A double-magnetic-source magnetic circuit with pole shoes for an electromagnetic angular vibration exciter

2017 ◽  
Vol 54 (4) ◽  
pp. 461-470 ◽  
Author(s):  
Bo Tang ◽  
Wen He ◽  
Shushi Jia
Keyword(s):  
Magnetic Circuit ◽  
Vibration Exciter ◽  
Magnetic Source ◽  
Angular Vibration

scholarly journals A new magnetorheological elastomer torsional vibration absorber: structural design and performance test

2021 ◽  
Vol 12 (1) ◽  
pp. 321-332
Author(s):  
Pu Gao ◽  
Hui Liu ◽  
Changle Xiang ◽  
Pengfei Yan ◽  
Taha Mahmoud
Keyword(s):  
Magnetic Field ◽  
Torsional Vibration ◽  
Performance Test ◽  
Magnetic Circuit ◽  
Circuit Simulation ◽  
Variable Stiffness ◽  
Vibration Absorber ◽  
Vibration Exciter ◽  
Magnetorheological Elastomer ◽  
The Magnetic Field

Abstract. The semi-active torsional vibration absorber can effectively reduce the torsional vibration of the power-train system. In this paper, a new type of variable stiffness torsional vibration absorber with a magnetorheological elastomer (MRE) as an intelligent controlling element is designed, and the modal analysis, frequency-tracking scheme, and damping effects have been studied. A transient dynamic simulation is utilized to validate the rationality of the mechanical structure, the magnetic field parameters of the absorber are matched, and the magnetic circuit simulation analysis and the magnetic field supply analysis are carried out to verify the closed magnetic circuit. The principle prototype of the innovative vibration absorber is manufactured, the magnetic field strength of the absorber is tested by a Gauss meter, and the results show the efficacy of magnetizing the vibration absorber with a conductive slip ring by solving the magnetizing problem of the rotating parts of the vibration absorber. A special-purpose test rig with a torsional vibration exciter as a power source has been implemented. A comparative experiment has been carried out to test the frequency shift characteristics and authenticate the vibration-reduction effect of the new MRE torsional vibration absorber.

scholarly journals Rectangular Closed Double Magnetic Circuit Offering Ultra-Long Stroke for Ultra-Low-Frequency Vibration Exciter

2020 ◽  
Vol 10 (17) ◽  
pp. 6118
Author(s):  
Junning Cui ◽  
Wei Li ◽  
Xingyuan Bian ◽  
Zhangqiang He ◽  
Limin Zou
Keyword(s):  
High Performance ◽  
Magnetic Circuit ◽  
Harmonic Distortion ◽  
Low Frequency ◽  
Fem Analysis ◽  
Magnetic Flux Density ◽  
Vibration Exciter ◽  
Low Frequency Vibration ◽  
Lumped Parameter ◽  
Long Stroke

High-performance magnetic circuit offering uniform magnetic flux density (MFD) along ultra-long stroke is the key to develop a vibration exciter for ultra-low-frequency (ULF) vibration calibration. In this paper, a rectangular closed double magnetic circuit (RCDMC) offering ultra-long stroke up to 1.2 m is modeled and optimized. In order to overcome the modeling difficulty arising from the long stroke, a high-accuracy theoretical model is established taking advantage of the structural symmetry of the RCDMC through lumped parameter magnetic equivalent circuit method. Matrix equations are derived based on Kirchhoff’s law and solved by iteration calculation to deal with the strong nonlinear characteristics of the yoke material. The deviations between the model and finite element method (FEM) analysis results are less than 1% for non-saturated yokes and ~10% for saturated yokes. Theoretically, an MFD up to 122 mT and an acceleration waveform harmonic distortion (AWHD) as low as 0.45% are achieved through model-based optimization. Experiments are carried out using an RCDMC prototype assembled in a horizontal vibration exciter. The experimental results show that an MFD of 102 mT and an AWHD of 0.27% along 1.2 m stroke are achieved, making the proposed RCDMC a solution for ULF vibration exciter.

Closed-Double-Magnetic Circuit for a Long-Stroke Horizontal Electromagnetic Vibration Exciter

2013 ◽  
Vol 49 (8) ◽  
pp. 4865-4872 ◽  
Author(s):  
Wen He ◽  
Chunyu Wang ◽  
Mei Yu ◽  
Runjie Shen ◽  
Shushi Jia
Keyword(s):  
Magnetic Circuit ◽  
Vibration Exciter ◽  
Electromagnetic Vibration ◽  
Long Stroke

Effects of contact gap on nondestructive evaluation using magnetic measurement for ferromagnetic steel

2020 ◽  
Vol 64 (1-4) ◽  
pp. 969-975
Author(s):  
Hiroaki Kikuchi ◽  
Yuki Sato
Keyword(s):  
Magnetic Flux ◽  
Nondestructive Evaluation ◽  
Effective Permeability ◽  
Magnetic Circuit ◽  
Magnetic Measurement ◽  
Air Gap ◽  
Motive Force ◽  
Hysteresis Curve ◽  
Evaluation Technique ◽  
Ferromagnetic Steel

We investigated effects of contact gap on magnetic nondestructive evaluation technique using a magnetic single-yoke probe. Firstly, we evaluated hysteresis curves and impedance related to permeability of the material measured by a single-yoke probe, when an air gap length between the probe and specimens changes. The hysteresis curve gradually inclines to the axis of the magneto-motive force and magneto-motive force at which the magnetic flux is 0 decreases with increasing the gap length. The effective permeability also decreases with increasing the gap thickness. The incremental of gap thickness increases the reluctance inside the magnetic circuit composed of the yoke, specimen and gap, which results in the reduction of flux applying to specimen.

Analysis of magnetic force and dynamic characteristic for non-contact permanent magnet linear drive device

2020 ◽  
Vol 64 (1-4) ◽  
pp. 1337-1345
Author(s):  
Chuan Zhao ◽  
Feng Sun ◽  
Junjie Jin ◽  
Mingwei Bo ◽  
Fangchao Xu ◽  
...  
Keyword(s):  
Finite Element ◽  
Permanent Magnet ◽  
Dynamic Characteristic ◽  
Driving Force ◽  
Magnetic Circuit ◽  
Response Speed ◽  
Computation Method ◽  
Element Analysis ◽  
Element Simulation ◽  
The Relationship

This paper proposes a computation method using the equivalent magnetic circuit to analyze the driving force for the non-contact permanent magnet linear drive system. In this device, the magnetic driving force is related to the rotation angle of driving wheels. The relationship is verified by finite element analysis and measuring experiments. The result of finite element simulation is in good agreement with the model established by the equivalent magnetic circuit. Then experiments of displacement control are carried out to test the dynamic characteristic of this system. The controller of the system adopts the combination control of displacement and angle. The results indicate that the system has good performance in steady-state error and response speed, while the maximum overshoot needs to be reduced.

A Resonant Electromagnetic Vibration Exciter of Oscillations with a Feedback

Vestnik MEI ◽  
2020 ◽  
Vol 1 (1) ◽  
pp. 62-66
Author(s):  
Mukhtorkhan Ibadullaev ◽  
◽  
Almikhan K. Nuraliev ◽  
Azamat Zh. Esenbekov ◽  
Alisher Zh. Nazarov ◽  
...  
Keyword(s):  
Vibration Exciter ◽  
Electromagnetic Vibration

CARPENTER 430FR SOLENOID QUALITY

Alloy Digest ◽  
1977 ◽  
Vol 26 (3) ◽  
Keyword(s):  
Stainless Steel ◽  
Electrical Resistivity ◽  
Magnetic Circuit ◽  
Iron Alloy ◽  
Heat Treating ◽  
Solenoid Valve ◽  
Magnetic Flux Density ◽  
Magnetic Components ◽  
Electromagnetic Relay ◽  
Core Components

Abstract Carpenter 430FR Solenoid Quality stainless steel is a ferritic chromium-iron alloy developed especially for A.C. and D.C. magnetic circuit applications such as solenoid valve core components and electromagnetic relay cores. The electrical resistivity of 430FR is approximately 25% higher than other commercially available 430F stainless. Increased electrical resistivity provides better performance of magnetic components, particularly at power frequencies and high magnetic flux density. This datasheet provides information on composition, physical properties, and hardness. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SS-337. Producer or source: Carpenter.

Accuracy of diffusion tensor magnetic resonance imaging tractography assessed using intraoperative subcortical stimulation mapping and magnetic source imaging

2007 ◽  
Vol 107 (3) ◽  
pp. 488-494 ◽  
Author(s):  
Jeffrey I. Berman ◽  
Mitchel S. Berger ◽  
Sungwon Chung ◽  
Srikantan S. Nagarajan ◽  
Roland G. Henry
Keyword(s):  
White Matter ◽  
Magnetic Resonance ◽  
Diffusion Tensor ◽  
Fiber Tracking ◽  
Bipolar Electrode ◽  
Source Imaging ◽  
Magnetic Source Imaging ◽  
Motor Pathway ◽  
Magnetic Source ◽  
Subcortical Stimulation

Object Resecting brain tumors involves the risk of damaging the descending motor pathway. Diffusion tensor (DT)–imaged fiber tracking is a noninvasive magnetic resonance (MR) technique that can delineate the subcortical course of the motor pathway. The goal of this study was to use intraoperative subcortical stimulation mapping of the motor tract and magnetic source imaging to validate the utility of DT-imaged fiber tracking as a tool for presurgical planning. Methods Diffusion tensor-imaged fiber tracks of the motor tract were generated preoperatively in nine patients with gliomas. A mask of the resultant fiber tracks was overlaid on high-resolution T1- and T2-weighted anatomical MR images and used for stereotactic surgical navigation. Magnetic source imaging was performed in seven of the patients to identify functional somatosensory cortices. During resection, subcortical stimulation mapping of the motor pathway was performed within the white matter using a bipolar electrode. Results A total of 16 subcortical motor stimulations were stereotactically identified in nine patients. The mean distance between the stimulation sites and the DT-imaged fiber tracks was 8.7 ±3.1 mm (±standard deviation). The measured distance between subcortical stimulation sites and DT-imaged fiber tracks combines tracking technique errors and all errors encountered with stereotactic navigation. Conclusions Fiber tracks delineated using DT imaging can be used to identify the motor tract in deep white matter and define a safety margin around the tract.

Sign in / Sign up

Export Citation Format

Share Document