Burr generation is one of the common phenomena in metal machining process. Burrs (metal burrs) mainly refer to the various irregular metal fragments that remain on the surface of the part (such as borders, corners, and edges) during different forms of machining. The formation of metal machining burrs is affected by factors such as cutting angle, control of cutting speed, and control of metal cutting force.
In recent years, with the increasing demand for high-precision parts in automated machining and other machinery manufacturing technology, it has been found that the presence of burrs directly affect the production, use, assembly and aesthetics of the parts.
At present, the main deburring methods are electrochemical deburring, ultrasonic deburring, high-pressure water jet deburring, laser deburring, grinding deburring and robot deburring. However, different methods are applicable to different sizes of workpieces, machining accuracy, materials, burr size. Considering the characteristics of gearbox metal components and their burrs, technology research can be conducted on the robot deburring.
Current Status of Deburring Metal Components in Gearboxes
Gearboxes metal parts refer to the custom-made parts other than gears, bearings and cases, mainly including bearing housings, sealing covers, sealing rings and other metal parts. Due to the complex structure like angled holes, intersecting holes, and intersecting hole slots, burrs inevitably form at the intersections of surfaces during machining. These burrs range in size from 1 cm to 0.1 mm.
In addition, the residual burr also has the challenges like high toughness, hardness, incomplete separation from the workpiece substrate, and limited tool access, making the removal of the burr difficult.
Currently, the gearbox metal parts are mainly removed by manual, using tools such as scraper, reamer, grinding head, sandpaper. However, manual deburring has several issues due to the varying skill levels and experience of workers:
- Low Efficiency: For instance, each worker can only complete 2-3 large bearing seats per shift for a specific model.
- Inconsistent Quality: There is a tendency for burrs to be missed or inadequately removed.
- Bottleneck Process: High labor demand and high manual costs.
Robotic Deburring Process Design
Considering the processing characteristics of gearbox metal parts of multiple types and small batches and the demand for cleanliness, although the robot deburring equipment has the advantages of speed, flexibility, positioning accuracy and so on, the deburring process still needs to be further designed and optimised in order to meet the requirements of the production cycle of a single part processing time of less than 8 min and the demand for cleanliness.
Gearbox components deburring is difficult to remove the large burrs adhering to the substrate, the part of the burr and the workpiece substrate is not completely separated, especially the coherent holes, holes and grooves through the burr; this part of the burr is generally closely connected with the workpiece substrate and in the interior of the workpiece, deburring tools deep inside the holes, the burr is flipped to the other side of the non-processing area, removal difficulties.
Therefore, deburring should first solve the problem of large burr adhesion, and then solve the small burr, small flange, etc., that is, you need to choose the appropriate tool to solve the root of the large burr and the base of the workpiece is not separated from the problem, and then choose the appropriate tool to grind the interface at the interface of the small burr, so the choice of tool is the focus.
Deburring cutter has many, can be roughly divided into cutting and grinding class 2 kinds, cutting class cutter has reamer, chamfering knife, ball cutter, plane milling cutter and other machining tools, grinding class cutter has all kinds of wire brush, brush, grinding wheel, grinding wheel and so on. According to the processing characteristics of various tools and experimental verification, for the gear box metal parts of the coherent holes, holes and grooves through the adhesion of the burr, if the hole burr and the substrate is completely separated, you can use a large front angle of the cutting tool, such as the plane milling cutter; deburring, the first plane milling cutter sharp tip to remove the substrate and the burr connected to the use of wire brushes to remove the fine burrs and flanges.
For the hole burrs on the surface of the workpiece, you can use a chamfering cutter to remove large burrs, and then use a brush to remove small burrs; for the burrs in the groove, you can use a ball knife or a small grinding head to remove. For the circumferential direction of the outer surface of the workpiece burrs, you can directly use machining tools on the sharp corners of the chamfering and then grinding with the end brush.
In summary, the adhesion of large burrs on the gear components should be removed using a plane milling cutter, chamfering cutter and other cutting tools with a large front angle, and then use wire brushes, brushes and other grinding tools to remove small burrs.
Conclusion
Due to the complexity of the deburring processing environment, the robot controller needs to respond according to the different environments, robot deburring technology is also progressing and widely used in precision parts manufacturing.
Robot deburring equipment integrated 6-axis multi-joint robot, flexible pneumatic chuck and quick-change mechanism and other advanced technologies, is suitable for the complex structure of various types of parts deburring operations of professional, automated integrated equipment.
The deburring robot realizes the deburring of all kinds of metal parts of the gearbox, and the deburring residual rate of the processed parts is low, which greatly improves the production efficiency and the production environment, and it has the advantages of convenient operation, rapidity, high efficiency and so on.
