Spray Arrangement for Binding Dust in Machining Tools
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing tools with spray devices for dust control, such as cut-off grinders and angle grinders, are inadequate in reducing exposure to fine dust particles, particularly the respirable fraction, and require excessive liquid for dust binding, limiting their effectiveness and usability.
Innovation Solution
A spray device with a first spray nozzle emitting liquid droplets of 40-150 μm at a flow rate of 8-12 liters per hour and a pressure of 5-8 bar, and a second spray nozzle for cooling and lubrication, arranged to direct spray jets at angles up to ±10° relative to the processing plane, effectively binding respirable dust and reducing liquid requirements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If spray nozzles are arranged on the entry side of the cutting disc with pressure of 2-4 bar, then cooling of the cutting disc is achieved, but fine dust particles (especially respirable fraction) are not effectively suppressed
Solution Approach 1:
The spray device is segmented into two independent spray nozzle systems: first spray nozzles (8-12 l/h, 5-8 bar) positioned at the exit side specifically for dust suppression, and second spray nozzles positioned at the entry side for cooling and lubrication. This segmentation allows each subsystem to be optimized for its specific function without compromising the other, resolving the contradiction between cooling effectiveness and dust suppression capability.
Solution Approach 2:
Different spray characteristics are applied to different locations: the first spray nozzles produce finer droplets (40-150 μm) at higher pressure (5-8 bar) at the exit side where dust generation occurs, while the second spray nozzles operate at lower pressure for cooling at the entry side. This local differentiation of spray quality enables simultaneous optimization of dust binding and cooling functions.
2Object-affected harmful factors
If high flow rate spray nozzles are used for dust suppression, then fine dust particles are bound, but excessive liquid consumption occurs
Solution Approach 1:
The first spray nozzles are designed with specific parameters: flow rate of 8-12 l/h (significantly reduced from conventional high flow rates), pressure of 5-8 bar, and droplet size of 40-150 μm. These parameter changes optimize the balance between dust binding effectiveness and liquid consumption, achieving sufficient dust suppression with minimal liquid usage.
Solution Approach 2:
Instead of using high flow rates to ensure complete dust coverage, the invention uses precisely controlled partial action with 8-12 l/h flow rate at optimized pressure and droplet size, achieving effective dust binding with exactly the right amount of liquid rather than excessive quantities.
3Object-affected harmful factors
If spray pressure is increased to improve dust suppression, then fine dust particles are bound more effectively, but liquid disperses too widely reducing efficiency
Solution Approach 1:
The spray pressure is optimized to 5-8 bar (moderate pressure, not excessively high), combined with droplet size control of 40-150 μm through nozzle design. This parameter combination achieves effective dust binding while maintaining controlled spray pattern and efficient liquid distribution, preventing excessive dispersion.
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
Significantly reduces operator exposure to fine dust, especially the respirable fraction, while minimizing liquid usage and enhancing machining tool performance through efficient dust binding and cooling.
Implementation Method 1
a first spray nozzle (37) which, via a first connecting line (38), is connected to pump (36), emits liquid droplets with a size between 40 and 150 μm as the first spray jet
Implementation Method 2
a second spray nozzle (39) for cooling and lubricating the machining tool (12), the second spray nozzle (39) being connected via a second connecting line (41) to pump (36)
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A tool device (10) for machining a workpiece (23), having a machining tool (12), which can be rotated by a drive device (13) in a rotational direction (14) about a rotational axis (15), a protective hood (25), which surrounds the machining tool (12) at least partially, and a spray arrangement (11) with a first spray nozzle (37) and a pump (36), which is connected to the first spray nozzle (37) via a first connecting line (38), wherein the pump (36) generates a minimum pressure of 5 bar in the first connecting line (38).