For the purpose of analyzing the torsional vibration caused by the gravitational unbalance torque arisen in a spindle system when it is machining heavy work piece,a 10-DOF lumped parameter model was made for the machi...For the purpose of analyzing the torsional vibration caused by the gravitational unbalance torque arisen in a spindle system when it is machining heavy work piece,a 10-DOF lumped parameter model was made for the machine tool spindle system with geared transmission.By using the elementary method and Runge-Kutta method in Matlab,the eigenvalue problem was solved and the pure torsional vibration responses were obtained and examined.The results show that the spindle system cannot operate in the desired constant rotating speed as far as the gravitational unbalance torque is engaged,so it may cause bad effect on machining accuracy.And the torsional vibration increases infinitely near the resonant frequencies,so the spindle system cannot operate normally during these spindle speed ranges.展开更多
Noticing in recent years that the world is running out of mineral resources, the price of engineering materials will continually rise in the future, the percentage of the cost of manufactured part that is due to the c...Noticing in recent years that the world is running out of mineral resources, the price of engineering materials will continually rise in the future, the percentage of the cost of manufactured part that is due to the cost of materials is also rising. The amount of material must be removed away to produce the final product should be minimized, excess stock will increase not only the material cost, but also processing cost, fixture cost, tooling cost, and increases machine cycle times. This paper proposed a variant CAPP system for rotational parts based on the concept of group technology, this system accepts part features characteristics code number as an input and specify operation details for manufacturing route with the suitable primary processes required to produce the blank work piece as an output.展开更多
In this paper, we present the double Beta spline curved surface which is controlled by double parameters including the algorithm principles, the treatment of boundary conditions, the alternation of projection, the alg...In this paper, we present the double Beta spline curved surface which is controlled by double parameters including the algorithm principles, the treatment of boundary conditions, the alternation of projection, the algorithms of elimination hiddle line, the process to display and the primiples to produce the shaded curved surface. Based on all the above, a freedom surface modeling system (FSMS) is designed and some examples developed on FSMS are verified and analyzed.展开更多
Japanese Prime Minister Yasuhiro Nakasone ended his twohectic days of trade talk withUS President Ronald Reagan andother senior officials inWashington and returned toTokyo on May 4.China’s top leader Deng Xiao-ping t...Japanese Prime Minister Yasuhiro Nakasone ended his twohectic days of trade talk withUS President Ronald Reagan andother senior officials inWashington and returned toTokyo on May 4.China’s top leader Deng Xiao-ping told the Chairman of Japan-China Friendship.AssociationTokuma Utsunomiya on May 5 thatthe Japanese Government shouldlook closely into,and properlyhandle a lawsuit concerning theKokario Dormitory,a piece ofChinese-owned real estate inJapan.展开更多
汉语中常用“横竖”、“贵贱”、“死活”、“高低”、“好歹”等词语来加强语气,表达“无论如何……”,“不管怎样……”的含意;英语中也有类似的短语,根据其着眼点的不同,约可分为以下几种。 A.从代价着眼: 1.at all costs(不惜任何...汉语中常用“横竖”、“贵贱”、“死活”、“高低”、“好歹”等词语来加强语气,表达“无论如何……”,“不管怎样……”的含意;英语中也有类似的短语,根据其着眼点的不同,约可分为以下几种。 A.从代价着眼: 1.at all costs(不惜任何牺牲或代价)展开更多
基金Project(10033135-2009-11) supported by the Korean Ministry of Knowledge Economy (MKE) through HNK. Co,Ltd.
文摘For the purpose of analyzing the torsional vibration caused by the gravitational unbalance torque arisen in a spindle system when it is machining heavy work piece,a 10-DOF lumped parameter model was made for the machine tool spindle system with geared transmission.By using the elementary method and Runge-Kutta method in Matlab,the eigenvalue problem was solved and the pure torsional vibration responses were obtained and examined.The results show that the spindle system cannot operate in the desired constant rotating speed as far as the gravitational unbalance torque is engaged,so it may cause bad effect on machining accuracy.And the torsional vibration increases infinitely near the resonant frequencies,so the spindle system cannot operate normally during these spindle speed ranges.
文摘Noticing in recent years that the world is running out of mineral resources, the price of engineering materials will continually rise in the future, the percentage of the cost of manufactured part that is due to the cost of materials is also rising. The amount of material must be removed away to produce the final product should be minimized, excess stock will increase not only the material cost, but also processing cost, fixture cost, tooling cost, and increases machine cycle times. This paper proposed a variant CAPP system for rotational parts based on the concept of group technology, this system accepts part features characteristics code number as an input and specify operation details for manufacturing route with the suitable primary processes required to produce the blank work piece as an output.
文摘In this paper, we present the double Beta spline curved surface which is controlled by double parameters including the algorithm principles, the treatment of boundary conditions, the alternation of projection, the algorithms of elimination hiddle line, the process to display and the primiples to produce the shaded curved surface. Based on all the above, a freedom surface modeling system (FSMS) is designed and some examples developed on FSMS are verified and analyzed.
文摘Japanese Prime Minister Yasuhiro Nakasone ended his twohectic days of trade talk withUS President Ronald Reagan andother senior officials inWashington and returned toTokyo on May 4.China’s top leader Deng Xiao-ping told the Chairman of Japan-China Friendship.AssociationTokuma Utsunomiya on May 5 thatthe Japanese Government shouldlook closely into,and properlyhandle a lawsuit concerning theKokario Dormitory,a piece ofChinese-owned real estate inJapan.
