US2874949A

US2874949A - Brazing furnace construction

Info

Publication number: US2874949A
Application number: US393363A
Authority: US
Inventors: Clyde W Morrison
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-11-20
Filing date: 1953-11-20
Publication date: 1959-02-24
Anticipated expiration: 1976-02-24

Description

- Feb; 24, 1959 Filed Npv. 20, 1953 c. w. MORRISON 2,874,949

BRAZING FURNACE CONSTRUCTION 2 Sheets-Sheet l Fig.2

IN VEN TOR.

: CLYDE 14 MOQR/SO/V ATTORNEY v Feb. 24, 1959 c, w MORRISON 2,874,949

BRAZING FURNACE CONSTRUCTION Filed Nov. 20, 1955 *2 Sheets-Sheet 2 uQ-A 19 L '23??? -f; :"r

IN VEN TOR.

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ATTORNEY United States Patent-Of BRAZING FURNACE CONSTRUCTION Clyde W. Morrison, La Salle, Mich.

Application November 20,1953, Serial No. 393,363 8 Claims. (Cl. 263-40) This invention relates to high temperature furnaces, but particularly to hydrogen brazing furnaces.

Ordinarily furnaces of this type are constructed of masonry, insulating fire brick' being used for the walls.

of the heating chamber. In the event of damage, breakage or fracturing of the walls of the heating chamber, it is necessary for the furnace to be shut down for quite a long period of time sufiicient to allow cooling to a degree enabling the damaged portion to be repaired,- such as the replacement of the insulating brick by properly cementing them in place after removal of the damaged ones. Not only is this costly from the repair standpoint, but the extended time during which the furnace is out of operation is even more costly.

It is a desideratum to obviate the above difficulties and objections and to produce a furnace, the parts of which are subject to fracture, are readily accessible and can be quickly replaced without the necessity of cementing fire brick or taking the time to cool down the furnace as has heretofore been imperative.

Another object is to produce a furnace of the above type having the novel features of construction and arrangement hereinafter described.

Other objects and advantages of the invention will hereinafter appear, and for purposes of illustration but not of limitation, an embodiment of the invention is shown on the accompanying drawings, in which:

Figure 1 is a transverse sectional view on the line 1-1 of Figure 2, showing the furnace, a portion of the metal plate being broken awayfon purposes of clarity and the wire mesh chain conveyor for progressing articles through the heating chamber being omitted;

Figure 2 is a vertical sectional elevation substantially on the line 2-2 of Figure l and diagrammatically showing the wire mesh chain conveyor with drive wheel on the outside of the furnace; and

Figure 3 is an enlarged perspective view of one of the blocks forming the side walls of the heating chamber and showing fragments of the transverse bars socketed in the block as well as tubes supported on the top of the blocks.

The illustrated embodiment of the invention comprises a hydrogen brazing furnace having a sheet metal shell of substantially rectangular form. The top of the shell is open but is closed by a sheet metal cover 13. The bottom of the shell is closed by a plate 11 which rests upon a pair of U beams 12 thereby elevating the furnace from the supporting floor. Within the shell and resting upon the sheet metal bottom wall 11 are a number of courses of insulating fire brick suitably cemented together forming a masonry structure indicated at 14. Supported on the masonry structure 14 are two vertical walls of cemented refractory blocks 15 which are spaced laterally from each other and which terminate a substantial distance short of the sheet metal cover 13.

Disposed between the upright masonry walls 15 and the side walls of the shell 10 is a quantity of suitable loose insulating material 16, substantially filling the space to afford the proper degree of heat insulation for retaining the heat within the heating chamber and maintainoutwardly extending integral projections 20. Each projection 20 has a flat top 21 and a socket or notch 22 open at the upper end and a downwardly and inwardly tapering bottom wall 23. It will be understood that the projections 20 on the blocks of each of the two rows, face eachlother, and extending from one block to its opposite, are ceramic bars 24 of suitable ceramic supporting material, the ends of the bars resting in the 'sockets 22. Each of the bars has a fiat bottom and parallel side walls with a rounded top wall. Thus the lower series of bars 24 form the support for hearth plate and the top row of bars 24 form the support for top heating element.

Resting on the ledges 18 are the end portions of elon gate tubes 25 which are of suitable ceramic insulating or refractory material. The tubes 25 form the support for loose insulating material 26 which is placed on top,

providing a seal for the top of the heating chamber.-

Any suitable heat insulation material which can, for example, be shoveled in, is suitable for this purpose.

Thus the tubes 25 are placed close enough together so as to supportand retain the insulating material 26 in place.

From the above, of failure or damage to one or another of the blocks 17, the top 13 is removed and the insulating material 26 shoveled out and by removing the tubes 25 or a portion of them, the failure can be readily located and when located, the damaged block can be lifted out and replaced by a new one without putting the furnace out of operation for any extended period of time. Since no masonry is necessary for this purpose, the time required for effecting the repair is reduced to a minimum. Similarly access can be had to one or more of the bars 24 which had failed for one reason or another.

The entrance to the heating chamber is indicated at B, and the exit at A and in these regions different sized refractory blocks are employed and these may be freely laid in place and as shown, similar tubes 25 are disposed in this region. At the inlet blocks of ceramic refractory .material are loosely arranged to provide a flue 30 for the outlet of combustion gases or products of combustion. In this instance, a hearth plate 27 rests on the 1 lower series of bars 24, and for conveying material through the heating chamber, an endless conveyor 28 trained over suitable drive wheels 29 and driven in any suitable manner, is provided.

It is to be understood that the chamber may be heated by suitable electrical units arranged above and below the bars 24 respectively, i. e. an electrical heating unit below the lower row of bars 24 and another electrical heating unit above the upper series of bars 24. These are not illustrated nor is the means for introducing and creating the hydrogen atmosphere, since these devices are well-known to those skilled in this art and a detailed description and illustration thereof are not regarded as necessary.

From the above description, it will be manifest that the important features of the invention reside in the provision of loosely arranged removable blocks which can be replaced in the event of failure, breakage or the like without shutting down the furnace for any extensive Patented Feb. 24, 1959.

it will be manifest that in the eventperiod of time and'without employing any masonry. The tubes which support the insulation also can be replaced readily since they are simply loosely arranged and by by taking out the loose insulation arranged above the,

work since no masonry is required to effect such repairs.

It is to be understood that numerous changes in details of construction, arrangement and choice of materials may be effected without departing from the spirit of the invention especially as defined in the appended claims.

What I claim is:

l. A furnace of the "class described, comprising aplatform and upright laterally spaced fixed masonry walls of insulating refractory material having flat inside surfaces, and means forming a treating chamber between said spaced walls, said chamber forming means including a horizontal row of insulating refractory blocks of similar construction arranged contiguous to each other, said blocks being adjacent to and free from the inside of each wall, each block being loosely mounted, whereby one or more damaged blocks can be readily lifted vertically and replaced without resorting to cementing the blocks together, a row of loosely mounted independent insulating members separate from each other and spanning the upper ends of said blocks and resting freely on same, thereby to provide the ceiling for the combustion chamber, and loose insulating material covering said insulating members whereby access to one or another of the blocks is had by removing portions of the insulating material and adjacent insulating members.

'2. A furnace of the class described, comprising a base, a pair of upright laterally spaced permanent masonry walls, a row of upright blocks of insulating refractory material on the inside of each permanent wall, each block being loosely mounted and free of adjacent blocks, a loose spacer member extending transversely between corresponding blocks of each row, means on each upright block for receiving an adjacent end of a spacer member, transverse closely arranged insulating members spanning thetops of said blocks, and loose insulating material covering said transverse members, whereby removal of one or more of said blocks can be had by removing the loose insulating material and the adjacent transverse members and then lifting out the desired block or blocks.

3. A furnace as claimed in claim 2, comprising a pair of vertically spaced supporting ledges on the inner face of each block, and bars constitutingthe spacer means resting on corresponding ledges respectively, thereby to extend transversely between the spaced rows upright blocks.

4. A furnace as claimed in claim 2, in which the insulating member's comprise elongate tubes, arranged contiguously to each other.

5. A furnace of the class described comprising a base,

a pair of upright laterally spaced permanent masonry walls, a row of upright blocks of insulating refractory material on the inside of each permanent wall, each block being loosely mounted and free of adjacent blocks, each block having on the inner face thereof a pair of vertically spaced sockets open at the top, bars extending from the sockets of one block to corresponding sockets of the opposite block and having their end portions loosely resting in sockets, a row of contiguous tubes resting freely on the top of said blocks, and insulating material on said "tubes.

6. A furnace of the class described comprising a base, a pair of Upright laterally spaced permanent masonry walls, a row of upright blocks of refractory material on the inside of each permanent wall, each block being loosely mounted and free of adjacent blocks, each block having on the inner face thereof a pair of vertically spaced sockets open at the top, bars extending from the sockets of one block to corresponding sockets of the opposite block and having their end portions loosely resting'in sockets, and cover means extending from one row 'of upright blocks to the other end loosely resting on the top portion of such blocks.

7. A furnace of the class described comprising a base, a pair of upright laterally spaced permanent masonry walls, a row of upright blocks of refractory material on the inside of each permanent wall, each block being loosely mounted and free of adjacent blocks, each block having on the inner face thereof a pair of vertically spaced sockets open at the top, and bars extending from the sockets of one block to corresponding sockets of the opposite block and having their end portions loosely resting in sockets.

8. A furnace of the class described comprising a base, a pair of upright laterally spaced permanent masonry walls, a row of upright blocks of insulating refractory material on the inside of each permanent wall, each block being loosely mounted and free of adjacent blocks, each block having on the inner face thereof a pair of vertically spaced supports with upwardly open supporting surfaces, bars extending from the supports of one block to corresponding supports of the opposite block and having their end portions loosely resting on said supports, and cover means extending from one row of upright blocks to the other and loosely resting on the top portion of such blocks.

References Cited in the file of this .patent UNITED STATES PATENTS 1,670,606 Bowen May 22, 1928 1,741,680 Davey Dec. 31, 1929 2,552,648 Poland IMay 15, 1951 FOREIGN PATENTS 849,145 France Aug. 7, 1939 255,479 Great Britain Apr. 21, 1 927