• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.4
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• pp.419-432
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• 2010

Various torque generating devices have been developed and employed to apply a proper torque. These devices are usually calibrated by the manufacturer to apply appropriate torque levels for their specific implants and attachments. The purpose of this investigation was to determine and compare the accuracy of the torque controllers. In this study, 4 types of torque controllers were used; torque limiting device(TLD), torque indicating device(TID) and contra angle torque driver(CA), electronic torque controller(ETC). Digital torque gauge was employed to measure the de-torque value. Thirty cycles of tightening and loosening were repeated with each torque controller. All implant torque controllers have shown slight errors and deviations. The contra angle torque driver exhibited the most accurate data. In the limitation of this study, it would be recommended that the implant torque controllers should be checked whether uniformed and precise torque can be generated and a measuring error should be corrected.

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.2
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• pp.157-168
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• 2008

Tightening of the screws in implant restorations should be accurate and precise. If applied torque is too low, screw loosening would be occurred. With too high torque, the screw fracture might take place. Various torque generating devices are developed and employed to apply a proper torque. The purpose of this investigation was to determine and compare the accuracy of the torque controllers. In this study, 4 types of torque controllers were used; electronic torque controller, torque limiting device, torque indicating device and contra angle torque driver. Digital torque gauge was employed to measure the de-torque value. Thirty cycles of tightening and loosening were done with each torque controller. All implant torque controllers have shown slight errors and deviations. The torque liming device exhibited the most accurate data. No significant difference was found among the mean de-torque values of the electronic torque controller, torque indicating device and contra angle torque driver. In the limitation of this study, it would be recommended that the implant torque controllers should be checked whether uniformed and precise torque can be generated and a measuring error should be corrected.

• Transactions of The Korea Fluid Power Systems Society
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• v.7 no.1
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• pp.6-10
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• 2010

A measurement of very high torque for track drive unit in construction equipment is usually in difficulties due to the requirement of a torque meter with high capacity, and the limitation of geometry for an experimental set-up. To improve the troublesome problem, a new device was proposed, where a torque transmitted through the torque arm can be measured by load cells attached at each torque arm. The experimental set-up of the new device was carried out in order to measure the torque values for a mechanical feedback type planetary gear box, in which the power flow circulates itself in a closed-loop. The new device enables to measure torque values of 60,000Nm. Additionally, the measured values were estimated statistically in the aspect of their repeatability and reproducibility, so that an acceptable behaviour as a measuring device can be confirmed.

• Journal of the Korean Society of Propulsion Engineers
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• v.7 no.3
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• pp.53-60
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• 2003

A test stand was developed to measure static performance of a reciprocating engine on the ground, related to the small aircraft being developed by KARI. The test stand consists of an apparatus to install and operate a pusher-type propulsion system and a data acquisition system to process many performance parameters including engine torque and propeller thrust as well as monitoring of the engine operations. First, the performance data from the basic operation tests were compared with the original engine data so the capacity of the test stand was verified. Engine performance tests were carried out with various test conditions through three stages, and it was measured and analyzed that the manifold pressure, the torque, and the back pressure of the engine, and the static thrust of the propeller.

• Journal of Power System Engineering
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• v.12 no.5
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• pp.20-26
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• 2008

양산되는 승용차용 토크 컨버터 내부의 유동을 LDV 측정 기술을 이용하여 정량화했다. 속도비 0.4와 0.8 경우에 대한 속도 측정을 통해 임펠러 유로 중간과 출구 영역의 질량 유동율 특성을 분석했다. 측정 단면의 속도 분포는 유로의 위치와 속도비에 따라 많은 차이를 보이며, 특히 속도비 0.8 조건에서 임펠러 유로 중간영역 흡입면 부근의 유동은 유동박리에 의한 재순환 현상을 나타내며, 이와는 대조적으로 출구 영역에서는 흡입면을 따라 역류 현상이 발생한다. 임펠러 유로 내부의 유동은 각 영역에서 속도비에 따라 개별적 유동 특성을 보인다. 질량 유동율은 모든 속도비와 측정단면에서 주기적인 변화를 보이며, 또한 터빈의 순간적인 위치가 임펠러 유로 측정단면의 질랑 유동율에 매우 큰 영향을 미치는 것이 밝혀졌다 따라서 토크 컨버터 임펠러의 유로 방향 유동 특성 변화는 컨버터 설계에 중요하게 고려되어야 할 것으로 보인다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.227-230
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• 2008

Movable nozzle with a flexible seal have been used for Thrust Vector Control of the Solid Rocket Motor. The Hydraulic Testing Machine is consisted of Chamber, Actuator, Counterpotentiometer, and evaluates performance of Flexible seal for spring torque and axial compression. The qualification test of Flexible seal was conducted on design condition. A study fix up method of formulation, operation, inspection on Hydraulic testing machine.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.4
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• pp.300-306
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• 2013

Purpose: This study was to evaluate the accuracy of how to use the Mechanical Torque-Limiting Devices. Materials and methods: Three different implant manufacturers (Dentium, Osstem, Shinhung) were prepared for each two implant torque controllers. Divided into two groups depending on the method used for removal torque was measured. Repeated measures of ANOVA test (${\alpha}=.05$) was used as statistics to evaluate the effect of repeated loading number on the removal torque. Independent t-test was used to evaluate the difference in removal torque of two groups. Results: The removal torque significantly decreased as the number of loading repetition increased (P<.05). There was significant difference between two groups. Conclusion: Loosen the handle part of the implant torque controllers spring resilience to recover one group compared to the group that did not, showed a little more closed to the reference value.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.5
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• pp.507-515
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• 2015

This study was conducted to develop and verify a torque application device for use in a mechanical power-circulation test rig for 5.5 MW wind turbine gearboxes. The design and analysis of the torque application device was conducted. In addition, the torsional stiffness of the test rig was calculated using the rotational angle measurements for each of the components. The calculated stiffness of the test rig was $231.13kN{\cdot}m/rad$ for a clockwise torque application. The rated torque can be applied when the stiffness of the gearbox is greater than $1,064,400kN{\cdot}m/rad$ for a clockwise torque application. Because of the limited rotational angle of the test rig, the potential application of the rated torque is determined according to the torsional stiffness of the test gearbox.

• Journal of Aerospace System Engineering
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• v.15 no.5
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• pp.60-71
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• 2021

Propeller performance measurement system for commercial propeller was designed and applied to the wind tunnel test for 3 commercial propeller models with diameters of 30 inch. The thrust and torque of the propeller was directly measured by using 6-components balance installed on the rotating axis. The measurement system was validated by using wind tunnel balance calibration equipment. Propeller test stand including measurement and rotating system was validated by using QTP propeller. In the hovering condition, we compared the performance test results and the specifications of the commercial propeller provided by the manufacturer and confirmed that there are differences in the thrust and the torque. We measured the propeller performance with various wind speeds, propeller models and angles of attack and was summarized by thrust coefficients. We confirmed that the trend of the thrust coefficients was different in the low angle of attack and high angle of attack. An aerodynamics database that can be used for future aerodynamic design of an unmanned aerial vehicle was secured.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.7-7
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• 2017

본 연구는 수확 작업에 따른 농업용 트랙터의 차축 부하 분석을 목적으로 수행되었다. 트랙터의 부하 측정을 위한 부하 계측 시스템은 4개 차축의 토크 측정을 위한 휠 토크미터, 부하 데이터 수집을 위한 데이터 수집장치, 토크미터에 전원을 공급하기 위한 전원공급장치, 트랙터 배터리를 이용하여 노트북 및 전원공급장치에 전원을 공급하기 위한 인버터, 데이터 처리를 위한 노트북으로 구성하였다. 본 연구에서는 부하계측을 수행하기 위해 동양물산(주)의 60 마력급 트랙터 T623을 사용하였다. 부하 분석은 수확 작업에 따른 주행 단수 별 데이터를 이용하여 통계분석을 수행하였다. 수확 작업 시 L2단에서 좌측 전륜에서의 최대, 최소, 평균, 표준편차 토크는 각각 1735.44, 818.36, 1201.38, 175.53 Nm로 나타났으며, 우측 후륜에서는 3685.11, 1971.68, 2981.80, 258.36 Nm로 나타났다. L3단에서 좌측 전륜에서의 최대, 최소, 평균, 표준편차 토크는 각각 1580.94, 701.06, 1007.93, 125.11 Nm로 나타났으며, 우측 후륜에서는 3239.57, 1735.44, 2472.11, 307.85 Nm로 나타났다. 트랙터의 차축 부하는 L2단에서 L3단으로 작업속도가 증가함에 따라 좌측 전륜에서 약 0.83배, 우측 후륜에서 약 0.82배 감소하는 것으로 나타났다. 향후에는 Romax_Designer (Version 17, Romax Technology, UK)을 사용하여 작업 부하에 따른 트랙터 트랜스미션 해석을 하여 트랙터 PTO 최적설계 가능성을 제시할 계획이다. 정격 출력 조건에서 시뮬레이션을 진행하여 트랙터 트랜스미션을 설계하면 안전성을 확보할 수 있지만 최적설계를 위해서는 실제 포장시험 데이터를 이용한 시뮬레이션이 필요하다고 판단된다.