The present application claims priority to and incorporates by reference the entire contents of Japanese Patent Application No. 2015-244886 filed in Japan on Dec. 16, 2015.
1. Field of the Invention
The present invention relates to a crimp terminal.
2. Description of the Related Art
A crimp terminal is conventionally known including an electric wire connecting portion to be electrically connected to a core wire of an electric wire and a terminal connecting portion to be electrically connected to a counterpart terminal. In this crimp terminal, a coupling portion coupling the electric wire connecting portion and the terminal connecting portion is interposed therebetween. Japanese Patent Application Laid-open No. 2014-182957, Japanese Patent Application Laid-open No. 2014-182958, Japanese Patent Application Laid-open No. 2014-160591, and Japanese Patent Application Laid-open No. 2012-69449 disclose this kind of crimp terminals. This kind of crimp terminals is formed through a press process (cutting processing, bending processing, and the like) on a flat plate-shaped member. The plate-shaped member subjected to cutting processing includes a flat electric wire side plate-shaped portion that will be the electric wire connecting portion later by bending processing and the like, a flat terminal side plate-shaped portion that will be the terminal connecting portion later by bending processing and the like, and a flat coupling side plate-shaped portion that will be the coupling portion later by bending processing and the like. The electric wire side plate-shaped portion is formed as a U-shaped electric wire connecting portion including a bottom portion on which an electric wire is placed during crimping processing and two barrel pieces extending from both ends of the bottom portion so as to surround the electric wire by bending processing.
Some terminal connecting portions may be formed to have a box-shaped appearance such as female terminals. In this case, the terminal side plate-shaped portion is formed as the terminal connecting portion by forming two facing walls by bending processing and continuing bending processing and the like on the walls and the like. In this process, the two walls are bent in the respective same directions as the two barrel pieces of the U-shaped electric wire connecting portion. Given this situation, when the bending processing on the two walls and the bending processing on the two barrel pieces are simultaneously performed, bending processing on the coupling side plate-shaped portion can also be performed simultaneously with these pieces of bending processing, and two facing side walls of the coupling portion can be formed by the bending processing. However, when the bending processing of the two walls on the terminal side plate-shaped portion and the bending processing of the two barrel pieces on the electric wire side plate-shaped portion cannot be performed simultaneously, the coupling side plate-shaped portion is bent in such a manner as being dragged by one bending processing performed first of the two, and the coupling side plate-shaped portion is again bent in such a manner as being dragged by the following, other bending processing, whereby the two facing side walls of the coupling portion are formed. In this case, portions of the coupling side plate-shaped portion that will be the side walls later are pulled between the terminal side plate-shaped portion side and the electric wire side plate-shaped portion side during the first bending processing. Consequently, stress concentration occurs at these portions by a tensile force occurring therebetween.
In view of the foregoing circumstances, an object of the present invention is to provide a crimp terminal with reduced durability degradation.
In order to achieve the above mentioned object, a crimp terminal according to one aspect of the present invention includes a terminal connecting portion to be electrically connected to a counterpart terminal; an electric wire connecting portion to be electrically connected to an end of an electric wire placed on an inner wall face side by crimping processing; and a coupling portion that couples the terminal connecting portion and the electric wire connecting portion, wherein the electric wire connecting portion is sectioned into a bottom portion on which the end of the electric wire is placed during the crimping processing, a first barrel piece that is caused to extend from one end of the bottom portion to be wound around the end of the electric wire, and a second barrel piece that is caused to extend from another end of the bottom portion to be wound around the end of the electric wire, the electric wire connecting portion is formed with the first barrel piece and the second barrel piece facing each other by bending processing on both ends of a flat electric wire side plate-shaped portion that will be the electric wire connecting portion later after two facing walls are formed by bending processing on both ends of a flat terminal side plate-shaped portion that will be the terminal connecting portion later, the coupling portion is formed with one side wall connected to one of the walls and the first barrel piece and another side wall connected to another one of the walls and the second barrel piece by bending processing on both ends of a flat coupling side plate-shaped portion that will be the coupling portion later, the two side walls facing each other are formed by bending both ends of the coupling side plate-shaped portion in such a manner as being dragged by the bending processing on both ends of the terminal side plate-shaped portion and by bending both ends of the coupling side plate-shaped portion in such a manner as being dragged by the following bending processing on both ends of the electric wire side plate-shaped portion, and certain portions of the coupling side plate-shaped portion that will be the side walls later include at least one tensile force absorbing portion that absorbs a tensile force between a side of the terminal side plate-shaped portion and a side of the electric wire side plate-shaped portion occurring during the bending processing on both ends of the terminal side plate-shaped portion.
According to another aspect of the present invention, in the crimp terminal, it is preferable that the tensile force absorbing portion is formed in a bent shape stretching by the tensile force.
According to still another aspect of the present invention, in the crimp terminal, it is preferable that the tensile force absorbing portion has the bent shape of a bead shape or a rib shape protruding from an inner wall face side to an outer wall face side or from the outer wall face side to the inner wall face side at the certain portions and is caused to extend from at least partial free end at the certain portion toward the other certain portion.
According to still another aspect of the present invention, in the crimp terminal, it is preferable that the tensile force absorbing portion has a shape in which bending is released at the time of the end of the bending processing on both ends of the terminal side plate-shaped portion at earliest.
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.
The following describes an embodiment of a crimp terminal according to the present invention in detail based on the accompanying drawings. This embodiment does not limit this invention.
The following describes one embodiment of the crimp terminal according to the present invention based on
Numeral 1 in
Specifically, the crimp terminal 1 includes a terminal metal fitting 10 and a water stop member 20.
The terminal metal fitting 10 is the main part of this exemplary crimp terminal 1. This terminal metal fitting 10 is formed into a certain shape that can be connected to the counterpart terminal and the electric wire 50 by performing punching processing, bending processing, and the like on a conductive metal plate (a copper plate, for example) as a base material. As illustrated in
The terminal metal fitting 10 may be a male terminal or a female terminal so long as the appearance of the terminal connecting portion 11 is formed in a box shape. The present embodiment provides a female terminal as an example.
A direction along which the counterpart terminal is connected with this crimp terminal 1 (an insertion direction), which is a longitudinal direction of the crimp terminal 1, is defined as a first direction L. For the parallel arrangement direction of this crimp terminal 1, which will be described later, the width direction of the crimp terminal is defined as a second direction W. A direction orthogonal to both the first direction L and the second direction W, which is the height direction of the crimp terminal 1, is defined as a third direction H.
The electric wire connecting portion 12 is first formed in one plate shape (
This electric wire connecting portion 12 can be sectioned into the area of a bottom portion 14, the area of a first barrel piece 15, and the area of a second barrel piece 16 (
The first barrel piece 15 and the second barrel piece 16 may be formed such that the respective distances from the bases on the bottom portion 14 to the end faces of tips 15a and 16a will be the same length or formed such that the distance will be longer in the other than in the one. The present embodiment exemplifies the former. The first barrel piece 15 and the second barrel piece 16 may be wound around the end of the electric wire 50 while overlapping each other or may be folded back toward the bottom portion 14 to crimp the tips 15a and 16a onto the end of the electric wire 50 (what is called the B type crimp, for example). The present embodiment provides the water stop member 20 as described below and uses the former form. The first barrel piece 15 and the second barrel piece 16 of the present embodiment are each formed as one piece with a coupling crimp portion 12C interposed between a core wire crimp portion 12A and a sheath crimp portion 12B described below. However, this crimp terminal 1 may be one in which the barrel piece of the core wire crimp portion 12A and the barrel piece of the sheath crimp portion 12B are arranged spaced apart from each other, that is, one in which the core wire crimp portion 12A and the sheath crimp portion 12B are coupled to each other via the coupling portion of the bottom portion 14 (not illustrated) alone.
The end of the electric wire 50 is inserted from a U-shaped opening (an opening formed in between the end faces of the respective tips 15a and 16a) of the electric wire connecting portion 12 into a U-shaped inner space. For this purpose, so as to make the end of the electric wire 50 easy to be inserted, in the electric wire connecting portion 12, the spacing between the first barrel piece 15 and the second barrel piece 16 becomes wider from the bottom portion 14 toward the opening (the tips 15a and 16a).
Furthermore, this electric wire connecting portion 12 can be sectioned into the area of the core wire crimp portion 12A, the area of the sheath crimp portion 12B, and the area of the coupling crimp portion 12C (
The electric wire connecting portion 12 is provided with a core wire holding area (hereinafter, referred to as a “serration area”) 17 for holding the crimped distal-end core wire 51 on the inner wall face (the wall face on the side covering the electric wire 50) thereof (
The electric wire connecting portion 12 and the distal-end core wire 51 are required to be electrically connected to each other. For this reason, the entry of water to the gap therebetween may degrade durability, which is unfavorable. When the electric wire connecting portion 12 and the distal-end core wire 51 are formed of different kinds of metallic materials having different ionization tendencies (copper and aluminum or the like), for example, the entry of water to the gap therebetween can corrode, in particular, the aluminum side therebetween. Given this situation, this crimp terminal 1 is provided with the water stop member 20 for suppressing the entry of water to the gap between the electric wire connecting portion 12 and the distal-end core wire 51 (
The water stop member 20 is formed in a certain shape and is affixed to the inner wall face of the flat electric wire connecting portion 12 illustrated in
The terminal metal fitting 10 described above is formed through a press process (cutting processing, bending processing, and the like) on one flat metallic plate-shaped member. The plate-shaped member subjected to cutting processing includes a flat and rectangular terminal side plate-shaped portion 11x that will be subjected to bending processing and the like to be the terminal connecting portion 11 later, a flat and rectangular electric wire side plate-shaped portion 12x that will be subjected to bending processing and the like to be the electric wire connecting portion 12 later, and a flat and rectangular coupling side plate-shaped portion 13x that will be subjected to bending processing to be the coupling portion 13 later (
For the terminal side plate-shaped portion 11x, bending processing is performed on both ends in its second direction W, whereby two facing walls 11a are formed. The terminal connecting portion 11 is formed by the following bending processing and the like on the walls 11a and the like. The electric wire side plate-shaped portion 12x is formed with the serration area 17 and the like on the inner wall face side, and the water stop member 20 is then affixed thereto. Bending processing is performed on both ends in its second direction W with the water stop member 20 affixed thereto, whereby the electric wire side plate-shaped portion 12x is formed as the U-shaped electric wire connecting portion 12 including the bottom portion 14 on which the electric wire is placed during crimping processing and the two facing first and second barrel pieces 15 and 16 extending from both ends of the bottom portion 14 so as to surround the end of the electric wire 50. In the coupling side plate-shaped portion 13x, bending processing is performed on both ends in its second direction W, whereby two facing side walls 13a are formed. One side wall 13a connects one wall 11a and the first barrel piece 15. The other side wall 13a connects the other wall 11a and the second barrel piece 16.
In the terminal metal fitting 10 of the present embodiment, the one wall 11a and the first barrel piece 15 are bent in the same direction, whereas the other wall 11a and the second barrel piece 16 are bent in the same direction. In this terminal metal fitting 10, the bending processing on both ends of the terminal side plate-shaped portion 11x is performed before the process of affixing the water stop member 20 to the electric wire side plate-shaped portion 12x. In other words, in this terminal metal fitting 10, the bending processing on both ends of the terminal side plate-shaped portion 11x and the bending processing on both ends of the electric wire side plate-shaped portion 12x are not performed simultaneously. Consequently, in the coupling side plate-shaped portion 13x, the bending processing on both ends thereof is performed in such a manner as being dragged by the bending processing on both ends of the terminal side plate-shaped portion 11x, and the bending processing on both ends thereof is performed in such a manner as being dragged by the following bending processing on both ends of the electric wire side plate-shaped portion 12x, whereby the two side walls 13a are formed. In other words, in the coupling side plate-shaped portion 13x, the two walls 11a are formed by the bending processing on both ends of the terminal side plate-shaped portion 11x, the wall 11a sides on both ends are bent, the first and second barrel pieces 15 and 16 are then formed by the bending processing on both ends of the electric wire side plate-shaped portion 12x, and the first and second barrel pieces 15 and 16 sides on both ends are bent, whereby the two side walls 13a are formed. Given these circumstances, certain portions of the coupling side plate-shaped portion 13x that will be the side walls 13a later, during the first bending processing on the two walls 11a, are pulled between the wall 11a side that tends to bend and the electric wire side plate-shaped portion 12x side that tends to remain as the plate shape and is bent while being stretched by a tensile force during the process. Consequently, stress concentration occurs at the certain portions that will be the side walls 13a later. Such stress concentration may cause the strength degradation of the side walls 13a, degrade the durability of the coupling portion 13, and thus degrade the durability of the crimp terminal 1.
Given these circumstances, the present embodiment includes, in the certain portions of the coupling side plate-shaped portion 13x that will be the side walls 13a later, at least one tensile force absorbing portion 13b that absorbs the tensile force between a side of the terminal side plate-shaped portion 11x and a side of the electric wire side plate-shaped portion 12x occurring during the bending processing on both ends of the terminal side plate-shaped portion 11x (
The tensile force absorbing portion 13b is preferably formed in a shape in which the bending is released at the time of the end of the bending processing on both ends of the terminal side plate-shaped portion 11x at the earliest. With this structure, the crimp terminal 1 of the present embodiment can appropriately reduce the load on the coupling side plate-shaped portion 13x by the tensile force during the bending processing, can thereby appropriately relax the stress concentration, and can obtain an effect of further reducing durability degradation.
The tensile force absorbing portion 13b can be provided even when the bending processing on both ends of the electric wire side plate-shaped portion 12x is performed before the bending processing on both ends of the terminal side plate-shaped portion 11x. Even in this case, the crimp terminal 1 can obtain an effect similar to that of the form described above.
The crimp terminal 1 having passed through the above process is formed as a chained body 30 (hereinafter, referred to as a “terminal chained body”) in which a plurality of ones are arranged (
The following describes the terminal crimping device 100.
As illustrated in
The terminal supply device 101 pulls out the top crimp terminal 1 on the outer circumferential side of the terminal chained body 30 wound in a reel shape to feed the top crimp terminal 1 to the crimp position in succession. After completing the crimping of the top crimp terminal 1 onto the electric wire 50 and the cutting of the top crimp terminal 1 from the terminal chained body 30, the terminal supply device 101 feeds the new top crimp terminal 1 to the crimp position. This terminal supply device 101 repeats the operation in succession each time the crimping processing and the cutting processing are performed.
This terminal supply device 101 has a configuration well known in this technical field and includes a terminal feeding member 101a to be inserted into the terminal feeding holes 31a of the coupling piece 31 and a power transmission mechanism 101b that drives the terminal feeding member 101a by the power of the drive unit 103. The power transmission mechanism 101b is configured as a link mechanism operating in conjunction with the crimping operation (the up-and-down motion of a ram 114A and the like described below) of the crimping device 102. This exemplary terminal supply device 101 drives the terminal feeding member 101a in an up-and-down direction and a right-and-left direction in conjunction with the crimping operation of the crimping device 102 to feed the crimp terminal 1 to the crimp position.
The crimping device 102 performs the crimping of the fed crimp terminal 1 onto the electric wire 50 and the cutting of this crimp terminal 1 from the terminal chained body 30. For this purpose, this crimping device 102 includes a crimping machine 110 and a terminal cutting body 120.
The crimping machine 110 is a device that crimps the crimp terminal 1 fed to the crimp position onto the end of the electric wire 50, thereby crimping the crimp terminal 1 onto the electric wire 50. This exemplary crimping machine 110 crimps the first barrel piece 15 and the second barrel piece 16 of the crimp terminal 1 onto the distal-end core wire 51 and the sheath 52 of the electric wire 50, respectively, thereby crimping this crimp terminal 1 onto the electric wire 50. This crimping machine 110 includes a frame 111, a first mold 112 and a second mold 113 in pairs, and a power transmission mechanism 114.
The frame 111 includes a base 111A, an anvil support 111B, and a support 111C for the power transmission mechanism 114 (hereinafter, referred to as a “transmission unit support”). The base 111A is fixed onto a mounting base (not illustrated) on which the terminal crimping device 100 is mounted, for example. The anvil support 111B and the transmission unit support 111C are fixed onto the base 111A. The transmission unit support 111C is arranged behind (the right side in
The first mold 112 and the second mold 113 are arranged spaced apart from each other in the up-and-down direction and form a crimp forming mold that pinches the crimp terminal 1 and the end of the electric wire 50 arranged therebetween to crimp the crimp terminal 1 onto the end of the electric wire 50 (
The drive unit 103 transmits its power to the power transmission mechanism 114, thereby narrowing the gap between the first anvil 112A and the first crimper 113A and the gap between the second anvil 112B and the second crimper 113B during such crimping processing and widening the gap between the first anvil 112A and the first crimper 113A and the gap between the second anvil 112B and the second crimper 113B after the crimping processing. In this example, the second mold 113 is moved upward and downward relative to the first mold 112, thereby simultaneously moving the first crimper 113A and the second crimper 113B upward and downward relative to the first anvil 112A and the second anvil 112B, respectively. However, the first anvil 112A, the second anvil 112B, the first crimper 113A, and the second crimper 113B may be formed bodies individually formed; in this case, the drive unit 103 and the power transmission mechanism 114 may separately move the first crimper 113A and the second crimper 113B upward and downward. In this example, after the crimping of the core wire crimp portion 12A has started by the first anvil 112A and the first crimper 113A, the crimping of the sheath crimp portion 12B by the second anvil 112B and the second crimper 113B starts.
The power transmission mechanism 114 of the present embodiment transmits the power output from the drive unit 103 to the first crimper 113A and the second crimper 113B and includes the ram 114A, a ram bolt 114B, and a shank 114C as illustrated in
The ram 114A is a movable member supported in such a manner as being freely movable upward and downward relative to the ram support 111C2. The second mold 113 is fixed to this ram 114A. Given this situation, the first crimper 113A and the second crimper 113B can move upward and downward relative to the ram support 111C2 integrally with the ram 114A. This ram 114A is formed in a rectangular parallelepipedal shape, for example. This ram 114A is formed with a female screw portion (not illustrated). This female screw portion is formed on the inner peripheral face of a hole in the up-and-down direction formed from the inside of the ram 114A toward an upper end face.
The ram bolt 114B includes a male screw portion (not illustrated) to be screwed with the female screw portion of the ram 114A. Given this situation, the ram bolt 114B can move upward and downward relative to the ram support 111C2 integrally with the ram 114A. This ram bolt 114B includes a bolt head 114B1 arranged above the male screw portion. The bolt head 114B1 is formed with a female screw portion (not illustrated). The female screw portion is formed on the inner peripheral face of a hole in the up-and-down direction formed from the inside of the bolt head 114B1 toward an upper end face.
The shank 114C is a cylindrical, hollow member and includes a male screw portion 114C1 and a connection portion (not illustrated) at the respective ends. This male screw portion 114C1 of the shank 114C is formed in the lower portion of the hollow member and is screwed with the female screw portion of the bolt head 114B1 of the ram bolt 114B. Given this situation, the shank 114C can move upward and downward relative to the ram support 111C2 integrally with the ram 114A and the ram bolt 114B. The connection portion is connected to the drive unit 103.
The drive unit 103 includes a driving source (not illustrated) and a power conversion mechanism (not illustrated) that converts the drive power of the driving source into power in the up-and-down direction. The connection portion of the shank 114C is coupled to the output shaft of the power conversion mechanism. Given this situation, the first crimper 113A and the second crimper 113B move upward and downward relative to the ram support 111C2 integrally with the ram 114A, the ram bolt 114B, and the shank 114C by the output of the drive unit 103 (the output of the power conversion mechanism). Examples of the driving source include electric actuators such as electric motors, hydraulic actuators such as hydraulic cylinders, and pneumatic actuators such as air cylinders.
The relative position in the up-and-down direction of the first crimper 113A relative to the first anvil 112A and the relative position in the up-and-down direction of the second crimper 113B relative to the second anvil 112B can be changed by adjusting a screwed amount between the female screw portion of the bolt head 114B1 and the male screw portion 114C1 of the shank 114C. A nut 114D is screwed with the male screw portion 114C1 of the shank 114C above the ram bolt 114B and serves as what is called a lock nut together with the female screw portion of the bolt head 114B1. Given this situation, this nut 114D is tightened toward the ram bolt 114B after the completion of the adjustment of the relative positions, thereby enabling the first crimper 113A and the second crimper 113B to be fixed to the respective relative positions.
The first anvil 112A and the second anvil 112B are formed with recessed faces 112A1 and 112B1 recessed downward at the respective upper ends (
The first crimper 113A and the second crimper 113B are formed with recessed portions 113A1 and 113B1, respectively, recessed upward (
The crimp terminal 1 subjected to the crimping processing by this crimping machine 110 is cut off from the coupling piece 31 by the terminal cutting machine 120. The terminal cutting machine 120 pinches and cuts the connecting portion 32 of the crimp terminal 1 fed to the crimp position by two terminal cutting units and performs the cutoff simultaneously with the progress of the crimping process. The terminal cutting machine 120 is arranged at the front (the left side in
The terminal cutting machine 120 is well known in this technical field and includes a terminal cutting body 121, a pressing-down member 122, and an elastic member 123, for example. The terminal cutting body 121 is arranged so as to be able to slide on the front face of the second anvil 112B in the up-and-down direction. In this terminal cutting machine 120, the terminal cutting body 121 and the second anvil 112B are formed with respective terminal cutting units. The pressing-down member 122 is fixed to the ram 114A and moves upward and downward integrally with the ram 114A. This pressing-down member 122 is arranged above the terminal cutting body 121 and descends to press down the terminal cutting body 121. The elastic member 123 applies an upward biasing force to the terminal cutting body 121 and is formed of a spring or the like. When a pressing-down force from the pressing-down member 122 is released, this elastic member 123 returns the terminal cutting body 121 to an initial position in the up-and-down direction. In this terminal cutting machine 120, the pressing-down member 122 descends along with the descending of the second mold 113 during the crimping processing and presses down the terminal cutting body 121, thereby cutting the connecting portion 32 by the respective terminal cutting units and cutting off the crimp terminal 1 from the terminal chained body 30.
In the crimp terminal according to the embodiments, when the bending processing on both ends of the terminal side plate-shaped portion is performed, the tensile force absorbing portion stretches by the tensile force occurring between the side of the terminal side plate-shaped portion and the side of the electric wire side plate-shaped portion. Consequently, this crimp terminal reduces a load caused by the tensile force therebetween, can thereby relax the stress concentration at the certain portions that will be the side walls later, and can reduce the strength degradation of the side walls. Consequently, this crimp terminal reduces the strength degradation of the coupling portion even when the bending processing on the terminal side plate-shaped portion and the bending processing on the electric wire side plate-shaped portion cannot be performed simultaneously, and can thereby reduce durability degradation.
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.
Number | Date | Country | Kind |
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2015-244886 | Dec 2015 | JP | national |