Hewlett-packard Company

Agilent Technologies, Inc.

H Bryan Bente

Joel Myerson

Robert C Henderson

Andrew Stefanski

Michael D Glaser

Alan C Herman

Benjamin G Shaw

An electro-mechanical variable fluid flow restrictor includes a support having a passage and a seal surface, a deformable seal that is engageable with the seal surface, and a bias member for exerting an electronically controlled variable bias against the deformable seal. The seal surface includes channels formed in its surface that extend beneath the deformable seal. The bias member can exert a bias sufficient to cause the deformable seal to fill the channels, preventing fluid flow through the channels. When the bias member decreases the bias against the deformable seal, the deformable seal gradually moves out of the channels, allowing fluid flow through the channels, and through the passage in a flow control. The deformable seal does not need to separate from the seal surface to allow fluid flow. Instead, fluid flows through the small, controlled flow areas created when the deformable seal withdraws from the channels.

Flow control providing stable fluid flow

A device for performing sample acquisition and introduction of a selectable quantity of the acquired sample to associated device such as an analytical instrument. The preferred embodiment of a the device includes a reservoir for reserving a quantity of sample, a sipper section having a nozzle for inserting an exposed orifice extending therefrom into a sample aggregation, a pump for forcing a quantity of sample from the sample aggregation through the nozzle and into the reservoir, a metering section having a selectably operable motive force unit and a metering unit for withdrawing a sample quantity to be analyzed from the reservoir and for causing the withdrawn sample quantity to be metered into at least one discrete sample quantity of selectable volume, a vaporization section having a vaporizing chamber for receiving the discrete sample quantity and a vaporizer for optionally causing the volatile components of the discrete sample quantity to be volatilized, and an interface which is connected to the vaporization chamber and adapted for insertion into the carrier fluid stream of the instrument. The vaporization chamber may be pneumatically coupled on demand to a carrier fluid stream whereby the metered or volitalized sample components may be rapidly introduced to the carrier fluid stream so as to effect a sample component/carrier fluid mixture.

Cartridge system for effecting sample acquisition and introduction

A plurality of different liquid solutions are connected to an input of a pump system having at least two displacement chambers and in a manner to control the proportions of each constituent that are taken into each chamber during its intake stroke. The outputs of the chambers are connected to a common liquid output. The chambers are driven by independently controllable motors so that the discharge stroke may be chosen to have some parameters, such as speed profile and duration, that are different than during the intake stroke. As a result, both chambers may simultaneously discharge liquid through the common output, if desired. The proportion of constituents may be made different each time one of the chambers is filled, so the simultaneous discharge of the chambers allows a gradual, carefully controlled change from the mixture of one chamber to that of the other. Thus, the pump system can be operated to provide a combination of low pressure and high pressure mixing of two or more liquid constituents in order to provide a smooth gradient in the output liquid flow. Output liquid flow rate can be controlled by changing the time in which the chamber's volume is reduced, or by controlling the maximum volume of the chamber's displacement, or both. Such a pumping system is especially useful in providing a solvent mixture with a gradually changing composition to a liquid chromatograph column.

Fluid proportioning pump system

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Landenberg, PA, United States of America

H Bryan Bente