GB2158019A

GB2158019A - Soil compression apparatus

Info

Publication number: GB2158019A
Application number: GB08411468A
Authority: GB
Inventors: Charles David Bealby
Original assignee: BEALBY PATRICIA MARY MARGUERIT
Current assignee: BEALBY PATRICIA MARY MARGUERIT
Priority date: 1984-05-04
Filing date: 1984-05-04
Publication date: 1985-11-06
Also published as: GB8411468D0

Abstract

Soil compression apparatus attachable to a wheeled vehicle such as a tractor (1, 2, 3) for preparing a seedbed, drilling and so forth, comprises at least one roller or parallel wheel (5) assembly mounted on a chassis, and suspension means (6) by which the chassis can be coupled to the vehicle between the front (3) and rear (2) wheels so as to be vertically movable beneath the vehicle. Hydraulically operated means, such as rams (7) attached between the suspension means (6) and the vehicle serve to apply downward pressure to the chassis, and means, such as a by-pass valve in hydraulic circuit are provided for adjusting and regulating that pressure. <IMAGE>

Description

SPECIFICATION Soil compression apparatus This invention relates to an apparatus which is intended to be mounted between the wheels of a vehicle for the purpose of compressing the soil in the preparation of a seedbed, drilling and so forth. The invention also consists in a wheeled vehicle, such as an agricultural tractor, when equipped with such apparatus located between front and rear wheel axles. Known proposals for soil compression apparatus have usually involved the use of a roller mounted frontally of a vehicle but the resultant increased front weight has given rise to difficulty in adjusting the roller compaction or compression to match the ground pressure of tractor wheels and also causes steering difficulties and failure to transfer weight from the tractor itself, onto the apparatus.

According to the invention, soil compression apparatus comprises at least one roller or parallel wheel assembly mounted on a chassis, suspension means by which the chassis can be coupled to a vehicle between the vehicle wheels so as to be vertically movable beneath the vehicle, hydraulically operated means attachably between the suspension means and the vehicle for applying downward pressure to the apparatus chassis, and means for adjusting and regulating that pressure. Normally the vehicle will have front and rear wheel axles and the apparatus will be mounted inwardly of the wheels within the wheel base.

A preferred embodiment of the invention is diagramatically illustrated in the accompanying drawings and is hereinafter described. In these drawings: Figure 1 is a side elevation; Figure 2 is a plan view; Figure 3 is a front elevation; and Figures 4 and 5 show different states of an hydraulic circuit.

The drawings show, in chain-dashed lines, the profile of a conventional agricultural tractor with a body 1, rear driving wheels 2 and front steerable wheels 3.

The soil compression apparatus is located between the axles of the front and rear tractor wheels and comprises a chassis 4 on which there is mounted two parallel sets of pneumatictyred ground wheels 5 or alternatively two parallel rollers.

The wheels 5 in one set are staggered in relation to the wheels in the other set. The centre of gravity of the chassis with its wheel or roller sets is directly beneath the centre of gravity of the tractor. The chassis 4 is pivotally suspended from the rear lower end of a pair of suspension bars 6, one on each side of the chassis, which have their upper front ends pivotally connected to fixed points on the tractor.

For applying downward pressure to the chassis 4 and wheels 5, in order to compress the soil as the tractor moves along, a pair of hydraulically operated rams 7, one on each side of the chassis are connected between the respective suspension bars and the tractor body.

As shown in Figures 4 and 5 the rams 7 form part of an hydraulic circuit including a by-pass valve 8 and a pressure gauge 9. The by-pass valve 8 may be operated by a double-acting spool valve and is spring loaded and adjustable to maintain a predetermined and constant downward thrust by the rams, the hydraulic pressure being adjusted so that the average ground pressure on the soil across the whole width of the tractor is constant. The exact pressure which is being applied at any particular moment can be observed from the pressure gauge 9 which is easily visible through the tractor windscreen. The rams 7 are also used for lifting the apparatus at the end of each tractor pass and for transport purposes between sites. In the raised position of the rams the oil supply thereto is terminated.

In Figure 4 the arrows indicate the directions of flow of hydraulic fluid when the rams 7 are being extended to apply downward pressure to the chassis 4 and thence to the soil, any excess fluid released by the valve 8 being caused to flow directly between the fluid supply line and the fluid exhaust line. By contrast, in Figure 5 the arrows indicate the hyd raulicfluid in flow paths when the rams 7 are being retracted for the purposes mentioned above.

It is an advantage of the present invention that the downward thrust of the rams has the effect of raising the tractor and in consequence reducing the downward thrust of the tractor driving wheels, thus reducing their compaction effect upon the soil. It has been found that when the apparatus is fitted to a tractor having low ground pressure tyres the apparatus can result in a lower overall ground pressure than that exerted by most crawler tractors.

The ability to ensure uniform soil compaction across the whole working width of a tractor means that fewer traverses of the ground may be neces sary, and that a more level seedbed with much reduced overall compaction can be achieved.

The mode of construction which has been hereinabove described may enable a standard apparatus to be manufactured and supplied with different attachment brackets to adapt it for fitting to most tractor models, it being possible to match the downwardly exerted thrust to the ground pressure of any tractor wheels.

1. Soil compression apparatus comprising at least one roller or parallel wheel assembly mounted on a chassis, suspension means by which the chassis can be coupled to a vehicle between the vehicle wheels so as to be vertically movable beneath the vehicle, hydraulically operated means attachable between the suspension means and the vehicle for applying downward pressure to the chassis, and means for adjusting and regulating that pressure.

2. A wheeled vehicle equipped with soil compression apparatus comprising at least one roller or parallel wheel assembly mounted on a chassis, suspension means by which the chassis is coupled to the vehicle between front and rear wheel axles of the vehicle so as to be vertically movable beneath the vehicle, hydraulically operated means attached

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Soil compression apparatus This invention relates to an apparatus which is intended to be mounted between the wheels of a vehicle for the purpose of compressing the soil in the preparation of a seedbed, drilling and so forth. The invention also consists in a wheeled vehicle, such as an agricultural tractor, when equipped with such apparatus located between front and rear wheel axles. Known proposals for soil compression apparatus have usually involved the use of a roller mounted frontally of a vehicle but the resultant increased front weight has given rise to difficulty in adjusting the roller compaction or compression to match the ground pressure of tractor wheels and also causes steering difficulties and failure to transfer weight from the tractor itself, onto the apparatus. According to the invention, soil compression apparatus comprises at least one roller or parallel wheel assembly mounted on a chassis, suspension means by which the chassis can be coupled to a vehicle between the vehicle wheels so as to be vertically movable beneath the vehicle, hydraulically operated means attachably between the suspension means and the vehicle for applying downward pressure to the apparatus chassis, and means for adjusting and regulating that pressure. Normally the vehicle will have front and rear wheel axles and the apparatus will be mounted inwardly of the wheels within the wheel base. A preferred embodiment of the invention is diagramatically illustrated in the accompanying drawings and is hereinafter described. In these drawings: Figure 1 is a side elevation; Figure 2 is a plan view; Figure 3 is a front elevation; and Figures 4 and 5 show different states of an hydraulic circuit. The drawings show, in chain-dashed lines, the profile of a conventional agricultural tractor with a body 1, rear driving wheels 2 and front steerable wheels 3. The soil compression apparatus is located between the axles of the front and rear tractor wheels and comprises a chassis 4 on which there is mounted two parallel sets of pneumatictyred ground wheels 5 or alternatively two parallel rollers. The wheels 5 in one set are staggered in relation to the wheels in the other set. The centre of gravity of the chassis with its wheel or roller sets is directly beneath the centre of gravity of the tractor. The chassis 4 is pivotally suspended from the rear lower end of a pair of suspension bars 6, one on each side of the chassis, which have their upper front ends pivotally connected to fixed points on the tractor. For applying downward pressure to the chassis 4 and wheels 5, in order to compress the soil as the tractor moves along, a pair of hydraulically operated rams 7, one on each side of the chassis are connected between the respective suspension bars and the tractor body. As shown in Figures 4 and 5 the rams 7 form part of an hydraulic circuit including a by-pass valve 8 and a pressure gauge 9. The by-pass valve 8 may be operated by a double-acting spool valve and is spring loaded and adjustable to maintain a predetermined and constant downward thrust by the rams, the hydraulic pressure being adjusted so that the average ground pressure on the soil across the whole width of the tractor is constant. The exact pressure which is being applied at any particular moment can be observed from the pressure gauge 9 which is easily visible through the tractor windscreen. The rams 7 are also used for lifting the apparatus at the end of each tractor pass and for transport purposes between sites. In the raised position of the rams the oil supply thereto is terminated. In Figure 4 the arrows indicate the directions of flow of hydraulic fluid when the rams 7 are being extended to apply downward pressure to the chassis 4 and thence to the soil, any excess fluid released by the valve 8 being caused to flow directly between the fluid supply line and the fluid exhaust line. By contrast, in Figure 5 the arrows indicate the hyd raulicfluid in flow paths when the rams 7 are being retracted for the purposes mentioned above. It is an advantage of the present invention that the downward thrust of the rams has the effect of raising the tractor and in consequence reducing the downward thrust of the tractor driving wheels, thus reducing their compaction effect upon the soil. It has been found that when the apparatus is fitted to a tractor having low ground pressure tyres the apparatus can result in a lower overall ground pressure than that exerted by most crawler tractors. The ability to ensure uniform soil compaction across the whole working width of a tractor means that fewer traverses of the ground may be neces sary, and that a more level seedbed with much reduced overall compaction can be achieved. The mode of construction which has been hereinabove described may enable a standard apparatus to be manufactured and supplied with different attachment brackets to adapt it for fitting to most tractor models, it being possible to match the downwardly exerted thrust to the ground pressure of any tractor wheels. CLAIMS

2. A wheeled vehicle equipped with soil compression apparatus comprising at least one roller or parallel wheel assembly mounted on a chassis, suspension means by which the chassis is coupled to the vehicle between front and rear wheel axles of the vehicle so as to be vertically movable beneath the vehicle, hydraulically operated means attached between the suspension means and the vehicle for applying downward pressure to the chassis, and means for adjusting and regulating that pressure.

3. Avehicle as claimed in claim 2 in which the centre of gravity of the roller or parallel wheel assembly is directly below the centre of the gravity of the vehicle.

4. An apparatus or vehicle as claimed in any of claims 1 to 3 in which the suspension means comprises bars which are pivotally attachable at their respective ends to the apparatus chassis and the vehicle, and the hydraulically operated means are hydraulic rams attached to the bars.

5. An apparatus or vehicle as claimed in any of claims 1 to 4 in which the means for adjusting and regulating the downward pressure applied to the chassis is a by-pass valve installed in the hydraulic circuit which includes the hydraulically operated means or rams.

6. An apparatus or vehicle as claimed in any of claims 1 to 5 in which two sets of parallel wheels are supported by the chassis and the wheels of one set are staggered relative to the wheels of the other set.

7. An apparatus or vehicle as claimed in any of claims 2 to 6 including a pressure gauge for continuously indicating hydraulic fluid pressure in the circu it which includes the hydraulically operated means or rams as a measure of the downward pressure being applied to the soil by the wheels or rollers.

8. Atractor mounted soil compression apparatus substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.