Patent ID: 6220844
Filing Date: 2001-04-24
Classification: B29D,B60C

Abstract:
A vulcanization mold for producing a tire having a tread pattern formed by defining land portions by at least one circumferential groove extending along a circumference of a tread and both tread ends and arranging many lug grooves extending in a direction across the circumferential groove in each of the land portions in a circumferential direction of the tread, wherein the mold is segmented by partition lines each extending in parallel to a widthwise direction of the mold at a position excluding a protrusion for the formation of the lug groove in the tread pattern and constructed by arranging and combining many segments, each of which segments being defined between the adjacent partition lines and having a similar telescopic shape of n different types in the circumferential direction, wherein n is an integer of 2 to 4; and the number of types of pitches each defined as a distance between the protrusions of the adjacent combined segments is at least n+1 on the same circumference line; and a difference of pitch between different combinations of adjacent segments of different similar telescopic shapes is always not less than 0.5 when the pitch between protrusions of the combined segments is represented by an index of a pitch ratio on the basis that a maximum value of the pitch is 10.