JP2012037325A - Method for testing unvulcanized carcass ply - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for testing unvulcanized carcass ply by which drawing drag of a ply cord and positional relation between the cord and rubber or the like are evaluated by the unvulcanized carcass ply.SOLUTION: When the drawing drag of the ply cord 4 is tested by a sample of the unvulcanized carcass ply consisting of a rubber drawing layer including a plurality of ply cords 4 in parallel by drawing, a sample 2 of the unvulcanized carcass ply is expanded at arbitrary expansion rate in the direction perpendicular to the extension direction of the cord 4 and after that, a hard member 6 is adhered to at least one surface of the sample 2.

Description

  The present invention relates to a method for testing an unvulcanized carcass ply.

The carcass constituting the skeleton structure of the product tire is usually formed of one or more carcass plies made of a rubberized layer in which a plurality of ply cords are arranged in parallel and the cords are covered with rubber.
In forming a raw tire for manufacturing such a tire, an unvulcanized carcass ply is expanded and deformed in a shaping process or the like, and therefore, a ply cord embedded in the tire and an unvulcanized rubber There was a possibility that a clearance was generated between the ply cord and the pulling resistance of the ply cord was lowered.

  For this reason, in order to measure the pulling force of the uncured carcass ply ply cord, the uncured carcass ply sample is pulled out in a state of being expanded and deformed in correlation with the above-mentioned expanded deformation. Measuring force (pull-out drag) has been done.

  However, in such a pull-out measurement method, the ply cord is pulled out while maintaining a state in which the uncured carcass ply is expanded and deformed to a required expansion rate in a direction perpendicular to the extending direction of the cord by a tensile tester. Therefore, it is necessary to have two devices, one for expanding the carcass ply and the other for pulling out the cord, and it is necessary to develop a dedicated device for that purpose. The rate was inevitable.

  On the other hand, when the pulling resistance is measured in the unexpanded sample state without expanding the uncured carcass ply sample as compared with the case where the pulling resistance of the ply cord of the expanded sample is measured. Since the measurement results differ greatly, it was not an actual carcass ply measurement method.

  In addition, conventionally, there has been no method for accurately evaluating the gap and positional relationship between the ply cord and the unvulcanized rubber when the unvulcanized carcass ply is expanded and deformed.

  An object of the present invention is to provide an unvulcanized carcass ply test method capable of evaluating the pulling resistance of a ply cord, the positional relationship between the cord and rubber, and the like with the unvulcanized carcass ply.

  In one embodiment of the present invention, when testing the unbonded carcass ply with a sample of unvulcanized carcass ply composed of a rubberized layer in which a plurality of ply cords are aligned in parallel, After the sample is expanded at an arbitrary expansion rate in a direction perpendicular to the extending direction of the cord, a hard member is bonded to at least one surface of the sample.

  Here, the “arbitrary expansion rate” refers to a ratio in which the interval is expanded in the range of 100 to 400% compared to the reference when the interval between codes processed by the calendar is used as a reference.

  More preferably, in such a test method, the hard member is bonded to both sides of the sample of the unvulcanized carcass ply.

  One embodiment of the present invention is a sample of an unvulcanized carcass ply composed of a rubberized layer in which a plurality of ply cords are aligned in parallel, and the gap between the ply cord and the unvulcanized rubber is tested. After the uncured carcass ply sample is expanded at an arbitrary expansion rate in the direction perpendicular to the direction in which the cord extends, the gap formed between the rubber and the cord is filled with a hardened material, and the unvulcanized afterwards The rubber and the cured material are taken out by peeling off the rubber.

  In one embodiment of the present invention, an unvulcanized carcass ply sample is expanded to a required expansion rate in a direction orthogonal to the direction in which the ply cord extends, and then a hard material is bonded to at least one surface of the sample. Even after the expanded unvulcanized carcass ply sample is removed from the tensile tester, the required expanded state can be maintained, so that the unvulcanized carcass ply sample is expanded, With one pulling device, the pulling resistance can be measured easily and at low cost.

  In another embodiment of the present invention, after a sample of an unvulcanized carcass ply is expanded at an arbitrary expansion rate in a direction orthogonal to the extending direction of the cord, the gap formed between the rubber and the cord is cured. It is formed between the unvulcanized rubber and the cord in the expanded state of the unvulcanized carcass ply by embedding with a cured material such as gypsum and plaster and then stripping off the unvulcanized rubber and taking out the cord and the cured material. The gap can be shaped, and its cross-sectional shape can be directly observed and evaluated.

  In addition, in the present invention, the pulling resistance at the time of expansion, the void ratio, the amount of rubber attached to the cord, etc. can be used as development evaluation items, and the carcass ply in the product tire is in the gap in the sign management after mass production. The ply wave derived from playing the cord, etc., the cord is pulled out to the center side in the shaping process, etc., or the carcass ply folded height is not located at the specified height, or a predetermined amount just below the bead core It is possible to prevent product defects such as the rubber thickness not being reached.

It is a perspective view which shows the state which expanded the sample of the unvulcanized carcass ply used with the test method of the unvulcanized carcass ply which concerns on one Embodiment of this invention with the expansion apparatus. It is a perspective view shown with the hard member which made the sample adhere | attach the unvulcanized carcass ply used with the test method of the unvulcanized carcass ply which concerns on one Embodiment of this invention. It is an enlarged side view which shows the state which embedded the resin member, after pulling the unvulcanized carcass ply used with the test method of the unvulcanized carcass ply which concerns on other embodiment of this invention. It is a perspective view which shows the state which peeled off the rubber | gum of the unvulcanized carcass ply shown in FIG.

Hereinafter, a method for testing a sample of an unvulcanized carcass ply of the present invention will be described in detail with reference to the drawings.
In the figure, reference numeral 1 denotes an entire expansion device for expanding a sample of an unvulcanized carcass ply. The expansion device 1 is provided with clamping means 3 for clamping an unvulcanized carcass ply sample 2 in the vertical direction in the figure.
Here, the unvulcanized carcass ply sample 2 is composed of a rubberized layer of unvulcanized rubber 5 in which a plurality of ply cords 4 are aligned in parallel.

  In this expansion device 1, the unvulcanized carcass ply sample 2 is extended on both sides of the unvulcanized carcass ply sample 2 in such a direction that the unvulcanized carcass ply sample 2 can be expanded in a direction perpendicular to the extending direction of the cord 4 by the upper and lower clamping means 3. Hold the end.

  And the clamping means 3 is moved to the up-down direction, and the unvulcanized carcass ply sample 2 is expanded in an arbitrary expansion rate, preferably in the range of 100 to 200% equivalent to the expansion rate of the ply in the raw tire. Next, the hard member 6 is bonded and fixed to at least one surface of the unvulcanized carcass ply sample 2 in the figure, while maintaining that state, for example, using an adhesive or glue.

  In the present invention, after the uncured carcass ply sample 2 is removed from the expansion device 1, as shown in the perspective view of the unvulcanized carcass ply in FIG. However, the unvulcanized carcass ply sample 2 can maintain the expanded state. With the sample, it is possible to measure the pulling drag force of the ply cord in a state in which it is expanded and deformed in correlation with expansion deformation such as a shaping process.

  Here, the material and shape of the hard member 6 are not particularly limited, but the expanded state can be maintained after the unvulcanized carcass ply sample 2 is expanded and removed from the expansion device 1, and the unvulcanized carcass ply sample can be maintained. It is sufficient if it is a plate having rigidity that can withstand the rubber shrinkage force of 2 or more, and specifically, a wooden plate, an iron plate, a plastic plate or the like having a predetermined shape can be mentioned.

  In such an unvulcanized carcass ply test method, more preferably, the expanded state can be more reliably maintained over a long period of time by bonding the hard member 6 to both surfaces of the unvulcanized carcass ply sample 2.

FIG. 3 is an enlarged side view showing a state in which a cured material is embedded after pulling an unvulcanized carcass ply used in a test method for an unvulcanized carcass ply according to another embodiment of the present invention.
After the unvulcanized carcass ply sample 2 is expanded and preferably fixed by the hard member 6, the cured material 7 is placed in the gap formed between the unvulcanized rubber 5 and the cord 4 of the unvulcanized carcass ply sample 2. For example, it is preferable to pour liquid resin and dry for a certain period of time to fix the gap.

  By fixing the gap in this manner, the unvulcanized rubber 5 of the unvulcanized carcass ply sample 2 is peeled off, and the cured material 7 and the cord 4 as shown in the perspective view of FIG. A gap formed between the unvulcanized rubber 5 and the cord 4 can be formed by expansion deformation of the vulcanized carcass ply sample 2, and its cross-sectional shape and the like can be observed and evaluated.

  Although the hardening material 7 is not specifically limited, An epoxy resin, an acrylic resin, a urethane resin, a polyester resin, a phenol resin, gypsum etc. can be mention | raise | lifted.

DESCRIPTION OF SYMBOLS 1 Expansion apparatus 2 Unvulcanized carcass ply sample 3 Clamping means 4 Ply cord 5 Unvulcanized rubber 6 Hard member 7 Curing material

Claims (3)

In testing the pulling resistance of the ply cord with a sample of an unvulcanized carcass ply consisting of a rubberized layer in which a plurality of ply cords are aligned in parallel,
A method for testing an unvulcanized carcass ply, in which a sample of the unvulcanized carcass ply is expanded at an arbitrary expansion rate in a direction orthogonal to the extending direction of the cord, and then a hard member is bonded to at least one surface of the sample.   The method for testing an unvulcanized carcass ply according to claim 1, wherein the hard member is adhered to both surfaces of a sample of the unvulcanized carcass ply. When testing the gap between the ply cord and the unvulcanized rubber with a sample of an unvulcanized carcass ply consisting of a rubberized layer in which a plurality of ply cords are aligned in parallel,
The unvulcanized carcass ply sample is expanded at an arbitrary expansion rate in a direction perpendicular to the extending direction of the cord, and then a gap formed between the rubber and the cord is filled with a hardening material, and the unvulcanized material is added afterwards. A method for testing an unvulcanized carcass ply by peeling off the vulcanized rubber and taking out the cord and the cured material.

Images