Expandable Reamer Tapered Pin Coolant Channel Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional reamers, such as solid carbide and brazed carbide reamers, face difficulties in achieving bore holes with small tolerances due to inadequate coolant and lubricant supply, particularly because the shank of the conical screw interferes with the coolant and lubricant channels, limiting their effectiveness.
Innovation Solution
An expandable reamer design featuring a shank portion with a cutting portion having a tapered inner surface and a tapered pin with a corresponding outer surface, allowing for expansion or contraction without interfering with coolant channels, ensuring an optimal supply of coolant and lubricant to the cutting blades.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a conical screw with shank is used to expand the cutter head, then the cutter head can be adjusted for different diameters, but the shank interferes with the coolant and lubricant channels, reducing coolant supply effectiveness
Solution Approach 1:
The patent removes the interfering shank portion from the conical screw design. By extracting the problematic shank element, the coolant channels can be properly positioned and sized without obstruction, allowing adequate coolant and lubricant flow to reach the cutters while maintaining the expansion adjustment capability through the conical geometry alone.
Solution Approach 2:
The patent separates the expansion function from the coolant supply function. The conical screw body provides expansion capability through its tapered geometry, while the coolant channels are independently positioned in the cutter head structure, eliminating the interference that occurred when these functions were combined in a single shanked component.
2Strength
If the shank of the conical screw is present, then the screw can be securely mounted and operated, but it does not leave enough design space for proper placement of coolant channels
Solution Approach 1:
The patent extracts the shank portion that was causing spatial constraints. By removing this element, sufficient design space is created within the cutter head structure to properly position and dimension the coolant channels, allowing them to be placed optimally for effective coolant delivery to all cutters.
3Ease of manufacture
If conventional reamers are used, then the structure is simple and easy to manufacture, but they cannot achieve bore holes with very small tolerances due to inadequate coolant supply
Solution Approach 1:
The patent divides the reamer into modular components: an adjustable cutter head with integrated coolant channels, and a separate expansion mechanism. This segmentation allows the coolant supply system to be independently optimized for precision machining while maintaining the overall simplicity of the adjustable reamer structure.
Solution Approach 2:
By removing the interfering shank element, the patent enables proper coolant channel design that was previously impossible in conventional simple reamer structures. This extraction allows adequate coolant flow to reach the cutters, enabling achievement of very small tolerances (smaller than IT6) while maintaining adjustability.
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 design provides an uninterrupted coolant and lubricant supply to the cutting blades, enhancing the machining process by preventing interference and allowing for precise adjustment, thus improving the machining accuracy and efficiency in tight tolerance bore holes.
Implementation Method 1
a tapered pin causing an expansion or contraction of the cutting portion when the tapered pin is screwed or unscrewed into the cutting portion
Implementation Method 2
at least one coolant channel extending from a coolant cavity through a wall of the cutting portion for providing a supply of coolant to the blades
Data Source
AI summary
An expandable reamer includes a shank portion, a cutting portion extending from the shank portion, and a tapered pin capable of being at least partially received in the cutting portion. The cutting portion includes a plurality of blades separated by flutes, and a tapered inner surface with threads. The tapered pin includes a tapered outer surface with threads and causes expansion or contraction of the cutting portion when the tapered pin is screwed or unscrewed into the cutting portion. In one embodiment, a coolant channel extends from a coolant cavity through a wall of the cutting portion to provide fluid to the blades during machining of through-holes. In another embodiment, the tapered pin includes a coolant passage in fluid communication with the coolant cavity to provide fluid to the blades during machining of blind holes.