JP2012064520A - Method of crimping terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid that, even when a size restriction or the like is imposed on a terminal forming piece for crimping a signal conductor to be cut, a core wire of the signal conductor is held between both end portions (individual end portions), and protrudes from between the both end portions when crimping the terminal forming piece onto the signal conductor.SOLUTION: Opposing both end portions of a terminal forming piece body 12a are subjected to drawing processing, thereby forming extension parts E that become thinner than the terminal forming piece body 12a. The terminal forming piece body 12a is mounted on a lower die 19, and an upper die 18 is lowered with respect to the lower die 19. The terminal forming piece body 12a is bent so that the extension parts E approach each other and the signal conductor 14 is enclosed inside the extension parts E and the terminal forming piece body 12a, and the extension parts E are crushed so as to deform the shape of the extension parts E.

Description

  The present invention relates to a terminal crimping method in which a terminal is crimped to a signal conductor of an electric wire using a mold.

  As a conventional shield wire terminal connection structure, the shield conductor is covered around the signal conductor connected to the inner conductor terminal via an insulating inner sheath, and the outer periphery of the shield conductor is covered with an insulating outer sheath. And what connected the outer conductor terminal to the terminal part of the said shield conductor is disclosed by patent document 1. FIG.

  This shielded wire terminal connection structure has a wire barrel composed of a pair of crimping pieces for sandwiching the shielded wire (conductor) exposed from the shielded wire terminal to an outer conductor terminal. The crimping process of the shielded wire with the crimped piece of the wire barrel is as follows.

  First, as shown in FIG. 5A, a crimper 40 is disposed above the wire barrel 26 and the shielded electric wire 10 placed thereon, and an anvil 42 is disposed below the wire barrel 26. At the time of the crimping process, the wire barrel crimper 40 descends from above the wire barrel 26 and the shielded electric wire 10 placed thereon, and first, on the mold inner wall surface 76 of the shallower recess of the crimper 40 in the figure. The left pressure contact piece 30b comes into contact and begins to bend inward along the inner wall surface 76 of the mold. Further, the crimper 40 continues to descend, and the crimping piece 30a on the right side comes into contact with the deeper inner wall 80 of the crimper 40, and the crimping piece 30a is also along the inner mold wall 80 with the left crimping piece 30b. Begin to bend inward.

  Further, the anvil 42 disposed under the wire barrel 26 sandwiches the wire barrel 26 and the shielded electric wire 10 placed thereon with the crimper 40. Then, as shown in FIG. 5B, the tips of the crimping pieces 30 a and 30 b reach the projecting portion 78 near the center axis of the crimper 40, and wrap the shielded electric wire 10.

  As shown in FIG. 5 (c), the tip of the left crimping piece 30 b that has begun to be bent first on the wire barrel 26 side is guided by a projecting portion 78 near the center of the crimper 40 and guided downward. Further, the tip of the right crimping piece 30a, which has started to bend later, bends so as to overlap the left crimping piece 30b. Further, the crimper 40 continues to descend, and the bending progresses without the tips of the crimping pieces 30a and 30b reaching the projecting portion 78 near the center of each crimper 40 colliding.

  Here, on the wire barrel 26 side, the crimping piece 30b bent along the shallower mold inner wall surface 76 of the crimper 40 wraps around the opposite crimping piece 30a, and FIG. 5 (c) and FIG. As shown in FIG. 5 (d), the tip of the crimping piece 30a on the right side in the drawing is sandwiched and pressed between the tip of the crimping piece 30b bent from the left side and the protruding portion 78 of the crimper 40. At this time, the tip of the crimping piece 30a is pushed in the direction indicated by the arrow 62 in FIG.

  The crimper 40 continues to descend further, and as shown in FIG. 5 (d), on the wire barrel 26 side, the tip of the left crimping piece 30b is below the right crimping piece 30a and the tip of the right crimping piece 30a is The upper side of the left crimping piece 30b is overlapped and overlapped evenly from both the left and right sides, and finally, as shown in FIG. Thus, it is possible to obtain a terminal connection structure of a shielded wire in a good crimped state without any deviation.

JP 2006-147223 A

The above-described conventional shield wire terminal connection structure has the following problems to be solved.
That is, the shielded electric wire 10 is not in the normal caulking position of the wire barrel 26 but is lifted from the bottom (concave portion) of the wire barrel 26 due to vibrations generated when the crimper 40 is lowered as shown in FIG. As a result, a gap H as shown in FIG. In this case, when the tips of the crimping pieces 30a and 30b of the wire barrel 26 start to interfere (contact) with the inner wall surfaces 76 and 80 of the mold as shown in FIG. ) Cannot be brought into contact with the shielded electric wire 10. For this reason, the wire barrel 26 is bent so as to be freely bent around the central portion which is the bottom thereof, and the curvature of the bent portion becomes extremely small. Accordingly, if the crimper 40 continues to descend in this state as described above, when the crimping pieces 30a and 30b wrap the shielded electric wire 10 while keeping the gap H, a part (upper part) of the shielded electric wire 10 is illustrated. As shown to 6 (b), it will be inserted | pinched in the state which protruded between each crimping | compression-bonding pieces 30a and 30b. As a result, there is an inconvenience that the shielded electric wire 10 is not completely held by the wire barrel 26 and the shielded electric wire 10 comes out of the wire barrel 26.

  Furthermore, the same problem as described above also occurs between a signal conductor composed of a plurality of core wires and a terminal held by crimping on the signal conductor. For example, as shown in FIG. 7A, when the terminal forming piece 54 bent into a U-shape constituting the terminal 53 is pressed and held on the signal conductor 52 formed of the seven core wires 51, the upper die 55. The plurality of core wires 51 constituting the signal conductor 52 are separated by receiving the vibration when the lower die 56 is lowered. At this time, the lowermost one core wire 51 is positioned on the upper surface (bottom surface) of the central portion of the U-shaped terminal forming piece 54, and the other six core wires 51 are placed on the core wire 51. When the terminal forming piece 54 is bent inward along the inner mold wall surface 57 of the upper mold 55, the central portion (bottom) of the terminal forming piece 54 changes narrowly. For this reason, the other six core wires 51 are pushed upward relatively, and each end portion (both end portions) in the width direction of the terminal forming piece 54 encloses each core wire 51 as the upper die 55 continues to descend. As shown in FIG. 7B, the core wire 51 located at the top may be sandwiched between the end portions or may protrude from the end portions to the outside. This phenomenon occurs when the length of the terminal forming piece 54 is insufficient. For this reason, what is necessary is just to take the press cutting length from the carrier of the terminal formation piece 54 sufficiently large. However, the required press cutting length may not be obtained due to restrictions such as the size of the carrier and the number of collected terminal forming pieces 54.

  The present invention has been made in view of the above-described circumstances, and the purpose thereof is the size of the terminal forming piece for signal conductor crimping that is press-cut from the carrier or the like, the size of the carrier, the number of collected terminal forming pieces, and the like. Even when there are restrictions, the core wire that constitutes the signal conductor is sandwiched between both ends (between each end) of the terminal forming piece when crimping (clamping) to the signal conductor, or between both ends It is an object of the present invention to provide a method for crimping a terminal so that the terminal does not protrude outside.

In order to achieve the above-described object, the terminal crimping method according to the present invention is characterized by the following (1).
(1) The terminal forming piece of a terminal including a carrier and flat terminal forming pieces provided continuously at a plurality of positions in the longitudinal direction of the carrier is crimped to a signal conductor exposed at a part of the electric wire. A terminal crimping method for
Stretching both opposite ends of the terminal forming piece body to form an extending portion that is thinner than the terminal forming piece body,
Place the terminal forming piece body on the lower mold,
The upper mold is lowered with respect to the lower mold, and the terminal forming piece main body is bent so that the extending portions approach each other and the signal conductor is enclosed inside the extending portion and the terminal forming piece main body. And crushing the stretched parts together so as to deform the shape of the stretched parts,
thing.

  According to the terminal crimping method of (1) above, the end forming part of the terminal forming piece is stretched so that it is thinner than the thickness of other parts, and this is used as the stretched part. Thus, the width between the end portions of the terminal forming piece can be substantially extended, so that when the signal conductor arranged on the terminal forming piece is crimped so as to be wrapped at both end portions of the terminal forming piece, both ends thereof The signal conductor can be wrapped with a margin by the both end portions having the extending portion so as not to protrude from between the portions. This ensures the mechanical and electrical connection between the signal conductor and the terminal forming piece.

  According to the present invention, when the terminal forming piece is crimped to the signal conductor of the electric wire, the signal conductor placed on the terminal forming piece is more securely surrounded by the extending portions extending to both ends of the terminal forming piece. be able to. As a result, it is possible to prevent the core wire of the signal conductor from being sandwiched between the both end portions or protruding from between the both end portions. As a result, the mechanical and electrical coupling between the signal conductor and the terminal forming piece can be reliably and stably maintained.

  The present invention has been briefly described above. Further, details of the present invention will be further clarified by reading through the modes for carrying out the invention described below with reference to the accompanying drawings.

It is a perspective view which shows the manufacturing process of the chain terminal concerning embodiment of this invention. It is sectional drawing of the terminal formation piece shown in FIG. It is an expanded sectional view of the extending | stretching part of the terminal formation piece shown in FIG. FIG. 4 is an explanatory view showing a caulking process for caulking an electric wire with a terminal forming piece in FIG. 3, and FIGS. 4 (a) to 4 (d) are cross-sectional views showing a point in time of the caulking process. It is explanatory drawing which shows the crimping | compression-bonding process by the wire barrel of the conventional shielded electric wire, Comprising: Fig.5 (a)-FIG.5 (e) are sectional drawings which respectively show the one point of the crimping process. It is explanatory drawing which shows the inappropriate crimping deformation | transformation process by the wire barrel of the conventional shielded electric wire, Comprising: Fig.6 (a)-FIG.6 (b) are sectional drawings which respectively show the one point of the crimping deformation process. It is explanatory drawing which shows the inappropriate crimping deformation process by the terminal formation piece of the conventional signal conductor, Comprising: Fig.7 (a)-FIG.7 (b) are sectional drawings which respectively show the one point of the crimping deformation process. .

  A terminal crimping method according to an embodiment of the present invention will be described below with reference to FIGS.

  The chain terminal shown in FIG. 1 has a carrier 11 and flat terminal-forming pieces 12 provided continuously at a plurality of locations in the longitudinal direction of the carrier 11. The terminal forming piece 12 is formed as a terminal by press molding, and the tip end portion of the signal conductor 14 of the electric wire 13 is accommodated in the terminal forming piece 12 bent at the time of the press forming. Further, the terminal forming pieces 12 are continuously provided at a plurality of locations in the longitudinal direction of the carrier 11 through carrier tabs 15.

  The signal conductor 14 is formed by bundling a plurality of core wires 14a. The front end of the signal conductor 14 is placed at the center of the terminal forming piece 12, and the left and right ends of the terminal forming piece 12, that is, the ends facing each other in parallel are the signal conductor 14 of the electric wire 13. The terminal forming piece 12 is crimped and crimped to the signal conductor 14 by being bent toward the direction.

  In this case, the terminal forming piece 12 is press-cut from the carrier 11 so as to have a width dimension that matches the outer diameter size of the signal conductor 14 crimped by the terminal forming piece 12. For this reason, when the outer diameter of the signal conductor 14 to be crimped is large, it is necessary to increase the width of the terminal forming piece 12 to be crimped, the size of the carrier, the number of collected terminal forming pieces 54, etc. It is impossible to press-cut to a width larger than necessary due to restrictions of the above.

  On the other hand, when the signal conductor 14 is placed on the terminal forming piece 12 and the terminal forming piece 12 is bent and bent so as to wrap the signal conductor 14, the core wire 14a constituting the signal conductor 14 is separated. In this case, since the width of the terminal forming piece 12 cannot be increased due to restrictions such as the size of the carrier and the number of collected terminal forming pieces, the uppermost core wire on the terminal forming piece 12 is between the both ends of the terminal forming piece 12. There is a risk of being pinched or protruding from between both ends.

  In the present embodiment, before crimping the terminal forming piece 12, both end portions of the terminal forming piece 12 formed by press cutting in the longitudinal direction of the carrier 11, that is, end portions facing each other in parallel in the terminal forming piece 12 are formed. The film is stretched so that it is thinner than other parts. 2 and 3 show the stretched portion E that has been stretched. By this stretching process, the length L (stretched portion) is longer than both end surfaces of the terminal forming piece 12 (surface T intersecting substantially at right angles to the surface R and the back surface S of the terminal forming piece 12) as compared to before stretching. Only stretch. That is, the width dimension of the terminal forming piece 12 is extended.

  In addition, although the thing of the form which cut | disconnected the both ends of the terminal formation piece 12 diagonally on the surface R side was shown as the said extending | stretching part E, it is a knife edge shape on both sides of the surface R and the back surface S of the both ends. It can be made into various taper stretched forms, such as the form which carried out the diagonal cut.

  Next, a process of crimping the signal conductor 14 into the terminal forming piece main body 12a of the terminal forming piece 12 by press molding without causing protrusion of the core wire 14a using FIGS. 4 (a) to 4 (d). explain. 4 (a) to 4 (c) show the terminal-forming piece main body 12a by the upper die 18 and the lower die 19 that supports the terminal-forming piece 12 press-molded into a C shape as shown in FIG. A caulking process is shown. The upper mold 18 has a pair of mold inner wall surfaces 18a that expands in a substantially V shape downward on its lower surface. The depth and width of the V-shaped portion forming these mold inner wall surfaces 18a are set in advance according to the size of the terminal forming piece body 12a to be crimped, the cross-sectional area of the signal conductor 14, and the like. Further, a circular arc surface 17 is formed at a location where these inner wall surfaces 18a intersect, that is, near the bottom of the V-shaped portion.

  On the other hand, the lower mold 19 has an arc-shaped mold inner wall surface 19a on the surface side (upper surface side) facing the mold inner wall surfaces 18a, 18a of the upper mold 18. The mold inner wall surface 19a is also sized and shaped so that the terminal forming piece 12 on which the signal conductor 14 is placed can be caulked and fixed to the signal conductor 14 together with the mold inner wall surface 18a. Therefore, when the signal conductor 14 exposed from the electric wire 13 is placed on the C-shaped portion of the terminal forming piece main body 12a, and the terminal forming piece main body 12a is closed and crimped to the signal conductor 14, the lower mold 19 The bottom of the C-shaped terminal forming piece main body 12a is placed on the arc-shaped inner wall surface 19a.

  Here, the upper die 18 is lowered (dropped), and both end portions of the terminal forming piece main body 12 a are brought into contact with the inner wall surface 18 a of the V-shaped portion of the upper die 18. When the upper die 18 is further lowered, both end portions of the upper die 18 begin to bend along the inner wall surface 18a of the die by an equal amount and bend toward the signal conductor 14. Thus, the signal conductor 14 is encased in the terminal forming piece main body 12a, and the extending portions E extended at both ends of the terminal forming piece main body 12a approach each other while facing each other. The core wire 14a is gradually pushed up in the arrow direction (upward direction) of FIG.

  When the core wires 14a are pushed up, the uppermost core wire 14a is likely to protrude from both ends of the terminal forming piece main body 12a. However, since the extending portions E made by crushing molding as described above are extended at both ends of the terminal forming piece main body 12a, the entire width of the terminal forming piece main body 12a is expanded. Yes. Therefore, in the process of bending both end portions along the inner wall surfaces 18a, as shown in FIG. 4 (c), the extending portion E covers the uppermost core wire 14a with a margin. Can be bent. For this reason, the uppermost core wire 14a does not stick out from between the stretched portions E to be joined to each other, and the stretched portions E facing each other overlap or abut each other and further crush each other As shown in FIG. 4D, the terminal forming piece main body 12a is deformed into an arc shape and is formed into a cylindrical shape.

  Therefore, the terminal forming piece 12 with the signal conductor 14 crimped as described above is separated from the lower mold 19 by raising the upper mold 18. Thus, the signal conductor 14 and the terminal forming piece 12 formed by the upper mold 18 and the lower mold 19 have a circular cross-sectional shape as shown in FIG. 1 and FIG. At the same time, a terminal is formed in close contact therewith. In addition, since the terminal obtained in this way does not protrude from the terminal forming piece 12 of the electric wire 13 during the caulking process as described above, the expected mechanical strength and electrical connection can be realized. Become.

  In the present embodiment, the case where the core wire 14a of the signal conductor 14 is prevented from protruding from between the end portions of the terminal forming piece main body 12a during the caulking process has been described. This crimping method (crimping method) is also applied to prevent a part of the shield wire from protruding between the ends of the terminal forming piece when fixing by crimping the terminal forming piece such as it can.

  Further, in the present embodiment, the terminal crimping method has been described in the case where it is used for manufacturing a chain terminal constituted by a plurality of terminal forming pieces connected to a carrier. However, other common signal conductor core wires are used. The terminal crimping method of the present embodiment can be employed for crimping the terminal with respect to.

  As described above, the terminal crimping method of the present embodiment is stretched by the upper mold 18 of the molds to be crimped so that the thicknesses of the end portions facing each other in advance are thinner than those of other portions. The terminal forming piece 12 that has been processed and placed on the lower die 19 of the mold is moved so that both end portions of the terminal forming piece 12 approach each other by a mold inner wall surface 18a formed on the lower surface of the upper die 18. In addition, the both ends of the terminal forming piece 12 are crushed together while being bent so that the signal conductors 14 are enclosed inside the terminal forming pieces 12.

  Thereby, since the entire width of the terminal forming piece is substantially expanded by the extending portion thinned by the extending process, the signal conductor disposed on the terminal forming piece includes both ends including the extending portion of the terminal forming piece. Therefore, it is possible to reliably prevent the core wire of the signal conductor from protruding from between both ends thereof. As a result, the mechanical and electrical coupling between the signal conductor and the terminal forming piece is ensured.

DESCRIPTION OF SYMBOLS 10 Shield electric wire 11 Carrier 12 Terminal formation piece 12a Terminal formation piece main body 13 Electric wire 14 Signal conductor 15 Carrier clip 17 Arc surface 18 Upper mold | type 18a Type | mold inner wall surface 19 Lower mold | type 19a Type | mold inner wall surface 26 Wire barrel 30a, 30b Crimp piece 40 Anvil 51 Core wire 52 Signal conductor 53 Terminal 54 Terminal forming piece 55 Upper die 56 Lower die 57 Inner wall surface 76 Inner wall surface 78 Projection portion 80 Inner wall surface R Surface S Back surface T End surface

Claims (1)

A terminal for crimping the terminal forming piece of the terminal comprising a carrier and flat terminal forming pieces provided continuously at a plurality of locations in the longitudinal direction of the carrier to a signal conductor exposed in a part of the electric wire The crimping method of
Stretching both opposite ends of the terminal forming piece body to form an extending portion that is thinner than the terminal forming piece body,
Place the terminal forming piece body on the lower mold,
The upper mold is lowered with respect to the lower mold, and the terminal forming piece main body is bent so that the extending portions approach each other and the signal conductor is enclosed inside the extending portion and the terminal forming piece main body. And crushing the stretched parts together so as to deform the shape of the stretched parts,
A terminal crimping method characterized by the above.

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