US 12,434,419 B2
Abnormality detection device for extrusion molding machine
Masatoshi Ohara, Numazu (JP); Kentaro Taki, Kanazawa (JP); and Tsukasa Kida, Kanazawa (JP)
Assigned to Shibaura Machine Co., Ltd., Chiyoda-ku (JP); and NATIONAL UNIVERSITY CORPORATION KANAZAWA UNIVERSITY, Kanazawa (JP)
Appl. No. 17/618,946
Filed by Shibaura Machine Co., Ltd., Chiyoda-ku (JP); and NATIONAL UNIVERSITY CORPORATION KANAZAWA UNIVERSITY, Kanazawa (JP)
PCT Filed May 25, 2020, PCT No. PCT/JP2020/020591
§ 371(c)(1), (2) Date Dec. 14, 2021,
PCT Pub. No. WO2021/002119, PCT Pub. Date Jan. 7, 2021.
Claims priority of application No. 2019-123414 (JP), filed on Jul. 2, 2019.
Prior Publication US 2022/0242031 A1, Aug. 4, 2022
Int. Cl. B29C 48/92 (2019.01); G01M 99/00 (2011.01); B29C 48/40 (2019.01)
CPC B29C 48/92 (2019.02) [G01M 99/005 (2013.01); B29C 48/40 (2019.02); B29C 2948/92295 (2019.02); B29C 2948/92361 (2019.02)] 4 Claims
OG exemplary drawing
 
1. An abnormality detection device for an extrusion molding machine, comprising:
an acquisition unit that acquires an elastic wave emitted inside the extrusion molding machine according to the operating state of the extrusion molding machine by an acoustic emission (AE) sensor, installed on a surface of a housing of the extrusion molding machine that melts and kneads a fed resin raw material when the extrusion molding machine is in operation;
a determination unit that determines whether an abnormality occurs in the extrusion molding machine, based on a relationship between the output of the AE sensor acquired by the acquisition unit and a threshold value related to the output magnitude of the AE sensor; and
a control unit that controls an operating status of the extrusion molding machine based on a judgement of the determination unit, wherein
the threshold includes a first threshold and a second threshold that is larger than the first threshold,
when the determination unit determines that crushing of an unmelted resin raw material occurs in a case where the output of the AE sensor acquired by the acquisition unit exceeds the first threshold and does not exceed the second threshold, the control unit increases a set temperature of a heater to promote melting of the resin raw material, and
when the determination unit determines that wear of a screw that conveys the resin raw material from upstream to downstream, a barrel, or a kneading disk that kneads the resin raw material occurs in a case where the output of the AE sensor acquired by the acquisition unit exceeds the second threshold, the control unit reduces an amount of the resin to be fed or increases the set temperature of the heater to promote melting of the resin raw material.