Non-rotational Tool Research Articles

6-Axis Control Cutting of Overhanging Grooves by means of Non-rotational Tool with the Application of Ultrasonic Vibrations

6-Axis Control Cutting of Overhanging Grooves by means of Non-rotational Tool with the Application of Ultrasonic Vibrations

Manufacture of Overhanging Sharp Corner by Means of 6-Axis Control Machining with the Application of Ultrasonic Vibrations.

The study proposes a new machining method to create an overhanging sharp corner. Sharp corners on overhanging surfaces are difficult to machine in conventional way or even in 3 to 5-axis EDM especially if the surfaces have different angles. This is due to the limitation of the feed direction and the structure of the electrode wherein it must be symmetrical with the target shape. In present research, we try to machine the sharp corner with overhanging surfaces using the new machining method. The 6-axis control machining is applied to set a non-rotational tool at an arbitrary position with arbitrary attitude against the workpiece. During cutting, the ultrasonic vibration is applied on the cutting edge of the tool, while the tool travels along the feed direction. As the cutting is performed, the 6 axes (X, Y, Z, A, B, and C) move simultaneously, depending on the tool attitude at a certain cutting point. From the experimental results, it is shown that the 6-axis control ultrasonic vibration cutting is capable of producing a sharp corner on overhanging surfaces.

５軸および６軸制御を併用したキャラクタライン加工

5-axis control machining can create workpieces with complicated shape difficult to machine by 3-axis control. Moreover, 6-axis control machining can cope with workpieces impossible to machine by rotational tools since it can control the direction of nonrotational tool. Though 5-axis control machining which uses rotational tools is advantageous in terms of the machining efficiency, the cutting remainings peculiar to the rotational tool take place at the corner part of workpiece shape. On the other hand, 6-axis control machining can machine the corner part, which cannot be removed with the rotational tool, though it has the low machining efficiency. The use of two machining methods together seems to be very effective to improve the machining efficiency. This research investigates the highly efficient and accurate machining method using 6-axis control machining together with 5-axis control one. The algorithm to generate the cutter location data is developed in consideration of the use of 5-axis and 6-axis control machining, and it is implemented to the integrated CAM software for 5-axis and 6-axis control machining. As a result, it is experimentally found that the system enables the effective and accurate machining.

2901 6 軸制御キャラクタライン加工用メインプロセッサの開発

This study deals with the main processor for 6-axis control character line machining. In machining with conventional rotational tools, the cutting remains depending on the tool radius may take place at corner parts. Though machining with small radius tool can remove to some degree, it is difficult to remove completely. Therefore, 6-axis control machining has been studied. This machining uses non-rotational tools, and enables to apply to the shapes impossible to be machined for rotational tools. However, there are many kinds of non-rotational tool, and the tool selection on the basis of the target shapes and cutting way is important. CAM system developed in this study can select a non-rotational tool for the target shape, and can generate tool paths in the consideration of tool interference.

2205 振動切削を利用した 6 軸制御加工・オーバハングした角隅形状の場合

The study proposes a new machining method to create a sharp corner on over-hanged surfaces. Sharp corner on overhanging surfaces are difficult to machine in conventional way or even in 3 to 5-axis EDM machine especially if the surfaces have different angles. In present research, we try to machine the sharp corner using the new machining method. The 6-axis controlled machining using the non-rotational tool with the application of ultrasonic vibration has been applied, since they can set the non-rotational tool in an arbitrary position against the workpiece. From the experimental results, it shows that the 6-axis controlled ultrasonic vibration cutting is capable of producing a sharp corner on overhanging surfaces.

2207 6 軸ヘール加工に対する ISO14649 の適用

We apply ISO14649 CNC data model to machining system utilizing non-rotating tool, and test cutting free surface using this machining system. The application of ISO14649 makes this system to more intelligent and informative than current system using RS-274 (G codes).

312 ヘールおよび多軸用 CAM システムの開発

To produce die/mold consisting of smooth curve surfaces by hale (non-rotating tool) machining, it needs simultaneous six-axes controlled machining center. Therefore, we developed a system of six-axes hale machining and that of creating NC data. We got the following results from the whole system. Firstly, we cut curve surfaces both by five-axes as well as six-axes machining center, evaluated the machined surface and cutter path. Secondly, during cutting we maintained the movement of the tool axis as small as possible so as to improve surface roughness (Ry). Finally, we succeeded to achieve Ry of curve surfaces less than 1μm.

シャープなエッジをもつポケット形状の６軸制御加工

This paper describes the development of a system for pocket shaping with sharp-edged corners by use of a non-rotational cutter and a 6-axis control machining center. With a rotational tool, the remains take place at the pocket corners due to the configuration of tool, therefore, it is usually impossible to create the pocket shape with sharp-edged corners. In regard to the above problem, this paper proposes the new method to remove the remains from the corners and to form the pocket shape without round corners by the nonrotational tool. Thus, the non-rotational cutting tool is designed and a CAM software is developed to realize the proposed method. The sharp-edged corner lines consisting of the intersection of side surfaces of pocket shape are machined by use of the side cutting edge of the non-rotational tool, and the sharp edged bottom lines consisting of the intersection between the side surface and the bottom surface, by use of the top cutting edge after the rough cutting by 5-axis control machining with conventional rotational tools such as end mills. The system is applied to finish two kinds of pocket shape; one is composed of only planes, and the other of sculptured surfaces. As a result, the pocket shapes with sharp-edged corners are created, and the validity of the system is experimentally confirmed.

Development of CAM System for Non-rotating Machining of Curved Surface.

The multiaxis machining technology using a non-rotating cutting tool can produce a well-finished surface with little machining damage or roughness, and can be used to remove the remaining material in a concavity formed by the ball nosed end mill. This technique will extend the machining limits beyond the processing capability of the rotating tool. However, the single-blade non-rotating tool does not have a long life nor a flexibility for cutting various shapes. Therefore, a cylindrical non-rotating tool with long life and multiusability has been developed. This tool machines using a sharp blade having a wide curvature which gets shape by its inclination toward the feed direction. The cylindrical non-rotating tool can precisely machine a wide surface always with a sharp portion of the blade, because it can perform cutting at an arbitrary position on the blade due to spindle axis turn positioning. On the other hand, non-rotating machining with μm-scale cutting depth requires more precise CL data than is necessary with a rotating tool. If such CL data are generated by existing methods, a greatly increased quantity of data results, and more time is required to generate an offset surface. However, the copy simulation CAM method for multiaxis machining has been developed, which makes it possible to calculate highly precise CL data without offset processing. The imaginary stylus of this copy simulation CAM method traces on a surface of the defined shape while it self-determines the distance and course to the defined shape. Therefore, it is easy to determine the necessary tool axis vector for multiaxis machining, and the present method can generate highly precise CL data for non-rotating cutting. Results of machining experiments with this CAM method and the cylindrical non-rotating tool show that (1) it was able to get a good surface with approximate roughness of 2μmRy by smoothing machining, (2) it was able to completely removed material remaining in the concavity formed by a ball-nosed end mill, (3) the non-rotating tool and copy simulation CAM method for multiaxis machining can significantly extend the machining limits.

６軸制御による直交面の角隅加工

This paper describes a new machining concept in the squared corner shaping, making use of the cutting characteristics of non-rotational cutting tools and 6-axis control. Though the 5-axis control machining with conventional rotational tools makes it possible to machine sculptured surfaces efficiently and accurately, some problems still exist in the machining. For example, it is impossible to mill workpieces without round corner. This is due to the usage of rotational tools. The 6-axis control machining with a non-rotational tool allows a variety of machining possibilities. In the study, a new 6-axis CAM system for squared corner shaping was developed to remove the remaining of corner radius after rough cutting with rotational tools. The validity of the system is experimentally confirmed.

A New Grinding Method for Ceramics Using a Biaxially Vibrated Nonrotational Ultrasonic Tool

Summary A new method for grinding ceramics and hard materials by using a non-rotational tool has been developed. In the method a fixed abrasive type grinding tool is vibrated by a complex ultrasonic transducer longitudinally and torsionally at the same time. Experiments showed that the complex ultrasonic vibration keeps grinding force low and stable for a long time in grinding hard ceramics even without rotating the tool. When a diamond grinding tool with a square or triangular bottom is used, this method has a great effect on producing cavities with sharp inner corners of almost zero radius on various hard-to-machine materials.