JP6117556B2 - Construction vehicle tires - Google Patents

Description

  The present invention relates to a tire for a construction vehicle (hereinafter also simply referred to as “tire”), and more particularly to a radial tire for a construction vehicle used for a construction vehicle such as a dump truck used mainly at a construction site or a mine.

  Conventionally, tires having a so-called lug pattern in which a plurality of lug grooves are arranged at predetermined intervals in the tire circumferential direction are widely used as construction vehicle tires used in construction vehicles such as dump trucks. In such construction vehicle tires, in order to improve wear resistance, tread rubber with excellent wear resistance is used, tread volume is increased, deep grooves are used to increase tread gauge, and negative rate is decreased. It is common to use such means as increasing the land rigidity.

  On the other hand, as the tire rim diameter increases, the tire size increases, and the various gauges increase accordingly. If the amount of heat generated by rolling during running increases due to an increase in the rubber volume accompanying the increase in size of the tire, the tire endurance performance decreases as a result of the increase in the internal temperature of the tire. In particular, in the case of a tire used for a vehicle that travels at a relatively high speed, such as a dump truck, a problem arises due to a high calorific value. It is in the tread part and the bead part that the temperature rises. As a technique for lowering the temperature of the tire during running, there is a technique of installing fins (projections) on the outer surface of the tire and cooling with wind from the outer surface side of the tire, but in a large tire of 57 inches or more, Since the total gauge is thick, air cooling only on the outer surface was not sufficient to cool the inside of the tire.

  As a technique related to a tire for a construction vehicle, for example, in Patent Document 1, a plurality of lug grooves are arranged in tread shoulder regions on both sides in the tire width direction, and at least one circumferential groove extending in the tire circumferential direction, and the tire width A plurality of widthwise narrow grooves extending in the direction and intersecting the circumferential grooves and terminating at least at one end in the tread are disposed in the tire center portion, and the tire circumference of the widthwise narrow grooves at the groove bottoms of the circumferential grooves There is disclosed a tire for a construction vehicle in which the groove bottom shape of the circumferential groove is changed in the tire radial direction so that the groove wall heights on both sides in the direction are different from each other.

JP 2007-191093 A (Claims etc.)

  As described above, various problems have been studied in the past regarding wear resistance and heat generation problems in construction vehicle tires. With the recent increase in the level of demand for various performances of tires, major changes have been made to the tire structure. In addition, there has been a demand for the realization of technology for improving the wear resistance and heat dissipation of construction vehicle tires.

  Accordingly, an object of the present invention is to provide a construction vehicle tire capable of solving the above-described problems and improving wear resistance and heat dissipation without significantly changing the tire structure.

  In order to solve the above-described problems, a construction vehicle tire according to the present invention includes a tread portion, a pair of sidewall portions and bead portions extending from both ends of the tread portion, and a toroidal shape between the pair of bead portions. When the extended carcass is used as a skeleton, and six or more belts are provided on the outer side in the tire radial direction of the crown of the carcass, and the six or more belts are sequentially formed as first to sixth belts from the inner side in the tire radial direction, In the construction vehicle tire in which the first belt and the second belt are arranged so as to cross each other at an angle of 80 ° or more with respect to the tire width direction, a cylindrical first space portion extending toward the inside of the tire on the surface of the tread portion When the position where the cylindrical central axis of the first space intersects the outer surface of the tire is the installation position of the first space, the first space The distance A1 in the tire width direction from the tire equatorial plane at the installation position satisfies the relationship represented by 0 <A1 <0.5 × TW with the tread half width TW, and the diameter φ1 of the first space portion is Satisfying the relationship expressed by 0.007 × R <φ1 <0.041 × R with the rim diameter R, the depth D1 along the extending direction of the first space portion is the depth of the first space portion. Satisfying the relationship represented by 0.3 × G1 <D1 <0.8 × G1 with the distance G1 along the extending direction of the first space from the installation position to the carcass line, the first space Extending in the direction from the direction perpendicular to the tire axial direction to the direction perpendicular to the carcass line through the installation position of the first space, and one of the first spaces Part is filled with a rubber material having a modulus at 300% elongation of more than 10 MPa and less than 20 MP. It is an butterfly.

  According to the present invention, by providing the first space portion on the surface of the tread portion where the temperature becomes high during traveling, the high temperature portion inside the tire can be directly in contact with the outside air, and the heat generated in the tread portion can be dissipated. . Therefore, the rise in the tire internal temperature can be suppressed thereby, the tread temperature can be efficiently reduced, and the tire durability performance can be improved. Moreover, the abrasion resistance of the surface of a tread part can be improved by filling the rubber material excellent in abrasion resistance into at least one part of the 1st space part. Furthermore, since the first space portion is provided on the surface of the tread portion, the time required for vulcanization can be shortened even with a thick gauge, which can contribute to an improvement in productivity.

It is a width direction sectional view showing an example of the tire for construction vehicles of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a cross-sectional view in the width direction showing an example of a construction vehicle tire of the present invention. As illustrated, the construction vehicle tire of the present invention includes a tread portion 11 and a pair of sidewall portions 12 and bead portions 13 extending from both ends thereof, and extends in a toroidal shape between the pair of bead portions 13. Carcass 1 is the skeleton. The carcass 1 preferably includes a folded carcass ply wound around the bead core 7 embedded in each of the pair of bead portions 13 from the tire inner side toward the outer side, as illustrated. In addition, six or more belts 6 in the illustrated example of the crown portion of the carcass 1 in the tire radial direction are disposed, and six belts 2 in the illustrated example are arranged in order from the inner side in the tire radial direction. When the sixth belt is used, the first belt 2a and the second belt 2b are arranged so as to cross each other at an angle of 80 ° or more with respect to the tire width direction.

  In the tire of the present invention, a cylindrical first space portion 3 extending toward the inside of the tire is provided on the surface of the tread portion 11. By providing the first space 3, the temperature of the tire inner surface exposed to the outside air is very high, so that the heat inside the tire can be efficiently reduced as compared with the state where only the conventional tire outer surface is air-cooled. It can be transmitted to the outside air, and the increase in tire internal temperature can be suppressed and the tire durability performance can be improved. In addition, although the temperature of the air in the 1st space part 3 once raises by absorbing heat, since the air in the 1st space part 3 is replaced | exchanged one by one with driving | running | working, a high temperature difference with external air and a tire internal surface is high. Thus, the tire cooling effect can be continued throughout the run. Moreover, since the time required for vulcanization can be shortened even if it is a thick gauge by providing the 1st space part 3, it can also contribute to the improvement of productivity. As shown in the figure, the first space 3 can be provided in a cylindrical shape with a bottom surface of a hemispherical surface.

The first space portion 3 is arranged so as to satisfy the following conditions in a cross section in the tire radial direction when the position where the cylindrical central axis intersects the outer surface of the tire is the installation position of the first space portion 3. Has been. First, the extending direction of the first space portion 3 exists from a direction perpendicular to the tire axial direction through the installation position of the first space portion 3 to a direction perpendicular to the carcass line. Further, the distance A1 in the tire width direction from the tire equator surface at the installation position of the first space portion 3 is expressed by the following formula (1) between the tread half-width TW,
0 <A1 <0.5 × TW (1)
It shall satisfy the relationship indicated by. That is, the first space portion 3 is installed in the center region from the ¼ point to the ¾ point of the tread width around the tire equator plane. In the tire having the belt structure as described above, this is usually most in the center region between the ¼ points which are the midpoints between the tread edge and the tire equator when the tread width is divided into four equal parts. This is because the internal temperature of the tire becomes high, and it is necessary to effectively reduce the temperature in this region.

Further, the diameter φ1 of the first space portion 3 is expressed by the following formula (2) with respect to the rim diameter R:
0.007 × R <φ1 <0.041 × R (2)
It shall satisfy the relationship indicated by. If the diameter φ1 of the first space portion 3 is smaller than the above range, the replacement of the air inside the space is less likely to occur, so that the cooling effect is impaired. On the other hand, when the diameter φ1 of the first space portion 3 is larger than the above range, the rigidity of the tread portion is lowered, the collapse deformation is increased, and the distortion generated in the tread portion is increased. However, since the tread portion is a ground contact surface, if the first space portion 3 is installed at the center portion of the tread block, there is almost no reduction in the block rigidity of the tread, and the sliding behavior on the ground contact surface is equivalent. Thus, it is possible to ensure wear resistance equivalent to that before the installation of the first space portion 3.

Furthermore, the depth D1 along the extending direction of the first space portion 3 is expressed by the following formula between the distance G1 along the extending direction of the first space portion 3 from the installation position of the first space portion 3 to the carcass line. (3),
0.3 × G1 <D1 <0.8 × G1 (3)
It shall satisfy the relationship indicated by. Here, the carcass line refers to a center line passing through the thickness center of the carcass 1 in the cross section in the tire width direction. If the depth D1 of the first space portion 3 is smaller than the above range, the distance between the first space portion 3 and the high temperature portion inside the tire is increased, and effective cooling is not performed. On the other hand, if the depth D1 of the first space 3 is larger than the above range, the belt may be exposed to the outside air.

  In the tire of the present invention, at least a part of the first space 3 is filled with a rubber material having a modulus at 300% elongation of more than 10 MPa and less than 20 MP. By filling at least part of the first space portion 3 with such a hard rubber material, an effect of improving the wear resistance can be obtained. In the present invention, the first space portions 3 can be provided at an appropriate pitch at equal intervals in the tire circumferential direction. Moreover, the 1st space part 3 is good also as what is arrange | positioned for every block provided in the tread part surface at appropriate intervals in the tire circumferential direction.

  In the present invention, in addition to the first space portion 3 in the tread portion, in accordance with the following, either or both of the inside of the lug groove provided in the tread portion and the surface of the bead portion It is preferable to provide a space part and / or a third space part. Similarly to the first space portion, the second space portion and the third space portion can be provided in a cylindrical shape with a bottom surface of a hemispherical surface, and the arrangement pitch is also set in the first space. Similarly to the part 3, the tires can be arranged at a predetermined pitch at equal intervals in the tire circumferential direction, or at every groove or block at appropriate intervals in the tire circumferential direction.

  Specifically, the lug groove 4 is provided on the surface of the tread portion 11, and the inside of the tire is disposed in the groove of the lug groove 4 in the shoulder region on the outer side in the tire width direction from the tire equatorial plane to ½ width of the tread half width TW. It is preferable to provide a cylindrical second space portion 5 extending toward. As a result, the same effect of reducing the tire temperature during travel as in the case of providing the first space 3 can be obtained also in the shoulder region. In addition, the installation of the second space portion 5 can more effectively eliminate the deterioration in productivity due to the increase in the vulcanization time accompanying the increase in size of the tire. The vulcanization time of the green tire is usually set in consideration of the degree of vulcanization in the tread portion shoulder region where the gauge is thickest in the tire. This is because the vulcanization speed in the shoulder region is increased because the tire is buried in the tire, and as a result, the vulcanization time can be set short. Therefore, when the second space 5 is provided by cutting or the like on the vulcanized tire, the effect of shortening the vulcanization time cannot be obtained.

The second space portion 5 satisfies the following conditions in the cross section in the tire radial direction when the position where the cylindrical central axis intersects the bottom surface of the lug groove 4 is the installation position of the second space portion 5. It is arranged as follows. First, the extending direction of the second space portion 5 exists between a direction that passes through the installation position of the second space portion 5 and is horizontal to the tire axial direction to a direction that is perpendicular to the carcass line. Further, the distance A2 in the tire radial direction from the tire outer diameter height at the installation position of the second space portion 5 is the outermost layer located on the outermost side in the tire radial direction among the tire cross-section height SH and the six or more belts 2. Between the height H of the belt 2c on the tire equatorial plane, the following formula (4),
SH-H <A2 <0.19 × SH (4)
It shall satisfy the relationship indicated by. If the distance A2 in the tire radial direction of the installation position of the second space portion 5 is outside in the tire radial direction from the above range, the belt end deformation is affected. If the distance A2 in the tire radial direction is outside the above range, the gauge is It will leave | separate from a thick position and an effective cooling effect will no longer be acquired. Here, in the present invention, the tire cross-section height SH refers to a half of the difference between the outer diameter of the unloaded tire and the rim diameter when the tire is mounted on the applicable rim and filled with the prescribed air pressure. Shall. Applicable rims refer to rims defined in the following standards. Specified air pressure refers to the air pressure defined in accordance with the maximum load capacity in the following standards. The maximum mass allowed to be loaded on. The standard is defined by an industrial standard effective in the region where the tire is produced or used. For example, “The Tire and Rim Association Inc. Year Book” in the United States, and “The European Tire and Land” in Europe. It is “Standards Manual” of Rim Technical Organization, and “JATMA Year Book” of Japan Automobile Tire Association in Japan.

In addition, the diameter φ2 of the second space 5 is between the rim diameter R and the following formula (5),
0.007 × R <φ2 <0.024 × R (5)
It shall satisfy the relationship indicated by. If the diameter φ2 of the second space portion 5 is smaller than the above range, the replacement of the air inside the space is less likely to occur, so that the cooling effect is impaired. On the other hand, when the diameter φ2 of the second space portion 5 is larger than the above range, the rigidity of the shoulder region decreases, the collapse deformation increases, and the strain generated in the shoulder region increases.

Furthermore, the depth D2 along the extending direction of the second space portion 5 is expressed by the following formula between the distance G2 along the extending direction of the second space portion 5 from the installation position of the second space portion 5 to the carcass line. (6),
0.3 × G2 <D2 <0.8 × G2 (6)
It shall satisfy the relationship indicated by. If the depth D2 of the second space portion 5 is smaller than the above range, the distance between the second space portion 5 and the high temperature portion inside the tire is increased, and effective cooling is not performed. On the other hand, if the depth D2 of the second space 5 is larger than the above range, the belt may be exposed to the outside air.

  Moreover, in this invention, it is preferable to provide the cylindrical 3rd space part 6 extended toward the inside of a tire on the surface of the bead part 13. As shown in FIG. Even if the outer surface of the tire is cooled, the temperature in the vicinity of the winding portion 1A of the folded carcass ply where the temperature is high and the failure is likely to occur cannot be reduced. Since it can be exposed, the effect of reducing the tire temperature during traveling can be obtained also at the bead portion, similar to the provision of the first space portion 3.

The third space portion 6 is arranged so as to satisfy the following conditions in the cross section in the tire radial direction when the position where the cylindrical central axis intersects the outer surface of the tire is the installation position of the third space portion 6. Has been. First, the extending direction of the third space 6 extends from a direction horizontal to the tire axial direction through the installation position of the third space 6 to a direction perpendicular to the carcass line of the folded-up carcass ply 1A. Exists between. Further, the distance A3 in the tire radial direction from the rim diameter height at the installation position of the third space portion 6 is expressed by the following formula (7) between the tire cross-section height SH,
0.16 × SH <A3 <0.32 × SH (7)
It shall satisfy the relationship indicated by. If the distance A3 in the tire radial direction of the installation position of the third space portion 6 is made lower than the above range in the tire radial direction, the installation position of the third space portion 6 will be closer to the rim, so that it will collapse during load rolling. When the rim flange contacts the opening of the third space 6 at the time of deformation, cracks or the like may occur. On the other hand, if the distance A3 in the tire radial direction of the installation position of the third space portion 6 is made higher in the tire radial direction than the above range, the position where the gauge is thick and the temperature becomes high cannot be cooled effectively.

Further, the diameter φ3 of the third space portion 6 is expressed by the following equation (8) between the rim diameter R and
0.007 × R <φ3 <0.024 × R (8)
It shall satisfy the relationship indicated by. If the diameter φ3 of the third space portion 6 is smaller than the above range, the replacement of the air inside the space is difficult to occur, and the effect of cooling is impaired. On the other hand, when the diameter φ3 of the third space portion 6 is larger than the above range, the rigidity of the bead portion is lowered, the collapse deformation is increased, and the distortion generated in the bead portion is increased.

Furthermore, the depth D3 along the extending direction of the third space portion 6 is along the extending direction of the third space portion 6 from the installation position of the third space portion 6 to the carcass line of the winding portion 1A of the folded carcass ply. The following formula (9) between the distance G3 and
0.3 × G1 <D3 <0.8 × G3 (9)
It shall satisfy the relationship indicated by. If the depth D3 of the third space portion 6 is smaller than the above range, the distance between the second space portion 5 and the high temperature portion inside the tire is increased, and effective cooling is not performed. On the other hand, if the depth D3 of the third space portion 6 is larger than the above range, the rolled-up carcass ply winding portion 1A may be directly exposed to the outside air when assuming variations in the tire case line.

  In the present invention, only the point satisfying the conditions related to the first space part, preferably the second space part and the third space part is important, and thus, a construction vehicle having wear resistance and heat dissipation. Tires can be realized. The tire of the present invention is preferably a radial tire for construction vehicles having a rim diameter of 57 inches or more.

  In addition, for example, the tread pattern formed on the surface of the tread portion 11 in the tire of the present invention may have any groove that can provide the second space portion. This is a so-called lug pattern in which lug grooves are arranged at predetermined intervals in the tire circumferential direction. Furthermore, an inner liner (not shown) is formed in the innermost layer of the tire of the present invention. Furthermore, as the gas filled in the tire of the present invention, normal or air having a changed oxygen partial pressure, or an inert gas such as nitrogen can be used.

Hereinafter, the present invention will be described in more detail with reference to examples.
A tire for a construction vehicle was produced at a tire size of 59 / 80R63 according to the following conditions. This tire was provided with six belts, and when the belts were first to sixth belts sequentially from the inner side in the tire radial direction, the first belt and the second belt were arranged in an interlaced manner. Moreover, the tire cross-section height SH of this tire was 1210 mm, the height H of the outermost layer belt (sixth belt) on the tire equatorial plane was 1120 mm, the tread half-width TW was 1270 mm, and the rim diameter R was 1600.2 mm. Moreover, the lug groove was provided in the surface of the tread part. As for the tire of Example 1, a part of the first space was filled with a rubber material at an equal interval and having a modulus at 300% elongation of 17 MPa.

  Each test tire was evaluated according to the following conditions under normal conditions (internal pressure 600 kPa, load 100 ton, rim width 44 inches) based on TRA. For evaluation of heat generation, after running for 24 hours under normal conditions in accordance with TRA using a drum tester, for tread heat generation, the temperature near the belt is measured with a temperature measuring needle, and for shoulder heat generation, the main carcass is measured. The temperature near the ply was measured and compared. In addition, when the rubber material of the test tire of Experimental Example 2 was filled, the modulus distribution and the past market wear resistance performance were predicted and compared. For bead heat generation, each test tire is attached to the front position of a separate truck, and the same route is run simultaneously to match the usage conditions, and the temperature of the bead portion near the folded carcass ply is used as a temperature gauge. Measured and compared. The results are all indicated by an index with the value in Experimental Example 1 being 100. The smaller the exothermic index, the lower the temperature and the better. The larger the wear resistance index, the better the wear resistance. These results are also shown in the table below.

＊１）Ａ１：第一空間部の設置位置のタイヤ赤道面からのタイヤ幅方向の距離である。（０．５×ＴＷ＝６３５ｍｍ），＊２）Ｄ１：第一空間部の延在方向に沿う深さである。（０．３×Ｇ１＝３９ｍｍ、０．８×Ｇ１＝１０４ｍｍ），＊３）Ｇ１：第一空間部の設置位置からカーカスラインまでの第一空間部の延在方向に沿う距離である。＊４）φ１：第一空間部の径である。（０．００７×Ｒ＝１１．２ｍｍ、０．０４１×Ｒ＝６５．６ｍｍ），＊５）Ａ２：第二空間部の設置位置のタイヤ外径高さからのタイヤ半径方向の距離である。（ＳＨ−Ｈ＝９０ｍｍ、０．１９×ＳＨ＝２２９．９ｍｍ），＊６）Ｄ２：第二空間部の延在方向に沿う深さである。（０．３×Ｇ２＝３０ｍｍ、０．８×Ｇ２＝８０ｍｍ），＊７）Ｇ２：第二空間部の設置位置からカーカスラインまでの第二空間部の延在方向に沿う距離である。＊８）φ２：第二空間部の径である。（０．００７×Ｒ＝１１．２ｍｍ、０．０２４×Ｒ＝３８．４ｍｍ），＊９）Ａ３：第三空間部の設置位置のビードベースラインＢＬからのタイヤ半径方向の距離である。（０．１６×ＳＨ＝１９３．６ｍｍ、０．３２×ＳＨ＝３８７．２ｍｍ），＊１０）Ｄ３：第二空間部の延在方向に沿う深さである。（０．３×Ｇ３＝２５．５ｍｍ、０．８×Ｇ３＝６８ｍｍ），＊１１）Ｇ３：第三空間部の設置位置から折返しカーカスプライの巻上げ部のカーカスラインまでの第三空間部の延在方向に沿う距離である。＊１２）φ３：第二空間部の径である。（０．００７×Ｒ＝１１．２ｍｍ、０．０２４×Ｒ＝３８．４ｍｍ），＊１３）タイヤ外表面における第一空間部の設置位置を通りカーカスラインに対し垂直な方向である。＊１４）溝の底面における第二空間部の設置位置を通りカーカスラインに対し垂直な方向である。＊１５）タイヤ外表面における第三空間部の設置位置を通り折返しカーカスプライの巻上げ部のカーカスラインに対し垂直な方向である。

* 1) A1: A distance in the tire width direction from the tire equator plane at the installation position of the first space portion. (0.5 × TW = 635 mm), * 2) D1: Depth along the extending direction of the first space. (0.3 × G1 = 39 mm, 0.8 × G1 = 104 mm), * 3) G1: A distance along the extending direction of the first space portion from the installation position of the first space portion to the carcass line. * 4) φ1: The diameter of the first space. (0.007 × R = 11.2 mm, 0.041 × R = 65.6 mm), * 5) A2: Distance in the tire radial direction from the height of the tire outer diameter at the installation position of the second space. (SH-H = 90 mm, 0.19 × SH = 229.9 mm), * 6) D2: Depth along the extending direction of the second space. (0.3 × G2 = 30 mm, 0.8 × G2 = 80 mm), * 7) G2: Distance along the extending direction of the second space portion from the installation position of the second space portion to the carcass line. * 8) φ2: The diameter of the second space. (0.007 × R = 11.2 mm, 0.024 × R = 38.4 mm), * 9) A3: Distance in the tire radial direction from the bead base line BL at the installation position of the third space. (0.16 × SH = 193.6 mm, 0.32 × SH = 387.2 mm), * 10) D3: Depth along the extending direction of the second space. (0.3 × G3 = 25.5 mm, 0.8 × G3 = 68 mm), * 11) G3: Extension of the third space portion from the installation position of the third space portion to the carcass line of the turned-up portion of the folded carcass ply The distance along the current direction. * 12) φ3: The diameter of the second space. (0.007 × R = 11.2 mm, 0.024 × R = 38.4 mm), * 13) A direction perpendicular to the carcass line passing through the installation position of the first space on the outer surface of the tire. * 14) A direction perpendicular to the carcass line passing through the installation position of the second space on the bottom surface of the groove. * 15) It is a direction perpendicular to the carcass line of the winding portion of the carcass ply passing through the installation position of the third space portion on the outer surface of the tire.

  As shown in the above table, in the test tire of Experimental Example 2 in which the first space portion is provided on the surface of the tread portion and at least a part thereof is filled with a predetermined rubber material, the tire structure is significantly changed. It was confirmed that the wear resistance could be improved and the heat dissipation could be improved.

DESCRIPTION OF SYMBOLS 1 Carcass, 1A Folding part of folded carcass ply, 2 belt, 2a 1st belt, 2b 2nd belt, 2c outermost layer belt, 3 1st space part, 4 lug groove, 5 2nd space part, 6 3rd space part , 7 Bead core, 11 Tread part, 12 Side wall part, 13 Bead part

Claims (3)

A tread portion and a pair of sidewall portions and bead portions extending from both ends of the tread portion, and a carcass extending in a toroidal shape between the pair of bead portions is used as a skeleton, and the crown portion of the carcass in the tire radial outside 6 or more belts, and when the six or more belts are sequentially designated as the first to sixth belts from the inner side in the tire radial direction, the first belt and the second belt are at an angle of 80 ° or more with respect to the tire width direction. In construction vehicle tires that are crossed with each other,
A surface of the tread portion has a cylindrical first space portion extending toward the inside of the tire, and the first space portion is positioned at a position where the cylindrical central axis of the first space portion intersects the tire outer surface. When the position is set, the distance A1 in the tire width direction from the tire equatorial plane at the installation position of the first space portion in the tire radial cross section is expressed by the following formula (1) between the tread half width TW and the following formula (1):
0 <A1 <0.5 × TW (1)
The diameter φ1 of the first space portion satisfies the following relationship (2) with the rim diameter R:
0.007 × R <φ1 <0.041 × R (2)
The distance G1 along the extending direction of the first space portion from the installation position of the first space portion to the carcass line is the depth D1 along the extending direction of the first space portion. The following formula (3),
0.3 × G1 <D1 <0.8 × G1 (3)
And the extending direction of the first space portion exists between the direction perpendicular to the tire axial direction through the installation position of the first space portion and the direction perpendicular to the carcass line. and, and, a tire for a construction vehicle which part is, modulus at 300% elongation is characterized in that it is filled with a rubber material is less than 20MP exceed 10MPa of said first space. A cylindrical shape having a lug groove formed on the surface of the tread portion and extending toward the inside of the tire in the groove of the lug groove in the shoulder region on the outer side in the tire width direction from the tire equatorial plane to a half width of the tread half width TW. When the position where the cylindrical central axis of the second space intersects the bottom surface of the lug groove is the installation position of the second space, The outermost layer belt tire in which the distance A2 in the tire radial direction from the tire outer diameter height at the installation position of the second space portion is the tire cross-section height SH and the outermost belt in the tire radial direction among the six or more belts. The following formula (4) between the height H on the equator plane,
SH-H <A2 <0.19 × SH (4)
The diameter φ2 of the second space portion satisfies the following relationship (5) with the rim diameter R:
0.007 × R <φ2 <0.024 × R (5)
The distance G2 along the extending direction of the second space portion from the installation position of the second space portion to the carcass line is the depth D2 along the extending direction of the second space portion. And the following formula (6),
0.3 × G2 <D2 <0.8 × G2 (6)
And the extending direction of the second space portion passes through the installation position of the second space portion and extends from a direction horizontal to the tire axial direction to a direction perpendicular to the carcass line. The construction vehicle tire according to claim 1, which is present in claim 1. The carcass includes a folded carcass ply wound around a bead core embedded in each of the pair of bead portions from the inside to the outside of the tire, and a cylindrical first extending toward the inside of the tire on the surface of the bead portion. When the third space portion has a three-space portion, and the position where the cylindrical central axis of the third space portion intersects the outer surface of the tire is the installation position of the third space portion, the third space portion The distance A3 in the tire radial direction from the height of the rim diameter at the installation position of the tire is between the tire cross-section height SH and the following formula (7):
0.16 × SH <A3 <0.32 × SH (7)
In which the diameter φ3 of the third space portion is equal to the rim diameter R by the following formula (8),
0.007 × R <φ3 <0.024 × R (8)
The depth D3 along the extending direction of the third space portion is the third space portion from the installation position of the third space portion to the carcass line of the turned-up portion of the folded carcass ply. The following formula (9) between the distance G3 along the extending direction of
0.3 × G3 <D3 <0.8 × G3 (9)
And the carcass line of the winding portion of the folded carcass ply from the direction in which the extending direction of the third space portion passes through the installation position of the third space portion and is horizontal to the tire axial direction. The construction vehicle tire according to claim 1, wherein the tire is present in a direction perpendicular to the direction.

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