VacuGuardTM: Stabilizing Suction, Sealing Dust, and Protecting Performance

Introduction

In street sweepers, managing the pressure inside the pickup head is essential for two core outcomes: consistent suction and effective dust containment. A stable internal pressure ensures debris is lifted predictably across varying road conditions. Just as important, it allows the system to direct airflow in the right way. Without this, even a well-built machine can struggle to hold fine particles.

However, most regenerative sweepers rely solely on the main impeller to create suction and assume that’s enough to manage everything. There’s typically no dedicated mechanism to fine-tune pressure, offload excess air, or enforce inward airflow.The solutions they apply result in inconsistent pickup, premature strain on the system, and visible dust trailing even when the sweeper appears to be working.

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Conventional design practices for suction and dust sealing

Most regenerative sweepers depend entirely on the impeller to create suction. There’s no separate system to regulate or fine-tune internal pressure. These machines assume that impeller speed alone will balance airflow, regardless of debris load, terrain changes, or hose bends. In an attempt to control dust, they often add physical barriers like skirts or gaskets or use high-pressure jets to patch weak zones. But these additions don’t regulate the actual air pressure, they just try to compensate for it after the fact.

Challenges:

Without internal pressure management, the airflow is unstable. Pressure can spike or collapse unpredictably, leading to uneven pickup. As debris load fluctuates, the impeller must work harder to maintain suction, which increases fuel use and wear. Since there’s no offloading mechanism, the system runs under strain, and still often leaks dust at pressure weak points. It becomes reactive, not adaptive, vulnerable to choke, overload, or dust blowback.

To keep dust from escaping, conventional machines rely on passive sealing, rubber skirts, sealed panels, and tight-fitting body joints. These are supported by the suction created by the impeller, which is expected to pull air inward through any micro-gaps. Some machines also use targeted high-pressure air jets to control dust leaks in specific areas.

Challenges:

Over time, rubber skirts wear down and panels loosen, creating unregulated gaps. Because these systems don’t actively maintain negative pressure, they can’t ensure air always flows inward. When leaks happen, fine dust escapes, especially in dry, urban, or high-traffic areas, leaving a visible dust trail. High-pressure jets add complexity, require constant calibration, and can stir up more dust if misaligned. Passive sealing alone can’t prevent fugitive emissions in real-world conditions.

The stratus way to guard your vacuum system

Stratus sweepers solve this with VacuGuardTM Negative Pressure Control. Instead of relying solely on the impeller, VacuGuard strategically bleeds off about 15% of the impeller’s discharge through auxiliary filters and vents it safely to atmosphere.. This controlled release creates a gentle, stable negative pressure inside the pickup head. That pressure stabilizes suction across different conditions and avoids overloading the impeller. Especially important when working in tandem with high-velocity systems like the Air BlasterTM pickup head.

Benefits:

A. Pressure Stability for Consistent Pickup

By holding steady negative pressure, the system avoids suction spikes and collapses. Pickup remains predictable and consistent, even when debris varies or terrain shifts

B. Load Management Without Strain

Because VacuGuard offloads excess pressure automatically, the impeller doesn’t need to work harder than necessary. This reduces fuel use, mechanical wear, and the risk of pressure-related failures. Thus delivering a more resilient, energy-efficient system.

Beyond suction control, VacuGuard also serves a critical role in preventing environmental dust leaks. Stratus sweepers use negative pressure control to maintain a consistently lower pressure inside the sweeper head than outside it. This ensures that if any micro-gaps or seal wear appear, clean ambient air is gently pulled inward, rather than letting fine dust leak outward. Instead of relying on worn skirts or reactive high-pressure jets, the system achieves containment through pressure balance, passively and without energy penalty. This approach directly prevents fugitive dust emissions even as the machine ages or operates in dry, dusty environments.

Benefits:

A. Clean containment without complexity

Air always flows inward at weak points, preventing fine dust from escaping. This removes the need for high-maintenance jets or pressure-dependent skirts.

B. Reliable dust control in real conditions

Because containment relies on stable negative pressure and not seals or components that degrade, Stratus keeps dust locked in even when skirts wear out or panels loosen. That means cleaner operation, fewer emissions, and no trailing dust clouds, even in the toughest sweep zones.

Most sweepers treat airflow as a byproduct of suction, not a design priority. But without stable pressure and intelligent containment, even high-powered machines fall short by straining their components and leaking dust despite good intentions. Stratus approaches it differently. With VacuGuard, pressure becomes a controlled resource, not just an output. It shapes how air moves, how dust is held, and how performance holds steady shift after shift. That’s not just better sweeping; it’s better system engineering.