JPS6012317A - Semi-radial tyre for motorcycle - Google Patents

Abstract

PURPOSE:To improve the abrasion resistance and high speed withstandability by turning the carcass of radial tyre for motorcycle at the bead section then laminating at the tread section and surrounding the belt layer. CONSTITUTION:A radial carcass is comprised of a sheet of ply where the circumference of a pair of bead wires is turned at the opposite ends of ply and wound to constitute each turn-up section P-2 while the opposite ends P-E are overlapped at the tread crown section to surround the belt layer B-1. Such belt construction where its motion between the overlapped layer and carcass layer is limited by the carcass terminal constructed immediately below the tread crown center will exhibit the abrasion resistance and high speed withstandability.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention (engineering, motorcycle tire case 14U)
This invention relates to a method for improving the steering stability of tires, which varies slightly depending on the vehicle's characteristics.

For passenger car tires, handling stability, wear resistance,
Tires with radial structure, which are superior in terms of high-speed durability, have already become mainstream, but these radial tires use carcass fiber cords or steel cords, and the cord angle is aligned with the circumferential center line of the tire. In contrast, one ply or several plies arranged in the 90° direction, that is, the radial direction, is used as the belt layer, and the belt layer is made of steel cord, rayon, etc. l! A belt made by using one or two or more fibers with a low ratio: ff-do at an inclination angle of 15 to 60 degrees with respect to the center line in the circumferential direction of the tire, and when two or more fibers are used, they are overlapped and crossed each other. It is well known that the tires have a structure with reinforced layers, but compared to tires with a radial structure and the bias structure tires that were the mainstream, The sidewalls (hereinafter referred to as sidewalls) are extremely flexible, providing a comfortable ride.A highly rigid belt layer is placed directly under the tread, so pantographs can be attached to the tread contact surface, similar to those found in bias tires. The high rigidity of the belt layer spreads to the separating surface, resulting in high cornering characteristics, that is, excellent steering stability, and at the same time, the movement of the rubber on the contact surface is not small, which improves wear resistance. This means that it exhibits excellent characteristics on the surface.

By the way, if you think about motorcycle tires, the fact that the sidewall μ is flexible means that when the motorcycle turns or takes a curve, the body of the motorcycle leans toward the side of the turn. A camber angle is given to the tire, but in opposition to the centrifugal force acting on the horizontal plane, a lateral force, ie, a camber thrust, is generated as a restoring force against the lateral deformation of the tire due to the presence of the camber angle. It is well understood from the military structure that the size of this camper thrust plays a very important role in dealing with disturbances when the two-wheeled vehicle turns and moves straight. As for the structure of motorcycle tires that require curves or turning movements at an angle, tires with a flexible radial sidewall are unstable in terms of lateral deformation, and this phenomenon is caused by disturbances when driving straight. He also responds sensitively to his father. In addition, motorcycles, which are often driven at high speeds, have poor lateral stability as mentioned above, that is, poor handling stability, which can be fatal, unlike in the case of four-wheeled vehicles, because poor handling stability is associated with the risk of rollover. It becomes a defect.

As a result of extensive research into the sidewall rigidity and contact surface rigidity required for motorcycle tires, mainly from the viewpoint of the carcass and belt structure, the present inventor discovered the carcass from the sidewall to the crown and its winding structure. By adding a unique twist to the belt structure, it is not only possible to eliminate the drawbacks of the radial cycle tires mentioned above, but it is also superior to conventional bias tires in terms of wear resistance and high-speed steel durability. It has been found that this method has an effect that was previously unavailable.

This invention provides a semi-radial tire for a motorcycle, in which both ends of a carcass ply consisting of at least one or more cords arranged at an angle of 70 to 85 degrees with respect to the circumferential center line of the tire are wound with a pair of no-heat wires. Here, the ply formed by winding up and folding the bead wire extends to just below the trend joint part, and both ends of the cord overlap each other to form a carcass bonding layer. The width of this solidarity layer Fleet is l when the tread width is taken as TV.
* = Tw~'15TW, which is the opening width of the belt 44r, which is made of a single layer of ply and is located directly below the carcass joint layer at this overlap part. When there are two or more layers, they are contracted in the direction that intersects with each other, and the width of the bottom layer is k3W=T
It is a pneumatic tire with a semi-radial belted structure for motorcycles, which is characterized by a range of W to name TW and B#>R#, and the carcass ply is made of polyester/I/, nylon organic fiber. The material of the cord or cord of the belt layer is a pneumatic tire made of an organic am cord such as polyester, nylon, aromatic polyester, or steel cord.

This will be explained below based on the drawings.

FIG. 2 is a cross-sectional view of a tire according to the present invention. In the figure, tire 1 has sidewall 2. The tread 5 is constructed continuously in a toroidal manner.

The carcass 4 is made up of one ply P-1, and a pair of left and right beads 5 are brought up at both ends of the ply to form a turn nap 4 p-2. A so-called solid layer R continuous in a band-like direction is formed. The width of the solid layer kF+11 is determined to be an arbitrary width within the range of Tread Kyotaichi TW and later Tf-TW at ℃ in consideration of the belt layer width and tire size, the model to which the tire is installed, the required characteristics, etc., which will be described later. Of course, the rigidity of the ground contact area increases in proportion to the RW size, and the lateral rigidity also improves, so the steering stability of the console is affected, but ultimately the tread pattern rigidity and belt layer The rigidity of these elements exerts a mutually effective effect, so by appropriately combining these six elements, the rigidity of the tread crown is highest, and the rigidity gradually decreases as it approaches the shank. Set. If there is a rigidity fault in the lateral direction of the ground contact surface, as mentioned above, it will affect the maneuverability of the motorcycle when turning with a large camper attached (it will not cause a fatal problem). .

The carcass ply WIB-1 is in a state where one of the joint r111 (carcass ply P-1) is searched, has an inclination angle of 0 to 50 degrees with respect to the tire circumferential center -10, and has 4J! several layers. The blades are arranged so as to intersect with each other.The width Bd of the belt is a width that is consistent with the width RW of the solid layer and the width TW of the belt Vy, so that the ends of each belt are mutually crossed. BW=T#-area TW and B so as not to meet each other again.
#) The room shall be located at the end of the FIW range. The effect of arranging the belt layer below and adjacent to the connection layer R as in the present invention is that the movement of the belt layer is protected and restricted by the folded braai made by winding up the peed wire, so that the movement of the belt layer is protected and restricted. Even when the belt 711 rotates with a large camper angle, the belt layer follows the movement of the carcass ply, and the end of the belt 711 does not rise above the carcass layer and come loose as in the conventional structure. Therefore, since the rigidity always changes integrally with the carcass layer, faults are not formed, and this is the reason why it provides an effect to the maneuverability of the tercycle that was not seen in conventional structures.

Also, the cord of carcass ply 4 is made of organic fiber cord such as polyester or nylon, and is used as a belt.

The cords of the layers are polyester, nylon, aromatic polyamide fiber cords or steel cords. Of course, it is also possible to combine these belt materials. example is,
The first belt is made of steel, and the second belt is combined with nylon cord.

Regarding the prototype tire configured as described above, a test M with a bias tire (C Comparative Example-1) and a radial tire (Comparative Example-2) of conventional structure will be described below.

The tire size for both the front and rear wheels was 4.00-1041, and the tread shown in the pattern development diagram in FIG. 6 was shared by the embodiment of the present invention and the comparative example of the conventional structure. The main components of these test tires are shown in Table 1.

The test results are shown in Table 2. The values in the table are expressed as an index when Comparative Example 1 is taken as 100, and it can be seen that the larger llα is better regardless of which characteristic it is. Become.

Table 2 The above test results are explained as follows.

1) Steering stability Front and rear tires 4.00-10 4PR tires (inner pressure is Freon) 2.2 LJ/d, IJ Kya, 4 groan/, d, actual vehicle feeling test (stability, maneuverability) was conducted by six test drivers, and the results were compiled using a five-point evaluation method.

2] Copper abrasiveness One round 5.5 & 1so at an average speed of 12 obA
The vehicle was run on an OKJ truck and the remaining crown groove was measured and evaluated. The internal pressure at this time was 2, b/d.

5) High speed durability Internal pressure 2.5 groans/' + load 250 to 4 on a steam drum with a smooth surface of 1.6 m in diameter 100
If you start from h/hQ altitude and drive for 30 minutes without any abnormality, 1
Increase the speed by 0hZh and sex for 60 minutes each. And the tires were evaluated at 10 degrees, which was the first chapter.

As detailed above, the semi-radial tire for motorcycles according to the present invention not only provides superior maneuverability compared to conventional radial tires, but also has better wear resistance and high-speed durability than conventional radial tires. It can be seen that it is superior to bias tires.

These excellent characteristics can be achieved by providing protection by providing a joint layer formed directly under the tread crown center by the turn-up ply unique to the present invention, and a carcass ply closely contacting below this joint layer. , resulting from a belt configuration that restricts its movement.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a conventional bias structure tire, FIG. 2 is a cross-sectional view showing an embodiment of the present invention, and FIG. 2 is a partially enlarged view showing main parts of the crown carcass and belt structure. FIG. 5 is a pattern development diagram of the tire used as a test tire, and FIG. 4 is a rough cross-sectional view of the radial structure tire. 2...Side wall, 6-...Tread. 4...Carcass, 5...Bead, 6...Apex, 11...Groove, 12-...Rib. Figure 1 Figure 2 b Procedural amendment band October 78, 1981 Patent application 2 filed on June 29, 1988, Name of invention ``Motorcycle'', Miracial tire 3, Person making the amendment 4, Amendment order Date of publication 5, subject of amendment 118w Claims column, Detailed description of the invention column 6, lji Correct contents (1) The entire scope of the claims is corrected as shown in the attached sheet. (2) Separate paper, page 6, line 8 from the bottom of the specification Claims (1) A carcass ply consisting of at least one layer in which cords are arranged at an angle of 70 to 85 degrees with respect to the circumferential center line of the tire. In semi-radial tires for motorcycles, both ends of the cord are wound up with a pair of bead wires, and the ply formed by winding up the bead wire and folding it back extends to just below the trailing crown part, and both ends of the cord are overrun 7" l, and the carcass is joined together. The width RW of this joint layer formed by layer R'2 is RW=TW, where TW is the tread width.
~1/, TW, and immediately below this carcass joint layer, a belt layer consisting of one or more plies is placed at an angle of 0 to 30 degrees with respect to the circumferential center line of the tire. The semi-radial type for motorcycles is characterized in that the width BW of the bell) II is in the range TW to TW and BW>RW.
It is a pneumatic tire with a belted structure. (2) The pneumatic tire according to claim 1, wherein the cord of the carcass ply is an organic fiber cord of polyester or nylon. (5) The pneumatic tire according to claim 1, wherein the material of the cord of the heald layer is an organic fiber cord such as polyester, nylon, aromatic poly-L, or steel cord.

Claims (1)

[Claims] it) A motorcycle in which a carcass ply consisting of at least one layer in which cords are arranged at an angle of 70 to 85 degrees with respect to the circumferential center line e of the tire is wound with a pair of bead wires at both ends. For semi-radial tires, the ply formed by winding up and folding the bead wire extends to the toe of the tored crown, and both ends of the cord overlap each other to form the carcass solid layer R. The width of the layer R-flj is the width of FIW = TW-\TV where the tread width is Tlgl, 7, and the belt layer consisting of one or more plies is placed directly under this carcass joint layer. At an angle of 0 to 30 degrees with respect to the circumferential center line of
The present invention is a pneumatic tire with a semi-radial belted structure for a motorcycle, characterized in that the width Bw of the belt layer is in the range of B W = T W - TV and B'W EV. (2) The pneumatic tire according to claim 1, wherein the cord of the carcass ply is an organic VA fiber cord of polyester or nylon. (5) The cord material of the belt layer is an organic fiber cord such as polyester, nylon, aromatic polyester) or
The pneumatic tire according to claim 1, which is a steel cord.