GB1595817A - Centrifugal separator - Google Patents

Description

PATENT SPECIFICATION

( 21) Application No 21315/80 ( 22) Filed 3 Apr ( 62) Divided out of No 1 595816 ( 31) Convention Application No's.

784 124 ( 32) Filed 4 A 1 807388 17 Ju ( 33) United States of America (US) ( 44) Complete Specification published 19 Aug 1981 ( 51 INT CL 3 B 04 B 7/02 9/06 1, ( 52) ( 72) Index at acceptance B 2 P 10 C 3 B 2 3 A 3 X 6 B 9 AX 9 D 3 Inventors ROBERT E KOZULLA JAMES C KLINGENBERG ( 11) 1595817 il 1978 )ril 1977 ne 1977 in ( 54) CENTRIFUGAL SEPARATOR ( 71) We, THE GLACIER METAL COMPANY LIMITED, a British company, of 368 Ealing Road, Alperton, Wembley, Middlesex HAO 1 HD, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:-

This invention relates to centrifugal separators for separating contaminants from contaminated fluids.

Conventional fluid filters, such as oil filters, are basically mechanical strainers which include a filter element having pores which trap and segregate dirt from the fluid.

Since the flow through the filter is a function of the pore size, filter flow will decrease as the filter pack becomes clogged with dirt.

Since the filtration system must remove dirt at the same rate at which it enters the oil, a clogged conventional pack cannot process enough oil to keep the dirt level of the oil at a satisfactory level A further disadvantage of some mechanical strainer type filters is that they tend to remove oil additives.

Furthermore, the additives may be depleted to some extent by acting upon trapped dirt in the filter and are rendered ineffective for their intended purpose on a working surface in an engine.

Prior art centrifugal filters have been proposed which do not act as mechanical strainers but, rather, remove contaminants from a fluid by centrifuging For example, such a filter is shown in U S patent 3,432,091, granted to Beazley In the Beazley patent there is illustrated a hollow rotor which is rotatably mounted on a spindle.

The spindle has an axial passageway which conducts oil into the interior of the rotor.

Tangentially directed outlet ports are provided in the rotor so that the rotor is rotated upon issuance of the fluid therefrom Solids, such as dirt, are centrifuged to the sidewalls of the rotor and the dirt may be later removed by disassembling the rotor and scraping the filter cake from the sidewalls.

Such centrifugal filters have oil inlets and outlets through the base of the filter, since access to the rotor for cleaning purposes is provided by removing a shroud cover and by then removing the rotor from the spindle.

This necessitates the relatively heavy and elaborately machined base casting for the 55 centrifugal separator and the separator itself is intended to be a permanent installation which is periodically cleaned to remove the sludge buildup.

According to one aspect of the invention, 60 there is provided a centrifugal separator for separating contaminants from contaminated fluids comprising shroud means defining a first chamber, bearing means within said shroud means and having a hollow rotor 65 mounted thereon for rotation about a substantially vertical axis when the separator is in operation, said hollow rotor defining a second chamber for receiving contaminated fluids to be separated, inlet port means at 70 one end of said bearing means and shroud means, passage means through said bearing means to said second chamber, means to rotate said rotor and thereby cause contaminants in contaminated fluids within said 75 second chamber to migrate toward a sidewall of said second chamber under the influence of centrifugal force and to be separated from such contaminated fluids, said means to rotate said rotor comprising outlet port 80 means on said rotor in fluid communication with said second chamber arranged to tangentially discharge fluid from said second chamber to said first chamber, outlet port means from said first chamber, said inlet 85 port means being axially aligned with the axis of said bearing means and including attaching means capable of releasably attaching said inlet port means to a fluid supply fitting and said outlet port means 90 from said first chamber being at the other end of said shroud means.

According to another aspect of the invention, there is provided a disposable centrifugal separator for separating contamin 95 ants from contaminated fluids comprising shroud means defining a first chamber, a spindle within said shroud means and having a hollow rotor rotatably mounted thereon, the spindle extending vertically when the 100 1 595 817 separator is in operation, said hollow rotor defining a second chamber for receiving contaminated fluids to be separated, said spindle comprising an inner hollow tube and an outer hollow tube surrounding and spaced from said inner tube, an inlet port at one end of said inner tube for admitting contaminated fluids, a first outlet port adjacent the other end of said inner tube for conducting the contaminated fluids to the space between the inner and outer tubes, a second outlet port adjacent one end of said outer tube at an end of said tube remote from said other end of said inner tube and communicating with said second chamber, screen means surrounding said outer tube and with said outer tube defining a third chamber within said second chamber, baffle means separating said second outlet port from direct communication with said tnirci member, means to rotate said rotor and thereby cause contaminants in contaminated fluids within said second chamber to migrate toward a sidewall of said second chamber under the influence of centrifugal force and to be separated from such contaminated fluids, said means to rotate said rotor comprising tangentially mounted outlet port means on said rotor in fluid communication between said third and first chambers to cause said rotor to rotate upon discharge of fluid from said third chamber to said first chamber and a third outlet port leading from said first chamber at an end of said shroud opposite said inlet port.

This invention, in its preferred forms, provides a centrifugal separator which is inexpensive, which may be disposed of after use rather than disassembled for cleaning, and which includes a baffle between the rotor and the outlet of the separator to break up fluid buildup on the sidewall of the separator, which would tend to interfere with rotation of the rotor An inlet is provided at one end of the separator and an axially aligned outlet is provided at the other end of the separator so that the outward appearance of the device is very similar to a conventional automotive spin-on engine block canister filter It is intended that the separator be replaced every 50,000 miles; therefore, its construction may not be as rugged or expensive as conventional centrifugal separators.

A preferred form of the invention will now be described in more detail A closed shroud means defines a first chamber and a vertically extending spindle is mounted within the shroud and has a permanently sealed, hollow rotor rotatably mounted thereon The rotor defines a second chamber for receiving contaminated fluids to be separated and the spindle comprises an inner hollow tube and an outer hollow tube surrounding and spaced from the inner tube An inlet port is provided at one end of the inner tube for admitting contaminated fluids and an outlet port is provided adjacent the other end of the inner tube for conducting contaminated fluids to the space 70 between the inner and outer tubes There is further provided an outlet port adjacent one end of the outer tube at an end of the tube remote from the other end of the inner tube and communicating with the second 75 chamber A screen surrounds the outer tube, and with the outer tube defines a third chamber A baffle separates the outlet port in the outer tube from direct communication with the third chamber The rotor is rotated 80 to cause contaminants in contaminated fluids in the second chamber to migrate toward a sidewall of the second chamber under the influence of centrifugal force and be separated from the contaminated fluids 85 The rotor is rotated by tangentially mounted outlet ports on the rotor in fluid communication with the third chamber to cuase the rotor to rotate upon discharge of fluid from the second chamber to the first chamber 90 There is provided a bleeder valve in the first chamber to allow adequate drainage.

The drainage must pass through an outlet fitting which is smaller in flow area than the drain of many prior art arrangements The 95 bleeder valve provides an atmospheric reference between the inside and the outside of the first chamber, thereby venting the section created during drainage.

There is further provided a baffle means 100 between the rotor and the outlet port The baffle means preferably comprises a flat screen which extends from the rotor spindle to the sidewalls of the first chamber The baffle prevents the fluid from moving up the 105 sidewall of the first chamber to interfere with the rotating rotor Furthermore, the baffle means tends to reduce vibrations of the spindle, since it acts as a stiffening member 110 The drawing illustrates a preferred centrifugal separator or filter according to this invention, partly in section, and an engine block mounting fitting for receiving the separator 115 Referring now to the drawing, there is illustrated a centrifugal separator 10 having a sealed shroud 11 which defines a first chamber 12 The shroud 11 comprises a drawn sheet metal can having a lid 13 joined 120 to the can be a conventional can-type rolled seam 14 to form a permanently closed housing with ends and intermediate sides The lid 13 includes a relatively thick support disc 15 and a relatively thin gauge ring 16 welded to 125 the support disc 15 The ring 16 is shaped to retain a sealing gasket 17 in a rolled channel 18 Inlet port means comprise an axially aligned inlet attachment fitting 19 which extends through and is permanently associ 130 1 595 817 ated with the support disc 15 Outlet port means comprise an axially aligned outlet fitting 20 which is permanently affixed to and extends through the other end of the shroud 11 The shroud 11 also has attached to it a bleed valve 48 having a light ball 50 which remains off its seat by gravity during the filter operation If for some reason the outlet flow is throttled, the first chamber will fill with oil, thereby forcing the ball to its seat and preventing oil from leaking to the atmosphere It should be appreciated that the style and configuration of the inlet and outlet fittings 19 and 20 are subject to particular mounting requirements for the separator.

A hollow rotor 21 is rotatably mounted on bearing means provided by a spindle assembly 22 The rotor 21 defines a second chamber 23 and comprises a can 24 which is closed by a base 25 joined to the can 24 by a rolled seam 26 Tangential and oppositely directed outlet ports 27 and 28 are formed in the base 25 in depressions 29.

The spindle assembly 22 comprises an inner tube or spindle 30 threaded into the inlet fitting 19 and a concentrically arranged outer tube 31 mounted for rotation relative to the inner tube 30 by bearings 32 The rotor assembly 21 is fixed to the rotatable outer tube by snap rings 33 The rotor assembly 21 and the spindle assembly 22 are supported by the inlet fitting 19 which has a neck 34 extending into the outer tube 31 and by a heavy spring 35 which has a thrust pad 36 projecting into the inner tube 30.

The spring 35 permits fluid access from the first chamber 12 to the outlet fitting 20.

Oil enters the inlet fitting 19 from a fitting 37 on an engine block 38 and flows to an outlet port 39 in the tube 30 The outlet port 39 is normally closed by a check valve 40, which comprises a spool 41 slidable in the inner tube 30 to a normally closed position across the port 39 and held in that position by a spring 42 At a predetermined pressure within the tube 30, the spool slides against the bias of the spring 42 to open the port 39.

Thus, during idling or start-up conditions, when the oil pressure is not high, the separator 10 will not be operable Oil issuing from the outlet port 39 flows through a space between the inner and outer tubes and through outlet ports 43 in the outer tube.

There is provided a baffle 44 around the outlet ports 43 to direct oil into the second chamber 23 The oil egresses from the second chamber 23 to the first chamber 12 through the reaction nozzles 27 and 28 In order to reach the reaction nozzles 27 and 28, the oil must pass through a cylindrical screen 45 which surrounds the outer tube and which, with the baffle 44 and an annular plate 46, defines a third chamber 47 Desirably, the screen 45 has a mesh which is finer than the nozzle openings 27 and 28 so that these openings will not be plugged by any large particles which may tend to migrate to the third chamber 47 Oil is expelled from the second chamber through the tangen 70 tially mounted outlet ports 27 and 28 and, since those ports are oppositely directed, they cause the rotor assembly 21 to rotate according to the principle of Hero's engine.

As the rotor assembly 21 rotates, sus 75 pended solids migrate to and are retained at the sidewall of the rotor with a force which is dependent on the running oil pressure of the engine In time, the dirt particles and sludge form a rubbery mass at the rotor 80 sidewall After a predetermined number of miles, this mass will accumulate until the entire separator must be replaced.

A baffle screen 55 is provided to prevent the buildup of fluid along the inner sidewall 85 of the first chamber 12 But for the presence of the screen 55, the fluid issuing from the tangential outlet ports 27 and 28 would tend to creep upwardly on the sidewalls of the first chamber 12, as is indicated by the dot 90 ted line 56 While the theory of operation of the screen 55 is not completely understood, its presence tends to flatten out the curvature of the surface of the liquid to a level indicated by the line 57 95 The baffle 55 is a disk-shaped piece of screening with a central aperture which also tends to stabilize the spindle at high speeds, since it serves as a structural support Of course, it should be appreciated that other 100 baffles may be employed, such as spokes, which radiate from the spindle to the sidewall of the first chamber, or other means that would disrupt the smooth swirling of the oil as it emerges from the tangential out 105 let ports 27 and 28.

Finally, attention is drawn to our related copending Patent Application No.

13001/78 (Serial No 1 595 816).

Claims (11)

WHAT WE CLAIM IS: 110

1 A centrifugal separator for separating contaminants from contaminated fluids comprising shroud means defining a first chamber, bearing means within said shroud means and having a hollow rotor mounted 115 thereon for rotation about a substantially vertical axis when the separator is in operation, said hollow rotor defining a second chamber for receiving contaminated fluids to be separated, inlet port means at one end 120 of said bearing means and shroud means, passage means through said bearing means to said second chamber, means to rotate said rotor and thereby cause contaminants in contaminated fluids within said second 125 chamber to migrate toward a sidewall of said second chamber under the influence of centrifugal force and to be separated from such contaminated fluids, said means to rotate said rotor comprising outlet port 130 1 595 817 means on said rotor in fluid communication with said second chamber arranged to tangentially discharge fluid from said second chamber to said first chamber, outlet port means from said first chamber, said inlet port means being axially aligned with the axis of said bearing means and including attaching means capable of releasably attaching said inlet port means to a fluid supply fitting and said outlet port means from said first chamber being at the other end of said shroud means.

2 A centrifugal separator according to Claim 1, wherein the shroud means has ends and intermediate sides which substantially fully define the first chamber and which form a permanently closed housing and wherein the attaching means are permanently fixed to the shroud means and are capable of providing substantially the sole support of said separator.

3 A centrifugal separator according to claim 1 or 2, wherein said outlet port means is axially aligned with said inlet port means.

4 A centrifugal separator according to claim 1, 2 or 3, wherein there is provided a sealing ring on said shroud surrounding said inlet port means.

A centrifugal separator according to any preceding claim, wherein the bearing means comprise a spindle extending through the rotor.

6 A disposable centrifugal separator for separating contaminants from contaminated fluids comprising shroud means defining a first chamber, a spindle within said shroud means and having a hollow rotor rotatably mounted thereon, the spindle extending vertically when the separator is in operation, said hollow rotor defining a second chamber for receiving contaminated fluids to be separated, said spindle comprising an inner hollow tube and an outer hollow tube surrounding and spaced from said inner tube, an inlet port at one end of said inner tube for admitting contaminated fluids, a first outlet port adjacent the other end of said inner tube for conducting the contaminated fluids to the space between the inner and outer tubes, a second outlet port adjacent one end of said outer tube at an end of said tube remote from said other end of said inner tube and communicating with said second chamber, screen means surrounding said outer tube and with said outer tube defining a third 55 chamber within said second chamber, baffle means separating said second outlet por from direct communication with said third chamber means to rotate said rotor and thereby cause contaminants in contami 60 nated fluids within said second chamber to migrate toward a sidewall of said second chamber under the influence of centrifugal force and to be separated from such contaminated fluids, said means to rotate said 65 rotor comprising tangentially mounted outlet port means on said rotor in fluid communication between said third and first chambers to cause said rotor to rotate upon discharge of fluid from said third chamber to 70 said first chamber, and a third outlet port leading from said first chamber at an end of said shroud opposite said inlet port.

7 A centrifugal separator as set forth in claim 6 wherein said first and second cham 75 bers are permanently sealed.

8 A centrifugal separator according to claim 6 or 7 wherein a pressure-responsive valve is provided between the inlet and outlet ports of said inner tube and is openable 80 upon the attainment of a predetermined pressure.

9 A centrifugal separator according to claim 8, wherein said pressure responsive valve comprises a valve spool slidable within 85 said inner tube and spring biased to a position blocking the outlet port of said inner tube in the absence of said predetermined pressure.

A centrifugal separator according to 90 any one of claims 6 to 9, wherein said inlet port at said one end of said inner tube is axially aligned with the third outlet port.

11 A centrifugal separator according to any preceding claim, which is in the form of 95 an oil cleaner for attachment to a crank case.

For the Applicants, D YOUNG & CO, Chartered Patent Agents, Agents for the Applicants, Staple Inn, London, WC 1 V 7RD.

Printed for Her Majesty's Stationery Office by The Tweeddale Press Ltd, Berwick-upon-Tweed, 1981 Published at the Patent Office, 25 Southampton Buildings, London, WC 2 A l AY, from which copies may be obtained.