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This study describes the programming of cutter location based on a constant feed-speed vector at the cutting point with a ball nose end-mill tool by a Five-axis Machining Center. In the present paper, we proposed a new programming method to maintain both feed-speed amplitude and direction at the cutting point using rotational and linear axes controlling. First of all, we focused on generating a hemispherical surface with a ball nose end-mill, and investigated its surface roughness and its profile error. As a result, it can be seen that this method is effective to obtain a fine machined surface roughness and to avoid the influence of linear motion errors on the machined profile at the normal direction to the feed-speed vector.

The inclusion of the application of the double ball bar (DBB) measurement to the accuracy calibration of five-axis machine tools into the revision of ISO standards is currently under the discussion. This paper presents the modified DBB measurement device, referred to as “DBB5” in our study, where master balls are supported from the 45°direction to the spindle axis. It can perform all the circular tests on XY, YZ, and ZX planes without changing the setup. This paper first presents the classification of motion error components of a five-aixs machine tool into location and component errors. Experimental application examples of the DBB5 to the calibration of location and component errors assciated with rotary axes on a five-axis machine tool are then presented.

This paper deals with a decision method of cutting conditions and tool life estimation method for end-milling processes of plain carbon steel. Basic cutting conditions for side cutting of a step, one of the most basic milling processes, are chosen from the database given by a cutting tool manufacturer. These data are transformed for individual milling processes, e.g. trochoidal grooving, spiral hole enlarging, and corner milling, such that constant cutting force is kept by using feedforward control. Cutting tests were conducted for the workpiece composed of various cutting features, and it was clarified that adequate cutting conditions and adequate tool life are simply decided using by this method.

This study describes the machining of the fine surfaces with a ball nose end-mill tool by a five-axis controlled machining center. In the present paper, we demonstrate that it is effective to maintain a constant contact angle between an end-mill ball nose and a work surface in machining in order to obtain the fine machined surface because this makes it possible to avoid an irregular luster (striped pattern) caused by a profile error of the ball nose on the machined surface. Moreover, it can be seen that the surface roughness (i.e., convexities and concavities) along the tool feed direction can not be overlooked in trying to obtain the fine machined surface such as a mirror surface. As a result, a new method is proposed to determine the optimum cutting condition to achieve the minimum cutting time considering the surface roughness along the pick direction and the feed direction under a constant surface roughness.

This paper describes a CAM system of drilling for Printed Wiring Boards (PWBs). We focused on drilled hole wall quality in addition to machining efficiency. The drill and PWB temperature in drilling was monitored using thermography, because the temperature had a relation to surface roughness of drilled hole wall. The various tool paths were evaluated in order to improve drilling efficiency with sufficient hole quality. As a results, we could have a suggestion of tool path for good quality of drilled hole wall.

This paper describes on high accuracy contour grinding. We focused on problems in the current CAM systems in order to improve the machining accuracy and the quality of ground surface. The changes of curvature in workpiece profile were attracted attention because the ground workpiece profile changes with tool path and grinding force. Therefore, the grinding tests with monitoring the grinding force were carried out for three type models with different variety of curvature. The workpiece profile after grinding was evaluated by reflected light images test. As a result, considering the responsibility of machine tool, it was clarified that the smooth-continuation model shows the best quality of ground surface.

This study describes to finish the curved surfaces in hardened steels (JIS: SKD11, etc.) with (Al, Ti) N-coated ball nose end-mill. Two kinds of cutter locations are used; scanning line cutting and contour line cutting, for finishing the curved surface of hardened steel. In the present paper, the cylindrical surfaces machined by a ball nose end-mill are investigated. As a result, in scanning line machining, an irregular luster (striped pattern) peculiar to the machining work surface was caused by a profile error of ball nose. In addition, a new method was also proposed to estimate the peculiar striped pattern which could be judged from observation of the machined surface using Makyoh-topographic images.

This paper describes the mechanism of cutting temperature rise in micro drilling on Printed Wiring Boards (PWBs), which affects the micro-drilled hole wall quality. The drill temperature monitored by a thermography was evaluated in drilling. Moreover, we investigated the influence of drill workload, which was calculated with cutting force measured by a dynamometer, on the drill temperature. The following conclusions were reached: (1) The drill temperature tends to increase with the drill workload caused by frictional torque between hole wall and the land or margin of drill. (2) The frictional torque increases with the spring back of drilled hole wall in drilling. The spring back of drilled hole wall increases with the outer corner wear of drill cutting edge in drilling. (3) The reduction of the workload by the friction seems to be effective in order to obtain the high quality micro-drilled hole wall.