Imperforate bowl: centrifugal separators – Rotatable bowl – Driven by energy of material supplied
Reexamination Certificate
2000-03-06
2001-05-01
Cooley, Charles E. (Department: 1723)
Imperforate bowl: centrifugal separators
Rotatable bowl
Driven by energy of material supplied
C494S079000
Reexamination Certificate
active
06224531
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention relates to a rotor which is suitable especially for installation in a free-jet centrifuge.
Such rotors are disclosed, for example, in DE OS 2 532 699, wherein a rotor for a centrifugal cleaning device with a high hub, through which the liquid to be cleaned is fed to inlet openings which are connected with the interior of a rotor chamber, the liquid escaping from one end of the interior of the rotor chamber through one or more reaction nozzles which are so arranged that the rotor is set in rotation, the interior of the rotor being divided by an annular dividing wall into two chambers, namely into a relatively large inlet chamber with which the inlet openings are in communication, as well as a relatively small outlet chamber adjoined by the nozzles, and the inlet chamber and the outlet chamber are connected to one another by an overflow channel which surrounds the hollow hub at a small distance away. Such an apparatus has a great weight and is expensive to manufacture.
Also a rotor is disclosed in DE PS 4014440 for a laboratory centrifuge, which has a plurality of injection molded synthetic resin parts and which has a symmetry with a vertical shaft which simultaneously forms the axis of rotation, such that it is divided circumferentially into a plurality of sectors of identical construction, the sectors having a plurality of radial projections and flat parts running circumferentially, which has a plurality of receptacles for test tubes running radially to the axis of rotation and at an angle. Such an apparatus is not suitable for use as a flow-through centrifuge.
Also a rotor is disclosed in EP A2 608 519 which contains a loosely flexible synthetic resin container for receiving red blood corpuscles, which is by a rotor housing receptacle of metal which absorbs the static forces. In this embodiment the main emphasis is on the creation of a removable, biocompatible container for human secretions to be centrifuged, especially, for example, for separating red blood corpuscles and plasma, wherein the separated blood corpuscles are then removed and purified. This apparatus has a very limited application with regard to the media to be centrifuged.
It is a disadvantage of the known apparatus of the kind described above that they are heavy, expensive, and unsuitable for high rates of throughput, and are not usable for cleaning, for example, a stream of motor oil with its correspondingly high temperatures.
SUMMARY OF THE INVENTION
The present invention, therefore, is addressed to the problem of improving an apparatus of the kind described above so that a rotor will be created which will be safe and reliable in operation, especially as regards throughput and separation boundary, while paying attention to the matter of easy disposal after the end of its useful life.
According to the invention, the problem is solved by a rotor with at least one inlet and at least one outlet for the medium being centrifuged, wherein the rotor has at least one bearing point to receive a bearing element and consists substantially of self-supporting synthetic resin.
Normally, the rotor is installed in an enclosure of a free-jet centrifuge. But it is also conceivable to install it directly into the oil pan of an internal combustion engine.
A weight reduction can be achieved by the use of synthetic resin. In addition, the use of, for example, injection molded parts also offers a considerable cost advantage. Synthetic resins today offer great versatility. They can withstand high temperatures up to about 140° C., which is the case with motor oil, especially when the internal combustion engine in which such a centrifuge can be employed is operated under extreme conditions.
The use of synthetic resin material, however, offers an additional important advantage. It makes it possible to provide guiding elements in the interior of the rotor in an economically reasonable manner.
By extending the guiding elements from the inner hollow hub to the outer wall of the rotor on the one hand, and extending the guiding element from the side of the rotor head facing away from the rotor bottom down to the rotor bottom inside of the rotor housing, the medium being centrifuged is subjected to a positive guidance which, depending on the rotor speed, makes it possible to set a defined boundary of separation with respect to the particles that are to be removed. It is basically also possible to provide guiding elements in sheet metal rotors. This version, however, is not as economical to manufacture.
The outlets configured as nozzles in the rotor assure that the fluid will flow out in a tangential direction with respect to the axis of rotation of the centrifuge. The outlets, however, can be aimed downwardly, in which case a component of force acting against gravity develops on the rotor, which relieves the bearings of the rotor.
In an advantageous embodiment of the invention, the distance of the outlet from the axis of rotation is greater than the outside radius of the rotor. In this manner it is assured that the medium can exit really tangentially from the nozzle, which represents an increase in performance in comparison with the state of the art, on the one hand, and on the other hand starting up is positively influenced and the running speed is substantially more stable.
Also provision can be made according to the invention for providing elements on the outside wall of the rotor to stiffen it in the direction of the main tension axes. This counteracts the flow behavior of the synthetic resin. The guiding elements provided inside of the rotor likewise perform a stiffening function.
In case of a possible use as a mainstream centrifuge, it proves advantageous, especially in low speed ranges, to support the rotor positively with an external drive in order to assure the desired particle size limit, which depends directly on the speed of the rotor. A stable and creep-resistant mounting proves in this case to be advantageous.
A practical embodiment of the invention provides a ball bearing at least at one of the pivots of the rotor. In this manner the start-up performance of the turbine can be improved. Furthermore, the ball bearing can accommodate the axial forces of the rotor which fluctuate according to the state of operation of the centrifuges.
In another advantageous embodiment, the rotor housing has a centrifuge shaft as the mounting element. The use of a shaft made, for example, of steel makes possible a very precisely working mounting in connection with a centrifuge spindle and the corresponding bearings, so that it is possible to use the centrifuge as a mainstream centrifuge without a preceding or following oil filter.
It is advantageous to make the rotor entirely of synthetic resin. This can be accomplished by casting its pivots in one piece with the rotor. This has the positive effect of reducing the number of parts in the centrifuge and enabling the rotor to be disposed of by burning when it is replaced.
The rotor shell and rotor base can be joined together advantageously by snap fastening. Simplification of assembly is thereby achieved. Another possibility is to weld the rotor head and rotor bottom together. The vibration welding method is especially suitable for this purpose, but the rotation welding method, for example, is also conceivable.
In another variant of the invention, an impulse channel is provided in the rotor bottom to form a connection between the rotor interior and the nozzle-like outlet. Thus the otherwise common dividing wall in the centrifuge is rendered unnecessary, which results in a gain in capacity as regards the space that is available for sedimentation.
These and additional features of preferred embodiments of the invention will be found not only in the claims but also in the description and the drawings, and the individual features can be realized each by itself or together in the form of subcombinations in the embodiment of the invention and in other fields, and can constitute advantageous as well as independently patentable embodiments, for which protection is he
Fischer Helmut
Frehland Peter
Weber Olaf
Weindorf Martin
Cooley Charles E.
Evenson, McKeown, Edwards & Lenahan P.L.L.C.
Filterwerk Mann & Hummel GmbH
LandOfFree
Rotor for a free jet centrifuge having an internal guiding... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Rotor for a free jet centrifuge having an internal guiding..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rotor for a free jet centrifuge having an internal guiding... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2542948