| 摘要 |
<p>PURPOSE:To obtain a weather strip with a high accuracy without a limitation by the shape of a change part by a method wherein a shape of a product other than the change part is stabilized by adjusting a rubber extruding amount at the change part of the weather strip continuously changing in extrusion cross sectional shape in a longitudinal direction. CONSTITUTION:In the production of a weather strip continuously changing in extrusion cross sectional shape in a longitudinal direction, at the time of extruding a molded piece through product openings 1a, 1b, 1c of an extrusion head at the tip end of an extruder, a back pressure change caused by a change in weather strip cross sectional shape is kept constant as follows: a back pressure adjusting opening 2 is provided apart from the product openings; the shape and opening area of the back pressure adjusting opening 2 are determined to be the same as those of the change part 1c of the product openings; the opening 2 and the change part 1c are changed in conjunction with each other; and the opening areas are changed reversely to each other by the same amount.</p> |
