17 May 1996

Now automation further refines plough design

By Andy Collings

HOW much more can be done to refine the design of the plough? Variable width furrows, auto-reset bodies, greater underbeam clearance – all have been done before.

But now Dowdeswell has added automation. The companys new 180 Series Delta Furra semi-mounted ploughs are fitted with an electro-hydraulic system, the DEC system, which automatically operates the headland turning sequence – raise, rotate, steer and lower.

And there is more. Once in work, the ploughs front furrow width, furrow width and depth can be set and stored so that on returning to work after a headland turn, the plough automatically readopts these positions.

Key to the system is an in-cab control box which can receive and send signals to the plough and is capable of being operated both in manual mode – for initial setting up – and automatic.

So how does it work and how is the system set up? To initiate the whole system, the operator must first insert a key and release a stop button – a feature which ensures the plough can be made safe to work on (by removing the key) and provides an instant over-ride to turning sequences, if required.

When ploughing begins, the operator selects manual mode and uses three switches to adjust front furrow width, furrow width and rear depth wheel position, simply by holding the switch open until the correct setting is reached.

A fourth input relates to the length of the plough to make the rear furrow lift clear of the ground after the front furrow to create a straight headland. This is activated by a preset number of depth wheel rotations after the main linkage has been raised.Once the settings have been made, the operator loads this information and selects automatic mode.

Arriving at the headland the front linkage is raised and the turning sequence automatically begins. Once the rear furrow is clear the depth wheel turns to full lock, activated by a sensor on the ploughs headstock pivot point. At this point it is worth noting that the plough can be safely turned at 90í from the tractor without fear of damage to rear tyres or mudguards.

During the turn, the plough is reduced to its narrowest position before the bodies are rotated – an arrangement which keeps the ploughs centre of gravity as low as possible. As the turn continues and the tractor starts to line up for the next bout, the operator presses a steering button on the control box to change the angle of the depth wheel to bring the plough square for work.

The main linkage is lowered and the plough enters work once more having automatically returned all settings to their required position.

A brief return to manual mode allows on-the-move adjustments to be made to cater for siding ground or in-field obstructions. Setting the front furrow width to its minimum position enables the front furrow to run empty behind the tractor wheel, reducing draft requirement when say, ploughing up steep hills.

Impressive as the system is, relieving operator stress and increasing work rates, there are perhaps down-sides. Not least is the price, which for a seven-furrow version (five- and six-furrow versions are available) with Auto-reset bodies carries a list price of £24,589.

There is also the ploughs length to consider. A pivoting headstock that leaves sufficient space for tight headland turns means there has to be a significant distance between the tractor and the front furrow.

And, with another six furrows following with 99cm (39in) point-to-point clearance, overall length is not to be ignored.

Tight 90deg turns with Dowdeswells 180 series semi-mounted reversibles. Inset:In-cab, DECbox overrides auto control of body reversing sequence. Flagship price:£24,589.