Title of Invention

GAS SEAL BELL FOR SHAFT FURNACES

Abstract

A gas seal bell for shaft furnaces, in particular blast furnaces, with a product feed hopper having an inward transfer pipe, a rotating chute carrier with rotary drive, and a swiveling chute inside the furnace with driving means situated outside a casing, is made less susceptible to failure and low-wear by having the driving means for swiveling the chute comprise at least one motor (7), which drives a toothed ring (9) via a pinion gear (8) , wherein the toothed ring (9) meshes with the spindle toothed wheels (11) of at least two spindles (13) distributed over the periphery of the gas bell seal outside the rotating chute carrier (3) to generate a lifting and sinking motion of the spindles, along with means (14, 15, 17, 21) for transferring this vertical motion of the spindles to the tilting shafts (22) penetrating the casing wall (24), wherein the chute can be suspended in these tilting shafts, to generate a swiveling or tilting motion of the chute. Figure 1

Full Text

The invention relates to a gas seal bell for shaft furnaces, in particular blast furnaces, with a product feed hopper having an inward transfer pipe, a rotating chute carrier with rotary drive, and a swiveling chute inside the furnace with driving means situated outside a casing. A generic gas seal bell is described in German Patent Application 197 09 329.9. This gas seal bell involves a bell-less gas seal bell, wherein the drives for the rotational and tilting motion of the chute carrier and chute operate independently of each other, and are not connected with the furnace area. The chute carrier mounted in a ball bearing slewing rim has a rotary drive comprised of an electric motor, pinion gear and toothed ring. A hydraulic pressure cylinder that rotates with the chute carrier is disclosed as the driving means for the tilting motion. Placing the tilting drive on the rotating chute carrier of the gas seal bell in this way has proven to be disadvantageous in practice, since a complicated, expensive and failure-prone power transmission to the rotating part is required, e.g., via slip rings. German Laid-Open Patent Specification OS 2404647 describes a device for driving or moving a device used to charge a blast furnace with raw materials. In this case, a distributing delivery chute or chute is connected with the lower ends of an internal cylinder and external cylinder, which are mounted in such a way that they can be simultaneously rotated, axially shifted relative to each other and be independent of each other. The distributing delivery chute can be rotated together with the internal cylinder and external cylinder, and tilted relative to the External cylinder with the vertical motion of the internal cylinder. The vertical motion is initiated with several pressure cylinders. The distributing delivery chute is pivoted at the lower end of the internal cylinder using pintails, and connected with the lower end of the external cylinder by articulated units. The distributing delivery chute is pivoted by vertically moving the external cylinder relative to the internal cylinder. The drive operation described involves a superposed rotational and tilting motion of the chute. Proceeding from the above prior art, the object of the invention is to provide a gas seal bell that is not very susceptible to failure, low-wear and cost-effective. The object is achieved by means of a gas seal bell with the features in claim 1. The sub claims disclose advantageous embodiments. Gas seal, bellfor shaft furnaces, in particular blast furnaces, with a product feed hopper having an Inward transfer pipe, a rotating chute carrier with rotary drive, and a swiveling chute inside the furnace with driving means situated outside a casing, characterized by the fat that the driving means for swiveling the chute (i) comprise: - at least one motor (7), which drives a toothed ring (9) via one pinion gear (8) each, - wherein the toothed ring (9) engages the spindle toothed wheels (11) of at least two spindles (1.3) distributed over the periphery of tine gas bell seal outside the rotating chute carrier (3) to generate a lifting and sinking motion of the spindles, - and means (14,15,17,21) for conveying this vertical motion of the spindles to tilting shafts (22) penetrating the casing wall (24), wherein the chute can be suspended in these tilting shafts, to generate a swiveling or tilting motion of the chute. By way of a solution, it is proposed that the driving means for swiveling the chute consist of at least one motor, preferably two motors, which drives a toothed ring via a pinion gear, wherein the toothed ring meshes with the spindle toothed wheels of at least two spindles distributed over the periphery of the gas bell seal outside the rotating chute carrier to generate a lifting and sinking motion of the spindles, along with means for transferring this vertical motion of the spindles to the tilting shafts penetrating the casing wall, wherein the chute can be suspended in these tilting shafts, to generate a swiveling or tilting motion of the chute in this way, it Is possible to overcome the disadvantages of a concurrently rotating drive for the tilting motion of the chute while reaping the advantages of a separate arrangement of the two drives for the rotational and tilting motion of the chutes. In contrast to the solution known from German Patent Application 197 09 329.9, the actual driving means for generating the tilting motion of the chute no longer rotate concurrently. The spindles are rigidly secured to the gas bell seal. Only parts of the less failure-prone motion transfer means rotate. In comparison to the solution according to OS 2404647, a precise synchronism is achieved for the lifting devices, so that canting or jamming is no longer possible. The motion transfer means between the spindles and chute involve a lifting frame and lifting ring, wherein the vertical motion of the spindle nut entrains the lifting frame, and the vertical motion of the lifting frame entrains the lifting ring. Articulated units are secured to the lifting ring, converting the lifting and sinking motion of the lifting ring into a corresponding rotational motion of the tilting shafts by eccentrically engaging the tilting shafts. To this end, the first end of the tilting shafts has means for suspending the chute, while their second end has an area extending at a right angle to the shaft axis for connection with the articulated units. In a particularly preferred embodiment, three spindles are provided, which ensure a driving operation especially free of canting. The arrangement of driving means according to the invention and selection of drives enables a complete synchronism for the lifting spindles, and hence an absolutely uniform, unwanted lifting and sinking of the lifting ring, and hence a low susceptibility to failure. To ensure a low level of wear, it is proposed that the driving means for the rotational and swiveling motion of the chute carrier or chute be sealed off with a hood placed on the casing. The resultant internal space is preferably filled with nitrogen. In this way, the driving elements remain dust-free, which has an advantageous effect on their service life. While the driving means are not as readily accessible, the used seals are no longer subjected to the full pressure differential between the gas pressure at the furnace end and atmospheric pressure. The hood solution makes it possible to use nitrogen for building up a gas pressure inside the casing that somewhat exceeds the pressure inside the furnace. The pressure can be automatically readjusted. Then, the seals known from German Patent Application 197 09 329.9 can be made less expensively. Additional details of the invention are given in the following description. Shown on: Fig. 1 is a side view of the gas seal bell; Fig. 2 is a front view of the gas seal bell. Fig. 1 shows a gas seal bell with rotating and tilting chute 1 for loading a blast furnace. The charge is transferred out of an inward transfer bunker {not shown) into a product feed hopper situated under the latter (not shown) . The charge moves from the product feed hopper through an inward transfer pipe 2 to a tilting and rotating chute 1 situated inside the chute carrier, and from there into the top portion of the furnace. The chute carrier 3 with chute is made to rotate by a rotary drive comprised of a motor 4, a pinion gear 5 and a toothed ring 6. Another motor 7 that drives a toothed ring 9 via a pinion gear 8 is provided for the tilting motion. The drive elements are mounted by means of bearing 10. The toothed ring 9 drives the respective spindle toothed wheel 11 from three spindles distributed over the periphery of the gas bell seal casing 12. The rotational motion causes the spindle nut to lift and sink, taking the adjacent lifting frame 14 along. The lifting ring 15 is situated next to the lifting frame. The vertical motion of the lifting frame 14 is imparted to the lifting ring 15, while a bearing 16 situated laterally below the lifting ring takes up the rotational motion of the lifting ring. The first end IS of articulated units 17 are detachably secured and mounted on the lifting ring 15. The second end 20 of the articulated units 17 is detachably secured to a connecting part 21 of the tilting shafts 22. The articulated units 17 engage the connecting part 21 of the tilting shafts 22 eccentrically, so that the vertical motion of the lifting ring 15 is converted into a corresponding rotational motion of the tilting shafts 22. The tilting shafts 22 are mounted in bearings 23. They penetrate the wall of the casing 24 in a gastight manner. The inwardly pointing end 28 of the tilting shafts 22 is designed in such a way that the rotating chute 1 can be suspended. In this case, the chute 1 can advantageously be latched for safety reasons using short lifting cylinders 25. The upper and lower annular seals are labeled 26 and 27. A hood can be used to lock the casing 12 and driving means, and make them gastight. The inside pressure can be controlled by feeding in nitrogen. We claim, 1. Gas seal bell, for shaft furnaces, in particular blast furnaces, with a product feed hopper having an inward transfer pipe, a rotating chute carrier with rotary drive, and a swiveling chute inside the furnace withdrivingmeans situated outside a casing, characterized by the fat that the driving means for swiveling the chute (1) comprise: - at least one motor (7), which drives a toothed ring (9) via one pinion gear (8) each, - wherein the toothed ring (9) engages the spindle toothed wheels (11) of at least two spindles (13) distributed over the periphery of the gas bell seal outside the rotating chute carrier (3) to generate a lifting and sinking motion of the spindles, - and means (14,15,17,21) for conveying this vertical motion of the spindles to tilting shafts (22) penetrating the casing wall (24), wherein the chute can be suspended in these tilting shafts, to generate a swiveling or tilting motion of the chute. 2. Gas seal bell as claimed In claim 1, wherein the motion transfer means comprise a lifting frame (14) and lifting ring (15), wherein the vertical motion of the spindle nut entrains the lifting frame (14), and the vertical motion of the lifting frame (14), and the vertical motion of the lifting frame entrains the lifting ring (15), as well as articulated units (17), which are secured to the lifting ring (15), converting the lifting and sinking motion of the lifting ring into a corresponding rotational motion of the tilting shafts by eccentrically engaging the tilting shaft (22). 5. Gas seal bell as claimed in claim 2, wherein the first end (28) of the tilting shaft (22) has means for suspending the chute (1), while their second end has an area (21) extending at a right angle to the shaft axis for connection with the articulated units (17). 4. Gas seal bell as claimed in claim 1 or 2, wherein the driving means for the rotational and swiveling motion of the chute carrier or chute can be sealed off with a hood and the internal space can be filled with a gas. 5. Gas seal bell as claimed in claim 1, wherein there spindles (13) are provided. 6. Gas seal bell as claimed In claim 2, wherein a bearing (16) is arranged laterally below the lifting ring (15) to take up the rotational motion of the lifting ring. 7. Gas seal bell as claimed in one of the preceding claims, wherein the rotary drive consists of a motor (4), pinion gear (5) and toothed ring (6). 8. Gas bell seal for shaft furnaces substantially as herein described with reference to the accompanying drawings.

Documents:

in-pct-2001-0894-che abstract.jpg

in-pct-2001-0894-che abstract.pdf

in-pct-2001-0894-che assignment.pdf

in-pct-2001-0894-che claims.pdf

in-pct-2001-0894-che correspondence-others.pdf

in-pct-2001-0894-che correspondence-po.pdf

in-pct-2001-0894-che description (complete).pdf

in-pct-2001-0894-che drawings.pdf

in-pct-2001-0894-che form-1.pdf

in-pct-2001-0894-che form-13.pdf

in-pct-2001-0894-che form-19.pdf

in-pct-2001-0894-che form-26.pdf

in-pct-2001-0894-che form-3.pdf

in-pct-2001-0894-che form-5.pdf

in-pct-2001-0894-che form-6.pdf

in-pct-2001-0894-che pct.pdf

in-pct-2001-0894-che petition.pdf

in-pct-2001-894-che-abstract.jpg