GB2197573A

GB2197573A - An agricultural implement

Info

Publication number: GB2197573A
Application number: GB08625977A
Authority: GB
Inventors: Malcolm Dean
Original assignee: AGCO Manufacturing Ltd
Current assignee: AGCO Manufacturing Ltd
Priority date: 1986-10-30
Filing date: 1986-10-30
Publication date: 1988-05-25
Anticipated expiration: 2006-10-30
Also published as: GB2197573B; GB8625977D0

Abstract

An agricultural implement comprises a frame (1), a beam (3) that is mounted on the frame (1) so as to extend transversely of the direction of forward motion of the implement having a plurality of tools (4) mounted along the beam so as to engage the ground when in work, the beam comprising a central beam portion (3') and an outer beam portions (3'') connected to the central beam portion so as to be movable to a transport position, and first fluid actuator means (8) adapted to raise or lower the tools into working engagement with the ground, and second fluid actuator means (12) adapted to move the outer beam portions (3'') to the transport position, characterised in that said first and second fluid actuator means are connected in a fluid control system with a manually operable valve (29) which in a first position connects the second fluid actuator means (12) to the same fluid supply line (27) as the first fluid actuator means (8) so that both can be operated simultaneously to raise the tools (14) and move the outer beam portions (3'') to the transport position, the required operating pressure of the first fluid actuator means (8) being lower than that of the second fluid actuator means (12) so that the tools are raised before the outer beam portions are moved to the transport position. <IMAGE>

Description

An Agricultural Implement This invention relates to an agricultural implement having a beam that carries ground engaging tools and is formed with outer portions mounted so that they can be moved inwards to reduce the width of the implement for transportation.

Pneumatic drills generally have a central seed hopper that is located behind the tractor and which supplies seeds pneumatically through pipes to coulters carried on a transverse beam that extends across the width of the drill.

In order to drill a wide bout, a large beam may be provided that projects both sides of the tractor, and for ease of transportation this beam may be formed with outer portions that can be moved inwards of the tractor to reduce the overall width of the drill.

Pneumatic drills are known in which the coulter beam has outer portions that are pivotally connected to the ends of a central beam portion so that they can be folded upwards to the transport position. A separate hydraulic actuator folds each outer portion of the beam, and retaining means is provided to hold each outer portion in the lowered working position.

Pneumatic drills are also known in which a hydraulic actuator serves to raise or lower the coulters into work.

Both the coulter actuators and the beam folding actuators are powered from the hydraulic system of the tractor, and are generally controlled by respective spool valves.

An object of the present invention is to provided an implement of the aforesaid type with safety features that prevent the beam from being moved to the transport position without first raising the coulters out of work, and/or prevent the coulters from being lowered into work whilst the beam remains in the transport position.

According to one aspect , the invention consists in an agricultural implement comprising a frame, a beam that is mounted on the frame so as to extend transversly of the direction of forward motion of the implement and that has a plurality of tools mounted along the beam so as to engage the ground when in work, the beam comprising a central beam portion and an outer beam portion each side that is connected to the central beam portion so as to be movable to a transport position, and first fluid actuator means adapted to raise or lower the tools into working engagement with the ground, and second fluid actuator means adapted to move the outer beam portions to the transport position, characterised in that said first and second fluid actuator means are connected in a fluid control system with a manually operable valve that serves to connect the second fluid actuator means to the same fluid supply line as the first fluid actuator means so that both can be operated simultaneously to raise the tools and move the outer beam portion to the transport position, the required operating pressure of the first fluid actuator means being lower than that of the second fluid actuator means so that the tools are raised before the outer beam portions are moved to the transport position.

The manually operable valve thus controls movement of the tool-carrying beam of the implement to the transport position, and serves to ensure that the tools are raised out of work before such movement is initiated, thereby to protect the implement against damage. For example, a pneumatic seed drill having a folding beam cannot be folded up without the coulters first being raised out of working engagement with the soil.

According to another aspect, the invention consists in an agricultural implement comprising a frame,a beam that is mounted on the frame so as to extend transversely of the direction of forward motion of the implement and that has a plurality of tools mounted along the beam so as to engage the gound when in work, the beam comprising a central beam portion and an outer beam portion each side that is connected to the central beam portion so as to be movable to a transport position, and first fluid actuator means adapted to raise or lower the tools into working engagement with the ground, and second fluid actuator means adapted to move the outer beam portions to the transport position, characterised in that said first and second fluid actuator means are connected in a fluid control system including a manually operable valve having a first position in which is connects the second fluid actuator means to the same fluid supply line as the first fluid actuator means so that both can be operated simultaneously to raise the tools and move the outer beam portions to the transport position, and a second position in which it isolates the second fluid actuator means and connects the first fluid actuator means to said fluid supply line so that the tools can be lowered into work, said manually operable valve having a control handle located so that when set into the valve in the first position to raise the coulters and move the outer beam portions to the transport position, part of one of the outer beam portions moves to obstruct the handle and prevent it from being moved to the second position.

The manually operable valve thus controls movement of the tool-carrying beam of the implement to the transport position, and by virtue of being retained in position by the beam once in the transport position, it serves to prevent the tools being lowered into work without first lowering the beam to the work position, thereby protecting the implement against damage. For example, a pneumatic seed drill having a folding beam cannot be operated to lower the coulters into work whilst the beam is folded.

Preferably, a check valve is connected between the fluid supply line and the first fluid actuactor means so as to allow pressurisation of the coulter to raise the tools, the check valve being by-passed by the manually operable valve when the latter is in the second position so as to allow depressurisation of the first fluid actuator means.

The invention will now be described by way of example with reference to the accompanying drawings in which Figure 1 is a rear view of a pneumatic drill according to the invention, Figure 2 is a side view of the drill of Figure 1, Figure 3 is rear perspective view of one side of the drill of Figure 1, Figure 4 is a side perspective view of the drill of Figure 1 showing the outer beam portions raised to the transport positions, and Figure 5 is a diagram of hydraulic circuitry that controls the coulters and control beam of the drill of Figure 1.

The illustrated drill comprises a frame 1 carrying a seed hopper 2 and a transversely extending control beam 3 on which are mounted a plurality of coulters 4. A plurality of seed metering mechanisms 5 dispense seed from the hopper into pneumatic distribution means 6 that conveys the seed in a flow of air to each coulter.

The control beam 3 is supported in rotary bearings 7 attached to the frame that allow the beam to rotate about its longitudinal axis, and a hydraulic ram 8 is connected between the frame 1 and a lever arm 9 on the beam 3 so astro rotate the latter and force the coulters into working engagement with the ground.

The control beam 3 is formed as a folding beam comprising a centre portion 3' lying within the width of the hopper, the frame and the landwheels, and an outer portion 3" pivotally connected to each end of the central portion so as to be pivotable upwards to a transport position. The pivotal connection is formed by an upright hinge 10 adapted to receive a removable retaining pin 11 to hold the hinge closed with the outer portion lowered.

A hydraulic ram 12 is connected between posts 13 at the inner end of each outer portion 3" and is operated to raise both outer portions simultaneously.

The centre and outer portions 3', 3" of the control beams 3 are formed from square-section tube for strength and lightness. The outer portions 3" can be as long as the centre portion 3', and in order to resist flexing they are braced at their outer ends by a strut assembly 14 each side that is pivotally connected to the adjacent side wall 15 of the hopper 2 and folds upwards with the respective outer portion 3".

Each strut assembly 14 comprises a rectangular framework pivotally connected to the side wall 15 of the hopper at two spaced points 16 so as to form a horizontal, fore and aft pivot axis. The outer end of the strut assembly is pivotally connected to the outer end of the outer portion 3" of the control beam 3 by a connection comprising an elongated round section member 17 that is a telescopic slide fit within the outer end portion 3" and is pivotally connected by a bolt 18 to the outer end of the strut framework 14.

A flange 19 on the end of the elongated member 17 abuts the end of the outer portion 3" when the latter is in the fully lowered work position. A removable retaining pin 20 engages a pair of lugs 21 on the outer end of the outer portion 3" and co-operate with the flange 19 to retain the elongated member 17 in its fully inserted position within the outer portion 3". The outer portion 3" is then locked in its lowered work position and is braced against both horizontal and vertical flexing by the strut framework 14.

The retaining pin 20 is removed to release the elongated member 17, and the retaining pin 11 is removed to release the inner hinge 10 so that both outer portions 3" of the beam can be folded by the hydraulic ram 12 to the raised transport position (Figures 1 and 4). The elongated members 17 are then extended from the outer portions and serve to further guide and support the outer portions.

Once in the transport position (Figure 4), each outer portion 3" can be locked in position by means comprising a forward extension 22 on the front face of the outer portion 3" that engages between a pair of outwardly projecting lugs 23 on the inner end of the strut framework 14, and a retaining pin 24 that is inserted between aligned holes in the extension 22 and lugs 23.

The hydraulic ram 8 that operates the coulter 4, and the hydraulic ram 12 that folds the beam 3 to the transport position, are both connected in a hydraulic control circuit (Figure 5) that is coupled to a single spool valve 25 of the tractor hydraulic system. The spool valve 25 has a neutral control position (shown in Figure 5), a work position with the spool moved to the left in Figure 5, and a raise position with the spool moved to the right in Figure 5. In the raise position, the spool valve connects the pressure supply 26 to the line 27, and fluid flows through a check valve 28 to the ram 8 to extend the latter and raise the coulters.

The ram 12 is connected as a single-acting ram with a connection via a manually operable two-way valve 29 to the line 27. In a first position (shown in broken line in Figure 5), the valve 29 connects the ram 12 to the line 27 so that it is pressurised together with the ram 8 so that the ram 12 retracts to lift both outer beam portions 3" to the transport position. However, the two rams 8, 12 are adapted so that the required operating pressure of the ram 8 is lower than that of the ram 12 so that the former operates first to raise the coulters out of work before the ram 12 operates to lift the outer portions 3" of the beam to the transport position.

The manually operable valve 29 is mounted on the side wall 15 of the hopper and has a control handle 30 that lies against the side wall 15 when the valve is in said first position to lift the outer portions 3" of the beam. The valve 29 is also located so that part of the framework of the strut 14 overlaps the handle 30 when in the transport position (Figure 4) so as to prevent the handle from being operated.

When the outer portions 3" of the beam are lowered in the work condition, the handle 30 can be swung outwards away from the side wall 15 of the hopper to change the to valve 29 to its second position (shown in full lines in Figure 5).

In this second position, the valve 29 isolates the ram 12 so that it remains in its fully extended position with both outer beam portions 3" lowered. Also, the valve 29 connects the ram 8 directly to the line 27, by-passing the check valve 28 so that the ram 8 is effectively double-acting. If the spool valve 25 is now moved to the right in Figure 5 to connect the line 27 to reservoir 31 and the second line 32 of the ram 8 to the pressure supply 26, the ram 8 is retracted as fluid flows through the valve 29, line 27 and spool valve 25 to the reservoir 31. The beam 3 is therefore rotated to move the coulters into work. It will be appreciated that if the outer portions 3" of the beam are in the transport position and the valve 29 is retained in said first position, operation of the spool valve 25 to retract ram 8 and operate the coulters will not be effective because the return fluid flow is blocked by the check valve 28 and valve 29.

It will be appreciated that whilst the invention has been described with reference to a pneumatic seed drill having fluid actuated tools carried on a beam that is folded by fluid actuated means, the invention can be applied to any agricultural implement where hydraulic actuation of ground engaging tools and hydraulic actuation of a folding beam can usefully be interlocked for reasons of safety.

Claims

Claims

l.An agricultural implement comprises a frame, a beam that is mounted on the frame so as to extend transversely of the direction of forward motion of the implement and that has a plurality of tools mounted along the beam so as to engage the ground when in work, the beam comprising a central beam portion and an outer beam portion each side that is connected to the central beam portion so as to be movable to a transport position, and first fluid actuator means adapted to raise or lower the tools into working engagement with the ground, and second fluid actuator means adapted to move the outer beam portions to the transport position, characterised in that said first and second fluid actuator means are connected in a fluid control system with a manually operable valve that serves to connect the second fluid actuator means to the same fluid supply line as the first fluid actuator means so that both can be operated simultaneously to raise the tools and move the outer beam portions to the transport position, the required operating pressure of the first fluid actuator means being lower than that of the second fluid actuator means so that the tools are raised before the outer beam portions are moved to the transport position.
2.An implement as claimed in claim 1 in which the manually operable valve has a first position in which it connects the second fluid actuator means to the same fluid supply line as the first fluid actuator means, and a second position in which it isolates the second fluid actuator means and connects the first fluid actuator means to said fluid supply line so that the tools can be lowered into work.
3.An implement as claimed in claim 1 in which a check valve is connected between the fluid supply line and the first fluid actuator means so as to allow pressurisation of the latter to raise the tools, the check valve being by-passed by the manually operable valve when the latter is in the second position so as to allow de-pressurisation of the first fluid actuator means.
4.An implement as claimed in claim 1 or 2 in the form of a seed drill in which the tools comprise coulters and the outer beam portions are pivotally connected to the central beam portion either side of the central seed hopper.
5.An agricultural implement comprises a frame, a beam that is mounted on the frame so as to extend transversely of the direction of forward motion of the implement and that has a plurality of tools mounted along the beam so as to engage the ground when in work, the beam comprising a central beam portion and an outer beam portion each side that is connected to the central beam portion so as to be movable to a transport position, and first fluid actuator means adapted to raise or lower the tools into working engagement with the ground, and second fluid actuator means adapted to move the outer beam portions to the transport position, characterised in that said first and second fluid actuator means are connected in a fluid control system including a manually operable valve having a first position in which it connects the second fluid actuator means to the same fluid supply line as the first fluid actuator means so that both can be operated simultaneously to raise the tools and move the outer beam portions to the transport position, and a second position in which it isolates the second fluid actuator means and connects the first fluid actuator means to said fluid supply line so that the tools can be lowered into work, said manually operable valve having a control handle located so that when set with the valve in the first position to raise the coulters and move the outer beam portions to the transport position, part of one of the outer beam portions moves to obstruct the handle and prevent it from being moved to the second position.
6.An implement as claimed in claim 1 in which a check valve is connected between the fluid supply line and the first fluid actuator means so as to allow pressurisation of the latter to raise the tools, the check valve being by-passed by the manually operable valve when the latter is in the second position so as to allow de-pressurisation of the first fluid actuator means.
7.An implement as claimed in claim 1 or 2 in the form of a seed drill in which the tools comprise coulters and the outer beam portions are pivotally connected to the central beam portion either side of a central seed hopper, the manually operable valve being mounted on one side wall of the seed hopper and being located so that the adjacent outer beam portion co-operates with the handle of the valve.
8.A seed drill substantially as herein described with reference to the accompanying drawings.