FLUID DELIVERY APPARATUS AND METHOD

Abstract: A fluid delivery apparatus and method is provided wherein either liquid or gaseous fluid is provided from fluid dispenser manifolds (35), via nozzle plates (40) associated therewith, on each side of a path of travel (22) of articles (11) being treated by the fluid, and wherein nozzle openings (41, 42, 43) in nozzle plates (40) cooperate with transverse groove(s) (67) to provide a screen flow of fluid extending transversely of the path of travel (22) of articles (11), and directed toward the articles (11). In the case of the fluid being a liquid, the nozzle openings (41, 42, 43) provide cylindrical filament-like columns of liquid which are rendered by the associated grooves (67) into a generally flat, transversely disposed screen spray of liquid. In the case of the fluid being a gas, the nozzle openings (41, 42, 43) and transverse grooves (67) cooperate to deliver the gas in transversely spaced-apart, transverse, planar zones of gas directed toward the path of article travel (22). In the case of liquid flow, the openings (41, 42, 43) are generally cylindrical, and in the case of gas flow, the openings (41, 42, 43) are generally spaced-apart slotted holes. In the cases of both liquid and gas fluids, one of the grooves (67) and/or nozzles (41, 42, 43) are directed upstream relative to the path of article flow (22). Various adjustments are provided for adjusting the positions of the nozzle plates (40) relative to the path of flow.

Description: Fluid Delivery Apparatus and Method Background of the Invention In various wet processing art involving chemical treatment, such as etching, electroplating and the like, it is known to deliver fluids onto surfaces of articles being treated. In many instances, the articles being treated are printed circuit boards and the like. Often such articles are being delivered along a generally horizontal path and are etched, cleaned, rinsed, activated, dried, etc. , at various stations along the path. Sometime the articles being treated, if they are printed circuit board, have bore holes extending therethrough and it is desired to have the treatment fluid impinge not only on upper and lower surfaces of the boards, but also on bore holes. The treatment of the articles can take place via nozzle arrangements, such as that set forth in U.S. Patent No. 4,789,405, for example. In other instances the treatments may take the form various other fluid delivery, spraying, drying techniques, such as those disclosed in U.S. Patents 4,576,685, 4,017,982, 3,935,041, 3,905,827, or 3,776,800. Various drive techniques for driving the printed circuit boards or other articles through the various treatment stations may be used, such as those set forth in U.S. 4,046,248 or the like. Accordingly, the technical field of this invention is directed to a method and arrangement for treating conductor substrates. Such treatment processes can include the removal of liquid from through holes in conductors boards and from its surface, drying the boards, in addition to cleaning, coating, rinsing, etching, activation and various electrolytic processes. The present invention is directed toward efficient delivery of fluid to articles being treated, and most particularly to conductor boards and the like. In connection with the fluid delivery, slotted tubes, for example have been used, but such are limited in development of the flow upon exiting the orifice or slot, such that the flow stream may dissipate more quickly and lose some of its momentum, even expedientially, as the distance from the substrate being treated increases. Spray nozzles are also use, but such often require large amounts of energy relative to the fluid medium being processed. Additionally, in some instances spray nozzles do not provide the desired level of uniformity in terms of coverage, with a higher percentage of flow and pressure being located at the center of the nozzle spray pattem, and a lesser percentage of flow and pressure outwardly thereof, in that flow and pressure are often substantially reduced as the distance is increased perpendicular to the centerline of the nozzle. Fluid jet injectors have also been used to produce tight columns of flow, but also generally fail to provide a desired level of uniform and complete coverage of the article being treated. Additionally, small injectors require substantially higher pressure to maintain a desired impact of force on the article being treated, which high force impact may always be desirable. Summary of the Invention The present invention provides a method and apparatus for delivering a fluid to printed circuit boards or other articles being treated, as the articles are delivered along a path of travel, by impinging the fluid on the articles from both sides of their path of travel. During such travel fluid is dispensed from nozzles and directed via the nozzles themselves and grooves that connect the nozzles, such that the fluid is provided in the form of a transverse extended screen-like fluid flow from the nozzle openings. The fluid delivered may be either liquid or gas. In the case of a liquid, the nozzle openings disseminate the flow into cylindrical filament-like columns of liquid flow, connected via the grooves into a generally flat transversely disposed planar screen spray of liquid. In the case of a gas fluid, such is provided via nozzle openings and transverse grooves connecting rows of openings, which openings are transversely spaced apart to facilitate disseminating from the openings via the grooves, transverse, planar zones of gas flow directed toward the path of article travel. Optionally, a suction effect may be created by an upstream-converging surface of the nozzle. Various adjustments are provided for the apparatus in accordance with this invention. Additionally, various preferred parameters and structural arrangements are utilized. In some case a row of nozzle openings is directed at an angle to the path of travel, aimed at the upstream direction of the path of travel. Accordingly, it is a primary object of this invention to provide a novel method and apparatus for imparting fluid delivery to an article being conveyed along a predetermined path. It is a further object of this invention to accomplish above object, wherein the fluid delivery is gas for drying an article, such as a conductor board. It is another object of this invention to accomplish the primary object wherein the fluid is a liquid fluid delivery, such as for rinsing, etching, etc. Other objects and advantages will be readily understood upon a reading of the following brief description of the drawings, detailed description of the preferred embodiment and the appended claims. Brief Description of the Drawing Figures Fig. 1 is a longitudinal sectional schematic view, taken through a multi-station apparatus in accordance with this invention, wherein a plurality of etching, rinsing, drying operation are illustrated, and wherein means for imparting fluid delivery above and below articles such as circuit conductors, are illustrated. Fig. 2 is a schematic, perspective view of a circuit board conductor being delivered along its path between upper and lower fluid dispenser manifolds in accordance with this invention, with the manifolds being of a type illustrated above and below the path of travel in Fig. 1. Fig. 3 is an enlarged view of upper and lower fluid delivery manifolds as shown in Fig. 1 , with delivery plates thereof being shown in full lines close to the path of article travel, and in phantom lines spaced moreso from the path of articles travel. Fig. 4 is a view taken generally along the line of IV-IV of Fig. 3, showing the lower end of a nozzle plate surface of an upper manifold fragmentally illustrated. Fig. 5 is a longitudinal section taken generally along the line V-V of Fig. 4, wherein two generally perpendicularly disposed nozzles are illustrated, with an angled nozzle being illustrated, disposed therebetween. Fig. 5A is an enlarged detailed view of one of the nozzles and its associated groove illustrated in Fig. 5, wherein the geometric arrangement thereof is more clearly shown. Fig. 6 is a view similar to that of the liquid dispensing nozzle plate of Fig. 4, but with the nozzle plate of Fig. 6 being specifically adapted for gas dispensing, such as drying air or the like. Fig. 7 is a longitudinal sectional view similar to that of Fig. 5 but taken generally along the line of VII- VII of Fig. 6. Fig. 8 is an enlarged fragmentary longitudinal sectional view taken through an alternative gas delivery pair of manifolds disposed on opposite sides of a path of travel of articles being treated, wherein the surfaces of the manifold plates closest to the path of travel are converging in an upstream direction to facilitate suction of fluid conveyed for impinging surfaces of articles being treated. Detailed Descriptions of the Preferred Embodiments Referring now to the drawings now in detail, reference is first made to Fig. 1, in which a fluid treatment system for articles being conveyed is generally designated by the numeral 10. In this embodiment, the articles being conveyed are printed circuit boards or the like 11, with through-holes such as 12 extending there through, with connecting portions 13 functioning as conductors along portions of the boards, as shown in Fig. 2. In Fig. 1, a plurality of stations 14, 15 and 16 are illustrated, with station 14 functioning perhaps as an etching chamber wherein a suitable etchant may be dispensed onto appropriate surfaces of a printed circuit board or the like, followed perhaps by a rinsing station 15, in which the ecthant liquid (or other treatment fluid) would be rinsed from the articles 11 by means of fluid dispensers 17,18, followed by passage of the articles into another station 16, which may for example be a gas treatment station such as an air drying station wherein air is dispensed via dispensers 20,21 which, like the dispensers 17,18, are disposed on opposite sides of a path of travel 22 for articles being conveyed through the apparatus of the system 10, as shown, from left to right, in the direction of the arrows 23. Each of the stations 14-16 are provided with upper and lower walls, 24,25, side walls 26, inlet and outlet walls 27,28 with appropriate inlet and outlet openings 30,31, respectively. The path 22 of travel of the articles 11 is therefore a longitudinal path of travel through the machine and in the embodiment shown, the path 22 is generally horizontal. Appropriate drive rollers 32 are provided, generally shaft-mounted on transversely disposed shafts, which in turn are driven by any suitable means, such as a drive means for example as shown in U.S. Patent 4,015,706. In instances particularly where the treatment fluid in a given station is liquid, such as for the station 15, and appropriate liquid discharge line 33 may be provided, for discharge to recycling or the like, as desired. With reference to Fig. 2, in particular, the article 11 is shown being delivered substantially horizontally in the direction of arrow 23, beneath a dispenser 17 and above a dispenser 18, it being understood that Fig. 2 could equally well represent dispensers 20,21 as desired. With reference to Fig. 3, it will be seen that the upper dispenser 17 is disposed above the lower dispenser 18 for conveyance of articles 11 therebetween in a longitudinal, generally horizonal path of travel, as shown. The dispenser 17 includes a manifold 35 which receives treatment liquid via a inlet tube 36 or the like, for delivery down through the manifold 35, through a manifold transition plate 37 having a large number of spaced apart transition holes 38 therein, arranged in a row, which extends transversely, substantially between sidewalls 26 of the apparatus as shown in dotted lines in Fig. 3. The fluid thus delivered via conduit 36 and manifold transition holes 38 is thus delivered to a multi- port fluid dispenser nozzle plate 40. The nozzle plate has a plurality of fluid dispenser nozzle openings 41, 42 and 43, arranged in transverse rows, perpendicular to the longitudinal path of travel 22 for articles 11 , and extending generally the transverse length of the manifold 17, substantially completely between opposed sidewalls 26 of the apparatus. A pair of article-engaging rollers 44,45 are provided, carried indirectly (by means not shown) by the manifold 17, respectively shaft-mounted at 46,47, to engage against an upper surface 48 of an article 11 being treated. The purpose of the upper and lower 44,45 is to resist the forces of impingement of fluid being delivered to an article 11 being treated via a manifold on the opposite side of the path of travel 22. Thus, fluid delivered via lower manifold 18 would impart an upward component of motion to the article 11 being treated as shown in Fig. 3, but for the resistance applied by the rollers 44,45 in engagement with an upper surface 48 of the article 11. Conversely, fluid delivered from upper manifold 47 onto an upper surface 48 of the article 11 , would be resisted by the presence of lower roller (unnumbered) carried by the manifold 18. In order to accommodate different thicknesses of article 11, the manifolds 17,18, are vertically adjustable by any suitable means, such that their dispenser nozzle plates 40 may move, for example, between the full line positions therefor shown in Fig. 3, to the phantom line positions shown therefor, for accommodating, for example, a thicker article 11, while still maintaining a desired predetermined spacing between the surface of the plate 40 (for example the lower surface thereof as shown in Fig. 3) and the adjacent surface of the article 11 (for example, the upper surface 48 as shown in Fig. 3). The means for adjusting the positions of the manifolds 17,18 toward and away from the path 22 of article travel can be any suitable means. A representative means is shown whereby an adjustable positionable member 50 is threadedly mounted through a fixed plate member 51, to support transversely extending posts 52 at opposite transverse ends of the manifold 17, whereby turning the treated member 50 may move the manifold 17 from the full line position shown for the post 52 in Fig. 3, to the phantom line position shown therefor also in Fig. 3, for movement of the plate 40 between the full line and phantom position described above. It will be understood that any suitable adjustment means may be provided for changing the relative positions of the manifolds. In the case where the path of travel 22 is a substantially horizontal path as shown, and wherein the rollers 44,45 for the upper manifold engage an upper surface 48 of articles 11 being treated, the weight of the rollers 44,45 may be used to provide the hold-down of the article 11 being treated in resisting upperwardly directly flow from the manifold 18. In such an instance, the shaft, 46,47 for the rollers 44,45, respectively may be mounted in vertical slotted holes 53,54, as shown. Also, it will be noted, with reference to Fig. 4 that a plurality of spaced apart notches 55, spaced generally along the plates 40 between sidewalls 26, may accommodate rollers, 44,45, passing therethrough, as shown in Fig. 3, with clearance, so as not to engage portions of the plate 40 defined by the notches 55. Such allows close placement of the rollers 44,45 to the openings 41, 42 and 43 and similar openings on the opposite path of travel 22 in the manifold 18.

Claims: Claims What is claimed is: 1. Apparatus for fluid treatment of articles being conveyed along a pre¬ determined generally longitudinal path, comprising means for conveying articles along a pre-determined longitudinal path from an upstream direction toward a downstream direction, and: (a) a first fluid dispenser manifold arranged generally transverse to said generally longitudinal path; (b) a second fluid dispenser manifold arranged generally transverse to said generally longitudinal path; (c) said first and second fluid dispenser manifolds being disposed generally opposite each other with the longitudinal article path therebetween; (d) with said first and second fluid dispenser manifolds having respectively associated first and second multi-port fluid dispenser nozzle plates disposed generally transverse of and adjacent to said path, with one said nozzle plate on each side of said path and terminating in a nozzle plate surface nearest said path; (e) with at least one of said first and second nozzle plates having at least one generally transverse row of nozzle openings for dispensing fluid from an associated said manifold therethrough, into contact with articles being conveyed along the predetermined path; (f) transverse groove means extending transverse of said longitudinal path along said nozzle plate surface, connecting the nozzle openings in said nozzle plate surface nearest said path; and (g) with said row of nozzle openings and said transverse groove means cooperating to comprise means for providing transversely extending screen-like fluid flow from said nozzle openings. 2. The apparatus of claim 1, wherein a said nozzle plate has at least two generally transverse rows of nozzle openings, with openings in one said row together with their associated groove means being arranged to dispense fluid generally perpendicular to the predetermined longitudinal path of articles, for impingement of fluid flow onto articles being conveyed therepast, and with the openings in another row, together with their associated groove means being arranged to dispense fluid in an upstream angled direction along said path, for impingement of fluid flow onto articles being conveyed therepast. 3. The apparatus of claim 1, wherein said at least one of said first and second nozzle plates is provided with a plurality of transversely spaced notches; and with a plurality of article-engaging roller wheels being mounted on said apparatus for engagement with articles as they are conveyed therepast; with said wheels being partially disposed in said notches for clearance therewith. 4. The apparatus of claim 1 , wherein at least one said fluid dispenser manifold is provided with means for adjustably positioning said dispenser manifold such that its nozzle openings are adjustably positionable relatively close to and relatively away from the path of article travel. 5. The apparatus of claim 1, with a plurality of article-engaging roller wheels being mounted on said apparatus for engagement with articles as they are conveyed therepast; wherein the path of article travel is generally horizontal; and wherein said roller wheels are adapted to engage an upper surface of an article being conveyed along the path of travel, and with means facilitating vertical movement of said roller wheels to accommodate articles of various thickness. 6. The apparatus of claim 1, wherein the path of article travel is generally horizontal, and wherein said first and second fluid dispenser means are disposed above and below said path of travel. 7. The apparatus of claim 1 , wherein each said fluid dispenser nozzle plate includes a plurality of generally transverse rows of nozzle openings. 8. The apparatus of claim 1, wherein a said nozzle plate has at least two generally transverse rows of nozzle openings, with openings in one said row together with their associated groove means being arranged to dispense fluid generally perpendicular to the predetermined longitudinal path of articles, for impingement of fluid flow onto articles being conveyed therepast; and with the openings in another row together with their associated groove means being arranged to dispense fluid in an upstream angled direction, for impingement of fluid flow onto articles being conveyed therepast; wherein said at least one of said first and second nozzle plates is provided with a plurality of transversely spaced notches; and with a plurality of article-engaging roller wheels being mounted on said apparatus for engagement with articles as they are conveyed therepast; with said wheels being partially disposed in said notches for clearance therewith, wherein at least one said fluid dispenser manifold is provided with means for adjustably positioning said dispenser manifold such that its nozzle openings are adjustably positionable relatively close to and relatively away from the path of article travel; wherein the path of article travel is generally horizontal; and wherein said roller wheels are adapted to engage an upper surface of an article being conveyed along the path of travel; and with means facilitating vertical movement of said roller wheels to accommodate articles of various thickness; wherein each said fluid dispenser nozzle plate includes a plurality of generally transverse rows of nozzle openings; and wherein said first and second fluid dispenser means are disposed above and below said path of travel. 9. The apparatus of any one of claims 1-2, wherein said nozzle openings comprise means for disseminating generally cylindrical filament-like columns of liquid flow, and wherein said groove means comprises means for connecting said columns of liquid flow into a generally flat, transversely disposed, planar screen spray of liquid. 10. The apparatus of claim 9, wherein said nozzle openings comprise a plurality of generally cylindrical holes in each said row. 11. The apparatus of claim 9, wherein said nozzle openings each include a cylindrical taper in the range of 100° to 160° across the diameter thereof, and wherein said groove means has an included angle longitudinally measured, within the range of 30° to 90°. 12. The apparatus of claim 11, wherein said cylindrical taper is approximately 120° and said included angle for said groove means is approximately 60°. 13. The apparatus of any one of claims 1-2, wherein said nozzle openings and associated transverse groove means comprise means for disseminating therefrom, a plurality of transversely spaced apart transverse, planar, zones of gas flow, directed toward the path of article travel. 14. The apparatus of claim 13, wherein said nozzle openings comprise a plurality of transversely elongated slotted holes in each said row, separated by transverse spacings. 15. The apparatus of claim 14, wherein the transversely elongated slotted holes in each said row of a given fluid dispenser nozzle plate are longitudinally aligned with spacings between slotted holes in an adjacent row. 16. The apparatus of claim 14, wherein the depth of said groove means is within a range of 1 to 4 times the width of the slotted holes as measured in the longitudinal direction. 17. The apparatus of any one of claims 1-2 and 13-16, wherein the nozzle plate surface nearest said path, for at least one of said nozzle plates, converges toward said path in an upstream direction, and comprises means, in cooperation with said upstream angled direction of said groove means, for creating a suction effect of fluid impingement on an article being conveyed therepast. 18. A method of fluid treatment of articles being conveyed along a pre¬ determined generally longitudinal path, comprising the steps of conveying articles along a pre-determined longitudinal path from an upstream direction toward a downstream direction, and: (a) providing a first fluid dispenser manifold arranged generally transverse to said generally longitudinal path; (b) providing a second fluid dispenser manifold arranged generally transverse to said generally longitudinal path; (c) disposing the first and second fluid dispenser manifolds generally opposite each other with the longitudinal article path therebetween; (d) with said first and second fluid dispenser manifolds having respectively associated first and second multi-port fluid dispenser nozzle plates; disposing the nozzle plates generally transverse of and adjacent to the path, with one nozzle plate on each side of path terminating in a nozzle plate surface nearest said path; (e) with at least one of the first and second nozzle plates having at least one generally transverse row of nozzle openings for dispensing fluid; dispensing fluid from an associated said manifold therethrough the openings thereof, into contact with articles being conveyed along the predetermined path; (f) providing transverse groove means extending transverse of said longitudinal path along said nozzle plate surface and connecting the nozzle openings in said nozzle plate surface nearest said path via said groove means; and (g) providing transversely extending screen-like fluid flow from said nozzle openings via the transverse groove means. 19. The method of claim 18, including the step of providing a said nozzle plate with at least two generally transverse rows of nozzle openings, with openings in one said row together with their associated groove means being arranged to dispense fluid generally perpendicular to the predetermined longitudinal path of articles, any impinging fluid flow onto articles being conveyed therepast, and with the openings in another row, together with their associated groove means being arranged to dispense fluid in an upstream angled direction along said path, and impinging fluid flow onto articles being conveyed therepast in an upstream angled direction. 20. The method of claim 18, including the step of providing at least one of said first and second nozzle plates with a plurality of transversely spaced notches; and mounting a plurality of article-engaging roller wheels on said apparatus for engagement with articles as they are conveyed therepast; with said wheels being partially disposed in said notches for clearance therewith. 21. The method of claim 18, wherein at least one said fluid dispenser manifold is provided with means for adjustably positioning said dispenser manifold such that its nozzle openings are adjustably positionable relatively close to and relatively away from the path of article travel, and adjustably positioning the nozzle openings relative to the path. 22. The method of claim 18, and mounting a plurality of article-engaging roller wheels on said apparatus for engagement with articles as they are conveyed therepast; wherein the path of article travel is generally horizontal; and engaging said roller wheels with an upper surface of an article being conveyed along the path of travel, with vertical movement of said roller wheels to accommodate articles of various thickness. 23. The method of claim 18, wherein the conveying of articles along the path of travel is generally horizontal, and wherein said first and second fluid dispenser means are disposed above and below said path of travel. 24. The method of claim 18, wherein each said fluid dispenser nozzle plate includes a plurality of generally transverse rows of nozzle openings. 25. The method of claim 18, including providing a said nozzle plate with at least two generally transverse rows of nozzle openings, with openings in one said row together with their associated groove means dispensing fluid generally perpendicular to the predetermined longitudinal path of articles, for impingement of fluid flow onto articles being conveyed therepast; and with the openings in another row together with their associated groove means dispensing fluid in an upstream angled direction, for impingement of fluid flow onto articles being conveyed therepast; wherein said at least one of said first and second nozzle plates is provided with a plurality of transversely spaced notches; and mounting a plurality of article-engaging roller wheels on said apparatus for engagement with articles as they are conveyed therepast; with said wheels being partially disposed in said notches for clearance therewith; providing at least one said fluid dispenser manifold with means for adjustably positioning said dispenser manifold and adjustably positioning its nozzle opening relatively close to and relatively away from the path of article travel; wherein the path of article travel is generally horizontal; and engaging said roller wheels with an upper surface of an article being conveyed along the path of travel; vertically moving said roller wheels to accommodate articles of various thickness; wherein each said fluid dispenser nozzle plate includes a plurality of generally transverse rows of nozzle openings; and disposing said first and second fluid dispenser means above and below said path of travel. 26. The method of any one of claims 1-2, and disseminating from said nozzle openings generally cylindrical filament-like columns of liquid flow, and connecting said columns of liquid flow, via said groove means, into a generally flat, transversely disposed, planar screen spray of liquid. 27. The method of claim 26, including the steps of providing said nozzle openings with a plurality of generally cylindrical holes in each said row. 28. The method of claim 9, including the steps of providing said nozzle openings with a cylindrical taper in the range of 100° to 160° across the diameter thereof, and providing said groove means with an included angle longitudinally measured, within the range of 30° to 90°. 29. The method of claim 28, including providing said cylindrical taper at approximately 120° and providing said included angle for said groove means at approximately 60°. 30. The method of any one of claims 1-2, including the steps of disseminating from said nozzle openings and associated transverse groove means, a plurality of transversely spaced apart transverse, planar, zones of gas flow, directed toward the path of article travel. 31. The apparatus of claim 30, including the steps of providing for said nozzle openings, a plurality of transversely elongated slotted holes in each said row, separated by transverse spacings. 32. The method of claim 31, and longitudinally aligning the transversely elongated slotted holes in each said row of a given fluid dispenser nozzle plate with spacings between slotted holes in an adjacent row. 33. The method of claim 32, including providing a depth for said groove means within a range of 1 to 4 times the width of the slotted holes as measured in the longitudinal direction. 34. The method of any one of claims 1-2 and 13-16, and converging the nozzle plate surface nearest said path, for at least one of said nozzle plates, toward said path in an upstream direction, and creating, in cooperation with said upstream angled direction of said groove means, a suction effect of fluid impingement on an article being conveyed therepast.

Inventors: HIMES RICKY A, HIMES, RICKY, A.
Applicants: ATOTECH USA INC, ATOTECH USA, INC.
Application year: 1996
Main classification: B05D1
IPC codes: B05B9, B05C11, B05D1, B08B3, B08B5, C23F1, C25D5, F26B21, H05K3