The purpose of this study is to establish a manufacturing education system for a large number of novice and experienced students. In the manufacturing process, it is necessary to learn a sequence of basic operations to operate NC machine tools (loading and editing of the NC program, setting of the tools, and running and stopping). However, a large number of students cannot simultaneously learn how to use the NC operating panel because the operating panel is embedded in the NC machine tool. Therefore, we have developed an NC operating panel simulator for learning the above mentioned basic operation in a limited time. We have also developed a practice problem and solving the problem serves to check whether the basic operations of the developed simulator have been correctly learned. This paper describes the development of the NC operating panel simulator and its actual practical use.

The purpose of this research is to develop a system that can monitor the condition of the cutting process and keep it always in a normal or optimum state, in which the acoustic emission method is used for monitoring. In realizing the development of such a system, it is fundamental and important to evaluate the source of AE during cutting, that is, the cutting phenomenon qualitatively and quantitatively. In this report, after constructing an experimental system composed of AE measurement, cutting force measurement, and high speed camera, we examine the mechanism of cutting phenomenon from each basic data and discuss the findings obtained from the results. Simultaneously, the correspondence between experimental results and cutting simulation is also evaluated.

This paper discusses the assembly variation that may arise when the positioning between two parts is constrained using a hole and a slot to fit over two locators. This method of controlling mating parts is called “positioning”. Two parts positioned using a hole and a slot fitting over two locators may move relative to each other during assembly because of slight clearances between the locator-hole pair, and/or between the locator-slot pair. The relative motion of two parts using this positioning might simply be considered to be small rotations about the locator-hole joint. However, in many cases, equal locator-hole and locator-slot clearances are toleranced, resulting a motion which is more complex than simple translation or rotation. This paper addresses the motion area that is obtained by positioning using a hole, a slot, and two locators. When the assembly is defined with nominal inter-locator distance of L and locator-hole and locator-slot size clearances of 2δ, the motion area of an arbitrary point (X, Y ) is explicitly described. The motion area corresponding to (X, Y ) is all coordinates (x, y) such that x = 2δ {Y/L(sin θ + 1)+ cos θ }, (tan θ = Y/L), y = 2δ (X≦L), y = 2δ (2X/L-1) (X＞L). This paper presents a tolerance analysis application using the above.

For improving automobile fuel efficiency, the internal combustion engines must be required to reduce the friction and wear. Decreasing viscosity of lubricant is effective for it, but the seizure is easy to happen in engines, especially in the plain bearing. Plain bearings of industrial equipment are damaged by the wear, and it is main causes in the failure phenomena. The purpose of this work is to elucidate the wear progression process of plain bearing material in actual sliding environment. The authors have developed new tribometer which can reproduce the sliding condition of actual machines, and carried out wear tests on Al-Sn-Si alloy bearing material. In running-in process, the convex portion of the bearing surface worn out immediately after the start of the test, and a smooth surface was gradually formed. During that process, wear particles containing Fe buried in the plain bearing. Before seizure process, adhesive wear occurred between Al-Sn-Si alloy and S55C immediately after load increase. Thus, microscopic seizure occurred, the friction coefficient and back steel temperature increased, and adhesion area increased. And then, it seems that macroscopic seizure occurs when contact pressure was over the critical pressure. As a result, it was clarified that the wear process under various sliding condition in actual machine can be investigated by the wear tests using the new tribometer.