Work-Hardening Tool Bit for Low-Force High-Speed Machining
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Machining operations, such as drilling, face challenges in balancing speed with thrust force and torque, which can lead to reduced tool life and compromised feature geometry and integrity.
Innovation Solution
The use of a machining device that incorporates a linear motor and rotary motor to provide linear feed movement and superimposed oscillation, along with a tool bit featuring a work-hardening section, optimizes machining parameters like frequency and rotational velocity to minimize thrust force and torque.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If machining operations are performed quickly, then productivity is improved, but thrust force and torque increase causing reduced tool life and compromised feature geometry
Solution Approach 1:
The patent applies ultrasonic vibration to the tool bit at frequencies between 20-100 kHz during machining operations. This vibration reduces the thrust force and torque between the tool and workpiece by creating a dynamic cutting action that minimizes continuous contact pressure, thereby enabling faster machining speeds without compromising tool life
Solution Approach 2:
The patent changes the physical state and properties of the tool bit by incorporating a work-hardening section with altered material composition and microstructure. This section exhibits different mechanical properties (higher hardness, reduced ductility) that resist wear and deformation under high-speed machining conditions, allowing sustained productivity without tool failure
2Productivity
If machining operations are performed quickly, then productivity is improved, but feature geometry and integrity are compromised
Solution Approach 1:
The ultrasonic vibration applied to the tool bit creates a reciprocating cutting action that reduces tool deflection and minimizes vibration-induced errors in the machined feature geometry. This allows maintenance of precise dimensional accuracy even at increased machining speeds
Solution Approach 2:
The work-hardening section maintains dimensional stability and resists thermal expansion and deformation during high-speed machining, ensuring that the machined features maintain their intended geometry and integrity throughout the machining process
3Loss of time
If machining operations are performed quickly, then processing time is reduced, but subsequent finishing operations are required increasing overall processing time
Solution Approach 1:
The tool bit is designed to perform multiple functions: the vibrating cutting edges perform the primary machining operation, while the work-hardening section simultaneously performs finishing and strengthening operations on the machined surface. This multi-functionality eliminates the need for separate finishing operations, reducing overall processing time while maintaining productivity
Data Source
AI summary
A tool bit includes a shaft that defines a bit axis and has a first end and a second end. There is at least one work-hardening section adjacent the second end. The at least one work-hardening section has a profile that either is cylindrical or is a portion of a sphere. The at least one work-hardening section defines a smooth working surface.