Mesosystems Technology, Inc.

Vanessa M Kenning

Patrick T Call

Charles John Call

Joseph G Birmingham

Andrew Kamholz

Christopher L Moler

Eric Hanczyc

Donald J Hammerstrom

Trent Robert Wetherbee

Alireza Shekarriz

Donald J Hammerstom

A method and apparatus for removing concentrated spots of collected particulates from an impact collection surface, and transferring those particulates into a container suitable for preparing a liquid sample. A jet of fluid can be utilized to remove and transfer the particulates. If a liquid jet is employed, care is taken to minimize the quantity of liquid to avoid unnecessarily diluting the sample. A mechanical scraper can alternatively be employed to remove and transfer the particulates into the container. The scraper can be rinsed with liquid or vibrated to remove the particulates. Alternatively, the portion of the surface containing a specific spot of particulates can be removed and placed into a container.

Removing surface deposits of concentrated collected particles

The present invention relates to optimizing the configuration of rotary impact collectors and devices in which such rotary impact collectors are employed. Rotary impact collectors are formed out of base plate upon which a plurality of vanes are mounted. One aspect of the present invention is a combined impact collector and fan in which the ratio of vane height to impeller diameter is in the range of about 0.01 to about 0.2. Preferably, the vanes are evenly spaced around the impeller so as to present a balanced load to the motor. Other performance enhancing elements include the use of truncated vanes, configurations optimized for injection molding fabrication, controlling the orientation of the vanes to reduce the formation of vortex forces, and enhancements configured to increase the ability to collected particles rinsed off such impellers.

Optimizing rotary impact collectors

Method for removing surface deposits of concentrated collected particles

A portable sampling unit capable of separating particulates, including biological organisms, from gaseous fluids such as air. A combined particle impact collector and fan is used to both move fluid through the sampling unit and to collect particulates. In one embodiment, the combined particle impact collector is a disposable unit that is removed and replaced with a fresh unit after each sampling period. The disposable unit is placed in a rinse station, where a liquid sample is extracted for later analysis. Alternatively, a disposable detection unit is incorporated in the sampling unit to provide real time detection of chemical toxins and/or biological pathogens. Preferably, the detector unit includes micro-fluidic channels so that a minimum amount of sample and test reagents are required. In another embodiment, the combined impact collector is integral to the sampling unit, rather than a separate disposable item.

Biological individual sampler

A separation plate separates a major flow of fluid from a minor flow of fluid. The major flow includes a minor portion of particles greater than a &ldquo;cut size,&rdquo; while the minor flow includes a major portion of particles greater than the cut size. Plates define a laterally extending passage between a front of the separation plate and its rear. The passage telescopes or converges from an initial height at its inlet, to a substantially smaller height at its outlet. A slot extends transversely into the plates from within a minor flow portion of the passage and connect into major flow outlet ports. The flow of fluid into the outlet is thus divided into the major flow, which flows from the major flow outlet ports and the minor flow that exits the outlet of the passage. To accommodate a desired flow of fluid, the width of the passage can be changed, or an array of stacked separation plates can be employed.

Virtual impactor

The present invention employs a virtual impactor to separate a flow of fluid into a major flow and a minor flow, such that the minor flow contains a higher concentration of particulates of a desired size. The minor flow is directed toward an archival surface, causing the particulates to impact against and be deposited on the archival surface. Over time, the archival surface and the virtual impactor are moved relative to one another such that particulates collected at different times are deposited as spaced-apart spots on different portions of the archival surface. The particulates are stored on the archival surface until analysis of the particulates is required. The archival surface can be coated with a material that enhances the deposition and retention of the particulates and can further be coated with materials that sustain the life of biological organism particulates deposited on the archival surface.

Method for surface deposition of concentrated airborne particles

Micromachined virtual impactor

A particle collector includes a combined impact collector and fan, which is usable for both drawing air or other gaseous fluid in which particulates are entrained into a cavity, and then separating the particulates from the gaseous fluid by providing a rotating surface that impacts the particulates. The particulates also impact on other surfaces within the cavity, including its inner surface, and are washed from these surfaces, which are wetted with water or other liquid injected into the cavity. The cavity is defined by a housing having an inlet port through which the air or other gaseous fluid is drawn. The combined impact collector and fan includes a plate on which a plurality of spaced-apart impeller vanes are disposed. The shape of the impeller vanes produces a centrifugal fan effect when they are rotated within the cavity. The water or other liquid is either continuously or intermittently injected into the cavity to wash the particulates from the impeller vanes and other surfaces on which they have impacted. The particulates are carried by the liquid through a threaded drain port, into a receiver that includes an exhaust port for the air or gaseous fluid. A pump recirculates the liquid from the receiver through a conduit that sprays the liquid into the cavity through the inlet port. The particulates collected in the receiver provide a specimen that can be analyzed to detect or identify the particulates that were entrained in the air or other gaseous fluid.

Impact particulate collector using a rotary impeller for collecting particulates and moving a fluid

A separation plate (10) includes a first surface (10a) and an opposing second surface. A plurality of teardrop-shaped virtual impactor projections (12) are provided on the first surface, preferably in a plurality of rows (13a, 13b, 13c). Each projection includes a convex leading profile (18) facing a fluid stream (16), and two concave side surfaces (19) that are positioned to define a tapered downstream portion. The convex leading profile may include a concave portion (20). The concave portion defines a virtual impact void therethrough. The virtual impact void defines a terminal end of a passageway that extends through the separation plate to communicate with the second surface. When particle-laden fluid is caused to flow along the first surface, a major portion of the fluid containing a minor portion of particles flows around the teardrop-shaped virtual impactor projections along the first surface. A minor portion of the fluid containing a major portion of particles is collected near the convex leading profiles of the projections, and enters the concave portions and the virtual impact voids of the projections. The minor portion of the fluid then travels through the passageways to the second surface of the separation plate, where it can be collected, analyzed, or processed further.

Micromachined teardrop-shaped virtual impactor

A plurality of micropillars (2) arranged in a plurality of rows (4, 6, 8) are provided. When a particle-laden fluid stream is caused to flow through the micropillars, at least a portion of the particles impacts and becomes deposited on the micropillars' surfaces while the fluid stream is deflected aside. The deposited particles may subsequently be collected.

Micromachined impactor pillars

A separation plate (10) includes a first surface and an opposing second surface. Plural pairs of a nozzle (14) and a virtual impactor (16) are provided on the first surface. Each nozzle tapers from an inlet end (14a) to an outlet end (14b). Each virtual impactor comprises a pair of generally fin-shaped projections (24). Each fin-shaped projection includes an inner wall (26) and a convex outer wall (28). The inner walls of the fin-shaped projections of a virtual impactor face each other to define a minor flow passage (30) therebetween. The convex outer walls of the fin-shaped projections of a virtual impactor cooperatively present a convex surface including a virtual impact void therethrough. The virtual impact void defines an inlet end of the minor flow passage. A virtual impactor body (33) is provided between adjacent virtual impactors (16). When a particle-laden fluid stream (23) is caused to flow through the nozzles and advance to the virtual impactors, a major portion of the fluid containing a minor portion of particles flows around the virtual impactors, is blocked by the virtual impactor bodies, and redirected from the first surface through a suitable major flow outlet. A minor portion of the fluid containing a major portion of particles enters the virtual impact voids, advances through the minor flow passages, and exits therefrom, where it can be collected, analyzed, or processed further in any other manner.

Growing community of inventors

Kennewick, WA, United States of America

Vanessa M Kenning