US2835338A - Liquid bath air cleaner - Google Patents

Description

y 1958 w. w. LQWTHER 2,835,338

LIQUID BATH AIR CLEANER Filed Jan. 6, 1955 5 Sheets-Sheet 1 FIG.1

ATTORNEYS May 20, 1958 w. w. LOWTHER LIQUID BATH AIR CLEANER 5 Sheets-Sheet 3 INVENTOR BY WW4 514/223 ATTORNEYS 5 Sheets-Sheet 4 Fl 6. 4

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F l G May 20, 1958 W. W. LOWTHER V LIQUID BATH AIR CLEANER 5 Sheets-Sheet 5 Filed Jan. 6, 1955 PIES 1%, azw /d wwf ATTORNEYS United States Patent LIQUID BATH AIR CLEANER Wilfred W. Lowther, Chicago, IlL, assignor to United Specialties Company, Chicago, 111., a corporation of Delaware Application January 6, 1955, Serial No. 480,154 6 Claims. (Cl. 183--15) This invention resides in the field of liquid bath air cleaners for use with internal combustion engines, although it is not restricted in this respect.

A primary object of my invention is a new and improved liquid bath air cleaner having a rectangular housing, although many, if not all, of the important features and inventive principles are equally applicable to any configuration of housing.

Another object is a liquid bath air cleaner having a built in after filter beyond the point of liquid pullover during normal operation. 1

Another object is a liquid bath air cleaner of the above type having an after filter which is graded in its filtering intensity.

Another object is a liquid bath air cleaner of the above type having a cup or liquid sump removably attached to its lower end, and having a plurality of filter elements or cartridges that are removable and insertable through the lower end.

Another object is a liquid bath air cleaner of the above type with means in the liquid sump to prevent sloshing and splashing when the unit is jostled or shaken violently, for example when used on a tractor or the like.

Another object is a liquid bath air cleaner with a removable sump constructed so that the housing will not drip when the cup is removed.

Another object is a liquid bath air cleaner having a removable sump cup with means to suspend the cup below the housing a predetermined distance so that the inner mechanism may drip.

Another object is a liquid bath air cleaner having a chamber or zone to which dirt and grit will settle and remain undisturbed during the normal operation of the unit.

Another object is a liquid bath air cleaner of the above type with means for metering the liquid into the moving air stream.

Another object is a liquidbath air cleaner having removable filter cartridges or elements constructed so that air cannot leak past them.

Another object is an improved type of fastening means between the removable cup and the housing.

Another object is a liquid bath air cleaner with means for metering the liquid into the moving air stream constructed so that counterfiow of liquid and air will not take place through the metering means.

Another object is a liquid bath air cleaner having a removable cup constructed so that it can be more easily re placed and removed.

Another object is a liquid bath. air cleaner constructed so that liquid will be more evenly and uniformly dispersed, distributed, or sprayed in the air stream.

Another object is a liquid bath air cleaner with a removable sump or cup constructed so that the unit can rest on any flush surface in a stable position.

Another object is a liquid bath air cleaner of the above type in which the inner cup can bechanged to a. larger 2,835,338 Patented May 20, 1958 or smaller liquid capacity to give a different capacity air cleaner for different uses.

Another object is a liquid bath air cleaner of the above type with a plurality of removable filter elements and sealing means to effect a three-way seal between one or more of the filter elements, outer housing, and the center tube so that all air will flow through the last filter.

Another object is a cleaner of the above type with a plurality of removable filter elements all removably held by a central unitary thrust mechanism.

Other objects will appear from time to time in the ensuing specification and drawings in which:

Fig. 1 is a plan view of my air cleaner;

Fig. 2 is a section taken along line 2--2. of Fig. 1;-

Fig. 3 is a section taken along line 33 of Fig. 1;

Fig. 4 is a partial side view, on an enlarged scale, of the cup attaching means;

Fig. 5 is an enlarged detail, in section, of the after filter detent shown in Fig. 2;

Fig. 6 is an enlarged detail, in section, of the after filter seal shown in Fig. 3;

Fig. 7 is an enlarged plan view of a part of the toothed bafile ring;

Fig. 8 is a side view of a wing nut half;

Fig. 9 is a top view of a full wing nut;

Fig. 10 is a bottom view of a full wing nut;

Fig. 11 is a section taken along line 11-11 of Fig. 12; and

Fig. 12 is a side view, partly in section, of the cup attaching means in its inoperative position.

The unit includes a housing H enclosing a filter medium F disposed in an air passage which includes an inlet I and an outlet 0 with a cup C on the lower end of the housing. While I have shown a rectangular housing, it should be understood that many of the principles, purposes and inventive concepts can be applied equally well to the conventional circular housing, a hat-type air cleaner, or various other forms, and therefore the rectangular unit selected for disclosure should not be interpreted in a restricted sense.

The inlet I is formed from a generally upright center tube 10 which terminates at 12 in Fig. 3. The housing H is closed on top by a top cap 14, which is suitably welded or otherwise secured to the housing and to the inlet and outlet. i

The filter medium F includes a plurality of filter elements which are positioned in the housing, each having a generally rectangular exterior with a central opening for the inlet tube. All of these elements are removable and insertable through the end of the housing which is closed by the removable cup C. The top element 16 is an after cleaner or filter having an inner body 18 and an outer body 20 connected along their lower edge by a spider element 22 in Fig. 5. The lower inner and outer edges are formed into flanges at 24 and 26 which carry gaskets 28 and 30. Each of the gaskets is formed as a continuous piece splice-molded under heat and pressure, and are U-shaped in cross section so as to surround the flange on the after filter body. Each gasket has openings as at 32 in each leg of the U section so that the gasket will have the sponge efiect normally attributed to sponge rubber, without its accompanying leakage. A retaining ring 34 is welded or otherwise suitably secured to the center tube to engage the inner gasket while the outer gasket engages a flanged edge 36 formed on the housing H. The filter is provided with upper and lower screens 38 and 40 which can be expanded metal or wire or any suitable screen medium, which retain the filtering medium in the housing. The filtering medium used can be curled cattle tail hair, or any suitable material. Generally the filtering medium of this after filter should be an animal hair or felt which has a relatively fine screening intensity.

3 I find it advantageous to provide several layers of difierent filtering mediums in the after filter to acquire a graduated filtering intensity which becomes denser in the direction of air ilow. This type of graded or graduated pack remarkably improves the pullover characteristics or air capacity of the unit.

A main filter element 42 is positioned below the after filter 16 and includes inner and outer body members 44 and 46 interconnected at their ends by upper and lower spider members 48 and 50 with suitable expanded wire screens 52 and 54 or the like to retain the filter medium. The upper edge of the inner and outer body members are rolled over or beaded, as at 56 and 58, to engage the gaskets on the after filter to form an airtight joint. The filter medium in the main element can be coiled copper wire, springs, or the like, or any suitable relatively coarse filtering material which is capable of being spread rather evenly throughout the element. The inner housing 44 of the main filter element has a lower tubular extension 60 with a reduced cross section for reasons to be set forth hereinbelow.

It should be noted, for example in Figures 2 and 3, that there is a limited clearance between the outer housing and the insertable cartridges or filter elements, such clearance being designated at A. The same is true on the inside, a limited clearance existing between the center tube and the cartridges, such as at B. The purpose is for ease of assembly, meaning that parts are all preferably made from metal stampings which is not highly accurate work. Accordingly tolerances are not close. Limited clearance, as at A and B, is provided so that variations in dimensions of the parts will not prevent proper assembly.

A scrubber or coarse filter element 62 positioned below the main element is formed with an inner housing or tube 64 and an outer body 66 with upper and lower spiders 68 and 70 and upper and lower screens 72 and 74 of the expanded wire type or any other suitable variety. The upper edges of the body members are rolled over or beaded, as at 76 and 78, to evenly engage the bottom of the main filter element. The inner housing or tube 64 is also provided with a lower tubular extension 80.

The lower edge of the housing is provided with a gasket retainer 82 in the form of a channel as a seat for a suitable gasket 84 opened downwardly. The upper edge 86 of the liquid cup C is rolled or headed to engage the gasket. The lower edges or sides of the cup are beveled or slanted inwardly along the-longitudinal sides as at 88 for reasons to be set forth hereinbelow.

The main cup C carries an inner cup 90 which is welded or otherwise suitably secured to a splash battle 92. The battle is formed with a central opening 94 having a plurality of radial fingers 96 which project inwardly from the edge of the cup, for reasons to be set forth hereinbelow. The splash baffle extends outwardly to a ridge 98 indicating the normal liquid level and is rolled on its outer edge 100toclosely approach the outer cup. The bottom of the outer cup is indented, as at 102, so that the inner cup will be raised or spaced slightly from it. The splash baffle has a plurality of openings 103 for means to be set forth hereinbelow.

A metering baffie or central band 104 is mounted on the; splash bafile and projects upwardly approaching the scrubber element. It is secured by welding or otherwise to the splash baffle by a collection of feet or tabs 106 which space this bathe from the splash bafile a predetermined distance to provide a metering slot or opening 108. The control band or baffie 104 also has a plurality of leak air holes 110 for reasons to be set forth hereinbelow. A plurality of spring clips 112, or the like, are welded, riveted or otherwise suitably secured to the control band or baffle to, engage the lower end of the scrubber element.

The filter elements are all removably mounted in the housing by the following mechanism: The after filter 16 carries a ball latch 114 with a, springbiased detent 115 as shown in Figs. 2 and 5 which snaps over the retainer ring 34. The after filter is pushed up through the bottom end of the housing until the ball latch snaps over this ring. The spring is strong enough to hold the after filter in position. To remove the after filter, a plurality of handle-type elements 116 are provided which can be grasped by the user.

The center tube 10 carries a cross bracket 118 at its lower end with a longitudinal stud 120 threaded at 122 and reduced in diameter at 124 with a threaded end 126. A bracket 123 mounted on the extension 60 from the main element has an internally threaded adapter which screws onto the threaded portion 122 of the stud. The adapter can be rotated by a suitable wing nut 132 or the like. The scrubber element 62 carries a bracket 134 with a similar internally threaded adapter 136 actuated by a wing-nut 138 or the like and is attached to the lower threaded portion 126 of the stud. It should be noted that the extension 80 on the scrubber element, forming an extension of the center tube, extends down to the normal liquid level 98 in the cup. The extension 60 on the main element is reduced in cross section so that it telescopes inside of the scrubber element.

The center tube carries a downwardly extending vent tube 140 which curves outwardly through a suitable opening 142 for removing vapor from the crank case of the engine to which it is attached.

The removable cup is attached to the bottom end of the housing by several attaching mechanisms 144 each of which includes upper and lower brackets 146 and 148 mounted on the housing and cup respectively. A machine bolt 150 or the like having a head 151 is fitted into the open interior of the upper bracket andis held by the inwardly turned tabs 152 shown in Fig. ll which define a front opening 154 on the outside of the bracket. These tabs are stepped at 156 in Fig. 12 to provide an abutment. The lower bracket on the cup is similar to the upper brackets and has the central opening 154 so that the bolt 150 can be pivoted into it about its head 151. Each bolt carries a wing nut 158 and a suitable washer 160 to draw the cup up tightly against the gasket struc ture 84 on the housing.

When the bolts are swung to an outward position, the lower surface of the corner of the head 151 will engage the abutment 156 formed by the notched flat construction at the same time that its rear edge engages the inside of the bracket. Thus the bolt will be held in an outward position as shown in Fig. 12. When the cup with a suitable liquid is being mounted on the housing, the bolts and wing nuts will not get in the way of the operator and hinder proper mounting of the cup. When the cup is seated on the housing, the wing nuts and bolts can be flipped inwardly by the operator so that they will pivot through the opening in the face of the lower brackets. The wing nuts can then be turned upward until the cup is firmly seated.

Each attaching bolt and bracket mechanism is provided with a wire bail 162, in Figs. 2 and 4, the upper ends of which are turned in and project through openings 164 in the upper bracket to give the bail a pivotal mounting. The bail flares outwardly into a loop at its lower ends around the lower bracket 148 on the cup and around the wing nut and is bent inwardly at 166to conform generally to the longitudinally depressed or slanted edge of the cup. It should be noted that the crosspiece or bottom of the bracket is a substantial distance below the bracket on the cup as shown in Fig. 4, for reasons to be set forth hereinbelow.

In Fig. 1 the housing carries a suitable mounting plate 168 with fixed mounting brackets 170 on each side to secure the air cleaner to any suitable structure, such as the frame of a tractor or vehicle.

The wing nuts 158 on the bolts for mounting the cup on the lower end of the housing are formed from two plates 172, with grooves or channels 174. Two such plates are positioned back to back to form a central opening or bore 175 and spot-welded or otherwise suitably secured together at 176. Thus, wing portions 178 extend from each side. The upper portion of the bore is suitably threaded at 180, while the lower portion 182 is enlarged to form a housing for a burred or upset end 184 on the end of the bolt 150. By securing the plates back to back in this manner, slight grooves or channels 186 are formed between the sides of the plate and the bolts so that any dirt, grit and dust can clear itself from the assembly. I

The use, operation and function of my invention are as follows:

I have disclosed and described a rectangular cleaner although the inventive principle in many respects is equally applicable to other cleaner configurations. How ever, a rectangular cleaner has advantages over round or hat type cleaners in that it can be fitted into areas with more limited dimensions while having the same capacity.

Generally I provide a cleaner housing with an air path having an inlet and outlet with a plurality of filter elements disposed in the path. The housing has a removable cup closing its lower end, and all of the filter elements in cartridge form are removable and replaceable through the open end of the housing when the cup has been removed. I have shown three such elements, a scrubber element, a main element, and an after filter element. It should be noted that these filter elements, although for some purposes more or less could be used, can only be inserted in a predetermined order. Further more, it is impossible to insert the elements upside-down. The after filter 16 can only be inserted with the flanged edge last so that the ball latch can snap over the retaining ring on the center tube. If the after filter were upside-down, the wing nuts and retaining studs for the main element and scrubber would not engage. The same is true of the main element and scrubber. sions 60 and 64 prevent them from being inserted incorrectly. It should be noted that these extensions, in eltect, form continuations of the center tube and by the locking means shown in Fig. 2, all of the filter elements can be quickly and easily removed in order after the cup has been removed.

The liquid capacity of the cup is such in relation to the air capacity of the cleaner and the air, liquid and filtering intensity of the filter elements that during normal operation, the majority of the liquid from the inner cup is retained by the scrubber element. Only a small part of the main element receives any of the liquid. The capacity of the unit is such that during normal operation none of the liquid will be pulled over into the after filter. Therefore, the after filter performs a dry cleaning function.

The scrubber is composed of a relatively coarse ma terial. The same is true of the main element. But the after filter is composed of animal hair or felt or the like and performs a relatively fine filtering action. The after filter can be graded with layers of filtering material having diiferent filtering intensity, increasing upwardly. The scrubber can also be graded running from coarse to medium and fine in the direction of air fiow.

Air descends, or is drawn, vertically down through the center tube to the bottom of the center or inner cup where it reverses and flows upwardly around and between the teeth or fingers 96 formed on the splash bafiie. The air picks up liquid from the inner cup and conveys it in a spray form to the scrubber. The fingers project radially inwardly and tend to direct the liquid to the inside of the filter scrubber. Currents of air in the nature-of eddy currents are created above each finger, which give an atomizing or a better mixing of the liquid with the air. I have found that the fingers can be bent up slightly to produce a nozzle effect. In effect, each The extenfinger acts as a feeder or functions as a control factor by finely spraying the liquid into the moving air stream. Furthermore, the control baizle directs the mixture of air and liquid to the inside area of the scrubber. Thus the main air flow carrying the oil or liquid rises into the scrubber in a limited area confined to the region lying within the control band or bafiie. This area is generally labeled X in Fig. 2.

The scrubber element overlies or hangs the control baflie so that liquid with dirt can descend by gravity to thearea designated Y in Fig. 2 outside the control battle. The liquid in this zone can only return to the air path in the zone X through the metering opening 108. This metering orifice is specifically chosen in size to limit the amount of fluid that can return to the air path and at a definite rate. In fact, the fluid will stand in a head he hind the control bafile in the zone Y as it is metered under the baflle returning to the zone X. Thus the standing head of dirty fluid in zone Y will allowthe dirt to descend, or settle out by gravity, through the openings 103 in the splash bafile into the lower reservoir or zone Z in Fig. 2. The zone Y is, in essence, a quiescent area which receives a return gravity fiow of liquid from the scrubber. From the zone Y the liquid. is metered inwardly through the orifice 108 into the air stream.

Thus, a definite circulation ofcleaning liquid is established, starting with the cleaning liquid being lifted from the teeth or fingers on the battle and carried in droplet or aspirated form into the scrubber where it flows or moves outwardly to return to the zone Y by gravity to be metered through the opening 108 onto the fingers again for recirculation. The liquid standing in the zone Y will allow the dirt and grit to settle out through the openings in the splash baflle to the lower sump Z where it cannot return to the circulating fluid. For proper operation the normal liquid level should be approximately A above the fingers 96.

The splash bafiie extends outwardly and terminates directly adjacent'the wall of the cup so that no splashing or sloshing of liquid will occur as the unit is being bounced or jarred during heavy duty operation.

It is impossible for air to leak by the filter elements on its way to the outlet because the after filter and main elements are tightly sealed by the gasket structure. If any leakage occurs, it can only result. in a bypass of air around the scrubber, however air must always flow through the main element. Under many conditions of operation, air will leak around the scrubber, and it should be noted that this air must also leak by the control baffle 104. One possible passage would be through the metering orifice or slot 108, however this is undesirable as it would hinder the return metered flow of liquid from the quiescent zone Y to the air stream. Therefore, I provide a suitable number of leak holes 110 of suitable size in the control band or baflie so that the leak air can pass the control bafiie without disturbing the head of liquid standing behind it in the zone Y.

By shaping the longitudinal sides of the cup inwardly to form beveled edges as at 88 running longitudinally along the cup, I provide clearance for the wing nuts. It is therefore possible to position the Wing nuts above the bottom of the liquid sump. This is particularly act-- vantageous as the air cleaner can be more easily packaged and will rest flush on a pallet or carton on the fiat bottom of the cup rather than directly on the wing nuts. Furthermore, the air cleaner, after it has been removed from a vehicle, may be set down on the bottom of the cup without the danger of a heavy impact. on the lower end of the wing nuts, which would cause damage to the aircleaner by bending the supporting brackets.

The upper brackets 146 are formed with notches or abutments so that the bolt can be held at an angle while the cup is being replaced. This is particularly desirable as the Weight of the cup with the cleaning fluid in it is substantial, and if the bolts dangle directly downwardly,

7 they will severely hamper and interfere with the proper mounting of the cup. In the position shown in Fig. 12 the bolts can be easily knocked off of the abutment by the user after the cup is in position and the bolts will fall or pivot into the slotted lower bracket.

The specific wing nut construction is also highly desirable asit allows grit and dust which accumulates under service conditions to work its way out of the threads without permanently injuring the nutsin any way. Furthermore the solid skirt of the nut between the wing elements or lobes prevents the user from marring or ruining the threads on the bolts by grasping the nuts between the wings with a wrench or pliers.

Some of the important features of my invention are as follows:

All of theair drawn through the unit must flow through the after filter due to the sealing arrangement in Fig. 6. It should be noted that these cellular type gaskets form a three-way seal at the after filter, namely between the after filter and the outer housing, between the after filter and the inner housing, and between the after filter and the main element.

The inner cup 90 is spot welded or otherwise suitably secured to the splash bafile, audit should be noted that the cup 90 can be changed and a larger or smaller cup connected to the splash baffle so that the liquid capacity unit is changed as governed by the intended use of the device. Changing the size of the cup 90 does not vary the quantity of liquid in the sump but it does vary the quantity of liquid exposed to the air stream.

It is important to note that all of the air in the stream passes through the main element while the scrubber has a two way flow, the air rising in the inner zone and the oil returning to the quiescent zone Y from the outer portion of the scrubber.

The inner ring 34 on the center tube in Fig. 6 is slightly above the outer flange 36. Thus when the main filter element is pushed up in the housing and secured in place by the center stud and wing nut 132, it forces the gasket into contact with the outer flange 36 first and the central thrust from the wing nut and the center stud forces the gasket 28 into engagement with the center ring 34. By this arrangement a tight seal is assured between the outer edge of the main filter element, the outer gasket 34), and the flange 36 on the outer housing. Thus this structure provides a single operative means for sealing bottom inner and outer gaskets, this means being located in the center of the housing to provide a central upward thrust;

The stepped center stud also allows the scrubber to be removedwithout-disturbing'the main filter element in any way. Thrust seal of the gasket 23, and 30 is, not distinguished wherrthe' scrubber is being removed and replaced.

It should-also benotcd that the end of the stepped studis above the lower edge, of the main housing H. When the cup and filter elements have been removed, the housing can be placed on a flat surface and the center stud will not touch the surface, thus eliminating any broken. parts during manufacture or. otherwise.

The inner cup'and splash bafiie allow liquid to fill the sump zone Z, and during rough handling the spring element 112 prevent the inner cup from, bouncing. The raised ribs 102 in the bottom of. the outer cup prevent the formation of a vacuum betweenthe inner andouter cup, although these ribs could be formed in the inner cup as well.

The rectangular configuration: of the housing facilitates the mounting of the unit by the brackets in Fig. 1 as compared to a circular housing or hat type cleaner.

While I have shown and described a preferred form of my invention, it should be understood that many modifications, changes, substitutions and alterations can be Inadewithout departing fromthei fundamental theme.

I therefore, wish. that my invention be unrestricted except as by the. appended claims.

I claim:

1'. In a liquid bath air cleaner, a generally upright housing having an air path with a dirty air inlet and a clean air outlet, a filter element in the air path in the housing, a liquid sump cup removably attached to the lower end of the housing to provide a liquid sump and having a normal liquid level, a seat on the housing for the cup, manually operable attaching means for detachably connecting the sump cup to the housing in engagement with the seat, a bail-type mechanism associated withthe sump cup and housing for supporting the cup in substantial spaced relation to the housing out of engagement with the seat, means on the cup to engage the said bail-type mechanism when the manually operable attaching means is detached so that the sump cup will be held in said substantial spaced relation to. the housing, such bail-type mechanism being pivoted to the housing and movable between operative and inoperative positions and constructed so that when the attaching means is detached and the bail-type mechanism is in its operative position, it will support the cup in said substantial spaced relation to the housing so that liquid from the filter element and housing may drain back into the cup, but when the bailtype mechanism is in its inoperative position the sump cup may be completely detached and removed from the housing.

2. in a liquid bath air cleaner, a generally upright housing defining an air passage with an air inlet for dirty air and an outlet for clean air, the lower end of the housing being generally open, a removable cup attached to and closing the lower end of the housing, a liquid sump reservoir in the cup in communication with the air passage, a plurality of filter mediums rcmovably mounted in the housing so as to be all removable through the open lower end when the cup is removed, each such filter medium effecting a limited clearance with the housing airpath, totally confined in the housing, and positioned after the main filter medium with respect to the air flow path, coacting means on the housing and main and dry after-filter mediums constructed so that the mediums canonly be assembled in a predetermined order with the dry after-filter medium first and a predetermined side of the dry after-filter medium always up for complete assembly,

and sealing means effecting a seal between the housing;

and main filter medium, between the housing and the dry after-filter medium and between the main and dry afterfilter mediums to prevent liquid from bypassing the main filter medium throughits limited clearance with the housing so that all air flowing through the housing must flow through both the main and dry after-filter mediums at all times during complete assembly.

3. The structure of claim 2 in which the sealing means includes at least one. unitary gasket mounted wholly on the dry after-filter medium so as to be removable therewith for inspection and repair.

4. The structure of claim 2 further characterized by and including detent means for releasably holding the dry after-filter medium in the housing when the main filter medium has been removed.

5. The structure of claim 2 in which the housing is rectangular and includes a center tube inlet for dirty air; 6. The structure of claim 2 further characterized in.

that the main filter medium includes a lower removable scrubber element and an upper removable main element.

(References on following page) References Cited in the file of this patent UNITED STATES PATENTS Darnell Sept. 17, 1940 Wilson Dec. 29, 1931 Hinkle Mar. 29, 1932 Kellogg July 25, 1933 Cartwell Sept. 12, 1933 Lowther Oct. 23, 1945 Sebok Jan. 29, 1946 Bennett Apr. 2, 1946 10 Wistor Oct. 9, 1951 Roerig Nov. 27, 1951 Brixius May 13, 1952 Beach Feb. 10, 1953 Hutchinson et al Aug. 24, 1954 Dreznes Nov. 13, 1956 FOREIGN PATENTS Canada Nov. 29, 1949 France Feb. 2, 1938 France Nov. 1, 1950

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