TERMINAL CONNECTING METHOD AND TERMINAL
20190165492 ยท 2019-05-30
Assignee
Inventors
Cpc classification
H01R43/0249
ELECTRICITY
H01R43/0263
ELECTRICITY
International classification
Abstract
A terminal connecting method includes setting a conductor having a plurality of strands on an upper surface of a bottom portion of an electric wire crimping part of a terminal, caulking the conductor in a manner to cover the conductor, and thereby crimping the conductor by a caulking portion and a connecting caulking portion extended from the bottom portion, and rotating and pressing a friction stir tool into a stir welding area in a part in which the conductor is crimped by the connecting caulking portion, and performing friction stir welding, after caulking and crimping.
Claims
1. A terminal connecting method comprising: setting a conductor having a plurality of strands on an upper surface of a bottom portion of an electric wire crimping part of a terminal; caulking the conductor in a manner to cover the conductor, and thereby crimping the conductor by a caulking portion and a connecting caulking portion extended from the bottom portion; and rotating and pressing a friction stir tool into a stir welding area in a part in which the conductor is crimped by the connecting caulking portion, and performing friction stir welding, after caulking and crimping.
2. The terminal connecting method according to claim 1, wherein, in the performing friction stir welding, a moving stir operation in which the friction stir tool is moved along the bottom portion is performed, after rotating and pressing the friction stir tool into the stir welding area.
3. The terminal connecting method according to claim 1, wherein, in the performing friction stir welding, the terminal is fitted into and held by a holding recessed portion formed in a jig.
4. The terminal connecting method according to claim 1, wherein the conductor is a bundle of the plurality of strands exposed in one end portions of a plurality of electric wires in which insulating coating are peeled off respectively.
5. The terminal connecting method according to claim 1, wherein the plurality of strands are made of aluminum or aluminum alloy.
6. A terminal comprising: a bottom portion on which a conductor having a plurality of strands is set; and a conductor caulking portion and a connecting caulking portion extended from the bottom portion and respectively caulked in a manner to cover the conductor so as to crimp the conductor, wherein the conductor caulking portion in which the conductor is crimped, includes a stir welding area into which a friction stir tool is rotated and pressed and in which friction stir welding is performed.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0025]
[0026]
[0027]
[0028]
[0029]
[0030]
[0031]
[0032]
DETAILED DESCRIPTION
[0033] Description is given below of embodiments according to the invention.
First Embodiment
[0034]
[0035] As shown in
[0036] The electric wire 20, as shown in
[0037] The terminal 10 is a terminal which, as shown in
[0038] The electric wire crimping part 12 includes a bottom portion 14, a pair of conductor caulking portions 16 respectively extended from both side edges of the bottom portion 14, a pair of coating caulking portions 18 formed continuously with the rear of the conductor caulking portions 16, and a connecting caulking portion 19 formed continuously with the front of the conductor caulking portions 16. The electric wire crimping part 12 includes an area where the connecting caulking portion 19 is formed, which is referred to as a stir welding area A. Here, the terminal connecting method of the present embodiment may be a terminal connecting method for connecting a terminal, whose electric wire crimping part 12 excludes the coating caulking portions 18 but includes only the conductor caulking portions 16 and connecting caulking portions 19, to an electric wire.
[0039] Also, serrations (recessed portions) 15 are formed in the inner surfaces of the conductor caulking portions 16 and the upper surface of the bottom portion 14 corresponding thereto. In the first embodiment, three serrations 15 are formed side by side at intervals in the extending direction (the left-and-right direction, in
[0040] The partner connecting part 11 is formed in a substantially rectangular shape having a mounting hole 13 through which, for example, bolts can be inserted, while the partner connecting part 11 can be connected to a partner terminal by bolts and nuts. Here, the shape of the partner connecting part 11 is not limited to the configuration of the present embodiment, but other shapes such as a circular shape can also be employed.
[0041] Next, description is given of the terminal connecting method according to the first embodiment.
[0042] The terminal connecting method of the first embodiment includes a conductor crimping step and a frictionally welding step.
(Conductor Crimping Step)
[0043] Firstly, in the conductor crimping step, as shown in
[0044] In the first embodiment, the front end of the conductor 23 exposed to the end portion of the electric wire 20 is placed on such portion of the upper surface of the bottom portion 14 as corresponds to the connecting caulking portions 19, and the vicinity of the above front end is placed on such portion of the upper surface of the bottom portion 14 as includes the serrations 15. Also, the front end of the insulating coating 24 in the end portion of the electric wire 20 is placed on such portion of the upper surface of the bottom portion 14 as corresponds to the coating caulking portions 18.
[0045] And, as shown in
[0046] The serrations 15 formed in the conductor caulking portions 16, when the conductor caulking portions 16 are caulked, bite into the conductor 23, whereby they break oxide films formed on the surfaces of the strands 21 of the electric wire 20 having a relatively smaller diameter and thus can lower the electrical contact resistance.
(Frictionally Welding Step)
[0047] Next, in the frictionally welding step, as shown in
[0048] The friction stir tool 51 of the first embodiment, as shown in
[0049] Also, referring to the friction stir tool 51, for example, by mounting it on a motor 50 capable of moving in the X-, Y- and Z-axis directions (in the fore-and-rear, left-and-right and up-and-down directions), or by using it together with a vertically movable motor 50 and a horizontally movable work table, or by mounting it on a motor 50 fixed to the tip end of a multi-axis robot arm, the friction stir tool 51 is preferably capable of moving relatively to the stir welding area A of the conductor 23 crimped to the terminal 10 in the X-, Y- and Z-axis directions.
[0050] In a specific frictionally welding procedure, firstly, as shown in
[0051] And, as shown in
[0052] After a certain period of time, the friction stir tool 51 bitten into the stir welding area A is lifted and is removed from the stir welding area A. Thus, as shown in
[0053] The above friction stir operation of the friction stir tool 51 is carried out in each of the pair of connecting caulking portions 19. Accordingly, as shown in
[0054] Here, in the frictionally welding step, a pair of friction stir connection portions 33 may also be formed simultaneously in the stir welding area A of the terminal 10 by a pair of friction stir tools 51.
[0055] Also, after the friction stir connection portions 33 are formed in the friction welding step, the periphery of the conductor 23 crimped to the electric wire crimping part 12 is preferably sealed with a sealant. Covering of the exposed portion of the conductor 23 with the sealant can prevent water from entering the terminal 10 from outside and coming into contact with the conductor exposed portion. This can suppress occurrence of galvanic corrosion in the aluminum- or aluminum alloy-made conductor 23 crimped to the copper- or copper alloy-made terminal 10.
[0056] Next, description is given of the operation of the terminal connecting method and terminal according to the first embodiment.
[0057] According to the terminal connecting method and terminal of the first embodiment, in the stir welding area A of the terminal 10, a portion of the terminal 10 and the plurality of strands 21 are allowed to flow plastically by the friction stir tool 51 and thus are frictionally stirred and connected together. Due to this, films such as oxide films formed on the surfaces of the strands 21 of the conductor 23 are broken and thus the strands 21 are allowed to be connected together, and the thus-connected strands are integrated with the terminal 10, thereby enhancing the electrical connection reliability. Also, since they are frictionally stirred and connected together in the stir welding area A which is a crimping portion formed by the connecting caulking portion 19 different from the conductor caulking portion 16, the fixing force of the conductor caulking portion 16 to the conductor 23 cannot be lowered. That is, since the conductor 23 is mechanically connected in the conductor caulking portion 16 and the conductor 23 is mechanically and electrically in the stir welding area A, the conductor 23 can be connected to the terminal 10 stably. Thus, when a portion of the terminal 10 and the plurality of strands 21 are frictionally stirred and connected together in the stir welding area A, an adverse effect on the conductor caulking portion 16 can be eliminated. Accordingly, the electrical contact resistance can be reduced without lowering the fixing force of the terminal 10 to the conductor 23.
[0058] Also, since a portion of the terminal 10 and the plurality of strands 21 of the conductor 23 are frictionally stirred and connected together in the stir welding area A by the friction stir tool 51 having a simple configuration capable of rotation, expensive ultrasonic equipment is not required and thus the manufacturing cost can be reduced.
[0059] Also, according to the terminal connecting method and terminal of the first embodiment, since the electric wire 20 composed of an aluminum electric wire and terminal 10 are crimped to each other, strong oxide films exist on the surfaces of the strands 21 made of aluminum or aluminum alloy, which can provide an inhibitory factor in reducing the electrical resistance. However, since the oxide films formed on the surfaces of the strands 21 are broken by the frictionally welding operation, the terminal 10 and electric wire 20 can be connected together with small electrical connection resistance.
[0060] Here, in the first embodiment, in the frictionally welding step, after the friction stir tool 51 is lowered and bitten into the stir welding area A to allow the connecting caulking portions 19 and conductor 23 to flow plastically, the friction stir tool 51 is removed. However, alternatively, the friction stir tool 51 may also be removed after execution of a moving stir operation by the friction stir tool 51 in which the friction stir tool 51 bitten into the stir welding area A is moved in a direction along the bottom portion 14, namely, in the horizontal direction to allow the connecting caulking portions 19 and conductor 23 to flow plastically further.
[0061] Next, description is given of various examples of movements in the moving stir operation in which the friction stir tool 51 is moved in a direction along the bottom portion 14, namely, in the horizontal direction to frictionally stir the connecting caulking portions 19 and conductor 23.
Movement Example 1
[0062] As shown in
Movement Example 2
[0063] As shown in
Movement Example 3
[0064] As shown in
Movement Example 4
[0065] As shown in
[0066] In this manner, in the frictionally welding step, after friction stir tool 51 is lowered and is bitten into the stir welding area A, by executing the moving stir operation in which the friction stir tool 51 is moved in a direction along the bottom portion 14, that is, in the horizontal direction, the connecting caulking portions 19 and conductor 23 are allowed to flow plastically in a wide range in the stir welding area A to thereby form the friction stir connection portions 33. This can further enhance the electrical connection reliability in the stir welding area A.
[0067] Here, when executing the above moving stir operation, with the movement of the friction stir tool 51, a laterally going large load is applied to the terminal 10. Thus, as shown in
[0068] In this way, when the stir welding area A of the terminal 10 is frictionally stirred by the friction stir tool 51, by fixing the terminal 10 using the jig 35, the friction stir operation can be performed stably and smoothly. Also, the deformation of the terminal 10 and the opening of the connecting caulking portions 19 due to execution of the friction stir operation can be suppressed.
[0069] Here, in the first embodiment, the friction stir tool 51 is bitten into the stir welding area A from the connecting caulking portion 19 side to stir the area frictionally. However, the friction stir tool 51 may also be bitten into the stir welding area A from the bottom portion 14 side.
[0070] Specifically, as shown in
[0071] In this case as well, when performing the frictionally welding step including the moving stir operation, as shown in
[0072] Here, even when performing a frictionally welding step excluding the moving stir operation, the terminal 10 may be fitted into and held by the holding recessed portion 36 of the jig 35. In this way, by allowing the jig 35 to hold the terminal 10, the posture of the terminal 10 when the friction stir tool 51 is bitten therein can be stabilized, and thus the frictionally welding step can be performed smoothly.
Second Embodiment
[0073]
[0074] As shown in
[0075] In each of the electric wires 20A, as shown in
[0076] Here, in the four electric wires 20A, the conductors 23A may be composed of only aluminum electric wires made of aluminum or aluminum alloy, or the conductors 23A may be composed of a combination of copper electric wires made of copper or copper alloy and aluminum electric wires.
[0077] The terminal 10A, similarly to the terminal 10 of the first embodiment, is formed by molding a plate-shaped member made of copper or copper alloy by mold press working or the like, and includes a partner connecting part 11 and an electric wire crimping part 12 formed integrally with the partner connecting part 11.
[0078] Next, description is given of the terminal connecting method of the second embodiment.
(Conductor Crimping Step)
[0079] Firstly, in the conductor crimping step, as shown in
[0080] In the second embodiment, the front ends of the bundles of core wires composed of the conductors 23A exposed to the terminal portions of the electric wires 20A are placed on the upper surface of the bottom portion 14 corresponding to the connecting caulking portions 19, and the vicinities of the front ends are placed on the upper surface of the bottom portion 14 where the serrations 15 formed. And, the front ends of the insulating coatings 24 in the end portions of the electric wires 20A are placed on the upper surface of the bottom portion 14 corresponding to the coating caulking portions 18. And, the conductor caulking portions 16 and connecting caulking portions 19 are caulked in a manner to cover the bundles of the core wires composed of the four conductors 23A and are crimped to the conductors 23A, and the coating caulking portions 18 are caulked in a manner to cover the front ends of the insulating coatings 24 and are crimped to the insulating coatings 24.
[0081] Since the conductor caulking portions 16 of the terminal 10A are bitten into the conductors 23A when they are caulked, the serrations 15 formed in the conductor caulking portions 16 can break oxide films formed on the surfaces of the strands 21 of the four joint-connected electric wires 20A, thereby lowering the electrical contact resistance.
(Frictionally Welding Step)
[0082] Next, in the frictionally welding step, similarly to the terminal connecting method of the first embodiment, using the friction stir tool 51, as shown in
[0083] Here, in the second embodiment as well, in the frictionally welding step, there may be performed a moving stir operation in which the friction stir tool 51 bitten into the stir welding area A is moved in a direction along the bottom portion 14 (which is the horizontal direction). When performing the frictionally welding step including this moving stir operation, the terminal 10A is fitted into and held by the holding recessed portion 36 of the jig 35 fixed to the work table 60 (see
[0084] Also, in the second embodiment as well, the friction stir tool 51 may be bitten into the terminal 10A held with the bottom portion 14 facing upward from the bottom portion 14 side in the stir welding area A to frictionally stir the strands and terminal (see
[0085] Next, description is given of the operations of the terminal connecting method and terminal according to the second embodiment.
[0086] According to the terminal connecting method and terminal of the second embodiment, in addition to operation effects similar to the terminal connecting method and terminal according to the first embodiment, by frictionally welding the strands 21 in the bundles of the core wires exposed to the terminal portions of the plurality of electric wires 20A and a portion of the terminal 10A, there is provided an operation effect that the plurality of electric wires 20A can be connected to the terminal 10A stably and easily.
[0087] Therefore, according to the terminal connecting method and terminal of the above embodiments, the electrical contact resistance with the conductors 23, 23A can be lowered without reducing the fixing force to the conductors 23, 23A.
[0088] The invention is not limited to the above embodiments but mutual combinations of the respective configurations of the embodiments, and changes and applications made by a person skilled in the art based on the description of the specification and well-known technology are also included within the scope of seeking protection of the invention.
[0089] Here, the characteristics of the embodiments of the terminal connecting method and terminal according to the above-mentioned invention are briefly summarized and are listed in the following configurations [1] to [6].
[1] A terminal connecting method comprising:
[0090] setting a conductor (23, 23A) having a plurality of strands (21) on an upper surface of a bottom portion (14) of an electric wire crimping part (12) of a terminal (10, 10A);
[0091] caulking the conductor (23, 23A) in a manner to cover the conductor (23, 23A), and thereby crimping the conductor (23, 23A) by a caulking portion (16) and a connecting caulking portion (19) extended from the bottom portion (14); and
[0092] rotating and pressing a friction stir tool (51) into a stir welding area (A) in a part in which the conductor (23, 23A) is crimped by the connecting caulking portion (19), and performing friction stir welding, after caulking and crimping.
[2] The terminal connecting method according to the above configuration [1],
[0093] wherein, in the performing friction stir welding, a moving stir operation in which the friction stir tool (51) is moved along the bottom portion (14) is performed, after rotating and pressing the friction stir tool (51) into the stir welding area (A).
[3] The terminal connecting method according to the above configuration [1] or [2],
[0094] wherein, in the performing friction stir welding, the terminal (10) is fitted into and held by a holding recessed portion (36) formed in a jig (35).
[4] The terminal connecting method according to any one of the above configurations [1] to [3],
[0095] wherein the conductor (23A) is a bundle of the plurality of strands (21) exposed in one end portions of a plurality of electric wires (20A) in which insulating coating (24) are peeled off respectively.
[5] The terminal connecting method according to any one of the above configurations [1] to [4],
[0096] wherein the plurality of strands (21) are made of aluminum or aluminum alloy.
[6] A terminal comprising:
[0097] a bottom portion (14) on which a conductor (23, 23A) having a plurality of strands (21) is set; and
[0098] a conductor caulking portion (16) and a connecting caulking portion (19) extended from the bottom portion (14) and respectively caulked in a manner to cover the conductor (23, 23A) so as to crimp the conductor (23, 23A),
[0099] wherein the conductor caulking portion (16) in which the conductor (23, 23A) is crimped, includes a stir welding area (A) into which a friction stir tool (51) is rotated and pressed and in which friction stir welding is performed.
DESCRIPTION OF REFERENCE NUMERALS AND SIGNS
[0100] 10: Terminal [0101] 14: Bottom portion [0102] 16: Conductor caulking portion [0103] 19: Connecting caulking portion [0104] 20, 20A: Electric wire [0105] 21: Elementary wire [0106] 23, 23A: Conductor [0107] 24: Insulating coating [0108] 35: Jig [0109] 36: Holding recessed portion [0110] 51: Friction stir tool [0111] A: Stir welding area