Title of Invention

"A DEVICE FOR METERING MATERIALS"

Abstract

A device for metering materials, comprising: a first (18) and a second (20) rotating gate; shafts (24, 26) arranged at each side of the gates (18, 20) to support the two gates (18, 20) and allow them to rotate around a common axis of rotation (25), a first (24) of said shafts being arranged at one side of the two gates (18, 20) and a second (26) of said shafts being arranged at the other side; and a drive mechanism connected to the shafts (24, 26) to turn the two gates (18, 20) in opposite directions; said first shaft (24) and said second shaft (26) being actuated in different directions by said drive mechanism; characterised in that each rotating gate (18, 20) is supported by a first suspension arm (28, 30) and by a second suspension arm (32, 34) which extend from each side of the respective gate; in that said first suspension arm (28) of said first gate (18) is fastened detachably to said first shaft (24); in that said first suspension arm (30), or said second gate (20) is fastened detachably to said second shaft (26); in that said second suspension arm (32) of said second gate (20) is connected to and articulated on said first suspension arm (28) of said first gate; and in that said second suspension arm (34) of said first gate (18) is connected to and articulated on said first suspension arm (30) of said second gate (20).

Full Text

FORM 2 THE PATENTS ACT, 1970 (39 of 1970) COMPLETE SPECIFICATION (See section 10; rule 13) A DEVICE FOR METERING MATERIALS PAUL WURTH S.A., OF 32, RUE D'ALSACE , L-1122 LUXEMBOURG, LUXEMBOURG The following specification particularly describes the nature of this invention and the manner in which it is to be performed P-PWU-428/WO Device for metering bulk materials The present invention concerns a device for metering bulk materials, in particular for charging a blast furnace. A metering means of this kind for bulk materials is disclosed, for example, in patent application EP-A-0 062 770, where it is fitted to the outlet of 5 a storage hopper mounted at the top of a shaft furnace. It is arranged concentrically with the axis of the furnace and comprises, inside a closed housing, two gates one above the other in the form of spherical segments with V-shaped cut-outs. The two gates are supported at one end on the same pivot shaft, around which they can turn freely. This pivot shaft is supported in a first 10 bearing in the closed housing. On the side diametrically opposite this first shaft, a shaft, integral with the upper gate, is located inside and concentric with a quill shaft integral with the lower gate. The quill shaft is supported in a second bearing in the closed housing. A drive mechanism mounted outside the closed housing actuates the two concentric shafts so that the two gates are moved 15 synchronously in opposite directions. Such a drive mechanism is described, for example, in patent application EP-A-0 134 918. When the two gates are actuated synchronously in opposite directions, the two cut-outs act together to define and vary the cross-section of the outlet, thereby allowing material to discharge symmetrically around the axis of the 20 furnace. However, such a metering means is bulky and replacing the gates is complicated. The gates in the charging equipment of a shaft furnace are clearly wear parts that need to be replaced from time to time, hence the interest in facilitating their replacement. The object of the present invention is thus to propose a metering device 25 with easily replaceable gates. Under the invention, this objective is met by a metering device in accordance with claim 1. A materials metering device in accordance with the invention comprises P-PWU-428/WO a first and a second rotating gate. Shafts on each side of the gates support the two gates and allow them to rotate around a common axis of rotation. The first of these shafts is arranged at one side of the two gates, and the second is arranged at the opposite side. A drive mechanism is connected to the shafts to 5 turn the two gates in opposite directions. According to one important aspect of the invention, each rotating gate is supported by a first suspension arm and by a second suspension arm on each side of the respective gate. The first shaft and the second shaft are driven in opposite directions by the drive mechanism. The first suspension arm of the first gate is fastened detachably to the first 10 shaft, and the first suspension arm of the second gate is fastened detachably to the second shaft. The second suspension arm of the second gate is connected to and articulated on the first suspension arm of the first gate, and the second suspension arm of the first gate is connected to and articulated on to the first suspension arm of the second gate. This results in a gate unit that can be 15 removed en bloc and thus easily replaced. To remove the gate unit en bloc, all that needs to be done is detach the suspension arm of the first gate from the first shaft, and the first suspension arm of the second gate from the second shaft. The gate unit can then be removed, either upwards or downwards. According to a preferred embodiment, the first suspension arm of the first 20 gate comprises a first mounting flange and the first shaft comprises a first counter-flange. The first flange is fastened detachably face to face to the said first counter-flange. In addition, the first flange comprises a first trunnion extending from the side opposite said first counter-flange. The second arm of the second gate is articulated on said first trunnion. In a similar way, the first 25 suspension arm of the second gate comprises a second mounting flange and the second shaft comprises a second counter-flange. The second flange is fastened detachably face to face to said second counter-flange. In addition, the second flange comprises a second trunnion extending from the side opposite P-PWU-428AVO said second counter-flange. The second arm of the first gate is articulated on said second trunnion. Thanks to the flanges and counter-flanges, the first arms of each gate can be quickly detached from their respective shafts. All that needs to be done is detach the flange and counter-flange, for example by undoing the 5 bolts, to remove the gate unit upwards or downwards. Advantageously, an axial space can be provided on the first trunnion between the second arm of the second gate and the first arm of the first gate. Similarly, an axial space can be provided on the second trunnion between the second arm of the first gate and the first arm of the second gate. On removal of 0 the gates, the two first suspension arms can be pushed towards each other, sliding them along their respective trunnions This reduces the axial space and creates a clearance between the flanges and counter-flanges, which facilities removal of the gate units. In a particularly simple embodiment, the gates are no longer in the form 5 of spherical segments, but cylindrical segments, with a cut-out of a suitable shape, for example a V-shaped cut-out. The gates in the form of a cylindrical segment are preferably associated with an outlet channel that they completely block when in the closed position. In this closed position, the gates partially overlap each other and are situated just !0 below the lower edge of the outlet channel. This lower edge is shaped like a stepped cylinder, which follows the shape of the two partially overlapping gates. In the closed position, the material is therefore unable to flow out from the outlet channel. According to a preferred embodiment, the drive mechanism comprises a !5 main shaft and two connecting rods. The two shafts each comprise a crank, and the connecting rods link the main shaft to the cranks in such a way that two rotations are produced, in opposite directions. The use of one main shaft linked to two shafts has the advantage of producing synchronous rotation of the two shafts. The rotation of the main shaft around its longitudinal axis can be 10 produced by a hydraulic cylinder, for example, which allows accurate and direct P-PWU-428AVO actuation of the rotation in one direction or the other, depending on whether the cylinder is extending or retracting. Other features and characteristics of the invention can be seen from the detailed description of one advantageous embodiment set out below by way of 5 illustration, with references to the attached drawings. These show: Figure 1: a perspective view of a preferred embodiment of a metering device with gates, in accordance with the invention; Figure 2: a partial section of the suspension of the gates of the device in Figure 1; 10 Figure 3: a rear view of the device in Figure 1, during removal; Figure 4: a rear view of the device in Figure 1, showing a drive mechanism for the gates; Figure 5: the assembly in Figure 4, viewed from the left; Figure 6: the assembly in Figure 4, viewed from the right; 15 Figure 7: a section view of the metering device in Figure 1, in the closed position; Figure 8: a section view of the metering device in Figure 1, in the open position. The references in the Figures relate to the same or identical elements in 20 each Figure. Figure 1 shows a perspective view of a preferred embodiment of a metering device 10 for bulk materials in accordance with the invention. A wear cone 12 of a storage chamber 14 ends in a cylindrical outlet channel 16 placed upstream of and above the shaft furnace (not shown). The metering device 10 25 is arranged under the storage chamber 14, in a closed housing 17 (represented by two parts of the wall), situated between the storage chamber 14 and the furnace. It comprises, underneath the bottom end of the cylindrical outlet channel 16, a first or upper gate 18 and a second or lower gate 20, situated under the upper gate 18 (see also Figure 7). Two shafts 24 and 26, arranged at P-PWU-428AVO each side of the gates 18 and 20, support the latter and allow them to rotate around a common axis of rotation 25 (see also Figure 3). A drive mechanism, not shown in Figure 1, but referenced as an assembly as 27 in Figures 4 to 6, drives the two shafts 24 and 26 synchronously in opposite directions, so that 5 two V-shaped cut-outs 22 in the gates 18 and 20 form a central lozenge-shaped outlet opening between the two gates 18 and 20. It will be noted that in Figure 1, cut-out 22 of upper gate 18 is overlapped by lower gate 20. In these positions of gates 18 and 20, the metering device 10 is in the closed position, completely preventing any discharge of material from outlet channel 16. 10 Each gate 18 and 20 is supported by a first suspension arm and a second suspension arm, which extend from one side to the other of the respective gates. The first suspension arm 28 of upper gate 18 is mounted detachably on the first shaft 24. The first suspension arm 30 of lower gate 20 is mounted detachably on the second shaft 26. The second suspension arm 32 of 15 lower gate 20 is articulated on the first suspension arm 28 of upper gate 18, while the second suspension arm 34 of upper gate 18 is articulated on the first suspension arm 30 of lower gate 20. The drive mechanism actuates the two shafts 24 and 26 in opposite directions, which allows the two gates to open and shut. 20 Figure 2 shows a partial section of the end of the second shaft 26. The first suspension arm 30 of lower gate 20 ends in a mounting flange 36 which is fastened detachably, for example by means of a bolted joint, to a counter-flange 38 on the second shaft 26. Flange 36 comprises a trunnion 40 which extends from the side opposite counter-flange 38 and which supports the second 25 suspension arm 34 of upper gate 18 so that it is articulated. Flange 36 and counter-flange 38 are executed in the form of two vertical fixed flat surfaces mounted face to face. Trunnion 40 is sited in the centre of flange 36 concentric with the second shaft 26. The second suspension arm 34 of the upper gate 18 ends in a suspension boss 42 with a bore through which trunnion 40 passes, so 30 that it is articulated on this trunnion 40. A bush 44 reduces friction. P-PWU-428/WO On the other side, at the first shaft 24, the assembly is similar (see Figure 3). The first suspension arm 28 of the upper gate 18 ends in a mounting flange 46 fastened to a counter-flange 48 of the first shaft 24. The flange 46 comprises a trunnion 50 which extends from the side opposite the counter-flange 48 and 5 which supports second suspension arm 32 of the lower gate 20 so that it is articulated. The second suspension arm 32 of the lower gate 20 ends in a suspension boss 52 with a bore fitted with a bush through which the trunnion 50 passes. In this way, each gate 18 and 20 is supported by a first suspension arm 10 ending in a flange, and a second suspension arm ending in a support boss. Although a first arm of a gate is actuated by one of these shafts, the same first arm supports the second arm of the other gate so that it is articulated. This assembly gives a visual impression of the first suspension arm of one gate crossing the second suspension arm of the other gate. 15 Removal of the gates 18 and 20 of the present metering device is very simple. All that needs to be done is to detach, for example by unbolting, each flange 36 and 46 from its respective counter-flange 38 and 48, in order to detach completely each first suspension arm 28 and 30 from its respective shaft 24 and 26. Suspension arms 28, 30, 32 and 34, with the gates 18 and 20 thus 20 form a gate unit that can be removed as it is, through either the top or the bottom of the closed housing 17. An axial space can be seen on trunnion 40 in Figure 2 between the flange 36 of the first suspension arm 30 of the lower gate 20, and the support boss 42 of the second suspension arm 34 of the upper gate 18. This space is 25 matched by an equal space on the other side, on trunnion 50 of flange 46 of the first suspension arm 28 of the upper gate 18. Once the flanges are detached from the counter-flanges, the first suspension arms 28 and 30 are pushed towards each other to reduce the space between the flanges and support bosses. This results in a clearance between the counter-flanges of the two P-PWU-428AVO shafts, and the gate assembly, that is, the suspension arms with the gates, can be manoeuvred more easily. This clearance is indicated with the letter X in Figure 3, which shows a rear view of Figure 1. The wear cone 12 has been removed for disassembly. A 5 lifting beam 54, fitted with two lateral hooks 56, enables the assembly of the first and second suspension arms 28, 30, 32 and 34 and the gates 18 and 20 to be removed upwards. Only the first arms 28 and 30 have been unbolted, then pushed towards each other. Shafts 24 and 26 are still in position. The second arms 32 and 34 slide on trunnions 50 and 40 respectively. 10 Figure 4 is another view of the metering device 10, showing the drive mechanism. In order for the shafts 24 and 26 to be able to rotate, they are each supported by a rolling contact bearing 58 mounted in the wall of the closed housing 17. Only the part of each shaft 24, 26 ending in the counter-flange 38, 48 is situated inside the closed housing 17, the rest extends outside the housing 15 17. A main shaft 60, supported in bearings 62 outside the closed housing 17, runs along the entire width of the metering device 10 and actuates the rotation of shafts 24 and 26 by means of systems of cranks and connecting rods. Cranks 64 and 66 at the end of each shaft 24 and 26 respectively connect each shaft to the end of connecting rods 68 and 70 respectively, see Figures 5 and 6. 20 The other ends of connecting rods 68 and 70 respectively are linked to main shaft 60 by main cranks 72 and 74 respectively. A hydraulic cylinder 76 is connected to main shaft 60 by means of an actuator crank 78 and rotates main shaft 60 in both directions around its longitudinal axis. It is clear that hydraulic cylinder 76 can be replaced by other drive means, for example a rotating motor. 25 The drive mechanism is controlled so that rotation of the main shaft 60 produces rotation of the gates 18 and 20 in opposite directions. When this rotation occurs, the two V-shaped cut-outs together define a central lozenge-shaped outlet opening, the cross-section of which varies progressively. Figures 5 and 6 show views from the left and right respectively of the assembly shown P-PWU-428/WO in Figure 4. The gates 18 and 20 are in the closed position. As can be seen, elongation of the cylinder produces clockwise rotation of the main shaft, viewed from the end in Figure 5, which causes crank 64 and upper gate 18 to rotate clockwise, as shown by the arrows. Consequently, the rotation of the main shaft 5 60 seen in Figure 6 is anti-clockwise. Crank 66 and lower gate 20 are actuated in a clockwise direction, as shown by the arrows. The two gates 18 and 20 are thus opened synchronously in opposite directions. In order to facilitate disassembly using lifting beam 54, the support boss 42 of the second suspension arm 34 of the upper gate 18 is fitted with a 10 handling lug 80, as can be seen in Figure 2. This handling lug 80 comprises a bore 82 which, when the metering device 10 is in the closed position, is aligned with a bore (not shown) in flange 36. Inserting a locking bar (not shown in Figure 2) into these two bores blocks the relative movement between the first and second suspension arms 30 and 34 respectively, and the two gates 20 and 15 18 respectively. As can be seen in Figure 3, the part of the locking bar situated between support boss 42 and flange 36 can act as an anchoring point for the hook 56 of the lifting beam 54. A handling lug of this kind can equally be provided on the other support boss 52, at the end of the first shaft 24. A shoulder 84 on trunnion 40 prevents the boss 42 from abutting against the 20 flange 36 when the two first arms 28 and 30 are pushed towards each other, and thus maintains an anchorage point for a hook 56 of lifting beam 54. It will equally be noted that the entire drive mechanism is situated outside the closed housing 17. In fact, only the first, 28 and 30, and second, 32 and 34, suspension arms, gates 18 and 20, and the parts of shafts 24 and 26 forming 25 the counter-flanges 38 and 48, are situated inside the closed housing 17 and exposed to the atmosphere prevailing inside the furnace. Figures 7 and 8 show a partial section of Figure 1 along the wear cone 12, perpendicular to the common axis of rotation indicated by the reference 86. P-PWU-428/WO In Figure 3, the metering device 10 is in the open position. It can be seen that the lower edge of the channel 16 defines two cylindrical surfaces 88 and 90, the centres of which are coincident with the common axis of rotation 25, but which have different radii of curvature. The radius of the first cylindrical surface 88 is 5 slightly less than the radius of the interior curvature of cylindrical segment 18. The radius of the second cylindrical surface 90 is slightly less than the radius of the interior curvature of cylindrical segment 20. In this way, the lower edge of channel 16 closely follows the interior shape of the two gates 18 and 20 when the latter partially overlap each other when in the closed position, as shown in 10 Figure 7. Consequently, the material cannot flow out between the lower gate 20 and the lower edge of the channel 16. It will also be noted that in order to compensate for the difference in length between suspension arms 30 and 32 of the lower gate 20, and suspension arms 28 and 34 of the upper gate 18, the common axis of rotation is 15 offset laterally in relation to the central axis 92 of the channel 16, towards the upper gate 18. This has the effect of making the device more compact when in the open position. Similarly, it will also be noted that the lower gate 20 must swing through a greater arc than the upper gate 18. These different arcs of the two gates 18 and 20 are defined, for example, by different lengths of the levers 20 64 and 66. Claim: - A device for metering materials, comprising: a first (18) and a second (20) rotating gate; shafts (24, 26) arranged at each side of the gates (18, 20) to support the two gates (18, 20) and allow them to rotate around a common axis of rotation (25), a first (24) of said shafts being arranged at one side of the two gates (18, 20) and a second (26) of said shafts being arranged at the other side; and a drive mechanism connected to the shafts (24, 26) to turn the two gates (18, 20) in opposite directions; said first shaft (24) and said second shaft (26) being actuated in different directions by said drive mechanism; characterised in that each rotating gate (18, 20) is supported by a first suspension arm (28, 30) and by a second suspension arm (32, 34) which extend from each side of the respective gate; in that said first suspension arm (28) of said first gate (18) is fastened detachably to said first shaft (24); in that said first suspension arm (30), or said second gate (20) is fastened detachably to said second shaft (26); in that said second suspension arm (32) of said second gate (20) is connected to and articulated on said first suspension arm (28) of said first gate; and in that said second suspension arm (34) of said first gate (18) is connected to and articulated on said first suspension arm (30) of said second gate (20). 2. Device as claimed in claim 1, wherein the said first suspension arm (28) of said gate (18) has a first mounting flange (46), and said first shaft (24) has a first counter-flange (28), and first flange (46) being fastened detachably to said counter-flange (48); the said first flange (46) has a first trunnion (50) extending from the side opposite said first counter-flange (48), said second suspension arm (32) of said second gate (20) being articulate on said first trunnion (50). 3. Device as claimed in claim 1, wherein the said first suspension arm (30) of said second gate (20) has a second mounting flange (36) and said second shaft (26) has a second counter-flange (38), said second flange (36) being fastened detachably to said second counter-flange (38); the said second flange (36) has a second trunnion (40) extending from the side opposite said second counter-flange (38), said second suspension arm (34) of said first gate (18) being articulated on said second trunnion (40). 4. Device as claimed in claim 2 or 3, wherein an axial space on said first trunnion (50) between said second suspension arm (32) of said second gate (20) and said first suspension arm (28) of said first gate (18) respectively, by an axial space on said second trunnion (40) between said second suspension arm (34) of said first gate (18) and said first suspension arm (30) of said second gate (20). 5. Device as claimed in any of the above claims, wherein said gates (18, 20) are in the shape of a cylindrical segment. 6. Device as claimed in any of the above claims, wherein: the drive mechanism has a main shaft (60) and two connecting rods (68, 70); the two shafts each comprise a crank (64, 66); said connecting rods (68, 70) connecting said main shaft (60) to said cranks (64, 66) in such a way as to produce two rotations in opposite directions. 7. Device as claimed in claim 6, wherein the drive mechanism has a hydraulic cylinder (76) to cause the rotation of the main shaft (60) about its longitudinal axis. 8. Device as claimed in claim 5, having an outlet channel (16) with a lower edge, wherein said gates (18, 20) have a closed position in which they partially overlap each other just below the lower edge of outlet channel (16), said lower edge having a stepped cylindrical shape which closely follows the shape of the two partially-overlapping gates. Dated this the 25th day of February, 2002 [JAYANTA PAL] Of Remfry & Sagar ATTORNEY FOR THE APPLICANTS]

Documents:

abstract1.jpg

IN-PCT-2002-00237-MUM-ABSTRACT(25-2-2002).pdf

in-pct-2002-00237-mum-assignment(19-11-2004).pdf

IN-PCT-2002-00237-MUM-CANCELLED PAGES(19-11-2004).pdf

in-pct-2002-00237-mum-claims(25-2-2002).pdf

in-pct-2002-00237-mum-claims(amended)-(19-11-2004).pdf

in-pct-2002-00237-mum-claims(granted)-(14-8-2007).pdf

in-pct-2002-00237-mum-claims(granted)-(19-11-2004).doc

in-pct-2002-00237-mum-claims(granted)-(19-11-2004).pdf

in-pct-2002-00237-mum-correspondence(19-09--2007).pdf

in-pct-2002-00237-mum-correspondence(ipo)-(08-01-2004).pdf

in-pct-2002-00237-mum-correspondence(ipo)-(28-8-2007).pdf

in-pct-2002-00237-mum-declaration(25-02-2005).pdf

in-pct-2002-00237-mum-description(complete)-(25-2-2002).pdf

in-pct-2002-00237-mum-description(granted)-(14-8-2007).pdf

in-pct-2002-00237-mum-drawing(19-11-2004).pdf

in-pct-2002-00237-mum-drawing(25-2-2002).pdf

in-pct-2002-00237-mum-drawing(granted)-(14-8-2007).pdf

in-pct-2002-00237-mum-form 1(25-02-2002).pdf

IN-PCT-2002-00237-MUM-FORM 1(25-2-2002).pdf

in-pct-2002-00237-mum-form 13(19-9-2007).pdf

in-pct-2002-00237-mum-form 19(06-11-2003).pdf

in-pct-2002-00237-mum-form 1a(19-09-2007).pdf

in-pct-2002-00237-mum-form 1a(19-11-2004).pdf

in-pct-2002-00237-mum-form 2(25-2-2002).pdf

in-pct-2002-00237-mum-form 2(granted)-(14-8-2007).pdf

in-pct-2002-00237-mum-form 2(granted)-(19-11-2004).doc

in-pct-2002-00237-mum-form 2(granted)-(19-11-2004).pdf

in-pct-2002-00237-mum-form 2(title page)-(25-2-2002).pdf

in-pct-2002-00237-mum-form 2(title page)-(granted)-(14-8-2007).pdf

in-pct-2002-00237-mum-form 3(19-11-2004).pdf

in-pct-2002-00237-mum-form 3(25-2-2002).pdf

in-pct-2002-00237-mum-form 5(25-02-2002).pdf

in-pct-2002-00237-mum-form-pct-isa-210(25-02-2002).pdf

in-pct-2002-00237-mum-petition under rule 137(05-01-2005).pdf

in-pct-2002-00237-mum-petition under rule 137(19-11-2004).pdf

in-pct-2002-00237-mum-power of authority(18-03-2002).pdf

IN-PCT-2002-00237-MUM-POWER OF AUTHORITY(21-5-2002).pdf

in-pct-2002-00237-mum-wo international publication report(25-2-2002).pdf