Sumitomo Rubber Industries Limited

Ryuhei Sanae

Masatoshi Tanaka

Shotaro Abe

Sho Nakajima

Yoshiaki Kanematsu

Shintaro Tomita

Daisuke Kudo

Renya Okawara

Sawa Ogihara

Rena Onitsuka

Yuto Hashimoto

Yosuke Komori

Tatsuya Sasaki

Nozomi Bamba

Ken Miyazawa

Shiho Okabayashi

Kosuke Miyoshi

Takayuki Namera

Shogo Izakura

Ryo Miura

Kentaro Oka

Emi Ueda

Naoto Oishi

A tire has a tread portion including a first shoulder land region. The first shoulder land region is provided with first shoulder sipes. Each of the first shoulder sipes is provided with a chamfered portion over an entire lengthwise range from a first longitudinal edge to a first tread edge. Each of the chamfered portions includes a first chamfered portion defined between a shoulder center position and the first longitudinal edge and a second chamfered portion defined between the shoulder center position and the first tread edge. The second chamfered portion has a chamfer volume smaller than a chamfer volume of the first chamfered portion.

Tire

A tire has a tread portion including a first shoulder land region. The first shoulder land region is provided with first shoulder sipes. Each of the first shoulder sipes is provided with a chamfered portion over an entire lengthwise range from a first longitudinal edge to a first tread edge. Each of the chamfered portions includes a first chamfered portion defined between a shoulder center position and the first longitudinal edge and a second chamfered portion defined between the shoulder center position and the first tread edge. The second chamfered portion has a chamfer volume larger than a chamfer volume of the first chamfered portion.

A mold includes a tread-forming surface to shape a tread surface. The tread-forming surface can include projections to form circumferential grooves, and land surface-forming portions to form land surfaces. Among the three land surface-forming portions aligned in an axial direction with the projections interposed therebetween, the land surface-forming portion located between the two projections can be a curved land surface-forming portion. A contour of the curved land surface-forming portion can be represented by one or more circular arcs. A boundary between a reference side surface of each projection and the curved land surface-forming portion can be a reference boundary point, and the reference boundary point can be located inward of a reference forming surface of the tread-forming surface.

Tire mold and production method for tire using a tire mold

A rim guard of a tire has a top, an inner surface, and an outer surface. A contour of the inner surface is represented by a circular arc, and the circular arc has a radius of not less than 20 mm and not greater than 30 mm. A contour of the outer surface is represented by a circular arc, and the circular arc has a radius of not less than 100 mm and not greater than 500 mm. In a radial direction, a position of an outer edge of the outer surface coincides with a cross-sectional width specified position, or the outer edge of the outer surface is located outward of the cross-sectional width specified position.

Pneumatic tire, mold for tire, and method for manufacturing tire

A tyre mold for curing and molding a tyre includes a plurality of tread segments for molding a tread rubber of the tyre. The plurality of tread segments, upon being connected with one another in a mold circumferential direction, forms a tread molding-surface that is substantially continuous in the mold circumferential direction through parting lines that appear between adjacent tread segments. The parting lines include one or more inclined parting lines inclined with respect to a mold axial direction, and the inclined parting lines extend straightly between ends in the mold axial direction of the tread molding-surface.

Tyre mold, method for manufacturing tyre, and tyre

A pneumatic tire comprises a tread portionhaving an outside tread edge Teo and an inside tread edge Tei to be positioned outside and inside, respectively, with respect to a vehicle. The tread portionis axially divided into land regionsby four main groovesincluding an outside shoulder main groove, an inside shoulder main grooveand two crown main grooves. The outside shoulder main groovehas a width smaller than the inside shoulder main grooveand the crown main grooves. The land portionsinclude an inside shoulder land regionprovided with inside shoulder lateral grooves. Each of the land regionsis provided with sipeseach extending across the entire width of the land region and having a width less than 3 mm.

Pneumatic tire

A pneumatic tire includes a tread portion provided with main grooves extending continuously in the tire circumferential direction, the main grooves include an outboard shoulder main groove and an outboard crown main groove between which an outboard middle land region is defined. The outboard middle land region is provided with outboard middle transverse grooves having a shallow groove section and a deep groove section. The outboard middle transverse grooves include first and second outboard middle transverse grooves that are arranged alternately in the tire circumferential direction.

A pneumatic tire is provided in a tread portionwith shoulder main groovesandand a center main grooveand divided into shoulder land portionsandand crown land portionsand. The total width of the shoulder main groovesandand the center main grooveis 24% to 28% of the tread width TW. The crown land portionsandare not provided with a groove having a width of not less than 2 mm and extending across the entire width of the crown land portion, but provided with a plurality of crown sipeshaving a width of less than 2 mm. The crown sipesinclude first sipescomprising a lateral direction partextending parallel with the tire axial direction and an oblique partinclined with respect to the lateral direction part. The ratio &#x3a3;Ly/&#x3a3;Ls of the sum &#x3a3;Ly of the lengths Ly of the lateral direction partsand the sum &#x3a3;Ls of the lengths Ls of the crown sipesis not more than 0.15.

Tire for automobile

A pneumatic tire has: a circumferential groove on each side of the tire equator; oblique grooves extending from the circumferential groove while inclining to one circumferential direction; and lug grooves extending axially outwardly beyond the tread edges from positions axially outside the circumferential groove while inclining to the one circumferential direction. The lug grooves include: a first lug groove comprising an axially inner steeply-inclined part and an axially outer mildly-inclined part; and a second lug groove extending along the mildly-inclined part. The axially inner end of the first lug groove is at a distance La of 8 to 12% of the tread width from the circumferential groove. The steeply-inclined part inclines at an angle larger than an inclination angle of the oblique grooves.

Growing community of inventors

Kobe, Japan

Ryuhei Sanae