Research And Design On High Precision Online Punching Device Of Non-load Type Automobile Chassis

The frame is an important carrier of non bearing body vehicle,most important components affecting vehicle performances such as power system,driving system,shock absorber system are installed on the frame;therefore the accuracy of frame is one of the most important factors affecting the performances of vehicle.four wheels alignment parameters,driving bias,tire wear,vehicle jitter problems are all related to the accuracy of frame..The plate thickness of the frame is 2.0-4.0mm,and the CO₂ gas shielded welding is normally adopted.The total length of the welding is about 70 meters,and the welding deformation is very large,however,it is more difficult to avoid,so the accuracy of the frame is difficult to ensure.Using the online punching technology,which means punching holes after welding,can effectively improve the accuracy of the frame.It is of great significance to develop an online punching device which can adapt to the thick plate frame.Online punching device combines die punching,welding fixture,pneumatic technology,hydraulic technology and electronic control technology,adopting the double floating piercing mode,of which novel punch and die can sliding,instead of the traditional mode of punching mould,the device can connect double punching making punch at one time to solve the layout space lacking problem of punching device.The force increasing mechanism is used in many positions of the online punching device,the pneumatic and hydraulic power output is enlarged exponentially,the size of the mechanism is reduced,and the piercing function is realized by the precise control of the PLC.With the online punching device,the precision of the frame is up to±1.0mm,CPk reaches to 1.33,the ability to guarantee the accuracy is up level obviously.