QUANZHOU YISHENG MACHINERY CO.,LTD Automechanika
The crankshaft is a point S-shaped connection, which is driven by the piston connecting rod to move up and down to drive the crankshaft to twist and rotate, thereby converting the reciprocating motion of the piston into the rotational motion of the crankshaft, and the average conversion of the original piston into the rotation of the crankshaft , So as to output engine power.
The camshaft is a shaft with protrusions on it. The protrusions are used to push the valves. The Engine Camshaft For Mercedes Benz sets the intake and exhaust valves of the cylinder to control the opening and closing of the valves to drive the valves.
Crankshafts and camshafts are important moving parts of the engine. Due to the special structure of the workpiece and the large and uneven cutting amount, the workpiece is subject to large forces and is easy to bend and deform, so the machining accuracy is difficult to guarantee, which affects the quality of subsequent processing, and there is also a quantity of equipment Many, many people, low efficiency, high cost and other issues.
First, the development of camshaft rough machining
The main journals of early camshafts generally used single or multi-tool Ordinary lathes are used for rough machining, and cams are generally completed by mechanical model lathes for single-blade or multi-blade profiling turning. Single-tool turning efficiency is low; multi-tool turning is difficult to ensure the quality of parts, and after rough turning, processes such as straightening and rough grinding must be arranged, resulting in low production efficiency.
Multi-tool turning and profiling turning have large forces during cutting, and the workpiece is prone to bending deformation and vibration, low tool life, frequent tooling, and high defect rate. After rough turning, straightening, rough grinding and other processes must be arranged. When the workpiece is changed, the master mold needs to be replaced, the adjustment time is long, the switching efficiency is low, and the cost is high. The new process camshaft main journal adopts CNC lathe, and the Engine Camshaft For Mercedes Benz adopts CNC external milling for high-speed milling (alloy steel forging blank) or CBN powerful grinding (cast iron casting blank). The rough machining of camshaft has experienced the development history of single-tool turning, multi-tool turning, CNC turning and CNC high-speed external milling.
Before the 1970s, multiple turning tools were used to align the outer circle and fillet of the journal at one time And the side and steps are processed, but different parts of the same part require multiple processes to complete the rough machining of the journal and connecting rod journal. Multi-tool turning has large margins, the side machining of the balance weight is intermittent cutting, and it is prone to vibration and tooling problems. The tool life is low, the defect rate is high, and the cutting efficiency is low. In the 1970s and 1980s, CNC turning, CNC external milling and CNC internal milling techniques appeared in crankshaft rough machining. At the end of the 1980s and the beginning of the 1990s, the car-drawing and car-car-drawing processes were developed. This process has the advantages of high precision and high efficiency. In the mid-1990s, CNC high-speed external milling was developed. It has higher production efficiency than CNC turning, CNC internal milling and turning-turning on the crankshaft that needs to be processed on the side of the balance weight.
Due to the machining accuracy and machining efficiency, turning is generally only used for spindle neck machining. Crankshaft internal milling and high-speed external milling cannot process axial undercut grooves. When the crankshaft has axial undercut grooves, it should be processed by the turning-turning method. When the side of the crankshaft balance weight needs to be processed, the milling process is much better than the turning process. It has the advantages of high cutting speed, short process time, small cutting force, low temperature rise, high tool life, less tool change, high precision and good machine tool flexibility.