• 동력기계공학회지
• /
• 제11권4호
• /
• pp.65-71
• /
• 2007

According to the survey, abnormal condition of the system is the main source for interrupting an elevator service, especially faults in worm gears used for the traction machine. Worm gear is popularly used in traction machine for middle and low speed elevators. Elevators need high reliability and stability, because they are closely related to human life. Usually, traction machine is applied to drive the elevators that have height about 35 m and it is an important mechanical unit for riding quality in elevators. There are some research results about types of vibration fault for worm gear in International Association Elevator Engineers (IAEE). But this study concerns with diagnosis of various faults in elevator worm gear using vibration signal. The analysis of fault characteristics is compared with previous researches in traction machine.

• 한국산업융합학회 논문집
• /
• 제20권5호
• /
• pp.359-364
• /
• 2017

A machine such as bean crusher machine is subjected to different loads and vibration. Due to this vibration there will be certain deformations which affect the performance of the machine in adverse manner. This paper proposed a vibration analysis of bean crusher machine using ANSYS. The Finite Element Method (FEM) analysis is carried out to study the effect of vibration on the structure in order to ensure the safety. This work helps the machine developer make a better product at the early design stage with lower cost and faster development time. To do this, firstly, using Inventor, a CAD model is prepared. Secondly, the analysis is to be carried out using ANSYS 15. The modal analysis and random vibration analysis of the structure was conducted. The analysis shows that the proposed design was successfully shows the minimum deformation when the vibration was applied in normal condition.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2003년도 추계학술대회논문집
• /
• pp.549-555
• /
• 2003

The technology of machine condition monitoring is used effectively to detect the machine faults at an early stage using different machine quantities, such as current, voltage, temperature and vibration. Induction motors are most widely used to drive pumps, compressors and fans in industrial drives. This paper presents approach to data fusion using Dempster-Shafer theory because only one technique has uncertainty. So we can obtain advanced accuracy of the machine fault diagnosis. Vibration and current quantities are applied to diagnose three-phase induction motor.

• 한국정밀공학회지
• /
• 제32권1호
• /
• pp.9-16
• /
• 2015

The machining-chatter stands for a sudden relative vibration appeared between a material and a tool while processing with a machine. This chatter is key factor that seriously affects the quality of processed materials as well as being a factor which causes serious damages to the tool and the machine. This study is related to the monitoring and smart control of chatter problem that can compensate machining-chatter faster and produce processed goods with more precision by autonomous compensation. The above-mentioned machining-chatter compensator includes the chatter vibration sensor and the chatter compensator that estimates the compensation value according to the sensor detecting the chatter vibration of machine-tool and the chatter vibration detected from the sensor while having a feature of being organized by interlocking with the machine-tool controller.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2007년도 춘계학술대회 논문집
• /
• pp.141-142
• /
• 2007

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 2005년도 춘계학술대회 논문집
• /
• pp.288-293
• /
• 2005

A earn profile grinding machine is a mandatory machine tool for manufacture of high precision contoured cam. Experimental evaluation of modal analysis is an effective tool to investigate dynamic behavior of a machine. This paper presents the measurement system and experimental investigation on the modal analysis of a grinding machine. The weak part of the machine is found by the experimental evaluation. The results provide structure modification data for good dynamic behaviors. And safety of the machine was confirmed by the modal analysis of modified machine design. Finally, the cam profile grinding machine was successfully developed.

• Industrial Engineering and Management Systems
• /
• 제4권2호
• /
• pp.192-197
• /
• 2005

Among many amplitude parameters, Kurtosis (4-th normalized moment of probability density function) is recognized to be the sensitive good parameter for machine diagnosis. Kurtosis has a value of 3.0 under normal condition and the value generally goes up as the deterioration proceeds. In this paper, simplified calculation method of kurtosis is introduced for the analysis of impact vibration with one sided affiliated impact vibration which occurs towards the progress of time. That phenomenon is often watched in the failure of such as bearings’ outer race. One sided affiliated impact vibration is approximated by one sided triangle towards the progress of time and simplified calculation method is introduced. Varying the shape of one sided triangle, various models are examined and it is proved that new index is a sensitive good index for machine failure diagnosis. Utilizing this method, the behavior of kurtosis is forecasted and analyzed while watching machine condition and correct diagnosis is executed.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 1997년도 추계학술대회논문집; 한국과학기술회관; 6 Nov. 1997
• /
• pp.119-131
• /
• 1997

Ball type automatic balancer is used to reduce the vibration caused by unbalance of rotor. In this study, A analytic modeling of a front loaded washing machine with ball type automatic balancer has been suggested theoretically and ADAMS has been used to analyze the dynamic characteristics of automatic balancer. It is found from simulation and experimental results that the automatic balancer suppress the steady state vibration of the washing machine effectively. The test results match well with the simulation results of ADAMS, thereby the dynamic model of ADAMS can be used as virtual prototype to predict the vibration characteristics which could be changed by the modification of design variable and can reduce the design cycle sharply. To maximize the balancing effect of automatic balancer, the friction between balls and race and the deviation between geometric center and rotation center of drum need to be minimized and the optimum design for the stiffness of flange shaft and the angular acceleration of drum should be achieved.

• 동력기계공학회지
• /
• 제18권3호
• /
• pp.20-28
• /
• 2014

Most washing machines are now produced as a drum-type, where a washing drum mounted on a suspension system with springs and dampers, to minimize the transmittance of the vibration from the drum to the cabinet. The purpose of this paper is to develop optimized suspension system of the drum washing machine which minimizes transmission of disturbing vibration and force. In this paper, a method for optimizing suspension system of the drum washing machine is presented using ADAMS. The design variables to optimize are extracted using Sequential Quadratic Programming(SQP) in ADAMS. To evaluate optimized spring constants and damping coefficients of the drum washing machine, simulation was done to compare the vibration attenuation performances before and after the optimization. The results of simulation show that the optimized suspension system has better performance than before the optimization.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2007년도 추계학술대회논문집
• /
• pp.1212-1217
• /
• 2007

ATM(automated teller machine) is a machine which can deposit and withdraw money directly. For effective transfer of bills in the machine, crown belts are used. In this paper, the transverse vibration of crown belt is investigated. The equation of motion of the belt is derived using Lagrange's equation. Galerkin's method is applied to convert the partial differential equation to the ordinary differential equations. Experimental investigations are performed on the belt system with the variation of pulley type, eccentricity, and tension. The results of numerical analysis show in good agreement with the experimental results.