1.

論文(AKAGI収録)

論文(AKAGI収録)
永井, 健一 ; 大佐々, 吉宏 ; 長屋, 幸助 ; 武田, 定彦 ; 谷藤, 克也
出版情報: 日本機械学會論文集. C編.  57  pp.1440-1445,  1991-05-25.  日本機械学会
概要: An analytical method is presented for the bending vibration of a circular dise carrying concentrated masses, introducing a new mode of shape function to the Galerkin method. Deflection of the plate is expressed by a product of the mode shape function along radial direction and the circumferential periodic function. The mode shape function is assumed to be the sum of the product of the trigonometrical function and the finite power series. The coefficients of the power series are found to be satisfied by the boundary condition of the plate. Applying the Galerkin method, the number of sets of differential equation with second-order time functions are reduced. It is found that this method gives good accuracy to the natural frequencies within the small number of terms for unknown time functions 続きを見る
2.

論文(AKAGI収録)

論文(AKAGI収録)
長屋, 幸助 ; 平田, 康夫 ; 鶴見, 豊明 ; 武田, 定彦 ; 永井, 健一 ; 谷藤, 克也
出版情報: 日本機械学會論文集. C編.  57  pp.283-287,  1991-01-25.  日本機械学会
概要: Stresses in elliptical-cross-section coil springs become small as compared to other springs used in practical machines at a certain aspect ratio. This article presents a simplified stress expression for designing the elliptical-cross section coil springs. The stresses obtained by the present design formula are compared with those obtained by numerical methods. It is ascertained that the present formula is applicable to design the elliptical-cross section-coil springs. 続きを見る
3.

論文(AKAGI収録)

論文(AKAGI収録)
長屋, 幸助 ; 武田, 定彦 ; 永井, 健一 ; 佐藤, 淳 ; 杉浦, 光則 ; 佐川, 竜一郎
出版情報: 日本機械学會論文集. C編.  56  pp.1588-1591,  1990-06-25.  日本機械学会
概要: This paper proposes a two-dimensional displacement sensor which is available to detect high speed phenomena such as high frequency vibrations. The sensor consists of a laser, polarisers, a beam splitter, solar cells and clean plates in which an index of double refraction varies in one direction. Since the clean plate as just mentioned has not been produced, this paper applies thin films sandwiched with a magnetic fluid, and the double refraction is generated by using permanent magnet. In this system, the laser beam propagating from the moving body is divided into two beams by a beam splitter, and the divided beams pass through the two clean plates whose refraction axes are in right angles with each other. An intensity of the laser beam after passing through the clean plate is detected by a solar cell. Then the position of each beam is decided by the intensity of the laser beam. Experimental tests have been performed to verify the principle as just mentioned. 続きを見る
4.

論文(AKAGI収録)

論文(AKAGI収録)
永井, 健一 ; 渥美, 全弘 ; 杉山, 晋一 ; 長屋, 幸助 ; 谷藤, 克也 ; 武田, 定彦
出版情報: 日本機械学會論文集. C編.  56  pp.1394-1399,  1990-06-25.  日本機械学会
概要: This paper presents analytical results of non-linear vibrations of a traveling beam levitated by magnetic forces. The problem is modeled as the Euler-Bernoulli beam with a variable cross section supported by non-linear springs. The beam and the springs move on an undulated line. Introducing a new mode shape function which is expressed as the product of the trigonometric function and the power series truncated to the fourth order and utilizing the galerkin procedure, basic equations are reduced to the coupled non-linear equations. The steady state solutions of the beam was obtained using the harmonic balance method. It is found that the non-linear responses show the type of soft-spring, the unsymmetric support of the spring or the unsymetric cross section to the mid-point of the beam show large amplitude vibrations of a rotating motion and that of a translating motion in relatively large frequency range. 続きを見る
5.

論文(AKAGI収録)

論文(AKAGI収録)
長屋, 幸助 ; 武田, 定彦 ; 佐藤, 淳 ; 井開, 重男 ; 関口, 肇 ; 斉藤, 登
出版情報: 日本機械学會論文集. C編.  56  pp.1530-1534,  1990-06-25.  日本機械学会
概要: This paper proposes a thrust bearing lubricated by a magnetic fluid under a magnetic field. The critical pressures of the bearing versus the magnitude of the magnetic flux densities have been investigated experimentally. It is clarified that the critical pressures of the proposed bearing are larger than those of the normal lubricant bearing under high speeds. 続きを見る
6.

論文(AKAGI収録)

論文(AKAGI収録)
永井, 健一 ; 荒井, 徳幸 ; 長屋, 幸助 ; 武田, 定彦
出版情報: 日本機械学會論文集. C編.  55  pp.1941-1947,  1989-08-25.  日本機械学会
概要: An analytical method is presented for free flexural vibrations of a cantilevered beam with a concentrated mass, introducing the new mode shape function to the Galerkin procedure. The mode shape function is expressed with the sum of the product of the trigonometrical function and the finite power series truncated with the fourth order. The trigonometrical function expresses the form of the higher mode of vibration. The coefficients of the power series are determined by solving the homogeneous equations for the boundary conditions of the beam. Applying the Galerkin method, the sets of differential equation in a time function are reduced. It is found that this method gives good accuracy to the natural frequencies and the natural modes of vibration within the limited number of terms for unknown time functions. 続きを見る
7.

論文(AKAGI収録)

論文(AKAGI収録)
武田, 定彦 ; 長屋, 幸助 ; 永井, 健一 ; 井開, 重男
出版情報: 日本機械学會論文集. C編.  55  pp.1616-1621,  1989-07-25.  日本機械学会
概要: This paper presents theoretical and experimental results for the steady state response of a relaxation-suspension system considering the unsymmetrical damping force under periodic excitation. the unsymmetrical damping force has two different values in period of the stroke velocity. In the analysis, exact solutions are obtained by considering the continuity of the response at the boundary in which the damping force varies. Numerical calculations are carried out for various values of the ratio of the damping coefficient. It is found that the reference line of the vibration in the relaxation-suspension system maintains a constant value within the range of the high frequency ratio, while the reference line in the direct-suspension system varies proportionally to the change of frequency ratio. The experimental values agreed fairly well with the theoretical results. 続きを見る
8.

論文(AKAGI収録)

論文(AKAGI収録)
長屋, 幸助 ; 武田, 定彦 ; 井開, 重男 ; 永井, 健一 ; 松本, 康臣 ; 塩野, 二朗
出版情報: 日本機械学會論文集. C編.  55  pp.1353-1356,  1989-06-25.  日本機械学会
概要: This paper proposes an active control damper using an electromagnetic fluid, and presents an expression for obtaining the damping coefficient of the damper. The damping coefficient has been obtained by using the solution of the equation for the electromagnetic fluid which includes both Navier-Stokes' equation and Maxwell's equation. Numerical calculations have been carried out for some sample problems, and the effects of sizes of the damper and the magnetic flux density on the damping coefficients have been clarified. 続きを見る
9.

論文(AKAGI収録)

論文(AKAGI収録)
永井, 健一 ; 長屋, 幸助 ; 武田, 定彦 ; 中村, 欣明
出版情報: 日本機械学會論文集. C編.  55  pp.1301-1306,  1989-06-25.  日本機械学会
概要: Analytical results are presented for nonlinear vibrations of a stretched string connected with a laterally movable end mass at one end. Applying the modified Galerkin method to the basic equations, a set of ordinary differential equations with cubic nonlinearity is obtained. The steady-state response is determined by the harmonic balance method. Numerical calculations are carried out for the various values for the end mass to the string and the geometry of the string. It is found that if the mass of the end mass increases to greater than that of the string, the resonant response in the first mode of vibration can be treated as a linear vibration up to a sufficiently large amplitude. However, the resonant curves in the higher mode of vibration show responses with a strong nonlinearity within a small amplitude. The increment of the cross section area of the string also gives a strong nonlinearity to the response in every mode of vibration. 続きを見る
10.

論文(AKAGI収録)

論文(AKAGI収録)
永井, 健一 ; 笹井, 重俊 ; 長屋, 幸助 ; 武田, 定彦 ; 内山, 茂
出版情報: 日本機械学會論文集. C編.  55  pp.79-83,  1989-01-25.  日本機械学会
概要: This paper presents a method for the error compensation of measuring data in a two-dimensional length measuring device from lack of sufficient stiffness. Introducing the mode shape function which is expressed with the product of the finite power series truncated with fourth order and the trigonometric function to the least square approximation. Applying the method to the test device, the effects of compensation are clarified. It is found that this method gives good results to improve the measuring accuracy with the limited number of terms for unknown coefficients, compared with the approach of the Fourier series. 続きを見る