GB2118413A

GB2118413A - Soil cultivating apparatus

Info

Publication number: GB2118413A
Application number: GB08310709A
Authority: GB
Inventors: Fred Alan Jones
Original assignee: National Research Development Corp UK
Current assignee: National Research Development Corp UK
Priority date: 1982-04-20
Filing date: 1983-04-20
Publication date: 1983-11-02
Also published as: GB2118413B; GB8310709D0

Abstract

Soil cultivating apparatus is provided including a cultivating tool (24) for entering into the soil, and control means (26, 27, 28) responsive to the force exerted on the tool by an obstacle (31) encountered by the tool as the tool is drawn through the soil to lift the tool out of the soil. In a preferred embodiment, a spring biased latch (28) holds a control arm (26) hinged to a secondary member (25) itself hinged to the main frame (22) of the apparatus, and the soil-cultivating tool extends from the control arm. A ground engaging pad (27) on the control arm levers the tool out of the ground when the tool is released by the latch in response to an excessive force thereon due to the obstacle. <IMAGE>

Description

SPECIFICATION Soil cultivating apparatus This invention relates to soil cultivating apparatus and is especially applicable to apparatus known as subsoilers, in which a cultivating tool or tine penetrates and disturbs the sub-soil layer.

To avoid breakage of a tine in a subsoiler, the mounting of the tine on the main frame of the subsoiler is typically by two bolts, one of which is of smaller diameter than the other so that, on meeting an obstruction which might otherwise damage the tine, the smaller bolt shears, allowing the tine to pivot clear of the obstruction about the larger bolt. in rocky areas of the country, subsoilers have been found to be of limited use, because rocks in the subsoil layer cause repeated shearing of the bolts, requiring frequent stops during the subsoiling operation to instal new shearable bolts. This can lead operators to replace the shearable bolts with stronger bolts in the hope that the tine will then drag aside any, or at least most, obstructions.However, this practice frequently leads to breakage of the tines, and can even lead to damage to the tractor to which the subsoiler is connected.

These problems are overcome, in accordance with the invention, by providing soil cultivating apparatus including at least one cultivating tool for entering into the soil, and control means responsive to the force exerted on the tool by an obstacle encountered by the tool as the tool is drawn through the soil, whereby the tool is caused to lift rearwardly out of the soil relative to the direction of travel.

According to one preferred embodiment of the invention, the soil cultivating apparatus comprises: a) a main support membersecurableto a towing vehicle such as a tractor; b) at least one secondary member pivoted thereto at the front end thereof relative to the direction of travel of the device in use; c) a soil cultivating tool pivotally suspended from the or each secondary member; d) a control arm extending transversely to the or each tool and carrying a ground-engaging member at the front end thereof; and e) a force sensitive release means holding the control arm or arms or each control arm against movement relative to the relative secondary member and to the main support member until a pre-determined force tending to pivot the control arm relative to the secondary member is exceeded.

When the cultivating tool meets an obstruction in the soil, the force due to the resistance to movement of the obstruction is transmitted thereby to the release means, which when the pre-determined force is exceeded, allows the control arm to pivot, thereby lifting the cultivating tool out of the soil.

The release means preferably comprises a spring ora hydraulic cylinder controlling a latch engaging the control arm, the cylinder being provided, for example with an unloading valve which releases all the hydraulic pressure from the cylinder when a predetermined pressure is exceeded. The unloading valve may be re-set, after it has released the pressure, either manually or by an automatic device, such as an electric solenoid, operated in response to repositioning of the apparatus for continued cultivation.

The apparatus can be used in any type of soil, the release loading of the unloading valve being varied accordingly.

Reference is made to the drawings in which: Fifure lisa schematic elevation of an apparatus in accordance with one embodiment of the invention, shown at the moment of contact between a tine and a buried obstruction; and Figure 2 is a corresponding view, the apparatus having advanced by a short distance.

In each Figure, the position of the towing vehicle, for example an agricultural tractor, relative to the apparatus, is indicated schematically by the rear wheel 21 thereof. The apparatus comprises a generally rectangular frame 22, coupled to the three point coupling typically provided on tractors, and having guide wheels 23 at the front end thereof. The tine 24 is pivotally mounted on a mounting beam 25 which is itself pivotally mounted on the front end of the frame 22. A control arm, 26 extends generally perpendicular to the tine 24 on the upper end thereof, and carries a pivoting control pad 27 at its frontmost end. The rear end of the control arm 26, in the operative position of the apparatus, lies along the beam 25. A second such mounting beam 25 and associated tine 24 and control arm 26 are mounted on the frame 22 generally parallel to the first.The control arms 26 are held against pivoting relative to the beams 25 by a spring-biased latching member 28 pivoted to the rear end of the frame 22.

In use, the apparatus is drawn along by the tractor, and when the tine 24 comes into contact with a buried obstacle such as a rock 31, the resistance to movement produces an upward force in the rear end of the control arms 26. When a pre-determined force is exceeded, this force being determined by the spring tension, which may be variable if desired, the latching member 28 moves rearwardly, thus releasing the arms 26 to pivot. The pivoting of the arms 26 has two effects. Firstly, the tines 24 pivot rearwardly, and secondly, the beams 25 are lifted and pivot relative to the frame 22, thus causing the tines 24 to lift.

As the control pads 27 come into contact with the ground, the control arms 26 then pivot about the pads 27. This accelerates the rearward and upward motion of the tines 24 so that they move rearwardly quicker than the forward motion of the frame, thus reducing and removing the contact force between tine 24 and rock 31, and avoiding the risk of damage.

The tines are lifted into the frame 22 and clear of the soil, as shown in Figure 2. To re-set the tines in position for further cultivation, the operator need only lift the whole frame vertically until the weight of the tines causes the arms and tines to reassume the working positions, and the latching members 28 re-engage the control arms 26.

1. Soil cultivating apparatus including at least

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Soil cultivating apparatus This invention relates to soil cultivating apparatus and is especially applicable to apparatus known as subsoilers, in which a cultivating tool or tine penetrates and disturbs the sub-soil layer. To avoid breakage of a tine in a subsoiler, the mounting of the tine on the main frame of the subsoiler is typically by two bolts, one of which is of smaller diameter than the other so that, on meeting an obstruction which might otherwise damage the tine, the smaller bolt shears, allowing the tine to pivot clear of the obstruction about the larger bolt. in rocky areas of the country, subsoilers have been found to be of limited use, because rocks in the subsoil layer cause repeated shearing of the bolts, requiring frequent stops during the subsoiling operation to instal new shearable bolts. This can lead operators to replace the shearable bolts with stronger bolts in the hope that the tine will then drag aside any, or at least most, obstructions.However, this practice frequently leads to breakage of the tines, and can even lead to damage to the tractor to which the subsoiler is connected. These problems are overcome, in accordance with the invention, by providing soil cultivating apparatus including at least one cultivating tool for entering into the soil, and control means responsive to the force exerted on the tool by an obstacle encountered by the tool as the tool is drawn through the soil, whereby the tool is caused to lift rearwardly out of the soil relative to the direction of travel. According to one preferred embodiment of the invention, the soil cultivating apparatus comprises: a) a main support membersecurableto a towing vehicle such as a tractor; b) at least one secondary member pivoted thereto at the front end thereof relative to the direction of travel of the device in use; c) a soil cultivating tool pivotally suspended from the or each secondary member; d) a control arm extending transversely to the or each tool and carrying a ground-engaging member at the front end thereof; and e) a force sensitive release means holding the control arm or arms or each control arm against movement relative to the relative secondary member and to the main support member until a pre-determined force tending to pivot the control arm relative to the secondary member is exceeded. When the cultivating tool meets an obstruction in the soil, the force due to the resistance to movement of the obstruction is transmitted thereby to the release means, which when the pre-determined force is exceeded, allows the control arm to pivot, thereby lifting the cultivating tool out of the soil. The release means preferably comprises a spring ora hydraulic cylinder controlling a latch engaging the control arm, the cylinder being provided, for example with an unloading valve which releases all the hydraulic pressure from the cylinder when a predetermined pressure is exceeded. The unloading valve may be re-set, after it has released the pressure, either manually or by an automatic device, such as an electric solenoid, operated in response to repositioning of the apparatus for continued cultivation. The apparatus can be used in any type of soil, the release loading of the unloading valve being varied accordingly. Reference is made to the drawings in which: Fifure lisa schematic elevation of an apparatus in accordance with one embodiment of the invention, shown at the moment of contact between a tine and a buried obstruction; and Figure 2 is a corresponding view, the apparatus having advanced by a short distance. In each Figure, the position of the towing vehicle, for example an agricultural tractor, relative to the apparatus, is indicated schematically by the rear wheel 21 thereof. The apparatus comprises a generally rectangular frame 22, coupled to the three point coupling typically provided on tractors, and having guide wheels 23 at the front end thereof. The tine 24 is pivotally mounted on a mounting beam 25 which is itself pivotally mounted on the front end of the frame 22. A control arm, 26 extends generally perpendicular to the tine 24 on the upper end thereof, and carries a pivoting control pad 27 at its frontmost end. The rear end of the control arm 26, in the operative position of the apparatus, lies along the beam 25. A second such mounting beam 25 and associated tine 24 and control arm 26 are mounted on the frame 22 generally parallel to the first.The control arms 26 are held against pivoting relative to the beams 25 by a spring-biased latching member 28 pivoted to the rear end of the frame 22. In use, the apparatus is drawn along by the tractor, and when the tine 24 comes into contact with a buried obstacle such as a rock 31, the resistance to movement produces an upward force in the rear end of the control arms 26. When a pre-determined force is exceeded, this force being determined by the spring tension, which may be variable if desired, the latching member 28 moves rearwardly, thus releasing the arms 26 to pivot. The pivoting of the arms 26 has two effects. Firstly, the tines 24 pivot rearwardly, and secondly, the beams 25 are lifted and pivot relative to the frame 22, thus causing the tines 24 to lift. As the control pads 27 come into contact with the ground, the control arms 26 then pivot about the pads 27. This accelerates the rearward and upward motion of the tines 24 so that they move rearwardly quicker than the forward motion of the frame, thus reducing and removing the contact force between tine 24 and rock 31, and avoiding the risk of damage. The tines are lifted into the frame 22 and clear of the soil, as shown in Figure 2. To re-set the tines in position for further cultivation, the operator need only lift the whole frame vertically until the weight of the tines causes the arms and tines to reassume the working positions, and the latching members 28 re-engage the control arms 26. CLAIMS

1. Soil cultivating apparatus including at least one cultivating tool for entering into the soil, and control means responsive to the force exerted on the tool by an obstacle encountered by the tool as the tool is drawn through the soil to lift the tool out of the soil.

2. Apparatus according to Claim 1, comprising: a) a main support member securable to a towing vehicle; b) at least one secondary member pivoted thereto at the front end thereof relative to the direction of travel of the apparatus in use;

c) a soil cultivating tool pivotally suspended from the or each secondary member; d) a control arm extending from the or each tool and carrying a ground-engaging member at the forward end thereof; and e) a force sensitive release means holding the control arm or arms or each control arm against movement relative to the relative secondary member and to the main support member until the force on the tool tending to pivot the control arm relative to the secondary member exceeds a predetermined value.

3. Apparatus according to Claim 2, wherein the release means comprises a latch engaging the control arm and a force sensitive element controlling release of the latch.

4. Apparatus according to Claim 3, wherein the force sensitive element is a spring.

5. Apparatus according to Claim 3, wherein the force sensitive element is a hydraulic cylinder.

6. Apparatus according to Claim 5, wherein the hydraulic cylinder is provided with an unloading valve which releases all the hydraulic pressure from the cylinder when a predetermined pressure is exceeded.

7. Apparatus according to Claim 6, wherein the unloading valve has manually operable re-setting means.

8. Apparatus according to Claim 6, comprising re-setting means arranged to re-set the unloading valve when the latch re-engagesthecontrol arm.

9. Apparatus according to Claim 6,7 or 8, wherein the unloading valve is adjustable to permit selection of the predetermined release pressure.

10. Soil cultivating apparatus, substantially as described with reference to, or as shown in, the drawings.