US1786508A

US1786508A - Apparatus for and art of treatment of metal work

Info

Publication number: US1786508A
Application number: US372457A
Authority: US
Inventors: Rosenberg Heyman
Original assignee: Individual
Current assignee: Individual
Priority date: 1929-06-20
Filing date: 1929-06-20
Publication date: 1930-12-30
Anticipated expiration: 1947-12-30
Also published as: FR704987A

Description

Dec. 30, i930. H. RosENBERG M7865@ APPARATUS FOR AND ART OF TREATMENT OF METAL WORK I S11/vanto@ 11.125 dttozuzq,

Filed June 20, 3 Sheets-Sheet l Dec. 3U, i930. H. ROSENBERG 3,786,508

I APPARATUS FOR AND ART OF TREATMENT OF METAL WORK Filed June 2o, 1929 s sheets-sheet 2 FIB 5 Dec. 30, 11930. 11,786,508

APPARATUS FOR AND ART OF TREATMENT OF METAL WORK H. ROSENBERG Filed June 20, 1929 3 Sheets-Sheet 5 i? YM/AN RUBEN 55H13/ raient @a sa, ieee i rus TENT HEYMAN BOSENBERG, QF NEW YORK, Ni 'Y.

Application filed .'lune 20,

This invention relates to improvements in the art of and apparatus for heat treating, and particularly case-hardening workl` and more especially work comprising a series of small parts, such as screws, nails, bolts, nuts, buckles, small tools, and the like.

A number of important objects are attained by the present invention which will best be understood by comparison with the most popular method and apparatus now in use for case-hardening purposes.

llt is, of course, well known that cyanide may be eEect-ively used for case-hardening purposes, and other salts are also commonly f' employed, but, for facility, convenience, and

brevity of discussion, cyanide will be particularly referred to herein with the reservation, however, that any other available salt may bel utilized accompanied by the varying and limiting conditions incident tothe known qualitications of substitute salts.y

lt is common practice to provide a vat heated by an appropriate furnace, such as a gas` furnace, and supplied with cyanide, or other required salts, and raised to the temperature ofliquefaction. The article or articles to be case-hardened are then lowered into the liquid cyanide and allowed to remain until the required temperature is attained. The article or articles are then lifted from the cyanide bath and quenched in water or other appropriate quenching fluid. The common mode of carrying out this practice has been to placethe articles to be hardened in a metallic basket or reticulated container having a long handle. The handle enables the operator to stand at some distancefrom the vat which is located over the furnace, but in doing so the operator is re- 3 quired to sustainthe unbalanced load at a tremendously disadvantageous leverage incident to the length of the handle. This load is manually lowered into the molten cyan1de, and when the required temperature has been reached, as indicated by the commonly used A electrical pyrometer, the operator grasps the handle and at the expenditure oi very substantial energy lifts the basketY of work from the vat, removes it from above the furnace,

3 and empties it into a vat of quenching ffluid.

1929. semi no. 372,457.

lt is common practice to hood the furnace and cyanide vat and vent the hood and also to provide effective general ventilation for the room or space in which the furnace is located, but the quenching vat must necessarily be spaced from the furnace and the load of heated Work must be withdrawn from the hood, carried to the water, and discharged. F unies of the cyanide inevitably escape into the air and drippings of cyanide fall onto the'oor of the room, and the operator is injured by the condition of the air before the ventilating system can eectively dispose of the fumes. Furthermore, the cyanide on the tloor becomes slippery and renders labor the more ditcult. When dry on'the floor, the cyanide is removed therefrom with diiculty and creates a cyanide dust which is injurious.

Under these conditions, the labor problem becomes an important factor both because it is not always easy to get men possessing sufficient physical strength and endurance to undertake the labor, and it is imperative that a change be made frequently it cyanide poisoning of the operator is to be prevented, so that rotation of laborers tends toward lack of eciency, since each new man must be trained in his task. Furthermore, the operator some times receives a burn from a drop of cyanide which is liable to produce a quite serious condition, and at other times when the door to the hood is open and the Y operator withdraws the basket, he is momentarily choked by the fumes, and stopping to catch his breath holds the basket in the air and thus allows a certain amount of cooling of the Work, which proportionally decreases the ecacy of hardening incident to quenching. rlhese are a few of the dimculties and problems, of which there are many others, in the art of cyanide case-hardening, all of which are overcome by the pres? ent invention.

Among the various objects in view, A,the present invention provides the following:

(1) Avoidance of undue exposure of the work to air before quenching, and thus af- :fonds a uniform and even penetration.

(2) Direct hooded ventilation for the 'furnace, the molten cyanide, and the quenching tank, whereby escape of cyanide fumes to the air being breathed by the operator is avoided.

(3) Prevention of waste of cyanide and the return of all cyanide drippings to the furnace pot or vat.

(4) Saving of time and expense inenabling one operator to care for a series of furnaces, whereas the present known methods require at least one operator for each furnace.

(5) Very substantial reduction in 'labor' required, sothat the operator docs not become exhausted and his eciency reduced as the day progresses, which' is known to occur in the old method of cyanide case-hardening.

(6) Uniformfefficiency in the operationof allfurnaces and in -the product from each.

(7) Avoidance of cyanide or water from dripping or splashing onto the floor, avoidance of water splashing into or otherwise reaching the cyanide vat, and avoidance of burns by cyanide or hot water.

(8) Substantial saving of ioor space.

(9) Substantial saving of equipment and particularly of the work containers or baskets which, under the old method of manual handling, became dented, bent, and so injured by impact as to be destroyed beyond capacity for further use in a comparative short time; whereas by the present invention the basket is never thus injured, and under the present invention a basket will last many times longer than a basket under the old method. The saving of wear and tear on the basket is so great that under the new methoda basket will frequently ontlast the basket of the old method fifty times or more.

(10) Substantial saving in every directionand particularly and especially in time, as the operation is uniform and never interrupted by mishaps such as occur when manual handling is required.

)Vith these and other objects in view as will in part hereinafter become apparent and in' part be stated, the invention comprises both the method of handling and the constructions, combinations, and arrangements of parts for handling as subsequently specified and thereafter particularly pointed out in the appended claims.

In the accompanying drawings,-

Figure 1 is aview in side elevation of apparatus embodying the features of the present invention, parts being broken away and parts seen in section.

Figure 2 is a top plan view of the parts seen` in Figure 1 with the hoods omitted. A

Figure 3 is a fragmentary, vertical section through the basket-carrying plate and contiguous parts, parts being seen in elevation, and the section being taken approximately on the plane indicated by line 33 of Figure 2.-

Figure 4 is a fragmentary end view of the same.

Figure 5 is a detailed, sectional elevation of a modified form of gearing.

Figure 6 is a vertical section taken on the plane indicated by line 6-6 of Figure 1, and looking toward the furnace.

Figure 7 is a horizontal section taken "(approximately on the plane indicated by course, any other source of heat may be pro`L The furnace 1 con-- vided for the furnace 1. sists essentially of a housing mounted on legs or supports 2 and covered by a plate 3,

the plate resting on appropriate portions of the angle iron or other suitable framing of .j

housing l. Mounted on the plate 3 is a table 4 provided with a pendent flange 5 surrounding the housing 1. Clamping bolts 6 anchor the plate to lower portions of housing 1. The table 4 is provided with an upstanding ange 7, preferably of substantially rectangular form. Table 4 is preferably provided with an edgewise extending projection 9, apertured at 8, to receive the hereinafter mentioned thermocouple as a supporting bracket therefor when the thermocouple is not in use. The plate 3 is apertured centrally and table 4 is provided with an annular, pendent flange 10 snugly fitting in the central aperture of plate in and bordered by flange 10. A furnace pot `or vat 11 extends through the central aperture of table 4- and is supported on the table by a laterally extending annular flange l2. The pot or vat 11 regularly contains the cyanide or other salts. In cyaniding and like case-hardening, it is customary to determine with precision the attainment of the requisite temperature by employing an appropriate pyrometer whose thermocouple 13 is arranged with its thermo-sensitive resistance within the pot 11 and provided with a circuit 14 of common and well known construction.

For facilityy of relative reference, it may be considered that that side of the apparatus seen in Figure 1 is the front of the apparatus. Thestable 4 at its right side extends beyond furnace 1 and is provided with pendent portions 15, seen best in Figure 4, which aie perforated and provide bearings for a shaft 16. Shaft 16 extends beyond the rear face of the apparatus and is there yengaged by an ad- 4justable counterbalance arm and weight 17.

The forward end portion of shaft 16 projects beyond the table and carries a spur gear 18 meshing with a pinion 19 fixed to a jack shaft 20.y rl`he shaft 20 is journaled in an enlargement of Harige and in a pendent flange from a bracket 21 preferably formed integral with the table 4. An appropriate housing 22 encloses the

gearing

18 and 19, and an operating handle 23, or other appropriate power means, is fixed to the shaft to enable rotation or oscillation of shaft 16.

F ixed'to the shaft 16 and extending across one portion of the table 4 and covering the vat or furnace pot 11, during the heating operation, is a. crank arm 24. The crank arm 24 is preferably in the form of a rectangular plate, but may, of course, be a framework or merely spaced bars appropriately connected, as hereinafter indicated. rl`he plate making up the crank arm 24 is provided with pendent ears 25 surrounding the shaft 16 and anchored thereto by cross pins 26 penetrating said ears and shaft. rll'ous, when the shaft 2O is rotated, the plate 24 will be swung about and with the shaft 16.` The plate 24 is preferably provided with longi-y tudinal,

marginal flanges

27, 27, terminating at the ends of the plate. Near the free end of the plate 24 an aperture 28 is provided to permit the passage of a basket 29. The basket 29 is, of course, capable of a wide range of variation in form and construction, but preferably consists of a reticulated receptacle adapted to withstand the action to which it is subjected. rlhe body of the basket 29 is sustained by straps of appropriate dimensions and stability, some of whichiextend upwardly through the aperture 28 and are formed with overlying flaps, tabs, or end portions 30, each bolted, riveted, or other- Wise appropriately fixed at 31 to the plate or crank arm 24. The parts are so located with respect to each other that'when the plateor crank arm 24 is in its lowermost position above the table 4, the basket 29 will be extended within and'preferably centrally of the vat or pot 11, so that the metal work comprising the contents of the basket 29 will be subjected to the action of the molten contents of the vat.

A quenching tank 32 is arranged at one side of the furnace 1, and preferably spaced an appreciable distance below the level ofthe crank arm or plate 24 when the same is in position with the basket 29 in vat 11. The

spacing should be sucient to insure against A splashing of the quenching liquid from tank 32 over to vat 11. The quenching liquid will ordinarily be water, but may, of course, be oil or any other acceptable quenching fluid. Arranged Within the tank 2 is a reticulated tray 33, which is preferably formed on a continuous curve so as to be arcuate in longitudinal cross section, as indicated in Figure 1,*

sheet metal housing engaged by a series `of

straps

34, 34, each extending to and fixed to an actuating shaft 35. 'The straps 34 may be secured by pins 36, or in any other acceptable fashion, to the 'shaft 35 to insure movement of the tray 33 incident to rocking of the shaft 35; An adjustable counterbalance 37 is provided for shaft 35, and an operating crank 38, or other appropriate power means, is also fixed to the shaft 35. A shaft 35 is arranged adjacent that end of tray 33 rcniote from the furnace housing 1, and the free end of the tray33 is adapted to rest on an v appropriate support 39 within the tank 32 when the tray 33 is in its work-receiving position.

Appropriate straps

40, 40 are fixed to the sides of the tray 33 and upstand there,- from and carry a cross bar 41 positioned to be struck by and interrupt the movement ofN f the basket carrying crank arm 24 during the discharge movement of the basket when the parts reach the discharging .position seen 1n dotted linges in Figure 1. t

At the right of the tank 32 is arranged an appropriate framework 42 supporting a hopper 43. A cross bar 44 is preferably carried by the hopper 43 to interrupt movement of tray 33 as it reaches its complete, discharging position, shown in dotted lines in Figure f lther treatment.

Arranged above the furnace housing 1 is a hood 46 converging to an appropriate due or vent 47, the hood 46 being constructed to snugly lit the` outer surface of the flange 7 to prevent leakage of fumes. rlhe Harige' 7, as best seen in Figure 2, is continuous eX- cept Wh'ere interrupted to. accommodate .the plate 24, and the hood 46 is similarly continuous except for a doorway to accommodate the Jswing of the plate 24 and its connected parts.

Snugly tting the upper portion of and closing the tank 32 is a hood 48 yconverging at its upper portion to a flue or other appropriate exhaust 49. The hood 48 includes also i a closing sheet 50 between the tank 32 and the furnace housing 1, and the hood 48 is pro- -.vided with a doorway similar to that formed in hood 46 to accommodate theswing of the plate 24 and its connected parts, as indicated in dotted lines in Figure 1. A vestibule hood 51 surrounds the said doorways and encloses the space therebetween so as to provide a sealed housing for all the area above and between the furnace and the quenching var or tank. The left or exposed face ofv the hood 48 is also closed by an appropriate wall, but a portion of the wall is formed into a freely vertically swinging door 52 adapted to swing outward as indicated in dotted lines in Figure and preventing exhaustion of fumes other wise than through the tlues el? and 157,

It should be understood that work may be supplied to the basket 20, when the latter is within the vat 11, by an appropriately arranged self-sealing discharge or caisson-like lock for admitting work without permitting exhaust of fumes, and that the work may be preheated within such lock from exhaust heat of furnace 1, all of which is illustrated in detail in my companion, copending application, and, therefore, not shown specifically herein. Likewise, itlis entirely feasible to make the operations completely automatic by providing electric motors for actuating 4the

shafts

16 and 35 successively in properly timed sequence and subject to the automatic control of electrical switch-closing devices governed by the condition of the pyrometer circuit or the apparatus actuated thereby, all as specifically disclosed in my said companion, co-pending application.

It is preferable to employ means for delivering work to the basket 29 without affording an opportunity for exhaustion of fumes, but a supply may be delivered to the basket 29 at an extreme minimum of risk of impregnation of air by providing a door 53 in the hood 4G which may be partly opened and the commonly used elongated scoop passed into position for delivering a charge of work to the basket 29, whereupon the scoop is withdrawn and the door 53 closed. Door 53, of course, will be maintained closed at all other times and at all times during operation when the sealing lock is utilized as above indicated. Door 53 is preferably provided with a pyreX plate 54, or other appropriate heat-resisting, transparent sheet.

door 55 is also. preferably provided for the hood L18 and the transparent sheet 56 similar to sheet 54 is arranged in door 55. rl`he

sheets

54 and 56 enable the operator to observe conditions within the respect-ive hoods and the

doors

54 and 55 are employed chiefly or wholly for access to the interior of the hoods when the apparatus is not in operation and the furnace 1 is not heated. 'lhe doors 55,

are provided with any appropriate locks`5frfor normally retaining them closed, but, of course, either door may be opened for emergency access to the interior of the hoods.

In the carrying out of the improved art by waartoe the improved apparatus above described, a

as the cyanide has become molten, the basket may be lowered into the bath in vat 11, and a supply of work will then be delivered into .the basket. The cyanide will melt atl about 800o F., while the lmelting' point of other salts varies from 600O to 1000o l?. llJhen the. cyanidehas attained the required temperature, ranging from 14t00O F. to 1600o F., according to the work being treated, the work is in condition for removal. 'll`he work is left in `the bath until the pyrometer reading indicates the attaining of the requisite temperature, and then the operator rotates the shaft 10, by actuating the handlesor levers 23, and thus elevates the basket 29by swinging the crank arm 24 upward. lil/hen the basket has reached a point above the liquid level in vat 2, the operator 'holds the parts in this position until the adhering molten cyanide dripsback into the vat. rlhe operator then continues his rotation of shaft to cause the basket 29 to be swung to the inverted position indicated in dotted lines in Figure 1. Most, and usually all, of the Work will at once fall from the basket into the quenching vat. llf any par ticular piece of work should, for any reason, remain in the basket, as by being lodged partially in one of the openings of the basket wall,V dislodgment may be effected by oscillating shaft 20-and causing the basket to gently tap the cross rod a1. The operator then reverses the rotation of shaft 20 and swingsthe basket 29 back to a position above the vat 11. It is preferable to lower the basket into vat 11 before a fresh charge of work is delivered to the basket. The introduction of the charge of fresh work is either accomplished through the sealed lock, not illustrated herein, but shown in the above referred to companion, (3o-pending application, or may be delivered by the use of a long scoop through the doorway closed by door 53. The introduction of the fresh supply of work reduces the temperature of the liquid in vat 11, and the operator must, therefore, Wait until the pyrometer indicates the re-attainment of the required high degree of temperature by the contents of vat 11 before again liftingl the basket 29 out of the vat.

While thus waiting for the rise in temperature, the operator will rotate the crank 38 for rocking the shaft from the position seen in full lines in Figure 1 to the position of discharge seen at the righthand of Figure 2 in dottedlines. As the tray 33 is elevated incident to this rocking of shaft 35, the door or gate 52 will be swung outward by the contact of parts of tray 33 therewith and part of the lll() menace into the hopper'43. The discharge will continue as the tray 33 approaches its outermost position, and if any parts of the Work have become caught or otherwise fail to discharge, the tapping of the tray against the cross bar 44 by gentle oscillation of shaft 35 will effect complete discharge. Meanwhile, the gate 52 will have swung back and the operator will then reverse the movement of shaft 35 and return tray 33 to its position Within vat 32. Gate 52 Will swing inward out of the path of tray 33 to permit the tray to move to its inner-r mostposition. and then the gate will swing automaticallyv by gravity back to its pendent, closed position. The parts are then ready for a repetition of the cycle of operation as just stated. Meanwhile, it will be observed that no opportunity is ai'orded for the fumes to escape into the surrounding atmosphere during any part of the time when fumes are liable to escape. 1t will also be observed that ample opportunity is afforded for the drain back of cyanide. and that no loss or detrimental results occur from cyanide dripping from the basket of Work. Also. the falling of the Work in the quenching bath does not. produce the harmful results of getting moisture into the cyanide bath. The vquenching bath is purposely set at a point suiiiciently below the level of the open upper end of the cyanide vat to insure against splashing of Water into the latter, and any Water which may be splashed onto the plate 24 or parts carried thereby Will drain back into the vat 32 or' beevaporated in the course of the upward movement of basket 29 during the return movement. of plate 2 4.

The

gears

18 and 19 While shown as spur gears may comprise any appropriategearing for accomplishingr the result intended, and it is important to note that the gear ratioA is preferablyY such as\to adord a substantial leverage to enable easy actuation and control of the crank arm or plate 24. Tothisend, also. a Worm may be provided for the shaft 20 arranged to actuate a Worm gear for actuating shaft 16. whereby a very substantial leverage will be provided, and at the same time the arm or plate 24 may be held at any given position Without the presence of the operator', the Worm gear acting asia lock to retain the parts against movement when not operated by manual or other power. A form of Worm gear connection isillustrated in Figure 5 in which shaft 16 is shown as provided with a beveled gear 18 meshing with a beveled gear 19 tired to a counter shaft 53 journaled in housing 22. Worm gear 59 is fixed to shaft 58 and meshes with the Worm 60 carried by the shaft 20 corresponding to illustrated. y

1t is. of course, Well understood that encessive heat of quenching liquid is undesirable ployed in the drain pipe to control the outfioiv relative and proportional to the inflow through pipe 61. lVhen Water is employed as the quenching fluid, the pipe 61 will lead from the city Water supply and the pipe 62 will lead to the sewer, but if oil or other substantially valuable liquid be employed, the pipes 61 and 62 may be parts of a circulating system including appropriate cooling means, not illustrated.

It will. of course, be understood that the thermocouple 13 is capable of being used in any acceptable manner, but l have found it preferable to remove the same from the molten salt with each operation, and, with that in mind, the arm or plate 24 is formed with an aperture 13', and the hood 46 is also formed `with an appropriate aperture through which the thermocouple 13 is introduced and from which it is Withdrawn. The thermocouple 13 is., of cour7 always Withdrawn immediately preceding a discharging movement of arm 24, and. as a matter of convenience, the thermocouple may be inserted through the opening 8 so that the part 9 will function as a Work and until the fresh Vsupply of Work hasy been delivered to the basket after its return to the vat 11. And, thereupon, the thermocouple is reintroduced into said vat.

ln this connection also, it should be noted that the opening in the hood through which the thermocouple 13 is inserted is comparatively small and substantially closed by the insulating head through which the Wires of circuit 14 entend, and, when preferred, a modified form of mounting may be utilized for the thermocouple, as shown in lliigure 3, in which the Wall 46a is that of the hood and is provided vvith an appropriate, parti-globular socket 46h in which is mounted a bearing hall 13a carrying the thermocouple 13h correspending in structure and function with thermocouple 13.` in appropriate heat-insulating handle 13o is preferably provided for manual manipulation of the thermocouple 13h to enable the operator to swing the thermoresponsive resistance at the inner free end of the thermocouple to and from the required position in the furnace vat. @bviously, any of various forms of joints7 including' a slot and slide connection, may be utilized to enable the required movement of the thermocouple Without leaving an opening through the hood,.but Whatever construction is ernployed must provide for sucient movement (ffl n temporarily to enable the thermocouple to be moved clear of the path of swing of the arm 24.

As best seen in Figure 6, the vestibule hood 51 is preferably of a width vjust sucient to snugly accommodate the necessary movements of the plate or arm 34 and i'tsconnected parts, which has the eect of largely discouraging access of moisture splashed from the quenching vat into or toward the hood 46, and as a further precaution against such access of such moisture, I preferably extend the walls of the vestibule hood 51-with in the hood 48 into a cowl or tunnel-,like structure having the side walls 51 and the cover 51 extended as far into the hood 48 as permissible while allowing the requisite swing of the door 52 incident to movements of the tray 33, the extent of the projection of the said cowl being best seen in dotted lines in Figure 1.

It should be understood that except forl continuously, operating furnaces, the contents of the vat 11 will solidify upon cooling down, as, when the plant is shut down overnight. It is best practice not to permit the work carrying basket 29 to remain in the vat 11 when the heat of the furnace has been turned off, and, therefore, when the plant is to be closed down for the night or otherwise shut down, the handles 26 are fastened in a position with the Y basket 29 elevated above the vat 11, and is not lowered again into the vat until the furnace has been started and the contents of the vat 11 has again become molten.

What is claimed is 1. In apparatus for case-hardening metal work, the combination, with a furnace and a vat located to be heated thereby, of a Work f carrierya quenching vat disposed adjacent the work carrier, and means for shifting the work carrier from within the first-mentioned vat to a position above the quenching vat for delivering the work to the quenching vat at substantially the temperature of the contents of the first-mentioned vat.

2. In apparatus of theclass described, the

combination, with a furnace and aV vat located to be heated thereby, of a shaft journaled at one side of the vat, an arm outstand- V ing from the shaft, a work carrier sustained by the arm in position for extending into the vat, and means for rocking the shaft for swinging the arm sufficiently to move the work carrier from the vat to an inverted position beyond the vat.

3. In apparatus of the class described, the combination, with a furnace and a vat located to be'heated thereby, of a shaft journaled'at4 one si-de of the vat, an arm outstanding from the shaft, a work carrier sustained by the arm in position for extending into the vat, `means for rocking the shaft for swinging the arm sufficiently to move the work carrier from the vat to an inverted position beyond the vat,

operating iffsaoe for rocking the shaft for swinging the arm sufficiently to move the work carrier from the vat to an inverted position4 beyond the vat, i l

and a quenching vat located to receive work A,discharged from the work carrier when swung to said inverted position, the quenching Vat being spaced relative to the first-mentioned vat to insure against splashing of liquid from the former to the latter. l

5. In apparatus of the class described, the combination, with a furnace/and a vat located to be heated thereby, of a shaft journaled at one side of the vat,an arm outstanding from the shaft, a work carrier sustained by the arm 'in positionvfor extending into the vat, means for rocking the shaft for swinging the arm -suiiiciently to move vthe work carrier from the lvatto an inverted position beyond the vat,

'and a quenching vat located to receive work discharged from the work carrier when swung to said inverted position, the quenching Vat being spaced below the plane of the upper terminus of the first-mentioned vat.

6. In apparatus of the class described, the combination, with a furnace land a vat located to be heated thereby, f a shaft journaled at one side of the vat, an arm outstanding from the shaft, a work carrier sustained by the arm -in position for extending into the vat, means lfor rocking the shaft for swinging the arm sufficiently to move the work carrier from the Avat to an inverted position beyond the vat for discharging work from the work carrier, means completely enclosing the work carrier throughout its movement, and .means for venting the enclosing means.

7. In apparatus of the class described, the combination, with a furnace and a vat located to be heated thereby, of a shaft journaled at one side of the vat, an arm outstanding from the shaft, a work carrier sustained by the arm in position for extending into the Vat, means for rocking the shaft for swinging the arm sufficiently to move the work carrier from the vat to an inverted position beyond the vat for discharging work from the work carrier, a quenching vat beneath the place of such discharge, means enclosing the full travel of said work carrier, and means for venting said closing means.

8. In apparatus of the class described, the combination, with a furnace and a vat ar# ranged to be heated thereby, of a work carrier, means for movingthe work carrier to and from said vat and to and from a discharging position beyond the vat, and a quenching Marrana vat disposed to receive the discharge from said `Work carrier and located to a'void splashing of liquid from the quenching vat to the first-mentioned vat. A

9. 1n apparatus oity the class described, the combination, with a furnace and a vat arranged to be heated thereby, of a Worl; carrier, means for moving the Work carrier to and from saidfvat and to-and from a discharging position beyond the vat.. and a quenching vat disposed to receive the discharge `from said work carrier and located suiicientlv below the Vplane of the upper terminus of the iirst-mentioned vat to prevent splashing of liquid from the quenching vatto the iirstmentioned vat.

10. 1n apparatus of the class described, the combination, `with arfurnace anda vat arranged to be heated thereby, of a Worlr carrier, means for moving the Work carrier to and fronrsaid vat and to and from a discharging positionfbeyond the vat, a quenching vat disposed to receive the discharge from said Work carrier, a hood enclosing the full travel of the Work carrier, and means for venting said hood.

11. 1n apparatus of the class described,`

the combination, with a furnace and a vat arranged to be heated thereby, of a Work carrier, means for moving the Work carrier to and from said vat and to and from a 'discharging position beyond the vat, a quench-V ing vat disposed to receive the discharge from saidrwork carrier, a hood enclosing the complete travel of the Work carrier and sealed relative to the vats for retaining fumes therefrom againstescape, and means venting said hood.

V ing vatdisposed to receive the discharge from said Worhecarrier, a hood sealed against the furnace and surrounding the vat thereof,

ahood superimposed on and sealed against the quenching vatand upstanding therefrom,

i j a sealed vestibule hood intercounicating said hoods and with said hoods providing the space for the path oitfthe worir carrier, and means for venting said hoods. L

13. 1in apparatus ot the class described, the combinatiomavith e furnace and a vat arranged to be heated thereby, ot a Work carrier, means for moving the Work carrier to and from said vat and to and tromv a discharging" position beyond Athe vat, a quenching vat' disposed-to receive the discharge from said vvorh carrier, hooding means itor sealing the vats and Work carrier at all times against dissemination of fumes, means for venting the hooding means, and

means for discharging work from the quenching vat. j y

14. In apparatus of the class described, the combination, with a furnace and a vat arranged to be heated thereby, of a. Work carrier, means for moving the Work carrier to and from said vat and to and from a discharging position beyond the vat, a quenching vat disposed to receive the discharge from said vvork carrier, hooding means for sealing the vats and work carrier at all times against dissemination of fumes, means Jfor venting the hooding means, means for discharging Work from the quenchingr vat, and an automatically closing door for enabling discharge of work from the quenching vat.

15. 1in apparatus of the class described. the combination, with heat treating means for metal work,'of a quenching vat adjacent thereto, hooding means for the heat treat-ing means, and quenching vat, means for delivering Work from the heat treating means to the vat within the hooding means, a tray Within the vat for receiving Work being quenched, and means for moving the tray to a position for discharging quenched Work beyond the vat.

16. in apparatus of the class described,'the combination, with heat treating means for metal Work. of a quenching vat adjacent thereto, hooding means for the heat treating means and quenching vat, means for delivering Work from the heat treating means to the vat Within the hooding means, a tray Within the vat for receiving 1.vork

being quenched, and means for moving the Work receiving tray from the vatto a discharging position beyond the hooding means. 17. 1n apparatus of the class described, the combination, With heat treating means for metal Work, of a quenching vat adjacent thereto, hooding means for the heat treating means and quenching vat, means for delivering Work trom the heat treating means to the vatvvithin the hooding means, a tray Within the vat y:for receiving work being quenched, means for moving the Work receiving tray trom the vat to a discharging position beyond the hooding means. and an automatically closing door for the hooding means for enabling such movement oit said tray.

18. In apparatus of the class described, the combination, with heat treating means for metal Work, of a quenching vat adjacent thereto, hooding means for the heat treating means and quenching vat, means for delivering Work trom the heat treating means to the vat Within the hooding means, a tray Within the vat for receiving 'Work being quenched, means for moving the Work receiving tray from the vat to a discharging position beyond the hooding means, and a pivoted, pendent door for the hooding means for enabling such movemei'it of said tray.

19. In apparatus of the class described, vthe combination, with heat treating means for metal work, of a quenching vat adjacent thereto, hooding means for the heat treat ing means and quenching vat, means for delivering Work from the heat treating means to the vat Within the hooding means, a tra7 Within the vat for receiving Work being quenched, a rock shaft izied to said tray at one side of said vat, and means fork oscillating said rock shaft for swinging the tray from the Work-receiving position to the discharging position and for returning the tray to the Work-receiving position.

20. ln apparatus of the dass described, the combination, With heat treating means for metal Work, of a quenching vat adjacent thereto, hooding means for the Yheat treating means, means for moving Work from the heat treating means to a position discharging into the quenching vat, and a cowl snugly enclosing the path of movement of the WorkY moving means and extending from the hooding means toward the place l of discharge into the quenching Vat.

21. In apparatus oit the class described, the combination, With heat treating means for metal Work, of a quenching vat adjacent thereto, hooding means for the heatV I treatingY means, means for moving Work from the heat treating means to a position discharging into the quenching vat, a cowl snugly enclosing the path of movement of the work moving means and extending from the hooding means toward the place of discharge into the quenching vat, and hooding means for the quenching vat enclosing a o portion of said cowl.

In testimony whereof l' afhn my signature.

HEYMAN RUSENBERG;