Vacuum degasser, injection unit provided with same, and method for vacuum degassing

An injection unit, comprising:

• an injection cylinder;
• and
• a vacuum degasser that is attached to said injection cylinder,
• wherein said vacuum degasser comprises:
• conveyance equipment that conveys a molding material into said injection cylinder;
• a material supply path that is provided between said injection cylinder and said conveyance equipment and that supplies said molding material to said injection cylinder;
• a cutoff device that divides said material supply path into an upstream section that is connected to said conveyance equipment and a downstream section that is connected to said injection cylinder;
• a vacuum pump that is connected to said downstream section;
• and
• an atmospheric relief valve that is connected to said downstream section, wherein
• said atmospheric relief valve is opened in a state that precedes a measurement process and that said cutoff device and said atmospheric relief valve are closed and said vacuum pump is in operation.

A method for vacuum degassing using a vacuum degasser that comprises:

• conveyance equipment that conveys a molding material into an injection cylinder;
• a material supply path that is provided between said injection cylinder and said conveyance equipment and that supplies said molding material to said injection cylinder;
• a cutoff device that divides said material supply path into an upstream section that is connected to said conveyance equipment and a downstream section that is connected to said injection cylinder;
• a vacuum pump that is connected to said downstream section;
• and
• an atmospheric relief valve that is connected to said downstream section, the method comprising a step of:
• opening said atmospheric relief valve in a state that precedes a measurement process and that said cutoff device and said atmospheric relief valve are closed and said vacuum pump is in operation.