Intermittent Coolant Drill Design for Chip Evacuation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Chip jamming occurs during drilling of difficult-to-machine materials like Titanium alloys, causing blockages in chip flutes and impairing hole quality and drill tool longevity.
Innovation Solution
A drill design featuring intermittent coolant distribution through a distributor device with a rotatable impeller and flow re-directing element, creating bursts of pressure in chip flutes to dislodge jammed chips and prevent re-jamming, utilizing a coolant chamber with multiple channels and adjustable impeller blades for optimized flow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If continuous coolant flow is used in chip flutes, then cooling effect is maintained, but chip jamming occurs blocking the chip flute
Solution Approach 1:
The patent applies periodic action by using an impeller to create intermittent coolant bursts in the chip flutes. The impeller rotates to periodically direct coolant flow into the chip flutes, creating alternating periods of high-pressure coolant injection and reduced flow. This periodic action prevents continuous chip jamming while maintaining adequate cooling through the cumulative effect of repeated coolant delivery cycles.
Solution Approach 2:
The patent changes the flow parameter of coolant from continuous to intermittent through the impeller mechanism. By varying the flow rate and pressure dynamically during rotation, the system creates high-pressure bursts that dislodge jammed chips while still providing sufficient total coolant volume for thermal management. The parameter change transforms the coolant delivery mode to resolve the contradiction between continuous cooling and chip evacuation.
2Reliability
If intermittent coolant distribution is used, then chip jamming is reduced, but cooling continuity may be compromised
Solution Approach 1:
The periodic rotation of the impeller creates regular intervals of coolant delivery that accumulate cooling effect over time. Each rotation cycle delivers concentrated coolant bursts to different chip flutes, ensuring all cutting edges receive cooling periodically. The frequency of rotation is designed to maintain average cooling levels while preventing chip jamming through the intermittent nature of delivery.
Solution Approach 2:
The impeller stores coolant in its chambers during the non-delivery phase of rotation, preparing coolant for the next burst. This preliminary accumulation ensures that when the impeller directs coolant into the chip flutes, sufficient coolant volume is available to both cool the cutting zone and flush out chips effectively, bridging the gap between intermittent delivery and continuous cooling requirements.
3Reliability
If high pressure coolant bursts are used, then jammed chips are dislodged, but energy consumption increases
Solution Approach 1:
The impeller converts rotational mechanical energy into periodic high-pressure coolant bursts only during the delivery phase of rotation. During the non-delivery phase, the impeller passively accumulates coolant without energy input. This periodic conversion of energy to high-pressure flow reduces overall energy consumption compared to maintaining continuous high-pressure coolant delivery, while still achieving effective chip dislodgement during active bursts.
Solution Approach 2:
The system uses hydraulic principles where the impeller acts as a hydraulic pump, converting rotational motion into pressure pulses. The impeller chambers function as hydraulic accumulators that store pressurized coolant and release it periodically. This hydraulic mechanism achieves high-pressure coolant delivery with lower overall energy input compared to continuous high-pressure pumping, as energy is applied only during the pressurization phase rather than continuously.
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
Effectively reduces the risk of chip jamming and improves coolant flow efficiency, ensuring unhindered chip evacuation and prolonged drill tool life by using intermittent coolant bursts to dislodge stuck chips and maintain continuous cooling.
Implementation Method 1
The intermittent flow of coolant in the chip flutes creates quick bursts of increased pressure in the chip flutes which more efficiently removes jammed chips
Implementation Method 2
it is important to use a coolant to cool the drill and the work piece
Data Source
Figure 1a~1b
Figure 2a~2b
Figure 3a~3b
AI summary
A drill 10 for metal cutting machining having a central rotation axis C defining a longitudinal direction of the drill 10 and around which the drill is rotatable, comprising: an axially front end 12, an axially rear end 14, an envelope surface 16 extending between the front end 12 and the rear end 14, a shaft 22 extending axially rearward from the front end 12, a shank 20 extending axially forward from the rear end 14, at least one cutting insert 18 releasably mounted at the front end 12, a first 25 and a second chip flute 26 in the envelope surface 16 of the shaft 22, a coolant chamber inside the shank 20, a first 27 and second 28 coolant channel extending from the front end of the coolant chamber and terminating at the front end 12 of the drill, the first coolant channel 27 is associated with the first chip flute 25 and the second coolant channel 28 is associated with the second chip flute 26, wherein the coolant chamber comprises a distributor device 40 adapted to intermittently distribute coolant to the first 27 and second coolant channel 28.