JPS595602Y2 - Polymerization structure of tire cord connection part - Google Patents

Description

[Detailed description of the invention] This invention is applicable when a long tire reinforcing material having an integral bead wire is wound and cut into a certain length on a drum-shaped machine and connected in a ring shape. The present invention relates to a polymer structure of a connection part of a tire reinforcement.

Conventionally, in manufacturing pneumatic tires for automobiles, etc., rubberized tire cord is cut into bias shapes, wrapped around a drum-shaped machine, and bead wires connected in a ring shape are fitted on both sides of the cord. The process used to make tire reinforcements consisting of tire cords with integral bead wires, but in recent years, from the viewpoint of manufacturing efficiency, efficiency, or automation of the manufacturing process, the bead wires have been arranged in parallel at predetermined intervals. Long tire reinforcements have come to be used in which tire cord fabric is continuously wound spirally at a fixed angle between two bead wires and then crimped to form an integral piece.

Since this tire reinforcing material is a long continuous body, it is wrapped around a certain shape machine one or more times in succession according to the size of the tire and then cut, and the front and rear ends are cut. They are polymerized and connected to form an annular tire reinforcement, and finally, tread rubber or the like is attached to the upper surface of this to form a green tire.

This invention relates to an overlapping structure of a connecting portion when forming a long tire reinforcement that integrates the tire cord and bead wire into an annular shape.

That is, when a long tire reinforcement is wound around a drum-shaped shaping machine and cut to form an annular tire reinforcement, the front end and the rear end of the tire reinforcement are overlapped and connected. , the overlapping portion at the connection portion becomes a cord layer that is thicker than the non-overlapping portion.

However, partially creating a thick layer of tire cord on the inner circumferential part of the tire causes problems such as uneven weight and uneven thickness, which is not good for the shape or performance of the tire. That's not a good thing.

This invention was proposed based on such recognition, and the details thereof will be explained below according to examples.

FIG. 1 of the accompanying drawings shows a plan view of a long tire reinforcement 10, and FIG. 2 shows an enlarged sectional view thereof, and the tire reinforcements 10 are arranged in parallel at predetermined intervals. 2
A tire cord fabric 13 made of a large number of parallel filaments is continuously wound spirally at a certain angle (corresponding to the crown angle) around the main bead wire 11, 12.
It is constructed in one piece.

Note that the bead wires 11 and 12 are usually provided with rubber called grommet processing, and the tire cord fabric 13 is formed with an adhesive layer 13' such as raw rubber.

Next, as shown in FIG. 3, the long belt-shaped tire reinforcement 10 having the above-mentioned structure is placed on a drum-shaped tire forming machine 20 having a desired diameter one or more times in succession. The layers are wrapped and crimped to form an annular tire reinforcement 15, which is then cut.

In this case, the front end 15a of the annular tire reinforcement 15, which is the beginning of winding on the winding machine 20, and the rear end 15b, which is the cutting point, which is the end of winding, are configured to overlap with each other.

The annular tire reinforcement front end 15a and rear end 15b
In the cut arrow section 16., a portion of the bead wire is left in one or both of them. 17 is formed.

The cut arrow portions 16,17 are formed parallel to the edge lines 15C at both ends, as shown in FIGS. 5a and 6a.

Note that it is preferable that the cutting lines at both ends be diagonal lines parallel to each other in order to connect both parts.

5a and 6a show the annular tire reinforcement 15 in order to clearly explain the relationship between the front end 15a and the rear end 15b.
Although the explanation has been made for a case in which there is a single layer, ordinary ones have two or more layers, and in these cases, there is one or more intermediate layers between the front end 15a and the rear end 15b. will intervene.

The front end 15a and rear end 15b configured as described above are
If an intermediate layer is present, the layers are polymerized so that they overlap slightly, including that layer, and are bonded by being taped with rubber tape or the like at a portion of the bead wire.

This connection of a portion of the bead wire may be performed by caulking as in the conventional method.

Thereafter, a play force, tread rubber, etc. are pasted on the circumferential upper surface of the annular tire reinforcement 15 to form a green tire, which is then vulcanized or shaped to manufacture a tire. .

FIGS. 7a and 7b show the conventional overlapping structure of the tire reinforcement 15, in which the front end 15a and the rear end 15
In the joint part b, there is a tendency that the overlap width of the tire cord portion becomes wider in proportion to the required overlap width of a portion of the bead wire.

In the case of a typical bicycle tire, the width of the conventional overlapping portion 19' is about 8 to 10 mm.

However, in the case of the structure according to this invention, the width of the overlapping portion 19 of the tire cords can be set to 3 to 5 mm, and problems such as uneven weight and uneven thickness occur due to overlapping of the tire cords at the connection point. will be significantly improved and have significant advantages on certain tire shapes or their performance.

The shape of the notches 16 and 17 can be determined by punching them at predetermined positions before forming the long tire reinforcement 10 into an annular shape using a forming machine, which is convenient in terms of the process. It can be done easily and simply.

[Brief explanation of drawings]

Figure 1 is a plan view of the reinforcement for a long tire, Figure 2 is an enlarged sectional view thereof, Figure 3 is a perspective view of the main parts of the reinforcement for a long tire when it is shaped into an annular shape, and Figure 4 is a perspective view of the connecting part, 5th
Figure a is a plan view of a connecting part showing an embodiment of this invention, Figure 5b
The figure is a plan view of the overlapping state, FIG. 6a is a plan view of a connecting part showing another embodiment, FIG. 6b is a plan view of the overlapping state, and FIG. 7 is a conventional structure. FIG. 7a is a plan view of the connecting portion, and FIG. 7b is a plan view of the overlapping state. 10... Reinforcement for long tires, 11, 12
...Bead wire, 13 ... Tire cord, 15 ... Annular tire reinforcement, 15
a, 15 b... end, 15 C...
...Edge line, 16, 17...Notch, 19...
...Polymerization part.

Claims (1)

[Claims for Utility Model Registration] 1. Annular tires made by winding and cutting a long tire reinforcement consisting of a tire cord with an integral bead wire into a fixed length on a shaping machine. At the overlapping joint between the front end and the rear end of the reinforcement, the tire cord section at at least one end of both ends of the tire reinforcement is cut out and connected, leaving only a portion of the bead wire. A polymerized structure of a tire cord connecting portion characterized by reduced overlap. 2. Claims for registration of a utility model characterized in that both ends of the tire reinforcement are cut off by oblique sides parallel to each other, and the cutout of the tire cord portion is formed parallel to the oblique sides. 1. Polymerization structure of the tire cord connecting portion according to item 1. 3. The overlapping structure of a tire cord connecting portion according to claim 1 or 2, wherein the overlapping portions of the beat wires in the connecting portion are connected by tape.