scholarly journals Structure optimization of a pipetting device to improve the insertion effect of tips

2021 ◽  
Vol 12 (1) ◽  
pp. 501-510
Author(s):  
Zeng Huang ◽  
Chenxue Wang ◽  
Qian Su ◽  
Zhiping Lian
Keyword(s):  
High Throughput ◽  
Structure Optimization ◽  
Ball Screw ◽  
Pass Rate ◽  
Test Results ◽  
Axial Deformation ◽  
Ansys Software ◽  
Assembly Mechanism ◽  
Stiffness Model ◽  
Ball Screw Drive

Abstract. In order to solve the problems of the failure of disposable tip insertion which happens in the pipetting process of most multi-station and high-throughput pipetting devices, this paper proposes a high-rigidity screw-type pipette shaft–disposable tip assembly mechanism with excellent auto-centering effects based on the principle of the ball screw drive. The stiffness model of the new pipetting device is established, and its stiffness and axial deformation are analyzed. This new mechanism was introduced to a multi-station and high-throughput pipetting workstation, and the process of pipetting disposable tips is simulated by ANSYS software. The analytical results show that the stiffness value of the new pipetting device is approximately 90 N/µm, and the amount of deformation of the z-axis manipulator is reduced by about 60 % compared to the original pipetting device. Finally, physical verification of the prototype was carried out in the work. The test results show that the new pipetting workstation can increase the tightening rate of the tips by approximately 12 % after optimization when 96 tips are inserted in a single press. In addition, the pass rate of the tightness test of the optimized pipetting workstation has increased by approximately 20 %.

Modeling of axial contact stiffness of a double-nut with preloads

2016 ◽  
Vol 232 (4) ◽  
pp. 629-638 ◽  
Author(s):  
Tiemin Li ◽  
Fuhua Li ◽  
Yao Jiang ◽  
Haitong Wang ◽  
Yunsong Du
Keyword(s):  
Theoretical Model ◽  
Axial Load ◽  
Contact Stiffness ◽  
Ball Screw ◽  
Axial Stiffness ◽  
Axial Deformation ◽  
Displacement Sensors ◽  
Ball Screw Drive ◽  
Improved Model ◽  
Ball Screw Drives

Ball screw drives are commonly used to provide linear motion in machine tools. And stiffness is one of the most important performance indexes. However, stiffness of nuts with different preloads is difficult to be calculated precisely because of complex structures. In order to improve the calculating accuracy, a new model is proposed with the consideration of geometry errors of grooves and balls based on the existing theoretical model. The influence of geometry errors on axial deformation of double-nut is analyzed and modeled. Meanwhile, a preload-adjustable ball screw drive is constructed on the basis of a modified double-nut mechanism. A novel loading mechanism is designed to apply axial load on the working table and test the force in real time. Two laser displacement sensors are adopted to test axial deformation of the double-nut. The axial stiffness of the double-nut is analyzed based on the axial load and the axial deformation. Stiffness simulations of the new improved model, the theoretical model, and the empirical model are also analyzed. The contrastive analysis shows that the experimental results agree much better with the axial stiffness calculated by the new improved model. This study provides a more accurate model to calculate the stiffness of the double-nut with preloads for preloaded ball screw drives.

Hoist Sheave Structure Optimization and Lightweight

2015 ◽  
Vol 741 ◽  
pp. 133-137
Author(s):  
Xian Zhao Jia ◽  
Yong Fei Wang
Keyword(s):  
Working Condition ◽  
Geometric Model ◽  
Structure Optimization ◽  
Element Model ◽  
Stiffened Plate ◽  
Optimal Result ◽  
Ansys Software ◽  
Table Analysis ◽  
3D Geometric Model ◽  
Relational Table

To ensure wheel body of the hoisting sheave strength and stability condition. For the purpose of wheel body lightweighting. There are two schemes to reduce body weight.Reduce the spokes at the same time increase the ring stiffened plate, and reduce the spokes at the same time change the spokes width and thickness.The wheel body was established based on Pro/E 3D geometric model. Import the mesh in the Workbench of ANSYS software for finite element model. Statics analysis to select the optimized scheme. Establish a hoisting sheave wheel body under the actual working condition of widening the width - deformation - wheel weight relational table. Analysis to lightweight at the same time ensure that stiffness of wheel,then it can obtaine the optimal result.

scholarly journals Unbalanced Vibration Identification of Tangential Threshing Cylinder Induced by Rice Threshing Process

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Zhong Tang ◽  
Haotian Zhang ◽  
Yuepeng Zhou
Keyword(s):  
Service Life ◽  
Vibration Amplitude ◽  
Rotation Speed ◽  
Resonance Phenomenon ◽  
Test Results ◽  
Axial Vibration ◽  
Ansys Software ◽  
Cylinder Axis ◽  
Vibration State ◽  
Rice Stalks

Unbalanced vibration of tangential threshing cylinder increased the grain loss, shortened service life of the cylinder, and resulted in structural resonance during the rice threshing process. In this paper, the vibration amplitude and frequency of tangential threshing cylinder shaft were tested, and the vibration state of tangential threshing cylinder was identified. The restricted and working modalities of tangential threshing cylinder were solved by ANSYS software. Then, by comparing the resonance phenomenon between the inherent constraint frequency and the rotation speed frequency, the shaft vibration under the idle condition of tangential threshing cylinder was tested and analyzed. According to the axial vibration and axial trajectory of the cylinder, the inherent properties and characteristics of unbalanced vibration were revealed. Test results showed that when the tangential threshing cylinder was at idling and no-load state, the amplitude of vibration in the feed direction of straw flow was -0.049~0.060 mm, and the average vibration amplitude was 0.013 mm. As rice flowed along the tangential threshing cylinder, the vibration amplitude slightly increased. The trend and phase of each trajectory were similar, although the amplitude of each trajectory was different. The tangential threshing cylinder axis trajectory was flat oval. Unbalanced vibration was induced by the rice stalks in the concave gap.

The Structure Optimization Design for the W-Type Metallic Sealing Ring Based on the MOGA Algorithm

2015 ◽  
Vol 727-728 ◽  
pp. 541-545
Author(s):  
Xiang Yu Ding
Keyword(s):  
Mechanical Properties ◽  
Optimal Design ◽  
Optimization Algorithm ◽  
Optimization Design ◽  
Structure Optimization ◽  
Ansys Software ◽  
Sealing Ring ◽  
Structure Optimization Design

This paper uses the ANSYS software to analysis the outer arm opening angel(OAOA) and the outer arm arc angle(OAAA) of W-type metallic sealing ring which can effects on the mechanical properties,obtained in that when the OAOA choose from 1.398°to 14.156 °and the OAAA choose from 30.21° to 59.5 °, the mechanical properties of the sealing ring can satisfy the requirement of use. Then using the MOGA optimization algorithm to optimize the design of W-type metallic sealing ring, and find when the OAOA choose 3.39°and the OAAA choose 32.18°are the optimal design of the W-type metallic sealing ring.

Modal Analysis of Ball Screw Based on ANSYS Software

2011 ◽  
Vol 314-316 ◽  
pp. 1981-1986 ◽  
Author(s):  
Qing Ke Yuan ◽  
Ya Nan Du ◽  
Yao Ding ◽  
Tong Le Wang
Keyword(s):  
Numerical Model ◽  
Machine Tool ◽  
Modal Analysis ◽  
Structure Analysis ◽  
Ball Screw ◽  
Feeding System ◽  
Ansys Software ◽  
Intrinsic Frequency ◽  
Vibration Model

Ball screw is an important part in the machine tool feeding system. This paper researches on the ball screw, establishes the 3D virtual numerical model by Pro/engineer. Modal analysis of ball screw is carried out in three different cases by ANSYS, then gets the intrinsic frequency and vibration model of ball screw. It provides reliable reference for further structure analysis of ball screw.

scholarly journals Modeling Study on Stiffness Characteristics of Hydraulic Cylinder under Multi-Factors

2017 ◽  
Vol 63 (7-8) ◽  
pp. 447 ◽  
Author(s):  
Hao Feng ◽  
Qungui Du ◽  
Yuxian Huang ◽  
Yongbin Chi
Keyword(s):  
Mechanical System ◽  
Volume Expansion ◽  
Hydraulic Cylinder ◽  
Experimental Results ◽  
Axial Deformation ◽  
Response Characteristics ◽  
Stiffness Model ◽  
Hydraulic Cylinders ◽  
Stiffness Characteristics ◽  
Cylinder Barrel

For a complex mechanical system driven by hydraulic cylinders, the dynamic response characteristics of the mechanical system are significantly affected by the stiffness characteristics of hydraulic cylinders. This paper comprehensively studies the impacts of various factors on the stiffness characteristics of the hydraulic cylinders, including the oil bulk modulus, the air content in the hydraulic oil, the axial deformation of the piston rod, the volume expansion of the cylinder barrel, the volume expansion of the metal pipes and the flexible hoses, and the deformation of the hydraulic cylinder sealing. By combining the theoretical analysis and the experimental results, the level of each impacting factor was quantified, and the stiffness model of the hydraulic cylinder was established. Finally, comparative analysis of the stiffness was conducted by taking the experimental hydraulic cylinder as an example; it was verified that the calculated results of the proposed hydraulic cylinder stiffness model approximated the experimental results. Compared with stiffness models presented in current literature, the average accuracy was improved by more than 15 %.

Experiment Research on Square Columns Reinforced by High Strength Wire Mesh Mortar

2013 ◽  
Vol 671-674 ◽  
pp. 409-412
Author(s):  
Chun Min Dong ◽  
Ke Dong Guo
Keyword(s):  
Bearing Capacity ◽  
High Strength ◽  
Ultimate Bearing Capacity ◽  
Wire Mesh ◽  
Calculation Formula ◽  
Test Results ◽  
Axial Deformation ◽  
Experiment Research

To investigate the influence of wire mesh type, wrapped way and stress of column on the behavior of RC square columns, the experiment including an unreinforced column and 7 strengthened columns with the high strength wire mesh mortar were tested. The results were shown that the strength and axial deformation of columns reinforced by high strength wire mesh mortar were enhanced. Finally, the calculation formula for ultimate bearing capacity of the reinforced columns was given based on the test results, which agreed with the tested results well.

scholarly journals Finite-element analysis and structure optimization of X-O composite seal of cone bit

2020 ◽  
Vol 12 (5) ◽  
pp. 168781402091868
Author(s):  
Shuang Jing ◽  
Anle Mu ◽  
Yi Zhou ◽  
Ling Xie
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Structural Parameters ◽  
Structure Optimization ◽  
Seal Ring ◽  
Test Results ◽  
Element Analysis ◽  
Root Cause ◽  
Sealing Performance ◽  
Distribution Of Stress

The seal is the key part of the cone bit. To reduce the failure probability, a new seal was designed and studied. The sealing performance and structure optimization of the X-O composite seal was analyzed and compared by finite-element analysis. The stress and contact pressure were analyzed to establish the main structural parameters that affect sealing performance and the direction of the structural optimization. By optimizing these structural parameters, including the height, and the radial and axial arc radii, an optimized structure is obtained. The results show that (1) the X-O composite seal can meet the seal requirement, the excessive height of the X seal ring is the root cause of the uneven distribution of stress, pressure, and distortion. (2) A new seal structure is obtained, the distribution of pressure and stress is reasonable and even, and the values of stress and pressure are reduced to avoid distortion and reduce the wear. Finally, the field test results of the X-O composite seal of cone bit showed that the service life of the bit bearing increased by 16% on average and the drilling efficiency increased by 11% on average compared with the original cone bit with the O seal ring.

Dynamic Modeling of a Ball-Screw Drive and Identification of Its Installation Parameters

2020 ◽  
Vol 143 (4) ◽  
Author(s):  
Yu-Jia Hu ◽  
Yaoyu Wang ◽  
Weidong Zhu ◽  
Haolin Li
Keyword(s):  
Dynamic Model ◽  
Natural Frequencies ◽  
Data Fitting ◽  
Ball Screw ◽  
Mode Shapes ◽  
The Finite Element Method ◽  
Screw Drive ◽  
Log Normal ◽  
Ball Screw Drive ◽  
Log Normal Distribution

Abstract Parametric expressions of equivalent stiffnesses of a ball-screw shaft are obtained by derivation of its geometric parameters, the finite element method (FEM), and data fitting based on a modified probability density function of log-normal distribution. A dynamic model of a ball-screw drive that considers effects of bearing stiffnesses, the mass of the nut, and the axial pretension is established based on equivalent stiffnesses of its shaft. With the dynamic model and modal experimental results obtained by Bayesian operational modal analysis (BOMA), installation parameters of the ball-screw drive are identified by a genetic algorithm (GA) with a new comprehensive objective function that considers natural frequencies, mode shapes, and flexibility of the ball-screw drive. The effectiveness of the methodology is experimentally validated.

Sign in / Sign up

Export Citation Format

Share Document