A Milling Torquemeter of Planetary-Gear Design

1961 ◽  
Vol 83 (2) ◽  
pp. 155-161
Author(s):  
J. R. Roubik
Keyword(s):  
Cutting Force ◽  
Single Point ◽  
Planetary Gear ◽  
Multiple Point ◽  
Gear Design ◽  
Cutting Energy ◽  
Design Considerations ◽  
Cutting Test ◽  
Milling Operations ◽  
High Degree

A design of planetary-gear dynamometer or torquemeter, to measure tangential cutting forces in milling with a high degree of accuracy and sensitivity is described together with certain design considerations and limitations as well as associated force-measuring equipment. This device is a highly efficient, sensitive, and durable research tool for use in accurately determining the magnitude and manner of variation of the cutting force, energy, and power at the cutting edges of single-point or multiple-point milling cutters, as well as machine efficiency, in full-scale milling operations. Procedures and methods of determining values of tangential cutting force, specific cutting energy, and horsepower at the cutter from cutting-test data obtained with the torquemeter are given with examples.

Milling Forces Measured With a Planetary-Gear Torquemeter

1961 ◽  
Vol 83 (4) ◽  
pp. 579-586 ◽  
Author(s):  
J. R. Roubik
Keyword(s):  
Cutting Force ◽  
High Efficiency ◽  
Comparative Method ◽  
Cutting Speed ◽  
Planetary Gear ◽  
Tool Geometry ◽  
Depth Of Cut ◽  
Gear Design ◽  
Milling Forces ◽  
Force Data

Cutting-force data, obtained with a torquemeter of planetary-gear design in carbide milling tests on SAE-1018 cold-rolled steel at feeds from 0.002 to 0.030 in. per tooth, cutting speeds from 87 to 957 fpm, and depths of cut from 0.100 to 0.300 in. with a tool geometry of −7°, 0°, 3°, 5°, 0°, 15°, 1/64″ × 45°, are presented. The influences of variations in cutting speed, feed per tooth, and depth of cut on tangential cutting force are depicted graphically. Cutting-force values for other workpiece materials are also included. With these data a comparative method of experimentally verifying the computed high efficiency of the torquemeter itself is derived and applied. A method of obtaining highly accurate determinations of milling machine efficiency under actual oscillatory cutting loads is described with an example. Actual and theoretical traces of the variation of tangential cutting force with both single and multiple-toothed face milling cutters are illustrated for comparison.

scholarly journals Design and Test Research on Cutting Blade of Corn Harvester Based on Bionic Principle

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Kunpeng Tian ◽  
Xianwang Li ◽  
Bin Zhang ◽  
Qiaomin Chen ◽  
Cheng Shen ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Cutting Force ◽  
High Energy ◽  
Superior Performance ◽  
Cutting Energy ◽  
Cutting Test ◽  
Average Maximum ◽  
Bionic Blade ◽  
Cut Quality ◽  
Blade Cutting

Existing corn harvester cutting blades have problems associated with large cutting resistance, high energy consumption, and poor cut quality. Using bionics principles, a bionic blade was designed by extracting the cutting tooth profile curve of the B. horsfieldi palate. Using a double-blade cutting device testing system, a single stalk cutting performance contrast test for corn stalks obtained at harvest time was carried out. Results show that bionic blades have superior performance, demonstrated by strong cutting ability and good cut quality. Using statistical analysis of two groups of cutting test data, the average cutting force and cutting energy of bionic blades and ordinary blades were obtained as 480.24 N and 551.31 N and 3.91 J and 4.38 J, respectively. Average maximum cutting force and cutting energy consumption for the bionic blade were reduced by 12.89% and 10.73%, respectively. Variance analysis showed that both blade types had a significant effect on maximum cutting energy and cutting energy required to cut a corn stalk. This demonstrates that bionic blades have better cutting force and energy consumption reduction performance than ordinary blades.

Surface Roughness and Cutting Force Components Evaluation in Hard Turning by Differently Shaped Cutting Tools

2016 ◽  
Vol 862 ◽  
pp. 26-32 ◽  
Author(s):  
Michaela Samardžiová
Keyword(s):  
Surface Roughness ◽  
Cutting Force ◽  
Hard Turning ◽  
Cutting Tool ◽  
Single Point ◽  
Machining Process ◽  
Tool Geometry ◽  
Machined Surface ◽  
Cutting Force Components ◽  
Force Components

There is a difference in machining by the cutting tool with defined geometry and undefined geometry. That is one of the reasons of implementation of hard turning into the machining process. In current manufacturing processes is hard turning many times used as a fine finish operation. It has many advantages – machining by single point cutting tool, high productivity, flexibility, ability to produce parts with complex shapes at one clamping. Very important is to solve machined surface quality. There is a possibility to use wiper geometry in hard turning process to achieve 3 – 4 times lower surface roughness values. Cutting parameters influence cutting process as well as cutting tool geometry. It is necessary to take into consideration cutting force components as well. Issue of the use of wiper geometry has been still insufficiently researched.

scholarly journals Preparation and cutting performance of nano-scaled Al2O3-coated micro-textured cutting tool prepared by atomic layer deposition

2021 ◽  
Vol 40 (1) ◽  
pp. 77-86
Author(s):  
Siwen Tang ◽  
Pengfei Liu ◽  
Zhen Su ◽  
Yu Lei ◽  
Qian Liu ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Atomic Layer Deposition ◽  
Cutting Force ◽  
Cutting Tool ◽  
Orthogonal Cutting ◽  
Cutting Tools ◽  
Atomic Layer ◽  
Cutting Performance ◽  
Cutting Test ◽  
Layer Deposition

Abstract Al2O3 nano-scaled coating was prepared on micro-textured YT5 cemented carbide cutting tools by atomic layer deposition ALD. The effect of Al2O3 nano-scaled coating, with and without combined action of texture, on the cutting performance was studied by orthogonal cutting test. The results were compared with micro-textured cutting tool and YT5 cutting tool. They show that the micro-texture and nano-scaled Al2O3 coated on the micro-texture both can reduce the cutting force and friction coefficient of the tool, and the tools with nano-scaled Al2O3 coated on the micro-texture are more efficient. Furthermore, the friction coefficient of the 100 nm Al2O3-coated micro-texture tool is relatively low. When the distance of the micro-pits is 0.15 mm, the friction coefficient is lowest among the four kinds of pit textured nanometer coating tools. The friction coefficient is the lowest when the direction of the groove in strip textured nanometer coating tool is perpendicular to the main cutting edge. The main mechanism of the nanometer Al2O3 on the micro-textured tool to reduction in cutting force and the friction coefficient is discussed. These results show that the developed tools effectively decrease the cutting force and friction coefficient of tool–chip interface.

The Sun and Planetary Gear Design of a 1.5-MW Wind Turbine

2018 ◽  
Vol 6 (6) ◽  
pp. 495-501 ◽  
Author(s):  
Guanjin Li ◽  
Wenyi Liu ◽  
Xiuping Su
Keyword(s):  
Wind Turbine ◽  
Planetary Gear ◽  
The Sun ◽  
Gear Design

Ultrasonic Cutting of Switchgrass and Miscanthus Stems

2018 ◽  
Vol 34 (2) ◽  
pp. 343-353
Author(s):  
A. Bulent Koc Koc ◽  
Bo Liu
Keyword(s):  
Cutting Force ◽  
Cutting Forces ◽  
High Frequency ◽  
Cutting Speed ◽  
Particle Size Reduction ◽  
Element Analysis ◽  
Cutting Energy ◽  
High Frequency Vibrations ◽  
Ultrasound Assisted ◽  
Ultrasonic Cutting

Abstract. Ultrasound-assisted cutting has been used to cut materials with high precision, improved quality and reduced cutting forces. The research objective was to investigate the effects of high-frequency vibrations on the cutting force and cutting energy of switchgrass and miscanthus stems. Laboratory experiments were conducted on individual biomass stems at cutting speeds between 3 and 400 mm/s. An experimental cutting system with an ultrasound generator, an ultrasonic blade, a load cell, and a data acquisition system was developed. The custom designed blade was 5-cm wide and vibrated at 19.551 kHz with 2.8 µm tip vibration amplitude. There were significant measured differences in the cutting forces and cutting energies between conventional cutting and ultrasonic cutting of switchgrass and miscanthus stems (p < 0.05). These results suggest that the use of high-frequency vibrations reduce cutting force and cutting energy of both switchgrass and miscanthus stems. Ultrasound-assisted cutting reduced the cutting energy of switchgrass by 66.85% at 100 mm/s and miscanthus by 80.58% at 30 mm/s. However, ultrasonic cutting did not have a significant effect on the cutting force and cutting energy when the cutting speed was equal to or greater than the blade tip vibration speed. The results of this research should be useful for adapting the ultrasonic technology in biomass harvesting, particle size reduction, and processing equipment. Keywords: Biomass, Blades, Energy, Finite element analysis, Miscanthus, Switchgrass, Ultrasonics.

scholarly journals On the point-source approximation of earthquake dynamics

2014 ◽  
Vol 57 (3) ◽  
Author(s):  
Andrea Bizzarri
Keyword(s):  
Point Source ◽  
Seismic Waves ◽  
Single Point ◽  
Seismic Source ◽  
Transition Process ◽  
Point Sources ◽  
Multiple Point ◽  
Earthquake Dynamics ◽  
Planar Fault ◽  
Source Models

<p>The focus on the present study is on the point-source approximation of a seismic source. First, we compare the synthetic motions on the free surface resulting from different analytical evolutions of the seismic source (the Gabor signal (G), the Bouchon ramp (B), the Cotton and Campillo ramp (CC), the Yoffe function (Y) and the Liu and Archuleta function (LA)). Our numerical experiments indicate that the CC and the Y functions produce synthetics with larger oscillations and correspondingly they have a higher frequency content. Moreover, the CC and the Y functions tend to produce higher peaks in the ground velocity (roughly of a factor of two). We have also found that the falloff at high frequencies is quite different: it roughly follows ω<span><sup>−2</sup></span> in the case of G and LA functions, it decays more faster than ω<span><sup>−2</sup></span> for the B function, while it is slow than ω<span><sup>−1</sup></span> for both the CC and the Y solutions. Then we perform a comparison of seismic waves resulting from 3-D extended ruptures (both supershear and subshear) obeying to different governing laws against those from a single point-source having the same features. It is shown that the point-source models tend to overestimate the ground motions and that they completely miss the Mach fronts emerging from the supershear transition process. When we compare the extended fault solutions against a multiple point-sources model the agreement becomes more significant, although relevant discrepancies still persist. Our results confirm that, and more importantly quantify how, the point-source approximation is unable to adequately describe the radiation emitted during a real world earthquake, even in the most idealized case of planar fault with homogeneous properties and embedded in a homogeneous, perfectly elastic medium.</p>

scholarly journals Early Morphologic Alterations in Renal Artery Wall and Renal Nerves in Response to Catheter-Based Renal Denervation Procedure in Sheep: Difference Between Single-Point and Multiple-Point Ablation Catheters

2017 ◽  
pp. 601-614 ◽  
Author(s):  
M. TÁBORSKÝ ◽  
D. RICHTER ◽  
Z. TONAR ◽  
T. KUBÍKOVÁ ◽  
A. HERMAN ◽  
...  
Keyword(s):  
Renal Artery ◽  
Resistant Hypertension ◽  
Renal Denervation ◽  
Single Point ◽  
Renal Tissue ◽  
Renal Nerves ◽  
Multiple Point ◽  
Renal Nerve ◽  
Jude Medical ◽  
Novel Strategy

Renal sympathetic hyperactivity is critically involved in hypertension pathophysiology; renal denervation (RDN) presents a novel strategy for treatment of resistant hypertension cases. This study assessed effects of two RDN systems to detect acute intravascular, vascular and peri-vascular changes in the renal artery, and renal nerve alterations, in the sheep. The procedures using a single-point or multi-point ablation catheters, Symplicity FlexTM, Medtronic versus EnligHTNTM, St. Jude Medical were compared; the intact contralateral kidneys served as controls. Histopathological and immunohistochemical assessments were performed 48 h after RDN procedures; the kidney and suprarenal gland morphology was also evaluated. Special staining methods were applied for histologic analysis, to adequately score the injury of renal artery and adjacent renal nerves. These were more pronounced in the animals treated with the multi-point compared with the single-point catheter. However, neither RDN procedure led to complete renal nerve ablation. Forty-eight hours after the procedure no significant changes in plasma and renal tissue catecholamines were detected. The morphologic changes elicited by application of both RDN systems appeared to be dependent on individual anatomical variability of renal nerves in the sheep. Similar variability in humans may limit the therapeutic effectiveness of RDN procedures used in patients with resistant hypertension.

SKIN TESTING WITH LIQUID OLD TUBERCULIN WITH A MULTIPLE PUNCTURE TECHNIQUE

PEDIATRICS ◽  
1968 ◽  
Vol 42 (3) ◽  
pp. 465-470
Author(s):  
Harvey Kravitz ◽  
Fredric Burg ◽  
Robert B. Lawson
Keyword(s):  
Skin Testing ◽  
Mantoux Test ◽  
Multiple Point ◽  
Plastic Ring ◽  
Multiple Points ◽  
Point Test ◽  
Tuberculin Testing ◽  
High Degree ◽  
Multiple Puncture ◽  
Puncture Technique

An improved multiple puncture technique (MPT) for tuberculin testing is applied with a nine-pointed plastic ring covered by a tube containing a specially concentrated liquid tuberculin. A high degree of positive and negative agreement was obtained with this test when compared to the Mantoux test (PPD, 5 TU). The reactions from the multiple puncture technique are discrete, single, and circular, and they are easy to read and measure. Erythema and induration from this test are smaller than from the Mantoux test (PPD, 5 TU). Children appear to show less fear and felt less pain with the multiple point test than with the Mantoux test. "Wet" tuberculin on multiple points eliminates two possible variables associated with "dry" tuberculin on the points–the length of time that the tines are held in the skin and the moisture content of the skin.

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