Drill Head Margin and Guide Pad Length Balance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional drill heads for deep hole machining in BTA and ejecting systems suffer from reduced circularity and straightness due to an imbalance between the length of guide pads and the margin of cutting blades, leading to compromised precision in hole machining.
Innovation Solution
The drill head design ensures that the length of the margin at the cutting blade's periphery in the axis direction is made substantially equal to the length of the guide pads, with the top and rear ends aligned in the circumference direction, establishing a pressure balance between the margin and guide pads.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the length of guide pads is made larger than the margin of cutting blades, then the guide pads can provide sufficient guidance support, but the circularity and straightness of the machined hole deteriorates
Solution Approach 1:
The patent applies parameter changes by precisely adjusting the length of the guide pads and the margin of the cutting blades to be substantially equal. This parameter optimization resolves the contradiction by eliminating the excessive length of guide pads that caused pressure imbalance, thereby improving hole circularity and straightness while maintaining sufficient guidance support functionality.
2Ease of operation
If the length of guide pads is made larger than the margin of cutting blades, then the guide structure provides extended support, but the pressure balance between margin and guide pads deteriorates
Solution Approach 1:
The patent applies parameter changes by setting the guide pad length equal to the cutting blade margin length. This parameter optimization restores the pressure balance between the margin and guide pads, ensuring stable cutting forces and proper distribution of cutting resistance, thereby resolving the contradiction between guidance support and pressure balance.
3Device complexity
If the margin of cutting blades is made shorter than the guide pads, then the cutting blade structure is compact, but the precision of hole machining deteriorates
Solution Approach 1:
The patent applies parameter changes by increasing the margin length of the cutting blade to be substantially equal to the guide pad length. This parameter adjustment ensures that the margin provides adequate support and guidance during the initial stage of hole formation, thereby improving hole machining precision while maintaining a compact cutting blade structure.
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 design enhances the circularity, straightness, and precision of hole machining by securing a pressure balance, resulting in improved cylindricality and machining accuracy.
Implementation Method 1
high-pressure cutting oil is fed to a tip of a cutting blade through the inside of a shank of a drill, the swarf generated by the cutting blade is broken by the high-pressure cutting oil, and the broken swarf is forcibly ejected through the V-groove
Implementation Method 2
a pressure difference is generated, and an absorbing force is generated. Swarf is absorbed by a vacuum effect of the absorbing force and ejected from the ejecting port
Implementation Method 3
the inner pressure of the inner tube becomes negative, a pressure difference is generated, and an absorbing force is generated. Swarf is absorbed by a vacuum effect of the absorbing force
Implementation Method 4
the length Lm of a margin 6, which is formed at a tip side of a periphery of the cutting blades 12 and 12a in a drill rotating direction, in an axis direction is made substantially the same as the length Lp of the guide pads 3 and 4 in the axis direction... pressure balance between the margin and guide pads
Data Source
AI summary
The invention provides a drill head for deep hole machining capable of raising circularity and straightness of a hole and improving precision of hole machining. In the drill head for deep hole machining constituted by fixing a cutting blade to a tip surface of a head body and fixing guide pads to a periphery of a tip of the head body, the length Lm of a margin, which is formed at a tip side of a periphery of the cutting blade in a drill rotating direction, in an axis direction is made substantially the same as the length Lp of the guide pads in the axis direction, and a top end and rear end of the margin are substantially aligned with a top end and rear end of the guide pads, respectively, in a circumference direction.