Plasticizing device, injection molding machine, and three-dimensional shaping apparatus

A plasticizing device that plasticizes a solid material, the plasticizing device comprising:

• a drive motor;
• a screw rotated around a rotation axis by the drive motor and having a groove forming surface in which a groove is formed, the groove being configured with a bottom, a wall, and a rib;
• a barrel having a facing surface facing the groove forming surface and provided with a communication hole in a central portion thereof;
• and
• a heater configured to heat at least one of the screw and the barrel, wherein
• a first facing region and a second facing region are provided between the groove forming surface and the facing surface, and the second facing region is closer to the rotation axis than the first facing region,
• a first gap is formed between a first tip of the rib and the facing surface in the first facing region, and a second gap is formed between a second tip of the rib and the facing surface in the second facing region,
• the second gap is larger than the first gap,
• the second gap becomes large toward the rotation axis, and
• in a cross section along the rotation axis,
• at least one of the groove forming surface and the facing surface corresponding to the first facing region is inclined at a first angle with respect to an intersecting direction perpendicular to the rotation axis,
• at least one of the groove forming surface and the facing surface corresponding to the second facing region is inclined at a second angle with respect to the intersecting direction, and
• the first angle and the second angle are different.