To maintain the accuracy of O.D. size, we use an in-process O.D. gauge in cylindrical grinding. In its gauge system, the wheel head stops grinding and returns to the start position when it recognizes the zero point signal output by the O.D. gauge. Even if we use the in-process O.D. gauge and when we measure the O.D. size after grinding, however, the size of the workpiece tends to be smaller due to the grinding heat. The temperature of the workpiece after grinding is higher than that of the reference workpiece set as the zero point. It is necessary to monitor thermal deformation of the workpiece after grinding to improve the size accuracy. We have developed a technique for minimizing size errors. In this new technique, using the signal obtained from the AE sensor, we can estimate the actual amount of thermal deformation of the workpiece after grinding, and make a size adjustment reflecting the estimated position of the zero point. Finally, we can acquire the actual O.D. size, even if the grinding heat shrinks.

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It is necessary to control the residual stock amount for highly precise cylindrical grinding. Here, we introduce a technique for measuring the residual stock amount. In this new technique, it is necessary to measure the system and contact stiffness between the grinding wheel and a workpiece before grinding and the grinding force during the grinding cycle. The residual stock amount can be calculated by the system and contact stiffness and the grinding force. It originates in the system stiffness and the contact stiffness. We propose a new technique for measuring the system and contact stiffness. We verified the system and contact stiffness data determined using the new measuring technique in comparison with data obtained using the standard measurement technique. This new measurement technique can be executed in a short time automatically on a cylindrical grinding machine.

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This study examined the effects of laser heat treatment of work material on chip breakablity and surface roughness in turning of carbon steel. A direct diode laser (DDL) was installed on the tool post of a CNC lathe, and the laser was used to linearly irradiate the cylindrical workpiece surface in the longitudinal direction prior to the turning test. P30 grade carbide and TiC-Al₂O₃ ceramic tools were chosen and a breaker piece was used in each insert. In the case of ordinary turning without laser heat treatment, the chip was broken at a high feed rate and low cutting speed. Laser heat treatment, however, made it possible to break chips over a wide range of cutting conditions because the work material was partially embrittled. The surface roughness was somewhat reduced due to the removal of adhesive objects on the cutting edge by intermittent cutting of selective hard-brittle materials.

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The internal magnetic field-assisted machining process can be applied to inside surface finishing, such as in various types of long slender tubes and bent tubes, as lines of magnetic force can easily penetrate nonmagnetic materials. The behaviors of the magnetic tool are greatly influenced by the magnetizing characteristics of the magnetic tool material, the type of magnetic field, and its strength. This report describes a new internal magnetic field-assisted finishing process that uses both an alternating magnetic field and magnetic pin tools. From the experimental and analytical results, the relationship was examined between the magnetizing characteristics of the magnetic pin tool and the machining behaviors of the magnetic pin tools. Moreover, a comparative study of the behaviors of the magnet pin tools produced with SUS304 magnetic pin tool and a rare earth permanent magnet was performed.

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Full-mouth debridement and cleaning of dental biofilm are required for removal of the pathogens associated with periodontal disease. Then, smoothing of the dentin root surfaces (root planing) that have lost periodontal attachment is the most effective method to stop inflammation and recover the periodontal attachment. These procedures are currently performed using steel curette-type scalers with a cutting edge. However, the direction of curettage must be restricted when the tip of the scaler is manipulated in a periodontal pocket that contains pathogenic biofilm. The authors have developed a file-type scaler electroplated with diamond abrasive to the tip. This scaler can be manipulated in arbitrary directions for curettage. In this study, the curettage performance of the electroplated diamond scaler was evaluated in comparison with the standard curette style scaler.

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