Hydrostatic guideways have various applications in precision machine tools due to their high motion accuracy. The analysis of motion straightness in hydrostatic guideways is generally ignoring the external load on the...Hydrostatic guideways have various applications in precision machine tools due to their high motion accuracy. The analysis of motion straightness in hydrostatic guideways is generally ignoring the external load on the slider. A variation force also exists, caused by the different working positions, together with the dead load of the slider and that of other auxiliary devices. The effect of working position on vertical motion straightness is investigated based on the equivalent static model, considering the error averaging effort of pressured oil film in open hydrostatic guideways. Open hydrostatic guideways in LGF1000 are analyzed with this approach. The theoretical results show that the slider has maximum vertical motion straightness when the working position is closer the guiderail of Y axis. The vertical motion straightness reaches a minimum value as the working position is located at the center of the two guiderails on the Y axis. The difference between the maximum and minimum vertical motion straightness is 34.7%. The smaller vertical motion straightness is attributed to the smaller spacing of the two pads centers, along the Y direction. The experimental results show that the vertical motion straightness is 4.15 μm/1200 mm, when the working position is located in the middle of the Xbeam, and 5.08 pro/1200 mm, when the working position is approaching the Y guiderails, denoting an increase of 18.3%. The changing trends of the measured results validate the correctness of the theoretical model. The research work can be used to reveal the variation law of accuracy of the open hydrostatic guideways, under different working positions, to predict the machining precision, and provides the basis for an error compensation strategy for gantry type grinding machines.展开更多
The Eighth Five-year Plan period wasa fast growing period for Jiangsu’sforeign economic and technical co-operation. Guided by the policy of seizingopportunities, expanding the opening driveand promoting development, ...The Eighth Five-year Plan period wasa fast growing period for Jiangsu’sforeign economic and technical co-operation. Guided by the policy of seizingopportunities, expanding the opening driveand promoting development, all the staff atthe provincial foreign economic front madeevery effort to fulfill the goal of the sus-tained, fast and healthy development in for-展开更多
The 1990s is a key historical decade in the process of China’s on-going modernization drive.When reviewing the overall picture of the socio-economic trend and S&T development around the world during the last two ...The 1990s is a key historical decade in the process of China’s on-going modernization drive.When reviewing the overall picture of the socio-economic trend and S&T development around the world during the last two decades,we may reach the conclusion that a new technological revolution is taking shape.For both the developed and the developing countries,challenges and opportunities are close at hand.In the Decision to Speed up China’s S&T Progress Jointly Issued by the CPC Central Committee and the State Council.a developmen-展开更多
“Open community” has aroused widespread concern and research. This paper focuses on the system analysis research of the problem that based on statistics including the regression equation fitting function and mathema...“Open community” has aroused widespread concern and research. This paper focuses on the system analysis research of the problem that based on statistics including the regression equation fitting function and mathematical theory, combined with the actual effect of camera measurement method, Prim’s algorithm and neural network to “Open community” and the applicable conditions. Research results show that with the increasing number of roads within the district, the benefit time gradually increased, but each type of district capacity is different.展开更多
基金Supported by National Natural Science Foundation of China(Grant No.51275395)National Science and Technology Major Project of Ministry of Science and Technology of China(Grant No.2012ZX04002–091)the Scientific Research Foundation of Shandong University of Science and Technology for Recruited Talents,China(Grant No.2014RCJJ022)
文摘Hydrostatic guideways have various applications in precision machine tools due to their high motion accuracy. The analysis of motion straightness in hydrostatic guideways is generally ignoring the external load on the slider. A variation force also exists, caused by the different working positions, together with the dead load of the slider and that of other auxiliary devices. The effect of working position on vertical motion straightness is investigated based on the equivalent static model, considering the error averaging effort of pressured oil film in open hydrostatic guideways. Open hydrostatic guideways in LGF1000 are analyzed with this approach. The theoretical results show that the slider has maximum vertical motion straightness when the working position is closer the guiderail of Y axis. The vertical motion straightness reaches a minimum value as the working position is located at the center of the two guiderails on the Y axis. The difference between the maximum and minimum vertical motion straightness is 34.7%. The smaller vertical motion straightness is attributed to the smaller spacing of the two pads centers, along the Y direction. The experimental results show that the vertical motion straightness is 4.15 μm/1200 mm, when the working position is located in the middle of the Xbeam, and 5.08 pro/1200 mm, when the working position is approaching the Y guiderails, denoting an increase of 18.3%. The changing trends of the measured results validate the correctness of the theoretical model. The research work can be used to reveal the variation law of accuracy of the open hydrostatic guideways, under different working positions, to predict the machining precision, and provides the basis for an error compensation strategy for gantry type grinding machines.
文摘The Eighth Five-year Plan period wasa fast growing period for Jiangsu’sforeign economic and technical co-operation. Guided by the policy of seizingopportunities, expanding the opening driveand promoting development, all the staff atthe provincial foreign economic front madeevery effort to fulfill the goal of the sus-tained, fast and healthy development in for-
文摘The 1990s is a key historical decade in the process of China’s on-going modernization drive.When reviewing the overall picture of the socio-economic trend and S&T development around the world during the last two decades,we may reach the conclusion that a new technological revolution is taking shape.For both the developed and the developing countries,challenges and opportunities are close at hand.In the Decision to Speed up China’s S&T Progress Jointly Issued by the CPC Central Committee and the State Council.a developmen-
文摘“Open community” has aroused widespread concern and research. This paper focuses on the system analysis research of the problem that based on statistics including the regression equation fitting function and mathematical theory, combined with the actual effect of camera measurement method, Prim’s algorithm and neural network to “Open community” and the applicable conditions. Research results show that with the increasing number of roads within the district, the benefit time gradually increased, but each type of district capacity is different.
