阅读说明：本技术 带有刮刀的辊磨机 (Roller mill with scraper ) 是由 D·里肯巴赫 D·马克 P·霍伦施泰因 于 2019-05-27 设计创作，主要内容包括：本发明涉及辊磨机(1),其包括壳体(2),所述壳体具有碾磨物料入口(3)、至少一个碾磨物料出口(4)和至少两个弧形辊(5,5′),所述弧形辊分别可绕辊轴线(6)旋转地布置在所述壳体(2)内,其中至少一个辊(5)配属有刮刀(7)。根据本发明,所述刮刀(7)具有刀片(8),所述刀片用于通过在所述刀片(8)的整个长度(L)上延伸的刮刀刃(10)从辊面(9)上刮掉碾磨物料。该辊磨机还包括带有容置区(12)的支座(11)。所述支座可绕平行于所述辊轴线的轴线(13)倾转地布置在所述壳体(2)内,在所述刀片(8)和所述容置区(12)之间设置有弹性支承件(14)。(The invention relates to a roller mill (1) comprising a housing (2) having a grinding stock inlet (3), at least one grinding stock outlet (4) and at least two curved rollers (5, 5') which are each arranged in the housing (2) so as to be rotatable about a roller axis (6), wherein a scraper (7) is associated with at least one roller (5). According to the invention, the scraper (7) has a blade (8) for scraping grinding stock off the roll surface (9) by means of a scraper edge (10) extending over the entire length (L) of the blade (8). The roller mill also comprises a support (11) with a receiving area (12). The mounting is arranged in the housing (2) so as to be tiltable about an axis (13) parallel to the roller axis, and an elastic bearing (14) is arranged between the blade (8) and the receiving region (12).)

1. A roller mill (1) comprises a housing (2) having a grinding stock inlet (3), at least one grinding stock outlet (4) and at least two curved rollers (5, 5') which are each arranged rotatably about a roller axis (6) in the housing (2), wherein a scraper (7) is associated with at least one roller (5), wherein the scraper (7)

-having a blade (8) for scraping off grinding stock from a roll surface (9) by means of a scraper edge (10) extending over the entire length (L) of the blade (8), and

-comprising a seat (11) with a housing area (12), wherein the seat is tiltably arranged in the housing (2) about an axis (13) parallel to the roller axis,

characterized in that an elastic support element (14) is arranged between the blade (8) and the receiving region (12).

2. A roller mill (1) according to claim 1, characterized in that the receiving area (12) is in the form of a groove (15), wherein the resilient support member (14) is arranged at least between the groove wall (16) and the blade (8).

3. A roller mill (1) according to claim 2, characterized in that a resilient support member (14) is arranged between the blade (8) and the two groove walls (16, 16').

4. A roller mill (1) according to claim 2 or 3, characterized in that the blade (8) abuts against the groove bottom (17).

5. A roller mill (1) according to any of the preceding claims, characterized in that the blades (8) and the resilient support members (14) are held in a clamping profile (18) arranged in the receiving area (12).

6. A roller mill according to any preceding claim characterized in that the ratio of the length (L) to the width (B) of the blade (8) is 1.6: 1 to 300: 1.

7. A roller mill (1) according to any of the preceding claims, characterized in that the ratio of the height (H) of the blade to the Free Height (FH) is more than 1: 1 to 6: 1.

8. A roller mill (1) according to any of the preceding claims, characterized in that the blades (8) are arranged at an angle (a) of 20 ° to 75 °, preferably 30 ° to 60 °, particularly preferred 30 ° to 50 ° relative to the roller surface (9).

9. A roller mill (1) according to any of the preceding claims, characterized in that the resilient support members (14) are formed as resilient strips having a shore hardness of 15 to 100, preferably 30 to 90, especially preferably 40-80.

10. A roller mill (1) according to any of the preceding claims, characterized in that the carrier is provided with a counterweight (19) by means of which the blade (8) can be tilted about the axis (13) and pressed against the roller surface (9).

11. A roller mill (1) according to any of the preceding claims, characterized in that the scraper (7) is operatively connected with lifting means by means of which the blade (8) can be tilted about the axis (13) and removed from the roll surface (9).

12. A roller mill (1) according to any of the preceding claims, characterized in that the blade (8) is arranged with the scraper edge (10) parallel to the roller axis (6) when the blade (8) is not in contact with the roller surface.

13. A roller mill (1) according to any of the preceding claims, characterized in that the blade (8) is accommodated in the accommodation zone (12) over its entire length (L).

Technical Field

The invention relates to a roller mill with scrapers according to the independent claim.

Background

Curved rollers are used in roller mills to counteract the curvature of the rollers during operation, which is caused by the high contact pressure generated during the grinding of the grinding stock. This ensures that the grinding gap has a uniform grinding gap width during operation. A scraper is arranged directly downstream of the grinding gap for scraping off the grinding stock.

The doctor blade is intended to ensure that the grinding stock does not adhere to the roller, and therefore such adhesion of the grinding stock is undesirable in many respects. On the one hand, the adhesion of the grinding stock to the rollers on renewed passage can cause the grinding gap to narrow, which can lead to undesirable oscillations and vibrations. On the other hand, when passing through the grinding gap again, the adhered grinding stock is further compressed and compacted, making it more difficult to remove the grinding stock adhering to the roller with a scraper. This can be adversely affected by the high temperatures generated during the milling process, which can cause the milled material to dry out and "cake". In addition, the adhering grinding stock provides a better adhesion surface for the other grinding stock and promotes an increase in this grinding stock deposit. In the worst case, the rolls must be stopped and the scale manually removed in a laborious manner.

Heretofore, doctor blades have been employed which have a blade with a doctor edge which is rectilinear in the unused state or in the undeformed state and is held firmly in a holder. The support is pivotably arranged below the roller, directly downstream of the roller gap, which is pressed against the roller during operation by means of a counterweight, which is fastened to an extension arm of the support.

The blade is aligned with the fixed roller and the support is then bent in an intermediate position (which corresponds to the intermediate position of the roller) by means of a pulling device (which generally acts as an extension arm of the counterweight) to compensate for the camber of the roller. Such a doctor blade is shown for example in EP0040432a 1.

This solution is not satisfactory because the compensation takes place while the roll is fixed, but the roll is bent during operation and the camber varies accordingly. While the originally straight blade may be sharpened to counteract the crowning of the roll, there are other causes of non-contact between the doctor blade and the roll. For example, deformation and thermal expansion during operation are not constant. In the prior art, the contact pressure of the doctor blade used is too high compared to the contact pressure actually required for effective cleaning (in order to deform the doctor blade so that it can adequately conform to the roll surface). This relatively high contact pressure results in unnecessarily severe wear of the doctor blade and the roll surface.

Disclosure of Invention

It is therefore an object of the present invention to provide a roller mill with at least one scraper which avoids the disadvantages of the known methods and allows optimum conformity to the camber of the roller during operation, in particular while complying with safety regulations and maintaining low wear.

This object is achieved by a roller mill according to independent claim 1.

The roller mill comprises a housing having a grinding stock inlet, at least one grinding stock outlet and at least two curved rollers, which are each arranged rotatably about a roller axis in the housing.

At least one roll is assigned a doctor blade. The rolls of the roll mill, preferably all rolls, are provided with scrapers. A plurality of doctor blades can also be associated with a roll.

According to the invention, the scraper comprises a blade for scraping off material to be ground from the roll surface. The blade has a scraping edge extending over its entire length. The blade length preferably corresponds substantially to the axial length of the roll, so that the doctor blade can be used to scrape the entire roll surface. Segmented blades consisting of multiple elements are also contemplated which, when aligned, can continuously scrape the entire roll surface.

The doctor blade also comprises a holder with a receiving area, wherein the holder is arranged in the housing tiltably about an axis parallel to the roller axis. The holder and thus the blade can thus be removed from the roll surface, for example by tilting, when no grinding operation is carried out, in order to protect the blade and the roll surface.

According to the invention, the elastic support is arranged between the blade and the housing zone.

By means of the resilient support in the receiving region of the blade, it is ensured that the blade is not clamped firmly in the holder, but rather is allowed to move relative to the holder. In particular, when the blade contacts the roll surface, the blade bends and conforms closely to the roll surface, thereby compensating for bowing, bending, or thermal expansion of the roll that can occur during operation. It will be understood that the resilient support is arranged on the side of the blade that is subjected to pressure when the blade contacts the roller surface during operation of the roller mill, i.e. away from the roller. The blades may be designed to be able to bend to conform to the roll face, but for other bending moments, particularly those parallel to the roll axis, the blades are flexurally rigid, thereby avoiding blade chatter during operation. The carrier is preferably arranged on the roller mill such that its axis remains parallel to the roller axis during a movement (e.g. offset displacement) of the roller axis.

The receiving region is preferably designed as a recess, the resilient support being arranged at least between the recess wall and the blade.

The thickness of the support (on one or both sides of the blade) is typically 2 to 10 millimeters (mm) within the scope of the invention.

In the sense of the present invention, a groove wall refers to a wall of the groove which extends in its depth direction. In the sense of the present invention, a groove bottom refers to the wall of the groove remote from its open side, which corresponds to the lateral surface of the support.

The groove is preferably formed here as a groove having two mutually parallel groove walls and a flat groove bottom, wherein the groove bottom is arranged perpendicular to the groove walls.

Preferably, the resilient support is arranged between the blade and the two recess walls.

This embodiment allows the blade to bend on both sides, so that in order to allow the same degree of freedom as in the above described embodiment using only one resilient support, two resilient supports of halved thickness have to be arranged on both sides of the blade.

The insert preferably abuts the bottom of the groove.

This ensures that blade slipping due to the contact pressure of the blade with the roll surface is avoided, since the blade, unlike the doctor blades according to the prior art, is not rigidly connected to the holder.

The blade and the at least one elastic support are preferably held in a clamping profile which is arranged in the receiving region.

In order to simplify assembly, it can be provided that the blade and the at least one elastic support can be held in the clamping profile. The clamping profile is then inserted into the receiving region and held in place by a holding tool.

In a corresponding manner to the embodiments described above with respect to the configuration of the blade and of the at least one elastic holder in the groove, the clamping profile can be configured such that the elastic support is mounted on one profile wall (which corresponds to the groove wall) or on both profile walls. For example, the blade may be placed on the bottom of the profile (corresponding to the bottom of the groove) to prevent it from sliding.

Preferably, the blade and/or the abutment and/or the clamping profile comprise a transverse stop mechanism which prevents displacement of the blade in an axial direction with respect to the roller axis.

The blade is preferably in the form of a flat profile, in particular a flat profile with a rectangular cross section. The blade is preferably made of cold rolled steel strip (e.g. in steel WB, chromium and nickel free, hardened, tempered and ground). It is particularly preferred that the tensile strength of the blade is in the range of 1550-.

The thickness of the blade is typically 0.5-2mm within the scope of the invention.

The length to width ratio of the blades is preferably from 1.6: 1 to 300: 1.

In the sense of the present invention, blade length means the spatial extent of the blade in the direction of extension of the doctor edge. The length of the blade may be from 100mm to 3000mm, preferably from 500mm to 2500mm, particularly preferably from 1000mm to 2000mm, for example 1500 mm.

In the sense of the present invention, blade width means the spatial extension perpendicular to the blade length. The blade width may be from 10mm to 60mm, preferably from 20mm to 55mm, particularly preferably from 30mm to 50mm, such as 40 mm.

Thus, in the sense of the present invention, blade height thus refers to the spatial extent of the blade perpendicular to the blade length and the blade width, which extends from the doctor edge to the end facing away from the doctor edge. Typically, within the scope of the invention, a total blade height of 10-30mm is accommodated in the resilient support.

The ratio of the height of the blade to the free height is preferably 6: 1, more preferably greater than 1: 1 to 6: 1.

In the sense of the present invention, the free height of the blade means the height dimension of the blade projecting from the doctor edge. Since the blade does not contact the holder, the free height is understood to mean the height dimension between the doctor edge and the (imaginary) envelope surface of the holder.

The blade is preferably arranged at 20 ° to 75 °, more preferably 30 ° to 60 °, particularly preferably 30 ° to 50 °, relative to the roll surface when it contacts the roll surface.

The angle is measured as the angle between a plane tangent to the roll surface and the height direction of extension of the blade.

Since the roller is curved, according to the present invention, the blade is bent when it contacts the roller, and thus the angle is slightly changed over the entire length of the blade, and thus the angle of the center of the roller (in which the camber of the roller is the largest) is used as a reference angle.

The elastic support may be made of or comprise an elastic material, preferably selected from: natural Rubber (NR); styrene-butadiene rubber (SBR); butyl rubber (IIR); ethylene propylene rubber (EPDM); nitrile Butadiene Rubber (NBR); neoprene rubber (CR); chlorosulfonated polyethylene synthetic rubber (CSM); polyurethane rubber (australia, european union); silicone rubber ((M) Q); polyacrylate elastomers (ACM); hydrogenated nitrile rubber (H-NBR); fluororubbers (FPM); polyurethane (PU). Ethylene-propylene rubber (EPDM) and silicone rubber ((M) Q) are particularly preferred.

In the simplest case, the elastic support is designed as an elastic strip. The support member, and in particular the resilient strip, may be formed continuously or intermittently over the length of the blade. The intermittent formation of the support member is particularly feasible for individually adjusting the stiffness of the resulting overall support member. For example, the harder material can be arranged in an intermittent manner to obtain a hardness of the entire bearing corresponding to a continuous bearing made of the softer material.

The elastic material of the support member, in particular of the elastic strip, has a shore hardness of 15 to 100, preferably a shore hardness of 30-90, particularly preferably a shore hardness of 40 to 80 (according to ASTM D2240; and/or a shore hardness a of 5 to 30 (measured according to DIN ISO 7619-1)).

The resilient support may have a density of 0.25g/cm³To 0.85g/cm³Preferably 0.35g/cm³To 0.75g/cm³Particularly preferably 0.45g/cm³To 0.65g/cm³(according to DIN 53479A).

This embodiment is a very simple and low cost variant. In addition, the strip may be replaced and its stiffness adjusted depending on the application.

The support is preferably provided with a counterweight by means of which the blade can be tilted about an axis and pressed against the roll surface.

Thereby, the contact pressure of the blade with the roller can be adjusted in a simple manner, i.e. by changing the weight and/or length of the lever arm.

The doctor blade is preferably operatively coupled to a lifting device by means of which the blade can be tilted about an axis and removed from the roll surface.

This embodiment allows the blade to be removed from the roll face when no milling operation is performed and in particular to be connected to the actuating mechanism of the roll so that when the roll is moved in and/or out, the blade also comes into contact with the blade surface and/or is removed therefrom.

The blade is preferably arranged such that the doctor edge is parallel to the roll axis when the blade is not in contact with the roll surface.

The blade is preferably accommodated in the accommodation region over its entire length. The resilient support is ultimately formed over the entire length of the blade.

Alternatively, the blade may be accommodated within the accommodation region only in certain portions and/or the resilient support may be formed over the length of the blade only in certain portions. It will be appreciated that in this case, in the region where there is no resilient support, when the blade is not in contact with the roller surface, then the blade must similarly not contact the receiving zone.

Drawings

The invention will be described in more detail below on the basis of preferred embodiments and with reference to the attached drawing figures, in which:

fig. 1 is a schematic sectional view of a roller mill according to the invention;

fig. 2 is a schematic cross-sectional view of a doctor blade according to a first preferred embodiment of the invention; and

fig. 3 is a schematic cross-sectional view of a doctor blade according to a second preferred embodiment of the invention.

Detailed Description

Fig. 1 schematically shows a roller mill 1 according to the invention. The roller mill 1 comprises a housing 2 with a ground material inlet indicated by arrow 3 and a ground material outlet 4 indicated by arrow 4. Arranged in the housing 2 are two curved rollers 5 and 5 ', which are each mounted rotatably about a roller axis 6 or 6' and are driven in opposite directions by means of a drive mechanism, not shown. The directions of rotation of the rollers 5 and 5' are indicated by arrows, respectively.

Directly downstream of the grinding gap 20, a doctor 7 or 7 'is associated with each roller 5 or 5', respectively. The doctor 7 of the roll 5 is shown separately in fig. 2 and 3 in two possible variants.

The doctor 7 of fig. 2 and 3 comprises a blade 8 formed from a flat metal profile having a length L, a width B and a height H. The longitudinal direction of the blade 8 is indicated by a vector L.

In fig. 2 and 3, the blade 8 contacts the roll surface 9 with a sharp doctor edge 10. The blade 8 is arranged so that the plane TE (which is tangent to the roll surface 9 at the point of contact of the blade 8) and the blade 8 are inclined at an angle a.

In the embodiment of fig. 2 and 3, the doctor 7 has a mount 11 which is arranged tiltable about an axis 13. This axis 13 extends parallel to the roller axis 6 or 6 'and remains parallel to the roller axis 6 or 6', even if the roller axis is offset, for example in the case of an offset roller.

In the embodiment of fig. 2, the holder 11 comprises a receiving region 12, which is realized here by a recess 15 having two recess walls 16 and 16' extending parallel to each other and a recess bottom 17 extending perpendicular to the recess walls, which extends in the longitudinal direction L of the blade 8 (and thus of the holder 11). The blade 8 is arranged in the groove 15 and contacts the groove bottom 17 by the end facing away from the doctor edge. The elastic strips 14 are arranged on both sides of the blade 8 between the respective groove wall 16 or 16' and the blade 8, so that the blade 8 has a certain freedom of movement in the groove 15 and can be bent and can conform to the curvature of the roll 5, in particular by a bending moment parallel to the height of the blade 8.

FH indicates the free height of the blade 8, which corresponds to the height at which the blade 8 is not arranged between the elastic strips 14.

In order that the blade 8 can be pressed against the roll surface 9, the abutment 11 is arranged tiltable about the axis 13 as already explained above. In addition, the support comprises a counterweight 19, which by means of leverage effects the tilting of the support 11 and presses the blade 8 against the roll surface 9.

The doctor 7 shown in fig. 3 corresponds substantially in design to the doctor 7 of fig. 2, whereby the blade 8 and the elastic strip 14 are arranged in a clamping profile 18, wherein the clamping profile 18 is inserted into the receiving region 12 of the holder 11.

The clamping profile 18 is designed as a plastic profile and has two profile walls 160 and 160 'extending parallel to one another and a profile bottom 170 extending perpendicular to the profile walls, which correspond functionally to the groove wall 16 or 16' and the groove bottom 17.

The clamping profile 18 makes it possible to easily arrange the blade 8 into the housing zone 12 by means of the elastic strip 14.