GB2042312A - Ground rollers - Google Patents

Abstract

A ground roller has outwardly projecting extensions arranged in annular groups. Scrapers engage in the spaces between these groups and obtend an acute angle with the roller surface, whereby their lower scraper edge is located at least 1/5 of the radius of the roller lower than the axis of rotation of the ground roller. The scrapers, moreover, are arranged on holders which at right angles to the direction of travel have a substantially lesser dimension than the spaces between the groups of extensions and are mounted on a crossbeam located over the ground roller. In a preferred embodiment, moreover, the slots between adjacent scrapers are enlarged in the direction towards their rear end. <IMAGE>

Description

SPECIFICATION Ground rolls The invention relates to ground rolls or a ground roll having an endless, rotationally symmetrical roll jacket which is provided with outwardly projecting extensions arranged in annular groups, whereby spaces are formed between the individual groups and in these spaces scrapers are provided engaging from behind and which are detachably and fixedly connected to a crossbeam located above the circular paths described by the extensions and obtend an acute angle of adjustable size with a tangential plane laid along the roll jacket.

Such ground rolls are already known from German OS 24 38 374. In such ground roll the crossbeam is hood-shaped and has a dimension in the direction of travel which substantially corresponds to the diameter of the circular paths of the extensions and encloses these in its upper region. Furthermore, the scrapers are longitudinally adjustable and screwed to an L-shaped strap extending over the whole extension of the crossbeam at right angles to the direction of travel; said L-shaped strap in turn being mounted on the rear portion of the crossbeam and being adjustable in the direction of travel. This not only provides a vertical adjustability of the scraper edges relative to the axis of rotation of the ground rolls, but at the same time also provides an adjustability of the angle between scrapers and the tangential plane laid along the roll jacket level with their lower scraping edge.

This kind of arrangement permits in favourable manner adaptation of the position and angle position of the scrapers to the given ground conditions prevailing and readjustment of the scrapers in a direction towards the roll jacket to compensate the unavoidable wear and tear in course of deployment of the ground rolls, at the lower scraper edges and hence to ensure a satisfactory function of the scrapers over a long overall deployment period.

Since the scrapers, however, can be downwardly adjusted only until their scraping edges are located lower than the axis of rotation of the ground rolls at a maximum by 1/6 of the radius of the roll jacket, this ground roll does not permit the achievement of satisfactory operation under all conditions.

More especially with damp and caking soil types, the particles of soil adhering to the roll are conveyed relatively far upwardly and then drop back to the ground again in batches and in clumps, so that an uneven coarse clodded ground surface is created. This disadvantage is further increased by the fact that due to the batchwise dropping of soil particles from the scrapers these particles of soil do not again drop into the recesses which were formed in the ground surface when the roll jacket picked them up.

A further more important disadvantage occurs in the known ground roll in that the slots formed between the scrapers for the passage of the extensions of the rolls are defined by the L-shaped strap at their rear region. This prevents particles of straw or other vegetation particles picked-up and carried upwards by the extensions from the ground from dropping back freely and individually onto the ground surface, and such settle on the parts of the Lstrap defining the slots. These, together with the soil dragged upwards, form large lumps which from time to time due to their weight drop back onto the ground and hence cause additional deterioration of the state of the ground surface or by the extensions of the ground roll are dragged through the slots and block-up the hood-shaped crossbeam such that the ground roll locks and is dragged in non-rotating state along the ground.Even if this disturbance requiring a time-consuming cleaning of the ground rolls does not occur, the lumps formed of vegetation residues and soil act as a brake by reason of which the traction requirement for the ground rolls is substantially increased.

Furthermore, the German OS 27 53 083 discloses a generically identical ground roll in which, however, the crossbeam for arranging the scrapers is located close to the circular paths of the extensions and the lower scraping edge of the scrapers is located lower than the axis of rotation of the ground roll by at least 1/5 of the radius of the roll jacket.

This additionally downwardly adjustable position of the scraping edge also provides a satisfactory action of the scrapers in damp and caking soils. Since these may be so adjusted that the particles of soil carried along by the roll jacket are scraped off immediately after being ripped out of the ground surface and drop back into the identations formed in the ground.

Since, however, the slots between the scrapers provided for the passage of the extensions of the roll therethrough and regardless of the fact that the scrapers are arranged on the crossbeam singly or in groups and independently of the fact that the crossbeam has a maximum width in the direction of travel which is less than the radius of the circular paths of the extensions, since these slots terminate in the central or rear region of the scrapers, this ground roll also has the disadvantage that plant particles carried along by the extensions settle on the scrapers and with the soil connected therewith form beardlike lumps or clods which render the ground surface behind the roll uneven by dropping-off in batches and considerably increase the traction power required by the ground roll.

This disadvantage is still further increased in that the soil permeated with vegetable particles due to the relatively large setting angle of the scrapers relative to the horizontal straight line drawn relative to their scraping edge, is readily pushed by the extensions along the slots to their end and settles all the firmer at these points. Even with scrapers mounted individually on the crossbeam or an L-shaped strap secured thereto, this disadvantage is not diminished, since the slots are relatively short due to the close position of the crossbeam behind the circular paths of the extensions.

The object of the invention is the improvement of the method of operation of the scrapers of such a ground roll so that satisfactory operation of the ground roll is attained in all types and conditions of soil.

According to the present invention there is provided a ground roll having an endless, rotationally symmetrical roller jacket which is provided with extensions arranged in annular grups and projecting outwardly, whereby spaces exist between the individual groups and scrapers, engaging from behind, are provided in these spaces and are detachably and securedly connected to a crossbeam located above the circular paths of the extensions, and the scrapers with their lower scraping edges obtend an actue angle of adjustable size with a tangential plane extending along the roll jacket level, characterised by the feature that the lower scraping edge of the scrapers is located lower by at least 1/5 of the radius (R) of the roll jacket than the axis of rotation of the ground roll, that for the passage of the extensions, slots are provided open at their rear end and extending between the scrapers and over their whole length (L), and that the scrapers are located each on upright holders secured to the crossbeam and are substantially narrower than the scrapers viewed at right angles to the direction of travel.

Due to these measures the soil particles carried along by the roll jacket or the extensions are scraped off at a point at which (as in the ground roll according to German OS 27 53 083) they drop back into the indentations formed in the ground so that a flat ground surface is created behind the ground roll.

Moreover, the plant particles carried along by the extensions can slide freely along the edges of the slots formed between the scrapers to their open end, from where, without being forced to conglomerate, they drop back onto the ground surface. Hence, they no longer impair the sowing during the subsequent tilling of the ground by means of seed drills. If however, plant particles, mixed with soil are still drawn through two adjacent scrapers, then within the substantially greater space between the holders and the extensions they are again loosened and drop either behind or, when carried along by the extensions for somewhat longer, drop back in front of the ground roll again onto the ground surface.

A still better scraping action may be obtained under certain conditions by the fact that the scrapers relative to a horizontal straight line drawn through their lower scraping edge obtend a setting angle of a maximum 25 . Herewith, however, the ground particles carried along by the roll jacket cannot slide along the scrapers, but fall back onto the ground directly after the scraping operation. In view of the plant particles carried along by the extensions a further improved scraping effect is obtained in that the slots between adjacent scrappers are enlarged or widened towards their rear end.

In a preferred embodiment of the invention each holder is comprised of an upper part mounted on the crossbeam and a lower part supporting the scraper, wherein the lower part is located on the upper part in an upright direction of the scrapers and arranged displaceable in a longitudinal direction on the upper part and lockable or securable in different positions. These measures permit a simple adjustment both of the vertical position of the lower scraper edge and the angular adjustment of the scrapers relative to the roll jacket and hence an accurate adaptation to the given prevailing ground conditions. Moreover, as in the above-described known ground roll, the unavoidable wear on the lower scraper edge may be taken into account, so that the same scrapers provide a very long deployment time and thus a satisfactory scraping action.

In a further development of the invention, the space between the leading edge of each holder and the roll jacket widens upwardly from the scraper, a ready disengagement of these parts is attained even when possible plant particles drawn through between the roll jacket and the lower scraper edge. If herewith the rear edge of each holder or its lower part is located at least at its lower region within the rotary paths of the extensions, then, if necessary, plant particles which are pulled through the slots between two adjacent scrapers in collaboration with the rear edge of the holder, may be scraped off the extensions.

Finally, the invention provides that the cross-beam in a manner known per se has a maximum width which is less than the radius of the rotary paths of the extensions, and that the crossbeam is located in its entity over the ground roll. Because of these measures, large open spaces are formed above the individual scrapers and in these spaces the plant particles drawn through the slots by the extensions can again expand. Futhermore, the low width of the crossbeam, clogging may be avoided in the space located beneath towards the roll jacket or to the extensions even with a considerable influx of plant particles, for example, in a ground roll mounted on a leading ground cultivating implement and a turnover of stubble or a field provided with priming.

The invention will be described further by way of example, with reference to the accompanying drawings, in which: Figure 1 is a schematic side view of a ground roll; and Figure 2 is an end view from the rear of a section of the roll of Fig. 1.

A ground roll 1 has an endless rotationally symmetrical roll jacket 2 on which outwardly projecting extensions 4 are mounted gathered in annular groups 3. Equal spacings A are provided between these annular groups 3.

A crossbeam 6 extends over the ground roll 1 and outside of the paths 5 generated by rotation of the extensions 4 indicated in the drawings by chain-dotted lines.

The crossbeam 6 seen in the direction of travel denoted by the arrow 7 has a width B which is less than the radius R of the paths 5.

Downwardly projecting plates 9 viewed in the direction of travel 7 are chamfered at both ends and are welded at the two end faces 8 of the crossbeam 6 and the ground roll is rotatably mounted in these plates 9. Holders 10 which are each comprised of an upper part 11 and a lower part 1 2 are located behind the crossbeam 6. The upper parts 11 are welded herewith in staggered formation relative to the annular groups 3 of the extensions to the crossbeam 6 and are equidistantly spaced (A) from each other as the ring-shaped groups 3.

Two upright elongate holes 1 3 are provided in each of the lower region of the upper parts 11 and bolts 1 4 project through these holes 1 3 and secure the lower parts 1 2 to the upper parts 11.

The lower parts 1 2 are each provided with an angular foot 1 5 on which, by means of a screw 17, a scraper 1 6 is mounted with spacing A and engages between two annular groups 3 of the extensions. The scrapers 1 6 each have a slot 1 8 extending in their longitudinal direction and assume such a position that their lower scraper edge 1 9 is lower by at least 1/5, (and in the position shown in the drawings, by 2/3) of the radius R of the roll jacket 2, than the axis of rotation 20 of the ground roll 1.Furthermore, the scrapers 1 6 obtend an acute angle a with a tangential plane 21 laid against the roll jacket 2 level with their lower scraping edge 1 9 whilst, relative to a straight line 22 drawn through their lower scrapping edge 19, they have a setting angle P of 1 5 (this angle not exceeding a value of 25 ).

If the angle a is to be increased, then after slackening the screws 14 and 17, the lower part 1 2 is slid upwards on the upper part 11 of the holder 10, and the scraper 1 6 on the foot 1 5 is displaced to the rear-it being necessary to note that in the required new position of the scraper 1 6 the lower scraping edge 1 9 thereof is constantly close to the roll jacket 2. A reduction of the angle a is then attained by displacement of the lower part 1 2 of the holder 10 and the scraper 1 6 in a given opposite direction.

The holders 10 are so arranged that in every position of the scrapers 1 6 the space Z between the leading edge 23 of the whole holder 10 or its upper and lower part 11, 1 2 and the roll jacket 2 is widened or enlarged upwardly. Moreover, the rear edge 24 of the holder 10 or the lower part 11 thereof is located within the circular paths 5 of the extensions 4.

Finally, for the passage of the extensions 4 between the individual scrapers 16, slots 25 are provided which are widened in a rearward direction and are also kept fully open at the rear end of the scrapers 1 6.

Claims (8)

1. A ground roll having an endless, rotationally symmetrical roller jacket which is provided with extensions arranged in annular groups and projecting outwardly, whereby spaces exist between the individual groups and scrapers, engaging from behind, are provided in these spaces and are detachably and securedly connected to a crossbeam located above the circular paths of the extensions, and the scrapers with their lower scraping edges obtend an acute angle of adjustable size with a tangential plane extending along the roll jacket level, characterised by the feature that the lower scraping edge of the scrapers is located lower by at least 1/5 of the radius (R) of the roll jacket than the axis of rotation of the ground roll, that for the passage of the extensions slots are provided open at their rear end and extending between the scrapers and over their whole length (L), and that the scrapers are located each on upright holders secured to the crossbeam and are substantially narrower than the scrapers viewed at right angles to the direction of travel.

2. A ground roll as claimed in claim 1, in which the scrapers have a setting angle (ss) of a maximum 25 relative to a horizontal straight line drawn through their lower scraping edge.

3. A ground roll as claimed in claim 1 or 2, in which the slots between scrapers adjacent to one another are enlarged towards their rear end.

4. A ground roll as claimed in any of the preceding claims, in which each holder is comprised of an upper part mounted on the crossbeam and a lower part supporting the scraper and in which the lower part is located so as to be displaceable in its longitudinal direction and securable in different positions.

5. A ground roll as claimed in claim 1 or 4, in which the intermediate space (Z) between the leading edge of each holder and the roll jacket of the scraper enlarges upwardly.

6. A ground roll as claimed in claim 5, in which the rear edge of each holder or the lower part thereof at least in its lower region is located within the circular path of the extensions.

7. A ground roll as claimed in any of the preceding claims, in which the crossbeam has a maximum width (B) in the direction of travel which width is less than the radius (R) of the circular paths of the extensions and in which the crossbeam is wholly located above the ground rolls.

8. A ground roll substantially as herein described with reference to and as illustrated in the accompanying drawings.