• Journal of Sensor Science and Technology
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• v.27 no.2
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• pp.126-131
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• 2018

Unlike the hydraulic power steering (HPS) system, which operates by the high pressure of a fluid obtained from the engine power, the motor-driven power steering (MDPS) system uses an electric motor to steer the wheel without consuming engine power. To steer the wheel with an electric motor, a worm wheel and a worm gear rotating between the steering shaft and motor are required. Any imperfection during the construction of an MDPS system or in a composing part creates noise and vibration, which can be sensed by a driver. To solve the noise and vibration problems, each part must be designed to not resonate with other parts. In this work, we developed the measurement and analysis systems to obtain the noise and the vibration of an automobile MDPS system. A signal analyzer was equipped with a 96 kHz, 24-bit ADC and a 150 MHz digital signal processor. The predetermined threshold value of the vibration in the MDPS system was used to determine the pass/fail, and the results were displayed on the screen. Our system can be used in the fabrication line to swiftly determine any imperfections in the MDPS system construction.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.2
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• pp.335-338
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• 2012

Recently, the energy has been used much more than ever, but there has been many problems including atmospheric pollution. So we need alternative energy resources, which are solar heat, solar light, wind power, small water power, etc. The field, which is most popular these days, is the energy source by solar light which transform electric energy using the solar cell and it is available with many researches. In this paper, we manufactured the solar power generation system over 90W using solar module which was 9.90V for Voc, 0.93 A for Isc, 8.64 V for Vmp, 0.75 A for Imp, 6.5 W for power. System was controlled by step motor with worm gear to operate optimum condition between $0^{\circ}{\sim}70^{\circ}$ angle. This system was very effective in tracking space use because it need less space than general solar module.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1987.11a
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• pp.47-74
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• 1987

현재 엘리베이터용 worm gear의 wheel로써 가장 많이 사용되고 있는 것은 인청동이다. 일반적으로 청동에 인의 함량이 0.05% - 0.5% 정도 잔류하는 인청동은 용탕의 유동성이 좋아지고, 합금의 강도, 경도가 증가하며 내마모성, 탄성이 증가한다. 또한 P는 극소량 Cu 중에 고용하나 그 외에는 경하고 취약한 $Cu_3P$상으로 존재하고, P의 함유에 따라 Sn의 고용도가 저하하므로 주조 조직중에 $\delta$상($Cu_{31}Sn_8$)이 증가하여 Sn을 증가한 때와 같이 경도가 커지는 효과가 있다. 이같이 기지상 중에 간단한 3원 공정부 ($\alpha + \delta + Cu_3P$)상이 산재하여 있어 이것이 마찰상대면을 지탱하여 내마모 역할을 하기 때문에 인청동이 내마모 재료로써 많이 쓰이고 있는 것이다.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.227-230
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• 2003

The results of the field tests with the prototype of the improved screw type show that the opening torque was $5N{\cdot}m$, 64% decreased compared to $14N{\cdot}m$ of the existed diversion gates. Moreover, there were no any rust as well as physical changes with various weather condition. While the operating times of the conventional screw and worm gear typed diversion gates were 233sec and 495sec, respectively, the operating time of the improved screw type was only 32sec, only 13.7% and 6.5%, respectively, of them. The amount of leakage was 0.4 liter per minute for the improved screw typed diversion gate while the conventional gate was shown 1.5liter per minute according to gap, corrosion, defect, etc.

• Journal of Power System Engineering
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• v.12 no.1
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• pp.80-86
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• 2008

A motor cylinder apparatus is used to transfer a load in industrial applications. The apparatus is composed of a motor and power transmission elements such as worm gear and screw. In this case, the nonlinear friction of the transmission elements has a bad influence on the position control performance. To overcome this problem, the position control system consists of a feedback controller to achieve nominal control performance and a disturbance observer to compensate nonlinear friction. Especially the filter of a disturbance observer is designed from viewpoint of robust stability. Finally, the simulation result shows that the proposed control system is effective for the disturbance elimination as well as the friction compensation.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2778-2780
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• 2003

본 논문에서는 모터구동밸브의 모터 토크를 전기적인 신호만으로 예측하고, 계산된 모터 토크신호를 주파수영역에서 분석하여 Motor Speed, Slip pole 주파수, WGTM(Worm Gear Tooth Mesh)과 같은 MOV의 기계적 특성 성분을 확인하였다. 또한 모의 고장 실험을 통해 MOV 기계적 고장이 이 특성성분의 변화로 나타나는 것을 확인하므로, 이 정보를 MOV의 고장 감시 기술로 적용할 수 있다. 아울러 전기 신호를 이용하여 Condition Monitoring 기법을 개발하고, MOV 고장 감시 Software를 개발하므로, MOV 주기적 확인에 대비한 규제검증 기술 및 정보를 제공하고자 한다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.11
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• pp.1327-1334
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• 2012

This study shows the conformance-based design results of a fourth-order dynamic actuator showing a performance variation caused by variation in the components as well as aero-induced disturbances. The actuator comprises a BLDC motor, spur gear and worm gear assembly, and canard. The actuator performance was evaluated by using time-variant angle information of the canard. Based on the response surface models, critical system variables were screened using F-tests, and then, the performance was approximated as a function of the variables because it is difficult to determine the performance of a high-order dynamic system as a function of system variables through analytical approaches. In this study, the conformance of uncertain performance to the specification was defined as a probability measure. The design variables obtained by optimizing the measure can provide actuator performance conforming to the specifications considered, even though there is a variation in both the components and the aero-induced disturbances.

• Tribology and Lubricants
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• v.4 no.1
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• pp.56-68
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• 1988

The wear resistance of P-bronze which is widely used as worm gear material was investigated. In order 1o study the effect of additional elements on the wear resistance of Pbronze, the applied load and sliding time were selected as variables, and SCM4, were used as against metal. The addition of Fe improve wear resistance, for it precipities hard Fe$_3$ P phase and the work hardening coefficients are lowered due to decreasing solubility of P. When Fe is added in conventional P-bronze, the alloy is rather sliding than forming wear debris by frictional force during wear test. Experimental results indicated that the wear mechanisms for P-bronze are mainly consisted of abrasive wear due to Beilby layer forming mechanism and adhesive wear due to thermally activated wear mechanism. Moreover, the weight loss is decreased in accordance with increasing load and time. However the rate of wear loss is decreased as the sliding time is increased.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.11
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• pp.2759-2764
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• 2014

Smoke detector is commonly used to reduce fire detection time. However, technical problems regarding its inaccuracy of laser beam-receiving point on the surface of the sensor associated with incoming interference are identified when the laser transmitter and receiver are installed at a distance of about 100m. In this paper, we propose the auto focus alignment algorithm with high precision to adjust tilting angle of lasers caused by environmental interference so that solve existing issues using multi-level worm gear set.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.1
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• pp.49-55
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• 2015

In this study, among in various scenarios of the duration degradation of the fuel cell, countermeasures for the cathode carbon carrier oxidation and the deactivation of catalyst by hydrogen / air interface formation have been studied. so the system was applied to the air cutoff valve. In terms of the component, the cold start performance, electrical stability, the airtight performance were mainly designed and their performance was confirmed. And in terms of the system, the air electrode flow is blocked off, so the oxygen concentration drops when system is powered off, As a result, By reducing unit cell voltage which affect the durability of the fuel cell reached up to 0.8V, the improved durability of the fuel cell was confirmed.