JP5041820B2 - Flat cable with terminal - Google Patents

Description

  The present invention relates to a flat cable with a terminal in which a piercing terminal is connected to a flat cable having a flat conductor.

  A wide variety of electronic devices are mounted on a vehicle as a moving body. In the automobile, a wire harness is routed to transmit electric power, a control signal, and the like to the electronic device. The wire harness has a plurality of electric wires and a plurality of connectors. The electric wire is a so-called covered electric wire having a conductive core wire and an insulator covering the core wire.

  The connector includes a pair of insulative connector housings that are fitted to each other and conductive terminal fittings that are accommodated in these housings. The terminal fitting has an electric wire connecting portion that is attached to one end of the electric wire and is electrically connected to the core wire, and an electric contact portion that contacts the mating terminal fitting on the other end. The wire harness transmits a control signal and the like to the electronic device by connector-connecting the connector housings.

  In recent years, the wiring amount of the wire harness described above tends to increase as the number of electronic devices mounted on the automobile increases. For this reason, FFC (Flexible Flat Cable), which is lighter and thinner than conventional round electric wires and enables high-density and space-saving wiring, is frequently used as the above-described electric wires. FFC is a flat electric wire in which flat conductors are arranged in parallel and covered with a synthetic resin or the like.

  As shown in FIG. 9, terminal fittings connected to the FFC include a rectangular tube-shaped electrical contact portion 121 and claw portions 124 erected from both edges of the bottom wall 123 connected to the electrical contact portion 121. A piercing terminal 102 having a wire connecting portion 122 having a.

  As shown in FIG. 10, the piercing terminal 102 is configured so that each claw portion 124 penetrates the insulator 132 and the conductor 131 of the FFC 103 and the claw portions 124 are bent inward from each other to grip the FFC 103. Close. The piercing terminal 102 is used in which the terminal width, that is, the width W1 between the outer surfaces of the claw portions 124 is narrower than the conductor width W2 of the FFC 103. The terminal-attached flat cable 101 to which the piercing terminals 102 are connected in this manner is housed in the connector housing and becomes the wire harness described above.

  By the way, with the above-described high-density mounting of automobile wiring components, the conductor width W2 (see FIG. 10) of the FFC 103 described above is becoming narrower. In the flat cable 101 with a terminal having the FFC 103 having a narrow conductor width W2, it is necessary to use the piercing terminal 102 having a narrow width W1 between the outer surfaces of the claw portions 124 corresponding to the FFC 103. However, in the piercing terminal 102 having the structure shown in FIGS. 9 and 10, the miniaturization has almost reached the limit in terms of strength and processing conditions. In other words, since the piercing terminal 102 that can be attached to the FFC 103 whose pitch is becoming narrower cannot be manufactured, further downsizing of automobile wiring parts such as connectors has been stopped. That is, a piercing terminal 102 having a narrower width W1 has been demanded.

Therefore, as a terminal connection structure to the FFC 103 having a narrow conductor width W2, a flat cable 201 with a terminal as shown in FIG. 11 (see Patent Document 1) has been proposed. The terminal fitting 202 shown in the figure has a rectangular tube-shaped electrical contact portion 221 and a bottom plate portion 223 that is continuous with the electrical contact portion 221 and on which the FFC 103 is overlaid. When connecting the terminal fitting 202 to the FFC 103, the FFC 103 is overlapped on the bottom plate portion 223, and two cuts A and A are made at the overlapping portions, and the portions on both sides orthogonal to the cuts A and A are placed. Make a difference. By doing so, as shown in FIG. 12, the conductor 131 of the FFC 103 exposed from the cuts A and A and the bottom plate portion 223 are brought into contact conduction.
JP 2004-39464 A

  However, the connection structure shown in FIGS. 11 and 12 has a problem that the connection reliability cannot be ensured because the FFC 103 and the terminal fitting 202 are not mechanically firmly connected. Furthermore, there is a problem that the exposed conductor 131 of the FFC 103 is exposed to the outside air and is oxidized to increase the electrical resistance value.

  Therefore, an object of the present invention is to provide a flat cable with a terminal that can be reduced in size and has excellent connection reliability.

In order to achieve the above object, the flat cable with a terminal according to claim 1 is capable of contacting a flat cable in which a flat conductor is covered with an insulator and the conductor through the flat cable. And a piercing terminal having at least a pair of claw portions spaced apart from each other, and a flat cable with a terminal, wherein a plurality of the claw portions are provided in a staggered manner, and the claw portions are opposed to each other. The allowable maximum value in consideration of the tolerance of the width Wz between the side surfaces is Wzmax, the allowable minimum value and the allowable maximum value in consideration of the tolerance of the width Wc of the conductor is Wcmin, Wcmax, and between the outer surfaces of the claw portions facing each other Wxmax ≦ Wcmin and Wcmax ≦ Wxmin (Wzmax <Wxmin) where Wxmin is an allowable minimum value in consideration of the tolerance of the width Wx of Plus, it is characterized in that the inner surface of at least one of the claw portions is in contact with the end face of the conductor.

In order to achieve the above-described object, the flat cable with a terminal according to claim 2 is capable of contacting a flat cable having a flat conductor covered with an insulator and the conductor penetrating the flat cable. And a piercing terminal having at least a pair of claw portions spaced apart from each other, and a flat cable with a terminal, wherein a plurality of the claw portions are provided in a staggered manner, and the claw portions are opposed to each other. The allowable maximum value in consideration of the tolerance of the width Wz between the side surfaces is Wzmax, the allowable minimum value and the allowable maximum value in consideration of the tolerance of the width Wc of the conductor is Wcmin, Wcmax, and between the outer surfaces of the claw portions facing each other Wxmax ≦ Wcmin and Wcmax ≦ Wxmin (Wzmax <Wxmin) where Wxmin is an allowable minimum value in consideration of the tolerance of the width Wx of Plus, it is characterized in that at least the inner surfaces of the pair of the claw portions are spaced from each other in contact with the end face of the conductor.

In the flat cable with a terminal according to claim 1 , the dimensions in consideration of the tolerance of the piercing terminal and the flat cable are formed so that the inner surface of the claw portion can come into contact with the end surface of the conductor. The width between the inner surfaces can be increased. Therefore, even a piercing terminal having the same dimensions as the conventional one can be attached to a flat cable having a narrower conductor width. Therefore, the size of the flat cable with terminals can be reduced. Further, since the inner surface of at least one row of the claw portions is in contact with the end surface of the conductor and the outer surface is not in contact with the conductor, no burr of the conductor is generated on the outer surface side when the claw portion penetrates the flat cable. Therefore, occurrence of a short circuit between terminals can be suppressed.

The flat cable with a terminal according to claim 2 has dimensions in consideration of tolerances of the piercing terminal and the flat cable, and is formed to have a dimension in which the inner side surface of the claw portion can come into contact with the end surface of the conductor. The width between the inner surfaces can be increased. Therefore, even a piercing terminal having the same dimensions as the conventional one can be attached to a flat cable having a narrower conductor width. Therefore, the size of the flat cable with terminals can be reduced. Further, since the inner side surfaces of the claw portions in both rows are in contact with the end face of the conductor and the outer side surface is not in contact with the conductor, no burr of the conductor is generated on the outer surface side when the claw portion penetrates the flat cable. Therefore, occurrence of a short circuit between terminals can be suppressed. Furthermore, even if the inner surface of the claw portion of one row of the piercing terminal is not in contact with the conductor due to an external load or the like, the claw portion of the other row is in contact with the conductor, ensuring electrical connection. can do.

  A flat cable with a terminal according to an embodiment of the present invention will be described below with reference to FIGS. In addition, the flat cable as used in this specification means the thing formed in flat strip | belt shape as a whole by covering a flat conductor with an insulator, such as FFC (Flexible Flat Cable).

  As shown in FIG. 1, the terminal-attached flat cable 1 includes an FFC 3 as a flat cable and a piercing terminal 2.

  The FFC 3 is a flat electric wire in which flat conductors 31 are arranged in parallel and both surfaces of the conductor 31 are covered with an insulator 32 such as polyester tape.

  As shown in FIGS. 1 and 2, the piercing terminal 2 is formed of conductive sheet metal or the like, and an electric contact portion 21 to which a mating terminal fitting is connected and an electric wire connection portion to which the FFC 3 is connected. 22. The electric wire connecting part 22 has a bottom wall 23 connected to the electric contact part 21 and a plurality of claw parts 24 which are provided upright from both edges of the bottom wall 23 and which are opposed to each other with a space therebetween. The plurality of claw portions 24 are arranged along the longitudinal direction of the piercing terminal 2, and the claw portions 24 that are opposed to each other with a space therebetween are arranged in a staggered manner. The claw portion 24 penetrates through the end portion of the FFC 3 and is electrically connected to the conductor 31. Thus, the piercing terminal 2 has at least one pair of claw portions 24 opposed to each other with a space therebetween.

Further, as shown in FIG. 3, the flat cable with terminal 1 is formed such that the width Wz between the inner side surfaces 25 of the claw portion 24 of the piercing terminal 2 is equal to or smaller than the width Wc of the conductor 31 of the FFC 3. Has been. Further, the width Wx between the outer surfaces 26 of the claw portion 24 is formed to be equal to or wider than the width Wc of the conductor 31. Further, the width Wx between the outer side surfaces 26 and 26 is necessarily wider than the width Wz between the inner side surfaces 25 and 25. When this is expressed by a formula, Formula 1 is obtained.
Wz ≦ Wc and Wc ≦ Wx (Wz <Wx) [Formula 1]

  In actual machining, it is impossible to finish the dimensions exactly the same as the reference dimensions determined at the time of design, resulting in unavoidable dimensional errors. For this reason, an allowable maximum value and an allowable minimum value allowed as actual dimensions are determined. The difference between the allowable maximum value and the allowable minimum value is called tolerance. That is, if the actual dimension of a certain product is within the tolerance, it is determined that the product is acceptable.

Here, the width Wz between the inner side surfaces 25, 25 of the claw part 24, the width Wc of the conductor 31 of the FFC 3, and the width Wx between the outer side surfaces 26, 26 of the claw part 24 are expressed by equations taking the above tolerance into consideration. Equations 2 to 4 are obtained.
Wzmin (allowable minimum value) ≦ Wz ≦ Wzmax (allowable maximum value) [Formula 2]
Wcmin (allowable minimum value) ≦ Wc ≦ Wcmax (allowable maximum value) [Formula 3]
Wxmin (allowable minimum value) ≦ Wx ≦ Wxmax (allowable maximum value) [Formula 4]

Then, when Expressions 2 to 4 are substituted into Expression 1, Expression 5 is obtained.
Wzmin ≦ Wz ≦ Wzmax ≦ Wcmin ≦ Wc ≦ Wcmax and Wcmin ≦ Wc ≦ Wcmax ≦ Wxmin ≦ Wx ≦ Wxmax (Wzmax <Wxmin) [Formula 5]

Here, focusing on the mutual magnitude relationship among the width Wz, the width Wc, and the width Wx, formula 6 can be summarized as formula 6.
Wzmax ≦ Wcmin and Wcmax ≦ Wxmin (Wzmax <Wxmin) [Formula 6]

  As shown in FIG. 4, the flat cable 1 with terminals satisfying the above formulas 1 to 6 includes a pair of claw portions 24 of the piercing terminals 2 that face each other with a space therebetween, and pass through the insulator 32 of the FFC 3. Both inner side surfaces 25 of the pair of claw portions 24 come into contact with the end surfaces of the conductors 31 so that they are electrically connected. And the claw part 24 which penetrated FFC3 is crimped | curved so that the front-end | tip may be bent mutually inward and grip FFC3.

  According to the flat cable 1 with a terminal of this embodiment, since the width of the piercing terminal 2, that is, the width between the inner surfaces 25 of the claw portion 24 can be increased, the piercing terminal 2 having the same dimensions as the conventional one can be obtained. However, it can be attached to the FFC 3 having a narrower conductor 31 width. Therefore, size reduction of the flat cable 1 with a terminal can be achieved.

  Moreover, according to the flat cable 1 with a terminal of this embodiment, since the inner surface 25 of the nail | claw part 24 contacts the end surface of the conductor 31, and the outer surface 26 does not contact the conductor 31, the nail | claw part 24 penetrates FFC3. At this time, no burrs of the conductor 31 occur on the outer surface 26 side. Therefore, occurrence of a short circuit between terminals can be suppressed.

  Furthermore, according to the flat cable 1 with a terminal of this embodiment, even when the inner surface 25 of the claw part 24 of one row of the piercing terminal 2 is not in contact with the conductor 31 due to an external load or the like, the other row Since the nail | claw part 24 is contacting the conductor 31, it can ensure electrical connection.

  Next, the inventors set the FFC having a conductor thickness of 0.2 mm and a conductor width (Wc) of 1.57 mm, a plate thickness of 0.2 mm, a width between outer surfaces (Wx) of 1.00 mm, and a width between inner surfaces. (Wz) A conventional product 1 obtained by attaching a piercing terminal of 0.60 mm, an FFC with a conductor thickness of 0.2 mm and a conductor width (Wc) of 1.57 mm, a plate thickness of 0.2 mm, and a width between outer surfaces ( The effect of the present invention was confirmed by photographing a cross section of the product 1 of the present invention obtained by attaching a piercing terminal having a width (Wx) of 1.70 mm and a width between inner surfaces (Wz) of 1.30 mm. A cross-sectional photograph of the conventional product 1 is shown in FIG. 5, and a cross-sectional photograph of the product 1 of the present invention is shown in FIG. 7 is a schematic diagram of FIG. 5, and FIG. 8 is a schematic diagram of FIG.

  As shown in FIG. 5 to FIG. 8, the conventional product 1 in which the claw portion penetrates the FFC conductor, the claw portion penetrates the FFC insulator, and the inner surface of the claw portion contacts the end face of the FFC conductor. In both cases, the outer surface of the claw portion is not in contact with the FFC conductor or insulator, and only the inner surface of the claw portion is in contact with the FFC conductor. From this, it can be proved that the product 1 of the present invention has the same reliability as the comparative example 1.

  In the above-described embodiment, the flat cable with terminal 1 has the FFC 3 as a flat cable. However, the flat cable with terminal of the present invention may not necessarily have the FFC, and instead of the FFC, the FPC may be used. You may have.

  In the above-described embodiment, the electrical contact portion 21 of the piercing terminal 2 is a hollow rectangular tube-shaped female contact portion. However, in the present invention, even if the electrical contact portion 21 is a rod-shaped male contact portion. Of course it is good.

  Furthermore, in the above-described embodiment, the inner side surfaces 25 of the pair of claw portions 24 facing each other with a space between the piercing terminals 2 are in contact with the end surfaces of the conductors 31, but in the flat cable with terminals of the present invention, The inner surface 25 of the at least one claw portion 24 only needs to be in contact with the end surface of the conductor 31.

  In addition, embodiment mentioned above only showed the typical form of this invention, and this invention is not limited to embodiment. That is, various modifications can be made without departing from the scope of the present invention.

It is a perspective view which shows the flat cable with a terminal concerning one embodiment of this invention. It is a disassembled perspective view of the flat cable with a terminal shown in FIG. It is a figure explaining the dimensional relationship of the flat cable with a terminal shown in FIG. It is sectional drawing along the BB line in FIG. It is a cross-sectional photograph of the conventional flat cable with a terminal. It is a cross-sectional photograph of the flat cable with a terminal of this invention. It is a schematic diagram of the cross-sectional photograph shown by FIG. It is a schematic diagram of the cross-sectional photograph shown by FIG. It is a perspective view which shows the conventional piercing terminal. It is sectional drawing of the conventional flat cable with a terminal. It is a perspective view of the flat cable with a terminal shown by patent document 1. FIG. It is sectional drawing along the EE line in FIG.

Explanation of symbols

1 Flat cable with terminal 2 Piercing terminal (terminal fitting)
23 bottom wall 24 claw part 25 inner side 26 outer side 3 FFC (flat cable)
31 Conductor 32 Insulator

Claims (2)

A flat cable in which a flat conductor is covered with an insulator, and a piercing terminal that has at least a pair of claws that can pass through the flat cable and come into contact with the conductor and are spaced apart from each other. A flat cable with terminals,
A plurality of the claw portions are provided in a zigzag shape,
Wzmax is an allowable maximum value considering the tolerance of the width Wz between the inner side surfaces of the claw portions opposed to each other, and Wcmin and Wcmax are allowable minimum values and allowable maximum values considering the tolerance of the width Wc of the conductor. When the allowable minimum value considering the tolerance of the width Wx between the outer surfaces of the claw parts is Wxmin,
Wzmax ≦ Wcmin and Wcmax ≦ Wxmin (Wzmax <Wxmin) are satisfied,
An inner surface of at least one of the claw portions is in contact with an end surface of the conductor. A flat cable in which a flat conductor is covered with an insulator, and a piercing terminal that has at least a pair of claws that can pass through the flat cable and come into contact with the conductor and are spaced apart from each other. A flat cable with terminals,
A plurality of the claw portions are provided in a zigzag shape,
Wzmax is an allowable maximum value considering the tolerance of the width Wz between the inner side surfaces of the claw portions opposed to each other, and Wcmin and Wcmax are allowable minimum values and allowable maximum values considering the tolerance of the width Wc of the conductor. When the allowable minimum value considering the tolerance of the width Wx between the outer surfaces of the claw parts is Wxmin,
Wzmax ≦ Wcmin and Wcmax ≦ Wxmin (Wzmax <Wxmin) are satisfied,
An inner surface of at least a pair of the claw portions spaced from each other is in contact with an end surface of the conductor.