US2621033A

US2621033A - Conveying disk for heat-treating furnaces

Info

Publication number: US2621033A
Application number: US133567A
Authority: US
Inventors: William E Blythe
Original assignee: Driver Harris Co
Current assignee: Driver Harris Co
Priority date: 1949-12-17
Filing date: 1949-12-17
Publication date: 1952-12-09
Anticipated expiration: 1969-12-09

Description

Patented Dec. 9, 1952 CQNVEYING DISK FOR HEAT-TREATING FURNACES William E. Blythe, Birmingham, Mich, assignor to Driver-Harris Company, Harrison, N. J., a corporation of New Jersey Application December 17, 1949, Serial No. 133,567

3 Claims. 1

The present invention relates to high temperature heat-treating furnaces of the type in which the material to be treated is conveyed through the furnace on wheels or disks, and has special reference to the wheels or disks of such furnaces.

Ihe principal object of the invention is to provide a material-conveying disk of the character indicated which may be easily removed and replaced, and which is capable of withstanding the high heat of the furnace Without warping or otherwise being injuriously aifected.

Th invention is iliustrated, by way of example, in the accompanying drawings, in which:

Figure 1 is a transverse sectional View, partly in elevation, of a furnace having material-conveying disks embodying features of th invention in their preferred form;

Fig. 2 is a side view, partly in section, of one of the disks attached to a furnace shaft, the shaft being shown in section;

Fig. 3 is a sectional view, partl in elevation, taken on the line 3-3 of Fig. 2;

Figs. 4, 5 and 6 are sectional views, partly in elevation, taken respectively on the lines 4--i, E5, and 66 of Fig. 2; and

Fig. 7 is a plan view of a portion of the rim of the disk.

The furnace illustrated in Fig. 1 of the drawings maybe of the type of the one described and claimed in my Letters Patent Reissue No. 19,205, dated June 12, 1934; No. 1,992,466, dated February 25, 1935; and No. 1,992,467, dated February 26, 1935. This furnace is provided with a furnace chamber having side walls 2, a bottom wall 4, hollow conveyor rolls or shafts 6 extending transversely of the furnace chamber, bearings 8 within the chamber for supporting the shafts, material-conveying disks it carried by the shafts, the disks of the several shafts being arranged in staggered relation.

In accordance with the present invention, each disk ii is provided with a hub l2, radially extending spokes Hi, and a rim 1 6.

The hub 52 is made in two longitudinal sections which embrace the shaft with their opposed longitudinal edges spaced apart to allow for expansion and contraction.

Th two sections of the hub may be secured to the shaft by means of a bolt [8 which extends through alined apertures in the sections and shaft. As shown the bolt is held in place by means of a head It on one end thereof, and a taper pin 2i} removably secured in an aperture in its other end. The apertures through which the bolt extends are made slightly larger in diam- 2 eter than the bolt to allow for expansion and contraction and to permit the bolt to be easily removed upon removing the retaining pin 20.

The hub sections may also be removably secured separately to the shaft by means of a bolt 22 which extends through an aperture in each section, and its end which is reduced in diameter is screw-threaded into an aperture in the shaft. The apertures in the hub sections are slightly larger than the bolts to allow for expansion and contraction and easy removal of the bolt.

While for convenience both the bolt l8 and the bolts 22 are shown in Fig. 2, only one such securing means need be employed.

Three of the six spokes E4 of each disk project from each hub section, there being a central spoke and two spokes spaced from the central spoke. The spokes are provided with longitudinally extending reinforcing ribs 24 on the sides thereof, and the outer ends of the spokes have flat parallel sides and extend into an annular groove 26 on the inner side of the rim Hi. The

side walls of the groove 26 are spaced slightly,

away from the sides of the ends of the spokes to allow for expansion and contraction between these parts. The central spoke of each section is provided with a laterally enlarged outer end 28. The rim i8 is made in two sections with the split or opposed ends of the sections spaced slightly apart to allow for expansion and contraction, and are arranged at an angle of substantially forty-five degrees so as not to interfere with the travel of the material over the disks. The end portions of the walls of the groove 26 in the sections are provided with inwardly rojecting lugs or ears 30 which are provided with apertures in alinement with apertures in the enlarged ends 28 of the central spokes of the two hub sections. The ends of the rim sections are secured to the central spokes by means of bolts or screws 32 that extend through the apertures in one wall of the groove 25, and through the apertures in the ends of the central spokes, and are threaded into the apertures in the other wall of the groove 26, there being a slight clearance space provided between the outer portion of each screw and the walls of the apertures to allow for expansion and contraction and for easy removal of the screws.

With this construction, it will be apparent that the sections of the disks may be easily detached, and the disks separately removed and replaced without removing their shafts from the furnace 3 chamber, and the disks are of simple and strong construction.

Heat-treating furnaces of the type described are heated up to the high temperature of 1900 degrees F. at which they normally operate. When thus operated, the rims of the disks heat up considerably faster than the hubs. Conversely when the furnace cools down the rims cool considerably faster than the hubs. In the case of disks heretofore in general commercial use, this develops very severe thermal stresses which tend to warp the disks, and in some instances causes them to curve to such extent that the disks on adjacent shafts interfere. It will be apparent that with my specific construction, the rim and hub and the sections thereof are free to expand and contract independently of each other, and it has been found that the tendency of the disks to warp is effectively overcome.

As will be evident to those skilled in the art,

my invention permits various modifications without departing from the spirit thereof or the scope of the appended claims.

What I claim is:

l. A conveying disk for a shaft of a heat-treating furnace of the class described, comprising a hub made in two longitudinally extending sections, a centrally located spoke and spokes spaced circumferentially therefrom projecting radially from each hub section, means for detachably sewith its ends arranged centrally of said centrally located spokes, and means for detachably securing the ends of the rim sections to said centrally located spokes comprising members extending through apertures in one of the walls forming said groove and apertures in the ends of said spokes and detachably secured in apertures in the other wall of said groove, the sections of said rim, said rim sections and the ends of said spokes, the sections of the hub, and said securing means and connected parts, having clearance spaces between their adjacent surface portion to allow for expansion and contraction of the sections of said rim and the sections of said hub independently of each other.

2. A conveying disk for a shaft of a heat-treating furnace of the class described, comprising a hub made in two longitudinal sections, a centrally located spoke and spokes spaced circumferentially therefrom projecting from each hub section, means for detachably securing the hub sections about said shaft, a rim having an annular groove on its inner side for receiving the ends of the spokes of the two hub sections, said rim being made in two transverse sections with its ends arranged centrally of said centrally located spokes, and means for detachably securing the ends of the rim sections to the ends of said centrally located spokes, the sections of said rim, said rim sections and the ends of said spokes, the sections of the hub, and said securing means and connected parts, having clearance spaces between their adjacent surface portions to allow for expansion and contraction of the sections of said rim and the sections of said hub independently of each other.

3. A conveying disk for a shaft of a heat-treating furnace of the class described comprising a hub made in two longitudinally extending sections, a plurality of spokes projecting radially from each hub section, the spokes of the two hub sections being diametrically in alinement respectively, and the several spokes being spaced apart circumferentially, a rim having an annular groove in its inner side for receiving the ends of the spokes of the two hub sections, said rim being made in two transverse sections with its ends arranged centrally of the ends of two of the diametrically alined spokes of the two hub sections, and means for detachably securing the ends of the rim sections to the ends of said last mentioned diametrically alined spokes, the sections of said rim, said rim sections and the ends of said spokes, the sections of the hub, and said securing means and connected parts having clearance spaces between their adjacent surface portions to allow for expansion and contraction of the sections of said rim and the sections of said hub independently of each other.

WILLIAM E. BLYTHE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 288,522 Walker Nov. 13, 1883 393,041 Thorp Nov. 20, 1888 1,861,489 Brooke et al June 7, 1932 1,923,036 Knopf Aug. 15, 1933 1,923,772 Carpenter Aug. 22, 1933