US 12,240,159 B2
Injection molding machine and method of controlling injection molding machine
Kenta Anegawa, Matsumoto (JP); and Kei Yokota, Matsumoto (JP)
Assigned to SEIKO EPSON CORPORATION, Tokyo (JP)
Filed by SEIKO EPSON CORPORATION, Tokyo (JP)
Filed on Dec. 22, 2020, as Appl. No. 17/130,888.
Claims priority of application No. JP2019-236188 (JP), filed on Dec. 26, 2019.
Prior Publication US 2021/0197434 A1, Jul. 1, 2021
Int. Cl. B29C 45/76 (2006.01); B29C 45/46 (2006.01); B29C 45/54 (2006.01); B29C 45/60 (2006.01); B29C 45/62 (2006.01); B29C 45/74 (2006.01); B29C 45/77 (2006.01); B29C 45/80 (2006.01)
CPC B29C 45/461 (2013.01) [B29C 45/54 (2013.01); B29C 45/60 (2013.01); B29C 45/62 (2013.01); B29C 45/74 (2013.01); B29C 45/77 (2013.01); B29C 45/80 (2013.01)] 13 Claims
OG exemplary drawing
 
1. An injection molding machine comprising:
a melting unit including a screw rotating about a rotation axis and having a groove forming surface on which a groove is formed and a barrel having a facing surface facing the groove forming surface and provided with a communication hole in the facing surface, and configured to plasticize a material supplied between the screw and the barrel to generate a plasticized material and make the plasticized material flow out of the communication hole, wherein
the screw includes a retention reducing portion that protrudes toward the communication hole, and
the retention reducing portion is at a central portion of the groove forming surface;
a curved projection strip is formed on the groove forming surface,
a portion of the curved projection strip extends, as a continuous structure, from a peripheral edge of the central portion to an outer periphery of the screw, wherein
the communication hole is at a position on the facing surface facing the central portion of the groove forming surface,
the retention reducing portion protrudes from the central portion toward the communication hole, and
the central portion of the groove forming surface providing a groove portion encircling the retention reducing portion to space a terminal end of the portion of the curved projection strip from the retention reducing portion;
a heating unit configured to heat the melting unit;
an injection nozzle in communication with the communication hole;
an injection control unit including a cylinder coupled to the communication hole and a plunger configured to move in the cylinder;
a pressure detection unit configured to detect a pressure of the plasticized material in the communication hole; and
a control unit, wherein
the control unit controls the injection control unit to execute, based on a value of the detected pressure, at least one of
a metering operation of metering the plasticized material in the communication hole in the cylinder by moving the plunger in a direction away from the communication hole, and
an injecting operation of injecting the plasticized material in the cylinder into a mold via the injection nozzle by moving the plunger in a direction approaching the communication hole.