US1857721A - Cooling apparatus - Google Patents

Description

May 10, 1932. B. J HALL COOLING APPARATUS Filed Aug. '25, 1930 Patented May 10, 1932 'BENJAMiN JAMES newt, oa -Lennon, ENG ND COOLING APPARATUS This invention relates to a means for cooling-and maintaining ina cool condition surfacessuch as those used in duplicating or printing processes and for :otherpurposes. a

:55 In the production and manipulation of gelatinerand -other colloidal films or layers for;photoemechanical and like duplicating processes it is found thatthe temperature of the workingsurface of the :film or layer must 30 hemaintained lowerthan the :particulartemperature at'which the colloid employed becomestacky. lVith a viewzto maintaining the working surface at theanecessary low tem .peratu-re iitl-has been proposed toreduce the 615 temperature cilia room in which the process is carried .-out, and it has already been proposed ;as:- an alternative to reducing the temperature'of the-roomwa-sa whole to distributewthe oolloidaltfilm or layer upon a metal i210 plate or -sh-eetxlwhich rests upon ice or cold water'orother cooling medium; Bothof these methods, however, have-serious drawg hacks, for when ;a.-I?oom;is-c001ed Jay the admission 1of;cold-airthisresults in the rapid absorptionkof: moisture from the working surface -of.--the:colloidal layer, which {renders ,the surfaceineffective for satisfactory dupli- V catingworlcopying, despite the fact that the temperature thereof is maintained at the nec- 3 essary low level. In a case wherethe colloidal layer iissdepesited npon a metal plate in contact With .ice or -water the quantity of cooling inaterial employed is unavoidably 'much greater than the :minimumiquantity which would bringTa'bout the-necessarylow temper- :ature. Moreover, the -surface area of the ,plateris much restricted and such installation :is to all-intents-iand purposes immobile.

T-he present.invention-has for an iobject to, rov-ide improved 111163113 for :theqrapid coo ing of surfaces and for maintaining them ata lower temperature =than-thewsu-rrounding atmosphere-without-said sun-faces themselves coming \into -direct-contact with the primary coolingmedium, of which latter a minimum quantity (is-employed.- According to the ;present invention means foimcoolingandmaintaining cool a; surface comprise 5311- endless ductfor the passage of 59 air, "the, outer facecofwapart of-the wall of said duct.

W Application filed:Aug-ust'25, 1'930,Seria1-1 1'o. 477,684, :an'd in GreaLBr-itain irune26, 1980, j

which duct constitutes a surface to becooled, means for producing aflow of air around said. duct, and a container forcooling medium located in the] path of airfloWingarounfd V Preferably, that part of the wall of lhe duct the outer face of. which constitutes a surface to be cooled is disposed suhstane tially horizontally, whilst the'duct 'itsel'f,.'.is disposedgtherebeneath and is such that air 60 flowing "l continuously therearoundf passes through the coolingmedium, alongthe-underside of said part of the duct wall from, end

toend, then in-areverse directionhack tothe ycoolino';n1ediu1n,.and'soon. i y

In the application .of the. 'vmprov ed means accordingto the invention for the .PIOdl1C-, ti'onlandmanipu'lation of gelatineand other colloidal 'filins or layers forphotmmec'hanical and like' duplicating processes, that part of the-wall of the ,ductfthe outer faceof which constitutes, a surface to he cooled .is preferably disposed, horizontally and is adapted ,to constitute a support for the horizontal part of ,anendless'rband on. whichethere is de posited a layer ;of colloidal material which it is required to maintain ,at" a temperature vlowerithan that ofzthe ambient atmosphere.

Preferablyyin such a caseflthe duot isiof substantially triangular formation and ,is so shaped. as a; wholel so asito fitiwithin the-space enclosed hyra .continuous hand which travels around three horizontal rollers, so disposed that theband travels-for, a short distanceiven tically, then horizontally fora considerable distance, and thendownwardly at an angle, 'l"lie duct is preferably, arranged so ,thatgthe bandisvincontactwith the outerwwall ,thereof whilst travelling horizontally and Lalso whilst travelling downwardly at ,an.angle. The means for producing V a flow; of {air around the ,duct may comprise one or gmore fans mounted withimtheduct near that roller from which i the hand I travels) horizontally, whilstthereisalso mounted intheg-ducuhejlow said fans one or more containers forricefor other coo-linginediu n,through which the air Y can .pass from the downwardly inclined {portion'of the-duct'.on-its way to the faniqrp flns. I

,The invention is illustratedgbyltliezgaccom- $1.

' panying drawing, the figure representing a ly'inclined wall 17, so that the linoleum band 11 which is in contact with said walls 16 and diagrammatic longitudinal section of the apparatus.

' As shown, the improved means are fitted to an apparatus of known type comprising a casing 1 in which an endless band 11 of linoleum or the like, which has deposited thereon a layer of gelatine or other colloidal mate-.

rial in known manner, is mounted to travel over three rollers 12, 18' and 14, the arrangement being such that although the whole surface of the band 11 is employed for duplicating purposes, very little space is occupied, whilst any part of the band may readily-be made accessible by rotating one of the rollers 12, 13 or 14: by hand to bring that part of the hand between the rollers 12 and 13. In the ordinary way this particular part of theband would be supported upon a table or upon a plate resting upon ice or other cooling medium; according to the present invention, however, the substantially triangular space enclosed by the band 11 is occupied by a continuous duct 15 for air, the improved means according to the present invention being emp'loyed for cooling the upper horizontal wall 16 of the duct and also the lower downward- 17 and the gelatine or' other colloidal material deposited thereon are maintained at the" closed by a' partition'EZO, whilst thespace 21 enclosed by the inner walls 22 is left vacant.

The fan or fans 19 are such that when in operation air is caused to flow around the duct in the direction shown by the arrows,

. passing from the containers 18 for the cooling medium to fans along the horizontal part of theduct and back along the downwardly inclined part of the duct to said containers 18. It will be observed that with such an arrangement according to the invention a minimum of cooling materlal is required to maintain the surface at the necessary low temperature, for as the duct 15 is entirely en' closed the air passing to the cooling medium will be already at a temperature considerably I low-er than that of the ambient atmosphere.

Thus, it will be observed that waste of the cooling medium employed is reduced so far as possible consistent with the necessary absorption of heat from tained cool. I V I r Theuse of an apparatussuch as that de- Lscribed above. with reference to the accompanying drawing is applicable particularly to those tables designed for use in the prepathe surface to be main-' =that-the duct may containbaffles or filters in order that eddying flow'may be produced, so causing an increased cooling effect, whilst in some cases it may be desirable to provide a breather or safety valve to prevent undue pressure within the duct or ducts. For example, valves may be provided whereby said pressure may be maintained in any desired manner, and those parts 'of'the duct, except that which constitutes a surface tobe cooled or which is in contactwith the surface to be cooled, maybe enclosed by insulating mate rial to prevent the absorption of heat thereby.

What I claim is w f 1. An apparatus of the class described, comprising a casing formed with an endless duct open to the'atmosphere at one end, roll ers mounted outside the casing to receive a band of material to be treated, peripheries of the rollers being in a plane with the outer surfaces of the top and bottom of the casing, and means in the openend of the casing for introducing coolair to the endless duct to reduce the temperature of the top and bottom of the casing, whereby the contacting surfaces of a belt passing aroundthe rollers are cooled. p 2. An apparatus of the class described, comprising a casing formed with an air passage,of means for guidinga flat strip of material over the outer surface of the Wall forming the passage, a container in the casing for a cooling medium for cooling the air, and means for forcing the cooled air through the passage, whereby the surface of a flat strip of 7 material passing over the outer wall of the passage is'coole v r,

3. An apparatus of the class described, comprising a casing having a' horizontal top and a bottom which inclines from! one end of the casing to the other, said casing being 0 en at its wide end, a continuous duct formed 1n the casing-means for introducing cool air to the duct, and means on the outsideof the casing for supporting a band of material to be cooled in contact with the outer surface of the horizontal and inclined surfaces of said cas- 4. An apparatus lar" form, a continuous duct formedin the caslng, means for forcing cool air through r of the class described, comprising a casing of substantially trianguthe duct, rollers mounted outside the casing to V i receive aband of material to betreated, one

of said rollers being mounted'at the apex-of the casing and two ,of said rollers beingfl mounted at the larger end of the casing, the

-peripheries of all the rollers being in alignment with the top and bottom outer surfaces of the casing to retain the material being treated in contact with said surfaces to be 5 cooled by the cool air passing-through the duct.

BENJAMIN JAMES HALL.

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