Study Of The Key Technology On Crankshaft Locating Basis Based On Optimum Blank Matching

In the crankshaft processing technology, the processing precision of the crankshaft main base central hole has a direct impart on the crankshaft follow-up machining. If the crankshaft central hole processing is imprecise, then the follow-up allowance distribution of the crankshaft is uneven, that will directly lead to poor quality of the crankshaft processing surface and increased dynamic unbalance of the crankshaft and the rejection rate of the crankshaft processing.This paper introduce recently the commonly used processing methods of crankshaft center hole, and analyze the traditional crankshaft center hole processing technology, do some research and exploration for the crucial working operation--base machining(drilling center hole) in crankshaft machining process, put forward a new crankshaft central hole processing methods which based on the optimum blank matching, the method is to make the three-dimensional graphics of blank crankshaft inclusive the three-dimensional graphics of design model, to make the processing allowance of rough crankshaft even, to improve the quality of the crankshaft machining.Divide into two steps to complete the best matching process ,through the rough and fine matching of blank crankshaft to achieve the best blank crankshaft matching, rough matching for blank crankshaft is to make the curved surface of blank crankshaft and the theoretical design curved surface broadly similar to the location in space. Fine matching is to get the best surface matching attitude and the optimum allowance distribution. Crankshaft blank surface is formed by a number of surfaces, so it is difficulty to match crankshaft blank, and the calculated amount of matching is too much. In order to reduce the difficulty and calculation of crankshaft blank matching, when carry out the rough matching of crankshaft blank ,only select the representative local characteristics to rough match; During the next process of fine matching, focus on the main processing site, that is the main journal and the crank arm for fine matching. In the crankshaft blank matching process to create a mathematical model, use the genetic algorithms to solve the mathematical model, judging on the identification for blank crankshaft, the parts which are not satisfied with the processing requirements are scrapped early, while for the parts which meet the processing requirements to automatic self-location machine.Self-location processing is use the information obtained through the optimum matching of crankshaft blank reconstruction model and the design model image, which obtained by the machine vision image, to control the location movement of power head and working table, adjusting the power head or the working table location to adapt to the request of center hole location processing, the final processing central hole of crankshaft to meet the precise requirement. This paper determine the movement configuration of crankshaft self-location machine tool according to the configure characteristics of the multi-axis machine tool movement, and Make preliminary design for the power tool.