US2679974A - Bearing construction for continuous centrifuge - Google Patents

Description

June 1, 1954 F. P. GOQCH BEARING CONSTRUCTION FOR CONTINUOUS CENTRIFUGE 2 Sheets-Sheet 1 Original Filed Jan. 15, 1947 INVENTOR.

F RED P. GOOCH ATTORNEY Patented June 1, 1954 UNITED STATES OFFICE BEARING CONSTRUCTION FOR CONTINUOUS CENTRIFUGE Fred P. Gooch, Media, Pa., assignor to The Sharples Corporation, a corporation of Delaware 4 Claims. 1

This application is a division of my co-pendin application Serial No. 722,124, filed January 15, 1947. The invention pertains to an improvement in centrifugal machines designed for separation of liquid from solids. More particularly, it is concerned with a machine of this type in which a mixture of liquids and solids is continuously fed to the rotor, liquid separated from the solids by rotation of the rotor during such continuous feed, and the liquid and solid fractions separately discharged from the rotor.

Features of improvement involved in the present invention include improved means for preventing leakage of liquid under treatment to bearing surfaces and preventin leakage of lubricant from bearing surfaces into the liquid under treatment.

The invention will be described in connection with a machine which, in its preferred form, includes rotating impeller means for impelling solids longitudinally of the rotor to a discharge zone for said solids, and this impeller means is driven at a speed slightly different from the speed of the rotor in order to effect the desired longitudinal movement of the solids.

Further features and advantages of the invention, and the manner in which they have been attained, will be evident from a reading of the following detailed description in the light of the attached drawing, in which,

Figure l is an elevation partly in section along the center axis of a machine in which the invention is embodied;

Figure 2 is a transverse vertical section on the line 22 of Figure 1; and

Figure 3 is a transverse vertical section on the line 33 of Figure 1.

In the drawings, the machine illustrated includes a feed conduit I!) controlled by a valve II for delivery of a mixture of liquid and solids into the hollow centrifugal rotor designated generally I3. The solids are impelled longitudinally of the rotor by a rotating scroll I4 of the nature of an impeller which causes these solids to move toward the right-hand end of the rotor as illustrated in Figure 1, at which end the rotor and impeller are driven by means of a pulley I5. The driving connection between the two includes a gear box H3 at the opposite end of the machine interconnecting the drives of the rotor and impeller and causin differential rotation of these two elements. A housing 20 surrounds the rotor, the housing, rotor and associated parts being secured to a frame 2 I.

Slurry fed to the machine through feed conduit it passes through the valve I I into conduit 22, which directs the slurry to a delivery zone I2 in the central portion of the rotor, where the slurry is discharged through a series of rotating blades 23 into the conical bowl 24 of rotor I3. Here the mixture undergoes centrifugation which deposits the heavier solids on the inner wall of bowl 24, the liquid flowing through liquid discharge ports 25 in end piece 26 of the rotor. Meanwhile, the solids are moved along the inner wall of bowl 24 by the impeller I4 and are discharged through solids-discharge ports 21 into a receiver in the form of a chute I9.

A portion of the solids may be discharged against the curviform collectin shield 28 in the upper portion of receiver I9. Solids which impinge against this surface are removed therefrom by a pair of rotating members 29, 30 passing closely adjacent to the surface of shield 28 as described and claimed in co-pendin application Serial No. 328,699, filed December 30, 1952. Although these members may be rotated independently of the rotor, being supported in such case on bearings mounted on the rotor or on any suitable supporting member, more conveniently they may be formed as shown; i. e., as opposed curved rotating members or surfaces attached to the rotor on opposite sides of discharge port 2?. These rotating members assist in conveying solids around the axis of the rotor and depositing them in receiver I9.

The rotor I 3 is driven by means of pulley I5 attached to an end piece 3! which is integral with bowl 24 of the rotor. Bearings 32 and 33 mounted at opposite ends of frame 2! permit rotation of the rotor about its axis. The end piece 26 at the large end of the rotor is attached to bowl 24 of the rotor for rotation therewith. In turn, casin 35 of gear box 56 is connected to end piece 26. Impeller I t is driven from shaft 35, which is rotated at a speed diiiering from that of the casing 34.

The impeller may be composed of sections such as 36, El, 33 and 39, each connected to the other for rotation as a unit. The curviform solids-conveying surface it may be connected to one or more of these sections for rotation at an angular speed differin from the angular speed of rotor I3. The impeller is supported by means of bearings such as Al and 42 from end pieces 26 and SI. A thrust bearing 43 may be provided to prevent longitudinal movement with respect to the rotor.

In accordance with this invention seal 44 between section 36 of the impeller and end piece 3 25 of the rotor and the seal 45 between the hollow hub section 39 and end piece 31 serve to prevent passage of materials bein subjected to centrifugation into the bearings M and 52 and to prevent contamination of these materials by lubricant from the bearings.

The bearings M and 422 may be lubricated from an external source through the channels 46 and 41. Excess lubricant passing through the bearings will be thrown into the areas 48 and 49 adjacent to the seals 44 and 45. Here the lubricant will serve to assist in sealing the bearings from material which may reach the seals from the zone of centrifugation in the rotor. When the levels of materials in the areas 48 and 69 rise towards the bearings 41 and 42, material is drawn off through the vents B and El before these levels reach the bearings. Preferably these vents discharge outside the bowl housing 29 in order to furnish an immediate warning of seal difficulty with the discharge of any materials which may build up in the chambers 48 and 19.

Although the foregoing discussion has been limited to a centrifugal machine in which the rotor is directly driven from a source of power and the impeller is driven through suitable gearing connected to the rotor, this arrangement of drive is not to be regarded as a limitation of the invention. It will be obvious that the impeller may be directly driven from the source of power, that the gear box may be driven from the impeller, and that the rotor may be revolved at a speed differing from that of the impeller through the medium of the gear box. Another suitable method of drive may be to connect a section of the gear box directly to a source of power.

The difference in speed of rotation of the impeller member i l and the rotor 33 obtained through the gear box H3 are achieved by means well known in the art, many difierent power transmission mechanisms having been disclosed for this purpose. As illustrated this includes a planetary system having a pinion 54 the rotation of which is restricted by a lever 12 and connecting link 3'3 attached to control mechanism forming no part of this invention.

The rate of feed of slurry into the rotor of the centrifugal is controlled by the valve H acting in the feed conduit 59. As illustrated gate '30 and the body H of this valve are so formed by use of curved surfaces against the flow line of the slurry that solids suspended in the liquid portion of the slurry which may impinge upon surfaces of the valve or valve body cannot remain thereon because the angles of the surfaces to the lines of flow are greater than the dynamic angle of repose of the solids.

A valve motor 9% is illustrated in Figure l as having a piston 95 which acts under fluid pressure within chamber 9! against the reaction of the spring 98, fluid pressure being admitted through line 983. Valve gate is shown attached to piston 95 by means of a'piston rod 99; thus, the position of the piston determines the aperture of the valve 'l-l. Any other means for controlling valve may be provided.

The extent of the centrifugal operation to which materials in the feed slurry are subjected is controlled by adjusting the axial position of the slurry feed means-so that the location of the zone of discharge of slurry from the feed conduit may be axially moved as described and claimed in my above-mentioned parent application. One method of doing this is by changing the position of the conduit 22 which relocates the discharge port Hlil in which the slurry passes into the discharge zone i2. Conduit 2-2 may be positioned by means of a lock screw ml or any similar positioning device so that the discharge port lilil may be located in any desired relationship with the deflectors m2. A plurality of openings in the conduit 22, each individually controlled, or relocation of the discharge lip of the port we may be used to accomplish this same purpose.

Slurry is fed to the machine through a zone I03 01" the impeller when the conduit 22 is at the right as shown in Figure 1. When the conduit 22 is the left instead of at the right as shown in Figure 1, the feed slurry passes into the rotor through a zone 104 of the impeller. This zone N34 is more remote from the solids-discharge port 2? than the zone 103 and therefore solid materials in the slurry are subjected to centrifugation for a longer period of time if the slurry is fed through the zone 1% than if the slurry is fed through the zone 33. The deflectors I62 serve to direct the slurry selectively or in any desired relative proportion into the zones 56% and Hit. Blades 23 serve to accelerate the move ment of the slurry as it passes radially through the impeller hub into the hollow body of the rotor:

The rotor cover 23 is formed in sections to permit rapid opening and inspection of the rotor and discharge conduits. This is accomplished by clamping means such as the swivelled studs Hi5 which are normally held in place by the wing nuts me. To prevent discharge of materials thrown from the rotor ports under centrifugal force, the baifle it? which may be integral with or attached to an upper section H33 oi the rotor cover overlaps lower section IE9 in the direction of rotation of the rotor i3. On the other side of the rotor a bailie Hi1 integral with or attached to the lower section 199 of the rotor housing overlaps the upper section H38 in the direction of ro tation of the rotor. The upper section of the rotor housing I68 may be supported from the lower section 289 by means of the flanges iii and H2 on the upper and lower sections respectively.

The baffles ifs! and Hi3 prevent leakage or" liquid and solid materials discharged from the bowl through ports 25 and 21 respectively to the area adjacent to the machine. The discharge of liquid is confined to the conduit H3 and the discharge of solids to the conduit lili which have appropriate connections for delivery of separated materials into receiving vessels not a part of the machine. Use of these baffles permits the employment of quick locking features such as the swivel studs described to fasten the upper sec tion of the rotor housing to the lower section. Gaskets between the sections of the housing may be dispensed with because of this baffling. These two elements, quick fasteners and the absence of a gasket, greatly facilitate removal of a section of the rotor housing whenever it is desirable or necessary to inspect the rotor and the discharge conduits for liquid and solid materials.

Various modifications are possible within the scope of the invention and I do not therefore wish to be limited except by the scope of the following claims.

-I claim:

1. A centrifugal separator having a rotor, member within said rotor mounted for rotation about the axis of rotation of said rotor, a space for centrifugal separation between said member and the inner periphery of said rotor, bearings for said member at opposite ends thereof, a seal associated with each said bearing for isolating said bearing from said space for centrifugal separation, said seal being at a greater radial distance from said axis than said bearing, a vent positioned between said seal and said bearing at a radial distance from said axis between that of said seal and that of said bearing, and means for introducing lubricant into said bearing on the opposite side thereof from said seal.

2. A centrifugal separator having a rotor, a member within said rotor mounted for rotation about the axis of rotation of said rotor, a space for centrifugal separation between said member and the inner periphery of said rotor, bearings for said member at opposite ends thereof, a seal associated with each said bearing for isolating said bearing from said space for centrifugal separation, said seal being at a greater radial distance from said axis than said bearing, and a vent positioned between said seal and said bearing at a radial distance from said axis between that of said seal and that of said bearing.

3. A centrifugal separator having a rotor, a member within said rotor mounted for relative rotation therein, a space for centrifugal separation between said member and the inner periphery of said rotor, a bearing for said member, a seal associated with said bearing for isolating said bearing from said space for centrifugal separation, said seal being at a greater radial distance from the axis of rotation of said rotor than said bearing, a vent positioned between said seal and said bearing at a radial distance from said axis between that of said seal and that of said bearing, and means for introducing lubricant into said bearing on the opposite side thereof from said seal.

4. A centrifugal separator having a rotor, a member within said rotor mounted for relative rotation therein, a space for centrifugal separation between said member and the inner periphery of said rotor, a bearing for said member, a seal associated with said bearing for isolating said bearing from said space for centrifugal separation, said seal being at a greater radial distance from the axis of rotation of said rotor than said bearing, and a vent positioned between said seal and said bearing at a radial distance from said axis between that of said seal and that of said bearing.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 499,348 Peck June 13, 1893 566,466 Nadon Aug. 25, 1896 911,652 Ericsson Feb. 9, 1909 985,588 OKelly Mar. 14, 1911 994,497 Berrigan June 6, 1911 1,027,134 Leitch May 21, 1912 1,057,443 Miller Apr. 1, 1913 1,470,947 Tyler Oct. 16, 1923 1,527,075 Peck Feb. 17, 1925 1,572,299 McEntire Feb. 9, 1926 1,655,426 Laughlin Jan. 10, 1928 1,710,315 Laughlin Apr. 23, 1929 1,828,548 Shapley Oct. 20, 1931 1,895,104 Quiron Jan. 24, 1933 1,991,490 Brewer Feb. 19, 1935 2,010,362 Herrmann et a1. Aug. 6, 1935 2,027,012 Barnes Jan. 7, 936

2,040,822 Brewer May 19, 1936 2,062,041 Robinson Nov. 24, 1936 2,271,640 Heintz Feb. 3, 1942 2,403,579 Carpenter July 6, 1946 2,408,336 Orr Sept. 24, 1946 FOREIGN PATENTS Number Country Date 225,846 Switzerland Feb. 28, 1943 297,914 Great Britain Oct. 4, 1928 428,188 Great Britain May 8, 1935 653,056 Germany Nov. 13, 937 660,902 France Feb. 26, 1929 679,427 France Apr. 12, 1930 OTHER REFERENCES B. Lenhart; pp. 84 to 86. Copy in Division 25.

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