Helical Broaching Tool With Hard-Metal Sizing for Longer Service Life
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing internal helical broaching tools face challenges in extending their service life while maintaining defined machining performance.
Innovation Solution
The internal helical broaching tool is designed with a pre-broaching tool portion and a subsequent precise sizing tool portion, where the precise sizing tool portion is made of hard metal with a density greater than 10 g/cm3, and broaching teeth have a positive rake angle.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of moving object
If the precise sizing tool portion is made of high-speed steel, then the tool has good ductile properties and can withstand tool loads, but the service life is limited
Solution Approach 1:
The patent changes the material parameter from high-speed steel to hard metal with density greater than 10 g/cm³, fundamentally altering the physical properties of the precise sizing tool portion. This parameter change enables the tool to achieve extended service life through superior wear resistance while maintaining sufficient strength to withstand helical broaching loads including impact and torsional stresses
Solution Approach 2:
The patent employs composite material structure by combining pre-broaching tool portion (made of high-speed steel or other materials) with precise sizing tool portion (made of hard metal). This composite approach allows each portion to be optimized for its specific function: the pre-broaching portion handles rough material removal while the hard metal precise sizing portion provides extended service life for the critical finishing operation
2Duration of action of moving object
If hard metal is used for the precise sizing tool portion, then the service life is extended, but the manufacturing precision and accuracy require advanced machining methods
Solution Approach 1:
The patent replaces conventional mechanical machining methods with diamond grinding technology for manufacturing the hard metal precise sizing tool portion. Diamond grinding wheels with controlled alignment and optical monitoring enable accurate machining of hard metal materials that cannot be effectively processed by traditional cutting methods, thereby achieving the required manufacturing precision despite the material change
Solution Approach 2:
The patent implements feedback control in the manufacturing process through optical monitoring of the diamond grinding wheel dressing process. This feedback mechanism detects actual profile values during grinding and allows real-time adjustments to maintain manufacturing tolerances corresponding to state-of-the-art precision levels, ensuring the hard metal tool portion achieves the necessary geometric accuracy
3Productivity
If the broaching teeth are arranged obliquely along helical broaching paths, then the helical broaching function is achieved, but the tool structure becomes more complex
Solution Approach 1:
The patent divides the broaching tool into functionally distinct segments: pre-broaching tool portion with broaching teeth arranged obliquely along helical paths for creating the helical groove, and precise sizing tool portion with broaching teeth arranged axially for final dimensioning. This segmentation allows each portion to be optimized for its specific function while simplifying the overall design and manufacturing of the composite tool structure
Data Source
AI summary
An internal helical broaching tool has a pre-broaching tool portion ex-tending in one broaching direction and a subsequent precise sizing tool portion. The latter, as a whole, is made of a hard metal with a density of greater than 10 g/cm3. This results in an internal helical broaching tool with increased service life at a defined machining performance.