GB2089183A

GB2089183A - A distribution device for a pneumatic spreader of granular material

Info

Publication number: GB2089183A
Application number: GB8137432A
Authority: GB
Original assignee: Amazonen Werke H Dreyer SE and Co KG
Current assignee: Amazonen Werke H Dreyer SE and Co KG
Priority date: 1980-12-16
Filing date: 1981-12-11
Publication date: 1982-06-23
Also published as: FR2495889B1; GB2089183B; NL188730C; DE3047245C1; NL188730B; FR2495889A1; NL8105366A

Abstract

The device is for a pneumatic spreader of the kind having pipelines, (5) which extend transversely to the direction of travel of the spreader (arrow 3) and which terminate at positions spaced apart in said transverse direction, and a blower for conveying granular material along the pipelines. The device comprises an elbow (1) connected to the outer end(s) of each pipeline. The elbow extends in a horizontal arc so as to discharge material either forwards or rearwards. The elbow has at least two mutually separated guide surfaces (9,10) which commence downstream, when viewed in the direction of material flow, of the region (7) of the elbow against which material issuing from the pipeline (arrows 8) will impinge. The device has a deflector (12) facing the discharge end of the elbow. <IMAGE>

Description

SPECIFICATION A distribution device for pneumatic spreaders of granular material The invention relates to a distribution device for pneumatic spreaders of granular material and more particularly concerns such spreaders of the kind having a plurality of pipelines which extend trans tersely to the intended direction of travel of the spreader and which terminate at positions spaced apart in a direction transverse to said intended direction of travel, and a blower for conveying material along the pipelines.

A known distribution device (see Fed. Rep. of Germany Patentschrift 18841) comprises an elbow which has three individual elbow parts divided from one another by intermediate walls which do not begin prior to the first quarter of its total length and which increase gradually in width. Owing to the division into individual elbow parts a broad spreader fan is advantageously obtained. This fan is characterised in that with appropriate arrangement of the individual distribution devices relative to each other the spreader fans of the individual distribution devices overlap to a large extent. Thus a uniform spread pattern can be obtained.Furthermore, a uniform distribution of the particles of material blown out of the outflow openings over the individual parts of the elbow is to occur in the first quarter of the length of the elbow member, even if, with certain kinds of material in respect of their shape and surface character, they are conveyed by the air stream to a large extent in the lower region of the pipeline.

However, it has been found in agricultural practice and in long term experiments that this uniform distribution, which is imperative for a symmetrical spreaderfan, is ensured only for relatively small discharge quantities. With relatively large discharge quantities of material, e.g. fertiliser an upwardly decreasing density of material occurs within the distribution device; i.e. an asymmetrical spreaded fan is produced. This results in strip formation, amassed grains and harvest losses.

It is an object of the invention to provide an improved distribution device resulting in a uniform and symmetrical spreader fan even with relatively large discharge quantities and above all with types of material which tend to separate out within the pipelines.

The invention provides a distribution device for a pneumatic spreader of the kind hereinbefore defined, the distribution device comprising an elbow for connection to an outer end(s) of each pipeline so as to extend in a generally horizontal arc from the pipeline to discharge granular material, conveyed along the pipeline in the intended direction of travel or in a direction opposite to the intended direction of travel of the spreader, the elbow having at least two mutually separated guide surfaces which commence downstream when viewed in the direction of flow of the granular material, of the region of the elbow against which the granular material issuing from the pipeline will impinge and which terminate at positions spaced apart in a direction transverse to the intended direction of travel of the spreader by a distance several times smaller than that between adjacent outer ends of the peripheries, and a deflector at the discharge end of the elbow.

With a distribution device according to the invention a uniform stream of material occurs within the impingement region of the distribution device and is subsequently divided by the mutually separated guide surfaces in such a manner that a symmetrical spreader fan and a uniform spread pattern of the adjacently disposed distribution devices is obtained.

The invention will now be more particularly described, by way of example, with reference to the accompanying drawings, wherein: Figure 1 is a view from below of one embodiment of a distribution device according to the invention; Figure 2 is a view along line A-B of Figure 1; Figure 3 is a view similar to that of Figure 2 of another embodiment of distribution device according to the invention, the underneath view being identical to that in Figure 1; Figure 4 is a view from below of a further embodiment of a distribution device according to the invention; Figure 5 is a view along line A-B of Figure 4, and Figure Sis a view similar to that of Figure 4 of yet another embodiment of a distribution device according to the invention, the underneath view being identical to that in Figure 4.

Referring to the drawings the distribution device shown therein comprises an elbow 1 having a U-shaped cross-section. The elbow 1 is connected to the outer end of a pipeline 5 by clamps 2. The pipeline 5 extends transverse to the direction of travel indicated by the arrow 3 and is provided with an outflow opening 4. The elbow 1 is rotatable about the longitudinal centre axis 6 of the pipeline 5 and can be fixed in various positions.

The elbow 1 of Figures 1 and 2 assumes a horizontal position and outside a region 7 against which material (indicated by arrows 8) issuing from the pipeline impinges, it has two mutually separated guide surfaces 9 and 10.

Initially the material issuing from the pipeline 5 is distributed uniformly over the height of the elbow 1 before it impinges on the guide surfaces 9 and 10 and is divided into two streams separated from each other, so that subsequently a broad spreader fan is produced by the impingement of these streams on a deflector 12 facing the free or discharge end 11 of the elbows. The guide surface 9 has the same curvature as that of the initial portion 13 of the elbow, i.e. the portion containing the impingement region 7 whereas the guide surface 10 is directed inwards relative to the surface 9.

As shown in Figure 3, the elbow 14, in contrast to the elbow 1, has a cross-section which tapers towards the discharge end 11, and three mutually separated guide surfaces 15, 16, and 17. These guide surfaces are mirror-symmetrical in relation to a plane which extends through the longitudinal centre axis 6 of the pipelines 5 and through a horizontal bisecting plane 18 of the elbow 14. The outer ends 19 of the guide surfaces 15 and 17 are directed inwards relative to the middle guide surface 16 and the middle guide surface 16 has the same curvature as that of the initial portion 13 of the elbow 14. The deflector 12 faces the free or discharge end 11.The mirror-symmetrical division of the guide surfaces 15, 16 and 17 is of advantage particularly with a gravity drop of the stream of material within the elbow 14, because the gravity drop of the stream of material is compensated by such a division of the stream of material by means of the guide surfaces 15, 16 and 17 and thus a symmetrical spreader fan is obtained.

The elbow 20 shown in Figures 4 and 5 has three mutually separated guide surfaces 21,22 and 23. The middle one of the mutually separated guide surfaces 22 has the same curvature as that of the initial portion of the elbow 20. At its discharge end 24 the outer guide surface 21 is spaced inwards of the discharge end of the middle guide surface 22 by a distance a and the other outer guide surface 24, at its discharge end, is spaced inwards of the discharge end 24 of the middle guide surface 22 by a distance 2a.

The elbow member 25 shown in Figure 6 also has three mutually separated guide surfaces 26,27,28.

The guide surface 26 has the same curvature as that of the initial elbow portion of the elbow 25. The guide surfaces 27 and 28 are curved inwards in such a manner that the discharge end of surface 27 is spaced inwards of the discharge end of the surface 26 by a distance a and the discharge end of surface 28 is spaced inwards of the discharge end of the surface 26 by a distance 2a.

The radially outermost walls 30 of the various elbows are rectilinear and vertically disposed.

The elbows and the guide surfaces are of nonrusting and wear-resisting material, so that a long life is obtained, but may only be of such material on their inner surfaces.

Claims

1. A distribution device for a pneumatic spreader of the kind hereinbefore defined, the distribution device comprising an elbow for connection to an outer end(s) of each pipeline so as to extend in a generally horizontal arc from the pipeline to discharge granular material, conveyed along the pipeline, in the intended direction of travel or in a direction opposite to the intended direction of travel of the spreader, the elbow having at least two mutually separated guide surfaces which commence downstream, when viewed in the direction of flow of the granular material, of the region of the elbow against which the granular material issuing from the pipeline will impinge and which terminate at positions spaced apart in a direction transverse to the intended direction of travel of the spreader by a distance several times smaller than that between adjacent outer ends of the pipelines, and a deflector at the discharge end of the elbow.

2. A distribution device as claimed in claim 1, wherein the guide surfaces extend at most over one third of the length of the elbow.

3. a distribution device as claimed in claim 1 and comprising an elbow having three mutually separated guide surfaces, one of the guide surfaces having the same curvature as that of the material impingement region of the elbow, another of the guide surfaces being spaced at its discharge end from the discharge end of said one guide surface by a distance a and the remaining guide surface being spaced at its discharge end from said one guide surface by a distance 2a.

4. A distribution device as claimed in claim 1 and comprising an elbow having at least three mutually separated guide surfaces, the mutually separated guide surfaces of the elbow member being mirrorsymmetrical in relation to a plane which extends at least substantially through the longitudinal centre axis of the pipeline and through the middle of the elbow.

5. A distribution device as claimed in claim 4, wherein the discharge ends of the outer mutually separated guide surfaces of the elbow are disposed radially inwards of the discharge end of the middle guide surface and the middle guide surface has the same curvature as the material impingement region of the elbow.

6. A distribution device as claimed in claim 4, wherein the discharge end of the middle guide surface is disposed radially inwards of the discharge ends of the outer guide surfaces and the outer guide surfaces have the same curvature as the material impingement region of the elbow.

7. A distribution device as claimed in any one of the preceding claims, wherein the radially outermost wall of the elbow is rectilinear in a direction normal to the plane of the arc.

8. A distribution device as claimed in claim 7, wherein the radially outermost wall of the elbow is vertical in use.

9. A distribution device as claimed in claim 1, wherein the elbow has a U-shaped cross-section at least along that portion of its length containing the material impingement region.

10. A distribution device as claimed in any one of the preceding claims, wherein the elbow is of non-rusting and wear-resisting material at least on its inside.

11. A distribution device as claimed in any one of the preceding claims, wherein the elbow and the guide surfaces are of non-rusting and wear-resisting material.

12. Adistribution devicefora pneumatic spread erofthe kind hereinbefore defined, substantially as hereinbefore described with reference to any one of the embodiments shown in the accompanying drawings.

13. A pneumatic spreader having a plurality of pipelines which extend transversely to the intended direction of travel of the spreader and which terminate at positions spaced apart in a direction transverse to said intended direction of travel, a blower communicating with the pipelines and a distribution device as claimed in any one of the preceding claims connected to each outer end of the pipelines.