Optimizing the geometric configuration of the tool cutting surface,reducing the resistance in the cutting process and energy consumption,are always a concern.Through the method of bionic design,the directrix function ...Optimizing the geometric configuration of the tool cutting surface,reducing the resistance in the cutting process and energy consumption,are always a concern.Through the method of bionic design,the directrix function of the longitudinal section of the beaver tooth rake face is extracted,and its variable curvature characteristics are analyzed.Based on this,a turning tool with variable curvature directrix configuration rake face is designed.The cutting force experiment and machining surface quality analysis experiment were carried out with the designed tool and the linear directrix configuration rake face tool respectively.The measured data of the variable curvature directrix configuration rake face tool is better than the linear directrix configuration rake face tool and its drag reduction performance of the tool is verified by experiments.Through the analysis of the working rake angle and shear angle of the tool with variable curvature directrix configuration rake face,the relationship between the parameters of the variable curvature directrix function and the working rake angle,and shear angle has been obtained.By the method of finite element simulation analysis,the stress field in the cutting zone of two different configuration tools has been analyzed.It has been found that the tool with variable curvature directrix rake face has a‘bending moment'effect on the tool-chip interface due to its curved surface configuration,and a‘prying'effect at the tool tip.These two effects promote the separation of chips from the workpiece and make the cutting process more forcesaving.The research of this paper will have reference significance for the design and application of the curved surface configuration rake face tool.展开更多
In recent years, the new technology of ultrasonic vibration cutting has been drawing general attention. And great advancement in theory and applications in production of the technology have been achieved. Ultrasonic v...In recent years, the new technology of ultrasonic vibration cutting has been drawing general attention. And great advancement in theory and applications in production of the technology have been achieved. Ultrasonic vibration honing system developed in North China Institute of Technology and Nanjing University of Aeronautics and Astronautics of cast iron cylinder (47×97) and thin cylinder of 20# (86×95) has been successfully applied to productive experiment and the technological effect obtained is ideal. In comparison with ordinary honing, ultrasonic vibration honing possesses apparent characteristics: Firstly, it has high processing precision (precision in size ranks IT6, roughness Ra0.05, circularty and cylindericity in size ranks IT6); Secondly, it has small cutting force and low temperature so that no deformation occurs; Thirdly, it has high efficiency. In this paper, the application of a new technique to honing is introduced, and the ultrasonic honing systems of thin cylinder and cast cylinder which have been successfully manufactured and their applying effect are illustrated. This paper analyzes the cutting principle of ultrasonic honing in terms of cutting motion, grain performance and cutting quantity. The study of this technique starts a new approach to which is efficient higher quality and lower consumption to hole’s precise and superprecise machining. At last,the paper introduce the conclution: Ultrasonic honing sharpens grain, which is favorable for raising cutting efficiency; Ultrasonic vibration honing may increase honing depth and raise cutting efficiency. It may also decrease honing power and system deformation; Undergoing practice we can find that the ultrasonic honing system as above discribed can be extended and applied to production. The system not only can be applied to conventional honing machine, its technology effect as good as high precision machine tool, but also can be applied to develop and study ultrasonic vibrating numbrical controlling honing machine tool which will provide a new type, efficient, high quality low consumption, equipment for working precision hole; Appling the same parament as W40 oilstone bar, under the same condition, is very valuable for product and application. Rough machining and finish machining once time finished, which not only improve location accuracy, but also have a high effiency.The honing system not only can be suitable for honing cast cylinder, but also can be applied for honing engineer ceramics as well as hard, crisp material; The dimension and technology paraments of 47 mm honing system as above discribed, can be suitable for honing the cast cylinder of motorcycle or minicar. And the cylinder diameter can be randomly selected from 45 to 65. The dimension and technology paramagnets of 86 honing system as above discribed,can be applied for honing all kinds of cylinder of light or heavy passenger-cargo vehicle, and the cylinder diameter can be randomly selected from 65 to 100; It is easy to achieve new technology of flat roof honing by applying ultrasonic honing.After the flat roof honing, fuel consumption of engine is 1g/Hp, while conventional engine is 3g/Hp.Life expectancy of engine is prolonged greatly after the cylinder by flat roof honing.展开更多
基金Supported by National Natural Science Foundation of China(Grant No.51975003)。
文摘Optimizing the geometric configuration of the tool cutting surface,reducing the resistance in the cutting process and energy consumption,are always a concern.Through the method of bionic design,the directrix function of the longitudinal section of the beaver tooth rake face is extracted,and its variable curvature characteristics are analyzed.Based on this,a turning tool with variable curvature directrix configuration rake face is designed.The cutting force experiment and machining surface quality analysis experiment were carried out with the designed tool and the linear directrix configuration rake face tool respectively.The measured data of the variable curvature directrix configuration rake face tool is better than the linear directrix configuration rake face tool and its drag reduction performance of the tool is verified by experiments.Through the analysis of the working rake angle and shear angle of the tool with variable curvature directrix configuration rake face,the relationship between the parameters of the variable curvature directrix function and the working rake angle,and shear angle has been obtained.By the method of finite element simulation analysis,the stress field in the cutting zone of two different configuration tools has been analyzed.It has been found that the tool with variable curvature directrix rake face has a‘bending moment'effect on the tool-chip interface due to its curved surface configuration,and a‘prying'effect at the tool tip.These two effects promote the separation of chips from the workpiece and make the cutting process more forcesaving.The research of this paper will have reference significance for the design and application of the curved surface configuration rake face tool.
文摘In recent years, the new technology of ultrasonic vibration cutting has been drawing general attention. And great advancement in theory and applications in production of the technology have been achieved. Ultrasonic vibration honing system developed in North China Institute of Technology and Nanjing University of Aeronautics and Astronautics of cast iron cylinder (47×97) and thin cylinder of 20# (86×95) has been successfully applied to productive experiment and the technological effect obtained is ideal. In comparison with ordinary honing, ultrasonic vibration honing possesses apparent characteristics: Firstly, it has high processing precision (precision in size ranks IT6, roughness Ra0.05, circularty and cylindericity in size ranks IT6); Secondly, it has small cutting force and low temperature so that no deformation occurs; Thirdly, it has high efficiency. In this paper, the application of a new technique to honing is introduced, and the ultrasonic honing systems of thin cylinder and cast cylinder which have been successfully manufactured and their applying effect are illustrated. This paper analyzes the cutting principle of ultrasonic honing in terms of cutting motion, grain performance and cutting quantity. The study of this technique starts a new approach to which is efficient higher quality and lower consumption to hole’s precise and superprecise machining. At last,the paper introduce the conclution: Ultrasonic honing sharpens grain, which is favorable for raising cutting efficiency; Ultrasonic vibration honing may increase honing depth and raise cutting efficiency. It may also decrease honing power and system deformation; Undergoing practice we can find that the ultrasonic honing system as above discribed can be extended and applied to production. The system not only can be applied to conventional honing machine, its technology effect as good as high precision machine tool, but also can be applied to develop and study ultrasonic vibrating numbrical controlling honing machine tool which will provide a new type, efficient, high quality low consumption, equipment for working precision hole; Appling the same parament as W40 oilstone bar, under the same condition, is very valuable for product and application. Rough machining and finish machining once time finished, which not only improve location accuracy, but also have a high effiency.The honing system not only can be suitable for honing cast cylinder, but also can be applied for honing engineer ceramics as well as hard, crisp material; The dimension and technology paraments of 47 mm honing system as above discribed, can be suitable for honing the cast cylinder of motorcycle or minicar. And the cylinder diameter can be randomly selected from 45 to 65. The dimension and technology paramagnets of 86 honing system as above discribed,can be applied for honing all kinds of cylinder of light or heavy passenger-cargo vehicle, and the cylinder diameter can be randomly selected from 65 to 100; It is easy to achieve new technology of flat roof honing by applying ultrasonic honing.After the flat roof honing, fuel consumption of engine is 1g/Hp, while conventional engine is 3g/Hp.Life expectancy of engine is prolonged greatly after the cylinder by flat roof honing.
