PURPOSE: To simplify the structure of molds so as to make multiple moldings possible simultaneously by a method wherein the slide core of the molds and the undercutting after ejection are eliminated by changing some part of the shape of a guard panel covering the opening part of a cassette case.
CONSTITUTION: The guard panel concerned has a plate body, which consists of a front plate 41 having no projection at its tip 31 and an upper surface plate 42 and a nearly L-like section, and side face plates 40, on the inside of each of which an upright pivot shaft 34 is equipped. Further, a plurality of projected parts running to the direction of the tip 31 may well be provided on the underside of the front plate 41. A mold is mode of a long and narrow cavity 38 having a L-shaped section for forming the front plate 41 and the upper surface plate 42 of the panel and cavities 39 for the side face plates, each of which is connected either one of both the ends of the cavity 38 for forming the side face plate. In addition, semicircular cylindrical cavities are provided on the molds 32 and 33 so as to form circular cylindrical cavities 36, when the molds 32 and 33 are joined together in order to respectively form the pivot shaft 34 inside each side face plate 40.
ISHIKAWA YUJI
KOYAMA ATSUSHI
