Papers by Author: Toshirou Iyama

Abstract: Green manufacturing is important subject. In order to reduce waste disposal cost and environmental load, decreasing machining fluid that contains several chemicals such as oil, extreme pressure agent etc. is demanded. In this investigation, the electric rust preventive machining method system that uses only water as machining fluid have been developed. This paper mentioned about evaluation of recycled water quality. The refined water that is purified with developed water recycle system which is installed reverse osmosis membrane (RO) is too clean to evaluate by normal method till now. Using laser turbidity meter, precise water purification is evaluated precisely. Therefore, it is clarified that RO refined water turbidity (RO1=0.0006, RO2=0.0003) is very low compared with clean tap water (0.1207). So, water recycle system can remove contaminating fine particle from water. It is expected that scratch less ultra precision machining with water is enabled to conduct with high filtration ability.

Abstract: Roughness is important criterion of ground surface. When the surface roughness is demanded to be smooth, it is required to make the grinding conditions optimum. To optimize the grinding conditions, relationship between grinding conditions and ground surface roughness must be known. Therefore, it has been attempted to reveal the effect of grinding conditions on the roughness of ground surface over the years. From previous researches, it becomes possible to estimate the ground surface roughness with statistical grinding theory. However, there are some parameters, such as wheel depth of cut and distribution of abrasive grain, are not factored in the theory. In this paper, fundamental research on cross sectional profile is carried out to consider the relationship between the wheel depth of cut and ground surface roughness.

Abstract: Currently, the machining fluid includes several chemicals such as cutting oil and grinding oil is used for the machining. However, such the machining fluid that is caused enormous disposal cost and environmental load, should reduce using. Therefore, in this investigation, electric rust preventive machining method which uses only water for machining fluid is developed. Because using only water without extreme pressure agents, oil and so on, this method decreases disposal of waste machining fluid. In this paper, the system to remove impurities from a used machining fluid, and to reuse machining fluid is designed. To reproduce water efficiently, the order of arranging the filter is changed. In consequence, it has been efficient when the filtration filter is set up first, and the activated carbon filter is set up in the second. In addition, the reproduction of the water when the supply pressure is 0.75 MPa is verified by using this system. As a result, the water which passed a water recycle system, the impurities such as iron, conductivity, turbidity, colour decreased, and purification of the water is possible for this system. And, 5.2 L/min refined water recycle is achieved.

Abstract: Both form accuracy and smooth surface is required in precision grinding. And the form accuracy and surface roughness are improved year by year. However, the more the surface roughness becomes smoother, the more the grinding marks become remarkable. The grinding mark deteriorates the accuracy of optical parts. It is found that the vibration of grinding wheel is transcribed to the ground surface and forms the waviness named nano-topography. And the nano-topography causes grinding marks. In this study, relationship between the nano-topography on non-axisymmetric aspherical ground surface and grinding condition is analyzed theoretically to control the distribution of nano-topography. As a result, simulation method of nano-topography distribution is developed.

Abstract: A prototype three-dimensional tool oscillation system for finishing metal molds, which can oscillate a tool in a figure-8 motion, has been developed. When such a tool motion is used, the lapping direction alternatively changes and consequently a very smooth surface might be achieved in a relatively short time in the presence of a very fine abrasive compound. The developed tool oscillation system consists of three multilayer piezoelectric transducers. The orientation of the tool motion can be changed in three dimensional space. This paper describes the structure of the tool oscillation system, the driving method of the three piezoelectric transducers for oscillating a tool in a figure-8 motion and the measurement results for the tool motions.

Abstract: For the purpose of investigating the effect of cutting edge truncation on ground surface morphology, several kinds of hard and brittle materials used for optical devices, borosilicate glass, glass quartz, crystal quartz and sapphire, are plunge ground with a SD600 metal-bonded grinding wheel, the cutting edges of which are truncated so as to be aligned with the height level of the grinding wheel working surface, after electrocontact discharge truing and dressing. It is found that an improvement of roughness can be obtained for every material investigated, although the degree of roughness improvement depends on the kind of material. Ductile-mode grinding is most likely to be realized in the case of crystal quartz.