Cutting Tool Holder Groove Design for Insert Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cutting tool holders experience tilting and chattering issues due to the rigidity decline and oblique slit formation, which complicates processing multiple holders in a row and affects cutting performance.
Innovation Solution
A holder design featuring a bar-shaped shank with a head portion including an insert attaching space, upper and lower jaws, and a column-shaped groove that reduces the holder's thickness, preventing the insert from tilting and enhancing rigidity by extending halfway through the slit, thus securely fastening the insert and suppressing chattering.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the slit terminal length is made oblique to prevent insert tilting, then insert stability is improved, but holder rigidity deteriorates causing chattering
Solution Approach 1:
The groove is localized at the deepest end of the slit rather than making the entire slit oblique. This local modification allows the upper jaw to deform for insert retention while maintaining overall holder rigidity, resolving the contradiction between insert stability and holder strength
Solution Approach 2:
The holder structure is segmented into regions with different functions: the groove creates a localized flexible zone at the slit deepest end for insert retention, while the rest of the holder maintains full rigidity for stable cutting, thus resolving the contradiction through functional segmentation
2Reliability
If the groove extends throughout the holder to the opposite lateral face, then insert retention is improved, but holder rigidity deteriorates
Solution Approach 1:
The groove extends partially from the lateral face toward the opposite lateral face but stops before reaching it. This partial extension provides sufficient upper jaw deformation for insert retention while avoiding excessive rigidity loss that would cause chattering during cutting
3Manufacturing precision
If the slit is formed obliquely to prevent insert tilting, then insert positioning is improved, but manufacturing complexity increases
Solution Approach 1:
Instead of making the entire slit oblique (asymmetric), the invention uses a symmetric holder body with a localized asymmetric groove feature. This maintains manufacturing simplicity for the holder while achieving precise insert positioning through the groove's asymmetric shape relative to the slit
Data Source
Figure 1(a)~1(b)
Figure 2(a)~2(c)
Figure 3(a)~3(b)
AI summary
[Object] To provide a throwaway cutting tool that allows an insert to be easily attached and removed, and accurately fixed with pressure. [Solution] A holder for grooving work 2 includes a shank portion 3, and a head portion located on an end portion of the shank portion 3 and integrally formed therewith. The head portion 4 includes an insert attaching space 5, an upper jaw 7 and a lower jaw 8 respectively located above and below the insert attaching space 5, a slit 9 extending backward from the insert attaching space 5, an upper jaw connecting portion 11 and a lower jaw connecting portion 12 divided by the slit 9, an upper clamp surface 18 on the upper jaw 7 opposed to the insert attaching space 5, a lower clamp surface 19 on the lower jaw 8 opposed to the insert attaching space 5. A column-shaped groove 20 is connected to the deepest end of the slit 9. The column-shaped groove 20 is formed so as to reduce the thickness of the upper jaw connecting portion 11, and extends from the lateral face on the side of the insert attaching space 5 halfway along the deepest end of the slit 9 toward the opposite lateral face. Upon attaching the insert 30 to the holder 2 the cutting tool 1 is obtained.