【正文】 中文 4340 字 出處： Science in China Series E: Technological Sciences February 2020, Volume 50, Issue 1, pp 6980 Study of utilizing differential gear train to achieve hybrid mechanism of mechanical press HE YuPeng1?, ZHAO ShengDun2, ZOU Jun2 amp。 ZHANG ZhiYuan2 1 School of Mechanical Engineering, Nanjing University of Science amp。 Technology, Nanjing 210094, China。 2 School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, China The problems of hybrid input of mechanical press are studied in this paper, with differential gear train as transmission mechanism. It is proposed that “adjustablespeed amplitude” or “differentialspeed ratio” is the important parameters for the hybrid input mechanism. It not only defines the amplitude of the adjustable speed, but also determines the ratio of the power of the servomotor to the power of the conventional motor. The calculating equations of the ratio of transmission in all axes, the power of two motors, and the working load distribution are deduced. The two kinds of driving schemes are put forward that the servomotor and the conventional motor simultaneously drive and the servomotor and the conventional motor separately drive. The calculating results demonstrate that the latter scheme can use much lower power of the servomotor, so this scheme makes manufacture and use cost much lower. The latter scheme proposes a feasible way to apply the hybrid mechanism of mechanical press in practice engineering. mechanical press, hybrid mechanism, differential gear train, adjustablespeed 1 Introduction At present there are many research papers about the hybrid mechanism of mechanical press, and it has bee a hot research topic. The hybrid mechanism is a mechanism with 2degreeof freedom (also called differential speed mechanism), and when two independent motions are input at the same time, the output that can satisfy some motion requirements is obtained through the motion position of the mechanism. The hybrid mechanism is also called controllable mechanism, or hybrid machine. The purpose of research on hybrid mechanism of mechanical press is using conventional motor with big power carrying flywheel to finish stamping work pieces。 and uses ser — vomotor with low power to adjust the slider speed. The advantages of the hybrid mechanism applied in the mechanical press are that it not only can reduce much lower manufacturing cost than servo press, but also has a flexible working velocity of slider[1]. So the mechanical press of hybrid mechanism arouses many researchers’ interest in working on it。 and these studies are mainly focused on the multibar hybrid mechanism. Du and Guo[1, 2] have prehensively discussed the sevenbar hybrid mechanism of mechanical press, including the feasible conditions of position of the linkage mechanism, the slider motion analysis, and the torque and power distribution between the two motors as well as the optimal design. The trajectory planning based on polynomial interpolation is also investigated, and the puter simulation shows that the result is indeed attractive. In addition, Meng[3] has also investigated the kinematical analysis of the sevenbar mechanism, and the optimal design has been pleted based on the minimum power of the servomotor motor, and Meng has proposed that the hybrid mechanism is a research direction of the mechanical press. Tokuz[4] first put forward of the hybrid mechanism and analyzed the velocity synthesis by using the differential gear train. His experiment confirmed the feasibility of his conception. The concepts of the adjustablespeed amplitude and differentialspeed ratio are not mentioned in their works, and the relationship between the velocity variation and the power of the two motors were not clearly given[5― 8]. But these concepts are very important and absolutely necessary for the hybrid mechanism to select the two motors’ power and determine the working load distribution between conventional motor and the servomotor. In refs. [1― 3] they used linkage mechanism to implement the hybrid input of mechanical press. The method is very plex because the change of the length and position of the each bar in linkage mechanism will have an effect on the motion of the slide of the mechanical press. So some principal problems are usually ignored in research hybrid mechanism course, and the research results don not always coincide with the practice engineering conditions[9― 11]. The gear differential train has two freedoms, and the ratios of transmission between arbitrary two axes are a constant. In order to simplify the mechanical model and make the problems much projected, the differential gear train is used as transmission mechanism to study the hybrid problems of the me