Injection molding device and mold opening and closing device

An injection molding device that uses a mold configured by a fixed mold and a movable mold to perform injection molding of a molded article, the injection molding device comprising:

• an injection unit configured to inject a material of the molded article into the mold;
• a mold opening and closing unit to which the mold is attached and which opens and closes the mold;
• and
• a control section configured to control the injection unit and the mold opening and closing unit, wherein
• the mold opening and closing unit includes
• a toggle fixing section,
• a fixed mold attachment section to which the fixed mold is attached,
• a movable mold attachment section that is provided between the toggle fixing section and the fixed mold attachment section so as to be movable forward and backward in a mold opening and closing direction and that has the movable mold attached thereto,
• a crosshead configured to move between the toggle fixing section and the movable mold attachment section, and
• a toggle section that is connected to the toggle fixing section, the movable mold attachment section, and the crosshead, and that is configured to move the movable mold attachment section along the mold opening and closing direction by movement of the crosshead,
• the toggle section includes
• a plurality of pivot sections including a first pivot section, a second pivot section, a third pivot section, a fourth pivot section, and a fifth pivot section,
• a first member that is coupled to the toggle fixing section via the first pivot section,
• a second member that is coupled to the first member via the second pivot section and that is coupled to the movable mold attachment section via the third pivot section, and
• a third member that is coupled to the first member via the fourth pivot section and that is coupled to the crosshead via the fifth pivot section,
• each of the pivot sections has a pivot shaft,
• the first member, the second member, and the third member each have an insertion hole through which the pivot shaft is inserted,
• at least one of the plurality of pivot sections includes
• a bearing provided between the pivot shaft and the insertion hole, and
• a plurality of protection members that are provided between the pivot shaft and the insertion hole, that are arranged with the bearing in an extending direction of the pivot shaft, and that include a first protection member and a second protection member,
• the bearing is located between the first protection member and the second protection member, and
• a first lubricant holding section that holds lubricant is provided at least one of between the bearing and the first protection member and between the bearing and the second protection member.