Abstract: A seating apparatus for sealing a semiconductor element in a resin has a plunger which injects a resin pellet into the cavities of an upper and lower mold. The plunger is driven by a reciprocating mechanism through a flexible transmission member so that the directions of movement of the plunger and the reciprocating mechanism need not be parallel. In preferred embodiments, the reciprocating mechanism is a ball screw mechanism which is driven by a servomotor, and the flexible transmission member is a roller chain which is slidably disposed within a lower mold. The lower mold may be longitudinally divided into a plurality of sections which are detachably secured to one another to enable easy manufacture and disassembly. A ventilating mechanism for passing cooling air along the length of the roller chain during molding may be provided to prevent the roller chain from being damaged by the heat of molding.