Title of Invention

SLIDING GATE VALVE FOR A VESSEL CONTAINING MOLTEN METAL

Abstract

A sliding gate valve for a vessel containing molten metal has a push rod (27), which is associated with a slider unit longitudinally guided in a slider housing, which slider unit may be connected by means of a coupling (40) with a drive rod (32) of a linear actuator (30), a mounting (28) for receiving the linear actuator (30) being provided on the slider housing. The coupling (40) is so constructed that it automatically couples, when the linear actuator (30) is slid into the mounting (28), by virtue of movement of the drive rod (32) towards the slider unit (25) and this coupling (40) automatically decouples when the linear actuator (30) is removed from the mounting (28) transversely to the direction of movement of the drive rod (32). The one coupling portion of the coupling (40) has claw elements (41,42) which are spread outwardly during the coupling process along guide surfaces (43’) on the other coupling portion (43) until they automatically snap in at it and engage around it in a form-locking manner.

Full Text

The invention relates to a sliding gate valve for a vessel containing a molten metal including a slider unit,which is longitudinally guided in a slider housing and has a push rod and which may be connected via a couping to a drive rod of a linear actuator, a mounting for receiving the linear actuator being provided on the slider housing. In a known device for actuating a sliding gate valve disclosed in the publication EP-A-011028, a coupling is provided on the one hand for flange connecting a linear actuator, constructed as a piston-cylinder unit, to a fixed slider portion, and on the other hand a coupling is arranged for releasably connecting the movable slder portion to the piston rod of the actuator. The coupling for the flange connection of the linear actuator is constructed as a bayonet connector in which the piston-cylnder unit is pushed in the direction of its axis of movement into the fixed sider portion and subsequently secured therein by rotation. This manoeuvre is, however, not practical since this piston-cylinder unit Is of very heavy construction. The couping for the releasable connection of the movable slider portion to the piston rod is so constructed that by moving the piston rod an element on Is front engages in a coupling element on the slider unit and a connection is produced when the cylinder is rotated. This is again retant on laborious rotation of the cylinder. Against this background, it is the object of the present invention to provide a sliding gate valve with a couping of the type referred to above, by means of which as simple as possible manipulation is made possible for the positioning or removal of the linear actuator and for the coupling and decoupling of its drive rod to and from, respectively, the slider unit. The object is solved in accordance with the invention if the couping is so constructed that when the linear actuator is slid into the mounting it automatically couples as a result of movement of the drive rod towards the slider uni and this coupling automatically decouples when the linear actuator is removed from the mounting transverse to the direction of movement of the drive rod. With this coupling in accordance with the invention, a linear actuator can be positioned in the mounting on the sliding gate valve and couping of the drive rod with the slider unit and similarly decouping and removal of the linear actuator can be performed in a most simple manner. In a preferred embodiment the couping has a couping portion on the end of the drive rod of the linear actuator which has at least one, preferably two, pivotelly mounted clew elements which, in the coupled state, engage around the other fiange-like coupling portion on the end of the push rod of the slider unit. An exemplary embodiment and further advantages of the invention wil be explained in more detail with reference to the drawings, in which: Fig. 1 is a longitudinal sectional view of a vessel which is shown only in part and of a sliding gate valve with a coupling in accordance with the invention, Fig. 2 is a longitudinal sectional view of the linear actuator and of the coupling in the decoupled state, Fig. 3 is a longitudinal sectional view of the coupling and of the linear actuator on the line Il-ll in Fig. 2. Fig. 4 is a longitudinal sectional view of the linear actuator, the mounting and the couping during the couping process, Fig. 5 is an enlarged sectional view of the couping of Fig. 3. Fig. 6 is a longitudinal sectional view of the linear actuator and of a modified coupling in the coupled sate, and Fig. 7 is a sectional view of the coupling on the Ine VII-VII in Fig. 6. Fig. 1 shows a sliding gate valve 20 on a vessel containing molten metal which is shown in part and is constructed in the present case as a so-called ladle 10. This ladle 10 has an outer steel shell 11 in the conventional manner, a refractory lining 12 embedded In it and an outlet 14, which Is constituted by a refractory nozzle brick 15 and a refractory sleeve 16. Disposed at the outlet 14 is a sliding gate valve 20 which substantially comprises a housing upper portion 21 with a refractory base plate 23 inserted therein, a housing frame 22 and a slider unit 25, which is releasably clamped in it, with a refractory sliding plate 24 and a discharge sleeve 26 connected thereto. The outlet 14 can be moved from the llustrated open posltion Into a throttled or closed position by longitudinal movement of the slider unit 25 and of the slider plate 24 inserted in it. Such a sliding gate valve 20 is know per se and described in detail In, for instance, publication EP-BMJ277146 and will thus not be described below in all its details. The slider unit 25 is connected for back and forth movement to a Nnear actuator 30, constructed as a hydraulic piston/cylnder unit, via a push rod 27 and a coupling 40. The liner actuator is for its part removably secured in a mounting 28 which is flange connected to the housing upper portion 21. The linear actuator 30 is commonly left on the pouring; platform of a continuous casting installation, in contrast to the ladle 10. It is thus installed on the ladle 10, which is filled with molten steel and equipped with the closed sliding gate valve 20, when the ladle 10 has been brought onto the pouring platform. Alter emptying the ladle, the linear actuator 30 is removed from it again so that the ladle 10 can be transferred by means of a crane away from the pouring platform again to a ladle station or the like and refilled with molten steel. For the purpose of simple instalation and removal from the ladle, the linear actuator 30 is arranged in a manner known per se to be slidable transverse to the direction of movement of its drive rod 32 into and out of this mounting 28. After siding I in, its drive rod 32 is coupled via a coupling 40 to the push rod 27 of the slider unit 25 in coaxial alignment wlh It. In accordance with the invention, the coupling 40 is so constructed that when the linear actuator 30 is slid into the mounting 28, I couples automatically by virtue of movement of the drive rod 32 towards the sider unit 25 whilst when the linear actuator 30 is removed from the mounting 28 this couplng automatically decouples. In order to achieve this automatic coupling, a coupling portion Is provided on the front side of the drive rod 32 which has at least one, and preferably two, claw elements 41,42 pivottally mounted on respective axes 44 which, in the coupled state, engage in a form-locking manner around a coupling portion 43 constructed in the manner of a flange at the end of the push rod 27 of the slider uni 25. This flange like coupling portion 43 is advantageously of rectangular construction in cross-section and furthermore provided with oblique guide surfaces 43" starting from Its front surface. As shown in Fig. 2, the claw elements 41,42 are arranged approximately paralel to one another on the front end of the drive rod 32 and constitute pincers. Associated wih the rear of the claw elements 41, 42 is a spring element 45 which produces a torque on the claw elements such that they are pressed inwardly at the front but only until they reach a position approximately parallel to one another. The spring element 45 is preferably composed of a pluraliy of plate springs or the Wee which are held by the drive rod 32. Fig. 3 elucidates the lateral sliding in of the linear drive 30", which is shown in chain lines, into Ithe mounting 28 secured to the siding gate valve 20. The fnear actuator 30 is provided at the front end of its cylinder 33 with a guide element 36, which extends transversely to the latter and which projects externally of this cylinder 33 around if. When the cyfnder 33 is pushed in the direction of the illustrated arrow 31 , this guide element 36 is slid into a conical opening 29 in the mounting 28 and then further into a guide groove 38 in the mounting 28, which is U-shaped in cross-section. The guide groove 38 is so dimensioned that the guide element 36 is retained in it in an approximately form-locking manner. The conical shape of the opening 29 enables the cylinder 33 to be slid comfortably into mounting 28, particularly if this cylinder is actuated by a manipulator, which is not shown in detal. Furthermore, a travel limiting peg 56 is provided which passes through the push rod 27 in an elongate hole and is removably secured in the mounting 28. This travel limiting peg 56 limits the travel of the slider unit 25 as regards the closed posiion of the sliding gate valve. When couping the two coupling portions, the drive rod 32 is moved, as shown in Fig. 4 and Fig. 5, by the linear actuator 30 towards the push rod 27 of the slider unit 25 until it reaches the llustrated end position, which corresponds to the closed position of the sliding gate valve 20. As the drive rod 32 is advanced further, the claw elements 41,42 are spread outwardly along the guide surfaces 43" of the coupling portion 43 into the illustrated position until they snap inwardly as a result of the spring force of the spring element 45 and engage around the couping portion 43 in a form-locking manner. In this snapped-in state, contact surfaces 27" and 42,43", which contact one another for the purpose of a nearly play-free connection in the coupled state, are provided on the coupling portion 43 and on the inner surface of the associated claw element 41,42, respectively. The contact surface 42 of the claw element 41,42 is advantageously convexity cambered for the purpose of satisfactory snapping in of the claw element, as is shown clearly in fig. 5. These contact surfaces 27" and 42*,43" could advantageously also be arranged at a few degrees more than 90° to the direction of movement so that the claw elements would engage behind the flange projection on the coupling portion 43 in order to prevent undesired decoupling. After the couping process, the drive rod 32 is retracted in a travel range during operation. A further advantage in accordance with the invention is produced as a result of the construction of the mounting 28 on Ms Inner surface 28"28" corresponding to the claw elements 41,42. The inner surface 28* of the mounting is offset outwardly in the region of the illustrated coupled position with respect to the inner surface 28" in the region of the operating position of the coupling 40. This results in locking of the claw elements 41,42 by the inner surface 28" in the travel range during operation, as is shown clearly in Fig. 1. The inner surfaces 28" are thus arranged parallel to the direction of movement at a small spacing from the outer surfaces of the claw elements 41,42 and the latter are thus secured against unlocking. In the automatic decouping in accordance win the invention of the couping 40, the linear actuator 30 can be pulled out transversely to the direction of movement In the coupled position without any additional manipulation and in any desired travel poslion of the drive rod 32. The claw elements 41,42 are arranged for this purpose on the drive rod 32 with pivotal axes 44 which extend parallel to one another and in the same direction as the wihdrawal direction of the linear actuator. During withdrawal of the linear actuator 30 the two claw elements 41/42 slide in the snapped-in state transversely to the longitudinal direction of the push rod 27 on the coupling portion 43 until they are released laterally of this coupling portion. Figs. 6 and 7 show another modification of a coupling 60 in accordance with the invention which, in the illustrated coupled state, connects the push rod 27 of the slider unit 25 to the drive rod 32 of the linear actuator 30. A mounting 50, which Is secured to the housing upper portion of the sliding gate valve, which is not shown in detail, is again provided, which mounting serves to receive and retain the linear actuator 30. For this purpose a transverse guide groove 38 Is provided in the end surface of this mounting 50 and a guide element 36, which may be slid into it in an approximately form-locking manner, is provided on the linear actuator 30. The couping 60 has a couping portion, which is arranged on the push rod 27, and a coupling portion cooperating with it on the front end of the drive rod 32. The coupling portion on the drive rod 32 is constituted by a couping sleeve 61 secured to the latter which intemaly has an opening 61" of rectangular cross-section which, as shown in Fig. 7, is laterally open. Furthermore, transverse grooves 62 are formed internally in this sleeve 61. A peg 69, which engages in an elongate groove in the mounting 50, is also provided laterally on this sleeve 61. The coupling portion on the push rod 27 has a central peg 37, which fits into this opening 61", and two pawls 63 on it which are mounted so as to be prvotable approximately radially on a respective axis 36 and which are pressed by a respective bending spring 64, mounted on the peg 37, into a starting position - as illustrated. In the coupled state, these pawls 63 are coupled in a respective one of the transverse grooves 62 in the sleeve 61 such that this sleeve 61 is held wth its forward, inwardly projecting annular portion 61", seen in the axial direction, between these pawls 63 and a rear abutment surface 27 on the push rod 27. in this coupled position, the push rod 27, and win it the slider unit 25, can be moved back and forth by the drive rod 32. The coupling and decoupling of the linear actuator 30 to and from the housing upper portion 56 is realsed in the manner in accordance with the invention in this coupling 60 also. When couplng, the linear actuator 30 is firstly slid in the same manner as shown in Fig. 3 into the guide groove 38 in the mounting 50. Thereafter, the linear actuator 30 is actuated and the drive rod 32 thus extended until its sleeve 61 is pushed over the peg 37 and the pawls 63 are forced inwardly into a respective recess 37. As soon as the annular portion 61" of the sleeve comes Into contact with the abutment surface 27" on the push rod 27, the pawls 63 snap into the transverse groove 62 whereby the coupling has been produced wihout addiional manipulations. When decoupling, the linear actuator 30 can be withdrawn in any desired travel posiion of the push rod 27 transversely to the direction of movement of its drive rod 32. It can be seen in Fig. 7 that this sleeve 61 is released transverse to the axis of movement by the construction of its recess 62*, which is open on one side, and by the lateral opening 29 in the mounting. The invention has been adequately explained with the discussed exemplary embodiment. It may, however, be realised in a different construction. Thus only one tillable claw element and, opposed to it, one complementary abutment surface for entering the two coupling portions could me provided. This daw element could in principle also engage in an elongate recessed groove at the end of the push rod 27. In principle, the couplng portion wih the claw elements could be equally well provided on the push rod of the sider uni and the corresponding coupling portion with the flange-like construction provided on the drive rod of the linear actuator. WE CLAIM: 1. Sliding gate valve for a vessel containing molten metal comprising a slider unit (25), which is longitudinally guided in a slider housing (21,22) and has a push rod (27) and which may be connected via a coupling (40,60) to a drive rod (32) of a linear actuator (30), a mounting (28) for receiving the linear actuator (30) being provided on the slider housing (21,22),characterized in that, the coupling (40,60) is so constructed that when the linear actuator (30) is slid into the mounting (28) it automatically couples as a result of movement of the drive rod (32) towards the slider unit (25), whereby the coupling (40) has a coupling portion (43) on the end of push rod (27) of the slider unit (25) and a coupling portion on the front end of the drive rod (32) of the linear actuator (30), which are coupling with the movement of the drive rod (32), whereas this coupling (40,60) automatically decouples when the linear actuator (30) is removed from the mounting (28). 2. Sliding gate valve as claimed in claim 1, wherein the coupling (40) has a coupling portion (43) on the end of the push rod (27) of the slider unit (25) and a coupling portion on the front end of the drive rod (32) of the linear actuator (30), at least one., preferably two, pivotally mounted claw elements (41,42) being associated with the one coupling portion which, in the coupled state, engage around the other flange—like coupling portion (43) in a form—locking manner. 3. Sliding gate valve as claimed in claim 2, wherein the claw elements (41,42) which are pivotally mounted on the drive rod (32), are arranged approximately parallel to one another in the decoupled state and constitute pincers, the rear of these claw elements (41,42) being so acted on by a spring element (45) mounted on the drive rod (32) that their front portions are pressed inwardly. 4. Sliding gate valve as claimed in claim 2 or 3, wherein the flange—like portion (43) provided on the end of the push rod (27) of the slider unit (25) is of rectangular cross—section and has guide surfaces (43") on its end face, these claw elements (41,42) being spread outwardly along these guide surfaces (43") during the coupling process unit they snap in automatically at the coupling portion (43) and engage around it in a form—locking manner. 5. Sliding gate valve as claimed in one of claims 2 to 4, wherein the mounting (28) is arranged offset at the inner surface (28";28") corresponding to the claw elements (41,421 such that the claw elements are pivoted in the vicinity of the closed position of the sliding gate valve but are lacked against pivoting in the travel range during operation. 6. Sliding gate valve as claimed in claim 4, wherein the linear actuator (30) may be withdrawn for decoupling transverse to the direction of movement of the drive rod (32) in any desired travel position, the mutual contact surfaces (27",42",43") of the claw elements (41,42) situated in the snapped—in state and of the coupling portion (43) extending transversely to the direction of movement of the drive rod (32) so that, during the decoupling process, the claw elements slide on the flange—like coupling portion (43) until they are released from it. 7. Sliding gate valve as claimed in claim 6, wherein the mutual contact surfaces (27", 42", 43") of the claw elements (41,42) situated in the snapped—in state and of the coupling portion (43) extend at right—angles to the direction of movement of the drive rod (32) so that, during the decoupling process, the claw elements slide on the flange—like coupling portion (43) until they are released from it. 8. Sliding gate valve as claimed in claim 1, wherein the coupling (60) has a coupling portion, which is provided on the end of the push rod (27) and which has a central peg (37) with a respective projecting pawl (63) on both sides, and has a coupling portion, constituting a sleeve (61), on the front end of the drive rod (32) of the linear actuator (30), whereby the peg (37) is slid in the coupled state into the sleeve (61) and its pawls (63) engage in a form—locking manner in transverse grooves (62) in the sleeve (61), whereby the sleeve is coupled with its front annular portion (61") between these pawls and an abutment surface (27*) on the push rod (27). 9. Sliding gate valve as claimed in claim 8, wherein the linear actuator (30) may be retracted transverse to the direction of movement of the drive rod (32) for the purpose of decoupling, the sleeve (61) having an opening (62"), which is open on one side, for this purpose, by means of which this sleeve (61) is released from the peg (37) and from the pawls (63) engaging in its transverse grooves (62). A sliding gate valve for a vessel containing molten metal has a push rod (27), which is associated with a slider unit longitudinally guided in a slider housing, which slider unit may be connected by means of a coupling (40) with a drive rod (32) of a linear actuator (30), a mounting (28) for receiving the linear actuator (30) being provided on the slider housing. The coupling (40) is so constructed that it automatically couples, when the linear actuator (30) is slid into the mounting (28), by virtue of movement of the drive rod (32) towards the slider unit (25) and this coupling (40) automatically decouples when the linear actuator (30) is removed from the mounting (28) transversely to the direction of movement of the drive rod (32). The one coupling portion of the coupling (40) has claw elements (41,42) which are spread outwardly during the coupling process along guide surfaces (43") on the other coupling portion (43) until they automatically snap in at it and engage around it in a form-locking manner.

Documents:

00668-cal-1998-abstract.pdf

00668-cal-1998-claims.pdf

00668-cal-1998-correspondence.pdf

00668-cal-1998-description (complete).pdf

00668-cal-1998-drawings.pdf

00668-cal-1998-form 1.pdf

00668-cal-1998-form 2.pdf

00668-cal-1998-form 3.pdf

00668-cal-1998-letter patent.pdf

00668-cal-1998-pa.pdf

668-CAL-1998-(07-02-2012)-FORM-27.pdf

668-CAL-1998-FORM 27.pdf