US1840495A - Heat exchange device - Google Patents

Description

Jan 12, 1932. H. FELDMEIER ET AL HEAT EXCHANGE DEV I CE 2 SheetsSheet 1 Filed Jan. 28, 1930 /4 TTGYA E 7 6.

Janv 12, 1932. H. FELDMEIER ET AL HEAT EXCHANGE DEVICE Filed Jan. 28, 1930 2 Sheets-Sheet 2 Patented Jan. 12, 1932 UNITED STATES PATENT OFFICE HARVEY FELDMEIER, OF LITTLE FALLS, NEW YORK, AND LOUIS ROSENFELD, OF BALTI- MORE, MARYLAND, ASSIGINORS TO CHERRY-BURRELL CORPORATION, OF LITTLE FALLS, NEW YORK HEAT EXCHANGE DEVICE Application filed January 28, 1930. Serial No. 423,947.

This invention relates to improvements in heat exchange devices and more particularly to improvements in that type of coolers or heaters for liquids such as milk, which comprise a plurality of parallel tubes which are joined at their ends to a header or headers so that milk or other liquid in contact with the outer surfaces of the tubes can be cooled or heated by a cooling or heating liquid or medium circulated through the tubes.

Tubes attached to cast metal headers are common in heat exchange devices of this sort, but these cast headers are bulky, unsightly and heavy and are objectionable for these and other reasons. Stamped or pressed sheet meta1 headers have also been used in devices of this nature but the sheet metal headers, as heretofore made, have not been of a construction which is desirable for use in heaters or coolers for liquids such as milk, in which it is of great importance to obviate all seams, joints, crevices or other places where the milk or other material can lodge and accumulate so that the devices can be readily and thoroughly cleansed and kept always in a perfectly sanitary condition.

It is an object of our invention to provide an eflicient and desirable heat exchange device adapted for use as a milk cooler or heater, which is of a novel, simple and practical construction; which provides smooth passages in the header connecting with the tubes so as to insure smooth and efficient flow of the medium through the tubes; which is of light weight but strong and durable and provides good support for the tubes; which is of a sanitary construction providing smooth, unbroken surfaces free from shoulders, joints or crevices, for the flow of milk or liquid being treated; which insures perfect joints which will not leak and will ef fectually prevent contamination of the liquid being treated by the heating or cooling medium; also to provide a heat exchange device of the sort mentioned which is of neat and attractive appearance and has unbroken surfaces at both the inner and outer sides of the header.

Another object of the invention is to provide an efficient and desirable heat exchange device having the other advantages hereinafter described and having the novel features set forth in the claims.

In the accompanying drawings:

Fig. 1 is a front elevation of a surface milk cooler or heater illustrating one embodiment of the invention.

Fig. 2 is a side elevation, on an enlarged scale, of a part of one of the headers of the cooler or heater, showing portions of two tubes joined thereto.

Fig. 3 is an inner face view, partly in section, of the parts shown in Fig. 2.

Fig. 4 is a fragmentary, longitudinal section of a portion of one of the headers and the tubes connected thereto, taken on line H, Fig. 3, but on a larger scale.

Fig. 5 is a transverse section thereof on line 55, Fig. 4.

Fig. 6 is a fragmentary, perspective view of a portion of one of the headers and the adjacent parts of the tubes joined thereto.

Figs. 7 and 8 are transverse sections illustrating two other embodiments of the invention, in each of which the header of the device is formed from a single embossed metal sheet or blank.

In the constructions illustrated in the drawings, the heat exchange device comprises a plurality of tubes 10 arranged parallel with each other, one above the other, and connected at their opposite ends to headers 11 and 12 which provide return passages that join the tubes end to end in series so as to form a continuous coil or passage for the flow of a medium which may enter the first tube througl a pipe or connection 13 at one end thereof, a d after flowing through the several tubes in succession, may discharge from the last tube through a suitable dis charge pipe or connection 14. The tubes 10 are preferably thin walled tubes of copper or other metal of high heat conductivity which will give a rapid exchange of heat between the medium flowin through the tubes and that contacting with their outer surfaces.

Each header comprises an inner wall or tube plat: provided with holes 16 surrounded by projecting lips or flanges 17 to which the ends of the tubes are secured, and

an outer wall 18 which is formed with integral, outwardly projecting hollow bosses 19 which provide the return passages 20, each of which joins two of the tubes through the flanged tube holes in the inner member 15. The header may be made from sheet copper or other metal of suitable conductivity, stamped or otherwise embossed into the form shown, to provide the bosses 19 and the tube attaching flanges 17, and the header may be composed of separate-piece walls or members 15 and 18 joined together as shown in Figs. 1-6, or it may be formed from a single embossed metal sheet as shown in Figs. 7 and 8.

In the two-piece construction, Figs. 1-6, the two members 15 and 18 of the header are secured together by lock seams formed by the bending of the longitudinal edges 21 of the outer member 18 over the longitudinal edges of the tube plate member 15. When the two header members are thus secured together, the two members will contact or be close together, face to face, between and around the margins of the bosses 19 of the outer member.

Preferably the hole flan es 17 of the tube plateproject outwardly an% fit closely in the ends of the tubes 10 and the joints between the two parts of the header and between the hole flanges 17 and the tubes are soldered so as to securely connect the parts and provide leak-tight joints between them. Thus the joints 22 between the opposite longitudinal edgeportions of the two header members and the joints 23 between the abutting flat portions of the inner and outer members of the header, which joints 23 surround the bosses 19, are filled and sealed by solder. Each boss and the two flanged holes which are connected by the boss thus form a smooth fluid-tight return bend or passage connecting the adjacent ends of two tubes.

After the two parts of the header have been secured together by folding or bending the longitudinal edges 21 of the outer member over the edges of the inner member, the joints between the parts can be conveniently soldered by dipping 'the header in molten solder, which sweats into and seals the joints and at the same time tins or coats the surfaces of the header. Thereafter the tubes are placed in connection with the attaching flanges 17 on the tube plate and while the tubes are suitably held in place on the header, solder is floated or applied over the surface of the inner side of the header and around the ends of the tubes so as to fill the spaces between the inbent edges 21 of the outer member of the header and the tubes and form smooth, unbroken surfaces 24 which preferably extend from the inbent edges 21 and slope toward and merge into the cylindrical surfaces of the tubes, The solder fills in the depressions between the edges of the header and the tubes and leaves no crevices or pockets in which milk or other material can lodge and become foul, and because of the smooth, unbroken surfaces 24 free from crevices, cavities or pockets, the surfaces of the coo er can be readily kept in a perfectly clean and thoroughly sanitary condition.

In each of the modifications illustrated in Figs. 7 and 8, the header is formed from a single, integral metal sheet or blank. As shown in Fig. 7, the opposite edge portions of the single sheet are folded toward each other on the lines 25 at the opposite edges of the header, and the edges of the sheet meet or abut at the joint 26 in the middle of the header, the tube flanges 17 being formed half in each of the abutting edges of the sheet, while the bosses 19 are formed in the middle portion of the sheet or blank. In the Fig. 8 construction, the single header sheet or blank is folded at its middle on the line 27 at one edge of the header and the opposite edges of the sheet meet and are joined at 28 at the opposite edge of the header the tube flanges 17 and bosses 19 in this case being formed in the portions of the sheet at opposite sides of the folding line 27. The headers shown in Figs. 7 and 8 except for their single-piece construction, are substantially the same as first described, and it will be understood that the joints between the walls or portions of the header and between the header and the tubes are filled and connected by solder, as in the first described. constructions. Solder is also preferably applied at the inner side of the header to form the smooth, unbroken surfaces 24 joining and merging into the innerside surface of the header and the surfaces of the tubes, as before explained.

It will be noted that by reason of the relative arrangement and form of the parts as explained, with the integral bosses having smooth rounded surfaces at the outerside of the header and the solder fillets between the parts of the header and between the tubes and the header at the inner side of the header both the inner and outer sides of the header present smooth, unbroken surfaces, free from crevices, joints or cavities. This not only insures a sanitary construction but produces a very neat appearance, giving the impression that the device is made of a single integral piece, free from joints or connections. In the use of the described device, the milk or liquid to be cooled or heated can be caused to flow as films down over the outer surfaces of the tubes, in which case suitable means such as are usual in surface coolers and heaters are provided for delivering the liquid to the top-most tube, and for catching the liquid flowing off of the bottom tube. But the device can also be utilized in other Ways, as for instance, by immersing it in a body of milk or other liquid to be cooled or heated.

The device is preferably made with the usual tube spacing and liquid directing strips 30 between the tubes and soldered thereto.

These strips cause a more even distribution of the films of liquid over the front and back surfaces of the tubes when the device is used as asurface cooler or heater.

We-claim as our invention: 1. A heat exchange device comprising a plurality of tubes, and a header to which the tubes are connected, said header comprising an inner wall to which the tubes are attached and which has holes registering with said tubes, and an outer pressed sheet metal wall joined to the inner wall and having a plurality of integral outwardly projecting hollow bosses thereon pressed out from said sheet metal of the wall, each forming a passage communicating with two adjacent tubes through the holes in said inner wall, and

solder filling and concealing the joints between said header walls and between the header and said tubes.

2. A heat exchange device comprising a plurality of tubes, and a header to which the tubes are connected, said header comprising an innerand an outer member, said inner member having holes therein surrounded by projecting flanges to which said tubes are attached, and said outer member being of embossed metal and having integral outwardly projecting hollow bosses, each forming a passage communicating with adjacent tubes through the holes in said inner member, said outer member having edge portions bent over the edges of the inner member to secure said members together, and the joints between the two header members and between the tubes and the header being filled and concealed by solder.

3. In a heat exchange device comprising a header composed of sheet metal inner and outer members secured together by edges of the outer member folded over edges of the inner member, said inner member having holes therein surrounded by projecting tube attaching flanges, and said outer member having outwardly projecting integral hollow bosses each forming a passage connecting with adjacent holes in said inner member, the outer member being secured to the inner member by joints surrounding each of said in said first wall, said walls joining each other around each of said bosses, tubes joined to said flanges of the first wall and registering with said holes therein, and metal covering and concealing the joints between said tubes and said header and forming a smooth unbroken surface which is hermetically joined to and merges into the surfaces of said tubes and the surface of said header which faces said tubes.

5. A heat exchange device comprising a plurality of tubes, and a header which connects said tubes, said header comprising an inner member having holes therethrough surrounded by projecting flanges to which said tubes are attached, and said outer member having integral outwardly projecting hollow bosses each forming a passage communicating with adjacent tubes through the holes in said inner member, said header members being secured together by edge portions of the outer member bent over edges of said inner member at the side thereof facing said tubes, and solder concealing the joints between said header members and between the tubes and the header and extending from said bent edge portions of the outer header member to the tubes and filling the cavity between said bent edge portions and the surfaces of said tubes.

6. A heat exchange device comprising a plurality of tubes and a header which connects said tubes, said header comprising inner and outer sheet metal members, said inner member having holes therethrough surrounded by outwardly projecting -flanges on which said tubes are secured, and said outer member having integral outwardly projecting hollow bosses each forming a passage communicating with adjacent tubes through the holes in said inner member, said outer member being secured to said inner member by edge portions of the outer member bent over edges of the inner member at the side thereof facing said tubes, and said inner and outer members being soldered together at joints surrounding each of said bosses, and

solder extending from said inbent edge portions of the outer member to said tubes and concealing the joints between the header members and between the tubes and the header.

HARVEY FELDMEIER. LOUIS ROSENFELD.

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