Abstract:
Apparatus and process for improved contaminant removal from engine lubricating oil are provided. The invention is adapted for use with an existing engine oil lubrication system and continuously processes a side stream that after processing is returned to the engine oil. During processing, the oil is first filtered and then is deposited to form a thin film upon upper internal surface regions of a heated, generally conically configured platen whose average transverse internal diameter generally decreases with increasing downward distance from said upper internal surface regions. The platen internal surface regions preferably have a plurality of slope changes. Oil so deposited on the platen internal surface regions forms a thin film that flows downwards and preferably experiences a variable flow rate and variable film thickness. Volatiles produced from the thin film are separated and vented preferably from a chamber over the platen, while oil consolidated from the thin film at the platen bottom is collected and recycled.

Description:
FIELD OF THE INVENTION  
       [0001]     This invention relates to lubricating oil reconditioning devices and processes for utilization with an operating internal combustion engine.  
       BACKGROUND OF THE INVENTION  
       [0002]     Filtering of circulating lubricating oil does not remove miscible liquid contaminants from the oil. These contaminants are mainly water and low boiling organic chemicals whose presence in lubricating oil cause engine corrosion and wear.  
         [0003]     Lubricating oil reconditioning systems that are associated with an internal combustion engine and that function to remove such liquid contaminants from lubricating oil being circulated in the operating engine are known; see, for example, DePaul U.S. Pat. Nos. 5,707,515 and 6,083,406. Although functional and effective, improvements in such systems would be desirable particularly to improve operational efficiency and reliability.  
         [0004]     So far as is now known, no one has previously achieved a lubricating oil reconditioning system wherein oil from an operating internal combustion engine is first filtered and then passed as a thin film using gravity as a primary flow-inducing force over internal surface regions of a generally conically tapered heated platen, particularly a platen where a thin film is moved over platen internal surfaces that are arranged so that lower internal surface portions thereof generally have a smaller diameter than upper internal surface portions thereof. Preferably, the internal surface regions of the platen define a plurality of localized slope changes whereby the descending thin film of oil on the internal surface regions experiences a variable flow rate and a variable film thickness before reaching a bottom region where the resulting oil is collected and recycled for engine lubrication.  
       SUMMARY OF THE INVENTION  
       [0005]     This invention relates to new and very useful improved apparatus and processes for continuously accomplishing removal of low boiling liquids, such as water, from the lubricating oil of an operating internal combustion engine.  
         [0006]     In accord with the invention, a side stream of circulating engine lubricating oil is processed continuously as the engine operates. The side stream usually and preferably comprises a minor fraction of the total quantity of engine lubricating oil that is being conventionally pumped through an engine, contacted with bearing surfaces thereof, and moved to a filtering zone.  
         [0007]     In accordance with the present invention, either before or preferably after the filtering zone, a side stream of the engine lubricating oil is continuously removed, preferably separately filtered, and then conveyed to a volatile contaminant removal processing zone. In this processing zone, the side stream oil is continuously deposited upon upper internal surface regions of a preferably generally conically tapered, heated platen. A thin film of the deposited oil is formed on internal surface portions of the platen, and the thin film of oil flows downwardly thereover using gravity as a primary moving force.  
         [0008]     The internal surface region of the platen is oriented so that lower internal surface portions thereof generally have a smaller perimeter or diameter relative to upper internal surface portions thereof. Preferably, the platen internal surface regions define a plurality of localized slope changes whereby the descending thin film on the internal surface regions experiences at local regions of the platen a variable flow rate and a variable film thickness. Oil reaching a platen bottom region is collected and recycled for engine lubrication usage.  
         [0009]     Volatile components are evolved from the oil in the precessing zone, particularly as the oil descends as a thin film over platen interior surface regions, is separated and preferably vented. Preferably, the processing zone involves a chamber that is provided over the platen and that is over the oil input locations for the platen. The chamber can be defined by a housing. Vapors collecting in the processing zone are conveniently released to the atmosphere through a relief valve, which is preferably a check valve.  
         [0010]     To accomplish a generally uniform distribution of the filtered oil over the internal surface portions of the platen, various arrangements can be utilized. It is presently preferred to accomplish a substantially uniform distribution of entering oil over upper internal surface portions of the platen. This distribution is accomplished preferably by charging the filtered oil to a metering jet. Oil passing through the metering jet enters into a distributing chamber. The distributing chamber is preferably located centrally over upper portions of the platen.  
         [0011]     From bottom portions of the distributing chamber, oil flows through a plurality of circumferentially spaced, radially extending tube members to a circumferentially extending, rim-like distributing tube that is horizontally oriented, located over upper portions of the platen, and is in preferably equally outwardly spaced relationship relative to the distributing chamber. The distributing tube is provided with a plurality of holes in its gravitationally lower portions. Thus, oil reaching the distributing tube flows downwardly out of the holes therein and descends to upper internal surface portions of the platen where the oil forms a thin film that downwardly flows thereover.  
         [0012]     Conveniently and preferably, the platen is electrically heated to a desired elevated temperature by a resistance heating element or the like that is located on and about outside wall portions of the platen yet is inside of a housing, thereby isolating the heating element from direct contact with oil.  
         [0013]     The inventive apparatus and method provide various advantages over the prior art. For example, the present conically configured platen in the inventive combination appears to provide improved thin film flow characteristics over its interior surface regions compared to the dome configured platen described in DePaul &#39;406 (cited above), for example.  
         [0014]     Other and further objects, aim, purposes, features, advantages, component substitutes, operating conditions, embodiments and the like will be apparent to those skilled in the art from the present description taken with the associated drawings and the appended claims. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]     In the drawings:  
         [0016]      FIG. 1  is a fragmentary diagrammatic view illustrating one embodiment of an oil reconditioning system of the present invention in functional association with the lubrication system of a fuel combusting engine;  
         [0017]      FIG. 2  is a partial diagrammatic vertical sectional view through a presently preferred embodiment of an oil reconditioning system of the present invention;  
         [0018]      FIG. 3  is top plan view of the platen employed in the  FIG. 1  system;  
         [0019]      FIG. 4  is an enlarged, longitudinal sectional view through a bracket employed in the  FIG. 1  system to support the distribution pipe thereof;  
         [0020]      FIG. 5  is a fragmentary plan view of the electric heating element employed in the  FIG. 1  system;  
         [0021]      FIG. 6  is a fragmentary bottom plan view of the oil distribution system employed in the  FIG. 1  system;  
         [0022]      FIG. 7  is a fragmentary sectional view taken through the distribution pipe employed in the  FIG. 1  system;  
         [0023]      FIG. 8  is a side elevational view of an alternative embodiment of a platen adapted for use in the  FIG. 1  system;  
         [0024]      FIG. 9  is a fragmentary longitudinal sectional view through the platen of  FIG. 8 ;  
         [0025]      FIG. 10  is a side elevational view of a further alternative embodiment of a platen adapted for use in the  FIG. 1  system;  
         [0026]      FIG. 11  is a fragmentary longitudinal sectional view through the platen of  FIG. 10 ;  
         [0027]      FIG. 12  is a fragmentary side elevational view of another pattern for a platen adapted for use in the  FIG. 1  system;  
         [0028]      FIG. 13  is a view similar to  FIG. 12 , but showing another platen sidewall pattern;  
         [0029]      FIG. 14  is a view similar to  FIG. 12 , but showing another platen sidewall pattern;  
         [0030]      FIG. 15  is a view similar to  FIG. 12 , but showing another platen sidewall pattern;  
         [0031]      FIG. 16  is a fragmentary view similar to  FIG. 8 , but showing another platen embodiment; and  
         [0032]      FIG. 17  is a fragmentary view similar to  FIG. 8 , but showing another platen embodiment. 
     
    
     DETAILED DESCRIPTION  
       [0033]     Referring to  FIG. 1 , there is seen one embodiment 20 of an engine lubricating oil reconditioning system of the present invention. In system  20 , lubricating oil that has drained and collected in a conventional engine oil pan  21  is withdrawn by a conventional engine lubricating oil pump  22  through an interconnecting conduit  23  that incorporates a conventional lubricating oil screen structure  24  located in oil pan  21 . From pump  22 , the oil is passed to a main lubricating oil stream successively through respective conduits  26  and  27  into a conventional replaceable oil filter  28  or the like. The oil filter, if desired, may have a multi-stage core or may have multiple stages, such as three or five stages, for example, that may be encased in a housing.  
         [0034]     In filter  28 , oil under partial pump  22  pressure from conduit  27  is conventionally filtered to remove filterable contaminants, such as particulates including sludge; and the filtered oil passes into a conduit system  33  through which it is conveyed to engine bearings  34  for conventional lubrication purposes. From the bearings  34 , the oil drains down (not detailed in  FIG. 1 ) and is again collected in the oil pan  21  for recycling through pump  22 .  
         [0035]     Conduits  26  and  27  are connected together through a by-pass valve or proportional flow divider  29  into two streams, a main oil stream in conduit  27  comprising more than 50 volume percent of the oil that enters and flows through conduit  26  and a side oil stream in conduit  31  comprising the remaining volume percent of the oil. The side stream that enters and flows through conduit  31  feeds into an embodiment of the oil reconditioning apparatus of this invention, such embodiment being generally designated by the numeral  32 .  
         [0036]     From conduit  31 , the side oil stream under partial pressure generated by pump  22  enters into oil reconditioning apparatus  32  and is processed as described herein first to separate filterable contaminants and then to separate low boiling contaminants from the oil. The resulting processed and reconditioned oil exits from apparatus  32  through interconnecting conduit  36  and preferably passes (not detailed in  FIG. 1 ) into oil pan  21  or the like for recycling and reuse in engine lubrication. The volatiles separated from the oil in apparatus  32  are discharged from apparatus  32  either into the atmosphere through vent  63  (which preferably is equipped with a check valve (not shown)), or into a conduit  37  for conveyance to the engine intake manifold (not detailed), or otherwise, as may be desired.  
         [0037]     The system  32  is well suited for installation in combination with a previously manufactured vehicular engine or the like using a kit or the equivalent.  
         [0038]     Such a kit can comprise, for example, the proportional flow divider  29 , components of the oil reconditioning apparatus  32  and the interconnecting conduit components, such as conduit  31 . Observe that, in the system  20 , one could consider that there are essentially two lubricating oil reconditioning systems, one system involving the main oil stream that is charged to conduit  27  and in which the filter  28  is used for oil processing, and the second system  32  involving the side oil stream that is charged to conduit  31  in which the apparatus  32  is used for oil processing. It is a feature of the system  20  that it can be functionally associated with a vehicular engine without redesigning the originally installed lubricating oil system. Thus, usually even the originally installed lubricating oil pump (which is commonly located in the oil pan) can be used in operating the system  20 .  
         [0039]     Referring to  FIGS. 2-7 , for example, the structure and operation of the lubricating oil reconditioning apparatus  38  is seen wherein low boiling volatiles are separated in the oil reconditioning apparatus  32  of this invention. Preliminarily, the oil side stream is filtered to remove particulates including sludge through a filter  35 . In the apparatus  32 , through a conduit  39  that extends in gas-tight relationship through a side portion of a top cap plate  41 , a stream of filtered oil from filter  35  is delivered to and enters a central chamber  42  through a metering orifice or metering jet  43 . The chamber  42  is defined by a generally cup-configured body  44  that has cylindrical side walls, an integral flat bottom and outwardly extending top mounting flange portions. Outer edge portions of the mounting flange portions that are adapted to lie flat against bottom edge portions of downwardly extending ribs integrally formed on under surface portions of the top plate  41 . The mounting flange portions of body  44  are mounted against the bottom edge portions by machine screws  40  or the like that extend upwardly normally through the mounting flange portions into threaded engagement with the rib portions, although alternative configurations and mounting arrangements can be used, if desired.  
         [0040]     Radially extending outwardly from a functionally interconnected relationship with bottom portions of the cylindrical side walls of body  44  are a plurality of straight, radially extending, spoke-like conduits  46  (preferably four, equally circumferentially spaced), as shown. Each conduit  46  terminally functionally interconnects with local circumferential surface portions of a circular tubular pipe  47  that is horizontally oriented, that is located above top edge portions of the platen  51 , and that is preferably substantially coaxial with the body  44 . Thus, portions of the circular pipe  47  are approximately equally radially spaced from adjacent portions of the body  44 .  
         [0041]     A plurality of brackets  49  (preferably four, see, for example,  FIG. 4 ) are provided. Each bracket  49  has a hook-configured foot portion for extending under and supporting a local portion of the pipe  47  and also a flat head flange portion for mounting to downwardly projecting rib portions or the like of the top plate  41 . Thus, each flat head flange portion is adapted to lie flat against adjacent under surface portions of the top plate  41  and is mounted against adjacent top plate  41  under surface portions by machine screws that extend normally through the head flange portions into threaded engagement with the top plate  41 . Preferably, the individual brackets  49  are circumferentially generally equally spaced from one another and function to support the pipe  47  in the desired centered, flat, central orientation and spacing relationship relative to the body  44 , as shown. Alternative configurations and mounting arrangements can be used, if desired.  
         [0042]     Lower portions of the pipe  47  are provided with a plurality of small holes  48  (see, for example,  FIGS. 6 and 7 ). Thus, oil in chamber  42  moves into and passes through the conduits  46 , enters the pipe  47 , and is substantially uniformly distributed therein. Oil in pipe  47  passes downwardly through the holes  48  and is deposited on upper interior surface portions of the generally conically configured platen  51  forming a thin film on interior surface portions thereof.  
         [0043]     The housing  52  and the cap plate  41  are conveniently formed of cast, machined metal, and the platen  51  is conveniently formed of stamped, welded sheet metal, preferably stainless steel.  
         [0044]     Internal surface portions of the platen  51  preferably have a plurality of slope changes. In the preferred form of platen  51  shown in  FIG. 2 , the platen  51  is provided at regular longitudinal intervals along its length with inturned ledge regions that give the platen  51  sidewalls, when viewed in longitudinal section, a stair-step type of configuration. Alternative configurations and arrangements can be utilized, if desired. The purpose of the localized variations in platen  51  sidewall slope to achieve slope changes in interior surface portions of the platen  51 , as those skilled in the art will appreciate, thereby to enhance changes in film thickness and flow rate as the oil film descends. As the oil film descends, its exposed surface area declines, which may aid in removing volatiles from the oil being processed. Also, as the oil descends, it is concentrated which is desirable for oil collection purposes at the bottom portions of the platen  51 .  
         [0045]     Upper edge portions of platen  51  are provided with an outturned flange  57 . The platen  51  is contained in a housing  52  that has generally cylindrical side walls  53  that are joined unitarily at bottom edge portions to a dome configured bottom plate  54 . An outturned rim flange  41 a on perimeter portions of the top plate  41  mounts by machine screws or the like over, and sealingly closes, with the aid of a seal (not shown), the upper edge portions of the cylindrical side walls  53 , thereby completing an enclosure within the housing  52 . Circumferentially extending about inside wall portions of the side walls  53  in downwardly spaced, adjacent relationship to the upper edge portions of the side walls  53  is a ledge projection  56 . Against the flattened upper face of the ledge projection  56  rests the outturned flange  57  of the platen  51 . The flange  57  is mounted to the ledge projection  56  by a plurality of circumferentially spaced machine screws  45  or the like. Thus, the platen  51  divides the enclosure defined by the housing  52  into an upper chamber  58  and a lower chamber  59 .  
         [0046]     Oil that drops from the holes  48  in the circular pipe  47  upon the upper interior surface portions of the platen  51  forms a thin film moves downwards by gravity over the heated surface portions of the platen  51 . Since the internal surface regions define a plurality of slope changes, the oil flowing thereover experiences a variable flow rate and a variable film thickness as it progresses to the bottom regions of the platen  51 . Such variations are preferred and are believed to be desirable for purposes of enhancing the separating and removing of volatile materials from the oil being so treated. Evidently, more volatile material is removed when such slope variations are employed than when the platen  51  sidewalls are uniformly sloped as in a smooth sidewall funnel-type configuration for platen  51 , although even a smooth-walled funnel-type configuration for a platen  51  is very useful in removing volatiles from engine lubricating oil.  
         [0047]     Volatiles separated from the oil enter the upper chamber  58  and collect over the platen  51  and beneath the top plate  41  and between the side walls  53  over the ledge projection  56 . Conveniently and preferably, vapors collecting in the upper chamber  58  are released through a check valve  63  preferably when the pressure in chamber  42  rises above a preset value.  
         [0048]     An electric resistance heating element  61 , preferably conventional, is circumferentially extended around an exterior, preferably longitudinally medially situated, sidewall portion of the platen  51 . Element  61  is conveniently connected to an electrical plug type connector  62  that is associated with and extends through a location in the side walls  53 . Exteriorly relative to the housing  52 , the plug type connector  62  is conventionally connectable with an electric power supply line  64 . The element  61  is preferably provided with thermostatic temperature regulating means, preferably conventional (not shown), whereby the platen  51  can be maintained at a predetermined elevated temperature. Conveniently, and preferably, the element  61  is operated by the 12 volt or other conventional power battery system associated with a vehicle in which the oil conditioning apparatus  32  is being used. Since the heating element  61  and associated components are located in lower chamber  59 , they are isolated from the upper chamber  58  and all fluids (including oil and volatiles) therein.  
         [0049]     As shown in  FIG. 1 , oil in conduit  31  is preferably filtered through a filter  35  before being charged to conduit  39 . Filtering can be accomplished by a conventional filter structure connected to conduit  31  whose output is connected to conduit line  39 . Filter arrangements such as taught in DePaul U.S. Pat. No. 6,083,406 can be employed, or otherwise, if desired.  
         [0050]     Oil filtering is preferably carried out at a flow rate of about 4 to about 10 gallons per hour at a pressure in the range of about 20 to about 100 psi, and preferably in the range of about 40 to about 75 psi. Preferably during the filtering particulates having particle sizes over about 5 microns are removed.  
         [0051]     In practice, one charges pressurized and filtered oil stream through the metering orifice or jet  43  into the chamber  58  and the distributing chamber  42 . Since chamber  42  is open to chamber  58 , these chambers are maintained at the same pressure. Pressure in chamber  58  is preferably maintained at atmospheric pressure through vent  63 . Thus passing the pressurized and filtered oil stream through the metering orifice or jet  43  depressurizes the oil stream and reduces its pressure to atmospheric pressure. In chamber  58 , the oil is moved to the upper, interior surfaces of the platen  51 . The movement can be accomplished by various means and methods. In the present preferred embodiment, the oil collected in the chamber  42  flows through the radially extending conduits  46  into the pipe  47  and out through the holes  48  to reach the inner upper surfaces of the platen  51 .  
         [0052]     Preferably, the platen  51  interior surfaces are heated during oil film contacting to a temperature in the range of from about 150 to about 210° F., and more preferably about 160 to about 200° F., although higher and lower temperatures can be used, if desired.  
         [0053]     At the bottom of the platen  51 , oil is drained away and returned to the engine lubricating oil.  
         [0054]     Those skilled in the art will readily appreciate that, particularly in the case of relatively small vehicular engines, the apparatus  32  can sometimes be employed as a replacement or alternative for a conventional oil filter assembly, such as the replaceable oil filter  28 , or the like.  
         [0055]     As indicated, in place of a platen having smooth, conically configured side walls, various alternative sidewall configurations in place of a platen  51  can be employed in the practice of this invention, such as illustrated, for example, in  FIGS. 8-17  where platens with sidewalls having various localized slope changes are illustrated. While in platen  51 , the localized slope changes are defined by a plurality of longitudinally spaced, continuously circumferentially extending, progressively or successive inturned ledge regions, the ledge regions can alternatively be outturned or inturned and can extend continuously and spirally, as shown in  FIG. 16 , or continuously and arcuately, as shown in  FIG. 17 , for example. The localized slope changes can be defined by a plurality of local offset regions (geometric designs) that each have geometrically configured perimeter portions that can be defined as depressions or as elevations that can be considered to be relative to a basic continuously extending platen side wall, such as illustrated in  FIGS. 8-15 , for example, where the offset regions are each defined by a plurality of straight edge portions, a plurality of curved edge portions, or a mixture of curved and straight edge portions. Platen side wall designs are preferably chosen for reasons of fabrication convenience and durably to be producable by stamping of sheet metal (preferably stainless steel) although oil resistant, heat resistant plastic materials can be used, if desired.  
         [0056]     Other and further equivalent embodiments and variations will be apparent to those skilled in the art without departing from the spirit and scope of this invention.