US2348224A - Coating machine - Google Patents

Description

y 1944- N. PELOSI 2,348,224

- COATING MACHINE Filed Aug. 22, 1940 2 Shets-Sheet 1 INV ENT OR.

BY Q

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ATTOENEYS y 1944- N. PELOSI 2,348,224

COATING MACHINE Filed Aug. 22, 1940 2 Sheets-Sheet 2 INVENTOR BY@ 0 a /wam TTOENEYS Patented May 9, 1944 COATING MACHINE Nicholas Pelosi, Newark, N. 1., assignor to American Can Company, New York, N. Y., a corporation of New Jersey Application August 22, 1940, Serial No. 353,772

2 Claims.

The present invention relates to coating machines and the like for applying a coating such as paraffin wax to the surfaces of fibre containers and has particular reference to delaying the setting and hardening of the applied coating so that it will be prevented from accumulating on parts of the machine which handle the coated container.

In the manufacture of coated fibre milk containers of the character disclosed in United States Patent 2,085,979, issued July 6, 1937, to J. M. Hothersall, the container is preferably immersed in a bath of molten paraflln wax so that the entire inside and outside surfaces of the container are thoroughly covered. After such a coating operation the excess wax is preferably drained away and the container is then conveyed into a chilling chamber to set and harden the applied coating.

For best results the conveyor that carries the coated container through the chilling chamber is preferably a, separate conveyor which has no connection with a similar conveyor that carries the container through the hot bath of paraflin. This prevents uneven temperatures in the conveyors. Transfer of the container from the hot conveyor to the cold conveyor is preferably made by way of a transfer turret disposed at the entrance of the chilling chamber and this turret is subject to a cold blast which issues from the chilling chamber. Thus the coating on the containers begins to set prematurely while in the transfer turret and hence some of the coating material sticks to the turret and builds up to such an extent that there is interference with the proper registration of the container in the turret.

The instant invention contemplates overcoming this difficulty by heating the transfer turret so that the chilling action on the containers is delayed until the containers are free of the turret. This maintains the applied coating in a liquid state especially where it engages the turret and thus prevents it from building up on the turret.

An object therefore of the invention is the chine wherein the conveyor devices are constructed so that a heating medium may be circulated through them and thus maintain the devices in a heated condition to prevent the coating material from adhering thereto.

Numerous other objects and advantages of the invention will be apparent as it'is better understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

Figure 1 is a top plan sectional view of a portion of a coating machine embodying the instant invention, with parts broken away;

Fig. 2 is a longitudinal section taken substantially along the line 2-2 in Fig. l, with parts broken away; and

Fig. 3 is a transverse section taken substantially along the broken line 3-3 in Fig. 1, with parts broken away. I

As a preferred embodiment of the instant invention the drawings illustrate principal parts of a coating machine in which rectangular fibre containers A are adapted to be coated interiorly and exteriorly with molten paraflln wax as hereinbefore explained.

The containers A preferably enter the machine in a horizontal position and are picked up by an endless chain coating conveyor H (Figs. 1, 2 and 3) having pockets l2 which extend transversely of the conveyor and in which the. containers may be rocked as they move with the conveyor. Guide rails l3 disposed along the path of travel of the conveyor hold the containers in the conveyor pockets.

The conveyor operates over a pair of spaced sprockets l5, only one of which is shown in the drawings. These sprockets are located. adjacent the ends of the machinezand are mounted on transverse shafts l6 carried in suitable bearings formed in a frame H which constitutes the main frame of the machine. These shafts may be rotated in any suitable manner in time with the other moving parts of the machine.

The conveyor I l first propels the entering containers A along its lower run and carries them down into and through a bath of the molten paraflln wax contained in a tank or reservoir-2|. This tank is located directly under the conveyor and is secured to the main frame ll. It is in this bath that the containers are immersed to re ceive their coating of wax.

After immersion the containers are carried by the conveyor upwardly out of the bath and around the companion sprocket l5, not shown, and are which has just been applied thereto.

thereupon propelled toward the entrance end of the machine along the upper run of the conveyor. While traveling alongthis run, the containers are rocked to drain them of the excess paramn and are then turned into an upright position as shown in Fig. 1. This turning and rocking of the containers is performed by appropriately located twisted portions formed in the guide rails 13.

The tank 2| and the section of the machine through which the containers have just passed is maintained in a heated condition in any suitable manner so that the coating material in the tank and on the containers will remain in a liquid condition for proper application and draining.

Adjacent the heated section of the machine there is a cooling or chilling chamber 23 (Figs. 1 and 3) which extends rearwardly along the heated section and which is insulated therefrom to prevent heat transfer. This chamber contains an endless auxiliary chain or cooling conveyor 24 which is disposed in a horizontal position and whichoperates over spaced sprockets 25 mounted on vertical shafts 26 carried in bearings 21 formed in the main frame l1. Only the sprocket at the entrance end of the machine is shown in the drawings. The shafts 26 may be rotated in any suitable manner in time with the other moving parts of the machine.

The cooling conveyor 24 propels the coated and drained containers A through the chilling chamber 23 to set and harden the wax coating For this purpose the conveyor carries a plurality of container supporting and carrying racks 3| which are spaced at intervals along the conveyor. These racks are formed to hold the container in an upright position. Guide rails 32 disposed adjacent the path of travel of the conveyor retain the container in position in the container racks.

Transfer of the coated and drained containers A from the coating conveyor II to the cooling conveyor 24 is preferably effected by a rotating turret 35 (Figs. 1 and 3) which is disposed between the conveyors adjacent the entrance end of the machine and outside of the chilling chamber 23 and the heated section or coating reservoir of the machine. The turret is formed with spaced pockets 36 arranged around its outer periphery for propelling the containers along a curved path of travel. Curved guide rails 31 disposed adjacent the path of travel of the containers retain them in the turret pockets.

The transfer turret 35 is mounted on a vertical shaft 4| which is journaled in upper and lower bearings 42'formedin the main frame IT. The shaft is rotated in any suitable manner in time with the other moving parts of the machine.

In order to prevent the cool air which issues from the chilling chamber 23 from prematurely setting the wax on the containers while they are in the transfer turret, the latter is maintained in a heated condition as hereinbefore explained. For this purpose the turret is formed with a hollow casing 45 which encloses a chamber 46 through which a heating medium such as steam, hot oil, hot water or the like may .be'

circulated.

Circulation of the heating medium through the turret is preferably effected by way of an inlet and an outlet pipe. The inlet pipe, marked 41, is threaded into the upper end of the turret shaft 4| and leads from any suitable source of heating medium. The machine end of the pipe communicates with a passageway 43 formed in the turret shaft and this passageway is connected with the turret chamber 48 by a short angularly disposed ,port 49 formed in the hub of the turret. Thus the heating medium passes directly into the heating chamber to maintain the same at a desired temperature.

The spent. heating medium returns from the turret chamber 43. by way of an outlet port 5| which is formed in the hub of the turret. This port connects with a return passageway 52 in the shaft 4|. The passageway extends to the lower end of the shaft and there communicates with the outlet pipe, designated by the numeral 53, threaded into this end of the shaft. The outlet pipe may lead to any suitable place of deposit for the spent heating medium or the same may be recirculated, if desired.

Thus the heating medium circulating through the turret chamber 46 maintains the turret 35 in a heated condition and any of the wax coating on the container which adheres to the turret while the container is in a turret pocket 36 is quickly melted and drains away from the turret. It is this melting action that prevents the coating material from building up on the turret ad- Jacent its pockets. This maintains the pockets in condition for the reception and proper holding of the containers while being transferred from the coating conveyor to the cooling conveyor.

It is thought that the invention and many of it attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

1. A device for transferring freshly coated articles from a heated coating unit to a cooling unit, comprising a rotary turret disposed so as to be partially exposed to the temperatures oi each of said units, said turret having peripheral pockets thereon for receiving the coated articles to be transferred from one unit to the other, and means for directly heating said turret for maintaining the temperature of said pockets above the'melting temperature of the coating, whereby to prevent said coating on the articles from being chilled and accumulating within said turret pockets.

' 2. A device for transferring freshly coated containers from a wax coating chamber to a chilling chamber, comprising a rotatable turret disposed so as to be partially exposed to the tem peratures of each of said chambers, said turret having a plurality of peripherally spaced pockets for receiving the wax coated containers to be transferred and an interior chamber, and means for circulating a. heating medium through said chamber for maintaining the temperature of said pockets above the melting temperature of the wax coating, whereby to prevent said coating on the containers from being chilled an accumulating on the turret and within said turret pockets.

NICHOLAS PELOSI.

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