HYDRAULIC ACTIVE GUIDE ROLLER SYSTEM FOR HIGH-SPEED ELEVATOR BASED ON FUZZY CONTROLLER

Increase of elevator speed brings about amplified vibrations of high-speed elevator. In order to reduce the horizontal vibrations of high-speed elevator, a new type of hydraulic active guide roller system based on fuzzy logic controller is developed. First the working principle of the hydraulic guide system is introduced, then the dynamic model of the horizontal vibrations for elevator cage with active guide roller system and the mathematical model of the hydraulic system are given. A fuzzy logic controller for the hydraulic system is designed to control the hydraulic actuator. To improve the control performance, preview compensation for the controller is provided. Finally, simulation and experiments are executed to verify the hydraulic active guide roller system and the control strategy. Both the simulation and experimental results indicate that the hydraulic active guide roller system can reduce the horizontal vibrations of the elevator effectively and has better effects than the passive one, and the fuzzy logic controller with preview compensation can give superior control performance.

Roller Screw and Threaded Chain Speed Reducer: An Experimental Evaluation

We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuration lessens wear, increases load capacity, and improves efficiency. The threaded chain consists of nut-shaped links. This paper presents the results of tests carried out on a prototype with a reduction ratio of 46.

Analysis of Dynamic Characteristics of Forced and Free Vibrations of Mill Roll System Based on Fractional Order Theory

In this paper,the main researches are focused on the horizontal nonlinear vibration characteristics of roll systems for rolling mill,mainly including the study of forced vibration and free vibration of the roller.Firstly,the nonlinear damping parameters and nonlinear stiffness parameters within interface of the rolling mill are both considered,and a fractional-order differential term is also introduced to model the horizontal nonlinear vibration.Secondly,the averaging method is introduced to solve the forced vibration system of the mill roll system,and the amplitude-frequency characteristic curves of the system are obtained for different orders,external excitation amplitudes,stiffness and fractional order coefficients.Thirdly,the amplitude-frequency and phasefrequency characteristics of the free vibration of the mill roll system are investigated at different fractional orders.Then,the accuracy of the averaging method for solving the dynamic characteristics of the system is verified by numerical analysis,and the effect of the fractional differential term coefficients and order on the dynamic characteristics of the roll system are investigated.Finally,the time-frequency characteristics and phase-frequency characteristics of free vibration systems at different fractional orders are studied.The validity of the theoretical study is also verified through experiments.

Dynamic Modeling of a Roller Chain Drive System Considering the Flexibility of Input Shaft

Roller chain drives are widely used in various high-speed, high-load and power transmission applications, but their complex dynamic behavior is not well researched. Most studies were only focused on the analysis of the vibration of chain tight span, and in these models, many factors are neglected. In this paper, a mathematical model is developed to calculate the dynamic response of a roller chain drive working at constant or variable speed condition. In the model, the complete chain transmission with two sprockets and the necessary tight and slack spans is used. The effect of the flexibility of input shaft on dynamic response of the chain system is taken into account, as well as the elastic deformation in the chain, the inertial forces, the gravity and the torque on driven shaft. The nonlinear equations of movement are derived from using Lagrange equations and solved numerically. Given the center distance and the two initial position angles of teeth on driving and driven sprockets corresponding to the first seating roller on each side of the tight span, dynamics of any roller chain drive with two sprockets and two spans can be analyzed by the procedure. Finally, a numerical example is given and the validity of the procedure developed is demonstrated by analyzing the dynamic behavior of a typical roller chain drive. The model can well simulate the transverse and longitudinal vibration of the chain spans and the torsional vibration of the sprockets. This study can provide an effective method for the analysis of the dynamic characteristics of all the chain drive systems.

DYNAMIC RESPONSE OF ROLLER GEAR INDEXING CAM SYSTEM CONSIDERING CLEARANCE AND MOTOR CHARACTERISTIC

The dynamic responses of roller gear indexing cam mechanism are investigated .With applying Lagarange equation and Gear method,motion equations of this mechanism including clearance,motor characteristic,torsion flexibility are developed and solved.The results show that clearance affects primarily the response on turret,and has little effects on the responses on rotary table.At the same time,the velocity fluctuation of motor shaft is not serious for the existence of inertia of reducer,and the high frequency of velocity fluctuation of camshaft is related with the torsion stiffness of shaft and the clearance between pairs.

Design and Kinematic Analysis of a Driving Roller-type No-till Seeding and Hole-forming System

Conventional no-till seeders should cut or remove crop straw and residue,when in operation and thus present a number of problems,including high performance requirements for the cutting component,high power consumption,dust raising and interference from intertwined straw.In view of this,in this study,a driving roller dibbling-type no-till seeding and hole-forming(DGR-NT-SHF)system was designed to be capable of penetrating soil and creating holes without requiring any special preparation of the surface covering.The core mechanism of this system consisted of a land wheel-driven driving roller and a duckbill-type roller seeder,which were internally tangent to one another.The rotating roller rolled the straw into a thin layer,and the duckbills extended from the roller and penetrated this thin layer of straw and subsequently formed the holes and planted the seeds.Based on kinematic analysis,a mathematical model was established to depict the relations between the rear angle of the duckbill(α),the front angle of the duckbill(β),the angular velocity of the duckbill-type roller seeder(ω0),the angular velocity of the roller(ω1),and the aperture of the duckbill outlet on the roller(θ).In contrast to a driven roller-type no-till seeding and hole-forming DNR-NT-SHF system,several parameters of the DGR-NT-SHF system were established for planting seeds at a plant spacing that was an integral multiple of 100 mm:the radius of the duckbill-type roller seeder,200 mm;radius of the roller,400 mm;α,23°;andβ,5°.Based on the analysis of the models using the MATLAB Image Processing Module with a relation betweenω1 and the number of outlets on the roller as the constraint,the optimal number of outlets on the roller and theω1/ω0 ratio were determined to be 21 and 4/7,respectively.Kinematic simulation on a digital prototype was performed using computer aided three-dimensional interactive application(CATIA)to observe the motion of the DGR-NT-SHF system,when the duckbills on the duckbill-type roller seeder were open and to determine the locations of the duckbills relative to the outlets.To ensure the duckbills could be successfully opened,the chord length of the outlets was ultimately determined to be 71 mm.The prototype test results showed that the DGR-NT-SHF system met the design requirements and that the operation was straightforward and reliable.In addition,compared to the DNR-NT-SHF system,the DGR-NT-SHF system performed better in penetration and exerted no impact on the duckbills,thus providing an effective technical option for no-till seeding.

Design and Implementation of PLC-Based Autonomous Construction System of Unmanned Vibratory Roller

The vibratory roller is a piece of vital construction machinery in the field of road construction.The unmanned vibratory roller efficiently utilizes the automated driving technology in the vehicle engineering field,which is innovative for the unmanned road construction.This paper develops and implements the autonomous construction system for the unmanned vibratory roller.Not only does the roller have the function of remote-controlled driving,but it also has the capability of autonomous road construction.The overall system design uses the Programmable Logic Controller(PLC)as the kernel controller.It establishes the communication network through multiple Input/Output(I/O)modules,Recommended Standard 232(RS232)serial port,Controller Area Network(CAN)bus,and wireless networks to control the roller vehicle completely.The locating information is obtained through the Global Navigation Satellite System(GNSS)satellite navigation equipment group to support the process of autonomous construction.According to the experimental results,the autonomous construction system can finally enable the roller to perform driving operations and construction independently,which was a significant step forward in engineering application.

Optimal Design of Tapered Roller Bearings Based on Multi⁃Physics Objectives Using Evolutionary Algorithms

Rolling element bearing is the most common machine element in rotating machinery.An extended life is among the foremost imperative standards in the optimal design of rolling element bearings,which confide on the fatigue failure,wear,and thermal conditions of bearings.To fill the gap,in the current work,all three objectives of a tapered roller bearing have been innovatively considered respectively,which are the dynamic capacity,elasto-hydrodynamic lubrication(EHL)minimum film⁃thickness,and maximum bearing temperature.These objective function formulations are presented,associated design variables are identified,and constraints are discussed.To solve complex non⁃linear constrained optimization formulations,a best⁃practice design procedure was investigated using the Artificial Bee Colony(ABC)algorithms.A sensitivity analysis of several geometric design variables was conducted to observe the difference in all three objectives.An excellent enhancement was found in the bearing designs that have been optimized as compared with bearing standards and previously published works.The present study will definitely add to the present experience based design followed in bearing industries to save time and obtain assessment of bearing performance before manufacturing.To verify the improvement,an experimental investigation is worthwhile conducting.

Discussion on Lightning Protection Design of "Feilongzaitian" Roller Coaster of Fangte in Zigong

The lightning protection design of "Feilongzaitian" roller coaster of Fangte in Zigong was discussed, and the lightning protection measures of "Feilongzaitian" roller coaster were analyzed from the aspects of direct lightning protection, grounding and lightning electromagnetic impulse protection.

Analysis of Vibrations of Roller of the Polymer Composite Coating Equipment on Stitches of Tarpaulin Materials

The article presents a structural diagram and the principle of operation of the installation of a sewing machine for applying a polymer composition to the stitch lines of tarpaulin materials. The calculation schemes and the mathematical model of oscillations of the axis of the composite roller during the application of the polymer composition along the lines of tarpaulin materials are presented. Based on the numerical solution of the problem, the regularities of roller oscillations are presented. The main parameters of the system are substantiated.

Roller转子密炼机聚合物流体的混沌混合特性

建立了Roller转子密炼机二维有限元模型,利用网格重叠技术,对密炼机流体的流动过程进行了数值模拟。利用粒子示踪技术,采用4阶Runge-Kutta法计算了不同转数和不同流体粒子释放位置的密炼机Poincaré截面、平均对数线拉伸及Lyapunov指数等混沌混合参数。从非线性混沌理论的视角研究了Roller转子密炼机的混沌混合机理。结果表明,在双转子周期性扰动的作用下,聚合物流体在密炼机内被反复地拉伸、折叠,且啮合区的Poincaré截面出现了典型的"马蹄形"混沌结构。随着混合周期的增加,平均线拉伸以指数形式增长,且Lyapunov指数大于零。Roller转子密炼机流体具有混沌对流的特征。

Young Chinese Baker Rocks “Bread Olympics”

A young Chinese baker became a world champion by pursuing his passion and working hard to overcome challenges.Adancing lion,giant panda,roller coaster,and a merry-go-round in eye-popping shapes-when these elements are grouped together,what kind of magic can happen?Winning magic if you are Gong Xin,a Gen Z baker from China who made a one-meter-high artistic creation using all of these elements.He won the ninth World Bread Competition(Mondial du Pain)as a result.Many Chinese found it hard to believe what he had done after seeing pictures.“This is virtually a work of art,”and“it is equivalent to a foreigner taking first place in a dumpling-making contest in China,”were some of the many online comments.As the host of the competition,France,famous for its bread-making techniques,was beaten into second place,leaving the French media shocked that a Chinese baker had won the famous world bread contest.

国际化发展进程中辊压机控制系统的优化

辊压机运行过程中,常采用“恒压力”或“恒辊缝”的控制模式,两种控制模式各有利弊。在某原料粉磨系统技改项目中,完成了两种控制系统程序语言的统一,首次实现了可在线一键切换的“恒压力”或“恒辊缝”双控制模式。对比分析了该项目在不同控制模式下的系统产量、电耗、出辊压机物料筛分数据及经济效益。分析表明,在单一的控制模式下,辊压机运行可能存在有用功问题,采用双控制系统可适应不同条件下的生产需求。同时,开发了可视化辊压机运行保护及巡检提示程序,提高了水泥工厂(尤其是国外技术能力弱的辊压机用户)对辊压机巡检维护的及时性和全面性。

Monforts to debut the coaTTex at Techtextil 2024

At the Techtextil show for technical textiles which take place in Frankfurt from April 23-25,Monforts launched its new coaTTex coating unit exclusively dedicated to air knife and knife-over-roller coating.For single-sided application with paste or foam,the versatile coaTTex is suitable for both incorporation into existing finishing ranges as well as installation with new Monforts lines,notably the industry-leading Montex stenter systems.

Banbury和Roller转子密炼机局部和全局混合特性

采用有限元法,利用Polyflow软件计算了Banbury和Roller两种转子密炼机检测线的速度、剪切速率和混合指数分布,对比分析了两种转子的局部混合特性。通过计算停留时间分布、对数拉伸率、平均混合效率和粒子束分布指数等混合参数,对比分析了两种转子密炼机的全局混合特性。在此基础上,研究了具有典型运动规律流体粒子的动力学特性,分析了密炼机流体的位移和速度突变产生的受力和混合突变特征,为深入理解密炼机流体的复杂混合机理提供了一定的理论参考。

智能压实控制系统在穆棱市奋斗水库工程中的应用

奋斗水库项目是国务院确定的172个重点水利项目之一,是黑龙江省第一座碾压混凝土重力坝。传统的碾压混凝土施工主要靠机手的操作经验,容易出现漏压、过压的情况,传统的检测方法采用抽检方式,属于事后控制,存在费时、费工、抽检点密度小、检测结果不能真实反映整个施工作业面的压实度的实际情况。奋斗水库工程大坝碾压混凝土施工过程中采用了智能压实控制系统进行辅助质量管理,依靠智能化、信息化的连续监测技术,实时显示并记录整个碾压过程,有效控制大坝碾压混凝土施工质量。

轮轨冲击对提速客车轴箱轴承系统的影响分析

将铁路车轮踏面扁疤运动模型模拟得到的冲击载荷引入双列圆柱滚子轴承轴箱系统力矩平衡模型,数值分析不同扁疤参数在铁路运行工况下导致的轴箱中组配的圆柱滚子轴承内部接触变形、偏转与局部极限接触应力的影响,进而评估轴箱中组配的圆柱滚子轴承系统的接触疲劳损坏与轮轨冲击接触的相关性,建议扁疤长度控制在40 mm以内。

数据中心冷却系统制冷剂泵滚滑转子型线理论及性能研究

为了解决数据中心冷却系统制冷剂泵中转子的磨损问题,设计一种新型滚滑转子型线,利用滚柱与内转子和外转子进行啮合,形成一种滚动形式的内啮合转子泵,研究滚滑转子型线的构建,推导制冷剂泵排量公式;分析滚柱半径、包角和偏心距的变化对滚滑转子几何结构、制冷剂泵排量、滚滑转子承受应力的影响。结果表明,随着滚柱半径的增大,制冷剂泵的排量略微减小,滚滑转子受到的最大应力先减小后增大;随着包角的增大,滚滑转子受到的最大应力逐渐增大;随着偏心距的增大,制冷剂泵的排量逐渐增大,但滚滑转子受到的最大应力逐渐增大。

带式输送机结构优化及智能自动布料技术研究

为提高矿山粉碎作业机械化自动化程度,进行带式输送机结构优化及自动布料技术研究。实际应用中,预选筛分矿仓容积有限,布料小车需频繁移动,但结构设计上的缺陷,容易造成行走小车齿轮损坏、机架变形、啃轨等问题。为解决以上问题,进行分料小车结构加固、轨道和轮子选型更换、驱动装置变频改造等结构优化。此外,为实现输送机自动布料降低工人劳动强度,提出自动布料技术方案。通过实施结构优化及智能自动布料技术方案,提高了破碎系统的稳定性及寿命,减少人力成本,经济效益显著。

生料辊压机终粉磨系统节能减碳实践中存在的问题与对策

因原材料水分大、系统烘干能力不足、设备阻力大、高效选粉机结构缺陷等原因造成生料辊压机终粉磨系统运行不稳定且循环负荷大、停机次数较多、系统阻力大、循环风机拉风过大、细度跑粗现象,导致生料工段电耗偏高、成品细度合格率低。对物料特性、工艺流程、设备选型及运行、成品细度进行热工诊断和研究分析,并实施相应的设备、工艺及系统操作优化措施。优化后,生料辊压机终粉磨系统工段电耗降低了2.2kWh/t,选粉效率提升,成品细度明显改善,实现提质增效,节能减碳的目的。