THERMAL EXPANSION COMPENSATION SUPPORT

摘要

A thermal expansion compensation support (40) and method are used in a hot runner injection mold for maintaining liquid-tight relationships between parts that define a flow passageway. The support includes an annular housing (56) having an recess (64) that receives a spring (68), such as a Belleville washer, and a cover (70) that overlies the recess (64) in the housing (56). The housing (56) and the cover (70) are spring biased from each other to maintain a pressure force on the surfaces that are in contact with the outer faces of the cover (70) and housing (56). The support (40) imparts a holding force on the parts of the machine that define the molding material flow passageway to prevent leakage. The method involves holding the parts together at a first holding force level for an initial portion of a warm-up temperature range and holding the parts together at a second holding force level for the remainder of the temperature range.