US3386415A - Coating machine - Google Patents

Description

June 4, i968 E. l.. FABER 3,386,415

COATING MACHINE Filed May 16, 196e 4 sheets-sheet 1 I \'VENTOR: .ELMER L FABBR.

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E. L. FABER CQATING MACHINE June 4, 1968 4 Sheets-Sheer 2 Filed May 16, 1966 INVENTOR. .ELA/IER L. FABER BY 4f @ML TAT .25.

June 4, 1968 E. l.. FABER 3,385,415

COATING MACHINE Filed May 16, 1966 4 Sheets-Sheet 5 E. L. FABER COATING MACHINE `hme 4, 1968 4 Sheets-Sheet 4 Filed May 16, 1966 ATTE/5.

INVENTOR.'

ELA/IER L. FABER.

United States Patent O 3,386,415 COATING MACHINE Elmer L. Faber, Toledo, hio, assignor to Deco Tools, Inc., Toledo, Ollio, a corporation of Ohio Filed May 16, 1965, Ser. No. 550,232 6 Claims. (Cl. 11S-323) ABSTRACT 0F THE DISCLGSURE A painting machine having a. spray housing and two opposed coating stations defined in said spray housing. First and second endless conveyors are mounted for movement along spaced horizontal paths through respective ones of the coating stations. Drive mechanisms transport the conveyors at predetermined individual speeds and each of the conveyors includes work holding means. At least one spray gun is mounted for horizontal circular movement within each of the coating stations. Exhaust means are positioned between the two opposed coating stations for removing contaminated fluid and means are located within the housing for removing at least some of the paint particles from the contaminated uid.

This invention relates to a coating machine and, more particularly, to a coating machine for applying multiple layers of coating to a workpiece, which is being decoratively coated.

A coating machine according to the present invention is used in the decorative painting of numerous articles for example, automobile instrument panels, control panels, and bottle caps. The articles or workpieces to be coated or painted are constructed of formed plastic, metallic die castings, or metallic stampings.

When an instrument panel is decoratively painted, a former plastic workpiece first has a base coat of paint applied to its surface. The panel is then metallized, and nally, a top coat of paint is applied to the panel.

The primary object of the present invention is to provide an improved coating machine having a plurality of coating stations, wherein it is possible to apply a base coat to, for example, a series of instrument panels and simultaneously apply a top coating of paint to another series of instrument panels.

It is another object of the present invention to provide a coating machine which increases production rates in comparison to the prior art apparatus.

It is a further object of the present invention to provide a coating machine having an exhaust system which removes contaminated fluid from a plurality' of coating stations.

It is a still further object of the present invention to provide a coating machine having a plurality of workpiece conveyors which are operated at predetermined speeds and which are suitable for conveying a plurality of workpieces through a respective one of a plurality of coating stations.

Further objects of this invention will become apparent from the following specification and drawings in which:

FIG. 1 is a prospective view of one embodiment of a coating machine, according to the instant invention;

FIG. 2 is a plan view of the coating machine shown in FIG. l;

FIG. 3 is a fragmentary elevational view of the coating machine shown in FIG. 1 and having a portion broken away to show a conveyor drive means;

FIG. 4 is a fragmentary, vertical sectional view taken along the line 4-4 of FIG. 2 and shown on an enlarged scale;

FIG. 5 is a fragmentary, vertical sectional view taken Patented June 4, 1968 aloig the line 5-5 of FIG. 2, and shown on an enlarged sca e;

FIG. 6 is a fragmentary, vertical sectional view taken along the line 6-6 of FIG. 3 and shown on an enlarged scale;

FIG. 7 is an elevational view showing the painting means drive assembly; and

FIG. 8 is a top plan view of the painting means drive assembly shown in FIG. 7.

Briey, the present invention relates to a novel coating machine for applying a coating to a plurality of workpieces. The coating machine includes a spray housing which defines a plurality of coating stations.

A plurality of conveyors are mounted for movement along predetermined horizontal paths. Each of the conveyors is mounted for movement through a respective one of the coating stations. The conveyors have work holding means for retaining a plurality of the workpieces.

Drive means are provided for driving each of the conveyors at a predetermined speed. Painting means are positioned in each of the coating stations and are effective to coat workpieces which are conveyed through the coating station. The coating machine also includes exhaust means which are in communication with the plurality of coating stations for removing contaminated liuid from the coating stations.

Referring to FIG. 1, a coating machine, according to the present invention, is generally indicated by the reference number 15. The coating machine 15 includes a spray housing 16 having an upwardly extending stack 17. A conveyor housing 18 extends perpendicularly through the spray housing 16, and similarly, a conveyor housing 19 extends through an opposite side of the spray housing 16.

Referring to FIG. 4, the spray housing 16 defines two opposed coating stations 20 and 21. The spray housing 16 has a top 22 which mounts opposed drive assemblies 23 and 24 which are adjacent the coating stations 20 and 21. Each of the drive assemblies 23 and 24 includes an equipment platform 25 mounted on the top 22 of the spray housing 16. A motor 26 and a speed reduction unit 27 are mounted on the equipment platform 25. A pulley 28 interconnects the motor 26 and the speed reduction unit 27. A gear 29 is mounted on the output shaft of the speed reduction unit 27 and engages a meshing gear 30 which is mounted on a central rotating shaft 31. The shafts 31 of the opposed drive assemblies 23 and 24 extend through openings 32 and 33 in the top 22 of the spray housing 16.

In the present embodiment, an arm 34 extends perpendicularly outwardly from the lower end of the shaft 31. A pair of spray guns 35 are mounted in opposed relationship on the opposite ends of the arm 34. The rotating shaft 31 is journaled within mounting bearings 36 and defines a plurality of vertically extending passageways (not shown). In the present embodiment, there are three separate passageways provided. A triggering air passageway, an atomizing air passageway, and a paint supply passageway. The respective passageways are in fluid cornmunication at their upper ends with the various supply conduits (not shown). The spray guns 35 are connected to the vertical passageways, located within the rotating shaft 31, by a plurality of conduits 37.

In the present embodiment, the spray guns 35 are conventional air atomization and air transportation type spray guns. However, high pressure liquid type spray guns or electrostatic type spray guns are within the scope of the present invention.

Referring to FIGS. 1, 2, and 3, the conveyor housing 18 has side panels 40, end panels 41, and top panels 42. Referring to FIG. 4, a horizontal guide member 43 is connected to the side panels 40 of the conveyor housing 18. The guide members 43 dene a continuous horizontal path and support a continuous plate-link conveyor 44.

rl`he spray housing 16 defines a pair of spaced openings and 46 through which the continuous conveyor 44 passes. When workpieces supported by the conveyor 44 pass through the opening 45, they enter the coating station 20 and are in coating relationship with thespray guns 35.

Similarly, the conveyor housing 19 has side panels 49, end panels 50, and top panels 51. Guide members 52 (FIG. 4) support a continuous plate-link conveyor 53. ri`he conveyor 53 travels along a continuous horizontal path and passes through openings 54 and 55 which. extend through the spray housing 16. When work which is carried by the conveyor 53 enters the spray housing opening 55 they enter the coating station 21 and are in coating relationship with the spray guns 35.

Referring to FIGS. 2, 3, and 6, the conveyor 44 is driven at a predetermined speed by a conveyor drive assembly 56. Similarly, the conveyor 53 is driven at a predetermined speed by a conveyor drive assembly 57 (see FIG. 2). Each of the conveyor drive assemblies 56 and 57 comprises a motor 58 having a variable speed pulley 59 mounted on its output shaft. The pulley 59 is conducted to a speed reducer mechanism 60 by a belt 61. The output shaft of the speed reducer mechanism 60 mounts a gear 62 and a drive chain 63 extends between the gear 62 and a gear 64 which is mounted on a drive shaft 65. The drive shaft 65 is mounted for rotary movement in upper and lower support bearings 66. Referring to FIG. 6, a conveyor drive gear 67 is secured to the upper end of the rotatable drive shaft 65 and mates with a lower Gear engaging portion of the conveyor 44.

The conveyor drive assembly 56 drives the conveyor 44 at a predetermined speed. In the present embodiment, such speed may be adjusted by the variable pulley 59, however, other speed adjusting means may be utilized. Similarly, the conveyor drive assembly 57 drives the conveyor 53 at a predetermined speed.

Workholding means are connected to each of the conveyors 44 and 53 and are adapted to hold a plurality of serially spaced Workpieces. In the present embodiment the workholding means comprises longitudinally extending workholders 70 (see FIGS. 3 and 6) having downwardly extending projections 71 and 72 and upwardly extending workholding pins 73. Each of the conveyors 44 and 53 has a series of spaced conveyor pins 74 which extend upwardly through a continuous slot 75 dened in the top panels 42 of the Conveyor housing 18 and through a slot 76 in the top panels 51 of the conveyor housing 19.

Referring to FIG. 6, the projection 7'1 which extends downwardly from the workholder 70, has a bore 77 which receives one of the conveyor pins 74. The projection 72 which extends downwardly from the workholder 704 denes a longitudinally extending, open bottomed slot 78 which receives a spaced conveyor pin 74a. The conveyor pin 74a moves relative to the slot 78 when the workholder 70 travels in an arcuate path at the end of a conveyor run. This is illustrated by a workholder 70(a) in FIGS. l and 6. The workholding pins 73 removably support a plurality of serially spaced workpieces 79 (see FIG. 3).

The coating machine 15 includes exhaust means in communication with the coating stations 20 and 21 for removing contaminated fiuid from the coating stations. In the present embodiment, the exhaust means comprises an exhaust fan S2 (see FIG. 4) which is mounted in the upper portion of the stack 17. The fan S2 is driven by an exhaust motor 83 which is mounted on a platform S4 located exteriorly of the stack 17. Preferably, a filter 85 is mounted above the exhaust fan S2 to trap any foreign particles, for example, paint particles, which have not been removed prior to this point. The exhaust fan 812 draws contaminated fluid, for example an air and paint particle mixture, from the coating stations 20 and 21 upwardly through the stack 17, as is indicated by the arrows in FIG. 4.

Washing means are provided for removing paint particles from the contaminated duid which is formed within the coating stations 20 and 21. In the present embodiment, referring to FIG. 4, the wash means includes a reservoir 86 in the lower portion of the spray housing 16. Wash fluid S7 is stored within the reservoir 86 and the level of the wash water 87 is maintained by an overflow conduit 88 (see FIG. 5) which is connected to a drain line S9. The reservoir 36 includes a pump chamber 90 which extends between the adjacent side panels 40 and 49 of the conveyor housings 1S and 19.

Referring to FIG. 5, an entrance line 91 is connected to a supply line 92, for example, a water supply line, to supply addiional wash tiuid to the reservoir 36 when it is required.

A oat controlled valve 93, having a oat 94 is provided in the entrance line 91. When the wash iiuid level falls in the reservoir 86, the float 94 drops and at a predetermined elevation the valve 93 is opened to allow additional wash fluid to enter through the entrance line 91.

A drain line 9S including a drain valve 96 is connected between the reservoir chamber 99 and the drain line 89 and is utilized for reservoir cleaning purposes.

The washing means also includes a distributor system, which is best shown in FIGS. 2, 4, and 5. A pump 97 driven by a motor 98, and having an inlet 99, is positioned within the pump chamber 90. Preferably, a plurality of filters 100 are positioned within the chamber 90 ahead of the pump inlet 99.

The pump 97 has a discharge conduit 101 which carries wash uid upwardly from the reservoir 86 to a header pipe 102. A central conduit 103 and side conduits 104 and 105 are connected to the header pipe 102. A plurality of drop pipes 106 having valves 107 and discharge openings 108 are connected to the side conduit 104. Similarly, drop pipes 109 (see FIG. 4) having valves 110 and discharge openings 111 are connected to the side conduit 105.

A longitudinally extending trough 112 having a downwardly extending apron 113 is mounted in the coating station 20 adjacent the stack 17. Similarly, a trough 114 having an apron 115 is mounted in the coating station 21 adjacent the stack 17.

A longitudinally extending central trough 116 having opposed aprons 117 and 118 is mounted in the stack 17 beneath the central conduit 103. A series of drop pipes 119 are connected to the central conduit 103 and are effective to direct wash uid to the central trough 116.

The discharge openings 108 and 111 of the side drop pipes 106 and 109 are preferably located above the elevation of the spray guns 35 within the coating stations 20 and 21.

In a typical decorative painting operation, the conveyor 44 is actuated and is operated at a predetermined speed. The speed chosen depends on the length of time the workpieces 79 are to remain in the coating station 20. The speed of the conveyor 44 must be correlated with the application rate of the spray guns 35. Similarly, the opposed conveyor 53 is set at a predetermined speed. Normally, the speed of the conveyor 53 differs with respect to the speed of the conveyor 44. In the typical operation herein described, a base coating of paint is applied to the workpieces at the coating station 20, the workpieces are metallized, and subsequently a top coating of paint is applied in the coating station 21. The metallizing step takes place at a location remote from the coating machine 16.

Referring to FIG. 2 a plurality of the workpieces 79 are first positioned on the workholding pins 73 at a work position designated by the letter A. The workpieces are serially spaced, as shown in FIG. 3, and move in a counterclockwise direction through the opening 45 into the coating station 20 (see FIG. 4). The spray guns 35 are mounted for horizontal circular movement within the coating station 20v and apply a base coating of paint to the workpieces 79 as they pass through the coating station 20. When the workpieces 79 reach a work station B (see FIG. 2), the workpieces 79 are removed from the conveyor 44 for an intermediate processing.

At the same time, workpieces 79 are being loaded on the conveyor 53 at work station C (see FIG. 2). These workpieces enter the coating station 21 through the opening 55 and the rotary spray lguns 35 apply a top coating of paint to the workpieces 79 (see FIG. 4). The finished workpieces are removed from the conveyor 53 at work station D (see FIG. 2). At work station D, the workholder 70 is often removed as a unit and the paint applied in the coating station 21 is dried at a position remote from the coating machine 15.

Referring to FIG. 4, as the workpieces 79 pass through the coating stations and 21, some of the paint overspray from the spray guns 35 travels downwardly into the Vwash fluid 87 or mixes with the air within the coating stations forming a contaminated liuid consisting of air and paint particles.

Wash fluid is pumped through the distribution system and is expelled from the openings 108 and 111 into the troughs 112 and 114. Wash uid spills out of the troughs 112 and 114 and onto the aprons 113 and 115. Such uid ows downwardly returning to the reservoir 86. Some of the paint overspray is trapped by the downward flow of wash fluid over the aprons 113 and 115 and is carried into the reservoir 86. These particles and the overspray particles which contact the body of wash uid 87 directly are substantially removed by the filters 100 in the reservoir chamber 90.

The exhaust fan 82 draws the contaminated air-paint mixture upwardly through the stack 17 of the spray housing 16'. Veils of spray wash ow downwardly from the central trough 116 over its aprons 117 and 118 and engage the contaminated uid as it moves upwardly. This removes additional particles of paint from the contaminated fluid. Any remaining paint particles within the uid are substantially removed by the tilter 85 located above the fan 82.

As a way of example, instrument panels may be processed on a coating machine, according to the present invention, at the rate of 425 units per hour, while bottle caps, may be processed at a rate of 'between 10,000 to 18,000 units per hou-r. Of course, the production rate varies depending on the size of the workpieces being coated and the thickness of the respective coatings.

While the present invention has been disclosed in connection with a specific arrangement and disposition of the parts, it should be expressly understood that numerous modifications and changes may be made without departing from the scope of the appended claims.

I claim:

1. A painting machine for applying a plurality of coatings to serially spaced workpieces comprising, in combination, a spray housing, two opposed coating stations detined in said spray housing, iirst and second endless horizontal conveyors mounted for movement along spaced horizontal paths, said iirst conveyor mounted for movement at a predetermined speed through one of such coating stations, said second conveyor mounted for movement at a predetermined speed through the other of such coating stations, work holding means on each of said conveyors for holding a plurality of such workpieces, means for driving each of said conveyors at various predetermined speeds, paintings means positioned in each of said opposed coating stations effective to coat such workpieces, said painting means including at least one spray gun mounted for horizontal circular movement within each of such coating stations, each of said spray guns being vertically spaced above one of said conveyors in spraying relationship with such workpieces, exhaust means in fluid communication with each of such two opposed coating stations for removing contaminated uid from such coating stations and for drawing paint downwardly from said painting means, said exhaust means positioned between said two opposed coating stations, and means within said spray housing for removing at least some of the paint particles from the contaminated iluid.

2. A coating machine, according to claim 1, wherein each of the conveyor drive means comprises a motor, and a speed reduction mechanism operatively connected to said motor, said speed reduction mechanism having an output shaft operatively connected to one of said conveyors.

3. A coating machine, according to claim 1, wherein said painting means includes a .plurality of spray guns mounted for horizontal circular movement within each of such coating stations, said spray guns being vertically spaced above said conveyor in spraying relationship with at least one of such workpieces and means for rotating said spray guns around a vertical axis.

4. A coating machine, according to claim 1, wherein said means for removing paint particles fromthe contaminated uid consists of washing means within said spray housing, and wherein said washing means comprises a reservoir in said spray housing, wash uid within said reservoir, a wash fluid distributor system within said spray housing, said distributor system having at least one discharge opening positioned adjacent said spray guns in each of such coating stations, pump means for supplying Wash fluid from said reservoir to said distributor system, said distributor system being effective to direct wash uid downwardly into engagement with such contarninated fluid whereby paint particles are removed from such contaminated fluid.

5. A coating machine, according to claim 1, wherein said spray housing includes a vertically extending stack, said exhaust means positioned within said stack, said exhaust means etective to discharge fluid from said two opposed coating stations to a location exterior of said spray housing and wherein the means for removing paint particles from such contaminated uid includes washing means within said spray housing.

6. A coating machine, according to claim 5, wherein said washing means comprises, a reservoir in said spray housing, wash fluid within said reservoir, a wash fluid distributor system within said spray housing, said distributor system having at least one discharge opening positioned above the level of said spray guns in each of such coating stations, pump means for supplying wash uid from said reservoir to said distributor system, said distributor system including discharge openings within each of such two opposed coating stations and within said spray housing stack, said distributor system being effective to direct wash liuid downwardly into engagement with the contaminated tluid whereby paint particles are removed from the contaminated Huid.

References Cited UNITED STATES PATENTS 2,227,465 1/ 1941 Roche et al. 118-326 X 2,610,578 9/1952 Paasche 118-326 X 2,719,529 10/1955 Wells 118-326 X 3,056,414 10/1962l Nolte 134--72 X 3,122,235 2/1964` Meeker et al. 134-70 X 3,168,030 2/1965 Wilhelmsson et al. 98-115 FOREIGN PATENTS 222,861 7/ 1959 Australia. 921,402 3/ 1963 Great Britain.

CHARLES A. WILLMUTH, Primary Examiner.

J. P. MCINTOSH, Assistant Examiner.

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