Curved Cutting Insert Geometry for Involute Gear Tooth Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The high cost and complexity of forming cutting edges with an involute curve shape in cutting inserts for gear cutting, requiring sophisticated techniques and long manufacturing times, necessitate a more efficient and cost-effective solution for forming tooth spaces.
Innovation Solution
A cutting insert with a cutting edge that follows a first curved shape with a constant curvature radius when viewed from the end surface and a second curved shape with a different curvature radius when viewed from the side surface, allowing for a shape highly similar to an involute curve, and an indexable rotary cutting tool with detachable inserts that utilize a sloped seating surface for secure mounting.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the cutting edge is formed into a precise involute curve shape, then the gear tooth space accuracy is improved, but the manufacturing cost and time increase significantly
Solution Approach 1:
The cutting edge is formed with a specific curvature radius R1 when viewed from the end surface, creating a convex or concave curved shape. This spherical/curved geometry approximation achieves sufficient gear tooth accuracy without requiring complex involute curve formation processes, thereby reducing manufacturing difficulty while maintaining functional precision.
2Ease of manufacture
If the cutting edge follows a simple curved shape, then the manufacturing cost is reduced, but the similarity to involute curve decreases
Solution Approach 1:
The cutting edge geometry is defined by combining curvature in two different dimensions: a first curvature radius R1 when viewed from the end surface (one dimension) and a second curvature radius R2 when viewed from the side surface (another dimension). This multi-dimensional curvature combination creates a three-dimensional shape that approximates the involute curve more effectively than simple two-dimensional curves, achieving both manufacturing simplicity and geometric accuracy.
Solution Approach 2:
By adjusting the parameters of the two curvature radii (R1 and R2) independently, the cutting edge geometry can be optimized to achieve high similarity to the involute curve. The specific values and relationships between R1 and R2 are tuned to minimize the difference from the ideal involute profile, thereby improving manufacturing precision while maintaining the simplicity of the curved shape formation process.
3Manufacturing precision
If the cutting edge has different curvature radii in different viewing directions, then the three-dimensional shape accuracy is improved, but the manufacturing process complexity increases
Solution Approach 1:
The complex three-dimensional cutting edge geometry is segmented into two independent curvature components: one curvature (R1) controlled when viewed from the end surface, and another curvature (R2) controlled when viewed from the side surface. This segmentation allows each curvature to be formed and controlled separately through simpler manufacturing operations, reducing the overall process complexity while achieving accurate three-dimensional shape through the combination of the two curved surfaces.
Data Source
Figure 1A
Figure 1B
Figure 1C
AI summary
The present invention provides a cutting insert (1) including a cutting edge having an involute-curve approximate shape. A cutting edge (18) is formed so as to wholly take on a first curved shape with a first curvature radius when the cutting insert is viewed from the end surface, and is formed so that a large part of the cutting edge (18) takes on a second curved shape with a second curvature radius when the cutting insert is viewed from the side surface.