scholarly journals Investigation on a No Trial Weight Spray Online Dynamic Balancer

2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Xialun Yun ◽  
Xuesong Mei ◽  
Gedong Jiang ◽  
Zhenbang Hu ◽  
Zunhao Zhang

In order to suppress the spindle vibration with high efficiency and high precision, a no without trial weight spray online balance method is proposed in this paper. By analyzing the relationship between the unbalanced excitation and the unbalanced response of the spindle, the relationship between the dynamic influence coefficient and the system model is studied. A high-speed spindle finite element analysis model was established, and the dynamic influence coefficient matrix was identified. A no trial weight spray online dynamic balancing system was developed, which has the advantages of without trial weight and high-precision loading. A new type of integrated balancing terminal that was formed using 3D printing technology was first proposed by our research group, and its advantages in various aspects are significantly higher than traditional assembly balanced terminals. The experimental verification of the without trial weight spray online dynamic balancing system was performed on a high-speed spindle test stand. Experiments show that the no trial weight spray online balancing method proposed in this paper can achieve high-efficiency and high-precision vibration suppression, greatly reducing balance time and cost of the spindle. At the same time, the online balance test also verified the reliability of the integrated balanced terminal.

Author(s):  
Qinfen Lu ◽  
Huanwen Li ◽  
Xiaoyan Huang ◽  
Yunyue Ye

Purpose – Due to the advantages of direct driven, high thrust density, and high efficiency, flux-switching linear motor (FSLM) is required for many applications, including aerospace and automotive. However, the vibration caused by detent force and difficulties in the assembly produced by the large normal force become the barriers that restrict its development. The paper aims to discuss these issues. Design/methodology/approach – In order to improve the electromagnetic performance of double-sided multi-tooth FSLM (DMTFSLM), a yokeless DMTFSLM with moving primary is proposed and compared with normal DMTFSLM. Moreover, with theoretical analysis, the selection principle of slot-pole number combination is obtained. DMTFSLMs with four slot/pole combinations, 6s/16p, 6s/17p, 6s/19p, 6s/20p, are analyzed based on finite element analysis model. Finally, several parameters of this yokeless DMTFSLM have been optimized to obtain the better performance. Findings – In yokeless DMTFSLM, it is found that the asymmetry of Back-EMF caused by the end-effect is eliminated, which leads to a better thrust force performance in comparison with the normal structure. The small attractive force between the secondary and the primary makes it easier for assembly and also can reduce the friction, which is more suitable for high-speed application. In addition, the best slot-pole combination rule is found through a simple theoretical analysis. Originality/value – The yokeless DMTFSLM has excellent electromagnetic performance, such as high thrust density, negligible normal force, and small force ripple. It is a strong candidate for high-precision device.


Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4407
Author(s):  
Mbika Muteba

There is a necessity to design a three-phase squirrel cage induction motor (SCIM) for high-speed applications with a larger air gap length in order to limit the distortion of air gap flux density, the thermal expansion of stator and rotor teeth, centrifugal forces, and the magnetic pull. To that effect, a larger air gap length lowers the power factor, efficiency, and torque density of a three-phase SCIM. This should inform motor design engineers to take special care during the design process of a three-phase SCIM by selecting an air gap length that will provide optimal performance. This paper presents an approach that would assist with the selection of an optimal air gap length (OAL) and optimal capacitive auxiliary stator winding (OCASW) configuration for a high torque per ampere (TPA) three-phase SCIM. A genetic algorithm (GA) assisted by finite element analysis (FEA) is used in the design process to determine the OAL and OCASW required to obtain a high torque per ampere without compromising the merit of achieving an excellent power factor and high efficiency for a three-phase SCIM. The performance of the optimized three-phase SCIM is compared to unoptimized machines. The results obtained from FEA are validated through experimental measurements. Owing to the penalty functions related to the value of objective and constraint functions introduced in the genetic algorithm model, both the FEA and experimental results provide evidence that an enhanced torque per ampere three-phase SCIM can be realized for a large OAL and OCASW with high efficiency and an excellent power factor in different working conditions.


Author(s):  
Rob P. Andrews

Abstract Vibration predictions for rotating machinery with high-speed flexible rotors must account for the methods and limitations of the balance test process which determine the residual rotor unbalance. Vibration predictions based on finite element analysis (FEA) methods are highly dependent upon the assumed rotor unbalance amplitude and phase. The actual residual unbalance distribution depends upon the measured influence coefficients and the least-mean-square (LMS) algorithm used to calculate balance correction weights. Repeatability of the vibration measurements is a key factor in successful balancing. The vibration predictions described in this paper use estimates of final residual unbalance obtained by simulating the balance test process. The simulation uses FEA based influence coefficients, a test based measurement uncertainty (repeatability) model, and LMS balance weight calculations including the specified vibration target levels. The simulations can be used to predict the limit of balance performance of the machinery and to evaluate design options for impact on residual unbalance levels.


2012 ◽  
Vol 215-216 ◽  
pp. 895-898
Author(s):  
Jun Hong Guo ◽  
De Jun Ma ◽  
Wei Chen ◽  
Zhong Kang Song

Finite element analysis is undertaken to identify the extent of loading deformation of instrumented indentation equipment frame which is a main part in High-precision instrumented indentation tester developed and realized by our group. The working load enacted in the model is varied from 10N to 100N, and the increment load is 10N. By plotting and fitting data of inclination angle and working load, the relationship between frame inclination angle and working load is established. The function of this relationship is θ=0.000024*F. When the working load is up to the upper bound 100N, the inclination angle of frame reaches the maximum value 0.00241°.Load analysis of push rod shows that the percent error between measured load values and real indentation load values caused by maximum inclination angle is in 10-8order. The conclusion is thus derived that frame inclination has nearly no effects on load measurement precision. The research in this paper confirms that the design of frame belonging to High-precision instrumented indentation tester is appropriate.


Author(s):  
Seizo Uematsu ◽  
Masana Kato

Abstract Finish roll forming under the constant center distance by forced feed of tool can be conceived as a method of eliminating errors in conventional form rolling under constant loads. This method generates a high-precision tooth profile by low-speed form rolling when a high rigid screw or cam is used as loading parts. In this study, the high-speed rolling conditions of this method for necessary to be applied in practical situations are discussed. The following conclusions are obtained. When the following design data are given (module, number of teeth, addendum modification coefficient, prescribed design precision, and material characteristics), the accuracy of rolled gear can be predicted from the relationship between the required feed for the tool and the theoretically calculated plastic deformation on the tooth profile. These conclusions are verified experimentally. For example, the tooth accuracy of rolled gears with module 5 can improve from JIS class 3 to JIS class 0 or 1 when the load Fmax is 4 to 5kN and the pitch line velocity is 7 m/min.


2011 ◽  
Vol 52-54 ◽  
pp. 1206-1211 ◽  
Author(s):  
Huai Xing Wen ◽  
Mei Yan Wang

The thermal characteristics of the motorized spindle determines maching qualities and cutting capabilities, and is one of the important factors influencing the precision of the high speed NC machine tool. To improve the performance of the high speed machine tool, it is important to study the thermal characteristics of the motorized spindle. It had been studied in two ways: one is finite element analysis by Ansys software, in which the finite element analysis model was built. According to the actual working condition, the heat source and the heat transfer coefficient of every part are calculated. On this basis, the temperature field and temperature rises were gotten in Ansys software. The other way is temperature rises experiment on the motorized spindle test platform. The result was shown in the form of curve. These two ways shown the same result: the highest temperature rise appears in the area of electromotor, then followed by the rolling bearing .The result provides the necessary theory basis for optimizing the structure of the motorized spindle and establishes a basis for the research and application about the high speed spindle.


2009 ◽  
Vol 2009 (0) ◽  
pp. _636-1_-_636-4_
Author(s):  
Takashi FUJIMOTO ◽  
Takeshi NAKAHARA ◽  
Kazuhiro Tsuruta ◽  
Feng ying CAO

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