A ground contact region of the tread portion of a studdable tire includes a center region located over a range corresponding to a length of 5 to 25% of a ground contact width from a tire centerline on each of both sides of the tire centerline in a tire width direction; and two shoulder regions located on both sides of the center region in the tire width direction. In each of the center region and the shoulder regions, a plurality of the stud pin installation holes are disposed along each of four or more pin arrangement lines extending in a tire circumferential direction. An average value of adjacent intervals between the pin arrangement lines in the center region is larger than an average value of adjacent intervals between the pin arrangement lines in each of the shoulder regions.

A method for making a blind hole in a prefabricated tire and a method for inserting an insert to such a blind hole are disclosed. The former comprises arranging available a prefabricated tire comprising tread blocks forming the tread of the tire, and thereafter machining such a blind hole to a tread block of the tire that the blind hole has a first cross section at a first depth and a second cross section at a second depth, wherein the second cross section is greater than the first cross section and the second depth is greater than the first depth.

A tire mold comprises sector molds for forming a tread portion of a tire and mold pins provided on the sector molds for forming insertion holes in the tread portion. The insertion holes each comprise a first hole portion with a first inner diameter where a body portion of a stud pin is disposed and a second hole portion with a second inner diameter greater than the first inner diameter where a bottom flange portion of the stud pin is disposed. The mold pins each comprise a trunk portion with a first outer diameter for forming the first hole portion and a tip portion with a second outer diameter greater than the first outer diameter for forming the second hole portion.

A method for installing a stud in a tyre. The method includes identifying a stud hole for the stud in the tyre; imaging the vicinity of at least the stud hole, whereby information is received about the pattern in the vicinity of the stud hole, and using the received information to determine [i] the stud type suitable for the stud suitable in the stud hole and/or [ii] the suitable stud orientation of the stud suitable in the stud hole. The method includes providing a stud and installing it in a stud hole. The stud type of the stud is the same as the suitable stud type of a stud suitable in the stud hole; and/or the stud is installed in the stud hole in such a way that the main direction of the stud is parallel with the suitable stud orientation. Further a tyre studded by the method.

A tyre comprises a tread portion comprising a first tread edge and a second tread edge, and the tread portion is provided with a plurality of oblique grooves. The plurality of the oblique grooves includes a first oblique groove and a second oblique groove. Each of the first oblique grooves and the second oblique grooves has an open end and a terminating end, and a first steeply-inclined portion positioned on a side of the open end, a second steeply-inclined portion positioned on a side of the terminating end, and a mildly-inclined portion positioned between them. The second steeply-inclined portion includes a part in which an angle thereof with respect to a tyre circumferential direction is gradually decreased as it goes toward the terminating end.

This invention relates to a tire having a directional tread pattern with a first shoulder region, a central region, and a second shoulder region, the tire having a plurality of studs in the first shoulder region, the second shoulder region, and the central region; wherein at least some of the plurality of the studs in the central shoulder region extends longitudinally into the tread member in a direction inclined relative to the normal of the outer surface of the tread member by an angle in the circumferential direction of the tire, and wherein at least some of the studs in the first shoulder region and the second shoulder region extend longitudinally into the tread in a direction inclined relative to the normal of the outer surface of the tread in a direction different from the studs in the central region.

A stud pin includes a tip including an end surface that comes into contact with a road surface, a body portion that supports the tip; and a lower flange connected to the body portion at an end on an opposite side to the end surface. A profile shape of the lower flange is an anisotropic shape in which, of imaginary rectangles circumscribing the profile shape, a first smallest rectangle with the shortest side of its four sides being the shortest and/or a second smallest rectangle with the longest side of its four sides being the shortest includes short sides and long sides of different lengths. The profile shape includes four or more first protrusion portions that project in the longitudinal direction parallel with the long sides and two second protrusion portions that project in the lateral direction parallel with the short sides.

In a pneumatic tire, a tread portion is provided with center blocks and shoulder blocks, and sidewall portions are each provided with side blocks. Surfaces of the blocks are provided with groove elements each including a narrow groove and/or a sipe. The first groove elements provided in the side blocks, the second groove elements provided in the shoulder blocks, and the third groove elements provided in the center blocks form a set of lateral groove group extending continuously from the side block on a first side to the side block on a second side in the tire lateral direction along the blocks across a main groove or an auxiliary groove.

In a pneumatic tire, a tread portion is provided with center blocks and shoulder blocks, and sidewall portions are each provided with side blocks. Surfaces of the blocks are provided with groove elements each including a narrow groove and/or a sipe. The first groove elements provided in the side blocks, the second groove elements provided in the shoulder blocks, and the third groove elements provided in the center blocks form a set of lateral groove group extending continuously from the side block on a first side to the side block on a second side in the tire lateral direction along the blocks across a main groove or an auxiliary groove.

A pneumatic tire includes a plurality of blocks formed by being divided by a longitudinal groove in a tire width direction and divided by a lateral groove in a tire circumferential direction. The blocks include a first block on the inner side in the tire width direction, a second block on the outer side in the tire width direction, a third block adjacent to the first block in the tire circumferential direction, and a fourth block adjacent to the second block in the tire circumferential direction. The pneumatic tire includes a bridge formed in the longitudinal groove and the lateral groove and coupling the first block, the second block, and the third block, or the third block, the fourth block, and the second block.