US1728371A

US1728371A - Heat-treating furnace

Info

Publication number: US1728371A
Authority: US
Publication date: 1929-09-17
Anticipated expiration: 1946-09-17

Description

P 1929- J. SHELTON ET AL 1,728,371

HEAT TREATING FURNACE Filed Jan. 11, 1929 3 Sheets-Sheet 1 INVENTOR5 A TTORNE Y.

P 17, 1929- I. J. SHELTON ET AL 1,728,371

HEAT TREATING FURNACE Filed Jafi. 11, 1929 s SheetsSheet 2 l NV EN TORJ 1e JTJs a 70 BY K144919155 Kfima/ A TTORNE Y.

P 17, 1929- J.-SHELTON ET AL 1,728,371

HEAT TREATING FURNACE Filed Jan. 11, 1929 3 Sheets-Sheet 3 3 INVENTORJ 2 [e 4 fJ/ zz ran/ 7 BY @flflLEJ l Jim a/ A TTORNEY.

Patented Sept. 17, 1929 I UNITED STATES IRAJ. SHELTON, F DETROIT, AND

PATENT OFFIQE HEAT-TREATING FURNACE Application filed January 11, 1929. Serial No. 331,883.

This invention relates to heat treating furnaces and the object of the invention is to provide a furnace for heat treating small steel articles in which the articles are carried through the furnace on a continuous conveyor' from the loading to the unloading position.

Another object of the invention is to provide a heat treating furnace-pf the charac ter described having movable electrical heating units which may be readily removed for repair or replacement if desired.

A further object of the invention is to provide a rotatable drum having a series of compartments arranged successively about the periphery thereof and adapted to carry the articles to be heat treated, the drum being.

slowly rotated to move the compartments from the loading position to the unloading position and through the heating zone.

These objects and the several novel features of the invention are hereinafter more fully described and claimed and the preferred form of construction by which these objects are attained is shown in the accompanying drawings in which- Fig. 1 is a vertical section through a; heat treating furnace embodying our invention.

Fig. 2 is a perspective view of one of the removable heating elements.

Fig. 3 is an end elevation of the heating furnace partly broken away to show the construction.

Fig. 4 is an end elevation of an alternative form of furnace.

Fig. 5 is a section through one of the article carrying compartments.

As shown in Figs. 1. and 3 the furnace 7 comprises a stationary housing 1 which is preferably lined with refractory material 2 at the sides, top and bottom. This housing 1 carries a pair of bearings 3 at the opposite ends in which a shaft 4 is rotatably mounted. Secured to the shaft 4 within the furnace 5 is a drum comprising a hub 5 secured to the shaft 4 by the pins 6 and this hub is provided with radiating fins or ribs 7 shown in Figs. 1 and 3. Secured to'these ribs is an annular member 8 having a .series of refractory facings 9 and a series of rectangular compartments 10 secured thereto by the rivets 11. These compartments. arefopen ended and are each adapted to receive a container 12 in which the articles to be heat treatedare positioned together with the carbon for carbonizing when the furnace is used as a carbomzmg furnace.

Openings 13 are provided in opposite ends of the furnace in alignment with which the container is positioned in the compartment the rotation of-the drum carries the con-"' tainer and compartment through the heat ing zone between the heating elements 14 provided in each end of the furnace as shown in Figs. 1 and 3, and within theheating elements 15 positioned adjacent the compartments in the exterior of the furnace. The heating elements 14 are each provided with a pair of terminals 16 to which a heating element 17 is connected and the ter minals 16 provide a means for connecting the heating elements in an electric circuit. The heating elements 15 are longer than the heating elements 14 and are each provided with a pair of terminals 18 as shown in Figs. 1 and 2 to which the resistance wire 19 is connected, as shown in Fig. 1.

This resistance wire 19 is similar to the resistance wire 17 of the heating element 14 and the terminals 18 provide a means for connecting the heating elements 15 in an electric circuit. The heating elements 15 are each provided with a longitudinal slot or opening 20 through which the resistance wire 19 extends and the heating elements 14- and 15 are each provided with a handle 21 by means of which the elements may be removed from or replaced in the respective openings in the housing 1. The exterior of each compartment 10 is apertured at 22 so that the heat will more readily penetrate to the articles being heat treated and annular grooves 23 are provided in the refractory lining 2 which are packed with soft flexible insulating material 24 such as mineral wool asbestos or like material. The flanges of the member 8 extend into this packing 23 and reduce the passage of heat toward the interior of the drum. The drum is also packed with refractory or insulating material 32 to reduce the heat passing into the interior of the drum and washers 25 are provided on the shaft 4 at each end of the drum to prevent overheating of the shaft 4.

The housing is provided with table brackets 26 adjacent the openings 13 throu h which the containers 12 are inserted into t 1e rotatable drum and these containers are carried in the compartments of the drum through the heating zone adjacent the heat--

ing elements

14 and 15 and after the heat treatment the containers are carried back to the openings 13 by the continuous slow rotation of the drum at which time a new container may be inserted into the compartment thus forcing the old container out as shown in Fig. 1.

An alternative form of the -device is shown in Figs. 4 and 5 in which the cornpartments are arranged to receive small articles individually. In this case the compartments are arranged as shown in Fig. 5 to provide slots 27 into which small articles such as bolts 28 may be inserted. For this purpose a loading table 29, .shown in Fig. 4, is provided at one side-of the drum adjacent which is an opening (not here shown) to the compartments. The bolts are inserted into the slots 27 in a horizontal position and are carried by the drum past the

heating.elements

14 and 15 to the opopsite side of the furnace and as the bolts pass to a position below the horizontal they fall out of the compartments onto a chute 30 which delivers them into a quenching tank 31.

From the foregoing description it becomes evident that the device is very simple and efiicient in operation, will not easily get out of order, will automatically heat treat the articles according to the speed of rotation of the drum and provides a device which accomplishes the objects described.

Having thus fully described ourinvention, its utility and mode of operation, what we claim and desire to secure by Letters Patent of the United States is 1. In a heat treating furnace, a housing having a refractory lining, a drum rotatably mounted in the housing, to rotate on a horizontal axis, a series of compartments mounted on the periphery of thedrum, each compartment being adapted to receive a container for articles to be heat treated, a series of electric heating elements removably mounted in the housing about a portion of the periphery of the drum, .a' seriesof heating elements removably mounted in opposite sides of the housing adjacent the compartments, the housing being provided with openings at the bottom through which the containers may be inserted in or removed from the compartments.

2. In a heat treating furnace, a housing having a refractory lining, a drum rotatably mounted in the housing, the drum being ar ranged to receive articles to be heat treated on the periphery thereof, a series of removable heating elements mounted in the housing on opposite sides of the drum adjacent the periphery of the drum, a series of removable heating elements in the housing about the periphery of the drum, the housing being provided with loading and unloading plat: forms between the ends of the-heating zone.

3. In a heat treating furnace, a housing having a refractory lining, a. drum rotatably mounted in the housing and havinga series of compartments on the periphery thereof, a series of heating elements mounted-on opposite sides of the drum in the housing and terminating adjacent the compartments, a series of heating elements in the housing spaced about the periphery of the drum, the housing being provided with an opening at the bottom of the drum through which articles may be inserted into or removed from the compartments.

,4. In aheat treating furnace, a housing having a refractory lining, a drumrotatabl mounted in the housing to rotate on a horizontal axis, a series of compartments mounted on the periphery of the drum, each compartment being adapted to receive a container for articles to be heat treated, the housing being provided with a series of openings therethrough about the periphery of the drum, and a. series of electric heating elements fitting in the said openings and extending adjacent the compartments, the heating elements being removable to allow access to the compartments or replacement of the heating elements.

5. In a heat treating furnace, a housing having a refractory lining, a drum rotatably mounted in the housing, a series of compartments mounted on the periphery of the drum, the housing being provided with a series of openings therethrough about the periphery of the drum, and a series of electric heating elements fitting in the said openings and extending adjacent the compartments, the heating elements being adapted for connection in an electric circuit and being removable to allow access to the compartments.

In testimony whereof we sign this specification.

IRA J. SHELTON. CHARLES V. JACOBI.