Akio Kubo

A Practical Approach to Estimating Corner Errors in Contour Cutting with Machining Center

This paper proposes a practical approach to estimating the corner errors in contour cutting with a machining center. In this approach, only a few simple and easy trajectory measurements to linear feed motion of machining center are required and then the value of each necessary parameter is decided through a simple operation to the measured data. The comparison results of the estimated corner errors with the measured ones sufficiently demonstrate the effectiveness of the proposed approach.

Influence of water-miscible cutting fluid on tool wear behavior of various coated high-speed steel tools in hobbing

This paper deals with the influence of water-miscible cutting fluid on tool life (flank wear) compared with that with dry cutting and water-insoluble cutting oil in hobbing. Experiments were conducted by simulating hobbing by fly tool cutting on a milling machine. The following results were clarified. (1) The water-miscible cutting fluid used in the test prolongs the tool life for TiN-, TiAlN-, TiSiN- and AlCrSiN-coated tools in comparison with that obtained by dry cutting and water-insoluble cutting oil. (2) It was presumed that the tool wear decreases and the tool life is improved by the lubrication effect of the synthetic lubrication additive, mineral oil and sulfuric EP additive contained in the water-miscible cutting fluid, and also by the cooling effect.

A Practical Evaluation Approach to Form Deviation for Surface of Revolution Based on Discrete Point Coordinate Data

This paper proposes a practical evaluation approach to form deviation for surface of revolution based on discrete point coordinate data. An approximate curve composed of circular arc segments decided from an optimal interpolation process is accepted for computing the form deviation at measured points instead of the generating line of the surface to be inspected. This operation significantly simplifies the algorithm and improves the efficiency in the evaluation calculation. At the same time, it is also guaranteed that the difference of both form deviation values relative to the approximate surface or to the original surface is restricted within the specified accuracy in the circular arc interpolation operation. The effectiveness and efficiency of the approach are verified through a practical example of the surface of revolution with a generating line in the form of cubic Bézier curve.

Optimal Generation of Cutter Path in the Form of Polar Coordinate for NC Machining of Noncircular Contours

This paper proposes an optimal interpolation approach to generate cutter paths in the form of polar coordinate for machining noncircular contours. The cutter path obtained with the approach consists of a series of Archimedes’ spiral segments and the number of segments is the fewest under the condition that the interpolation error completely satisfies the specified limit value. It can be also evidenced that the profile error of the machined contour due to the cutter path is perfectly controlled within the specified interpolation accuracy limit. The result of applying the approach to the contour machining of a disc cam sufficiently illustrates the effectiveness of the proposed approach.