EP0920935B1 - Support structure for an oscillating mould - Google Patents

Abstract

The links (3) are joined to the supports (1) and the mold carrier frame (2) using leaf spring hinges (20).

Description

The invention relates to a support frame for an oscillating mold with fixed vertical supports, on which support frames for Recording the mold are arranged with one another in pairs arranged handlebars, on the one hand with the straps and on the other hand are articulated to the support frame.

• Federgeführte Oszillation mit vier Exzenterantrieben: Die oszillierende Kokille ist in einem feststehenden Rahmen mittels vier Blattfedern aufgehängt und damit spielfrei geführt. Die Kokille ist wartungsfrei und spielfrei in vertikaler Richtung geführt. Nachteilig ist die Kokille nur auf ihrer Bahn in vertikaler Richtung geführt. Die Führung bezüglich ihrer Lage muß durch den Oszillationsantrieb an allen vier Ecken der Kokille sichergestellt werden. Hierzu sind bspw. zwei Exzenterwellen mit jeweils zwei Exzentern erforderlich.
• Kurzhebeloszillation mit zwei Exzentern: Die Kokille ist mit zwei Parallellenkern in senkrechter Richtung geführt. Der Antrieb erfolgt über einen Hebel, der die untere Kurbelschwinge über den Festlagerpunkt hinaus verlängert. Die Kokille ist auf ihrer senkrechten Auf- und Abwärtsbewegung sowohl in der Bahn als auch in der Lage geführt. Nachteilig ist, daß das Fundament die doppelte Last der Kokille tragen muß. Die Lager müssen sowohl die Führungskräfte als auch die Hubkräfte tragen. Das ergibt einen vergleichsweise großen Aufwand an Wartungs- und Reparaturarbeiten.
• Parallellenker-Oszillation mit zwei hydraulischen Zylindern: Die Kokille ist mit zwei Parallellenkern in senkrechter Richtung geführt. Die Einleitung der Hubkraft erfolgt direkt unter der Kokille. Die Kokille ist auf ihrer senkrechten Auf- und Abwärtsbewegung sowohl in der Bahn als auch in der Lage geführt. Der Antrieb kann somit durch nur zwei Zylinder verwirklicht werden. Nachteilig ist, daß die Drehbewegung in den Lagern nur wenige Winkelgrade beträgt. Dafür müssen acht aufwendige Lagerungen gefertigt und im Betrieb gewartet werden. Die Lager müssen gegen Kühlwasser geschützt und durch ein Zentralfettschmiersystem geschmiert werden. Das Lagerspiel kann nicht durch Balancierung ausgeglichen werden.
• Resonanzkokille: Die Kokille ist je Seite mit zwei Blattfedern in einem Rahmen geführt. Die Blattfedern tragen die Kokille durch ihre Federkraft. Die Kokille hat eine spielfreie Aufhängung und braucht keine wartungsintensiven Lagerungen. Die Führung der Kokille in Bahn und Lage ist einwandfrei. Nachteilig ist, daß die Federn großen Einfluß auf die Schwingungsform haben, weil die Federkonstanten sehr groß sein müssen, um die Kokille zu tragen. Im einfachsten Fall kann eine sinusförmige Schwingungsform mit der Frequenz der Eigenresonanz des Feder/Masse-Systems durchgeführt werden. Eine definierte Führung der Kokille ist nur mit einer sehr steifen Blattfeder möglich. Bei Schwingungsfrequenzänderung kann es zu großen u. U. nicht beherrschbaren Reaktionskräften, die das System überbeanspruchen, kommen.
• Federgeführte Oszillation mit Hydraulikantrieb: Die oszillierende Kokille ist auf einen Kokillenrahmen gesetzt. Dieser Rahmen ist je Seite mit zwei Blattfedern geführt, ähnlich der zuvor beschriebenen Resonanzkokille. Die Blattfedern haben eine geringe Federkonstante, und es fehlt die Steifigkeit. Deshalb muß die Kokille in der Lage zwangsgeführt werden. Es befinden sich vier Hydraulikzylinder als Antrieb unmittelbar unterhalb der Kokille. Die Kokille ist wartungsfrei und spielfrei in vertikaler Richtung geführt. Durch den hydraulischen Antrieb können unterschiedliche Hubformen gefahren werden. Nachteilig ist, daß die Kokille nur auf ihrer Bahn in vertikaler Richtung geführt ist. Die Führung bezüglich ihrer Lage muß durch den Oszillationsantrieb an allen vier Ecken der Kokille sichergestellt werden. Das wird mit den vier Hydraulikzylindern sichergestellt. Dabei muß die Hydrauliksteuerung so ausgebildet sein, daß alle vier Zylinder absolut synchron laufen. Der hierzu erforderliche mechanische-technologische Aufwand ist vergleichsweise groß.

In continuous casting plants, the mold with its oscillation must be given special attention. The leadership in the upward and downward movement largely decides on the number of very costly breakthroughs in operation. The following oscillation designs have been implemented so far:

• Spring-guided oscillation with four eccentric drives: The oscillating mold is suspended in a fixed frame by means of four leaf springs and is therefore guided without play. The mold is maintenance-free and has no play in the vertical direction. The disadvantage is that the mold is only guided on its path in the vertical direction. The positional position must be ensured by the oscillation drive at all four corners of the mold. Two eccentric shafts, each with two eccentrics, are required for this.
• Short lever oscillation with two eccentrics: The mold is guided in a vertical direction with two parallel bars. It is driven by a lever that extends the lower crank arm beyond the fixed bearing point. The mold is guided in its upward and downward movement both in the path and in the position. The disadvantage is that the foundation has to bear twice the load of the mold. The bearings must carry both the managers and the lifting forces. This results in a comparatively large amount of maintenance and repair work.
• Parallel link oscillation with two hydraulic cylinders: The mold is guided in a vertical direction with two parallel links. The lifting force is introduced directly under the mold. The mold is guided in its upward and downward movement both in the path and in the position. The drive can thus be realized by only two cylinders. The disadvantage is that the rotational movement in the bearings is only a few degrees. To do this, eight elaborate bearings have to be manufactured and maintained in operation. The bearings must be protected against cooling water and lubricated using a central grease lubrication system. The camp game cannot be compensated by balancing.
• Resonance mold: The mold is guided in a frame with two leaf springs on each side. The leaf springs support the mold by their spring force. The mold has a play-free suspension and does not require maintenance-intensive storage. The guidance of the mold in the path and location is flawless. It is disadvantageous that the springs have a great influence on the shape of the vibration, because the spring constants have to be very large in order to carry the mold. In the simplest case, a sinusoidal waveform can be carried out with the frequency of the natural resonance of the spring / mass system. Defined guidance of the mold is only possible with a very stiff leaf spring. When the vibration frequency changes, it can be too large. U. uncontrollable reaction forces that overuse the system come.
• Spring-guided oscillation with hydraulic drive: The oscillating mold is placed on a mold frame. This frame is guided with two leaf springs on each side, similar to the resonance mold described above. The leaf springs have a low spring constant and lack rigidity. The mold must therefore be positively guided. There are four hydraulic cylinders as drives directly below the mold. The mold is maintenance-free and has no play in the vertical direction. The hydraulic drive enables different stroke shapes to be used. The disadvantage is that the mold is only guided on its path in the vertical direction. The positional position must be ensured by the oscillation drive at all four corners of the mold. This is ensured with the four hydraulic cylinders. The hydraulic control must be designed so that all four cylinders run absolutely synchronously. The mechanical-technological effort required for this is comparatively large.

EP 0 421 560 A1 describes an oscillation device for Continuous casting molds with a square base frame, on which two rotating drives Eccentric shafts are arranged in parallel. About the on it arranged eccentric, the oscillation can be transferred to the mold.

In order to have to move small masses with exact movement synchronization, it is proposed that the mold in an opening of a support plate is attached that at each corner below the support plate a wear plate is arranged, and that this wear plate on an eccentric outer ring that rotates on the eccentrics is stored. In addition, spring bars are parallel to the edges provided the support plate. The effort for the bearing arrangements is comparatively high in terms of maintenance and wear.

EP 0 150 357 describes a guide device for an oscillating driven continuous casting mold, being on a mold lifting table Brackets are attached, each with a spring element are connected to a frame. On one in its middle area on the frame anchored spring support is a leaf spring with Distance to this arranged and fixed with its ends on this. The mold lift table is over one on the middle of the leaf spring attached intermediate piece connected to the leaf spring.

DE-OS 22 48 066 discloses a further device for guiding an oscillating continuous casting mold. In this device is the mold attached to spring elements, which are transverse to the direction of oscillation are anchored to the supporting structure. These spring elements are clamped on one side in the manner of a cantilever, the Mold is attached to the free end. The spring elements are as multilayer spring assemblies designed in such a way that the deflection corresponding to the mold weight is at least that Oscillation stroke corresponds to the mold.

The present invention is based on the aforementioned prior art based on the task of a new solution for the suspension of the Specify mold, which in particular a freedom of play of the Joint points guaranteed even after a long period of operation thus freedom from maintenance and freedom from wear of the joints enables and with extremely inexpensive manufacture of the mold suspension none pronounced with regard to the spring / mass system Has natural resonance and extremely precise guidance of the oscillating Mass allows.

To solve the problem with a supporting structure for an oscillating Chill mold of the type mentioned in the preamble of claim 1 the invention proposed that the handlebars with the carriers and Support frame are connected by means of movable hinges, the Hinges are designed as leaf spring hinges.

• Wartungsfreiheit der Gelenke.
• Verschleißfreiheit der Gelenke.
• Äußerst preiswerte Fertigung der Blattfederverbindungen.
• Zum Antrieb genügen zwei Hydraulikzylinder, d.h. es ist keine Hydraulik erforderlich, welche vier Zylinder synchronisieren muß.
• Das Fundament muß keine doppelte Last durch ungünstige Hebelverhältnisse aufnehmen.
• Die Federn haben nicht die Aufgabe, die Kokille zu balancieren und haben daher keinen Einfluß auf die Oszillationsfrequenz oder deren Verlauf. Das Feder/Masse-System besitzt keine ausgeprägte Eigenresonanz.

The construction of the supporting structure according to the invention enables the following positive properties with great advantage:

• Maintenance-free of the joints.
• No wear on the joints.
• Extremely inexpensive manufacture of leaf spring connections.
• Two hydraulic cylinders are sufficient for the drive, ie no hydraulic system is required which has to synchronize four cylinders.
• The foundation does not have to bear a double load due to unfavorable leverage.
• The springs do not have the task of balancing the mold and therefore have no influence on the oscillation frequency or its course. The spring / mass system has no pronounced natural resonance.

Further advantages are in accordance with the features of the subclaims intended.

Figur 1

ein Traggerüst für eine oszillierende Kokille, in perspektivischer Ansicht;

Figur 2

eine Kokille im Aufbau auf einem Traggerüst in perspektivischer Ansicht.

Details, features and advantages of the invention result from the following explanation of an exemplary embodiment schematically illustrated in the drawings. Show it:

Figure 1

a support frame for an oscillating mold, in perspective view;

Figure 2

a mold under construction on a supporting structure in a perspective view.

1 shows a supporting structure for an oscillating mold 10 (FIG. 2) with two fixed vertical supports 1, each of which a support frame 2 is arranged with one another in pairs horizontal handlebars 3, the one hand with the carriers 1 and on the other hand are articulated to the support frame 2. The support frames are with vertical supports 5 and with cantilever arms 4 trained to accommodate the mold 10. Between each carrier 1 and the vertical support 5 parallel to it at a distance are these connecting horizontal handlebar 3 arranged with hinges.

The hinges are designed as leaf spring hinges 20. This Leaf spring hinges are, as previously pointed out, maintenance-free and extremely wear-free in their joints inexpensive to manufacture leaf spring connections. The drive can for each of the two support frame 2 by a hydraulic cylinder 11 occur, i.e. it is not a hydraulic system with complex synchronization devices required. The foundation must be extremely favorable leverage does not take up a double load. The The spring / mass system also has no natural resonance. As a result, it is provided that only 4 below each cantilever a drive member 11 the oscillating drive of the support frame 2nd effected with the mold 10.

A particularly precise guidance with regard to the mold position also comparatively soft feathers is achieved by using a rigid Intermediate piece, the beam 12, in the horizontal handlebar 3 allows. This bar 12 is horizontal at one end Leaf spring hinge 20, 20 'on the carrier 1 and on the opposite End with a similar leaf spring hinge 20, 20 'with the vertical support 5 articulated.

Each leaf spring hinge 20, 20 'is about a horizontal one Swing axis x-x designed and arranged to be swingable.

The cross section of a leaf spring hinge 20, 20 'should advantageously be designed so that its moment of inertia in the direction of deformation is small and large in the direction of leadership. That is, the Tensions created by the movement are smaller than that permissible stresses for alternating bending stress. In the direction of leadership May the deformation due to that caused by the executives arising voltage, however, only be very small.

A particularly inexpensive manufacture of leaf spring connections results from the free ends of each leaf spring hinge 20, 20 'by means of screw connections 13 Clamped connections clamped in horizontal slots 14, 14 ' are held.

A particularly favorable attachment for the leaf spring hinges 20, 20 'results from the fact that both on the carrier 1 and on the vertical Support 5 mutually projecting claws 15, 15 'for screwing on the leaf spring hinges 20, 20' are present.

Fig. 2 shows a complete support structure for an oscillating Mold 10, wherein the same elements with the same reference numerals are provided. 2 is the constructive one Straightforwardness and practicality of the supporting structure according to the invention for an oscillating mold 10 clearly for the person skilled in the art recognizable.

LIST OF REFERENCE NUMBERS

1

Vertical beam

2

supporting frame

3

horizontal handlebar

4

cantilever

5

vertical support

10

mold

11

drive member

12

bar

13

screw

14

slot

15

paw

20

Leaf spring hinge

Claims (7)

1. A support structure for an oscillating mould (10), with stationary vertical posts (1), on which support frames (2) for accommodating the mould (10) are arranged, and with connecting rods (3) that are arranged underneath one another in pairs and connected in an articulated fashion to the posts (1) on one side and to the support frames (2) on the other side,
   characterized by the fact
   that the connecting rods (3) are connected to the posts (1) and to the support frames (2) by means of movable hinges, wherein the hinges are realized in the form of leaf spring hinges (20).
2. The support structure according to Claim 1,
   characterized by the fact
   that the support frame (2) forms a jib boom (4), and by the fact that a drive element (11) for realizing the oscillating movement of the support frame (2) and the mould (10) is arranged underneath each jib boom (4).
3. The support structure according to Claim 1 or 2,
   characterized by the fact
   that each connecting rod (3, 3') contains a rigid intermediate piece, for example, a rigid beam (12), wherein a horizontal leaf spring hinge (20, 20') connects one end of the rigid intermediate piece to the post (1) in an articulated fashion, and wherein another leaf spring hinge (20, 20') connects the opposite end of the rigid intermediate piece to the support frame (2) in an articulated fashion.
4. The support structure according to at least one of Claims 1 - 3,
   characterized by the fact
   that each leaf spring hinge (20, 20') is realized and arranged such that it can be pivoted about a horizontal pivoting axis (x-x).
5. The support structure according to at least one of Claims 1 - 4,
   characterized by the fact
   that a leaf spring hinge (20, 20') consists of a multilayer spring assembly comprising comparatively thin individual leaf springs.
6. The support structure according to at least one of Claims 1 - 5,
   characterized by the fact
   that the free ends of each leaf spring hinge (20, 20') are clamped in horizontal sleds (14, 14') by means of screw connections (13).
7. The support structure according to at least one of Claims 1 - 6,
   characterized by the fact
   that brackets (15, 15') which project toward one another and serve for screwing on the leaf spring hinges (20, 20') are arranged on the post (1), as well as on the support frame (2).

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