Abstract:
Improved oil reconditioning systems and methods are disclosed. One preferred system provides an oil purifier for an internal combustion engine for separating contaminants in an oil stream from the oil. The system may include a housing, an oil distributor, and a heating element. The housing may enclose a platen having an evaporation surface. The oil distributor may also be located in the housing and may be configured to receive an incoming oil stream. The oil distributor may have a discharge manifold for transforming the oil stream into a mist. The mist may be directed toward, and distributed over, at least a portion of the evaporation surface. The heating element may be in thermal communication with the platen. The evaporation surface may be heated to a temperature sufficient to volatilize the contaminants, resulting in a purified liquid oil which may be collected and reused with the engine.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority from co-pending application Ser. No. 10/647,093, filed Aug. 22, 2003 by DePaul, Publication No. 2005/0040077, entitled “LUBRICATING OIL RECONDITIONING DEVICE AND PROCESS,” which is hereby incorporated by reference in its entirety for all that it teaches without exclusion of any part thereof. 
     
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to oil reconditioning systems and processes. More specifically, the invention relates to an improved oil reconditioning system and method in which contaminated oil is deposited on an evaporation surface and volatile contaminants are separated from the oil. 
       BACKGROUND OF THE INVENTION 
       [0003]    Commonly used oil filters for internal combustion engines generally do not remove miscible liquid contaminants from the oil. Such contaminants include, but are not limited to, water and low boiling point organic chemicals whose presence in the lubricating oil may cause engine corrosion and wear. 
         [0004]    Oil lubricating systems for internal combustion engines that may remove such contaminants are described in U.S. Pat. Nos. 5,242,034, 5,707,515 and No. 6,083,406, each to Frank and/or Michael DePaul. Each of these patents are entirely incorporated herein by reference. Although these patents disclose oil reconditioning systems which are both functional and effective, new systems and methods would be desirable to improve efficiency and reliability. 
       DEFINITION OF CLAIM TERMS 
       [0005]    The following terms are used in the claims of the patent as filed and are intended to have their broadest meaning consistent with the requirements of law. Where alternative meanings are possible, the broadest meaning is intended. All words used in the claims are intended to be used in the normal, customary usage of grammar and the English language. 
         [0006]    “Approximately atmospheric pressure” means a pressure within the housing of the oil reconditioning system which is retained at a sufficiently low pressure in comparison to the pressurized oil stream initially supplied to the housing that the pressure in the housing does not substantially interfere with the formation of a mist from the oil stream when the oil stream is discharged from the oil distributor. 
         [0007]    “Contaminants” means any particles or chemicals whose presence in the oil stream may be detrimental to the operation of the engine, such as but not limited to water, non-oil particles, sludge, fuel, and low boiling point volatiles. 
         [0008]    “Mist” means a cloudlike aggregation of minute globules of liquids and particles, such as oil, water, and contaminants, suspended in air while moving from the oil distributor to the evaporation surface. 
         [0009]    “Evaporation surface” means any surface configured to receive the oil stream at or near an upper portion of the surface and configured to allow the oil to flow in a film toward a lower portion of the surface, and being capable of passing heat to the film from a heat source in contact with or near the surface. 
       SUMMARY OF THE INVENTION 
       [0010]    The present invention provides a system and method for refining oil. In one preferred system, an oil purifier for an internal combustion engine may be provided for separating contaminants in an oil stream from the oil. The system may include a housing, an oil distributor, and a heating element. The housing may enclose a platen having an evaporation surface. The oil distributor may also be located in the housing and may be configured to receive an incoming oil stream. The oil distributor may have a discharge manifold for transforming the oil stream into a mist. The mist may be directed toward, and distributed over, at least a portion of the evaporation surface. The heating element may be in thermal communication with the platen. The evaporation surface may be heated to a temperature sufficient to volatilize the contaminants, resulting in a purified liquid oil which may be collected and reused with the engine. 
         [0011]    In an additional preferred embodiment, the heating element is in physical contact with the platen. In an additional embodiment, the evaporation surface includes an upper portion which receives the oil mist and upon which the oil forms a film, and a lower portion which receives the oil film flowing toward it under the influence of gravity and from which the purified liquid oil is collected. 
         [0012]    In an additional preferred embodiment, the evaporation surface includes an inverse substantially conical shape having a plurality of substantially planar downwardly sloping sides. In an additional preferred embodiment, the evaporation surface lacks horizontal surfaces between the upper portion and the lower portion. In an additional preferred embodiment, the primarily planar side portions include horizontal grooves. In an additional preferred embodiment, the plurality of substantially planar side portions converge at transition points, and at least one of the transition points is rounded. 
         [0013]    In an additional preferred embodiment, the contaminants are discharged to the atmosphere and/or to the engine manifold. In an additional preferred embodiment, the liquid oil is collected and returned to an oil fill associated with the engine. In an additional preferred embodiment, a gap is provided between the platen and a bottom plate of the housing, and the liquid oil is collected on the bottom plate. In an additional preferred embodiment, the platen extends to a bottom plate of the housing, thereby separating the housing into an inner chamber and an outer chamber, and the liquid oil remains in the inner chamber. 
         [0014]    In an additional preferred additional embodiment, the oil purifier also includes a metering jet for regulating the oil stream prior to the oil stream being introduced to the oil distributor. 
         [0015]    In an additional preferred additional embodiment, the oil purifier also includes a three-stage filter configured to remove particles greater than three microns from the oil stream prior to the oil stream being introduced to the oil distributor. 
         [0016]    In an additional preferred additional embodiment, the housing is maintained at approximately atmospheric pressure and the distributor is configured to receive the oil stream at greater than atmospheric pressure. 
         [0017]    In another preferred embodiment, the system may include a housing, an oil distributor, a three-stage filter, and a heating element. The housing may enclose a platen having an evaporation surface. The oil distributor may also be located in the housing and may be configured to receive an incoming oil stream and to direct the oil over at least a portion of the evaporation surface. The heating element may be in thermal communication with the platen. The three stage filter may remove particles from the oil stream prior to the oil stream being introduced to the oil distributor. The first stage of the filter may be exterior to the second stage and configured to remove particles between about 25-40 microns. The second stage of the filter may be exterior to the third stage and configured to remove particles between about 10-25 microns. The third stage of the filter may be configured to remove particles greater than 3 microns. The evaporation surface may be heated to a temperature sufficient to volatilize the contaminants, resulting in a purified liquid oil which may be collected and reused with the engine. 
         [0018]    In one preferred method of practicing the invention a method of separating contaminants from an oil stream associated with an internal combustion engine is provided. The method may include the steps of introducing a contaminated oil stream from the engine to an oil distributor; transforming the contaminated oil stream to a mist; distributing the mist over an upper portion of an evaporation surface located in a housing; heating the evaporation surface; discharging the contaminants from the housing; collecting the purified oil from a lower portion of the evaporation surface; and reintroducing the purified oil to the engine. 
         [0019]    Other systems, methods, features, and advantages of the present invention will be, or will become, apparent to one having ordinary skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present invention, and be protected by the accompanying claims. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    The novel features which are characteristic of the invention are set forth in the appended claims. The invention itself, however, together with further objects and attendant advantages thereof, can be better understood by reference to the following description taken in connection with the accompanying drawings, in which: 
           [0021]      FIG. 1  is a diagrammatic view illustrating a lubricating system employing an embodiment of the oil purifier of the present invention which includes a purifier filter and a purifier chamber; 
           [0022]      FIG. 2  is a sectional view of the purifier chamber of  FIG. 1 , including a flow platen; 
           [0023]      FIG. 3  is a sectional view of the flow platen of  FIG. 2 ; and 
           [0024]      FIG. 4  is a block diagram of a preferred embodiment of a process of practicing the present invention. 
       
    
    
       [0025]    The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. In the drawings, like reference numerals designate corresponding parts throughout the several views. 
       DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0026]    Set forth below is a description of what are believed to be the preferred embodiments and/or best examples of the invention claimed. Future and present alternatives and modifications to the preferred embodiments are contemplated. Any alternatives or modifications which make insubstantial changes in function, in purpose, in structure, or in result are intended to be covered by the claims of this patent. 
         [0027]      FIG. 1  shows a lubricating system  100  employing a preferred embodiment of oil purifier  102  of the current invention. In lubricating system  100 , lubricating oil that has drained and collected in an oil pan  21  may be withdrawn by an engine lubricating oil pump  22  connected to conduit  23 . Conduit  23  may be associated with a lubricating oil screen structure  24  that may be located in the oil pan  21 . From pump  22 , the oil may be passed to a main lubricating oil stream successively through respective conduits  26  and  27  and into a replaceable oil filter  28  or the like. 
         [0028]    In filter  28 , the pressurized oil stream from conduit  27  may be filtered to remove filterable contaminants, such as particulates and sludge. The filtered oil may pass into a conduit system  33  through which it may be conveyed to engine bearings  34  for lubrication purposes. From the bearings  34 , the oil may drain (not detailed in  FIG. 1 ) and may again collect in the oil pan  21  for recycling through pump  22 . For a description of conventional portions of system  100 , see U.S. Patent Publication 2005/0040077 to DePaul, which is entirely incorporated herein by reference. 
         [0029]    A by-pass valve or proportional flow divider  104  may be placed between conduits  26  and  27 . The flow divider  104  may separate the oil stream into a main oil stream in conduit  27  and a bypass oil stream that may be introduced to conduit  31 . The flow divider  104  may include a number of passageways, or holes, for accurately regulating the amount of oil entering the bypass oil stream. The bypass oil stream that enters and flows through conduit  31  may be introduced to oil purifier  102 . Oil purifier  102  may include a purifier filter  106  and a purifier chamber  108 . 
         [0030]    The invention is not limited to any particular engine application. As non-limiting examples, the invention may be used with automobile engines, marine engines, truck engines, construction equipment engines, recreational vehicle engines, agricultural engines, and other types of engines, including any diesel engines that employ oil for lubricating and/or cooling. In one embodiment, the bypass oil stream may constitute particular application, in the case of a typical truck engine having approximately a 40-quart lubricating oil capacity, a 14% bypass permits sufficient oil purification through the current invention, while ensuring sufficient main oil stream flow for lubricating engine components, such as bearings  34 . 
         [0031]    Under pressure generated by pump  22 , the bypass oil stream may be introduced to oil purifier  102  and may be processed as described herein, first to separate filterable contaminants and then to separate volatile, i.e. low boiling point, contaminants from the bypass oil stream. The resulting processed and purified oil may exit from oil purifier  102  through interconnecting conduit  36 , which may be a 0.75-inch diameter conduit. In one embodiment, conduit  36  may allow the purified bypass oil stream to pass to oil filter  110  for the engine for recycling and reuse in engine lubrication. In another embodiment, conduit  36  may allow the purified bypass oil stream to pass into oil pan  21  (path not shown in  FIG. 1 ). 
         [0032]    The volatile contaminants separated from the bypass oil stream in purifier chamber  108  may be discharged from oil purifier  102  into the atmosphere through vent  202  (shown in  FIG. 2 ), and/or into a conduit  37  for conveyance to the engine intake manifold (not shown), or otherwise, as may be desired. Vent  202  may allow vapor—such as, but not limited to, evaporated water, oil and contaminates—to exit purifier chamber  108  while restricting the flow of oil from purifier chamber  108 . Vent  202  may also maintain approximately atmospheric pressure in purifier chamber  108  in order to promote evaporation of contaminates. 
         [0033]    Oil purifier  102  may be provided for retrofitting in combination with a previously manufactured vehicular engine or the like using a kit or the equivalent. Such a kit may comprise, for example, flow divider  104 , purifier filter  106 , purifier chamber  108 , and interconnecting conduit components, such as conduits  31  and  36 . 
         [0034]      FIG. 2  shows a sectional view of purifier chamber  108  of  FIG. 1 . In purifier chamber  108 , contaminants, such as low boiling point volatiles, are separated from the bypass oil stream. Preliminarily, purifier filter  106  filters the bypass oil stream to remove particulates, including sludge. The filtered bypass oil stream enters purifier chamber  108  through a conduit  204  that extends in gas-tight relationship through a side portion of a top cap plate  206 . The bypass oil stream is introduced to an inner chamber  208  through a metering jet  209  and an oil distributor, such as spray nozzle  210 . Metering jet  209  may reduce and/or regulate the flow of the bypass oil stream, and may result in more efficient evaporation of contaminants in purifier chamber  108 . 
         [0035]    Inner chamber  208  is separated from outer chamber  212  by a platen  214  having an evaporation surface  214   a . Evaporation surface  214   a  includes an upper portion  214   b  and a lower portion  214   c.    
         [0036]    As the pressurized bypass oil stream exits spray nozzle  210 , the oil stream is exposed to approximately atmospheric pressure in inner chamber  208 . In one embodiment, the pressure drop is approximately 75-100 psi. Spray nozzle  210  may be configured to cause the bypass oil stream to form a mist as it exits spray nozzle  210 . Spray nozzle  210  may include a discharge manifold having a plurality of slits, for example 4 or 5 slits, to allow the bypass oil stream to form a plurality of mist paths  210   a  that may form a generally uniform distribution pattern. In one embodiment, metering jet  209  and spray nozzle  210  are configured to provide a mist over a broad circular path over the upper portion  214   b  of evaporation surface  214   a.    
         [0037]    The upper portion  214   b  of evaporation surface  214   a  is located to receive the oil distribution pattern from spray nozzle  210 , which may be take the form of a mist and/or a stream, and to allow the oil to condense and/or deposit on upper portion  214   b . In one embodiment, evaporation surface  214   a  is located and configured in coordination with spray nozzle  210  so that the mist is generally uniformly deposited on upper portion  214   b  of evaporation surface  214   a  where it may form a film. Contaminants within the bypass oil stream may remain in the mist and/or may be deposited on upper portion  214   b  with the oil film. 
         [0038]    The top cap plate  206  may be secured to a lower housing  52 . Housing  52  and cap plate  206  may be formed of cast, machined metal, and platen  214  may be formed from stamped, welded sheet metal, preferably stainless steel. 
         [0039]    In a preferred embodiment, and referring now to  FIG. 2 , evaporation surface  214   a  may include a plurality of varying, downward-sloped surfaces  214   d , which may but need not have varying slope angles from the upper portion  214   b  to the lower portion  214   c . The varying downward-sloped surfaces  214   d  may converge at angled transition points  214   g . Evaporation surface  214   a  may include a plurality of generally horizontal grooves (designated in  FIG. 2  by lines  214   f ). Grooves  214   f  may beneficially reduce the speed at which the oil film travels from upper portion  214   b  to lower portion  214   c . As the oil descends from the upper portion  214   b , its exposed surface area declines, which may aid in removing volatiles from the oil being processed. Also, as the oil descends, it is concentrated at lower portion  214   c , which is desirable for oil collection purposes. The shape of evaporation surface  214   a  is believed to result in more efficient and faster evaporation of volatiles from the oil film than previous shapes. In addition, evaporation surface  214   a  is believed less likely to cause undesirable pooling of oil, and formation of oil deposits, than previous shapes. An upper edge portion of platen  214  may be provided with an out-turned flange  214   e . The lower housing  52  that may contain platen  214  may have generally cylindrical side walls  53  that may be joined unitarily at a bottom edge portion to a dome configured bottom plate  54 . An out-turned rim flange  206   a  located on perimeter portions of top plate  206  may mount with machine screws or the like over, and sealingly close, with the aid of a seal (not shown), the upper edge portions of cylindrical side walls  53 , thereby completing an enclosure for purifier chamber  108 . 
         [0040]    Ledge projection  56  circumferentially extends about inside wall portions of sidewalls  53  in downwardly spaced, adjacent relationship to the upper edge portions of sidewalls  53 . Out-turned flange  214   e  rests against the flattened upper face of ledge projection  56  of evaporation surface  214 . Flange  214   e  may be mounted to ledge projection  56  by a plurality of circumferentially spaced machine screws  216  or the like. Thus, platen  214  may divide at least the upper portion of purifier chamber  108  into an inner chamber  208  and an outer chamber  212 . Preferably at the lowest point of bottom plate  54 , a (e.g.) 0.75-inch drain allows the purified oil stream to exit oil purifier  102  through conduit  36 . 
         [0041]    In one embodiment, a gap  218  is left between platen  214  and bottom plate  54  in order to allow oil to pool after flowing from evaporation surface  214   a . In another embodiment, the gap is omitted and platen  214  extends to bottom plate  54 . 
         [0042]    Oil that exits spray nozzle  210  as a mist may deposit on upper portion  214   b  of evaporation surface  214   a , forming a thin film that moves downward by gravity over heated portions of evaporation surface  214 . Since the evaporation surface may include surface regions defining a plurality of slope changes, the oil flowing thereover may experiences a variable flow rate and a variable film thickness as it progresses to lower portion  214   c  of evaporation surface  214 . Such variations are generally preferred and are believed to be desirable for purposes of enhancing the separating and removing of volatile materials from the oil being so treated. It is believed that more volatile material is removed when such slope variations are employed than when evaporation surface  214   a  is uniformly sloped. 
         [0043]    Volatile contaminants separated from the bypass oil stream enter inner chamber  208  and collect over platen  214  and beneath top plate  206 . Conveniently and preferably, vapors collecting in inner chamber  208  are released through valve  202 . In one embodiment, valve  208  includes a check valve portion to prevent loss of oil from purifier chamber  208  in the event of a blockage or hindrance of the bypass oil stream. 
         [0044]    An electric resistance heating element  61  may be circumferentially extended around platen  214  and may be separated from inner chamber  208  by evaporation surface  214 . Heating element  61  may be connected to an electrical plug type connector  62  that is associated with, and extends through, a location in side walls  53 . Exteriorly relative to lower housing  52 , plug type connector  62  may be conventionally connected to an electric power supply line  64 . Heating element  61  may preferably be provided with a thermostatic temperature regulating means (not shown) so that at least a portion of evaporation surface  214   a  may be maintained at an elevated temperature. Preferably, heating element  61  is operated by a 12-volt battery, or other conventional power battery system, associated with a vehicle in which oil purifier  102  is being used. Since heating element  61  and its associated components are located on the opposite side of platen  214  from evaporation surface  214   a , they may be isolated from inner chamber  208  and fluids (including oil and volatiles) therein. 
         [0045]    As shown in  FIG. 1 , in one embodiment the bypass oil stream is filtered by filter  106  before being charged to purifier chamber  108 . Filtering may be accomplished by a conventional filter and filter arrangements. More preferably, filtering may be accomplished through filters described in DePaul U.S. Pat. No. 6,083,406. In one preferred embodiment, a 3-stage filter  106  is employed. 3-stage filter  106  may include a first-exterior stage filter configured to filter contaminants between about 25-40 microns, a second-intermediate stage filter configured to filter contaminants between about 10-25 microns, and a third-internal stage filter configured to filter contaminants between about 3-10 microns. Filter  106  may employ an external-to-internal flow pattern such that larger particles are captured in the first-exterior and second-exterior stages, and smaller particles are captured in the third-interior stage. In one embodiment, an expanded third-interior stage is believed to provide more complete filtration and result in longer filter life. 
         [0046]    In one embodiment, the bypass oil stream may flow at rate of about 4-to-6 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 3 microns are removed. It is believed that substantially all volatile contaminants may be removed from the oil in an engine that employs the invention. 
         [0047]    In one method of practicing the invention, a first step includes charging the pressurized and filtered bypass oil stream through spray nozzle  210  into inner chamber  208 . Pressure in inner chamber  208  is preferably maintained at approximately atmospheric pressure through vent  202 . Passing the pressurized and filtered bypass oil stream through spray nozzle  210  depressurizes the bypass oil stream, reduces its pressure to approximately atmospheric pressure, and generally permits the bypass oil stream to form a mist. In upper chamber  208 , the oil is moved to upper portion  214   b  of evaporation surface  214   a , where the oil generally forms a film on evaporation surface  214   a . The film generally flows from upper portion  214   b  to lower portion  214   c . Contaminants in the bypass oil stream may be volatilized through the misting process and/or through evaporation from evaporation surface  214   a . The purified oil bypass stream may then be introduced to conduit  36 . 
         [0048]    In one embodiment, at least a portion of evaporation surface  214   a  is heated to a temperature in the range of from about 150-210° F., and more preferably about 160-200° F., although higher and lower temperatures may be used, if desired. 
         [0049]    Those skilled in the art will readily appreciate that, particularly in the case of relatively small vehicular engines, oil purifier  102  may sometimes be employed as a replacement or alternative for a conventional oil filter assembly, such as replaceable oil filter  28 , or the like. 
         [0050]    In place of evaporation platen  214   a  having the shape illustrated in  FIG. 1 , various alternatively shaped platens may be used in various embodiments of the invention. Some of those alternative shapes are illustrated in U.S. Published Patent Application No. 2005/0040077. An alternatively shaped platen  302  is also illustrated in  FIG. 3 . Platen  302  may include an evaporation surface  302   a  having an upper portion  302   b , a lower portion  302   c , a plurality of downward-sloped surfaces  302   d , an outturned flange  302   e , and horizontal grooves  302   f . The convergence of the downward sloped surfaces may have rounded edges  302   g  from upper portion  302   b  to lower portion  302   c.    
         [0051]    Another preferred method of practicing the invention is further illustrated in  FIG. 4 .  FIG. 4  shows a method  400  of separating contaminants from an oil stream associated with an internal combustion engine. The method  400  may include a step  402  in which a contaminated oil stream is introduced to the purifier chamber  108 . In step  404 , the contaminated oil stream may be regulated through a metering jet  209 . In step  406 , the contaminated oil stream may be transformed into a mist, for example, by introducing the oil stream to an oil distributor such as spray nozzle  210 . Various steps during the process, such as in step  406 , may result in contaminants being separated from the oil stream. In step  408 , contaminants may be discharged, for example, through conduit  37 . 
         [0052]    In step  410 , the mist may be distributed over an upper portion of an evaporation surface located in a housing, where the oil may flow from the upper portion to a lower portion. For example, the mist may be distributed over upper portion  214   b  of evaporation surface  214  located in housing  52 . In step  412 , the evaporation surface may be heated. For example, heating element  61  may be used to heat evaporation surface  214 . In step  414 , the oil may flow from an upper portion of the evaporation surface to a lower portion. For example, the oil may flow from upper portion  214   b  to lower portion  214   c . In addition to step  406 , steps  410  to  414  may also result in contaminants being separated from the oil stream. In step  416 , the purified oil may be collected and reintroduced to the engine. For example, the purified oil may be collected on bottom plate  54  and returned to the engine through conduit  36 . 
         [0053]    Where processes and methods are described, it is not contemplated that the steps of the method are necessarily required to be performed in the order in which they are described. The above description is not intended to limit the meaning of the words used in the following claims that define the invention. For example, while several possible designs have been described above, persons of ordinary skill in the art will understand that a variety of other designs still falling within the scope of the following claims may be envisioned and used. It is contemplated that these or other future modifications in structure, function or result will exist that are not substantial changes and that all such insubstantial changes in what is claimed are intended to be covered by the claims.