JPH1071615A - Rubber kneader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubber kneader capable of continuously and quantitatively supplying chemicals to enhance the mixing accuracy of rubber and chemicals. SOLUTION: In a rubber kneader consisting of a screw extruder 3 wherein a screw 2 is housed in a cylinder 1, a rubber supply hopper 4 for supplying rubber into the cylinder 1 and a chemical supply device 5 for supplying chemicals into the cylinder 1 on the downstream side of the screw extruder 3, the supply means of the chemical supply device 5 is composed of a twin- screw.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a rubber kneader. More specifically, the present invention relates to a rubber kneader capable of continuously and quantitatively mixing chemicals to be added to rubber.

[0002]

2. Description of the Related Art Conventionally, as a device for mixing rubber and chemicals, a rubber supply hopper and chemical supply means have been installed in a screw extruder in which a kneading screw is housed in a cylinder. There is a method in which extrusion molding including a step, a kneading step, and a compression step is continuously performed (Japanese Patent Application Laid-Open No. 5-38715). As a chemical supply means in such an apparatus, a 1
A screw rod of the shaft is used, and the chemical is screwed into the rubber by the rotation of the screw rod, and the rubber is stirred.

[0003]

However, the above-mentioned 1
In the case of chemicals with a low coefficient of friction, such as carbon, etc., relative slippage between the screw shaft and the chemical is likely to occur on the shaft screw rod, and chemicals that easily generate static electricity, such as sulfur, when chemicals such as sulfur are used. May easily adhere to the screw shaft, making it difficult to supply the chemical quantitatively into the cylinder.

[0004] In addition, with the single-screw rod, it is not possible to prevent the force of suppressing the supply of chemicals due to the filling pressure of the rubber supplied into the screw or the extrusion pressure of the screw compression section, and the chemicals are quantitatively introduced into the cylinder. There is a problem that is difficult to supply.

[0005] In view of the circumstances described above, an object of the present invention is to provide a rubber kneader capable of quantitatively supplying chemicals and improving the mixing accuracy of rubber and chemicals.

[0006]

The rubber kneader of the present invention comprises:
A screw extruder containing a screw in a cylinder, a rubber supply hopper for supplying rubber into the cylinder, and a chemical supply device for supplying a chemical into the cylinder downstream of the screw extruder Wherein the supply means of the chemical supply device comprises a twin screw.

[0007] When the chemical is a chemical, it is preferable that the twin screw be a gear pump.

[0008] In the process of extrusion molding of rubber and chemicals,
It is preferable that an adjusting means for adjusting a rubber conveyance amount per one rotation of the screw is provided.

The adjusting means is a ring which is detachably attached to a screw rotatably provided in a cylinder of the screw extruder and which can be divided into two parts. It is preferable that a regulating means for regulating the amount of rubber transport is provided.

The ring is a substantially cylindrical main body, and the regulating means for regulating the amount of rubber transported in the cylinder is one or more slits formed on the outer surface of the main body. preferable.

The ring is a substantially cylindrical main body, and the restricting means for restricting the amount of rubber conveyed is one or two or more holes formed so as to penetrate the main body in the longitudinal direction. Is preferred.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rubber kneader according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a plan view showing one embodiment of the rubber kneader of the present invention, FIG. 2 is a side view of the rubber kneader shown in FIG.
FIG. 4 is a perspective view showing the medicine supply device in FIG. 1, and FIG.
5 is a partial cross-sectional view showing another arrangement of the biaxial screw, FIG. 5 is a partial cross-sectional view showing another arrangement of the biaxial screw, FIG. 6 is a cross-sectional view showing an embodiment of the adjusting means, and FIG. FIG. 8 is a sectional view showing another embodiment of the means, and FIG.
FIG. 9 is a sectional view showing still another embodiment of the adjusting means, and FIG. 10 is a sectional view showing still another embodiment of the adjusting means. FIG. 11 is an explanatory view showing a state in which the adjusting means according to another embodiment of the present invention is removed from the screw, FIG. 12 is an exploded perspective view showing the adjusting means attached to the screw in FIG. 11, and FIG. FIG. 14 is an explanatory view showing a state where the adjusting means is attached to the screw, FIG. 14 is an explanatory view showing an example of the adjusting means according to still another embodiment of the present invention, and FIG. 15 is a kneader provided with the adjusting means of FIG. It is explanatory drawing which shows an example of.

As shown in FIGS. 1 to 4, the rubber kneader includes a screw extruder 3 having a screw 1 housed in a cylinder 1, and a rubber supply hopper 4 for feeding rubber into the cylinder 1. And a drug supply device 5 for supplying a drug into the cylinder 1 on the downstream side of the screw extruder 3.

A rotary drive 6 for rotating the screw 2 is connected to the screw extruder 3. As the rotation driving device 6, for example, a device that rotates the screw 2 via a speed change gear by a driving source of an electric motor can be used. As the cylinder 1, a cylinder in which a plurality of cylinders 1a, 1b, 1c and 1d are connected is used. The rubber supply hopper 4 is connected to the opening 7 and is arranged in the cylinder 1a. The rubber supply hopper 4 is normally directed upward, but may be inclined depending on the working method, and the direction is not particularly defined. The medicine supply devices 5 are provided at openings 8 formed on both side walls of the cylinder 1b in order to uniformly supply and mix the medicine with the rubber. The installation position of the chemical supply device 5 varies depending on the screw design of the kneading machine. However, since it is important to stabilize the feed amount per one rotation of the screw, the screw lead from the rubber supply hopper 4 is usually used. It is preferable to set the position at a distance of about 1.0 or more. In this embodiment, the screw 9 of the screw 2
Is a two-start thread over its entire length, but the present invention is not limited to this. Alternatively, a double thread may be used up to the position of the drug supply device 5 and a single thread may be provided from the position of the drug supply device 5 to the extrusion port 10.
A single chemical, for example, carbon is used as the chemical, but if there are many kinds of chemicals, a mother stock in which several chemicals are mixed in advance can be used. When the chemical is a chemical, a pipe may be connected instead of the twin screw to supply a constant amount of the chemical. As a means for supplying such a chemical solution, for example, a gear pump can be used, but the present invention is not limited to this, and other devices such as a single-axis eccentric screw pump can be used as long as it can perform constant-quantity continuous feeding. Can be.

The chemical supply device 5 comprises a hopper 11, a supply means disposed below the hopper 11, and a drive unit 12 for driving the supply means. , A biaxial screw 13 in which peaks and valleys are arranged so as to correspond to each other. Further, the hopper 11 is provided with a stirrer 14 for enabling the medicine in the hopper 11 to be smoothly supplied onto the twin screw 13.

When the biaxial screw 13 and the cylinder 15 enclosing the screw are inserted into the opening 8 of the cylinder 1b, the tips 16, 17 are set at the inner wall surface 1 of the cylinder 1b.
8 to stay. In this embodiment,
Although the tips 16 and 17 are flush with the inner wall 18, the present invention is not limited to this.
As shown in FIG.
A slit 19 through which the screw 3 can pass may be formed so that the tip 16 of the biaxial screw 13 projects into the cylinder 1b. Conversely, depending on the screw design of the kneader, the resistance applied to the tip of the twin screw of the chemical supply device may increase, and in this case, the variation in the amount of chemical supply may increase. The tip of the screw may be withdrawn from the inner wall surface 18. FIG.
It is preferable to keep the screw tip 16 on the inner wall surface 18 in that the resistance of the biaxial screw tip of the drug supply device can be eliminated.

In the present invention, as shown in FIG. 2, between the rubber and chemical extrusion molding steps, ie, between the rubber supply step 21, the chemical supply step 22, the kneading step 23 and the compression step 24, the screw is removed. By providing the adjusting means A for adjusting the amount of rubber transported per rotation, stable mixing can be expected.

As the adjusting means A, between the rubber supply step and the chemical supply step, in order to secure a space for the supply of the chemical supplied from the chemical supply device to the rubber, the chemical supply to the rubber supply step is performed. There is a method of increasing the amount of rubber transport in the process. Between the chemical supply step and the kneading step, there is a method in which the amount of rubber transported in the kneading step is made larger than that in the chemical supply step in order to lower the cylinder internal pressure in the chemical supply step. Also, between the kneading step and the compression step, it is preferable to increase the rubber conveyance amount in the compression step with respect to the kneading step. However, for the same screw diameter, generally, when the compression is increased, the transport amount of the rubber often decreases, so that the transport amount of the rubber in the compression step has to be smaller than the transport amount in the kneading step. However, in this case, it is better to increase the transport amount in the compression step than in the chemical supply step.

Regarding the third means, when the product is extruded directly from the rubber discharge portion, as mentioned above, there is a means for increasing the screw diameter as a means for increasing the conveying ability and the compressing ability in the compression step.

In addition, for example, as the adjusting means A between the rubber supply step and the chemical supply step, as shown in FIG. 6, a screw screw 25 in the rubber supply step 21 and a screw screw 26 in the chemical supply step 22 are provided. It can be a cylindrical part 27 with a slit for adjusting the flow of the formed rubber. This slit cylindrical part 2
7 can be inclined as shown in FIG. When the adjustment is performed by the cylindrical portion 27 with the slit, the degree of the rubber transport amount is changed by changing the size of the cylindrical portion 27 with the slit in the screw length direction or by changing the size of the slit 28 shown in FIG. Can be changed. Further, as shown in FIG.
And between the screw screw 29 in the chemical supply step 22 and the screw screw 30 in the
The weir 31 having a gap between the inner wall surface 18 of FIG. The weir 31 is not limited to this, and as shown in FIG.
A screw weir 32 having a clearance between the screw wall 29 of the cylinder 1 and the inner wall surface 18 of the cylinder 1a may be used. In addition, the said cylindrical part 27 with a slit, the weir 31 and the screw weir 32 are provided in the rubber supply hopper 4 side from the biaxial screw 13. Further, the pitch (lead) of the screw is 0.2D to 1.6D, the root diameter is 0.4D to 1.0D, or the screw diameter (outer diameter = D).
Can be adjusted to adjust the rubber conveyance amount.

Referring to FIGS. 11 to 13, an adjusting means A according to another embodiment of the present invention includes a pair of cylindrical portions A _1.
And a A ₂ and. The cylindrical portions A ₁ and A ₂ include a first portion 51a, 52a and a second portion 51b, respectively.
52b. First part 5 of cylindrical part A ₁
1a and a portion of the first portion 52a of the cylindrical portion A ₂ and the second portion 52b and the bolt insertion holes 50a so as to abut
And (see FIG. 12) bolts tapped hole 50b is positioned a cylindrical portion A ₁ and A ₂ are fixed by bolting to surround around the screw 2.

In the case of the present embodiment, the regulating means R for regulating the amount of rubber conveyed in the cylinder 1 is a cylindrical portion A ₁
And a slit 100 formed one or more on the outer circumferential surface of the A _2.

FIG. 14 shows an adjusting means A according to still another embodiment of the present invention. The structure of this is the same as the adjusting means A shown in FIGS.

In the case of the present embodiment, the regulating means R is one or more holes 150 penetrating through the cylindrical portions A ₁ and A ₂ in the longitudinal direction.

In the case of the adjusting means A shown in FIGS. 6 to 10, since the adjusting means A is formed integrally with the screw, it cannot cope with a change in the rubber compounding. It is necessary to prepare a screw in which is formed in advance. On the other hand, in the case of the adjusting means A shown in FIGS. 11 to 15, the predetermined adjusting means A can be appropriately replaced according to the compounding amount of the rubber.

[0027]

As described above, according to the present invention,
Because the supply means of the chemical supply device is a twin screw,
Chemicals can be mixed with rubber continuously and quantitatively regardless of the nature or type of the chemicals.

Also, while the rubber supplied from the rubber supply device is being conveyed to the tip of the screw, by adjusting the amount of rubber conveyed, the supply and mixing of the chemicals can be carried out smoothly.

[Brief description of the drawings]

FIG. 1 is a plan view showing one embodiment of a rubber kneader of the present invention.

FIG. 2 is a side view of the rubber kneading machine shown in FIG.

FIG. 3 is a perspective view showing the medicine press-fitting device in FIG.

FIG. 4 is a partial cross-sectional view showing an arrangement of a twin screw in FIG. 2;

FIG. 5 is a partial cross-sectional view showing another arrangement of the twin screw.

FIG. 6 is a sectional view showing an embodiment of the adjusting means.

FIG. 7 is a sectional view showing another embodiment of the adjusting means.

FIG. 8 is a sectional view taken along line XX in FIG. 6;

FIG. 9 is a sectional view showing still another embodiment of the adjusting means.

FIG. 10 is a sectional view showing still another embodiment of the adjusting means.

FIG. 11 is an explanatory view showing a state in which an adjusting means according to another embodiment of the present invention has been removed from a screw.

FIG. 12 is an exploded perspective view showing an adjusting means attached to the screw of FIG. 11;

FIG. 13 is an explanatory view showing a state in which the adjusting means of FIG. 12 is attached to a screw.

FIG. 14 is an explanatory diagram illustrating an example of an adjusting unit according to still another embodiment of the present invention.

FIG. 15 is an explanatory view showing an example of a kneader provided with the adjusting means of FIG.

[Explanation of symbols]

1, 1a, 1b, 1c, 1d Cylinder 2 Screw 3 Screw extruder 4 Rubber supply hopper 5 Chemical supply device 6 Rotary drive device 7, 8 Opening 9 Screw 10 Extrusion port 11 Hopper 12 Drive unit 13 Biaxial screw 21 Rubber supply Step 22 Chemical supply step 23 Kneading step 24 Compression step 100 Slit 150 Hole A Adjusting means A ₁ , A ₂ Cylindrical part R Regulation means

Claims (6)

[Claims] 1. A screw extruder having a screw accommodated in a cylinder, a rubber supply hopper for supplying rubber into the cylinder, and a chemical supplied into the cylinder downstream of the screw extruder. A rubber kneading machine comprising a chemical supply device for supplying a chemical, wherein the supply means of the chemical supply device comprises a twin screw. 2. The rubber kneader according to claim 1, wherein when the chemical is a chemical, the twin screw is a gear pump. 3. The rubber kneader according to claim 1, wherein an adjusting means for adjusting a rubber conveying amount per one rotation of the screw is provided in a step of extruding the rubber and the chemical. 4. A ring in which said adjusting means is detachably mounted on a screw rotatably provided in a cylinder of a screw extruder and which can be divided into two parts. The rubber kneading machine according to claim 3, further comprising a regulating means for regulating a rubber transport amount. 5. The ring is a substantially cylindrical body,
5. The apparatus according to claim 4, wherein said regulating means for regulating the amount of rubber transported in the cylinder is one or more slits formed on an outer surface of the main body. 6. The ring is a substantially cylindrical body,
5. The apparatus according to claim 4, wherein the regulating means for regulating the amount of rubber transported in the cylinder is one or more holes formed so as to penetrate the main body in the longitudinal direction.