Centrifugal filter for removing soot from engine oil

• US 6,517,475 B1
• Filed: 09/06/2000
• Issued: 02/11/2003
• Est. Priority Date: 09/25/1998
• Status: Expired due to Fees

• Current Assignee: Analytical Engineering, Inc.
• Original Assignee: Analytical Engineering, Inc., Baldwin Filters Incorporated (Parker-Hannifin Corporation)
• Inventors: Merritt, Steven J., Brown, Gene W., Calcaterra, Farrell F., May, David F., Beard, John H., Krempel, Louis A.
• Primary Examiner(s): Reifsnyder, David A.
• Application Number:
  US09/656,098
• Time in Patent Office: 888 Days
• Field of Search: 210/168, 210/360.1, 210/380.1, 210/DIG.17, 494/24, 494/43, 494/46, 494/49, 494/60, 494/62, 494/82, 494/84, 494/136, 184/6.24, 123/192.1, 123/196.A
• US Class Current: 494/24
• CPC Class Codes: B01D 21/262 by using a centrifuge
• CPC Class Codes: B01D 21/34 Controlling the feed distribution; Controlling the liquid level ; Control of process parameters
• CPC Class Codes: B01D 2221/08 Mobile separation devices
• CPC Class Codes: B04B 1/04 with inserted separating walls
• CPC Class Codes: B04B 1/06 of cylindrical shape
• CPC Class Codes: B04B 5/005 Centrifugal separators or filters for fluid circulation systems, e.g. for lubricant oil circulation systems
• CPC Class Codes: B04B 7/02 Casings; Lids shock absorbers, vibration dampers F16F
• CPC Class Codes: B04B 9/02 Electric motor drives dynamo-electric machines associated with centrifuges H02K7/16
• CPC Class Codes: B04B 9/06 Fluid drive
• CPC Class Codes: B04B 9/08 Arrangement or disposition of transmission gearing for solid bowl screw centrifuges B04B1/2016; Couplings; Brakes
• CPC Class Codes: B04B 9/12 Suspending rotary bowls ; Bearings; Packings for bearings
• CPC Class Codes: F01M 2001/1035 comprising centrifugal filters

Abstract

A centrifuge filter for removing soot from engine oil. The centrifuge filter includes a rotor adapted to be rotated inside a centrifuge housing by an electric motor or other means. The rotor preferably includes a reusable aluminum support casing and a disposable plastic cartridge. The plastic cartridge includes a trap with partition walls to prevent wave formation in the rotating liquid contained in the trap. The cartridge includes an annular inlet through its top end, a winding flow path through the cartridge and an outlet at the bottom. The centrifuge housing includes an isolated sealed rotor chamber. Using the venturi effect, air is evacuated from the rotor chamber to provide a partial vacuum to reduce air drag on the rotor. Resilient rubber vibration isolators are used to reduce vibrations and engine induced shock loads from reaching the rotating element. A side oil inlet is provided in the cartridge to receive unfiltered oil at a location offset from the axis of rotation. Oil is feed in through the top of the centrifuge cartridge and discharged out the bottom. The rotor is carried by bearings on a stationary central support shaft. Maintenance is performed through a removable lid on the top end of the rotor. A restriction plug is used to control flow into the rotor.

Claims

1. A centrifuge housing supporting a centrifuge rotor for rotation about a predetermined axis for removal of soot from engine oil, the centrifuge housing comprising:

an inlet port connected to the engine to receive oil;

an inlet conduit feeding oil from the inlet port into the centrifuge rotor;

a restriction plug interposed along the inlet conduit providing a restriction controlling the oil feed rate into the centrifuge rotor wherein the restriction comprises a helical passage; and

an outlet port connected to the engine adapted to collect filtered oil from the centrifuge rotor and return the oil to the engine.

2. The centrifuge housing of claim 1 wherein the size of the restriction is matched to the operative oil holding capacity of the centrifuge rotor to selectively provide a residence time for oil in the centrifuge rotor that is sufficiently long enough to facilitate removal of soot from oil.

3. The centrifuge housing of claim 2 wherein the plug is selected from a plurality of plugs, each plug providing a restriction having a different effect on the pressure and flow rate of oil into the centrifuge rotor.

4. The centrifuge housing of claim 1 wherein the plug is a threaded fastener, the housing defining a threaded opening interposed along the inlet conduit, the helical passage is defined between the respective threads of the threaded fastener and the threaded opening.

5. The centrifuge housing of claim 1 further comprising housing body having an open end and a removable lid adapted to seal the open end, the housing body including a mount adapted to be mounted to a vehicle, the centrifuge rotor being serviced through the open end via removal of the lid.

6. A centrifuge housing supporting a centrifuge rotor for rotation about a predetermined vertical axis for filtering fluid, the centrifuge rotor adapted to centrifugally separate contaminants from fluid, the centrifuge housing comprising:

a support shaft axially aligned with the predetermined vertical axis;

spaced apart upper and lower bearings supported by the support shaft, the bearings carrying the centrifuge rotor for rotation about the predetermined axis;

a spring mechanism supported by the support shaft preloading the upper bearing vertically upward counteracting the weight of the centrifuge rotor, the spring mechanism being interposed between the bearings.

7. The centrifuge housing of claim 6, wherein the spring mechanism provides an axial bias to the upper bearing that is substantially about one half of the axial thrust load of the centrifuge rotor during operation, such that the axial thrust load of the centrifuge rotor during operation is shared by both bearings.

8. The centrifuge housing of claim 6 wherein the support shaft include a larger diameter central portion and upper and lower recessed ends upon which inner races of the upper and lower bearings are supported, respectively, the spring mechanism comprising a wave spring coaxial about the upper recessed end, the spring mechanism compressed between the inner race of the upper bearings and an annular shoulder defined at the intersection of the upper recessed end and the larger diameter central portion.

9. The centrifuge housing of claim 6 further comprising an electrical motor supported by the centrifuge housing, fixed to the centrifuge rotor adapted to drive the centrifuge rotor about the predetermined axis of rotation.

10. A centrifuge housing supporting a centrifuge rotor for rotation about a predetermined axis for removal of contaminant from fluid, the centrifuge housing comprising:

support body adapted to mount to a vehicle having an internal centrifuge rotor chamber in which the centrifuge rotor is disposed for rotation;

a bearing support element carrying bearings supporting the centrifuge rotor for rotation about a predetermined axis;

a pair of spaced apart vibration isolators comprised of resilient rubber material supporting the bearing support element therebetween and interposed between the bearing support element and support body adapted to reduced vibrations from the support body to the bearing support element wherein the bearing support element and therefore the centrifuge rotor are adapted to move relative to the support body via shifts in the vibration isolators;

wherein the bearing support element comprises a support shaft, and upper and lower mounting brackets, each mounting bracket defining a cavity receiving an end of the support shaft, the bearings including an upper bearings set and a lower bearings set, each set having an inner race mounted to the drive shaft, each bracket being supported by one of the vibration isolators; and

wherein each vibration isolator is a tubular rubber ring including an outward projecting mounting flange, the tubular ring closely fitted over the mounting bracket and secured thereto by an expandable and retractable clamp ring, the mounting being clamped to the support body.

11. A centrifuge housing supporting a centrifuge rotor for rotation about a predetermined axis for removal of contaminant from fluid, the centrifuge housing comprising:

a support body adapted to mount to a vehicle having an internal centrifuge rotor chamber in which the centrifuge rotor is disposed for rotation;

a bearing support element carrying bearings supporting the centrifuge rotor for rotation about a predetermined axis;

at least one vibration isolator comprised of resilient rubber material interposed between the bearing support element and support body adapted to reduced vibrations from the support body to the bearing support element; and

further comprising an electrical motor carried by the at least one vibration isolator, the electrical motor fixed relative to the centrifuge rotor driving the centrifuge rotor about the predetermined axis, such that the electrical motor is movable relative to the support body through the vibration isolator.

12. The centrifuge housing of claim 11 further comprising a stationary annular mechanical stop provided on the support body and associated with the at least one vibration isolator adapted to engage the bearing support element to snub the radial movement of the bearing support element relative to the support body sufficiently to prevent the centrifuge rotor from contacting the support body.

13. A centrifuge housing supporting a centrifuge rotor for rotation about a predetermined axis for removal of contaminant from fluid, the centrifuge housing comprising:

a support body adapted to mount to a vehicle having an internal centrifuge rotor chamber in which the centrifuge rotor is disposed for rotation;

a bearing support element carrying bearings supporting the centrifuge rotor for rotation about a predetermined axis;

at least one vibration isolator comprised of resilient rubber material interposed between the bearing support element and support body adapted to reduced vibrations from the support body to the bearing support element;

wherein the at least one vibration isolator supports the bearing support element, wherein the bearing support element and therefore the centrifuge rotor are adapted to move relative to the support body via shifts in the at least one vibration isolator; and

further comprising a side oil outlet axially offset above the centrifuge rotor adapted to feed unfiltered fluid into the centrifuge rotor through an annular inlet in the centrifuge rotor coaxial about the predetermined axis, the side oil inlet being carried by the at least one vibration isolator wherein the side oil outlet is continuously aligned in fixed relationship with the annular inlet during all shifts in the bearing support element and centrifuge rotor relative to the support body wherein oil spillage is prevented.

14. The centrifuge housing of claim 13 wherein the support body includes an inlet port adapted to receive unfiltered oil from the engine, the inlet port connected to the side oil outlet through an inlet passage including a flexible hose to allow for relative movement between the support body and the side oil outlet.

15. A centrifuge for removal of contaminant from fluid, the centrifuge comprising:

a support housing defining a centrifuge rotor chamber in which the centrifuge rotor is adapted to rotate and including a support shaft on the predetermined axis having bearings mounted thereon carrying the centrifuge for rotation about the predetermined axis;

a centrifuge rotor being carried by the bearings for rotation about a predetermined axis; and

an electrical motor supported by the support housing comprising a stator supported by the outer support body and a rotor, the rotor comprising a drive sleeve coaxial about the support shaft holding a magnet, the drive sleeve fixed to the centrifuge rotor such that the rotor and drive sleeve rotate in unison.

16. The centrifuge of claim 15 wherein the centrifuge includes a reusable cartridge casing and a disposable centrifuge cartridge mounted therein adapted to trap contaminant, the drive sleeve being directly secured to the reusable cartridge casing.

17. The centrifuge of claim 16 wherein the drive sleeve secured to the reusable cartridge casing via interfitting threads.