Papers by Author: Peng Li

Abstract: In this paper, the author constructs a dimensionless nonlinear dynamic model of Vibration cutting system described by nonlinear differential equations. The model is established on the relationship between cutting force and cutting speed and the relationship of cutting depth to the cutting resistance and the time. It is the nonlinear dynamic friction model of vibration cutting considering tool-chip friction. Based on the model and the method of chaotic identification, Lyapunov Exponent, the further research on the vibration cutting produce behavior and its classification are conducted.

Abstract: In this paper, turn the medium of magneto rheological liquid into continuation, and using of the critical Reynolds number determine method of liquid move state and compound with non-Newton fluid, get the conclusion of finished machine abrasive magnetic liquid fluid as laminar fluid, for having no mathematics’ model practical or be fit with the experiment, especially the distribution of shear and velocity stress, In this paper, using of the critical Reynolds number to determine the liquid state of magnetic fluid state, and in determined the fluid state, using non-Newton fluid dynamics and tensor analysis theory and also compound with the double dynamic viscosity model, analysis the abrasive magnetic fluid quality of kinematics shear stress, according to the quality, contracture the dynamic model of abrasive magnetic liquid finished machine, during the interfere, using the double viscosity fluid model, we may get the conclusion, liquid magnetic abrasive, when the shear stress more or less the bend stress, and mark with plasticity viscosity η_p0 , η_pγ which round the work piece center, the velocity distribution as laminar, and also, analysis the flow field mathematics’ model by the finite element, and also going on the numerical simulate for the magnetic fluid velocity field of finished machine.

Abstract: Composite (multiple) bead wire is an important machine for stone-sheet production with efficiency, but it takes up space, with big energy consumption, uneven thickness, and noise. The current study aims at optimal designing a bead saw with energy-, material-saving, and being light in weight under the constraint of the strength, stiffness and stability for the frame. A 140 rope saw, as a prototype and one of the applications, discussion of two main frames were done with the layouts consisting of the driving wheel, guide wheel, and the supporting wheels from a variety of structural Patterns. By comparison between the triangular and rectangular layouts, a conclusion was drawn that under the condition of all other things being equal, rectangular layout is more reasonable; each wire is supposed to be adjusted for the uniformity of tension of the whole wires. The objective function was taken as the sum of the mass expression of each component of the frame with a series of punishing factors. The hollow structure of double columns with guide grooves and special beams were got, achieving design goals.

Abstract: Three forms of model parabolic bulldozing plate were designed and manufactured. Their macroscopic soil-engaging surface directrixes consist of parabolic curve and the cutting angle were 50°, 55°and 60°respectively. The working resistance was measured by a homemade indoor soil bin. The parabolic moldboard model with a cutting angle of 55° has the least working resistance. On this basis, the parametric equations of three kinds of macroscopic soil-engaging surface of parabolic type moldboard were established. The intrinsic geometrical quantities of the macroscopic soil-engaging surfaces, including the first base quantity (E, F, & G) and the second base quantity (L, M, & N), were calculated. Compared with the working resistance test results of the three moldboard models, it is found that there is a specific range of E value in first base quantities and L value in second base quantities which can make the soil-engaging surface to obtain lower resistance. This research provides a reference for the resistance-reducing and energy-saving design of macroscopic soil-engaging surface of moldboard.

Abstract: With its technological development, the CNC embroidery machine rotational speed has increased dramatically. Consequent vibration and noise increase the disconnection rate in the embroidery process and affect the embroidery quality and production efficiency. To solve such problem, by analyzing the vibration causes and comparing the different characteristics of the Timoshenko beam and the Euler-Benouli simply supported beam, the current study indicated the limitation of the traditional vibration analysis method---the widely-used Euler-Bernouli simple beam theory, and constructed a vibration model based on the Timoshenko beam theory. Then a finite element model of the embroidery machine beam was built S and the corresponding experiment were done. Results from the constructed mechanical, mathematical model, and the ANSYS finite element model were compared. It has been verified that the constructed models are consistent with experiment results and that vibration models are constructed reasonably and feasibly. According to these models, the key parameters affecting the beam vibration are identified to work out more accurate and effective structure optimization design and prediction.

Abstract: By analyzing factors affecting the accuracy of boring process on the precision boring machine, the article aims at putting forward a method of improving the accuracy of boring process by means of installing polymer elastic shock absorbers on unilateral boring tools. In addition, the situation of non-linear radial forced vibration is formulated by a dynamic model of second-order differential equation. Based on the model, vibration prevention principles of unilateral boring tools have been discussed and systematic parameters have been optimized for enhancement of the boring process accuracy.

Abstract: Virtual assembly plays an important part in virtual fabrication. It can be used to verify whether the design is correctly performed, modify models and display assembly, and optimize the process. This paper introduced the concept of morphological analysis by matrix, and established morphological matrix with the code of feature of the posture of the parts for feasible assembly of mechanical product. Secondly, using 6-point location principle, analyzed locating methods of zipper-head, taken as an example, from generality to specialty. In feeding part, it described the system in virtual assembly by matrix. Finally, Pro/E was used to model and simulate the procedure of the assembling.