As the core transmission component of an automobile differential assembly, the differential planetary gear features complex involute tooth surfaces, modification coefficients and deep-hole spline structures, which impose extremely high requirements on dimensional accuracy. Lacking the original CAD drawings, the client entrusted Holon 3D technical team with reverse modeling. Using the Holon 3D industrial handheld blue-light 3D scanner combined with professional reverse engineering software, feature fitting and spatial geometry reconstruction were performed on high-density point cloud data. The true physical parameters of the planetary gear were perfectly restored, and a 3D model ready for direct machining was successfully exported.

1. Limitations of traditional measurement methods: The tooth surface of a gear is a complex 3D spatial curved surface with a deep central inner hole. Traditional vernier calipers or coordinate measuring machines (CMM) cannot reach the deep part of the tooth root and blind zones inside the hole. They not only deliver extremely low measurement efficiency, but their contact probes are also very likely to scratch the tooth surface.

2. Inability to model due to missing data: Conventional low-precision scanning equipment struggles to capture dense tooth surfaces with small inclination angles, which tends to cause data fracture and loss. It cannot accurately extract the precise module, pressure angle and modification coefficient of the gear, so the reversely reconstructed model fails to meet practical assembly requirements.

Adopt Holon 3D high-precision blue-light 3D scanner. Leveraging its high-resolution blue fringe projection technology combined with multi-angle rotary table scanning, complete point cloud data of gear outer teeth, end faces and central deep holes can be quickly captured. The scanning accuracy reaches up to 0.02 mm. With non-contact operation throughout the process, extremely pure high-density point cloud is acquired without blind spots. Import the point cloud into Geomagic Design X software and perform reverse solid modeling based on the point cloud to reconstruct all features including tooth profile, tooth direction, inner hole fitting positions and chamfers. The exported STP solid model can be directly applied to CNC machining, mold design and simulation analysis.

扫描数据stl图

逆向建模stp图