US2597021A

US2597021A - Centrifugal spray coating apparatus

Info

Publication number: US2597021A
Application number: US151632A
Authority: US
Inventors: Edward O Norris
Original assignee: Individual
Current assignee: Individual
Priority date: 1950-03-24
Filing date: 1950-03-24
Publication date: 1952-05-20
Anticipated expiration: 1969-05-20

Description

y 2,0, 19,52 E. o. NORRIS 2,597,021

CENTRIFUGAL SPRAY COATING APPARATUS Filed March 24, 1950 5 Sheets-Sheet 1 May 20, 1952 E. o. NORRIS CENTRIFUGAL SPRAY COATING APPARATUS 5 Sheets-Sheet 2 Filed March 24, 1950 INVENTOR EDM/AED O. A/oae/s May 20, 1952 E. o. NORRIS CENTRIFUGAL SPRAY COATING APPARATUS 5 Sheetr s-Sheet 5 Filed March 24, 1950 I? M w j 3nventor Mam/J .fbM/HPP 0 May 20, 1952 E. 0. NORRIS 2,597,021

CENTRIFUGAL SPRAY coATiNG' APPARATUS Filed March 24, 1950 5 Sheets-Sheet 4 9 92 /0 3nnentor fDW/IEQ Mae/ 75 (Ittorneg May 20, 1952 E. o. NORRIS CENTRIFUGAL SPRAY COATING APPARATUS Filed March 24, 1950 5 Sheets-Sheet 5 f M 3. 3 U 6 O ,a m 0/ V .7 l 1 iii 3 1 2 i 0 W, C M ZN J I o 5 l 4 B J B i L |-!.%..;..m n il V i i 8 N 5 :1 Z l I I l l l l l l l l I l I I I I II n L .5 m F ,2

' fDW/IEO 0 A/aQQ/s Qttorneg Patentecl May 20, 1952 UNITED STATES PATENT QFFICE CENTRIFUGAL SPRAY COATING APPARATUS Edward 0. Norris, Westport, Conn.

Application March 24, 1950, Serial No. 151,632

17 Claims.

This invention relates to an apparatus for spraying moving objects which are capable of being fed continuously through the spray zone, and more particularly to a centrifugal sprayer for pipes, rods, or the like, which are adapted to be advanced through the spray zone either individually or by means of a traveling conveyor.

It is an object of the invention to provide an apparatus of the above type having novel and improved details of construction and features of operation.

A more specific object is to provide a centrifugal paint sprayer having means producing a uniform spray zone through which the objects are fed.

Another object is to provide a device of the above type which is suited for continuous operation on a commercial scale.

Various other objects and advantages will be apparent as the nature of the invention is more fully disclosed.

This application is a continuation-in-part of my co-pending application Serial No. 710,358 filed November 16, 1946, for Spraying Apparatus, now abandoned.

In accordance with the present invention the paint or other liquid to be sprayed is fed to a rotating collector case which is mounted for rotation about a horizontal axis and is driven at a speed suited to maintain a peripheral film of liquid due to centrifugal force. A plurality of centrifugal distributors are arranged at spaced points around the circumference of the rotary case and are so positioned that their peripheral edges dip into the liquid film in the case and pick up the liquid therefrom. The distributors are driven by the moving film at a rate to discharge the liquid centrifugally as a fine spray entirely within the confines of the rotary case. The article to be sprayed, such as a pipe or rod, ora series of articles on a conveyor, are fed axially through the rotating case for receiving a uniform coating of the sprayed liquid. The spray which is not applied to the surface of the articles is intercepted by the rotary case and returns to the peripheral film.

In one embodiment a, pipe or rod to be coated is fed axially through the device by means of suitable feed rollers. The roller in contact with the coated pipe on the discharge side of the device may be provided with a plurality of pins which are arranged to support the pipe without injuring the coating. In the case of small articles, a traveling conveyor may be provided in the form of a plurality of spaced parallel wires which carry 2 the objects through the spray zone. Suitable wiper means may be provided for removing the liquid from the conveyor wires so as to prevent a coating from building up thereon. i

Although the novel features which are believed to be characteristic of this invention are pointed out more particularly in the claims appended hereto, the nature of the invention will be better understood by referring to the following description, taken in connection with the accompanying drawings forming a part thereof, in which certain specific embodiments are set forth for purposes of illustration.

In the drawings:

Fig. 1 is a transverse vertical section through a spraying device embodying the present invention taken on the line l-l of Fig. 2;

Fig. 2 is an axial section taken on the line 22 of Fig. 1;

Fig. 3 is a fragmentary section of the feed spout and control valve taken on the line 3-3 ofFig. 2;

Fig. 4 is an enlarged fragmentary section of a distributor taken on the line 4-4 of Fig. 1, but showing the distributor adjusted at an angle to the axis of the case;

Fig. 5 is a section through the distributor taken on the line 5-5 of Fig. 4; Y

Fig. 6 is a side elevation of a spraying device embodying the present invention, including a traveling conveyor for conveying small objects through the device;

Fig. 7 is a top plan view of the spraying device of Fig. 6; a

Fig. 8 is a detail view similar to Fig. 4 showing a further embodiment of the invention; and

Fig. 9 is a section taken on the line 9-9 of Fig. 8.

Referring to the embodiment of the invention shown in Figs. 1 to 5, the. device is shown as comprising pedestal brackets [0 in which a pair of supporting rings I2 and I3 are secured by suitable means. The ring l2 carries a plurality of horizontal brackets l5 which support a ring IT. The ring I? is provided with a plurality of spaced bosses l8 carrying shafts [9 on which guide rollers 20 are journaled. The guide rollers 20 are provided with raised flanges 2| which support annular flanges 22 of a rotating case 23. The case 23 between the flanges 22 is provided with a V-shaped groove 24 which is adapted to receive a V-shaped driving belt 25. The rollers 20 are grooved between the flanges 2| to provide clearance for the belt 25. The belt 25 is driven by a pulley 26 carried by the shaft 21 of a driving motor 28. The rotary case 23 includes an annular dished section 30 which is adapted to receive and carry the rotating film of liquid to be sprayed.

The liquid to be sprayed is fed from a container 35 through a duct 35 to a pivoted feed spout 31. The spout 3'! is provided with a cylindrical journal 38 (Fig. 3) which is carried on a cylindrical portion 39 of the duct 35. The

portions

38 and 39 are provided with feed slots 40 and 4| respectively which are normally aligned to permit the liquid to feed through the open end of the spout 31. However, the size of the opening is altered by pivotal movement of the spout 31 due to contact with the liquid film in the case 23 and is arranged to cut off the feed 4 of liquid when the film reaches a predetermined thickness. In this way the liquid feed is automatically controlled so as to maintain a peripheral film of predetermined thickness in the rotary case 23. Cut off means may also be provided to stop the liquid feed when the case is at rest.

The ring I3 carries a plurality of forwardly extending brackets 42 to which a ring 43 is attached. The ring 43 carries an annular shield 44 having a peripheral lip 45 which is adapted to collect any spray which engages the shield 44 and to return the same to the lower side of the case 23.

The ring 43 carries, at spaced points around its periphery, bosses 46 (Figs. 4 and in which bushings 41 are journaled. Bushings 4'5 carry shafts 48 to which a plurality of cupped discs 49 are attached. The discs 49 may be spaced by suitable spacing washers 50 and may be secured to the shaft 48 by means of a lock nut 5i. The cupped discs 49 are each provided with conical inturned flanges 52 which are positioned to dip into the film of liquid within the rotary case 23. The axis of the shaft 48 extends at an angle to the axis of the bushing 41 so as to permit angular adjustments of the shaft 48. The axes of the bushing 4'5 and shaft 48 preferably intersect at about the center of the distributor disc assembly so that the angular adjustment of the distribution about the point of intersection is effected. V r 7 I The above adjustment is effected by means of a segmental plate 53 carried by thebushing t! and provided with an arcuate slot through which a set screw 54 extends. I

The shaft 48 is provided with a slinger ring 55 which is adapted to throw off any liquid which flows along the shaft 48 and prevents the same from entering the bearing. A circular shield 55 is also provided which extends through the shield 44 for further shielding the bearing of the shaft 48 against the entrance of the sprayed liquid.

Referring to Figs. 1 and 2, the article to be sprayed is shown as a pipe 60 which is continuously fed by suitable means not shown over a V-shaped guide roller 6| mounted on a bracket 62 carried by a post 63 which is slidable in a split support-64 and is provided with a rack 35 engaged by a gear 66 for adjusting the elevation of the roller. The post 63 is clamped in its adjusted position by means of a clamping screw 61. A'hold down roller is also provided for holding the pipe 60 in position on the guide roller 6|. The roller 10 is mounted onbracket H which is pivoted on pins 12 to arms 13 forming a part of the bracket 62. I

The coated pipe is guided from the device by a guide roller mounted on brackets 16 car-' ried by a post 1! which is secured in a split support 18 and is provided with a rack 13 meshing with an adjustment gear 80. The post 17 is clamped in adjusted position by means of a clamping screw 8!. In the embodiment shown the guide roller 15 is provided with a plurality of pins 84 around its surface which are adapted to engage and support the coated pipe. The pins present a minimum surface in contact with the coated pipe and due to the fact that the coating is still in a fluid condition any pin marks in the coating are immediately removed by the natural flow of the liquid.

In the embodiment shown four sets of centrifugal distributors are located at equidistant points around the periphery of the rotary case. It is to be understood, however, that any desired number of distributors may be used depending upon the spray characteristics required. Heating coils I20 may be disposed about the rotary case 23 to permit the device to be used to spray hot melt materials. I

In the operation of this device the pipe or other article to be sprayed is advanced axially through the machine while the rotary case 23 is driven at a high rate of speed such as 2,000 B. P. M. by the motor 28 and belt 25. The paint or other liquid to be sprayed is fed from the reservoir 35 through the duct 36 and spout 31 into the rotating case. The liquid is immediately picked up by the rapidly rotating case and is caused to form a peripheral film thereon. This film is maintained at a predetermined level by the automatic valve provided by the pivoted spout 3i.

The periphery of the distributor discs dip in the film of liquid and are driven thereby at approximately the same peripheral speed as the collecting case. The liquid is picked u by the flanges 52, first traveling inwardly on the discs 49 toward the axis and then being thrown outwardly in a tangential direction in the form of a finely atomized spray which completely surrounds the distributor disc. A portion of this spray contacts with 'thepipe which is continuously advancing axially through the case and the remainder of the spray is intercepted by and retained within the collecting case 23 for re-spraying. The shield 44 is shaped to intercept any spray which passes through the open end of the case and returns the intercepted spray to the rotating case.

It is to be noted that the distributor discs are shown as adapted to be rotated by the force of the liquid film into which they dip, although positive mechanical drive means may be used if desired. These discs are preferably adjusted, by actuating the 'arcuate plates 53, so that the contacting peripheral edges of the discs cut the rotating film at an angle'to the direction of movement of the film as shown in Fig. 5, to facilitate picking up the liquid by the distributor and also t agitate the film and prevent separation of the pigment from the liquid. The discs 'may also be inclined with respect to the transverse plane of the case as shown in Fig. 4 to cause the spray to be projected across the interior of the case-in an inclined direction to facilitate a uniform coating of all surfaces of the article being sprayed.

While the distributors have been shown as comprising a plurality of spaced discs, it i to be understood that the number of discs may be varied and that in some instances a single disc may be used, depending upon the amount of spray required. The discs may be'coated with rubber or other flexible material if necessary for spraying abrasive materials, such a for sand blasting. In certain instances hard metal discs may be used directly for sanding.

In the embodiment shown in Figs. 6 and 7 the rotating case, distributors and paint feed means are similar to those previously described and have been given corresponding reference numerals. This embodiment, however, includes a traveling conveyor comprising a plurality of parallel conveyor wires 90 mounted on rollers 9| and 92 and arranged to pass through the rotary case for conveying a plurality of small articles 95 therethrough. In the embodiment shown, the roller 9| is mounted on a pedestal 96 and the roller 92 is mounted on a pedestal 01, the pedestals being carried by suitable base 00. The rollers 9| and 92 are so arranged that the conveyor wires are inclined downwardly so that the articles 95 are passed through the spray zone in a downwardly inclined position. This facilitates applying the spray to the forward and rear ends of the articles as they pass through the spray zone. The conveyor wires 30 return on the outside of the rotary case over a roller 09 which is carried in the pedestal brackets I0.

Suitable wiper means shown as bars I00 of rubber or the like are positioned to wipe the conveyor Wires 90 in advance of the roller 02. A trough I0! is provided beneath the wipers I00 to receive the liquid which is removed from the conveyor wires and to return the same to the rotary case 23. The wipers I00 prevent the liquid from building up on the conveyor wires 00.

The articles 05, after being coated, are lifted from the conveyor wires 00 before reaching the wipers I00 by means of an additional set of conveyor wires I04 which are fed around rollers I and I00 and extend between the respective conveyor wires 90. The rollers I05 and I00 are shown as mounted on pedestals I01 and brackets I08 respectively. The painted articles 05 are discharged from the conveyor wires I04 to a platform I09 mounted on the bracket I03. Suitable drive means indicated as chains H0 and H2 are arranged to drive the rollers 92 and I06 for feeding the articles 95 through the machine and delivering them to the platform I03. The chain H0 is arranged to engage sprockets II3 and H4 respectively carried by rollers I05 and 92. The chain II2 extends between the sprockets on the roller 92 and the roller I06. The shaft II! of the roller I05 is driven from the motor by means of a pair of beveled gears IIO which may be selected to give the desired speed ratio.

This embodiment of the invention is adapted for conveying small articles through the rotating case and it is to be understood that the particular type of conveyor means may be varied as desired. The articles may be painted, coated, or sand blasted, for example, according to the material sprayed.

In the embodiment of Figs. 8 and 9 the case 23' which is generally similar to the case 23 of Figs. 1 to 7 is provided with an annular channel which receives the film of liquid. The distributor comprises a plurality of discs I30 mounted on a bracket I3I carried by a shaft I32 which is journaled in a bearing I33 in a sleeve I34 which is adjustably secured in a fixed bracket I35 attached to the ring I3, and is clamped by a wing nut I30. The shaft I32 carries a slinger ring I31 and is secured against end play in the sleeve I34 by set screws I and MI. Power is supplied by a flexible shaft I42 which is keyed to the shaft I32 and is enclosed'in'a casing I43 secured to'the sleeve I34. For feeding liquid from the case 23' to the distributor discs I30 a scoop I50 is provided which is attached to the sleeve I34 and has an open end I5I facing the advancing liquid film in the channel 30. The scoop I50 is formed with a hub I52 extending around the shaft I32 within an axial" bore of the discs I30 and having a slot I53 through which the liquid flows to the inner periphery of the discs I30 where it is picked up by the discs and projected outwardly as a centrifugal spray which is intercepted by the case 23' and forms a spray zone lying entirely within the case.

The scoop I50 is adjusted in the channel 30' by the wing nut I35.

A plurality of such driven distributors may be disposed around the case as desired. The medium to be sprayed is passed axially through the case as in Figs. 6 and 7 or the medium may be inserted and withdrawn from the same end of the case if desired.

Although certain specific embodiments of the invention have been shown for purposes of illustration, it is to be understood that the invention is capable of various uses and that changes and adaptations may be made therein as will be readily apparent to a person skilled in the art. The invention is only to be restricted in accordance with the scope of the following claims.

What is claimed is:

1. A spraying apparatus comprising a rotary collecting case having an open end and a grooved surface forming an annular channel to retain a spray-forming material to be sprayed, means for supplying said material thereto for spraying, means for driving said case to cause said material to form a peripheral film in said channel, a centrifugal distributor having a rotatable disc, means mounting said disc to rotate in said case in a plane intercepted by said case around its entire periphery to form a spray zone confined entirely within said case, said distributor including means picking up said material for spraying r from said film and supplying said picked up material to said disc, and means feeding an object to be sprayed through the open end of said case.

2. A spraying apparatus comprising a rotary collecting case having open ends and a grooved surface forming an annular channel to retain a spray forming material, means for supplying said material thereto for spraying, means for driving said case to cause said material to form a peripheral film in said channel, a centrifugal distributor comprising a rotatable disc mounted to dipinto said film of material and rotating in a plane intercepted by said channel, said disc being arranged to pick up material from said film and to discharge the same centrifugally in the form of a spray in a direction to be intercepted by the rotating case, and means for feeding objects to be sprayed through said case.

3. A spraying apparatus comprising a rotary collecting case having open ends and a grooved surface forming an annular channel to retain a spray-forming material, means for supplying said material thereto for spraying, means for driving said case to cause said material to form a peripheral film in said channel, a centrifugal distirbutor comprising a freely rotatable disc mounted to dip into said film of material and to be driven thereby, said disc being arranged to pick up material from said film and to discharge the same centrifugally in the form of a spray in a direction to be intercepted by the rotating case,

and? means for feeding fobjects to :be sprayed:

through said case.

4. A, spraying apparatus comprising a; rotary collectingcase having open ends andxa grooved;

surfacejorming an annularzchannel to retain a sprayeforming material, means for supplyingsaid materialsthereto fori'spraying, means for driving said: case :toicause said material to'form a pee;

ripheralfilm in said channel, a centrifugal dis.--

tributor comprising a freely rotatable disc.

mountedto dipintosaid film of material andto bexlrlven thereby, said disc beingarrangedlto pickupmaterial from said film and todischarge the same centrifugally. in the form of'asprayinz collecting case .havingopen ends and, a grooved surface, forming uan annular channel to. retain: a

sprayeformingmaterial, means for supplyingsaid through, the roller on the discharge side having raised. members to present limited contactareatothe. coated rod.

6. A sprayingapparatus' comprising a rotary collecting case having open ends and a grooved surface forming an annular channelto retaina spray-forming material, means for supplying said materialthereto for spraying, means for driving said case to cause said material to form a poripheral film in said channel, a-centrifugal dis tributor-comprising a freely rotatable disc mount,- ed to dip into said film of material and ,to be driven thereby, said disc being arranged to pick up material from said film and to discharge the same centrifugally in the form of a spray in a directionto be'intercepted by the rotating case, and endless conveyor means comprising spaced parallelwiresextending through said case axially to convey articles to be sprayed therethrough.

'7. A spraying apparatus comprising a rotary collecting case having open ends and a grooved surface, forming an annular channel to receive a spray-forming material, means for supplying said,

materialthereto for spraying, means for driving saidzcaseto cause said material to form a peripheral, filmtin said "channel, a centrifugal distributor comprising a freely rotatable disc mountedto dip into said film of material and to be driven thereby, saiddisc being arranged to pick up material from said film and to discharge the same centrifugally in the form of a spray in a direction to beintercepted by the rotating case, endless conveyor means comprising spaced parallel wires extending through said case axially to convey articles to be sprayed therethrough, and wiper means on the discharge side of said caseto wipe the sprayed liquid from said wires.

8; A spraying apparatus comprising a rotarycollecting case having open ends and a grooved surface forming an annular channel to retain a spray-forming material, means for supplying said materiallthereto for spraying, means for driving saiCL'case tocause said material to form a peripheralfilm in said channel; a centrifugal dis-xtributor comprising a freely rotatabledisc mount-- edtodipinto said film-of material ,and to be driven thereby, said disc, beingarranged to pick-- up materialsfromsaid film and to discharge the same centrifugally in the form of a spray. in a direction to be intercepted by the rotatingjcase, endless conveyor means comprisingspaced par-.- allel wires extending through said case axially to.-

convey articles to be sprayed therethrough, wiper means. on the discharge side of said case to wipe the sprayed material from said wires, and a trough positioned to receive said ,materialfrom said wiper means and to return the material to said case.

9. A spraying'apparatus comprising a rotary collecting case having open ends and agrooved surface forming an annular channel to retain a, spray-forming material, means for supplying said material thereto forspraying, means for driving said case-to cause said material to form aperipheralfilm in said channel, a centrifugal distributor comprising a freely rotatable disc mounted to dipinto saidlfilm of material andto be driven thereby, said discbeingarranged to pick up material from said film and to discharge the same centrifugally in the form of a spray in a direction to be interceptedby the rotating case, endless conveyor means comprising spaced par-v allel wires extending through said case axially to convey articles to be sprayed therethrough, said conveyor wires being mounted to return outside of saidcase.

10. In a spraying apparatus, a rotarycollecting case having open ends and a grooved surface forming an annularv channel-adapted to receive a film of spray-forming material to'be sprayed,

means for feeding said material to besprayedto said case, means for rotating said case to cause in said case and spaced around, the periphery thereof, each of said distributors comprising a distributor disc-mounted to dip into the film of material in said case and to be driven thereby, said distributor discs being positioned to pick up material from said film and to discharge. the same centrifugally in a direction transverse to the axis of said case-whereby an atomized spray zone is produced within saidLcase, and, means. forconveying an. article to be sprayed through said'spray zone.

11. Inc a spraying apparatus, a rotary collect: ing case having openends and a grooved surface forming an annular channel adapted to receive a film of spray-forming material, to be sprayed, means for feeding said material tobe sprayed to said case, means for rotating said case to cause said material to form a peripheral film in said channel, means for controllingthe rate of feed of said materialto maintain saidfilm of predetermined thickness, a plurality of distributors disposed within said case and spaced around the periphery-thereof, each of said distributors com.- prising a distributor disc mounted to dip into the means for conveying any article to be sprayed through said spray zone.

12. In a'spraying apparatusQa rotary collect-- ing case having open ends and a grooved surface forming an annular channel adapted to receive a film of spray-forming material to be sprayed, means for feeding said material to be sprayed to said case, means for rotating said case to cause said material to form a peripheral film in said channel, said feed means including a pivoted spout having an open end resting on said film, and means controlled by pivoted movement of said spout to control the rate of feed of said material to maintain said film of predetermined thickness, a plurality of distributors disposed within said case and spaced around the periphery thereof, each of said distributors comprising a distributor disc mounted to dip into the film of material in said. case and to be driven thereby, said distributor discs being positioned to pick up material from said film and to discharge the same centrifugally in a direction transverse to the axis of said case whereby an atomized spray zone is produced within said case, and means for conveying an article to be sprayed through said spray zone.

13. A spraying apparatus comprising a rotary collecting case having an open end and a grooved surface forming an annular channel to retain a spray-forming material, a spray distributor mounted in said case to project a spray of said material in a direction to be intercepted by said collecting case and to form a spray zone within said case adapted to spray an object therein,

said case, means feeding an object to be sprayed axially through the open end of said case into said spray zone, means driving said case at a rate to cause the intercepted material to form centrifugally a peripheral layer in said channel, and means returning said material from said layer to said spray distributor for re-spraying.

15. A spraying apparatus comprising a rotary collecting case having an open end through which an article may be inserted for spraying and a grooved surface forming an annular channel to retain a spray-forming material, a spray distributor carrying said material and positioned within said case to project a spray of said material in a direction to be intercepted by said case and to form a spray zone substantially entirely within said case, and means driving said case at a rate to cause the intercepted material to form centrifugally a peripheral layer in said channel.

16. A spraying apparatus comprising a rotory collecting case having an open end through which an article may be inserted for spraying and a grooved surface forming an annular channel to retain a spray-forming material, means driving said case at a rate to cause said material to form centrifugally a peripheral layer in said channel, a spray distributor carrying said material and positioned within said case to project a spray of said material in a direction to be intercepted by said collecting case and to form a spray zone substantially entirely within said case, and a stationary bafiie restricting the open area of said open end to confine said spray.

17. A spraying apparatus comprising a rotary collecting case having an open end and an inwardly grooved surface forming an annular channel to retain a spray-forming material, means driving said case at a rate to cause said material to form centrifugally a peripheral layer in said channel, and freely rotatable means comprising a centrifugal distributor having a rotatable disc, said freely rotatable means being mounted to pick up said material from said peripheral layer in said case and project such material as a spray to form a spray zone substantially entirely within said case adapted to spray an object therein.

EDWARD O. NORRIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,861,475 Hopkins et a1 June 7, 1932 1,957,791 McManis May 8, 1934 1,992,997 Drake Mar. 5, 1935 2,044,778 Halstead June 23, 1936 2,314,329 Ericson Mar. 23, 1943