BACKGROUND OF THE INVENTION

Field of the Invention

This invention relates to a recovery system for treat- ing a surface, and more particularly to an apparatus for cleaning or coating a surface by projecting a cleaning or coating material upon the surface and for recovering the impacted cleaning or coating material and/or the material removed from the surface.

Prior Art Statement

The process cleaning of a surface by sand blasting, water blasting and the like has been well established in the prior art. Although these cleaning processes have pro¬ gressed the art, the processes still require the projection of a cleaning material such as sand, water or another abra¬ sive material to impact onto a surface. The force of the impact of the cleaning material abrades or cleans the sur¬ face thus removing any overcoating, contaminants, corrosion or the like. Typically, the cleaning material is directed from a nozzle toward the surface by an operator physically holding the nozzle. The force of the cleaning material emanating from the nozzle makes the physical holding of the nozzle difficult for the operator. In addition, the force of the impact of the cleaning material on the surface results in the cleaning material and material removed from the surface such as overcoatings, contaminants, corrosion or the like being projected back from the surface. The cleaning materi¬ al and the material removed from the surface are not only projected back toward the operator but are also dispersed within the surrounding atmosphere. It should be appreciated by those skilled in the art that such an operation is haz¬ ardous not only to the operator but is also hazardous to the environment.

In a spray coating process, a coating material is directed from a nozzle toward the surface. In some cases, a portion of the coating material is projected back and dispersed within the surrounding atmosphere. In a plasma spray coating process, an inert atmosphere is required for the spray coating process. The loss of the inert atmosphere significantly increases the cost of applying the plasma coating. In other spray coating processes, coating solvents are released into the surrounding atmosphere. It should be appreciated by those skilled in the art that such a coating operation is hazardous to the environment.

In my prior patents including U.S. Patents RE 30,289; 4,139,970 and 4,545,156, I replaced the physical holding the of nozzle by an operator through the use of a nozzle holding apparatus. These U.S. patents not only eliminated the difficult task of physically holding the nozzle by an opera¬ tor, but also enabled the use of multiple nozzles to in¬ crease the efficiency of the cleaning operation. In addi¬ tion, since these U.S. Patents eliminated the need for the operator to physically hold the nozzle, the operator could be removed from the immediate area of the cleaning process. Accordingly, the hazard to the operator was substantially reduced through the practice of my prior inventions.

It is a prime object of the present invention to im- prove upon my prior inventions by providing a recovery system for totally collecting the impacted cleaning material and the material removed from the cleaned surface and for totally collecting non-adhering coating material.

Another object of the present invention is to provide an improved apparatus for recovering a cleaning material and material removed from the surface that is safe for both the operator and the environment.

Another object of the present invention is to provide an improved apparatus for recovering a cleaning material and material removed from the surface that is a practical appa¬ ratus and method for such recovery.

Another object of this invention is to provide an im¬ proved apparatus for recovering a cleaning material and a material removed from the surface that has substantially total recovery. Another object of this invention is to provide an im¬ proved apparatus for recovering a cleaning material and a material removed from the surface material that is adaptable to various pre-existing cleaning devices.

Another object of this invention is to provide an i - proved apparatus for recovering a cleaning material and a material removed from the surface material that is mountable on a pre-existing cleaning device for movement therewith.

Another object of this invention is to provide an im¬ proved apparatus for recovering a cleaning material and a material removed from the surface that is light-weight and durable.

Another object of this invention is to provide an im¬ proved apparatus for recovering a cleaning material and a material removed from the surface having a life expectancy commensurate with the life expectancy of blast nozzles.

Another object of this invention is to provide an im¬ proved apparatus for recovering a cleaning material and a material removed from the surface that is economical to manufacture and easy to replace. Another object of this invention is to provide an im¬ proved apparatus for recovering a cleaning material and a material removed from a surface that recovers substantially all of the materials with a minimum vacuum source.

Another object of this invention is to provide an im- proved apparatus for recovering a coating material for totally collecting non-adhering coating material.

Another object of this invention is to provide an im¬ proved apparatus for providing a specialized atmosphere for facilitating a coating process and for recollecting the specialized atmosphere.

Another object of this invention is to provide an im¬ proved apparatus for recovering a treating material which does not contact the treated surface.

The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed as being merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or modifying the invention with in the scope of the invention. Accordingly other objects in a full understanding of the invention may be had by referring to the summary of the invention, the de¬ tailed description describing the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.

SUMMARY OF THE INVENTION

The present invention is defined by the appended claims with specific embodiments being shown in the attached draw¬ ings. For the purpose of summarizing the invention, the invention relates to an apparatus for recovering a treating material with a vacuum source with the treating material is supplied by a pressurized source of treating material for treating a surface. The invention comprises housing having a housing opening with nozzle means connected to the pres- surized source of the treating material secured to a nozzle support. Housing mounting means mounts the nozzle support to the housing enabling the nozzle means to project the treating material through the housing opening to impact onto the surface. A fluid seal means defines a fluid sealing element with fluid seal mounting means mounting the fluid sealing element about the housing opening. The fluid seal means comprises a fluid under pressure flowing between the fluid sealing element and the surface into the housing opening to establish a fluid cushion between the fluid sealing element and the surface for providing a seal between the housing opening and the surface. A vacuum connection means connects the vacuum source to the housing for with¬ drawing non-adhering material from the housing.

In a more specific embodiment of the invention, the fluid seal means includes a plurality of fluid seal ports communicating with a fluid pressure source for establishing a fluid flow from each of the plurality of fluid seal ports into the housing opening between the housing and the surface for providing the seal between the housing and the surface. Preferably, the fluid seal means comprises a plurality of fluid sealing elements being disposed about the housing opening and the fluid seal mounting means independently mounts each of the plurality of fluid sealing elements for enabling each of the plurality of fluid sealing elements to be independently movable for sealing with a curved surface.

Preferably, the housing defines a substantially cylin¬ drical housing internal volume having a first and a second cylindrical end and a cylindrical sidewall. The housing mounting means is disposed proximate the first cylindrical end of the housing for mounting the housing to encompass the nozzle means with the nozzle means being disposed within the housing internal volume of the housing. The fluid seal mounting means is disposed proximate the second cylindrical end of the housing with the fluid sealing element disposed about the housing opening.

In one embodiment of the invention, the nozzle means comprises a plurality of nozzles with the nozzle support being rotatably mounted within the housing. In another embodiment of the invention, the nozzle support includes means for varying a spacing between the plurality of noz¬ zles. In still another embodiment of the invention, the housing mounting means comprises first resilient means for resiliently mounting the housing relative to the nozzle support with the first resilient means being adjustable for adjusting the housing relative to the nozzle means for varying the distance between the nozzle means and the sur¬ face.

The vacuum connection means includes a plurality of angularly orientated vacuum ports disposed proximate the first cylindrical end of the housing adjacent the cylin¬ drical sidewall of the housing internal volume of the hous¬ ing for enhancing the vortex within the housing internal volume of the housing. The invention may include vent means for introducing ambient air into the housing for enabling the vacuum source to withdraw non-adhering treating material from the housing. The vent means may comprise a plurality of directional louvers communicating with the housing inter¬ nal volume through the cylindrical sidewall to direct a fluid into the housing internal volume for creating a vortex adjacent the cylindrical sidewall of the housing internal volume for withdrawing the non-adhering treating material from the housing.

The treatment material may be a cleaning material for cleaning a surface. In this embodiment of the invention, the vacuum source withdraws the impacted cleaning material and the surface material removed from the surface from the housing.

The treatment material may be a coating material for coating a surface. In this embodiment of the invention, the vacuum connection means withdraws non-adhering coating material from the housing. The fluid seal means may include a plurality of fluid seal ports communicating with a pres¬ sure source of a selected gas for establishing a flow of the selected gas from each of the plurality of fluid seal ports into the housing opening between the housing and the surface for providing a gas seal between the housing and the sur- face. The selected gas flow from the plurality of fluid seal ports into the housing opening establishes a selected gas atmosphere within the housing.

The foregoing has outlined rather broadly the more per¬ tinent and important features of the present invention in order that the detailed description that follows may be better understood so that the present contribution to the art can be more fully appreciated. Additional features of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appre- ciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description taken in connection with the accompany- ing drawings in which:

FIG. 1 is a block diagram of the process of the present invention;

FIG. 2 is an isometric view of the apparatus of the present invention cleaning a ship and recovering cleaning material and surface material removed from a cleaned surface of the ship;

FIG. 3 is an enlarged view of a portion of FIG. 2 fur¬ ther illustrating the apparatus of the present invention;

FIG. 4 is a side view of the apparatus of FIG. 3; FIG. 5 is an enlarged side elevational view of the apparatus of the present invention;

FIG. 6 is a left end view of FIG. 5;

FIG. 7 is an enlarged sectional view of the apparatus of the present invention; FIG. 8 is a view along line 8-8 in FIG. 7;

FIG. 9 is a sectional view similar to FIG. 7 with spraying nozzles being disposed in a retracted position;

FIG. 10 is a sectional view similar to FIG. 9 with spraying nozzles being disposed in an extended position; FIG. 11 is a sectional view similar to FIG. 7 with fluid seal means being disposed in a normal position;

FIG. 12 is a sectional view similar to FIG. 11 with fluid seal means being disposed in a depressed position;

FIG. 13 is an enlarged view of a fluid seal shown in FIGS. 11 and 12;

FIG. 14 is a sectional view along line 14-14 in FIG. 13;

FIG. 15 is a sectional view along line 15-15 in FIG. 13; FIG. 16 is a view similar to FIG. 15 illustrating the fluid seal in a pivoted position;

FIG. 17 is a sectional view along line 17-17 in FIG. 15;

FIG. 18 is a view similar to FIG. 17 illustrating the fluid seal in a rotated position; FIG. 19 is a side elevational view of the apparatus engaging a flat surface;

FIG. 20 is a side elevational view similar to FIG. 19 of the apparatus engaging a convex surface;

FIG. 21 is a side elevational view similar to FIG. 19 of the apparatus engaging a concave surface;

FIG. 22 is a sectional view similar to FIG. 7 illus¬ trating the fluid flow paths present during the operation of the apparatus;

FIG. 23 is a block diagram of the forces present during the operation of the apparatus;

FIG. 24 is a side elevational view of a second embodi¬ ment of the apparatus of the present invention;

FIG. 25 is a left end view of FIG. 24;

FIG. 26 is a sectional view of the apparatus of FIG.

24;

FIG. 27 is a sectional view along line 27-27 in FIG.

26; FIG. 28 is a sectional view along line 28-28 in FIG.

26; FIG. 29 is a partial sectional view along line 29-29 in FIG. 28;

FIG. 30 is a sectional view similar to FIG. 29 with spraying nozzles being disposed in an outward position;

FIG. 30A is a left end view similar to FIG. 25 further illustrating the nozzles of FIG. 30;

FIG. 31 is a sectional view similar to FIG. 29 with spraying nozzles being disposed in an inward position;

FIG. 31A is a left end view similar to FIG. 25 further illustrating the nozzles of FIG. 31; FIG. 32 is a left end view similar to FIG. 25 illus¬ trating the nozzles rotated into a counterclockwise posi¬ tion;

FIG. 33 is a left end view similar to FIG. 25 illus¬ trating the nozzles rotated into a clockwise position;

FIG. 34 is an isometric view of the apparatus of FIGS. 24-33 cleaning a ship in a first direction with the nozzles being disposed in an outward position;

FIG. 35 is an isometric view of the apparatus of FIGS. 24-33 cleaning a ship in a second direction with the nozzles being disposed in an inward position;

FIG. 36 is a sectional view of a third embodiment of the apparatus of the present invention;

FIG. 37 is a left end view of FIG. 36;

FIG. 38 is a sectional view of a fourth embodiment of the apparatus of the present invention; and

FIG. 39 is a left end view of FIG. 38. Similar reference characters refer to similar parts throughout the several Figures of the drawings.

DETAILED DISCUSSION

FIG. 1 is a block diagram of the process of the present invention with an example of the apparatus 10 of the inven¬ tion being shown in FIGS. 2-4. The method of the present invention comprises projecting a cleaning material 12 such as an abrasive or other cleaning agent from a nozzle 14 disposed within a housing 16 through a housing opening 18 to impact upon a surface 20, shown as a ship 22 in FIG. 2. Preferably, the cleaning material 12 is supplied to the nozzle 14 from a source of high pressure fluid 23 such as compressed air through hoses 24 in a conventional manner. The impacted cleaning material 12A and a surface material 20A which has been removed from the surface 20 are withdrawn from the housing 16 by a vacuum source 25 through hoses 26 to a separator 27. The separator 27 such as a cyclone separator or the like separates the impacted cleaning mate¬ rial 12A from the surface material 20A for enabling the impacted cleaning material 12A to be reused by the apparatus 10. The surface material 20A and any contaminants 28 there- in can be disposed of in an environmentally safe manner. As will be described in greater detail hereinafter, the housing opening 18 is sealed to the surface 20 by a fluid seal means 30 provided by a source of low pressure fluid 23A through hoses 24A. An example of the apparatus 10 of the invention is shown in FIGS. 2-4 as a sand blasting or water blasting device 31 constructed in accordance with my prior.invention shown in U.S. Patent 4,545,156. The blasting device 31 includes a mobile platform 32 supporting a boom 34 having a proximal end 36 and a distal end 38. The proximal end 36 of the boom 34 is rotationally mounted on the platform 32 along rotational axes 41 and 42, respectively. The boom 34 is telescopically movable along a linear axis 43 for extend¬ ing and retracting the distal end 38 thereof. The nozzle 14 is fixed to a nozzle support 50 which is rotationally mounted to the distal end 38 of the boom 34 along rotational

axes 44-49. The movement of the nozzle support 50 along axes 41-49 provides sufficient freedom of movement for allowing the movement of the nozzle 14 to be controlled by a computer along the curved surfaces of the ship 22. Ac- cordingly. the nozzle 14 moves three dimensional path along the surface 20 of the ship in an automated cleaning process. The specific details of the blasting device 31 shown in FIGS. 2-4 may be had by referring to my U.S. Patent 4,545,156 the content of which is incorporated by reference herein.

FIGS. 5-8 illustrate the apparatus 10 of the present invention illustrating the housing 16 having the housing opening 18 and a lower and an upper annular flange 52 and 54. The housing 16 defines a substantially cylindrical housing internal volume 60 having a first and a second cylindrical end 61 and 62 and a cylindrical sidewall 64 extending about a cylindrical axis 65. The housing opening 18 is defined in the second cylindrical end 62 of the hous¬ ing internal volume 60. The nozzle 14 is shown as a plurality of nozzles 14A- 14D fixed to the nozzle support 50 and aligned with the cylindrical axis 65 of the cylindrical housing internal volume 60. The plurality of nozzles 14A-14D are disposed in a central region 66 surrounded by a peripheral region 68 of the cylindrical housing internal volume 60.

As shown in FIGS. 9 and 10, housing mounting means 70 mounts the housing 16 relative to the nozzle support 50 for enabling the nozzles 14A-14D to project the cleaning materi¬ al 12 through the housing opening 18 to impact onto the surface 20. The housing mounting means 70 comprise first resilient means comprising four air cylinders shown as air cylinders 71 and 72 having rams 71A and 72A for resiliently mounting the housing 16 relative to the nozzles 14A-14D. The air cylinders 71 and 72 extend rams 71A and 72A for adjusting the housing 16 relative to the nozzle 14A-14D for varying the distance between the nozzles 14A-14D and the surface 20.

FIG. 9 illustrates the nozzles 14A-14D being disposed in a retracted position whereas FIG. 10 illustrates nozzles 14A-14D being disposed in an extended position through the movement of rams 71A and 72A. The variation of the distance between the nozzles 14A-14D and the surface 20 varies the pattern of impact of the cleaning material 12 projected from the nozzles 14A-14D onto the surface 20. The movement of rams 71A and 72A also compensates for small variations in distance between the surface 20 and the mobile platform 32 that are beyond the accuracy of movement of the axes 41-49. Preferably, the movement of rams 71A and 72A are controlled by a computer.

The fluid seal means 30 is shown as a plurality of fluid seal elements 80 including a first and a second fluid seal element 81 and 82 having a first and a second fluid seal port 81A and 82A. The plurality of fluid seal elements 80 are mounted by fluid seal mounting means 90 disposed proximate the housing opening 18 for positioning the fluid seal means 30 between the housing opening 18 and the surface 20.

The fluid seal mounting means 90 includes second resil¬ ient means for resiliently mounting the fluid seal elements 80 adjacent to the second cylindrical end 62 of the housing internal volume 60 of the housing 16. The fluid seal mount- ing means 90 includes an inner and an outer annular pneumat¬ ic tubular members 91 and 92 for resiliently mounting the fluid seal elements 80 relative to the lower annular flange 52 extending from the housing 16 as will be described in greater detail hereinafter with reference to FIG. 13. The plurality of fluid seal elements 80 including the first and second fluid seal element 81 and 82 are connected through flexible hoses including flexible hoses 101 and 102 elbows 105 and 106 and flexible hoses 111 and 112 to a plu¬ rality of output tubes including output tubes 115 and 116 of a manifold 120. The manifold 120 is connected through a plurality of inputs including inputs 121 and 122 to the source of low pressure fluid 23A shown in FIG. 2. The

inputs 121 and 122 are secured to the upper annular flange 54 for rigidly supporting the manifold 120.

Fluid under pressure from the source of low pressure fluid 23A is individually supplied to each of the plurality of fluid seal elements 80 to emanate from the plurality of fluid seal ports such as ports 81A and 82A as shown by the arrows to create a sealing fluid cushion 130 between the housing 16 and the surface 20 as shown in FIGS. 9 and 10. FIG. 11 is a sectional view similar to FIG. 7 with fluid seal elements 81 and 82 being disposed in a normal position whereas FIG. 12 is a sectional view similar to FIG. 11 with the fluid seal element 81 being disposed in a normal position and with the fluid seal element 82 being disposed in a depressed position. The inner and outer annular pneu- matic tubular members 91 and 92 in combination with the flexible hoses 101 and 102 and 111 and 112 resiliently and independently mount the first and second fluid seal elements 81 and 82 relative to the lower annular flange 52 of the housing 16. The independent mounting of each of the fluid seal elements 80 enable each of the fluid seal elements 80 to independently move for maintaining the sealing fluid cushion 130 on a curved surface.

FIGS. 13-18 illustrate in greater detail the first fluid seal element 81 comprising a base 140 having sidewalls 141 and 142, an outer end wall 143, an inner end wall 144 and a top wall 145. Preferably, a low friction material 147 is established on a bottom surface 148 of the base 140 for facilitating movement of the fluid seal elements 80 over the surface 20. The outer end wall 143 includes a taper at 149 for facilitating movement of the fluid seal elements 80 over irregularities in the surface 20 such as welding joints and the like.

A tube 150 extends through the top wall 145 and the base 140 with a first end 151 thereof terminating in the port 81A. A second end 152 of the tube 150 is connected to the flexible hose 101 that is connected through the elbow

105 and the flexible hose 111 to the output tube 115 of the manifold 120 as shown in FIGS. 5 and 7.

The apparatus includes plural vent means for intro¬ ducing ambient air into the housing 16. As best shown in FIGS. 8, 17 and 18, a first vent means 161 includes first input vents 170 defined within the plurality of fluid seal elements 80 as illustrated by a first input vent 171 and 172 defined in the first fluid seal element 81 for introducing ambient air into the first fluid seal element 81. The first vent means 161 includes first output vents 180 defined within the plurality of fluid seal elements 80 as illus¬ trated by a first output vent 181 defined in the first fluid seal element 81 in FIGS. 17 and 18 for introducing ambient air into the peripheral region 68 of the cylindrical housing internal volume 60 of the housing 16.

The first input vent 171 is defined in the top wall 145 for communicating with the first output vent 181 defined in the inner end wall 144. Ambient air external the housing 16 enters through upper flange holes 184 in the upper annu- lar flange 54 and through lower flange holes 186 in the lower annular flange 52. The ambient air enters the first input vent 171 and is expelled through the first output vent 181 in the first fluid seal element 81 into the cylindrical housing internal volume 60. Preferably, the first output vent 181 is defined to expel the ambient air in a vortex about the peripheral region 68 of the cylindrical housing internal volume 60 as shown by the arrows in FIGS. 6 and 8.

The inner and outer annular pneumatic tubular members

91 and 92 comprise a plurality of inner annular pneumatic tubular members 191-194 and a plurality of outer annular pneumatic tubular members 195-198. The plurality of inner annular pneumatic tubular members 191-194 and the plurality of outer annular pneumatic tubular members 195-198 intercon¬ nect the lower annular flange 52 and the top wall 145 of the fluid seal element 81 by suitable means (not shown) such as mechanical fasteners, adhesives or the like.

The plurality of inner annular pneumatic tubular mem¬ bers 191-194 are in fluid communication with one another and are connected to an source of low pressure air (not shown) . In a similar manner, the plurality of outer annular pneumat- ic tubular members 195-198 are in fluid communication with one another and are connected to an source of low pressure air (not shown) . The plurality of inner and outer annular pneumatic tubular members 191-194 and 195-198 are indepen¬ dently connected to the source of low pressure air for enabling angular relationship of the plurality of fluid seal elements 80 such as the bottom surface 148 of the first fluid seal element 81 to be varied relative to the lower annular flange 52. Preferably, the plurality of inner and outer annular pneumatic tubular members 191-194 and 195-198 are independently connected to the source of low pressure air for establishing the plurality of fluid seal elements 80 to be parallel to the surface 20.

FIGS. 13-18 illustrate a retaining means 200 shown as retaining springs 201 and 202 extending through sidewall apertures 141A and 142A within the sidewalls 141 and 142 for interconnecting the plurality of fluid seal elements 80. The retaining springs 201 and 202 establish a mechanical engagement between the sidewalls of adjacent fluid seal elements 80. The sidewall apertures 141A and 142A are elongated for enabling the fluid seal elements 80 to rotate as shown by the first fluid seal element 81 in FIGS. 15 and 16 relative to an adjacent fluid sealing element 80. The sidewall apertures 141A and 142A also maintain the mechani¬ cal engagement between the sidewalls of adjacent fluid seal elements 80 during the rotation thereof. The flexible hoses 101 and 111 further facilitate the freedom of movement of the first fluid seal element 81.

The plurality of inner and outer annular pneumatic tubular members 191-194 and 195-198 enable the fluid seal elements 80 to pivot as shown by the first fluid seal ele¬ ment 81 in FIGS. 17 and 18. The independent rotation of the first fluid seal element 81 as shown in FIGS. 15 and 16 and

the independent pivoting of the first fluid seal element 81 as shown in FIGS. 17 and 18 enables the fluid seal elements 80 to maintain the air seal 30 with a curve in the surface 20. The flexible hoses 101 and 111 further facilitate the freedom of movement of the first fluid seal element 81.

FIG. 19 is a side elevational view of the apparatus 10 engaging a flat surface 20B wherein the fluid seal elements 80 are in a normal biased position.

FIG. 20 is a side elevational view similar to FIG. 19 of the apparatus 10 engaging a convex surface 20C wherein the fluid seal elements 80 are rotated as shown in FIGS. 15 and 16 and are pivoted as shown in FIGS. 17 and 18 to main¬ tain the air seal 30 with the convex surface 20C.

FIG. 21 is a side elevational view similar to FIG. 19 of the apparatus 10 engaging a concave surface 20D wherein the fluid seal elements 80 are rotated as shown in FIGS. 15 and 16 and are pivoted as shown in FIGS. 17 and 18 to main¬ tain the air seal 30 with the concave surface 20D.

When the fluid seal elements 80 are rotated as shown in FIGS. 15 and 16 the retaining springs 201 and 202 are able to move within the elongated sidewall apertures 141A and 142A for maintaining the mechanical engagement between the sidewalls of adjacent fluid seal elements 80. The mechanical engagement between adjacent sidewalls of the fluid seal elements 80 creates a seal between the adjacent fluid seal elements 80 for inhibiting any of the impacted cleaning material 12A, the surface material 20A and any contaminants 28 therein from being discharged from the housing 16 through voids or spaces between adjacent fluid seal elements 80.

The plurality of fluid seal elements 80 including the first and second fluid seal elements 81 and 82 pivotably support a plurality of louver panels 210 including louver panels 211 and 212 for directing the ambient air expelled from the first vent means 161 including first output vent 181 into the housing 16.

The first fluid seal element 81 pivotably supports the louver panel 211 through a pivot 211A secured to a mounting 216 extending from the base 145 of the first fluid seal element 81. A spring 218 biases the louver panel 211 into a parallel relationship with the cylindrical sidewall 64 of the housing 16 as shown in FIG. 13. Preferably, the pivot 211A pivots a backplate 222 having a dovetail projection 224. A dovetail recess 226 defined in the louver panel 211 enables the louver panel 211 to be removably secured to the backplate 222 to facilitate replacement of the louver panel 211.

As shown in FIGS. 6 and 8, the plurality of louver panels 210 including louver panels 211 and 212 introduce the ambient air into the housing 16. The plurality of louver panel 210 including louver panels 211 and 212 are angularly mounted relative in an overlapping relationship for retain¬ ing the impacted cleaning material 12A, the surface material 20A and any contaminants 28 within the housing 16. In addition, the plurality of louver panel 210 protect the plurality of inner and outer annular pneumatic tubular members 191-194 and 195-198 and the fluid seal elements 80 from being impacted by rebounding impacted cleaning material 12A, the surface material 20A and any contaminants 28.

The angularlymounting and the overlapping relationship of the plurality of louver panels 210 including louver panels 211 and 212 create a plurality of vent slots therebe¬ tween. The directional or angular relationship of the louver panels 211-214 enables ambient air entering through the upper flange holes 184 to be directed through the vent slots to create a vortex of air flow as shown by the arrows in FIGS. 6 and 8 within the peripheral region 68 of the housing internal volume 60 of the housing 16.

A second vent means 162 includes a plurality of aper¬ tures 240 defined in the sidewall 64 of the housing 16 communicating with a director ring 245. The director ring 245 includes a plurality of angularly disposed orifices 246 for directing ambient air entering the plurality of aper-

tures 240 and being expelled by the plurality of angularly disposed orifices 246 for assisting the creation of the vortex of air flow as shown by the arrows in FIGS. 6 and 8. The second vent means 162 also eliminates the impacted cleaning material 12A, the surface material 20A and any contaminants 28 therein from accumulating on the sidewall 64 of the housing 16.

A third vent means 163 comprises a portion of the air emanating from the fluid seal port 81A and 82A entering into the housing 16 as shown by the arrow. A remaining portion of the air emanating from the fluid seal port 81A and 82A discharges from the housing 16 as shown by the arrow.

The apparatus 10 includes vacuum connection means 250 including a first through fourth angularly orientated vacuum port 251-254 disposed proximate the first cylindrical end 61 of the housing 16 adjacent the cylindrical sidewall 64 of the housing internal volume 60 of said housing 16. The vacuum ports 251-254 define arcuate input slots 251A-254A communicating with output ports 251B-254B of the vacuum port 251-254. The output ports 251B-254B are connected through the vacuum hoses 26 to the vacuum source 25 as shown in FIG. 2 and form a partial helical shape. A housing dome 258 is disposed at the first cylindrical end 61 of the cylindrical housing internal volume 60 for cooperating with the angular- ly orientated vacuum port 251-254 for enhancing the fluid dynamics of the vortex.

The operation of the apparatus 10 can best be described with reference to FIGS. 22 and 23. When the vacuum source 25 is connected to the vacuum ports 251-254, a partial vacuum is established within the cylindrical housing inter¬ nal volume 60. The air seal 30 creates a seal between the cylindrical housing internal volume 60 and the surface 20. The first, second and third vent means 161-163 introduce ambient air into the cylindrical housing internal volume 60 for creating an air flow from the ambient into the housing 16. The air flow from the ambient into the housing 16 is

continuously removed from the cylindrical housing internal volume 60 by the vacuum source 25.

During the operation of the device, the cleaning material 12 is projected from the nozzles 14A-14D onto the surface 20 from the central region 66 of the housing inter¬ nal volume 60. The orientation of the first through third vent means 161-163, and the vacuum ports 251-254 establish the vortex within the housing internal volume 60 of the housing 16 as shown by the arrows in FIGS. 6 and 8. The vortex is confined to the peripheral region 68 the housing internal volume 60 such that the vortex does not interfere with cleaning material 12 being projected from the nozzles 14A-14D onto the surface 20. The air flow from the ambient into the housing 16 and more specifically the vortex, col- lects and removes the impacted cleaning material 12A, the surface material 20A and any contaminants 28 through the vacuum ports 251-254. The impacted cleaning material 12A, surface material 20A and any contaminants 28 are contained within the housing 16 and are removed through the vacuum ports 251-254.

When the apparatus 10 is used in a sand blasting pro¬ cess, the total ambient air [AIR,,.,.] entering the cylindrical housing internal volume 60 of the housing 16 is:

AIR _M = AIR ₁₆₁ + AIR ₁₆₂ + AIR ₁₆₃ [1] and the total air [AIR _in ] entering the cylindrical housing internal volume 60 of the housing 16 is:

AIR _ln = AIB„ + AIR _^ [2] where [ IR _^ ] is the air entering from the nozzles 14A-14D. The total air [AIR _out ] being removed from the cylindrical housing internal volume 60 of the housing 16 by the vacuum ports 251-254 must be:

AIR _< . _ut > AIR _in [3]

When the total air being removed from the housing 16 by the vacuum ports 251-254 is equal or greater than the total air entering the housing 16, substantially all of the impacted cleaning material 12A, surface material 20A and any contami¬ nants 28 are removed from the housing 16.

The fluid seal elements 80 are subjected to four sepa¬ rate forces that must be controlled and balanced for proper operation of the apparatus. The air emanating from the fluid seal ports 80A including the first and second ports 81A and 82A of the first and second fluid seal elements 81 and 82 produces a first force [F _x ] that creates a space the fluid seal elements 81 and 82 from contacting the surface 20. The first force [ F _x ] is variable dependent upon the space 260 between fluid seal elements 81 and 82 and the surface 20. When the space 260 is decreased, the first force [F _x ] is increased whereas when the space 260 is in¬ creased, the force [F _x ] is decreased. Depending upon the type and strength of the surface 20, the first force [F- has a desired value [F _^p ,-]. The fluid seal elements 80 are resiliently mounted by the inner and outer annular pneumatic tubular member 91 and 92. The inner and outer annular pneumatic tubular member 91 and 92 provide a resilient mounting second force [F ₂ ] which is equal to [Fi- _P c]. The partial vacuum produced within the cylindrical housing internal volume 60 of the housing 16 provides a third force F ₃ in opposition to the first force F-* _. produced by the fluid seal elements 80. The fourth force F ₄ is the resultant force applied by the mobile platform 32 and axes 41-49 that is applied through the rams 71A and 72A of the air cylinders 71 and 72. In the desired operation mode, the forces are maintained in equilibrium or

In order to maintain this equilibrium, the apparatus 10 incorporates primary and secondary sensors 270 and 280. Although various sensors may be utilized with the present invention, linear potentiometer or linear variable differen¬ tial transformers have been found suitable for use in the present invention. The primary sensors 270 are distributed about the inner and outer annular pneumatic tubular member 91 and 92. Preferably, four primary sensors 270 including a first and a second primary sensor 271 and 272 in FIG. 22

are disposed in radial alignment with the four rams of the four air cylinders including rams 71A and 72A of the first and second rams 71 and 72. The primary sensors including the first and second primary sensors 271 and 272 sense the relative movement between the first and second fluid seal elements 81 and 82 and the housing 16. The secondary sensor 280 is disposed adjacent to the ram 71A of the air cylinder 71. The secondary sensor 280 sense the relative movement between the housing 16 and the nozzle support 50. When the primary sensors 270 sense an excessive non- uniform compression of the inner and outer annular pneumatic tubular member 91 and 92, a controller 300 adjusts the pitch, roll and yaw of the axes 41-49 of the mobile platform 32 to bring the housing 16 into perpendicular alignment with the surface 20.

When the adjustment of the rams 70A of air cylinders 70 is (1) at an extreme position, (2) beyond the limits of movement of the rams 70A or (3) disrupts the desired patten of the nozzles 14A-14D, the controller 300 will adjust the X, Y and Z axes 41-49 of the mobile platform 32 to reestab¬ lish the desired space 260 or standoff distance set forth in equation [4] as well as the desired extension of rams 70A.

When the primary sensors 270 sense an excessive or insufficient non-uniform compression of the inner and outer annular pneumatic tubular member 91 and 92, the non-uniform compression indicates that cylindrical axis 65 of the cylin¬ drical housing internal volume 60 of the housing 16 is not perpendicular to the surface 20. The non-perpendicular relationship may be caused by either the position of the mobile platform 32 relative to the surface 20 or may be caused by a curvature in the surface 20 as shown by the ship 22 in FIG. 1. The excessive or insufficient non-uniform compression of the inner and outer annular pneumatic tubular member 91 and 92 results in the controller 300 adjusting the axes 41-49 of the mobile platform 32 to reestablish the perpendicular position of the housing 16 relative to the

surface 20 and to reestablish the desired equilibrium set forth in equation [4] as well as the desired extension of rams 70A.

An example of the present invention has been construct- ed with the cylindrical housing internal volume 60 having a diameter of 18 inches and a length between the first and second cylindrical ends 61 and 62 of 14 inches. The majori¬ ty of the components including the housing 16, the fluid seal elements 80 and the plurality of louver panels 210 were constructed of 0.375 inch to 0.75 inch ultra high molecular weight polyethylene (UHMWPY) having a total weight of ap¬ proximately 70 pounds.

Four nozzles 14A-14D were used discharging [AIR _noz ] at 1200 cubic feet per minute (CFM) from the source of high pressure fluid 23. The vacuum ports 251-254 had a total approximately area of 50 square inches and removed approxi¬ mately air [AIR _ou1 at the rate of 2000 cubic feet per minute (CFM) by the vacuum source 25.

Twenty-four fluid seal elements 80 were utilized with each having a surface area of approximately 5 square inches. The source of the low pressure fluid 23A furnished a total of 400 cubic feet per minute (CFM) at 5 to 20 pounds per square inch (PSI) to the fluid seal ports 80A resulting in a total desired first force [Fι_p _f ] of 600 to 2400 pounds. The inner and outer annular pneumatic tubular member 91 and 92 were pressurized at a pressure of 1 to 3 pounds per square inch for producing the second force [F ₂ ]. Four air cylinders 70 were used each having a piston surface area of 1.5 square inches with a pressure of 10 pounds per square inch (PSI) resulting in a fourth force F ₄ of approximately 60 pounds.

The improved apparatus totally collected the impacted cleaning material and the material removed from the cleaned surface making the apparatus safe for both the operator and the environment. Although the apparatus has been shown with reference to a sand blasting device, the invention is adapt¬ able to various types of cleaning devices. The apparatus

is light-weight and durable and has a life expectancy com¬ mensurate with the life expectancy of blast nozzles.

FIGS. 24-28 illustrate a second embodiment of the apparatus 310 of the present invention illustrating the housing 316 having the housing opening 318. The housing 316 defines a substantially cylindrical housing internal volume 360 having a first and a second cylindrical end 361 and 362 and a cylindrical sidewall 364 extending about a cylindrical axis 365. The housing opening 318 is defined in the second cylindrical end 362 of the housing internal volume 360. A first housing end wall 369 is secured to the first cylindri¬ cal end 361 of the housing 316.

The nozzle 314 is shown as a plurality of nozzles 314A- 314C fixed to a nozzle support 350 with the plurality of nozzles 314A-314C being radially aligned with the cylindri¬ cal axis 365 of the cylindrical housing internal volume 360. The plurality of nozzles 314A-314C are disposed in a central region 366 surrounded by a peripheral region 368 of the cylindrical housing internal volume 360. The housing mount- ing means 370 mounts the nozzle support 350 relative to the housing 316 for enabling the nozzles 314A-314C to project the cleaning material 12 through the housing opening 318 to impact onto the surface 20.

As best shown in FIGS. 28 and 29, each of the plurality of nozzles 314A-314C is mounted to a nozzle flange 320A- 320C. The nozzle flanges 320A-320C are secured to the nozzle support 350. The nozzle support 350 comprises an outer disk 321, an inner disk 322 and an inner cover plate 323. As shown in FIG. 28, the nozzle flanges 320A-320C are secured by bolts 323 extending through the nozzle flanges 320A-320C and engaging with bolt holes sets (not shown) defined in the inner disk 322. Preferably, a multiplicity of bolt holes sets (not shown) are defined in the outer disk 321 and the inner disk 322 for enabling the radial position of each of the plurality of nozzles 314A-314C to be varied relative to the cylindrical axis 365 of the cylindrical

housing internal volume 360. A plurality of hoses 324A-324C are secured to the plurality of nozzles 314A-314C.

In this embodiment, the outer disk 321 and the inner disk 322 define three bolt holes sets (not shown) for posi- tioning the plurality of nozzles 314A-314C into three radial position relative to the cylindrical axis 365 of the cylin¬ drical housing internal volume 360.

FIGS. 25 and 29 illustrate the plurality of nozzles 314A-314C in an intermediate radial position relative to the cylindrical axis 365. FIGS. 30 and 30A illustrate the plurality of nozzles 314A-314C in an outward radial position relative to the cylindrical axis 365 whereas FIGS. 31 and. 31A illustrate the plurality of nozzles 314A-314C in an inward radial position relative to the cylindrical axis 365. The selected radial position of the plurality of nozzles 314A-314C relative to the cylindrical axis 365 predetermines the width and intensity of the pattern of impact of the cleaning material 12 projected from the plurality of nozzles 314A-314C onto the surface 20. The outward radial position as shown in FIGS. 30 and 30A provides a wide pattern whereas the inward radial position as shown in FIGS. 31 and 31A provides an intense spray pattern.

The plurality of nozzles 314A-314C are rotatably sealed to the nozzle flanges 320A-320C by rotatable hose couplings 325A-325C as indicated by the arrows. The rotatable hose couplings 325A-325C disposed between the plurality of noz¬ zles 314A-314C and the nozzle flanges 320A-320C prevent binding or deformation of the plurality of hoses 324A-324C during operation of the apparatus 310. As best shown in FIG. 29, the rotatable hose coupling 325A includes a lip 326 received within a recess 327 of the inner disk 322. The inner disk 322 is secured to the outer disk 321 by conventional mechanical means (not shown) such as bolts or the like. The lip 326 is rotatably secured within the recess 327 between the inner disk and the outer disk 321 and 322. A bearing 328 journals the rotatable hose coupling 325A relative to the flange 320A.

The inner disk 321 has a plurality of radially extend¬ ing elongated inner breaches 331 uniformly distributed about the cylindrical axis 365 of the cylindrical housing internal volume 360. The outer disk 322 has a plurality of radially extending elongated outer breaches 332 uniformly distributed about the cylindrical axis 365 of the cylindrical housing internal volume 360.

The inner disk 321 and the outer disk 322 are disposed on an inner surface and outer surface 369A and 369B of the first housing end wall 369. The first housing end wall 369 includes an aperture 369A extending about the elongated inner and outer breaches 331 and 332 of the inner and outer disks 321 and 322. The inner disk 322 includes a shoulder 334 for receiving the first housing end wall 369 therein. When the inner disk 322 is secured to the outer disk 322, the first housing end wall 369 is rotatably secured between the outer and inner disks 321 and 322 for rotatably mounting the nozzle support 350 along the cylindrical axis 365 of the cylindrical housing internal volume 360. An inner plate 323 is secured to the inner disk 322 for providing protection for the inner disk 322 and for closing any of the breaches 332 in the inner disk 332.

As shown in FIG. 28, a drive gear 336 is secured to the outer disk 321. An enclosure 338 is secured to the first housing end wall 369 and contains a motor for driving a power gear (not shown) . Plural idler gears 340 engage with the drive gear 336 to rotate the nozzle support 350 relative to the housing 316. A sensor gear 342 is connected to a position sensor 344 for sensing the rotational position of the nozzle support 350 relative to the housing 316.

FIG. 32 is a left end view similar to FIG. 25 illus¬ trating rotation of the nozzle support 350 sixty degrees in a counterclockwise direction relative to FIG. 25. FIG. 33 is a left end view similar to FIG. 25 illustrating rotation of the nozzle support 350 sixty degrees in a clockwise direction relative to FIG. 25. A rotation of one hundred and twenty degrees of the nozzle support 350 for three noz-

zles 314A-314C enables one of the three nozzles 314A-314C to be disposed in the direction of movement of the housing 316 as will be described in greater detail hereinafter.

The fluid seal means 330 is shown as a plurality of fluid seal elements 380 including a first and a second fluid seal element 381 and 382. The fluid seal means 330 operates in a manner as described with reference to the first embodi¬ ment of the invention. The apparatus includes plural vent means for introducing ambient air into the housing 316 as previously described with reference to the first embodiment of the invention.

FIG. 27 illustrates a plurality of louver panels 410 to create a plurality of vent slots therebetween. The directional or angular relationship of the louver panels 410 enables ambient air to create a vortex of air flow within the peripheral region 368 of the housing internal volume 360 of the housing 316 as previously described.

The plurality of louver panels 410 protect the fluid seal elements 380 from secondary impact and the abrasive effects of the cleaning material 12. Preferably, the plu¬ rality of louver panels 410 are replaceable for extending the operational life of the apparatus 310.

FIG. 27 is a sectional view of the apparatus 310 illus¬ trating a vacuum connection means 550. The vacuum connec- tion means 550 includes a first and second angularly orien¬ tated vacuum port 551 and 552 disposed proximate the first cylindrical end 361 of the housing 316 and adjacent the cylindrical sidewall 364 of the housing internal volume 360 of the housing 316. The vacuum ports 551 and 552 communi- cate with input slots 551A and 552A defined in the housing sidewall 364 as shown in FIG. 26. Preferably, the output ports 551B and 552B are connected through swivel coupling (not shown) and through the vacuum hoses 26 to the vacuum source 25 as shown in FIG. 2. The cross-sectional area of the vacuum ports varies along the length thereof to corre¬ spond to the total area of the input slot input slots 551A and 552A along the housing sidewall 364 of the housing 316.

Accordingly, a equal vacuum and an equal flow of fluid will be established along the input slots 551A and 552A.

When the vacuum source 25 is connected to the vacuum ports 551 and 552, a partial vacuum is established within the cylindrical housing internal volume 360. The air seal 330 creates a seal between the cylindrical housing internal volume 360 and the surface 320. The vent means introduce ambient air into the cylindrical housing internal volume 360 for creating an air flow from the ambient into the housing 316. The air flow from the ambient into the housing 316 is continuously removed from the cylindrical housing internal volume 360 by the vacuum source 25.

During the operation of the device, the cleaning material 12 is projected from the nozzles 314A-314C onto the surface 20. The orientation of the vent means and the vacuum ports 551 and 552 establish the vortex within the housing internal volume 360 of the housing 316 as shown by the arrows in FIG. 27. The vortex is confined to the pe¬ ripheral region 368 the housing internal volume 360 such that the vortex does not interfere with cleaning material 12 being projected from the plurality of nozzles 314A-314C onto the surface 20. The air flow from the ambient into the housing 316 and more specifically the vortex, collects and removes the impacted cleaning material 12A, the surface material 20A and any contaminants 28 through the vacuum ports 551 and 552. The impacted cleaning material 12A, surface material 20A and any contaminants 28 are contained within the housing 316 and are removed through the vacuum ports 551 and 552. FIG. 34 is an isometric view of the apparatus of FIGS. 24-33 cleaning the ship 22 in a first direction. In this example, the nozzle support 350 has been rotated to position the plurality of nozzles 314A-314C such that a lead nozzle 314A leads in the direction of movement of the housing 316 as indicated by the arrow. The trailing nozzles 314B and 314C are aligned substantially perpendicular to the direc¬ tion of movement of the housing 316 indicated by the arrow.

FIG. 34 also illustrates the plurality of nozzles 314A-

314C being disposed in an outward position as shown more fully in FIGS. 30 and 30A. The movement of the housing 316 in the direction indicated by the arrow results in a first clean area 601 of the surface of the ship.

FIG. 35 is an isometric view of the apparatus of FIGS. 24-33 cleaning the ship 22 in a second direction. In this example, the nozzle support 350 has been rotated to position the plurality of nozzles 314A-314C such that a lead nozzle 314A leads in the direction of movement of the housing 316 as indicated by the arrow. The trailing nozzles 314B and 314C are aligned substantially perpendicular to the direc¬ tion of movement of the housing 316 as indicated by the arrow. FIG. 35 also illustrates the plurality of nozzles 314A- 314C being disposed in an inward position as shown more fully in FIGS. 31 and 31A. The movement of the housing 316 in the direction indicated by the arrow results in a second clean area 602 of the ship 22. Since the plurality of nozzles 314A-314C are disposed in the inward position as shown in FIGS. 31 and 31A, the width of the second clean area 602 is narrower that the width of the first clean area 601. However, the cleaning will be more intense due to the higher concentration of the cleaning of the plurality of nozzles 314A-314C disposed in the inward position.

FIG. 36 is a sectional view of a third embodiment of the apparatus of the present invention with FIG. 37 being a left end view of FIG. 36. In this embodiment, the plural¬ ity of nozzles 314A-314C have been removed and a rotatable fluid sprayer 614 has been installed within the housing 316. The rotatable fluid sprayer 614 comprises a tubing support 616 extending through the center of the inner and outer disks 321 and 322 and aligned with the cylindrical axis 365 of the cylindrical housing internal volume 360. The tubing support 616 extends through the inner plate 329. A first and a second fluid jet 621 and 622 are located on opposed ends of a rotatable arm 623. The rotatable arm 623 is

journalled to the tubing support 616 for rotation about the cylindrical axis 365 of the cylindrical housing internal volume 360. Preferably, the first and second fluid jets 621 and 622 are angled for imparting a rotation to the rotatable arm 623 upon discharge of a fluid under pressure from the first and second fluid jets 621 and 622. The third embodi¬ ment of the invention is suitable for use with low pressure cleaning processes such as a water cleaning process or the like. FIG. 38 illustrates a fourth embodiment of the appara¬ tus 710 of the present invention illustrating the housing 716 having the housing opening 718. The housing 716 defines a substantially cylindrical housing internal volume 760 having a first and a second cylindrical end 761 and 762 and a cylindrical sidewall 764. The housing opening 718 is defined in the second cylindrical end 762 of the housing internal volume 760. A first housing end wall 769 is se¬ cured to the first cylindrical end 761 of the housing 716. The nozzle 714 is shown as a plurality of nozzles 714A and 714B fixed to a nozzle support 750. The plurality of nozzles 714A and 714B are disposed in a central region sur¬ rounded by a peripheral region 768 of the cylindrical hous¬ ing internal volume 760. The housing mounting means 770 mounts the nozzle support 750 relative to the housing 716 for enabling the nozzles 714A and 714B to project a coating material 12B through the housing opening 718 to impact onto the surface 20.

In this embodiment, the plurality of nozzles 714A and 714B are shown as plasma guns of conventional design. As should be well known to those skilled in the art, the plasma guns is connected to associated power supplies and other associated equipment (not shown) .

A plasma flame 715 is formed by an electric arc within a stream of the selected gas 12C for producing the plasma flame 715 emanating from each of the plurality of nozzles 714A and 714B. Typically, the selected gas 12C is an inert gas such as argon. Although a plasma gun provides superior

coating in many instances, the loss of the selected gas 12C significantly contributes to the cost normally associated with plasma coatings.

The fluid seal means 730 is shown as a plurality of fluid seal elements 780 including a first and a second fluid seal element 781 and 782. The fluid seal means 730 communi¬ cate with a pressure source of the selected gas 12C for establishing a flow of the selected gas 12C from each of the plurality of fluid seal elements 780 into the housing open- ing 718 between the housing 716 and the surface 20. The flow of the selected gas 12C provides a gas seal between the housing 716 and the surface 20. The flow of the selected gas 12C from the plurality of fluid seal ports into the housing opening 718 also establishes a selected gas atmo- sphere within the housing 716.

The vent means 810 comprises a plurality of louver panels 811 to create a plurality of vent slots therebetween. In this embodiment, the housing 716 is sealed for introduc¬ ing the selected gas 12C from a ports 820A communicating with a manifold 820 into the housing 716 through the plural¬ ity of louver panels 811. The directional or angular rela¬ tionship of the louver panels 811 enables the selected gas 12C to create a vortex of the selected gas 12C within the peripheral region 768 of the housing internal volume 760 as previously described. Accordingly, the selected gas 12C is contained within the housing 716.

The vacuum ports 851 and 852 communicate with input slots 851A and 852A defined in the housing sidewall 764. The vacuum ports 851 and 852 are connected to the vacuum source 25 to withdraw the selected gas 12C from the housing 716 to recover the selected gas 12C thereby.

FIG. 39 is a schematic diagram of the fourth embodiment of the invention shown in FIG. 38. When the vacuum source 25 is connected to the vacuum ports 851 and 852, a partial vacuum is established within the cylindrical housing inter¬ nal volume 760. The flow of the selected gas 12C from the plurality of fluid seal elements 780 create a seal between

the cylindrical housing internal volume 760 and the surface 20. The vent means 810 introduces additional selected gas 12C into the cylindrical housing internal volume 760 for creating a flow of the selected gas 12C in the housing 716. The flow of the selected gas 12C into the housing 716 is continuously removed from the cylindrical housing internal volume 760 by the vacuum source 25.

During the operation of the device, the coating material 12B is projected from the nozzles 714A and 714B along with the selected gas 12C onto the surface 20 from the housing internal volume 760. The vortex is confined to the peripheral region 768 the housing internal volume 760 such that the vortex does not interfere with coating material 12B being projected from the nozzles 714A and 714B onto the surface 20. The flow of the selected gas 12C from the vent means 810 and from the fluid seal elements 780 creates a selected gas atmosphere with the housing 716 for assisting plasma coating process. In addition, the vortex collects and removes any non-adhering coating material 12B through the vacuum ports 851 and 852.

As shown on FIG. 39, the selected gas 12C is withdrawn from the housing 716 by the vacuum source 25. Thereafter, the withdrawn selected gas 12C is passed through a separator 830 for separating any non-adhering coating material 12B from the withdrawn selected gas 12C. The withdrawn selected gas 12C is then passed to a selected gas reservoir 840 to mix with non-used selected gas 12C. The combination of the withdrawn selected gas 12C and the non-used selected gas 12C is drawn by a selected gas compressor 850 for use in the continuous coating process. The introduction of the non- used selected gas 12C replenishes any losses of selected gas in the recovery process.

The fourth embodiment of the invention enables the use of multiple plasma nozzles within the housing 716. General- ly, the cost of the coating material 12B in a plasma coating process is modest but the cost of the selected gas is pro¬ hibitive for many large scale coating applications. The

present invention allows for the recovery of the selected gas 12C and now makes large scale plasma coating an economic reality.

The first and second embodiment of the inventions are more suitable for use with high pressure cleaning such as sand blasting and the like. The third embodiment of the invention is suitable for use in a low pressure cleaning process as well as in a coating process wherein a protective coating is applied to the surface. The fourth embodiment of the invention is suitable for use in a coating process requiring a selected atmosphere with the housing. However, it should be appreciated by those skilled in the art that numerous variation in the design of the present invention may be undertaking within the scope of the present inven- tion.

The present disclosure includes that contained in the appended claims as well as that of the foregoing descrip¬ tion. Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without depart¬ ing from the spirit and scope of the invention.