Comprehensive areal geometric quality characterisation of injection moulded thermoplastic gears

Urbas, Uroš (author), Zorko, Damijan (author), Vukašinović, Nikola (author), Černe, Borut (author)

Injection moulding is currently the most widely employed production method for polymer gears. Current standardised gear metrology methods, which are based on metal gear inspection procedures, do not provide the key information regarding the geometric stability of injection moulded gears and are insufficient for a thorough gear inspection. The study developed novel areal quality parameters, along with a so-called moulding runout quality parameter, with a focus on the injection moulding method. The developed parameters were validated on twenty-nine gear samples, produced in the same moulding tool using various processing parameters. The gears were measured using a high-precision structured-light 3D scanner. The influence of injection moulding process parameters on the introduced novel quality parameters was investigated. The developed moulding runout quality parameter proved to be effective in evaluating the shrinkage that can occur in the injection moulding process. The novel moulding runout parameter returned an average value of −21.8 μm in comparison to 29.4 μm exhibited by the standard parameter on all the gears, where the negative value points directly to mould shrinkages. The rate of cooling was determined to be the most influential factor for the shrinkage of the gear. The developed areal parameters demonstrated to be advantageous in characterising the deviations on the teeth more comprehensively.

• Language: English
• Keywords: gear metrology, injection moulding, geometrical quality parameters, polymer gears
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2022
• Number of pages: 19 str.
• Numbering: Vol. 14, iss. 4, art. 705
• PID: 20.500.12556/RUL-135121
• UDC: 621.83.052:678.027.74
• ISSN on article: 2073-4360
• DOI: 10.3390/polym14040705
• COBISS.SI-ID: 97321219
• Publication date in RUL: 23.02.2022

Record is a part of a journal

• Title: Polymers
• Shortened title: Polymers
• Publisher: MDPI
• ISSN: 2073-4360
• COBISS.SI-ID: 517951257

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 12.02.2022

Secondary language

• Language: Slovenian
• Keywords: zobniško meroslovje, injekcijsko brizganje, parametri geometrijske natančnosti, polimerni zobniki