Title of Invention	"ROLLER MILL"
Abstract	The invention concerns a roller mill for the milling of grain, etc. with an overdrive by means of belts (9) in order to achieve different speeds. The task in this consists in achieving even tensioning of belts (9) and consequently an even operation of the belts (9) . This task is solved in that a pulley (18) of a tension roller (8) is provided with adjustable sections (14, 15) .

Full Text

ROLLER MILL The invention concerns a roller mill for the milling of grain etc. into flour, semolina, powder, etc. It is particularly directed at the overdrive of that type of roller mill with at least one pair of rollers with fluted or smooth rollers. Roller mills for the milling of grain mostly include two or four pairs of rollers such as for instance described in DE-C-2730166 or in EP-B-334919. The rollers of a pair of rollers rotate in opposite directions and at different speeds in order to accomplish the reduction and grinding of grain grains. The roller gap is typically variable. Generally the faster running roller is driven and is connected with the slower running roller by means of an overdrive. Such an overdrive is preferably designed by means of a gear drive but which requires lubrication, develops a high noise level and requires interchangeable gears to suit very different milling conditions. Attempts have therefore been made for a long time to overcome the disadvantages of the gearing by using smooth or profiled belts. In addition to solutions with V-belts, such were especially developed with two-sided toothed profile (e.g. according to USPS 3338107) or multiple V-belt (e.g. TIMING-VEE). DEAS 1107033 for instance describes a combined V and toothed » belt with a toothed and a V-shaped side to the belt which runs between three toothed belt pulleys and which additionally drives an outer V-belt pulley. A similar solution is described by DE-A-3304832 for a roller mill. A double-sided toothed belt runs around belt pulleys of the rollers and additionally runs around a toothed belt pulley of the drive and a loose pulley. Another toothed belt overdrive is also known using V-toothed belts according to ITPS 1198054 and EP-B-425626 is also known. The latter describes a roller mill with at least one pair of rollers, wherein the shaft of the slower running roller carries a pulley which is provided with teeth with grooves parallel to the axis and includes a drive facility which is kept under tension by a third drive pulley, the position of which is adjustable. The adjustability of the entire disk is accomplished by adjusting screws or eccentric cam. The faster running roller is also provided with a pulley having teeth with grooves but which are arranged at right angles to the shaft axis. The drive facility itself is a belt profiled on the outside and inside which engages as a fit in the profiles of the aforementioned three pulleys, that is with a tooth or V-profile. In order to transmit greater forces the pulleys have been designed with a width generally accommodating three belts in parallel. These are jointly tensioned according to the aforementioned state-of-the-art and wear unevenly. Even tensioning is very difficult and not completely possible. Even prior selection and measuring is unable to solve the problems. The invention therefore is based on the task of largely avoiding the shown disadvantages of the state-of-the-art and to achieve even tensioning of the individual belts and consequently also even wear. Investigations by the applicant have shown that due to the unavoidable elastic deformations of the milling rollers in the operating condition the inner belt or inner part of the belt is subject to wear first. As a consequence any selection or measuring of belts is of no consequence, at least partly. It' is rather important to observe these different wear conditions. According to the invention a belt pulley (tension roller) is therefore of a divided design in order , to be able to individually tension the belts. This belt pulley is preferably partly divided in two. Further investigations of the applicant have shown that the assumed maximum transmission forces are not achieved in practice and in normal cases it does not therefore appear necessary to use three or more belts. This facilitates the adjusting process at the same time. The present invention relates to a roller mill for the milling of grain etc. into flour, semolina, powder, and the like with pairs of rollers mounted in a casing which among other things are connected with feed and discharge facilities for the milled goods and facilities for the adjustment of the roller gap, and the like wherein the faster turning roller of a pair of rollers is directly driven and the slower roller is forced by means of an overdrive, especially by means of belts to run with a differentiated speed and wherein this overdrive additionally incorporates a deflection or tension roller with a pulley, to run[s] the said belt(s) around said pulleys completely and a pulley partly and with the opposite side and that furthermore the pulley is adjustable, characterized in that the pulley is provided with two sections which are provided with means for the separate adjustment/tensioning of the sections. The invention is described in more detail in the following in an example of the design by means of a drawing. In the drawing it shows Figure 1: A schematic representation of a roller overdrive Figure 2: The overdrive in the roller package Figure 3: A representation of the tension roller (partial section) A 4-roller mill 1 with a casing 2, such as described for instance in DE-D-2730166, contains, besides the not explicitly represented feed and discharge facilities for the grinding goods, among other things, two pairs of horizontally mounted rollers 3, 3', 4, 4', which at their ends are provided with pulleys 5, 6. The roller gap of a roller pair 3, 4 or 3', 4' can be changed by means of a motor or manual adjustment 7. Additionally provided is a deflection or tension roller 8 with a pulley 18. Two commercially available belts 9 profiled on both sides run around the pulleys 5, 6 and 18. Preferably the belts 9 have an inside with a multiple V-profile in longitudinal direction and a toothed profile across the longitudinal direction on the outside. In addition the pulley 18 of the tension roller 8 is provide with separately adjustable sections 14, 15 wherein the inner section 14 and the outer section 15 can be adjusted with a screw 13 and an eccentric cam 19 respectively. The eccentric cam 19 is fixed with a nut 17. A screw 16 secures a shaft. It is therefore possible to optimise the tension for each belt 9 in order to achieve an even overdrive or torque transmission and also an even type of wear. The sections 14, 15 are preferably supported by antifriction bearings 20. The use of two belts 9 permits a good adaptation to all operating conditions. The rollers of a pair 3, 4 or 3', 4' are arranged in a so-called roller package as described in DE-C-2730166. The rollers are mounted in bearing bodies 10, 10', while the bearing body 10' is connected with a frame carrier 11. This roller package is mounted on a base not shown in detail of casing 2. The milling gap adjusting device 12 is simultaneously designed as foreign body or overload protection. With such a roller mill 1, which is mainly employed in lour milling, the rollers of a pair run with different speeds and a specific roller gap against one another. In this way it is possible to exert not only pressure but also a friction and shearing effect on the goods to be milled. A'main drive which is not shown on one side of the roller mill 1 drives one of the two rollers of the pair directly, generally the faster roller 4, 4'. The slower roller 3, 3' is dragged along by the faster roller 4, 4' during the milling process by way of the product. In order to permit various speeds an overdrive (belt 9) with different pulley diameters is used. Since the rollers of the pair rotate in opposing directions of rotation, the pulley 5 must be arranged outside belt(s) 9. Because of the adjustable roller gap (and consequently also the distance of the roller axes) a tension roller 8 must be provided. Accordingly, the pulley 5 is provided with a toothed profile parallel to the axis of the roller 3 (3'). The pulleys 6 and 18 on the other hand have a flat profile or a V-groove profile in circumferential direction or a tooth profile at right angles to the axis of the roller 4 (4' ) . Pulley and belt profiles are matched to one another. A positive connection exists between pulley 5 and belt 9 and a friction or non-positive connection between belts 9 and pulley 6 or 18. Such an arrangement can be transferred analoguously to the other pair of rollers and even to an 8-roller mill according to EP-B-334919. The invention is not limited to the shown embodiment. ABBREVIATIONS 1 Roller mill 2 Casing 3 Roller 3' Roller 4 Roller 4' Roller 5 Pulley 6 Pulley 7 Manual adjustment 8 Tension roller 9 Belt 10 Bearing body 10' Bearing body 11 Frame carrier 12 Milling gap adjustment 13 Screw 14 Section 15 Section 16 Screw 17 Nut 18 Pulley 19 Eccentric cam 20 Anti-friction bearing We Claim: 1. A roller mill for the milling of grain etc. into flour, semolina, powder, and the like with pairs of rollers (3, 4; 3' 4s) mounted in a casing (2) which among other things are connected with feed and discharge facilities for the milled goods and facilities for the adjustment of the roller gap, and the like wherein the faster turning roller (4 and 4') of a pair of rollers is directly driven and the slower roller (3, 3') is forced by means of an overdrive, especially by means of belts (9) to run with a differentiated speed and wherein this overdrive additionally incorporates a deflection or tension roller (8) with a pulley (18), to run[s] the said belt(s) (9) around said pulleys (18, 6) completely and a pulley (5) partly and with the opposite side and that furthermore the pulley (18) is adjustable, characterized in that the pulley (18) is provided with two sections (14, 15) which are provided with means (13, 17, 19) for the separate adjustment/tensioning of the sections (14, 15). 2. A roller mill as claimed in claim 1, wherein the roller mill (1) is a 4 or 8 - roller mill. 3. A roller mill as claimed in claim 1 wherein the outer section (15) is adjustable by means of an eccentric cam (19). 4. A roller mill substantially as herein described with reference to and as illustrated in the accompanying drawings.

Documents:

3059-del-1998-abstract.pdf

3059-del-1998-claims.pdf

3059-del-1998-correspondence-others.pdf

3059-del-1998-correspondence-po.pdf

3059-del-1998-description (complete).pdf

3059-del-1998-drawings.pdf

3059-del-1998-form-1.pdf

3059-del-1998-form-13.pdf

3059-del-1998-form-19.pdf

3059-del-1998-form-2.pdf

3059-del-1998-form-3.pdf

3059-del-1998-form-4.pdf

3059-del-1998-form-6.pdf

3059-del-1998-gpa.pdf

3059-del-1998-petition-137.pdf

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