JP3411366B2 - Waterproofing method of wire harness branch branch and processing apparatus therefor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproofing method for a branching portion of a wire harness branch line for branching a branch line from a main line of a wiring harness for a vehicle, and a processing apparatus therefor.

[0002]

2. Description of the Related Art Conventionally, various methods for waterproofing a branch portion of a wire harness branch line for branching a branch line from a main line of a wiring harness for a vehicle have been considered. Examples thereof are Japanese Patent Publication No. 4-47432 and Japanese Patent Publication No. 4-47433.
The methods disclosed in these publications will be described below.

As shown in FIG . 14 , Japanese Patent Publication No. 4-47.
In the method disclosed in Japanese Patent No. 432, the joint portion 104 between the electric wire 100 and the electric wire 102 is covered with a covering material 106, and the covering material 106 is a releasable support made of a plastic molding capable of transmitting ultraviolet rays. Inside the body 108,
It holds the sealing agent 110 which is solidified in the form of jelly. Note that FIG. 14 shows a state in which the support 108 is opened. Further, the sealing agent 110 is an ultraviolet curable resin composition, and after filling the inside of the support 108 with the sealing agent 110, the support 108 is closed and ultraviolet rays are radiated from the outside to seal the sealing agent. 110
Is being cured.

Further, in the method disclosed in Japanese Patent Publication No. 4-47433, a foam hot melt agent is used in place of the UV-curable resin composition as the sealant 110.

[0005]

However, in these methods, after the support 108 is filled with the sealing agent 110 composed of the ultraviolet curable resin composition or the hot melt agent, the support 108 is sealed and irradiated with ultraviolet rays. Alternatively, the sealant 110 is hardened by cooling. Therefore, when the sealing agent 110 hardens, a negative pressure is generated in the support 108 due to the volume contraction of the sealing agent 110, and the electric wires 100, 1
Air may enter the joint 104 from between the core wire of 02 and the coating. For this reason, the insulation strength and the waterproof performance may be reduced, and in the method of using the ultraviolet curable resin composition, the material cost and the equipment cost are expensive.

In view of the above facts, an object of the present invention is to provide a waterproof treatment method for a branch portion of a wire harness branch and a processing apparatus therefor capable of improving insulation strength and waterproof performance.

[0007]

According to a first aspect of the present invention, there is provided a waterproofing method for a branch portion of a wire harness branch line, which comprises a step of connecting a main wire and a branch wire of a wire harness covered with an insulating coating material. the wire harness top is opened, the upper mold is divided into a main pressing and wire-pressing,且
And a resin injection recess is formed in the center of the lower mold.
It is characterized by including a setting step of setting in a mold having a wide open air surface of the injection recess, and a molding step of pouring hot-melted polyamide resin into the mold in which the wire harness is set and cooling and curing at room temperature. There is.

According to a second aspect of the present invention, there is provided a waterproof treatment method for a branch portion of a wire harness branch line according to the first aspect of the present invention, wherein the polyamide resin has a softening point (JIS). K2207) 150 °
C or higher, hardness at room temperature (JIS C hardness tester) 60-1
00, 30~70P _S, water absorption 0 in melt viscosity 190 °.
6% / day or less, insulation resistance at saturated water absorption of 100 M ohm or more, shear strength of 490 to 640 N / _cm ² , molecular weight of 7,000 to 9000, amide bond is about 35% in terms of molecular weight ratio, and wettability is JISK6768. It is characterized in that it has characteristics such that the prescribed test method gives a rate of 48 dyne / cm or more.

According to a third aspect of the present invention, there is provided a waterproofing device for a branch portion of a wire harness branch line, which holds an electric wire in a fixed position and an upper die is divided into a main wire retainer and an electric wire retainer .
In addition, a resin injection recess is formed in the center of the lower mold,
The present invention is characterized by comprising a molding die having a wide atmosphere-opening surface of the oil injection concave portion, a transfer device for moving the molding die to the resin filling portion, and a hot melt dispenser having a nozzle movable in the axial direction of the electric wire. There is.

According to a fourth aspect of the present invention, there is provided a waterproofing device for a branch portion of a wire harness branch line, which holds an electric wire in a fixed position, and an upper die is divided into a main wire retainer and an electric wire retainer ,
In addition, a resin injection recess is formed in the center of the lower mold,
The mold was provided with a mold having a large open air surface of the injection recess, a transfer device for moving this mold to the resin filling part, and a hot melt dispenser having a nozzle having a plurality of holes in the axial direction of the electric wire. It is characterized by that.

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

According to the method of waterproofing a branch portion of a wire harness branch wire according to the present invention as set forth in claim 1, in the connection step, the main wire and the branch wire of the wire harness covered with an insulating coating material are connected, and in the setting step, top wire harness is opened, the upper mold is divided into a main pressing and wire-pressing,且
And a resin injection recess is formed in the center of the lower mold.
The injection recess is set in a mold having a large open air surface , and in the molding step, the hot-melt polyamide resin is poured into the mold in which the wire harness is set and cooled and cured at room temperature. At this time, since the adhesion between the polyamide resin and the insulating coating material of the wire harness is good, it is possible to improve the insulation strength and waterproof performance of the branch portion of the wire harness branch line.

Further, since the upper die is divided into a main wire retainer and an electric wire retainer, and since the molding die has a large open surface to the atmosphere, it is cooled.
When curing, the amount of heat released from the resin surface, which is the surface open to the atmosphere, is large.
In addition, the heat dissipation inside the resin is completed in a short time as with the resin skin.
Finish. As a result, at the time of cooling and hardening, a difference in hardening speed between the resin surface and the inside is small and a negative pressure is not generated in the molding die, so that bubbles are less likely to be generated around the electric wire. For the same reason, internal stress is less likely to remain, and solvent stress cracks are less likely to occur when contacting various oil materials. Further, since there is no special constraint condition on the amount of the material and the amount of the material is easily controlled, the yield of the material is good. Further, since it is an easy processing method, no skill is required and it is easy to automate. Furthermore, the material color of the polyamide resin is dark brown and transparent, and the inside can be seen, so that the quality of the connection shape and the resin mold attachment can be visually confirmed.

According to a second aspect of the present invention, there is provided a waterproof treatment method for a branched portion of a wire harness branch line according to the first aspect of the present invention, wherein the polyamide resin has a softening point of 150 ° C. Above, hardness at room temperature 60
~100, 30~70P _S, water absorption 0.6% / day or less, insulation resistance 100M at saturation water in melt viscosity 190 °
A molecular weight of 7,000 to 9000, a amide bond of about 35% in terms of molecular weight ratio, and a wettability of 48 dyne / cm or more by the test method specified by JISK6768 so that the shear strength is 490 or more and the shear strength is 490 to 640 N / _cm ^2. Since the characteristics are provided, the adhesion between the polyamide resin and the insulating coating material of the wire harness is improved, and the insulation strength and the waterproof performance of the branch portion of the wire harness branch line can be improved.

According to a third aspect of the present invention, there is provided a waterproofing device for a branch portion of a wire harness branch line, which holds an electric wire in a fixed position, and a forming die whose upper die is divided into a main wire retainer and an electric wire retainer. To move to the resin injection part. The hot melt dispenser moves a nozzle in the axial direction of the electric wire, and pours the polyamide resin into the entire region of the mold for resin injection. Therefore, it is possible to efficiently flow the polyamide resin into the resin injection concave portion, and it is possible to significantly improve the productivity. In addition, the equipment configuration is simple, so it is inexpensive. Further, since it is an easy processing method, no skill is required and it is easy to automate. Furthermore, the upper die of the molding die is divided into a main wire retainer and an electric wire retainer, and since the atmosphere of the molding die is wide, the resin surface that becomes the atmosphere open surface at the time of cooling and curing.
There is a large amount of heat radiation from, and the heat radiation inside the resin is also the same as the resin skin
So that it will be completed in a short time. As a result, at the time of cooling and hardening, the difference in hardening speed between the resin surface and the inside of the resin is small, and since negative pressure does not occur in the molding die, bubbles are less likely to be generated around the wire, and internal stress is less likely to remain. Therefore, even when it comes into contact with various oil materials, solvent stress cracks of the product do not easily occur.

According to a fourth aspect of the present invention, there is provided a waterproofing apparatus for a branch portion of a wire harness branch line, which holds an electric wire in a fixed position, and a forming die in which an upper die is divided into a main wire retainer and an electric wire retainer. To move to the resin injection part. In a hot melt dispenser, a polyamide resin is poured into a resin injection recess of a molding die from a nozzle provided with a plurality of holes in the axial direction of an electric wire. Therefore, it is possible to efficiently flow the polyamide resin into the resin injection concave portion, and it is possible to significantly improve the productivity. In addition, the equipment configuration is simple, so it is inexpensive. Further, since it is an easy processing method, no skill is required and it is easy to automate. Further, the upper die of the molding die is divided into a main wire retainer and an electric wire retainer, and since the atmosphere of the molding die is wide, it becomes the atmosphere open surface during cooling and curing.
A large amount of heat is dissipated from the resin surface, and the heat dissipated inside the resin is
It completes in a short time, just like a peel. As a result, at the time of cooling and hardening, the difference in hardening speed between the resin surface and the inside of the resin is small, and since negative pressure does not occur in the molding die, bubbles are less likely to be generated around the wire, and internal stress is less likely to remain. Therefore, even when it comes into contact with various oil materials, solvent stress cracks of the product do not easily occur.

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

Further, when the upper and lower molds are closed, the polyamide resin rises from the window portion, so that even if sink marks occur during cooling and curing, the connecting portion of the electric wire is not exposed. In addition, from the resin surface, which is the surface open to the atmosphere when cooling and hardening by the window
Has a large amount of heat radiation, and the heat radiation inside the resin is similar to that of the resin skin.
It will be completed in a short time. As a result, at the time of cooling and hardening, a difference in hardening speed between the resin surface and the inside is small and a negative pressure is not generated in the molding die, so that bubbles are less likely to be generated around the electric wire.
For the same reason, internal stress is less likely to remain, and solvent stress cracks are less likely to occur when contacting various oil materials.
Further, since there is no special constraint condition on the amount of the material and the amount of the material is easily controlled, the yield of the material is good. Furthermore, since it is an easy processing method, no skill is required and it is easy to automate.

[0032]

[0033]

[0034]

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a waterproofing method for a branch portion of a wire harness branch line according to the present invention will be described with reference to FIGS.

As shown in FIG. 1A, in the wire harness waterproofing method of the first embodiment, the branch wire 16 is connected to the main wire 10 of the wire harness by thermocompression bonding or metal tube caulking in the wire connecting step. In the setting step, the mold is set in the mold 40 having an open upper surface.

As shown in FIG. 4, the main wire 10 and the branch wire 16 of the wire harness are composed of a copper electric wire 14 having a coating 12 made of vinyl chloride.

As shown in FIG. 2, the molding die 40 is made of Teflon (registered trademark of DuPont) resin mixed with a fluorine resin having good water repellency, and is connected to the upper die 44 through a joint 42. It is composed of a lower mold 46.
The lower mold 46 has a wedge-shaped resin injection recess 48 formed in the center thereof, and a groove as a main line holding portion formed on one longitudinal edge 40A of the resin injection recess 48 for setting the wire harness main line. 50 and two grooves 52, 54 as electric wire holding portions, which are formed on the other edge 40B in the longitudinal direction of the resin injecting recess 48 and in which the wire harness main line and the wire harness branch line are set with a predetermined gap therebetween. And are equipped with. In addition, the upper die 44 includes a main line retainer 44A for retaining the wire harness main line with the groove 50, and the grooves 52, 54.
And an electric wire retainer 44B for pressing the wire harness main line and the wire harness branch line with each other. The main wire retainer 44A is provided with a protrusion 56 that enters the groove 50 and contacts the wire harness main line.
The protrusions 58 and 60 that enter the grooves 52 and 54 and contact the wire harness main line and the wire harness branch line are formed in the.

The grooves 50, 52 and 54 are set so that the gap between the electric wires and the gap between the electric wire and the mold are about 1.5 mm, respectively. When used, it is possible to secure the surrounding property of a predetermined resin and the insulation performance of the product.

As shown in FIG. 1B, in the setting step of the waterproofing method for the wire harness of the first embodiment, with the main wire 10 and the branch wire 16 of the wire harness set in the lower mold 46, The main wire retainer 44A and the electric wire retainer 44B are tilted in the direction of the lower mold 46 (direction of arrow A in FIG. 1B) to fix the main line 10 and the branch line 16 of the wire harness.

As shown in FIG. 1C, in the molding step, the nozzle 62A of the hot melt dispenser 62 is placed in the resin injection recess 48 of the molding die 40 to which the main wire 10 and the branch wire 16 of the wire harness are fixed. From 200 ° C to 2
The polyamide resin 22 hot melted at 20 ° C. is poured and cooled and cured at room temperature. The viscosity of the polyamide resin 22 as, for hot melt to 200 ° C~220 ° C was shown in FIG. 10 has a 30P _S weak.

As shown in FIG. 3, the hot melt dispenser 62 comprises a nozzle 62A, a heater 64, a cylinder sleeve 66, a piston 67, and a cassette holder 68, and a tablet-shaped polyamide resin 70 loaded in the cassette holder 68. It is sent to the cylinder sleeve 66 and pushed into the heater 64 by the piston 67. The tablet-shaped polyamide resin 70 is melted by the heater 64, and the nozzle 62A
The molten polyamide resin 22 is discharged into the resin injection recess 48 of the molding die 40.

Also, the hot melt dispenser 62
Is fixed to the arm 72A of the drive device 72, and is moved integrally with the arm 72A by the piston 74, so that the nozzle 62A is set in the molding die 40 in the axial direction of the wire harness main line 10 (see FIG. ) Arrow F
Direction). Therefore, the polyamide resin 22 is made to flow evenly into the resin injection recess 48 of the molding die 40.

Further, the molding die 40 is cooled by the carrying device 82 having the drive motor 76, the gear 78 and the carrying belt 80, and the cooling stage 8 provided downstream of the nozzle 62A.
It is conveyed to No. 4 and cooled here.

When the above-mentioned polyamide resin is poured into the Teflon resin molding die 40 and cooled in the atmosphere at 20 ° C., it takes 40 seconds or more. Therefore, the cooling stage 8
It is preferable that two or more 4 are provided.

As shown in FIG. 4, the product 86 taken out from the mold after cooling and hardening is the main wire 10 of the wire harness.
A polyamide resin 22 covers a connecting portion 20 between the branch wire 16 and the branch wire 16. Further, the polyamide resin 22 of the product 86 has a wedge shape with no unevenness on the surface, so that the water can be immediately cut off even if it is covered with water. Further, the polyamide resin 22 of the product 86 has a wall thickness A of about 1.5 mm all around the electric wire,
The sealing length B of each electric wire is about 5 mm, and the gap C between the electric wires is about 1.5 mm. The outer diameter of the wire is 2 mm.

Further, the product 86, after the temperature and humidity stress is added,
Insulation resistance 100M ohm or more at room temperature, tensile strength 6
0N above, has a sealing pressure 50KP _a more properties.

As shown in FIGS. 5 and 6, the temperature stress and the humidity stress are assumed to be used in an environment where there is a possibility of rainwater in the engine room of the automobile. In addition, the performance standard is a value based on the following evaluation method in consideration of general use conditions of the automobile and durability when the wire harness is assembled to the vehicle body.

As shown in FIG. 7, for insulation resistance, a metal foil 28 is wound around the waterproofing portion 26 of the wire harness 24, and DC 5 is applied between the copper wire 30 and the metal foil 28 of the wire harness 24.
The value is measured with an insulation resistance meter of 00V.

As shown in FIG. 8, the tensile strength is 100 in the axial direction of the electric wire (direction of arrow C in FIG. 8) while fixing one end 24A of the wire harness 24, grasping the waterproofing processing portion 26.
It is pulled at a constant speed of mm / min, and the load is applied when the waterproofing portion 26 is pulled out or peeled from the wire harness 24.

As shown in FIG. 9, the seal pressure is such that compressed air is sent from the copper wire of the wire harness 24 from the air source 34 via the air regulator 32, and air leaks from the waterproof processing portion 26 immersed in the water 36. The air pressure when it is generated.

Further, in order to satisfy each required performance of the product,
As a material of the waterproofing unit 26, a softening point (JIS K2
207) Hardness at room temperature (JIS C
Hardness meter) 60 to 100, melt viscosity at 190 ° C 30 to 7
0P _S (see FIG. 10), water absorption rate 0.6% / day or less (see FIG. 11, measured with a plate having a thickness of 3 mm), insulation resistance at saturated water absorption of 100 ohms or more (see FIG. 12, plate with a thickness of 3 mm) To have a shear strength of 490 to 690 N / cm ² , a molecular weight of 7,000 to 9000, an amide bond is about 35% in a molecular weight ratio, and the distribution of the amide bond in the molecule is unevenly distributed so that the molecule itself has electrical characteristics. Polyamide resin is used.

Next, the operation of the first embodiment will be described. In the waterproof treatment method for the branch portion of the wire harness branch line of the first embodiment, the branch line 16 is connected to the main line 10 of the wire harness in the connecting step, and the molding die 40 having an open upper surface is set in the setting step. set. Next, in the molding step, the hot-melted polyamide resin 22 is poured into the resin injection recess 48 of the molding die 40 in which the wire harness is set, and is cooled and cured at room temperature. At this time, the adhesion between the polyamide resin 22 and the insulation coating material 12 of the wire harness is good, so that the insulation strength and the waterproof performance of the branch portion of the wire harness branch line can be improved.

Further, since the upper die 44 of the molding die 40 is divided into the main line retainer 44A and the wire retainer 44B, the atmosphere open surface of the molding die 40 is wide. Therefore, during cooling and curing
In addition, a large amount of heat is radiated from the resin surface, which is the surface open to the atmosphere,
The heat radiation inside the oil is completed in a short time, just like the resin skin.
It As a result, at the time of cooling and hardening, a difference in hardening speed between the resin surface and the inside of the resin is small and a negative pressure is not generated in the molding die 40, so that bubbles are less likely to be generated around the electric wire. For the same reason, internal stress is less likely to remain, and solvent stress cracks of the product 86 are less likely to occur even when contacting various oil materials.

Further, since there is no special restriction condition on the amount of the polyamide resin 22 and the amount of the polyamide resin 22 can be easily controlled, the yield of the polyamide resin 22 is good. Furthermore, since it is an easy processing method, no skill is required and it is easy to automate.

Further, in the waterproof treatment method for the branch portion of the wire harness branch according to the first embodiment, the polyamide resin 22 used has a softening point of 150 ° C. or higher and a hardness of 60 to 60 at room temperature.
100, 30~70P _S, water absorption 0.6% / day or less, insulation resistance 100M at saturation water in melt viscosity 190 °
A molecular weight of 7,000 to 9000, a amide bond of about 35% in terms of molecular weight ratio, and a wettability of 48 dyne / cm or more by the test method specified by JISK6768 so that the shear strength is 490 or more and the shear strength is 490 to 640 N / _cm ^2. Because of the characteristics, the adhesiveness between the polyamide resin 22 and the insulating coating material 12 of the wire harness is improved, and the insulation strength and waterproof performance of the branch portion of the wire harness branch line can be further improved.

Further, since the material color of the polyamide resin 22 is dark brown and the inside can be seen, it is possible to visually check the quality such as the connection shape and the resin mold attachment condition.

Further, in the waterproofing method of the branch portion of the wire harness branch line according to the first embodiment, since the mold 40 is made of Teflon resin, the polyamide resin 22 is cooled more than the conventional metal mold. The curing speed can be suppressed.
Therefore, at the time of cooling and hardening, a difference in hardening speed between the resin surface and the inside is small and no negative pressure is generated in the molding die, so that bubbles are less likely to be generated around the electric wire. For the same reason, internal stress is less likely to remain, and solvent stress cracks are less likely to occur when contacting various oil materials.

Further, since it is made of Teflon resin having good water repellency, it is not necessary to apply a mold release agent to the molding die. Therefore, it is possible to prevent the insulation strength and the waterproof performance of the branch portion of the wire harness branch line from being deteriorated due to the release agent getting around.

In the hot melt dispenser 62 of the first embodiment, the nozzle 62A is movable in the axial direction of the wire harness main line 10 set in the molding die 40. Therefore, the polyamide resin 22 evenly flows into the resin injection recess 48 of the molding die 40, and the molding die 40
It is possible to efficiently flow the polyamide resin into the resin injection recess 48, and it is possible to significantly improve the productivity. In addition, the equipment configuration is simple, so it is inexpensive. Furthermore, since it is an easy processing method, no skill is required and it is easy to automate.

When the length of the polyamide resin 22 in the axial direction of the electric wire is 25 mm or more, when a single hole nozzle having a shaft diameter of about 1 mm is used, the resin injection recess 4 of the molding die 40 is used.
In order to uniformly fill the polyamide resin 22 in 8, the nozzle 62A requires a moving mechanism that allows the nozzle 62A to move in the axial direction of the wire harness main line 10 set in the molding die 40, but instead of this, As shown in FIG. 13, a nozzle 88 having a plurality of holes 88A formed along the axial direction of the wire harness main line 10 may be used.

Further, in the waterproof treatment method for the branch portion of the wire harness branch line of the first embodiment, since the polyamide resin 22 of the product 86 has a wedge shape without unevenness on the surface, it is difficult for water to collect on the surface of the polyamide resin. It is advantageous for waterproofing.

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

The same members as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

[0070]

[0071]

[0072]

[0073]

[0074]

According to the first aspect of the present invention, there is provided a waterproof treatment method for a branch portion of a wire harness branch line, which comprises a wiring step of connecting a main wire and a branch wire of a wire harness covered with an insulating coating material, and a wire harness. The upper surface is open , the upper die is divided into a main wire retainer and an electric wire retainer , and a tree is placed in the center of the lower die.
The oil injection recess is formed, and the atmosphere opening surface of the resin injection recess
Since it includes a setting step of setting in a wide mold and a molding step of pouring hot-melted polyamide resin into the mold in which the wire harness is set and cooling and curing at room temperature, it is possible to improve insulation strength and waterproof performance. It has an excellent effect that solvent stress cracks of the product hardly occur even when it comes into contact with various oil materials.

According to a second aspect of the present invention, there is provided a waterproof treatment method for a branch portion of a wire harness branch line according to the present invention, which is the same as the waterproof treatment method for a branch portion of the wire harness branch line according to the first aspect, in which the polyamide resin has a softening point (JIS K2207). ) 150 ° C or higher, normal temperature hardness (JIS C hardness meter) 60 to 100,
30~70P _S, water absorption of 0.6% in melt viscosity 190 ° /
day or less, insulation resistance at saturated water absorption of 100 M ohms or more, and shear strength of 490 to 640 N / _cm ² , a molecular weight of 7,000 to 9000, and an amide bond in a molecular weight ratio of about 3
Since the wettability is 5% and the wettability is 48 dyne / cm or more according to the test method defined by JISK6768, the adhesion between the polyamide resin and the insulation coating material of the wire harness is improved, and the wire harness branch line is improved. It has an excellent effect that the insulation strength and the waterproof performance of the branch portion can be improved.

According to a third aspect of the present invention, there is provided a waterproofing device for branching a wire harness branch line, which holds an electric wire in a fixed position and an upper die is divided into a main wire retainer and an electric wire retainer .
In addition, a resin injection recess is formed in the center of the lower mold,
A molding die having a wide atmosphere opening surface of the injection recess, a transfer device for moving this molding die to the resin filling portion, and a hot melt dispenser having a nozzle movable in the axial direction of the electric wire,
Since it is provided, it is possible to efficiently flow the polyamide resin into the resin injection recess, and it is possible to significantly improve the productivity. In addition, the equipment configuration is simple, so it is inexpensive. Also, because of the easy processing method, no skill is required,
Easy to automate. Further, it has an excellent effect that the solvent stress cracks of the product hardly occur even when it comes into contact with various oil materials.

According to a fourth aspect of the present invention, there is provided a waterproofing device for a branch portion of a wire harness branch line, which holds an electric wire in a fixed position and an upper die is divided into a main wire retainer and an electric wire retainer .
In addition, a resin injection recess is formed in the center of the lower mold,
Since a mold having a wide open air surface of the injection recess, a conveying device for moving the mold to the resin filling section, and a hot melt dispenser having a nozzle having a plurality of holes in the axial direction of the electric wire are provided. It is possible to efficiently flow the polyamide resin into the resin injecting recess, and it is possible to significantly improve the productivity. In addition, the equipment configuration is simple, so it is inexpensive. Further, since it is an easy processing method, no skill is required and it is easy to automate. Further, it has an excellent effect that the solvent stress cracks of the product hardly occur even when it comes into contact with various oil materials.

[0078]

[0079]

[0080]

[0081]

[0082]

[0083]

[0084]

[0085]

[Brief description of drawings]

1A to 1C are explanatory views showing a waterproof treatment method for a wire harness branch line branch portion according to a first embodiment of the present invention.

FIG. 2 is a three-sided view showing a molding die of the waterproof processing apparatus for the wire harness branch line branching portion according to the first embodiment of the present invention.

FIG. 3 is a schematic view showing a waterproof processing device for a branch portion of a wire harness branch line according to the first embodiment of the present invention.

FIG. 4 is a three-sided view showing a product manufactured by the waterproofing method for the branch portion of the wire harness branch line according to the first embodiment of the present invention.

FIG. 5 is a graph showing temperature stress of a product manufactured by the waterproof treatment method for the wire harness branch portion according to the first embodiment of the present invention.

FIG. 6 is a graph showing humidity stress of a product manufactured by the waterproofing method for the branch portion of the wire harness branch according to the first embodiment of the present invention.

FIG. 7 is an explanatory diagram of an insulation resistance measuring method.

FIG. 8 is an explanatory diagram of a tensile strength measuring method.

FIG. 9 is an explanatory diagram of a seal pressure measuring method.

FIG. 10 is a graph showing melt viscosity of polyamide resin.

FIG. 11 is a graph showing the water absorption rate of a polyamide resin.

FIG. 12 is a graph showing a relationship between a water absorption rate of a polyamide resin and an insulation resistance value.

FIG. 13 is a perspective view showing another example of the nozzle of the waterproof processing device for the wire harness branch line branch portion according to the first example of the present invention.

FIG. 14 is a view for preventing a branch portion of a wire harness branch line according to a conventional example .
It is a perspective view showing a water treatment method.

[Explanation of symbols]

10 Main wire harness 12 coating 16 branches 20 connection 22 Polyamide resin 40 Mold 42 joint 44 Upper mold 44A Main line press 44B wire retainer 46 Lower mold 48 Resin injection recess 50 grooves (main line holding part) 52 groove (electric wire holding part) 54 groove (electric wire holding part) 62 hot melt dispenser 62A nozzle 72 Drive 84 Cooling stage 86 products 88 nozzles 88A hole

Continuation of front page (56) Reference JP-A-5-260624 (JP, A) JP-A-4-223110 (JP, A) JP-A-4-154502 (JP, A) JP-A-7-245864 (JP , A) JP 58-10385 (JP, A) JP 3-280374 (JP, A) JP 60-105185 (JP, A) JP 61-243683 (JP, A) JP 7-264743 (JP, A) JP 7-94253 (JP, A) JP 61-66141 (JP, A) JP 63-314840 (JP, A) JP 6-93098 (JP, A) Actual development Sho 60-153491 (JP, U) Actual development Sho 58-903 (JP, U) Japanese Patent Publication 4-47433 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) ) H01R 43/00 H01R 4/70 H02G 1/14

Claims (4)

(57) [Claims] 1. A connecting step of connecting a main wire and a branch wire of a wire harness covered with an insulating coating material, an upper surface of the wire harness is opened, and an upper die is divided into a main wire retainer and an electric wire retainer , and A resin injection recess is formed in the center of the lower mold.
And a molding step in which a hot-melt polyamide resin is poured into the molding die in which the wire harness is set, and is cooled and cured at room temperature. A waterproof treatment method for a branch portion of a wire harness branch line, comprising: 2. The softening point (JIS
K2207) Hardness at room temperature (JIS)
C hardness meter) 60 to 100, melt viscosity 30 at 190 °
～70P _S, water absorption 0.6% / day or less, when the saturated water absorption insulation resistance 100M Ohm or more, the shear strength 490-64
As will be 0N / _cm ^2, molecular weight 7000 to 9000,
The amide bond is about 35% in terms of molecular weight, and the wettability is JIS
2. The waterproof treatment method for a branch portion of a wire harness branch line according to claim 1, wherein the test method defined by K6768 is provided with a property of 48 dyne / cm or more. 3. The electric wire is held in place, the upper die is divided into a main wire retainer and an electric wire retainer , and the center of the lower die.
The resin injection recess is formed in the
A wire harness branch line comprising: a mold having a wide air opening surface, a conveying device for moving the mold to the resin filling portion, and a hot melt dispenser having a nozzle movable in the axial direction of the electric wire. Waterproofing device for branching. 4. The electric wire is held in place, the upper die is divided into a main wire retainer and an electric wire retainer , and the center of the lower die.
The resin injection recess is formed in the
And a hot melt dispenser having a nozzle provided with a plurality of holes in the axial direction of the electric wire. A waterproofing device for the branch part of the wire harness.