Injection molding machine and injection molding machine screw for injecting molten resin in which thermoplastic resin and reinforcing fibers have been mixed and melted

An injection molding machine comprising:

• a screw rotatably provided in a heating cylinder, the injection molding machine being configured to inject a molten resin, in which a thermoplastic resin and reinforcing fibers are mixed and melted, into a cavity of a clamped mold from an injection nozzle attached to a tip of the heating cylinder, wherein
• the screw includes
• a compression section configured to melt, mix and compress a material while conveying the material forward, and
• a mixing section configured to stir, mix, and disperse a molten material conveyed from the compression section, the molten material consisting of the thermoplastic resin and the reinforcing fibers,
• the compression section and the mixing section located downstream of the compression section each are configured of a helical flight,
• the helical flight of the compression section is formed of one continuous helical screw flight having a gradually-decreasing pitch along a material conveyance direction, and
• the helical flight of the mixing section includes a plurality of grooves formed in a surface of the helical flight, the helical flight being not a continuous helical flight.