Heavy duty pneumatic tire including variable width grooves...

Details Heavy duty pneumatic tire including variable width grooves... Heavy duty pneumatic tire including variable width grooves...

1998-06-25

2001-01-09

Maki, Steven D. (Department: 1733)

Resilient tires and wheels

Tires, resilient

Anti-skid devices

C152S209260, C152S209270, C152S902000, C152SDIG003

Reexamination Certificate

active

06170546

ABSTRACT:

The present invention relates to a pneumatic tire for heavy duty vehicles more particularly to an improvement in the tread portion capable of improving the resistance to abnormal tread wear.
In winter tires, snow tires, studless tires and the like which are used on snowy and icy roads, usually, a necessary road grip on the snow is mainly obtained by the use of tread blocks defined by relatively wide tread grooves, and that on the ice is mainly obtained by the use of a relatively soft tread rubber compound and the edges of the tread rubber formed by the wide tread grooves, narrow grooves and sipes. Accordingly, the blocks are inevitably decreased in the rigidity, and uneven wear is liable to occur between the blocks. As a result, it is difficult to maintain the required snow performance throughout the tread wear life. This is especially remarkable in the pneumatic tires for heavy duty vehicles such as trucks, buses and the like.
The inventors made a study of uneven wear of such tread blocks and found that uneven wear is liable to occur in the blocks divided by a wide circumferential groove and narrow circumferential groove and the wear progresses faster on the wide circumferential groove side of the blocks than the narrow circumferential groove side.
It is therefore, an object of the present invention to provide a heavy duty pneumatic tire in which blocks divided by wide circumferential grooves and narrow circumferential grooves are prevented from abnormal wear and the snow performance can be maintained throughout the tread wear life.
According to the present invention, a heavy duty pneumatic tire is provided in the tread portion with wide circumferential grooves having a width Wml of 4.0 mm to 20.0 mm, narrow circumferential grooves having a width Wm
2
of not less than 2.0 mm but less than 4.0 mm, and axial grooves each extending from one of the wide circumferential grooves to the adjacent narrow circumferential groove to form blocks, the axial grooves having a variable-width increasing from the wide circumferential groove to the narrow circumferential groove.
Therefore, the blocks are increased in the rigidity on the wide groove side rather than the narrow groove side, and as a result, the movements of the blocks are evened to decrease abnormal wear.


REFERENCES:
patent: 5137068 (1992-08-01), Loidl et al.
patent: 5327953 (1994-07-01), Ichiki
patent: 5526860 (1996-06-01), Minami
patent: 5538060 (1996-07-01), Van Der Meer et al.
patent: 6003575 (1999-12-01), Koyama et al.
patent: 3424796 (1985-01-01), None
patent: 393012 A2 (1990-10-01), None
patent: 469816 A2 (1992-02-01), None
patent: 513676 A1 (1992-11-01), None
patent: 718125 A1 (1996-06-01), None
patent: 729854 A2 (1996-09-01), None
patent: 63-275406 (1988-11-01), None
patent: 1-254406 (1989-10-01), None
patent: 3-157207 (1991-07-01), None
patent: 4-133805 (1992-05-01), None
patent: 5-254311 (1993-10-01), None
patent: 6-115322 (1994-04-01), None
Japanese Patent Abstract 06171311, vol. 018, No. 503 (M-1677), Sep. 21, 1994.
Japanese Patent Abstract 61226304, vol. 011, No. 071 (M-567), Oct. 8, 1986.
Japanese Patent Abstract 06115320, vol. 018, No. 398 (M-1645), Jul. 26, 1994.

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