JPH02155807A - Amphibian tire - Google Patents

Abstract

PURPOSE:To enhance the on-ice propulsive force by partitioning the tread with grooves intersecting the equator, thereby forming a plurality of lugs, and also partitioning the tab stretching from the two sides of the tire to the side wall alike with a plurality of grooves. CONSTITUTION:In the tread 18, a plurality of lugs 22 are partitioned with No.1 grooves 20, intersecting the equator 24 of the tire. Each groove 20 has a bend as shown in the center of the tread 18 in its width direction. At both sides of tire in its width direction, No.1 grooves 26 are formed stretching from the grounding surface to the side wall via shoulder, and a plurality of tabs 28 are partitioned. This will enhance the on-ice propulsive force.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a tire that can be used both on water and on land.

(Prior Art) Tires used in all-terrain vehicles that can run on any surface on land are themselves for land use.
Even if the all-terrain vehicle rotates its wheels when traveling on water,
It does not generate the large thrust necessary for propulsion.

(Problems to be Solved) An object of the present invention is to provide an amphibious tire that generates a large thrust necessary for running a vehicle on water.

(Solution Means, Functions and Effects of the Invention) The amphibious tire of the present invention has a plurality of lugs formed in the tread portion at intervals in the tire circumferential direction, and a first lug extending in a direction intersecting the tire equatorial plane. a plurality of lugs separated from each other by grooves; and a plurality of ears, which are located on both sides in the tire width direction and reach from the tread surface of the tread portion to the sidewall portion via the shoulder portion, and which communicate with the first groove. and a plurality of ears separated from each other in the tire circumferential direction by two grooves.

In the tire of the present invention, when the tire is rotated in water, the ears and lugs scratch the water, and therefore, compared to conventional tires, the tire generates a large force necessary for running in water.

The cross-sectional width of the tire is W, and the cross-sectional height of the tire is H1.
The depth dimension of the first groove is D, the width of the r1 part and the lug in the tire circumferential direction is t, and the width from the first edge of the ear part on the tire tread side to the bead part side is 2 mm≦D≦20 mm, where h is the length to the edge of the second edge, and A is the height of the ear at the second edge. It is preferable that 5H≦h≦0.8H, 5mm≦A≦10mm, and 10mm≦t≦15mm.

If D is less than 12 mm, the effect of webbing by the portion defining the first groove of the tread portion will be reduced, resulting in insufficient thrust in water. If D exceeds 20 mm, the amount of rubber will increase, and troubles due to heat generation will be less likely to occur when riding on a land vehicle.

When h is less than 0.5H or A is less than 5 mm,
Since the effectiveness of the water webs by the ears is reduced, the thrust under water is insufficient. When h exceeds 0.8H, it becomes impossible to assemble to the rim.

If A exceeds 10 mm, the gap between the tire and the vehicle becomes too small, making it difficult to mount it on the vehicle.

If t is less than 10 mm, the rigidity of the lug decreases, resulting in large deformation of the lug when traveling on land 1-. t is 1
If it exceeds 5 mm, the heat dissipation effect of the tire will be reduced when driving on land, making the tire more likely to be damaged by heat generation.

(Example) Referring to FIG. 1, a tire 10 includes a pair of annular beet portions 12, a pair of annular sidewall portions 14, a pair of annular shoulder portions 16, and an annular tread portion 18.
and has. The tread portion 18, as shown in FIG.
The tire 10 is divided into a plurality of lugs 22 by a plurality of first grooves 20 spaced apart from each other in the circumferential direction. The first groove 20 extends transversely to the tire equatorial plane 24, or the tread pattern has a symmetrical shape with respect to the tire equatorial plane 24. Therefore, the first groove 20 is formed in the tread portion 18.
It is bent at the center in the width direction.

The tire 10 also has a plurality of ears 28 on both sides of the tire in the width direction and separated from each other in the circumferential direction of the tire by second grooves 26. 1 part 28 reaches the sidewall part 14 from the tread surface 30 of the tread part 18 via the stain part 16.

The inner diameter dimension BD of the tire 10 is 202.4 mm, and the tire 1
The cross-sectional width dimension W of the tire 10 is 184 mm, the cross-sectional height dimension H of the tire 10 is 130 mm, and the depth dimension of the first groove 20 is 18 mm.
mm, the protruding height dimension A of the ear part 28 at the second edge 34 is 7.0 mm, the width dimension TW of the tread surface 30 is 190 mm,
The width t of the ear portion 28 and the lug 22 in the tire circumferential direction is 13 mm, and the length from the first edge 32 of the ear portion 28 on the tread surface 30 side to the second edge 34 of the ear portion 28 on the bead portion 12 side. The dimension can be 80 mm.

However, the dimensions vary depending on the type of tire. In particular, the dimensions H, A, t and h are values that satisfy the following as described above: 12mm≦D≦20mm 0.5H≦h≦0.8H 5mm≦A≦10mm 10mm≦t≦15mm It is preferable that there be.

In the illustrated example, the second edge 34 of the ear portion 28 is located at a position slightly closer to the bead portion 12 than the position where the cross-sectional width dimension W of the tire is at its maximum value, and the second edge 34 of the ear portion 28 is located at a position slightly closer to the bead portion 12 than the position where the cross-sectional width dimension W of the tire is at its maximum value. distance of 1ll
lLW is larger than the cross-sectional width dimension W. Note that the second edge 34 may be located at a position where the cross-sectional width dimension W of the tire is at its maximum value or on the side of the tread surface 30 from this position.

The tire of the present invention (Example 1) in which the dimensions BD, W, H, D, A, TW, h and t were set to the values shown in Table 1, and two types of conventional tires (Comparative Examples 1 and 2) was produced.

The tire of Example 1 has a tread pattern shown in FIG. On the other hand, the tire of Comparative Example 1 is a so-called conventional all-terrain vehicle tire having a tread pattern including a plurality of blocks 36 and recesses between the blocks, as shown in FIG. It has the cross-sectional shape shown in the figure.

Further, the tire of Comparative Example 2 is a so-called brain tire having no tread pattern, and has the cross-sectional shape shown in FIG. The size of each tire is 19X7.00
-8.

Each tire was tested for propulsion on water and running on land. The results are shown in Table 1.

The land driving test uses an all-terrain vehicle and is based on the driver's feeling evaluation.

In the propulsion test on water, as shown in Figure 5, the tire 4
A weight 42 of 100 g is attached to one location on the outer peripheral surface of the tire 40, and the tire 40 is rotatably supported in the tap water 44 so that the axis of rotation of the tire 40 is at the level of the water surface of the tap water 44.
The tire 40 was rotated due to the weight imbalance due to the weight 42 from a position where the weight 42 was approximately 90 degrees with respect to the water surface, the rotation angle α of the tire at that time was measured, and the thrust was evaluated based on the result. Table 1 shows each thrust index when the thrust of the tire of Comparative Example 2 is set to 100. Tire 40 was rotated in the direction of arrow 46 in FIGS. 2 and 3.

In Table 1, the larger the value of the propulsive force, the greater the propulsive force generated underwater, and the larger the value of the running performance, the higher the running performance on land.

As is clear from Table 1, the tires of the examples generate a large propulsive force underwater without significantly impairing running performance on land.

Table-m=-1 /

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of one embodiment of the tire of the present invention;
The figure shows an example of the tread pattern of the tire of the present invention, Figure 3 shows the tread pattern of a conventional tire used for comparison, Figure 4 is its sectional view, and Figure 5. FIG. 2 is a diagram for explaining a method of measuring thrust in water. 10: Tire, 12: Bead part, 14: Sidewall part, 16: Part of shorter, 18 Nidred part, 20: First groove, 26: Second groove,
22: rough, 24 narrowed center, 2 8:
ITJ part, 30: @ surface, 23: first edge, 34: second edge.

Claims (1)

[Scope of Claims] (1) A plurality of lugs formed in the tread portion at intervals in the tire circumferential direction and separated from each other by first grooves extending in a direction intersecting the tire equatorial plane. and,
A plurality of ears located on both sides in the tire width direction and reaching from the tread surface of the tread portion to the sidewall portion via the shoulder portion, and separated from each other in the tire circumferential direction by a second groove communicating with the first groove. An amphibious tire comprising a plurality of ears. (2) The cross-sectional width of the tire is W, the cross-sectional height of the tire is H, the depth of the first groove is D, the width of the ear and the lug in the tire circumferential direction is t, and the The length from the first edge of the ear on the tire tread side to the second edge on the bead side is h, and the height of the ear at the second edge is A. The amphibious tire according to claim 1, wherein: 12mm≦D≦20mm 0.5H≦h≦0.8H 5mm≦A≦10mm 10mm≦t≦15mm.