US1429380A

US1429380A - Continuous annealing furnace

Info

Publication number: US1429380A
Application number: US543918A
Authority: US
Inventors: Martin Van Marle
Original assignee: Individual
Current assignee: Individual
Priority date: 1922-03-15
Filing date: 1922-03-15
Publication date: 1922-09-19
Anticipated expiration: 1939-09-19

Description

M. VAN MA'RLE. CONTINUOUS ANNEALING FURNACE.

APPLICATION FILED MAR. 1511-922.

Patented Sept. 19, 1922..

2 SHEETS-SHEET 1L Q s Qw. W

M. VAN MARLE.

CONTINUOUS ANNEALIUNG. FURNACE.

APPLICATION FILED MAR. 1.5. 1922.

2 SHEEYT\SSHEET 2.'

Patented Sept. 19, 1922;

Patented Sept. 19, E922.

CONTINUOUS ANNEALING FURNACE.

Application filed March 15, 1922. Serial No. 543,918.

T 0 all whom it may concern:

Be it known that I, MARTIN V-AN MARLE, a subject of the King of Great Britain, residing at Dibdale lVorks, Dudley, in the county of orcester, England, have invented certain new and useful Improvements in and Connected with Continuous Annealin Furnaces; and I do hereby declare the fo lowing to be a full, clear, and exact description of the same.

This invention has reference to continuous annealing furnaces of the kind in which there is a retort or other heating chamber provided with water sealed ends through which the goods are passed by an endless conveyor. This heatingchamber contains steam or an inert gas so that the goods are prevented from oxidizing in any way in their passage through the same, but they leave the water seal on the outlet end perfectly bright and free from' scale. .The heating chamber is usually arranged to be heated by the combustion of producer gas and heated air in a chamber communicatin with transverse fiues around the outside 0 the heating chamber.

Heretofore in this kind of continuous annealing furnace, the endless conveyor is usually composed of several flat link chains fixed together side by side and spaced apart by cross bars at the joints and together forming a conveyor of the required width.

on WhlCll the goods are carried. These chains ass slowly over sprocket wheels beyond t e inlet and outlet tanks. are suitably guided and return underneath the heating chamber. They are adapted to pass down into a water tank at the inlet end and carry the goods up and out of the tank into and through the hood and inlet mouth into and along the heating chamber. The goods are conveyed out of the heatingchainber.

at the outlet mouthand down through the open bottom of the hood into the cooling water tank from which the goods are removed by an attendant. From this point theconveyor chains rise and pass over the sprocket wheels to return underneath the furnace as aforesaid.

Hertofore it has been customary for the sprocket wheels which are fixed side by side on a driven shaft at the forward end to pull the chains and goods through the heatin chamber. The chains are held down in the tanks or in the cooling tank by means of edge rollers fixed on" pins projecting from the sides of the cooling tank and under which the conveyor chains pass, spaces being left between the rollers to clear the goods on the chains. It is found in practice that the chains in course of a short time. stretch and have to be shortened and ultimately become stretched to such an extent that they will no longer gear with the sprocket wheels and then they have to be discarded for new chains. i

The object of the present invention is to overcome the defect and to provide an improved and'simplified arrangement which will reduce the tensile strain on the endless conveyor chains and enable them to last with a minimum of stretch for a considerablylonger time than at present.

According to this invention, the, furnace is provided with a conveyor which hangs in one or Imore loops and which is positively driven at the same speed at both ends to maintain the loops and thereby carry the goods through the quenching fluid on its way to and from. the heating chamber.

It has been proposed to drive the conveyor chains of a tempering machine at the same speed at both ends but in this case the conveyor was flat from one end to the other.

Referring to the drawings F igure 1 is asectional elevation of a furnace according to this invention.

Figure 2 is a plan view thereof.

Figure 3 is a detail elevation of means to control the speed of travel of the conveyor chain showing the same in one position.

Figure 4 is a similar View of the control means at the opposite end of the furnace.

In the'construction illustrated upon the accompanying drawings, the furnace ineludes the usual tank 1' adapted to hold the inlet end to receivethe goods and carry them into and through the heating chamber,' and atthe outlet end to deliver the goods from the heating chamber into the cooling tank.

The usual edge rollers-to keep the chains down in the tank are now not required and are dispensed with. Thus, as all these four sets of sprocket wheels are positively driven, and each set has only'to drive a short section of the complete conveyor, it follows that the tensile strains, on the conveyor chains are very considerably reduced.

Moreover, by sectionally driving and supporting the conveyor chains by several sets of sprocket wheels as aforesaid so that the stretch and wear on the conveyor chains is so-considerably reduced, it is possible to very materially increase the Width of the heating chamber and combined conveyor chains and moreover, the cross rods which have previously been employed for tying the various chains together to maintain them at the proper distances apart sideby side -can be dispensed with, as any lateral spread of the conveyor chains where they run throu hthe tanks and heating chamber is effectua ly prevented by the additional sets of sprocket Wheels which are provided as aforesaid in the water tanks under the inlet and outlet hoods.

It is to be understood that the peripheral speed of all the sprocket wheels is the same.

The two horizontal shafts 12 on which are mounted the two sets of sprocket wheels in the water tanks as aforesaid are each supported by bearings 13 fixed to the sides of the tank. One of the said bearings for each shaft is made as a stufiing box 14 through which the said shaft projects for driving,

' and this shaft has an external sprocket wheel 15 which gears with an endless chain 16 from a corresponding sprocket wheel 17 fixed on the adjacent sprocket wheel shaft 18 beyond the tank. The two end sprocket wheel shafts outside the tank are simultaneously driven preferably from a first motion shaft 19 near one of the end tanks. This shaft is preferably fitted with a coned pulley 20.and driven from a similar coned pule ley on a driving shaft, not shown, so as to run the conveyor cha1n at varlous speeds.

wheel shaft 18 is driven from this counter shaft by another pinion 31 gearing into a spur wheel 32 on the sprocket wheel shaft so that by this mechanism a slow intermittent rotary motion is transmitted from the first 6t} motion shaft to the end sprocket wheel shaft messed 18, and also to the shaft'12 in the water tanls by means of the sprocket wheel 17, endless chain 16, and sprocket wheel 15. A similar ratchet wheel shaft gears on to a counter shaft which is geared to the sprocket wheel shaft provided at the extremei end of the outlet tank, and the ratchet l 'ver on this ratchet wheel shaft is driven from the ratchct lever on the first said shaft by means of an arrangement of links and connecting rods. One of these 35 pxtends from the first ratchet lever to a pivotedlever 34: mounted above the furnace which by a horizontal connecting rod 36 is connected to another pivoted lever 34 at the other end of the furnace and this by an inclined connecting rod 35* is connected to the other ratchet lever.

In order to obtain a variation in the travelling speed of the conveyor chains, it is preferred to employ on each of the ratchet wheel shafts an arrangement ofthree ratchet wheels 2626 --26 close together made with their teethof different pitches so that the pawls can be moved to gear with either of' the ratchet wheels according to} the speed of travel of the conveyor chain re uired.

@Tn order to prevent any possibility of the set of sprocket-wheels at the inlet end over running the sprocket wheels at the outlet end which might be caused through the pawl at the outlet end from some cause failing to engage the ratchet wheel and turn the ratchet wheel shaft, it is preferred for there to be end any suitable free wheel such as that shown in Figure 4 and indicated by the.

' introduced in the driving gear at'theoutlet the outside links, each tooth being preferably formed with a flat plate portion forming a sector of a circle of the same diameten as the intermediate disc to which these plates are bolted or otherwisesecured so that they can readily be removed and replaced when worn or broken. v

6 In combination with the end sprocket wheels, suitable guide rollers 44: are provided to maintain the advancing .chain in the best sition for the sprocket teeth to engage with it and also to cause the chainsto properly disengage the sprocket teeth as. they leave them. Between the inlet mouth" of the heating chamber and the sprocket wheel's adjacent thereto, it is preferred to provide a narrow clearing plate 45 which just clears its,

the sprocket teeth on the sprocket wheels and causes the proper disengagement of the chains from the sprocket teeth and prevents the chains from being carried down out of the horizontal with the sprocket teeth.

Instead of the pawl and ratchet wheel intermittent driving gear above described for driving the sets of the sprocket wheels simultaneously, any other suitable arrangement of driving gear may be employed for this purpose, such driving gear being either intermittent or continuous.

Moreover, my invention comprises improvements in the construction of the hoods which are fitted on the mouth pieces of the heating chamber and dip into the water in the tanks to form the seals. Each of these hoods I preferably form of an end frame 50 which has an opening 51 corresponding with the opening in the flanged mouth piece of the heating chamber to which this frame and flanged side plates are bolted or otherwise fixed and covering the top and inclined front of the hood there ars steel or other plates 52 which are bolted or otherwise fixed to the two cast iron side plates. Thus there is formed a comparatively inexpensive and easily made hood having enclosed sides and top and front with an open bottom and open end to the heating chamber.

The said cast iron side plates of the hood are preferably provided with man holes furnished with suitable covers, or have easily detachable windows immediately over the said sprocket wheels so that they can be inspected, and so as to facilitate the release of any goods on the conveyor chain which may have fouled the hood.

\Vhat I claim then is I l. A continuous annealing furnace comprising a heating chamber, liquid seals for both ends of said heating chamber, an endless conveyor for the goods passing through said heating chamber and in slack loops through said water seals, and means for positively driving said conveyor at the same speed at both ends of the furnace, whereby the conveyor loops in the water seals are maintained.

2. A continuous annealing furnace com-- prising a heating chamber, liquid seals for both ends of said heating chamber, an endless conveyor for the goods passing through said heating chamber and in slack loops; through said water seals and inter-connected driving gear for positively driving said conveyor at the same speed at both ends of the furnace whereby the conveyor loops in the water seals are maintained.

3. A continuous annealing furnace comprising a heating chamber, a liquid seal for the ends of said heating chamber, an endless conveyor for the goods passing through said water seal and heating chamber, and means for positively driving said conveyor at the same speed at both ends of the furnace whereby the conveyor can han in loops in the water seal at each end of t 1e heating chamber and thus carry the goods through the liquid on its way to and from the heating chamber, and a free wheel device to permit the driving gear to be run independently of the drive.

4. A continuous annealing furnace comprising a heating chamber, a liquid seal for the ends of said heating chamber, an endless conveyor for the goods passing through said water seal and heating chamber, inter-connected driving gear for positively driving said conveyor at the same speed at both ends of the furnace whereby the conveyor can hang in loops in the water seal at each end of the heating chamber and thus carry the goods through the liquid on its way to and from the heating chamber, a driving shaft for actuating said driving gear, and a free wheel device to permit the driving gear to be run independently of the drive.

5. A continuous annealing furnace comprising a heating chamber, liquid seals for both ends of said heating chamber, an endless conveyor for the goods passing through said heating chamber and in slack loops through said water seals, sprocket wheels for positively driving said conveyor at each end, and means for driving said sprocket wheels at the same speed at both ends of the fur nace, whereby the conveyor loops in thewater seals are maintained.

6. A continuous annealing furnace comprising a heating chamber, seals-for both ends of said heating chamber, an endless conveyor for the goods passing through said heating chamber and in slack loops through said water seals, discs mounted for rotation at spaced intervals along the length of the furn-ace,; and adapted to support said conveyor, and means for positively driving all of he discs at the same speed, whereby the convy0r loops in the water seals are maintained.

In witness whereof I afiix my signature. MAR-TIN VAN MARLE.