DEVICE AND METHOD FOR MILLING INPUT MATERIAL

Abstract

A roller press device for milling input material may include a fixedly mounted fixed roller having a roller shaft mounted at least approximately in a fixed position, a loosely mounted loose roller having a roller shaft that can be arranged in a variable position, a frame supporting at least the fixed roller and optionally also the loose roller, and a force application unit acting on the loose roller at a force application point. The fixed and loose rollers can be mounted and positioned relative to one another for applying a milling force. The loose roller may be mounted so as to pivot about a pivot axis in a manner of a one-sided lever such that the relative position of the loose roller relative to the fixed roller can be defined by said pivot movement. The one-sided lever may be formed between the pivot axis and the force application point.

Claims

1.-15. (canceled)

16. A roller press apparatus configured as a roller mill for grinding feedstock, comprising: a fixedly mounted fixed roller with an at least approximately positionally fixedly mounted roller axis; a floating roller mounted in a floating manner with a positionally variable roller axis that is positionally variably arrangeable relative to the fixed roller; a frame on which the fixed roller is mounted; a force action unit configured to act on the floating roller at a force action point; wherein by way of the force action unit, the fixed and floating rollers are mountable and positionable relative to one another for applying a grinding force and making mutual contact at a roller contact point or defining a grinding gap for the feedstock, wherein the floating roller is mounted so that the floating roller is pivotable about a pivot axis in a manner of a one-sided lever such that a relative position of the floating roller relative to the fixed roller is definable by a pivoting movement, wherein the one-sided lever is disposed between the pivot axis and the force action point; wherein the pivot axis is arranged on a tangent of the fixed roller and the floating roller at the roller contact point or, in the case of a non-zero grinding gap, the pivot axis is arranged between the tangent of the fixed roller at an intersection point of a connecting line between the positionally fixedly mounted roller axis and the positionally variable roller axis and the tangent of the floating roller at the intersection point.

17. The roller press apparatus of claim 16 wherein a distance between the pivot axis and the connecting line between the positionally fixedly mounted roller axis and the positionally variable roller axis along a straight line extending at right angles to the connecting line between the positionally fixedly mounted roller axis and the positionally variable roller axis and through the pivot axis corresponds to at least 0.15 times to at most 1.0 times a sum of a radius of the fixed roller and a radius of the floating roller.

18. The roller press apparatus of claim 16 wherein a distance between the pivot axis and the force action point corresponds to 1 to 5 times a distance between the pivot axis and the connecting line between the positionally fixedly mounted roller axis and the positionally variable roller axis along a straight line extending at right angles to the connecting line and through the pivot axis.

19. The roller press apparatus of claim 16 wherein the one-sided lever comprises a straight connecting line between the force action point and the pivot axis.

20. The roller press apparatus of claim 19 wherein the positionally variable roller axis extends through the one-sided lever.

21. The roller press apparatus of claim 19 wherein the positionally variable roller axis is spaced apart from the straight connecting line by at most 0.1 times a length of the straight connecting line.

22. The roller press apparatus of claim 16 configured such that the grinding acts at the force action point at an angle of 75° to 105° relative to the connecting line between the positionally fixedly mounted roller axis and the positionally variable roller axis.

23. The roller press apparatus of claim 16 wherein the roller contact point is disposed in a section between the force action point and the pivot axis and/or is disposed at a distance from the pivot axis that is less than a length of the one-sided lever, wherein the roller contact point defines a load arm of the one-sided lever.

24. The roller press apparatus of claim 16 configured such that when the rollers make contact at the roller contact point the axes of the rollers are arranged relative to the pivot axis such that a connecting line through the roller axes and the pivot axis in a plane running orthogonally thereto forms a triangle or a triangular arrangement, with each base angle on the connecting line between the roller axes being less than 50 degrees.

25. The roller press apparatus of claim 16 wherein the floating roller is pivotably mounted and arranged such that a gravitational force acting at a center of gravity of the floating roller acts on a load arm of the one-sided lever in a direction of a return movement so as to enlarge the grinding gap.

26. The roller press apparatus of claim 16 configured such that the grinding force acts about the pivot axis by way of a plunger with a hydrostat as a tilting device.

27. A method for grinding feedstock with a roller press apparatus of claim 16, the method comprising: driving the fixedly mounted fixed roller with the at least approximately positionally fixedly mounted roller axis and the floating roller mounted in the floating manner with a positionally variable roller axis; subjecting the floating roller to a force to apply the grinding force and to position the floating roller relative to the fixed roller; and pivoting the floating roller with the positionally variable roller axis by action of force in a manner of the one-sided lever about the pivot axis, thereby defining the relative position of the floating roller relative to the fixed roller, wherein the force is made to act at the force action point of a one-sided lever, wherein in terms of lever action the force action point is spaced apart at least as far from the positionally variable roller axis as the positionally variable roller axis is from the pivot axis.

28. The method of claim 27 wherein a force acts on a force arm of the one-sided lever, wherein the floating roller is pivoted relative to the fixed roller such that the floating roller makes contact with the fixed roller in a section of the force arm and defines a load arm through the roller contact point or through the feedstock with which contact is made.

29. The method of claim 27 wherein the floating roller is positioned relative to the fixed roller exclusively by way of the pivoting movement, without translational displacement.

30. The method of claim 29 wherein the pivoting movement is initiated exclusively by a translatory actuation or action of force, without torque and without a rotational actuating movement.

31. The method of claim 27 wherein the pivoting movement is initiated exclusively by a translatory actuation or action of force, without torque and without a rotational actuating movement.

Description

DESCRIPTION OF THE FIGURES

[0145] Further features and advantages of the invention will become apparent from the description of at least one exemplary embodiment with reference to drawings, and from the drawings themselves, in which:

[0146] FIG. 1 shows a roller press arrangement according to the prior art;

[0147] FIG. 2 shows, in a partially sectional side view, a schematic illustration of a roller press apparatus according to one exemplary embodiment;

[0148] FIG. 3 shows, in a partially sectional side view, a schematic illustration of a roller press apparatus according to a further exemplary embodiment;

[0149] FIG. 4 shows, in a partially sectional side view, a schematic illustration of a roller press apparatus according to a further exemplary embodiment;

[0150] FIG. 5 shows a schematic illustration of a roller press apparatus with a triangle arrangement according to exemplary embodiments;

[0151] FIG. 6 shows a sketch with a grinding gap of 0;

[0152] FIG. 7 shows a sketch with a grinding gap of >0.

DETAILED DESCRIPTION OF THE FIGURES

[0153] For reference signs not described explicitly with respect to a single figure, reference is made to the other figures. For the purpose of easier understanding, the figures are first described together with reference to all the reference signs. Details or special features shown in the respective figures are described individually. Unless explicitly mentioned otherwise, individual features of the respective exemplary embodiments can be combined with the other exemplary embodiments.

[0154] A roller press or a roller press apparatus 10 for grinding feedstock M is arranged in/on a frame 1, 11 and comprises at least one fixed roller 2 and at least one floating roller 3. The floating roller is usually mounted in a translatory manner in at least one plain bearing 4. The frame 11 comprises, for example, a frame part 11a on the bottom side and a frame part 11b on the top side. The fixed roller is mounted in at least one (fixed) bearing 12.

[0155] According to one aspect of the present invention, a floating bearing 13 for the floating roller is configured as a pivot bearing. Furthermore, a counterbearing 14 may be provided to take up reaction forces, in particular comprising a stop against which the fixed roller can be supported with respect to reaction forces. A one-sided lever arrangement 16 can be acted upon by means of a force action unit 15, in particular having at least one hydraulic actuator (for example a plunger with a tilting device) for the purpose of pivoting the floating roller about the pivot axis. The force is introduced at the force arm 16.1 of the one-sided lever and transmitted to the fixed roller via the load arm 16.2. The load arm extends from the pivot axis in the same direction as the force arm and is formed in particular between the pivot axis and the center of gravity of the floating roller or all components that are pivoted together with the floating roller. An open-loop/closed-loop control device 20 is coupled to a measuring device 21, in particular comprising a pivot angle sensor. Individual (relative) distances and action points are explained in more detail below; for details, reference is made to the corresponding figures: [0156] d1 effective distance or lever arm between the pivot axis and the positionally variable roller axis, in particular distance orthogonally to the force direction in the x or z direction; [0157] d2 effective distance or lever arm between the positionally variable roller axis and the force action point, in particular distance in the x or z direction; [0158] d3 lateral distance between the pivot axis and the positionally variable roller axis, in particular distance in the x direction; [0159] d4 lateral distance between the pivot axis and the positionally fixed roller axis, in particular distance in the x direction; [0160] d5 distance between the pivot axis and the frame or frame part on the bottom side, in particular in the z direction; [0161] F (vector) resulting rolling force or roller contact force (grinding force) in the grinding gap or at the contact point; [0162] F1 (vector) (hydraulic) force exerted on the floating roller, in particular in the x direction; [0163] F2 (vector) (hydraulic) force exerted on the floating roller, in particular in the z direction counter to the direction of gravitational force; [0164] P1 roller contact point or (theoretical) force transmission point in the grinding gap; [0165] P2 (force) action point, in particular for hydraulic force introduced; [0166] P3 pivot point or pivot axis; [0167] X0 grinding gap, in particular yz plane through the roller contact point; [0168] y2 positionally fixed roller axis; [0169] y3 positionally variable roller axis; [0170] Z0 free space (pivoting cavity) for floating roller relative to the frame; [0171] x, y, z longitudinal, transverse and vertical axis or direction.

[0172] There now follows a specific reference to the prior art (FIG. 1) and to individual exemplary embodiments of the invention (FIGS. 2 to 5), with FIG. 5 schematically illustrating the roller arrangement or mounting according to the invention that can be implemented in all exemplary embodiments.

[0173] FIG. 1 shows a previously known roller press, in which the floating roller is mounted in a translatory manner in the frame 1 in a plain bearing at the top and bottom. A translational displacement of the floating roller with respect to the fixed roller, in particular by way of an action of force at least at two force introduction points, also results in reaction forces in the fixed bearings 12. In this example, the force is made to act at two points (above and below the center of gravity of the floating roller), in particular by means of cylinders, in particular in each case in a horizontal direction corresponding to the translational displacement direction (or in that direction in which the translational plain bearing extends). This type of action of force is caused in particular by a force progression in the frame that is as symmetrical as possible. The contact point of the rollers in the grinding gap is therefore also at least approximately in the center of the frame, at least with respect to the z direction or with respect to the two force action points illustrated (force vector arrows F1, corresponding to the force exerted on the floating roller).

[0174] FIG. 2 shows a first variant for forming a one-sided lever arrangement 16 according to the present inventive concept. At point P2, the force is made to act substantially in a horizontal direction (in particular only at a single force action point), with the load arm being approximately half as long as the force arm (d1 approximately equal to d2). The action of force pivots the floating roller. The pivot axis P3 (point of rotation for the pivoting movement) is arranged at least approximately in the grinding gap X0 (d3 approximately equal to d4), i.e. at the same x coordinate. In this case, the force can be made to act selectively at just one point or at multiple points. Expressed differently: By contrast to the structure according to FIG. 1, no symmetrical arrangement of two force action cylinders is required.

[0175] FIG. 2 also indicates the effective lever length (dashed line), in a projection orthogonal to the action of force, specifically on the one hand the force arm 16.1 (relatively narrower for illustration purposes), the length of which is defined by the position of the force action point P2, and on the other hand the load arm 16.2 (relatively wider for illustration purposes), the length of which is defined by the force transmission point P1 or by the contact point of the rollers in the grinding gap. The pivoting movement is illustrated by the back-and-forth arrow about the pivot axis P3, 13. Depending on the state of loading and the size or particle spectrum of the feedstock, a pivoting movement during operation can be more or less pronounced.

[0176] The floating roller 3 is therefore held in the frame between the points P2 and P3. Optionally, a force is transmitted between the floating roller and the frame only at these points, and indirectly also via the contact point P1.

[0177] In this respect, the at least one force action unit 15 may also be configured to actuate in both directions of action (opposite pivoting directions) (in particular both tensile and compressive forces). Optionally, there is actuation only against the fixed roller, in particular since the floating roller can advantageously be pivoted back (purely) under the effect of gravitational force. Not least, this also promotes fast, reactive and thus low-load operating behavior, even in the case of comparatively massive, heavy rollers. Not least, the way in which the force is made to act in the grinding gap can also be adapted or optimized comparatively easily, in particular depending on the feedstock. Expressed differently: By contrast to the translational mounting shown in FIG. 1, no great force is required to move the floating roller back out of the grinding gap (to the left in FIG. 1). This may also provide advantages in terms of the design of the frame and/or the selection of the drives/actuators.

[0178] A triangle of forces that is defined by the points P1, P2 and P3 can also be described using the example of FIG. 2. The respective roller axis is less significant in this context. The greater the distance P2/P3 (in particular in the z direction) is in relation to the distance P1/P3, the smaller the design of the hydraulic cylinders or force introduction actuators can be. On the other hand, in the case of a large z distance P2/P3, the load at point P3, i.e. the load acting on the pivot axis, also increases (in particular large lever force when the rollers make contact). A ratio of P2/P3 to P1/P3 of at least approximately 1 to 2 may be preferred, in particular when the number of cylinders (force action actuators) should be as low as possible (on the basis of a translational mounting: in particular should be halved). In many cases, cost aspects are also of great importance, and therefore the ratio of the distances is also optimized in cost terms. If the design costs for the mounting point P3 rise to a greater extent than the costs for the cylinders, the ratio is/will be selected to be smaller if anything, and vice versa. In this respect, the ratio may also be selected in individual cases in a range from, for example, 1:1 to 1:3, in particular 1:1.5 to 1:2.5, preferably 1:2.

[0179] FIG. 3 shows a second variant for forming a one-sided lever arrangement 16 according to the present inventive concept. At point P2, the force is made to act substantially in a vertical direction or substantially orthogonally to the reaction force F at the roller contact point (in particular also at least approximately orthogonally to a plane of extent of the bottom frame part or a stand), with the load arm 16.2 being significantly shorter than one half of the force arm 16.1 (z distance P1 to P3<x distance P2 to P3). The pivot axis P3 is arranged in the grinding gap X0 (distance d3 approximately equal to distance d4).

[0180] In this arrangement, the action of the gravitational force is especially effective. The floating roller can be mounted in a particularly reactive manner in terms of a return movement, and the pivot axis can be relieved of load at least to a certain extent with regard to the weight force of the floating roller.

[0181] From a design perspective, in the case of an arrangement according to FIG. 3, a frame section laterally to the outside of the floating roller can be given a comparatively weak configuration or can be omitted entirely. Force can be conveyed from the floating roller to the frame in particular also by means of a diagonally connecting support or similar crossmember between the floating roller and the frame, in particular by means of a frame support 11.1 or strut, in particular with a directional specification for the force flow. Such a transverse support is advantageously connected directly or indirectly to a bottom side of the frame or else directly to a stand. The conveyance of force from the floating roller to the frame can be deflected in this way, in particular with a specified direction into the stand. Effect: Force can be conveyed with very low load, and the frame can be given a correspondingly narrow configuration.

[0182] FIG. 4 shows a third variant for forming a one-sided lever arrangement 16 according to the present inventive concept. FIG. 4 illustrates multiple aspects which can each be advantageous per se, but which do not necessarily have to be implemented in combination with one another, in particular the following aspects: advantageously narrow structure; advantageous force flow path; advantageous coupling of force to a/the stand (not illustrated; below frame part 11a); synergistic support of the rollers, in particular advantageous utilization of the pivot axis 13 as common bearing axis (in particular for the purpose of compensating reaction forces).

[0183] At point P2, the force is made to act substantially in a vertical direction or at least approximately orthogonally to the reaction force at the roller contact point, with the load arm 16.2 being approximately half as long as the force arm (d1 approximately equal to d2). The pivot axis P3 is arranged in the grinding gap X0 (d3 approximately equal to d4), i.e. at the same x position below the roller contact point. A special feature to be emphasized is that the fixed roller can optionally be mounted about the same pivot axis P3 or on the same pivot axis P3 as the floating roller and is supported against the counterbearing 14 with respect to reaction forces about the pivot axis. Only the floating roller 3 is actively relatively positioned. However, the counterbearing 14 may optionally also be a fixed bearing to which the fixed roller is positionally fixedly coupled (for example bearing jewel 14 screwed to the frame). Expressed differently: As is also made clear by the term “fixed roller”, a relative movement of the fixed roller is not necessarily required, i.e. not even when the pivot axis is used as a bearing axis for the fixed roller. Rather, the design shown in FIG. 4 optionally also provides the design advantage that the pivot axis of the floating roller may also be used to mount the fixed roller, in particular with regard to compensation of forces in the x direction.

[0184] The frame 11 has only one frame part 11a arranged on the bottom side. It can advantageously be coupled directly to a stand (not illustrated), thereby promoting advantageous conveyance of force, in particular in the case of very massive, large roller apparatuses. In particular, there is no need for weight-force components or reaction forces caused by the grinding operation to be introduced laterally into the side of a frame. It can in particular also be seen from FIG. 4 that a configuration of the frame 11 without a frame part on the top side provides further advantages, for example in terms of general accessibility and/or in terms of the material feed M.

[0185] FIG. 5 describes, in general with reference to all the exemplary embodiments according to the invention that are described above, a relative arrangement of the axes (pivot axis and roller axes) relative to one another in a triangle arrangement (with the triangular geometry of a triangle standing on its apex), with a purely geometrically illustrative dashed line indicating the arrangement of the roller axes y2, y3, which is symmetrical in relation to the pivot axis 13. An at least approximately isosceles triangle TR is defined by the respective axis y2, y3, 13 as corner points, with the base angle α advantageously being as small as possible. The isosceles triangle arrangement TR is produced in particular when the rollers make direct contact (grinding gap at least approximately zero or non-existent). If the rollers are spaced apart relative to one another, for example owing to feedstock in the grinding gap, the base angle will be correspondingly smaller.

[0186] In an arrangement according to FIG. 4, the base angle α of the triangle arrangement TR is still comparatively large, in particular in the region of 45°; in the case of an arrangement according to FIG. 2 or FIG. 3 (pivot axis comparatively close to roller contact point P1 in the z direction), the base angle α is comparatively small, in particular in the range of only approximately 25° to 35°. Expressed differently: the pivot axis is advantageously arranged at a (z) distance from the roller axes that is less than half of the roller diameter. Depending on the configuration of the frame and the mounting, the base angle α may assume a magnitude in the range of 20 to 50 degrees, for example (or even up to 60 degrees in an individual case).

[0187] It has been shown that, by means of such a triangle arrangement TR, a great number of the advantages of the invention can be generally ensured in each of the different exemplary embodiments, irrespective of the specific usage situation. The design concept according to the invention can therefore advantageously specifically also be realized by such triangle arrangements TR, in particular with the magnitude of the base angle or with the relative arrangement of the pivot axis in each case being a design parameter. As explained above, the relative x position and/or relative z position of the pivot axis can also be adapted individually, for example slightly relatively offset toward the axis of rotation of the floating roller and displaced out of the grinding gap. The triangle arrangement TR is preferably an isosceles triangle arrangement. However, the triangle arrangement TR is not necessarily exclusively only an isosceles triangle arrangement; rather, it is within the scope of expert adaptation in the art to optimize the two base angles at least within a narrow range of variation for the respective usage situation.

[0188] FIGS. 2 to 5 schematically indicate the one-sided lever (one-sided lever arrangement) 16 by way of a dashed line, which extends from the pivot axis 13 to the/to a force action point P2. The respective effective lever length (FIG. 2) is to be dimensioned in absolute terms, in particular orthogonally to the force direction. The illustration based on a dashed line was therefore selected by the applicant because the section in which the one-sided lever is formed can be defined individually depending on the specific selectable position for the force action point, as can the length of the lever, and also the length ratio between force arm and load arm. Irrespective of this, the floating roller is arranged both in the region of the load arm and in the region of the force arm, or these regions overlap (one-sided lever arrangement without a free load arm, i.e. without a rocker).

[0189] FIG. 6 shows, in a highly simplified manner, only the fixed roller 2 and the floating roller 3 in relation to the pivot axis P3. A connecting line is depicted between the positionally fixedly mounted roller axis y2 and the positionally variably arrangeable roller axis y3. This connecting line intersects the fixed roller 2 and the floating roller 3 at the roller contact point P1. The tangent of the fixed roller 2 and the floating roller 2 is perpendicular to this connecting line and runs through the pivot axis P3.

[0190] FIG. 7 shows a very extremely oversized grinding gap X0. In reality, the grinding gap X0 will be much smaller than the radius of the fixed roller 2 and the radius of the floating roller 3. The distance between the fixed roller 2 and the floating roller 3 now results in two spaced-apart tangents. In the example shown, the pivot axis P3 is arranged exactly centrally between the tangents.

LIST OF REFERENCE SIGNS

[0191] 1 Frame [0192] 2 Fixed roller [0193] 3 Floating roller [0194] 4 Plain bearing [0195] 10 Roller press apparatus [0196] 11 Frame [0197] 11a Frame part on the bottom side [0198] 11b Frame part on the top side [0199] 11.1 Frame support or strut, in particular with directional specification for force flow [0200] 12 (Fixed) bearing for fixed roller [0201] 13 Floating bearing for floating roller, in particular pivot bearing [0202] 14 Counterbearing for reaction forces [0203] 15 Force action unit, in particular hydraulic actuator, in particular plunger with tilting device [0204] 16 One-sided lever or one-sided lever arrangement [0205] 16.1 Force arm [0206] 16.2 Load arm [0207] 20 Open-loop/closed-loop control device [0208] 21 Measuring device, in particular with pivot angle sensor [0209] d1 Effective distance or lever arm between pivot axis and positionally variable roller axis, in particular distance orthogonal to the force direction in the x or z direction [0210] d2 Effective distance or lever arm between positionally variable roller axis and force action point, in particular distance in the x or z direction [0211] d3 Lateral distance between the pivot axis and the positionally variable roller axis, in particular distance in the x direction [0212] d4 Lateral distance between the pivot axis and the positionally fixed roller axis, in particular distance in the x direction [0213] d5 Distance between pivot axis and frame or frame part on the bottom side, in particular in the z direction [0214] F Resulting rolling force or roller contact force (grinding force) in the grinding gap or at the contact point [0215] F1 (hydraulic) force exerted on the floating roller, in particular in the x direction [0216] F2 (hydraulic) force exerted on the floating roller, in particular in the z direction [0217] M Feedstock [0218] P1 Roller contact point or (theoretical) force transmission point in the grinding gap [0219] P2 (Force) action point, in particular for hydraulic force introduced [0220] P3 Pivot point or pivot axis [0221] TR Isosceles triangle [0222] α Base angle [0223] β Alignment of the one-sided lever relative to the horizontal plane [0224] X0 Grinding gap, in particular yz plane through the roller contact point [0225] y2 Positionally fixed roller axis [0226] y2 Positionally variable roller axis [0227] Z0 Free space (pivoting cavity) for floating roller relative to the frame [0228] x, y, z Longitudinal, transverse and vertical axis or direction