US2274284A - Method and apparatus for treating materials - Google Patents

Description

Feb; 24, 1942.

,A METHOD AND APPARATUS FOR TREAT-ING MATERIALS Filed Sept. r5, 1940 INV/NTOR Herk?? (i. 707e Patented Feb-V24, 1942 Y Herbert G. vere, .reeksen Heights, N. Y., assigner to American Seal-Kap Corporation of Delaware, Wilmington, Del., a corporation of Dela- WIPO Appuesuen september s, i940, serial No. 355,441

(el. sli- 55) 3 Claims.

This invention relates to a method and apparatus for treating materials and more particularly to a method and apparatus for cooling waxtreated paper blanks.

This invention isan improvement onP the process for treating paper blanks to condition the same for the formation of cover-all milk bottle .caps as described in the `Baum Patent 1,668,349.

In that process the blanks are wax-treated or impregnated, stacked, and stored for seasoning or tempering to condition the same for a severe forming operation. It has been found, however,

that in order to obtain uniform impregnation and to prevent the blanks from sticking together Awhen stacked, the surface of the wax-treated blanks must be cooled at least to a temperature below themelting point of the wax before stacking. One method of accomplishing this is tohold the blanks on a conveyor for a sufficiently long time toallow the blanks to.become cooled to the desired point. 'I'his method, however, is unsatisfactory from a quantity production standpoint due to the excessive space which would be required for long conveyors of the type above indicated.

An object of the invention is to provide a novel and improved means for cooling the wax-treated blanks prior to stacking.

Another object is to provide a cooling system which is applicable to the treatment and processing of various materials.

Another object is tofprovide means for quickly and eiiiciently cooling blanks of the type above indicated, which requires onlya minimum. t amount of'plant space and equipment.

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

In accordance with the present invention, I have found that the blanks may be quickly and uniformly cooled by spraying thereon aesmall quantity of a readily vaporizable liquid such as water and utilizing the heat of the blanks to vaporize the liquid. The latent heat of vaporization 'of the vliquid thus serves to extract heat from the blanks and thereby rapidly cools the same to the desired point. A minimum amount of liquid is4 used and the major part of the liquid is immediately evaporated and removed from the blanks so as not to interfere with the subsequent operations. A predetermined amount of moisture may, if desired, be allowed to remain on the blanks for conditioning the same for the subsequent forming operations.

air from contact with the blanks and facilitates the vaporization of the water.v

'I he surfaces of the blanks are thus cooled quickly to a point such that the wax film thereon becomes solidified. The body of the blank, however, remains hot and when the blanks are stacked the stored heat serves to gradually soften the wax and causes the same to be drawn into the fibres for impregnating the blanks. The wax is not softened on the surface, however, to such an extent that the wax tends to flowand cause uneven impregnation or to cause the blanks to stick together. This latter feature is of particular importance when the wax contains adhesive mato be characteristic of this invention are pointed out more particularly inthe claims appended representation of a wax treating process embodyhereto, the invention itself,'as to its objects and advantages and the manner of its operation, may be better understood by referring to the following description, taken in connection with the accompanying drawing in which'a specific embodiment thereof has been set forth for purposes of illustration.

In the drawing, the figure is a' diagrammatic ing the present invention.

In the following description and in the claims certain specific terms are used for convenience in referring to various details of the invention. It is to be understood, however, that these terms are to be given as broad an interpretation as the state of the art will permit.

Referring to the drawing more in detail wherein the invention is applied to the treatment of a paper blank to be used for the formation of milk bottle caps in accordance with the process set forth in the Baum Patent 1,668,349 above referred to, the material is shown in the form of a web It which is supplieddfrom a roll Il. The web I0 is fed from the roll I l by suitable means not shown, to a punch or die I2 wherein the desired blanks are punched therefrom, the used web being taken up in a roll I 3. The blanks I4 which are punched from the web I0 by the die' I2 are passed by conveyors- Il and I6 through wax baths I1 and- I) respectively in tanks I9 and. The wax may I In one embodiment the wax-treated blanks are be maintained in a molten condition by any suitable heatingmeans not shown. Upper webs 2l and 22 may be provided to hold the blanks in position in the bath during the wax treatment.

The blanks Il, after removal from the tank 20, are passed between squeeze rollers 25 which are j so adjusted as to remove theexcess wax coating from the surface of the blanks and to discharge the blanks onto a conveyor 2B with a predetermined wax nlm on the surface thereof.

vaporization is thus utilized for cooling the sur-v face of the blanks as above indicated. After clncally applied to the treatment of paper blank to be used for the formation of cover-all milk bottle caps, it is to be understood that the cooling system is also applicable tovarious other processes wherein it is desired to quickly coolwebs or blanks. The invention is only to be restricted in accordance with the scope of the appended passage under the hood 28, the blanksare passed under a drying hood 32 which is supplied with a current of cold air by a fan or blower 33 actu-f ated by a motor 34.

After these blanks have thus been cooled, they are discharged into a stacking device 354 wherein they are stacked and may be removed to storage or to suitable cap forming mechanism as may be desired.

' In the operation of this system it is to be understood that water may be applied to the blanks prior to wax treatment if desired as set forth in the Baum patent above mentioned. It is also to be understood that the quantity of liquid s'upplied by the nozzles 29 andthe time of treatmentv under the hood 32 are so controlled that all of the water supplied tothe blanks is evaporated from the surface thereof or so that a portion remains thereon for conditioning the blanks as may be desired.

It has been found that an extremely small quantity of water is sufficient for the above purpose and that, when operated as above indicated, the evaporation of the water rapidly cools the surface of the blank to a point such that the wax becomes hardened and subsequent now of the wax which would produce uneven impregnation is avoided. The body of the blank, however, is not immediately cooled and the heat stored therein is sufficient to cause the wax to become absorbed into the nbres of the blank itself, as set forth in detail in the above mentioned Baum patent.

The quantity of cooling liquid is not sumcient to cool the blanks by heat absorption but is so l regulated that the latent heat of vaporization of a small quantity of readily vaporizable liquid is utilized for the purpose. -While waterhas been claims.

What is claimed is:

1. An apparatus for treating paper blanks, comprising a reservoir containing a molten wax bath, conveyor means for passing said blanks through Asaid bath, a cooling zone, conveyor means passing the wax-treated blanks from said reservoir through said cooling zone, means spraying a vaporizable liquid onto the blanks in said cooling zone in a quantity such that the heat of the blanks vaporizes at least the major part of g said liquid and a drying zone including means to supply a current of cold air over said blanks for removing said vapor, vsaid conveyor means carrying said blanks from said cooling zone through said last zone.

2. Thevprocess for preparing blanks for the formation of formed articles such as milk bottle caps, which comprises passing said blanks through a wax bath to impregnate the fibers thereof with said wax and to form a surface film of wax thereon, removing Asaidblanks from said' bath, spraying ontothe surface of said blanks a vaporizable liquid in a quantity such that the heat of the blanks vaporizes at least a major part of said liquid, passing said blanks through a drying zone and in said drying zone rapidly removing the vapor` laden air from-contact with said blanks under conditions to utilize the heat of vaporization of said liquid as a cooling agent to cool rapidly the surface of said blanks to a point such that the Wax nlm thereon solidines.

3. The process for preparing blanks for the formation of formed articles such as milk bottle caps, which comprises passing said blanks through a wax bath to impregnate the fibers thereof with said wax and to form a surface nlm of, wax thereon, removing said blanks from said bath, spraying onto the surface of said blanks a vaporizable liquid in aquantity such that the heat of the blanks vaporizesat least a major part of said liquid. passing said blanks through a drying zone and in said drying zone rapidly removing the vapor laden air from contact with i said blanks under conditions to utilize the heat found satisfactory, various other vaporizable liquids may be used if desired.

While the invention has been shown as speof vaporization of'saidliquid as a cooling agent to cool rapidly the surface of lsaid blanks to a point such that'the wax fllm thereon solidiiies while the body of the blank retains stored heat, and stacking the blanks for a sufficient time to .allow the stored heat-to soften and draw the surface nlm of wax into the .nbers for impregnating the same;

HERBERT G. VORE.

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