Refine Search

New Search

Results: 12,479

(searched for: publisher_group_id:375)
Save to Scifeed
Page of 250
Articles per Page
by
Show export options
  Select all
Kunihito Kato, Masashi Nishiyama, Ryosuke Kawanishi, Hirokatsu Kataoka
Journal of the Japan Society for Precision Engineering, Volume 87, pp 783-786; https://doi.org/10.2493/jjspe.87.783

Junichi Ikeno, Masaki Ito, Junichi Uesaka, Atsushi Kojima, Ichiro Nishimura, Nobuhide Ito, Weimin Lin
Journal of the Japan Society for Precision Engineering, Volume 87, pp 787-791; https://doi.org/10.2493/jjspe.87.787

Koki Nozomuto, Hideki Aoyama, Yukio Mori
Journal of the Japan Society for Precision Engineering, Volume 87, pp 821-826; https://doi.org/10.2493/jjspe.87.821

Abstract:
Since wrinkle-texture can give different impressions and functions to a product, it has the important design role. The current method to design wrinkle-texture is to copy surface-patterns of natural objects such as leather and a pear. However, it is difficult to design various patterns that satisfy the sensibility of designers and customers because the copied wrinkles are limited in diversity. In addition, since designed wrinkle-texture sizes are small as compared to the target surface of a products, same patterns must be repeated to obtain a large wrinkle-texture area. For these problems, this study has developed three systems: a system to easily and promptly design wrinkle-textures based on KANSEI of designers and customers, a system to design wrinkle-textures by fusing wrinkle-textures having different impressions, and a system to design large size wrinkle-textures by comfortably connecting small size wrinkle-textures.
Osamu Sato, Kazuya Matsuzaki, Takahiro Michimoto, Hideo Takino
Journal of the Japan Society for Precision Engineering, Volume 87, pp 779-782; https://doi.org/10.2493/jjspe.87.779

Shodai Aoyama, Tatsuya Imai, Tohru Takahashi, Atsushi Matsubara, Daisuke Kono
Journal of the Japan Society for Precision Engineering, Volume 87, pp 834-839; https://doi.org/10.2493/jjspe.87.834

Abstract:
When performing finite element analysis of mechanical devices, it is difficult to calculate including the linear motion guide because the analysis cost is huge. In this paper, two finite element analysis models considering the rigidity of the linear motion guide are proposed. One is an iterative calculation method that repeats the load distribution theory and FEM. The other is a direct calculation method using a non-linear spring that follows the rigidity obtained by load distribution analysis. As a result of verification experiments using a uniaxial table, it is confirmed that both analysis models can accurately predict the deformation of the table. In addition, the ratio of displacement derived from the linear motion guide is estimated from the comparison between the experiment and the analysis using the machining tools.
Akira Ueno, Honghu Guo, Ryota Moritoyo, Akihiro Takezawa, Mitsuru Kitamura
Journal of the Japan Society for Precision Engineering, Volume 87, pp 827-833; https://doi.org/10.2493/jjspe.87.827

Abstract:
In recent years, additive manufacturing (AM) has been used in industrial products for fabricating complex geometry. On the other hand, topological optimization is a suitable method for designing complex geometry. Therefore, there are many studies of combining AM and topological optimization these days. As a variant of topological optimization, density optimization of lattice structure is recently studied. The lattice structure is a characteristic one that includes void inside structure fabricated by AM. The designed model by topological optimization should be modified for a suitable structure for AM process. This research tried to use lattice volume fraction optimization for an industrial AM product. Firstly, we have developed a method of designing the lattice unit cell that its effective thermal conductivity is controlled by design variables. Effective thermal conductivity of lattice is calculated by homogenization method and finite element method (FEM). It was confirmed that the effective thermal conductivity changes depending on the size of the internal pores. Next, we consider the minimization problem of the surface temperature of the target domain. By lattice volume fraction optimization, the uniformity of the surface temperature of the target domain was improved. In addition, we fabricated test pieces of lattice and 3D example model by using selective laser melting additive manufacturing. The results showed that the error between the measurement and the analysis using the test piece was sufficiently small.
Yuta Mori, Takeshi Hatsuzawa
Journal of the Japan Society for Precision Engineering, Volume 87, pp 840-844; https://doi.org/10.2493/jjspe.87.840

Abstract:
Distribution measurement of eyelid pressure is an important technology for diagnosis and treatment on corneal disorders, dry eyes etc. In the previous report, we have demonstrated the abrasive test of plane sucrose film samples, and experimentally evaluated thickness reduction characteristics of sucrose films. Although it showed sufficient potential of sucrose films for the distribution measurement of eyelid pressure, it was limited only to plane surface. In this study, we fabricated spherical lenses using melted sucrose with molding dies, and performed its abrasive test using a newly designed abrasive tester. The thickness reduction of sucrose lenses was evaluated by an image comparison of the lenses before and after the test. Experimental results proved the spherical sucrose films with the image comparison can be applied for the distribution measurement of eyelid pressure.
金沢大学理工学域機械工学類生産加工システム・精密加工研究室
Journal of the Japan Society for Precision Engineering, Volume 87, pp 813-814; https://doi.org/10.2493/jjspe.87.813

Unkai Sato, Hideki Kawakubo
Journal of the Japan Society for Precision Engineering, Volume 87, pp 772-778; https://doi.org/10.2493/jjspe.87.772

Abstract:
This paper discusses the influence of Na2SO4-electrolytic oxidizing water (hereinafter it is referred as EO water) on the polished surface of oxygen free copper. Firstly, the Impact elucidation experiment against the polished surface of oxygen free copper, using Na2SO4 EO water and H2SO4 solution, and with or without ultrasonic, was carried out. The results showed the etching marks when immersed in Na2SO4 EO water are remarkable, compared to the H2SO4 solution, and there was almost no difference with or without the ultrasound. Next, the Impact elucidation experiment against the polished surface of oxygen free copper was also conducted after the heat treatment, was carried out. The results showed on the surface of the test piece after the immersion treatment, protrusions are generated when immersed into H2SO4 solution, but almost no protrusions are generated when immersed into the N2SO4 EO water. Lastly, the cause of protrusions was clarified by the verification experiments. By this study, we received the suggestion that a surface of oxygen free copper with higher accuracy can be obtained.
Tohru Takahashi, Ryuichi Yamakoshi, Tomofumi Ohashi, Shoji Noguchi
Journal of the Japan Society for Precision Engineering, Volume 87, pp 765-771; https://doi.org/10.2493/jjspe.87.765

Abstract:
A linear motion ball guide (LMBG) has infinitesimal attitude change generated by rolling element circulation, called "waving." The waving is one of the technical issues in applying LMBG system for the ultra-precision field. Especially on the ultra-precision machine tool, the waving causes a stripe-shaped cyclic processing error on the processed surface, and this error degrades the surface quality of the workpiece. Several studies have been conducted to solve the waving problem. The first report has clarified the waving generation mechanism and the waving minimize method. The second report has clarified the influence of the rigidness of the table plate on the waving. This report has also shown the design guideline of the table plate to achieve the desired magnitude of waving. The third report has analyzed the influence of misalignments due to the machining accuracy of each part to the waving. From the analyses, although horizontal alignment influences the magnitude of waving, misalignments other four directions hardly influence the waving. This paper reported experimental results to verify these analyses. As a result, experimental results as analyses were obtained; only horizontal misalignment significantly affected waving. The theory proposed in the third report has been therefore verified.
有明高専創造工学科メカニクスコース「精密加工・モノづくり研究室」
Journal of the Japan Society for Precision Engineering, Volume 87, pp 748-749; https://doi.org/10.2493/jjspe.87.748

Atsushi Taguchi
Journal of the Japan Society for Precision Engineering, Volume 87, pp 725-729; https://doi.org/10.2493/jjspe.87.725

Yui Takaki Shirato, Wataru Ohnishi, Hiroshi Fujimoto, Yoichi Hori, Koichi Sakata, Atsushi Hara
Journal of the Japan Society for Precision Engineering, Volume 87, pp 759-764; https://doi.org/10.2493/jjspe.87.759

Abstract:
Pneumatic cylinders have advantages of light weight, low heat generation, and low cost, making them potentially suit- able for coarse motion stages in large positioning systems. However, the high-precision and high-speed positioning with the pneumatic driving system has many challenges. One challenge is the dead zone, which is one of the nonlinear characteristics. The conventional dead zone compensation method using the inverse model of the valve cannot cope with the dead zone variation caused by temperature and pressure fluctuation. Furthermore, the effect of nonlinearity is strong at small flow rates near the dead zone, making flow control difficult. To solve these problems, we proposed a twin-drive system using two valves, which can control the sum and difference of mass flow rates (total flow rate and leakage). By setting the leakage of the mass flow rate, the system can be driven at an operating point with high linearity, which enables precise flow control. The interference between the two valves was decoupled by the Hadamard matrix. The experimental results show that the mass flow rate difference follows the reference value without being affected by the dead zone compared to the conventional method.
Yusuke Kajihara
Journal of the Japan Society for Precision Engineering, Volume 87, pp 721-724; https://doi.org/10.2493/jjspe.87.721

Tsuyoshi Nagato, Junya Fujimoto, Takuro Ikeda
Journal of the Japan Society for Precision Engineering, Volume 87, pp 676-679; https://doi.org/10.2493/jjspe.87.676

富山県立大学工学部知能ロボット工学科知的センシング工学講座神谷・松本・伊東研究室
Journal of the Japan Society for Precision Engineering, Volume 87, pp 684-685; https://doi.org/10.2493/jjspe.87.684

Tatsuya Imai, Shoji Noguchi
Journal of the Japan Society for Precision Engineering, Volume 87, pp 704-709; https://doi.org/10.2493/jjspe.87.704

Abstract:
In the previous report, we explained the formulation of dynamic simulation by applying the translational system / rotating system model in vibration theory to the load distribution theory, which is a static analysis method for linear motion ball guides (LMBG). We also conducted an impulse response test to intentionally excite the three-degree-of-freedom mode of LMBG, and reported the contents of verifying the natural frequency of each mode. In this simulation, the spring constant and torsional spring constant with five degrees of freedom, which affect the dynamic rigidity, are calculated by the load distribution theory, so the natural frequency of each mode can be predicted with any model number. However, there is no effective calculation method for the damping ratio that affects the vibration intensity, and after all, it is necessary to perform a test in advance to identify the damping ratio or to assume a value from past measurement results, which is complete. Therefore, this time, we made a two-row experimental LMBG and conducted an impulse response test. By analyzing the correlation between the damping ratio obtained and various cont act parameters derived from Hertz's contact theory, a mathematical expression of the damping ratio, that is, I tried to build a damping model. In addition, we report the contents of applying this model to the dynamic simulation of LMBG and verifying it with an actual product.
Koichiro Narimatsu, Soichi Ibaraki, Naruhiro Irino
Journal of the Japan Society for Precision Engineering, Volume 87, pp 698-703; https://doi.org/10.2493/jjspe.87.698

Abstract:
Thermal deformation due to a machine tool's internal heat generation or heat exchange with the ambient environment deteriorates machining accuracy. To suppress the thermal displacement, this paper presents a scheme to estimate and then compensate for the thermal deformation on a turning center by using a deep learning neural network model. A critical issue with its practical implementation is its response to temperature sensor failures. If the compensation drives the machine in an abrupt, unpredictable manner when a sensor fails, it may damage the workpiece or the machine. In this paper, a scheme to train the deep learning model is presented such that it becomes more robust against temperature sensor failures. The deep learning model was trained considering the assumed profiles by the temperature sensors in failure. By using a commercial machine tool, the robustness of the thermal displacement prediction model against the sensor failures is experimentally verified.
Shota Matsui, Nobutoshi Ozaki, Toshiki Hirogaki, Eiichi Aoyama
Journal of the Japan Society for Precision Engineering, Volume 87, pp 691-697; https://doi.org/10.2493/jjspe.87.691

Abstract:
In this study, we focused on screw cutting with a thread mill tool based on helical interpolation motion and proposed a novel monitoring method to achieve a high accuracy of screw cutting with a wireless holder system. In the present report, we investigated the influence of pilot hole diameter on the accuracy of machining the screw for three kinds of steel materials, which were JIS S50C (200 HV2 hardness), JIS SKD61 (400 HV2 hardness) and JIS SKD61 (600 HV2 hardness) steels., based on measured cutting force from the wireless holder system. As a result, the proposed monitoring method is effective to estimate the processes and to improve the accuracy of machining screws from various work materials using helical interpolation motion of a thread mill tool.
Shioji Kodama, Tohru Kamii, Takashi Komuro
Journal of the Japan Society for Precision Engineering, Volume 87, pp 647-650; https://doi.org/10.2493/jjspe.87.647

Page of 250
Articles per Page
by
Show export options
  Select all
Back to Top Top