GB2157933A - Trashboards for ploughs - Google Patents

Abstract

A trashboard 12 for mounting on a plough body 18 is adapted for bodily movement relative to the body in a vertical direction so that the optimum position of the trashboard may be maintained over a range of ploughing depths. The forward lower edge of the trashboard is in sliding contact with the plough body in such adjustment and is chamfered to enable flush contact with the body. <IMAGE>

Description

SPECIFICATION Trashboardsfor ploughs This invention relates to trashboards for ploughs.

The traditional attachments used on ploughsfor burying trash are skim coulters and trashboards. A skim coulter used either by itself or in conjunction with a rotating disc coulter, is placed forward of the plough body and skims off the top layer of soil - including the stubble and green growth -which is deposited atthe bottom of the furrow. This ensures that all weeds are well covered with the maximum depth of soil on top to prevent subsequent regrowth. It also leaves a clean surface on the field to aid subsequent drilling and germination of seed.

The conventional trashboard, which is particularly popular in parts ofcontinental Europe, usually replaces a skim and abuts the top edge ofthe ploughboard near the front and forms an upward extension of the mouldboard. It is both cheaper and lighter than a skim. Its action is similarto a skim but differs in some important aspects. Thus, the action of the trashboard on the soil occurs at a later stage of the inversion process than the action of a skim. The trash is mixed in with thefurrow slice as the mouldboard is inverting it, whereas a skim deposits the trash at the bottom of the furrow before the soil is turned on top of it The resulting action of the trash board is to mix the trash relatively homogeneously throughout the cross section ofthe inverted soil.The conventional trash board may result in inferior weed control and a less clean field surface but the more uniform distribution of the trash is of great advantage when incorporating straw.

Decomposing straw releases toxins which inhibits root growth of the succeeding crop. An even mix ofthe straw in the soil increases the rate of decomposition so that most of the toxins are released before the roots have developed sufficiently to reach the buried straw.

A more even distribution will also reduce the concentration of toxins so avoiding the risk of root damage and subsequent yield depression.

For a trash board to function efficiently, it must be correctly positioned vertically with respect to the furrow slice. If, for example, the trashboard is positioned too high on the mouldboard, insufficient soil will reach the trash board and poor mixing of the trash will result.

It is an object of this invention to provide an improved trashboard which achieves thorough mixing oftrash over a range of ploughing depths.

Accordingly, the present invention consists in one aspect in a trashboard for mounting on a plough with a forward portion thereof abutting a plough body and a rearward portion shaped to promote mixing of trash in soil turned by the plough body, wherein the trash board is adapted for bodily movement relative to the plough body in a generallyvertical direction, such adjustment enabling the optimum position ofthe trashboard to be maintained over a range of ploughing depths.

Advantageously the forward portion of the trashboard slides overthe plough body in said adjusting movement expose greater or lesser amounts ofthe plough bodytothesoil.

Preferably said forward portion ofthetrashboard has a lower edge in contact with the plough body, the plane of thetrashboard adjacent said lower edge being inclined to the plane of the plough body at said contact.

The invention will now be described byway of example with reference to the accompanying drawings in which Figure lisa side view of a trashboard according to this invention mounted on a plough body, Figure 2 is a frontview corresponding to Figure 1, Figure 3 is a detailed view showing parts of the trashboard and plough body of Figure 1.

Referring to the drawings,thetrashboard 10 comprises a forward portion 12 to which is bolted a support block 14 and a rearward portion 16 which is curved away from the plough body 18. The support block 14 is adjustably mounted,through bolt 20, on a bracket 22 which is in turn secured through bolts 24 (only one seen in the drawings) to the frog 25. As shown in Figure 3, the bracket 22 is formed with a vertically directed slot 26 for cooperation with the bolt 20. The bracket 22 is formed with a step 28 adjacent the top edge of the plough bodysothatthefrontfacesof the bracket and the plough body are contiguous.The support block 14 is of generally V-shaped cross section so that the forward portion of the trash board is inclined at an acute angletothe plane ofthe plough body in the area of contact. The lower edge of the trashboard in theforward portion 12 is chamfered at 30 to provide substantiallyflush contact between the trashboard and the plough body.

By loosening the bolt 20the trashboard and integral support block may be moved vertically with respect to the bracket 22 and plough body 18. In this movement, theforward portion ofthetrashboardslidesoverthe plough body exposing greater or lesser amounts of the plough body to the soil. Thus in the position shown in full lines in Figures 1 and 2 there is a significant overlap between the trashboard and the plough body.

This position would correspond usually to a shallow ploughing depth. In the position shown in dotted outline, the trashboard is towards the top of its range of vertical movement and there is no overlap. It will be understood that adjustment in this sense enables the position ofthetrashboard to be optimised over a range of ploughing depths. Thus, at a relatively shallow ploughing depth,thetrashboard may be moved downwardlyto ensure that sufficient soil meets the trash board to provide efficient mixing. The optimum position of the trashboard will depend not only on the depth of work but also on the soil type and forward speed.The vertical adjustment according to the present invention, combined with rotational and longitudinal adjustmentofthetrashboard,will enable good mixing ofthetrashto be obtained atshallower plough depths than hitherto possible and should provide better trash coverage over a range of plough depths than is normallyachievablewith conventional The drawing(s) originally filed was (were) informal and the print here reproduced is taken from a later filed formal copy.

trash boards.

Because the bracket22 is tangential to the adjoining surface of the plough body-the step 28 ensuring that the joint is flush -the support block 14 can slide smoothly over its range of movement, the chamfer 30 ensuring thatthere is a smooth transition, as presented to the soil, between the plough body and the trashboard.

This invention has been described by way of example only and a variety of modifications are possible without departing from the scope of the invention. The exact shape of the trashboard, for example, is not of the essence ofthis invention and whilstthe described trash board has a bifurcated rearward portion, other configurations are possible.

Similarly, whilst the use of a support block integral with the trash board and slidably mounted relative to a fixed bracket is thought to have advantages, it would be possible in an alternative construction to have a suitably shaped bracket bolted to the trash board and slidable with the trash board relative to the plough body. In another modification, the trashboard may be mounted otherwise than directly on the plough body, for example on the plough leg.

Claims (7)

1. Atrashboard for mounting on a plough with a forward portionthereof abutting a plough bodyanda rearward portion shaped to promote mixing of trash in soil turned by the plough body, wherein the trash.

board is adapted for bodily movement relative to the plough body in a generallyvertical direction, such adjustment enabling the optimum position ofthe trashboardto be maintained overa range of ploughing depths.

2. Atrashboard according to Claim 1, wherein said forward portion ofthetrashboardslides overthe plough body in said adjusting movement to expose greater or lesser amounts of the plough body to the soil.

3. Atrashboard according to Claim 1 orClaim2, wherein the forward portion of the trash board has a lower edge in contact with the plough body, the plane ofthetrashboard adjacent said lower edge being inclined to the plane of the plough body at said contact.

4. Atrashboard according to Claim 3, wherein said lower edge is chamfered to enable substantially flush contact between the forward portion of the trashboard and the plough body.

5. Atrashboard according to any one of the preceding claims wherein the trashboard is provided with an integral support block slidably cooperable with a bracket adapted for mounting adjacentthe plough body.

6. Atrashboard according to Claim 5,wherein the surface of the mounted bracket over which the support block slides is tangential to the adjoining surface ofthe plough body.

7. Atrashboard substantially as hereinbefore described with reference to and as shown in the accompanying drawings.