EP0032810B1 - Continuous coater - Google Patents

Continuous coater Download PDF

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Publication number
EP0032810B1
EP0032810B1 EP81300151A EP81300151A EP0032810B1 EP 0032810 B1 EP0032810 B1 EP 0032810B1 EP 81300151 A EP81300151 A EP 81300151A EP 81300151 A EP81300151 A EP 81300151A EP 0032810 B1 EP0032810 B1 EP 0032810B1
Authority
EP
European Patent Office
Prior art keywords
air
coater
vestibules
vestibule
entrance
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP81300151A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0032810A1 (en
Inventor
James L. Kennon
Lawrence J. Macartney
Gerald W. Crum
John C. Dunn
Donald R. Hastings
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nordson Corp
Original Assignee
Nordson Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nordson Corp filed Critical Nordson Corp
Publication of EP0032810A1 publication Critical patent/EP0032810A1/en
Application granted granted Critical
Publication of EP0032810B1 publication Critical patent/EP0032810B1/en
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B16/00—Spray booths
    • B05B16/90—Spray booths comprising conveying means for moving objects or other work to be sprayed in and out of the booth, e.g. through the booth
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B12/00—Arrangements for controlling delivery; Arrangements for controlling the spray area
    • B05B12/16—Arrangements for controlling delivery; Arrangements for controlling the spray area for controlling the spray area
    • B05B12/18—Arrangements for controlling delivery; Arrangements for controlling the spray area for controlling the spray area using fluids, e.g. gas streams
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B16/00—Spray booths
    • B05B16/60—Ventilation arrangements specially adapted therefor

Definitions

  • This invention relates to a coater and more particularly to a so-called continuous coater.
  • Continuous coaters generally comprise a cabinet through which a product is conveyed, and within which a coating of paint or other material is sprayed from nozzles positioned interiorly of the cabinet. That sprayed material which is not deposited on the product is generally recovered and recycled.
  • a coater in accordance with the invention comprises a coating chamber adapted to have an object conveyed through it from an entrance to an exit, means being provided for spraying an object in the course of passage through the chamber, and an air flow control vestibule extending outwardly from one or both of the chamber's ends and surrounding the entrance and/or exit openings, each vestibule having an outer opening remote from, but longitudinally aligned with, the associated entrance and exit openings of said chamber, wherein the coating chamber is substantially enclosed except for the entrance and exit openings, and air exhaust means are provided opening through one or both side walls of one or both vestibules between the outer opening of the respective vestibule and the entrance/exit opening of the chamber, the air exhaust means creating an air flow barrier in the vestibule without causing significant air flow disturbance in the coating chamber characterised in that the air exhaust means draw air from the surrounding atmosphere, through the complete cross-section area of the outer opening thereof and exhausts the drawn air through respective air collector slots in the side walls of one or both vestibules.
  • the vestibules are connected to an exhaust system including an exhaust fan which is operative to pull outside air into the vestibule in sufficient quantities and at a sufficient velocity to effectively form a barrier to the egress of over- sprayed material through the vestibules.
  • the construction of the vestibule is such that very nearly all of the air pulled into the vestibule to form the air flow barrier is air from outside the booth. Consequently, there is minimal air flow disturbance within the booth and therefore maximum sprayed material utilization.
  • Such a continuous coater not only minimizes the escape of oversprayed material to the atmosphere but additionally, minimizes the quantity of air extracted from the booth. By minimizing air extracted from the booth, it is possible to better control the atmosphere inside the booth and to maintain it saturated or nearly saturated with solvent preventing drying of oversprayed material and facilitating recovery and recycling.
  • there are air flow nozzles located within each vestibule which provide an air curtain flow of air directed toward the coater cabinet. This air flow minimizes the amount of airborne paint or sprayed materail which escapes from the coater cabinet into the vestibules and enables the interior of the cabinet to be maintained saturated or very nearly saturated.
  • a coater in accordance with the invention has the advantage of being operable with lower total horsepower than prior systems which relied upon water flow to generate the negative air pressure to prevent the egress of oversprayed material from the exit and entrance ports of the booth.
  • the system required very high horsepower to pump large quantities of water and still was unable to effect the appropriate air flow.
  • the system of this invention whcih may include liquid scrubbing of the exhaust gases is much more efficient and has beeen proven to require less horsepower than required in water induced air flow systems of the prior art.
  • Another advantage of the system of this invention over water induced air flow systems is that it may be applied to much larger coaters than is practical in a water flow induced system.
  • the coater 10 comprises a coating booth or cabinet 11 having vestibules 12 and 13 extending from opposite ends through which product to be coated interiorly of the booth enters and exits from the booth.
  • the vestibules 12, 13 are connected through duct systems 15,16 to the atmosphere via suction fans 17, 18 respectively.
  • the coater booth 11 comprises a pair of side walls 20, 21, a downwardly sloping bottom wall 22, a ceiling 23 slotted at the top as indicated at 24 to permit the passage of conveyor suspension hooks 25 through the celing, and end walls 26, 27.
  • the end walls are also slotted as indicated at 28 for the passage of the conveyor hooks through those walls.
  • the end walls 26, 27 have entrance 30 and exit 31 ports formed therein through which product suspended from the conveyor hooks 25 may pass into and out of the booth.
  • the two vestibules 12, 13 are identical.
  • One vestibule 12 which is located adjacent the entrance port 30 of the booth will be described in detail. It will be understood that an identical vestibule 13 surrounds the exit port 31 and is attached to the opposite end 27 of the booth.
  • the vestibule 12 functions as an enclosed passageway through which product may enter the spray cabinet 11. It has a pair of side walls 40, 41, a ceiling 42, and a floor or bottom wall 43. These walls 40, 41, 42 and 43 all are sealingly attached to the end wall 26 of the cabinet 11.
  • the ceiling 42 is longitudinally slotted as shown at 42a to facilitate the passage of the conveyor suspension hooks 25 through the vestibule.
  • the slot 42a is closed by overlapping pliable strips 44 which extend across the slot. The pliable strips permit the entry of conveyor hooks but limit over- spray or air from escaping through the slot to the atmosphere and additionally function to prevent the ingress of air into the vestibule through the slot 42a.
  • a central section of each of the side walls 40, 41 of the vestibule taper outwardly from adjacent the outer end 47 of the vestibule so as to provide a rectangular air collector passage 48 on each side of the vestibule.
  • These air collector passages 48 are defined by the outwardly flared sections of the side walls 45, 46, the unflared side wall sections 49, 50 as well as the ceiling 42 and bottom walls 43 of the vestibules.
  • Each of these rectangular collector slots 48 is connected by a funnel-shaped section of conduit 52, 53 to a circular duct 54, 55 respectively.
  • the funnel-shaped sections of ducts 52, 53 are rectangular at the input end which is connected to the air collector slot 48 and are circular at their output end at which point they are connected to the circular ducts 54, 55.
  • each vestibule means for creating an air curtain 108.
  • This air curtain 108 is created by pressurized air discharged from conduits 109 through holes or slots 112 aligned so as to form a flow of air in the vestibule at a location between the air collector slots 48 and the vestibule/coater cabinet 11 interface.
  • These conduits 109 conform to the cross-sectional silhouette of the vestibule opening.
  • the slots 112 in the conduits 109 are operative to create an air flow curtain 108 directed at a selected angle inwardly toward the paint spray cabinet. Flow of air within the air curtains 108 may be adjusted and varied by air pressure regulators 110 located in the air line 111 which supplies the conduits 109.
  • the vestibule's side walls 40, 41 preferably have an outwardly extending flange 56 which forms an extension of the side wall. These flanges extend at an angle of approximately 45° to the vertical plane of the side walls and serve as wind or draft deflectors at the outer opening of the vestibules.
  • each duct 54, 55 extend in a generally horizontal direction but slope slightly downwardly.
  • each duct 54, 55 is connected to a vertical section of expansion chambers 74, 75 respectively which extends up the sides of spray cabinet 11 to baffle boxes 78 and through ducts 58, 59 respectively.
  • each vertical section of duct 58, 59 is joined as illustrated at 60 and connected to the exhaust fan 17.
  • the coater illustrated in Figures 1-5 may be used for spraying either dry powder materials or wet liquid paints or materials onto products passing through the cabinet 11.
  • the coater illustrated in Figures 1-5 is primarily intended to be used for the application of wet paints or liquid sprayed material and for that reason is equipped with a liquid scrubbing system for extracting any airborne paints or sprayed material from the exhaust air before it is exhausted to atmosphere.
  • a liquid spray nozzle 70 To that end there is included in each of the ducts 54, 55 a liquid spray nozzle 70 through which liquid is sprayed to create a liquid scrubber 71 within each of the ducts 54, 55.
  • These liquid scrubbers 71 are effective to catch any air entrained particles and cause those particles to run out of the duct system through a liquid outlet 73 to a separation tank (not shown).
  • the expansion chambers 74, 75 are sized so as to be of approximately twice the cross-sectional area of the ducts 54, 55.
  • a downwardly curved deflector 76 Located within the expansion chamber 74, 75 there is a downwardly curved deflector 76. This deflector is slightly wider than the diameter of the entering duct 54, 55 but narrow enough to allow a cross-sectional area past the deflector at least equal to the area of the entering duct.
  • the downwardly curved deflector in combination with the expansion chamber functions to cause some of the heavier particles entrained in the air stream entering from the ducts 54, 55 to drop out of the entrained air and to flow via the drain pipes 73 to the separation tank.
  • baffles 78 Located above the arcuate deflector 76 in each of the expansion chambers 74, 75 are baffles 78. These baffles function as final stage filters to prevent any liquid/air entrained solid particles from escaping through the duct systems 15 and 16 to the atmosphere.
  • each vertical duct 58, 59 contains a manually adjustable butterfly valve 80 for controlling the relative quantity of air pulled through each of the ducts 58, 59.
  • a manually adjustable butterfly valve 80 for controlling the relative quantity of air pulled through each of the ducts 58, 59.
  • paint is supplied at a relatively high pressure to the nozzles 35 of the rotating arms 36 via a pumping system (not shown).
  • the paint is ejected through the spray nozzles 35 onto product as the product is conveyed through the cabinet.
  • Excess paint is collected from the bottom of the booth via the siphon 38 and is returned to the paint reservoir (not shown).
  • the suction fans 17 and 18 are operated so as to cause air to be pulled from outside the openings 47 of the vestibules into the vestibule collector slots 48.
  • the butterfly valves 80 in each of the vertical legs 58, 59 of the duct system are adjusted so that a relatively even and balanced air flow is maintained through each of the slots 48.
  • the cabinet 11 is substantially sealed against the inflow of air.
  • the construction of the vestibule and collector slots 48 is such that very nearly all of the air pulled into the vestibule to form the air flow barrier is from outside the booth. Consequently, there is a minimum air flow from the interior of the cabinet into the vestibule. Any airborne paint particles or solvent though contained within the air and entering the vestibule through the air curtain 108 is caused to flow by the air stream into the air collector slots 48. Those airborne particles then are removed from the air stream by the liquid scrubber 71 located within the ducts 54, 55. That liquid then flows from the duct system via the drain pipe 73 to a liquid separation tank. The exhaust air flows upwardly through the duct system and out through the exhaust fans 17, 18.
  • the very minimal flow of air from the paint cabinet 11 out through the exhaust system enables the atmosphere within the cabinet 11 to be very closely controlled.
  • the atmosphere within the cabinet can be maintained very nearly solvent saturated and thereby the build-up of paint on the interior walls of the cabinet can be avoided.
  • the coater described hereinabove and illustrated in Figures 1-5 is primarily intended for use in the application of a wet paint or spray material to products passing through the coater, The system though is equally applicable to the application of a dry paint or sprayed material in the form of a powder. Such a system as illustrated in Figure 6 is equally applicable to dry powder or wet spray operation.
  • this coater is identical to the system illustrated in Figures 1-5 except that it has no liquid cleansing system for extracting the airborne particles from the exhaust system.
  • the liquid spray nozzles are omitted from the system as is the liquid drain pipe 73.
  • dry collection filters 90 are placed in the exhaust slots so as to collect any sprayed material which would otherwise be drawn into the exhaust system.
  • this system is identical to that described in Figures 1-5 and operates in exactly the same way to prevent the exhausting of airborne sprayed materials to the atmosphere.
  • FIG. 7 and 8 there is illustrated still a third embodiment of the invention.
  • This embodiment again is primarily intended for use in the coating of liquid paints or spray material onto products passing through the coater.
  • Those components of this embodiment which are identical to components of the embodiment of Figures 1-5 have been given identical numeral designations.
  • the spray cabinet 11, the vestibules 12 and 13, and the system for supplying paint to the booth and for draining paint away from the booth are identical to the corresponding components of the embodiment illustrated in Figures 1-5.
  • the system for preventing the escape of air entrained sprayed particles and/or solvent to the atmosphere is identical through the vestibule exhaust ducts 54, 55 and expansion chambers 74, 75.
  • the baffles 78 though the systems differ in that the two vertical ducts 58 on one side of the paint cabinet 11 are interconnected to a single exhaust fan 100 and the two vertical exhaust ducts 59 on the opposite side of the cabinet 11 are similarly interconnected to a common exhaust fan 101.
  • each vertical leg 58 of the duct system contains its own air balancing butterfly valve or damper 103, 104 and similarly each vertical duct 59 on the opposite side of the cabinet contains its own air flow control butterfly valves (not shown).
  • These air flow control butterfly valves 103, 104 are manually operated and adjusted so as to maintain the flows from the opposite sides of each vestibule balanced, even though those flows are controlled by different fans 100, 101.
  • each duct has its own balancing valve 103, 104, the operation of the system is identical after that air flow balancing is achieved.
  • the primary advantage of the continuous coater described in each of the three embodiments of this application resides in the fact that it maintains a very effective barrier to the egress of sprayed material from the booths through either the product entrance or exit ports. Specifically, the incoming air passing through the vestibule entrance and/or exit port 47 insures that neither the sprayed material nor solvents evolved from those sprayed materials escaped from the coater to the atmosphere. Instead, those materials which might otherwise escape to the atmosphere are entrapped within the duct exhaust system and there removed from the air before the air is exhausted to the atmosphere.
  • Solvent type spray materials include water base paints and sprays in which the water acts as the solvent.

Landscapes

  • Details Or Accessories Of Spraying Plant Or Apparatus (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
EP81300151A 1980-01-14 1981-01-14 Continuous coater Expired EP0032810B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US11166680A 1980-01-14 1980-01-14
US111666 1980-01-14

Publications (2)

Publication Number Publication Date
EP0032810A1 EP0032810A1 (en) 1981-07-29
EP0032810B1 true EP0032810B1 (en) 1986-01-02

Family

ID=22339792

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81300151A Expired EP0032810B1 (en) 1980-01-14 1981-01-14 Continuous coater

Country Status (4)

Country Link
EP (1) EP0032810B1 (enrdf_load_stackoverflow)
JP (1) JPS56108563A (enrdf_load_stackoverflow)
CA (1) CA1162732A (enrdf_load_stackoverflow)
DE (1) DE3173335D1 (enrdf_load_stackoverflow)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT367321B (de) * 1981-03-13 1982-06-25 Voest Alpine Ag Vorrichtung zum einoelen von band- oder tafelf
US4416193A (en) * 1982-02-05 1983-11-22 Nordson Corporation System for vapor precipitation and recovery in a continuous coater
JPS61159070U (enrdf_load_stackoverflow) * 1985-03-26 1986-10-02
US4635585A (en) * 1985-10-15 1987-01-13 Nordson Corporation System for spray coating substrates
DE8712350U1 (de) * 1987-09-11 1987-11-12 Becker, Helmut, Dipl.-Wirtsch.-Ing. Dr.-Ing., 6100 Darmstadt Nebelschmiergerät für Stanzautomaten
AU5536394A (en) * 1993-09-20 1995-04-10 Velie Circuits, Inc. Method and apparatus for soldering circuit boards
DE19645261A1 (de) * 1996-11-02 1998-05-07 Gema Volstatic Ag Vorrichtung zum Sprühbeschichten von Objekten
DE10028553A1 (de) * 2000-06-09 2001-12-13 Itw Gema Ag Pulversprühbeschichtungskabine
CN110918301B (zh) * 2019-11-04 2024-08-16 江苏新金达机械制造有限公司 一种带漆雾回收和自清洗功能的一体化涂装装置
CN110792043B (zh) * 2019-11-26 2021-09-14 合肥名龙电子科技有限公司 一种临时便桥自动补漆设备
CN111992402B (zh) * 2020-08-25 2022-02-15 深圳市聚荣科技有限公司 一种石墨烯喷涂便于定型喷涂的加工设备及方法
CN113414039B (zh) * 2021-05-25 2022-06-14 安庆中船柴油机有限公司 一种船用部件喷涂生产线的气体过滤系统

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1555305A (en) * 1923-07-02 1925-09-29 John A Miller Sanitary spray-painting apparatus
US2560047A (en) * 1947-09-20 1951-07-10 Firestone Tire & Rubber Co Apparatus for electrostatically depositing gas-suspended solids
FR1116915A (fr) * 1954-12-16 1956-05-14 Installation perfectionnée pour la pose en continu de vernis, laques et autres produits de revêtement
GB1134069A (en) * 1966-05-19 1968-11-20 H W Wallace & Co Ltd Apparatus for dusting tacky materials
GB1149335A (en) * 1967-04-20 1969-04-23 Devilbiss Co Spray booth
US3575138A (en) * 1968-01-05 1971-04-20 Nat Steel Corp Electrostatic coating of metal powder on metal strip
FR2144340A5 (enrdf_load_stackoverflow) * 1971-10-29 1973-02-09 Ramellini Angelo
US3750622A (en) * 1971-06-11 1973-08-07 A Repp Anti-pollution ventilation system for spray-type coating chambers
FR2369003A1 (fr) * 1976-11-01 1978-05-26 Ferro Corp Apparei
GB2007833A (en) * 1977-11-10 1979-05-23 Nissan Motor Painting booth on conveyor line
GB2035850A (en) * 1978-11-21 1980-06-25 Cepem Installation for electrostatic deposition of powder on objects

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1555305A (en) * 1923-07-02 1925-09-29 John A Miller Sanitary spray-painting apparatus
US2560047A (en) * 1947-09-20 1951-07-10 Firestone Tire & Rubber Co Apparatus for electrostatically depositing gas-suspended solids
FR1116915A (fr) * 1954-12-16 1956-05-14 Installation perfectionnée pour la pose en continu de vernis, laques et autres produits de revêtement
GB1134069A (en) * 1966-05-19 1968-11-20 H W Wallace & Co Ltd Apparatus for dusting tacky materials
GB1149335A (en) * 1967-04-20 1969-04-23 Devilbiss Co Spray booth
US3575138A (en) * 1968-01-05 1971-04-20 Nat Steel Corp Electrostatic coating of metal powder on metal strip
US3750622A (en) * 1971-06-11 1973-08-07 A Repp Anti-pollution ventilation system for spray-type coating chambers
FR2144340A5 (enrdf_load_stackoverflow) * 1971-10-29 1973-02-09 Ramellini Angelo
FR2369003A1 (fr) * 1976-11-01 1978-05-26 Ferro Corp Apparei
GB2007833A (en) * 1977-11-10 1979-05-23 Nissan Motor Painting booth on conveyor line
GB2035850A (en) * 1978-11-21 1980-06-25 Cepem Installation for electrostatic deposition of powder on objects

Also Published As

Publication number Publication date
JPS56108563A (en) 1981-08-28
EP0032810A1 (en) 1981-07-29
JPS6362265B2 (enrdf_load_stackoverflow) 1988-12-01
DE3173335D1 (en) 1986-02-13
CA1162732A (en) 1984-02-28

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