Actuator Mechanism
High speed air switches provide the physical force needed to remove contaminants from a moving stream of fiber. Each pneumatic ejection valve is controlled by a digital signal from an optical sensor or a computer processor. When a defect is identified, the valve opens for a few milliseconds to release a concentrated blast of air.
This mechanical action redirects the contaminated material into a waste duct while allowing the clean fiber to proceed.
Response Time
Precision in the timing of the air burst is essential for efficient sorting. The pneumatic ejection valve must open and close within a very narrow window to avoid wasting good cotton. Delays in the valve movement would result in the contaminant passing through or the wrong tuft being ejected.
Performance is often measured by the number of cycles the valve can complete per second.
Material Loss
Selectivity of the system depends on the width and duration of the air pulse. If the pneumatic ejection valve stays open too long, a significant amount of clean lint is thrown into the waste pile. Modern designs use arrays of many small valves to target specific areas across the width of the duct.
This localized action minimizes the volume of material removed during each event.
Operational Life
Constant cycling in a dusty mill environment requires durable components and frequent maintenance. The seals inside a pneumatic ejection valve must withstand millions of operations without leaking or sticking. Reliable performance ensures that the contamination levels in the final yarn remain within the specified limits.
