JP2021044207A - Cable module and method for manufacturing the same - Google Patents

Abstract

To improve manufacturing easiness of a fixing part that collectively fixes a plurality of oblong cables.SOLUTION: A method for manufacturing a cable module includes a process of arranging a part of each of a plurality of cables in a first space and sandwiching the plurality of cables between an upper mold and a lower mold so as to form a second space communicating with the first space in a longitudinal direction. The method for manufacturing the cable module includes: a process of injecting a resin from the second space into the first space; a process of curing the resin; and a process of forming a first structure which is made of the resin poured into the first space by removing the upper mold and the lower mold, and a second structure which is made of the resin poured into the second space and is integrally formed with the first structure. Further, the method for manufacturing the cable module includes a process of forming the fixing part which is composed of the first structure by removing the second structure integrally formed with the first structure.SELECTED DRAWING: Figure 7

Description

The present invention relates to a cable module and a manufacturing technique thereof, and for example, a cable module for fixing a part of each of a plurality of cables together and a technique effective when applied to the manufacturing technique thereof.

Japanese Unexamined Patent Publication No. 2012-190570 (Patent Document 1) describes a technique for fixing a plurality of round insulated wires arranged in parallel with each other by a connecting fixing portion.

Japanese Unexamined Patent Publication No. 2012-190570

When connecting a plurality of cables to a printed circuit board or a connector component, it is complicated to connect the cables individually to the printed circuit board or the connector component. For this reason, it has been studied to configure a cable module by fixing a plurality of cables together, and to connect each cable constituting the cable module to a printed circuit board or a connector component at once. In this regard, for example, a fixing portion for fixing a plurality of cables together may be molded by a so-called molding technique in which resin is injected into a space sandwiched between an upper mold and a lower mold. However, the present inventor needs to devise a method for pouring resin when molding a fixing portion for collectively fixing a plurality of cables having an oval cross-sectional shape orthogonal to the longitudinal direction by a molding technique. Was newly found. In other words, when molding a fixed part that fixes a plurality of oval-shaped cables together using molding technology, it is desirable to devise a way to suppress molding defects of the fixed part due to poor resin filling. It is rare.

Other challenges and novel features will become apparent from the description and accompanying drawings herein.

The method of manufacturing the cable module in the embodiment includes a step of preparing an upper mold and a lower mold, arranging a part of each of a plurality of cables in the first space, and communicating with the first space in the longitudinal direction. This includes a step of sandwiching a plurality of cables between the upper mold and the lower mold so that the second space is formed. The method of manufacturing the cable module in the embodiment is as follows: a step of injecting resin from the second space into the first space, a step of curing the resin, and a step of removing the upper mold and the lower mold to remove the first space. The present invention includes a step of forming a first structure made of the resin poured into the first structure and a second structure made of the resin poured into the second space and integrally formed with the first structure. Further, the method of manufacturing a cable module in the embodiment includes a step of forming a fixed portion made of the first structure by removing the second structure integrally formed with the first structure.

Further, the cable module according to the embodiment includes a plurality of cables having an oval cross-sectional shape orthogonal to the longitudinal direction, and a fixing portion for fixing a part of each of the plurality of cables together. At this time, the fixing portion is composed of a main body portion in a state in which the resin injection portion is removed from the integrated structure including the main body portion and the resin injection portion. Each of the plurality of cables has a plurality of conductor wires, an insulating layer covering the plurality of conductor wires, a shield layer covering the insulating layer, and a sheath covering the shield layer. Here, the fixing portion includes one side surface through which a plurality of cables penetrate, and one side surface has a separating surface formed by removing the resin injection portion from the main body portion.

According to one embodiment, when a fixed portion for fixing a plurality of oval-shaped cables together is molded by a molding technique, it is possible to suppress a molding defect of the fixed portion due to a resin filling defect.

It is a figure which shows the multi-core cable which functions as a cable for differential signal transmission. It is a figure explaining the structure of the end part of a multi-core cable. Pre-solder technology is used to form a solder layer on the surface of the conductor wire exposed in the exposed area of the conductor wire of the multi-core cable and the surface of the shield layer exposed in the exposed area of the shield layer of the multi-core cable. It is a figure which shows typically the state of being done. It is a figure which shows the structure of the cable module in the related technology. It is a figure which shows typically the space created by sandwiching a part of a plurality of multi-core cables arranged in parallel with each other by an upper mold and a lower mold. FIG. 5 is a cross-sectional view taken along the line AA of FIG. It is a flowchart for demonstrating the flow of the mold molding process which forms the fixing part in embodiment. It is a figure which shows typically the state which the 1st space and the 2nd space are formed by sandwiching a plurality of multi-core cables together by the upper mold and the lower mold. It is sectional drawing cut along the line AA of FIG. It is sectional drawing cut along the line BB of FIG. A state in which a resin is filled in the first space and the second space defined by combining the upper mold and the lower mold, the resin is cured, and then the upper mold and the lower mold are removed. It is a schematic diagram which shows. It is a figure which shows the structure of the cable module in embodiment. It is a figure which shows the structure of the cable module which consists of a plurality of coaxial cables. It is a figure which shows typically the space created by sandwiching a part of a plurality of coaxial cables arranged in parallel with each other by an upper mold and a lower mold. It is sectional drawing cut along the line AA of FIG. It is a figure which shows the stranded wire schematically. It is a figure for demonstrating the technical difficulty which becomes apparent when molding a fixed part which holds a stranded wire by a molding technique.

In all the drawings for explaining the embodiment, the same members are, in principle, given the same reference numerals, and the repeated description thereof will be omitted. In addition, in order to make the drawing easy to understand, hatching may be added even if it is a plan view.

<Cable module using coaxial cable>
FIG. 13 is a diagram showing a configuration of a cable module composed of a plurality of coaxial cables.

As shown in FIG. 13, the cable module 100 has a plurality of coaxial cables 1. Briefly, the coaxial cable 1 is composed of a core wire (inner conductor), an insulating layer covering the core wire, an outer conductor covering the surface of the insulating layer, and a protective coating covering the outer conductor. Then, the plurality of coaxial cables 1 are collectively fixed by the fixing portion 10. At this time, the cutting portion 10a exists on the upper surface of the fixing portion 10. This is because the fixing portion 10 is made of resin and is molded by a so-called molding technique in which the resin is injected into the space sandwiched between the upper mold and the lower mold, and the resin formed by the molding technique. This is because the fixing portion 10 is formed by cutting the. That is, the cutting portion 10a existing on the upper surface of the fixing portion 10 shown in FIG. 13 is a trace generated when the fixing portion 10 is formed.

Hereinafter, a step of molding the fixed portion 10 by using the molding technique will be described.

FIG. 14 is a diagram schematically showing a space created by sandwiching a part of a plurality of coaxial cables arranged so as to be parallel to each other between an upper mold and a lower mold.

In FIG. 14, the fixing portion is formed by injecting the resin into the space SP.

Specifically, FIG. 15 is a cross-sectional view taken along the line AA of FIG. However, FIG. 15 also shows an upper mold 200 and a lower mold 300 not shown in FIG.

As shown in FIG. 15, by arranging the upper mold 200 on the lower mold 300, the space SP sandwiched between the upper mold 200 and the lower mold 300 is defined. Then, a part of each of the plurality of coaxial cables 1 is arranged inside the space SP. A gate 200a, which is a resin injection port, is provided on the upper part of the upper mold 200, and the resin is formed inside the space SP sandwiched between the upper mold 200 and the lower mold 300 from the gate 200a. Infused. In FIG. 15, the arrow indicates the injection state of the resin injected from the gate 200a into the space SP.

Here, as shown in FIG. 15, in the coaxial cable 1, since the cross-sectional shape orthogonal to the longitudinal direction (y direction) is circular, a narrow gap region sandwiched between the coaxial cable 1 and the lower mold 300 is formed. The width of 11 in the x direction becomes shorter. As a result, the resin injected into the space SP from the gate 200a can smoothly pass through the narrow gap region 11 having a short width in the x direction. Therefore, when the fixing portion for fixing each part of the plurality of coaxial cables 1 is molded by the molding technique, the space SP sandwiched between the upper mold 200 and the lower mold 300 can be filled with the resin without any problem. As a result, in a cable module in which a plurality of coaxial cables 1 are bundled by a fixed portion, the fixed portion can be molded by a molding technique.

However, when the cable module 100 shown in FIG. 13 is used for differential transmission, a decrease in transmission characteristics of the differential signal becomes apparent. This is because the cable module 100 shown in FIG. 13 is composed of a plurality of coaxial cables 1, and when the plurality of coaxial cables 1 are used as the differential signal transmission cable, a pair of coaxial cables constituting the differential signal transmission cable are used. This is because the cable lengths are easily different between the cables 1, and as a result, the skew (phase difference) in the differential signal increases, and the transmission characteristics of the differential signal deteriorate. That is, the cable module 100 composed of a plurality of coaxial cables 1 is not suitable as a differential signal transmission cable for transmitting a differential signal.

<Cable module using stranded wire>
Therefore, as a differential signal transmission cable for transmitting a differential signal, a "twinax cable", which is a stranded wire obtained by twisting a pair of signal wires, is often used.

FIG. 16 is a diagram schematically showing a stranded wire.

In FIG. 16, the stranded wire 2 has an electric wire 2a composed of an insulating layer covering the conductor wire 20a and the conductor wire 20a, and an electric wire 2b composed of an insulating layer covering the conductor wire 20b and the conductor wire 20b. And the electric wire 2b are twisted together. In the stranded wire 2 configured in this way, the lengths of the electric wires 2a and the electric wires 2b twisted to each other are substantially the same. Therefore, when the stranded wire 2 is used as the differential signal transmission cable for transmitting the differential signal, skew in the differential signal can be suppressed, and as a result, deterioration of the transmission characteristic of the differential signal can be suppressed.

Then, a cable module is configured by collectively fixing a plurality of stranded wires 2 useful as a cable for differential signal transmission, and a printed circuit board or a connector is collectively attached to each stranded wire 2 constituting the cable module. It is being considered to connect to parts. Regarding this point, for example, the fixing portion for fixing the plurality of stranded wires 2 together may be molded by a so-called molding technique in which resin is injected into the space sandwiched between the upper mold and the lower mold. That is, with respect to the stranded wire 2, it is conceivable to mold the fixed portion that holds the stranded wire 2 together by a molding technique, similarly to the coaxial cable 1. However, unlike the coaxial cable 1, the stranded wire 2 has a pair of electric wires (electric wire 2a and electric wire 2b) twisted to each other. Therefore, because the cable structure of the stranded wire 2 is different from the cable structure of the coaxial cable 1, in order to mold the fixed portion for tying the stranded wire 2 by the molding technique, the fixed portion for tying the coaxial cable is required. Technical difficulties that did not pose a problem when molding with molding technology become apparent.

This point will be described below.

FIG. 17 is a diagram for explaining the technical difficulty that becomes apparent when the fixed portion that holds the stranded wires is molded by the molding technique.

In FIG. 17, a plurality of stranded wires 2 are arranged side by side in the x direction, and each of the plurality of stranded wires 2 extends in the y direction, which is the longitudinal direction. As a result, for example, when the fixed portion for collecting the stranded wires 2 is molded by the molding technique, the plurality of stranded wires 2 are sandwiched between the upper mold and the lower mold in the fixed region 400 of FIG. The twist pitch of each of the wires 2 fluctuates slightly irregularly in the longitudinal direction. This makes it difficult to design a support structure for the molds (upper mold and lower mold) for supporting the stranded wire 2 in the fixed region 400. In this regard, if the stranded wire 2 is forcibly sandwiched between inconsistent dies, the stranded wire 2 may be crushed and resin may leak from the mold.

As described above, when the fixed portion for gathering the stranded wires 2 is molded by the molding technique, the twist pitch of the stranded wires 2 itself fluctuates irregularly, which makes it difficult to design the mold. That is, as shown in FIG. 17, the plurality of stranded wires 2 are supported by the mold in the fixed region 400, but the design of the mold becomes difficult due to the minute and irregular fluctuation of the twist pitch.

Therefore, the stranded wire 2 is useful as a cable for transmitting a differential signal for transmitting a differential signal, but the stranded wire 2 is bundled with respect to forming a cable module by fixing a plurality of stranded wires 2 together. Since it is difficult to mold the fixed portion by the molding technique, some ingenuity is required to realize a cable module composed of a plurality of stranded wires 2.

In this regard, for example, it is conceivable to manufacture the cable module by laminating the entire plurality of stranded wires 2 instead of manufacturing the cable module by a fixing portion that holds a part of each of the plurality of stranded wires 2 together. However, in the cable module formed by laminating the entire plurality of stranded wires 2, the cable module itself becomes rigid and the degree of freedom of bending is reduced. In particular, for example, when the attachment angles of the connectors attached to both ends of the cable module are different, it is necessary to bend the cable module, and it is difficult to deal with the cable module formed by laminating the entire plurality of stranded wires 2. Become. For this reason, in order to secure the bending characteristics (bending degree of freedom) of the cable module, it is desirable to manufacture the cable module by a fixing portion that holds a part of each of the plurality of stranded wires 2 together. However, as described above, when the cable module is manufactured by the fixing portion that holds a part of each of the plurality of twisted wires 2, it is technically difficult to mold the fixing portion that holds the twisted wires 2 together by the molding technique. Exists. That is, it is difficult to form a cable module by collectively fixing a plurality of stranded wires 2 useful as a differential signal transmission cable and to secure the bending characteristics of the cable module.

<Adoption of multi-core cable>
From the above, a cable module that collectively fixes a part of each of a plurality of coaxial cables is useful in that a molding technique can be used when molding a fixing portion that bundles a plurality of coaxial cables. A cable module composed of a coaxial cable is not suitable for use as a differential signal transmission cable for transmitting a differential signal.

On the other hand, unlike a coaxial cable, a stranded wire is useful as a cable for transmitting a differential signal for transmitting a differential signal, but in the case of manufacturing a cable module in which a part of each of a plurality of stranded wires is fixed together. , It becomes difficult to use the molding technique when molding the fixed portion that holds a plurality of stranded wires together. Therefore, the coaxial cable and the stranded wire have advantages and disadvantages, respectively, and have both the usefulness as a cable for transmitting a differential signal for transmitting a differential signal and the usefulness for molding a fixed portion by a molding technique. It cannot be said that it is the best cable.

Therefore, the present inventor is considering adopting a cable different from the coaxial cable and the stranded wire. That is, the present inventor has studied a multi-core cable as a cable that has both the usefulness as a cable for transmitting a differential signal for transmitting a differential signal and the usefulness of being able to mold a fixed portion by a molding technique. doing.

In the following, first, the configuration of this multi-core cable will be described.

<Multi-core cable configuration>
FIG. 1 is a diagram showing a configuration of a multi-core cable 3 that functions as a differential signal transmission cable.

In FIG. 1, the multi-core cable 3 has a pair of conductor wires 30a and conductor wires 30b that function as signal lines through which differential signals propagate, an insulating layer 31 that covers the periphery of the conductor wires 30a and the conductor wires 30b, and an insulating layer. It has a shield layer 32 that covers the periphery of the shield layer 32 and a protective layer 33 that covers the periphery of the shield layer 32.

Each of the conductor wire 30a and the conductor wire 30b is composed of, for example, a copper wire or a copper alloy wire. On the other hand, the insulating layer 31 is made of, for example, a polyethylene resin or a fluororesin. Further, the shield layer 32 is composed of, for example, a plating layer made of copper.

On the other hand, the protective layer 33 has, for example, a structure in which an insulating tape is spirally wound around the outer periphery of the shield layer 32. At this time, the tape has a structure in which a flexible insulating resin layer such as polyethylene terephthalate (PET) and an adhesive layer containing an adhesive are laminated. The tape is spirally wound around the outer circumference of the shield layer 32 so that the adhesive layer is on the inside and the resin layer is on the outside. The protective layer 33 may be formed by extruding or applying a resin such as a polyurethane resin, an acrylic resin, a polyester resin, or a polyimide resin to the outer periphery of the shield layer 32.

The shield layer 32 may be formed by vertically wrapping a metal foil tape (copper tape) around the outer periphery of the insulating layer 31, but in recent years, the transmission characteristics of signals propagating through the conductor wire 30a and the conductor wire 30b have been improved. From the viewpoint of improvement, it is considered to form the shield layer 32 from the plating layer instead of the metal foil tape.

Hereinafter, the reason why the transmission characteristics of the signals propagating through the conductor wire 30a and the conductor wire 30b are improved when the shield layer 32 is composed of the plating layer will be described first.

For example, when the shield layer 32 is made of a metal foil tape, the metal foil tape is not fixed to the insulating layer 31, so that the metal foil tape tends to loosen. If the metal foil tape is loosened, a gap may be formed between the insulating layer 31 and the shield layer 32.

In this regard, if there is a gap between the insulating layer 31 and the shield layer 32, a phase difference occurs between the signal propagating the conductor wire 30a and the signal propagating the conductor wire 30b. This phenomenon is called inward skew, and when inward skew occurs, the transmission characteristics of the differential signal propagating through the multi-core cable 3 deteriorate. Therefore, in order to improve the transmission performance of the multi-core cable 3, it is considered to fix the shield layer 32 to the insulating layer 31 so that a gap is not formed between the insulating layer 31 and the shield layer 32. .. Specifically, it is being studied to form the shield layer 32 from a plating layer instead of forming it from a metal foil tape. For example, by using an electroless plating method, a plating layer can be formed on the surface of the insulating layer 31. At this time, since the plating layer is formed so as to be fixed to the insulating layer 31, a gap is generated between the insulating layer 31 and the shield layer 32 according to the configuration in which the shield layer 32 is formed from the plating layer. Can be suppressed. As a result, according to the multi-core cable 3 in which the shield layer 32 is formed from the plating layer, the phase shift of the signal due to the gap can be suppressed, so that the transmission characteristic of the differential signal propagating through the multi-core cable 3 can be improved. Can be done. For the above reasons, it can be seen that the transmission characteristics of the signals propagating through the conductor wire 30a and the conductor wire 30b can be improved by forming the shield layer 32 from the plating layer instead of the metal foil tape.

Further, when the shield layer 32 is composed of a plating layer, the film thickness of the shield layer 32 can be reduced as compared with the case where the shield layer 32 is composed of a metal foil tape. From this, according to the multi-core cable 3 in which the shield layer 32 is composed of a plating layer, there is also an advantage that the diameter and weight of the multi-core cable 3 can be reduced.

<Cable end configuration>
In the multi-core cable 3 described above, the conductor wire 30a, the conductor wire 30b, and the shield layer 32 are each connected to a printed circuit board or a connector at both ends. Therefore, the end of the multi-core cable 3 is processed so that each of the conductor wire 30a, the conductor wire 30b, and the shield layer 32 can be connected to the printed circuit board or the connector.

Hereinafter, the configuration of the end portion of the multi-core cable 3 processed so as to be connected to a printed circuit board or a connector will be described with reference to the drawings.

FIG. 2 is a diagram illustrating a configuration of an end portion of the multi-core cable 3.

In FIG. 2, a connection area 500 for connecting the multi-core cable 3 to a printed circuit board or a connector is provided at the end of the multi-core cable 3. The connection region 500 is composed of a conductor wire exposed region 501 in which the conductor wire 30a and the conductor wire 30b are exposed, and a shield layer exposed region 502 in which the shield layer 32 is exposed. Then, the multi-core cable 3 is electrically connected to the printed circuit board or the connector by connecting each of the conductor wire exposed area 501 and the shield layer exposed area 502 to the printed circuit board or the connector. Specifically, the multi-core cable 3 is electrically connected to the printed circuit board or the connector by solder-connecting each of the conductor wire exposed area 501 and the shield layer exposed area 502 to the printed circuit board or the connector.

Here, for example, FIG. 3 shows the surfaces of the conductor wires 30a and 30b exposed in the conductor wire exposed region 501 of the multi-core cable 3 and the shield layer exposed region 502 of the multi-core cable 3. It is a figure which shows typically the appearance that the solder layer is formed on the surface of a shield layer 32. In particular, in FIG. 3, the region drawn by using dots indicates that a solder layer is formed. As described above, the surfaces of the conductor wires 30a and 30b exposed in the conductor wire exposed region 501 of the multi-core cable 3 and the surface of the shield layer 32 exposed in the shield layer exposed region 502 of the multi-core cable 3 A solder layer is formed on the surface.

<Necessity of ingenuity for multi-core cable>
For example, as shown in FIG. 1, the inside of one multi-core cable 3 includes a conductor wire 30a and a conductor wire 30b, and the length of the conductor wire 30a and the length of the conductor wire 30b are approximately the same. equal. Therefore, by transmitting the differential signal using the conductor wire 30a and the conductor wire 30b included in the single multi-core cable 3, the skew (phase difference) in the differential signal can be suppressed, and as a result, the differential is differential. The signal transmission characteristics of the signal can be improved, that is, the multi-core cable 3 is suitable as a differential signal transmission cable for transmitting a differential signal.

On the other hand, unlike the stranded wire 2, the multi-core cable 3 is not twisted. Therefore, even in the case where a plurality of multi-core cables 3 are assembled to form a cable module, it is considered that the molding technique can be used when forming the fixing portion for integrating the plurality of multi-core cables 3.

From this, it is considered that the multi-core cable 3 has both the usefulness as a cable for transmitting a differential signal for transmitting a differential signal and the usefulness of being able to mold a fixed portion by a molding technique. .. However, as shown in FIG. 1, the multi-core cable 3 has an oval shape in cross section orthogonal to the longitudinal direction (y direction), for example. Then, the present inventor needs to devise a resin pouring when molding a fixing portion for collectively fixing a plurality of multi-core cables 3 having an oval cross-sectional shape orthogonal to the longitudinal direction by a molding technique. I newly found that there is. That is, when molding a fixed portion for fixing a plurality of oval-shaped multi-core cables 3 together using the molding technique, in order to suppress the molding defect of the fixed portion due to the defective filling of the resin. Ingenuity is desired.

Therefore, in the following, first, the related technology relating to the cable module in which a plurality of multi-core cables 3 are assembled by the fixing portion formed by using the molding technology will be described, and then there is room for improvement existing in this related technology. Will be described. Then, the technical idea in the embodiment in which the room for improvement is devised will be described.

The term "oval shape" as used herein refers to a closed curve having a minor axis and a major axis, and is used in a broad concept including not only an elliptical shape but also a substantially elliptical shape and a compound elliptical shape. There is. In particular, the "oval shape" as used herein also includes a closed curve composed of two parallel straight lines facing each other and two arcs connecting the ends of the two straight lines.

<Room for improvement in related technologies>
The "related technology" referred to in the present specification is a technology having a problem newly found by the inventor, and is not a known conventional technology, but is intended as a prerequisite technology (unknown technology) of a new technical idea. It is a technique described in.

FIG. 4 is a diagram showing a configuration of a cable module in a related technique.

As shown in FIG. 4, the cable module 600 has a plurality of multi-core cables 3. The plurality of multi-core cables 3 are collectively fixed by the fixing portion 40. At this time, the cutting portion 40a exists on the upper surface of the fixing portion 40. This is because the fixing portion 40 is made of resin and is molded by a so-called molding technique in which the resin is injected into the space sandwiched between the upper mold and the lower mold, and the resin formed by the molding technique. This is because the fixing portion 40 is formed by cutting. That is, the cutting portion 40a existing on the upper surface of the fixing portion 40 shown in FIG. 4 is a trace generated when the fixing portion 40 is molded.

Hereinafter, a step of molding the fixed portion 40 by using the molding technique will be described.

FIG. 5 is a diagram schematically showing a space created by sandwiching a part of a plurality of multi-core cables arranged so as to be parallel to each other between an upper mold and a lower mold.

In FIG. 5, the fixing portion is formed by injecting the resin into the space SP2.

Specifically, FIG. 6 is a cross-sectional view taken along the line AA of FIG. However, FIG. 6 also shows an upper mold 50 and a lower mold 60 not shown in FIG.

As shown in FIG. 6, by arranging the upper mold 50 on the lower mold 60, the space SP2 sandwiched between the upper mold 50 and the lower mold 60 is defined. Then, a part of each of the plurality of multi-core cables 3 is arranged inside the space SP2. A gate 50a, which is a resin injection port, is provided on the upper part of the upper mold 50, and the resin is formed inside the space SP2 sandwiched between the upper mold 50 and the lower mold 60 from the gate 50a. Infused. In FIG. 6, the arrow indicates the injection state of the resin injected from the gate 50a into the space SP2.

Here, as shown in FIG. 6, in the multi-core cable 3, since the cross-sectional shape orthogonal to the longitudinal direction (y direction) is an oval shape, the multi-core cable 3 is sandwiched between the multi-core cable 3 and the lower mold 60. The width of the narrow gap region 41 in the x direction becomes long. As a result, the resin injected into the space SP2 from the gate 50a cannot smoothly pass through the narrow gap region 41 having a long width in the x direction. Therefore, in the related technology, when the fixing portion for fixing each part of the plurality of multi-core cables 3 is molded by the molding technique, the space SP2 sandwiched between the upper mold 50 and the lower mold 60 is filled with resin. Becomes difficult. That is, in the related technology, due to the peculiarity of the multi-core cable 3 that the cross-sectional shape of the multi-core cable 3 is an oval shape, a narrow gap region sandwiched between the multi-core cable 3 and the lower mold 300. The width of 41 in the x direction becomes longer. As a result, for example, as shown in FIG. 6, when the configuration of injecting the resin into the space SP2 from the gate 50a provided on the upper part of the upper mold 50 is adopted, the resin can be filled in the narrow gap region 41 without any gap. It becomes difficult. That is, there is room for improvement in the related technology from the viewpoint of filling the narrow gap region 41 with the resin without gaps. Furthermore, it is desirable that the thickness (height in the z direction) of the fixed portion molded by the molding technique is as thin as possible. Therefore, considering reducing the thickness of the fixed portion, the gap region 42 sandwiched between the multi-core cable 3 and the upper mold 50 also becomes narrower, and the resin cannot smoothly pass through this gap region 42 as well. .. That is, in order to make the thickness (height in the z direction) of the fixed portion molded by the molding technique as thin as possible, not only the narrow gap region 41 sandwiched between the multi-core cable 3 and the lower mold 60 but also the narrow gap region 41 is used. The gap region 42 sandwiched between the multi-core cable 3 and the upper mold 50 is also narrowed. Further, also in the gap region 42, it is considered that the resin filling defect becomes apparent due to the increase in the width of the gap region 42 in the x direction due to the cross-sectional shape of the multi-core cable 3 becoming an oval shape.

This is due to the fact that when the fixing portion for fixing a part of each of the plurality of multi-core cables 3 is molded by the molding technique, the cross-sectional shape of the multi-core cable 3 becomes an oval shape in the related technology. Increasing the width of each of the narrow gap region 41 and the gap region 42 in the x direction causes defective filling of the resin. Therefore, in the related technology, it is necessary to devise a method for suppressing the poor formation of the fixed portion due to the poor filling of the resin.

Therefore, in the present embodiment, a device is provided for the room for improvement existing in the related technology described above. Hereinafter, the technical idea in the present embodiment will be described.

<Molding process in the embodiment>
The cable module according to the present embodiment includes a plurality of multi-core cables having an oval cross-sectional shape orthogonal to the longitudinal direction, and a fixing portion for fixing a part of each of the plurality of multi-core cables together. The cable module according to the present embodiment configured as described above is manufactured by a method of manufacturing a cable module including a step of preparing a plurality of cables and a step of forming a fixing portion. At this time, in the step of molding the fixed portion in the present embodiment, the molding technique is used.

Hereinafter, the molding step of molding the fixed portion in the present embodiment will be described.

FIG. 7 is a flowchart for explaining the flow of the molding process of molding the fixed portion in the present embodiment. In addition, when explaining the flow of the molding process in FIG. 7, it will be described with reference to FIGS. 8, 9 and 11 which will be described later.

As shown in FIG. 7, first, an upper mold (upper mold 70 in FIG. 9) and a lower mold (lower mold 80 in FIG. 9) are prepared (S101). Then, a plurality of multi-core cables (multi-core cable 3 in FIG. 8) are collectively sandwiched between the upper mold (upper mold 70 in FIG. 9) and the lower mold (lower mold 80 in FIG. 9) (S102). Specifically, a part of each of the plurality of multi-core cables (multi-core cable 3 in FIG. 8) is arranged in the first space (first space SP3 in FIG. 8), and the first space (first space in FIG. 8) is arranged. The upper mold (upper mold 70 in FIG. 9) and the lower mold (lower in FIG. 9) are formed so as to form a second space (second space SP4 in FIG. 8) communicating with the 1 space SP3) in the longitudinal direction. A plurality of multi-core cables (multi-core cable 3 in FIG. 8) are sandwiched between the mold 80).

Subsequently, the resin is injected from the gate (gate 70a in FIG. 8) communicating with the second space (second space SP4 in FIG. 8) into the second space (second space SP4 in FIG. 8). At this time, since the second space (second space SP4 in FIG. 8) communicates with the first space (first space SP3 in FIG. 8), it passes through the second space (second space SP4 in FIG. 8). Then, the resin is also injected into the first space (first space SP3 in FIG. 8). As a result, the first space (first space SP3 in FIG. 8) and the second space (FIG. 8) sandwiched between the upper mold (upper mold 70 in FIG. 9) and the lower mold (lower mold 80 in FIG. 9). A resin is injected into the second space SP4) of 8 (S103).

Here, the resin is composed of, for example, polyamide (PA), which is a thermoplastic resin. However, the resin is not limited to this, and may be, for example, polypropylene, ethylene-vinyl acetate copolymer resin (EVA), or even a thermosetting resin.

Then, for example, when the resin is a thermoplastic resin, the first space (first space in FIG. 8) sandwiched between the upper mold (upper mold 70 in FIG. 9) and the lower mold (lower mold 80 in FIG. 9) is sandwiched between the upper mold (upper mold 70 in FIG. 9) and the lower mold (lower mold 80 in FIG. 9). After injecting the molten resin into the space SP3) and the second space (second space SP4 in FIG. 8), the first space (first space SP3 in FIG. 8) and the second space (second space SP4 in FIG. 8) are injected. ) Is cooled to cure the resin (S104). On the other hand, for example, when the resin is a thermosetting resin, the resin injected into the first space (first space SP3 in FIG. 8) and the second space (second space SP4 in FIG. 8) is heated. The resin is cured (S104).

Next, the upper mold (upper mold 70 in FIG. 9) and the lower mold (lower mold 80 in FIG. 9) are removed (S105). As a result, the first structure (first structure 95a in FIG. 11) made of resin poured into the first space (first space SP3 in FIG. 8) and the second space (second space SP4 in FIG. 8) A second structure (second structure 95b in FIG. 11) is formed, which is made of the resin poured into the water and is integrally formed with the first structure (first structure 95a in FIG. 11). .. After that, by removing the second structure (second structure 95b in FIG. 11) integrally formed with the first structure (first structure 95a in FIG. 11), the first structure (FIG. 11). A fixed portion (fixed portion 96 in FIG. 11) made of the first structure 95a) is formed (S106). Specifically, the first structure is formed by cutting the second structure (second structure 95b in FIG. 11) integrally formed with the first structure (first structure 95a in FIG. 11). A fixed portion (fixed portion 96 in FIG. 11) composed of a body (first structure 95a in FIG. 11) can be formed. As described above, the fixed portion (fixed portion 96 in FIG. 11), which is a component of the cable module in the present embodiment, can be manufactured by the molding technique.

Here, a process of sandwiching a plurality of multi-core cables together between the upper mold and the lower mold will be described.

FIG. 8 is a diagram schematically showing a state in which a first space SP3 and a second space SP4 are formed by sandwiching a plurality of multi-core cables together between the upper mold and the lower mold.

In FIG. 8, in order to represent the first space SP3 and the second space SP4 in an easy-to-understand manner, the upper mold and the lower mold itself are not shown and are formed by combining the upper mold and the lower mold. Only the first space SP3 and the second space SP4 are schematically shown. As shown in FIG. 8, in the present embodiment, by combining the upper mold and the lower mold, the second space SP4 communicating with the first space SP3 in the longitudinal direction (y direction) of the multi-core cable 3 is formed. The plurality of multi-core cables 3 are sandwiched between the upper mold and the lower mold so that a part of each of the plurality of multi-core cables 3 is arranged in the first space SP3 and the second space SP4.

Subsequently, resin is injected into the second space SP4 from the gate 70a communicating with the second space SP4 shown in FIG. 8, the second space SP4 is filled with the resin, and the first space communicating with the second space SP4 is further formed. A step of injecting resin from the second space SP4 into the SP3 and filling the first space SP3 with the resin will be described.

FIG. 9 is a cross-sectional view taken along the line AA of FIG. However, FIG. 9 also shows an upper mold 70 and a lower mold 80, which are not shown in FIG.

In FIG. 9, it can be seen that the plurality of multi-core cables 3 are sandwiched between the upper mold 70 and the lower mold 80. At this time, the inner surface 71 of the upper mold 70 defining the second space SP4 is separated from the upper surfaces of the plurality of multi-core cables 3, and the inner surfaces 81 of the lower mold 80 defining the second space SP4 are plural. It is in contact with the lower surface of each of the multi-core cables 3 of.

The resin is injected into the second space SP4 defined in this way from the gate 70a communicating with the upper mold 70. Specifically, as shown in FIG. 9, the resin flows from the gate 70a into the second space SP4 along the “−z direction”. Then, the resin flowing from the gate 70a into the second space SP4 along the "-z direction" is dispersed in the "+ x direction" and the "-x direction" and is filled to every corner inside the second space SP4. To. Here, in the plurality of multi-core cables 3, the multi-core cables 3 adjacent to each other are arranged at predetermined intervals so that the resin can easily flow.

Further, as shown in FIG. 9, the resin flowing into the second space SP4 communicates with the second space SP4 along the "−y direction" in the gap region 91 between the multi-core cables 3 adjacent to each other. It flows into one space. Here, the symbol shown in the gap region 91 represents the resin flow direction “−y direction” in the gap region 91.

FIG. 10 is a cross-sectional view taken along the line BB of FIG. However, FIG. 10 also shows an upper mold 70 and a lower mold 80, which are not shown in FIG.

Also in FIG. 10, it can be seen that the plurality of multi-core cables 3 are sandwiched between the upper mold 70 and the lower mold 80. At this time, the inner surface 71 of the upper mold 70 that defines the first space SP3 is separated from the plurality of multi-core cables 3, and the inner surface 81 of the lower mold 80 that defines the first space SP3 is also a plurality of multiple. It is separated from the core cable 3.

The resin is injected into the first space SP3 defined in this way from the second space SP4 which communicates with the first space SP3 in the longitudinal direction (y direction). Specifically, as shown in FIG. 10, through a plurality of gap regions 91 between the multi-core cables 3 adjacent to each other, along the "-y direction" from the second space SP4 to the first space SP3. Resin flows in. Then, the resin that has flowed into the first space SP3 is dispersed in the “+ x direction” and the “−x direction” from each of the plurality of gap regions 91, and the narrow gap region 92 and the narrow gap region 93 of the first space SP3 are dispersed. Flow into. In this way, according to the present embodiment, it is possible to fill every corner of the first space SP3 including the narrow gap region 92 and the narrow gap region 93 with the resin.

As shown in FIGS. 9 and 10, in the first space SP3, the distance between the inner surface 71 of the upper mold 70 and the upper surfaces of the plurality of multi-core cables 3 is shorter than that in the second space SP4. In other words, in the first space SP3, the space between the inner surface 71 of the upper mold 70 and the upper surfaces of the plurality of multi-core cables 3 is narrower than that in the second space SP4. On the other hand, as shown in FIGS. 9 and 10, in the first space SP3, the distance between the inner surface 81 of the lower mold 80 and the upper surfaces of the plurality of multi-core cables 3 is longer than that in the second space SP4. In other words, in the first space SP3, the space between the inner surface 81 of the lower mold 80 and the upper surfaces of the plurality of multi-core cables 3 is wider than that in the second space SP4.

Next, a step of forming a fixed portion in the present embodiment by cutting the cured resin will be described.

In FIG. 11, for example, the upper mold and the lower mold are shown after the resin is filled in the first space and the second space defined by combining the upper mold and the lower mold and the resin is cured. It is a schematic diagram which shows the state which removed the mold.

In FIG. 11, by removing the upper mold and the lower mold, the first structure 95a made of the resin poured into the first space and the first structure made of the resin poured into the second space are formed. A second structure 95b integrally formed with the 95a is formed. Then, for example, in FIG. 11, the second structure 95b integrally formed with the first structure 95a is cut and separated from the first structure 95a. Here, as a method for cutting the second structure 95b from the first structure 95a, for example, a blade such as a cutter, nippers, or a knife may be used, or the second structure 95b may be cut by a laser. As a result, the fixed portion 96 made of the first structure 95a can be formed. That is, the fixing portion 96 in the present embodiment is formed by cutting and separating the second structure 95b integrally molded with the first structure 95a on the side surface of the first structure 95a. As described above, the fixed portion 96 in the present embodiment can be molded by using the molding technique.

After applying the release agent to the surface of the multi-core cable 3 located in the second space, the molding step in the above-described embodiment can also be performed. In this case, when the second structure 95b is cut and separated from the first structure 95a, there is an advantage that the second structure 95b can be easily peeled off from the multi-core cable 3.

<Characteristics of manufacturing method in the embodiment>
Subsequently, the feature points in the manufacturing method in the present embodiment will be described.

The features of the manufacturing method in the present embodiment are, for example, as shown in FIGS. 8 to 10, a part of each of the plurality of multi-core cables 3 is arranged in the first space SP3, and the first space SP3 and the first space SP3. After sandwiching a plurality of multi-core cables 3 between the upper mold 70 and the lower mold 80 so that the second space SP4 communicating in the longitudinal direction is formed, resin is injected from the second space SP4 into the first space SP3. There is a point to do. As a result, for example, as shown in FIG. 10, through a plurality of gap regions 91 between the multi-core cables 3 adjacent to each other, along the "-y direction" from the second space SP4 to the first space SP3. The resin can be poured. Then, according to the characteristic point of the manufacturing method in the present embodiment, the resin flowing into the first space SP3 is dispersed in the “+ x direction” and the “−x direction” from each of the plurality of gap regions 91. It can flow into the narrow gap region 92 and the narrow gap region 93 of the first space SP3.

As a result, according to the present embodiment, even when the fixing portion for fixing the multi-core cable 3 having an oval cross-sectional shape orthogonal to the longitudinal direction is molded by the molding technique, the oval shape is formed. It is possible to effectively suppress the resin filling defect caused by the increase in the width of each of the narrow gap region 92 and the narrow gap region 93 in the x direction. Therefore, according to the present embodiment, it is possible to suppress poor formation of the fixed portion due to poor filling of the resin.

That is, in the manufacturing method feature points of the present embodiment, for example, as shown in FIG. 10, the second space SP4 to the first space pass through a plurality of gap regions 91 between the multi-core cables 3 adjacent to each other. The resin is allowed to flow along the "-y direction" toward SP3. This means that the plurality of gap regions 91 function as gates when the resin is injected into the first space SP3. That is, for example, in the related technique shown in FIG. 6, the resin is injected from only one gate 50a, whereas in the present embodiment shown in FIG. 10, a plurality of gap regions 91 at different locations are made to function as gates. There is. As a result, according to the present embodiment, it becomes easier to fill the resin in every corner of the first space SP3 than in the related technology (first advantage).

Further, in the feature points of the manufacturing method in the present embodiment, for example, the narrow gap region 92 of the first space SP3 and the narrow gap region 92 of the first space SP3 are dispersed from each of the plurality of gap regions 91 in the “+ x direction” and the “−x direction”. The resin can be injected into the narrow gap region 93. For example, in the related technique shown in FIG. 6, the resin can be injected into the narrow gap region 41 arranged in the right region of the gate 50a from only one direction in the “+ x direction”. Similarly, in the related technique shown in FIG. 6, the resin can be injected into the narrow gap region 41 arranged in the left region of the gate 50a from only one direction of the “−x direction”. On the other hand, according to the first feature point in the present embodiment, as shown in FIG. 10, in all the narrow gap regions 92 and the narrow gap regions 93, from both the “+ x direction” and the “−x direction”. Resin can be poured. As a result, according to the present embodiment, it is possible to effectively suppress poor filling of the resin in the narrow gap region 92 and the narrow gap region 93 as compared with the related technology (second advantage).

From the above, according to the characteristic points of the manufacturing method in the present embodiment, the plurality of oval-shaped multi-core cables 3 are fixed together by the synergistic effect of the first advantage and the second advantage described above. Even when the fixed portion 96 is molded by the molding technique, it is possible to obtain a remarkable effect that the poor formation of the fixed portion 96 can be effectively suppressed.

<Cable module configuration in the embodiment>
FIG. 12 is a diagram showing a configuration of a cable module according to the present embodiment.

In FIG. 12, the cable module 700 according to the present embodiment has a plurality of multi-core cables 3. The plurality of multi-core cables 3 are collectively fixed by the fixing portion 96. At this time, the cutting portion 97 exists on the side surface of the fixing portion 96. This is because the fixing portion 96 is made of resin and is molded by the molding technique of the present embodiment, and by cutting the resin formed by the molding technique of the present embodiment. This is because the fixing portion 96 is molded. That is, the cut portion 97 existing on the side surface of the fixed portion 96 shown in FIG. 12 is a trace generated when the fixed portion 96 is formed. The cut portion 97 can be distinguished from the other surface portions of the fixing portion 96. This is because, for example, the surface flatness of the cutting portion 97 cut by a sharp cutting jig is the flatness of the surface portion of the other fixing portion 96 formed by filling the mold formed by electric discharge machining with resin. This is because it is higher than sex. For example, by using a microscope or the like, it is possible to confirm the difference between the flatness of the cut portion 97 and the flatness of the surface portion of the other fixed portion 96.

<Structural features in the embodiment>
Next, structural features of the present embodiment will be described.

The structural feature of the present embodiment is, for example, that a cut portion 97 is formed on one side surface of the fixing portion 96 for fixing the plurality of multi-core cables 3 together, as shown in FIG. .. As a result, according to the cable module 700 in the present embodiment, the thickness of the fixing portion 96 in the z direction can be reduced.

For example, in the cable module 600 in the related technique shown in FIG. 4, a cutting portion 40a is formed on the upper surface of the fixing portion 40. Therefore, in the related technique, the thickness of the fixing portion 40 in the z direction is increased by the thickness of the cutting portion 40a.

On the other hand, in the cable module 700 of the present embodiment, as shown in FIG. 12, the cutting portion 97 is formed not on the upper surface of the fixing portion 96 but on one side surface. Therefore, in the cable module 700 of the present embodiment, the thickness of the fixed portion 96 in the z direction is not increased by the amount of the cut portion 97. From this, according to the present embodiment, the thickness of the fixed portion 96 in the z direction can be reduced as compared with the related technology.

Further, according to the present embodiment, the following advantages can be obtained due to the fact that the cut portion 97 is formed on one side surface of the fixing portion 96. That is, for example, the cable module 700 is connected to the printed circuit board or the connector with reference to the position of the molded fixing portion 96. Therefore, since the fixing portion 96 serves as a position reference when connecting the cable module 700 to the printed circuit board or the connector, it is important to improve the positioning accuracy of the fixing portion 96. In this regard, the second structure is cut from the integrally molded product of the first structure (main body portion) and the second structure (resin injection portion) that have been molded, and the fixing portion 96 composed of the first structure is formed. Therefore, a cutting site (separation site) 97, which is a trace of cutting and separating the second structure, is formed on one side surface of the fixing portion 96. At this time, when forming the cutting portion 97, if the position of the cutting portion 97 becomes the reference position when connecting the cable module 700 to the printed circuit board or the connector, the cable will be based on the position of the cutting portion 97. The module 700 can be easily mounted on a printed circuit board or a connector. That is, according to the structural feature point in the present embodiment that the cut portion 97 is formed on one side surface of the fixed portion 96, the cut portion 97 formed on the fixed portion 96 is mounted on the cable module 700. It can be used as a reference position.

Although the invention made by the present inventor has been specifically described above based on the embodiment thereof, the present invention is not limited to the embodiment and can be variously modified without departing from the gist thereof. Needless to say.

1 Coaxial cable 2 Twisted wire 2a Electric wire 2b Electric wire 3 Multi-core cable 10 Fixed part 10a Cutting part 20a Conductor wire 20b Conductor wire 30a Conductor wire 30b Conductor wire 31 Insulation layer 32 Shield layer 33 Protective layer 40 Fixed part 40a Cutting part 41 Area 42 Gap area 50 Upper mold 50a Gate 60 Lower mold 70 Upper mold 71 Inner surface 70a Gate 80 Lower mold 81 Inner surface 91 Gap area 92 Narrow gap area 93 Narrow gap area 95a First structure 95b Second structure 96 Fixed part 97 Cutting part 100 Cable module 200 Upper mold 200a Gate 300 Lower mold 400 Fixed area 500 Connection area 501 Conductor wire exposed area 502 Shield layer exposed area 600 Cable module

Claims (5)

Multiple cables whose cross-sectional shape is orthogonal to the longitudinal direction is oval,
A fixing portion for fixing a part of each of the plurality of cables together,
Is a method of manufacturing a cable module, which comprises
(A) Process of preparing the upper mold and the lower mold,
(B) With the upper mold so that a second space communicating with the first space in the longitudinal direction is formed, and a part of each of the plurality of cables is arranged in the first space and the second space. The process of sandwiching the plurality of cables with the lower mold,
(C) A step of injecting a resin into the first space via the second space.
(D) Step of curing the resin,
(E) By removing the upper mold and the lower mold,
A first structure made of the resin poured into the first space,
A second structure made of the resin poured into the second space and integrally formed with the first structure.
The process of forming
(F) A step of forming the fixed portion made of the first structure by removing the second structure integrally formed with the first structure.
How to make a cable module, including. In the method for manufacturing a cable module according to claim 1,
The inner surface of the upper mold that defines the first space is separated from the plurality of cables.
The inner surface of the lower mold that defines the first space is separated from the plurality of cables.
The inner surface of the upper mold that defines the second space is separated from the plurality of cables.
The inner surface of the lower mold that defines the second space comes into contact with the plurality of cables.
How to manufacture a cable module. Multiple cables whose cross-sectional shape is orthogonal to the longitudinal direction is oval,
A fixing portion for fixing a part of each of the plurality of cables together,
With
The fixing portion is a cable module composed of the main body portion in a state in which the resin injection portion is removed from an integral structure including the main body portion and the resin injection portion.
The fixing portion includes one side surface through which the plurality of cables penetrate.
A cable module having a separation portion formed by removing the resin injection portion from the main body portion on one side surface. In the cable module according to claim 3,
Each of the plurality of cables
With multiple conductor wires,
An insulating layer covering the plurality of conductor wires and
A shield layer that covers the insulating layer and
A protective layer that covers the shield layer and
Have,
Each of the plurality of cables has an end region and
The end area
The conductor wire exposed area where the plurality of conductor wires are exposed and the conductor wire exposed area
The shield layer exposed area where the shield layer is exposed and
Including
The fixing portion is a cable module arranged apart from the end region. In the cable module according to claim 4,
A cable module in which a solder layer is formed on the surface of each of the plurality of conductor wires formed in the conductor wire exposed region and on the surface of the shield layer formed in the shield layer exposed region.

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