JPH0536448A - Water proofing method and waterproofing structure for terminal connecting part of covered cable - Google Patents

Abstract

PURPOSE:To prevent the penetration of water from each clearance and prevent the deterioration of a part to be connected by receiving a sol filler in a terminal protecting cap, press-fitting the terminal part of a coated cable into the internal space, and conducting heating and hardening to connect the terminal part. CONSTITUTION:A sol filler 60 consisting of a resin material is received in a terminal protecting cap 40 of a fat molded product. The terminal part of a coated cable is press-fitted to the internal space 41 of the cap 40, and the filler 60 is penetrated into a clearance E1 between conductors 31 of the cable and respective clearances E2, E3 among the conductors 31, insulating layers 32, and coat layers 34. The coat layers 34, the cap 40 and the filler 60 are hardened in this state by heating and connected. Each of clearances E1, E2, E3 is blocked by the filler 60, the penetration of water into the terminal connecting part is prevented, and the corrosion of a temperature sensor can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproofing method and a waterproofing structure for a terminal connecting portion of a covered electric wire used for a sensor cord or the like.

[0002]

2. Description of the Related Art A sensor cord provided with a temperature sensor is used for various devices such as a water temperature detecting device, an underground temperature detecting device, a freezer showcase, and a refrigerator internal temperature detecting device. The (temperature detection part) is waterproofed.

FIG. 9 shows a waterproof structure of a terminal connecting portion of a conventional covered electric wire used for a sensor cord (Japanese Patent Laid-Open No. 2-4612).
FIG. 1 is a cross-sectional view showing No. 1). As shown in the figure, the covered electric wire 1 includes an insulated electric wire 4 in which an insulating layer 3 is provided on the outer periphery of two stranded conductors 2, and a covering layer 5 covering the two insulated electric wires 4. And have. At the end portion of the covered electric wire 1, the covering layer 5 and the insulating layer 3 are removed and the conductor 2
Is exposed. The lead wire 11 on one side of the temperature sensor 10 is connected to the conductor 2 on one side, and
The lead wire 11 on the other side of the temperature sensor 10 is connected to the conductor 2 on the other side.

Further, the terminal portion of the covered electric wire 1 is a terminal protection material 6
By molding. At this time, the terminal protection material 6 is made of the same material as the coating layer 5 (for example, vinyl chloride resin, polyethylene resin, etc.), and both materials 5, 6 are melted by heat treatment and then cooled and cured to both materials 5, 5. Combine 6 Thus, the temperature sensor 10 and the lead wire 1
1 is sealed with a terminal protection material 6 to improve the waterproof performance.

On the other hand, in another conventional waterproof structure of a terminal connecting portion of a covered electric wire shown in FIG. 10, a thermosetting resin (eg, epoxy resin, silicone resin, etc.) is provided in a terminal protection cap 20 formed of a metal pipe or the like. ) Etc.
Is stored and the end portion of the covered electric wire 1 is inserted. Then, in that state, the filling material 21 is heated and hardened to seal the temperature sensor 10 and the lead wire 11.

When using a sensor cord having such a waterproof structure of the terminal connecting portion of the covered electric wire, the other end (not shown) of the covered electric wire 1 is connected to the apparatus main body, and the terminal connecting portion is grounded. Or install in water. At this time, since the temperature sensor 10 and the like are sealed by the terminal protection material 6, or the filling material 21 and the terminal protection cap 20, it is possible to prevent water from entering the terminal connection portion around the temperature sensor 10 from the outside. Each has a sufficient waterproof effect.

[0007]

However, in the conventional waterproof structure of the terminal connecting portion of the covered electric wire, since the viscosity of the terminal protection material 6 or the filler 21 when melted is relatively high, the terminal protection material 6 or the filler material. 21 does not enter the gaps between the conductor 2, the insulating layer 3, and the coating layer 5.

For this reason, when the apparatus main body is placed outdoors, moisture such as rainwater enters the inside of the covered electric wire 1 from the connection portion between the covered electric wire 1 and the apparatus main body, and the water content is caused by the capillary phenomenon to cause the conductor. 2, through the gaps between the insulating layer 3 and the coating layer 5 to enter the peripheral portion (terminal connection portion) of the temperature sensor 10. Therefore, there arises a problem that the lead wire 11 of the temperature sensor 10 and the sensor body are corroded by moisture.

A first object of the present invention is to solve the above-mentioned problems of the prior art, to prevent water from entering the terminal connecting portion through the gaps between the conductor of the coated electric wire, the insulating layer and the coating layer, and to provide a temperature sensor or the like. Another object of the present invention is to provide a method for waterproofing a terminal connecting portion of a covered electric wire, which can prevent deterioration of the connected component.

A second object of the present invention is to solve the above-mentioned problems of the prior art, prevent moisture from entering the terminal connecting portion through the gaps between the conductor of the coated electric wire, the insulating layer and the coating layer, and temperature sensor etc. Another object of the present invention is to provide a waterproof structure for the terminal connecting portion of the covered electric wire, which can prevent deterioration of the connected parts.

[0011]

In order to achieve the above first object, a method for waterproofing a terminal connecting portion of a covered electric wire according to claim 1 is such that an insulated electric wire provided with an insulating layer on a conductor is covered with a resin coating layer. And a step of preparing a covered electric wire covered with the above, and the terminal protection cap made of a molded product of the same kind of material as the covering layer while the opening size of the internal space is formed to be approximately the same as the outer diameter of the covered electric wire. And a step of removing the insulating layer and the coating layer at the end portion of the covered electric wire to expose the conductor, and attaching a connected component to the exposed conductor portion, and a sol made of the same material as the resin material. The filler to be connected is accommodated in the internal space of the terminal protection cap in a state of being accommodated in the internal space of the terminal protection cap, and the coating layer in the terminal portion of the covered electric wire is provided in By press-fitting in the space, and the insertion pressure by the said sol fillers conductor, the step of entering the respective gaps of the insulating layer and the covering layer, the covering layer,
Curing the terminal protection cap and the filler by heat treatment to bond them together.

In order to achieve the second object, the second aspect
The waterproof structure of the terminal connection portion of the covered electric wire according to claim 1, the insulated electric wire provided with an insulating layer on the conductor is covered with a resin coating layer, and the covered electric wire in which the conductor is exposed at the terminal portion, and the exposed conductor A connected connected component and a molded product of the same material as that of the coating layer, the connected component is housed in its own internal space, and the end portion of the coated electric wire is provided at the peripheral edge of the opening of the internal space. And a gap between the cover layer, the insulating layer, and the conductor, which is made of the same material as the cover layer and the end protection cap and is filled in the inner space. And a filling material that is hardened in a state of penetrating.

[0013]

According to the method of waterproofing a terminal connection portion of a covered electric wire according to claim 1, a sol-like filler is contained in the terminal protection cap, and the coating layer at the terminal portion of the covered electric wire is provided inside the terminal protection cap. It is pressed into the space and the insertion pressure causes the sol-like filler to enter the gaps between the conductor, insulating layer and coating layer of the coated wire, and in that state the coating layer, terminal protection cap and filler are cured by heat treatment. Since they are joined together, the gaps are closed by the filler.

In the waterproof structure of the terminal connecting portion of the covered electric wire according to the second aspect, since the filler is invaded into each gap between the conductor, the insulating layer and the cover layer of the covered electric wire, the gap is blocked by the filler. To be done.

[0015]

1 is a sectional view showing a waterproof structure of a terminal connecting portion of a covered electric wire to which a waterproofing method according to an embodiment of the present invention is applied.

As shown in the figure, the waterproof structure of the terminal connecting portion is applied to one end of the sensor cord S,
It has a covered electric wire 30, a terminal protection cap 40, a connected component such as a temperature sensor 50, and a filler 60 filled in the protection cap 40.

To form the waterproof structure of the terminal connecting portion, first, as shown in FIGS. 2 and 3, the covered electric wire 30 and the terminal protection cap 40 are prepared.

The covered electric wire 30 includes two insulated electric wires 33,
And a coating layer 34 that covers them. Among them, the insulated electric wire 33 is formed by twisting a plurality of linear conductors 31 as shown in the enlarged sectional view of FIG.
An insulating layer 32 is formed on the outer periphery of the. In this case, a gap E1 is formed between the conductors 31 and the conductors 31
A gap E2 is formed between the insulating layer 32 and the insulating layer 32. In order to facilitate understanding, the gaps E1 and E2 are shown in FIG.
Is drawn wider than it actually is.

Then, as shown in FIG. 2, the two twisted insulated wires 33 are extrusion-coated with a molding material containing vinyl chloride resin of porous particles as a main component and a plasticizer and a stabilizer mixed therein. To form a coating layer 34, and thus the coated electric wire 3 having a diameter (outer diameter dimension) h1 of about 5.0 mm.
Form 0. In this case, in the covered electric wire 30, as shown in the enlarged cross-sectional view of FIG. 5, a gap E3 is formed between the insulating layer 32 and the covering layer 34 (the gap E3 is also drawn wide in FIG. 5). ).

On the other hand, as shown in FIG. 3, the terminal protection cap 40 is obtained by molding using a vinyl chloride resin or the like which is the same material as the molding material of the coating layer 34,
The depth h2 is about 30 mm, and the opening 42 has an inner space 41 finished to about 5.0 mm, which is the same as the outer diameter dimension h1 of the covered electric wire 30.

Then, as shown in FIG.
At the end of the, the coating layer 34 is removed in a small amount and the insulating layer 32 is also removed in a small amount, so that the conductor 31 is covered
Expose a few mm from the 0 terminal.

Next, as shown in FIG. 6, the lead wire 51 on one side of the temperature sensor 50 is soldered and pressure-bonded to the conductor 31 on one side of the conductor 31 exposed from the end portion of the covered electric wire 30. Alternatively, the connection is performed by welding or the like, and the lead wire 51 on the other side is connected to the conductor 31 on the other side by the same process as described above.

Next, as shown in FIG. 7, a sol (paste) filler containing spherical particles of vinyl chloride resin as a main component and a plasticizer and a stabilizer mixed in the inner space 41 of the terminal protection cap 40. 0.45 to 0.50 cc of 60 is injected.

Next, the terminal connecting portion such as the temperature sensor 50 is housed in the internal space 41, and the covered electric wire 30 (the covering layer 34) is further so that the terminal portion of the covering layer 34 is immersed in the filling material 60. The terminal part of is pushed into the internal space 41. In this case, as shown in FIG. 8, since the outer diameter dimension h1 of the covered electric wire 30 and the dimension h3 of the opening 42 of the terminal protection cap 40 are finished to the same dimension, a large insertion pressure is obtained, and the insertion pressure causes the sol. The filling material 60 has a gap E1 between the conductors 31 and the gaps E between the insulating layer 32 and the coating layer 34.
2, invades E3. Moreover, the sol-like filler 60 used in this example has a viscosity at room temperature of about 1000 cPs.
Low (centipoise) and the above gaps E1, E2, E3
Penetrates smoothly into the inside of.

Next, using a high temperature tank such as a gear oven,
After performing a heat treatment at 0 ° C. for 10 minutes, the coating layer 34, the terminal protection cap 40, and the filler 60 are once melted and then cured by cooling to near room temperature. At this time, the gap E1 between the conductors 31 of the covered electric wire 30, and the conductor 31,
Since the filler 60 invading the gaps E2, E3 between the insulating layer 32 and the coating layer 34 is simultaneously cured, the gaps E1, E2, E3 are closed and the coating layer 3 is formed.
4, the terminal protection cap 40 and the filling material 60 are integrally combined. In this case, since the coating layer 34, the terminal protection cap 40, and the filling material 60 are made of the same material, good bonding performance can be obtained.

When using the sensor cord S having the waterproof structure of the terminal connecting portion, the other end side (not shown) of the covered electric wire 30 is connected to the main body of the apparatus, and the terminal connecting portion (temperature sensor 50 portion) is used underwater. Install in the ground. At this time, moisture such as rainwater that has entered the inside of the covered electric wire 30 from the connection portion between the apparatus main body and the covered electric wire 30 has a gap E1 between the conductors 31 of the covered electric wire 30 due to a capillary phenomenon, and the conductor 31, the insulating layer 32, and the like. Even if an attempt is made to enter the terminal connecting portion through the gaps E2, E3 of the coating layer 34, the gaps E1, E
Since 2 and E3 are blocked by the filling material 60, moisture does not enter the inside of the terminal connection portion. Therefore, corrosion of the lead wire 51 of the temperature sensor 50 and the sensor body is prevented.

The coating layer 34 and the terminal protection cap 40
Since the filling material 60 and the filling material 60 are made of the same material and are melt-bonded to each other by the heat treatment, they are integrated and it is possible to reliably prevent the intrusion of moisture from the outside into the terminal connection portion.

[0028]

As described above, according to the waterproof treatment method for the terminal connecting portion of the covered electric wire according to the first aspect, the sol-like filler is housed in the terminal protection cap, so that the terminal portion of the covered electric wire is protected. It is pressed into the inner space of the terminal protection cap, and the insertion pressure causes the sol-like filler to enter the gaps between the conductor, insulating layer, and coating layer of the covered electric wire, and in that state, the coating layer, terminal protection cap, and filler are placed. Since each of the gaps is closed by the filler because it is hardened by heat treatment to be bonded, it is possible to prevent water from entering the terminal connection portion through the gaps and prevent deterioration of connected parts. The effect is obtained.

According to the waterproof structure of the terminal connecting portion of the covered electric wire according to the second aspect, since the filler is invaded into each gap between the conductor, the insulating layer and the covering layer of the covered electric wire, the gap is filled with the filler. Since the water is prevented from entering the terminal connection portion due to the blockage, it is possible to obtain the effect of preventing deterioration of connected parts.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a waterproof structure of a terminal connecting portion of a covered electric wire according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining a manufacturing process of the waterproof structure of the above-described embodiment.

FIG. 3 is a drawing for explaining the manufacturing process of the waterproof structure of the above-mentioned embodiment.

FIG. 4 is a cross-sectional view showing an insulated electric wire applied to the one embodiment.

FIG. 5 is a cross-sectional view showing a covered electric wire applied to the one embodiment.

FIG. 6 is a drawing for explaining the manufacturing process of the waterproof structure of the above-mentioned embodiment.

FIG. 7 is a drawing for explaining the manufacturing process of the waterproof structure of the above-mentioned embodiment.

FIG. 8 is a drawing for explaining the manufacturing process of the waterproof structure of the above-mentioned embodiment.

FIG. 9 is a cross-sectional view showing a waterproof structure of a terminal connecting portion of a conventional covered electric wire.

FIG. 10 is a cross-sectional view showing a waterproof structure of a terminal connecting portion of another conventional covered electric wire.

[Explanation of symbols]

30 covered electric wire 31 conductor 32 insulating layer 33 insulated wire 34 coating layer 40 Terminal protection cap 41 Internal space 42 opening 50 temperature sensor 60 filler E1, E2, E3 clearance

Claims (2)

[Claims] 1. A step of preparing a covered electric wire in which an insulated electric wire having an insulating layer provided on a conductor is covered with a resin coating layer, and an opening size of an internal space is formed to be substantially the same as an outer diameter size of the covered electric wire. In addition, the step of preparing a terminal protection cap made of a molded product of the same material as the coating layer, and the conductor is exposed by removing the insulating layer and the coating layer in the terminal portion of the coated electric wire, the conductor exposed A step of attaching the connected component to the part, and the sol-like filler made of the same kind of material as the resin layer is accommodated in the internal space of the terminal protection cap while accommodating the connected component in the internal space, and The coating layer in the terminal portion of the coated electric wire is press-fitted into the internal space of the terminal protection cap, and the sol-like filler is applied to the conductor, the insulating layer, and the coating layer by the insertion pressure. A method of waterproofing a terminal connecting portion of a coated electric wire, comprising: a step of intruding into a gap; and a step of curing the coating layer, the terminal protection cap, and the filler by heat treatment to bond them to each other. 2. An insulated wire in which an insulating layer is provided on a conductor is covered with a resin coating layer to expose the conductor at a terminal portion, and a connected component connected to the exposed conductor, The cover layer is made of a molded product of the same material, and the connected component is housed in its own internal space, and the cover layer at the end portion of the covered electric wire is fitted to the peripheral edge of the opening of the internal space. And a terminal protection cap, which is made of the same material as the covering layer and the terminal protecting cap, is filled in the internal space, and is hardened while penetrating into the gaps between the covering layer, the insulating layer, and the conductor. Waterproof structure of the terminal connection part of the covered electric wire with the filling material.