Method for extremely fine grinding and finishing surface of cam of internal combustion engine camshaft through electrochemical composite oilstone with reverse pulses

Abstract

The invention provides a method for extremely fine grinding and finishing the surface of a cam of an internal combustion engine camshaft through electrochemical composite oilstone with reverse pulses. The method has the following advantages that firstly, the surface of the cam can be directly finished to Ra0.1 micrometer or lower through one step after being coarsely ground, so that mirror finishing is achieved; secondly, compared with grinding at the same roughness level, the productivity can be improved by three times to five times or more, and finishing efficiency is quite high; thirdly, in the finishing process, no grinding force or grinding heat is generated, so that the surface layer is free of metallographic structure changes, work hardening and stress condition changes, and the finished surface layer is high in quality; fourthly, passive film on the metal surface is mainly removed through the oilstone, and therefore loss of the oilstone is much smaller than loss caused by ultra-fine machining; fifthly, sediments and microscopic peaks on the surface of an electrode are dissolved through the reverse pulses, the electrode is finished, and the shape of the electrode is kept; sixthly, the process device is simple and is convenient to operate and maintain.

Description

technical field [0001] The invention relates to a finishing technology for the cam surface of an internal combustion engine. Specifically, the surface finishing of the cam surface of the internal combustion engine is carried out by combining electrochemical action and superfine grinding of oilstone, and at the same time, the reverse pulse has a finishing effect on the electrode. , mainly used for the last finishing process of the cam surface of the internal combustion engine. Background technique [0002] The camshaft is one of the key parts of the diesel engine, it controls the intake, oil supply and exhaust process of the diesel engine, the reliability of the camshaft is directly related to the normal operation of the diesel engine and the safe operation of the locomotive. The vast majority of domestic cam production adopts the process of "milling shape → rough grinding → heat treatment → fine grinding" for cam processing. Since the cam curve is composed of several simple...

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Problems solved by technology

Since the cam curve is composed of several simple or complex curve connections, the cam profile is irregular, resulting in a sharp "jump" of speed and acceleration, and the instantaneous speed of the grinding point, the contact arc length of the grinding wheel and the workpiece, and The polar coordinate position of the grinding point relative to the cam center changes with the shape of the cam curve, which makes the grinding force, elastic deformation of the grinding wheel and workpiece system, and grinding heat constantly change, which can easily cause cam grinding defects - Grinding cracks and burns

Using a cam grinder with a profiler for fine grinding is prone to grinding defects, while using an imported CNC cam grinder is not easy to produce grinding defects, but imported CNC cam grinders are expensive, approaching tens of millions of RMB

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