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Multi-Diameter Vise Clamp And Collet Jaw, Lloyd D. Snell Nov 2000

Multi-Diameter Vise Clamp And Collet Jaw, Lloyd D. Snell

Lloyd D Snell

A machine vise has incorporated into it a pair of collet jaws that allows for the machining of top surfaces and ends of a held part. The collet jaws are secured to each of the clamping blocks on the machine vise. The collet jaws include at least one collet pocket shaped into the inside surface of each collet jaw. The collet pockets are designed to receive collet pads which are shaped to hold a generally cylindrical part with varying diameters. By having more than one collet pocket within each collet jaw, several different sizes of collet pads can be utilized ...


Statistical Representation Of A Spray As A Point Process, Shankar Subramaniam Oct 2000

Statistical Representation Of A Spray As A Point Process, Shankar Subramaniam

Shankar Subramaniam

The statistical representation of a spray as a finite point process is investigated. One objective is to develop a better understanding of how single-point statistical information contained in descriptions such as the droplet distribution function ~ddf!, relates to the probability density functions ~pdfs! associated with the droplets themselves. Single-point statistical information contained in the droplet distribution function ~ddf! is shown to be related to a sequence of single surrogate-droplet pdfs, which are in general different from the physical single-droplet pdfs. It is shown that the ddf contains less information than the fundamental single-point statistical representation of the spray, which is ...


Damper For Brake Noise Reduction (Brake Drums), Jonathan A. Wickert, Adnan Akay Sep 2000

Damper For Brake Noise Reduction (Brake Drums), Jonathan A. Wickert, Adnan Akay

Jonathan A. Wickert

An apparatus of reducing unwanted brake noise has a ring damper affixed around a periphery of brake drum in a drum brake system in a manner that permits relative motion and slippage between the ring damper and the brake drum when the brake drum vibrates during braking. In a preferred embodiment, the ring damper is an almost circular ring that is inserted in a groove formed in the periphery of the brake drum. The ring damper is held in place by the groove itself and by the interference pre-load or pre-tension between the ring damper and the brake drum.


Tribological Behaviour Of Quenched And Tempered, And Austempered Ductile Iron At The Same Hardness Level Sep 2000

Tribological Behaviour Of Quenched And Tempered, And Austempered Ductile Iron At The Same Hardness Level

A.S. Md Abdul Haseeb

The tribological behaviour of ductile iron heat-treated by two different procedures viz. quenching and tempering, and austempering to an identical matrix hardness of 445 KHN is compared. Wear tests were carried out using a pin-on-disc type apparatus under dry sliding conditions at a linear speed of 1.18 m s -1. Applied load and sliding distance in the range of 7.5-30 N and 2x10 4-6x10 4 m, respectively, were used. It was observed that under all test conditions, austempered ductile iron exhibits a better wear resistance than quenched and tempered ductile iron, although both have an identical chemical composition ...


An Experimental Study Of Molten Microdroplet Surface Deposition And Solidification: Transient Behavior And Wetting Angle Dynamics, Daniel Attinger, Z. Zhao, D. Poulikakos Apr 2000

An Experimental Study Of Molten Microdroplet Surface Deposition And Solidification: Transient Behavior And Wetting Angle Dynamics, Daniel Attinger, Z. Zhao, D. Poulikakos

Daniel Attinger

The basic problem of the impact and solidification of molten droplets on a substrate is of central importance to a host of processes. An important and novel such process in the area of micromanufacturing is solder jetting where microscopic solder droplets are dispensed for the attachment of microelectronic components. Despite the recent appearance of a few numerical studies focusing on the complex transient aspects of this process, no analogous experimental results have been reported to date to the best of our knowledge. Such a study is reported in this paper. Eutectic solder (63Sn37Pb) was melted to a preset superheat and ...


Lighting Display And Assembly Kit, Lloyd D. Snell Jan 2000

Lighting Display And Assembly Kit, Lloyd D. Snell

Lloyd D Snell

A versatile lighting decoration has a display sheet fabricated from a transparent and resilient film. An outline of a predetermined shape is marked on the film and a plurality of apertures placed through and along the outline. A string of lights having multiple bulbs, each bulb fitted within a socket adapted for gripping the display sheet, is releasably secured in the apertures to generate a lighted image of the predetermined shape that may be highlighted by one or more additional strings of lights.


Effect Of Mechanical Factors On Tribological Properties Of Palm Oil Methyl Ester Blended Lubricant Jan 2000

Effect Of Mechanical Factors On Tribological Properties Of Palm Oil Methyl Ester Blended Lubricant

A.S. Md Abdul Haseeb

The effects of mechanical factors viz. applied load and temperature on the tribological performance of 5% palm oil methyl ester (POME) blended lubricant were studied using a steel-cast iron pair. Wear and frictional measurements were made using a stationary steel ball and a reciprocating cast iron plate in a modified universal wear and friction testing machine. The test conditions were contact pressure, 400 MPa; mean contact velocity, 0.34 m/s; reciprocating stroke, 80 mm; loads, 100-1100 N (fixed temperature); and temperature, 40-140°C (fixed load). Wear scar surfaces were investigated using scanning electron microscopy (SEM) to understand the wear ...


Topography-Induced Contributions To Friction Forces Measured Using An Atomic Force/Friction Force Microscope, Sriram Sundararajan, Bharat Bhushan Jan 2000

Topography-Induced Contributions To Friction Forces Measured Using An Atomic Force/Friction Force Microscope, Sriram Sundararajan, Bharat Bhushan

Sriram Sundararajan

Most friction studies using an atomic force/friction force microscope, while concentrating on material-induced effects, often present users with conflicting and confusing interpretations of the topography-induced friction forces. It has been generally reported that topography-induced contributions are independent of scanning direction and can be removed by subtracting friction data from forward and backward scans. In this article, we present friction studies on samples with well-defined topography variations and find that the above-given statement is not generally true. At surface locations involving significant changes in topography, the topography-induced contributions to friction forces are found to be different between forward and backward ...


Spatial Modulation Of Repeated Vibration Modes In Rotationally Periodic Structures, M. Kim, J. Moon, Jonathan A. Wickert Jan 2000

Spatial Modulation Of Repeated Vibration Modes In Rotationally Periodic Structures, M. Kim, J. Moon, Jonathan A. Wickert

Jonathan A. Wickert

When a structure deviates from axisymmetry because of circumferentially varying model features, significant changes can occur to its natural frequencies and modes, particularly for the doublet modes that have non-zero nodal diameters and repeated natural frequencies in the limit of axisymmetry. Of technical interest are configurations in which inertia, dissipation, stiffness, or domain features are evenly distributed around the structure. Aside from the well-studied phenomenon of eigenvalue splitting, whereby the natural frequencies of certain doublets split into distinct values, modes of the axisymmetric structure that are precisely harmonic become contaminated with certain additional wavenumbers. From analytical, numerical, and experimental perspectives ...


In Situ Transmission Electron Microscopy Study Of Electric-Field-Induced Microcracking In Single Crystal Pb(Mg1/3nb2/3)O3–Pbtio3, Z. Xu, Xiaoli Tan, P. Han, J.K. Shang Jan 2000

In Situ Transmission Electron Microscopy Study Of Electric-Field-Induced Microcracking In Single Crystal Pb(Mg1/3nb2/3)O3–Pbtio3, Z. Xu, Xiaoli Tan, P. Han, J.K. Shang

Xiaoli Tan

In this letter, we report in situ transmission electron microscopy (TEM) study of effect of a cyclic electric field on microcracking in a single crystal piezoelectric 0.66Pb(Mg1/3Nb2/3)O3–0.34PbTiO3. A TEM heating stage was modified to permit the in situ application of an electric field on the TEM sample surface. Microcrack initiation from a fine pore under an applied cyclic electric field was directly observed in the piezoelectric single crystal. Experimental procedures for in situ TEM studies were described.


Rapid Solidification: Fundamentals And Modeling, Guo-Xiang Wang, Vish Prasad Dec 1999

Rapid Solidification: Fundamentals And Modeling, Guo-Xiang Wang, Vish Prasad

Dr. Guo-Xiang Wang

No abstract provided.