**5. Patents**

Monieta, J. The method and device for measuring the maximum friction force between the body and the needle of the injector in piston internal combustion engines Patent description PL 234940 B1, Patent Office of the Republic of Poland, Warsaw 2020, pp. 1–18. https://api-ewyszukiwarka.pue.uprp.gov.pl/api/collection/c2acbe35211e85ad2 7141555bd72d00d (accessed on 1 May 2020).

**Author Contributions:** Conceptualization, L.K. and J.M.; methodology, J.M.; software, L.K. and J.M.; validation, J.M.; formal analysis, L.K. and J.M.; investigation, J.M.; resources, J.M.; data curation, J.M.; writing—original draft preparation, L.K. and J.M.; writing—review and editing, L.K. and J.M.; visualization, L.K. and J.M.; supervision, J.M.; funding acquisition, L.K. and J.M. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research outcome has been achieved under the research project "Ecological and economic aspects of the operation of selected elements of marine energy systems" No. 1/S/IESO/2014 and No. 1/S/IMFiCH/21 financed from a subsidy of the Ministry of Science and Higher Education for statutory activities.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.
