JPH0142315Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a mold used when forming a connection portion of a CV cable by an extrusion molding method.

[Conventional technology and its problems] [Part 1] In Fig. 5, 10 is the entire CV cable,
12 is a conductor connection part, and 14 is a cable insulator.

Reference numeral 16 denotes a mold body, into which resin 20 is press-fitted through an injection port 18.

The mold body 16 is provided with several radial exhaust holes 22 at appropriate intervals at both ends. When the injection port 18 is located at the center of the mold body 16, the resin 20 reaches both ends of the mold body 16 at the latest. Therefore, the exhaust holes 22 are provided at both ends of the mold body 16.

As the resin 20 spreads within the mold body 16, gas is exhausted from the exhaust hole 22.

・Problem: For some reason, the inside of one of the exhaust holes 22
It may be blocked by the resin 20. Then, when the gas 24 is sealed in from there and it does not communicate with other exhaust holes 22,
Since the gas 24 has no escape, it remains until the end. Therefore, it becomes impossible to completely fill the resin 20.

[Part 2] As shown in FIG. 6, a breathable tape 26, such as cotton tape, is wrapped between both ends of the mold body 16 and the cable 10. Then exhaust the air through this.

In this case, the tape 26 is in contact with the cable 10, and this is also the location where gas is most likely to accumulate, so if the tape 26 has sufficient ventilation, problems like the above [Part 1] will not occur. However, the problem is that too much tension is applied when wrapping the tape 26,
Alternatively, the air permeability of the tape 26 may deteriorate due to thermal expansion of the tape 14.

If this happens, exhaustion will still be insufficient and complete filling of the resin 20 cannot be expected.

[Means for Solving the Problems] This invention attempts to solve the above problems by using a special exhaust block 28 as shown in FIGS. 1 to 4.

[Embodiment 1] (FIGS. 1 and 2) First, the exhaust block 28 will be explained. The exhaust block 28 has a cylindrical shape as a whole. Because it is attached and detached, it is split in half or more. Also, for example, the inner cylinder 3
It has a two-layer structure of 0 and an outer cylinder 32. In addition,
If necessary, it may be separated into three or more layers.

An exhaust passage 34 is provided between the layers of the inner cylinder 30 and the outer cylinder 32.
form. This leads from the inner end face of the exhaust block 28 to the outer end face. In this case, the outer cylinder 32
A thin axial groove provided on the inner surface of the exhaust passage 34
It consists of

This exhaust block 28 is installed between the inner surface of both ends of the mold body 16 and the cable 10.

An end stopper 42 is attached to the outside thereof. The end stopper 42 is provided with a ring-shaped hole 44 communicating with each exhaust passage 34 and an exhaust hole 46 communicating from the hole 44 to the outside.

[The function] (1) The gas in the mold body 16 is exhausted through the exhaust passage 34 → hole 44 → exhaust hole 46.

(2) Since the exhaust passages 34 are located at both ends inside the mold body 16 and are very close to the cable 10, complete exhaust can be achieved.

(3) Note that as long as the cross-sectional area of the exhaust passage 34 is 2 mm ² or less, there is no problem with the sealing performance of the resin 20.

Further, it has been confirmed that if the number of exhaust passages 34 is six or more, there is no problem in filling the resin 20.

(4) Finish the extrusion molding of the resin 20, and mold body 1
6 is removed, the exhaust block 28 is also removed, the inner cylinder 30 and the outer cylinder 32 are separated, and the resin 20 clogged in the exhaust passage 34 is removed.

The reason why the exhaust block 28 can be separated into at least two layers is to remove the resin 20 stuck in the exhaust passage 34.

If the exhaust block 28 is made into one block and an axial hole is passed through it, the exhaust passage 34
Assuming that, since the exhaust passage 34 is thin as described above, the resin 20 that has entered it
becomes very difficult to remove.

[Example 2] (Figs. 3 and 4) At the joint between the inner cylinder 30 and the outer cylinder 32 on the inside of the exhaust block 28 (the side facing the inside of the mold body 16), a continuous cylinder is provided in the circumferential direction. A gap 36 is formed. Further, a circular hole 38 is formed in the center and communicated with the gap 36. Several holes 40 are provided leading from the hole 38 to the outside. The above gaps 36, holes 38, and holes 40 constitute an exhaust passage 34.

The rest is the same as in the case of [Example 1] above.

[The effect] (1) The gas inside the mold body 16 flows from the gap 36 to the hole 38.
→ hole 40 → hole 44 → exhaust through exhaust hole 46.

(2) In this case, since the side of the exhaust passage 34 facing the inner surface of the mold body 16 is continuous in the circumferential direction, there is no possibility that gas is trapped at the end of the inner surface of the mold body 16. .

[Effects of the invention] (1) Exhaust passage 34 leading from the inner end face to the outer end face
Since the exhaust block 28 formed in the form of is interposed between both ends of the mold body 16 and the cable 10, the inside of the mold body 16 can be easily exhausted and can be completely filled with the resin 20. .

(2) The exhaust block 28 is separated into two or more layers at least in the radial direction, and the exhaust passage 34 is formed between the layers, so after molding, the exhaust passage 3
It is easy to remove the resin 20 that has entered 4.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the first embodiment of the present invention;
The figure is a front view (view of arrow A) of the exhaust block 28 used therein, FIG. 3 is an explanatory diagram of the second embodiment of the present invention, FIG. 4 is an explanatory diagram of the exhaust block 28 used therein, and FIG. and FIG. 6 is an explanatory diagram of an example different from the prior art. 10...Cable, 14...Cable insulator, 16
...Mold body, 18...Injection port, 20...Resin, 22...
Exhaust hole, 28...Exhaust block, 30...Inner cylinder, 32
...Outer cylinder, 34...Exhaust passage, 36...Gap, 38...
Hole, 40... Hole, 42... End stopper.

Claims (1)

[Scope of claim for utility model registration] When connecting a CV cable, conductor connection part 1
2 and the surrounding cable 10 and used to press fit the resin 20 inside, the mold has a cylindrical shape that is divided into two or more as a whole, and is separated into two or more layers at least in the radial direction. The exhaust block 28 has an exhaust passage 34 that communicates from the inner end surface to the outer end surface between the layers.
A mold for connecting a CV cable, characterized in that the following are interposed between both ends of the mold body 16 and the cable 10.