JP2013095334A - Tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire capable of positively preventing generation of ruggedness on an inner face and a side part due to uneven waving of a belt inserted into the tire, improving flexibility in tire design, and exerting performance responding to application.SOLUTION: The tire is provided with a tire case having a lug adhering face, and a plurality of lug members formed individually from the tire case and disposed on the lug adhering face. The plurality of lug members is configured to include at least two or more types of lug members with different rubber qualities.

Description

  The present invention relates to a tire, and more particularly, to a tire case and a tire provided with a plurality of lug members formed separately from the tire case.

Conventionally, as a tire adopted for agricultural vehicles used in wetlands and fragile land, or construction vehicles that frequently travel on rough terrain, from the viewpoint of obtaining high traction, the tread part A lug-equipped tire having a plurality of lugs formed at a predetermined interval along the tire rotation direction (circumferential direction) has become widespread. When manufacturing a tire with a lug, an unvulcanized green tire having a carcass layer laminated in a toroidal shape on a pair of bead portions, a tread rubber layer with a belt inserted therein, etc., has a predetermined shape corresponding to the lug. It is common to perform vulcanization molding by putting in a vulcanizing apparatus provided with a mold having a recess.
The green tire put into the vulcanizer is heated in a state where the surface of the tread rubber layer is pressed to the mold side by a pressing means called a bladder, and a plurality of predetermined shapes in which the tread rubber layer is formed on the mold. By flowing into the recesses, a lug-equipped tire having a plurality of lugs protruding at predetermined intervals from each other along the tire rotation direction is formed.

WO 2009/072633 A1

However, in the above manufacturing method, a part of the rubber forming the tread rubber layer flows into the plurality of recesses formed in the mold during heating. There is a concern that the belt to be inserted is pulled into the recess and vulcanized and molded in a state where the belt is unevenly undulated, resulting in irregularities in the inner surface and side portions of the tire after vulcanization. ing.
In addition, in the above manufacturing method, the rubber body between the lugs is freely formed because a part of the rubber of the tread rubber layer flows into the mold so that the tire body and lugs of the tire with lugs are integrally molded. It is difficult to design the lug-equipped tires according to various applications such as tires with higher traction performance, and it is impossible to arbitrarily set the lug formation location and the inclination angle with respect to the circumferential direction, etc. Met.

  The present invention was made in order to solve the above-mentioned problem, and the belt inserted in the tire is in a non-uniformly wavy state, reliably preventing unevenness on the inner surface and the side part, Provided is a tire capable of improving the degree of freedom in tire design and exhibiting performance according to the application.

As a configuration of a tire for solving the above problems, a tire case having a lug application surface, and a plurality of lug members formed separately from the tire case and disposed on the lug application surface, the plurality of lug members, The tire includes at least two types of lug members having different rubber properties.
According to this configuration, since the lug member is formed separately from the tire case, it is possible to surely prevent the inner surface and the side portion of the tire from being uneven due to the undulation of the belt inserted into the tire. .
In addition, since the lug member and the tire case are individually formed, the shape of the tire case itself and the shape of the lug member itself can be individually set, and the lug member is attached to the lug of the tire case. The position (pitch) at the time of arranging on the sticking surface and the inclination angle with respect to the circumferential direction can be easily changed, and the degree of freedom in designing the tire can be improved.
In addition, since the plurality of lug members arranged on the tire case include two or more types of lug members having different rubber properties, it is possible to obtain a tire that exhibits sufficient performance depending on the use environment and application. .
The summary of the invention does not enumerate all necessary features of the present invention, and sub-combinations of these feature groups can also be the invention.

It is a perspective view which shows a tire with a lug and a lug member. It is width direction sectional drawing which shows a tire case and a lug member. It is sectional drawing which shows a vulcanizer. It is a perspective view which shows the formation pattern of a lug.

  Hereinafter, the present invention will be described in detail through embodiments, but the following embodiments do not limit the invention according to the claims, and all combinations of features described in the embodiments are included. It is not necessarily essential for the solution of the invention.

FIG. 1 is a perspective view showing a lug-equipped tire 10 and a lug 15 included in the lug-equipped tire 10.
In FIG. 1, a lug-equipped tire 10 is roughly formed of a plurality of tire body portions 11 that form the foundation of the tire and a plurality of outer circumferential surfaces 11A of the tire body portions 11 that are spaced apart from each other by a predetermined distance along the circumferential direction. And a lug 15.
The tire with a lug 10 in the present embodiment vulcanizes a vulcanized tire case 21 corresponding to the tire body 11 and a vulcanized lug member 25 corresponding to the lug 15 via a cushion rubber 30 described later. It is formed by integrating in the device. Hereinafter, the structure of the tire case 21 and the lug member 25 in the present embodiment will be described with reference to FIGS. 1 and 2.

FIG. 2 is a cross-sectional view in the width direction when the tire case 21 and the lug member 25 are integrated.
As shown in the figure, the tire case 21 is generally folded around the pair of bead cores 12; 12 and extends between the bead cores 12; 12 in a toroidal shape to form a side portion Ts and a tread portion Tt. A carcass ply 13, a belt 14 laminated on the carcass ply 13 in the tread portion Tt, and an outermost rubber 16 positioned radially outward. The carcass ply 13 and the belt 14 are formed by embedding organic fibers and steel cords in an unvulcanized rubber sheet, and the material, the number of sheets, and the like can be appropriately selected according to the type of tire to be manufactured. . For convenience of explanation, the tread portion Tt and the side portion Ts are defined. However, the range of the tread portion Tt and the side portion Ts varies depending on the use, type, size, and the like of the tire, and is set in a further subdivided region. It is also possible to do.

As shown in FIGS. 1 and 2, the lug member 25 is a member having a substantially trapezoidal cross section along the width direction of the tire case 21 and corresponding to the outer peripheral surface 11 </ b> A of the tire main body 11. The case 21 is disposed so as to protrude radially outward from the outer peripheral surface of the case 21. In addition, the non-treading surface 26 facing the outer peripheral surface of the tire case 21 in the lug member 25 is formed as a curved surface that gently curves corresponding to the surface shape of the tire case 21, and cushion rubber is provided on the lug attaching surface 21 </ b> A of the tire case 21. 30. The lug attaching surface 21A and the cushion rubber 30 will be described later.
Further, the tread surface 27 of the lug member 25 is a surface that comes into contact with the road surface, and is a surface that gradually inclines inward in the radial direction from the vicinity of the center of the tire case 21 to the shoulder side in a state of being integrated with the tire case 21. It is formed. In addition, the whole shape of the lug member 25 is not restricted to the said example, According to the kind and application of the tire used as manufacture object, it can change suitably.

Hereinafter, the manufacturing method of the tire 10 with a lug is demonstrated. The lug-equipped tire 10 is manufactured through an outline, a cutting process, a lag attaching process, and a vulcanizing process.
As shown in FIG. 2 (a), the vulcanized tire case 21 is used in a cutting process to remove, for example, the outer peripheral surface of a new tire case that has been vulcanized and molded in advance or the lug of a used tire by a cutting device not shown. It is formed by cutting. Of the outer peripheral surface of the tire case 21 that has undergone the cutting process, a lug attaching surface 21A is formed at a position where the vulcanized lug member 25 is attached. The lug attaching surface 21 </ b> A is formed with a predetermined interval along the circumferential direction of the tire case 21. The lug application surface 21A is a surface on which the lug member 25 can be applied, and is roughened so that an unvulcanized cushion rubber 30 described later can be easily fixed.

The tire case 21 on which the lug sticking surface 21A is formed is conveyed to the lug sticking step. In the lug pasting step, an unvulcanized cushion rubber 30 is disposed on the lug pasting surface 21 </ b> A of the tire case 21. The cushion rubber 30 is, for example, a plate-like rubber member molded into a shape substantially the same as the shape of the lug member 25 on the non-treading surface 26 side. By arranging the cushion rubber 30 on the lug attaching surface 21A, the tire case 21 and a lug member 25 described later are preliminarily integrated by the adhesive force of the cushion rubber 30.
In the present embodiment, the cushion rubber 30 is described as being disposed on the lug application surface 21A. However, after the cushion rubber 30 is applied to the non-treading surface 26 side of the lug member 25, the cushion rubber 30 is applied. The lug member 25 may be disposed on the lug attaching surface 21A.

  When the arrangement of the cushion rubber 30 is completed, the plurality of lug members 25 vulcanized and molded in advance are pasted on the lug pasting surface 21A via the cushion rubber 30 described above. The lug members 25 are arranged at a predetermined interval along the circumferential direction so as to correspond to the lug attaching surface 21A formed on the tire case 21, and are preliminarily separated from the tire case 21 by the adhesive force of the cushion rubber 30. Integrated.

FIG. 2B is a cross-sectional view in the width direction when the tire case 21 and the lug member 25 preliminarily integrated via the cushion rubber 30 are put into the envelope 31. Hereinafter, the vulcanization process will be described.
The tire case 21 and the lug member 25 that are preliminarily integrated through the lag attaching step are conveyed to the vulcanization step. The vulcanization step is a step in which the tire case 21 and the plurality of lug members 25 that are preliminarily integrated by vulcanizing the unvulcanized cushion rubber 30 are firmly coupled and integrated.
In the vulcanization step, first, the tire case 21 and the lug member 25 that are preliminarily integrated via the cushion rubber 30 are put into the envelope 31. The envelope 31 is a bag body that can be worn from the outer periphery of the tire case 21 and the lug member 25, and the non-treading surface 26 of the lug member 25 is reduced by sucking and reducing the internal air while the envelope 31 is sealed. Press against the lug attaching surface 21A of the tire case 21.

The tire case 21 and the lug member 25 thrown into the envelope 31 are carried into a vulcanizing device called a vulcanizing can (not shown) and vulcanized in a state where a predetermined pressure and heat are applied. The cushion rubber 30 during vulcanization gradually melts as the temperature inside the vulcanization can rises. Thereby, the lug sticking surface 21A of the tire case 21 and the non-treading surface 26 of the lug member 25 are cross-linked and firmly bonded.
When vulcanization for a predetermined time is completed under a predetermined pressure and temperature, the tire case 21 and the lug member 25 are integrated by a crosslinking reaction of the cushion rubber 30, and a product that can exhibit performance as a product after a cooling time. The lug tire 10 as a tire is completed.

As described above, a plurality of vulcanized lug members 25 are individually arranged along the circumferential direction of the lug attaching surface 21A of the vulcanized tire case 21 and integrated via the cushion rubber 30. Therefore, the belt 14 inserted in the tire case 21 does not wave during vulcanization, and it is possible to reliably prevent the unevenness on the inner surface and the side portion Ts of the lug-equipped tire 10 as a product.
In addition, the tire case 21 and the lug member 25 are individually vulcanized and molded in advance, so that the shape of the tire case 21 and the lug member 25 and the position when the lug member 25 is disposed on the lug attaching surface 21A of the tire case 21 are arranged. In addition, the inclination angle can be freely set, and the degree of freedom in designing the tire can be improved. As an example, by setting the thickness of the outermost rubber 16 of the tire case 21 to be thinner than usual, heat generated in the lug-equipped tire 10 during rotation (use) can be easily released to the outside. It becomes possible.

The manufacturing method of the tire 10 with a lug is not restricted to the said embodiment. Hereinafter, the other manufacturing method of the tire 10 with a lug is demonstrated.
FIG. 3 is a cross-sectional view of a vulcanizing device 40 that vulcanizes and bonds the tire case 21 ′ and the lug member 25. The lug-equipped tire 10 according to the present embodiment is different from the above-described embodiment in that an unvulcanized tire case 21 ′ is vulcanized and bonded in a vulcanizer 40. That is, the lug-equipped tire 10 in the present embodiment is obtained by vulcanizing and bonding the lug member 25 vulcanized and molded in advance to the lug attaching surface 21A ′ of the unvulcanized tire case 21 ′. Is molded.

  In FIG. 3, the vulcanizing apparatus 40 is schematically shown as a lower platen 41, a lower mold 42, a lower bead ring 43, an upper mold 44, an upper platen 45, an upper bead ring 46, a bladder 47, a tread mold 48, and a tread segment 49. , An outer ring 50, a stationary platen 51, and an elevating mechanism 52.

  The lower platen 41 is an annular plate body, and has a flow path 41A through which a heating medium such as high-temperature and high-pressure steam or liquid is supplied from a heat source supply device (not shown). The channel 41A is an annular channel formed at a position corresponding to the lower side portion Ts of the tire case 21 ′. The lower platen 41 functions as a heat source that heats the lower side portion Ts mainly through the lower mold 42 positioned above.

  A lower mold 42 is disposed on the upper surface side of the lower platen 41. The lower mold 42 is an annular metal body made of, for example, aluminum, and transfers heat from the lower platen 41 as a heat source located below to the tire case 21 ′. The inner peripheral surface facing the lower side portion Ts of the tire case 21 ′ in the lower mold 42 is formed as a die-attached surface 42A. The die-attached surface 42A is a surface that is curved so as to surround the lower side portion Ts of the tire case 21 '.

  A detachable lower bead ring 43 is attached to the upper side of the lower mold 42. The lower bead ring 43 is an annular body that mainly molds the periphery of the bead core 12 in the tire case 21 ′ and holds a later-described bladder 47 through a grip portion.

  The upper mold 44 is an annular metal body that forms a pair with the lower mold 42, and transfers heat from the upper platen 45 as a heat source located above to the tire case 21 '. An inner peripheral surface of the upper mold 44 that faces the upper side portion Ts of the tire case 21 ′ is formed as a die-attached surface 44 </ b> A. The die-attached surface 44A is a surface curved so as to surround the upper side portion Ts of the tire case 21 '.

  An upper platen 45 is disposed on the upper side of the upper mold 44. The upper platen 45 is arranged in parallel so as to form a pair with the lower platen 41, and can be moved up and down by an elevating mechanism 52, and can be moved up and down with respect to the lower platen 41. Similarly to the lower platen 41, the upper platen 45 is an annular plate, and has a flow path 45A through which a high-temperature and high-pressure vulcanization medium is supplied from a heat source supply device (not shown) during vulcanization. The channel 45A is an annular channel formed at a position corresponding to the upper side portion Ts of the tire case 21 ′. The upper platen 45 functions as a heat source that heats the upper side portion Ts mainly through the upper mold 44 positioned below.

  A detachable upper bead ring 46 is attached to the lower side of the upper mold 44. The upper bead ring 46 is paired with the lower bead ring 43, and is an annular body that holds the mold around the bead core 12 and the bladder 47.

The bladder 47 held by the lower bead ring 43 and the upper bead ring 46 is an elastic bag-like rubber body and is disposed so as to be in close contact with the inner peripheral surface of the tire case 21 '.
A high-temperature and high-pressure heating medium is supplied to the bladder 47 from a heat source supply device (not shown) during vulcanization. When the heating medium is supplied, the bladder 47 expands outside in the tire case 21 ′ while closely adhering along the inner peripheral surface of the tire case 21 ′. As a result, the tire case 21 ′ disposed in the vulcanization space formed by the lower mold 42, the lower bead ring 43, the upper mold 44, the upper bead ring 46, and a tread mold 48 described later, As the bladder 47 expands, the lower mold 42, the lower bead ring 43, the upper mold 44, the upper bead ring 46 and the tread mold 48 are heated while being pressed, and are fitted in the recess 55 of the tread mold 48 in advance. The lug member 25 is vulcanized and bonded.

The tread mold 48 is an annular metal body that is located radially outside the lower mold 42 and the upper mold 44, and is a mold that is individually held with respect to the tread segments 49 that are radially divided equally. is there. The tread mold 48 transmits heat generated from the flow path 50A of the outer ring 50 to the tread portion Tt side of the tire case 21 ′.
On the inner peripheral surface of each tread mold 48, a die-attached surface 48 </ b> A that faces the outer peripheral surface of the tire case 21 ′ and one or a plurality of recesses 55 into which the vulcanized lug member 25 is fitted are formed. . The number of the recesses 55 can be set as appropriate depending on the interval between the lug members 25.
The die-attached surface 48A is a surface extending from the end in the width direction of the tread portion Tt to the center position in the width direction. The die-attached surface 48A is formed as a curved surface so as to surround the outer peripheral surface of the tire case 21 ', and is a surface that forms the outer peripheral surface 11A of the tire main body 11 after vulcanization is completed.

  The recess 55 is a groove that is recessed radially outward from the die surface 48A facing the outer peripheral surface of the tire case 21 ', and has a space that substantially matches the shape of the lug member 25 that has been vulcanized and formed in advance. . The concave portion 55 can be fitted with the vulcanized lug member 25 that has been pre-cured. When the lug member 25 is fitted into the concave portion 55, the surface of the lug member 25 is in close contact with each surface that forms the concave portion 55. It will be surrounded by.

  A plurality of tread segments 49 corresponding to the respective tread dies 48 are arranged on the outer side in the radial direction from the plurality of tread dies 48. The tread segment 49 is a fixing member for the tread mold 48 that is radially divided along the circumferential direction. The tread segment 49 is located between the tread mold 48 and an outer ring 50 to be described later, and is movable on the lower platen 41 in the radial direction. The outer peripheral surface of the tread segment 49 is formed as an inclined surface 49A that is gradually inclined inward in the radial direction from below to above. The inclined surface 49A is formed as a tapered surface facing an inclined surface 50B of the outer ring 50 described later.

  The outer ring 50 is an annular body having a lower opening that extends perpendicularly to the stationary platen 51 fixed to the elevating mechanism 52 so as to surround the upper mold 44 and the upper platen 45 from the outside in the radial direction. Similar to the lower platen 41 and the upper platen 45, the outer ring 50 has a flow path 50A through which a high-temperature and high-pressure vulcanization medium is supplied from a heat source supply device (not shown) during vulcanization. The flow path 50 </ b> A is an annular flow path formed at a position corresponding to the tread portion Tt and the lug member 25 of the tire case 21 ′. The flow path 50A mainly functions as a heat source for heating the tread portion Tt via the tread mold 48 located on the radially inner side.

Further, the inclined surface 50B facing the inclined surface 49A of the tread segment 49 in the outer ring 50 is formed as an inversely tapered surface that gradually inclines radially outward from above.
That is, the inclined surface 49 </ b> A and the inclined surface 50 </ b> B are inclined surfaces having the same gradient, and the elevating mechanism 52 starts to descend along with the vulcanization start operation, and the outer surface is integrally attached via the fixed platen 51. When the inclined surface 50B of the ring 50 is in sliding contact with the inclined surface 49A of the tread segment 49, the plurality of tread segments 49 are radially reduced in diameter, and the tread mold 48 surrounds the outer peripheral surface of the tire case 21 '. It becomes. On the other hand, when the vulcanization is completed and the elevating mechanism 52 starts to rise, the plurality of tread segments 49 are expanded radially outward, and the tire case 21 ′ is released from the tread mold 48 to complete the vulcanization. The rear lug-equipped tire 10 can be removed.

  The elevating mechanism 52 is a cylinder that is located in the center of the vulcanizing apparatus 1 in the radial direction and has a piston inside. The elevating mechanism 52 extends through the fixed platen 51 to the upper platen 45. A movable plate 53 is connected to the lower end of the lifting mechanism 52. The movable plate 53 is a plate that extends in the same direction as the fixed platen 51, and is attached to the lower end of the lifting mechanism 52. Both end portions of the movable plate 53 are connected to the annular upper platen 45. As a result, the upper mold 44, the upper platen 45, and the outer ring 50 connected to the fixed platen 51 are integrally moved up and down by the lifting and lowering operation of the lifting mechanism 52, and the lower platen 41 and the lower mold 42 positioned below are moved up and down. Can be approached or separated.

As described above, when the plurality of tread segments 49 are reduced in diameter as the outer ring 50 is lowered, the tread mold 48 fixed to each tread segment 49 surrounds the circumferential direction of the tire case 21 ′. A sealed vulcanization space is formed by the plurality of tread molds 48, the lower mold 42, the lower bead ring 43, the upper mold 44, and the upper bead ring 46.
The unvulcanized tire case 21 ′ accommodated in the vulcanization space and the vulcanized lug member 25 fitted in the recess 55 in advance are supplied from the lower platen 41, the upper platen 45 and the outer ring 50. The vulcanization gradually proceeds by the heat generated, and a plurality of lug members 25 in contact with the lug attaching surface 21A ′ of the tire case 21 ′ are vulcanized and bonded along the circumferential direction of the tire case 21 ′. The lug-equipped tire 10 in which the tire case 21 ′ and the lug member 25 are integrated can be obtained.

  As described above, a plurality of vulcanized lug members 25 are vulcanized and bonded to the lug sticking surface 21A ′ existing along the circumferential direction on the outer circumferential surface of the unvulcanized tire case 21 ′. However, the belt 14 inserted in the tire case 21 ′ does not wave during vulcanization, and it is possible to surely prevent the inner surface of the lug-equipped tire 10 and the side portion Ts from being uneven.

  In the above-described manufacturing method, an example in which the unvulcanized tire case 21 'and the vulcanized lug member 25 are vulcanized and bonded by the vulcanizer 40 is described as an example, but the present invention is not limited to this. . For example, a vulcanized tire case 21 and an unvulcanized lug member may be disposed in the vulcanizing device 40 and vulcanized and bonded. Moreover, it is good also as a form which arrange | positions the unvulcanized tire case 21 'and the unvulcanized lug member in the vulcanizer 40, and carries out vulcanization adhesion.

FIG. 4 is an enlarged perspective view showing the tire body 11 and the lug 15. Hereinafter, the pattern of the lug 15 formed on the outer peripheral surface 11A of the tire main body 11 and the inclination angle of the lug 15 with respect to the circumferential direction will be described.
4A is an enlarged perspective view showing the lug 15 of the lug-equipped tire 10 in FIG. 1, and is shown for comparison with other formation patterns of the lug 15 described later. As shown in the figure, a plurality of lugs 15A corresponding to the lugs 15 shown in FIG. 1 are formed on the outer peripheral surface 11A of the tire body 11 along the circumferential direction. The lugs 15A are inclined at a predetermined angle with respect to the circumferential direction of the tire body 11, and are formed at a constant interval (pitch) so that the intervals between the lugs 15A are equal. The lugs 15 </ b> A are made of rubber made of the same rubber material (composition) as the tire body 11 and have the same hardness as the tire body 11.

FIG.4 (b) is a perspective view which expands and shows the lug 15 of the tire 10 with a lug which concerns on a modification. This modification is different from the above embodiment in that two kinds of lugs 15 (lugs 15A and 15B) made of different rubber materials (compositions) are alternately arranged along the circumferential direction. More specifically, an outer peripheral surface 11A of the tire body 11 includes a lug 15A made of rubber that develops a predetermined hardness after vulcanization and a lug 15B made of rubber that develops a higher hardness than the lug 15A after vulcanization. It is formed so as to be staggered along the circumferential direction.
As shown in the present modification, the lug 15A and the lug 15B having higher hardness than the lug 15A are alternately formed, whereby the wear resistance of the lug-equipped tire 10 can be improved and desired friction can be achieved. The coefficient can be set.

FIG.4 (c) is a perspective view which expands and shows the lug 15 of the tire 10 with a lug which concerns on another modification. In the present modification, the lug 15B having a hardness higher than that of the lug 15A described above is formed laterally with respect to the circumferential direction in the vicinity of the center (center in the width direction) of the outer peripheral surface 11A of the tire main body 11. Different from the embodiment.
That is, a plurality of lugs 15A are formed in a state inclined at a predetermined angle along the outer peripheral surface 11A, as in FIG. The lugs 15A are formed from the vicinity of the center of the outer peripheral surface 11A to the shoulders (both ends in the width direction). On the other hand, the lug 15B having higher hardness than the lug 15A is formed in a state orthogonal (laterally) to the circumferential direction of the outer peripheral surface 11A, and is formed so as to alternate with the pair of lugs 15A; 15A. The The lug 15B is formed near the center of the outer peripheral surface 11A, and the tread surface 27 of the lug 15B is gradually inclined radially inward from the vicinity of the center to the shoulder side.
As shown in this modification, by forming the lug 15B having high hardness near the center of the lug-equipped tire 10, it is possible to further improve the wear resistance near the center where the wear is severe.

FIG.4 (d) is a perspective view which expands and shows the lug 15 of the tire 10 with a lug which concerns on another modification. This modification is different from the above embodiment in that the inclination angle of the lug 15A with respect to the circumferential direction of the outer peripheral surface 11A of the tire body 11 is changed. Specifically, the lug 15A is formed on the outer peripheral surface 11A in a state that is substantially orthogonal to the circumferential direction (substantially sideways). That is, the inclination angle of the lug 15A shown in FIG. 4D with respect to the circumferential direction is set to be smaller than the inclination angle of the lug 15A shown in FIG. 4A with respect to the circumferential direction.
As shown in the present modification, the traction performance of the lug-equipped tire 10 can be further increased by increasing the inclination angle of the lug 15A with respect to the circumferential direction.

As described above, the lug 15 of the lug-equipped tire 10 is formed by the lug 15A and the lug 15B made of rubber having higher hardness than the lug 15A, and the position of the lug 15 to be arranged is changed to the center side. By changing the inclination angle of the lug 15 with respect to the circumferential direction, the wear resistance can be improved and the traction performance can be increased, and the performance according to the usage environment and application of the lug-equipped tire 10 Can be exhibited.
The formation pattern of the lugs 15 and the inclination angle with respect to the circumferential direction are not limited to the above-described modification. For example, three or more types of lugs made of different rubber materials (compositions) can be used, and the inclination angles of the adjacent lugs 15 with respect to the circumferential direction can be individually set.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the said embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made to the above embodiment.

10 tires with lugs, 11 tire body, 11A outer peripheral surface,
15, 15A, 15B rug,
21, 21 ′ tire case, 21A, 21A ′ lug application surface, 25 lug member,
26 Non-tread, 27 Tread, 30 Cushion rubber, 31 Envelope,
40 Vulcanizer, 55 recess.

Claims (2)

A tire case having a lug application surface;
A plurality of lug members formed separately from the tire case and disposed on the lug application surface;
A tire with
The tire characterized in that the plurality of lug members include at least two types of lug members having different rubber properties. The tire according to claim 1, wherein a cushion rubber is interposed between the lug attaching surface and the lug member.

Images