JP2018062078A - Method and apparatus for manufacturing rubber extrusion object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for manufacturing a rubber extrusion object capable of suppressing curvature of the rubber extrusion object while suppressing variation in a boundary surface of rubber-to-rubber, when a plurality of unvulcanized rubbers are extruded from one extrusion port to integrate them.SOLUTION: A flow regulating plate 8 of a rigid body with which unvulcanized rubbers r1 and r2 supplied from cylinders 2A and 2B, respectively are completely isolated to each other is extended in an extruding direction and fixed to one die 5 in which one extrusion port 6 is formed; a front end 8a of the flow regulating plate 8 is set to a position 1 mm or more retreated from a front face of the extrusion port 6; and the unvulcanized rubbers r1 and r2 are guided forward through a first flow channel 7A and a second flow channel 7B, respectively, in a state where the unvulcanized rubbers r1 and r2 are completely separated from each other in the region where the flow regulating plate 8 of the die 5 is present, by setting flow rates at the die 5 of the unvulcanized rubbers r1 and r2 to nearly the same level, to acquire a rubber extrusion object R in which the unvulcanized rubbers r1 and r2 are integrated in a region in front of the flow regulating plate 8.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a method and an apparatus for producing a rubber extrudate, and more specifically, when a plurality of unvulcanized rubbers are extruded from a single extrusion port and integrated, they are extruded while suppressing fluctuations in the interface between rubbers. The present invention relates to a method and an apparatus for producing a rubber extrudate capable of suppressing the curvature of the rubber extrudate.

  When manufacturing rubber products such as tires, there is an extrusion process in which unvulcanized rubber is extruded by a rubber extrusion device. In a rubber extrusion device, so-called multicolor rubber extrusion is sometimes performed in which a plurality of unvulcanized rubbers are extruded from one extrusion port and integrated (for example, see Patent Document 1).

  In multi-color rubber extrusion, due to the difference in flow rate immediately before the extrusion port of each unvulcanized rubber to be sent out, the rubber extrudate extruded from the extrusion port is curved by integrating each unvulcanized rubber. There is. In order to suppress the curvature of this rubber extrudate, adjusting the rotational speed (extrusion speed) of the screw that sends out the unvulcanized rubber, and reducing the flow rate difference between the unvulcanized rubber, integrated unvulcanized rubber The interface between the two fluctuates. As a result, the shape of the rubber extrudate may not be obtained as set.

JP 2015-47838 A

  The object of the present invention is to suppress the curvature of the extruded rubber extrudate while suppressing the fluctuation of the boundary surface between the rubbers when a plurality of unvulcanized rubbers are extruded and integrated from one extrusion port. The object is to provide a method and apparatus for producing extrudates.

  In order to achieve the above object, a method for producing a rubber extrudate according to the present invention includes a rubber extrudate producing method for producing a rubber extrudate obtained by integrating a plurality of unvulcanized rubbers by extruding them from one extrusion port. A rigid rectifying plate that completely separates the unvulcanized rubber from each other is fixed to one die having an extrusion port extending in the extrusion direction, and the front end of the rectifying plate is fixed to the front end of the extrusion port. Set at a position retracted by 1 mm or more from the surface, set the flow rate of each unvulcanized rubber at the die to the same level, and in the region where the current plate of the die exists, The vulcanized rubber is guided forward in a state of being completely separated from each other, and the respective unvulcanized rubbers are integrated in a region in front of the current plate.

  The rubber extrudate manufacturing apparatus of the present invention is provided with a plurality of cylindrical cylinders with screws, one head installed at the tip of the plurality of cylinders, and a tip of the one head. And a die having a single extrusion port, and a structure for producing a rubber extrudate in which a plurality of unvulcanized rubber supplied from each of the plurality of cylinders is extruded and integrated from the one extrusion port. In the rubber extrudate manufacturing apparatus, a rigid baffle plate extending in the extruding direction of the rubber extrudate and fixed to the one die and completely isolating the unvulcanized rubber from each other, The front end of the rectifying plate is set at a position retracted by 1 mm or more from the front end surface of the extrusion port, the flow rate of each unvulcanized rubber at the die is set to be approximately the same, and the rectifying plate of the die is In the existing area The unvulcanized rubber is guided forward in a state where the unvulcanized rubber is completely separated from each other, and the unvulcanized rubber is integrated in a region in front of the current plate. .

  According to the present invention, a rigid rectifying plate that completely separates each unvulcanized rubber from each other is fixed to one die having one extrusion port extending in the extrusion direction, and the rectification is performed. The front end of the plate is set at a position retracted by 1 mm or more from the front end surface of the extrusion port. Thereby, in the area | region where the said baffle plate of the said die | dye exists, each said unvulcanized rubber can be guide | induced ahead in the state isolate | separated completely from each other. Therefore, the opposing surfaces of the respective unvulcanized rubbers are in a constant state along the current plate until just before joining each other. Accordingly, even if the flow rates of the respective unvulcanized rubbers are adjusted to the same level, fluctuations in the boundary surfaces of the respective unvulcanized rubbers when integrated rubber extrudates can be suppressed. Further, by adjusting the flow rates of the respective unvulcanized rubbers to the same extent, it is possible to avoid the problem that the integrated rubber extrudate is curved. Furthermore, by setting the front end of the current plate at a position retracted by 1 mm or more from the front end surface of the extrusion port, the unvulcanized rubber can be firmly integrated in the front region of the current plate. it can.

It is explanatory drawing which illustrates the cross-sectional structure of the rubber extrusion apparatus of this invention by a side view. It is explanatory drawing which illustrates die | dye of FIG. 1 by front view. FIG. 2 is an enlarged view around a die and a head in FIG. 1. It is explanatory drawing which illustrates the state in which each unvulcanized rubber is integrated by the rubber extrusion apparatus of FIG. It is explanatory drawing which illustrates the modification of a baffle plate by a longitudinal cross-sectional view.

  Hereinafter, the rubber extrusion product manufacturing method and manufacturing apparatus of the present invention will be described based on the embodiments shown in the drawings.

  The rubber extrudate manufacturing apparatus 1 of the present invention illustrated in FIGS. 1 to 3 includes a plurality of cylindrical cylinders 2A and 2B, and a single head 4 installed at the ends of the plurality of cylinders 2A and 2B. This is a so-called multicolor rubber extruding apparatus provided with a die 5 disposed at the tip of one head 4 and having one extrusion port 6. Each of the cylinders 2A and 2B is internally provided with screws 3A and 3B for supplying unvulcanized rubbers r1 and r2 kneaded inside toward the head 4. The manufacturing apparatus 1 is further provided with a die 5 having a rigid current plate 8. A take-up conveyor 9 is disposed in front of the extrusion port 6.

  A plurality of unvulcanized rubbers r1 and r2 supplied from the respective cylinders 2A and 2B by the rotating screws 3A and 3B are extruded from one extrusion port 6 to be an integrated rubber extrudate R. The rubber extrudate R is taken out by the take-out conveyor 9 while being extruded from the extrusion port 6 and conveyed to the next process.

  The current plate 8 is disposed in the vicinity of the extrusion port 6, extends in the extrusion direction of the rubber extrudate R, and is fixed to the die 5. The rectifying plate 8 is a rigid body that completely separates the unvulcanized rubbers r1 and r2 supplied from the cylinders 2A and 2B from each other, and is made of a metal such as a steel plate, for example.

  The front end 8 a of the current plate 8 is set at a position retracted by 1 mm or more from the front end surface of the extrusion port 6. That is, a straightening plate 8 having an extension length b extending from the front end face of the extrusion port 6 to the rear from the position of the predetermined dimension a is installed, and the predetermined dimension a is set to 1 mm or more. Yes. Due to the presence of the current plate 8, the die 5 is formed with a first flow path 7A through which one unvulcanized rubber r1 flows and a second flow path 7B through which the other unvulcanized rubber r2 flows.

  The upper limit value of the predetermined dimension a is set in a range where the rectifying plate 8 is in the vicinity of the extrusion port 6 and is, for example, about 30 mm. The extension length b is set to 10 mm or more, for example. The upper limit value of the extension length b is, for example, about 100 mm, but is not limited to this.

  The thickness of the current plate 8 is set to 0.5 mm or more so as not to be easily deformed by the pressure of the flowing unvulcanized rubbers r1 and r2. In order to reliably suppress the deformation of the rectifying plate 8, the thickness is preferably 2 mm or more. On the other hand, if the thickness of the current plate 8 is excessive, it becomes difficult to integrate the unvulcanized rubbers r1 and r2, so that the thickness is set to 3 mm or less, for example.

  In this embodiment, the upper part of the rectifying plate 8 of the extrusion port 6 is smaller than the lower part of the rectifying plate 8 and is unevenly distributed on one side in the width direction. The opening shape of the extrusion port 6 is not limited to the shape shown in this embodiment, and other shapes are also employed. For example, the upper part and the lower part of the current plate 8 of the extrusion port 6 may have the same shape. Moreover, it is not limited to the specification which provides two cylinder 2A, 2B like this embodiment, Three or more cylinders can also be provided. Also in that case, the arrangement and specifications of the current plate 8 are as described above.

  Next, the procedure for producing the rubber extrudate R using the method for producing a rubber extrudate of the present invention will be described.

  In order to extrude the rubber extrudate R by the rubber extruding device 1, a predetermined amount of unvulcanized raw rubber and compounding agent are introduced into the respective cylinders 2A and 2B. The charged materials are mixed and kneaded by rotating screws 3A and 3B. Each of the unvulcanized rubbers r1 and r2 mixed and kneaded is softened to some extent (plasticized) and shaped into a cross-sectional shape from the extrusion port 6 to the extrusion port 6 to obtain an unvulcanized rubber extrudate R. Extruded into a sheet. Each of the unvulcanized rubbers r1 and r2 may be of the same type (same rubber physical properties) or different types (different rubber physical properties).

  At this time, each unvulcanized rubber r1, r2 fed forward by each screw 3A, 3B4 is one head 4 and die 5 attached to one head 4, as illustrated in FIG. To be aggregated. In the region where the rectifying plate 8 of the die 5 exists, the respective unvulcanized rubbers r1 and r2 are completely separated from each other by the rectifying plate 8 and guided forward. Therefore, the opposing surfaces of the respective unvulcanized rubbers r1 and r2 flow along the rectifying plate 8 until just before being joined to each other, so that they are formed in a constant state.

  The unvulcanized rubbers r <b> 1 and r <b> 2 are integrally joined by opposing surfaces naturally joined in the flow forward in the region ahead of the current plate 8. That is, due to the swell of the unvulcanized rubbers r1 and r2 completely separated by the current plate 8, the opposed surfaces of the rubber extrudate R are automatically joined in the front region of the current plate 8. To do.

  When the flow rate difference between the unvulcanized rubbers r1 and r2 in the die 5 is large, the flow rate of at least one unvulcanized rubber R1 (r2) is adjusted so that the flow rates are approximately the same (for example, the flow rates are the same or The flow rate difference between each flow rate is within 3%). Even if the flow rates of the unvulcanized rubbers r1 and r2 are adjusted in this way, when the two are joined, each opposing surface is in a constant state along the current plate 8, so that the integrated rubber extrudate The fluctuation of the boundary surface M (opposing surface) of each of the unvulcanized rubbers r1 and r2 when R is reached can be suppressed. When the flow rate difference between the dies 5 of the unvulcanized rubbers r1 and r2 is small, it is not necessary to adjust the flow rates of the unvulcanized rubbers r1 and r2.

  And the malfunction which the integrated rubber extrudate R curves can be avoided by making the flow velocity of each unvulcanized rubber r1 and r2 comparable. That is, it is possible to suppress the curvature of the rubber extrudate R generated due to the difference in flow rate between the unvulcanized rubbers r1 and r2. Furthermore, by setting the front end 8a of the current plate 8 to a position retracted by 1 mm or more from the front end surface of the extrusion port 6, the unvulcanized rubbers r1 and r2 are separated from each other in the region ahead of the current plate 8. It can be firmly integrated without leaving.

  If the predetermined dimension a is less than 1 mm, there is a high possibility that the rubber extrudate R remains separated by the rectifying plate 8, which hinders use in subsequent processes. Therefore, in the present invention, by setting the predetermined dimension a to 1 mm or more, the opposing surfaces of the respective unvulcanized rubbers r1 and r2 are easily joined to each other. When the opposing surfaces are joined to each other, the opposing surfaces disappear and become a close boundary surface M, which is conveyed to the next process by the take-up conveyor 9. Therefore, the rubber extrudate R can be used as it is sent to the next process of the production line. If the predetermined dimension a is excessively large, the effect of suppressing the fluctuation of the boundary surface M between the respective unvulcanized rubbers r1 and r2 is lost. Therefore, the predetermined dimension a is preferably set to 1 mm to 30 mm, for example.

  When the extending length b of the rectifying plate 8 is 10 mm or more, the unvulcanized rubbers r1 and r2 contacting the surface of the rectifying plate 8 can be sufficiently equalized. Therefore, it is advantageous to suppress the fluctuation of the boundary surface M of the rubber extrudate R. A suitable extension length b is, for example, 10 mm or more and 70 mm or less.

  The front end portion of the rectifying plate 8 is not limited to the shape exemplified in this embodiment, and other shapes can be adopted. As illustrated in FIG. 5A, one surface of the front end can be inclined, or both surfaces of the front end can be inclined as illustrated in FIG. As illustrated in FIGS. 5A and 5B, when the front end portion of the current plate 8 becomes thinner toward the front, the unvulcanized rubbers r1 and r2 are easily integrated smoothly.

DESCRIPTION OF SYMBOLS 1 Extruder 2A, 2B Cylinder 3A, 3B Screw 4 Head 5 Die 6 Extrusion port 7A 1st flow path 7B 2nd flow path 8 Current plate 8a Front end 9 Take-out conveyor r1, r2 Unvulcanized rubber R Rubber extrudate M Boundary surface

Claims (7)

In a method for producing a rubber extrudate for producing a rubber extrudate in which a plurality of unvulcanized rubbers are extruded and integrated through a single extrusion port,
A rigid rectifying plate that completely separates the unvulcanized rubber from each other is fixed to one die formed with the extrusion port by extending in the extrusion direction, and the front end of the rectifying plate is fixed to the extrusion port. It is set at a position retracted by 1 mm or more from the front end surface, the flow rate of each unvulcanized rubber at the die is set to the same level, and the unadjusted plate in the region where the current plate of the die exists. A method for producing a rubber extrudate, wherein the vulcanized rubber is guided forward in a state of being completely separated from each other, and the respective unvulcanized rubbers are integrated in a region in front of the current plate.   The manufacturing method of the rubber extrudate of Claim 1 which sets the front end of the said baffle plate in the range within 30 mm back from the front-end surface of the said extrusion port. A plurality of cylindrical cylinders in which screws are installed, one head installed at the tip of the plurality of cylinders, and a die having one extrusion port disposed at the tip of the one head A rubber extrudate manufacturing apparatus configured to manufacture a rubber extrudate in which a plurality of unvulcanized rubber supplied from each of the plurality of cylinders is extruded and integrated from the one extrusion port,
A rigid baffle plate extending in the extrusion direction of the rubber extrudate and fixed to the one die, and completely isolating the unvulcanized rubber from each other, the front end of the baffle plate being the extrusion port; Is set at a position retracted by 1 mm or more from the front end surface, the flow rate of each unvulcanized rubber at the die is set to the same level, and in the region where the current plate of the die is present, A rubber extrudate in which unvulcanized rubber is guided forward in a state of being completely separated from each other, and the respective unvulcanized rubber is integrated in a region in front of the current plate. Manufacturing equipment.   The apparatus for producing a rubber extrudate according to claim 3, wherein a front end of the current plate is set in a range within 30 mm rearward from a front end surface of the extrusion port.   The apparatus for producing a rubber extrudate according to claim 3 or 4, wherein the current plate has a thickness of 0.5 mm or more and 3 mm or less.   The apparatus for producing a rubber extrudate according to any one of claims 3 to 5, wherein an extension length of the current plate is 10 mm or more.   The apparatus for producing a rubber extrudate according to any one of claims 3 to 6, wherein a front end portion of the current plate is tapered toward the front.

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