Title:
MACHINE FOR EXTRACTING DIRT FROM HOLES
United States Patent 3651621
Abstract:
A portable machine used to raise dirt, rocks, and the like from holes, such as fence post and utility pole holes and similar purposes. Means is provided in a closed chamber to extract the heavy and the light dirt particles by gravity separation and then to extract the fine particles by cloth bag filtration. Means is provided to clean the fiber cloths by mechanical vibration. A blower draws a vacuum through the chamber and then through a hose which is lowered into the hole being cleaned.
US Patent References:
Street sweeper
Myer - September 1924 - 1507243
Rotor for compressing machines such as centrifugal blowers and pumps
Buchi - September 1953 - 2652191
Apparatus for filtering solids from gases
Martinez - September 1957 - 2805732
Dust collector
Bunnell - February 1958 - 2823762
Rotors of centrifugal fans
Wood - September 1966 - 3272429
Street sweeper
Myer - September 1924 - 1507243
Rotor for compressing machines such as centrifugal blowers and pumps
Buchi - September 1953 - 2652191
Apparatus for filtering solids from gases
Martinez - September 1957 - 2805732
Dust collector
Bunnell - February 1958 - 2823762
Rotors of centrifugal fans
Wood - September 1966 - 3272429
Application Number:
04/877292
Publication Date:
03/28/1972
Filing Date:
11/17/1969
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
415/206, 55/319, 55/341.200, 55/341.100, 416/186R, 15/340.100
International Classes:
A47L7/00; B01D46/04
Field of Search:
55/319,300,304,305,323,325,341 15/340,347 415/206 416/186
US Patent References:
Primary Examiner:
Nozick, Bernard
Claims:
What is claimed is
1. Apparatus for extracting dirt comprising a chassis, a housing mounted on said chassis, a transverse, vertical bulkhead in said housing dividing the interior of said housing into first and second compartments, first means forming an inlet into said first compartment for connection with a flexible intake hose opening into said first compartment adjacent the top thereof, a horizontal apertured bottom wall disposed substantially midway of the height of said second compartment dividing said second compartment into a lower housing section and an upper housing filter section, said wall having first flanges surrounding the apertures, filter mounting means in said filter section mounting a plurality of sleeve-type cloth filters, said mounting means comprising a top plate having annular flanges extending downwardly in said top plate receiving ends of said sleeves, respectively, a vibrator mounted on the top plate for vibrating said top plate to discharge dirt on said filters to the bottom of said second compartment, a vertical box mounted in said first compartment mounted to said bulkhead having an inlet at the top of said first compartment and an outlet opening into said lower housing section of said second compartment below said wall, baffles positioned in said first compartment and in said lower housing section to direct air in a tortuous path from said first means to said filter housing section, a fan mounted on said second compartment communicating with the filter section for evacuating air through said filter sleeves from the bottom, front portion of said filter housing section, each said compartment being formed with a floor which slants from the middle of said compartment outwardly-downwardly toward either side toward the sides of said body, and access doors for access to each of said compartments hinged to said sides about hinges having horizontal longitudinal axes for discharge of dirt, the lower edges of said doors coinciding with the outer ends of said slanted floors.
2. Apparatus according to claim 1 in which said fan comprises a casing which is scroll shaped in front elevation and has a central front opening, a drive member supported by said casing, a pair of annular disks on said drive member spaced apart and parallel to each other, the central holes of said disks in registry with said front opening, and a plurality of airfoil cross section shaped blades between said disks, each blade having a leading edge curved outwardly forwardly to a maximum chordal width about one-fourth of the radial length of the blade and a substantially radial trailing edge.
1. Apparatus for extracting dirt comprising a chassis, a housing mounted on said chassis, a transverse, vertical bulkhead in said housing dividing the interior of said housing into first and second compartments, first means forming an inlet into said first compartment for connection with a flexible intake hose opening into said first compartment adjacent the top thereof, a horizontal apertured bottom wall disposed substantially midway of the height of said second compartment dividing said second compartment into a lower housing section and an upper housing filter section, said wall having first flanges surrounding the apertures, filter mounting means in said filter section mounting a plurality of sleeve-type cloth filters, said mounting means comprising a top plate having annular flanges extending downwardly in said top plate receiving ends of said sleeves, respectively, a vibrator mounted on the top plate for vibrating said top plate to discharge dirt on said filters to the bottom of said second compartment, a vertical box mounted in said first compartment mounted to said bulkhead having an inlet at the top of said first compartment and an outlet opening into said lower housing section of said second compartment below said wall, baffles positioned in said first compartment and in said lower housing section to direct air in a tortuous path from said first means to said filter housing section, a fan mounted on said second compartment communicating with the filter section for evacuating air through said filter sleeves from the bottom, front portion of said filter housing section, each said compartment being formed with a floor which slants from the middle of said compartment outwardly-downwardly toward either side toward the sides of said body, and access doors for access to each of said compartments hinged to said sides about hinges having horizontal longitudinal axes for discharge of dirt, the lower edges of said doors coinciding with the outer ends of said slanted floors.
2. Apparatus according to claim 1 in which said fan comprises a casing which is scroll shaped in front elevation and has a central front opening, a drive member supported by said casing, a pair of annular disks on said drive member spaced apart and parallel to each other, the central holes of said disks in registry with said front opening, and a plurality of airfoil cross section shaped blades between said disks, each blade having a leading edge curved outwardly forwardly to a maximum chordal width about one-fourth of the radial length of the blade and a substantially radial trailing edge.
Description:
This invention relates to a new and improved machine for extracting dirt from holes. More particularly, the invention relates to a truck or trailer-mounted apparatus having a compartmented body for collection of dirt and rocks drawn through the hose from the bottom of a hole by means of a vacuum fan. Heavy and medium size dirt particles are separated from the air stream in the several compartments and finally the air is drawn through fabric filters to remove the remaining dust. The filters are preferably vibrated so as to be, for practical purposes, self-cleaning.
A principal object of the present invention is to draw dirt, rocks and the like out of holes which have been dug in the ground by other equipment. Earth augers of various types have been used for many years to dig holes for posts, utility poles, building foundation piles and the like. There is a tendency for dirt to drop into the holes when the auger is removed or sometime thereafter. Cleaning out the hole has been a difficult, labor-consuming operation. The present machine rapidly sucks the dirt from the hole with very little labor required.
In accordance with the present invention, a hose is lowered into the hole and a powerful vacuum is drawn through the hose to suck out the dirt. The apparatus separates the dirt from the air, greatly reducing discharge of dust into the atmosphere which would otherwise occur and hence eliminating a potential air pollution nuisance.
Another feature of the invention is the fact that the very heavy and the medium pieces of dirt are separated from the air stream by gravity classification. Hence when the air reaches the bag filters, much of the material which would otherwise tend to clog the filters has been removed and the cloth filters perform their function more effectively. Accordingly, the air is caused to whirl inside the casing so that the particles contact the sides of the casing, and thus are caused to drop from the air stream and fall to the bottom of the compartment where they may be removed at intervals through convenient doors formed in the sides of the body.
Another feature of the invention is the provision of a bank of bag filters which function to remove the fine dirt material and which are of a construction making their installation and removal convenient and rapid.
Another feature of the invention is the fact that the frame on which the bag filters are mounted is subjected either continuously or intermittently to vibration so that material tending to clog the filters is shaken off.
Another feature of the invention is the fact that access to the interior of the body through doors is convenient so that dirt may be removed at intervals when required.
A principal feature of the invention is that the equipment is compact and readily portable so that the apparatus may be moved up to the hole being cleaned even where the terrain is rugged.
Still another feature of the invention is the fact that the fan blade structure is so constructed as to improve the suction.
Other objects of the present invention will become apparent upon reading the following specification and referring to the accompanying drawings in which similar characters of reference represent corresponding parts in each of the several views.
In the drawings:
FIG. 1 is a side elevational view of apparatus in accordance with the present invention partly broken away to reveal internal construction; and
FIGS. 2 and 3 are, respectively, front and rear elevational views likewise broken away in section to reveal internal construction; and
FIG. 4 is a fragmentary, enlarged sectional view of the filter bag mounting and adjacent elements.
FIG. 5 is an enlarged, horizontal, sectional view through the fan;
FIG. 6 is a sectional view substantially along the line 6--6 of FIG. 5;
FIG. 7 is a schematic side elevational view of the vibrating means.
The apparatus hereinafter described in detail is presented in a preferred use for transportation to the site where holes have been excavated. For such purpose the equipment is installed on the chassis 11 of a trailer, truck or other suitable vehicle shown only partly in the accompanying drawings and supported above the ground by means of wheels 12. The body is supported above the chassis 11 by means of a mounting plate 13 which is horizontally disposed and spaced upward from the bottom plate 14. Plates 13, 14 are suitably apertured to provide a well 16 for the wheels 12 on either side. Roof 19 is rectangular. The various outer walls and interior bulkheads of the body are reinforced at intervals by angle bars or other stiffeners so that they do not bend inward when the interior of the body is subjected to vacuum.
Extending longitudinally of the interior of the body is a triangular bottom having an apex 16 which has downwardly outwardly slanted sides 17 each disposed at an angle of about 45 degrees with respect to the horizontal. The space 18 below the slanted sides above the mounting plate 13 provides a compartment for storage of hose and the like, to which access is obtained from the rear. As hereinafter explained, dirt falling off the slanted sides 17 slides outwardly to either side 20 of the body so that access to rear and forward doors 21, 22 on either side permits the accumulated dirt to be cleaned out.
Spaced downwardly from the top and disposed centrally of the rear 23 is the duct 24 which is preferably slanted downwardly rearwardly. Flexible hose 26 is installed over the duct 24, the hose gradually diminishing in diameter as it extends outwardly so that it may conveniently be lowered into the bottom of holes in the earth (not shown).
Front panel 31 is formed with an aperture 32 centrally disposed relative thereto and the casing 33 of the blower is installed in registry with opening 32 to draw air out of the body and discharge the air through opening 36.
Extending transversely of the body approximately midway of its length, is middle bulkhead 41 which divides the body into rear and front compartments 42, 43 respectively. Center bulkhead 41 extends vertically approximately midway of the length of the compartment from side to side. Its bottom is closed off by slanted transverse bottom panels 46a which slope forwardly and rearwardly from a transverse horizontal apex 47a at the bottom of bulkhead 41. Rearward of bulkhead 41 extending vertically at the center of the body is a rectangular box 48 having a square opening 49 at the top through which air enters from rear compartment 42 and having similar opening 51 at the bottom through which air is discharged into front compartment 43. Transverse baffles 46,47 are installed in rear compartment 42 to ensure that air sucked in through duct 24 is caused to swirl within the compartment and to contact the side walls 20, roof 19, rear 23 and intermediate bulkhead 41. The swirling of the dirt causes some of the heavier particles to separate out by centrifugal action and as the particles contact the walls of the compartment they are caused to drop to the bottom and then slide outwardly downwardly along sides 17 where they can be removed through doors 21. Normally the very heavy dirt particles or rocks are separated out in compartment 42 and the remainder is drawn through the opening 51 in bulkhead 41 into compartment 43.
Baffle 52, forward of opening 51 causes air to swirl within compartment 43. Most of the remaining particles of dirt drop out of air stream in box 48 and down into the forward compartment 43 along the slanted bottom 53 of the box 48. Other medium sized particles which swirl around inside the compartment 43 contact the walls thereof and separate out from the air stream, falling onto the outward slanted bottom walls 17 and dropping to adjacent forward side doors 22 where the debris may be removed.
The upper portion of forward compartment 43 comprises a filter chamber 56 which is defined by front 31 and middle bulkhead 41 and filter compartment bottom 57 has a plurality of round holes formed therein and surrounding the holes 58 are upstanding cylindrical flanges 59. The number and spacing of the holes 58 is a matter of choice but preferably they are staggered so that a major portion of the area of bottom 57 is apertured and thus a maximum number of holes 58 is afforded. In a preferred form of the invention, there are 28 holes 58 in a pattern of five staggered longitudinal rows with six holes in the outer and center rows and five holes in the intervening rows. The top mounting plate 61 is located directly above plate 57 having similar holes 62 in alignment with holes 58 and likewise having flanges 63 around the holes. Extending between flanges 59 and 63 are filter bags 64 which are cylindrical sleeves open at the bottom and having closed tops 66. The sleeves 64 are formed of filter cloth to trap remaining dirt in the air stream. The bottom edges of bags 64 fit around the flanges 69 and are held in place by clamps 67. The tops 66 are spaced below the top edges of the bags 64 leaving an open cylindrical portion which fits around flanges 63 and held in place by hands 68.
The top mounting plate 61 is suspended from roof 19 by means of springs 71 and a vibrating mechanism 72 is attached between roof 19 and plate 61. Actuation of the vibrator 72 either continuously or intermittently shakes the bags 64 causing dirt trapped therein to fall down to the bottom of compartment 43 and thus reducing the tendency of the filter bags to clog. When it is necessary to remove the bags 64 for replacement or more thorough cleaning, the bands 67-68 are removed and bags 64 are easily displaced.
A satisfactory vibrator 72 is shown more or less schematically in FIG. 7, it being understood that a variety of suitable vibrators is commercially available. Upper shaft is rotatably mounted on roof 19 by means of pillow blocks 74. Lower shaft 76 is mounted on plate 61 by pillow blocks 77. Sprockets 77,78 are fixed to shafts 73,76, respectively, and interconnected by continuous roller-type chain 79. One of the links of chain 79 carries a heavy weight 81, which dynamically unbalances the system. One of the shafts, such as shaft 76, is turned by motor 82 through any convenient means. Weight 81 causes severe vibration as chain 79 passes around its course.
Air in the filter compartment 56 is discharged through opening 32 in the forward wall 31 directly into blower 34 and thence through opening 36 into the atmosphere.
A preferred blower is shown in FIGS. 5 and 6. Forward and rear annular disks 86,87 are supported by drive member 88 on front 89 of casing 33. Casing 33 is of scroll shape, gradually increasing in radius in the counterclockwise direction of rotation of FIG. 6 and opens into discharge duct 36. The central holes 91 of disks 86,87 register with opening 32 in front panel 31.
Extending between parallel sides 86,87 are blades 91 here shown as seven in number and each generally shaped as an air foil. Each blade has a leading edge 92 which is curved outwardly forwardly to a maximum chordal width indicated by reference numeral 93 about one-fourth the radial length of the blade. The trailing edge 94 is substantially radial. The effect of the air foil shape is that the velocity of air movement is greater on the leading surface of the blade than on the trailing surface and this tends to pull air out from the center hole 32 more effectively than in blades of this general type.
In use of the device, the apparatus is transported to the site and the hose 26 inserted into the bottom of one of the holes in the earth. Fan 23 draws air out of the filter compartment 56, forward compartment 43, box 48, and rear compartment 42 thus pulling air up through the duct 24. Such air contains dirt, rocks and other debris which may have fallen into the hole. Baffles 46,47 cause the air to whirl in the rear compartment 42 and gravity, centrifugal force, and the friction of the particles along the walls of the compartment cause the heavy particles to drop out of the air stream to the bottom where they are periodically removed through rear side doors 21. The middle sized and fine particles escape through the opening 49 into the box 48 and thence into the forward compartment 43. Additional dirt falls out of the air stream into box 48 and compartment 43. The remaining dirt is drawn through the opening 58 in the bottom 57 of the filter compartment 56 and the air is sucked through the filter sleeves 64, causing the fine particles to remain on the inside of the filter bags. The air then flows out through opening 32 through the blower 33 into the atmosphere. The vibrators 72 cause the top plate 61 to vibrate and such operation is conducted either intermittently or continuously. The dirt in the pores of the bag 64 falls down through the openings in bottom plate 57 to the bottom of compartment 43. Thus, all the remaining material in the air stream after the air leaves compartment 42 is discharged through doors 22.
A principal object of the present invention is to draw dirt, rocks and the like out of holes which have been dug in the ground by other equipment. Earth augers of various types have been used for many years to dig holes for posts, utility poles, building foundation piles and the like. There is a tendency for dirt to drop into the holes when the auger is removed or sometime thereafter. Cleaning out the hole has been a difficult, labor-consuming operation. The present machine rapidly sucks the dirt from the hole with very little labor required.
In accordance with the present invention, a hose is lowered into the hole and a powerful vacuum is drawn through the hose to suck out the dirt. The apparatus separates the dirt from the air, greatly reducing discharge of dust into the atmosphere which would otherwise occur and hence eliminating a potential air pollution nuisance.
Another feature of the invention is the fact that the very heavy and the medium pieces of dirt are separated from the air stream by gravity classification. Hence when the air reaches the bag filters, much of the material which would otherwise tend to clog the filters has been removed and the cloth filters perform their function more effectively. Accordingly, the air is caused to whirl inside the casing so that the particles contact the sides of the casing, and thus are caused to drop from the air stream and fall to the bottom of the compartment where they may be removed at intervals through convenient doors formed in the sides of the body.
Another feature of the invention is the provision of a bank of bag filters which function to remove the fine dirt material and which are of a construction making their installation and removal convenient and rapid.
Another feature of the invention is the fact that the frame on which the bag filters are mounted is subjected either continuously or intermittently to vibration so that material tending to clog the filters is shaken off.
Another feature of the invention is the fact that access to the interior of the body through doors is convenient so that dirt may be removed at intervals when required.
A principal feature of the invention is that the equipment is compact and readily portable so that the apparatus may be moved up to the hole being cleaned even where the terrain is rugged.
Still another feature of the invention is the fact that the fan blade structure is so constructed as to improve the suction.
Other objects of the present invention will become apparent upon reading the following specification and referring to the accompanying drawings in which similar characters of reference represent corresponding parts in each of the several views.
In the drawings:
FIG. 1 is a side elevational view of apparatus in accordance with the present invention partly broken away to reveal internal construction; and
FIGS. 2 and 3 are, respectively, front and rear elevational views likewise broken away in section to reveal internal construction; and
FIG. 4 is a fragmentary, enlarged sectional view of the filter bag mounting and adjacent elements.
FIG. 5 is an enlarged, horizontal, sectional view through the fan;
FIG. 6 is a sectional view substantially along the line 6--6 of FIG. 5;
FIG. 7 is a schematic side elevational view of the vibrating means.
The apparatus hereinafter described in detail is presented in a preferred use for transportation to the site where holes have been excavated. For such purpose the equipment is installed on the chassis 11 of a trailer, truck or other suitable vehicle shown only partly in the accompanying drawings and supported above the ground by means of wheels 12. The body is supported above the chassis 11 by means of a mounting plate 13 which is horizontally disposed and spaced upward from the bottom plate 14. Plates 13, 14 are suitably apertured to provide a well 16 for the wheels 12 on either side. Roof 19 is rectangular. The various outer walls and interior bulkheads of the body are reinforced at intervals by angle bars or other stiffeners so that they do not bend inward when the interior of the body is subjected to vacuum.
Extending longitudinally of the interior of the body is a triangular bottom having an apex 16 which has downwardly outwardly slanted sides 17 each disposed at an angle of about 45 degrees with respect to the horizontal. The space 18 below the slanted sides above the mounting plate 13 provides a compartment for storage of hose and the like, to which access is obtained from the rear. As hereinafter explained, dirt falling off the slanted sides 17 slides outwardly to either side 20 of the body so that access to rear and forward doors 21, 22 on either side permits the accumulated dirt to be cleaned out.
Spaced downwardly from the top and disposed centrally of the rear 23 is the duct 24 which is preferably slanted downwardly rearwardly. Flexible hose 26 is installed over the duct 24, the hose gradually diminishing in diameter as it extends outwardly so that it may conveniently be lowered into the bottom of holes in the earth (not shown).
Front panel 31 is formed with an aperture 32 centrally disposed relative thereto and the casing 33 of the blower is installed in registry with opening 32 to draw air out of the body and discharge the air through opening 36.
Extending transversely of the body approximately midway of its length, is middle bulkhead 41 which divides the body into rear and front compartments 42, 43 respectively. Center bulkhead 41 extends vertically approximately midway of the length of the compartment from side to side. Its bottom is closed off by slanted transverse bottom panels 46a which slope forwardly and rearwardly from a transverse horizontal apex 47a at the bottom of bulkhead 41. Rearward of bulkhead 41 extending vertically at the center of the body is a rectangular box 48 having a square opening 49 at the top through which air enters from rear compartment 42 and having similar opening 51 at the bottom through which air is discharged into front compartment 43. Transverse baffles 46,47 are installed in rear compartment 42 to ensure that air sucked in through duct 24 is caused to swirl within the compartment and to contact the side walls 20, roof 19, rear 23 and intermediate bulkhead 41. The swirling of the dirt causes some of the heavier particles to separate out by centrifugal action and as the particles contact the walls of the compartment they are caused to drop to the bottom and then slide outwardly downwardly along sides 17 where they can be removed through doors 21. Normally the very heavy dirt particles or rocks are separated out in compartment 42 and the remainder is drawn through the opening 51 in bulkhead 41 into compartment 43.
Baffle 52, forward of opening 51 causes air to swirl within compartment 43. Most of the remaining particles of dirt drop out of air stream in box 48 and down into the forward compartment 43 along the slanted bottom 53 of the box 48. Other medium sized particles which swirl around inside the compartment 43 contact the walls thereof and separate out from the air stream, falling onto the outward slanted bottom walls 17 and dropping to adjacent forward side doors 22 where the debris may be removed.
The upper portion of forward compartment 43 comprises a filter chamber 56 which is defined by front 31 and middle bulkhead 41 and filter compartment bottom 57 has a plurality of round holes formed therein and surrounding the holes 58 are upstanding cylindrical flanges 59. The number and spacing of the holes 58 is a matter of choice but preferably they are staggered so that a major portion of the area of bottom 57 is apertured and thus a maximum number of holes 58 is afforded. In a preferred form of the invention, there are 28 holes 58 in a pattern of five staggered longitudinal rows with six holes in the outer and center rows and five holes in the intervening rows. The top mounting plate 61 is located directly above plate 57 having similar holes 62 in alignment with holes 58 and likewise having flanges 63 around the holes. Extending between flanges 59 and 63 are filter bags 64 which are cylindrical sleeves open at the bottom and having closed tops 66. The sleeves 64 are formed of filter cloth to trap remaining dirt in the air stream. The bottom edges of bags 64 fit around the flanges 69 and are held in place by clamps 67. The tops 66 are spaced below the top edges of the bags 64 leaving an open cylindrical portion which fits around flanges 63 and held in place by hands 68.
The top mounting plate 61 is suspended from roof 19 by means of springs 71 and a vibrating mechanism 72 is attached between roof 19 and plate 61. Actuation of the vibrator 72 either continuously or intermittently shakes the bags 64 causing dirt trapped therein to fall down to the bottom of compartment 43 and thus reducing the tendency of the filter bags to clog. When it is necessary to remove the bags 64 for replacement or more thorough cleaning, the bands 67-68 are removed and bags 64 are easily displaced.
A satisfactory vibrator 72 is shown more or less schematically in FIG. 7, it being understood that a variety of suitable vibrators is commercially available. Upper shaft is rotatably mounted on roof 19 by means of pillow blocks 74. Lower shaft 76 is mounted on plate 61 by pillow blocks 77. Sprockets 77,78 are fixed to shafts 73,76, respectively, and interconnected by continuous roller-type chain 79. One of the links of chain 79 carries a heavy weight 81, which dynamically unbalances the system. One of the shafts, such as shaft 76, is turned by motor 82 through any convenient means. Weight 81 causes severe vibration as chain 79 passes around its course.
Air in the filter compartment 56 is discharged through opening 32 in the forward wall 31 directly into blower 34 and thence through opening 36 into the atmosphere.
A preferred blower is shown in FIGS. 5 and 6. Forward and rear annular disks 86,87 are supported by drive member 88 on front 89 of casing 33. Casing 33 is of scroll shape, gradually increasing in radius in the counterclockwise direction of rotation of FIG. 6 and opens into discharge duct 36. The central holes 91 of disks 86,87 register with opening 32 in front panel 31.
Extending between parallel sides 86,87 are blades 91 here shown as seven in number and each generally shaped as an air foil. Each blade has a leading edge 92 which is curved outwardly forwardly to a maximum chordal width indicated by reference numeral 93 about one-fourth the radial length of the blade. The trailing edge 94 is substantially radial. The effect of the air foil shape is that the velocity of air movement is greater on the leading surface of the blade than on the trailing surface and this tends to pull air out from the center hole 32 more effectively than in blades of this general type.
In use of the device, the apparatus is transported to the site and the hose 26 inserted into the bottom of one of the holes in the earth. Fan 23 draws air out of the filter compartment 56, forward compartment 43, box 48, and rear compartment 42 thus pulling air up through the duct 24. Such air contains dirt, rocks and other debris which may have fallen into the hole. Baffles 46,47 cause the air to whirl in the rear compartment 42 and gravity, centrifugal force, and the friction of the particles along the walls of the compartment cause the heavy particles to drop out of the air stream to the bottom where they are periodically removed through rear side doors 21. The middle sized and fine particles escape through the opening 49 into the box 48 and thence into the forward compartment 43. Additional dirt falls out of the air stream into box 48 and compartment 43. The remaining dirt is drawn through the opening 58 in the bottom 57 of the filter compartment 56 and the air is sucked through the filter sleeves 64, causing the fine particles to remain on the inside of the filter bags. The air then flows out through opening 32 through the blower 33 into the atmosphere. The vibrators 72 cause the top plate 61 to vibrate and such operation is conducted either intermittently or continuously. The dirt in the pores of the bag 64 falls down through the openings in bottom plate 57 to the bottom of compartment 43. Thus, all the remaining material in the air stream after the air leaves compartment 42 is discharged through doors 22.