Method of producing waterproof connector housing having elongated slip-off preventing pieces

A method of manufacturing a waterproof connector housing having a hood portion used in engaging with a mating housing and a housing main body containing a terminal insertion portion, a stair portion connecting said hood portion to said terminal insertion portion and an elastic seal ring for maintaining water-tightness with said housing main body inside said hood portion, comprising the steps of:

• providing a mold containing cooperating mold portions formed to receive a pre-formed connector housing, wherein said stair portion is cooperable with one of said mold portions to position said housing within said mold,
• providing a substantially annular seal ring recess in one of said mold portions to cooperate with a part of said housing main body about an axis thereof to form a substantially annular seal ring cavity with said hood portion of said connector housing,
• forming a linking hole through said terminal insertion portion of said connector housing parallel to the axis thereof, said linking hole communicating at one end with said seal ring cavity and at its other end opening at a distal end of said terminal insertion portion of said connector housing,
• providing the other mold portion with an elastic material passage in axial alignment, and in communication with, said linking hole, and
• introducing a fluid elastic material to said passage for fluid flow through said linking hole to said seal ring cavity to fill said cavity and thereby integrally form said seal ring on said housing main body within said hood portion thereof.