Abstract: A robot gripper module having a housing pivotally mountable to an end of a robot arm. The housing encloses a first motor for pivoting the housing about a pivot joint, and a second motor operating a rack-and-pinion gear arrangement for extending and retracting fingers. Two opposed groups attached to a rack on opposite sides of a pinion gear. Turning the pinion gear causes the fingers to move toward or away from one another. The motors which may operate independently of the robot arm, may be either servo or stepper motors. The gripper module provides additional degrees of freedom from that of the robot arm, enabling it to work with many kinds of robot arms.

Abstract: A hybrid centrifuge rotor having a rotor core surrounded by a prestressed anisotropic reinforcement ring is disclosed. The rotor core may be made from aluminum and an anisotropic reinforcement ring may be a cylindrical filament wound ring, made from graphite fiber and epoxy resin. The rotor core is manufactured to have a nominally greater diameter than the inner diameter of the reinforcement ring. This rotor core, during the manufacturing process, is subjected to a cryogenic environment where the diameter is shrunk down so that the rotor body may fit and telescope within the reinforcement ring. The rotor body core and reinforcement ring assembly, upon attainment of ambient temperatures, have an interface fit wherein substantial outward force from the rotor body core prestresses the reinforcement ring so that a light weight and strong centrifuge rotor is disclosed.

Abstract: A calibration method and apparatus for economical and rapid calibration of a scientific instrument utilizing a monochromator to generate monochromatic light utilizing controllable means for determining the angular position of a light dispersing element in the monochromator and a filter having a narrow absorption band(s) to determine a relationship between the wavelength of the monochromatic light generated by the monochromator and an angular position of the dispersing element so that the dispersing element can be rotated to an exact position for the monochromator to generate a selected wavelength of monochromatic light.

Abstract: Capillary zone electrophoresis systems are separated into two zones, one primarily for electroosmotic fow generation and the other dominated by electrophoretic effects, by the use of appropriately selected capillary materials for each region. Detection of the solute zones occurs in the electrophoretic region, minimizing or eliminating entirely the entry of the solutes into the electroosmotic region. The benefit acheived is avoidance or minimization of the adsorption of charged solutes by the capillary wall in electroosmotic flow.

Abstract: A measuring system for use with automated pipettes for determining the presence or absence of a pipette tip. The central conduit of the pipette is connected to a source of pressure waves, such as a speaker and also connected to a pressure wave detector, such as a microphone. Changes in acoustic impedance between an open conduit when no tip is present, a partially constricted conduit when a tip is present, and a closed conduit when the liquid boundary layer is contacted determine the measured states of the apparatus.

Abstract: A calibration method and apparatus for economical and rapid calibration of a scientific instrument utilizing a monochromator to generate monochromatic light utilizing controllable means for determining the angular position of a light dispersing element in the monochromator and a filter having a narrow absorption band(s) to determine a relationship between the wavelength of the monochromatic light generated by the monochromator and an angular position of the dispersing element so that the dispersing element can be rotated to an exact position for the monochromator to generate a selected wavelength of monochromatic light.

Abstract: The present invention comprises a method and means for stabilizing the frequency difference between the component frequency modes in the beam of a gas laser influenced by Zeeman splitting. Stabilizing the frequency difference makes constant the frequency of the beat signal obtained from heterodyning the component modes. Stabilization is obtained by accurately controlling the difference in frequency between the component frequency modes to provide a selected separation, preferably 250 KHz, with deviation maintained at less than two KHz. The difference in frequencies is controlled independently of the individual frequency or intensity of either of the component frequency modes, or of their relative position within the "Doppler broadened" spectral profile characteristic of the lasing material.

Abstract: A record of calibration data containing determined values required for accurate operation of a scientific instrument measuring transmissions or absorbance of light in analysis is provided. A method of maintaining and using the records generated by the instrument permits use of the instrument to determine which records are required for efficient and easy instrument usage.

Abstract: An improved mirror alignment control for dynamically aligning the reflecting mirrors bounding the optical path in an interferometer comprises a closed loop servo control which utilizes a two frequency laser beam to provide phase comparison between beams traversing differing portions of the optical paths in the interferometer to determine alignment of the mirrors, said phase comparison providing a correction signal to direct multi-axial alignment of at least one of the mirrors.

Abstract: A centrifuge overspeed protection and imbalance detection system is structured to provide a method for detecting rotor imbalance and rotor overspeed. The system has a single transducer to provide real-time data necessary to detect rotor imbalance and control motor speed.Motor speed is controlled by synthesis of a drive frequency signal for driving the inverter motor control. The drive frequency signal may be inhibited to provide slow acceleration or deceleration, or to shut the motor off by providing a zero slip frequency. Motor control is responsive to a Rotor Identification circuit and operator programming, as well as a closed loop response to the real time tach signal.Imbalance detection is provided by counting tach pulses in each of a plurality of intervals, detecting deviations in tach pulse rate and sounding an alarm when the irregularity of tach pulse signals exceeds the limits of a predetermined standard deviation.

Abstract: A method and apparatus for indicating quench associated with a liquid scintillation solution wherein the solution includes a sample, a solvent and a solute. The method includes exposing the solution to flashes of light, detecting a pulse height spectrum for scintillations produced in the solution in response to the light flashes, determining a unique point on such pulse height spectrum, and relating the unique point to a corresponding pulse height value, such pulse height value providing an indication of quench associated with the solution. The wavelength of light preferably excites essentially only the solvent and the light flash intensity and duration is such that the pulse height spectrum produced in response to the light flashes does not overlap a pulse height spectrum for the sample in the solution. An attribute of the shape of the light pulse height spectrum may be examined to provide an indication of the homogeneous or non-homogeneous nature of the quench present in the solution.

Abstract: A centrifuge adapter is formed in two sections divided by a plane that preferably extends through the longitudinal axis of the adapter. The two sections may be substantially identical in a first embodiment, each including a generally semicylindrical portion having a trough therein and further including an end portion. In a second embodiment, the adapter may comprise a first section including the entire bottom end portion for supporting the bottom of a centrifuge tube. The second section is formed generally as a semicylinder. When the first and second portions are assembled in facing relationship the troughs form a cavity for receiving a centrifuge tube therein. The sections of the adapter may be separate pieces, or they may hingedly connected along a pair of adajcent edges. The sections may be connected by projections extending from one section into corresponding cavities in the other section.

Abstract: A slotted retaining plate for use in a tubular reactor within an analytical system. The reactor contains inert packed material which provides for the necessary flow path length for a fluid stream entering the reactor. The retaining plate is extremely thin and has an array of slots which permit the necessary flow of the stream through the reactor, but retain the packing material within the reactor. The design of the slot array in the retaining plates essentially eliminates any possible impediment to the stream flow. The slots are adjustable to provide more flexibility in slot size control to allow use of smaller packing particles within the reactor and improve the instrument resolution in, for example, an amino acid analyzer.

Abstract: A swinging bucket centrifuge rotor including seating surfaces having shapes which cause buckets seating thereon to be relieved of side loading forces. Each bucket is symmetrical and is pivotally supported by bucket pins that rest in respective spring-loaded carrier assemblies. The spring constants of the springs of the carrier assemblies are selected so that the leading edge of each bucket bottom rests upon a curved surface and clears the respective seating surface before the trailing edge thereof contacts the same. The resulting bucket orientation assures that, upon seating, each bucket rotates until its bucket pins lift slightly off of the surfaces of the respective carrier assemblies.

Abstract: A liquid chromatographic analytical column includes an end cap that is abutted with an end edge of a holder body when the analytical column is fully inserted into a bore in the holder body. An end cap mounted to a precolumn is compressed between the end cap of the analytical column and an end nut connected to a holder union. The holder union has a central passage that admits the precolumn therethrough and a stop that engages a ferrule placed around the precolumn to compress the ferrule against the analytical column end cap to form a seal.

Abstract: A tube-cutting apparatus and method for separating centrifuged materials are shown in which a resilient axial compressive force is exerted on the tube during cutting by spaced tube-holding members; and the cutting knife has flat upper and lower sides against which the severed portions of the tube are held in sealing engagement by the axial force. Independent adjustment is provided for (a) the relative positions of the tube and the cutting knife, and (b) the relative positions of the spaced tube-holding members.

Abstract: Spectrophotometer purge apparatus comprising a sample compartment including a plurality of walls defining a first sample purge volume. The apparatus may further include a volume reducing wall and fastening means for removably fixing the volume reducing wall within the sample compartment to thereby define a second sample purge volume smaller than the first sample purge volume. A purge gas inlet introduces purge gas into the sample purge volumes. Further the apparatus may comprise a movable partition forming one of the plurality of walls and the volume reducing wall. In such an embodiment, the fastening means may further include means for removably fixing the movable partition to thereby define the first sample purge volume. The apparatus advantageously enables the sample purge volume to be adjusted as required to thereby optimize purge efficiency in a spectrophotometer.

Abstract: A transfer mechanism for movement of sample containing vials from a first position to a second position in an analyzer instrument such as a liquid scintillation or a gamma counting device. The apparatus is particularly adaptable where available space is limited. A flexible transport member permits the transformation of movement in one direction into movement in another direction. Sensors and adjusting screws are incorporated into the apparatus for precisely controlling the travel distance of the transport member as well as precisely orienting the direction of the transport member.

Abstract: In a liquid scintillation counter a standard radioactive source is supported within the tubular bore of a flexible coil spring conveyor. Spacer elements within the coil spring retain the source at a predetermined axial position along the spring. The coil spring is disposed in sliding engagement along a conveyor guideway. A drive roller drivingly engages the spring for conveying the source along the guideway between an operating position adjacent the counting chamber and a remote shielded position.

Abstract: A breakaway base for use with an ultracentrifuge rotor wherein the base is designed to fracture when the rotor is above a specified speed so that the rotor will disengage from the drive spindle of the centrifuge. The base has cutout areas to establish a high stress region that is designed to fracture above a specified rotor speed. The cutout areas are designed to receive lugs projecting from the bottom of the rotor. The cutout areas have slotted ledges through which fastening bolts connect to the lugs on the rotor. The fracture of the base in the high stress region in conjunction with the slotted ledges will result in the base fracturing into two parts which will cause rotor disengagement from the drive spindle of the centrifuge and prevent the rotor from spinning at a greater speed.