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論文

論文
神宮, 利夫 ; 根津, 紀久雄 ; 坂本, 賢治
出版情報: 日本機械学會論文集. A編.  55  pp.1669-1673,  1989-07-25.  日本機械学会
概要: application/pdf<br />Journal Article<br />The mechanical components of a ball thrust bearing, constant-velocity universal joint, locker arm of a cam driving a cylinder valve and a ball-type pressure-regulating valve, involve the elements of a sphere and an anvil. These are subjected to impact load. In this paper, we suppose a model with the simplest form of only a sphere and an anvil for these complex components. The sphere and anvil are in contact with each other and rest along the straight line joining their centers. When the free-side end of the anvil undergoes the normal collinear impact by travelling around the bar, the impact load transmitted into the sphere adjacent to the anvil is theoretically analyzed by a motion equation and Hertz's contact theory. It is important to find the particle velocity evoked by the arrival of a stress wave at the end of the anvil which is a point contact with the sphere. This particle speed is an initial velocity as the anvil transmits the load into the sphere. The validity of theoretical analysis is confirmed by comparison with an experiment under the same conditions. 続きを見る
2.

論文

論文
神宮, 利夫 ; 松本, 浩之 ; 根津, 紀久雄 ; 坂本, 賢治
出版情報: 日本機械学會論文集. A編.  54  pp.1931-1936,  1988-10-25.  日本機械学会
概要: application/pdf<br />Journal Article<br />Transducers consisting of a strain gage or accelerometer and piezo-electric sensor are popular instruments used to evaluate dynamic response. Although the observation of transmitted strain by means of the strain gage method assures accuracy, it is not convenient to estimate the dynamic response of materials having a large cross-sectional area. On the other hand, there is little restriction in measuring of dynamic response using an accelerometer since it is small and light. It is easy to fabricate the transducer by applying a piezo-electric sensor. However, except for the strain gage method, the technological issues as to whether these are consistent or accurate for the measurements of dynamic response, particularly the impact load, have not been apparent. In this paper, we distinguish the technological issues which may arise in using such dynamic response transducers for measuring the impact load caused by the collision of two round bars or a sphere and flat plate. 続きを見る
3.

論文

論文
神宮, 利夫 ; 松本, 浩之 ; 根津, 紀久雄 ; 坂本, 賢治
出版情報: 日本機械学會論文集. A編.  53  pp.2331-2335,  1987-12-25.  日本機械学会
概要: application/pdf<br />Journal Article<br />In the collision between the flat surface of solid and of a sphere, it can be considered that a high stress will be occur, since an impact load is applied in a small local contact area. If an impact stress exceeds the yield stress of a material, the local deformation of the contact surface converts from elastic to plastic flow. Therefore, the impact load may be moderated. It is important when formulating the impact load that the effect of the local plastic deformation of the contact surface on the time history of a load due to impact is investigated. On the other hand, it is revealed by Hertz's theory that the relationship between a force and the amount of approach of both solids during impact is nonlinear. If it is postulated as being linear, there is not little what be able to apply it to analyze the dynamic impact problem. In this paper, the effect of the local displacement behavior in the contact process on the impact load is shown by the experiment of a collision between a plate of mild steel and a high hardness steel ball. The impact load is evaluated by a piezo electric plastic transducer. The limitation which the modified approach of Hertz's theory is valid, are distinguished. 続きを見る