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US 6,167,107 AGranted
Air pump for particle sensing using regenerative fan, and associated methods
AssigneeParticle Measuring Systems, Inc.
InventorThomas Bates
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AssigneeParticle Measuring Systems, Inc.
InventorThomas Bates
Estimating the term…
The invention includes a particle sensor with a particle counter. A regenerative blower pulls ambient air into a flow within the particle counter, and a laser illuminates the flow to generate laser radiation indicative of particles within the flow. A detector detects the laser radiation; and particle sensing electronics counts particles within the flow at a preselected volumetric flow rate, e.g., 1 CFM. Preferably, the particle counter includes a plurality of pressure sensors; and a blower speed voltage controller adjusts the speed of the blower according to signals from the pressure sensors to achieve the preselected volumetric flow rate. The regenerative blower permits use of a high efficiency exhaust filter to filter air exhausted from the blower. An airflow path between the particle counter and the regenerative blower preferably has at least one bend between the particle counter and the blower to increase compactness of the system. An aerosol manifold can be connected for fluid communication with an inlet of the particle counter such that the regenerative blower draws air from the manifold at the preselected volumetric flow rate. The manifold samples ambient atmospheric air at a second CFM rate, e.g., 3 CFM, that is greater than the preselected volumetric flow rate. A turbomolecular pump can replace the regenerative blower for high pressure differential particle sensing environments.
A method of controlling volumetric flow rate for a particle counter in ambient atmosphere, comprising the steps of:
A particle sensor, comprising:
A particle sensing system, comprising a particle counter, a regenerative blower for pulling ambient air through an airflow tube into a flow within the particle counter, a plurality of pressure sensors, a blower speed voltage controller for adjusting the speed of the blower according to signals from the pressure sensors to achieve a first volumetric flow rate within the particle counter, an aerosol manifold connected in fluid communication with the particle counter to deliver ambient air to the particle counter at the first volumetric flow rate, a high-flow rate manifold pump connected to capture exhaust from the regenerative blower and the manifold such that the manifold draws ambient atmospheric air within the manifold at a second volumetric flow rate that is greater than the first volumetric flow rate.
A particle sensor, comprising:
Dependencies are inferred from the claim text.