http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
A study on the optimum design for the valve plate of a swash plate-type oil hydraulic piston pump
조인성 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.6
Numerous studies have been conducted on hydraulic systems operating under high pressure. However, such systems are difficult to realizebecause of mechanical limitations as a result of tribological problems between relative sliding parts. Design techniques, manufacturingtechniques, and tribological characteristics must be improved or innovated to operate such systems under increased pressure. Thestress distributions and optimum design factors needed to satisfy these requirements under maximum pressure are determined by analyzingthe stress on the valve plate of a hydraulic axial piston pump. This pump is among the most important relative sliding parts. As perthe result of the analysis conducted using an orthogonal array, the extent of the influence of the design factors on maximum stress valueis ordered as follows: [z > M > h > r]. Moreover, the maximum stress value of the optimum model is 13.3% lower than that of the standardmodel. Results also show that the stress characteristic of the optimum model is more stable than that of the standard model.
A study on the pressure ripple characteristics in a bent-axis type oil hydraulic piston pump
조인성,Jae-Youn Jung 대한기계학회 2013 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.27 No.12
To improve the performance of a bent-axis type axial piston pump driven by tapered pistons, it is necessary to know the pressure ripple characteristics. The purpose of this paper is to understand the effect on the pressure ripple characteristics, and to predict by comparing experimental and theoretical analysis results. The simulation model of a bent-axis type axial piston pump is developed in the AMESim environment using the geometrical dimension, and the driving mechanism of the piston pump, such as the stroke of pump, the velocity of piston, the instantaneous volumetric flow, the overlap area of valve plate opening to cylinder bore, the angle of notch, and so on. The results show that theoretical analysis results of the bent-axis type axial piston pump by using the AMESim approximate the pressure ripple characteristic of the test pump, and through this, simulations can be obtained that predict the performance characteristics of a bentaxis type axial piston pump.
조인성,정재연 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.6
In the power steering system of an automobile, the balanced and fixed displacement type vane pump is principally applied to the mainpower source. It is driven by a pulley that is attached to the shaft of the vehicle's engine, and the pulley ratio is about 1:1. The vane pumpcontinuously discharges an outlet flow rate proportional to the rotating speed of the engine. In a vane pump without the flow controlvalve, an increase in the discharge flow rate means a linear increase in the actuator speed. At high speed when the driver rotates the steeringwheel by even a small amount, there is a high risk of an accident due to the quick rotation of the tire joined to the actuator and links. We designed a flow control valve of the fixed displacement and pressure balanced type vane pump for power steering is designed andsimulated using AMESim software. Its theoretical flow characteristics with respect to the rotating speed of the engine are compared andvalidated with experimental data. The results show that the design parameters, such as the flow area, the underlap length, the spool clearance,the main spring stiffness and the spring initial force, largely affect the flow control characteristics.
조인성 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.2
The performance of a reciprocating compressor in refrigeration and air-conditioning systems is influenced by the lubrication characteristicsof the critical sliding components. Improvements in design and performance of reciprocating compressors therefore depend in partupon the lubrication characteristics between the crankshaft and journal bearing. Current studies have explored experimental and theoreticalmethods, yet difficulties arise when applying these results to practical designs in the field. The present study seeks to enhance theenergy efficiency ratio, and to improve the reliability of the reciprocating compressor for refrigeration and air conditioning systems bystudying the influence of boundary conditions on the lubrication characteristics between the crankshaft and journal bearing. The resultsdemonstrate that appropriate boundary conditions, when applied to theoretical analysis, improve both the speed and ease of the designprocess.