JP2000117813A - Rubber extrusion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily form a new rubber sectional region on the opposite side of an extruder while enlargement of the extruder is not generated and the change of a preformer-set is restricted as small as possible by a method wherein the rubber discharging from one extruder is allowed to flow by branching into this side and the back face side of the extruder. SOLUTION: In a first preformer 7, a plurality of kinds of rubber are discharged through a plurality of feed openings 11 arranged in the longitudinal direction of the preformer 7 to an inflowing port 4. On an inflowing surface Si, a first and a second branched imflowing parts 14A and 14B, which dividedly accept a rubber sent through one feed opening 11, are provided. At the same time, on an outflowing surface So, an outflowing port 5 including a first and a second branched outflowing parts 15A and 15B, to which the rubbers sent from the first and the second branched inflowing parts 14A and 14B are separated, is formed. A second preformer 9 koins the rubbers sent from the separated first and second branched outflowing parts 15A and 15B and finally sends out through a sending-out port 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber extruder for extruding a rubber extruded body such as a rubber member for forming a tire, the cross section of which is divided into a plurality of regions by rubber from a plurality of rubber extruders. About.

[0002]

2. Description of the Related Art As shown in FIG. 13, a sidewall portion A of a white letter tire in which a mark B such as a character is displayed by a white rubber on a sidewall portion A is generally provided with a white rubber Ra for forming a white character. A rubber extruded body R1 in which a black side warm rubber Rb vertically connected to the white rubber Ra and a clinch rubber Rc for preventing rim dislocation arranged below the lower side warm rubber Rb are integrally joined to a carcass. It is formed by sticking to the outer surface of C.
That is, the rubber extruded body R1 has
It is divided into four cross-sectional areas Y1 to Y4 composed of the three types of rubbers Ra, Rb and Rc.

Conventionally, this rubber extruded body R1 discharges each of the rubbers Ra, Rb and Rc as shown in FIG.
Extruders Ma, Mb, Mc are preformer set F
And extruded from the extruder Mb in the lateral direction (longitudinal direction of the horizontal cross section) and extruded.
White rubber Ra (cross-sectional area Y2) from the extruder Ma is introduced between b and Rb (cross-sectional area Y1, Y3). At this time, the small-sized extruder Ma having a small rubber discharge amount is mounted above the large-sized extruder Mb having a large rubber discharge amount. Also, on the opposite side (back side) of the extruders Ma and Mb,
By attaching the extruder Mc for discharging the clinch rubber Rc, the sectional area Y4 is formed on the back side of the sectional area Y3.

On the other hand, in recent years, as shown in FIG. 11, five cross-sectional areas Y5 having a cross-sectional area Y5 made of a side warm rubber Rb are provided on the back of the cross-sectional areas Y1 and Y2.
It is desired to use a rubber extruded body R having 1 to Y5. The reason is that the white rubber Ra is inferior in adhesion to the side warm rubber Rb, and the formation of the cross-sectional area Y5 can eliminate direct contact between the white rubber Ra and the carcass C. It is possible to effectively prevent peeling damage at a part. In addition, since the formation of the cross-sectional area Y5 reduces the amount of the expensive white rubber Ra used, there is an advantage that the cost can be reduced.

[0005]

However, in the structure of the conventional preformer set F, the side wall rubber Rb from the extruder Mb is separated from the upper extruder Ma by the upper extruder Ma.
It is difficult to wrap around the other side beyond the white rubber Ra from the front side of the preformer set F. Therefore, a new extruder Md (shown by a chain line in FIG. Need to be provided for as a result,
In addition to an increase in the number of extruders, there is a problem in that a preformer set and equipment must be significantly changed.

Accordingly, the present invention allows the rubber discharged from the extruder to branch and flow to the near side and the back side, without increasing the number of extruders and minimizing the change of the preformer set. It is another object of the present invention to provide a rubber extruder capable of easily forming a new cross-sectional area Y5 on the back side of the cross-sectional area Y2.

[0007]

In order to achieve the above object, the invention of claim 1 of the present application is directed to a horizontally long section divided into a plurality of cross-sectional areas formed by rubber discharged from a plurality of rubber extruders. A rubber extruder for molding a rubber extruded body having a cross section of a preformer set using a preformer set, wherein the preformer set has flowed into a plurality of inflow surfaces having an inlet opening for receiving rubber from the rubber extruder. A first base former having a plurality of outlets for discharging rubber, and an outlet surface having an opening, a first preformer attached to at least one of the inlet surfaces of the first base former, and the first base former; A second preformer disposed on the outflow surface of the second baseformer, and a second baseformer that fits the second preformer between the second preformer and the first baseformer. The first preformer is provided with a plurality of rubbers from a plurality of supply ports to which a plurality of types of rubber are supplied in a line in a length direction of the first preformer, and the first preformer is attached to the first preformer. A first and a second branch inflow portion are provided on the preformer inflow surface for discharging the rubber from the one supply port while discharging to the inflow port of the preformer inflow surface that is an inflow surface, and Forming an outlet on the outflow surface including first and second branch outflow portions for separating and discharging rubber from the first and second branch inflow portions;
And the second preformer forms the divided rubber in which the rubber from the separated first and second branch outflow portions is temporarily divided into the different cross-sectional areas, and sends the divided rubber to the second base former from an outlet. Moreover, this second base former
The method is characterized in that the rubber segment is formed into the rubber extruded body.

According to a second aspect of the present invention, the first and second preformers comprise a pair of long shafts each forming a supply port or a delivery port on a mating surface.

According to a third aspect of the present invention, the first base former has a triangular cross section, and two surfaces are the inflow surfaces.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a conceptual diagram showing a rubber extruder 1 of the present invention. In the figure, reference numeral 2 denotes a preformer set for molding a rubber extruded body R, and reference numeral 3 denotes a state in which the preformer set 2 is held. It is a head for fixing the discharge ports of a plurality of rubber extruders M. Symbol 8
Is the preformer set 2 for the rubber from each rubber extruder M
This is a guide channel that leads to

In this embodiment, the rubber extruder 1 is
FIG. 11 illustrates a case where a rubber extruded body R which is a rubber member for forming a sidewall portion of a white letter tire is molded. This rubber extruded body R has a horizontally long cross section formed by a cross-sectional area Y1 made of a sidewall rubber Rb.
Y3, Y5, a cross-sectional area Y2 made of white rubber Ra,
It is divided into five regions including a cross-sectional region Y4 made of the clinch rubber Rc. The cross-sectional areas Y1, Y2, Y3
Are formed on the near side of the horizontally long cross section, and the cross-sectional areas Y4 and Y5 are formed on the back side thereof and are arranged in the longitudinal direction.

Next, the preformer set 2 is shown in FIG.
As described above, in this example, the first extruder has a plurality of inflow surfaces Si in which the inflow ports 4 for receiving the rubbers Ra to Rc from the three rubber extruders Ma to Mc are open, and an outflow surface So in which the outflow port 5 is open. Base former 6, this first base former 6
The first preformer 7 attached to one of the inflow surfaces Si, and the outflow surface So of the first base former 6
And a second base former 10 in which the second preformer 9 is fitted between the second preformer 9 and the first base former 6.

The first base former 6 has a triangular cross section in this embodiment, and has a bottom surface formed as the outflow surface So. Further, the two slopes are formed as inflow surfaces Sif and Sir, and the inflow surface Sif on the near side where the first preformer 7 is attached is hereinafter referred to as a preformer inflow surface, and the inflow surface Sir on the rear side is referred to as a non-preformer. Sometimes called the inflow surface. In the present application, for convenience, the side to which the rubber extruder Mb is attached is called the near side, and the opposite side is called the back side.

As shown in FIGS. 2 and 3, the first preformer 7 is provided with a plurality (two in this example) of rubbers Ra and Rb arranged in the longitudinal direction (in this example). (3) independent supply ports 11 and discharge ports 12 for discharging the rubbers Ra and Rb from the supply ports 11 to the inflow port 4f of the preform inlet surface Sif.

The first preformer 7 is, in this example,
A pair of upper and lower long shaft bodies 7U, 7L butting the mating surfaces 13
The supply port 11 and the discharge port 12 are formed by cutting out the respective mating surfaces 13. That is,
The rubber Ra supply port 11a is connected to the upper long shaft 7U and the rubber R
The supply ports 11b1 and 11b2 of b are formed on the long shaft 7L on both sides thereof and below. Each supply port 11a, 11b1,
As schematically illustrated in FIG. 4, 11b2 communicates with the discharge ports 12a, 12b1, and 12b2 that are arranged in close proximity to one another by making the slopes of the rubber flow paths different from each other.

In the present embodiment, the inflow port 4f provided on the preformer inflow surface Sif is formed of first and second branch inflow portions 14A and 14B which receive the rubber Rb from the supply port 11b1 by vertically branching. Is done. The first branch inflow portion 14A is opened at a position facing the upper portion of the discharge port 12b1, as shown in FIG.
Only a part of the rubber Rb from b1 can branch and flow.
The second branch inflow portion 14B is capable of flowing in the remaining rubbers Ra and Rb by opening horizontally across the lower portion of the discharge port 12b1 and the discharge ports 12a and 12b2.

In order to reliably prevent another rubber Ra from flowing in from the first branch inflow portion 14A, the discharge ports 12a, 12b1, 12b are provided as in this embodiment.
2 are preferably formed independently of each other, but the discharge ports 12a, 12b1, and 12b2 may be formed as one large opening connected to each other as required.

An outlet 5f formed of first and second branch outlets 15A and 15B for separating and discharging rubber from the first and second branch inlets 14A and 14B is provided at the outlet surface So. Equipped.

That is, as schematically shown in FIG. 7, the rubbers Ra and Rb flowing from the second branch inflow portion 14B are:
The first rubber former 17 is joined to each other in the first base former 6 to form a first rubber joined body 17 whose section is provisionally divided into provisional sectional areas YA1 to YA3, and is discharged from the second branch outflow portion 15B.
From the first branch outflow portion 15A, a rubber body 19 of the rubber Rb which branches out from the first branch inflow portion 14A and flows in is discharged. The outflow surface So has a rubber Rc from an inflow port 4r provided on the non-preformer inflow surface Sir.
Is formed as a rubber body 20 in parallel with the first branch inflow portion 14A in the longitudinal direction.

FIG. 5 shows the first base former 6
In the present example, the second branch inflow portion 14B and the second branch inflow portion 14B
Is substantially the same length as the branch outflow portion 15B, and
r and the outlet 5r are formed to have substantially the same length. On the other hand, in the first branch outflow portion 15A, the first branch inflow portion 14A is extended in the longitudinal direction to thereby provide the first branch inflow portion 14A.
It is necessary to have an extended portion 16 which is longer than A and can overlap with the temporary section area YA2.

The second preformer 9 is shown in FIGS.
As shown in the figure, the first and second branch outflow portions 15A, 15B
Opening 22a which opens at each position facing the outlet 5r
To 22c, and the opening portions 22a to 22c are gathered in one delivery port 23. As a result, the first rubber bonded body 17 and the rubber bodies 19 and 20 which are separately discharged are bonded to each other, and the second rubber bonded body 21 (see FIG. 9) whose cross section is provisionally divided into temporary cross-sectional areas YA1 to YA5. 7) and is discharged from the delivery port 22.

In the present embodiment, the second preformer 9
Like the first preformer 7, the pair of long shafts 9f and 9r are joined with the mating surface 25, and the openings 22a to 22c and the delivery port 23 are connected to each mating surface 2a.
5 is formed by notching. That is, the first
The opening 22a for receiving the rubber bonded body 17 is formed on the long shaft 9f on the front side, and the openings 22b and 22c for receiving the rubbers 19 and 20 are formed on the long shaft 9r on the back.

The openings 22a to 22c can be formed as independent openings. However, it is preferable to form the openings as one continuous large opening as in the present embodiment in order to stabilize the rubber flow.

Further, the second base former 10 is provided with a nozzle fitting 24 similar to the conventional one at the lower end thereof, and as shown in FIG. The rubber extruded body R is formed into a shape.

FIG. 7 shows that in preformer set 2,
The state of the change in the cross-sectional shape until the rubbers Ra, Rb, and Rc to be charged are formed as the rubber extruded body R is schematically illustrated.
In this example, the first base former 6 has an inlet 4f formed of first and second branch inflow portions 14A and 14B that receive the rubber Rb from one supply port 11b1 separately.
First and second branch outflow portions 15A, 15A that separate and discharge rubber from the first and second branch inflow portions 14A, 14B.
An outflow portion 5f made of 5B is formed.

Accordingly, the rubber body 19 for forming the cross-sectional area Y5 is branched from the rubber Rb from the supply port 11b1, and the branched rubber body 19 is extruded by the extruder Mb.
To the opposite side (back side).
Also, the preformer set 2 of this example can be achieved by changing the elongated body 9r of the first base former 6 and the second preformer 9 with respect to the conventional preformer set 2, and the like. It is possible to minimize the number of installations and to minimize the change of equipment.

FIG. 8 is a cross-sectional view of the preformer set 2 taken along the line L1 in FIG. 5, and FIG.
FIG. 10 is a cross-sectional view when cut at the position L3, and FIG. 10 is a cross-sectional view when cut at the position L3.

In the present application, the rubber member for forming a sidewall portion of a tire can be used for forming a rubber extruded body for various uses without being limited to the rubber member. Also, the structure can be changed to various structures without being limited to the three rubber extruders of this example, for example.

[0029]

Since the present invention is configured as described above,
The rubber discharged from one extruder can be branched and flowed to the near side and the back side, and the opposite side of the extruder can be used without increasing the number of extruders and minimizing the change of the preformer set. Thus, a new rubber cross-sectional area can be easily formed.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing one embodiment of the present invention.

FIG. 2 is an exploded perspective view of a preformer set.

FIG. 3 is a front view of a first preformer.

FIG. 4 is a conceptual diagram schematically showing a rubber flow passing through a first preformer.

FIG. 5 is a diagram showing a comparison between an inflow port and an outflow port of the first base former.

FIG. 6 is a front view of a second preformer.

FIG. 7 is a diagram schematically showing a change in cross-sectional shape until rubber to be charged is formed as a rubber extruded body.

8 is a cross-sectional view when the preformer set 2 is cut at the position of L1 in FIG.

9 is a cross-sectional view when the preformer set 2 is cut at a position L2 in FIG.

FIG. 10 is a cross-sectional view when the preformer set 2 is cut at the position of L3 in FIG.

FIG. 11 is a diagram showing an example of a rubber extruded body formed by the apparatus of the present application.

FIG. 12 is a conceptual diagram of an apparatus for explaining a conventional technique.

FIG. 13 is a diagram showing an example of a rubber extruded body formed thereby.

[Explanation of symbols]

 2 Preformer set 4, 4f, 4r Inlet 5, 5f, 5r Outlet 6 First base former 7 First preformer 7U, 7L, 9f, 9r Long shaft body 9 Second preformer 10 Second Base former 11, 11a, 11b1, 11b2 Supply port 13, 25 Fitting surface 14A, 14B First, second branch inflow part 15A, 15B First, second branch outflow part 21 Division rubber 23 Delivery port M, Ma, Mb, Mc rubber extruder R rubber extruded body Ra, Rb, Rc rubber Si inflow surface Sif preformer inflow surface So outflow surface Y1 to Y5 cross-sectional area

Claims (3)

[Claims] 1. A rubber extruder for molding a rubber extruded body having a horizontally long cross section divided into a plurality of cross sectional areas formed by rubber discharged from a plurality of rubber extruders using a preformer set. The preformer set has a first base former having a plurality of inflow surfaces having an inlet opening for receiving rubber from the rubber extruder and an outflow surface having a plurality of outlets for flowing in rubber. A first preformer mounted on at least one of the inflow surfaces of the first baseformer, a second preformer disposed on an outflow surface of the first baseformer, and the first baseformer; And a second base former for fitting the second preformer between the first preformer and the first preformer in a longitudinal direction of the first preformer. And discharging rubber from a plurality of supply ports to which a plurality of types of rubber are supplied to the inflow port of the preformer inflow surface, which is the inflow surface to which the first preformer is attached, and the preformer inflow surface A first and a second branch inflow portion for separately receiving the rubber from the one supply port,
And an outflow port including first and second branch outflow portions that separates and outputs rubber from the first and second branch inflow portions is formed in the outflow surface; and the second preformer includes: The separated rubber from the first and second branch outflow portions is formed into a divided rubber that is temporarily divided into the different cross-sectional areas, and is sent from the delivery port to the second base former, and furthermore, the second base former is A rubber extruder for molding the divided rubber into the rubber extruded body. 2. The rubber extruder according to claim 1, wherein the first and second preformers are each composed of a pair of long shafts forming a supply port or a delivery port on a mating surface. 3. The rubber extruder according to claim 1, wherein the first base former has a triangular cross section and two surfaces are the inflow surfaces.