Sliding closure for a vessel containing molten metal

A sliding closure for a vessel containing molten metal, having a slider unit guided in a slider housing, the slider unit having a push rod that can be connected to a drive rod of a linear drive via a coupling, wherein a mounting element for the linear drive is provided on the slider housing and receives the push rod and the drive rod on a coupling side. The mounting element is equipped with an automatically operating locking device for the linear drive. The slide closure operates reliably, both during the casting process and during transport thereof between the various stations of the plant.

FIELD OF THE INVENTION

The invention relates to a sliding closure for a vessel containing molten metal, having a slider unit guided in a slider housing, said slider unit having a push rod that can be connected to the drive rod of a linear drive via a coupling, wherein a mounting element for the linear drive is provided on the slider housing, said element receiving the push rod and the drive rod on the coupling side.

BACKGROUND OF THE INVENTION

Slide closures of this type are used, for example, for the continuous casting of steel in order during the casting process to steer the molten flow flowing out of the vessel and, if necessary, to interrupt it. Here it is known that the vessel must periodically be moved to and fro between the casting platform and the plant supplying the molten mass. In order to accelerate the operational procedures linear drives are provided in both stations. Here the latter are respectively pushed into the mounting element of the sliding closure where their drive rod is then coupled to the push rod of the slider unit. In European patent specification EP 0 875 320 a coupling provided for this purpose is described which facilitates the fitting and removal of the linear drive and simplifies the coupling processes.

However, with the known sliding closures of this type there is a risk that during operation, due to the rough method of operation or incorrect handling, the linear drive comes away from its mounting element and so causes severe disruption to the casting operation.

A similar thing can occur with the periodic transport of the vessel between the different stations of the plant. That is to say, there is then a risk that the sliding closure opens unintentionally if it is handled incorrectly during transport. In both cases the consequences are serious, both from a commercial point of view and with regard to the safety of the people employed here.

OBJECTS AND SUMMARY OF THE INVENTION

The object which forms the basis of the invention is to avoid these disadvantages and to provide a sliding closure of the type specified at the start which guarantees a high degree of operational reliability even with the rough operation which is normal at casting plants.

This object is achieved according to the invention in that the mounting element is equipped with a locking device for the linear drive and/or a locking device for the push rod of the slider unit.

In this way, on the one hand it is ensured that the linear drive is held correctly in the mounting element after said linear drive has been drawn into the latter until the sliding closure leaves the one station in order to change over to the other station. On the other hand, it is also ensured that the sliding closure does not open unintentionally during transport from one station to the other.

Furthermore, the invention makes provision such that the locking device for the linear drive has a locking rod attached to it parallel to the axis on the drive rod and which cooperates with a spring-loaded locking catch attached to the mounting element. In the fitted state the latter encompasses the locking rod sliding therein over the whole stroke length of the drive and so causes the latter to sit securely in the mounting element for as long as it is fitted in the latter.

It is advantageous within the context of a simple design for the locking rod to be attached to a flange of the drive rod in the region of its coupling part.

According to the invention the locking rod has on the coupling side a recess which when the drive rod is drawn in can engage with the locking catch and afterwards can be released again from the locking catch. The locking and unlocking of the linear drive takes place automatically when the latter is drawn in and out with the drive rod drawn in.

Advantageously the locking rod has on its end facing away from the coupling a further recess which can be released from the locking catch when the drive rod is drawn out. Here the unlocking of the linear drive also takes place automatically when the latter is drawn out with the drive rod drawn out.

The invention also makes provision such that the locking catch is mounted laterally to the locking rod in a bolt guided within the mounting element, it advantageously being able to be spread open by turning or moving the bolt. Therefore, by operating the bolt the locking of the linear drive can be released at any time as required.

Furthermore, according to the invention provision is made such that the locking device has for the push rod of the slider unit a spring-loaded lever pivotably mounted in the mounting element which is provided with a detent disposed close to the pivot axis and a blocking pin disposed on the lever end facing away from the pivot axis, the detent and the blocking pin projecting into the mounting element and cooperating here with the coupling part of the drive rod or with a stop surface of the push rod. When the linear drive is drawn out of the mounting element the detent, and so the blocking pin, are automatically pivoted inwards by means of which the push rod is locked with the blocking pin. In this way one prevents the sliding closure from opening unintentionally during subsequent transport within the plant.

Alternatively, the locking device for the push rod can have two detents projecting into the mounting element and which are connected to one another by means of a connecting rod rotatably mounted in the mounting element, and which cooperate with stop surfaces of the linear drive and of the push rod which are advantageously formed by a stroke limitation bolt disposed laterally to the latter in the push rod and by a supporting plate of the linear drive that can be pushed into the mounting element. Upon drawing the linear drive into the mounting element the two detents are pivoted outwards and the push rod can move freely within the mounting element. If the linear drive is drawn out, both detents then pivot inwards again to such an extent that the push rod is locked by the detent cooperating with its stop surface.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1shows a sliding closure1on a vessel containing molten metal which is shown in the figure partially as a ladle2. The ladle2has an outer steel coating3, a fire-resistant lining4and an outlet5which is formed by a fire-resistant perforated brick6and a fire-resistant casing7. Disposed on the outlet5is the sliding closure1comprising a housing upper part8with a fire-resistant base plate9inserted in the latter, a housing frame10and a slider unit11braced releaseably within the latter, having a fire-resistant slider plate12and a discharge casing13adjacent to the latter. By moving the slider unit11and the slider plate12inserted within the latter longitudinally, the outlet5can be brought from the opening position illustrated into a restricting or closure position.

In order to move the slider unit11to and fro the latter can be connected via a push rod14and a coupling15to the drive rod16of a linear drive17in the form of a hydraulic cylinder/piston unit. The linear drive17is generally fitted onto the ladle2filled with molten metal and equipped with the closed sliding closure1when said ladle is brought onto the casting platform. After emptying the ladle the linear drive17is taken away from the ladle again. Next the ladle is transported by a crane away from the casting platform to a ladle location. Here the process described is repeated with a drive positioned at the ladle location.

On the slider housing8,10a mounting element18receiving the push rod14and the drive rod16on the coupling side is provided for the linear drive17. The coupling15located here is in the form of a catch coupling. As can be seen fromFIG. 2it comprises a flange-type coupling part19on the push rod14and a coupling part20formed by two catch elements on the drive rod16, in the coupled state the catch elements encompassing the coupling part19with a form fit. The linear drive17is pushed into the mounting element18on the side. Then the coupling is produced automatically by moving the drive rod16towards the slider unit11. Uncoupling likewise takes place automatically when one pulls the linear drive17out of the mounting element18.

Disposed in the mounting element18there is a locking device21for the linear drive27which, as can be seen fromFIGS. 2 to 6, is composed of a locking rod22and a locking catch23cooperating with the latter. The locking rod22is attached to a flange24of the drive rod16in the region of its coupling part20. It is aligned axially parallel to the drive rod16.

The locking catch23is mounted laterally to the locking rod22in a bolt25which is guided within the mounting element18. Its two catch elements are thus held by the bolt25. By taking away the bolt25, if so required the catch elements can be released from the mounting element, by means of which the locking of the linear drive is cancelled.

The locking rod22has two recesses in the form of annular grooves26,27which correspond to the stroke end positions of the drive rod16. The diameter of the annular groove26has dimensions such that upon inserting the linear drive17in the mounting element18with a drawn in drive rod the annular groove26can engage with the locking catch23, whereas when the linear drive17is drawn out it can be released from the locking catch23.

When moving the drive rod16the locking rod22is also moved, the locking catch23encompassing the latter in the region between the annular grooves26,27so strongly that it is then impossible to release the locking rod22from the locking catch23laterally to its longitudinal axis. Therefore, during its whole working stroke the linear drive17remains securely locked, and so automatically acting locking and unlocking is produced which takes place without any manual operation.

The diameter of the annular groove27has dimensions such that it can be released from the locking catch23when the linear drive17is drawn out of the mounting element18. It is therefore possible, if so required, to remove the linear drive, even when the drive rod16is drawn out. Furthermore, the locking rod22serves to prevent the drive rod16from rotating.

The sliding closure according toFIGS. 7 to 13is equipped with a locking device28for the push rod14. It comprises a lever29mounted pivotably in the mounting element18with a tappet31close to the pivot axis30and a blocking pin32on the lever end facing away from the pivot axis, the tappet31and the blocking pin32projecting into the mounting element18and cooperating here with the coupling part20of the drive rod16and with a stop surface33of the push rod14. A stroke limitation bolt34with a handle35pushed into the push rod14laterally to the longitudinal axis forms the stop surface33.

The pivot axis30of the lever29sits in a bearing block36which is attached to the mounting element18. The lever29is acted upon by a spring37with an adjustment screw38in the inwardly pivoting direction.

FIG. 9shows the locking device28with the lever29pivoted in. In the position shown the drive rod16is drawn in, whereas the push rod14adopts its end position with the slider closed. In order to couple the drive rod16onto the push rod the former is drawn out within the mounting element18until the coupling is produced between the two. It thus actuates the tappet31, by means of which the lever29is pivoted out, and the latter takes the blocking pin32out of the trajectory of the stroke limitation bolt34. The push rod14can therefore move freely within its working stroke for as long as the drive rod16and the push rod14are coupled.

If, however, the coupling is released again and the drive rod16drawn back, the tappet31can then pivot back into its initial position, by means of which the spring-loaded lever29pivots back and the blocking pin32projects once again into the trajectory of the stroke limitation bolt34. In this way it is ensured that after the linear drive17has been dismantled, the sliding closure does not open unintentionally because then the push rod14is locked by the blocking pin32. With this locking device28automatically acting locking and unlocking has in turn been produced.

With the sliding closure according toFIGS. 14 to 20the locking device28for the push rod14has two detents47,48projecting into the mounting element18which are connected to one another by a connecting rod39rotatably mounted in bearing blocks43, and cooperate with stop surfaces41of the push rod14and of the linear drive16. This stop surface41of the linear drive17is provided in a supporting plate42of the linear drive that can be pushed into the mounting element18, whereas the stop surface of the push rod14is located on an elevation of the latter.

The locking device28according toFIGS. 14 to 20, which also acts automatically, functions in the same way as the locking device according toFIGS. 7 to 13.

Before inserting the linear drive17into the mounting element18the detents47,48are pivoted into this mounting element18. Upon drawing the linear drive into the mounting element the supporting plate42strikes the detent48with the stop surface41and pushes it out to such an extent that the detent47connected to it via the connecting rod39pivots out of the trajectory of the push rod14. Therefore, the push rod14can move freely for as long as the linear drive17is inserted in the mounting element18.

If the linear drive is drawn out of the mounting element18, both detents47,48can then pivot back with the result that the detent47then projects into the trajectory of the stroke limitation bolt34again. It is thus achieved that after the linear drive has been removed, the sliding closure does not open unintentionally during transport because the push rod14is then locked by the detent47in cooperation with the stop on the push rod.

As can be seen from the figures, the sliding closure according toFIGS. 2 to 6is only equipped with one cylinder lock in the form of the locking device21for the linear drive17. With the sliding closures according toFIGS. 7 to 17and14to20, instead of this the cylinder lock is combined with a transport lock in the form of the locking device28for the push rod14. It is therefore possible within the framework of the invention to incorporate both locking devices individually or together into the locking closure, particularly as in the latter case their functions obviously complement one another.

Due to the design proposed for the latter, it is also possible, without a great deal of complexity, to incorporate the locking devices subsequently into existing sliding closures.