Spiral Drill Web Groove Flow Contour to Prevent Clogging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Twist drilling tools used for machining light metal workpieces, such as aluminum cylinder blocks, often experience premature clogging of the web groove due to reduced flute depth, leading to impaired process reliability and reduced tool service life.
Innovation Solution
A pump or flow guide contour is formed in the groove bottom of the web groove to ensure a stable and uninterrupted flow of coolant and/or lubricant, preventing clogging by creating a pressure difference that maintains a continuous flow towards the clamping shank, and the design includes a pressure-increasing and pressure-reducing depression to optimize flow guidance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the web groove has reduced flute depth to provide supporting chamfers for process stability, then lateral deflection is prevented and process stability is improved, but the web groove becomes prone to clogging with workpiece material
Solution Approach 1:
The patent applies hydraulic principles by introducing a pump contour in the groove bottom that utilizes coolant flow to generate pressure differences. The pump contour acts as a hydraulic pump, using the kinetic energy of the coolant stream to create suction at the inlet and pressure at the outlet, thereby actively drawing chips through the web groove and preventing clogging despite the reduced flute depth.
Solution Approach 2:
The patent changes the geometric parameters of the groove cross-section by introducing a pump contour with specific dimensions (depth between 0.1-2.0 mm, width at inlet 0.5-3.0 mm). This parameter change transforms the passive groove into an active chip transport system that uses controlled flow parameters to maintain chip flow stability and prevent clogging.
2Temperature
If coolant flow is provided through the web groove without a pump contour, then cooling is achieved, but the flow becomes unstable and turbulent, impairing chip discharge
Solution Approach 1:
The pump contour converts the coolant flow into a controlled hydraulic system that generates stable laminar flow patterns. The contour design ensures that the coolant flows smoothly through the groove with minimal turbulence, maintaining both cooling effectiveness and stable chip transport by preventing flow separation and eddy currents.
Solution Approach 2:
The patent optimizes flow parameters by designing the pump contour with specific geometric parameters that control velocity distribution and pressure gradient. The contour shape is designed to maintain appropriate Reynolds numbers for laminar flow, ensuring stable coolant delivery for cooling while simultaneously providing stable chip discharge.
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
This solution enhances tool service life and process reliability by preventing web groove clogging and ensuring stable chip discharge, maintaining a laminar flow pattern, and reducing tool stress through efficient coolant and lubricant distribution.
Implementation Method 1
With the help of the pump or flow guide contour, an additional pressure difference is generated in the bar groove in order to ensure a stable and steady flow of the coolant and/or lubricant through the bar groove in the direction of the clamping shank
Implementation Method 2
The pump or flow guide contour can have a pressure-increasing, shovel-like or trough-shaped depression in the bottom of the web groove between the drill tip and a crest
Implementation Method 3
Alternatively and/or additionally, the pump or flow guide contour can have a pressure-reducing, blade-like or trough-shaped depression in the bottom of the web groove
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a spiral drill tool with a clamping shank (1) and a drill body (3) adjoining it, along the axis of rotation (R) of which at least one drill web (5) extends spirally to the drill tip, wherein a web groove (26) is formed on the back of the drill web (5), the web groove (26) being defined by two support chamfers (19, 23) spaced apart from each other in the circumferential direction of the drill with an intermediate back surface forming the groove base (25), which is set back radially inwards by a groove depth (t) relative to the support chamfers (19, 23), and wherein at least one cooling and/or lubricant channel (27, 29, 31) runs in the spiral tool, through which the drill tip can be supplied with cooling and/or lubricant. According to the invention, a pump contour orFlow guide contour (41) is formed, by means of which a stable, uninterrupted flow of cooling and/or lubricant (II) through the web groove (26) in the direction of the clamping shaft (1) is ensured during the drilling process.