Abstract: A manually operated actuator is described with which small incremental motions of a rod are obtained to advance a piston of a prefilled syringe. The device employs a reciprocally actuated drive element with a hole through which the rod passes freely when the drive element is in a release position. When the drive element is pivoted to a rod engaging position a pair of edges formed by the hole engage the rod and advance it an increment depending upon the amount of linear movement of the drive element. A back-up inhibitor is employed to prevent the rod from moving back when the drive element is returned to a release position. The back-up inhibitor is syringe responsive by employing a mechanism which causes engagement of the rod by the inhibitor when a syringe is attached to the actuator housing. A syringe with specially adapted flanges is described for use with the actuator.
Abstract: An automatic pipette is described which can be manually held yet provides a highly accurate instrument capable of precise handling of very small liquid samples. A main housing is provided sized to be conveniently held in the hand of an operator. The housing encloses a displacement mechanism of a size selected to provide a highly accurate handling of small liquid samples as well as a motor drive, control circuit and a power source. The control circuit provides a precise control over rate of intake and dispense and is selected to reduce power demand while maintaining safety features to simplify operator manual control. A technique is described to enhance engagement between the pipette and a replaceable tip for low air leakage and attendant enhanced take-up accuracy, as well as provide an integral method for gentle tip removal after contamination. A dilution pipette is described to provide a highly accurate dilution of small liquid samples.
Abstract: A replaceable pipette tip is described which forms a tight sealing engagement with the working end of a pipette. In one embodiment for a pipette tip a cam surface is provided to enable a slight tip rotation when the working end of a pipette is inserted in the tip. A particularly effective and reliable seal is obtained when a pipette tip having integrally molded ring seals and a cam surface is employed with a pipette working end having a resilient insert located to form an effective seal with the molded rings.
Abstract: A valve is described capable of rapid actuations. The valve includes a drive element disposed to pinchingly engage a collapsible tube at a high reciprocating speed. A follower is disposed on the other side of the tube and effectively coupled for reciprocation and cooperative movement with the drive element to maintain the tube pinched off. Control means and holder are provided to open the valve by retaining the follower at just that time when the follower is at a favorable reciprocated position so that further reciprocation by the drive element can open the tube. A normally open valve is also described and a control for operation of a plurality of valves is disclosed.
Abstract: A method and apparatus for dispensing small quantities of viscous materials in a reliable and accurately repeatable manner are described. A deformable tube which couples material in a reservoir to a discharge port is pinched by a valve at the same time the reservoir is pressurized. The material is dispensed in correspondence with the amount of reduction of the tube volume by the pinch valve. A simultaneous depressurizing of the material in the reservoir and the opening of the pinch valve enables a suck-back for a crisp cut-off of the material.
Abstract: An actuator for a syringe is disclosed with which precise liquid quantities can be dispensed in an accurately repeatable manner with single-hand control. The actuator is formed with a main body shaped to support a syringe whose plunger is moved by a plunger actuator. A reciprocating finger actuatable pusher is mounted with the plunger actuator to the main body and a ratchet mechanism operative between the plunger actuator and the pusher provides discrete motions of the plunger actuator. The main components of the syringe actuator are formed of extruded material and shaped in cross section to conveniently fit together. A back motion inhibitor is employed in the form of a fibrous material capable of restraining reverse movement of the plunger actuator while allowing unobstructed operative movement thereof.
Abstract: A material dispenser using a deformable tube through which the flow of material is controlled is described. The deformable tube is selectively mounted to expose a pinch region to a pressure element having a predetermined shape. The deformable tube is selectively supported to enable precise control over tube constriction for accurate material flow control. A micrometer stop is conveniently mounted to regulate the size of the tube restriction. Automatic and repeated actuation of the dispenser is obtained by locating the pressure element as a piston in a cylinder. Various deformable tube embodiments are described to reduce tube wall stresses for longer operating life and enable both positive closure and opening of the deformable tube.
Abstract: Disclosed herein is a polymer comprisingA. from about 1 to 100% by weight of a polymerized monomer containing at least one active methylene group and having the formula ##EQU1## wherein n is 0 or 1, R is hydrogen or methyl, R' is substituted or unsubstituted arylenethylene having the structure ##EQU2## wherein Ar is arylene, R.sup.2 is hydrogen, alkyl, aryl, or cycloalkyl, R.sup.3 is alkoxy or amino when n is equal to 0, and R.sup.3 is alkyl, alkoxy, amino, cycloalkyl or aryl when n is equal to 1; andB. from 0 to about 99% by weight of at least one additional polymerized ethylenically unsaturated monomer.