• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.74-79
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• 2019

The military vehicle produces electric power through an engine-integrated serial hybrid generator that is connected to the engine and does not have a separate generator installation space. However, depending on the mechanical characteristics of the connection between the generator and the engine, iron oxide for internal rusting and lubrication grew scattered. The iron oxide is adhered to the starter to deteriorate the starting performance, and there is a problem that the noise of the leg due to wear of the gear is increased. To solve this problem, the connection spline material and the surface treatment of the engine were improved and the shape was changed to a grease sealing type to prevent the generation of iron oxide inside. As the shape of the generator connector composing the shafting system was changed, the integrity of the structure was confirmed through the torsional endurance test. In addition, through the actual vehicle load test, it was verified that no corrosion occurred during the target life span without internal corrosion. It was confirmed that the anti-scattering structure of the grease effectively suppresses the generation of iron oxide, thereby reducing the noise generated from the generator. In this paper, we propose a fundamental solution to the degradation of the starter and the noise generation by preventing the back corrosion caused by the serial hybrid generator installed between the engine and the transmission.

• Journal of Power System Engineering
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• v.12 no.3
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• pp.38-43
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• 2008

The usage of electric forklift truck is gradually increasing due to the convenience at conveying and arranging the materials in the industrial field. In this study, the author designed and suggested the optimum driving system and load tester which both of them are the most important part of the forklift truck. The planetary gear is chose to driving system because it makes big power even though the motor size is small. The gear teeth of planetary gear were designed and the designed planetary gear was tested considering the yield strength and the abrasion of gear teeth. The B-Type electric brake which consists of multiple plates and operates with non-magnetic type was connected with a single shaft in the driving system. So, it can be applied at the sudden braking situation which has the torque increment. And it has the compact size and excellent durability Load tester can give the various levels of load to the planetary gear of driving system in the electric forklift truck and it can also measure the levels of the load which were applied. Therefore, we can measure the noise, torque and perform the durability, vibration tests using load tester. It will be economical because many kinds of test can be performed using reasonable priced load tester The driving system of electric forklift truck which has sufficient competitive can be manufactured using our designed planetary gear reducer with reasonable price. The designed load tester can use for checking the performance of other reducers, as well.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.256-262
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• 2016

This study performed the back-pressure cold forging analysis to minimize the non-forming area of gear teeth for the output hub and reaction hub in automatic transmission. Two important factors of the back-pressure cold forging process, the load of the punch and the backup force applied to the sleeve, were determined through displacement control analysis. The non-forming area of the gear teeth was compared with both cases of the displacement control analysis and load control analysis, and their solution is similar to the measuring result of a real workpiece. The results show that the load of the punch is dependent on the reduction area of the workpiece, and the backup force applied to the sleeve is determined with regard to the cross-section-area of sleeve. This analysis procedure can be useful and effective in determining the manufacturing condition of the back-pressure cold forging process to minimize the non-forming area.

• Analytical Science and Technology
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• v.27 no.1
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• pp.41-59
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• 2014

The aims of this work were the identification and the classification of fresh lubricants and used engine oils of vehicles for the application in forensic science field-80 kinds of fresh lubricants were purchased and 86 kinds of used engine oils were sampled from 24 kinds of diesel and gasoline vehicles with different driving conditions. The sample of lubricants and used engine oils were analyzed by GC/MS. The Bayesian model technique was developed for classification or identification. Both the wavelet fitting and the principal component analysis (PCA) techniques as a data dimension reduction were applied. In fresh lubricants classification, the rates of matching by Bayesian model technique with wavelet fitting and PCA were 97.5% and 96.7%, respectively. The Bayesian model technique with wavelet fitting was better to classify lubricants than it with PCA based on dimension reduction. And we selected the Bayesian model technique with wavelet fitting for classification of lubricants. The other experiment was the analysis of used engine oils which were collected from vehicles with the several mileage up to 5,000 km after replacing engine oil. The eighty six kinds of used engine oil sample with the mileage were collected. In vehicle classification (total 24 classes), the rate of matching by Bayesian model with wavelet fitting was 86.4%. However, in the vehicle's fuel type classification (whether it is gasoline vehicle or diesel vehicle, only total 2 classes), the rate of matching was 99.6%. In the used engine oil brands classification (total 6 classes), the rate of matching was 97.3%.