• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.3
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• pp.13-18
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• 2011

This study deals with the effect of the honing in SCM420H planetary gears. The hardness, tooth profile, lead and roughness of the gear surface can be improved by honing. Therein, the honing techniques are welcomed especially as one of the physical surface improvement methods. As a result, gear honing reduces vibration and noise, and will increase the life of gear. And gear honing also changes the surface of gear tooth in a short time and price, so it is a very important method in manufacturing industry. But nowadays, it is hard to find the detail information of gear honing. The test gear is a planetary gear which is used in the automotive industry. It is manufactured by the hobbing, shaving, carburizing and honing. This study investigates the effect of honing in surface shape of SCM420H planetary gears, including fatigue strength test and characteristics of honing of SCM420H planetary gears.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.1
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• pp.14-19
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• 2016

Transmission error (TE) is the most important cause of gear noise and vibration because TEs affect the changes of the force and the speed of gears. TE is usually expressed as an angular deviation, or a linear deviation measured at the pitch point and calculated at successive positions of the pinion as it goes through the meshing cycle. Accurate measurement of TE for gear transmission will provide a reasonable basis for gear design, manufacturing processes and quality control. Therefore, in order to study the accuracy of the gear transmission, stability, TE, vibration and noise after gear micro-geometry modification, a gear transmission test rig is proposed in this paper, which is based on the existing technical conditions, by using reasonable testing methods, hardware and a signal processing method. All of the details and the experience can be taken into consideration in the next upgraded test rig.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.5
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• pp.54-59
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• 2012

This study dealt with effect of the grinding in SCM420H planetary gears. The hardness, tooth profile, lead and roughness of the gear surface can be improved by grinding process. Therein, the grinding techniques are widely used especially as one of the physical surface improvement methods. As the results, the gear grinding process reduced vibration and noise, and increased the life of the gear. And the gear grinding improved the surface of gear tooth in a short time and low cost, thus, it is a very important process in manufacturing industry. But nowadays, it is hard to find the detail information of gear grinding process. The test piece is a planetary gear which is used in the industrial machine. The manufacture process of the test piece contains hobbing, shaving, carburizing and grinding. This study investigated the effect of the grinding process to the physiognomy and the fatigue strength of test piece which was made by SCM420H.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.11
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• pp.1949-1957
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• 2003

A hybrid finite element analysis was used to analyze the influence of ring gear rim thickness and spline number on the static properties of a planetary gear system with manufacturing errors. Both of these parameters affected the bearing force and critical stress. The effect of changes in the rim thickness on the load sharing between the gears depended on the type of manufacturing error. Ring flexibility improved the load sharing between planetary gears only in systems with planet tooth thickness or planet tangential errors; for other types of error, ring flexibility worsened the load sharing. To improve load sharing, rim thickness and spline number should be controlled within a specific range. The minimum rim thickness limit should be determined considering not only the critical stress but also the load sharing. The effect of the ring gear boundary condition was more apparent in a system with errors than in a normal system.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.2
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• pp.100-107
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• 2014

Currently, there are many power transmission devices, including gears, friction wheels, chains, and belts. Because the power transmission of gears is most certainin these devices, gears are widely used in different power transmission fields and environments. In accordance with the gear shape, gears can be classified as cylindrical gears and conical gears. A cylindrical gear, which provides a means of power transmission under parallel axis and skewed axis conditions, contains a spur gear, a helical gear and a worm gear. A conical gear, which can be used on a skewed axis as well as parallel and crossed axes, includes a bevel gear(e.g., straight bevel, spiral bevel, hypoid gear) and a conical involute gear(or a bevel oid gear). In this paper, a conical involute gear which utilizes the fabrication method of other involute gears such as spur and helical gears using a CNC hobbing machine is discussed.

• Journal of Mechanical Science and Technology
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• v.18 no.4
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• pp.606-621
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• 2004

A dynamic analysis using a hybrid finite element method was performed to characterize the effects of a number of manufacturing errors on bearing forces and critical tooth stress in the elements of a planetary gear system. Some tolerance control guidelines for managing bearing forces and critical stress are deduced from the results. The carrier indexing error for the planet assembly and planet runout error are the most critical factors in reducing the planet bearing force and maximizing load sharing, as well as in reducing the critical stress.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.4
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• pp.38-43
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• 2011

Industrial reducer is in general use to Deck Crane. High-precision and high-efficient reducer is minimized the power-loss and energy-loss of a machine. So it contribute the price reduction and life extension. Reducer is usually using the Planetary gear reducer. Planetary gear reducer is composed the sun gear, planet gear, internal gear and casing. Industrial reducer's wear and breakage have a short-life. To solve this problem, it is using the profile-shifted-gear or tooth modification. This study was carried out the effect of addendum modification coefficient on tooth fillet bending strength to planetary reducer. Tooth fillet bending stress is calculate. And all parameter were expressed the function of addendum modification coefficient. And then stress concentration factor of tooth fillet curve was express the function of addendum modification coefficient using comparison between theory and finite element analysis.

• Journal of Mechanical Science and Technology
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• v.18 no.11
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• pp.1978-1988
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• 2004

Hybrid finite element analysis was used to analyze the influence of bearing stiffness on the static properties of a planetary gear system with manufacturing errors. The effects of changes in stiffness were similar for most of the manufacturing errors. State variables were most affected by the stiffness of the planet ,bearings. Floating either the sun or carrier helps to equal load sharing and minimizes the critical tooth stress. The effects of a floating sun and carrier are similar, but it is not recommended that both float, because this can induce greater critical tooth stress. Planet bearing stiffness should be optimized. Both load sharing and critical tooth stress should be considered to determine optimal bearing stiffness.

• International Journal of Precision Engineering and Manufacturing
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• v.3 no.3
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• pp.50-55
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• 2002

A roller gear cam mechanism is presented. It consists of two or more plate cams with particular teeth, called Conjugate Cam Tooth (CCT) and a turret with axially located rollers. A practical and available configuration has been found out by synthesizing its parameters. The profile equations of the conjugate cam are derived by using a relative velocity method. A program fur the design automation of shape of the conjugate cam and the motion simulation of this kind of mechanism has been deve1oped using the derived formulae with C++ language. Finally, an example is given.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.05a
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• pp.381-385
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• 2006

This research introduces easy tool manufacturing method regarding tool manufacturing procedure. In the conventional method, wire cutting machining and lapping operation of corner and render region were performed after shrink-fitting to ensure the accuracy of gear profile. But lapping operation is very difficult due to corner and render is located deep inside of die. In this research, wire cutting operation was performed after $1^{st}$ ring was shrink-fitted to ease lapping operation and increase the accuracy of corner radius. Before $2^{nd}$ ring fitting, lapping was completed. Elastic deformation amount due to $2^{nd}$ ring fitting and cold forging was calculated through finite element analysis and wire cutting specification was offset in that amount. Comparison of gear dimension between analysis and forged part ensures the validity of new manufacturing methods.