal to the extending direction of the groove portion  18  into a rectangular shape, or may be a V-shaped groove like a notch obtained by being hollowed out into a triangular shape. The groove width (in case of U-shaped groove) or an included angle of the V-shape (in case of V-shaped groove) and the groove depth of the groove portion  18  are set to such sizes that the groove portion  18  serves as a starting point of bending of the second barrel piece  16  due to force applied from the first die  112  and the second die  113  and that the second barrel piece  16  is not divided across the groove portion  18 . Furthermore, the groove portion  18  includes a portion whose plate thickness is smaller than that of the surrounding (high rigidity site on electric wire  50  side and high rigidity site on distal end  16   a  side). 
     For winding the second barrel piece  16  around the electric wire  50 , it is desired to bend the second barrel piece  16  on the distal end  16   a  side with respect to the electric wire  50  placed on the bottom  14 . Thus, the groove portion  18  is provided on the distal end  16   a  side with respect to the end portion of the electric wire  50  placed on the bottom  14  ( FIG. 11  to  FIG. 14 ). On the other hand, if the groove portion  18  is too close to the distal end  16   a  in the region on the distal end  16   a  side with respect to the electric wire  50 , the region of the high rigidity site on the electric wire  50  side is enlarged, and the groove portion  18  may be less likely to serve as a starting point of bending. Thus, in the case where the single groove portion  18  is provided, it is desired to provide the groove portion  18  at a center portion between the electric wire  50  and the distal end  16   a  in the region on the distal end  16   a  with respect to the electric wire  50  in the second barrel piece  16 . Then, in the case where a crimping process is not still performed in a desired crimping form for the end portion of the electric wire  50 , a plurality of the groove portions  18  only need to be provided in the region on the distal end  16   a  side with respect to the electric wire  50  in the second barrel piece  16 . In addition, it is desired to provide the groove portion  18  at a position at which the distal end  15   a  of the first barrel piece  15  is not hooked during the crimping process in order to secure a desired crimping form. 
     For example, in the electric wire connection portion  12 , the distal end  16   a  of the second barrel piece  16  reaches the arc surface  116   b   2  of the rolling portion  116   b  along with the lowering of the second die  113  ( FIG. 12 ), and the second barrel piece  16  starts to bend at the groove portion  18  as a starting point along with further lowering of the second die  113  ( FIG. 13 ). Thus, in the electric wire connection portion  12 , the first barrel piece  15  and the second barrel piece  16  can be wound around the end portion of the electric wire  50  by the crimping process using the first die  112  and the second die  113 . In  FIG. 14 , the process of crimping to the electric wire  50  is illustrated by steps, taking the coating crimping portion  12 B as an example. 
     The crimp terminal  1  subjected to the crimping process by the crimping machine  110  as described above is cut off from the coupling piece  31  by the terminal cutting machine  120 . The terminal cutting machine  120  is configured to cut the connecting portion  32  of the crimp terminal  1  supplied to the crimping position by sandwiching the connecting portion  32  with two terminal cutting portions, and performs the cutting simultaneously with the crimping step in progress. The terminal cutting machine  120  is disposed on the front side of the second anvil  112 B (left side in  FIG. 8 ). 
     The terminal cutting machine  120  is well known in the technical field, and includes, for example, a terminal cutting body  121 , a pressing member  122 , and an elastic member  123 . The terminal cutting body  121  is disposed so as to be slidable in the vertical direction along the front surface of the second anvil  112 B. In the terminal cutting machine  120 , a terminal cutting portion is formed on each of the terminal cutting body  121  and the second anvil  112 B. The pressing member  122  is fixed to the ram  114 A, and moves vertically together with the ram  114 A. The pressing member  122  is disposed above the terminal cutting body  121 , and lowers to push the terminal cutting body  121  downward. The elastic member  123  is configured to apply an upward biasing force to the terminal cutting body  121 , and is made of a spring member or the like. When a pushing force from the pressing member  122  is released, the elastic member  123  returns the terminal cutting body  121  to its initial position in the vertical direction. In the terminal cutting machine  120 , the pressing member  122  lowers along with the lowering of the second die  113  during the crimping process to push the terminal cutting body  121  downward, thereby cutting the connecting portion  32  at the corresponding terminal cutting portion and cutting off the crimp terminal  1  from the terminal chain body  30 . 
     As described above, in the crimp terminal  1  in the present embodiment, at least one of the first barrel piece  15  and the second barrel piece  16  is provided with at least one groove portion  18  that is formed along the first direction L (axial direction of end portion of electric wire  50  to be crimped). Thus, in the crimp terminal, the first barrel piece  15  or the second barrel piece  16  having the groove portion  18  can be easily bent in the crimping process by the first die  112  and the second die  113 , and hence the first barrel piece  15  and the second barrel piece  16  can be wound around the end portion of the electric wire  50  without applying an excessive load to the electric wire connection portion  12 . Consequently, the crimp terminal enables the crimping process in a desired crimping form for the end portion of the electric wire  50 , thus improving crimping workability. 
     In this case, in the electric wire connection portion  12  in the present embodiment, even the first barrel piece  15  may be hard to be bend due to its high rigidity. It is thus desired that in the electric wire connection portion  12  in this case, at least one groove portion  18  similar to that in the second barrel piece  16  be provided in the first barrel piece  15 . Furthermore, in the electric wire connection portion  12  in the present embodiment, the second barrel piece  16  is longer than the first barrel piece  15 , but in the case where the first barrel piece  15  and the second barrel piece  16  have equal lengths and have such high rigidity that makes it difficult for the first barrel piece  15  and the second barrel piece  16  to be bent in the crimping process using the first die  112  and the second die  113 , it is desired to provide at least one groove portion  18  described above in each of the first barrel piece  15  and the second barrel piece  16 . Furthermore, the place where at least one groove portion  18  is provided is not limited to the first barrel piece  15  or the second barrel piece  16  in which the core  51  side and the coating  52  side are integrated as in the present embodiment. At least one groove portion  18  may be provided to the barrel piece of the core crimping portion  12 A and the barrel piece of the coating crimping portion  12 B, which are formed separately. 
     Note that the groove portion  18  is provided on the inner wall surface side of the electric wire connection portion  12 , but may be provided on the outer wall surface side of the electric wire connection portion  12 . 
     Furthermore, the above-mentioned water stop member  20  may be overlaid on and attached to at least the groove portion  18  before a crimping process is performed. In the exemplified water stop member  20 , the first water stop portion  21  is overlaid on and attached to the groove portion  18  ( FIG. 7 ). It is desired that a part of the first water stop portion  21  be filled in the groove portion  18  by the crimping process and left therein, and the water stop member  20  be stayed inside and around the groove portion  18  even after the crimping process. Thus, for example, when the water stop member  20  is attached to the electric wire connection portion  12 , a pressure toward the electric wire connection portion  12  is applied to the water stop member  20 . In the present embodiment, the pressure is set to a magnitude that can push a part of the first water stop portion  21  into the groove portion  18 , and the groove width of the groove portion  18  is set to a size that allows a part of the first water stop portion  21  to enter the groove portion  18  due to the pressure. Consequently, after the completion of crimping, the water stop member  20  can be stayed at least inside the groove portion  18 , and the entry of water into the electric wire connection portion  12  from the groove portion  18  can be suppressed. Consequently, the crimp terminal  1  in the present embodiment can enhance the water stop performance by the water stop member  20  along with improvement of crimping workability by the groove portion  18 , and in addition, can further improve the water stop performance by the water stop member  20  filled in the groove portion  18 . 
     In the crimp terminal according to the present embodiments, the integrated first barrel piece or second barrel piece having the groove portion can be easily bent in a crimping process, and hence the first barrel piece and the second barrel piece can be wound around the end portion of the electric wire without applying an excessive load to the electric wire connection portion. Consequently, the crimp terminal enables the crimping process for the end portion of the electric wire in a desired crimping form, thus improving crimping workability. 
     Although the invention has been described with respect to specific embodiments for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the basic teaching herein set forth.