JP2014113706A - Twin screw strainer extruding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To raise an extruding pressure from a discharge port while securing excellent biting performance to rubber-like material.SOLUTION: A twin screw extruding apparatus main body and a strainer part mounted at its front end are provided. The twin screw extruding apparatus main body includes a pair of taper screw shafts arranged as inclined so that the front ends approach each other. The taper screw shafts are divided into a one screw part in a hopper area side in which one screw blade rotates spirally round a rotor shaft and a multi screw part in a feed area side in which plural screw blades rotate spirally.

Description

  The present invention relates to a twin-screw strainer extrusion apparatus that can increase the extrusion pressure from a discharge port while ensuring the biting property to a rubber-like material charged from the input port, and enables the installation of a strainer network.

  When a rubber product is formed using an extruder, it is necessary to continuously and stably supply a rubber-like material to the extruder. Therefore, for example, as conceptually shown in FIG. 4, a massive rubber-like material G kneaded by a closed mixer a such as a kneader is formed into a continuous long sheet using a roller head extruder b. To do. Thereafter, the rubber-like material G1 in the form of a long sheet is supplied directly or indirectly to the extrusion molding machine c to mold a rubber product.

  On the other hand, as the roller head extruder b, a biaxial taper extruder d having a roller head attached to the front end side is frequently used (see, for example, Patent Document 1). As shown in FIGS. 5A and 5B, the biaxial taper extruder d includes a pair of tapered screw shafts e and e supported in an inclined state in which the front ends approach each other. Therefore, even when the rubber-like material G introduced from the insertion port f forms a large lump, it can be taken in between the tapered screw shafts e and e as it is. However, on the other hand, the back flow from the gap between the screw blade e1 and the inner wall surface of the cylinder hole h and the gap between the tapered screw shafts e and e is inevitably large, so that the rubber-like material G is extruded from the discharge port i. The pressure is not high enough.

  Therefore, when a strainer net is attached to the front end of the biaxial taper extruder d in order to remove dust, impurities, etc. mixed in the rubber-like material G, the extrusion pressure is insufficient and the necessary extrusion amount is stabilized. The problem that it cannot be obtained arises.

  Therefore, conventionally, when the rubber-like material is strained, a single screw extruder is used instead of the twin screw taper d. However, the single-screw extruder has a high extrusion pressure from the discharge port, but has a single screw shaft, and therefore is inferior in the biting performance to the rubber-like material G to be charged. Therefore, when the rubber-like material G forms a large lump, it is necessary to separately provide a pressure device (for example, a hydraulic pusher device) for pressing the lump-like rubber-like material G to be charged toward the screw shaft. There is a problem that it causes a significant increase in cost.

JP 2006-305976 A

  The present invention has been made in view of the above circumstances, and is based on the fact that the taper screw shaft is composed of a single-thread screw portion on the hopper region side and a multi-thread screw portion on the feed region side. To provide a twin-screw strainer extrusion device that can sufficiently increase the extrusion pressure from the discharge port while ensuring the excellent biting property of a taper extruder and can perform straining while suppressing an increase in device cost. It is an object.

In order to solve the above-mentioned problems, the invention of claim 1 of the present application relates to a twin-screw extruder main body that continuously extrudes from the discharge port at the tip while kneading the rubber-like material charged from the input port, A biaxial strainer extrusion device comprising a strainer section having a strainer net for removing foreign matters in the rubber-like material attached to the front,
The biaxial extruder body is:
A casing having a cylinder hole communicating with the charging port and the discharging port, and the cylinder hole being divided into a hopper region on the rear side and a feed region on the front side of the front edge of the charging port;
And having a taper shape in which the outer diameter gradually decreases toward the front end, and having a pair of taper screw shafts rotatably arranged in the cylinder hole in an inclined state in which the front ends approach each other,
Each of the tapered screw shafts includes a single screw portion on the hopper region side where one screw blade is spirally wound around the rotor shaft, and a feed region side where a plurality of screw blades are spirally wound. It is characterized by being divided into multi-threaded screw parts.

  According to a second aspect of the present invention, the axial length of the single screw portion is in the range of 85 to 100% of the axial width of the hopper region.

  According to a third aspect of the present invention, one screw blade forming the single screw portion and one of the plurality of screw blades forming the multi-thread screw portion are integrally connected.

  According to a fourth aspect of the present invention, the lead length of the screw blade gradually decreases toward the front end side.

  According to a fifth aspect of the present invention, the screw blade is characterized in that the protruding height from the rotor shaft gradually decreases toward the front end side.

  According to a sixth aspect of the present invention, the pair of tapered screw shafts are characterized in that the winding directions of the screw blades are opposite to each other and are driven to rotate in opposite directions.

  According to a seventh aspect of the present invention, a roller head having upper and lower calendar rolls is attached to the front end side of the biaxial extruder main body via the strainer portion.

  As described above, the main body of the twin screw extruder used in the present invention has a pair of tapered screw shafts arranged in an inclined state in which the front ends thereof are close to each other in the casing. In addition, the taper screw shaft is divided into a single screw portion on the hopper region side with one screw blade and a multiple screw portion on the feed region side with a plurality of screw blades.

  Therefore, it is possible to exhibit high biting performance by providing two tapered screw shafts in the inclined state and by forming each taper screw shaft as a single screw on the hopper region side. As a result, even when the rubber-like material charged from the charging port forms a large lump, it can be taken in as it is between the tapered screw shafts without using a hydraulic pusher device or the like.

  Further, in the taper screw shaft, since the feed region side is a multi-thread screw, the extrusion pressure from the discharge port can be sufficiently increased. For this reason, it is possible to perform straining by providing a strainer net on the front end side of the main body of the twin screw extruder without causing a shortage of rubber extrusion amount.

It is sectional drawing from the side part side which shows one Example of the biaxial strainer extrusion apparatus of this invention. It is sectional drawing from the upper side. (A), (B) is sectional drawing which shows the sectional view shape of a cylinder hole. It is a conceptual diagram explaining the formation method of the rubber product using an extrusion molding machine. (A) is sectional drawing from the side part side of the conventional biaxial taper extruder, (B) is sectional drawing from the upper side.

Hereinafter, embodiments of the present invention will be described in detail.
As shown in FIGS. 1 and 2, the biaxial strainer extrusion apparatus 1 of the present embodiment is a biaxial extrusion that continuously extrudes from the discharge port 3 at the tip while kneading the rubber-like material G introduced from the injection port 2. A machine main body 4 and a strainer portion 5 attached to the front side of the discharge port 3 are provided.

  In this example, the roller head 6 is attached to the front end side of the strainer portion 5 and the rubber-like material G from the discharge port 3 is formed into a long sheet-like body G1 continuous in the length direction. It is. Such a biaxial strainer extruding apparatus 1 forms a massive rubber-like material G received intermittently from a closed mixer such as a kneader into a long sheet-like body G1 that is continuous in the length direction. Used to supply continuously and stably to a rubber extruder.

  The biaxial extruder body 4 includes a casing 9 having a cylinder hole 8 extending in the front-rear direction, a pair of taper screw shafts 10 disposed in the cylinder hole 8, and each taper screw attached to the rear end of the casing 9. And a driving means 11 for rotationally driving the shaft 10.

  The opening of the cylinder hole 8 on the front end side forms the discharge port 3. The charging port 2 opens upward on the upper surface of the casing 9, and the charging port 2 is electrically connected to the cylinder hole 8 on the rear end side. The cylinder hole 8 is divided into a hopper area YA on the rear side of the front edge 2E of the charging port 2 and a feed area YB on the front side of the front edge 2E.

  3A and 3B show cross-sectional shapes of the cylinder holes 8 in the hopper region YA and the feed region YB. As shown in the figure, in the feed region YB, the cylinder hole 8 has a bowl-shaped cross section in which tapered holes 8a, 8a concentric with the tapered screw shafts 10 are partially overlapped. Further, in the hopper area YA, in this example, the upper half of the bowl shape is formed as a half bowl shape with the inlet 2 removed. A cylindrical hopper 12 that rises from the upper surface of the casing 9 and guides the rubber-like material G into the charging port 2 while temporarily storing it is provided around the charging port 2.

  As shown in FIG. 2, each of the tapered screw shafts 10 has a tapered shape whose outer diameter gradually decreases toward the front end. The tapered screw shaft 10 is horizontally accommodated in the cylinder hole 8 in an inclined state in which the front ends thereof approach each other.

  Each of the tapered screw shafts 10 is formed of a rotor shaft 14 and screw blades 15 that are spirally wound around the rotor shaft 14. The rotor shaft 14 includes a rotor shaft main body 14M extending in the cylinder hole 8 and a projecting portion 14E projecting rearward beyond the cylinder hole 8. The projecting portion 14E allows the taper screw shaft 10 to be cantilevered. And is supported rotatably. The projecting portion 14E is connected to known driving means 11 including a motor, a reduction gear, and the like, and is driven to rotate.

  In this example, the winding direction of the screw blade 15 on one taper screw shaft 10 is opposite to the winding direction of the screw blade 15 on the other taper screw shaft 10, and one taper screw shaft 10 on the other side. Are driven to rotate in opposite directions. Further, the screw blade 15 in one taper screw shaft 10 enters the pitch circle of the screw blade 15 in the other taper screw shaft 10.

  The taper screw shaft 10 includes a single screw portion 10A on the hopper region YA side in which one screw blade 15 is spirally wound around the rotor shaft main body 14M, and a plurality of screw blades 15 are formed on the rotor shaft main body. It is divided into a multi-thread screw portion 10B on the feed region YB side that is spirally wound around 14M. In this example, the case where the multi-threaded screw part 10B is a two-threaded screw part 10Ba in which two screw blades 15 are arranged is shown. In the multi-thread screw portion 10B, the plurality of screw blades 15 are arranged at equal pitch intervals.

  In the tapered screw shaft 10, one screw blade 15 forming the single screw portion 10A and one of the plurality of screw blades 15 forming the multi-thread screw portion 10B are integrally connected. . In other words, the screw blade 15 spirals on the feed region YB side through the main screw blade 15a continuously extending spirally over the substantially entire length of the rotor shaft main body 14M and the lead of the main screw blade 15a. It is comprised from the subscrew blade | wing 15b extended in the shape. Accordingly, the single screw portion 10A is formed by the main screw blade 15a, and the multiple screw portion 10B (in this example, the double screw portion 10Ba) is formed by the main screw blade 15a and the sub screw blade 15b. .

  Thus, the biaxial extruder body 4 includes a pair of tapered screw shafts 10 in the inclined state, and the tapered screw shaft 10 forms a single screw portion 10A on the hopper region YA side. As with the biaxial taper extruder, high biting performance can be exhibited. Therefore, even when the charged rubbery material G forms a large lump, it can be taken in between the taper screw shafts 10 and 10 as it is.

  The tapered screw shaft 10 forms a multi-threaded screw portion 10B on the feed region YB side. Therefore, the extrusion pressure from the discharge port 3 can be sufficiently increased. As a result, it is possible to perform straining by providing the strainer portion 5 on the front end side of the twin-screw extruder body 4 without causing a shortage of rubber extrusion amount.

  Particularly in this example, the lead length of the screw blade 15 is gradually reduced toward the front end side. Further, the protruding height H of the screw blade 15 from the rotor shaft 14 is gradually reduced toward the front end side. That is, on the hopper area YA side, the lead length is large and the protrusion height H is high. Therefore, the biting performance can be further improved. Further, as described above, the winding directions of the screw blades 15 on the one and the other taper screw shafts 10 are opposite to each other and are driven to rotate in opposite directions, respectively, so that the biting performance into the rubber-like material G, and The extrusion pressure from the discharge port 3 can be further increased.

  In order to increase the extrusion pressure while ensuring the biting performance, the axial length LA of the single screw portion 10A is in the range of 85 to 100% of the axial width W of the hopper region YA. Preferably there is. When the length LA is less than 85% of the width W, the single screw portion 10A becomes too small, and the biting performance decreases. The length LA and the width W are values measured on the axial line of the taper screw shaft 10 when viewed from above, as shown in FIG.

  Next, as shown in FIG. 1, the strainer portion 5 includes a strainer net 5a for removing dust, impurities and the like mixed in the rubber-like material G, and a support frame 5b for holding the strainer net 5a. With. The strainer portion 5 is replaceably attached to the front end portion of the biaxial extruder body 4.

  The roller head 6 includes upper and lower calendar rolls 20U, 20L and a support frame 21 that pivotally supports the calendar rolls 20U, 20L. A well-known driving means (not shown) for rotating and driving the calendar rolls 20U, 20L is attached to the support frame 21, and the width of the long sheet-like body G1 is regulated between the calendar rolls 20U, 20L. Side guides 21 (shown in FIG. 2) are arranged.

  As mentioned above, although especially preferable embodiment of this invention was explained in full detail, this invention is not limited to embodiment of illustration, It can deform | transform and implement in a various aspect.

  In order to confirm the effect of the present invention, a biaxial strainer extrusion device having the structure shown in FIGS. Then, when the rubber-like material kneaded by a kneader (closed mixer) was added, the biting property into the rubber-like material and the extrusion performance from the discharge port were tested and compared with each other. The specifications are substantially the same except for the number of screw blades on the taper screw shaft. For comparison, the same test was performed using a single screw extruder.

(1) Biting property:
The biting property when a massive rubber-like material was charged was evaluated by a three-point method. Larger numbers are better.

(2) Extrusion performance:
The amount of rubber-like material extruded through a strainer network and its stability were evaluated by a three-point method. Larger numbers are better.

  As shown in the table, it can be confirmed that the embodiment can increase the extrusion pressure from the discharge port while ensuring excellent biting into the rubber-like material, and can stably perform the training.

DESCRIPTION OF SYMBOLS 1 2 axis | shaft strainer extrusion apparatus 2 Input port 3 Discharge port 4 2 axis | shaft extruder main body 5 Strainer part 5a Strainer net | network 6 Roller head 8 Cylinder hole 9 Casing 10 Tapered screw shaft 10A1 Thread part 10B Multiple thread | screw part 12 Shaft strainer extrusion apparatus 14 Rotor shaft 15 Screw blade 20U, 20L Calendar roll G Rubber material YA Hopper area YB Feed area

Claims (7)

A twin-screw extruder main body that continuously extrudes from the discharge port at the tip while kneading the rubber-like material charged from the input port, and a strainer network that removes foreign matter in the rubber-like material attached to the front of the discharge port A twin-screw strainer extrusion device comprising a strainer section,
The biaxial extruder body is:
A casing having a cylinder hole communicating with the charging port and the discharging port, and the cylinder hole being divided into a hopper region on the rear side and a feed region on the front side of the front edge of the charging port;
And having a taper shape in which the outer diameter gradually decreases toward the front end, and having a pair of taper screw shafts rotatably arranged in the cylinder hole in an inclined state in which the front ends approach each other,
Each of the tapered screw shafts includes a single screw portion on the hopper region side where one screw blade is spirally wound around the rotor shaft, and a feed region side where a plurality of screw blades are spirally wound. A twin-screw strainer extrusion device characterized by being divided into a multi-thread screw portion.   2. The twin-screw strainer extrusion apparatus according to claim 1, wherein a length of the single screw portion in an axial direction is in a range of 85 to 100% of an axial width of the hopper region.   The one screw blade forming the single screw portion and one of the plurality of screw blades forming the multiple screw portion are integrally connected. Axis strainer extrusion equipment.   The twin screw strainer extrusion device according to any one of claims 1 to 3, wherein a lead length of the screw blade gradually decreases toward a front end side.   The twin-screw strainer extrusion device according to any one of claims 1 to 4, wherein the screw blades have a projecting height from the rotor shaft that gradually decreases toward the front end side.   The twin-screw strainer extrusion according to any one of claims 1 to 5, wherein the pair of taper screw shafts have screw blades wound in opposite directions and are driven to rotate in opposite directions. apparatus. The twin-screw strainer extrusion apparatus according to any one of claims 1 to 6, wherein a roller head having upper and lower calendar rolls is attached to the front end side of the two-screw extruder main body via the strainer portion. .

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