JPH07223413A - Transponder for tire - Google Patents

Abstract

PURPOSE:To provide strength and elasticity which are necessary for protecting electric parts of a main body so as to improve durability of the main body and tire by coating the outer surface of a transponder with a resin provided with a covulcarnization property with rubber. CONSTITUTION:A transponder 1 is embedded in a projection 4 arranged inside a tire bead part 3 installed in a rim 2 with its longitudinal direction set in the circumferential direction of a tire. A synthetic resin layer for covering the outline a glass container of the transponder 1 is formed of a resin having a covulcarnization property with rubber. Therefore, mechanical strength and elasticity required for protecting electric parts in a main body installed inside the transponder 1 can be provided, while durability and reliability of the transponder 1 and durability of the tire in which the transponder 1 is embedded can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transponder coating material which is embedded in a tire to record and transmit various information regarding the individual tire.

[0002]

2. Description of the Related Art A transponder having both a function of a receiver and a transmitter is built in a tire, and information such as an internal pressure as a condition of use of the tire, a load per tire, and a number of revolutions of the tire indicating a mileage of the tire are stored. The technology of storing and taking out individual tires when necessary is the actual Kaihei 2-1.
It is disclosed in Japanese Patent No. 23404.

This transponder is composed of an integrated circuit, a coil, and an outer shell for protecting the transponder. The transponder has various shapes such as a coin shape or a cylindrical shape (for example, a cylindrical shape having a length of 20 to 20). 30mm, diameter 4-5
The thing of mm is common. ) Further, as the position where the transponder is embedded in the tire, as shown in the above-mentioned publication, the tip region of the upper part of the carcass ply winding (usually the part directly beside the inside of the bead wire) or the buttress part (the tire diameter of the side wall part) The outer side surface of the carcass ply (outer end in the direction) is currently considered to be appropriate. Furthermore, when the transponder, which is an electronic component, is embedded in the tire, the vulcanization heat during tire production, various external forces, heat, and humidity received during running,
Since the structure of the transponder is required to withstand the impact when installing or removing the tire from the wheel, the structure of the transponder is such that the integrated circuit and the coil are housed in a glass container for waterproofing and the whole is excellent in impact resistance. It is protected by a double-structured shell covered with synthetic resin. As the synthetic resin having excellent impact resistance, polyphenylene sulfide (PPS) and polybutylene terephthalate (PB) have recently been shown to have suitable mechanical strength and moldability.
T), polyethylene terephthalate (PET), ABS
Resins and the like are candidates.

[0004]

However, since the criteria for selection of these synthetic resins are focused only on impact resistance, mechanical strength, and formability, they can be used under severe conditions during tire running. The joining between these resins forming the outer shell of the transponder and the rubber member of the tire has not been sufficient. That is, as described above, burying the transponder in the tire corresponds to burying foreign matter in the tire. In order to prevent the destruction of the transponder, it is necessary that the adhesion between the resin and the rubber, which is the outer shell of the transponder, is sufficiently taken. For this reason, in the past, it was attempted to treat the surface of the transponder with an adhesive such as Chemloc, but when the Chemloc surface is treated, the treated surface is exposed to a high temperature of hundreds of tens of degrees. The electric circuit of the transponder is easily damaged, and it is difficult to perform a sufficient bonding process. Therefore, the durability of the transponder is reduced and the durability of the tire body is also reduced.

The object of the present invention is to provide the tire rubber without impairing the durability of the body of the transponder while having the mechanical strength and elasticity required for protecting the electric parts of the body loaded inside the transponder. The object is to provide a transponder covered with an outer member that forms a strong bond with the member, and further to improve the durability of the tire in which the transponder is embedded.

[0006]

In order to achieve the object of the present invention, first of all, the transponder of the present invention is a transponder embedded in a tire as described in the above-mentioned claim 1 and has an outer surface The tire transponder is characterized by being coated with a resin having co-vulcanizability with rubber. Further, in the transponder according to the present invention as set forth in claim 2, a resin having a co-vulcanization property with rubber and having a melting point equal to or higher than the vulcanization temperature of the rubber at the position to be embedded in the tire. The outer surface of the tire is covered with a transponder for a tire. Next, as described in claim 3, a transponder coated with a resin having a co-vulcanization property with rubber and having a melting point equal to or higher than the vulcanization temperature of the rubber at a position to be embedded in the tire is predetermined. Provided is a tire characterized by being buried in a position. Syndiotactic 1,2 polybutadiene (SPB) resin, styrene butadiene (SB) resin, and the like are known as resins that have co-vulcanizability with rubber, but transponders are subject to significant deformation. In consideration of being used by being embedded in a rubber member of a relatively soft tire to be received, a resin having elasticity as flexible as possible is selected. For example, in the case of syndiotactic 1,2 polybutadiene (SPB) resin, one having a melting point of 150 to 210 degrees is more preferable because it satisfies the above conditions.

[0007]

In the present invention, the resin having the co-vulcanization property with rubber is used as the outer shell member of the transponder. When the resin having such characteristics is embedded in the rubber, a strong cross-linking structure may be formed between the rubber and the boundary surface when the rubber which is the tire member is vulcanized during the tire vulcanization. Known,
For example, it can be considered that the rubber and the resin are chemically bonded via sulfur as a crosslinking agent mixed in the rubber. Therefore, the transponder is not exposed to high temperatures like the bonding with existing adhesives such as Chemlock, and it does not damage the electrical circuit of the transponder.
In addition, a strong joint that can sufficiently withstand external stimuli such as impact, deformation, and heat received during tire use can be obtained.
Further, in the present invention, a resin having elasticity as much as possible is selected from the resins having such co-vulcanizability, so that it is possible to more flexibly cope with the impact and deformation received when the tire is used. Furthermore, in the present invention, as described in claim 2, when the resin is embedded in a tire as an outer protective layer of a transponder and is vulcanized together with a tire rubber member, the resin is vulcanized so as not to be melted by a vulcanization temperature. Since a resin having a melting point equal to or higher than the vulcanization temperature is selected, it is possible to prevent troubles such as the resin flowing due to vulcanization heat to separate from the transponder, or a non-uniform coating film is formed.

On the other hand, when the resin having the above-mentioned characteristics is used as the outer protective layer of the transponder, the interface peeling between the outer shell of the transponder and the tire rubber member in the buried portion, which has been a problem in the past, is prevented. Therefore, the durability of the tire with a built-in transponder is significantly improved.

[0009]

EXAMPLES The present invention will be specifically described below with reference to examples. FIG. 1 shows a cylindrical transponder (1) according to the present invention in which a longitudinal direction of a tire is provided in a protrusion (4) provided inside a bead portion (3) of a tire mounted on a rim (2). It shows a state of being buried in the circumferential direction. In this embodiment, the tire is a truck tire of size 11R22.5, and the transponder has a diameter of 5 mm.
It has a cylindrical shape with a length of 30 mm and a length of 30 mm. Further, as shown in FIG. 2, the detailed shape structure of the transponder is a package in which an antenna coil (5) in charge of transmission and reception and an integrated circuit for extracting or storing necessary data as an electric quantity are incorporated. (6) and the like are housed in a cylindrical glass container (7) to have water resistance, and the outer shell of the glass container is further covered with a synthetic resin layer (8) having a thickness of 1 mm. It has become a thing. Then, as a material of the synthetic resin layer serving as the outer shell, a material adopting SPB resin having a melting point of 200 degrees was set as Example 1, and a case of using SB resin having a melting point of 180 degrees was set as Example 2. Here, the tire in which the transponder is embedded is vulcanized at a vulcanization temperature lower than the melting points of the above resins.

Next, in order to confirm the effect of the present invention, PE which has been conventionally used as the material of the synthetic resin as the outer shell is used.
Tires of Comparative Example 1 and Comparative Example 2 in which transponders employing T and PPS were embedded were separately manufactured, and an interface peeling test was performed together with the tires of Examples 1 and 2 described above. This boundary surface peeling test is carried out by vulcanizing tires in which transponds using various synthetic resins are embedded under predetermined vulcanization conditions, cutting out transponders from these tires together with peripheral tire rubber members, and using a peeling tester. The amount of rubber adhered to the synthetic resin surface after being peeled off at the boundary layer between the attached tire rubber member and the synthetic resin is evaluated. The results of the tests carried out in this way are shown in Table 1. From this, it can be seen that the SPB resin and SB resin used in the examples have extremely excellent adhesion performance.

[0011]

[Table 1]

An indoor drum durability test was conducted using the tires of Examples 1 and 2 and Comparative Examples 1 and 2. JIS standard 100% for test condition and test method
After applying 50,000 km of internal pressure and load to the tire at a speed of 50 km / h, remove the tire from the drum tester,
The tire is cut at the part where the transponder is embedded, and the peeling condition around the transponder is checked. As a result of the test, no peeling was confirmed in the tires of Examples 1 and 2, but in the case of Comparative Examples 1 and 2, minute peeling was scattered around the transponder.

[0013]

By using the transponder according to the present invention in a tire, it can be expected that the durability and reliability of the transponder and the durability of the tire in which the transponder is embedded are dramatically improved.

[Brief description of drawings]

FIG. 1 is a sectional view of a bead portion of a tire having a transponder according to the present invention embedded therein.

FIG. 2 is an enlarged sectional view of the transponder of the present invention.

[Explanation of symbols]

 1 transponder 2 rim 3 tire bead part 4 protrusion 5 antenna coil 6 package 7 glass container 8 synthetic resin

Claims (3)

[Claims] 1. A transponder embedded in a tire, the outer surface of which is covered with a resin having co-vulcanizability with rubber. 2. The tire transponder according to claim 1, wherein the resin has a melting point equal to or higher than the vulcanization temperature of the rubber in which the transponder is buried. 3. A tire having a built-in transponder whose outer surface is coated with a resin having a vulcanization property with a rubber in which the transponder is buried and having a melting point higher than the vulcanization temperature of the rubber.