Profile Groove Forming in Key Blanks Using Longitudinal Broaching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for forming profile grooves in key blanks, such as using rotating cutter discs or linearly guided punching tools, are limited in shaping complexity and often result in material deformation, especially when creating undercut grooves, which can lead to key blank deformation and rendering the key useless.
Innovation Solution
A method and apparatus that utilize a longitudinally guided punching or broaching tool with cutting teeth, secured to a slide member and guided by a fixture with holding surfaces, to form profile grooves without deforming the key blank material, allowing for precise shaping and retention of the key blank during the process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If linearly guided punching tools or broaching tools are used to form profile grooves in key blanks, then complex geometrical shapes including undercut grooves can be created, but the material of the key blank adjacent to the groove being formed is deformed due to strong forces
Solution Approach 1:
The key blank is firmly held in a fixture before the punching or broaching operation begins. The holding surfaces of the fixture are positioned to abut against longitudinal side surface portions adjacent to where the profile groove will be formed, preventing material deformation during the cutting process.
Solution Approach 2:
The fixture divides the key blank into supported regions (adjacent to holding surfaces) and the groove formation region. This segmentation allows the supported portions to remain fixed while the cutting tool forms the groove, preventing floating and deformation of the material.
2Productivity
If conventional rotating cutter discs are used to form profile grooves, then the process is simple and fast, but the shape of the profile groove is limited and cannot create complex geometrical shapes or undercut grooves
Solution Approach 1:
The conventional rotating cutter disc system is replaced with a linearly guided punching or broaching tool system. This substitution enables the formation of complex geometrical shapes and undercut grooves while maintaining high-speed serial production capability through the linear guidance mechanism.
3Device complexity
If punching tools are used without proper holding fixtures, then the process is simpler, but the key blank material floats and deforms during the forming process making the finished key useless
Solution Approach 1:
The key blank is firmly held in a fixture before the punching or broaching operation begins. The holding surfaces of the fixture are positioned to abut against longitudinal side surface portions adjacent to where the profile groove will be formed, preventing material deformation during the cutting process.
Solution Approach 2:
The fixture acts as an intermediary between the punching tool and the key blank. It provides the necessary support and constraint to the key blank, allowing the punching tool to form the groove without causing material floating or deformation.
Data Source
AI summary
A method and an apparatus for forming a profile groove in an elongated key blank having a key blade with opposite side surfaces. The profile groove is formed in a surface of the key blank by a punching or a broaching tool with at least one tooth. The punching or broaching tool is forced and guided longitudinally in parallel to the key blank so as to cut out the material of the key blank into the desired profile shape, corresponding to the cross-sectional shape of the at least one tooth. At the same time, the opposite side surfaces portions of the key blank are clamped or held firmly between opposite holding surfaces of a fixture, causing a firm abutment and retaining action on the longitudinal side surface portions of the key blank located adjacent to and all along the profile groove being formed.