Patent Application
20100184578
This invention relates generally to centrifuge rotors and, more specifically, to a swing bucket rotor for use in a high-speed centrifuge.
Centrifuges are used to separate components of collected samples of biological and other materials. The samples are typically placed in tubes or other containers configured to be received in a centrifuge rotor for rapid rotation in the centrifuge. One type of centrifuge rotor includes swinging buckets pivotally coupled to a rotor body to permit the longitudinal axes of sample tubes or containers carried on the buckets to rotate from a generally vertical orientation to a generally horizontal orientation as the rotor spins during centrifugation. To balance the dynamic forces experienced during centrifugation, swing bucket rotors are typically designed to support the swing buckets in a generally symmetric arrangement around the rotational axis.
One configuration of a swing bucket centrifuge rotor supports two swing buckets on diametrically opposite sides of the rotational axis of the rotor. Swing bucket rotors of this configuration are commonly referred to as “H-rotors” due to the generally H shape of the rotor body formed by the diametrically opposed spaces for receiving the swing buckets. Exemplary H-rotors include the IEC TWO-PLACE ROTOR for the CENTRA-CL5 CENTRIFUGE, both commercially available from Thermo Fisher Scientific Inc. of Waltham, Mass.
Because centrifuge rotors are rotated at very high speeds during centrifugation, the rotor bodies must be able to withstand the dynamic stresses and forces generated by the rapid rotation of the swing buckets about a central rotational axis. A need therefore exists for improved swing bucket rotors, such as H-rotors, that overcome these and other drawbacks of conventional centrifuge rotors.
The present invention overcomes the foregoing and other shortcomings and drawbacks of swing bucket rotors, such as H-rotors, heretofore known for use for centrifugation. While the invention will be discussed in connection with certain embodiments, it will be understood that the invention is not limited to these embodiments. On the contrary, the invention includes all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention.
In one aspect, 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. In one embodiment, the reinforcing material comprises carbon fiber material. In another embodiment, the rotor body comprises carbon fiber laminates.
In another aspect, a method of making a centrifuge rotor includes locating first and second pairs of bucket supports on a rotor body for pivotally supporting first and second swing buckets on diametrically opposed sides of the rotor body. Reinforcing material is wound around one of the first pair of bucket supports and an oppositely disposed one of the second pair of bucket supports. Reinforcing material is also wound around the other of the first pair of bucket supports and the other one of the oppositely disposed second pair of bucket supports. In one embodiment, the reinforcing material comprises resin-coated carbon fibers.
The above and other objects and advantages of the present invention shall be made apparent from the accompanying drawings and the description thereof.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given above, and the detailed description given below, serve to explain the invention.
Referring to the figures,
With continued reference to
In one embodiment, the rotor body 20 may be formed from resin-coated, carbon fiber sheets or laminates that have been stacked and compression molded to form a unitary structure. The compression molded rotor body 20 may further include metallic inserts defining portions of the rotor body 20, such as portions of the central hub 22. It will be appreciated that various other materials and methods may be used to form the rotor body 20. For example, the rotor body 20 may alternatively be formed, wholly or in part, from polymers, metals including steel, titanium, or aluminum, or from various other materials suitable for forming a rotor body for use in centrifugation.
A first pair of bucket supports 40a, 40b is provided on the first arms 30a, 30b, and a second pair of bucket supports 40c, 40d is provided on the second arms 34a, 34b for pivotally supporting the first and second swing buckets 12a, 12b, respectively, in the first and second bucket receiving spaces 32, 36 of the rotor body 20. In the embodiment shown, each bucket support 40a, 40b, 40c, 40d comprises a pin 42 having a longitudinal axis 44 aligned substantially parallel with a longitudinal axis 46 of the central hub, and a bushing or trunion 48 coupled to the pin 42. It will be appreciated that the bucket supports 40a, 40b, 40c, 40d may alternatively comprise various other structure suitable for pivotally supporting swing buckets 12a, 12b within the bucket receiving spaces 32, 36. As non-limiting examples, the bucket supports 40a, 40b, 40c, 40d may alternatively comprise pins without trunions, or may comprise structure defining journals for receiving corresponding pins structure associated with a swing bucket 12a, 12b. When the rotor body 20 is formed from compression molded carbon fiber material, or other moldable materials, the bucket supports 40a, 40b, 40c, 40d may be integrally molded with the rotor body 20. Alternatively, the bucket supports 40a, 40b, 40c, 40d may be secured to the rotor body 20 using adhesives or any other suitable process for securely mounting the bucket supports 40a, 40b, 40c, 40d to the rotor body 20.
With continued reference to
While reinforcing material 50 has been depicted herein being wound around bucket supports 40a, 40b, 40c, 40d and arms 30a, 30b, 34a, 34b in a sequential operation, it will be appreciated that reinforcing material 50 may alternatively be simultaneously wound around the opposed pairs of bucket supports 40a, 40b, 40c, 40d and arms 30a, 30b, 34a, 34b.
In one embodiment, the reinforcing material 50 comprises resin-coated carbon fiber tows, such as 24K carbon fiber tows commercially available from Toray Industries, Inc. of Tokyo, Japan. After the carbon fiber tows have been wound around the respective bucket supports 40a, 40b, 40c, 40d and arms 30a, 30b, 34a, 34b as discussed above, the reinforcing material 50 may be cured by applying heat and/or pressure to the carbon fiber wound rotor body 20 to form a substantially integral structure.
Referring now to
With reference to
While various aspects in accordance with the principles of the invention have been illustrated by the description of various embodiments, and while the embodiments have been described in considerable detail, they are not intended to restrict or in any way limit the scope of the invention to such detail. The various features shown and described herein may be used alone or in any combination. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the scope of the general inventive concept.
