AU741638B2 - Device for the crossed displacement of the rolling rolls - Google Patents

Description

1

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name of Applicant/s: Actual Inventor/s: Address of Service: Danieli C. Officine Meccaniche SpA Fausto DRIGANI, Giacinto DAL PAN and Cesare

GALLETTI

SHELSTON WATERS MARGARET STREET SYDNEY NSW 2000 1, Invention Title: "DEVICE FOR THE CROSSED DISPLACEMENT OF THE ROLLING ROLLS" The following statement is a full description of this invention, including the best method of performing it known to us:- (File: 20422.00) 11 t la- "DEVICE FOR THE CROSS DISPLACEMENT OF THE ROLLING ROLLS" This invention concerns a device for the crossed displacement of the rolling rolls in a four-high rolling stand as set forth in the main claim.

The invention is applied in cooperation with the upper and lower rolling blocks of a four-high rolling stand for sheet and/or strip for the crossed and coordinated displacement of the working rolls and/or the back-up rolls.

The invention also includes means to compensate the moment of traversing acting on the chocks of the back-up rolls and working rolls which are made to cross over due to the eccentricity which is created between the load force and the rolling thrust.

Moreover, the invention provides sliding means for the chocks during the crossed displacement of the rolls under load.

The following discussion of prior art is not to be construed as an admission with regard to the common general knowledge in Australia.

The state of the art covers four-high rolling mill stands for sheet and/or strip which 15 include counter-opposed working rolls defining the rolling plane and mounted on relative chocks, each working roll being associated with a back-up roll which limits the bending of the working rolls during the rolling step.

It is known that it is necessary to induce on the rolls a displacement on the rolling plane which will cause a reciprocal, crossed positioning.

There have been proposals for a plurality of systems to displace the chocks, for example using systems with gears, screws, jacks and others.

However, these systems have not proved satisfactory with regard to accuracy of positioning, coordination of movement, simplicity of embodiment and application, installation costs, and also for other reasons, including the quantity of 2 1 power required, the considerable bending caused, the 2 incorrect working of the bearings, etc.

3 Moreover, these systems known to the state of the art 4 require very long and laborious inspection and/or maintenance times, both because of their complex embodiment 6 and also because they are placed where it is difficult for 7 the workers to gain access to them, or where they may be 8 reached only after preliminary operations of at least 9 partial dis-assembly of the rolling stand, which must be done when the plant is shut down, with all the technical and 11 economic problems which this entails.

12 It is also known that, during the crossed displacement of 13 the rolls, a moment of traversing is generated on the chocks S 14 of the back-up rolls; this is caused by the misalignment of S* 15 the thrust forces which the rolled stock impresses on the 16 rolls with respect to the load exerted by the hydraulic 17 pressure means acting on the chocks of the back-up rolls.

18 This moment of traversing generates considerable friction 19 which leads to wear and malfunctions of the rolling stand.

20 Moreover, this friction increases the mechanical 21 hysteresis of the system to automatically adjust the 0.

22 thickness, so that it is impossible to accurately control 23 the thickness and profile of the rolled stock.

24 Another problem is the rolling thrust forces which o 25 generate friction between the chocks of the upper and lower 26 back-up rolls and the respective organs, such as millscrews, 27 hydraulic actuator capsules, spacers, etc., which discharge 28 the rolling force onto the housing of the rolling mill 29 stand.

This friction contrasts the pair crossing movement and 31 makes it difficult to carry out under load; this, however, 32 is indispensable in the case of the continuous rolling of 33 sheet or large plate.

It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.

DISCLOSURE OF THE INVENTION Accordingly, the invention provides a device for the crossed displacement of rolling rolls, whether they be working rolls and/or back-up rolls, in a rolling stand for sheet and/or strip, the rolls being supported at the ends by respective supporting chocks associated with stationary housing means, the device comprising means cooperating with at least one side wall of at least one chock and exerting a thrust action against the wall to achieve a lateral displacement on the rolling plane of the chock and of the roll associated therewith, at least a compensation device to compensate the moment of traversing, caused by the eccentricity between the load force and the rolling thrust, cooperating with the upper or lower side of at least one chock of a back-up roll and anti-friction sliding means arranged at least between the upper face of the upper back-up roll and the means 0% g o to adjust the rolling load.

15 Unless the context clearly requires otherwise, throughout the description and the claims, the words 'comprise', 'comprising', and the like are to be construed in an .inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense ooo.

00of "including, but not limited to".

Advantageously, the invention, at least in a preferred form provides a device for the crossed displacement of the rolling rolls which is simple in construction and in working, suitable to cause precise, controlled and coordinated displacements of the rolls.

More advantageously, the invention compensates for the moment of traversing which acts on the chocks of the back-up rolls in the rolling stands when the rolls are moved with a crossing movement.

Further, advantageously, the invention provides sliding means, cooperating with the chocks, which will make it possible to carry out the crossed displacement of the rolls even during the rolling step, thus considerably reducing or cancelling the forces of friction which contrast this pair crossing movement.

Advantageously, the invention, in a preferred form makes it possible to obtain the crossed positioning of the rolls of a rolling stand, and to maintain this position for the desired time, imparting to the first end of a roll movements in the opposite direction to those imparted to the opposite end of the same roll and to those imparted to the corresponding ends of the counter-opposed roll.

The device according to a preferred embodiment of the invention, comprises front cam means arranged in a position of substantial contact with a side wall of the chock; S* when the front cam means are made to rotate, they impart to the chock the desired oo** movements of lateral displacement.

•Preferably, the front cam means include at least two principles.

According to a variant, the plane of inclination of the front cam principles is a plane which allows a stable stop and therefore does not create any inverse rotation which Imight modify the position reached.

*ooo Preferably, the front cam means are governed by motor means which when oo o activated determine the direction of the movements of lateral displacement imparted by the front cam means to the ends of the rolls.

According to a variant, there are front cam means on both fronts of the rolling stand and they act on both ends of the rolling rolls.

According to another variant, there are front cam means only on one front of the ,rolling stand and they act on only one end of the rolls.

According to another preferred embodiment of the invention, there are intermediate positioning elements associated with the chocks which cooperate with slider elements governed by motor means.

Preferably, the cooperating surfaces of the intermediate positioning elements and the slider elements define inclined planes placed in reciprocal contact in such a way that longitudinal movements imparted to the slider elements are transformed into movements of lateral displacement of the intermediate positioning elements.

Preferably, the slider elements are moved by means of a threaded shaft driven by the motor means.

to Preferably, for each rolling block, upper or lower, the slider element associated :with the back-up roll cooperates with the threaded shaft by means of a thread which is threaded in the opposite direction to that of the slider element associated with the *working roll of the same rolling block.

Preferably, the inclined plane surfaces which generate the lateral or horizontal 1. 5 displacement of the intermediate positioning elements, according to the lengthwise S displacement of the relative slider elements, have an.opposite inclination.

Advantageously, the combination of the orientation of the threads which connect o.:o the slider elements to the drive shaft and the inclination of the relative inclined plane °ooo surfaces makes it possible to obtain the desired crossed displacements of the rolling rolls of counter-opposed rolling blocks in an extremely precise and measured manner.

In another preferred embodiment the intermediate positioning elements are associated with movement means located in a position outside the stationary housing and therefore easily accessible for the worker; this facilitates simple and rapid operations of Sinspection, maintenance and calibration, and also simplifies the structure, improves the accuracy of positioning and the coordination of movements, and moreover reduces installation costs.

Preferably, the movement means are of the irreversible eccentric kind, and cooperate with arm means governed by drive means.

According to a variant, the eccentric means, or the intermediate positioning elements or the arm elements, are equipped with clamping means which can temporally clamp the rolls in any crossing position whatsoever they are in, in order to release the movement means so as to carry out maintenance operations.

According to a variant, between the intermediate positioning element and the stationary housing of the rolling stand there are compensation means suitable to prevent unwanted deformations and to compensate for any play.

According to a variant of the invention, in cooperation with the chocks of at least one back-up roll there is a compensation device consisting of a pair of actuators attached to the stationary housing of the rolling stand, each of which acts on one side of a 15 respective chock.

According to a variant, the actuators are located symmetrically on opposite sides eewith respect to the median plane of the rolling stand containing the longitudinal axes of eoee the rolls. According to another variant, there is a pair of actuators for each of the two o* chocks of one back-up roll.

Preferably, the pair of actuators exerts a push-and-pull action in correspondence with the upper outer face of the chocks.

According to a variant, the actuators are attached to the uprights of the rolling stand and act in correspondence with the lower face of the chocks of the upper back-up a roll.

-7- According to a variant, each of the actuators is equipped with an independent adjustment system which enables them to be activated in a reciprocally differentiated manner and with different working pressures.

According to another variant, the two actuators are governed by a control unit which monitors the parameters relating to the working conditions of the rolls and the crossover position thereof, and in particular the extent of the misalignment and the rolling force; the control unit orders the actuators to exert a differentiated push-and-pull action on the two ends of the roll, according to the intensity and direction of the moment of traversing acting on the relative chocks.

Preferably, the action of the compensation device cancels the unbalancing action of :the moment of traversing, which allows optimum rolling conditions to be obtained and attenuates the friction between the upper back-up roll and the chocks, thus reducing wear 0 aof the component parts of the latter and also limiting any deviations from the desired 00e thickness.

0 15 The action of the actuator means can also assume, in a variant, the function of oo balancing the upper back-up roll.

*ooo ~According to another preferred embodiment of the invention, there are anti-friction oooo elements interposed between the organs to adjust the clearance and those to transmit load oo 0 0 000 to the rolls (millscrews, capsules, spacers, etc.), and the outer face of the chock of the back-up roll to be displaced and in correspondence with which chock these organs act.

According to a further preferred embodiment of the invention, the anti-friction element is composed of a hydrostatic bearing inside which, before the crossing angle is varied, a desired value of pressure of the circulating liquid is obtained.

7a- The hydrostatic bearing preferably comprises a plurality of hydrostatic chambers or pockets defining a clearance between the organs to regulate the clearance and the outer face of the relative chock, the chambers or pockets being suitable to be filled with fluid at the desired pressure during the crossing of the rolls under load.

Advantageously, because of these hydrostatic chambers or pockets there is no contact and therefore no rubbing. In this way it is possible to avoid problems of premature wear, reduced accuracy of adjustment as time passes, the need for maintenance and the need to increase the force required by the organs which perform the crossing of the rolls.

According to another preferred embodiment of the invention, the anti-friction :elements consists of at least a circular sector of a conical or truncated cone roller bearing located between the organs to transmit the load and to regulate the clearance between the rolls and the relative outer face of the chock on which the organs act.

According to a variant, the rolls have a barrel conformation, the curvature of which 15 depends on the load which is applied and on the elastic yielding of the rolls.

According to another variant, there are pads with circulating small cylindrical .s irollers, the pads being *oo 8 1 substantially conical in conformation, being located 2 radially in a sector and having the extensions of their 3 relative axes intersecting substantially in correspondence 4 with a vertical axis passing through the mean point of the rolls.

6 According to a further variant, the anti-friction elements 7 are composed of barrel rollers arranged in a sector.

8 The attached figures are given as a non-restrictive 9 example and show some preferred embodiments of the invention as follows: 11 Fig.l is a part section view of part of a rolling stand S 12 using the device according to the invention in a first S13 embodiment; S14 Fig.2 shows part of a detail of the device according to the 15 invention;

S.

16 Fig.3 shows a lengthwise cross section of the enlarged 17 detail A of Fig. 1; 18 Fig.4 shows a diagram of a view of the lengthwise .19 development of Fig.3; Fig.5 shows a lengthwise cross section of the enlarged .21 detail B of Fig. 1; 22 Fig.6 shows a diagram of the lengthwise development of 23 24 Fig.7 shows a diagram of a compensation device applied to a rolling stand; 26 Fig.8 shows a diagram of a variant of Fig.7; 27 Fig.9 and 10 show in part section, respectively from the 28 front and from the side, another embodiment of the 29 device of Fig. 7; Fig.ll shows partly and in diagram form a rolling stand 31 using a variant of the device according to the 32 invention; 33 Fig.12 shows a cross section from A to A of Fig. 11; 9 1 Fig.13 shows a three-dimensional view of a part section of 2 a rolling stand with sliding bearings in a first 3 embodiment; 4 Fig.14 shows a diagram of a variant of the bearings shown in Fig. 13; 6 Fig.15 shows a front view of a rolling stand using another 7 embodiment according to the invention; 8 Fig.16 shows a part view of a variant of Fig. 9 The roll 10 of a rolling stand 11 for strip and/or sheet, partly shown in Fig. 1, has its ends associated with chocks 11 12 housed in the space delimited by a supporting stationary 12 housing 13.

13 The roll 10 shown in the Figure may represent either the 14 upper or lower back-up roll or working roll in a four-high 15 rolling stand.

S..

16 In the embodiment shown in Figs. 1-6, the stationary 17 housing 13 has through holes 14 which house the drive shafts 18 15 of front cam means 16 placed in direct cooperation with a 19 side wall of the relative chock 12.

The front cam means 16, as can be seen in Fig. 2, consist 21 of a first substantially cylindrical element 17, associated 22 with the relative drive shaft 15, cooperating with a mating S23 substantially cylindrical element 18 associated, either 24 directly or by means of intermediate elements to transmit *e e movement, with a chock 12 of the roll 26 The cylindrical elements 17 and 18 include front surfaces 27 of reciprocal contact 19 and 20 defining mating inclined 28 planes with a radial development and cooperating with each 29 other.

According to a variant, between the contact surfaces 19 31 and 20 there are anti-friction means such as bearings or 32 rollers, oil pads, low friction foils, etc.

33 The rotation imparted to the shaft 15, and therefore to 1 the cylindrical element 17, causes a sliding of the inclined 2 plane surfaces 19 of the cylindrical element 17 on the 3 mating inclined plane surfaces 20 of the cylindrical element 4 18. This determines on the cylindrical element 18 rectilinear movements of axial displacement in one direction 6 or the other, according to the direction of rotation of the 7 shaft 8 The front cam means 16 progressively assume a plurality of 9 positions between a first working position 16a, wherein the front cam means 16 has an overall minimum width SI, to a 11 second working position 16b, wherein the front cam means 16 1:.s 12 has an overall maximum width of S2.

0*13 In this way, since the cylindrical element 17 is free to Se 1 rotate but solidly constrained to the stationary housing 13, 15 the rectilinear movements of axial displacement of the 16 cylindrical elements 18 are transmitted directly to the 0**i 17 chocks 12 with which the cylindrical elements 18 are 18 associated.

19 In this case, the movement is transmitted by means of spherical or cylindrical joints 21 cooperating with mating 21 surfaces 22 on the cylindrical element 18.

22 The cylindrical element 18 also includes end-of-travel 23 means 23 which prevent the cylindrical element 17 from 24 performing rotation movements above the desired values.

25 In the case shown in Fig. i, the front cam means 16 have 26 been adjusted, by means of the counter-opposed drive of the 27 respective shafts 15, in such a way as to include, on 28 opposite sides of the chock 12, respectively a first working 29 position 16a and a second working position 16b actuating a crossed displacement of the roll 10 according to a desired 31 angle P. The drive shafts 15 are advantageously governed by 32 a control system so as to achieve coordinated and controlled.

33 displacements on opposite sides of the chock 12.

11 1 In one embodiment of the invention, the front cam means 16 2 are on both fronts of the rolling stand 11.

3 According to a variant, the front cam means 16 are on only 4 one front of the rolling stand 11.

The rolling stand 11, as shown in Figs. 7-10, has a 6 compensation device 24 which, in this case, cooperates with 7 the chock 12 of the upper back-up roll 10. According to a 8 variant, there is an identical compensation device 24 9 cooperating with the lower back-up roll The compensation device 24 is used to limit and even 11 cancel the influence of the moment of traversing acting on S *12 each chock 12 generated by the eccentricity of the :00013 thrust force of the rolled stock passing through with 0 0014 respect to the load force exerted on the same chock 12 0:0000 15 by the adjustment means 6 8 16 The eccentricity is determined by the pair crossing 00..

17 position which the back-up rolls and working rolls assume in :00418 the course of rolling.

os 19 According to a first embodiment as shown in diagram form in Fig.7 and in greater detail in Figs. 9 and 10, the 21 compensation device 24 comprises a pair of actuators 26, 126 22 acting on each of the two chocks 12 in correspondence with 23 the outer upper face of the chocks 12.

"24 In this case the two actuators 26, 126 consist of jacks 27, with a rod 127, and are attached to the stationary 26 housing 13 in a symmetrical position with respect to the 27 median vertical plane of the stand, and act, with a drawing 28 action which generates forces indicated respectively as "K" 29 and on a plate element 28 which is made solid with the chock 12 by means of the relative arms 26a, 126a; the plate 31 element 28 can slide laterally in relation to these arms.

32 According to the invention, the actuators 26, 126 have a 33 reciprocally independent drive system and are connected to a 12 1 control and command unit, which is not shown here, and which 2 is able to monitor the working conditions of the rolling 3 assembly and the values of the load force the thrust 4 force and the eccentricity According to these parameters the control and command unit 6 activates the two actuators 26, 126 in a differentiated 7 manner, by altering the respective working pressures, moving 8 the chock 12 in such a way as to contrast and make 9 substantially ineffective the action of the moment of traversing acting on the chock 12.

11 The differentiated pressure exerted on the two opposite 12 sides of the chock 12 has the effect of compensating the Y% 13 traversing movement deriving from the misalignment between 14 the load and thrust force due to the passage of the e 15 rolled product.

16 The actuators 26, 126 are anchored to the respective *"17 uprights 20 of the stationary housing 13 by means of an e ee Z:18 assembly flange 29 and comprise a respective jack 27 with a 19 rod 127 anchored on one end of an oscillating lever element 20 30 pivoted at 31.

21 One end of the arm 26a, 126a is anchored at the other end 22 of the oscillating lever element 30; the other end of the 23 arm 26a, 126a is anchored to the chock 12 on which the upper 24 back-up roll 10 is assembled.

25 According to the variant shown in Fig.8, the jacks 27 0.

26 thrust against the lower outer face of each of the two 27 chocks 12, to which they remain clamped even during the 28 crossed displacement step of the relative back-up roll 29 In this case, the two jacks 27 are attached to bracket elements 32 solid with the uprights of the housing 13.

31 According to the invention the jacks 27 exert a 32 differentiated thrust action according to commands given by 33 a control unit; the thrust action generates forces indicated 13 1 respectively as on the chock 12 in order to 2 contrast and/or make substantially ineffective the moment of 3 traversing acting on the chock 12.

4 In the embodiment shown in Figs. 13 and 14, there are bearings 41 located in an intermediate position between a 6 distribution plate 12a, whose purpose is to distribute the 7 load over the whole width of the relative chock 12 of the 8 back-up roll 10 which is to be displaced, and the relative 9 hydraulic compression capsules 42 which act on the chocks 12.

11 In Fig. 13 the sliding bearings 41 consist of a 12 hydrostatic bearing 41a, solid with the hydraulic capsule 13 42, comprising one or more hydrostatic chambers or pockets eeeo 14 43 open on the upper surface of the distribution plate 12a S15 into which the pressure liquid is introduced.

.9 16 The hydrostatic chambers or pockets 43 define a clearance 17 44 which is thinner than the upper face of the distribution 9999 18 plate 12a of the relative chock 12.

S19 When a condition prevails whereby the rolling rolls 10 are 20 maintained in a stable crossover position, the pressure of 21 the liquid inside the bearing 41a is maintained 22 substantially nil, and the load is transmitted by the 23 hydraulic capsule 42 by means of direct contact between the 24 hydrostatic bearing 41a and the distribution plate 12a.

25 Before the crossed displacement of the rolling rolls .i 26 the pressure of the liquid inside the hydrostatic bearing 27 41a is increased, thus creating, in correspondence with the 28 open hydrostatic chambers or pockets 43, a layer of liquid 29 between the upper surface of the distribution plate 12a and the lower surface of the hydrostatic bearing 41a, the layer 31 of fluid completely filling the clearance 44.

32 This fluid diaphragm enables the rolling rolls 10 to be 33 displaced in conditions of substantially no friction between 14 1 the chock 12 and the hydraulic capsule 42, and particularly 2 without any contact, and therefore without any rubbing, and 3 in any case the transmission of the rolling load is 4 guaranteed.

The pressure of the liquid in the hydrostatic bearing 41a 6 is controlled by a control unit which, by monitoring the 7 parameters relating to the processing conditions and the 8 displacements of the rolls 10 which are to be carried out, 9 maintains the pressure or varies it in accordance with the appropriate desired values according to the rolling step, in 11 such a. way as to maintain substantially constant the 12 pressure load exerted on the product passing through.

13 In Fig. 14 the sliding bearings 41 substantially consist El 14 of a revolving bearing 41b with conical or truncated cone 15 rollers 45, which have the relative top facing the chock 12 :16 opposite the one with which they are associated.

0 00 17 The rollers 45 are arranged radially in an intermediate .oo.18 position of contact between the sliding elements, one :019 associated with the hydraulic capsule and the other 20 associated with the upper wall of the chock 12 of the upper 21 back-up roll.

22 The extensions of the axes 45a of the rollers 45 intersect 23 substantially on the vertical of the mean point of the roll 24 10 which is to be displaced, corresponding with the centre of rotation of the roll 10 during the pair crossing step.

26 Thanks to the rollers 45, the crossed displacement takes 27 place in conditions of substantially no friction, while the 28 conical shape of the rollers 45 ensures the absence of 29 rubbing on the horizontal plane of the chock 12.

According to a further variant which is not shown here, 31 the rollers 16 are barrel-shaped.

32 According to the variant shown in Figs. 11 and 12, in a 33 lateral position between the stationary housing 13 and the 15 1 chocks 12, there are intermediate positioning elements 33 2 cooperating with movement means 34.

3 The intermediate positioning elements 33 consist of plates 4 arranged with the inner face in contact with the side wall of the relative chock 12 and the outer face, facing the 6 inner wall of the stationary housing 13, conformed in a 7 double inclined symmetrical plane with a convergent 8 development.

9 A first part of the inclined plane cooperates with the chock 12 associated with the back-up roll 10 and a second 11 part of the inclined plane, which has an opposite, specular 12 inclination to the first part, cooperates with the chock 12 13 associated with the corresponding working roll 14 The movement means 34, in this case common to all the chocks 12, comprise motor means which cause a screw-type 16 drive shaft 35 to rotate; the screw-type drive shaft 35 acts 17 on sliding elements 36, arranged between the stationary 18 housing 13 and the relative intermediate positioning element 19 33.

20 In this case, there is a sliding element 36 for each of 21 the side walls of the chocks 12.

22 The sliding elements 36 have inclined plane front surfaces :23 36a cooperating with the respective inclined plane surfaces 24 of the outer face of the intermediate positioning elements 33.

26 The sliding elements 36 associated with the upper back-up 27 roll 10 are associated with the screw-type drive shaft 35 by 28 means of bush elements with threads 37a, for example a 29 right-hand thread, with an opposite direction to the thread 37b, which is therefore a left-hand thread, of the bush 31 which associates the screw-type drive shaft 35 with the 32 sliding element 36 associated with the corresponding working 33 roll 16 1 Since corresponding front surfaces 36a of the sliding 2 elements 36 cooperate with inclined plane surfaces having 3 opposite inclinations, the rotation of the screw-type drive 4 shaft 35 causes the back-up roll and the relative working roll to be displaced in the same direction.

6 Once the direction of rotation of the screw-type drive 7 shaft 35 has been defined, the opposed orientation of the 8 threads 37a, 37b causes an opposed vertical movement of the 9 relative sliding elements 36; when the sliding element 36 associated with the chock 12 of the back-up roll moves 11 downwards, the sliding element 36 associated with the chock 12 12 of the working roll moves upwards, and vice versa.

13 This opposite vertical movement, combined with the 14 opposite inclination of the inclined planes of the outer *outer 15 face of the intermediate positioning elements 33 with which 16 the front surfaces 36a of the sliding elements 36 cooperate, 17 causes the lateral displacement in the same direction of the 18 chocks 12 and therefore of the rolls 10 in the same rolling 19 block.

At the same time, the movement means 34 associated with 21 the other side of the chocks 12 are activated either by 22 making the relative screw-type drive shaft 35 rotate in an 23 opposite direction, or by including threads 37 in an 24 opposite direction to the bushes associated with the sliding S. 25 elements 36 which cooperate with the same chock 12.

26 Between the stationary housing 13 and the sliding surfaces 27 of the sliding elements 36 there are plate-type guide means 28 38 lined with an anti-friction material which facilitate the 29 movement of the sliding elements 36.

There are also plate-type adjustment means 39, associated 31 with screw-type adjustment means 40 which are solidly 32 attached to the stationary housing 13, which make it 33 possible to adjust the end-of-travel of the maximum lateral 17 1 displacement of the chocks 12.

2 According to a variant, the connection between the screw- 3 type drive shaft 35 and the sliding element 36 is achieved 4 by means of an inwardly threaded bush with a thread of circulating ball bearings.

6 In the embodiments shown in Figs. 15 and 16, the 7 intermediate positioning elements 33 cooperate with movement 8 means 34, which achieve a rod/crank configuration and 9 comprise irreversible eccentric means 46 connected to arms 47 associated with actuation bars 48 governed by jacks 49 11 mounted on the stationary housing 13.

12 The first arm 47 associated with the upper back-up roll o.o 13 is connected with the relative jack 49, while the other arms 14 47 are driven by the vertical movement of the actuation bar 48 which is solid with the first arm 47.

16 The point of connection between the jack 49 and first arm 17 47 is displaced towards the outside with respect to the 18 plane on which lie the centres of the eccentric means 46 in 19 such a way as to reduce the force required from the jack 49 oooo to move the intermediate positioning elements 33 laterally.

21 The circumferential displacements imparted to the arms 47 22 by the vertical movements of the actuation bars 48 are 23 transformed by the eccentric means 46 into horizontal 24 rectilinear movements of the rods 50 which are solidly attached to the intermediate positioning elements 33.

26 Appropriate sliding and guide means may be included to 27 facilitate the vertical movements of the actuation bars 48, 28 to prevent unwanted deformations and compensate for any 29 possible play.

The eccentric means 46 have their axis parallel to the 31 nominal horizontal axis of the rolls 32 According to a variant, the eccentric means 46 have their 33 axis vertical and substantially at right angles to the 18- 1 nominal horizontal axis of the rolls 2 The eccentric means 46 are configured in such a way as to 3 induce a coordinated movement such that the positioning of 4 the intermediate positioning element 33 on one side of the chock 12 corresponds to a positioning in the other direction 6 of the other intermediate positioning element 33 on the 7 other side of the chock 12.

8 Moreover, according to this configuration the intermediate 9 positioning elements 33 of the upper block receive a movement in the opposite direction to that imparted to the 11 elements 33 of the lower block, causing the desired crossed 12 positioning of the rolls 13 In the case shown in Fig.15, the upper block and the lower 14 block are associated with a single jack means 49 connected S 15 to an actuation bar 48 which induces an opposite 16 displacement to the elements of the upper block in relation 17 to those of the lower block.

18 This is because the arms 47 are anchored to the eccentric 19 means 46 at diametrically opposed points, at 1800 from each 20 other, between the upper block and the lower block.

21 In a similar way, the points of connection between the S. 22 arms 47 and the eccentric means 46 of opposite sides of the 23 same chock 12 are arranged diametrically opposed.

24 According to a variant, each rolling block, both upper and 25 lower, cooperates with a respective jack means 49, and the 26 connection between the arms 47 and the relative eccentric 27 means 46 of the upper rolling block is specular with respect 28 to the lower rolling block.

29 According to another variant, the intermediate positioning elements 33 associated with the back-up rolls 10 are 31 controlled by the same jack 49 by means of an actuation bar 32 48 associated with arms 47 connected to eccentric means 46 33 with diametrically opposed anchorage points; the working -19rolls 10 are associated with another jack 49 which is also connected to its own actuation bar 48 associated with eccentric means 46 with diametrically opposed anchorage points.

According to the further variant shown in Fig. 16, for each roll 10 there is a jack 49 which is directly associated with the eccentric means 46 by means of the arms 47, and in this case too the connection between the arms 47 and the eccentric means 46 is specular with respect to the upper and lower rolling block.

Whilst the invention has been described with reference to a number of specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.

o0 0o o:'oo oooo 1 ••go

Claims (13)

1. A device for the crossed displacement of rolling rolls, whether they be working rolls and/or back-up rolls, in a rolling stand for sheet and/or strip, the rolls being supported at the ends by respective supporting chocks associated with stationary housing means, the device comprising means cooperating with at least one side wall of at least one chock and exerting a thrust action against the wall to achieve a lateral displacement on the rolling plane of the chock and of the roll associated therewith, at least a compensation device to compensate the moment of traversing, caused by the eccentricity between the load force and the rolling thrust, cooperating with the upper or lower side of at least one chock of a back-up roll and anti-friction sliding means arranged at least between the upper face of the upper back-up roll and the means to adjust the rolling load. A device as in Claim 1, in which the means exerting a thrust action against at least one of the side walls of at least one chock comprise front cam means, whose axis lies on a plane substantially parallel to the rolling plane, associated with drive shafts, the front 15 cam means comprising at least two substantially cylindrical, coaxial elements, one connected to the drive shaft and the other cooperating with the chock, the front cam means including front surfaces of reciprocal connection defining inclined radial sliding planes with at least two principles, the rotation imparted to the front cam means being a function of the lateral displacement of the chock. 20 3. A device as in Claim 2, in which the front cam means include a first limit position of maximum compression wherein they assume a minimum width and a second limit position wherein they assume a maximum width. -21

4. A device as in Claim 2 or 3, in which, between the cylindrical element of the front cam means and the relative chock, there are means of a substantially spherical or cylindrical development to transmit movement. A device as in any one claim from 2 to 4 inclusive, in which the inclined plane front connection surfaces include end-of-travel means.

6. A device as in any one claim from 2 to 5 inclusive, in which there are anti-friction means between the front surfaces of reciprocal connection.

7. A device as in Claim 1, in which the means exerting a thrust action against at least one side wall of at least one chock comprise an intermediate positioning element with the inner lateral surface associated with the side wall of the chock and the outer surface, facing towards the wall of the stationary housing, with a double inclined plane inversely :orientated in a vertical direction, each inversely orientated part of the double inclined plane cooperating with a relative slider element including inclined plane front surfaces S-mating with the double inclined plane and sliding surfaces cooperating with the vertical 15 wall of the stationary housing, the sliding elements being associated with screw-type actuation means including, for each slider element associated with the same intermediate positioning element, connection threads of opposite orientation. see* 8. A device as in Claim 7, in which there are anti-friction guide means between the sliding surfaces of the sliding element and the stationary housing. o. 20 9. A device as in Claim 1, in which the means exerting a thrust action against at least one side wall of at least one chock comprise an intermediate positioning element associated with movement means outside the housing, the movement means comprising at least actuation means associated with bar means solid with eccentric means by means S of arm means, the eccentric means being associated with rod means which are movable 22 axially and orthogonally to the vertical plane of the stand and act on the intermediate positioning elements. A device as in Claim 9, in which the connection between the eccentric means and the relative arm means is specular, for each side of the rolling stand, between the upper and the lower block.

11. A device as in Claim 1, in which the compensation device comprises actuator means associated with at least one face of at least one chock and exerting on the chock a push-and-pull action associated with the crossover position of the roll in relation to the longitudinal median plane passing through the centre line of the rolling mill stand and/or associated with the value of the eccentricity.

12. A device as in Claim 11, in which the actuator means of the compensation device comprise, for each chock, a pair of jack screws attached to the stationary housing and Scooperating with the upper face of the relative chocks.

13. A device as in Claim 11, in which the actuator means of the compensation device 15 comprise, for each chock, a pair of jack screws attached to the side uprights of the housing and cooperating with the lower face of the relative chock.

14. A device as in any one claim from 11 to 13 inclusive, in which the actuator means of the compensation device have the function of balancing the upper back-up roll. 5. A device as in any one claim from 11 to 14 inclusive, in which the actuator means of the compensation device are governed by a control and coordination unit.

16. A device as in Claim 15, in which the control unit receives as input at least signals relative to the thrust force of the rolled product passing through, the load force imparted to the chocks, the misalignment or eccentricity and the actual forces of push-and-pull movement exerted by the actuators. 23

17. A device as in Claim 1, in which the anti-friction sliding means comprise one or more hydrostatic chambers or pockets arranged between the upper face of the chock and the means to adjust the rolling load, the hydrostatic chambers or pockets, opening onto their lower surface, to contain and limit the liquid, the hydrostatic chambers or pockets defining a clearance with respect to the upper face of the relative chock, the clearance being suitable to be filled with fluid which has a pressure functional to the current work step of the rolling stand.

18. A device as in Claim 1, in which the anti-friction sliding means comprise conical or truncated cone rollers arranged in an intermediate contact position between a sliding element solid with the chock and a sliding element solid with the stationary housing, the i top of the conical rollers facing the chock opposite the one with which they are associated and being disposed radially so as to define a circular sector the centre of **oo which is defined by the vertical projection of the centre of rotation of the relative back- up roll. 15 19. A device as in Claim 18, in which the rollers are barrel-shaped, are disposed radially in a sector and have the extensions of their axes intersecting in correspondence with a vertical axis passing through the mean point of the rolling rolls.

20. A device as in any one claim from 17 to 19 inclusive, in which the anti-friction 0000 00sliding means are associated with a distribution plate solid with the chock placed 00. 20 between the sliding means and the chock, substantially for the entire width of the said chock.

21. A device for the crossed displacement of rolling rolls said device substantially as -24- herein described with reference to any one of the embodiments of the invention as shown in the drawings. DATED this 1st Day of February, 2001 DANIELI C. OFFICINE MECCANICHE SpA Attorney: STUART M. SMITH Fellow Institute of Patent Attorneys of Australia of SHELSTON WATERS oo*