Piramoon Technologies, Inc.

Beckman Instruments, Inc.

Fiberlite Centrifuge LLC

Other

Alireza M Piramoon

Sina Piramoon

Robert Wedemeyer

Michel Mark Fournier

David Sebio

Thomas D Sharples

Robert S Carey

Rebecca J Woodruff

Don Fritsch

Guillaume Crete

A centrifuge rotor is provided having a rotor core that defines a rotational axis of the rotor. A plurality of bucket supports is arranged about the axis of rotation. The rotor includes first and second straps that respectively wrap around two diametrically-opposed ones of the bucket supports for restricting outward movement of the two bucket supports relative to the rotor core. The first and second straps intersect one another at a location through the axis of rotation of the rotor.

Fiber-reinforced swing bucket centrifuge rotor and related methods

A centrifuge rotor includes a rotor body having a central hub and first and second bucket receiving spaces defined on diametrically opposed sides of the rotor body. A first pair of bucket supports is supported by the rotor body for pivotally supporting a swing bucket in the first bucket receiving space, and a second pair of bucket supports is supported by the rotor body for pivotally supporting a swing bucket in the second bucket receiving space. The rotor further includes reinforcing material wound around oppositely disposed ones of the first and second pairs of bucket supports.

Method of making a composite swing bucket centrifuge rotor

A centrifuge rotor includes a rotor body having first and second axial ends and a circumferential sidewall extending therebetween. The rotor body has a plurality of wells for receiving sample containers to be processed in the rotor. The rotor further includes an elongate reinforcement extending around the circumferential sidewall of the rotor body along a helical path. At least two portions of the elongate reinforcement interlock at one or more specific points on the surface of the rotor.

Method of making a fixed angle centrifuge rotor with helically wound reinforcement

A bucket is provided for use with a centrifuge rotor. The bucket includes a bucket body that has a side wall and a bottom wall. A pair of projections extend from the side wall on opposing sides of the bucket body and are configured for engagement with the centrifuge rotor. The bucket also includes reinforcing material coupled to the projections for restricting movement of the bucket body relative to the projections during centrifugation on the centrifuge rotor. The projections may include bushings that extend outwardly from the side wall for engaging corresponding pins on the centrifuge rotor. The projection may alternatively or additionally include pins for engaging corresponding journals on the centrifuge rotor. The bucket body may include a pair of diametrically opposed apertures, with each of the projections extending through one of the apertures.

Reinforced swing bucket for use with a centrifuge rotor

Composite centrifuge rotor

Fixed angle centrifuge rotor with helically wound reinforcement

A compression molded fixed angle carbon fiber centrifuge rotor and method for forming the centrifuge rotor are provided. My prior art technique of compression molding is utilized in which a frustum fixed angle rotor body is formed between mold parts. As before, sample tube aperture cores are clustered from the apex end of the mold in that array which duplicates the intended number, size, and angularity of the sample tubes desired in the finished rotor. The bottom boundary of the rotor mold has no longer has a substantially planar boundary; instead the bottom of the rotor mold is supplied with a series of scallops, these scallops being equal in number to the sample tube aperture tubes. The shape at the bottom boundary of the rotor is maintained to give a substantially uniform thickness between the sample tube apertures and the exterior bottom surface of the rotor. Sufficient thickness of material is maintained to resist natural load of sample within the sample tube apertures.

Process for compression molding a composite rotor with scalloped bottom

In a fixed angle centrifuge having sample tube apertures symmetrically distributed around the spin axis of a rotor body, two rotor body shapes are disclosed at the rotor body top adjacent the openings to the sample tube apertures. These shapes each permit both release of the sample tube aperture cores and maintain the intersection of the top of the sample tube aperture within a plane normal to the axis of the sample tube aperture. A first shape includes placing discrete facets at the top of the rotor body adjacent the sample tube aperture openings. The second, and preferred embodiment, includes generating a spherical surface utilizing a spherical radius which is taken from the intersection of the spin axis of the rotor and the axes from each of the sample tube apertures. In both cases, precise termination of material molding the rotor body occurs at the top of the cylindrical portion of the sample tube aperture. Sample tube aperture core withdrawal easily occurs. Further, the ultimately formed sample tube aperture easily supports the sample and sample tube during centrifugation.

Process for making a net shaped composite material fixed angle

Composite fibers are woven into helical fabric strips. These helical fabric strips wind upon one another as a helix to form a cylinder. When the helical strips are impregnated with resin, heated to the thermoset temperature of the resin, and compressed and cured, a cylindrical composite body results having the individual fibers of the body only arrayed radially or circumferentially. This structure can then be provided with sample tube apertures, usually after curing the cylindrical structure. Dependent upon the rate of differential advance of the weft threads, the woven cloth helically stacks to a cylinder of variable diameter--usually about a cylindrical central aperture in the cylinder.

Helically woven composite rotor

In the compression molding of a fixed angle centrifuge rotor utilizing discontinuous fibers, sample tube apertures cores present in the net-shape mold are covered with pre-cured sample tube aperture inserts. The sample tube aperture inserts have a constant and unchanging inside diameter and are formed from composite fiber. This composite fiber extends from the closed bottom of the inserts, upwardly along the sides of the inserts to the open top of the inserts to provide tensile strength longitudinally of the sample tube aperture inserts. The sample tube aperture inserts have a regular and smooth inside for first accommodating the sample tube aperture cores when the rotor is compression molded and later the sample tubes themselves when the rotor is fully fabricated. These inserts have an irregular outside for forming an interference fit with the subsequently formed compression molded rotor body. Finally, the sample tube aperture inserts have a tapered thickness with the top and open portion of the inserts having a thick wall construction and the bottom and closed portion of the inserts having a thinner wall construction. In use, and when the compression mold is loaded, the sample tube aperture inserts are placed over the sample tube aperture cores. When the mold is fully loaded, and compression molding occurs, the inserts integrally form to the rotor body and the sample tube aperture cores are removed.

Method for compression molding a fixed centrifuge rotor having sample

A method for the compression molding of composite fiber fixed angle rotors is disclosed. A female mold member defines a closed cylinder cavity for molding the bottom surface of the rotor, this cavity usually defining a frustum shaped central cavity complimentary to and concentric with the spin axis of the ultimately formed rotor. A male mold member having a complimentary cylindrical profile contains a frustum shaped inner cavity with the apex of the frustum disposed to the inner portion of the cylinder and the base end of the frustum exposed to the cylindrical opening of the female mold. This frustum shaped inner cavity defines the exterior frustum shape of the ultimately produced rotor and defines between the exterior frustum profile and the frustum shaped inner cavity a rotor body wall having sufficient thickness to receive the sample tube apertures. At the apex end of the frustum shaped cavity in the male mold member, there is located a lock system for maintaining sample tube aperture cores. These sample tube aperture cores are locked within the frustum cavity in the precise alignment of the ultimately formed sample tubes of the rotor. Loading of the mold with resin pre-impregnated fiber typically occurs in the frustum shaped cavity of the male mold member and at the bottom of the female mold member. A compression molded rotor product is MANUFACTURED having discontinuous fibers optimally disposed to resist the forces of centrifugation.

Method for compression molding a composite material fixed angle rotor

A method and apparatus for the compression molding of composite fiber fixed angle rotors is disclosed. A female mold member defines a closed cylinder cavity for molding the bottom surface of the rotor, this cavity usually defining a frustum shaped central cavity complimentary to and concentric with the spin axis of the ultimately formed rotor. A male mold member having a complimentary cylindrical profile contains a frustum shaped inner cavity with the apex of the frustum disposed to the inner portion of the cylinder and the base end of the frustum exposed to the cylindrical opening of the female mold. This frustum shaped inner cavity defines the exterior frustum shape of the ultimately produced rotor and defines between the exterior frustum profile and the frustum shaped inner cavity a rotor body wall having sufficient thickness to receive the sample tube apertures. At the apex end of the frustum shaped cavity in the male mold member, there is located a lock system for maintaining sample tube aperture cores. These sample tube aperture cores are locked within the frustum cavity in the precise alignment of the ultimately formed sample tubes of the rotor. Loading of the mold with resin pre-impregnated fiber typically occurs in the frustum shaped cavity of the male mold member and at the bottom of the female mold member. A compression molded rotor product is disclosed having discontinuous fibers optimally disposed to resist the forces of centrifugation.

Compression mold for forming a composite material fixed angle rotor

A fixed angle centrifuge rotor body is constructed from compression molded composite material. The rotor body has a frustum shaped peripheral contour about a central spin axis between a base end and an apex end. The body has net shaped angled sample tube apertures defined in the rotor body extending from openings in the apex end adjacent the spin axis of the rotor body to bottom portions of the sample tube apertures more remote from the spin axis of the rotor body. The rotor body is formed from resin cured about discontinuous composite fiber with the major axis of the discontinuous fiber disposed normal to the spin axis of the rotor body interior of the rotor body. The resin cured discontinuous composite fibers exceed 40 weight percent of the cured rotor product and have no visible layering between respective fibers. The resin cured discontinuous composite fibers have minor vertical excursion parallel to the spin axis of the rotor and relatively no kinking along their respective lengths. The resin cured discontinuous fibers are disposed parallel to the surfaces of and about molded sample tube apertures in the rotor body.

Compression molded composite material fixed angle rotor

A fixed angle rotor and method of manufacture of a fixed angle rotor has a frustum shaped rotor having rounded surfaces reinforced by filament tow windings against both vertical and horizontal forces generated during centrifugation. A so-called 'high speed' rotor has a bottom composite disc, a top composite disc, and a frustum shaped hollow fiber reinforced molded insert between the respective discs having a stepped exterior surface. An 'ultra speed' rotor has a bottom composite disc, a top composite disc, and composite discs therebetween defining a stepped exterior surface. In both cases, these exterior steps have surfaces which capture the windings to the exterior of the rotor. A first class of individual fiber windings about the rotor is applied having a vertical reinforcement component parallel to the spin axis and normal to the laminate layers. These windings include either vertically disposed loops in grooves on the stepped exterior of the rotor which tie the top and bottom discs together (with the remainder of the rotor securely sandwiched therebetween) or vertically disposed windings in exterior grooves which extend over both top and bottom discs of the rotor. A second class of windings includes circumferential windings on the step surfaces of the rotor. Such windings are applied to fill in the stepped surfaces as well as to resist centrifugal forces of centrifugation.

Fixed angle composite centrifuge rotor fabrication with filament

An automatic lay-up machine is disclosed for composite material article having anisotropic resistance in tension. A layer of fiber material, either unidirectional or fabric weave, is dispensed between a supply roll and a take-up roll. This material is advanced over a cutting table having at least one and preferably a plurality of cutting molds, each mold cutting a profile of a portion of an article being fabricated and leaving a continuous scrap webbing for gathering at the take-up roll. The material is placed under tension across the cutting table, compressed, and cut at the molds to extract the individual layers having the desired sections utilized in fabricating the article. This process is repeated with the molds indexing in rotation with respect to the material so that successive layers filling the molds align their respective fibers in varying directions. Sufficient scrap material is left between the cutting table and the take up roll that tension can be drawn through the un-severed fiber sections as material is sequentially advanced across the cutting table. Where pre-impregnated composite tape or fabric are used, refrigeration of the supplied tape with following adhering to form a unitary article or article part occurs. Alternately, built up layers of composite layers without resin can be impregnated with resin. This article or article part is then cured as a unitary mass.

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Santa Clara, CA, United States of America

Alireza M Piramoon