ROLLER GROUPS FOR GRINDING DEVICES, GRINDING DEVICES, AND METHODS

Abstract

Roller packages (IO) for grinding devices (70), comprising a first roll (11), which is maintained by at least one first bearing body (13), and a second roll (12), which is maintained by at least one second bearing body (14). The first bearing body (13) and the second bearing body (14) are prestressed against each other and comprise stop elements (17,19) with stop surfaces (18, 20), the contact of which counteracts a contact of the rolls (11, 12). The rotational position of the first stop element (17) determines the minimum width of the grinding gap. Also disclosed are grinding devices (70), methods for operating a roll assembly (10) and methods for determining the radial force acting between the rolls (11, 12) of a roll assembly (10).

Claims

1-17. (canceled)

18. A milling apparatus (70), in particular a mill roll frame (70), comprising a machine stand (71) and at least one roll assembly (10) with a first roll (11) and a second roll (12) that is or can be inserted in the machine stand (71), wherein the roll assembly has an integrated rolling device (30) having at least one roller (31) which is or can be arranged on the roll assembly (10) in such a way that the roll assembly can be placed onto a horizontal base and moved thereon by means of the at least one roller (31), wherein the machine stand (71) has at least one rail (72) on which the at least one roller (31) of the roll assembly (10) is movable during mounting and/or demounting of the roll assembly (10), the roll assembly (10) has at least one contact surface (42, 76) and the machine stand (71) has at least one counter-contact surface (73), characterized in that the contact surface (42, 76) and the counter-contact surface (73) are tailored to one another and to the at least one rail (72) in such a way that, in a mounted position of the roll assembly (10), by virtue of at least one form-fitting engagement between the at least one contact surface (42, 76) and the at least one counter-contact surface (73), the at least one roller (31) of the roll assembly (10) does not lie on the rail (72).

19. The milling apparatus (70) according to claim 18, wherein the first roll (11) is held by at least one first bearing body (13), and the second roll (12) is held by at least one second bearing body (14), wherein the first bearing body (13) and the second bearing body (14) are adjustable relative to one another in such a way that a milling gap formed between the first roll (11) and the second roll (12) is adjustable, wherein the first bearing body (13) and the second bearing body (14) can be pretensioned with respect to one another by means of a tensioning device (16) in such a way that the first roll (11) and the second roll (12) are pressed towards one another, wherein the first bearing body (13) has at least one first abutment body (17) with a first abutment surface (18), and the second bearing body (14) has at least one second abutment body (19) with a second abutment surface (20), the abutment surfaces (18, 20) are formed and are or can be arranged on the bearing bodies (13, 14) in such a way that a contact of the abutment surfaces (18, 20) counteracts a contact of the rolls (11, 12), the first abutment body (17) is rotatable about a first axis of rotation (A1), and the first abutment surface (18) is formed by a circumferential surface (18) of the first abutment body (17) that is eccentric with respect to the first axis of rotation (A1), with the result that the rotational position of the first abutment body (17) determines the minimum width of the milling gap.

20. The milling apparatus (70) according to claim 19, wherein the second abutment body (19) is rotatable about a second axis of rotation (A2) which is parallel to the first axis of rotation (A1), and the second abutment surface (20) is formed by a circumferential surface (20) of the second abutment body (19) that is rotationally symmetrical with respect to the second axis of rotation (A2).

21. The milling apparatus (70) according claim 19, wherein the first axis of rotation (A1) of the first abutment body (17) and/or the second axis of rotation (A2) of the second abutment body (19) are/is arranged displaceably, in particular in a direction perpendicular to the first axis of rotation (A1).

22. The milling apparatus (70) according to claim 19, wherein the roll assembly (10) has a handwheel (21) which can be rotated about a handwheel axis of rotation (H) and which is coupled via a handwheel gear mechanism (22) to the first abutment body (17) in such a way that a rotation of the handwheel (21) causes a rotation of the first abutment body (17).

23. The milling apparatus (70) according to claim 19, wherein the roll assembly (10) has a force-measuring device which comprises: a first sensor (24) for directly or indirectly determining a first force with which the first bearing body (13) and the second bearing body (14) are pretensioned with respect to one another; a second sensor (25) for directly or indirectly determining a second force with acts between the first abutment body (17) and the second abutment body (19).

24. The milling apparatus (70) according to claim 18, wherein the roll assembly (10) comprises a handwheel (21) which is rotatable about a handwheel axis of rotation (H) and by means of which a milling gap formed between the first roll (11) and the second roll (12) can be set, wherein the roll assembly (10) has a position indicator (26) for indicating a position of the handwheel (21), and the position indicator (26) comprises a position indicator housing (27) and an indicator element (28) which is movable along the handwheel axis of rotation (H) relative to the position indicator housing (27) and which is or can be pretensioned by means of a position indicator spring (29) in the direction of the handwheel axis of rotation (H) with respect to the position indicator housing (27) in such a way that it can be rotated about the handwheel axis of rotation (H) only upon overcoming the pretensioning brought about by the position indicator spring (29).

25. The milling apparatus (70) according to claim 24, wherein the roll assembly (10) has an integrated rolling device (30) having at least one roller (31) which is or can be arranged on the roll assembly (10) in such a way that the roll assembly (10) can be placed onto a horizontal base and moved thereon by means of the at least one roller (31).

26. The milling apparatus (70) according to claim 24, wherein at least one of the bearing bodies (13, 14) has a rolling bearing (58) which supports a roll stub (33) of one of the rolls (11, 12), wherein a bearing cover (63) of the rolling bearing (58) has on its inner side (34) a guide channel (35) for lubricant that extends around the roll stub (33) and is connected to an outlet opening (36) through which lubricant can exit the guide channel (35).

27. The milling apparatus (70) according to claim 24, wherein the first roll (11) is held by two first bearing bodies (13), the second roll (12) is held by two second bearing bodies (14), and the first bearing bodies (13) are adjustable independently of one another and/or the second bearing bodies (14) are adjustable independently of one another.

28. The milling apparatus (70) according to claim 18, wherein the machine stand (71) has a tensioning device (16), and the roll assembly (10) has a coupling device (66) which is arranged in particular on the second bearing body (14) and intended for releasably coupling the roll assembly (10) to the tensioning device (16).

29. The milling apparatus (70) according to claim 28, wherein the tensioning device (16) has a cylinder (40), in particular a bellows cylinder (40).

30. The milling apparatus (70) according to claim 28, wherein the tensioning device (16) has at least one pretensioned spring (41) which is in particular connected in series with the cylinder (40).

Description

[0045] The invention will be explained below with reference to an exemplary embodiment and a number of drawings, in which

[0046] FIG. 1: shows a roll assembly according to the invention in a moved-out position with a part of a tensioning device;

[0047] FIG. 2: shows the roll assembly according to the invention in a moved-in position with the part of the tensioning device;

[0048] FIG. 3a: shows a mill roll frame according to the invention with two roll assemblies according to the invention in a perspective view;

[0049] FIG. 3b: shows the mill roll frame according to the invention in a side view;

[0050] FIG. 3c: shows the mill roll frame according to the invention in a plan view;

[0051] FIG. 4: shows a mill roll frame according to the invention with a roll assembly according to the invention in a side view;

[0052] FIG. 5: shows a detail view of a handwheel and of a handwheel gear mechanism for finely setting the gap width;

[0053] FIG. 6: shows a detail view of a position indicator for indicating a position of the handwheel;

[0054] FIG. 7: shows a detail view of two force sensors for determining the force acting between the rolls;

[0055] FIG. 8: shows a detail view of the roll assembly for adjusting the bearing bodies;

[0056] FIG. 9: shows a sectional view through a rolling bearing of the roll assembly;

[0057] FIG. 10: shows a perspective view of the roll assembly with a collection trough for lubricant;

[0058] FIG. 11: shows a detail view of a rolling device of the roll assembly with rollers and contact surfaces;

[0059] FIG. 12: shows a detail view of the machine stand with rails and counter-contact surfaces.

[0060] FIGS. 1 and 2 show a roll assembly 10 for a mill roll frame in a side view. The roll assembly 10 comprises a first roll 11, which is held by two first bearing bodies 13, and a second roll 12, which is held by two second bearing bodies 14. The second bearing bodies 14 are pivotably supported on the first bearing bodies 13 via pivot bolts 57.

[0061] The mill roll frame 70 illustrated in FIGS. 3a to 3c has a machine stand 71 and two roll assemblies 10 which are arranged above one another and thus in a space-saving manner. Each roll assembly 10 can be driven by means of a gear mechanism 43 which comprises a bearing housing 44 in which an input shaft (not visible here), a first output shaft 46 and a second output shaft 47 are accommodated. The input shaft and the first output shaft 46 are arranged perpendicular to one another, and the first output shaft 46 and the second output shaft 47 are arranged parallel to one another. The input shaft and the first output shaft 46 are operatively connected to one another via a bevel gearwheel pair (not visible here), and the first output shaft 46 and the second output shaft 47 are operatively connected to one another via a torque transmission arrangement (likewise not visible). The first output shaft is coupled to the first roll 11, and the second output shaft 47 is coupled to the second roll 12. For a detailed description of the gear mechanism 43, reference is made to the already mentioned international patent application PCT/EP2018/061793. The gear mechanism 43 allows the movable mounting of the second roll 12.

[0062] The first bearing body 13 further has a first abutment body 17 which can be rotated about a first axis of rotation A1 and which has a first abutment surface 18. The latter is formed by a circumferential surface 18 of the first abutment body 17 that is eccentric with respect to the first axis of rotation A1. The second bearing body 14 has a second abutment body 19 which can be rotated about a second axis of rotation A2 parallel to the first axis of rotation A1 and which has a second abutment surface 20. The latter is formed by a circumferential surface 20 of the second abutment body 19 that is rotationally symmetrical with respect to the second axis of rotation A2. The two abutment surfaces 18, 20 are formed and arranged on the bearing bodies 13, 14 in such a way that a contact of the abutment surfaces 18, 20 counteracts a contact of the rolls 11, 12, as will be explained below.

[0063] FIG. 1 illustrates a moved-out position of the roll assembly 10 in which the abutment surfaces 18, 20 are not in contact with one another. By means of a tensioning device 16, which is a constituent part of the machine stand 71 and is only partially illustrated here, the first bearing body 13 and the second bearing body 14 are adjustable relative to one another in such a way that a milling gap formed between the first roll 11 and the second roll 12 can be adjusted. The tensioning device 16 comprises a tension anchor 51, a tension bush 55 pivotably mounted on an upper end 67 of the tension anchor 51 via an articulation 54, a tension rod 52 partially accommodated in the tension bush 55 and pretensioned by means of a disk spring assembly 41, and a bellows cylinder 40 which is coupled to a lower end 68 of the tension anchor 51 and is illustrated only in FIG. 4. The tension rod 52 is coupled to the second bearing body 14 by a coupling device 66 arranged on the second bearing body 14. The tension anchor 51 is supported on the first bearing body 13 at a supporting point 75 as long as the roll assembly 10 is installed.

[0064] FIG. 4 shows a lateral view of a mill roll frame 70 with the roll assembly 10. By activating the bellows cylinder 40, the lower end 68 of the tension anchor 51 is pressed against the first bearing body 13 and supported thereon, with the result that the overall torque acting on the roll assembly 10 is reduced. Here, the tension anchor 51 is pivoted about the supporting point 75 and thus pulls on the tension bush 55 and on the tension rod 52 and thus via the coupling device 66 on the second bearing body 14. In this way, the first bearing body 13 and the second bearing body 14 are pretensioned with respect to one another in such a way that the first roll 11 and the second roll 12 are pressed toward one another.

[0065] The bearing via the bellows cylinders 40 produces an overload safeguard. In order in an overload situation (for example upon a foreign body entering the milling gap) to allow an immediate load relief, the bellows cylinder is coupled to a sufficiently dimensioned venting valve in order to be able to rapidly reduce the pressure prevailing in the bellows cylinder by opening the venting valve. Without opening the venting valve, there would also result a force increase, but this would be substantially lower than if only a spring assembly were present.

[0066] The moved-in position of the roll assembly 10 that is illustrated in FIG. 2 is achieved when the abutment surfaces 18, 20 come into contact with one another. If the force prevailing in the milling gap varies, only the pretensioning force between the bearing bodies 13, 14 changes, but not the relative position thereof. The rotational position of the first abutment body 17 determines the minimum width of the milling gap.

[0067] In order to be able to roughly set the width of the milling gap, the first axis of rotation A1 of the first abutment body 17 and the second axis of rotation A2 of the second abutment body 19 are arranged displaceably, to be precise in a direction perpendicular to the axes of rotation A1, A2.

[0068] The roll assembly 10 further has, for fine-setting of the width of the milling gap, a handwheel 21 which can be rotated about a handwheel axis of rotation H. The handwheel 21 is coupled to the first abutment body 17 via a handwheel gear mechanism 22 illustrated in FIG. 5. It is constituted in such a way that a rotation of the handwheel 21 causes a rotation of the first abutment body 17. It is thus possible for a comparatively small torque on the handwheel 21 to be converted into a large torque at the first abutment body 17. For the aforementioned purposes, the handwheel gear mechanism 22 has a high efficiency and a small gear mechanism backlash.

[0069] The roll assembly 10 further has a position indicator 26, which is shown in detail in FIG. 6, for indicating a position of the handwheel 21. The position indicator 26 comprises a position indicator housing 27 and an indicator element 28 which is movable along the handwheel axis of rotation H relative to the position indicator housing 27. The indicator element 28 is or can be pretensioned by means of at least one position indicator spring 29 in the direction of the handwheel axis of rotation H with respect to the position indicator housing 27 in such a way that it can be rotated about the handwheel axis of rotation H only upon overcoming the pretensioning brought about by the position indicator spring 29. This occurs by means of form-fitting elements 53 on the indicator element 28 and on the position indicator housing 27.

[0070] To determine the radial forces prevailing between the rolls 11, 12, the roll assembly 10 comprises a force-measuring device which comprises a first force sensor 24 and a second force sensor 25. The first force sensor 24 is integrated in the tensioning device 16, namely in the region of the articulation 54 formed between the tension anchor 51 and the tension rod 52; the second force sensor 25 is situated on the second abutment body 19 (see FIG. 7). In this way, the first sensor 24 can be used to determine a first force with which the first bearing body 13 and the second bearing body 14 are pretensioned with respect to one another, and the second sensor 25 can be used to determine a second force which acts between the first abutment body 17 and the second abutment body 19. From these forces there can be computationally determined the force acting between the rolls 11, 12.

[0071] FIG. 8 illustrates in detail how the second bearing bodies 14 are pivotably supported on the first bearing bodies 13 via pivot bolts 57. The first bearing bodies 13 each contain a wedge 39 through which an adjusting screw 56 is guided. A rotation of the adjusting screw 56 produces a displacement of the wedge 39 in a horizontal first direction R1 and hence a displacement of the pivot bolt 57 and of the second bearing body 14 in a second direction R2, which is vertical to the first direction R1. In this way, the second bearing bodies 14 are individually adjustable relative to the first bearing bodies 13, thus allowing tilting of the roller axes.

[0072] FIGS. 9 and 10 show in detail a rolling bearing 58 and the sealing thereof. A roll stub 33 of the second roll 12 is supported by an inner ring 59, a plurality of rolling bodies 60 and an outer ring 61. In the axial direction thereof there are situated an inner bearing cover 62 and an outer bearing cover 63 which on their inner sides 34 have grooves 64, which extend around the roller stub 33, for seals (not shown here) and guide channels 35 for lubricant. Also present are shoulders 65 which assist in slinging away the lubricant. The guide channel 35 of the outer bearing cover 63 is connected to an outlet opening 36 through which lubricant can exit the guide channel 35 of the outer bearing cover 63. Underneath the outlet opening 36 there is situated a collecting device 37 for collecting the lubricant, which is designed in the form of a trough 37. There is a connecting bore (not shown) between the interior and the guide channel 35 in order to prevent over-greasing and thus allow excessive grease to escape through this connecting bore. The mill roll frame 70 can be hygienically operated as a result.

[0073] As shown in FIG. 11, the roll assembly 10 has an integrated rolling device 30 with rollers 31. The rollers 31 are arranged on the roll assembly 10 in such a way that the roll assembly 10 can be placed on a horizontal base (not shown here) and moved thereon by means of the rollers 31. As shown in FIG. 12, the machine stand 71 of the mill roll frame 70 has rails 72 on which the rollers 31 of the roll assembly 10 can move during mounting and/or demounting of the roll assembly 10. The roll assembly 10 further has front contact surfaces 76 (see FIG. 8) and rear contact surfaces 42, and the machine stand 71 has corresponding counter-contact surfaces 73. The contact surfaces 42, 76 and the counter-contact surface 73 are tailored to one another and to the rails 72 in such a way that, in a mounted position of the roll assembly 10, by virtue of a form-fitting engagement between the contact surface 42, 76 and the counter-contact surface 73, the rollers 31 do not lie on the rail 72.