US2302212A - Charging mechanism for heating apparatus - Google Patents

Description

Nov. 17, 1942.

A. .1. GRINDLE CHARGING MECHANISM FOR HEATING APPARATUS 2 Sheets-Sheet 1 Original Filed Aug. 12, 1936 Nov. '17, 1942. AIJ. GRINDLE CHARGING MECHANISM FOR HEATING-APPARATUS Original Filed Aug. 12, 1936 2 Sheets-Sheet 2 IN VENT OR. .fiargyf Grz'zzdle ATTORNEYS Patented Nov. 17, 1942 rsr orrics CHARGING MECHANISM FOR HEATING APPARATUS Aubrey J. Grindle, Chicago, Ill., assignor to Alwin F. Pitzner, Winnetka, Ill.

Original application August 12, 1936, Serial No.

Divided and this application December 22, 1939, Serial No. 310,487

1 Claim.

The present invention relates to improvements in charging or loading mechanism for heating apparatus, such as a rotary furnace adapted to melt various metals.

One of the objects of the invention is to provide a new and improved charging or loading mechanism for introducing the material to be treated into the heating apparatus.

Further objects and advantages will become apparent as the description proceeds.

In the accompanying drawings, Figure l is a side elevational view partially in vertical section of a heating apparatus with a charging mechanism embodying the features of my invention.

Figs. 2 and 3 are fragmentary detail sectional views taken substantially along lines 2--2 and 33 of Fig. 1.

Fig. 4 is a fragmentary view partially in vertical section, and illustrating the loading mechadapted particularly for various metals, such for K In general, the

example as iron and steel, etc. apparatus comprises a rotary melting furnace 28 which is adapted to receive the metal to be melted at one end and to discharge the molten metal from the other end, and which may be used either for batch or continuous operations; a power driving mechanism 29 for rotating the furnace 28; a fluid pressure operated loading mechanism 30 for charging or catapulting the metal or material to be melted into the inlet end of the furnace 28; and a fuel feeding mechanism 3| for supplying a suitable combustible air-fuel mixture to the furnace 28.

The rotary melting furnace and drive The furnace 28 is elongated and mounted for rotation on its longitudinal axis. The interior thereof constitutes a heating and melting chamber which has a restricted inlet throat 33 at one end, and the other end of which is conical and terminates in a restricted outlet or disiii) charge opening. Preferably, the axis of rotation is slightly inclined out of the horizontal, with the inlet end of th heating chamber uppermost. As a result, the charge indicated at A, tends to feed toward the discharge end.

In its preferred construction, the furnace 28 comprises an outer metallic casing or shell 35 lined internally with a suitable refractory material 36 having insulating properties. The shell 35 consists of an intermediate section 3'! which is cylindrical in form and adapted to be supported in a horizontally inclined position for a rotary drive, a conical discharge end section 38 and an inlet end section 40 in the form of an elongated cylindrical duct and integrally connected by a short conical section ll to the section 31. Suitable gusset plates or braces 42 of varying length are provided to reenforce the shell 35 at the juncture between the sections 3'! and 49. The section 38 is removable to permit lining and repair of the furnace 28.

To retain the refractory material in the tube 40, an annular plate w is secured to an outer peripheral flange 40* on the tube, and overlaps the material.

The inlet throat 33 is defined by the refractory lining, and is elliptical in cross-section. It provides an outlet for fumes and gases of combustion, and an inlet for the iron, ore or other material to be treated or melted. The oval or elliptical form of the throat 33 causes the material to pass to the chamber 28 at the ends of the major axis. The material is preheated in the throat 33, and may in fact be partially or entirely melted therein before actually reaching the chamber 28.

To heat the furnace 28, one or more suitable burners 45 are mounted to discharge into the chamber 28. In the present instance, two powdered fuel burners 45 are mounted in the lined section 4| at opposite ends of the minor aXis tudinally into the chamber 28.

In operation, the material being treated is heated directly by the products of combustion which reverse in flow and pass out through the throat 33. highly heated, and in the rotation of the furnace 28 serves to heat the material.

The furnace 28 may be supported by any suitable means for a rotary drive. In the present instance, this means comprises a rectangular supporting frame 49 which is mounted in an inclined position on an elevated base 50 on a stationary Also, the refractory lining 36 becomes foundation 5|. Rotatably supported in upstanding brackets 52 on the frame 49 at opposite sides of the shell are a plurality of rollers 53. These rollers respectively engage peripherally with two circular rails 54 encircling and secured to opposite ends of the intermediate section 31 of the shell 35, and thereby serve to support the latter. The large end of the conical shell section 38 has an outer peripheral flange 55 which is removably bolted to the lowermost rail 59 to complete the shell assembly. Mounted in the upper end portion of the frame 99 is a thrust bearing 56. A thrust roller 53' is journaled in the bearing 56 on a generally vertical axis, and engages the lower side of the uppermost rail 54 to support the shell 35 against endwise movement, and particularly to maintain the rollers 53 and the rails 54 in proper engagement.

The rotary drive for the furnace 28 is transmitted to the rails 54 through frictional engagement with the rollers 53 at one side which are fixed on a common drive shaft 53. This shaft is connected through gears 59 and 89 to a variablespeed transmission GI driven by an electric motor 62.

The discharge end of the furnace 28, projects through an opening 93 in one side of the base 69 of a stack 69 which serves to carry away fumes from the metal and aiso any products of combustion that may escape through the discharge opening. A plurality of openings 66 with removable covers 57 are provided in the stack base 64. One of these openings 96 (see Fig. l) is substantially in axial alignment with the opening 34 and is therefore conveniently available for charging the furnace by means of a spoon (not shown) with alloys or petroleum carbon or other materials for chan ing the analysis or composition of the finished product. The other openings 66 are located at the opposite sides of the discharge opening, and afford access for various purposes, such for example as the removal of slag tending to clog the discharge opening.

The stack is supported in elevated position by means of hanger bars 88 suspended from a suitable support, such as a roof E3, and the base 64 is flared downwardly and open at the bottom to permit the metal discharging from the opening to pour into a suitable container 19. In the present instance, the container I9 is a large steel ladle or bucket having a discharge spout, and pivotally mounted by means of trunnions 72' on a truck I3. The truck I3 is adapted to be moved on suitable tracks in the foundation 5! into position beneath the stack base 9 To provide means for swinging the ladle I9, a large gear 75 is fixed on one of the trunnion shafts, and meshes with a pinion 16 on a shaft 'll' journaled in the frame of the truck i3 and having a hand wheel 78 fixed thereon. It will be understood that the container 19 is utilized for continuous furnace operation.

The outer end of the duct 59 extends through a flanged opening 89 in the enlarged base 99 of a stack 9| for carrying away gases, fumes and products of combustion from the furnace 23. The base 99 is open at the bottom and mounted in elevated position on a support 92 consisting of a. plurality of I-columns on the foundation 5!. The support 92 is open between the I-columns at the sides and adjacent the furnace 28, and has a wall 93 closing the space between the columns remote from the furnace.

The charging mechanism The charging mechanism 30 is mounted below the stack 9I in position to introduce the material to be treated into the open end of the duct 49 within the stack base 99. In its preferred construction, the charging mechanism 39 comprises an open upright frame 94 which is mounted on the foundation 5!, and supported in a position slightly inclined from the vertical and substantially in the plane of the inlet end of the duct 40. Suitable struts 95, anchored to the elevated base 59, are provided as auxiliary supports for the frame 94.

Mounted on a horizontal rock shaft 96, extending transversely of the furnace 28 and journaled in bearing brackets 9! on the frame 94 is a swinging arm 98. A charging bucket 99 is rigid with the free end of the arm 98, and is adapted to be oscillated or swung thereby from an idle or filling position into an elevated position directly in line with the open end of the duct 40. The idle position is defined by a stop or rest I00 on the foundation 5! for engagement by the bucket 99. When an idle position, the bucket 99 directly underlies a chute IQI mounted in and opening through the wall 93. The elevated position is determined by engagement of an impact head I92, mounted in an intermediate portion of the arm 98, with a fixed stop or plate I93 on the upper end of the frame 94. The head I92 (see Fig. 3) preferably consists of a plunger urged outwardly into an extended position by a coiled compr ssion spring I 94. In its upward movement, the arm 98 comes to a sudden stop when the head I92 engages the plate I93, thereby causing the material in the bucket 99 to be thrown or catapulted into the duct 49.

To provide power means for actuating the bucket 99. When in idle position, the bucket 99 is formed with a concentric arcuate segment I05 Qsee Fig. 2) with a peripheral groove I 06. A rope or cable I07 extends along the groove I06, and is securely anchored at one end to the arm 98 by means of a pin I98. The other end of the cable I9! is connected to a fluid motor, which in the present instance comprises a cylinder I09 mounted in fixed position on the foundation 5| beneath the frame 49, and extending tangentially of the groove I69. A piston is reciprocably disposed in the cylinder I99, and has an elongated piston rod III to which the cable I9! is connected.

Any suitable fluid medium, such as air under pressure, may be supplied under the control of a valve II2 (Figs. 1 and 5) to the cylinder I99 to elevate the bucket 99, and subsequently relieved to permit return of the bucket under the force of gravity into idle position. The valve 12 comprises a body [I3 having a bore I M with peripherally spaced ports H5 to H8. The upper port I I5 is open to a pipe I 59 which may be connected to any suitable source of compressed air (not shown). The side ports H6 and Ill are connected to two pipes I29 and I2! leading respectively to opposite ends of the cylinder I99. The lowerport I I8 is connected to a pipe I22 opening to the atmosphere in the stack base 99. Rotatably adjustable in the bore H6 is a valve member I23 having an actuating shaft I24 and having diametrically opposed land areas i225 and i2? defining intermediate peripheral spaces I2! and I28. Two oppositely extending levers I29 and I39 (Figs. 6 and 7) are fixed on the shaft 24. and carry suspended chains I3I by which the valve may be actuated manually.

The valve member or plug I23 is normally held in neutral position in which the land areas I25 and I26 block the ports H and H8. The means for this purpose comprises a tension spring I32 which is anchored at one end to the pipe H9 and which is connected at the other end to an intermediate chain link I33 anchored at opposite ends to the levers I29 and. I39. In operation, when the valve member I23 is rotated out of neutral in a clockwise direction, air will be supplied freely to the pipe I and the pipe I2! will be connected to the unrestricted exhaust, thereby causing the bucket 99 to be elevated rapidly until the head I92 impinges against the stop I93. in a counterclockwise direction past neutral position will connect the pipe IZI to pressure and the pipe I29 to exhaust to lower the bucket 99. In this position, the land area I26, which is wider than the area I25, covers the port I I8, but establishes the exhaust connection through a restricted bleed passage I34 adapted to throttle the discharge from the pipe I29 so as to cause the return movement of the bucket 99 to be comparatively slow.

To facilitate ease of operation, a counterweight l35 is fixed on the shaft 96. When the bucket 99 is in idle position, the counterweight I35 is located at the opposite side of the shaft 96, and reduces the required lifting power. When the bucket 99 is in elevated position, the counterweight is located forwardly of the shaft 95, and serves to overcome any tendency of the bucket to stay up.

Fuel feeding mechanism The fuel feeding mechanism 3| is adapted to supply a mixture of powdered fuel and air to the burners in all positions of rotation of the furnace 28. The fuel, such ascoal, is supplied from a hopper (not shown) to a pulverizer I31 which is not shown in detail since per se it forms no part of the present invention. It is sufficient to say that the pulverizer I3I has two outlet ducts I38 and I39 of which the first discharges a primary mixture of air and suspended or entrained powdered fuel at a definitely maintained velocity, and the latter is adapted to supply a variable amount of secondary air.

The air duct I 39 has a conical mixing and induction throat I43 at the discharge end, and is connected through an expansion and swivel joint I44 to a fuel duct I45 extending through the base of the stack 9| to the furnace 28. The primary fuel duct I38 is connected to the duct I39 to discharge axially into the throat I43 to complete the ultimate fuel mixture.

The duct I 45 extends through an opening I46 into the stack base 90, and is connected at its discharge end to a distributor I41 mounted on one side of the duct 40 of the furnace 28. It

will be evident that the fuel mixture will be highly preheated in passing through the duct I45.

Movement of the valve member I23 The distributor is connected through two branch lines or flexible tubes I48 to the burners 45. The constructions of the joint I44 and the distributor I41, and the connections of the lines I48 to the burners 45 are more fully described in my said' copending application.

It will be evident that in the rotation of the furnace, the duct I 45 will be revolved thereby about the axis of the coupling I44. Longitudinal expansion and contraction of the duct I 45 are permitted by the coupling I44. To prevent interference between the charging apparatus 30 and the duct I45, means is provided for preventing clockwise adjustment of the control valve II 2 except when the duct is passing through the upper course of its orbital movement. In the present instance, this means comprises a rotary cam I 49 fixed on the duct I45 and adapted for engagement with a roller I59 on the free end of the arm I29. The cam I 49 has an arcuate face extending approximately through and adapted to hold or depress the arm I29 into neutral position. Downward movement is permitted, but this will not effect elevation of the bucket 99. The other half of the cam I49 has an arcuate face of a smaller radius, and when disposed over the arm I29 permits free adjustment of the valve II2 into any selected position.

While I have disclosed the invention as applicable particularly to the melting of metals, it is to be understood that the invention may be utilized for treating various kinds of materials not necessarily involving melting.

I claim as my invention:

Apparatus of the character described comprising, in combination, a support, means defining an intake opening mounted on said support, an arm pivotally mounted at one end on said support and beneath said opening for movement from a substantially horizontal to an upright position, a bucket rigidly carried on the free end of said arm and having a mouth opening upwardly in a substantially horizontal plane when said arm is in its horizontal position and opening laterally to and in substantially coaxial registration with said intake opening when said arm is in its upright position, a concentric arcuate segment formed on the pivoted end of said arm and having a peripheral groove formed therein, a piston and cylinder-type fluid pressure actuator on said support, a cable fixed at one end of said groove and extending therethrough for rigid attachment at its other end to the piston of said actuator for elevating said arm from its horizontal to its upright position upon introduction of pressure fluid to the cylinders, stop means for defining said upright position, yieldable impact means on said arm for engaging said stop means whereby to catapult material contained in said bucket into said intake opening upon such elevation, a counterweight rigidly carried at the pivoted end of said arm and positioned thereon to return said arm and bucket to horizontal position, and control valve means for said cylinder including a restricted orifice for releasing pressure fluid from said cylinder to effect relatively slow return movement of said arm and bucket to horizontal position.

AUBREY J. GRINDLE.

. r. CERTIFICATE OF CORRECTION. Patent No. 2,502,212. I November 17, 191m.

' AUBREY J. GRINDIE.

It is hereby certifiedthat erro'r."eppe ars in the printed specification of theabove numbered patent requiring correction as follows: Page 2, second column,- line 22, for "an idle" read in idle-; line 57, for "bucket n in idle position, the bucket 99" read -bucket 99, the pivoted end-Portion of the arm 98-; and that the said Letters Patent-should be.

read with this correction therein that the same may conform to the record of 'the case in the Patent Office.

Signed and sealed this i2th day of January A. D 1911.5;

Henry Van Arsdale, (Seal, Acting Commissioner of Patents;

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