Hydraulic cylinder

Tato bakalářská práce se zabývá hydromotory a jejich rozdělením. Dále se věnuje přímočarým hydromotorům, jejich rozdělení, částem, ze kterých se skládá, a také jejich využitím. Důležitou součástí hydromotorů jsou také pevnostní výpočty, které jsou v práci také uvedeny. Práce obsahuje matematický model pro výpočet vlastních frekvencí přímočarých hydromotorů.This bachelor thesis deals with the hydraulic motors and their distribution. It also deals linear hydraulic motors, their distribution, parts of which are composed, and their use. An important part of the hydraulic motors are strength analysis, which are also listed in this thesis. The bachelor thesis includes a mathematical model for natural frequuencies solution of linear hydraulic motors.

Vibration dampener for Niles vertical boring mill ram

Controlled hydraulic cylinder, which serves as a vibration dampener, is used as a ram support unit. Constant pressure is exerted, minimizing the cutting tool vibration

THE INFLUENCE OF THE STIFFNESS COEFFICIENT OF THE HYDRAULIC LIQUID ON THE DYNAMICAL BEHAVIOUR OF THE SYSTEM “HYDRAULIC CYLINDER – LOAD”

In this paper we suggest a way how to determine the stiffness coefficient of the hydraulic liquid in a hydraulic cylinder under load and we also show its influence on the dynamical properties and behavior of the system “hydraulic cylinder– load”.In this paper we suggest a way how to determine the stiffness coefficient of the hydraulic liquid in a hydraulic cylinder under load and we also show its influence on the dynamical properties and behavior of the system “hydraulic cylinder– load”

Rozšířený analytický model hydraulického válce s respektováním rozdílných činných ploch pístnice a objemů

Standard analytic linear model of hydraulic cylinder usually comes from assumptions of identical action piston areas on both sides of hydraulic cylinder (double piston rod) and suitable operation point, which is usually chosen in the middle of piston. By reason of that volumes inside of cylinder are than same. Moreover for control of that arrangement of hydraulic cylinder, usually controlled by 4/3 servovalve, the same mount of flows comes in and comes out to each of chambers of hydraulic cylinder. Presented paper deal with development of extended form of analytic linear model of single piston rod hydraulic cylinder which respects different action piston areas and volumes inside of chambers of hydraulic cylinder and also two different input flows of hydraulic cylinder. In extended model are also considered possibilities of different dead volumes in hoses and intake parts of hydraulic cylinder. Dead volume has impact on damping of hydraulic cylinder.Standardní analytický lineární model hydraulického válce obvykle vychází z předpokladu shodných činných ploch na obou stranách pístnice (oboustranná pístnice) a vhodného pracovního bodu, který je obvykle volen uprostřed pístnice. Z toho důvodu jsou pak objemy uvnitř jednotlivých komor hydraulického válce stejné. Mimoto pro řízení takovéhoto uspořádávání hydraulického válce, obvykle řízeného čtyřcestným, třístavovým servoventilem 4/3 přitékají a odtékají stejná množství průtoků do každé z komor válce. Presentovaný příspěvek se zabývá vývojem rozšířené formy analytického lineárního modelu hydraulického válce s jednostrannou pístnicí, který respektuje rozdílné činné plochy na pístnici a rozdílné objemy uvnitř komor hydraulického válce a rovněž také umožňuje uvažovat oba dva vstupy průtoků do hydraulického válce. V rozšířeném modelu jsou rovněž uvažovány možnosti různých mrtvých objemů v hadicích a přívodních částech hydraulického válce. Mrtvý objem má velký vliv na tlumení hydromotoru

Design, Fatigue, and Strength Analysis of a Tie Rod Hydraulic Cylinder Bolt

This report illustrates strength and fatigue analysis completed on a tie rod hydraulic cylinder bolt from a Lion TX 2500 tie rod hydraulic cylinder. The goal was to: solve for total clamping force, damping force per bolt at 90% proof load strength, amount of force per bolt, find the required number of bolts to hold the hydraulic cylinder together, solve for bolt spacing requirements, estimate a safety factor based on proof load strength, nut shear strength, required nut thickness, the least number of threads that must be engaged, estimate R.R. Moore Bending Fatigue Strengths, estimate the maximum value of P that will not cause eventual fatigue failure, and estimate a safety factor with respect to eventual bolt fatigue failure. Calculations show that the hydraulic cylinder must be built using four 0.5 in bolts with a minimum of nine threads engaged. The hydraulic cylinder is capable of supporting a constant load of 22,704 lb without eventual fatigue failure. Safety factors were calculated based on proof load strength with respect to eventual bolt fatigue failure to be 4.11 and 2, respectively. This analysis validated the manufacturer’s design and specifications of the hydraulic cylinder

Design and simulation analysis of an improved wearable power knee exoskeleton

The wearable lower limb power robotic exoskeleton is a device that can improve the human walking ability. In this paper, an improved exoskeleton device for knee joint is designed, including the improvement of mechanical structure and hydraulic cylinder. In order to verify the effectiveness of the improvement of the hydraulic cylinder, we have carried out the following studies. Firstly, in terms of mechanical structure, length adjusting device is added to meet the needs of different people. At the same time, a limit device is added to the knee joint to improve the safety performance and comfort. Secondly, the dynamics of the model is carried out by Lagrange, and the exoskeleton model is established for ADAMS motion simulation. The force of ADAMS simulation, the calculated by Lagrange equation and the force of the first edition of hydraulic cylinder are compared, and the force selection of hydraulic cylinder is analyzed. By comparison with the first edition, the optimization rate of the improved hydraulic cylinder reaches 8 %. Finally, in order to verify the rationality of ADAMS simulation and the effectiveness of hydraulic cylinder improvement, the wear test is carried out, the average errors of leg centroid in normal walking, wearing exoskeleton walking and ADAMS simulation data are compared. The average error rate is less than 10 %. The results show that the simulation model design is reasonable, and the effectiveness of the hydraulic cylinder improvement is verified. The exoskeleton device designed can well follow the human motion. The simulation analysis of the exoskeleton provides important parameters for the manufacture and it also provides theoretical basis for the later control theory

Tilt table for ergometers and other biomedical devices

Table adjusts to any position between horizontal and vertical. Apparatus includes - floor plate, plate hinged to floor plate, for carrying ergometer, hydraulic cylinder and piston on plate sides, linking them, hydraulic system, positive stops, padded backrest and headrest, one hand controls, and constraint system

Prototipe double acting cylinder transparan sebagai media pembelajaran sistem hidrolik

Double acting cylinders in its application are widely used in the industry and are often applied in maintenance or repair instruments. The purpose of this research is to design and make a double acting cylinder so that the movement of the hydraulic cylinder its fluid flow can be seen clearly and easily implemented in the movement process, especially in the learning process. The research employs experimental method by directly design a transparent double acting cylinder. This transparent double acting cylinder will later be applied to the hydraulic trainer. The steps taken were determining the transparent material, making material samples for tensile tests, designing and making hydraulic cylinders, conducting hydraulic cylinder tests using Autodesk Inventor 2019. From the test results of hydraulic cylinders made from acrylic using Autodesk Inventor 2019, the minimum pressure that occurs is 1,456 MPa and the maximum pressure that occurs is 6,573 MPa, in operation, the recommended pressure 1,456 to 5,551 MPa, double acting transparent cylinder which has a transparent hydraulic cylinder length of 250 mm, thickness 11.4 mm, hydraulic cylinder inner diameter 32 mm, hydraulic cylinder locking uses 4 bolts with size M8, design pressure 23 kg/cm².Keywords: hydraulic system, double acting cylinder, transparent

Гідропневматичний амортизатор підвіски транспортного засобу

Гідропневматичний амортизатор містить робочий гідроциліндр. В порожнині робочого гідроциліндра встановлено робочий поршень, з'єднаний зі штоком. Робочий поршень містить в собі пружний елемент. На днищі безштокової порожнини робочого гідроциліндра розташований додатковий пружний елемент. Гідрогазовий акумулятор з'єднаний з безштоковою порожниною робочого гідроциліндра через щонайменше два крізні отвори. Із зовнішньої сторони робочого гідроциліндра, в зоні розташування крізних отворів, встановлений клапан стиску з впускним клапаном. Крім того, із зовнішньої сторони робочого гідроциліндра штокова порожнина з'єднана з безштоковою порожниною за допомогою щонайменше двох трубопроводів, один з яких містить перепускний клапан, а другий - клапан віддачі. Кришка гідропневматичного амортизатора виконана з порожниною, яка заповнена мастилом. Таке виконання забезпечує експлуатаційну надійність гідропневматичного амортизатора та плавність і стійкість руху транспортного засобу. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/11039Hydropneumatic shock absorber contains working hydraulic cylinder. In the cavity of working hydraulic cylinder working piston is installed, it is connected with the stock. Working piston includes elastic element. Additional elastic element is located on the bottom of the rod-free cavity of working hydraulic cylinder. Hydropneumatic storage battery is connected with the rod-free cavity of the working hydraulic cylinder through at least two open-end holes. From the outer side of working hydraulic cylinder, in the area of location of open-end holes, the valve of compression with admission valve is installed. Furthermore, from the outer side of working hydraulic cylinder the rod cavity is connected with rod-free cavity with the help of at least two conduits, one of which contains bypass valve, and the second - valve of return. This embodiment ensures the operational reliability of hydropneumatic shock absorber and smoothness and durability of the motion of vehicle. При цитировании документа, используйте ссылку http://essuir.sumdu.edu.ua/handle/123456789/1103

Digital closed loop controller of hydraulic cylinder using linear transducer / Mohd. Aizuddin Khalid

Hydraulic power plays leading role in many heavy duty industry applications. However, the open controlling scheme is most widely used in hydraulic power system. Therefore, this study present the implementation of linear transducer for purpose of implementing a closed-loop controlling scheme for a linear hydraulic cylinder. For the development of closed-loop digital controller several components were used; personal computer, data acquisition board (Quanser-MPCIQ8), linear transducer and linear hydraulic cylinder. The personal computer is for generating the outputs/inputs signals, from MATLAB/SIMULINK software package, to the data acquisition board. SIMULINK is integrated with MATLAB, providing immediate access to an extensive range of tools that can develop algorithms, analyze and visualize simulations, customize the modeling environment, define signal, parameter, and test data. A data acquisition board is multipurpose board used to connect computer with outside environment. It contains of Digital Analog Converter (DAC) and Analog Digital Converter ADC). Receiving the digital signals from the computer and convert them to analog signals and via versa. Linear transducer provides highly accurate and reliable position control signals. It also can convert mechanical motion into electrical signals with high accuracy and precision. This linear transducer need to calibrate with MATLAB/SIMULINK in order to detect the signals. A calibration was done manually by using oscilloscope and compares the result with signal that provide to MATLAB/SIMULINK. Hydraulic cylinder produces linear motion and force by using pressurized hydraulic fluid. Hydraulic cylinders are able to work at a very high force with a relatively small supply of highly pressurized fluid. Hydraulic cylinder and linear transducer will attach together in order to give the feedback to MATLAB/SIMULINK. Feedback signal will show the displacement of hydraulic cylinder when it retracts or extract. The fabrication of base to attach the sensor wit hydraulic cylinder was done using traditional machining. The calibrations on this linear sensor have been carried out by using MATLAB and oscilloscope. The objective of the study was achieved by implementing the linear transducer sensor a closed-loop controller in linear hydraulic cylinder