JPH03225A - Extrusion cross-head - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an extrusion crosshead, and more particularly to an extrusion crosshead in which a single cord is uniformly coated with a rubber material to improve cord quality characteristics. It is.

[Conventional technology]

Conventionally, a crosshead in an extruder for coating a rubber material on a single cord used as a component of a belt reinforcing layer, etc., has a die 2 on the cord extrusion side of the head body 1, as shown in FIG. An insertion guide 3 for the single cord W is provided on the side opposite to the installation, and a rubber material G is placed in a predetermined position on the side of the head body 1, that is, at a position orthogonal to the extrusion direction of the single cord W. Rubber material G that is press-fitted by pressure
An insertion port 4 is provided on the opposite side thereof, and a discharge port 5 for discharging the rubber material G when the head internal pressure becomes abnormal.

In addition, as another conventional example of the crosshead, there is
As disclosed in Japanese Patent No. 3656, a nipple is inserted into the head body, and a single cord W is inserted into the nipple.
While inserting the rubber material G at a predetermined pressure from the rubber material insertion port provided at a position perpendicular to the extrusion direction of the single cord W.
A crosshead has also been proposed in which a single cord is covered with a rubber material by press-fitting it.

[Problems to be Solved by the Invention] However, in the conventional crosshead as described above, the single cord W is not protected from the pressing force of the rubber material G, or even if it is protected by a nipple or the like. , because a predetermined gap is formed between the die and the tip of the nipple,
There is a problem in that the pressing force of the rubber material G causes the single cord W to curve as shown in Figure 6, making it impossible to provide uniform rubber extrusion coating.
If the cord is pulled, it is not only impossible to maintain the quality characteristics such as the thickness and elongation of the cord, but also there are problems such as cord breakage due to so-called twisting.

[Purpose of the invention]

This invention was devised by paying attention to such conventional problems, and it coats a single cord with a rubber material uniformly, and also improves the quality characteristics of the cord, especially the number of twists.

The object of the present invention is to provide an extrusion crosshead that enables extrusion coating of rubber materials without affecting the thickness, elongation, etc.

[Means to solve the problem]

In order to achieve the above object, this invention forms at least three or more rubber extrusion grooves on the circumference on the die side of the breaker guide, and makes the breaker guide come into contact with the inner wall surface of the head body in a state aligned with the center of the die. integrally forming a breaker head and moving the breaker guide relative to the holder II
The gist of this is that it has been installed in a flexible manner.

[Action of the invention]

The present invention is constructed as described above, and has a guide hole formed in the breaker guide through which the cord is inserted, and is configured so that the rubber material and the cord come into contact for the first time in the vicinity of the die. While preventing deformation due to pressure, it is possible to always provide a uniform rubber coating.

[Embodiments of the invention]

Hereinafter, the present invention will be described in detail based on the accompanying drawings.

FIG. 1 shows a schematic cross-sectional view of an extrusion crosshead embodying the present invention, in which 10 is a crosshead main body, 11 is a die detachably attached to the tip side of the head main body 10, and 12
indicates a holder attached to the rear end side of the head body 10 facing the die 11, and the head body 10 is attached to the side of the head body 10, that is, the single cord W
At a position orthogonal to the extrusion direction, there is an insertion port 13 for the rubber material G into which the rubber material G is press-fitted under a predetermined pressure, and on the opposite side there is an insertion port 13 through which the rubber material G is discharged when the internal pressure of the head becomes abnormal. A discharge port 14 is formed.

Inside the head body 10 are a die 11 and a holder 12.
A breaker guide 15 is housed between the breaker guide 15 and the breaker guide 15, as shown in FIG. 1 and FIGS. , the head body 1 is disposed on the tip side, that is, on the die 11 side.
An umbrella-shaped breaker head 17 is integrally formed on the inner wall surface of 0 so as to be in contact with the die center 0-0.

As shown in FIGS. 3 to 5, this breaker blade 17 has rubber extrusion grooves (1 day) in at least three places on the circumference.
In this embodiment, four breaker heads 17 are formed at 90° intervals, and the breaker heads 17 are connected to the head main body 10 at 90° intervals.
A protruding portion 19 that comes into surface contact with the inner wall surface of the rubber extrusion groove 18 is formed between the protruding portion 19 and the concave rubber extrusion groove 18.
The rubber extrusion groove 18 is formed so that the rubber material G and the cord W come into contact with each other for the first time in the vicinity of the die.

Also, the rear end side of the breaker guide 15, that is, the holder 12
A threaded part 21 is formed on the side to be screwed into a threaded hole 20 formed in the holder 12. By threading the threaded part 21 of the breaker guide 15 into the threaded hole 20 and rotating it, the head body 10 The position of the breaker head 17 that comes into surface contact with the inner wall surface of the breaker head 17 can be adjusted.

That is, by adjusting the position of the breaker head 17, the head pressure, that is, the inner wall surface of the head body 10 and the rubber extrusion groove 1 can be adjusted.
By adjusting the rubber pressure due to the radial gap with
can be adjusted.

Next, to explain the operation of the present invention, after adjusting the breaker head 17 set in the head body 10 so that the head pressure becomes a predetermined pressure, insert the single cord W into the guide hole 16 from the holder 12. On the other hand, rubber material G
Rubber material G at a predetermined pressure is inserted into the head body 10 from the insertion port 13 of the head body 10.
Press fit inside. The rubber material W press-fitted into the head body 10 flows in the direction of the arrow in FIG. By coming into contact with the surface in a wrapping manner and pulling out the single cord W, the rubber material W is coated with a predetermined thickness.

The thickness of the rubber material W to be coated can be adjusted by adjusting the head pressure by adjusting the position of the breaker head 17 as described above. The difference will be adjusted automatically.

By performing the above operations, it is possible to uniformly coat the single cord W with the rubber material G to an arbitrary thickness without deforming it.

〔Effect of the invention〕

In this invention, as described above, on the die side of the breaker guide,
At least three rubber extrusion grooves are formed on the circumference, and a breaker head is integrally formed to abut against the inner wall surface of the head body in alignment with the center of the die, and the breaker guide is attached to the holder. Since the cord is installed so that it can be moved and adjusted, the rubber material can be coated uniformly on a single cord, and the rubber material can be extruded and coated without affecting the quality characteristics of the cord, especially the number of twists, thickness, elongation, etc. Furthermore, since the head pressure can be arbitrarily adjusted, the thickness of the covering rubber material can be easily adjusted.

[Brief explanation of drawings]

Fig. 1 is a sectional view of an extrusion crosshead embodying the present invention, Fig. 2 is a sectional view of the head body, Fig. 3 is a front view of the breaker guide, and Fig. 4 is a side view taken along the line IV-IV in Fig. 3. figure,
FIG. 5 is a sectional view of a breaker guide, and FIG. 6 is a sectional view of a throat to a conventional extrusion cloth. 10...Cross head main body, 11...Head main body,
12... Holder, 13... Insertion port, 14... Outlet port, 15... Breaker guide, 16... Guide hole, 17... Breaker head, W... Single cord, G.
...Rubber material, O-O...Die center. Figure 1 Figure 2

Claims (1)

[Claims] A die is removably attached to the tip side of the head body, and a holder is provided at the rear end side, and a cord is inserted from the holder side into the breaker guide housed between the die and the holder in the head body. In the extrusion crosshead configured to cover the rubber material press-fitted from the side of the breaker guide, at least three rubber extrusion grooves are formed on the circumference on the die side of the breaker guide, and at least three rubber extrusion grooves are formed on the inner wall surface of the head body. 1. An extrusion crosshead, characterized in that a breaker head is integrally formed and brought into contact with the center of the die, and the breaker guide is attached to a holder so as to be movable and adjustable.