Qing Jian Liu

The Research of Straight Bevel Gear Face-Hobbing Method on General Five-Axis Machine Tool

To avoid the influence of column vibration on machining precision, it is necessary to simulate the stiffness characteristics of the columns for CNC grinding machine, and to optimize the structure of the column by using sensitivity method. Based on structural characteristics of the grinding machine and structural characteristics of the columns, a finite element model is established to simulate and calculate the first-four models of the columns. In order to optimize the structure of the column, a sensitivity analysis is made to calculate the sensitivity of natural frequencies and mass of the column to each panel and ribbed plate. Considering a weighting factor and taking integrated natural frequency of the column as an optimization objective, the mass of the column as a constraint, an optimization equation is established. By a quadratic programming method, the parameter optimization of the column is got as follows: the mass decreased by 4%, integrated natural frequency increased by 2%. Dynamic stiffness of the column has been optimized by harmonic response analysis, the results showed that the largest column in the Z resonance peak reduced by 8.44%.

Dynamics Simulation Analysis of Column for NC Bevel Gear Grinder

To avoid the influence of column vibration on machining precision, it is necessary to simulate the stiffness characteristics of the columns for CNC grinding machine, and to optimize the structure of the column by using sensitivity method. Based on structural characteristics of the grinding machine and structural characteristics of the columns, a finite element model is established to simulate and calculate the first-four models of the columns. In order to optimize the structure of the column, a sensitivity analysis is made to calculate the sensitivity of natural frequencies and mass of the column to each panel and ribbed plate. Considering a weighting factor and taking integrated natural frequency of the column as an optimization objective, the mass of the column as a constraint, an optimization equation is established. By a quadratic programming method, the parameter optimization of the column is got as follows: the mass decreased by 4%, integrated natural frequency increased by 2%. Dynamic stiffness of the column has been optimized by harmonic response analysis, the results showed that the largest column in the Z resonance peak reduced by 8.44%.

A Method of Pitch Error Compensation for the Open Numerical Control System

The traditional fixed pitch error compensation method exists some defects, such as sampling points are not comprehensive and the necessary compensation points are easy to miss. Faced with these problems, this paper presented a new pitch error compensation method based on the open numerical control system. With this method, the traditional measurement points were serried, and more pitch error data were measured. Then calculated the error data with the cubic spline interpolation computation method, and the compensation location and value were obtained according to the accuracy requirement. The pitch error compensation was completed when the data inputted into the open numerical control system with a defined format.

An Algorithm and Simulation for the Automatic Welding of Battery Cover

In view of the current welding industry, there is no automated programming tool for the welding path of square battery cover. According to differential geometry theory, the principle of nonlinear error is analyzed. Then a simplified model for nonlinear error is established. Based on these, an efficient algorithm based on nonlinear error is proposed. According to the proposed algorithm, two instantiation of the algorithm are presented. Therefore, the proposed algorithm is simple, reliable, and efficient. It adapts to the requirement of two mainstream spuare battery covers perfectly.

Structural Design and Improvement of Spindle in Five-Axis Wood Engraving Machine

In the wood engraving industry, the double swing motor spindle or the double rotation motor spindle is often used as the spindle of five-axis wood engraving machine to achieve three-dimensional sculpture. However, the rough and motor spindle may interfere with each other during machining. Hence, many small regions of rough cannot be machined. To solve this problem, an anthropomorphic double-swing-head mechanism is designed. Instead of motor spindle, the designed mechanism is used as spindle of five-axis wood engraving machine. The level of automation and machining scope of the machine are improved. The workload of subsequent artificial modification is reduced. Then, the machining efficiency and quality of wood products are enhanced, and their production costs are reduced.

Trapezoidal Thread Processing Method Based on Surface Discretization

In order to realize special trapezoidal thread production more quickly and simply, a new processing method is presented. Based on the shape analysis of the spiral curve, spiral surface discrete algorithm is discussed. Spiral surface is discretized in to numerous tiny straight segments, and consequently the trapezoidal thread machining can be accomplished by just using G01. Simulation and experiment results show that this processing method is feasible and with high production efficiency.

Research on a Type of Program-Controlled Three-Dimensional Vibration Platform

Conventional mechanical vibration platform vibrates not only in the direction of back and forth but also in the direction of up and down. Vibrations in both directions are achieved by two mechanisms, respectively. Three-dimensional vibration cannot be realized. In this paper, the servo motor, the gear drive mechanism, and the parallel four-bar linkage mechanism are combined with the NC system. And a type of program-controlled three-dimensional vibration platform is designed. The platform can vibrate in three directions, such as the directions of up and down, left and right, back and forth. The parametric adjustment of amplitude and frequency in three directions can be realized. The vibration platform is suitable for high-speed and light-load three-dimensional vibration. Compared with the existing mechanical vibration platform, the designed vibration platform overcomes some deficiencies to realize three-dimensional vibration with variable frequency and amplitude.

Compiling Research and Realization of 3D Cutter Radius Compensation Based on PMAC

This text introduces the compiling research and realization of 3D cutter radius compensation based on PMAC in Five-Axis NC Machines. First, the importance of 3D cutter radius compensation to machining programming of complicated curved surface will be talked about. Then we will present the theory and accomplishment of this function. Finally, based on the train of thought, an experiment will be done on Five-Axis NC Machines. As can be seen from the result, the method, simple and right, can manufacture components with multiple-axis tandem that satisfy complicated curve accuracy class.

Inflection Points Processing of Continuous Tiny Line Segments for CNC System High-Speed Machining

Overcut or speed impact exists in high-speed interpolation of consecutive tiny segments. Because the remaining distance of the current segment does not exactly equal to an interpolation cycle required distance. Taking processing accuracy as a precondition, a new inflection point processing method is proposed to solve this problem. With different solutions of different angles, this method realizes the tiny line continuous processing with high processing quality. And this method needs a small amount of calculation with strong real-time. Error analysis is done and it can meet machining accuracy requirements. Now this method has been applied to engineering practice.

Design of Machine Operating Panel Based on CAN Bus for the PC-Based CNC System

Machine operating panel is an important component of controlling machine and the human-computer interaction. As CAN bus has the remote and stable transmission characteristic, the remote IO board is designed. A design of machine operating panel based on CAN bus for the PC-based CNC system is introduced, including the overall architecture design and software design method. This paper focuses on the remote IO board, as well as the practical application in the CNC system of TDNC-H8.