Abstract: A swinging bucket centrifuge rotor having a plurality of cavities spaced about its vertical axis and extending entirely through the rotor. Each cavity is adapted to receive a bucket supported by a hanger rod. The mounting of the bucket is such that the bucket can pivot or swing from a vertical to a horizontal position during operation. Each cavity is provided with a slot, which extends along the underside of the rotor, from the cavity to the periphery of the rotor. The slot has an upper surface adapted to receive the bucket when the bucket is in the horizontal position. A pair of opposed grooves extend partway down the wall of the cavity whereby the ends of the grooves each form a ledge to support an end of the hanger rod by which the bucket is pivotally suspended.

Abstract: A centrifuge rotor is provided which has a circumferential wall and a plurality of spaced arms which radiate outward from the center to the circumferential wall. A plurality of buckets are mounted on the rotor, one between each arm. Each bucket has two outwardly extending pivot pins situated on a common axis. A plurality of hangers are mounted in the spaced arms of the rotor. Each hanger comprises an elongated housing containing an opening which is transverse to the longitudinal dimension of the housing for receiving the pivot pin of a bucket. A longitudinal bore intersects the opening and contains a spring for exerting a clamping force on the pivot pin when the rotor is stopped. This prevents the bucket from rocking when being loaded or unloaded, but does not prevent the bucket from pivoting to a horizontal position when the rotor is rotating, nor does it prevent the bucket from resuming a vertical position when the rotor is stopped.

Abstract: A centrifuge tube holder capable of being manually assembled and disassembled without separate tooling to provide not only ease of cleaning, but also interchangeability of parts to accommodate various sized centrifuge tubes. The tube holder arrangement provides proper support with a minimum of parts to create a lighter weight assembly for use in a centrifuge rotor.

Abstract: Bargraph displays wherein the illuminable bar segments are formed by winding filamentary conductors upon a mandrel.

Abstract: An integrating analog-to-digital converter for converting an input signal having an amplitude representing an analog quantity into a digital signal representing the quantity wherein the input signal may have either a positive or negative polarity and the converter automatically generates the digital signal without regard to such polarity. The converter uses a single circuit for charging and discharging a capacitor such that any errors or offsets occurring upon charging are fully and automatically compensated for during discharging so as to provide for automatic zeroing of offset errors without separate autozeroing circuitry.

Abstract: A centrifuge holder to inhibit movement of a centrifuge machine caused by a rotor within the centrifuge coming off the drive spindle. The holder apparatus is designed in such a manner that the centrifuge machine can be placed on or removed from the holder without the need of any separate tool. Tab members of the holding apparatus are received within spaced apertures located in the bottom of the centrifuge.

Abstract: A fixed angle tube carrier is provided for use with externally shouldered sample tubes and a centrifuge rotor having formed therein a plurality of symmetrically disposed vertical slots in its outer peripheral surface. The slots are formed in the shape of a "T" and adapted for sliding engagement with a tube carrier. The tube carrier comprises a vertically elongated member having a "T" shaped cross-section which is adapted for sliding engagement with the slots of the rotor. The carrier contains a plurality of circular recesses which are open at each end and adapted for holding an externally shouldered sample tube. The longitudinal axis of each recess is disposed radially of the vertical axis of the rotor and at an angle less than 90.degree. thereto.

Abstract: A circuit for measuring the root-mean-square (RMS) value of an electrical signal. The output may be linear or logarithmic. The circuit uses devices with logarithmic voltage/ current characteristics (usually transistors), and allows the logarithmic devices to be connected directly together without intervening operational amplifiers. In its simplest form, the invention consists of a rectifier circuit, four transistors and a capacitor.

Abstract: A centrifuge rotor for carrying a plurality of centrifuge tubes at a fixed angle with respect to the spin axis of the rotor wherein the rotor has a containment annulus located above the tube cavities in the rotor for containment of any excess fluid from the centrifuge tubes during centrifugation. The containment annulus is designed in such a manner that it will receive all possible excess fluids from the centrifuge tubes during centrifugation and none of the excess fluid will contact or exert pressure on the rotor lid.

Abstract: A method and apparatus for monitoring flow rate through a conduit. A flow number indicative of the flow rate of a liquid through the conduit is compared with a preselected reference number. The actual liquid flow through the conduit provides a clocking signal which determines the time span during which a count signal, indicative of the intended flow rate into the conduit, is accumulated thereby providing the flow number.

Abstract: A sealed bowl rotor having a transparent lid for easy visual checking of rotor contents. The lid has sealing means that automatically creates a seal which prevents the escape of liquid samples from within the rotor when the lid is placed on the rotor. The rotor design prevents the application of any possible hydraulic loading on the transparent lid. The installing/removing mechanism on the lid provides the capability for removal of the lid after the centrifugation run without disturbing the contents of the samples within the rotor.

Abstract: A centrifuge rotor and sample containers for reorienting gradients and separating the components of a sample. The rotor contains a plurality of cylindrical recesses equally spaced about its rotational axis. The recesses are open at the top and have a concave hemispherical bottom. A cylindrical plug member is positioned in each of the recesses, and the lowermost end of the cylindrical plug member is formed in the shape of a concave hemisphere. A sample container in the shape of a hollow sphere is positioned between the hemisphere of the cylindrical plug member and the hemisphere of the recess bottom, and means are provided to retain the cylindrical plug member in the recess. The symmetry of the hemispherically shaped sample container is advantageous for minimizing any disturbance to a gradient during reorientation. In another embodiment, a centrifuge rotor is provided which is adapted for fixed angle centrifugation with hemispherical sample containers.

Abstract: A centrifuge rotor having an internal chamber in which are mounted a plurality of swinging centrifuge tubes containing fluid samples. Located within the rotor chamber is a liquid support medium which minimizes the amount of stress experienced on the centrifuge tube and at the pivotal junction of the tube with the rotor. The unique arrangement of having the buoyant force of a liquid within the rotor provides support to the tubes when the tubes have pivoted to their position during operational speed. The liquid support is designed to reorient in response to centrifugation in order to automatically provide the buoyant force to the tube during centrifugation and thereby reduce or greatly minimize the strength necessary in the mechanical design and construction of the support elements for the swinging tubes or containers.

Abstract: A method for making a thin wall centrifuge tube using an injection blow molded process to achieve not only uniform thickness of the tube, but also uniform or homogeneous material properties throughout the tube structure. The unique application of this process includes the making of a preform mold which retains its molten stage on a transferrable core pin that is received at a second stage, where the final configuration mold is placed around the core pin. The blow molding stage operates in conjunction with the molten preform to create the high strength centrifuge tube with uniform material properties.

Abstract: A transparent tube for use in the cavity of the rotor of a high speed centrifuge. The tube is penetrable at its bottom end by a needle of a hypodermic syringe. The tube is open at the top and has a rounded bottom with an opening forming a passageway therein. A recess forming a shoulder co-axial with the passageway is provided both on the inner side and the outer side of the tube. A resilient plug having flanges at each end provides a tight fitting closure for the passageway and recesses.

Abstract: An electro-mechanical package is disclosed which includes an LCD and an IC chip mounted on opposite sides of a PC board by common package-retaining means, which includes posts extending through the PC board and a clip member that latches onto the ends of the posts to retain the package in assembled position. The latching action is resilient and permits non-destructive disassembly.

Abstract: The present invention provides a centrifuge rotor adapted for continuous separation of specific particles from mixed populations thereof by a process of centrifugal elutriation. In the rotor, elutriation cells abut a central spindle having fluid carrying means, and thereby eliminate intermediate conduits and seals therefor, thus reducing the likelihood of leakage because of faulty aperture registration or failure of the sealing means.

Abstract: In accordance with the present invention, there is provided an air driven centrifuge having an access door to a rotor chamber housing a rotor seat and a rotor having a plurality of turbine flutes formed in the underside thereof. Air jet means in the rotor seat are provided for supporting and spinning the rotor on an air cushion in the chamber. Means are provided to prevent the opening of the access door when pressurized air is supplied to the air jets, and means are provided to delay for a predetermined period, the opening of the door after the supply of pressurized air to the air jets is discontinued.

Abstract: The present invention is directed to a transparent safety cover for sealing the mouth of a pivotally mounted bucket of a centrifuge rotor. The cover has a first surface configured to make telescoping engagement with the sidewall of the rotor bucket. A shoulder adjacent the first surface abuts the top of the bucket to limit the length of engagement. The first surface has an annular groove containing a resilient O-ring which makes a seal between the cover and the bucket. In the upper portion of the cover, there is a raised dome-like structure with a circular aperture at the top. The aperture has inverted conical walls and is sealed by a movable, resilient, sealing plug. The plug has a tapered body and at the lower portion thereof, are wall gripping means for retaining the plug in a raised, unseated, position. With the plug in the unseated position, the bucket is vented to the atmosphere permitting telescoping movement of the cover with respect to the bucket.

Abstract: A rotor seat which automatically adjusts its position with respect to the rotor in response to air flow levitation air entering between the rotor and the rotor seat. The central portion of the rotor seat which has a mating design with the design of the bottom of the rotor is free to move in a vertical direction toward or away from the rotor in response to the flow of air. The rotor seat maintains its optimum position relative to the rotor, allowing the rotor to decelerate in a stable manner.