JPH10128740A - Twin-screw kneader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable defoaming while preventing a kneading degree of kneaded matter from becoming high by providing an emitting side feed blade part and a defoaming means on the downstream side of the kneading blade part of a rotor and squeezing the kneaded matter sent by this blade part into a chamber to stagnate the same under suction. SOLUTION: Two rotors 7 are parallelly provided in a chamber 6 having a material charging port 2 and a taking-out port 3 in a freely rotatable manner and a feed blade part 10, a kneading blade part 11 and an emitting side feed blade part 12 are provided to each of the rotors 7. Kneaded matter is sent to the kneading blade parts 11 by the feed blade parts 10 to be kneaded between the outer peripheral ends of the kneading blade parts 11 and the inner surface of the chamber 6 to be sent to a squeezing part 21 by the emitting side feed blade parts 11. When the kneaded matter is stagnated on the upstream side of the squeezing part 21, a gate device 25 is opened to send the kneaded matter to the taking-out port 3 by the emitting side feed blade parts 21. A defoaming means 19 is operated from this point of time and the chamber 6 is evacuated from a vent port 18 to defoam the kneaded matter on the downstream side of the squeezing part 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a twin-screw kneader for melting and kneading resin materials and the like.

[0002]

2. Description of the Related Art Biaxial kneaders for melting and kneading resin materials and the like (see, for example, Japanese Patent Publication No. 6-41135).
As shown in FIG. 8, the material inlet 81 and the material outlet 8
A rotor 86 is rotatably provided in the chamber 84 of the apparatus main body 83 having the feed blades 81 and 82 between the ports 81 and 82.
8 and a kneading wing portion 89 are provided. Rotor 8
6 are parallel to each other, and the chamber 84 of the apparatus main body 83 also has a gourd-shaped cross section so as to surround each rotor 86 with a uniform gap.

Therefore, when a resin material or the like is supplied from the material input port 81 of the apparatus main body 83 while rotating both rotors 86 in this twin-screw kneader, the outer peripheral end of the kneading wing portion 89 and the inner surface of the chamber 84 are formed. The kneaded material receives a large shearing force, is melted and kneaded, and is thereafter taken out from the material outlet 82 of the apparatus main body 83. In this type of twin-screw kneader, a circular section 91 having a rotation axis as a center is provided at the downstream end of the kneading wing section 89 with respect to the rotor 86. Gate device 93 that allows the weir piece 92 to approach and separate
Some are provided. The gate device 93 allows the kneaded material to stay on the upstream side of the weir piece 92, that is, at a portion corresponding to the kneading wing portion 89 of the rotor 86 by bringing the weir piece 92 close to the circular cross section 91 of the rotor 86, This allows the degree of kneading of the kneaded material to be adjusted.

[0004] Generally, the apparatus main body 83 includes a rotor 8.
The vent port 94 is located at a position downstream of the kneading wing portion 89 of FIG.
Is provided, and air, volatile gas and the like in the kneaded material can be defoamed and removed from the vent port 94 by defoaming means 95 capable of evacuating the inside of the chamber 84. In the twin-screw kneader provided with both the gate device 93 and the defoaming means 95 as described above, the gate device 93 is also operated when the defoaming is performed by the defoaming means 95, and the weir piece 92 is connected to the circular section of the rotor 86. It was made to approach the part 91. This reduces the gap formed between the circumference of the weir piece 92 and the circular cross-section 91, and fills this circumferential gap with the kneaded material so that the vacuuming action does not reach the material inlet 81. That is, it is to prevent the intake of air from the material inlet 81. This is because if air is taken in from the material input port 81, oxygen in the air is caught in the kneaded material, which leads to oxidative deterioration of the kneaded material, and it was necessary to prevent this. .

[0005]

When the gate device 93 is operated to perform defoaming by the defoaming means 95, the time for which the kneaded material is kneaded by the kneading blade portion 89 of the rotor 86 is inevitably increased. For this reason, the degree of kneading of the kneaded material increases, and depending on the material of the kneaded material, there is a possibility that the quality may be deteriorated due to an excessively high temperature or excessive shearing.

[0006] In other words, in other words, the defoaming means 9
In the case of performing the defoaming by 5, the gate device 93 must be operated in the closing direction, and it is necessary to maintain this state. As a result, the kneading degree cannot be adjusted. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a twin-screw kneader capable of performing defoaming by a defoaming unit without unnecessarily increasing the kneading degree of a kneaded material. And

Another object of the present invention is to provide a twin-screw kneader capable of adjusting a kneading degree by a gate device even when defoaming is performed by a defoaming means.

[0008]

According to the present invention, the following technical measures have been taken in order to achieve the above object. That is, in the present invention, the rotor provided in the chamber of the apparatus main body includes a feeder wing portion on the material input port side, a kneading wing portion, and a discharge feed wing portion on the material discharge port side along the axial direction. Have.

On the other hand, the apparatus main body is provided with a throttle portion corresponding to an intermediate portion or a downstream end portion of the discharge-side feed blade portion of the rotor, and defoaming further downstream than the throttle portion. Means are provided. The throttle portion is, literally, a portion that narrows the inside of the chamber, thereby reducing a gap formed between the circumference of the throttle portion and the rotor, and filling the gap with the kneaded material sent by the discharge-side feed blade. Therefore, the kneaded material is caused to stay at the upstream portion of the throttle portion (the upstream portion corresponds to the periphery of the discharge-side feed blade portion). To give a specific example of the structure of the throttle unit, a circular cross-section centered on the rotation axis is provided for the rotor, and a weir piece approaches and separates around the circular cross-section on the device body side. It is possible to adopt a structure in which a gate device is provided.

As is apparent from the above, the discharge-side feed blade of the rotor plays a role of keeping a predetermined axial distance from the downstream end of the kneading blade to the corresponding portion where the throttle portion is provided. In this part, the stay of some kneaded material can be absorbed. That is, even if the kneaded material is retained on the upstream side of the throttle portion, the kneaded material is subjected to the feeding action by the discharge-side feed blade portion but is not kneaded by the kneading blade portion. It is not raised.

If the kneaded material stagnates on the upstream side of the throttle, the air flow between the portion where the defoaming means is disposed and the material supply port side is shut off in the chamber of the apparatus main body. Therefore, at the time of defoaming by the defoaming means, air is not taken into the chamber from the material supply port. The throttle section is not limited to the above structure.For example, a circular cross section centered on the rotation axis is provided for the rotor, and a weir wall protruding from the inner surface of the chamber is provided near the circular cross section. It is also possible to make it a structure to make it.

In addition, a space capable of accommodating the amount of the kneaded material stagnating in the throttle portion is secured between the periphery of the inner peripheral surface of the chamber and the discharge side feed blade portion from the kneading blade portion of the rotor to the throttle portion of the apparatus main body. Needless to say, it is preferable to do so. The rotor has a circular cross-section centered on the rotation axis with respect to the connection boundary between the kneading blade and the discharge-side feed blade, and the device body has a weir piece around the circular cross-section. Can be provided with a gate device capable of approaching / separating. This gate device is for adjusting the degree of kneading, and is provided separately from the above-described throttle unit.

With such a configuration, even when defoaming is performed by the defoaming means, the degree of kneading can be adjusted by operating the gate device for adjusting the degree of kneading in parallel with the defoaming. Can be.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 to 4 show a twin-screw kneader 1 according to a first embodiment of the present invention. The twin-screw kneader 1 has a chamber of an apparatus body 5 having a material inlet 2 and a material outlet 3. 6, two rotors 7 are rotatably provided in parallel with each other so as to pass between the ports 2 and 3.

A feed wing 10 having a screw shape (see FIG. 2) is provided in the axial direction of each rotor 7 near the material input port 2, and subsequently, a kneading wing having a cross-sectional shape close to a triangular shape. 11 (see FIG. 3), and then a discharge-side feed blade 12 is provided from the downstream end of the kneading blade 11 to the material outlet 3. The discharge-side feed blade section 12 also has a screw shape similarly to the feed blade section 10 described above.

The chamber 6 of the apparatus body 5 has a gourd-shaped cross section so as to surround each rotor 7 with a uniform gap. The bearing 1 supporting both ends of the rotor 7
The shafts 4 and 15 are of course able to prevent leakage of the kneaded material and the like, but adopt a shaft sealing structure having airtightness.
The apparatus main body 5 is provided with a vent port 18 corresponding to a halfway portion of the discharge-side feed blade section 12 of the rotor 7. The vent port 18 allows the inside of the champer 6 to be evacuated. A defoaming means 19 is provided.

The vent port 18 can be used when a filler or an additive is appropriately mixed into the kneaded material in the chamber 6. The device main body 5 is provided with a throttle portion slightly upstream of the vent port 18 (where the defoaming means 19 is disposed) and corresponding to a halfway portion of the discharge-side feed blade portion 12 of the rotor 7. 21 are provided. As shown in FIG. 4, the throttle unit 21 has a circular section 23 provided on the rotor 7, and a gate device 25 having a pair of upper and lower weir pieces 24 provided above and below the circular section 23. Is formed by

The circular cross section 23 of the rotor 7 is provided in such a manner as to break the feed blade lead of the discharge side feed blade portion 12. The diameter of the circular section 23 is
Although not particularly limited, in the illustrated example, the rotors 7 are formed so as to be as large as possible in a range where the circular cross-sections 23 do not contact each other between the adjacent rotors 7.

On the other hand, each of the upper and lower weir pieces 24 in the gate device 25 has a semi-lunar notch 27 corresponding to the outer periphery of the upper half or lower half of each circular cross section 23 in a side-by-side manner. On both sides in the width direction, the upper and lower weir pieces 24 are fitted or abutted with each other, so that the inside of the chamber 6 can be reliably partitioned. The weir pieces 24 are vertically moved toward and away from each other by an elevation drive device 28 driven by hydraulic pressure or a motor. In the state of being closest to each other, a small gap is held between the notch 27 of each weir piece 24 and the circular section 23 of the rotor 7. This gap is such that the kneaded material sent by the discharge-side feed blade section 12 is immediately filled and closed.

In the discharge-side feed blade section 12,
The axial distance from the downstream end of the kneading blade section 11 to the corresponding position where the throttle section 21 is provided can be determined as follows. That is, the gate device 25 in the throttle unit 21
Is operated in the closing direction, and when the defoaming means 19 is operated, the amount of the kneaded material staying upstream of the squeezing section 21 during one defoaming treatment time of the defoaming means 19 is A volume capable of accommodating this is formed between the periphery of the discharge-side feed blade section 12 on the upstream side of the throttle section 21 and the inner peripheral surface of the chamber 6.

In this case, during the defoaming by the defoaming means 19, the kneaded material staying on the upstream side of the squeezing section 21 is formed.
It can be prevented from protruding to one side. Therefore,
There is no risk that the kneaded material will be kneaded more than necessary. In addition, since the above-mentioned amount of staying kneaded materials varies depending on the rotation speed of the rotor 7, the amount of material input, and the like, the axial distance of the above-mentioned discharge-side feed blade section 12 should be formed somewhat larger. It is suitable.

However, the method of determining the length of the discharge-side feed blade section 12 is not limited to the above-described method. For example, the axial distance from the downstream end of the kneading blade section 11 to the corresponding position of the throttle section 21 is determined. And the vent port 18
There is a method of determining that the axial distance to the corresponding position of the (defoaming means 19) is made equal to each other under the condition that the mutual lead angle is constant. According to this determination method, during a predetermined time, the throttle unit 21 starts from the downstream end of the kneading wing unit 11 as a starting point.
And the amount of the kneaded material passing through the vent port 18 starting from the squeezing section 21 becomes the same amount.
The defoaming time by the defoaming means 19 may be determined on the condition that the kneaded material staying upstream of the squeezing section 21 does not protrude to the kneading wing section 11 side.

Next, in the twin-screw kneader 1 having the above structure,
The operation status will be described. Now, the gate device 25 is operated in the closing direction in the throttle unit 21 (the weir pieces 24 are brought close to each other), the rotor 7 is rotated, and the powdery or granular resin material is supplied from the material inlet 2. And so on. The kneaded material sent to the kneading wing portion 11 by the feed wing portion 10 of the rotor 7 receives a large shearing force between the outer peripheral end of the kneading wing portion 11 and the inner surface of the chamber 6 and is melted and kneaded. Then, the kneaded material is sent toward the throttle unit 21 by the discharge-side feed blade unit 11.

In this narrowing portion 21, a small amount of the kneaded material is extruded from a small gap between the weir piece 24 and the circular cross-sectional portion 23 of each rotor 7; Stays upstream of Therefore, when the staying state reaches a certain degree of filling, the gate device 25 is opened. Therefore, the kneaded material is sent toward the material outlet 3 by the discharge-side feed blade 12. After this predetermined time, the gate device 25 is operated in the closing direction again.

At this time, the defoaming means 19 is operated to evacuate the chamber 6 from the vent port 18. Therefore, deaeration is performed on the kneaded material on the downstream side of the throttle unit 21. At this time, the weir piece 2 is
A small gap between the rotor 4 and the circular cross section 23 of each rotor 7 is filled with the kneaded material, and the kneaded material stays upstream of the throttle 21. Therefore, the action of vacuuming by the defoaming means 19 does not reach the material inlet 2 side, so that air is naturally not taken into the chamber 6 from the material inlet 2. Thereby, air is not entrained in the kneaded material, and oxidation deterioration is less likely to occur.

Thereafter, at an appropriate time before the kneaded material remaining on the upstream side of the throttle unit 21 protrudes into the kneading blade unit 11 of the rotor 7, the gate device 25 is opened in the throttle unit 21 and the discharge side feed blade unit is opened. The feeding of the kneaded material by 12 is restarted. FIG. 5 shows a twin-screw kneader 1 according to a second embodiment of the present invention.
The difference between the second embodiment and the first embodiment is that the throttle unit 21 has a circular section 23 provided on the rotor 7 and a circular section 23 from the inner surface of the chamber 6. The point is that it is formed by the weir wall 30 projecting around.

That is, the throttle 21 of the first embodiment is a movable weir formed by the gate device 25, whereas the throttle 21 of the second embodiment is a fixed weir formed by the weir wall 30. is there. Since other configurations are the same,
The same reference numerals are used for those having the same action, and the detailed description is omitted here. In the second embodiment, the throttle unit 2
1 has no moving parts, and thus has the advantage of being extremely simple structurally and requiring no control at all.

FIG. 6 shows a twin-screw kneader 1 according to a third embodiment of the present invention.
In addition to the twin-screw kneader 1 of the embodiment (see FIG. 1),
The difference is that the rotor 7 is provided with the second circular cross section 33 and that a kneading degree adjusting gate device 34 corresponding to the circular cross section 33 is provided. The kneading degree adjusting gate device 34 has the same structure as the gate device 25 provided in the throttle unit 21, and a pair of upper and lower weir pieces 35 are vertically synchronized by a lifting / lowering drive device 36 driven by hydraulic pressure or a motor. To be close to each other or separated from each other.

The second circular section 33 provided on the rotor 7 is provided at the connection boundary between the kneading blade 11 and the discharge-side feed blade 12, that is, at the downstream end of the kneading blade 11. ing. Therefore, when the defoaming is performed by operating the defoaming means 19, the kneaded material is dammed by the squeezing section 21 so that the kneading degree is not affected at all, and when the kneading degree is adjusted, , A dedicated gate device 34
Can be operated. Therefore,
With this configuration, the method of defoaming by the defoaming means 19 and the method of adjusting the kneading degree by the gate device 34 can be performed simultaneously.

FIG. 7 shows a twin-screw kneader 1 according to a fourth embodiment of the present invention.
For the twin-screw kneader 1 (see FIG. 1) shown in the embodiment,
Further, the third embodiment is different from the first embodiment in that a second kneading blade 40 is provided on the downstream side of the discharge-side feed blade 12. With such a configuration, there is an advantage that the strong kneading of the kneaded material can be performed with high efficiency. Further, when a filler or an additive is added to the inside of the chamber 6 from the vent port 18, the mixture and the kneaded material can be further mixed well.

The present invention allows various improvements other than the above embodiments. For example, the rotor 7
The feed wings and the kneading wings may be further connected in multiple layers. Even in such a case, the configuration of the present invention can be applied downstream of each kneading wing. Devices connected upstream of the material inlet 2 and downstream of the material outlet 3 of the device body 5 are not limited at all.

The kneaded material is not limited to a resin material, but can be applied to a rubber material and other various necessary kneading materials. The provision of the circular cross section 23 at the corresponding portion of the rotor 7 in the throttle section 21 is not limited. In the gate devices 25, 34 and the like, the dam pieces 24, 35 may have a structure in which only one of the upper and lower members is movable, and the other is fixed.

Conventionally, as one of the structures for adjusting the degree of kneading, a structure employing a slot structure (a structure for adjusting the clearance between the periphery of the rotor and the inner peripheral surface of the chamber by utilizing the principle of a needle valve) is known. Known (JP-A-61-23)
However, this slot structure can be adopted as the throttle unit 21 of the present invention.

[0034]

As is apparent from the above description, a discharge-side feed blade is provided on the rotor downstream of the kneading blade, and a middle part or a discharge-side feed blade of the apparatus body is provided. A throttle section is provided in a portion corresponding to the downstream end side,
Further, since the defoaming means is provided on the downstream side of the constricted portion, the defoaming by the defoaming means can be performed while preventing the kneading degree of the kneaded material from becoming undesirably high.

In the present invention, if a gate device for adjusting the degree of kneading is provided separately from the squeezing section, the gate device is operated to allow the defoaming by the defoaming means to be performed in parallel. Then, the kneading degree can be adjusted.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a first embodiment of a twin-screw kneader according to the present invention.

FIG. 2 is an enlarged sectional view taken along line AA of FIG.

FIG. 3 is an enlarged sectional view taken along line BB of FIG. 1;

FIG. 4 is an enlarged sectional view taken along line CC of FIG. 1;

FIG. 5 is a side sectional view showing a second embodiment of the twin-screw kneader according to the present invention.

FIG. 6 is a side sectional view showing a third embodiment of a twin-screw kneader according to the present invention.

FIG. 7 is a side sectional view showing a fourth embodiment of a twin-screw kneader according to the present invention.

FIG. 8 is a side sectional view showing a conventional twin-screw kneader.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Biaxial kneader 2 Material input port 3 Material take-out port 5 Main body 6 Chamber 7 Rotor 10 Feed wing part 11 Kneading wing part 12 Discharge side feed wing part 19 Defoaming means 21 Narrow part 23 Circular cross section 24 Weir piece 25 Gate Apparatus 30 Weir wall 33 Circular cross section (for kneading degree adjustment) 34 Gate device (for kneading degree adjustment) 35 Weir piece (for kneading degree adjustment) 40 Second kneading wing part

Claims (5)

[Claims] 1. Material inlet (2) and material outlet (3)
Two rotors (7) are rotatably provided in parallel with each other across the ports (2, 3) in a chamber (6) of an apparatus body (5) having In a twin-screw kneader provided with a feed blade (10) and a kneading blade (11) in the axial direction, the rotor (7) has a discharge-side feed blade (10) downstream of the kneading blade (11). 12) is provided, and the device main body (5) is provided with a restricting portion (21) for retaining the kneaded material sent by the discharge side feed blade portion (12) by restricting the inside of the chamber (6). And a defoaming means (19) for sucking the inside of the chamber (6) downstream of the throttle (21). 2. The gate device (25), wherein the throttle portion (21) is capable of moving a weir piece (24) toward and away from a circular section (23) provided on the rotor (7) and having a rotation axis as a center. 2. The twin-screw kneader according to claim 1, wherein: 3. The weir wall (3) protruding from the inner surface of the chamber (6) around a circular cross-section (23) around the rotation axis provided on the rotor (7). 30. The twin-screw kneader according to claim 1, wherein the kneader is formed by the following method. 4. The circumference of a discharge-side feed blade (12) from the kneading blade (11) of the rotor (7) to the throttle (21) of the apparatus body (5) and the inner peripheral surface of the chamber (6). In the meantime,
4. A volume capable of accommodating an amount of the kneaded material staying in the narrowing portion (21) is secured.
The twin-screw kneader according to any one of the above. 5. A rotor (7) is provided with a circular section (33) centered on the rotation axis at a connection boundary between the kneading blade (11) and the discharge-side feed blade (12); A gate device (34) for adjusting the degree of kneading that allows the weir piece (35) to approach and separate from the circular section (33) around the circular section (33) is provided separately from the throttle section (21). The twin-screw kneader according to any one of claims 1 to 4, wherein: