Apparatus and method for providing a seal around a perimeter of a bi-material enclosure

摘要

An enclosure includes a seal 108 co-molded to a first material 102 to form a sub­assembly in which the first material is securely adhered to the seal. The seal is designed to collapse in a specific direction during an injection molding process. The enclosure also includes a second material 104 over-molded on the sub­assembly during the injection molding process. The seal is compressed in the specific direction during the injection molding process to produce a consistent wetting at least at one desired perimeter joint between the seal and the over-molded second material, forming the bi-material enclosure. The first material and the second material are dissimilar materials with different thermal expansion qualities. A groove may be etched with a micro pattern onto a prefabrication of the first material to enhance adhesion of the seam to the first material. The invention is particularly useful for fabricating a housing for a mobile device wherein a thin metal sheet may be over-moulded by a thicker plastic enclosure. The seal prevents any leakage paths and the deflection of the seal allows for relaxation of the seal during temperature shock cycles.