US1779435A - Metal-heating furnace - Google Patents

Description

Oct. 28, 1930. R. KAIER METAL HEATING FURNACE Filed Aug. 3, 1927 5 Sheets-Sheet l R. KAIER 1,779,435

'5 Sheets-Sheet 2 METAL HEATING FURNACE Filed Aug. 3', 1927 Oct. 28, 1930.

DICE! Get. 28, 1930.

R. KAIER fi,7?9,435

METAL HEATING FURNACE Filed Aug. 5, 1927 5 Sheets-Sheet 5 Oct. 28 1930. R. KAIER METAL HEATING FURNACE Filed Aug. 3, 1927 SSheets-Sheet 4 Oct. '28, 1.930.

R. KAIER IETAL HEATING FURNACE Filed Aug. 3, 1927 5 Sheets-Sheet 5 I u I t: H .HAu. EE w 9 5 3 EB Ban gwuentoc Patented Oct. 28, 1930 UNITED RICHARD KAIER, 0F CRANFORD, NEW JERSEY, ilfitfillG-Iii NEW JERSEY, ll. UQIZM QHA'JIIQIQ" fill HEW {FIE-TEE TUBING COMPANY OF ELIZABETH,

METAL-HEATING FURNAGIEJ Application tiled August 3, 1927. Serial Mo. 2165,?

This invention relates to metal heating furnaces and has for an object to provide a furnace equipped with worlecarrying means for the continuous handling in quantities of small parts to be hardened by being heated uniformly to a definite temperature and then quenched.

A further object of the invention is to provide for the handling of the work pieces without subjecting them to the danger of deformation heretofore caused by moving the parts relative to their supporting means.

To this end, the furnace preferably comprises an elongated heating chamber with heavily insulated walls within which is supported a double track-way having work-carrying and return runs between a loading station at one end of the furnace and a clumping station at the other end of the furnace. Supported by the track-way are two trains of flat, open-topped work-carriers or trays, one train being on the work-carrying run and the other being on the return run. The length of each train is one work-carrier length less than the lengthof the track-way, and crossoverways are provided at the end of each run for transfer of the leading work-carrier to the other run. Suitable propelling means are provided for laterally transferring the leading work-carriers along the cross-overs and for propelling each train of work-carriers along its respective run. Means are also provided for discharging the work from each work-carrier When it reaches the dumping station. The provision for return of the empty work-carriers within the furnace to the loading station conserves the heat of work-carriers and avoids the necessity of re heating them. Thus the temperature of the work-carriers remains substantially constant at the furnace temperature and'the only heat loss is that which escapes with the quenching of the work plus the lnevitable losses which latter-are reduced to a minimum by suitable insulation. The maintenance of the work boxes at a constant temperature by keeping them substantially wholly within the heating chamber enables the furnace temperature to be easily controlled within close limits, which would be difiicult to do were the work boxes entirely removed from th lowed to cool more peratures.

In the accompanying drawing. is side elevation, partly in section, or a fur"" embodying the invention. Fig. Q is verse side elevation of the furnace. is a horizontal sectional view three furnace showing the work-carriers Fig. 4 shows the track-way for the r riers. Fig. 5 is a section on the in. a. Fig. 3. Fig. 6 is a section on the line Fig. 3.- Figs. 7, 8 and 9 are detail views of the worlccarrier tilting mac 10 is a section of the spe gear or diiferential shafts which pr el the 11 is a perspective view or o carriers. Fig. 12 is a shipper actuatii'w throwing-in and Q speed drive, and Fig. la ing the relative tini' I for one complete rotation or. shafts.

In the preferred embed! tent of tion illustra l f bar in the form of ctangular box having side walls 9;, 3, end-walls 4t 5, a bottom wall 6 and. a top wall 7, constructed of suitable refractoly material such as fire brick, and supported by legs 7. A series of gas-burners 8, directed into the chamber 1 through the side walls thereof, supplies the as heat to maintain the chamber and its contents at the desired steady running tem erature.

Supported on stilts 9 within the chamber 1 is .a work-carrier support 10, prefer Y of some suitable heat-resisting alloy, such. as the well known nickel-chromium alloys: This support is in the form of a rectangular plate having the longitudinal pairs of ridges 11, 12 constituting longitudinal runs or traclc enama ways in SldG-bj U flfi relation between the as; loading station i cat/ed at A, Figs. 1 and 3, and the dumpir at the opposite ends of the fur Vs. sta ns and B the wortecarrier s pport mica crossover 1% ice Carried by the support is a complement of work-carriers in the form of trays, each having an opened front end 16, side walls 17, a rear wall 18 and downwardly extending guide-lugs 19 which engage the inner sides of the several track-ways. The trays are arran ed in two trains, a work-carrier train C on t e run 12 and areturn or empty train D on the run 11. The length of trains C and D is one tray-length less than the distancebetween stations A and B whereby space is provided at the rear end of each train for the transfer or cross-over of the leading tray of the other train. Train C is propelled by the lever 20 which is-fulcrumed at 210m the bracket 21' and has a cam-follower 22 entering the cam groove 23 in the cam-disk 24 earned by the cam-shaft 25, which latter is journaled in the bearing brackets 25 secured to the under side of the furnace. Train D is propelled by the lever 26 which is fulcrumed at 27 on the bracket 27' and has a cam-follower 28 entering the cam-groove 29 in the cam-disk 30 carried by the cam-shaft 31 journaled in the bearing brackets 31'. When the leading tray of train 0 has been discharged of its contents, itis propelled over the cross-over at station B by means of the lever 32 which is fulcrumed at 33, Fig. 6, and has its lower end connected by a link 34 to the cam-follower 35 at the lower end of the link 36 pivoted at 37 to the bracket 38. The cam-follower 35 enters the cam-groove 39 in the cam 40 fixed to the shaft 31. The leading tray of train D is propelled over the cross-over at station A by means of the lever 41 fulcrumed at 42 on the bracket 43 and having a cam-follower 44 entering the cam-groove 45 in the barrelcam 46 fixed to the shaft 25.

The cam- shafts 25 and 31 are gear-connected to the shaft 47 which is journaled in the bearing brackets 47 and drives the two camshafts in timed relation at the same speed. The drive-shaft 47 has fixed to it a gear 48 with which meshes a worm 49 on the shaft 50 to which is keyed the fixed pulley 51 driven by the belt 52 from the pulley 53 on the counter-shaft 54 to which is fixed the pulley 55 iflrivezn by the belt 56 from the motor-pul- It will be observed from Figs. 1, 3 and 5 that one corner of the furnace is cut away at loading station A to expose the beginning end of the trackway 12. When a work-carrying tray 15 is pushed along the cross-over at A by the lever 41, it is momentarily exposed for reception of work-pieces which are placed therein by an attendant.

The discharge of the work-pieces from the carrier-trays is efl'ected by tilting each tray when it reaches the dumping station. To this end there is mounted in a vertical slideway 58 in the bottom wall of the furnace, Fig. 7, a bar 59 the upper end of which enters the slot 60 in the track-way 10. The bar 59 is bifurcated at its lower end and carries a cross-pin 61 which passes through a slot 62 in one end of the lever 63 fulcrumed at 64 on the bracket 65. The lever 63 carries a camfollower 66 which is actuated by the cam 67 on the cross-shaft 31. The bar 59 is so located that when it is lifted by action of the cam 67 on the lever 63 it enga es and lifts the rear end of the leading tray 0 train C, thereby tilting said tray, as shown in Fig. 1, and causing the work to slide out of such tray into the chute 68 which leads downwardly through the aperture 69 in the track-way 10 to the quenching tank 70.

To dislodge any work-pieces which may tend to stick to the tray, means are provided for jarring such tray while in tilted position. To accomplish this there is mounted at the under side of the furnace a bracket 71 in which is swiveled on pins 72 the fulcrum block 7 3 having in it a slot 74 throu h which passes the lever 75 fulcrumed on t e crosspin 76. The outer end of the lever 75 is connected by a link 77 to the lever 78 fulcrumed at 79 on the bracket 80. The lever 78 bears upon the cylinder 81 in the path of the tooth 82, which cylinder and tooth are carried by the shaft 83 driven by a belt 84 from the pulley 53 on the counter-shaft 54. A spring 85 pulling upwardly on the outer arm of the lever 75 restores such lever to horizontal position after each actuation thereof by the link 77. A spring 86 tends to swing the lever 75 to inoperative or dotted line position, Fig. 8, where it oscillates idly under the action of the quick down pulls or jerks imparted to the link 77 by the tooth 82.

After a tray has been tilted by lift of the bar 59, the lever 75 is swung from dotted to full line position, Fig. 8, wherein the inner end of the lever 75 extends under the bar 59 and imparts a series of upward impulses of comparatively small amplitude to the bar 59, thereby jarring the tilted tray and effecting dislodgement of any work-pieces which may have stuck therein. The lever 75 is swung to operative position by the ac tion of the cam 87 on the lateral pin 88 carried by the swivel-block 73. The swivelblock 73 has a lateral swell 89 Fig. 8, which is adapted to engage the bracket 71 and operate as a stop to limit the movement of the swivel block 73 and lever 75 under the influence of the spring 86.

The relative timing of the several cams is shown by Fig. 13 illustrating one complete cycle of movement or one complete rotation of the cam-shaft. The cross-feed of a tray at station A is first effected by the cam 45 acting upon the lever 41. Upon return of the lever 41 to initial position, the cross feed of a recently dumped tray at station B from train C to train D is effected by the action of the cam 39 upon the lever 32. The tray fed to station A by lever 41 remains exposed at such station for a brief interval, say 2 or 3 seconds, for reception of a load of workpieces whereupon train C is advanced a traylength and the recently loaded tray is propelled into the furnace by the action of the cam 23 on the lever 20. As the lever 20 is returning to initial position the cam 29 acting upon the lever 26 is effecting the feed of empty train D a tray-lengthQ The feed oftrain C carries its leading tray to the dumping station B and upon its arrival at such station the cam 67 effects the lift of the bar 59 to tilt the tray. As soon as the tray is tilted, the cam 87 swings the vertically oscillating lever under the lower end of the bar 59 to jar the tray. Upon the return of the lever 75 to inoperative position, the cam 67 effects the lowering of the bar 59 and the restoration of the tilted tray to its horizontal position. The several actions are grouped to take place during a little more than half of a revolution of the cam-shafts, there being no action during the remainder of the revolution.

In the particular machine described the time of one cycle is about 17 seconds which multiplied by 8, the number of trays on run C, gives 136 seconds or 2.26 minutes as the minimum time of passage of a workpiece through the furnace. To provide for an increase in the time of a cycle of any desired extent, to suit the character of the particular work being heated, there is mounted on the shaft 50, adjacent the fixed pulley 51 a differential pulley 90 onto which the belt 52 is shifted by the belt-shipper slidebar 91 mounted in the bracket 92. The beltshipper bar 91 is actuated by the bellcranklever 93 which is rocked to-and-fro by the cam blocks 94 which are clamped to the rim of the disk 95 fixed to the shaft 47. By shifting the cam-blocks 94 peripherally of the disk 95, the slow drive may be started and stopped at any desired time in the cycle and the time of a cycle extended as desired. Preferably, the slow drive is started and stopped during the portion of the cycle when the cams are not in action,

The differential pulley 90 is of standard construction. It is loose on the shaft 50 and carries bearing-pins 96 for the connected pairs 97 of gears of slightly different sizes. The inner gears mesh with a gear 98 fixed to the shaft 50 while the outer gears mesh with a gear 99 on the hub of the ratchet 100 on which rests the pawl 101 having a fixed pivot 102. When the belt is on the difi'eren tial pulley 90 the pawl 101 prevents retrograde motion of the gear 99 and holds such gear stationary. When the belt is shifted to the fixed pulley 51 the gear 99 and ratchet 100 are free to rotate at the higher speed.

While there is shown and described in detail one specific embodiment of the invention, it is to be understood that the invention is not limited to the details of construction which may be variously modified by those skilled in the art within the spirit and scope of the invention.

Having thus set forth the nature of the invention, what I claim herein is:

1. In a furnace, an elongated heating chamber having a work-receiving station at one end and a work-discharging station at the other end, a series of se arate work-carriers arranged in two si e-by-side trains within said heating chamber, one an outgoing work-carrying train and the other a return ,trainof empty work-carriers, means for discharging the work from the workcarriers and from the furnace at the discharging end, and means for transferring the work-carriers from the out-going train to the return train. 1

2. In a furnace, a heating chamber having a work-discharging station, a series of separate work-carriers with means for moving them within said chamber to said work-discharging s'tation, tray-tilting means at the work-discharging station, and means for jarring said tray-tilting means.

3. In a furnace, a heating chamber, two side-by-side track-ways within said chamber, cross-over ways at the opposite ends of said track-ways, trains of separate work-carriers on said track-ways, a pair of train propeller levers and a pair of cross-over propeller levers pivoted below said chamber and having their free ends extending in the same direction into the latter, and means for actuating said levers.

4. In a furnace, a heating chamber in the form of an elongated rectangular box, parallel track-ways disposed lengthwise of and Within said box, cross-overs at the ends of said track-ways, a complement of work-carriers carried by said track-ways, means for propelling said carriers, one corner of said box being cut away to expose one end of one of said track-ways to form a work-receiving station, and work-discharging means at the other end of said heating chamber.

5. In a furnace, a heating chamber in the form of an elongated rectangular box, a pair of cam-shafts ournaled below and transversely of said box adjacent the opposite ends of the latter, a shaft connecting. said camshafts in timed relation, means for driving said shafts, a rectangular track-way within said chamber, a complement of separate work-carriers on said track-way, a plurality of work-carrier propellers, and cams on said cam-shafts for actuating said propellers.

6. In a furnace, a heatin chamber, a trackway in said chamber, wor -carriers on said track-way, means for periodically propelling said carriers to and past a discharge station, a work-carrier tilting bar extending upwardly through the bottom wall of the furnace at the discharge station within the track-way,

and means for reciprocating said bar between the periods of movement of the workcarrier propellers.

7. In a furnace, in combination, a movable hearth, means for causing said hearth to travel through the furnace, means for moving said hearth to cause the discharge of material therefrom, and means associated with said discharge means to cause the hearth to vibrate at the time of discharge.

8. in a furnace, a tiltable hearth, means for tilting said hearth, and bumping means associated with said tilting means for agitating said hearth.

9. In a'furnace having a conveyor therein, a plurality of tiltable hearths mounted on said conveyor, means for periodically and successively tilting said hearths, and means associated with said tilting means for agitating said hearth.

10. In a furnace, the combination with a pivotally mounted hearth, and means for tilting said hearth, of means for causing jarring of hearth during the tilting action.

in testimony whereofll have signed my name to this specification.

RICHARD KAIER.

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