On Dual Lead Worm Gears made by Simple Method of Cutting

The paper represents an attempt to establish a basis upon which the load-carrying capacity and efficiency of worm gears may be predicted. It forms a supplement to a forthcoming British Standard Specification. The requirements of a worm thread profile are briefly considered and the use of the involute helicoid as a basis of worm thread design is recommended. The geometrical properties of the involute helicoid are discussed and a simple method of determining the zone and lines of contact is given. On a theorem on the curvature of tooth profiles as basis, the relative curvature of worm threads and wheel teeth is determined. A method of comparing the stress conditions between lubricated surfaces making moving line-contact is presented and its application to the determination of the allowable loading on worm gear teeth results in simple formulæ. A comparative method of determining wheel tooth strength is also given. An experimental apparatus has been developed for investigating the friction between surfaces in lubricated line-contact, and some of the results obtained therefrom are described. The relation between the results obtained from rolling and sliding disks and from actual worm gears is discussed, and average values of the coefficient of friction which may be used in design are given.

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TOOTH CONTACT ANALYSIS AND MANUFACTURING OF DUAL LEAD WORM GEARS IN ISO TYPE I

The Proceedings of the JSME international conference on motion and power transmissions ◽

10.1299/jsmeimpt.2017.02-12 ◽

2017 ◽

Vol 2017 (0) ◽

pp. 02-12

Author(s):

Shigenori HAMADA ◽

Kazumasa KAWASAKI ◽

Isamu TSUJI

Keyword(s):

Contact Analysis ◽

Type I ◽

Tooth Contact Analysis ◽

Tooth Contact ◽

Worm Gears ◽

Dual Lead

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A simple way for producing holographic filters suitable for image improvement

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108271 ◽

1978 ◽

Vol 36 (1) ◽

pp. 226-227

Author(s):

K.-H. Herrmann ◽

E. Reuber ◽

P. Schiske

Keyword(s):

Transfer Functions ◽

Diffraction Order ◽

Lateral Position ◽

Simple Method ◽

Spatial Frequencies ◽

Resolution Electron ◽

Wiener Filters ◽

Image Improvement ◽

Optical Reconstruction ◽

Set Up

Aposteriori deblurring of high resolution electron micrographs of weak phase objects can be performed by holographic filters [1,2] which are arranged in the Fourier domain of a light-optical reconstruction set-up. According to the diffraction efficiency and the lateral position of the grating structure, the filters permit adjustment of the amplitudes and phases of the spatial frequencies in the image which is obtained in the first diffraction order.In the case of bright field imaging with axial illumination, the Contrast Transfer Functions (CTF) are oscillating, but real. For different imageforming conditions and several signal-to-noise ratios an extensive set of Wiener-filters should be available. A simple method of producing such filters by only photographic and mechanical means will be described here.A transparent master grating with 6.25 lines/mm and 160 mm diameter was produced by a high precision computer plotter. It is photographed through a rotating mask, plotted by a standard plotter.

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Rotary Beveling for In Situ Thin-Section Microscopy of Cell Cultures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099192 ◽

1981 ◽

Vol 39 ◽

pp. 550-551

Author(s):

Dean A. Handley ◽

Jack T. Alexander ◽

Shu Chien

Keyword(s):

Cell Growth ◽

Cell Cultures ◽

Molecular Interactions ◽

Convenient Method ◽

Petri Dish ◽

Simple Method ◽

Thin Section Microscopy ◽

Thin Sectioning ◽

Organic Fluids

In situ preparation of cell cultures for ultrastructural investigations is a convenient method by which fixation, dehydration and embedment are carried out in the culture petri dish. The in situ method offers the advantage of preserving the native orientation of cell-cell interactions, junctional regions and overlapping configurations. In order to section after embedment, the petri dish is usually separated from the polymerized resin by either differential cryo-contraction or solvation in organic fluids. The remaining resin block must be re-embedded before sectioning. Although removal of the petri dish may not disrupt the native cellular geometry, it does sacrifice what is now recognized as an important characteristic of cell growth: cell-substratum molecular interactions. To preserve the topographic cell-substratum relationship, we developed a simple method of tapered rotary beveling to reduce the petri dish thickness to a dimension suitable for direct thin sectioning.

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