• International Journal of Precision Engineering and Manufacturing
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• v.2 no.2
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• pp.57-64
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• 2001

In recent years, the concern of designing multi-stage gear drives ha increased with more application of them in high-speed and high-load. Until now, however, the researches on the design of gear drives have been focused on single gear pairs. Thus the design practice for multi-stage gear drives has been depended on experiences and expertise of designers and carried out commonly by trial and error. We propose an automation algorithm for the design of two-and three-strage cylindrical gear drives. The two types of dimensional design processes have been proposed to determine gear dimensions in a formal way. The first design process(Process I) uses to total volume of gears to determine gear ration , and uses K factor , unit load and aspect ration to determine gear dimensions, The second one(Process II) makes use of Niemann's formula and center distance to calculate gear ratio and gear dimensions. Process I and Process II employ material date from AGMA and ISO standards, respectively. The configuration design determines the positions of gears with minimizing the volume of gearbox by using a simulated annealing algorithm. The availability of the design algorithm is validated by the design examples to two-and three=stage gear drives.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.9
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• pp.202-209
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• 2000

In recent years the concern of designing multi-stage gear drives increases with the more application of gear drives in high-speed and high-load. until now however research on the gear drive design has been focused on single gear pairs and the design has been depended on experiences and know-how of designers and carried out commonly by trial and error. We propose the automation of the dimensional design of gears and the configuration design for gear arrangement of two-and three-stage cylindrical gear drives. The dimensional design is divided into two types of design processes to determine the dimensions of gears. The first design process(Process I) uses the total volume of gears to determine gear ratio and uses K factor unit load and aspect ratio to determine gear dimensions. The second one(Process II) makes use of Niemann's formula and center distance to calculate gear ratio and dimensions. Process I and II employ material data from AGMA and ISO standards respectively. The configuration design determines the positions of gears to minimize the volume of gearbox by simulated annealing algorithm. Finally the availability of the design algorithm is validated by the design examples of two-and three-stage gear drives.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.464-469
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• 1999

Recently, the need for designing multi-stage gear drive has been increased as the hear drives are used more in the applications with high-speed and small volume. The design of multi-stage gear drives includes not only dimensional design but also configuration design of various machine elements. Until now, however, the researches on the design of gear drives are mainly focused on the single-stage gear drives and the design practices for multi-stage gear drives, especially in configuration design activity, mainly depend on the experiences and 'sense' of the designer by trial and error. We propose a design algorithm to automate the dimension design and the configuration design of multi-stage gear drives. The design process consists of four steps. The number of stage should be determined in the first step. In second step, the gear ratios of each reduction stage are determined using random search, and the ratios are basic input for the dimension design of gears, which is performed by the exhaustive search in third step. The designs of gears are guaranteed by the pitting resistance and bending strength rating practices by AGMA rating formulas. In configuration design, the positions of gears are determined to minimize the volume of gearbox using simulated annealing algorithm. The effectiveness of the algorithm is assured by the design example of a 4-stage gear drive.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.398-403
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• 2000

The design of multi-stage gear drives is a time-consuming process that includes additional design problems, which are not considered in the design of single-stage gear drives. In the previous research works, the authors have proposed a new algorithm to design multi-stage gear drives at the preliminary design phase. The proposed design algorithm automates the design process by integrating the dimensional design and the configuration design process. In the configuration design process, the positions of gears and shafts are determined by minimizing the geometrical volume (size) of a gearbox. However, various types of spatial constraints should be satisfied in practical design situation. To locate input and output shaft in specified positions is the typical example of such problems. In this paper, the authors show the formulations of spatial constraints applied to the design of four-stage gear drives. The design solution shows considerably good results, and the design system is confirmed to be readily applicable to practical design situation.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.4
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• pp.79-86
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• 2004

Tooth errors inevitable in the manufacturing process have large effect on the strength/durability and vibration performances of gear drives. We show that the manufacturing errors affect the overall gear performances, especially vibration performance, and propose a robust optimal design method for gear dimension and its tooth flank form that guarantees reliable performances to the variation of manufacturing errors. This method begins with a search of optimal design candidates by using the previously developed gear optimal design method for the strength/durability and vibration performances. Then, the statistical analysis method is applied to find a robust design solution for the vibration performance which is generally very sensitive to the manufacturing variations.

• Tribology and Lubricants
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• v.39 no.5
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• pp.173-182
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• 2023

The composite planetary gear reducer, a power transmission component of armored vehicles, operates at a high torque and is used in severe environments such as mountain, gravel or unpaved roads. Therefore, they must be designed and manufactured to have high durability. To design such a planetary gear reducer, there are numerous specifications to validate, such as selecting the module and the number of teeth of each gear satisfied the requirements, and calculating gear specifications and durability strength. Because planetary gears constitute a combination of several gears, there are many restrictions and interferences in selecting the number of teeth and addendum modification coefficients, and designing the tooth shape. Developing an auto design program is necessary to design various planetary gears more conveniently and quickly. In this study, a planetary gear reducer design software, widely used in various machines and armored vehicles, was developed. This design software can automatically select the number of teeth and modules of the gears, calculate specifications and quickly evaluate its fatigue durability strength and scoring failure according to the planetary gear reducer design theory.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1728-1732
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• 2005

Gear trains are used in many machinery for variable speed ratios. Typical shapes of gear trains are two categories: simple gear trains and planetary gear trains. Generally the methods of the design typical shapes are two way. One of the methods is trailblazing design and the other is selective design in available types. This paper presents the mechanism types when input rotating velocity and output rotating velocity are maintained for useful planetary gear reducers of twelve types. Also, this paper gives the applicable example about rotating velocity of the gear axis, carrier velocity and the organized gear specifications

• Journal of Biosystems Engineering
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• v.41 no.1
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• pp.1-11
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• 2016

Purpose: The gear strength of a new mechanical transmission designed to increase the loading weight of small 4.8 kW tracked agricultural transporters was analyzed. Design improvements to increase the gear strength and reduce the gear weight were proposed after examining the parameters. Methods: Sixteen operators from three regions were surveyed to obtain the usage profile of small 4.8 kW transporters. Gear strength was evaluated by calculating contact stress and tooth root stress using commercial software following ISO 6336. Results: From the strength calculation for each gear pair, contact stress smaller than tooth root stresses were produced in all gear pairs. The safety factors in most cases exceeded 1.0, except in the case of gear pair II in group II. The design life of the transporter using gear pair II in group II was 42% under harsh conditions-thus, this design life needs improvement. A robust design was proposed by examining the relevant parameters (face width and profile shift coefficient) to increase the design life of the transporter. In addition, a lightweight design for gear pair I in group II that was considered overdesigned was proposed by examining the face width to reduce the weight of the drive gear by 42% and that of the driven gear by 30%. Conclusions: The Safety factor for the design life was examined through a gear strength analysis. After examining the relevant parameters, conditions for strength improvement were proposed to increase design life or adjust overdesigned gear. However, load conditions differ depending on the working conditions or user's preferences; therefore, it is necessary to conduct further studies in various regions.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.470-475
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• 1999

Recently as the application of gear drive increases in high-speed and high-loading, the concern of designing multi-stage gear drive is being risen. Until now however, the research of gear drive is focused on single-stage gear drive and the design depends on experiences and know-how of designer and is carried out by trial and error. This research automated the basic design and the configuration design for two and three-stage gear drives which consist of cylindrical gears. In basic design, design is executed with two design processes, which minimize the overall volume of gear, and whose results are compared each other. In configuration design, the positions of gears are determined to minimize the volume of gearbox using the result of basic design and simulated annealing algorithm.

• Journal of the Korean Society of Safety
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• v.18 no.4
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• pp.44-50
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• 2003

Design method for involute bevel gears is developed. The developed gear design system can design the optimized gear that minimize the number of pinion teeth with face tooth. Method of optimization is MS(matrix search) which is developed from this study. Design variables are pressure angle 20., transmitted power, gear volume, gear ratio, allowable contact stress and allowable bending stress. etc. Gears design method developed this study can be applied to the plane, helicopter, printer, machine tools.