Bio-rad Laboratories, Inc.

Block Engineering, LLC

David C Brown

Raul Curbelo

Reginald Tobias

T Hirschfeld

An adjustable masking mechanism for use in connection with the exposure of a sample to a beam of analytical radiation and a beam of viewing radiation that facilitates aligning the movable elements of the mask with the edges of the sample. Whereas the prior art mechanisms utilize materials that are opaque to both the analytical radiation and the viewing radiation, the present invention uses one or more movable elements that are substantially opaque to the analytical radiation and at least partially transmissive to at least a portion of the spectral range of the viewing radiation.

Sample masking using wavelength-selective material

An infrared source that operates at about 1150.degree. C. without the need for water cooling. The source is configured with a small surface area radiating element, energized by a high frequency AC square wave. The frequency of the AC square wave is much greater than the inverse of the filament's thermal time constant so that the temperature is very stable. The radiating element is mounted relative to a concave reflector so that the infrared radiation forms a beam suitable for input to a spectrometer. In a first embodiment, the radiating element is in the form of a wire coil, while in a second embodiment, it is in the form of a cylinder having a central portion of reduced diameter.

Low power infrared source assembly for spectrometer

An interferometer bearing assembly including a fixed glass rail, a movable carriage that carries both the movable interferometer mirror and the drive coil for the linear motor, and a mechanism for biasing the carriage onto the rail. The glass rail has two optically flat faces defining a normally horizontal line of intersection. The carriage is a rigid structure with plastic surface portions that provide a bearing interface for contacting the flat faces of the glass rail. To improve stability and reduce the possibility of any transverse movement, the carriage is downward biased, preferably by providing an overlying glass plate with a downwardly-facing flat surface, and mounting a spring-loaded plastic element to the top of the carriage. The plastic element contacts (and slides along) the flat glass surface and transmits a downward force to the carriage.

Interferometer bearing assembly

An improved high resolution chromatograph device operable at column pressures ranging between one and fifty atmospheres absolute measured at the column exit, means for closely regulating the column carrier gas velocity including intermittent stop flow operation, and sample collection chamber means to facilitate contamination free handling and concentration of collected pure sample during spectral or other analysis of eluted samples. Velocity and stop flow control without loss of chromatographic resolution permits matching operation time of chromatograph to that of spectral or other analysis devices.

Gas chromatograph device

A seal apparatus for making demountable gas tight seals between juxtaposed dissimilar material parts in high temperature, high pressure and chemically reactive environments. The seal is comprised of two or more concentric elastomer washer seals mounted in a first juxtaposed part within a recessed channel of measured depth. The washer seals have a thickness greater than the measured depth of the channel, thereby providing contact with the second juxtaposed part interfaced with the first or channeled part. The inner concentric elastomer washer, being made of chemically relatively inert material, and the outer concentric elastomer washer being made of high resilient, therefore relatively chemically reactive material. The outer concentric washer seal is the true load bearing seal; the inner seal is a means for shielding the load bearing seal from chemical deterioration. A flexible annular metal contactor mounted exterior to the outermost concentric washer seal thermally contacts both juxtaposed parts and maintains thermal equilibrium there between.

Growing community of inventors

Cambridge, MA, United States of America

David C Brown