• Title/Summary/Keyword: 컨트롤 밸브

Search Result 123, Processing Time 0.021 seconds

Development of a Concrete Pump Truck's Core Pump Model and Its Validation (콘크리트 펌프트럭의 코어펌프 해석모델개발 및 신뢰성 검토)

  • Park, Sung Su;Noh, Dae Kyung;Lee, Geun Ho;Lee, Dae Hee;Jang, Ju Sup
    • Journal of Drive and Control
    • /
    • v.15 no.2
    • /
    • pp.1-8
    • /
    • 2018
  • This study is a first step toward reducing surge pressure, and it has another purpose, which is to developing an analysis model which can closely analyze a hydraulic circuit and be used in design. For development of analysis model, SimulationX, a commercial program, is used. The study progress methods are as follows. By analyzing the structure and operating mechanisms of each part of the hydraulic system of the pump truck and referring its parameters, develop a single component model. Assemble the developed single component model, and make an overall analysis the model. By comparing the similarities between the developed model and the actual system's test results, validate the reliability of the analysis model.

Experimental Analysis of Clutch-Fill Parameters for Automatic Transmission (자동변속기 클러치 충전제어 파라미터의 실험적 특성분석)

  • Jung, G.H.;Park, D.H.
    • Journal of Drive and Control
    • /
    • v.11 no.3
    • /
    • pp.47-54
    • /
    • 2014
  • Clutches are an integral part of the automatic transmission for changing gears. Modern automatic transmissions make extensive use of wet multiple-disc clutches employing hydraulic actuation mechanism with electronic control. Although nowadays, highly advanced shifting algorithm implements the superior shift quality and transmission efficiency, its performance should be based on smooth, reliable engagement with a reasonably durable friction material as well as stable clutch piston dynamics. Particularly, clutch filling control is the crucial part of shifting process because only the open-loop control is available due to the lack of measurement. In this paper, the effect of clutch-fill control parameters on clutch piston dynamics is experimentally investigated by using clutch piston test equipment which enables the clutch piston to actuate similar to real shifting conditions. The experimental analysis results can be expected to be utilized for the calibration of proportional solenoid valve as reference current profile data in vehicle test.

Development of Drifter's Hydraulic System Model and Its Validation (드리프터의 유압시스템 해석모델 개발 및 신뢰성 검토)

  • Noh, D.K.;Jang, J.S.;Seo, J.H.;Kim, H.S.;Park, S.H.
    • Journal of Drive and Control
    • /
    • v.11 no.3
    • /
    • pp.14-21
    • /
    • 2014
  • The goal of this study drifter is to understand the operating mechanism of a drifter and to suggest a reliable analysis model which can be used for evaluating the drifter's performance from the viewpoint of impact frequency and energy. For this, the working principle of drifter and functions of its main components were analyzed, and a simulation model was developed based on the analysis. The model was validated using experimental tests on a test-bench. A comparative study of simulation and experimental results indicated that the suggested model accurately represents the real drifter system in terms of impact frequency and impact energy per blow.

Development of Transmission Simulator for High-Speed Tracked Vehicles (고속 무한궤도 차량용 변속기 시뮬레이터 개발)

  • Jung, Gyuhong
    • Journal of Drive and Control
    • /
    • v.14 no.4
    • /
    • pp.29-36
    • /
    • 2017
  • Electronic control technologies that have long been developed for passenger cars spread to construction equipment and agricultural vehicles because of its outstanding performance achieved by embedded software. Especially, system program of transmission control unit (TCU) plays a crucial role for the superb shift quality, driving performance and fuel efficiency, etc. Since the control algorithm is embedded in software that is rarely analyzed, development of such a TCU cannot be conducted by conventional reverse engineering. Transmission simulator is a kind of electronic device that simulates the electric signals including driver operation command and output of various sensors installed in transmission. Standalone TCU can be run in normal operation mode with the signals provided by transmission simulator. In this research, transmission simulator for the tracked vehicle TCU is developed for the analysis of shift control algorithm from the experiments with standalone TCU. It was confirmed that shift experimental data for the simulator setup conditions can be used for the analysis of control algorithms on proportional solenoid valves and shift map.

A Study on Driving Algorithm and Communication Characteristics for Remote Control of Mini Excavator (소형 굴삭기의 원격제어를 위한 주행 알고리즘 및 통신특성에 관한 연구)

  • Jeong, Jin Beom;Kim, Kyung Soo
    • Journal of Drive and Control
    • /
    • v.15 no.4
    • /
    • pp.81-90
    • /
    • 2018
  • Indoor construction site such as building demolition sites, tunnel, vinyl house, and cattle shed are subject to various risk factors such as falling stones, soot and bad odors. However, most of the mini excavators have no cabin that can protect the driver from such risk factors. Therefore, researches on remote control technology of construction equipment are actively conducted as a method for protecting the driver from the risk factors occurring in the working environment. For effective remote control, it is necessary to be able to control the travelling and work using a portable small transmitter. However, due to the limitation of the size of the transmitter, complex operation control is required to control two or more actuators with a single joystick. Also, it is essential to check how remote control characteristics change in various environments such as distance, signal strength, obstacle. Therefore, in this study, an algorithm that can control two actuators simultaneously with a single joystick signal was developed, and a communication method suitable for indoor and outdoor mini construction equipment by analyzing experimentally how the remote control characteristics vary according to various work environments and telecommunication methods proposed.

Design of Creep Function for Forklift Automatic Transmission (지게차 자동변속기 저속주행기능 설계)

  • Jung, Gyuhong
    • Journal of Drive and Control
    • /
    • v.18 no.2
    • /
    • pp.46-55
    • /
    • 2021
  • A forklift is a powered industrial vehicle used to lift and move materials over short distances. Nowadays, almost all forklifts are equipped with an automatic transmission due to its improved operator comfort and increased productivity. Thanks to marked improvement of transmission control unit equipped with highly-advanced microcontrollers, recently developed automatic transmission for forklift have various auxiliary functions such as creep, auto retardation, and automatic shift with excellent shift quality. This paper deals with the creep function which enables one to maneuver a forklift at the designated low speed by slip control of clutches. The design of creep function was based on four modes of creep operation depending on the status of the operator's shift lever and accelerator pedal. Control algorithms and control parameters for each mode were designed to achieve the desired static and dynamic performance. Vehicle test for the designed creep function was carried out with an independently developed embedded controller. Test results confirmed good creep speed control without speed error at a steady state with a mild shift shock during mode changes by stepping or releasing the accelerator.

Improving Hydraulic System Design by Analysis Model of a Self-propelled Spinach Harvester (자주식 시금치 수확장치 해석모델을 활용한 유압시스템 개선 설계 제안)

  • Noh, Dae Kyung;Lee, Dong Won;Lee, Jong Su;Jang, Joo Sup
    • Journal of Drive and Control
    • /
    • v.19 no.1
    • /
    • pp.69-75
    • /
    • 2022
  • This study aimed to develop solutions for the intermittent performance deterioration of self-propelled spinach harvesters through analysis model. The study was conducted in the following manner. First, changes in performance deterioration and surplus flow, which result from oil temperature changes, were analyzed by simulating actual sequential harvesting movements, which involve driving with actuators operated simultaneously, by analysis model developed in a previous study. Second, fundamental solutions for surplus flow problems were presented. Third, the solutions were applied to a virtual environment to present their practicality and quantitative effects. The two solutions based on the study results were as follows. First, a closed center-type directional control valve was applied to the hydraulic circuit. Second, an unloading system was set up through an on-off solenoid valve.

Reliability Analysis on Safety Instrumented System by Using Safety Integrity Level for Fire.Explosion Prevention in the Ethyl Benzene Processes (Ethyl Benzene 공정에서 화재.폭발방지를 위하여 안전건전성수준을 이용한 안전장치시스템의 신뢰도 분석)

  • Ko, Jae-Sun;Kim, Hyo;Lee, Su-Kyoung
    • Fire Science and Engineering
    • /
    • v.20 no.3 s.63
    • /
    • pp.1-8
    • /
    • 2006
  • The purpose of this work is to analyze quantitatively if the safety instrumented system(SIS) like the pressure safety valves(PSV) in the processes of ethyl benzene plant have been designed relevantly to the safety integrity level because overpressure in the benzene or ethyl benzene columns causes the explosive reactions, fires and reactor explosions. The safety integrity level(SIL) 3 has been adopted as a target level of SIS based on the general data of the Probability of Failure on Demand of PSV, $1.00E-4{\sim}1.00E-3$. The standard model of the reliability has been set up and then the fault tree analysis of it has been carried out to get the PFD of SIS, and the results show 8.97E-04, 5.37E-04, 5.37E-04 for benzene prefractionator column, benzene column and EB column, respectively. Thus, we conclude that the SIS is designed to fulfill the condition of SIL3, and when the partial stroke test for the control valve are carried out every sixth month, the SIS of each column is expected to increase its reliability up to $22{\sim}27%$.

Risk Assessment and Safety Measures for Methanol Separation Process in BPA Plant (BPA 공장의 메탄올 분리공정에서 위험성 평가 및 안전대책)

  • Woo, In-Sung;Lee, Joong-Hee;Lee, In-Bok;Chon, Young-Woo;Park, Hee-Chul;Hwang, Seong-Min;Kim, Tae-Ok
    • Journal of the Korean Institute of Gas
    • /
    • v.16 no.3
    • /
    • pp.22-28
    • /
    • 2012
  • For a methanol separation column of the BPA (Bisphenol A) plant, HAZOP (hazard and operability) assessment was performed and damage ranges were predicted from the accident scenarios for the fire and the explosion. As a result, the damage range of the jet fire was 20 m in the case of rupture of the discharge pipe (50 mm diameter) of safety valve, and that of the flash fire was 267 m in the case of catastrophic rupture. Also, the damage ranges of the unconfined vapor cloud explosion (UVCE) for the rupture of the discharge pipe and for the catastrophic rupture were 22 m and 542 m, respectively. For the worst case of release scenarios, safety measures were suggested as follows: the pressure instruments, which can detect abnormal rise of the internal pressure in the methanol separation column, should be installed by the 2 out of 3 voting method in the top section of the column. Through the detection, the instruments should simultaneously shut down the control and the emergency shut-off valves.

Development of a self-leveling system for the bucket of an agricultural front-end loader using an electro hydraulic proportional valve and a tilt sensor (전자유압 비례밸브와 경사센서를 이용한 농용 프론트 로더 버켓 능동수평유지 시스템 개발)

  • Lee, Chang Joo;Ha, Jong Woo;Choi, Deok Su;Kim, Hak Jin
    • Journal of Drive and Control
    • /
    • v.12 no.4
    • /
    • pp.60-70
    • /
    • 2015
  • A front-end loader (FEL) mounted on an agricultural tractor is one of the most commonly used implements for farm work. However, when the tractor carries material using the bucket attached to the FEL on a sloping ground, the materials can spill or roll back over the operator due to the tilted body, thereby requiring the bucket surface to remain level at a constant value regardless of varying slopes. In this study, an active system for controlling the angle of the FEL bucket on a tractor based on the real-time measurement of ground slopes was developed to enable the bucket to constantly remain level. A FEL simulator operated based on an electro hydraulic proportional valve (EHPV) was constructed in the laboratory to develop a proportional-integral-derivative (PID) controller forming a virtual electronic control unit (ECU) on the computer, which could automatically adjust the bucket angles depending on varying input angles while sending SAE-J1939 associated messages via CAN BUS to the EHPV. The different parameter values for the PID controller due to the gravity effect of the bucket were determined using a manual PID tuning method while assuming that the tractor travels on either an ascending slope or a descending slope. The developed PID control-based self-leveling system showed a mean of steady-state errors of within $1^{\circ}$ and a mean of delayed times of ~ 0.8s when the step input of $+20^{\circ}$ was given, implying that the developed system and control algorithm would be effective in maintaining the bucket angle at a certain value. Future studies include the improvement of the control algorithm to reduce such a time delay as well as the application of the developed algorithm to the FEL mounted on a tractor tested at a testing ground.