EP0098866B1 - Zentrifugalseparator - Google Patents

Zentrifugalseparator Download PDF

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Publication number
EP0098866B1
EP0098866B1 EP83900493A EP83900493A EP0098866B1 EP 0098866 B1 EP0098866 B1 EP 0098866B1 EP 83900493 A EP83900493 A EP 83900493A EP 83900493 A EP83900493 A EP 83900493A EP 0098866 B1 EP0098866 B1 EP 0098866B1
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EP
European Patent Office
Prior art keywords
oil
housing
air
rotor
chamber
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP83900493A
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English (en)
French (fr)
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EP0098866A1 (de
Inventor
Henry Woods Martin
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AE PLC
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AE PLC
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Publication date
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Priority to AT83900493T priority Critical patent/ATE20315T1/de
Publication of EP0098866A1 publication Critical patent/EP0098866A1/de
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Publication of EP0098866B1 publication Critical patent/EP0098866B1/de
Expired legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B04—CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES
    • B04B—CENTRIFUGES
    • B04B5/00—Other centrifuges
    • B04B5/005—Centrifugal separators or filters for fluid circulation systems, e.g. for lubricant oil circulation systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
    • F01M1/00—Pressure lubrication
    • F01M1/10—Lubricating systems characterised by the provision therein of lubricant venting or purifying means, e.g. of filters
    • F01M2001/1028—Lubricating systems characterised by the provision therein of lubricant venting or purifying means, e.g. of filters characterised by the type of purification
    • F01M2001/1035—Lubricating systems characterised by the provision therein of lubricant venting or purifying means, e.g. of filters characterised by the type of purification comprising centrifugal filters

Definitions

  • This invention relates generally to centrifugal separators, and more particularly to centrifugal separators of the self-powered type that can be used for removing contaminants from a liquid system such as the lubricating oil system of internal combustion engines.
  • these filters can be classified as one of two types, either full flow or bypass filters.
  • a porous type filtering element is used, and it is placed directly between the oil pump and the remainder of the lubricating system so that all of the oil passes through the filter.
  • Such filters generally tend to have filtering elements of relatively large porosity, not only because they must pass a relatively high volume of oil with a minimum of pressure drop across the filter, but also because as the contaminants are filtered out of the oil and remain on the filter element, they tend to reduce the size of the pores, which further limits the filtering action and increases the problems of rate of oil flow through the filter.
  • the relatively large porosity of the filter elements there are a number of fine-grained particulate materials which are not filtered out of the oil because they are too small to be retained on the filter element.
  • the other type of oil filter is the bypass type in which a certain amount of oil as it leaves the oil pump is diverted into a filter from which it returns to the oil sump to be recirculated through the oil pump without passing through the remainder of the lubricating system. While such bypass filters filter only a portion of the oil being pumped, they can be very efficient in terms of removing very small particulates because they operate under a high pressure drop between the supply pressure and the oil sump.
  • bypass filters may be of the mechanical type having a porous filter element
  • centrifugal type filters are quite advantageously used in such applications.
  • a typical such centrifugal filter is the one shown in Beazley patent No. 3,432,091, which includes a hollow casing within which is rotatably mounted a rotor element having an internal chamber and an outer wall. The casing is connected directly to the sump or drain, while high pressure oil is directed into the interior of the rotor. As the rotor fills with pressurized oil, the oil passes downwardly to a pair of diametrically located discharge orifices or jets having a restricted diameter.
  • centrifugal filters of this type function normally, they will remove a very high proportion of the contaminants and keep the lubricating oil from deteriorating.
  • filter cleaning or replacement should be done at certain regular intervals, and if the filter has been functioning in its intended manner, there should be a predictable amount of accumulated sludge in the filter rotor.
  • the filter has not been functioning in the intended manner. This presumably results either from the rotor not reaching the intended operating speed of rotation or by the fact that perhaps at certain times the rotor was not even spinning at all.
  • the present invention provides an improved arrangement for preventing possible build-up of return oil in the filter housing by introducing a controlled amount of air at a pressure above atmospheric into a chamber below the rotor to prevent the possibility of the oil level rising upward until it may contact the rotor.
  • the invention provides a method of removing contaminants from a fluid by centrifuging, wherein the fluid is supplied under pressure to the interior of a rotor in a housing and leaves the rotor by way of a jet such that the reaction force causes the rotor to rotate, air being admitted to the interior of the housing, including a space below the rotor, to vent suction created during drainage, characterised in that the air is supplied at a pressure above atmospheric to assist drainage of fluid away from the lower end of the housing.
  • a substantially constant air pressure is maintained in the housing. It is also desirable that air is supplied substantially only when the level of the fluid waiting to drain away from the housing rises above a predetermined level and that air is supplied via a float valve.
  • the invention provides a centrifugal oil cleaner assembly comprising a housing defining a chamber, a rotor in the chamber, means for supplying oil to be cleaned under pressure to the interior of the rotor, jets to discharge oil from the rotor into the chamber and by reaction to cause the rotor to rotate, an oil outlet for draining oil away from a space in the lower end of the housing, and a valve for admitting air to the interior of the housing to vent suction created during drainage, characterised by means communicating with the interior of the housing for connection to a supply of air at a pressure above atmospheric, said means including said valve and said valve being arranged to admit said air to the interior of the housing when the level of the oil waiting to drain away from the lower end of the housing is above a predetermined level.
  • the invention provides a centrifugal oil filter system for a machine having an oil pump for supplying oil under pressure and a sump, said filter system including a housing defining a chamber, a drain line between the lower end of the housing and the sump, an oil pressure line between the oil pump and the housing, a rotor in said chamber having an interior arranged to be supplied with oil under pressure from the pressure line, the rotor having jets to discharge oil into the chamber and by reaction cause the rotor to rotate about a substantially vertical axis, and means for admitting air to the interior of the housing to vent suction created during drainage, characterised in that the housing is connected by said means to a source of air at a pressure above atmospheric, to replace air entrained in the oil returning to the sump and thereby prevent a build up of oil within the chamber.
  • a regulator housing mounted directly below the filter housing, and which includes an air valve which is connected to a suitable source of air pressure such as an air brake compressor or other pump.
  • a float is mounted within this regulator chamber and is actuated by the oil level within the chamber. As long as this oil level remains low, the air valve is closed and no additional air is admitted to the chamber. However, if the oil level begins to rise, as will occur when the entrainment of air from the jets within the return oil removes air from the filter housing, the oil level will begin to build up and raise the float.
  • the float When the float reaches a predetermined position, it will open the air valve so that air from the pressure source enters the regulator chamber, and hence, by its direct connection, the interior of the filter housing. Because of this positive action, the air pressure within the filter housing will rise above atmospheric and increase the force on the oil within the return line, to increase the rate of return flow and lower the oil level within the regulator chamber. It has been found that, regardless of the pressure of the air source, it is never necesssary to increase the pressure within the filter housing by more than a few psi, so that the pressure drop of oil across the rotor orifices or jets remains substantially the same, to allow the filter to function in the normal manner. However, it is noted that the amount of air that is added through the regulator is relatively small in volume, and corresponds only to the amount of entrained air removed through the oil flowing back to the sump.
  • Another advantage of this invention is that it has been found possible to greatly reduce the diameter of the return line from the air regulator back to the sump.
  • the return lines formerly were sized to allow a free drain without any pressure assist other than normal forces of gravity, since it was always a procedure to mount the filter substantially above the oil level in the sump.
  • Using the regulator of this invention it is now possible to use a return line that is not much larger than, and may even be equal in size to, the oil supply line from the engine oil pump.
  • the mounting arrangement possibilities are greatly increased, since the use of a smaller drain hose provides greater flexibility for the hose, and therefore more convoluted paths of the hose, without creating undesirable restrictions against return or drain flow of the oil.
  • it is even possible to mount the filter below the level of oil in the sump since there is now a small positive pressure which can overcome the forces of gravity and possibly force the oil to the return line into the sump.
  • Still another advantage of this invention is that is may be incorporated into centrifugal filters of the disposable type such as those shown in U.S. patents Nos. 4,106,689 and 4,165,032.
  • the float may be mounted within the disposable container -and so arranged that it controls the actuation of an air valve in an air supply line connected directly to the casing of the disposable filter. Since the air valve can be mounted directly in the casing, this means that when the filter is full it can be removed and replaced very quickly, and therefore requires only the removal of the casing in its connection lines as well as the disconnection and reconnection of the air supply line, so that the down-time of the machinery with which the filter is used is held to a minimum.
  • centrifugal filter is used in this specification, it will be appreciated that true filtration need not take place and that separation of contaminants is effected by centrifugal force.
  • the centrifugal separator or filter 10 includes a lower housing member 11 and an upper housing . member 12 which have flanges 13 and 14, respectively, which fit together in interlocking, telescoping relationship.
  • a clamp 16 firmly holds the two members together and an 0-ring seal 15 prevents any fluid leakage out of this joint.
  • the upper and lower housings 12 and 11 define a housing chamber 18, which terminates at its lower end in a drain passage 19 extending downwardly and out through the bottom of the lower housing member 11.
  • a rotor 20 which includes a rotor base member 21 having an upwardly extending, peripheral wall 22.
  • the rotor also includes a cover 24 having a top wall 25 and a downwardly extending peripheral sidewall 27 which terminates in an enlarged flange 28 adapted to fit over the upper end of the peripheral wall 22, and a suitable 0-ring seal 31 is provided at this joint to prevent leakage of the oil within the rotor 20 outwardly into the housing chamber 18.
  • the rotor In order to mount the rotor 20 for rotation within the housing chamber 18, the rotor is provided with a spindle 34 which at its lower end extends through an aperture 35 in the rotor base 21. On the lower side of the base 21 is a thrust washer 37 which fits against a flange 38 on the lower end of the spindle.
  • the spindle 34 extends upwardly through an aperture 41 in the rotor cover top wall 25, and above the aperture 41 a nut 43 is threadedly engaged with a threaded portion on the spindle 34 so that, by tightening the nut 43, the rotor cover 24 is forced downwardly to firmly engage the base member at the seal 31, and force the base member against the thrust washer 37 and flange 38, so that the spindle 34 becomes an integral part of the rotor 20, to rotate therewith.
  • the rotor 20 is mounted on a pair of bearings supported in the upper and lower housing members 12 and 11, respectively, and, accordingly, at its lower end, the spindle 34 has a journal portion 45 which fits within a bearing member 47 mounted in a recess 48 formed in projecting boss 49 on the lower housing member 11.
  • the bearing 47 has an outwardly extending flange 50 above the recess 48 arranged to abut against the thrust washer 37 and support the weight of the rotor.
  • the top wall 52 of upper housing member 12 is provided with a formed recess 53 which receives a radial bearing 54 and thrust bearing 55 to journal the upper end 57 of spindle 34.
  • the spindle 34 has a bore 59 of uniform diameter therethrough, so that the hydraulic forces at each end of the spindle 34 at the bearing recesses 48 and 53 are balanced, and the thrust washer 37 needs support only the weight of the rotor 20 independent of any pressure forces.
  • Oil is supplied under pressure to the separator 10 by a line from the oil pump of an internal combustion engine or other machine (not shown) and this line is connected to an inlet bore 62 formed in the lower housing member 11.
  • the oil then passes through an isolating valve 63 and passage 64 to the bearing recess 48, from which it can enter the bore 59 and spindle 34.
  • the isolating valve 63 is spring-biased to a closed position under low oil pressure conditions, such as at engine idle, so as not to rob oil from the engine bearings. This valve is optional and is not used in many applications.
  • a cylindrical screen 71 extends coaxially with the spindle 34 and spaced away therefrom between the deflector cup 67 at the upper end in a conical baffle 73 at the lower end.
  • Conical baffle 73 extends downwardly and outwardly to fit within an annular groove 74 formed in the rotor base member 21.
  • the separator 10 must be mounted in a generally vertical position for optimum performance, so that there is a minimum of unbalanced forces acting on the rotor 20. Accordingly, the lower housing member is secured to the mounting bracket 90, which in turn is secured to a frame rail indicated at 92 of a motor vehicle or other support by means of suitable bolts 93.
  • the return flow of oil from the housing chamber 18 to the sump of the internal combustion engine was performed by providing a suitable fitting connected to the drain passage 19 so that the oil could then pass by a suitable flexible hose or pipe to the oil pump.
  • this return line had to be of relatively large diameter because, for optimum speed of the rotor, no oil could be allowed to accumulate within the housing chamber 18, which is normally filled with air which may enter through the drain line by counterflow from the sump or by means of an air bleed valve, which is no longer required with the present invention.
  • the return line Since there is substantially no pressure drop between the housing chamber 18 and the oil sump, the return line must be of relatively large diameter to prevent fluid from building up within the housing chamber 18, because if the level does build up where the oil can reach the level of the rotor base member 21, the frictional drag will cause the rotor to rotate at a much lower speed, thereby greatly decreasing the centrifugal forces required to produce the effective filtering action of these separators, and consequently little or no particulate matter will be removed from the lubricating oil.
  • the jets of oil pass outwardly at high velocity through the orifice 78 - and this velocity can be quite high because substantially all of the pressure drop between the supply line and atmosphere takes place across the orifice 78 - the oil impinges upon the interior wall of the lower housing member 11.
  • the jet of oil is broken up into a fine spray of droplets, which tend to entrain or dissolve the air therein, either by actual solution or by forming a foam, and as the oil with the entrained air passes back to the sump, it necesssarily tends to cause the pressure within the housing chamber 18 to drop so that the oil level will rise upwardly within the drain passage 19.
  • the present invention solves this problem by admitting additional air into the housing chamber 18 to replace the air removed by the entraining action of the oil, to positively prevent the oil level from rising to contact the rotor base member 21.
  • a regulator housing 95 having a bottom wall 96 and sidewalls 97 defining a chamber 99.
  • the regulator housing 95 is positioned below the mounting bracket 90, and has a top surface 101 which is clamped against a gasket 104 to the lower side of the mounting bracket 90.
  • the separator 10 can be mounted on the upper side of the mounting bracket 90 using a gasket 103 and, by extending bolts 106 through the lower housing member 11, the mounting bracket 90, and the regulator housing 95, the entire assembly can be clamped together in a unitary relationship.
  • a drain opening 108 is provided in the regulator housing bottom wall 96, and to this is connected a return line to the engine sump.
  • the regulator housing 95 also includes an air inlet fitting 111 to which is connected an air supply line from a suitable source, such as an air brake compressor or the like. Directly above the inlet 111 is a reduced diameter threaded bore 112 within which is mounted a valve 113 having an upwardly projecting valve stem 114.
  • This valve may be constructed in the manner of an ordinary tire valve, which is normally closed so that the air at the inlet 111 cannot pass the valve. However, whenever the stem 114 is depressed, the valve is opened to allow the passage of air.
  • valve stem 14 Directly above the valve stem 14 is a bore 116 within which is mounted a valve rod 118 having a smaller diameter than that of bore 116, to allow the passage of air between the valve rod and bore upwardly into the regulator chamber 99.
  • a float arm 121 carried by a pivot pin 122 secured in the regulator housing adjacent the upper end of valve rod 118.
  • the float arm 121 is connected to a hollow float 124, which is free to move within the chamber 99 as the arm 121 pivots about the pivot pin 122.
  • the float arm also has an actuating end 126 which extends in the opposite direction from the pivot pin 122 to a point above the valve rod 118.
  • the float 124 when there is no oil within the regulator chamber 99, the float 124 normally is in a lowered position so that the actuating end 126 of float arm 121 is spaced above the valve rod 118. Since the valve stem 114 is in a closed position, no air enters the chamber through an inlet 111.
  • the filter When the filter is operating so that oil is discharged into the housing chamber 18 to flow downwardly through the drain passage 19, oil may build up within the regulator chamber 99, and if the oil level begins to rise because of insufficient flow rate through the drain opening 108, the float may rise to the position shown in phantom lines at 128.
  • the actuating end 126 of float arm 121 presses downward on the valve arm 118 to -depress the valve stem 114.
  • air enters through the inlet 111, past the valve 113 and valve rod 118, into the chamber 99.
  • the presence of this air in the chamber 99, and hence in chamber 18, will assist the return flow of the oil and the float 124 may cycle upwardly and downwardly to admit the amount of air required to make up for the air removed by entrainment through the return flow of the lubricating oil.
  • the return line connected to the drain opening 108 is of quite large diameter, the pressure within the regulator chamber 99 and housing chamber 18 will still be at subsantially atmospheric pressure.
  • the separator 10 may be located below the oil level in the engine sump, so that there may be a tendency for reverse flow of the oil drain line.
  • the regulator will then admit air into the housing chamber 18 and the pressure may tend to build up above atmospheric pressure to produce the necessary pressure forces to cause a sufficient rate of flow to the sump through the return line to keep the oil level in the regulator housing so that the float is positioned below the phantom line position shown at 128. It should be pointed out that this arrangement now allows the filter to be mounted below the sump level and when the engine is not running, the balance of forces may actually cause the entire housing chamber 18 to be filled with oil by return flow through the drain line. This causes no undesirable condition, but merely a slight delay in the operation of the filter when the engine is started.
  • the housing chamber 18 may be full of oil when the engine starts, the float will be in the upper position and air will immediately enter through the inlet 111, and hence into the housing chamber 18. This then drives the oil level down and when it drops below the level of the rotor base member 21, the rotor may then begin to rotate in the customary manner and the oil level will continue downward until stabilized by the position of float 124 in the manner previously described.
  • the source of air connected to the air inlet 111 need have a pressure only a small differential above that required within the housing chamber 18.
  • the maximum pressure expected within the housing 18, either because of a low position of the filter or a relatively small drain line may in the range of 20,7 to 69 kPa (3 to 10 psi)
  • a pressure source in the range of 103,5 to 138 kPa (15 to 20 psi) may be sufficient, although higher pressures, such as those of air brake compressors, may also be used so long as such pressures are within the capacity of the valve 113.
  • the volume of air required is relatively small because the volume of air required is only that needed to make up for the air removed by entrainment in the oil. That is, the volume of air that may flow through the filter is relatively small compared to the volume of oil flowing through the separator between the inlet bore 62 and the drain opening 108.
  • the volume of air does not assist in the return flow except to make up for the entrained air and, for that reason, it is necessary to allow the float 124 to position itself where the valve 113 can close, since the failure of this valve to close at a stable point would result in an excess flow of air into the system, which would tend not only to pressurize the chamber 18, which would reduce the filter's efficiency because the oil pressure drop across the orifice 78 would be reduced and thereby reduce the reaction forces causing the rotors to spin, but also because such excess air might cause foaming or frothing of the oil in the sump, which could adversely affect the lubrication of the internal combustion engine.
  • the invention is also applicable not only to the centrifugal separators of the permanent type, which are intended to be disassembled, cleaned, and thereafter reassembled, but also to centrifugal separators of the disposable type, such as those shown in U.S. patents Nos. 4,106,689 and 4,165,032.
  • the centrifugal filter shown in FIGS. 2 and 3 generally conforms to that shown in the above patents except for the additional structure for admitting air into the housing and for the elimination of the air bleed valve shown in those patents, which is not required with the present invention.
  • the separator 140 includes a thin sheet metal housing shell 141 defining a shell chamber 142 and closed at the one end by a cover 143 joined to the shell 141 along a suitable seam 144.
  • a cover 143 Within the cover 143 is a rigid support disc 145, while the cover 143 also carries an annular sealing gasket 147.
  • An inlet fitting 148 is centrally mounted on the support disc 145 to engage a suitable fitting 149 formed on the engine block 150 against which the gasket 147 seals when the separator 140 is installed in place.
  • the inlet fitting 148 also serves to support a spindle 152, the lower end of which is resiliently supported by a helical compression spring 154 abutting at the one end against the lower end of spindle 152 and at the other end against an outlet fitting 156 secured in the closed bottom end of the housing shell 141. It will be understood that the outlet fitting 156 is connected back to the sump of the engine in the usual manner.
  • a rotor 158 having a central tube 159 rotatably journaled on bearings 160 and 161 at the upper and lower ends, respectively, of the spindle 152.
  • the rotor 158 has a shell 164 which, in combination with the rotor tube 159, forms a sealed enclosed rotor chamber 165 which, in operation, will be pressurized with respect to the shell chamber 142.
  • the rotor 158 includes a lower wall 166 adjacent the lower bearing 161 which is provided with a pair of downwardly extending, hollow projections 167 which carry the jet openings 168 to rotatably drive the rotor 158 within the separator as a result of the pressure admitted through the inlet fitting 148.
  • centrifugal separator described above is substantially the same as that disclosed in U.S. patent No. 4,106,689, except that, as shown in FIG. 2, the housing shell 141 has a greater vertical extent and the support spring 154 is likewise longer, to increase the space available within the housing shell 141 below the rotor 158.
  • a float arm 170 which may be made of a thin, flexible sheet material and has an end 171 secured to the inside of the housing shell 141.
  • the float arm 170 has a pair of fork arms 173 passing on each side of the spring 154 and to which is secured a hollow float 175.
  • Another inlet fitting 177 is secured in the lower wall of the housing shell 141 adjacent the float arm 171 and is provided with a valve seat and 178 within the shell chamber 142.
  • a suitable valve member 180 such as a molded piece of rubber, is secured to the float arm 170 adjacent the valve seat 178.
  • Another inlet tube 182 is connected to the fitting 177 and through a suitable check valve 183 to a source of air under pressure.
  • the disposable type of the centrifugal separator shown in the embodiment of FIGS. 2 and 3 functions in the same manner as the embodiment of FIG. 1. Furthermore, when the centrifugal filter becomes full of sediment within the rotor 158, it is simply removed and replaced with a new one by unscrewing it from the fitting 149 after disconnecting tubes from the outlet fitting 156 and the air inlet fitting 177, and after a new separator is attached to the fitting 149, these tubes are reattached in the usual manner.
  • FIG. 4 Another embodiment of a disposable centrifugal filter is shown in FIG. 4, which eliminates the separate connection for the outlet fitting 156 of the embodiment of FIGS. 2 and 3.
  • the separator 201 includes a housing or shell 203 which is generally cylindrical in shape and is closed by a cover 205 at the one end, secured to the shell 203 along a seam 206.
  • At outer support disc 208 is secured inside the shell 203 adjacent the cover 205, while the latter also mounts an annular gasket 209.
  • An inlet fitting 210 is mounted in the support disc 208 at the center thereof for engagement with a fitting 212 carried on an engine block 213.
  • the block 213 also has an annular boss 214 against which the gasket 209 makes sealing engagement.
  • An inlet fitting 210 is fully threaded in the fitting 212. Also provided in the engine block 213 are drain passages 216 leading to the sump of the engine and communicating with the annular space between the fitting 212 and the annular boss. 214. Likewise, apertures 217 are formed in the outer support disc 208, as will be explained in greater detail hereinafter.
  • An inner support disc 219 is also mounted within the shell 203 a spaced distance inwardly from the outer support disc 208 and extending generally parallel thereto.
  • the inner support disc 219 makes sealing engagement with the shell 203, and also with the inlet fitting 210, to thereby define a drain chamber 220 between the two support discs, as well as the shell chamber 222 below the inner support disc 219.
  • a rotor 223 is mounted in the chamber 222 in the same manner as in the embodiment shown in FIG. 2, and since the structure is essentially the same, it has not been shown in detail in FIG. 4.
  • a support spring 225 similar to support spring 154 is mounted in the lower end of the shell 203 to abut against the rotor 223 on the upper end and against an outlet fitting 226 formed in the bottom wall 227 of the shell 203.
  • a drain tube 228 makes sealing engagement with the outlet fitting 226 on the lower side of bottom wall 227, and extends along the surface of the shell 203 upwardly toward the engine block 213, where at its upper end 229 it opens into the drain chamber 220.
  • the oil enters the filter assembly through the inlet fitting 210 passes into the rotor 223, and, on discharge through the jets, enters the shell chamber 222 .
  • the oil then flows from the outlet fitting 226 through the drain tube 228, upwardly into the drain chamber 220, where it passes through the apertures 217 and outer support disc 208, to return to the engine through the drain passages 216.
  • a float arm 231 is mounted in the lower portion of the shell chamber 222 and carries a float 232 at the free end. At the other end of float arm 231 is mounted a valve member 234 adapted to make sealing contact against the valve seat 235 carried on air inlet fitting 237. Air is supplied by an inlet tube 239 through a check valve 240, which prevents any possible flow of oil out through the air inlet tube 239.
  • the check valve 240 positively prevents any reverse flow of oil through the air inlet line 239, and when the engine is restarted and the air supply turned on, the air will immediately enter through the inlet fitting 237 until conditions are stabilized in the manner discussed previously.
  • Fig. 5 shows a centrifugal separator which is similar in many respects to that shown in Fig. 1.
  • the centrifugal separator 310 has a lower housing member 311 and an upper housing member 312, the latter fitting into the former as shown at 313 and an O-ring seal 315 being provided to prevent escape of oil.
  • the housing members 311, 312 define a housing chamber 318 having a drain passage 319 which extends through member 311.
  • a rotor 320 which includes a rotor cover 324 and a member 321 providing a base 322 and a hollow shaft 323.
  • the rotor cover 324 has a top wall 325 and a downwardly extending peripheral sidewall 327 which fits over the base 322 with 0-ring seal 331 being provided to prevent leakage of oil from the rotor.
  • the rotor top wall 325 has eight equispaced radially extending depression, two of which are shown at 329.
  • the rotor cover 324 is secured in position by a nut 328 on a screw threaded upper portion of the shaft 323.
  • the rotor 320 is rotatably mounted on a fixed spindle 334 which at its lower end is screwed into a bore 335 in a cylindrical member 336 integral with and upstanding from a bridge extending across the base of the lower housing member 311. At its upper end the spindle 334 is screwthreaded and passes through an opening 337 in the upper housing member 312.
  • a cap nut 338 which is held captive by a circlip 339 in an annular groove at its lower end with a washer 340 interposed.
  • the nut 338 holds the housing members 311, 312 together and the housing member 312 may be removed by simply unscrewing the nut 338 from the spindle 334.
  • a rod 341 may be included in the nut 338.
  • the spindle 334 has a lower journal portion 345 on which is rotatably mounted on a bearing bush 347 fitted in a counterbore 348 in the shaft 323.
  • the bush 347 extends from the counterbore 348 to provide a thrust bearing.
  • the spindle also has an upper journal portion 352 on which is rotatably mounted a flanged bearing bush 354 fitted in the shaft 323.
  • a flanged bearing bush 354 fitted in the shaft 323.
  • the diameter of lower journal portion 345 is slightly greater than the diameter of upper journal portion 352 so that when the rotor 320 is fed with oil under pressure, there is a tendency for the rotor 320 to be lifted so as to reduce friction at the thrust bearing 349.
  • the flange on bush 354 serves to reduce friction if the rotor 320 rises sufficiently to abut the nut 338.
  • the spindle 334 has a bore 359 of uniform diameter therethrough which is in communication with the bore 335 in cylindrical member 336. Oil is supplied under pressure to bore 335 from a radial bore 362 in the bridge member in lower housing member 311.
  • the spindle 334 has a pair of radially opposite ports 363 near its upper end through which oil flows into the circular space 364 between the spindle 334 and the shaft 323. The oil then flows from the space 364 into the rotor 320 via a pair of radially opposite ports 365 in the shaft 323.
  • a deflector cup 367 in the rotor cover 324 directs the oil towards the upper part of the rotor 320 through the spaces (not shown) between depressions 329.
  • a cylindrical perforated metal screen 371 extends coaxially with the shaft 323 and is welded at its upper end to the cup 367 and at its lower end to a conical baffle 373 such that cup 367, screen 371 and baffle 373 form a unit which can be dropped into position on rotor member 321.
  • the baffle 373 extends downwardly and outwardly to fit in an annular groove 374 in the rotor base 322.
  • the pressure of inwardly flowing oil causes oil to pass radially inward through the screen 371, below the baffle 373 and into a pair of vertical passages 376 formed within rotor base 322. At their lower ends these passages 376 terminate in tangentially extending jet orifices 378 which operate to rotate the rotor 320 as in the Fig. 1 embodiment.
  • a regulator housing 395 having a bottom wall 396 and sidewalls 397 defining a chamber 399.
  • the regulator housing 395 constitutes a mounting bracket for the separator 310 which is bolted thereto by bolts (not shown) with a gasket 403 interposed.
  • a drain opening 408 is provided in the regulator housing bottom wall 396 and to this is connected a return line to the engine sump.
  • the housing 395 also includes an air inlet 411 to which is connected an air line. Above the inlet 411 is a reduced diameter threaded bore 412 in which is mounted a tire valve 413 with a projecting stem 414.
  • a similar but inverted valve 415 is mounted in the bore 412 between the inlet 411 and the valve 413 to act as a check valve to ensure that oil does not get into the air line.
  • a float arm 421 carried by a pivot pin 422 and secured in the regulator housing adjacent the valve stem 414.
  • the float arm 421 carries a hollow float 424 and at the other end 426 is arranged to depress the valve stem 414 when the oil in chamber 399 rises above a predetermined level.
  • the pin 422 is carried by a pair of angle brackets 427 screwed to the housing.
  • centrifugal separator shown in Fig. 5 will normally be mounted vertically but a slight inclination is permissible.
  • the use of a fixed spindle has been found to facilitate bearing alignment and thus permit a reliably high rotor speed.
  • Electrical or other level detectors can be used in place of the float if desired. This might be desirable if the air valve needed to be remote from the oil awaiting drainage. In effect the air valve maintains a constant low air pressure in the separator casing and it is a surprising feature of the invention that this air pressure substantially facilitates drainage without materially increasing air entrainment in the oil (which could lead to undesirable foaming in the sump). In effect, drainage generally takes place in the natural way with a vortex; the air pressure used is not normally sufficient to blast the oil out of the casing (except in the Fig. 4 embodiment). In some cases a carefully regulated constant pressure air supply could be directly connected to the separator casing without a float-operated air valve but provision would have to be made to prevent air entering the sump when the engine was stopped and oil was not circulating.

Landscapes

  • Centrifugal Separators (AREA)
  • Lubrication Details And Ventilation Of Internal Combustion Engines (AREA)
  • Cyclones (AREA)
  • Filtration Of Liquid (AREA)
  • Preparation Of Compounds By Using Micro-Organisms (AREA)

Claims (19)

1. Verfahren zum Entfernen von Verunreinigungen aus einer Flüssigkeit durch Zentrifugieren, bei dem die Flüssigkeit in das Innere eines in einem Gehäuse (11, 12, 95) angeordneten Rotors (20) unter Druck eingebracht wird und aus dem Rotor (20) über eine Düsenöffnung (78) austritt, so daß der Rotor (20) unter der Reaktionskraft rotiert, bei dem Luft in das Innere des Gehäuses (11, 12, 95) zugeführt wird, einschließlich einem Zwischenraum unter dem Rotor (20), um die bei dem Abfluß erzeugte Sogwirkung zu belüften, dadurch gekennzeichnet, daß die Luft unter einem Druck über dem Atmosphärendruck zugeführt wird, um den Flüssigkeitsabfluß aus dem unteren Ende des Gehäuses (11, 12, 95) zu unterstützen.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß in dem Gehäuse (11, 12, 95) ein im wesentlichen konstanter Luftdrück aufrechterhalten wird.
3. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß die Luft im wesentlichen nur zugeführt wird, wenn der Pegel der zum Abfluß aus dem Gehäuse (11, 12, 95) bereitstehenden Flüssigkeit über einen vorbestimmten Pegel steigt.
4. Verfahren nach Anspruch 3, dadurch gekennzeichnet, daß die Luft über ein schwimmergesteurtes Ventil (113) zugeführt wird.
5. Verfahren nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß die Flüssigkeit Öl ist.
6. Zentrifugal-Ölreinigungseinrichtung bestehend aus einem Gehäuse, das eine Kammer (18) umgrenzt, einem Rotor (20) in der Kammer (18), Mittel (62, 63, 64, 59, 66) zum Einbringen von zu reinigendem Öl unter Druck in das Innere des Rotors (20), Düsen (78) zum Ausbringen von Öl aus dem Rotor (20) in die Kammer (18), wobei durch die Reaktionskraft der Rotor (20) rotiert, einem Ölauslaß (108) für die Dränage des Öls aus einem Zwischenraum in dem unteren Ende des Gehäuses (11, 12, 95) und einem Ventil (113) zur Zuführung von Luft in das Innere des Gehäuses (11, 12, 95), um so die bei der Dränage erzeugte Sogwirkung zu belüften, gekennzeichnet durch Mittel (111 bis 126), die mit dem Inneren des Gehäuses (11, 12, 95) zum Anschluß an eine Zufuhrstelle von Luft über dem atmosphärischen Druck in Verbindung stehen, wobei diese Mittel (111 bis 126) das Ventil (113) enthalten, welches so angeordnet ist, daß die Luft in das Innere des Gehäuses (11, 12, 95) zugeführt wird, wenn der Pegel des zum Abfluß aus dem unteren Ende des Gehäuses (11, 12, 95) bereitstehenden Öls über einem bestimmten Pegel liegt.
7. Einrichtung nach Anspruch 6, dadurch gekennzeichnet, daß das Ventil (113) ein schwimmerbetätigtes Ventil ist.
8. Anordnung nach Anspruch 7, dadurch gekennzeichnet, daß das schwimmerbetätigte Ventil (113) einen Schwimmer (124) enthält, der an einem beweglich montierten Schwimmerarm befestigt ist.
9. Einrichtung nach Anspruch 8, dadurch gekennzeichnet, daß der Schwimmer (124) in einer zweiten Kammer (99) angeordnet ist, die sich unterhalb der ersten Kammer (18) befindet, und daß der Ölauslaß (108) in der zweiten Kammer (99) vorgesehen ist.
10. Anordung nach Anspruch 8, dadurch gekennzeichnet, daß der Schwimmer in der ersten Kammer (18) angeordnet ist.
11. Zentrifugal-Ölifiltersystem für eine Maschine mit einer Öl unter Druck fördernden Ölpumpe und einem Pumpensumpf, bei dem das Filtersystem ein eine Kammer (18) umgrenzendes Gehäuse (11, 12, 95), eine Dränageleitung zwischen dem unteren Ende des Gehäuses (11, 12, 95) und dem Pumpensumpf, eine Öldruckleitung, die die Ölpumpe und das Gehäuse (11, 12, 95) miteinander verbindet, und einen Rotor (20) in der Kammer (18) enthält, dessen Inneres so ausgebildet und angeordnet ist, daß er mit Öl unter Druck aus der Druckleitung beaufschlagt werden kann, wobei der Rotor (20) Düsenöffnungen (78) für den Austritt von Öl in die Kammer (18) besitzt und der Rotor (20) aufgrund der Reaktionskraft um eine im wesentlichen vertikale Achse rotiert, wobei Einrichtungen (111 bis 126) vorgesehen sind, um Luft in das Innere des Gehäuses (11, 12, 95) zuzuführen, so daß die bei der Dränage auftretende Sogwirkung belüftet wird, dadurch gekennzeichnet, daß das Gehäuse (11, 12, 95) durch die Einrichtungen (111 bis 126) mit einer Druckluftquelle verbunden ist, die Luft über dem Atmosphärendruck liefert, um die mit dem Öl, das dem Pumpensumpf wieder zugeführt wird, mitgeführte Luft zu ersetzen, so daß ein Anstieg des Öls innerhalb der Kammer (18) verhindert wird.
12. Zentrifugal-Ölfiltersystem nach Anspruch . --U, dadurch gekennzeichnet, daß es einen Schwimmer (124), der in Abhängigkeit von dem Ölpegel in dem Gehäuse (11, 12, 95) beweglich ist, und ein Ventil (113) enthält, welches durch den Schwimmer (124) betätigt wird und welches mit der Druckluftquelle verbunden ist.
13. Zentrifugal-Ölfiltersystem nach Anspruch 10, dadurch gekennzeichnet, daß der Schwimmer (124) in der Kammer (18) angeordnet ist.
14. Zentrifugal-Ölfiltersystem nach Anspruch 12, dadurch gekennzeichnet, daß der Schwimmer (124) in einer zweiten Kammer (99) angeordnet ist, die unterhalb der ersten Kammer (18) liegt und daß die Dränageleitung mit der zweiten Kammer (99) verbunden ist.
15. Zentrifugal-Ölfiltersystem nach einem der Ansprüche 11 bis· 14, dadurch gekennzeichnet, daß das schwimmerbetätigte Ventil (113) einen Schwimmerarm (170) enthält und daß der Schwimmer (175) am einen Ende des Schwimmerarmes (170) befestigt ist und daß an dem Schwimmerarm (170) ein Ventilglied (180) befestigt ist.
16. Zentrifugal-Ölfiltersystem nach Anspruch 15, dadurch gekennzeichnet, daß das Ventilglied (180) mit einem Ventilsitz (178) an dem Gehäuse (141) zusammenarbeitet und daß der Ventilsitz (178) von einem der Druckluftquelle verbundenem Fitting (177) getragen wird.
17. Zentrifugal-Ölfiltersystem nach Anspruch 16, dadurch gekennzeichnet, daß der Schwimmerarm (170) flexibel ist und daß das endere Ende des Schwimmerarmes an dem Gehäuse (141) befestigt ist.
18. Zentrifugal-Ölfiltersystem nach einem der Ansprüche 11 bis 17, dadurch gekennzeichnet, daß Befestigungsmittel (150) zur Befestigung des Gehäuses an der Maschine vorgesehen sind, welche ein Schraubfassungselement (149) enthalten, das die Befestigungsmittel (150) und das Gehäuse (141) miteinander verbindet und daß die Öldruckleitung durch das Fassungselement (149) verläuft.
19. Zentrifugal-Ölfiltersystem nach Anspruch 18, dadurch gekennzeichnet, daß die Befestigungsmittel (213) auch die Dränageleitung (216) enthalten.
EP83900493A 1982-01-19 1983-01-18 Zentrifugalseparator Expired EP0098866B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83900493T ATE20315T1 (de) 1982-01-19 1983-01-18 Zentrifugalseparator.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US34088482A 1982-01-19 1982-01-19
US340884 1982-01-19

Publications (2)

Publication Number Publication Date
EP0098866A1 EP0098866A1 (de) 1984-01-25
EP0098866B1 true EP0098866B1 (de) 1986-06-11

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EP (1) EP0098866B1 (de)
JP (1) JPS58502188A (de)
AT (1) ATE20315T1 (de)
AU (1) AU555683B2 (de)
BR (1) BR8305198A (de)
CA (1) CA1188662A (de)
DD (1) DD228183A5 (de)
DE (2) DE8322870U1 (de)
ES (1) ES8501052A1 (de)
GB (1) GB2113122B (de)
HK (1) HK54786A (de)
IT (1) IT1161851B (de)
PT (1) PT76116A (de)
WO (1) WO1983002406A1 (de)
ZA (1) ZA83314B (de)

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CN102029086A (zh) * 2009-09-30 2011-04-27 奥凯嘉集团有限公司 一种离心式滤清器转子

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GB2160796B (en) * 1984-05-04 1987-09-16 Ae Plc Oil cleaning assemblies for engines
GB8618006D0 (en) * 1986-07-23 1986-08-28 Ae Plc Centrifugal oil filter
FR2725917B1 (fr) * 1994-10-19 1997-11-21 Moatti Filtration Ensemble de traitement d'un fluide par filtration et centrifugation
GB9500571D0 (en) * 1995-01-12 1995-03-01 Glacier Metal Co Ltd Fluid circulation centrifugal cleaner
GB9502055D0 (en) * 1995-02-02 1995-03-22 Glacier Metal Co Ltd Liquid cleaning system including back-flushing filter and centrifugal cleaner therefor
GB2314036B (en) * 1996-06-10 2000-02-02 Fram Europ Centrifugal filter
US6210311B1 (en) * 1998-09-25 2001-04-03 Analytical Engineering, Inc. Turbine driven centrifugal filter
US6579218B1 (en) 1998-09-25 2003-06-17 Analytical Engineering, Inc. Centrifugal filter utilizing a partial vacuum condition to effect reduced air drag on the centrifuge rotor
US6261455B1 (en) 1998-10-21 2001-07-17 Baldwin Filters, Inc. Centrifuge cartridge for removing soot from oil in vehicle engine applications
US6517475B1 (en) 1998-09-25 2003-02-11 Baldwin Filters, Inc. Centrifugal filter for removing soot from engine oil
US6520902B1 (en) 1998-10-21 2003-02-18 Baldwin Filters, Inc. Centrifuge cartridge for removing soot from engine oil
US6428700B1 (en) 2000-09-06 2002-08-06 Baldwin Filters, Inc. Disposable centrifuge cartridge backed up by reusable cartridge casing in a centrifugal filter for removing soot from engine oil
US7393317B2 (en) 2005-04-11 2008-07-01 Cummins Filtration Ip, Inc. Centrifuge rotor-detection oil-shutoff device
DE102008013465A1 (de) * 2008-03-10 2009-09-17 Hengst Gmbh & Co.Kg Schmierölzentrifuge einer Brennkraftmaschine
US20110011795A1 (en) * 2009-07-15 2011-01-20 Hoff William D Fluid pressure driven centrifuge apparatus
RU2511796C1 (ru) * 2012-12-26 2014-04-10 Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Иркутская государственная сельскохозяйственная академия" Центробежный масляный фильтр двигателя внутреннего сгорания
KR101470837B1 (ko) * 2014-04-08 2014-12-10 신흥정공(주) 수분배출구조를 갖는 원심분리기 및 이를 이용한 퓨리파이어 시스템
GB2569167B (en) * 2017-12-08 2020-10-14 Mann & Hummel Gmbh Filter assembly having a valve movable between closed and open configurations

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GB731312A (en) * 1953-03-03 1955-06-08 Glacier Co Ltd Improvements in or relating to centrifugal separators
US2983384A (en) * 1958-05-07 1961-05-09 Charles A Winslow Centrifuging and lubricant-purifying device
GB1089355A (en) * 1965-09-22 1967-11-01 Glacier Co Ltd Centrifugal fluid cleaners
JPS479392U (de) * 1971-02-24 1972-10-04
US4046315A (en) * 1975-10-23 1977-09-06 The Weatherhead Company Centrifugal separator with discharge pump
US4106689A (en) * 1977-04-06 1978-08-15 The Weatherhead Company Disposable centrifugal separator

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Publication number Priority date Publication date Assignee Title
CN102029086A (zh) * 2009-09-30 2011-04-27 奥凯嘉集团有限公司 一种离心式滤清器转子

Also Published As

Publication number Publication date
GB8301240D0 (en) 1983-02-16
DE3363978D1 (en) 1986-07-17
PT76116A (en) 1983-02-01
CA1188662A (en) 1985-06-11
GB2113122A (en) 1983-08-03
HK54786A (en) 1986-08-01
ZA83314B (en) 1984-05-30
JPS58502188A (ja) 1983-12-22
ES519063A0 (es) 1984-11-01
EP0098866A1 (de) 1984-01-25
ES8501052A1 (es) 1984-11-01
IT8319179A0 (it) 1983-01-19
DE8322870U1 (de) 1984-04-05
AU555683B2 (en) 1986-10-02
DD228183A5 (de) 1985-10-09
ATE20315T1 (de) 1986-06-15
WO1983002406A1 (en) 1983-07-21
AU1157383A (en) 1983-07-28
GB2113122B (en) 1985-07-17
IT1161851B (it) 1987-03-18
BR8305198A (pt) 1983-12-27

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