| 摘要 |
PURPOSE:To obtain an in-mold pressure detecting equipment whose structure and fitting are simple, by a method wherein a highly sensible approach switch is provided on one side of a stationary platen and tie bar of an injection molding machine, and a material to be detected is provided on the other side of them by confronting with the highly sensible approach switch and separating from the switch by a given distance. CONSTITUTION:When the inside of molds 6, 7 are filled with molten resin in an injection process and the insides of the molds arrive at preset pressure, a tie bar 4 stretches. In consequence, a space between a stationary platen 2 and support member 50 is stretched by lock up and an injection action and a material 40 to be detected which in one with the tie bar 4 is moved in a separating direction to an optical 30 and a reflector face 41 of the material 40 to be detected is positioned at the maximum sensing point of the optical sensor 30. With this construction, irradiation rays thrown on the material 40 to be detected meet in a focus on the material 40 to be detected, a condensing degree becomes maximum and an electric output signal level from the optical sensor becomes either maximum or minimum according to constitution of the sensor. When the inside of the mold arrives at the preset pressure after output of the optical sensor 30 has been made into a binary signal, the same undergoes level inversion and arrival of the pressure to the preset pressure is detected. |
