Stiffness of a ball screw with consideration of deformation of the screw, net and screw thread. Preloaded double nut.

At present, one of the most pressing issues is the problem of improving electromechanical drive reliability, specifically, eliminating the possibility of jamming in the ball screw. The paper proposes an engineering solution designed to replace expensive imported ball screws. We analysed alternative designs intended to improve electromechanical drive reliability. We proposed and patented a ball screw design featuring a separator, in which the nut acts as a piston. The structure consists of a smooth cylindrical body and a slotted separator, its slots positioned along a helical line with a step equal to the thread lead. The body and the separator are coaxial and rigidly fixed together at the separator end faces so that the rolling elements remain in contact with the screw thread surfaces, the internal smooth cylindrical surface of the nut body and the surfaces of the separator slots. The ball screw design proposed, which features a nut with no internal threading, significantly simplifies the structure and its manufacturing technology. We built a model of an electromechanical drive equipped with a recirculating ball screw in order to determine static and dynamic properties of an electromechanical drive containing a ball screw featuring a separator. We compared the strength of the ball screw designs considered. As the ball screw featuring a separator is simpler and more reliable, the results of our analysis and the properties of an electromechanical drive equipped with the design proposed show that it is a promising solution to the import substitution problem concerning recirculating ball screws

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Stiffness of a ball screw including with consideration to deformation of the screw, nut and screw thread. (2nd Report, Preloaded double nuts).

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C ◽

10.1299/kikaic.55.1734 ◽

1989 ◽

Vol 55 (515) ◽

pp. 1734-1740

Author(s):

Kazuki TAKAHASHI ◽

Katsuhiro NAKASHIMA

Keyword(s):

Ball Screw ◽

Screw Thread

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Stiffness of a Ball Screw Including with Consideration to Deformation of the Screw, Nut and Screw Thread. 3rd Report, Effect of Contact Angle Change.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C ◽

10.1299/kikaic.57.2041 ◽

1991 ◽

Vol 57 (538) ◽

pp. 2041-2046

Author(s):

Kazuki TAKAFUJI ◽

Katuhiro NAKASHIMA

Keyword(s):

Contact Angle ◽

Ball Screw ◽

Screw Thread ◽

Angle Change

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A novel non-contact measuring system for the thread profile of a ball screw

Mechanical Sciences ◽

10.5194/ms-9-15-2018 ◽

2018 ◽

Vol 9 (1) ◽

pp. 15-24 ◽

Cited By ~ 3

Author(s):

Leilei Zhao ◽

Hutian Feng ◽

Qianfeng Rong

Keyword(s):

Ccd Camera ◽

Measuring System ◽

Ball Screw ◽

Screw Thread ◽

Outer Contour ◽

High Position ◽

Position Accuracy ◽

Thread Profile ◽

Data Points ◽

Target Data

Abstract. In order to meet the demand of high position accuracy, many methods have been developed for measuring the thread profile features of ball screws. However, most of these efforts are limited to measuring a small number of ball screw features and therefore less efficient. In this study, an automatic, non-contact measuring system for the thread profile of a ball screw was developed. It is capable of measuring most common features of the ball screw thread profile and can measure ball screws of different sizes and lengths. The main part of the system is the light curtain which has a high-resolution line-scan CCD camera to measure the projected outer contour of the target. Data points from the thread profile of a ball screw were collected by the measuring system and data pre-processing was performed. Then, the proposed method was used to calculate the most important geometric parameters and errors of the thread profile. The accuracy of the measuring system was verified by testing and evaluating four sets of ball screws from different manufacturers.

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Microdensitometer—computer correlation analysis of ultrastructural periodicity

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081024 ◽

1978 ◽

Vol 36 (2) ◽

pp. 32-33

Author(s):

D.R. Ensor ◽

C.G. Jensen ◽

J.A. Fillery ◽

R.J.K. Baker

Keyword(s):

Correlation Analysis ◽

Background Noise ◽

Computer Control ◽

Optical Diffraction ◽

Screw Thread ◽

Straight Line ◽

Computer Storage ◽

Correlation Process ◽

Electron Microscope Image ◽

Fixed Beam

Because periodicity is a major indicator of structural organisation numerous methods have been devised to demonstrate periodicity masked by background “noise” in the electron microscope image (e.g. photographic image reinforcement, Markham et al, 1964; optical diffraction techniques, Horne, 1977; McIntosh,1974). Computer correlation analysis of a densitometer tracing provides another means of minimising "noise". The correlation process uncovers periodic information by cancelling random elements. The technique is easily executed, the results are readily interpreted and the computer removes tedium, lends accuracy and assists in impartiality.A scanning densitometer was adapted to allow computer control of the scan and to give direct computer storage of the data. A photographic transparency of the image to be scanned is mounted on a stage coupled directly to an accurate screw thread driven by a stepping motor. The stage is moved so that the fixed beam of the densitometer (which is directed normal to the transparency) traces a straight line along the structure of interest in the image.

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