GB2185371A

GB2185371A - Straw incorporation apparatus

Info

Publication number: GB2185371A
Application number: GB08601019A
Authority: GB
Inventors: Duncan Macintyre
Original assignee: National Research Development Corp UK
Current assignee: National Research Development Corp UK
Priority date: 1986-01-16
Filing date: 1986-01-16
Publication date: 1987-07-22
Also published as: GB8601019D0

Abstract

An apparatus 10 comprises first and second helically-bladed soil-working rotors 15, 16 co-operating to mix surface straw and stubble into the soil, the second assembly of rotors 16 splitting the ridges formed by the first assembly of rotors 15. Each rotor may comprise two helically-bladed sections of opposite hand. <IMAGE>

Description

SPECIFICATION Straw incorporation apparatus The present invention relates to straw incorporation apparatus for mixing surface straw into the ground.

To deal with straw which perhaps in the future cannot be burnt, it is generally agreed that one of the best methods is to finely chop the straw, spread it over the stubble and then somehow mix and incorporate it with the top 150 mm of soil. It is an object of the present invention to provide an apparatus which will perform this action effectively.

According to the present invention, an apparatus for incorporating loose straw and stubble into the ground comprises a first soilworking assembly operative to form the soil into one or more first ridges and a second soil-working assembly operative to form one or more second ridges by splitting the first ridges to move the upper parts of the first ridges into the furrows between the first ridges and working the newly exposed lower parts of the first ridges.

Preferably, the first and second assemblies are followed by a soil-levelling means operative to flatten the second ridges by moving material from the upper parts of the second ridges into the furrows between the second ridges.

Conveniently, the soil-working assemblies comprise helically-bladed rotors.

Preferably, each said rotor comprises two helically-bladed sections of opposite hand.

Conveniently, the envelope swept out by the helical blades tapers in the sideways direction.

Conveniently, the pitch of the helical blades changes progressively, e.g. increasing in the direction of soil movement.

Conveniently, the rotors are multi-bladed.

An embodiement of the invention will now be described, by way of example only, with reference to the accompanying part diagrammatic drawing in which Figure 1 shows a plan view of a preferred embodiment of the invention and Figure 2 shows a side view of one of the soil-working rotors used in the embodiment of Fig. 1.

Thus referring now to the drawings, an apparatus 10 for incorporating a surface layer of straw into the soil comprises first and second soil-working assemblies 12 and 13.

Each soil-working assembly comprises a number of soil-working rotors 15, 16, the two units 16 of the second assembly 13 being staggered relative to the three rotors 15 of the first assembly.

A typical axial spacing between the adjacent tips of adjacent rotors is about 27 cm.

The rotors are powered from the tractor p.t.o. shaft 18 by means of a bevel gearbox 19 and chain and sprocket drives 20, 21.

Reference numerals 23, 24 illustrate the support shafts for the rotors, each shaft being driven to rotate the rotors into the soil in the opposite sense to the land wheel rotation, typically at about 120 r.p.m. for a forward machine speed of 94 metres per minute.

As will be seen from the drawing, each rotor 15, 16 comprises two sets of helicallybladed sections 26, 27 separated by a central disc 28. The diameter of the multi-start rotor blades tapers away from a value of say 56 cm at the vertical mid plane of the unit to 25 cm at the tip.

The blades of each pair of sections 22, 23 are of opposite hand so as in operation to move the soil away from the rotor.

Measured relative to the plane of disc 28, the pitch of the rotor blading increases progressively from a value of 0 at the disc, through a value of about 10 4 cm away from the disc and up to a value of about 22 at the tip of the rotor section 30 cm away from the disc. Looked at end on, along the rotation axis of the rotor, the blading wraps around about 300 of the rotor section hub in passing from the disc 28 to the rotor tip.

Optionally, the apparatus is completed by a suitable levelling means (not shown), e.g.

deflector boards or tines fixed to the rear of the machine or a flexicoil roller or the like.

Reference numerals 30, 3 1 respectively indicate two land wheels and the linkage for attaching the machine to the towing tractor.

In operation, as the machine moves forward in direction A, the rotors 15 will move the ground forwardly and sidewardly at about 45" to the direction of travel of the machine to form the ground into ridges the top halves of which are composed of a well distributed mixture of soil and surface straw.

The rotors 1 6 operate to split the ridges formed by the rotors 15, so that the top (mixed) part of these ridges falls into the furrow between them whilst the soil at the base of the ridges is mixed with the previously undistributed layer of straw to be reformed as new ridges of well-mixed soil and straw.

If present, the levelling means now operates to smooth out the new ridges and leave behind it a more level surface.

In a variation of the embodiment above described, the rotors 15, 16 carry outwardly projecting rods in place of the helical-blades shown in the drawing, the rods conveniently being arranged and dimensioned so as in operation to sweep out substantially the same envelope as the blades.

1. An apparatus for incorporating loose straw and stubble into the ground comprising a first soil-working assembly operative to form the soil into one or more first ridges and a second soil-working assembly operative to form one or more second ridges by splitting the first ridges to move the upper parts of the

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Straw incorporation apparatus The present invention relates to straw incorporation apparatus for mixing surface straw into the ground. To deal with straw which perhaps in the future cannot be burnt, it is generally agreed that one of the best methods is to finely chop the straw, spread it over the stubble and then somehow mix and incorporate it with the top 150 mm of soil. It is an object of the present invention to provide an apparatus which will perform this action effectively. According to the present invention, an apparatus for incorporating loose straw and stubble into the ground comprises a first soilworking assembly operative to form the soil into one or more first ridges and a second soil-working assembly operative to form one or more second ridges by splitting the first ridges to move the upper parts of the first ridges into the furrows between the first ridges and working the newly exposed lower parts of the first ridges. Preferably, the first and second assemblies are followed by a soil-levelling means operative to flatten the second ridges by moving material from the upper parts of the second ridges into the furrows between the second ridges. Conveniently, the soil-working assemblies comprise helically-bladed rotors. Preferably, each said rotor comprises two helically-bladed sections of opposite hand. Conveniently, the envelope swept out by the helical blades tapers in the sideways direction. Conveniently, the pitch of the helical blades changes progressively, e.g. increasing in the direction of soil movement. Conveniently, the rotors are multi-bladed. An embodiement of the invention will now be described, by way of example only, with reference to the accompanying part diagrammatic drawing in which Figure 1 shows a plan view of a preferred embodiment of the invention and Figure 2 shows a side view of one of the soil-working rotors used in the embodiment of Fig. 1. Thus referring now to the drawings, an apparatus 10 for incorporating a surface layer of straw into the soil comprises first and second soil-working assemblies 12 and 13. Each soil-working assembly comprises a number of soil-working rotors 15, 16, the two units 16 of the second assembly 13 being staggered relative to the three rotors 15 of the first assembly. A typical axial spacing between the adjacent tips of adjacent rotors is about 27 cm. The rotors are powered from the tractor p.t.o. shaft 18 by means of a bevel gearbox 19 and chain and sprocket drives 20, 21. Reference numerals 23, 24 illustrate the support shafts for the rotors, each shaft being driven to rotate the rotors into the soil in the opposite sense to the land wheel rotation, typically at about 120 r.p.m. for a forward machine speed of 94 metres per minute. As will be seen from the drawing, each rotor 15, 16 comprises two sets of helicallybladed sections 26, 27 separated by a central disc 28. The diameter of the multi-start rotor blades tapers away from a value of say 56 cm at the vertical mid plane of the unit to 25 cm at the tip. The blades of each pair of sections 22, 23 are of opposite hand so as in operation to move the soil away from the rotor. Measured relative to the plane of disc 28, the pitch of the rotor blading increases progressively from a value of 0 at the disc, through a value of about 10 4 cm away from the disc and up to a value of about 22 at the tip of the rotor section 30 cm away from the disc. Looked at end on, along the rotation axis of the rotor, the blading wraps around about 300 of the rotor section hub in passing from the disc 28 to the rotor tip. Optionally, the apparatus is completed by a suitable levelling means (not shown), e.g. deflector boards or tines fixed to the rear of the machine or a flexicoil roller or the like. Reference numerals 30, 3 1 respectively indicate two land wheels and the linkage for attaching the machine to the towing tractor. In operation, as the machine moves forward in direction A, the rotors 15 will move the ground forwardly and sidewardly at about 45" to the direction of travel of the machine to form the ground into ridges the top halves of which are composed of a well distributed mixture of soil and surface straw. The rotors 1 6 operate to split the ridges formed by the rotors 15, so that the top (mixed) part of these ridges falls into the furrow between them whilst the soil at the base of the ridges is mixed with the previously undistributed layer of straw to be reformed as new ridges of well-mixed soil and straw. If present, the levelling means now operates to smooth out the new ridges and leave behind it a more level surface. In a variation of the embodiment above described, the rotors 15, 16 carry outwardly projecting rods in place of the helical-blades shown in the drawing, the rods conveniently being arranged and dimensioned so as in operation to sweep out substantially the same envelope as the blades. CLAIMS

1. An apparatus for incorporating loose straw and stubble into the ground comprising a first soil-working assembly operative to form the soil into one or more first ridges and a second soil-working assembly operative to form one or more second ridges by splitting the first ridges to move the upper parts of the first ridges into the furrows between the first ridges and working the newly exposed lower parts of the first ridges.

2. An apparatus as claimed in Claim 1 in which the first and second assemblies are followed by a soil-levelling means operative to flatten the second ridges by moving material from the upper parts of the second ridges into the furrows between the second ridges.

3. An apparatus as claimed in Claim 1 or Claim 2 in which the soil-working assemblies comprise helically-bladed rotors.

4. An apparatus as claimed in Claim 3 in which each said rotor comprises two helicallybladed sections of opposite hand.

5. An apparatus as claimed in Claim 3 or Claim 4 in which the envelope swept out by the helical blades tapers in the sideways direction.

6. An apparatus as claimed in any of Claims 3 to 5 in which the pitch of the helical blades changes progressively.

7. An apparatus as claimed in Claim 6 in which the pitch of the blades increases in the direction of soil movement.

8. An apparatus as claimed in any Claims 3 to 7 in which the rotors are multi-bladed.

9. An apparatus substantially as hereinbefore described with reference to and/or as illustrated in the accompanying drawing.