JP6566014B2 - Quality inspection method and quality inspection system for unvulcanized rubber material - Google Patents

Description

  The present invention relates to a quality inspection method and a quality inspection system for an unvulcanized rubber material, and more particularly, an unvulcanized that can easily and quickly grasp the suitability of a compounding ratio of a compounding agent in an unvulcanized rubber material. The present invention relates to a quality inspection method and a quality inspection system for rubber materials.

  When manufacturing rubber products such as tires, there is a step of manufacturing an unvulcanized rubber material by kneading unvulcanized rubber and a compounding agent using a mixer (mixer) or a rubber extruder. In this manufacturing process, the compounding agent is added at a blending ratio set for the unvulcanized rubber. If the proportion of the compounding agent actually added is out of the standard range, the quality of the produced unvulcanized rubber material will be affected. As a result, it affects the quality of rubber products manufactured using this unvulcanized rubber material.

  Conventionally, for example, oxygen flask combustion method and sodium peroxide melting method are known as methods for inspecting the compounding amount of sulfur in unvulcanized rubber materials, but these inspection methods involve complicated procedures and preparations. The time required for the inspection also becomes longer.

  As a method for determining the quality of the unvulcanized rubber material, ultrasonic waves (0.5 MHz to 20 MHz) are transmitted to the extruded unvulcanized rubber material, and the ultrasonic wave intensity transmitted through the unvulcanized rubber material is measured. A method for detecting the amount of attenuation has been proposed (see Patent Document 1). In this proposed method, it is possible to grasp the presence or absence of contaminants and the relative change in the content of unvulcanized rubber material based on the attenuation of ultrasonic intensity. It is not judged whether or not the blending ratio of the compounding agent is appropriate.

  Although the object is not an unvulcanized rubber material, for concrete, a method is known in which the concentration of chloride contained in the concrete, the content, and the like are measured based on the dielectric constant (see, for example, Patent Document 2).

Special table 2014-521948 gazette JP 2006-214941 A

  An object of the present invention is to provide a quality inspection method and a quality inspection system for an unvulcanized rubber material capable of easily and quickly grasping the suitability of the compounding ratio of the compounding agent in the unvulcanized rubber material. .

  In order to achieve the above object, a quality inspection method for an unvulcanized rubber material according to the present invention is based on a dielectric constant of an unvulcanized rubber material in which a predetermined type of compounding agent is mixed with unvulcanized rubber. The blending ratio of the compounding agent in the material is calculated by an arithmetic device, and it is determined by the arithmetic device whether the calculated blending proportion is within or outside a preset blending reference range.

  A quality inspection system for an unvulcanized rubber material according to the present invention includes a dielectric constant measuring device for detecting a dielectric constant of an unvulcanized rubber material in which a predetermined kind of compounding agent is mixed with unvulcanized rubber, and the dielectric constant measuring device. The arithmetic unit to which the dielectric constant detected by is input, and the arithmetic unit calculates the compounding ratio of the compounding agent in the unvulcanized rubber material based on the dielectric constant, and the calculated It is characterized in that it is determined whether the blending ratio is within or outside the blending standard range input to the arithmetic unit.

  According to the present invention, if the dielectric constant of the unvulcanized rubber material is detected, the blending ratio of the compounding agent of the unvulcanized rubber material is calculated by performing an arithmetic process using an arithmetic unit based on the dielectric constant. Thus, the suitability of the blending ratio can be quickly determined. In addition, since it is not necessary to acquire data using various solutions, the inspection can be performed easily.

It is explanatory drawing which illustrates the quality inspection system of the unvulcanized rubber material of this invention. It is a graph which illustrates typically the relationship between each of the compounding ratio of carbon black and the compounding ratio of a masterbatch, and the dielectric constant of an unvulcanized rubber material. It is explanatory drawing which illustrates the content (A time-dependent change of the mixture ratio of a compounding agent) displayed on a monitor. It is explanatory drawing which illustrates another content (dispersion degree of a compounding agent) displayed on a monitor.

  Hereinafter, the quality inspection method and quality inspection system of the unvulcanized rubber material of the present invention will be described based on the embodiments shown in the drawings.

  An unvulcanized rubber material quality inspection system 1 of the present invention illustrated in FIG. 1 (hereinafter referred to as inspection system 1) receives a dielectric constant measuring device 2 and a dielectric constant detected by the dielectric constant measuring device 2. An arithmetic device 3 and a monitor 3a connected to the arithmetic device 3 by radio or wire are provided. The present invention provides a primary rubber material R1 in which a predetermined type of non-vulcanized compounding agent Ac is mixed with unvulcanized rubber M, and a final rubber material in which a predetermined type of vulcanized compounding agent As is mixed with primary rubber material R1. Any unvulcanized rubber material R of R2 can be the inspection object, but in this embodiment, the final rubber material R2 immediately after being extruded by the extruder 4 is the inspection object.

  Examples of the non-vulcanizing compounding agent Ac include carbon black and silica. Examples of the vulcanizing compounding agent As include at least one of a vulcanization activator, a vulcanization acceleration aid, and sulfur. A master batch in which a vulcanization activator, a vulcanization accelerator and sulfur are mixed in a specified ratio may be used as the vulcanizing compound As.

  The extruder 4 includes a cylinder 4a in which a rotationally driven screw is installed, a material charging port 4b formed on the upper surface of the rear end portion of the cylinder 4a, a hopper 4d installed in the material charging port 4b, And an extrusion port 4c formed at the tip of 4a. A conveying means such as a conveyor extends in front of the extrusion port 4c. In addition, a compounding agent supply unit 5 for supplying a predetermined type of vulcanizing compounding agent As to the material charging port 4b through the hopper 4d is installed.

  The sheet-like primary rubber material R1 is continuously fed into the cylinder 4a of the extruder 4 from the material charging port 4b through the hopper 4d. Further, a predetermined kind of vulcanizing compound As is continuously fed from the material charging port 4b through the hopper 4d by the compounding agent supply unit 5. The vulcanized compounding agent As is set to be charged at a predetermined ratio with respect to 100 parts by weight of the unvulcanized rubber M.

  The charged primary rubber material R1 and vulcanizing compounding agent As are moved forward while being mixed and kneaded in the cylinder 4a by a rotating screw. And the last rubber material R2 shape | molded in the sheet form from the extrusion port 4c is extruded continuously, and is manufactured.

  The dielectric constant measuring device 2 can use various devices with various known specifications. A device capable of detecting the dielectric constant in a non-contact manner by irradiating the inspection object (unvulcanized rubber material R) with ultrasonic waves is preferable. For example, while permitting the final rubber material R2 being extruded to pass through, the dielectric constant in the range through which the final rubber material R2 has passed is sequentially detected by the dielectric constant measuring device 2.

  Not only one dielectric constant measuring instrument 2 but also a plurality of dielectric constant measuring instruments 2 can be arranged in parallel in the width direction of the final rubber material R2. Alternatively, the dielectric constant measuring device 2 can be configured to be movable in the width direction of the final rubber material R2. By adopting these configurations, it is possible to inspect substantially the entire width of the final rubber material R2.

  As illustrated in FIG. 2, correlation data between the blending ratio of a predetermined type of vulcanizing compounding agent As in the final rubber material R2 and the dielectric constant of the final rubber material R2 is input to the arithmetic device 3. Specifically, as the blending ratio of the master batch used as the vulcanizing compounding agent As increases, the dielectric constant of the final rubber material R2 tends to decrease. The arithmetic device 3 calculates the blending ratio D1 of the vulcanizing compound As in the final rubber material R2 based on the correlation data and the sequentially input dielectric constant.

  In this embodiment, correlation data between the blending ratio of the predetermined type of non-vulcanizing compounding agent Ac in the primary rubber material R1 and the dielectric constant of the primary rubber material R1 is also input to the arithmetic unit 3. Specifically, the dielectric constant of the primary rubber material R1 tends to increase as the blending ratio of carbon black used as the non-vulcanizing compounding agent Ac increases. Depending on the type of compounding agent A (Ac, As), the correlation between the compounding ratio and the dielectric constant of unvulcanized rubber material R mixed with compounding agent A (whether the dielectric constant increases proportionally or decreases) , And the degree of change in the dielectric constant), the correlation data is acquired in advance for each compounding agent A to be used and input to the arithmetic unit 3.

  Further, a blending reference range C1 indicating an appropriate blending ratio for each type of the vulcanizing compounding agent As is input to the arithmetic device 3. Then, as illustrated in FIG. 3, the arithmetic device 3 sequentially compares the calculated blending ratio D1 and the blending reference range C1 and sequentially determines whether the blending ratio D1 is within or outside the blending reference range C1. To do.

  The determination result by the arithmetic device 3 is sequentially displayed on the monitor 3a. The determination result to be displayed may be a warning simply indicating that the calculated blending ratio D1 is outside the blending reference range C1, or the time-dependent change of the blending ratio D1 illustrated in FIG. 3 may be sequentially displayed.

  As described above, according to the present invention, the blending ratio of the vulcanizing compounding agent As of the final rubber material R2 is calculated by detecting the dielectric constant of the final rubber material R2 and performing arithmetic processing based on the dielectric constant. Thus, the suitability of this blending ratio can be quickly judged by nondestructive inspection. Moreover, since it is not necessary to acquire data using various solutions as in the conventional inspection method, the inspection can be easily performed.

  By the way, even if the vulcanized compounding agent As is added to the primary rubber material R1 at a compounding ratio that satisfies the compounding standard range C1, the vulcanized compounding agent As is based on the unvulcanized rubber M (primary rubber material R1). If not sufficiently dispersed and mixed, the quality of the manufactured final rubber material R2 is affected. Therefore, it is more preferable to adopt a configuration in which the suitability of the degree of dispersion of the vulcanizing compounding agent As is also judged.

  Therefore, the extruded final rubber material R2 is divided into a number of sections in plan view, and the dielectric constant is detected for each of the sections. And based on the magnitude | size of the variation of the detected dielectric constant of each division, the arithmetic unit 3 calculates the dispersion degree D2 of the vulcanizing compound additive As in the final rubber material R2.

  A dispersion reference range C2 indicating an appropriate dispersion degree D2 is input to the arithmetic device 3 for each type of vulcanizing compounding agent As. Then, the arithmetic device 3 sequentially compares the calculated dispersion degree D2 and the dispersion reference range C2, and determines whether the dispersion degree D2 is within or outside the range of the dispersion reference range C2.

  For example, a reference dielectric constant Cd is set, and an absolute value of a deviation between the reference dielectric constant Cd and the dielectric constant of each section is averaged over a predetermined area range (per unit area) to a dispersion degree D2. To do. The greater the dispersion degree D2, the better the vulcanizing compound As is not dispersed. Therefore, the preset average allowable range is set to the dispersion reference range C2, and the dispersion degree D2 is larger than the dispersion reference range C2. In such a case, it is determined that the degree of dispersion is poor.

  Even when the dielectric constant is locally too large or too small, it can be said that the vulcanized compounding agent As is not well dispersed. Therefore, it is also possible to determine that the degree of dispersion is poor when a local allowable range set in advance is set as the dispersion reference range C2 and there is a section having a dispersion degree D2 larger than the dispersion reference range C2. At least one of the above-described average allowable range and local allowable range can be adopted as the dispersion reference range C2, but it is preferable to adopt both.

  The determination result by the arithmetic device 3 is sequentially displayed on the monitor 3a. The determination result to be displayed may be a warning that simply informs that the calculated dispersion degree D2 is outside the dispersion reference range C2. However, as illustrated in FIG. 4, the distribution of the dielectric constant (or blending ratio D1) is illustrated. It can also be configured to display.

  When the display is configured as shown in FIG. 4, each section is divided into a plurality of classes (for example, indexes such as ~ 85, 85 to 95,...) By the arithmetic unit 3 according to the dielectric constant. To do. Then, each section is displayed on the monitor 3a so that the classified classes can be identified. In FIG. 4, the classified classes can be identified by using a pattern such as a blank or a line. However, it is preferable that the classes can be identified by the difference in color or the shade of color. By making such a display, it is possible to easily grasp the suitability of the vulcanizing compound As as dispersed just by looking at the monitor 3a.

  The above-described contents can be similarly applied to the primary rubber material R1. That is, by detecting the dielectric constant of the primary rubber material R1 and performing arithmetic processing based on this dielectric constant, it is possible to quickly determine whether or not the blending ratio and blending ratio of the non-vulcanized compounding agent Ac of the primary rubber material R1 are appropriate. it can. Moreover, it becomes possible to grasp the suitability of the dispersion of the non-vulcanizing compounding agent Ac in the primary rubber material R1 as in the case of the final rubber material R2.

DESCRIPTION OF SYMBOLS 1 Inspection system 2 Permittivity measuring device 3 Arithmetic unit 3a Monitor 4 Extruder 4a Cylinder 4b Material inlet 4c Extrusion port 4d Hopper 5 Compounding agent supply part R Unvulcanized rubber material R1 Primary rubber material R2 Final rubber material M Unvulcanized Rubber A Compounding agent Ac Non-vulcanizing compounding agent As Vulcanizing compounding agent C1 Compounding standard range C2 Dispersion standard range

Claims (8)

  Based on the dielectric constant of the unvulcanized rubber material in which a predetermined type of compounding agent is mixed with unvulcanized rubber, the compounding ratio of the compounding agent in the unvulcanized rubber material is calculated by an arithmetic unit, and the calculated compounding ratio A method for inspecting the quality of an unvulcanized rubber material, characterized in that it is determined by the arithmetic unit whether or not is within a pre-set compounding reference range.   The unvulcanized rubber material is divided into a number of sections in a plan view, the dielectric constant is detected for each section, and the arithmetic unit determines the variation in the dielectric constant of each detected section. The degree of dispersion of the compounding agent in the unvulcanized rubber material is calculated, and it is determined whether the calculated degree of dispersion is within or outside a preset dispersion reference range. Quality inspection method for vulcanized rubber materials.   Each of the sections is divided into a plurality of classes by the arithmetic unit according to the dielectric constant of each of the sections, and each of the sections is displayed on a monitor so that the classified classes can be identified. Item 3. A quality inspection method for an unvulcanized rubber material according to Item 2.   The method for quality inspection of an unvulcanized rubber material according to any one of claims 1 to 3, wherein the compounding agent is at least one of carbon black, silica, a vulcanization activator, a vulcanization acceleration aid, or sulfur.   A dielectric constant measuring device for detecting a dielectric constant of an unvulcanized rubber material in which a predetermined type of compounding agent is mixed with unvulcanized rubber; and an arithmetic unit for inputting the dielectric constant detected by the dielectric constant measuring device; The blending ratio of the compounding agent in the unvulcanized rubber material is calculated by the computing device based on the dielectric constant, and the computed blending ratio is input to the computing device. A quality inspection system for unvulcanized rubber material, characterized in that it is determined whether it is within or outside the range.   The dielectric constant is detected for each of a plurality of sections divided in plan view of the unvulcanized rubber material, and based on the magnitude of variation in the dielectric constant of each detected section, The degree of dispersion of the compounding agent in the unvulcanized rubber material is calculated, and it is determined whether the calculated degree of dispersion is within or outside a preset dispersion reference range. Quality inspection system for unvulcanized rubber materials.   A monitor connected to the arithmetic device wirelessly or by wire; each of the sections is divided into a plurality of classes by the arithmetic device in accordance with the dielectric constant of each of the sections; 7. The quality inspection system for an unvulcanized rubber material according to claim 6, wherein the classified class is identifiable and displayed on the monitor.   The quality inspection system for an unvulcanized rubber material according to any one of claims 5 to 7, wherein the compounding agent is at least one of carbon black, silica, a vulcanization activator, a vulcanization acceleration aid, or sulfur.

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