US2579749A - Sprocket wheel construction - Google Patents

Description

Dec. 25, 1951 s. M. MERCIER 2,579,749

SPROCKET WHEEL CONSTRUCTION I Original Filed Sept. 1, 1945 2 SHEETS--SHEET 1 //v l/ENTo/e STANLEY M. MERCIEE,

Dec. 25, 1951 s. M. MERCIER SPROCKET WHEEL CONSTRUCTION 2 SHEETSSHEET 2 Original Filed Sept. 1, 1943 vE/w/To/Q STAN LEY M. MEQCI ER,

Patented Dec. 25, 1951 SPROCKET WHEEL CONSTRUCTION Stanley M. Mercier, Bexley, Ohio, assignor to The J effrey' Manufacturing Company, a corporation of Ohio Original application September 1, 1943, Serial No.

500,799. Divided and this application November 23, 1946, Serial No. 711,909.

June 12, 1944 In Canada 2 Claims. (01. 2638) My invention relates to sprocket wheels and more particularly to the construction of sprocket wheels adapted for use in elevators or conveyers.

An object of my invention is to provide an improved thermal compensating sprocket Wheel structure particularly adapted to carry hot chain elements of a conveyer apparatus constructed to convey hot material such as hot clay used in the cracking of petroleum.

Another object of my invention is to provide an improved sprocket wheel structure particularly adapted for use in an elevator or conveyer operating under conditions of heat in combination with a shaft which is cooled.

In carrying out the foregoing object it is a further object of my invention to provide an improved sprocket wheel adapted to be carried upon a shaft which is cooled wherein provision is made providing for expansion of the rim thereof with respect to the hub or central portion thereof.

Another object of my invention is to provide an improved thermal compensating sprocket wheel having removable chain engaging teeth.

Still another object of my invention is to provide an improved removable tooth adapted to be secured upon a conveyer sprocket wheel.

Other objects of the invention will appear hereinafter, the novel features and combinations being set forth in the appended claims.

In the accompanying drawings,

Fig.1 is a side elevational view of an elevator or conveyer incorporating the features of my invention;

Fig. 2 is a rear view of the head portion of the conveyer shown in Fig. 1, the view being taken on line 22 thereof;

Fig. 3 is a transverse, fragmentary sectional view showing one end of the head shaft and head sprocket and associated mechanism of the elevator or conveyer; and

Fig. 4 is a view of a tooth and associated parts of the head sprocket.

This application is a division of my co-pending application, Serial No. 500,799, filed September 1, 1943, entitled Elevator, now Patent No. 2,491,899, dated December 20, 1949.

The conveyer or elevator illustrated as a whole in Fig. 1 of the drawings comprises a vertical or upwardly extending tower or main frame 20 which is generally rectangular in cross section be, for example, mounted on a poured concrete base sufiiciently sunk in the ground to provide a firm foundation. At their tops the channel members 21 are rigidly connected together by side I-beams 23 and cross channels 24, all of said structural members El, 23 and 2&- being rigidly connected together. Along the sides, each of the two front and rear channel members 2| are connected by one or more diagonal braces 25 as well as horizontal angle members 26. Spaced moment members 2? connect the front and rear pairs of channels 2!.

Mounted upon the I-beams 23 at the top of the main frame 28 is a pair of spaced bearing boxes 29 which support horizontally extending head shaft 38 of a head assembly 3i that includes a pair of head sprocket wheels 32 which support and drive a pair of endless chain elements 33 of a bucket elevator or conveyer mechanism indicated diagrammatically in Fig. 1.. Extending between the two chain elements 33 and carried thereby is a plurality of material receiving buckets, not shown, that are rigidly attached adjacent their sides to the inner side bars of the chains 33 by appropriate brackets.

At the foot or bottom of the tower or main frame 20 there is a foot shaft 3? which is part of a foot shaft assembly 38 which includes a pair of spaced wheels 39 that receive and carry the two endless chain elements 33 of the conveyer apparatus. Foot shaft assembly 38 is mounted for floating guided vertical movement and is carried by a box-like frame 34 with which there is associated a counter-balancing mechanism 35 for counter-balancing weight of the box-like frame and shaft assembly.

Supported by the main frame 2!! and generally within the structural members thereof is a totally and at each of the four corners includes a vertical enclosing casing or housing 4B which includes as its three principal parts a head section 4|, a foot section 42 and a plurality of intermediate sections 43. All of these sections are preferably formed at least in part of insulating material so that the enclosing housing or casing is insulated. Also the head section 4i is provided with a discharge chute or spout 44 by which the material is discharged from the conveyer.

The foot part or section 42 of the housing or casing 40 includes a feed chute 45 by which hot clay or other material to be elevated is delivered preferably directly into the buckets at the bottom of the feed run of the conveyer mechanism. The foot section or part 42 also includes structure providing gas tight dust and heat seals for the foot shaft 31 which is mounted for substantially free or floating vertical movement through a limited range so as to compensate for changes in the lengths of the chain elements 33, particularly under the influence of temperature changes.

Attention is now directed to mechanism that traction wheel 37 with which a mechanically V operated brake device M; (Fig. l) co-operates. The drive sprocket 40 is driven from an appropriate motor and speed reducer 49 through an appropriate chain and sprocket or equivalent drive 50. The motor and speed reducing mechanism 49 is mounted on a platform formed on rearwardly extending portions of the I-beams 23.

Attention is now directed particularly to Fig. 3 of the drawings which illustrates one end of the head sprocket assembly3i, one of the bearing boxes 29 and certain associated apparatus, it being understood that the structure is duplicated on the other side of the elevator.

Mounted in spaced relation on the head shaft 30 are the head or drive sprockets 32, there being one foreach of the chains 33, as previously pointed'out, said sprockets 32 preferably being of similar construction. Each sprocket 32 includes a plate steel'center ring as preferably keyed and welded to the shaft 30 and forming a hub. The additional diameter of the wheel 32 is formed by a pair of concentric rings 99 and H30, the first being shrunk onto the center ring or hub 98 and the second being in turn shrunk onto the ring .99. In building up this wheel, the ring 99 is heated to a high temperature so that it can be forced or slipped onto the ring 38 and when it cools to atmospheric temperature it will be under tension.

Thereafter, the edges of the rings as and 09 are preferably welded together by welds I lI which may be either continuous or at spaced intervals along the periphery thereof. In a similar manner the ring I36 is shrunk on the ring 99 and attached thereto by welds I02 similar to the welds EU I. The ring N30 is also under tension at atmospheric temperature.

As a consequence of the above structure, the wheel 32 can expand or contract with variations in temperature without causing damage thereto and at the same time the structure is such that the parts'are held together both by friction and by welded connections. Because shaft 30 is cooled, as hereinafter described, the temperature of the wheel rim, which frequently reaches 1000 degreesF will be much higher than the shaft so within the housing 40, is embedded in a heavy drum I05 of insulating material which is preferably made up of sections which are split along a plane passing through the axis of the shaft 30,

transversely of itself. The drum I05 is also made in sections, there being at least one transverse section between the two sprockets 32 and two sections, one outside each of said sprockets, these transverse sections being connected together with tie rods I06. Similar tie rods I03 or tie bolts not illustrated, may interconnect the sections of drum I0,5 alon g their plane of severance parallel the axis of shaft 30.

7 As clearly illustrated in Fig. 3 of the drawings, the end of drum I05 is closely positioned with respect to the insulating material lining I01 of the head section ii of casing 40. The opposite ends of head shaft 30 extend through close fitting openings in the side walls of the head sectionl li and a stuffing box I03 is provided between each of said side walls and said shaft 30 which acts as a dirt and heat seal. A support for opposite ends of the shaft 30 is provided by' a pair of self aligning bearings, one of which is seen at I09. Said bearing I09 is preferably babbitt or bronze lined and is only semi-cylindrical in shape and supports the bottom portion of the shaft 30, since the load on the shaft 30 is always in a downward direction. The bearing I09 is enclosed and protected by the bearing box 29 which pro.-

vides a lubrication well. Oil drip rings IIO are provided on shaft 30.

It is important in elevators or conveyers of the type illustrated that the temperature of the wheel shafts be controlled because in spite of all of the insulation provided on the shaft assemblies temperature during operation of the conveyer.

' Mounted on the outer periphery of the ring l 63 is a plurality of removable sprocket teeth I63 and the bottom or root of each tooth I03 is provided with an arcuate groove which receives the I04 preferably being welded at one or two spots to the root of tooth I03 after the parts are assembled. To remove a tooth I03 the welded spot is burned off.

To protect the major portion of the two wheels 32 from the high temperature within the casing 49 and also to reduce the transfer of heat therefrom through the shaft 30 and to its supporting bearings, the principal portion of said sprocket 32, including the rings 98 and 99 and part of the ring I00 as well as the major portion of the shaft the shafts will become quite hot unless they are properly cooled. It is because of the cooling of the shaft 33 and the consequent large temperature differential between it and the rim of is formed as a hollow shaft. It will be under-e stood that the cooling mechanism is duplicated at each end of the shaft 30. Extending into the bore I2I a'pipe I22, the outer periphery of which is spaced from the inner periphery of the bore I2i. At its outer end the pipe I22 is provided with a fitting I23 which acts in the nature of a bearing. The fitting I23 is so constructed that a feed water elbow I24 connected thereto, will be effectively connected to the interior of the pipe 22 and a water discharge elbow I25 is effectively connected to a passageway formedbetween the exterior of the pipe I22 and the cylindrical surface provided by the bore I2I. The packing between the fitting I23 which is stationary and the rotating shaft 30 is provided by packing ring I25 and associated packing gland .2? which is attached by screws to the end of the shaft 30. The fitting I23 is mounted on a stationary bracket I28 which may be connected central portion of the shaft 30 and supports the inner ends of the pipes I22 associated with opposite ends of said shaft 30. It may be mentioned that axial movement of the pipes I 22 is prevented since the fittings I23 to which said pipes in opposite ends of the shaft 30 are screw-threaded, are held by the above mentioned stationary brackets I23. Filler rod BI is slightly smaller in diameter than the bore I2I and is pinned at its center to the shaft 3!] for rotation therewith.

To provide a thorough scouring turbulent flow of water in its return path from the holes I29 to the discharge elbow I25, I provide wire helix I32 which is preferably rigidly attached to the exterior surface of the pipe I22 and is closely adjacent to the cylindrical surface of the bore IZI, though slightly spaced from said surface, since the shaft 30 rotates while the wire helix I32 is stationary. It is evident that cooling water introduced by way of the feed elbow 124 will flow through the fitting 923 into the pipe 522 and out of the radial openings or holes 52!? and thence will return by a greatly elongated and helical path of reduced cross-sectional area to provide What is known as turbulent flow, during which it will scour the internal surface of the adjacent portion of the shaft 30 provided by the bore I2 2, ultimately flowing through the fitting I23 and the discharge elbow I25. This elongated helical path together with the scouring action will insure proper cooling of the shaft 30 and through it the bearin I09 so as to prevent burning out of said bearing and undue heating of the lubricating oil for it, which is within the bearing box 29.

In the operation of the conveyor or elevator hot material such as clay or fullers earth is fed to the feed chute 45 and by it directed into the buckets of the conveyer mechanism as they travel upwardly from the foot shaft assembly 38 along their working or elevating run. As the buckets travel over the head shaft 3i they discharge into the discharge chute 44 and the material flows therethrough and is discharged from the elevator at the top thereof. Provision has been made for free vertical counter-balanced movement of the foot shaft, which movement may be caused by differences in temperature within the casing or housing t0. Furthermore, the head sprocket wheels for the two strands of chain 33 have been especially consrtucted to take care of differences in temperature adjacent the outer rims thereof as compared with the hubs or portions thereof attached to the shaft 30.

From the foregoing description it will be obvious that I have provided an improved thermal compensating sprocket assembly and wheel therefor wherein provision is made for an extreme temperature differential between the outer rim of the wheel and the cooled hub portion thereof which may be cooled, for example, through an internally cooled supporting shaft. It will also be obvious that I have provided an improved conveyer wheel having removable sprocket teeth thereon and that the sprocket teeth are secured to the outer rim of the wheel through root members that form an arcuate slot between them for receiving the rim of the wheel and through which there are aligned openings for receiving a fastening or securingpin that may be pressed therethrough and permanently fixed therein by welding to one or both root members of the tooth. It will be seen that the separate teeth of each sprocket wheel 32 co-operate to form a segmented outer or toothed peripheral portion or rim that will not interfere with the thermal compensating features of the Wheel and should the teeth become worn they may be replaced readily by removing the pins I04.

Obviously those skilled in the art may make various changes in the details and arrangement of parts without departing from the spirit and scope of the invention as defined by the claims hereto appended and I wish therefore not to be restricted to the precise construction herein disclosed.

Having thus described and shown an embodiment of my invention, what I desire to secure by Letters Patent of the United States is:

l. A driving member for a conveyer adapted to convey hot material includinga shaft adapted to operate at a relatively low temperature, a thermal compensating sprocket wheel rigidly supported upon said shaft adapted to drive hot chain elements of the conveyer, said thermal compensating sprocket wheel including a hub member rigidly secured to said shaft and a plurality of concentric ring members carried by said hub, said concentric ring members being under tension at atmospheric temperature, sprocket teeth carried by the outer of said concentric rings each tooth having in its bottom a groove which receives said outer ring, the tooth thereby having root parts on opposite sides of said outer ring, means including pins extending tightly through aligned openings in said root parts and outer ring tightly attaching said teeth to said outer ring, and insulatmg material on said shaft embedding said wheels except for said outer concentric rings.

2. A QIlVlZlg member for a conveyer adapted to convey hot material including a shaft adapted to operate at a relatlvely low temperature, a thermal compensating sprocket wheel rigidly supported upon said shaft adapted to drive hot chain elements or the conveyer, said thermal compensating sprocket wheel including a hub member rigidly secured to said shaft and a plurality of concentric ring members carried by said hub, all of said concentric ring members being under tension at atmospheric temperature, sprocket teeth carried by the outer of said concentric rings each tooth having in its bottom a groove which receives said outer ring, the tooth thereby having root parts on opposite sides of said ring, and means ineludingpins extending tightly through aligned openings in said root parts and outer ring tightly attaching said teeth to said outer ring.

SiANLEY M. MERCIER.

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

UNITED STATES PATENTS Number Name Date 221,879 Torrey Nov. 18, 1879 784,544 Brinton Mar. 14, 1905 787,801 Stapf Apr. 18, 1905 846,529 Unger Mar. 12, 1907 2,188,025 Weiss Jan. 23, 1940 2,231,427 Larsh Feb. 11, 1941 FOREIGN PATENTS Number Country Date 17,706 Great Britain Aug. 11, 1896

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