Expandable Drill Bushing Anchoring Thin-Walled Pilot Holes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing drill bushing technologies face challenges in securely anchoring to thin-walled workpieces during drilling operations, as they often lack sufficient surface area for effective gripping, leading to instability and potential misalignment of pilot holes during hole transfer processes.
Innovation Solution
A drill bushing with an expandable retaining member and adjustment mechanism, featuring a split design and threaded rod system, which increases the outer diameter of the retaining member to securely grip the pilot hole wall, preventing the bushing from working loose during drilling, even on thin materials.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a traditional drill bushing is used on thin-walled workpieces, then the drilling operation can be performed, but the bushing lacks sufficient gripping surface area leading to instability and potential misalignment
Solution Approach 1:
The drill bushing incorporates an expandable retaining member that can dynamically adjust its outer diameter. The retaining member is initially in a collapsed state for insertion into the pilot hole, then expands to a larger diameter to grip the pilot hole wall securely. This dynamic expansion allows the bushing to adapt to thin-walled workpieces by increasing its gripping surface area only when needed, providing stable anchoring without requiring excessive initial surface area.
Solution Approach 2:
The invention changes the physical parameter of the retaining member's outer diameter from a fixed value to a variable value. By adjusting the outer diameter of the retaining member between a first diameter (collapsed state) and a second diameter (expanded state), the system can optimize gripping surface area based on the specific application requirements. This parameter change enables the same bushing design to work effectively on workpieces of varying thicknesses.
2Reliability
If the drill bushing is made expandable with an adjustment mechanism, then secure gripping on thin materials is achieved, but the device complexity increases
Solution Approach 1:
The drill bushing is segmented into distinct functional components: a base member, a separate retaining member with a split design, and an adjustment member. The retaining member is further segmented along its circumference by the split, allowing it to flex and expand. This segmentation enables each component to perform its specific function independently while simplifying the overall assembly and adjustment mechanism.
Solution Approach 2:
The adjustment mechanism is designed to be self-operating through a simple threaded rod system. By rotating the threaded rod, the retaining member automatically expands or collapses without requiring complex actuators, motors, or external power sources. The threaded rod converts rotational motion directly into linear expansion/contraction of the retaining member, providing a self-contained adjustment system that minimizes overall device complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution enables accurate and stable transfer of pilot holes from one workpiece to another, ensuring the drill bushing remains anchored and aligned, even on thin-walled materials, by increasing friction through adjustable expansion of the retaining member.
Implementation Method 1
increasing friction through adjustable expansion of the retaining member
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A drill bushing (124) for a drill unit (122). The drill bushing includes a base member (202) having an upper surface (204), a lower surface (206) configured to rest on a workpiece (102) having a pilot hole (104), and a retaining member (316) that projects from the lower surface of the base member. The retaining member has a cylindrical outer diameter suitable to fit within the pilot hole. The drill bushing further includes a drill hole (210) that passes from the upper surface of the base member through the retaining member to provide a passage for a drill bit. The drill bushing further includes an expandable slit (214) that passes through the base member and the retaining member to the drill hole, and an adjustment member (218) configured to expand the expandable slit to increase the cylindrical outer diameter of the retaining member within the pilot hole.