EP1725348A1

EP1725348A1 - Drive spindle for the main drive of a roll stand

Info

Publication number: EP1725348A1
Application number: EP06724203A
Authority: EP
Inventors: Maik Berger; Achim Klein; Florian Lindner; Peter Rainer
Original assignee: SMS Demag AG
Current assignee: SMS Siemag AG
Priority date: 2005-04-12
Filing date: 2006-04-10
Publication date: 2006-11-29
Anticipated expiration: 2026-04-10
Also published as: BRPI0604834A; ATE383917T1; US20070251349A1; EP1725348B1; DE502006000297D1; CA2568837C; CA2568837A1; DE102005054742A1; JP2007538204A; RU2006139747A; RU2339472C2; ES2297824T3; JP4040670B2; WO2006108596A1; US7784380B2

Abstract

The invention concerns a drive spindle (1) for the main drive of a rolling stand, which has: a first shaft (3) for transmitting torque from a drive motor (2) to a coupling element, especially to a multiple spline profile, and a second shaft (5) for transmitting the torque from the coupling element, especially the multiple spline profile, via a swivel joint (4) to a roll (6) of the rolling stand, wherein the swivel joint (4) has a wobbler (7), which is rotationally rigidly connected with the roll (6), and a second spindle head (8), which is rotationally rigidly connected with the second shaft (5), and wherein the rotational connection between the wobbler (7) and the spindle head (8) is produced by sliding bearings and a journal (9), which is rotationally rigidly connected with the spindle head (8) but is supported in a way that allows an angle of inclination (α) between the axis of rotation (10) of the roll (6) and the axis of rotation (11) of the second shaft (5). In order to achieve improved transmission of axial forces by the swivel joint, the invention provides that a bearing element (12, 13) for absorbing forces in the direction of the axes of the second shaft (5) and the roll (6) is arranged between the wobbler (7) and the spindle head (8), such that a push rod (14) for transmitting axial forces between the wobbler (7) and the spindle head (8) is arranged between the two bearing elements (12, 13).

Description

Drive spindle for the main drive of a rolling stand

The invention relates to a drive spindle for the main drive of a roll stand, comprising: a first shaft for transmitting torque from a drive motor to a coupling element, in particular to a splined profile, and a second shaft for transmitting the torque from the coupling element, in particular the splined profile over a hinge to a roll of the roll stand, wherein the rotary joint comprises a roller hit, which is rotatably connected to the roller, and a second spindle head, which is rotatably connected to the second shaft, and wherein the rotational connection between roller hit and spindle head by sliding blocks and a Pin is made, which is rotatably connected to the spindle head, but a tilt angle between the axis of rotation of the roller and the axis of rotation of the second shaft is mounted to allow.

Drive spindles for the mainframe main drive of this type must often be designed as Axialverschiebesystem to accomplish a length compensation can. For this purpose, drive shafts are usually used with universal joints.

From DE 102 11 883 C1, such a solution is known, in which case the aim is to equip the universal joint of a propeller shaft for driving the roller of a rolling mill with a holding device which is adjustable to different fixed flexion angle of the propeller shaft. For this purpose, a special embodiment of the propeller shaft is proposed with attached to the fork arms of the spigot base parts together with retaining bolts.

Similarly, DE 29 26 710 C2 proposes a shaft assembly with universal joints for roller drive. To a propeller shaft without restriction the rotation diameter so that the flexion angle of each universal joint during standstill of the propeller shaft can be limited to an arbitrary value, it is proposed that one end of a bolt located in the universal joint is angularly movably received in a radially movable to the coupling axis element of a yoke, while the movable member is fixable in any position with a locking device.

From DE 32 31 752 C1 a connection hit with automatic clearance compensation for connecting a roll neck with a drive spindle for a rolling stand is known. There, wedge-shaped drivers for the roll neck are provided, which are arranged slidably on two pairwise cooperating, in the connection piece after the inside inclined towards the center and prism angle corresponding to the wedge angle of the driver prism surfaces. This is intended that the play compensation is effective on all sides of the roll neck and able to compensate automatically by wear or when replacing rolls resulting dimensional differences.

Another design of a joint shaft for driving a roll of a rolling mill is known from DE 197 45 199 C1. Again, universal joints are used to two shaft parts rotatably, but angularly connectable with each other. The same applies to the solution known from EP 1 393 826 A1.

Cardan shafts with universal joints are filigree and thus expensive. Furthermore, it is usually necessary that they have to be maintained in special workshops, which represents a high logistical effort.

Basically, instead of universal joints and flat-pin spindles in the drive spindle for roller drive in question. Such a solution is apparent from DE-OS 23 62 524. There is an axially displaceable, automatically engageable and disengageable joint coupling of the drive spindle for replaceable rolling described with which a quick engagement and disengagement of the clutch and a safe entrainment when moving the scaffold should be possible.

In this solution, however, it is problematic or impossible to transmit efficient axial forces on the flat-pin spindle, without burdening them over charge. In such a design, it would be necessary for the purpose of length compensation of the drive spindle to equip the motor-side spindle head with moving cylinders and to regulate them so that the roller axial displacement is tracked parallel. Only then would it be ensured that the roller-side spindle head can not slip off the roller. This not only represents an unacceptable expense; in the event of a malfunction, greater damage to the rolling mill would be expected.

The invention is therefore based on the object, a drive spindle for the main drive of a rolling stand of the type mentioned with a flat-pin spindle equip so that the disadvantages mentioned are prevented. It should also be in the execution of the function of length compensation of the drive spindle a robust, simple design and thus inexpensive and easy to maintain arrangement can be created. The aim is also that the hit with the roller can remain firmly connected.

The solution of this problem by the invention is characterized in that between the roller hit and the spindle head, which is arranged near the roller, a bearing element for receiving forces in the direction of the axes of the second shaft and the roller is arranged, wherein between the two bearing elements a plunger for transmitting axial forces between the roller hit and the spindle head is arranged.

According to the invention, therefore, a plunger is integrated into the rotary joint, which provides in cooperation with special bearing elements for the Axialkraftübertragung. As will be seen, an axial balancing force can thus be transmitted via the ram, whereby the articulated stones in the spindle head only have to transmit the drive torque and are not loaded by the axial force. The drive spindle can thus be charged the same, as would be the case without length compensation.

It is also advantageous that the hit can remain on the roller. An additional spindle head holder is not required.

In the case of a roll change, it is finally advantageously not necessary to actuate an additional blocking element, for. As a bolt, as provided in the prior art discussed above, occasionally.

A first development of the invention provides that the bearing elements are arranged concentrically to the respective axes of rotation of the roller and the second shaft.

The bearing elements preferably together with the plunger form a plain bearing point. In this case, the bearing elements in the contact region with the plunger may have a concave shape in section and the end regions of the plunger may have a convex shape corresponding to the concave shape. It is particularly advantageous if the bearing elements in the contact region with the plunger have, in section, essentially the shape of a hemisphere.

The pin may be substantially plate-shaped and have a recess for the passage of the plunger. The recess preferably has a conical shape, so that the plunger is movable in certain angular limits.

To facilitate a roll change, means may be provided with which the plunger is connected captive with the roller hit and / or with the spindle head. Advantageously, the plunger is pin-shaped, ie it then has a circular cross-section. The ratio of its length to its diameter is preferably between 4 and 10, preferably between 5.5 and 8.5. The radius of the hemisphere of bearing elements and plunger is preferably between half and twice the plunger diameter. In general, it applies here that the radii of the contact regions between the bearing elements and the plunger should be made sufficiently large in order to keep wear low. Although the relative movement increases substantially linearly with the radius, the surface pressure decreases quadratically with increasing radius. Therefore, the radius is preferably chosen large.

For a long service life and a good mode of operation it can be provided that in the contact region between at least one of the bearing elements and the plunger, a lubricant channel passing through the spindle head opens, via which lubricant can be supplied to the contact region. A particularly preferred embodiment of the invention provides that only in the contact region between one of the bearing elements and the plunger of the lubricant channel opens and that the plunger has a longitudinal bore passing through it for conveying lubricant in the region of the other bearing element.

The material selection of the components can be made so that good friction property arise. Advantageously, therefore, the bearing elements are made of a self-lubricating material, in particular of such having graphite.

For the known application of Balancierkräften can be arranged on or on the first shaft, a bearing body which is suitable for applying these Balancierkräfte on the second shaft. A training provides that the plunger consists of several interconnected components. In particular, the plunger may consist of a rod member, at the ends of each a plunger head is arranged. The components can be connected to each other with a screw. With multi-part design of the plunger has the advantage that only one head of the plunger can be replaced when worn. A design with a large plunger head may require demountability, because only then can the plunger with its slender central part be inserted through the passage bore in the journal.

For better dissipation of heat in particular from the contact point between the plunger and bearing elements ribs have proven to be preferred, which are preferably arranged in the region of at least one axial end of the plunger. The cooling of the spindle and turn the contact point between the plunger and bearing elements is further improved by the fact that the plunger has at least one bore for passing a cooling medium; It is advantageously arranged at least one bore in the axial end region of the plunger. By passing a cooling medium, such as water, so that efficient cooling can be achieved.

With the proposed invention, a possibility is created to make well-known flat-pin spindles particularly well suited for Walzenaxialverschiebesysteme in large rolling stands.

In the drawings, embodiments of the invention are shown. Show it:

1a shows two drive spindles for the main drive of two rolls of a roll stand in the side view,

1 b, the top view of the drive spindles according to FIG. 1 a, 2 is an enlarged view of the two drive spindles according to Fig. 1a,

3 shows the detail "X" of FIG. 2,

4 shows the section B-B of FIG. 1a,

5 is an enlarged view of the upper part of Fig. 3,

6 shows the detail "Z" of FIG. 2,

Fig. 7 shows an alternative embodiment of the invention in a representation of FIG. 5 and

Fig. 8 shows the plunger in perspective view.

In Fig. 1a and 1b, two drive spindles 1 for driving two rollers 6 can be seen in a rolling stand. It should be noted that the lower spindle is sketched in Figs. 1a, 2, 3 and 4 in a relative to the upper spindle rotated by 90 ° position to recognize the structure of the system easier. The drive spindles 1 are driven (right) by drive motors 2. The torque of the motors is transmitted to the rollers 6 (left). Both drive spindles 1 have two shafts 3 and 5. The roller 6 rotates about an axis of rotation 10, which is arranged horizontally. Meanwhile, the second axis of rotation 11 of the shafts 3 and 5 is present at a small tilt angle α to the horizontal, the z. B. between 2 ° and 12 °.

So that the torque can be transmitted despite the tilt angle α, a rotary joint 4 is arranged between the roller 6 and the second shaft. This is done in the manner of a flat pin joint. The rotary joint 4 consists of two elements, namely from the roller hit 7 and the spindle head 8, the torsionally stiff, but are pivotally connected to each other. At the roller hit 7 a pin (flat pin) 9 is formed, which extends into a corresponding recess in the spindle head 8 and is stored there.

The second shaft 5 is connected at its end facing away from the rotary joint 4 via a coupling element in the form of a splined profile (see Fig. 2) with the first shaft 3. Thus, an axial displacement between the shafts 3 and 5 and thus also the rollers 6 can be realized.

The detailed structure of the rotary joint 4 is apparent from Figures 3, 4 and 5.

The roller hit 7 and the spindle head 8 has in the region of the respective axis of rotation 10 and 11, a bearing element 12 and 13, which is block-shaped and inserted into the roller hit 7 or in the spindle head 8. At the side facing the respective other part, each bearing element 12, 13 has a dome-shaped concave recess, d. H. a hemispherical shape, as best seen in FIG. The radius R of the calotte is between half and twice the ram diameter D. As already mentioned above, the radius R is chosen to be large enough to keep wear low. The surface pressure between the bearing element 12, 13 and plunger 14 is thus kept low.

Between the two bearing elements 12, 13, a plunger 14 is arranged, which is suitable for transmitting axial forces from one spindle head to the other. This ensures that the pin 9 itself is not acted upon by axial forces; this only has the sliding blocks 9a and 9b, s. Figs. 3 and 4, hold. The plunger 14 is designed as a cylindrical pin and formed in its two end regions 15 and 16 corresponding to the dome shape of the bearing elements 12, 13.

In the pin 9, a conical recess 17 is provided, which is suitable for the axial passage of the plunger 14 (see Fig. 5). So that the plunger 14 does not fall apart at separate parts roller hit 7 and spindle head 8, it is arranged captive in the spindle head 8. For this purpose means 18 are provided. As can be seen from Fig. 5, these means 18 consist of a ring 22 which is fixed by means of a securing element 23 on the plunger 14. By a screwed-locking element 24 and by a projection 25 so that the axial freedom of movement of the plunger 14 is limited relative to the spindle head 8.

In order to ensure reliable operation of the system, it must be ensured that the sliding bearing bearing element ram is adequately supplied with lubricant. In the spindle head 8 for this purpose a lubricant channel 19 is arranged, the mouth of which lies on the dome surface of the bearing element 13 with the intersection of this surface with the axis of rotation 11. There, grease is supplied under pressure, so that the contact surface between the (right) end 16 of the plunger 14 with the bearing element 13 is well lubricated. So that the other storage location, d. H. the contact surface between the (left) end 15 of the plunger 14 is supplied with the bearing element 12 with lubricant, the plunger 14 is provided with a complete and centrally passing through longitudinal bore 20. Through this hole, grease can get from the right tappet end to the left.

The plunger 14 undergoes no rotation during operation of the spindle assembly, but it performs a tumbling motion about its longitudinal axis. The intended lubricant supply ensures good lubrication of the bearings. The friction situation in the bearing point can be favored by the fact that self-lubricating materials are used. When installing and removing the roller 6, the flat pin 9 of the roller impact 7 is pushed into the spindle head 8. The plunger 14 is - as explained - held captive in the spindle head 8. When retracting a new roller, the one (left) end of the plunger 14 centered in the dome of the bearing element 12th

As can be seen from Fig. 5, it is provided that one of the two pivot points is arranged at the hemispherical ends of the plunger 14 on the roll axis and the other on the spindle axis. Furthermore, it is provided that the radii R are kept small at the ends of the plunger 14 (the above explanations on the choice of radii is made, according to which on the other hand a sufficiently large radius R must be provided to a low surface pressure between the parts and thus a low wear to obtain). On the other hand, the length of the plunger 14 must be sufficiently large. In the exemplary embodiment, it is 400 to 600 mm. Advantageously, the two ends of the plunger are close to the center of rotation of the roller-side spindle head. The relative movements in the contact areas between bearing elements 12, 13 and plunger 14 are smallest, when the plunger 14 is installed centrally to the center of rotation of the spindle head. A calotte-shaped ram end that would lie exactly in this center of rotation would experience a relative movement in the form of a wobbling movement corresponding to the tilt angle α of the spindle, while the other ram end would not be subject to any relative movement. If the plunger ends are arranged centrally to or equidistant from the center of rotation of the spindle head, they each experience relative rotations corresponding to half the spindle angle.

On the one hand to achieve high reliability of the system and on the other hand to prevent the risk of buckling of the plunger 14, the ratio of the length L of the plunger 14 to its diameter D - s. Fig. 5 - between 4 and 10, preferably between 5.5 and 8.5. In Fig. 1a and 1b can be seen that in the (right) end portion of the axially movable shaft 5, a bearing body 21 is arranged (shown in detail in Fig. 6). On the non-co-rotating part of the bearing body 21, so on the outside of the body, acts not shown lever mechanism, the so-called. Balancing. With the balancing, which is already known as such, vertical and horizontal forces can be applied. With axial displacement of the roller 6 in the direction of the center of the roll stand (to the left), there is a risk that the spindle head 8 is pulled down by the flat pin 9 of the roll impact 7. In order to avoid this, one part of the articulated spindle is pressed with balancing in the direction of the roller 6. Those compressive forces that are not consumed by the friction in length compensation, are forwarded via the plunger 14 to the roller 6. After the axial displacement is finished towards the middle of the frame, the axial Balancierkraft can be reduced.

The axial balancing force should act in full only at an axial displacement towards the center of the frame. Otherwise, the force on the plunger 14 would double when displaced in the opposite direction. In case of incorrect control of this process, the wear on the plunger 14 and at the bearing points of the bearing elements 12, 13 increases. Slippage of the roller-side spindle head from the hit, however, in contrast to previously known solutions not to be feared when the cylinder for horizontal balancing so constructed is that it can only apply pressure forces and when its hydraulic pressure is coupled to the hydraulic pressure on the Axialverschiebezylinder the roller 6.

It can be seen in FIGS. 7 and 8 that the plunger 14 need not only be designed as in FIGS. 3 and 5. In the solution according to FIGS. 7 and 8, the plunger 14 consists of several parts, namely of a rod element 26, at the two axial end depending a plunger head 27 and 28 is mounted. The two plunger heads 27, 28 are by means of screw 29 on Rod member 28 attached. This results in the possibility of replacing only individual parts, ie only a plunger head when worn.

The bolted to the rod member 26 plunger head 27 and 28 can be secured with a fuse 31 against unintentional release.

An improvement in the cooling is achieved in the solution according to FIG. 7 and FIG. 8 in that a ribbing 30 - realized here only for the plunger head 27 - is arranged on the plunger head 28. Thus, as is known, the heat dissipating surface is increased.

The friction between the spherical plunger ends and the bearing elements 12, 13 resulting frictional heat can be reduced by a favorable design of the plunger or removed by an internal and / or external cooling with a medium (cooling air, cooling water, etc.). Bronzes can be envisaged as material for the bearing elements 12, 13 since they can dissipate the heat very well. However, this material has its limit in wear resistance. Carbon fiber composite materials may also be provided as material for the bearing elements 12, 13, which have high-strength properties. However, there are limits due to the relatively poor thermal conductivity of this material. For cooling or lubrication fats can be used, however, should be as temperature stable as possible because of the high temperatures at the contact point between bearing elements 12, 13 and plunger 14.

The proposed invention is characterized by a perfect kinematics of the components and by a simple and spatially compact design. Thus, a cost-effective implementation is possible. An internal and / or external cooling in particular of the contact point between the bearing element 12, 13 and plunger 14 supports the performance of the construction. LIST OF REFERENCE NUMBERS

1 drive spindle

2 drive motor

3 first wave

4 swivel joint

5 second wave

6 roller

7 roller hits

8 roller-side spindle head

9 flat pin

9a sliding block

9b sliding block

10 axis of rotation of the roller

11 axis of rotation of the second shaft

12 bearing element

13 bearing element

14 pestles

15 end of the plunger

16 end of the plunger

17 recess

18 means for captive placing the plunger

19 lubricant channel

20 longitudinal bore

21 bearing body for balancing

22 ring

23 fuse element

24 blocking element

25 advantage 26 rod element

27 ram head

28 ram head

29 screw connection

30 ribbing

31 fuse

α tilt angle

L length of the plunger

D Diameter of the plunger

R radius

Claims

claims:

A drive spindle (1) for the main drive of a roll stand, comprising:

a first shaft (3) for transmitting a torque from a drive motor (2) to a coupling element, in particular to a splined profile, and

a second shaft (5) for transmitting the torque from the coupling element, in particular the splined profile, via a rotary joint (4) to a roll (6) of the roll stand,

the swivel joint (4) having a roller impact (7) which is non-rotatably connected to the roller (6) and a second spindle head (8) which is non-rotatably connected to the second shaft (5), and

wherein the rotary connection between roll hit (7) and spindle head (8) by sliding blocks and a pin (9) is produced, which is non-rotatably connected to the spindle head (8), but a tilt angle (α) between the axis of rotation (10) of the roller (10) 6) and the axis of rotation (11) of the second shaft (5) is mounted permitting,

characterized,

a bearing element (12, 13) for absorbing forces in the direction of the axes of the second shaft (5) and the roller (6) is arranged between the roller impact (7) and the spindle head (8), wherein between the two bearing elements (12 , 13) a plunger (14) for transmitting axial forces between the roller hit (7) and the spindle head (8) is arranged.

2. Drive spindle according to claim 1, characterized in that the bearing elements (12, 13) concentric with the respective axes of rotation (10, 11) of the roller (6) and the second shaft (5) are arranged.

3. Drive spindle according to claim 1 or 2, characterized in that the bearing elements (12, 13) together with the plunger (14) each form a sliding bearing.

4. Drive spindle according to one of claims 1 to 3, characterized in that the bearing elements (12, 13) in the contact region with the plunger (14) in section have a concave shape and the end regions (15, 16) of the plunger (14) a having the concave shape corresponding convex shape.

5. Drive spindle according to claim 4, characterized in that the bearing elements (12, 13) in the contact region with the plunger (14) have in section substantially the shape of a hemisphere.

6. Drive spindle according to one of claims 1 to 5, characterized in that the pin (9) is substantially plate-shaped and has a recess (17) for the passage of the plunger (14).

7. Drive spindle according to claim 6, characterized in that the recess (17) has a conical shape.

8. Drive spindle according to one of claims 1 to 7, characterized by

Means (18) with which the plunger (14) captive with the roller hit (7) and / or with the spindle head (8) is connected.

9. Drive spindle according to one of claims 1 to 8, characterized in that the plunger (14) is pin-shaped.

10. Drive spindle according to claim 9, characterized in that the ratio of the length (L) of the plunger (14) to its diameter (D) is between 4 and 10, preferably between 5.5 and 8.5.

11. Drive spindle according to one of claims 5 to 10, characterized in that the radius (R) of the hemisphere of bearing elements (12, 13) and plunger (14) between half and the double ram diameter (D).

12. Drive spindle according to one of claims 1 to 11, characterized in that in the contact region between at least one of the bearing elements (12, 13) and the plunger (14), a lubricant channel (19) passing through the spindle head (8) opens, via which lubricant can be supplied to the contact region.

13. Drive spindle according to claim 12, characterized in that only in the contact region between one of the bearing elements (13) and the plunger (14) of the lubricant channel (19) opens and that the plunger (14) passing through it a longitudinal bore (20) for conveying of lubricant in the region of the other bearing element (12).

14. Drive spindle according to one of claims 1 to 13, characterized in that the bearing elements (12, 13) consist of a self-lubricating material, in particular of a graphite-containing material.

15. Drive spindle according to one of claims 1 to 14, characterized in that on or on the first shaft (3) a bearing body (21) is arranged, which is suitable for applying Balancierkräften on the second shaft (5).

16. Drive spindle according to one of claims 1 to 15, characterized in that the plunger (14) consists of a plurality of interconnected components (26, 27, 28).

17. Drive spindle according to claim 16, characterized in that the plunger (14) consists of a rod element (26), at whose ends in each case a plunger head (27, 28) is arranged.

18. Drive spindle according to claim 16 or 17, characterized in that the components (26, 27, 28) with a screw connection (29) are interconnected.

19. Drive spindle according to one of claims 1 to 18, characterized in that the plunger (14), in particular in the region of its axial ends, ribs (30).

20. Drive spindle according to one of claims 1 to 19, characterized in that the plunger (14) has at least one bore for passing a cooling medium.

21, drive spindle according to claim 20, characterized in that at least one bore for passing a cooling medium in the axial end region of the plunger (14).