GB2169784A - Cut material distribution in a harvesting machine - Google Patents

Abstract

A harvesting machine is provided with a dressing cylinder comprising dressing elements (11) arranged on a base body (7). In one embodiment (Fig. 1) the base body is a cylinder having dressing elements of progressively varying length, the shortest being at the centre, the longest at the ends of the body. Fig. 2 illustrates a second embodiment in which the base body (7) has an obtuse-angled shape through being formed from two parts which are connected in the manner of conical frustums with their narrow ends abutting each other. The dressing element (11) extend over the entire length of the cylinder and have a uniform radial length, so that the diameter of the cylinder reduces from each end thereof to its centre. <IMAGE>

Description

SPECIFICATION Cut material distribution in a harvesting machine The present invention relates to a harvesting machine and has particular reference to an automative swath mower having a dressing cylinder or distributor which permits a large width of deposit for the harvest material taken up in the swath.

To obtain qualitatively good fodder, the harvest stalk material is mowed with the aim, after cutting, of obtaining a short drying time, for which purpose cut material should be spread over the ground as widely and loosely as possible. In that case, the density of the material stream and the throwing width are important if a wide, thin swath is to be achieved, different dressing equipment being used for this purpose.

Thus, swath-shaping equipment, particularly for automotive swath mowers, is disclosed in DD-PS 122 630, the equipment being arranged downstream of a dressing device consisting of a buckling cylinder pair. The equipment consists of guide rods which point outwardly from the throwing direction at an acute angle from the centre of the mower, are straight or bent in this direction and project into the parabola of throw of the harvested material. The material thrown off by the dressing equipment is thrown against the guide rods of the swath-shaping equipment and, due to their narrower course of curvature by comparison with the parabola of throw, is pressed agsinst this. This produces a change in direction of the material in direction of the bent guide rods, whereby the material is spread out to the width of the swath-shaping equipment during the throwing operation.

The disadvantage of a construction of that kind is the required high power in order to transfer sufficient impulsion to the material through a correspondingly high circumferential speed and to obtain a parabola of throw allowing a large width of deposit to be achieved.

In DD-PS 210 595 there is disclosed a cutting mechanism with dressers in which a functional union of cutting mechanism and dresser is realised. For this purpose a carrier cylinder with dresser elements, which are mounted in several axial planes on the carrier cylinder in helical shape in direction towards a transverse conveyor worm, are mounted on an axle of the worm. The worm conveys the mowed material to the dresser which rotates at a substantially higher speed than the worm, whereby the material seized by the dresser elements is deflected and thrown off approximately tangentially to the circumference of the dresser. Due to the frusto-conical structuring of the dresser and the helical course of the dresser elements, a uniform distribution of the material over the entire width of deposit is achieved.The disadvantages of this cutting mechanism with dressers are the complicated, helical arrangement of the dresser elements on the carrier cylinder, the high manufacturing and assembly effort involved in the uniting of the worm and dresser and the required additional drive of the dresser.

In addition, in DE-OS 2 007 511 there is disclosed a method and device for the dressing of stalk material on the field with a high throughput rate, wherein the material experiences a high acceleration and is thrown once or several times against a resistance moving perpendicularly to the direction of material flow, which causes the material to be continuously deflected by this at a sharp angle into a new direction of flow and then deposited in a loose swath. The ribs or strips of the buckling rollers can be arranged parallel to the cylinder axis, in helical lines, or possibly in arrow shape.

It is a disadvantage of this device that the dresser cylinder, when used in conjunction with an oscillating cutting mechanism with trough and worm arranged downstream, is not matched to the higher occurrence of material at the sides compared with the middle of the cylinder and the material, which is disposed within the width of the cylinders and to be deposited, is dressed and conveyed with a uniformly high circumferential speed, leading to an energy consumption substantially greater than required for the deposit.

It would thus be desirable to provide a material distributor which is matched to the form of the local occurrence of material and which, without excessive driving and power requirement, transmits a constant energy to the material over the entire length of the distributor and achieves a uniform deposit width.

According to the present invention there is provided a harvesting machine provided with a rotatable distributor for distributing cut material, the distributor comprising a rotatable elongate member provided around its circumference with projecting conveying elements so arranged that the free ends of the elements lie on the circumference of a notional rotational body which reduces in diameter from the ends of the elongate member towards its centre.

Expediently, the conveying elements are dimensioned and arranged in such a manner that their radial length reduces from the member ends towards the member middle and the notional body possesses a concavely curved or obtuse-angled shape. Apart from a cylindrical shape of the elongate member, on which elements of different length are arranged, it is possible for the member to be formed by two frusto-conical bodies with their conical frustum points abutting each other and for the conveying elements on the circumference of these bodies totbe of equal length. Since the concentration of material in the case of an oscil lating cutting mechanism with drum and transverse conveyor worm is greatest at the side regions, the shape of the distributor is matched to the occurrence of harvested stock.

The diameter of the distributor is dimensioned at its ends as to provide such a rotational speed as to transmit to the material energy sufficient to cause, for example in conjunction with downstream fixed guide plates, a width of deposit greater than the width of the distributor. The material which is conveyed in the middle of the distributor is deposited in a region of the width of the distributor, for which a lower throw energy is required.

A harvesting machine embodying the invention may have the advantage that constructional cost is lower compared with dressing cylinders with uniform diameter extending over the entire width of the cylinder and energy consumption can be kept to a minimum.

Moreover, the cylinder shape makes a low installation height possible and is adapted to the road profile, whereby traffic regulations are met during road transport and ground contact and deformation of the conveying elements is avoided during field transport or a spooling effect is avoided during reverse travel.

Embodiments of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which: Figure 1 is a view of a dressing cylinder of a first harvesting machine embodying the invention; Figure 2 is a view of a dressing cylinder of a second harvesting machine embodying the invention; Figure 3 is a partly sectional side elevation of a harvesting machine embodying the invention, the machine being fitted with an adaptor; Figure 4 is a schematic front elevation of a harvesting machine without the adapter; and Figure 5 is a schematic plan view of a harvesting machine, with illustration of cutting and wide deposit, embodying. the invention.

Referring now to the drawings, there is shown a harvesting machine 1 with an adapter 2 which has a cutting mechanism 3, a drum 4 and a transverse conveyor worm 5, and behind which is mounted a dressing cylinder 6 driven by way of drive elements of the machine 1. For this purpose, a respective stub shaft 8 and 8' is connected to each end of a base body 7 of the cylinder 6 and mounts the cylinder to be rotationally movable in bearings in a frame 9 of the machine 1. For the drive of the cylinder 6, a drive transmission member 10 is mounted on the shaft 8 and connected with the drive unit of the machine 1. The cross-section of the body 7 of the cylinder 6 can have different shapes and fastened to the body 7 are dressing elements 11, the dimensions of which are such that the cylinder 6 narrows from its ends towards its middle and generates a parabolic, concave rotational section.If the body 7 possesses a cylindrical shape as illustrated in Fig. 1, the radial length of the elements 11 reduces from the cylinder ends towards the cylinder middle. If the body 7 is constructed to be obtuse-angled from rotational bodies which are connected with the conical frustum ends abutting each other and extending from the middle outwardly, as illustrated in Fig. 2, the dressing elements 11 can have a uniform radial length extending over the entire length of the cylinder.

The cut harvested material fed from the drum 4 to the conveyor worm 5 is conveyed by the worm from both sides so far towards the middle of the cutting mechanism trough 12 that the resulting compressed swath possesses the width of the dressing cylinder 6 and is fed thereto by way of a metal transfer plate 13, the outer shape of which is assimilated to the cylinder 6. The fed material is entrained by the elements 11 and thrown off rearwardly. In that case, the stock dressed in the middle of the cylinder is deposited within the width of the cylinder, in which case only a small amount of energy need be imparted to the material. Since, however, the occurrence of material is considerably higher in the side regions, a substantially higher throw energy must be transmitted to the material in these regions in order to achieve a wide deposit and this is realised by way of the rotational speed of the cylinder 6. Due to the shape of the cylinder 6 with its elements 11, the circumfer entiai speed is correspondingly higher at the cylinder ends. The dressed material is thrown, with throw energy varying over the cylinder length, between the cylinder 6 and a guide hood 14, which is matched to the shape of the cylinder 6 and has a uniform conveying gap 15 over the entire length of the cylinder.

The material is thrown against downstream fixed metal guide plates 16, by which it is deflected into a deposit direction corresponding to the deflection angle of the plates 16 and thrown off over a wide area.

Claims (1)

1. A harvesting machine provided with a rotatable distributor for distributing cut material, the distributor comprising a rotatable elongate member provided around its circumference with projecting conveying elements so arranged that the free ends of the elements lie on the circumference of a notional rotational body which reduces in diameter from the ends of the elongate member towards its centre.

2. A harvesting machine as claimed in claim 1, wherein the circumference of the notional body is concavely curved between the ends of the elongate member.

3. A harvesting machine as claimed in claim 1, wherein the circumference of the notional body conically reduces in diameter from each end of the elongate member to the centre of the member.

4. A harvesting machine as claimed in claim 3, wherein the elongate member has the form of two conical frustrums abutting at their narrower ends, the conveying elements being of equal length.

6. A harvesting machine substantially as hereinbefore described with reference to Figs.

1, 3 and 4 of the accompanying drawings.

7. A harvesting machine substantially as hereinbefore described with reference to Figs.

2 to 4 of the accompanying drawings.

8. A harvesting machine substantially as hereinbefore described with reference to Figs.

3 to 5 of the accompanying drawings.