Design and Application of Non-Circular Gear with Cusp Pitch Curve
Round 1
Reviewer 1 Report
I am very glad that there are still works on gears with non-round wheels.
It turns out that at one time new, interesting and practical applications were found for these solutions.
1. Title of work well its content.
2. In the abstract, the authors give an opportunity to outline the availability of the publication. Mine is in place.
3. We service the authors clearly set the goals and scope of work in the literature review, the authors prove themselves on the work carried out in China. I suggest that you consider extending the literature with inserted items:
Krawiec, P.; Grzelka, M.; Kroczak, J.; Domek, G.; Kołodziej, A. A proposal of measurement methodology and assessment of manufacturing methods of nontypical cog belt pulleys. Measurement 132 2019 182–190 https://doi.org/10.1016/j.measurement.2018.09.039
Krawiec, P.; Domek, G.; Warguła, Ł.; Waluś, K. The application of the optical system ATOS II for rapid prototyping methods of non-classical models of cogbelt pulleys. In MATEC Web of Conferences https://doi.org/10.1051/matecconf/201815701010., Sklené Teplice, Slovak Republic, 5–8 September 2017. pp.157 2018 01010-1-7. https://doi.org/10.1051/matecconf/201815701010
Medvecká-Beňová, S. Designing pitch curves of non-circular gears. Scientific Journal of Silesian University of Technology. Series Transport. 2018 99 105-114. https://doi.org/10.20858/sjsutst.2018.99.10.
Maláková, S.; Urbanský, M.; Fedorko, G.; Molnár, V.; Sivak, S. Design of Geometrical Parameters and Kinematical Characteristics of a Non-circular Gear Transmission for Given Parameters. Appl. Sci. 2021, 11, 1000. https://doi.org/10.3390/ app11031000
Cristescu, A.; Cristescu, B.; Andrei, L. Finite element analysis of multispeed noncircular gears. Appl. Mech. Mater. 2015, 808, 246–251.
Niculescu, M.; Andrei, L. Using noncircular gears for the unloading door kinematics modification. In: Proceedings of the MATEC Web of Conferences, vol. 112, 6013. Iasi, Romania (2017). 0.1051/matecconf/201711206013
Nezir, E.; Nihat, Y.; Fatih, E., Bahadır, K., Burak, Ş.
Non-circular gear design, elliptical gears as example
(2019) Ejons VI – International Conference on Mathematics – Engineering – Natural & Medical Sciences, pp. 624-641. Adana, Turkey
4. In the second chapter, entitled Design principle of VIIVC-CTF, they presented the relationships that they used to determine the geometry of the teeth. In my opinion, they are sufficient. In addition, they provided a block diagram of software development for the design of non-circular gears with a subdivision curve. The proposed software supporting the selection of geometric features of non-circular wheels deserves recognition. Unfortunately, figure 5 is not legible and its quality should be improved.
In Chapter 3, Figure 6 deserves attention. This chapter shows that the addition of the bc tooth profile decreases as the turning radius increases, but a very small turning radius leads to the intersection of the tooth profiles, making it impossible to completely design the pitch curve (i.e. correct transmission the requirements of a non-circular jump curve cannot be met). Likewise, the tooth profile ad diminishes as the turning radius increases. The very small turning radius also leads to the profile intersection.
In my opinion, details I and II should be enlarged. This will facilitate the analysis of the issue.
Chapter 4 shows that the radius of curvature with a variable cycloidal tooth profile shows an increase along the direction of the tooth profile, especially at the starting point of the tooth pitch.
The curve of the radius of curvature of the tooth profile with a cycloid variable at different angles
the elliptical eccentricity (the turning radius is an ellipse) shows that when the elliptical eccentricity is 0, it is a standard circle. As the elliptical rolling eccentric increases, the radius of curvature of the cycloidal tooth profile is usually larger.
The fifth chapter is devoted to the use of Adams software to conduct a virtual simulation of the gear mechanism and the angular displacement curve. Figure 15 compares the theoretical angular displacement and transmission curve with the simulation made in the Adams software results.
In Chapter 6, I suggest other possible methods of machining non-circular circles.
The driving and driven non-circular gears are produced by the wire cutting method. What accuracy of wheel contours and surface roughness were obtained?
The achievements of this work are as follows:
a method of designing non-circular gears has been proposed,
a construction platform for a non-circular gear with a curve was developed.
The gear driving the non-circular curved gearbox is designed using the new VIIVC-CTF
the driven gear with non-circular wheels is designed on the basis of the envelope method.
the relationship between the variability and the curvature of the tooth profile is sufficiently shown.
The mathematical model of the driving gear tooth profile and the non-circular driven gear model are constructed using the normal method and the envelope method.
Virtual tests of the non-circular gear mechanism were carried out. By comparing the theoretical and virtual values of the transmission curve, the transmission capacity of the transmission is assessed.
By comparing the trajectory of the seedling picking by the seedling picking mechanism, theoretical, simulation and experimental are consistent, which has been verified in practice.
Please indicate why the use of non-round wheels will be better suited to the task than other control methods.
After the necessary additions and corrections, I recommend publishing the work.
Author Response
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Author Response.pdf
Reviewer 2 Report
The authors of the paper propose a new variable-involute and incomplete variable-cycloid composite tooth profile , deduced the new mathematical model and constructed the conjugate gear model based on the envelope method.
The work is interesting and brings important contributions in the field of non-circular gears. In addition to the theoretical proposal, it is also verified in practice. The work is well organized. The documentation part is sufficient and the contributions are clearly presented.
I believe that the work can be published after small corrections related to the clarity of figures 5-15.
Thanks
Author Response
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Reviewer 3 Report
The paper deals with design of non-circular gear with cusp pitch curve. New variable-involute and incomplete variable-cycloid composite tooth profile is described. The authors have developed software for creation non-circular gear with cusp pitch curve in MATLAB. The application was verified by seedling picking experiment with the seedling pick-up mechanism. The article may be of interest to professionals working in the field of gear design. Errors in the article are marked in the attached file.
Comments for author File: Comments.pdf
Author Response
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Reviewer 4 Report
Paper is interesting and it is dealing with design problem of non-circular gear with cusp pitch curve. Authors find a way to solve problem of transition from circular to non-circular toothing.
Figure 5 is unclear. Please improve quality.
It is not clear which Figure is 12 and 13.
On the end on 1. Introduction you should add that you are going to show application of non-circular gear with cusp pitch curve. Also, it would be advisable to add few sentence about possible applications. On the end of paragraph is missing ".".
In "6. Application ..." before 6.1 authors should explan what are key advantages of non-circular gears with cusp pitch curve.
"Figure 18" should be mention in text before the Figure is shown. It should be checked in all cases.
Author Response
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Round 2
Reviewer 1 Report
All my comments have been implemented.
The work can be published in this form.
Congratulations on your interesting article.
