Fundamental study on machine tools equipped with vibration suppression mechanism based on left and right ball screw and with an ultra-high speed spindle for micro-drilling

The general trend in the field of machine tools is to increase the speed of feed axes with the aim of reducing manufacturing times, high speed machining is a significant example of such increase. Ball screws have proven their ability to fulfill requirements of workpiece positioning accuracy, nevertheless, the heat generated in the screw-nut interaction increases proportionally with the speed of the axes. As a result, an increase in temperature takes place, which causes thermal expansion of the ball screw, producing positioning errors and decreasing the service life of the ball screws, therefore it is important to have effective methods for predict the temperature.The main objective of the present work is to predict the heat generated in the screw-nut contact based on analytical models in order to estimate the temperature distribution in the nut. For this purpose a heat transfer FE model of a preloaded high speed ball screw nut has been developed. Additionally, experimental heating tests have been performed to validate the FE numerical model. In this way, the temperature predictions obtained at different working conditions have less than 6% of deviation comparing with the experimental results.

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Research on MFBD Modeling Method for a Gantry Machining Center Beam Components

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.188.487 ◽

2011 ◽

Vol 188 ◽

pp. 487-492 ◽

Cited By ~ 1

Author(s):

Q.J. Yang ◽

D.N. Li ◽

L.L. Kong ◽

K. Li

Keyword(s):

Machine Tool ◽

Machine Tools ◽

High Speed ◽

Modeling Method ◽

Ball Screw ◽

Machining Processes ◽

Element Analysis ◽

Machining Center ◽

Body Dynamics ◽

Multi Body

In modern machining processes, Gantry Machining Center is one of the most important machine tools. Moreover, beam components directly relate to the overall performance. From multi-body simulation (MBS) and finite element analysis (FEA) respectively, the paper discusses current state of the multi-body dynamics modelling of the machine tool components in domestic and overseas. In this paper, We adopt a method, the multi-flexible body dynamics(MFBD) modeling method for machine tool transmission components (linear guidance and ball screw drives) in software Recurdyn, to create the conditions for MFBD simulation analysis of the beam components system. Much more, it provides a way of MFBD modelling for machine tools components in both the high-speed and high-performance.

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Improvement of Thermal Deformation in a Newly Developed Steel CFRP Composite Ball Screw

JSME 2020 Conference on Leading Edge Manufacturing/Materials and Processing ◽

10.1115/lemp2020-8587 ◽

2020 ◽

Author(s):

Hayato Yoshioka ◽

Shunya Saito ◽

Jun Kato ◽

Hidenori Shinno ◽

Shunsuke Goto ◽

...

Keyword(s):

Machine Tools ◽

High Speed ◽

High Performance ◽

Thermal Deformation ◽

High Efficiency ◽

Cooling System ◽

Cutting Tools ◽

Large Error ◽

Ball Screw ◽

Positioning Accuracy

Abstract Machine tools are required to realize high precision and high efficiency machining by various industry sectors. A machine tool has some driving systems to position cutting tools and workpieces, and hence driving units are required high speed and precision positioning. However, high speed feed motion causes thermal deformation due to generated heat at friction surfaces such as guideway, feed screw, and bearings, it deteriorates positioning accuracy of driving units. Thermal deformation of a ball screw is one of large error factors of lower positioning accuracy, and a cooling system for reducing thermal deformation is installed into machine tools. Since the cooling system needs additional cost and space in machining systems, a new method for minimizing thermal deformation is required. In this study, a new structure of ball screw is proposed in order to meet these requirements. A new ball screw which has a core pipe made of CFRP was developed. CFRP is one of composite materials which have light weight and low thermal expansion. This paper presents analysis results of a simplified FEM model of the ball screw and the basic experimental results of the developed ball screw. These results confirmed that the proposed ball screw was applied to high performance positioning system in machine tools.

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