US3684160A

US3684160A - Centrifuge having a rotation-sensitive pumping device

Info

Publication number: US3684160A
Application number: US61573A
Authority: US
Inventors: Hans Peter Olof Unger; Johan Eric Hayden Westberg
Original assignee: AGA AB
Current assignee: AGA AB
Priority date: 1969-08-11
Filing date: 1970-08-06
Publication date: 1972-08-15
Anticipated expiration: 1989-08-15
Also published as: DE2039899A1; FR2056608A5; SE334331B

Abstract

A rotation-sensitive pumping device for pumping liquid from one part of a centrifuge to another during rotation thereof comprises a diaphragm mounted on the centrifuge rotor and moveable from one position to another as a function of rotor speed to pump the liquid. The diaphragm is disposed at an angle between two rotating chambers of the centrifuge and, at a given angular velocity of the rotor, the diaphragm is moved by centrifugal force from one position to the other to pump the liquid from one chamber to the other. The diaphragm may include two flexible diaphragms separated by a cavity filled with a fluid. A partition wall may be located in the space between the diaphragms forming cavities between the partition wall and each diaphragm. An aperture is provided in the partition wall for the passage of fluid between the two cavities on motion of the diaphragms.

Description

United States Patent 1 Unger et a1.

[451 Aug. 15, 1972 CENTRIFUGE HAVING A ROTATION- SENSITIVE PUMPING DEVICE Inventors: Hans'Peter Olof Unger, Stockholm;

Johan Eric Hayden Westberg, Lidingo, both of Sweden Assignee: AGA Aktiebolag, Lidingo, Sweden Filed: Aug. 6, 1970 Appl. No.: 61,573

Foreign Application Priority Data Aug. 11, 1969 Sweden ..l l 119/69 US. Cl. ..233/20 R Int. Cl. ..B04b 11/00 Field of Search ..233/26, 27, 28, 29, 35, 39,

References Cited UNITED STATES PATENTS 12/1953 Abbott ..233/27 Peck ..233/9 MacRlind .L.233/20 Primary Examiner-.lordan Franklin Assistant Examiner-George H. Krizmanich Attorney-Larson, Taylor and Hinds 5 7 1 ABSTRACT A rotation-sensitive pumping device for pumping liquid from one part of a centrifuge to another during I rotation thereof comprises a diaphragm mounted on the centrifuge rotor and moveable from one position to another as a function of rotor speed to pump the liquid. The diaphragm is disposed at an angle between two rotating chambers of the centrifuge and, at a given angular velocity of the rotor, the diaphragm is moved by centrifugal force from one position to the other to pump the liquid from one chamber to the other. The diaphragm may include two flexible diaphragms separated'by a cavity filled with a fluid. A partition wall may be located in the space between the diaphragms forming cavities between the partition wall and each diaphragm. An aperture is provided in the partition wall for the passage of fluid between the two cavities on motion of the diaphragms.

, 6 Claims, 2 Drawing Figures PATENTED M18 15 I972 INVENTORS HANS P. O. UNGER JOHAN E. H. WESTBERG fi Z50c03 7/eg BY AT TOR NEYS CENTRIFUGE HAVING A ROTATION-SENSITIVE PUMPING DEVICE BACKGROUND OF THE INVENTION The invention relates to a rotation-sensitive pumping device for centrifuges. More particularly, the invention relates to such devices for the transfer of liquid from one portion of a centrifuge to another portion during rotation thereof.

In centrifuges where a pumping effect is' desired for the transfer of a liquid from one part of the centrifuge to another, a simplification of the working procedure can be achieved by making the pumping effect dependent on the number of revolutions. Governor devices depending on the speed of revolutions and utilizing weights are well-known for this purpose. It is an object of the present invention to provide a simplified speeddependent pumping device of this type.

BRIEF SUMMARY OF THE PRESENT INVENTION The foregoing and other objects which will be apparent to those having ordinary skill in the art are achieved according to the present invention by providing a rotation-sensitive pumping device for pumping a liquid from one part of the centrifuge to another during rotation thereof comprising a diaphragm, means for mounting the diaphragm on a centrifuge rotor to revolve therewith, said diaphragm being responsive 'to the angular velocity of said rotor to move between first and second positions as a function of angular velocity of said rotor, said diaphragm being positioned to pump said liquid between said parts of said centrifuge upon motion of said diaphragm between said first and second positions.

DETAILED DESCRIPTION There follows a detailed description of a preferred embodiment of the invention, together with accompanying drawings. However, it is to be understood that the detailed description and accompanying drawings are provided solely for the purpose of illustrating a preferred embodiment and that the invention is capable of numerous modifications and variations apparent to those skilled in the art without departing from the spirit and scope of the invention.

FIG. 1 is a schematic side elevation, in section, of a pumping device according to the present invention.

FIG. 2 is a cross-sectional view of a weighted diaphragm useful in the device of FIG. 1.

A centrifuge rotor 1 or a part there of comprises a plate 2 of a non-flexible material which is penetrated by an opening 3. On the upper side of the plate is situated a rubber diaphragm 4 and on the lower side a similar rubber diaphragm 5. Both diaphragms are annular and matched to the plate and fixed at the inner and outer edges thereof as can be seen in the figure. Between the diaphragms a cavity 6 is formed in which is a liquid. A cover 7 of heavy material is fixed to diaphragm so as to increase the weight of the diaphragm and thus increase the sensitivity of the diaphragm to the speed of rotation. The same result can be achieved by incorporating a heavy material 12 (FIG. 2) blended with the rubber itself in the diaphragm 5. Not only the diaphragm 5 but also the diaphragm 4 may be loaded so as to increase its weight. The loadin is such that the diaphragms are given a substantial y higher specific gravity than the liquid which is to be transferred.

Above the diaphragm 4 is a chamber 8 and below the diaphragm 5 is a similar chamber 9. Both

chambers

8 and 9 are interconnected by a tube 10 and both are mounted for rotation on rotor 1.

The volume of the displacement fluid in the space 6 is matched to the amount of liquid which is intended for transfer from one of the

chambers

8, 9 to the other. The diaphragms 4 and 5 may have annular shape, and being clamped along the edges as shown in the figure, the diaphragms will then, if no rotation takes place, be curved downwards as shown.

In the arrangement described, diaphragms 4 and 5 will assume the position as shown in the figure at rest and at low speed. If the speed exceeds a certain value, the centrifugal force on the diaphragm 5 ultimately becomes sufficient that it is pressed upwards and outwards which'causes the displacement fluid to be moved into the interspace between the plate 2 and the diaphragm 4. A corresponding amount of fluid is simultaneously pumped from chamber 8 to chamber 9 through conduit 10.

Through appropriate selection of the bias and weight of the diaphragm in relation to the specific gravity of the pumped liquid the value of speed may be selected at whith the transition from one position to the other occurs.

The device is particularly useful in a centrifuge of the type described in U.S. application Ser. No. 6l, 5 83 filed Aug. 6, 1970 which is herein incorporated by reference.

What is claimed is: y

1. In a centrifuge having-a rotor, first and. second chambers for liquid to be centrifuged connected to said rotor for rotation therewith, a conduit for said liquid interconnecting said chambers, and a rotation sensitive pumping device for pumping a liquid from one chamber to the other during the rotation thereof, wherein said pumping device comprises diaphragm means interposed between said chambers for rotation with said rotor, said diaphragm means including a diaphragm moveable between first and second positions as a function of angular velocity of said rotor to pump liquid from one of said chambers to the other.

2. An improved centrifuge according to claim 1 wherein said diaphragm is conical in cross section.

3. An improved centrifuge according to claim 2 wherein said diaphragm means comprises a second diaphragm spaced from the said diaphragm defining a cavity between said diaphragms, said cavity being filled

Claims

1. In a centrifuge having a rotor, first and second chambers for liquid to be centrifuged connected to said rotor for rotation therewith, a conduit for said liquid interconnecting said chambers, and a rotation sensitive pumping device for pumping a liquid from one chamber to the other during the rotation thereof, wherein said pumping device comprises diaphragm means interposed between said chambers for rotation with said rotor, said diaphragm means including a diaphragm moveable between first and second positions as a function of angular velocity of said rotor to pump liquid from one of said chambers to the other.

3. An improved centrifuge according to claim 2 wherein said diaphragm means comprises a second diaphragm spaced from the said diaphragm defining a cavity between said diaphragms, said cavity being filled with a fluid.

4. An improved centrifuge according to claim 3 wherein said cavity is divided by a rigid partition wall defining a cavity between each of said diaphragms and said partition wall, said partition wall including an aperture interconnecting the cavities.

5. An improved centrifuge according to claim 2 wherein said diaphragm comprises a flexible diaphragm material and a weight increasing material secured thereto.

6. An improved centrifuge according to claim 2 wherein said diaphragm comprises a flexible diaphragm material incorporating a weight increasing material.