JP2015071276A - Method of measuring temperature of rubber extrusion and temperature measurement unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of measuring the temperature of a rubber extrusion and a temperature measurement unit which enable measurement of the internal temperature of a rubber extrusion immediately after extrusion from an extruder, with high accuracy compared with conventional methods.SOLUTION: A method of measuring the temperature of a rubber extrusion comprises fixing a metal wire 2 of a wire diameter of 0.2-0.5 mm to a die 8 and tightening in the front surface of an extrusion port 9 of the die 8 arranged in an extruder 7, extruding a rubber extrusion R from the extrusion port 9, cutting the rubber extrusion R with the metal wire 2 while regulating the deflection of the metal wire 2 pressed by the rubber extrusion R by a regulation member 4 attached close to the extrusion port 9, and measuring the temperature of the cut surface Rf of the extrusion R immediately after cutting by a non-contact type temperature measurement instrument 6.

Description

  The present invention relates to a temperature measurement method and a temperature measurement unit for rubber extrudates. More specifically, the internal temperature of a rubber extrudate immediately after being extruded from an extruder can be measured with higher accuracy than in the past. The present invention relates to a temperature measurement method and a temperature measurement unit for rubber extrudates.

  When manufacturing rubber products such as tires, there is an extrusion process in which unvulcanized rubber is extruded by an extruder. In such an extrusion process, the unvulcanized rubber is extruded from an extrusion port of a die attached to the extruder, thereby forming a rubber extrudate molded into a predetermined shape. Here, for example, when unvulcanized rubber compounded with silica is extruded, the internal temperature of the rubber extrudate has a great influence on the stability of the rubber extrudate, for example, the inside of the rubber extrudate foams due to a temperature rise due to plasticization. It is important to accurately grasp the internal temperature of the rubber extrudate because local deformation of the rubber extrudate generated when plasticized by the screw of the extruder appears in the internal temperature distribution of the rubber extrudate. .

  Various methods for measuring the internal temperature of the rubber extrudate have been proposed (see, for example, Patent Document 1). In the measuring method proposed in Patent Document 1, the surface temperature of the rubber extrudate is measured at at least two locations, and the internal temperature of the rubber extrudate is determined based on the measured value and the thickness of the rubber extrudate. However, this method does not actually measure the internal temperature of the rubber extrudate, but predicts it, so there is a limit to increasing the measurement accuracy.

  In the method of directly measuring the internal temperature by inserting a thermometer probe directly into a rubber extrudate immediately after extrusion, the probe temperature affects the measurement temperature. It is necessary to take measures such as heating up to the temperature. Alternatively, it is also conceivable that the rubber extrudate immediately after extrusion is cut with a cutting tool such as a blade and the cut surface is measured with an infrared thermometer or the like. However, since the cutting tool such as a blade has a large contact area with the rubber extrudate (the contact time is long), the temperature difference between the rubber extrudate and the cutting tool affects the measurement temperature, and the temperature of the cut surface changes. Therefore, there is a problem that the internal temperature of the rubber extrudate (the temperature of the cut surface) cannot be accurately measured.

JP-A-11-151747

  An object of the present invention is to provide a temperature measurement method and a temperature measurement unit for a rubber extrudate, which can measure the internal temperature of a rubber extrudate immediately after being extruded from an extruder with higher accuracy than in the past. It is in.

  In order to achieve the above object, the rubber extrudate temperature measuring method of the present invention is to fix a metal wire having a wire diameter of 0.2 mm or more and 0.5 mm or less to a die installed in an extruder, and Tension is applied to the front surface, an unvulcanized rubber extrudate is extruded from the extrusion port, and the metal wire pressed by the rubber extrudate is controlled while being regulated by a regulating member attached in the vicinity of the extrusion port. The rubber extrudate thus cut is cut with the metal wire, and the temperature of the cut surface of the rubber extrudate immediately after the cutting is measured by a non-contact temperature measuring device.

  The rubber extrudate temperature measuring unit of the present invention comprises a metal wire having a wire diameter of 0.2 mm or more and 0.5 mm or less disposed in front of a die extrusion port installed in an extruder, and the metal wire as the die. A fixing means for fixing and tensioning, a regulating member that is installed in the vicinity of the extrusion port and regulates the deflection of the metal wire due to an unvulcanized rubber extrudate extruded from the extrusion port, and is extruded from the extrusion port And a non-contact type temperature measuring device for measuring the temperature of the cut surface of the rubber extrudate immediately after being cut by the metal wire.

  According to the present invention, a rubber wire extruded from an extruder by fixing a metal wire having a wire diameter of 0.2 mm or more and 0.5 mm or less to a die installed in the extruder, and tensioning the front surface of the extrusion port of the die. Since the object is incised by the metal wire, the contact area between the rubber extrudate and the metal wire becomes very small, and accordingly, the contact time becomes very short. Since the metal wire has a small diameter, the temperature of the rubber extrudate hardly changes even when the extruded rubber extrudate comes into contact. In addition, the thin metal wire has the same temperature as that of the extruded rubber extrudate. And the rubber extrudate can be stably incised at a desired position by restricting the deflection of the metal wire pressed against the rubber extrudate by using a restricting member attached in the vicinity of the extrusion port. Thereby, the influence of the temperature of a metal wire can be minimized and the inside of the rubber extrudate immediately after extrusion can be exposed.

  By measuring the temperature of the exposed cut surface of the rubber extrudate with a non-contact temperature measuring instrument immediately after the cutting, it is possible to suppress the temperature measuring instrument and the external environment from affecting the temperature of the cut surface. Therefore, it becomes possible to measure the internal temperature of the rubber extrudate with higher accuracy than in the past.

It is explanatory drawing which illustrates the temperature measurement unit of the rubber extrudate of this invention. It is a front view which expands and illustrates the die periphery of FIG. It is explanatory drawing which illustrates the tension mechanism of FIG. 2 in a partial cross section view. It is explanatory drawing which illustrates the process of tensioning a metal wire by the tension mechanism of FIG. It is explanatory drawing which illustrates the state which extended | stretched the metal wire to the thickness direction of the extrusion port, and was tense. It is a graph which illustrates the surface distribution and internal temperature distribution of a rubber extrudate.

  Hereinafter, a temperature measurement unit and a temperature measurement method of a rubber extrudate according to the present invention will be described based on the embodiments shown in the drawings.

  The embodiment of the temperature measurement unit 1 of the rubber extrudate of the present invention illustrated in FIGS. 1 and 2 has a metal wire 2 having a wire diameter of 0.2 mm to 0.5 mm and the metal wire 2 attached to an extruder 7. A fixing means 3 for fixing and tensioning the die 8, a regulating member 4 installed in the vicinity of the extrusion port 9 of the die 8, and a non-contact type temperature measuring device 6 are provided. The extruder 7 is a known extruder such as a single screw or a twin screw, and has a screw installed therein. A take-up conveyor 10 is arranged in front of the extrusion port 9, and a support roller 11 is arranged above the take-up conveyor 10.

  The metal wire 2 is disposed on the front surface of the extrusion port 9 of the die 8. In general, the shape of the extrusion port 9 has a width dimension larger than a thickness dimension. In this embodiment, the metal wire 2 extends in the width direction of the extrusion port 9 and is tensioned. As the metal wire 2, a metal wire, a metal cord, or the like is used.

  The fixing means 3 of this embodiment is a fixing screw 3a. The metal wire 2 is detachably fixed to the die 8 by the fixing means 3. The fixing means 3 may be any means as long as the metal wire 2 is fixed to the die 8 and is tensioned.

  The restricting member 4 is a metal plate, for example, and is detachably fixed to the die 8 with screws or the like. The regulating member 4 is fixed to the die 8 so as to cover the metal wire 2 and presses the metal wire 2. For example, the restriction member 4 has a specification that does not easily bend so as to have rigidity higher than that of general carbon steel.

  As the non-contact type temperature measuring device 6, for example, a thermography device or the like is used. The non-contact type temperature measuring device 6 of this embodiment includes a camera 6a and a processing unit 6b. Data photographed by the camera 6a is input to the processing unit 6b, and the data is subjected to image processing indicating the temperature distribution by the processing unit 6b.

  In this embodiment, there is provided a tension mechanism 5 that constantly presses and tensions the metal wire 2 in the direction opposite to the direction of extrusion of the rubber extrudate R. The tension mechanism 5 is constituted by, for example, a guide frame 5a, an adjustment screw 5b, and the like. By pressing the metal wire 2 guided by the guide frame 5a using the adjusting screw 5b, the metal wire 2 is always tensioned. Details will be described later.

  A procedure for measuring the internal temperature of the rubber extrudate R immediately after being extruded from the extruder 7 using the temperature measuring unit 1 will be described.

  First, a predetermined amount of unvulcanized rubber and a compounding agent are charged into the extruder 7. These are mixed and kneaded by the extruder 7. The unvulcanized rubber that has been mixed and kneaded is softened to some extent (plasticized), shaped into the shape of the extrusion port 9 from the extrusion port 9, and extruded as a sheet of unvulcanized rubber extrudate R. Since the metal wire 2 is tensioned on the front surface of the extrusion port 9, the rubber extrudate R is cut up and down by the metal wire 2. The cut rubber extrudate R on the lower side is conveyed downstream by the take-up conveyor 10. The cut-out upper rubber extrudate R is supported by the support roller 11 and conveyed downstream.

  Since the metal wire 2 has a thin diameter of 0.2 mm or more and a diameter of 0.5 mm or less, the contact area with the rubber extrudate R when the rubber extrudate R extruded from the extruder 7 is incised becomes very small. Along with this, the contact time becomes very short. Therefore, even if the rubber extrudate R contacts the metal wire 2, the temperature of the rubber extrudate R hardly changes. Moreover, the metal wire 2 with a small diameter immediately becomes the same temperature as the temperature of the extruded rubber extrudate 2. In addition, since the metal wire 2 is fixed to the die 8, heat in the vicinity of the extrusion port 9 of the die 8 is transmitted to the metal wire 2. Therefore, before the rubber extrudate R is extruded, the metal wire 2 is at a temperature relatively close to the temperature of the rubber extrudate R.

  The movement of the metal wire 2 is restricted by the restriction member 4 at both ends in the width direction of the extrusion port 9. Therefore, the metal wire 2 is restrained from swinging up and down while being pressed by the rubber extrudate R. That is, it is possible to prevent a problem that the rubber extrudate R cannot escape from the metal wire 2 and cannot be cut. Therefore, the rubber extrudate R can be stably incised at a predetermined position, and the inside of the rubber extrudate R immediately after extrusion can be stably exposed without substantially affecting the temperature of the metal wire 2. Can do.

  In addition, when the wire diameter of the metal wire 2 is less than 0.2 mm, the metal wire 2 is easily cut by pressing with the rubber extrudate 2, and the up and down deflection of the metal wire 2 when pressed by the rubber extrudate R is large. Become. On the other hand, when the wire diameter of the metal wire 2 exceeds 0.5 mm, the contact area with the rubber extrudate R increases, and accordingly, the contact time also increases. Thereby, the temperature of the metal wire 2 affects the temperature of the cut surface Rf, and it becomes difficult to accurately measure the internal temperature of the rubber extrudate R.

  The camera 6a images the cut surface Rf of the rubber extrudate R at a position immediately after the rubber extrudate R is cut. The incised surface Rf of the upper or lower rubber extrudate R that has been incised may be photographed. Data captured by the camera 6a is input to the processing unit 6b, where the data is processed and the temperature distribution on the incision surface Rf is measured. That is, the non-contact temperature measuring device 6 measures the temperature of the cut surface Rf of the rubber extrudate R immediately after the cutting without contact. The temperature of the cut surface Rf of the rubber extrudate R immediately after incision is the internal temperature of the rubber extrudate R immediately after extrusion.

  In this way, the temperature of the exposed cut surface Rf of the rubber extrudate R is measured by the non-contact type temperature measuring device 6 immediately after the cutting, so that the temperature of the cut surface Rf depends on the temperature measuring instrument or the external environment. The influence can be suppressed. Therefore, according to the present invention, it is possible to measure the internal temperature of the rubber extrudate R with higher accuracy than before. Since the temperature measurement unit 1 of the present invention can be applied to the existing extruder 1, it has high versatility.

  Since the metal wire 2 continues to be pressed by the rubber extrudate R, the elongation may occur or the tension may be loosened. In such a case, the rubber extrudate R cannot be stably incised at a predetermined position. Therefore, in this embodiment, a tension mechanism 5 is provided as illustrated in FIG. The guide frame 5a constituting the tension mechanism 5 is formed with a guide hole through which the metal wire 2 is guided and a screw hole. The metal wire 2 passes through the guide hole, and the adjustment screw 5b passes through the screw hole. And the pressing piece 5c is inserted. A part of the guide frame 5 a is embedded in the die 8, and the guide hole through which the metal wire 2 passes is at the same level as the front surface of the die 8.

  As illustrated in FIG. 4, by rotating the adjustment screw 5 b and tightening it on the guide frame 5 a, the pressing piece 5 c is pushed in, and this pressing piece 5 c is opposite to the pushing direction of the rubber extrudate R. Always press in the direction. In FIG. 4, the direction from left to right is the extrusion direction of the rubber extrudate R. By constantly pressing the metal wire 2 in the direction opposite to the extrusion direction in this way, the tension state of the metal wire 2 is always maintained, so that the rubber extrudate R can be cut more stably. The tensioning mechanism 5 can be provided not only at one end of the metal wire 2 but also at the other end. The direction in which the metal wire 2 is pressed in order to maintain the tension state of the metal wire 2 can be, for example, the same direction as the extrusion direction of the rubber extrudate R. It can be avoided that an additional burden is generated.

  When the rubber extrudate R is extruded at an extrusion speed of less than 10 cm / sec, the load on the metal wire 2 is not so large. Therefore, when the extrusion speed of the rubber extrudate R is set to be less than 10 cm / sec, the metal wire 2 can be extended in the width direction of the extrusion port 9 to be tensioned as in this embodiment. When the rubber extrudate R is extruded at an extrusion speed of 10 cm / sec or more, the load on the metal wire 2 becomes excessive. Therefore, when the extrusion speed of the rubber extrudate R is set to 10 cm / sec or more, it is preferable that the metal wire 2 is stretched in the thickness direction of the extrusion port 9 to be tensioned as illustrated in FIG. The tension mechanism 5 described above can also be provided in the embodiment illustrated in FIG.

  The internal temperature data of the rubber extrudate R obtained by the present invention can be used effectively when determining the optimum condition setting when the rubber extrudate R is extruded by the extruder 7. Further, since the temperature distribution inside the rubber extrudate R can be grasped, the high temperature portion of the rubber extrudate R can be cooled more intensively and used to prevent burns and to stabilize the member. Burns can be prevented and the yield of the rubber extrudate R can be improved, which contributes to energy saving and is also an ecological measure.

  When an unvulcanized rubber extrudate with the same specifications (width: about 180 mm, thickness: about 15 mm) was extruded under the same conditions using the same extruder, the surface temperature of the rubber extrudate immediately after extrusion was measured with a thermography device (comparison) Example) In addition, the temperature of the cut surface when the rubber extrudate was cut into the upper and lower halves with a metal wire was measured with a thermography device (Example). For measuring the temperature of the cut surface, the same equipment as the temperature measurement unit illustrated in FIGS. 1 and 2 was used, and a metal wire having a wire diameter of 0.4 mm was tensioned in the width direction on the front surface of the extrusion port. The measurement results are schematically shown in FIG. A broken line indicates a comparative example, and a solid line indicates an example.

  From the results of FIG. 6, it can be seen that the measurement temperature of the example is generally higher than that of the comparative example, and the internal temperature of the rubber extrudate immediately after extrusion can be accurately grasped.

DESCRIPTION OF SYMBOLS 1 Temperature measurement unit 2 Metal wire 3 Fixing means 3a Fixing screw 4 Restriction member 5 Tension mechanism 5a Guide frame 5b Adjustment screw 5c Pressing piece 6 Non-contact type temperature measuring device 6a Camera 6b Processing part 7 Extruder 8 Die 9 Extrusion port 10 Pull Taking conveyor 11 Support roller R Rubber extrudate Rf Cut surface

Claims (8)

  A metal wire having a wire diameter of 0.2 mm or more and 0.5 mm or less is fixed to a die installed in an extruder, and tension is applied to the front of the extrusion port of the die, and an unvulcanized rubber extrudate is extruded from the extrusion port. The rubber extrudate immediately after the incision is cut by cutting the extruded rubber extrudate with the metal wire while restricting the deflection of the metal wire pressed by the rubber extrudate with a regulating member attached in the vicinity of the extrusion port. A method for measuring a temperature of a rubber extrudate, wherein the temperature of the cut surface of the rubber is measured with a non-contact type temperature measuring device.   The method for measuring a temperature of a rubber extrudate according to claim 1, wherein the metal wire is always pressed and tensioned in a direction opposite to the extruding direction of the rubber extrudate by a tension mechanism.   The method for measuring a temperature of a rubber extrudate according to claim 1 or 2, wherein the metal wire is stretched in the width direction of the extrusion port and is tensioned, and the rubber extrudate is extruded at an extrusion speed of less than 10 cm / sec.   The method for measuring a temperature of a rubber extrudate according to claim 1 or 2, wherein the metal wire is stretched in the thickness direction of the extrusion port and tensioned, and the rubber extrudate is extruded at an extrusion speed of 10 cm / sec or more.   A metal wire having a wire diameter of 0.2 mm or more and 0.5 mm or less disposed on the front surface of the die extrusion port installed in the extruder, a fixing means for fixing the metal wire to the die and tensioning, and the extrusion port A regulating member that regulates the deflection of the metal wire due to the unvulcanized rubber extrudate extruded from the extrusion port, and the rubber immediately after being extruded from the extrusion port and incised by the metal wire A temperature measurement unit for a rubber extrudate, comprising: a non-contact temperature measuring device for measuring the temperature of the cut surface of the extrudate.   The temperature measurement unit of a rubber extrudate according to claim 5, further comprising a tension mechanism that constantly presses and tensions the metal wire in a direction opposite to the extruding direction of the rubber extrudate.   The temperature measurement unit of a rubber extrudate according to claim 5 or 6, wherein the metal wire is stretched in the width direction of the extrusion port and is tensioned, and the extrusion speed of the rubber extrudate is set to 10 cm / sec or less.   The temperature measurement unit of the rubber extrudate according to claim 5 or 6, wherein the metal wire extends in the thickness direction of the extrusion port and is tensioned, and the extrusion speed of the rubber extrudate is set to 10 cm / sec or more.