An adjustable bearing seat stiffness element for targeted vibration influencing

2021 ◽  
Vol 263 (6) ◽  
pp. 757-766
Author(s):  
Carolin Sturm ◽  
Andreas Lindenmann ◽  
Thomas Gwosch ◽  
Sven Matthiesen
Keyword(s):  
Dynamic System ◽  
Dynamic Characteristics ◽  
High Speed ◽  
Design Space ◽  
Testing Machine ◽  
Technical System ◽  
System Behavior ◽  
Load Range ◽  
Theoretical Approaches ◽  
Universal Testing

In order to be able to influence the dynamic system behavior in a targeted manner, parameters such as stiffness in the technical system must be adjustable. In high-speed powertrains, the stiffness of the bearing seat, in particular, has an influence on the dynamic characteristics. As part of our research, we developed an adjustable bearing seat stiffness element. The focus of research was on an adjustable, scalable element with a small design space and the same properties over the perimeter. We characterized it statically with the help of a universal testing machine and dynamically using a shaker system. The results are compared with theoretical approaches. The results show that the stiffness is almost linearly adjustable in the load range of 0-100N. The results indicate that the developed element can be used to adjust desired stiffness and thus to influence vibrations in a targeted manner. The findings can be used in the design of high-speed powertrains e.g. in serial products or test benches.

scholarly journals Influence of grinding procedures on the flexural strength of zirconia ceramics

2010 ◽  
Vol 21 (6) ◽  
pp. 528-532 ◽  
Author(s):  
Ufuk İşerı ◽  
Zeynep Özkurt ◽  
Ender Kazazoğlu ◽  
Davut Küçükoğlu
Keyword(s):  
Flexural Strength ◽  
High Speed ◽  
Testing Machine ◽  
Fracture Load ◽  
Bending Test ◽  
Control Group ◽  
Zirconia Ceramics ◽  
Significance Level ◽  
Universal Testing ◽  
Short Time

The surface of zirconia may be damaged during grinding, influencing the mechanical properties of the material. The purpose of this study was to compare the flexural strength of zirconia after different grinding procedures. Twenty bar-type zirconia specimens (21 x 5 x 2 mm) were divided into 4 groups and ground using a high-speed handpiece or a low-speed straight handpiece until the bars were reduced 1 mm using two different grinding times: continuous grinding and short-time grinding (n=5). Control specimens (n=5) were analyzed without grinding. The flexural strengths of the bars were determined by using 3-point bending test in a universal testing machine at a crosshead speed of 0.5 mm/min. The fracture load (N) was recorded, and the data were analyzed statistically by the Kruskal Wallis test at a significance level of 0.05. In the test groups, high-speed handpiece grinding for a short time had produced the highest mean flexural strength (878.5 ± 194.8 MPa), while micromotor continuous grinding produced the lowest mean flexural strength (733.8 ± 94.2 MPa). The control group was the strongest group (928.4 ± 186.5 MPa). However, there was no statistically significant differences among the groups (p>0.05). Within the limitations of the study, there was no difference in flexural strength of zirconia specimens ground with different procedures.

scholarly journals Optimized One-Click Development for Topology-Optimized Structures

2021 ◽  
Vol 11 (5) ◽  
pp. 2400
Author(s):  
Tobias Rosnitschek ◽  
Rick Hentschel ◽  
Tobias Siegel ◽  
Claudia Kleinschrodt ◽  
Markus Zimmermann ◽  
...  
Keyword(s):  
Topology Optimization ◽  
Design Space ◽  
Testing Machine ◽  
Smoothing Algorithm ◽  
Test Results ◽  
Hybrid Topology ◽  
Universal Testing ◽  
The One ◽  
Finite Spheres ◽  
Digital Engineering

Topology optimization is a powerful digital engineering tool for the development of lightweight products. Nevertheless, the transition of obtained design proposals into manufacturable parts is still a challenging task. In this article, the development of a freeware framework is shown, which uses a hybrid topology optimization algorithm for stiffness and strength combined with manufacturing constraints based on finite spheres and a two-step smoothing algorithm to design manufacturable prototypes with “one click”. The presented workflow is shown in detail on a rocker, which is “one-click”-optimized and manufactured. These parts were experimentally tested using a universal testing machine. The objective of this article was to investigate the performance of “one-click”-optimized parts in comparison with manually redesigned optimized parts and the initial design space. The test results show that the design proposals created while applying the finite-spheres and two-step smoothing are equal to the manual redesigned parts based on the optimization results, proposing that the “one-click”-development can be used for the fast and direct development and fabrication of prototypes.

scholarly journals Experimental evaluation of the load capacity of the rollers of gravity conveyors for pallets

2020 ◽  
Vol 1 (3) ◽  
pp. 59-64
Author(s):  
Ye.V. Safronov ◽  
◽  
A.L. Nosko ◽  
Keyword(s):  
Load Capacity ◽  
Testing Machine ◽  
Experimental Studies ◽  
Test Results ◽  
Load Range ◽  
Universal Testing ◽  
Urgent Task ◽  
The Stability ◽  
The Cost ◽  
Roller Support

The main approaches to calculating the load capacity of the carrying rollers of gravity conveyors are presented. It is shown that in practice, in the designs of modern non-driven conveyors for pal-lets, the priority when choosing the pitch of the carrier rollers is the stability of the movement of the load, rather than minimizing the number of rollers. In connection with the urgent task of reducing the metal consumption and the cost of gravity roller conveyors for pallets, the purpose of the work is to experimentally determine the load capacity of the rollers of gravity conveyors for pallets with plastic bearing housings. The experimental studies were carried out in the laboratory of the Depart-ment of Applied Mechanics on a Galdabini Quasar 50 universal testing machine using a special roller support for two roller designs - with a solid axis and on half-axles. The test results showed that the stiffness of a roller with a solid axis in the load range up to 670 N is about 1358.4 N / mm, and in the load range from 670 to 1500 N - 2229.9 N / mm. The rigidity of the roller on the axle shafts in the entire load range is 2048.0 N / mm. The analysis of the obtained results showed that for loads over 670N the use of the axle slightly increases the stiffness coefficient, and, on the contrary, it decreases in the load range up to 670N. In order to reduce the cost of carrying rollers with plastic bearing housings, it is advisable to use a design on semi-axles.

Dynamic Characteristics of the Sinter-Forged Cu-Cr Alloys with the Variation of Chrome Content

2006 ◽  
Vol 116-117 ◽  
pp. 255-258
Author(s):  
Jung Han Song ◽  
Hoon Huh
Keyword(s):  
Dynamic Response ◽  
Dynamic Characteristics ◽  
High Speed ◽  
High Strain ◽  
Split Hopkinson Pressure Bar ◽  
Testing Machine ◽  
Impact Behavior ◽  
Stress Wave Propagation ◽  
Strain Rates ◽  
High Strain Rates

This paper is concerned with the dynamic characteristics of sinter-forged Cu–Cr alloy for various strain-rates. The amount of the chrome content is varied from 10 %wt to 30 %wt in order to investigate the influence of the chrome content on the dynamic characteristics. The dynamic response at the corresponding level of strain-rate should be obtained with an adequate experimental technique and corresponding apparatus due to the inertia effect and the stress wave propagation. In this paper, the high speed tensile testing machine is utilized in order to identify the dynamic response of the Cu–Cr alloy at the intermediate strain-rates and the split Hopkinson pressure bar is used at the high strain-rates. Experimental results from both the quasi-static and the high strain-rates up to the 5000/s are interpolated with respect to the amount of the chrome content in order to construct the Johnson–Cook and the modified Johnson–Cook model as the constitutive relation for numerical simulation of the dynamic impact behavior of electrodes.

scholarly journals Effect of Changing the Parameters of the Multi Jet Fusion (MJF) Process on the Spatial Objects Produced

2020 ◽  
Vol 11 (4) ◽  
pp. 61-72
Author(s):  
Maciej CADER ◽  
Wojciech KIŃSKI
Keyword(s):  
Tensile Test ◽  
Measurement System ◽  
High Speed ◽  
Testing Machine ◽  
Spatial Objects ◽  
Universal Testing Machine ◽  
Universal Testing ◽  
Static Tensile Test ◽  
Strength Tests ◽  
Static Tensile

This paper describes the principle of operation of Multi Jet Fusion (MFJ) technology in detail. Hybrid strength tests were carried out using an INSTRON 5967 universal testing machine controlled by the Bluehill 3 program and coupled with the ARAMIS measurement system (GOM, Gmbh), enabling the monitoring of deformations in three axes, using a system of high-speed cameras. The results are given of the static tensile test of samples in two printing modes characteristic of the MJF technology – FAST and BALANCE.

Bioinspired Crown-Cutter—The Impact of Tooth Quantity and Bevel Type on Tissue Deformation, Penetration Forces, and Tooth Collapsibility

2014 ◽  
Vol 8 (4) ◽  
Author(s):  
Filip Jelínek ◽  
Jeffrey Goderie ◽  
Alice van Rixel ◽  
Daan Stam ◽  
Johan Zenhorst ◽  
...  
Keyword(s):  
High Speed ◽  
Surface Deformation ◽  
Testing Machine ◽  
High Ratio ◽  
Steady Increase ◽  
Tissue Deformation ◽  
Universal Testing ◽  
Significant Difference ◽  
The Impact ◽  
Speed And Accuracy

Current keyhole biopsy devices are rather ungainly, inaccurate, and limited in application. A keyhole biopsy harvester was designed to facilitate peripheral cancerous tissue detection and resection at high speed and accuracy. The harvester's cutting tool, the crown-cutter, was bioinspired by the sea urchin's chewing organ—Aristotle's lantern. This paper focuses on the optimization of the crown-cutter with regard to the impact of different tooth quantity and bevel type on tissue deformation, penetration forces, and tooth collapsibility. Two sets of crown-cutter designs were manufactured and tested in push-in experiments using gelatin—the first set having no bevel and differing tooth quantity (4, 6, 8, 10 teeth) and the second set of constant tooth quantity and differing bevel type (no, inner, outer, and inner and outer bevel). The gelatin surface deformation and the penetration forces were evaluated utilizing a high speed camera and a universal testing machine, respectively. The experimental results on the crown-cutters of different tooth quantity (no bevel) showed a steady increase in the tissue deformation with the increasing amount of teeth. Unlike the bevel type, the different tooth quantity revealed significant differences with regard to the tissue deformation in between 4 versus 6-teeth and 10 versus 6-teeth cutters. As for the penetration forces, the significant difference was found only between 10 and 6-teeth cutters. In conclusion, reducing the cutter's tooth quantity resulted in lower tissue deformation, whereas differing the bevel type was found to have a negligible influence. Ultimately, a high ratio of outward to inward tooth collapsibility and a relatively low inner moment of inertia proved the 6-teeth cutter to be the most optimal.

Dynamic analysis of enhanced gear transmissions in the vehicle-track coupled dynamic system of a high-speed train

2021 ◽  
pp. 1-23
Author(s):  
Zhiwei Wang ◽  
Zhonghui Yin ◽  
Paul Allen ◽  
Ruichen Wang ◽  
Qing Xiong ◽  
...  
Keyword(s):  
Dynamic System ◽  
Dynamic Analysis ◽  
High Speed ◽  
High Speed Train

Crush Response of Polyurethane Foam-Filled Aluminium Tube Subjected to Axial Loading

2014 ◽  
Vol 875-877 ◽  
pp. 534-541 ◽  
Author(s):  
Chawalit Thinvongpituk ◽  
Nirut Onsalung
Keyword(s):  
Energy Absorption ◽  
Polyurethane Foam ◽  
Testing Machine ◽  
Axial Loading ◽  
Asymmetric Mode ◽  
Pu Foam ◽  
Universal Testing ◽  
Collapse Mode ◽  
Empty Tube ◽  
Foam Filled

In this paper, the experimental investigation of polyurethane (PU) foam-filled into circular aluminum tubes subjected to axial crushing was presented. The purpose of this study is to improve the energy absorption of aluminium tube under axial quasi-static load. The aluminium tube was made from the AA6063-T5 aluminium alloy tubes. Each tube was filled with polyurethane foam. The density of foam was varied from 100, 150 and 200 kg/mP3P including with empty tube. The range of diameter/thickness (D/t) ratio of tube was varied from 15-55. The specimen were tested by quasi-static axial load with crush speed of 50 mm/min using the 2,000 kN universal testing machine. The load-displacement curves while testing were recorded for calculation. The mode of collapse of each specimen was analyzed concerning on foam density and the influence of D/t ratio. The results revealed that the tube with foam-filled provided significantly increment of the energy absorption than that of the empty tube. While the density of foam and D/t ratios increase, the tendency of collapse mode is transformed from asymmetric mode to concertina mode.

A modified damping model of vector form intrinsic finite element method for high-speed spiral bevel gear dynamic characteristics analysis

2021 ◽  
pp. 030932472110188
Author(s):  
Xiangying Hou ◽  
Yuzhe Zhang ◽  
Hong Zhang ◽  
Jian Zhang ◽  
Zhengminqing Li ◽  
...  
Keyword(s):  
Finite Element ◽  
Dynamic Characteristics ◽  
High Speed ◽  
Numerical Solutions ◽  
Bevel Gear ◽  
Spiral Bevel Gear ◽  
Vector Form ◽  
Good Efficiency ◽  
Spiral Bevel ◽  
Damping Model

The vector form intrinsic finite element (VFIFE) method is springing up as a new numerical method in strong non-linear structural analysis for its good convergence, but has been constricted in static or transient analysis. To overwhelm its disadvantages, a new damping model was proposed: the value of damping force is proportional to relative velocity instead of absolute velocity, which could avoid inaccuracy in high-speed dynamic analysis. The accuracy and efficiency of the proposed method proved under low speed; dynamic characteristics and vibration rules have been verified under high speed. Simulation results showed that the modified VFIFE method could obtain numerical solutions with good efficiency and accuracy. Based on this modified method, high-speed vibration rules of spiral bevel gear pair under different loads have been concluded. The proposed method also provides a new way to solve high-speed rotor system dynamic problems.

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