JPH0261900B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a long glass launch channel used in the field of glass launch channels installed between the sash and glass of automobile doors and other fields. The present invention relates to a method for producing a square rubber extrusion molded product.

(Prior Art) Conventionally, long rubber extrusion molded products (hereinafter simply referred to as molded products) such as glass launch channels are generally made of ethylene-propylene-propylene as shown in FIG.
A raw rubber composition such as a diene rubber composition is extruded in an extrusion process, then the unvulcanized molded product obtained in that process is supplied to a vulcanization process and vulcanized, and finally the vulcanized molded product obtained It is obtained through a series of steps in which the product is cooled in a cooling process.

In the extrusion step, the raw rubber composition is extruded through a die 52 having an opening 51 shaped as shown in FIG. 6 to form an unvulcanized molded product 5 as shown in FIG.
3 is obtained.

In the vulcanization process, the unvulcanized molded product 53
As shown in the figure, a first heating area 5 is placed on a belt conveyor 54 and heated by microwaves or the like.
5, and then passes through a second heating zone (not shown) such as a heated air chamber, during which time the unvulcanized molded article 5
3 is vulcanized.

(Problems to be Solved by the Invention) Since this method is carried out continuously, it is highly productive as a method for obtaining the vulcanized molded product 53, but it has the following problems.

The unvulcanized molded product 53 having the cross-sectional shape shown by the two-dot chain line in FIG. do. Thus obtained vulcanized molded product 5
8 has a cross-sectional shape shown by the solid line in the figure.

That is, so-called "sag" occurs in the vulcanized product 58, in which the fin portion 57 of the vulcanized product 58 hangs downward.

A sagging vulcanized molded product 58 is not desirable in terms of product quality, so the thickness of the support portion 57a that supports the fin portion 57 may be increased,
Improvement measures such as changing the shape of the opening 51 of the die 51 in anticipation of sag have also been attempted, but the former method may not meet quality standards, and the latter method
In No. 2, there is a problem in that the distance between the extrusion openings of the two fins 57 becomes narrow, and the strength of the die decreases.

In particular, considering the productivity of the vulcanized molded product 58, the first
As shown in Figure 0, two unvulcanized molded products 58a, 5
8b using one die (not shown) and vulcanize them, the vulcanized product 5 on the right
The degrees of sagging of the right fin portion 59a and the left fin portion 59b of the vulcanized product 8a and the left vulcanized product 58b are different, and there is a limit to the applicability of the above-mentioned improvement means.

Therefore, the object of the present invention is to provide a method for manufacturing a rubber extrusion molded product that can solve these problems.

Structure of the Invention (Means for Solving the Problems) The present invention is designed so that the cross section of the unvulcanized molded product obtained in the extrusion process maintains almost the same shape as the shape immediately after extrusion even after vulcanization. After deforming so that the width of the cross section becomes relatively narrow, the unvulcanized molded product is supplied to a vulcanization process to be vulcanized, and the shape of the cross section of the vulcanized molded product is maintained. This method is intended to solve the above-mentioned problems.

(Function) When an unvulcanized molded product is supplied to the vulcanization process, its cross section is deformed by the heat of the vulcanization process. However, in anticipation of this deformation, the cross-sectional shape of the unvulcanized molded product is forcibly deformed in the opposite way to the above deformation, that is,
The cross-sectional shape of the vulcanized molded product obtained after vulcanization is the same as that of the unvulcanized molded product immediately after extrusion because the unvulcanized molded product is deformed so that the width of the cross section becomes relatively narrow before being fed to the vulcanization process. The cross-sectional shape is the same or almost the same as the cross-sectional shape of the vulcanized product.

(Example) Next, Examples 1 to 3 embodying the present invention will be described.
As will be explained based on the drawings, the method of this example also includes the steps of extruding the raw rubber composition through a die, as in the prior art described above, and vulcanizing the unvulcanized molded product obtained in that step. It consists of a series of steps including the final step of cooling the vulcanized molded product obtained by vulcanization.

As shown in FIG. 1, in the vulcanization process, the unvulcanized molded product 2 from the extrusion process is placed on a belt conveyor 1 and conveyed in the direction shown by the arrow.

The unvulcanized molded product 2 is placed on the belt conveyor 1.
Microwave heaters 3 are installed at intervals necessary for passage of the microwave heaters 3, and a hot air heater (not shown) is installed at the rear following the microwave heaters 3.

On the belt conveyor 1, in front of the microwave heating machine 3, there is a sizing device 5 for unvulcanized molded products 2.
is installed.

As shown in Figures 2 and 3, the belt conveyor 1
The sizing device 5 is mounted on both side walls 7a and 7b of the sizing device 5.
Gate-shaped brackets 6a and 6b are fixed.

A guide support member 9 with an elongated hole 8 is provided at the upper end of the brackets 6a, 6b, and two guide members 1 are attached to the guide support member 9.
Cylindrical sizing bar 1 via 0a, 10b
1a and 11b are each fixed.

The guide members 10a and 10b are fixed to the guide support member 9 by inserting a male screw 12 welded and fixed perpendicularly to the guide member into the elongated hole 8 and tightening the wing nut 13. Further, the sizing bars 11a, 11b are fixed to the guide members 10a, 10b by tightening butterfly bolts 15 to female threads 14 bored in the central portions of the guide members 10a, 10b. ing.

To adjust the distance W between the two guide bars 11a and 11b, loosen the wing nut 13, move one or both of the guide members 10a and 10b in the horizontal direction, and then tighten the wing nut 13.
In addition, to adjust the height of the guide members 11a and 11b, loosen the butterfly bolt 15 and adjust the height of the guide members 11a and 11b.
The butterfly bolt 15 can be tightened after moving a and 11b up and down.

When the sizing device 5 having the above structure is used, the following effects are exhibited in this embodiment.

From the extrusion process, an unvulcanized molded product 2 having a cross-sectional shape shown by a two-dot chain line in FIG. 2 is placed on a belt conveyor 1 and supplied to a microwave heating machine 3.

However, on the way, the unvulcanized molded product 2 is regulated by the sizing bars 11a, 11b of the sizing device 5, and the fins 16a, 1 of the unvulcanized molded product 2 are
6b is in the opposite direction to the sagging due to heat, that is,
This is a deformation in which the width of the cross section becomes relatively narrow, which occurs toward the center of the molded product 2, and the cross-sectional shape is deformed as shown by the solid line in FIG.

The unvulcanized molded product 2 that has passed through this sizing device 5 causes sag as it advances to the front of the microwave heating machine 3, but at the same time, vulcanization begins to progress gradually, and the unvulcanized molded product 2 passes through a hot air heater (not shown). By the time vulcanization is complete, its shape is stable.

In this way, in anticipation of sag during the vulcanization process, a simple sizing device 5 is used on the cross section of the unvulcanized molded product 2 just before being supplied to the vulcanization process, to temporarily prevent sagging due to heat. By applying deformation in the opposite direction, after vulcanization, the cross-sectional shape shown by the two-dot chain line in FIG. 2 (this is also the cross-sectional shape before passing through the sizing device 5) The sulfur molded product 18 can be easily obtained.

Furthermore, the method of the present invention improves quality and does not cause problems in die processing compared to the conventional technique of adjusting the opening of the die.

The sizing device 5 of this embodiment is easy to handle, and the width W and height can be adjusted steplessly.
Moreover, it can be manufactured at low cost.

The degree of cross-sectional deformation described above varies depending on the vulcanization conditions and the raw rubber composition, but is determined in advance through several preliminary experiments.

The present invention is not limited to the configurations of the embodiments described above, but can also be implemented in the following manner, for example.

(1) The raw rubber may be any raw rubber as long as it is a composition that requires vulcanization, such as natural rubber, NBR, SBR, or CR.

(2) The cross-sectional shape of the unvulcanized molded product may be circular or non-circular, but from the viewpoint that the effects of the present invention are particularly exhibited, a non-circular shape is preferable. A non-circular cross-sectional shape in which sulfur molded products are connected is preferred.

(3) The sizing device 5 may have a structure in which the guide bars 11a, 11b are moved parallel to the guide support member 9 by a slider member 17 attached to the brackets 6a, 6b, as shown in FIG.

Effect of the invention The present invention exhibits the following excellent effects.

In the present invention, the cross-sectional shape of the vulcanized molded article after vulcanization can be maintained in the predetermined shape immediately after extrusion by a simple operation.

Further, the method of the present invention does not require excessive equipment, and can be easily carried out by simply incorporating a small amount of equipment necessary for changing the cross-sectional shape of an unvulcanized molded product into conventional equipment. Can be done.

[Brief explanation of drawings]

Figures 1 to 4 are drawings according to the present invention, where Figure 1 is a side view of a microwave heating machine, Figure 2 is a front view of a sizing device in an embodiment, and Figure 3 is an assembled state of the device. FIG. 4 is a partial perspective view of another sizing device, FIGS. 5 to 10 are drawings related to the prior art, FIG. 5 is a process diagram showing a method for manufacturing a molded product, and FIG. 6 is an extrusion process. Figure 7 is a partially cutaway perspective view of the unvulcanized molded product, Figure 8 is a side view of the microwave heating machine, and Figure 9 shows the vulcanized product deformed during the vulcanization process. FIG. 10 is a cross-sectional view of a similarly deformed vulcanized molded product. Unvulcanized long rubber molded product...2, Vulcanized long rubber molded product...18.

Claims (1)

[Claims] 1. Unvulcanized long rubber molded product obtained by extrusion process 2
After deforming the unvulcanized long rubber so that the width of the cross section becomes relatively narrow so that the cross section remains almost the same shape as immediately after extrusion even after vulcanization, the unvulcanized long rubber molding is A method for manufacturing a rubber extrusion molded product, characterized in that the product 2 is supplied to a vulcanization step and vulcanized, so that the shape of the cross section of the vulcanized long rubber molded product 18 is maintained. 2. The method for producing a rubber extrusion molded product according to claim 1, wherein the rubber molded product 2 is a molded product of an ethylene-propylene-diene rubber composition.