JP7091665B2 - Cable terminal structure and its manufacturing method - Google Patents

Description

The present invention relates to a cable terminal structure having an insulated wire and a sheath provided around the insulated wire.

Today, various cables such as electric power cables and communication cables are used in various fields. One of these cables is a cable having an insulated wire as a core wire and a sheath provided around the insulated wire. This type of cable is used, for example, in an in-vehicle sensor such as an ABS sensor, a torque sensor, and an index sensor. Further, the insulated wire used as the core wire of this type of cable has a conductor and an insulating layer provided around the conductor. Hereinafter, unless otherwise specified, the "cable" shall mean a cable having an insulated wire as a core wire and a sheath provided around the insulated wire.

As the terminal structure of the cable, a structure is known in which the end portion of the sheath and the root portion of the insulated wire protruding from the end portion of the sheath are collectively covered with a resin. In other words, a cable provided with a resin molded body at one end or both ends of the cable that collectively covers the end of the sheath and the root of the insulated wire protruding from the end of the sheath (“cable with resin molded body”). Is sometimes called.) Is known. Such a cable terminal structure is mainly intended to ensure waterproofness at the end of the cable.

Japanese Unexamined Patent Publication No. 2007-95439

The cable terminal structure as described above is manufactured by supplying a molten resin material into a mold in which a cable end is arranged to form the resin molded body. At this time, the surface layer portion of the sheath or the insulated wire is melted by the heat of the resin material supplied into the mold, and the surface layer portion of the sheath or the insulated wire is bonded to the resin molded body. As a result, the waterproofness of the cable end is ensured.

Here, urethane is often used as the material for the insulating layer of the sheath and the insulated electric wire. On the other hand, nylon is often used as the material of the resin molded body constituting the cable terminal structure, and in particular, polyamide (PA (polyamide)) is often used. However, from the viewpoint of increasing the strength and durability of the resin molded product, the resin molded product is molded from nylon other than polyamide, for example, polyphthalamide (PPA) or polyphenylene sulfide (PPS). May be preferable.

However, while the melting point of PA is about 220 ° C, the melting point of PPA is about 320 ° C and the melting point of PPS is about 290 ° C. Therefore, when a resin molded body is molded using PPA or PPS, the insulating layer of the sheath or the insulated wire may be damaged by heat, and sufficient waterproofness may not be obtained. This problem is not limited to the case of molding the resin molded body constituting the cable terminal structure using PPA or PPS, but also the case of molding the resin molded body using another resin material having a melting point higher than that of PA. Is also a problem that can occur.

An object of the present invention is to provide a cable terminal structure and a method for manufacturing the same, which can reduce damage to the cable due to heat of the resin material when the end of the cable is resin-molded.

The cable terminal structure of the present invention is a cable terminal structure having an insulated wire and a sheath provided around the insulated wire. This cable terminal structure is provided in a holder accommodating an end portion of the sheath and a root portion of the insulated wire protruding from the end surface of the sheath, and is provided on the outside of the holder, and is provided from at least a part of the holder and the holder. It has an outer resin molded body that covers a part of the protruding sheath, and an inner resin molded body that is provided inside the holder and covers the root portion of the insulated wire. Then, the outer resin molded body and the inner resin molded body are connected and integrated through an opening provided in the holder.

The method for manufacturing a cable terminal structure of the present invention is a method for manufacturing a cable terminal structure having an insulated wire and a sheath provided around the insulated wire. In this manufacturing method, the end portion of the sheath and the root portion of the insulated wire protruding from the end surface of the sheath are housed in the holder, and at least a part of the holder and the protrusion from the holder are projected outside the holder. An outer resin molded body that covers a part of the sheath is molded, and an inner resin molded body that covers the root portion of the insulated wire is molded inside the holder.

According to the present invention, there is realized a cable terminal structure and a method for manufacturing the same, which can reduce damage to the cable due to the heat of the resin material when the end of the cable is resin-molded.

It is a figure which shows the structure of a cable. It is a figure which shows the holder and the end of a cable accommodated in the holder. It is a figure which shows the structure of a holder. It is a figure which shows the wall part provided in the holder. It is a figure which shows the cable terminal structure. It is a figure which shows one process of the manufacturing method of a cable terminal structure.

Next, an example of the embodiment of the cable terminal structure of the present invention will be described in detail with reference to the drawings. The cable terminal structure described here is a cable terminal structure having an insulated wire and a sheath provided around the insulated wire. Therefore, after explaining the structure of the cable, the terminal structure of the cable will be described in detail.

The cable 1 shown in FIG. 1 has a pair of insulated wires 3 and 4 and a sheath 5 that collectively covers the insulated wires 3 and 4. In other words, the cable 1 is a two-core cable having a pair of insulated wires 3 and 4 as core wires.

Each of the insulated wires 3 and 4 has a conductor 6 and an insulating layer 7 provided around the conductor 6. The conductor 6 is a stranded wire in which a plurality of strands are collectively twisted, and the insulating layer 7 is formed of urethane. The type of the wire forming the conductor 6 is not particularly limited, and for example, an annealed copper wire, a hard copper wire, a tin-plated annealed copper wire, a tin-plated hard copper wire, or the like can be used. The method of twisting the strands is not limited to collective twisting, and may be, for example, concentric twisting or composite twisting. Further, the insulating layer 7 may be formed of a resin material other than urethane.

The sheath 5 is made of urethane and collectively covers the insulated wires 3 and 4 arranged in parallel with each other. The sheath 5 maintains the distance between the pair of insulated wires 3 and 4. However, the sheath 5 may be formed of a resin material other than urethane.

As shown in FIG. 1, the insulated wires 3 and 4 are exposed at at least one end of the cable 1. Specifically, the insulated wires 3 and 4 project from at least one end 5a of the sheath 5. More specifically, the insulated wires 3 and 4 project from at least one end surface 5b of the sheath 5.

As shown in FIGS. 2 and 3, the end of the cable 1 is housed in the holder 10. Specifically, the end portion 5a of the sheath 5 and a part (root portions 3a, 4a) of the insulated wires 3 and 4 protruding from the end portion 5a are housed in the holder 10. In the following description, the end portion 5a of the sheath 5 and the root portions 3a, 4a of the insulated wires 3 and 4 housed in the holder 10 may be collectively referred to as "cable end portions". In other words, the portion of the cable 1 in which the holder 10 is housed is the "cable end". Further, among the exposed portions of the insulated wires 3 and 4 protruding from the end portion 5a of the sheath 5, the portions housed in the holder 10 are the root portions 3a and 4a.

As shown in FIGS. 2 and 3, the holder 10 is formed by a lower holder member 11 and an upper holder member 12 which are butted against each other from both sides in the radial direction of the cable 1. When the lower holder member 11 and the upper holder member 12 are abutted against each other, the sheath accommodating portion 13 in which the end portion 5a of the sheath 5 is accommodated and the root portion of the insulated wires 3 and 4 are accommodated between the both members 11 and 12. An electric wire accommodating portion 14 accommodating 3a and 4a is formed. That is, the sheath accommodating portion 13 and the electric wire accommodating portion 14 are provided inside the holder 10, the end portion 5a of the sheath 5 is accommodated in the sheath accommodating portion 13, and the roots of the insulated wires 3 and 4 are accommodated in the electric wire accommodating portion 14. Parts 3a and 4a are housed.

Further, a wall portion 20 that separates the sheath accommodating portion 13 and the electric wire accommodating portion 14 is provided inside the holder 10, and the root portions 3a and 4a of the insulated electric wires 3 and 4 are respectively provided in the wall portion 20. A through hole 21 is formed. The wall portion 20 is formed of a lower side wall portion 22 integrally molded with the lower holder member 11 and an upper side wall portion 23 integrally molded with the upper holder member 12.

When the lower holder member 11 and the upper holder member 12 are abutted against each other, the end surface of the lower side wall portion 22 and the end surface of the upper side wall portion 23 are abutted at the same time, and the wall portion 20 is formed inside the holder 10. Further, on the end faces of the lower side wall portion 22 and the upper side wall portion 23, two semi-circular recesses 24 for receiving the root portions 3a and 4a of the insulated wires 3 and 4 are formed, and the corresponding recesses 24 are connected to each other. The holes 21 are formed by being butted. As a result, the root portions 3a and 4a of the insulated wires 3 and 4 protruding from the end surface 5b of the sheath 5 housed in the sheath accommodating portion 13 penetrate the wall portion 20 and enter the electric wire accommodating portion 14. .. On the other hand, as shown in FIG. 4, the end surface 5b of the sheath 5 is covered with the wall portion 20 and is not exposed to the electric wire accommodating portion 14 (FIGS. 2 and 3).

As shown in FIG. 2, inside the holder 10 (inside the wire accommodating portion 14), an inner resin molded body 30 that covers the root portions 3a, 4a of the insulated wires 3 and 4 is provided. In other words, the root portions 3a and 4a of the insulated wires 3 and 4 are resin-molded in the electric wire accommodating portion 14. Further, as shown in FIG. 5, an outer resin molded body 31 is provided on the outside of the holder 10 to cover at least a part of the holder 10 and a part of the sheath 5 protruding rearward from the holder 10. In other words, a part of the holder 10 and a part of the sheath 5 protruding from the holder 10 are resin-molded. The waterproofness of the cable end is ensured by the molding by the inner resin molded body 30 and the outer resin molded body 31. The tips of the insulated wires 3 and 4 protruding from the front surface of the holder 10 are connected to an IC or other electronic device.

Although the details will be described later, the inner resin molded body 30 shown in FIG. 2 and the outer resin molded body 31 shown in FIG. 5 are simultaneously molded by the same resin material. Further, the inner resin molded body 30 and the outer resin molded body 31 are connected and integrated through an opening provided in the holder 10. The inner resin molded body 30 and the outer resin molded body 31 in the present embodiment are formed of polyphthalamide (PPA) or polyphenylene sulfide (PPS). Further, the inner resin molded body 30 and the outer resin molded body 31 in the present embodiment are connected and integrated through a through hole 15 (FIGS. 2 and 3) as an opening provided in the lower holder member 11. ing.

Here, as described above, the end surface 5b of the sheath 5 is covered with the wall portion 20 that separates the sheath accommodating portion 13 and the electric wire accommodating portion 14. That is, the wall portion 20 is interposed between the end surface 5b of the sheath 5 and the inner resin molded body 30 provided inside the electric wire accommodating portion 14, and the end surface 5b of the sheath 5 is formed on the inner resin molded body 30. Not in contact.

The cable terminal structure in the present embodiment can be manufactured by, for example, the following manufacturing method.

First, the end of the cable is housed in the holder 10. Specifically, as shown in FIG. 3, the end portion 5a of the sheath 5 and the root portions 3a, 4a of the insulated wires 3 and 4 protruding from the end portion 5a are placed at predetermined positions on the lower holder member 11. Place it. Next, the upper holder member 12 is superposed on the lower holder member 11 on which the end portion 5a of the sheath 5 and the root portions 3a and 4a of the insulated wires 3 and 4 are placed, and both members 11 and 12 are butted against each other. By this step, the holder 10 including the sheath accommodating portion 13 and the electric wire accommodating portion 14 is formed, the end portion 5a of the sheath 5 is accommodated in the sheath accommodating portion 13, and the roots of the insulated wires 3 and 4 are accommodated in the electric wire accommodating portion 14. Parts 3a, 4a are accommodated.

Next, the inner resin molded body 30 (FIG. 2) and the outer resin molded body 31 (FIG. 5) are molded by the same step. Specifically, as shown in FIG. 6, the holder 10 in which the end of the cable is housed is arranged in the cavity 41 of the mold 40.

Next, the heat-melted resin material is supplied into the cavity 41 in which the holder 10 is arranged to mold the outer resin molded body 31 (FIG. 5). At the same time, a part of the resin material supplied into the cavity 41 is filled inside the holder 10 (electric wire accommodating portion 14) through the through hole 15 provided in the lower holder member 11, and the inner resin molded body 30 ( FIG. 2) is molded. At this time, since the wire accommodating portion 14 and the sheath accommodating portion 13 of the holder 10 are separated by the wall portion 20, the resin material flowing into the electric wire accommodating portion 14 from the through hole 15 does not come into contact with the end surface 5b of the sheath 5. It does not enter the gap between the sheath 5 and the insulated wires 3 and 4. In this embodiment, polyphthalamide (PPA) or polyphenylene sulfide (PPS) was used as the material for the inner resin molded body 30 and the outer resin molded body 31.

By this step, an outer resin molded body 31 (FIG. 5) covering at least a part of the holder 10 and a part of the sheath 5 protruding from the holder 10 is molded on the outside of the holder 10 and inside the holder 10. The inner resin molded body 30 (FIG. 2) covering the root portions 3a and 4a of the insulated wires 3 and 4 is molded. That is, the outer resin molded body 31 and the inner resin molded body 30 are molded at the same time. Further, due to the heat of the resin material supplied into the cavity 41, the surface layer portions of the holder 10 and the sheath 5 covered with the outer resin molded body 31 are appropriately melted and bonded to the outer resin molded body 31. Similarly, due to the heat of the resin material, the surface layer portion of the insulating layer 7 of the insulating wires 3 and 4 covered with the inner resin molded body 30 is also appropriately melted and bonded to the inner resin molded body 30. As a result, the waterproofness of the cable end is ensured.

Here, the melting point of polyphthalamide (PPA) is about 320 ° C., and the melting point of polyphenylene sulfide (PPS) is about 290 ° C., which is higher than the melting point of urethane forming the insulating layer 7 of the insulated wires 3 and 4. high. However, the resin material (PPA or PPS) supplied into the cavity 41 does not immediately touch the insulated wires 3 and 4 (insulating layer 7), and the holder is passed through the through hole 15 provided in the lower holder member 11. After filling the inside of 10, the insulating wires 3 and 4 (insulating layer 7) are touched. Further, the amount of the resin material that comes into contact with the insulating wires 3 and 4 (insulating layer 7) is smaller than the total amount of the resin material supplied into the cavity 41. Therefore, even if the outer resin molded body 31 and the inner resin molded body 30 are molded using a resin material having a melting point higher than that of urethane, damage to the insulated wires 3 and 4 (insulating layer 7) due to the heat of the resin material is reduced. can.

Further, in the present embodiment, the resin supply port (gate) 42 of the cavity 41 and the opening (through hole 15) of the holder 10 are separated from each other. Specifically, as shown in FIG. 6, the resin supply port (gate) 42 is provided on the side surface of the cavity 41. Therefore, the holder 10 is arranged in the cavity 41 so that the bottom surface provided with the through hole 15 (the bottom surface of the lower holder member 11) faces the bottom surface of the cavity 41. Therefore, the resin material that has flowed into the cavity 41 from the resin supply port (gate) 42 does not directly flow into the holder 10, and damage to the insulated wires 3 and 4 (insulating layer 7) can be reduced more reliably. ..

It is clear that the above effect can be obtained by keeping the resin supply port (gate) 42 of the cavity 41 and the through hole 15 of the holder 10 as far as possible. Therefore, it is preferable to appropriately change the position and orientation of the holder 10 according to the position of the resin supply port (gate) 42.

Then, by taking out the resin-molded holder 10 from the cavity 41, the cable terminal structure according to the present embodiment is manufactured.

The present invention is not limited to the above embodiment, and various modifications can be made without changing the gist thereof. For example, the cable 1 is not limited to a two-core cable, and may be a single-core cable or a cable having three or more cores. Further, the opening of the holder 10 may be provided in the upper holder member, and the position thereof is not limited to the position shown in the drawing. For example, an opening may be provided on the upper surface or the side surface of the holder 10.

Further, the material of the inner resin molded body 30 and the outer resin molded body 31 is not limited to polyphthalamide (PPA) or polyphenylene sulfide (PPS).

1 Cable 3, 4 Insulated wire 3a, 4a Root part 5 Sheath 5a End 5b End face 6 Conductor 7 Insulation layer 10 Holder 11 Lower holder member 12 Upper holder member 13 Sheath housing 14 Wire housing 15 Through hole 20 Wall 21 Hole 22 Lower side wall 23 Upper side wall 24 Recess 30 Inner resin molded body 31 Outer resin molded body 40 Mold 41 Cavity 42 Resin supply port

Claims (9)

It is a terminal structure of a cable having an insulated wire and a sheath provided around the insulated wire.
A holder for accommodating the end of the sheath and the root of the insulated wire protruding from the end face of the sheath.
An outer resin molded body provided on the outside of the holder and covering at least a part of the holder and a part of the sheath protruding from the holder.
An inner resin molded body provided inside the holder and covering the root portion of the insulated wire,
Have,
The outer resin molded body and the inner resin molded body are connected and integrated through an opening provided in the holder.
The holder protrudes from the outer resin molded body, and the insulated wire extends from the holder protruding from the outer resin molded body.
Cable terminal structure. In the cable terminal structure according to claim 1,
Inside the holder, a wall portion interposed between the end face of the sheath and the inner resin molded body is provided.
The root portion of the insulated wire penetrates the wall portion.
Cable terminal structure. In the cable terminal structure according to claim 2,
The holder is formed by a lower holder member and an upper holder member that are abutted against each other from both radial sides of the cable.
The wall portion is formed by a lower side wall portion formed on the lower holder member and an upper side wall portion formed on the upper holder member.
A recess for receiving the root portion of the insulated wire is formed on the end faces of the lower side wall portion and the upper side wall portion that are butted against each other.
Cable terminal structure. In the cable terminal structure according to claim 3,
The opening is a through hole provided in the lower holder member or the upper holder member.
Cable terminal structure. In the cable terminal structure according to any one of claims 1 to 4.
The sheath is formed of urethane, and the outer resin molded body and the inner resin molded body are formed of polyphthalamide or polyphenylene sulfide.
Cable terminal structure. A method for manufacturing a terminal structure of a cable having an insulated wire and a sheath provided around the insulated wire.
A step of accommodating the end portion of the sheath and the root portion of the insulated wire protruding from the end face of the sheath in the holder.
A step of molding an outer resin molded body that covers at least a part of the holder and a part of the sheath protruding from the holder on the outside of the holder.
A step of forming an inner resin molded body that covers the root portion of the insulated wire inside the holder, and a step of forming the inner resin molded body.
Have,
The holder protrudes from the outer resin molded body, and the insulated wire extends from the holder protruding from the outer resin molded body.
Manufacturing method of cable terminal structure. In the method for manufacturing a cable terminal structure according to claim 6,
The outer resin molded body and the inner resin molded body are molded in the same process.
Manufacturing method of cable terminal structure. In the method for manufacturing a cable terminal structure according to claim 7,
The holder containing the end portion of the sheath and the root portion of the insulated wire is placed in the cavity of the mold.
The molten resin material is supplied into the cavity in which the holder is arranged to form the outer resin molded body.
A part of the resin material supplied into the cavity is filled inside the holder through an opening provided in the holder to form the inner resin molded product.
Manufacturing method of cable terminal structure. In the method for manufacturing a cable terminal structure according to any one of claims 6 to 8.
When the sheath is made of urethane, the outer resin molded body and the inner resin molded body are molded with polyphthalamide or polyphenylene sulfide.
Manufacturing method of cable terminal structure.

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