GB2126958A - Terrain clearance apparatus - Google Patents

Abstract

Terrain clearance apparatus (11) capable of being mounted on a tractor (10) comprises an articulated boom (12) formed by a pair of articulated members (13, 14) mechanically in parallel. The distal end of boom (12) carries a horizontally-extending drive shaft (15) to which a plurality of flail members (16) each in the form of a chain are secured. Boom (12) carries an extension ram (17) and an elevation ram (18) which at one end is mounted on the tractor (10). Hydraulic motors (20) mounted on boom (12) are connected to shaft (15) by belt drives (21). A skirt-like protector mechanism (30) with a wheeled carriage (31) depends from the apparatus (11) to protect tractor (10) from debris thrown up by the chains (16). <IMAGE>

Description

SPECIFICATION Terrain clearance apparatus This invention relates to terrain clearance apparatus.

According to the present invention there is provided terrain clearance apparatus adapted to be mounted on a tractor, said apparatus comprising an articulated boom having boom elevation and extension hydraulic rams, the distal boom end carrying a drive shaft rotatable about a horizontai axis, hydraulic drive means connected to the drive shaft and mounted on the boom for actuation from the tractor, said drive shaft being provided with a plurality of terrain-clearing flail members.

Preferably said flail members are in the form of metal chains. Each chain may conveniently terminate in a plurality of ground-clearing chain fragments at the chain end remote from the drive shaft.

Preferably also the apparatus comprises a protector mechanism located, when the boom is in its in-use extended position, intermediate the ends of the boom. Conveniently the protector mechanism is mounted on a wheel carriage which is adapted for separate attachment to the tractor on which the boom is mounted.

The apparatus of the present invention is useful in clearance of heather and other ground-hugging vegetation and in clearance of explosive devices on or just under the ground surface. In the latter case the protector mechanism preferably comprises a steel plate of sufficient thickness to withstand an explosion and in both cases the purpose of the protector mechanism is to isolate the tractor and its operator (if any) from the operating location of the flail members.

Conveniently the apparatus is adapted to be mounted on a tractor of the agricultural type, that is having front wheels which are steerable and being provided with an auxiliaries drive unit having a hydraulic output. Alternatively the tractor may be of the industrail type, that is having rear wheels which are steerable and being provided with an auxiliariesdrive unit having a hydraulic output. The apparatus of the present invention requires three controlled hydraulic outputs from the auxiliaries drive unit: one for the boom extension ram, one for the boom elevation ram, and one for the drive shaft drive means.

Where the apparatus incorporates a protector mechanism this may be mounted on a hydraulically-powered tractor hitch so as to be adjustable in elevation. The protector mechanism when incorporating wheels may be mounted on a three-point hitch and may be arranged relative to the boom to provide support for the boom when the latter is in its extended in-use position.

The boom may comprise a single articulated member with the drive shaft protruding from opposite sides thereof at its distal end, or the boom may comprise a pair of articulated members arranged in parallel and with the drive shaft extending therebetween at the distal ends thereof.

The boom length may be varied according to the purpose for which the apparatus is designed.

For example, for removal of ground-hugging vegetation the operating location of the flail members may be relatively close to the tractor on which the apparatus is mounted whereas for clearing of explosive devices it is preferred that the operating location of the flail members be relatively remote from the tractor. Furthermore for this latter use it is preferred that the protector mechanism when of the wheeled type has nonpneumatic wheels.

An embodiment of the present invention will now be described by way of example with reference to the accompanying drawings.

In Fig. 1 of the drawings a conventional agricultural tractor 10 carries terrain-clearance apparatus 11 at its front end. Apparatus 11 comprises a boom 12 formed by a pair of articulated members 1 3, 14 mechanically in parallel as will be evident from Fig. 2. The distal end of boom 1 2 carries a horizontally extending drive shaft 15 to which are secured a plurality of flail members 1 6 each in the form of a chain. The members 1 6 extend along the length of shaft 1 5 and are preferably secured thereto at different circumferential positions so that in operation they beat the terrain to be cleared in a sequential fashion.

Boom 12 carries an extension ram 17 and an elevation ram 18, the latter being mounted at one end on the tractor 10. Furthermore hydraulic motor 20 is mounted on the boom 12 and is connected to shaft 1 5 by way of a belt drive 21 which provides a safety feature, by way of slippage, if the members 1 6 become entangled and cause shaft 1 5 to stall. As will be evident from Fig. 2 because of the parallel-member boom construction rams 1 7 and 18 and motor 20 are duplicated.

Apparatus 11 further comprises a protector mechanism 30 comprising a carriage 31 in this instance coupled by means of a universal coupling 32 to the tractor 10 and having non-pneumatic ground engaging wheels 33 which are steerable in tandem with the front wheels of the tractor 10 by hydraulics which although not shown are known per se. Mechanism 30 further includes a steel plate 34 which is pivotally mounted and is positioned by a (duplicated) hydraulic ram 35. As will be evident plate 34 is located to protect motors 20 and rams 17, 1 8 when the boom is in its operating position of Fig. 1 and furthermore extends laterally beyond members 13, 14 and thereby provides additional support at shoulders 36 for the boom 12.

In operation the apparatus 11 is moved to the Fig. 1 position and motors 20 energised as a consequence of which members 1 6 are rotated in the direction of arrow A (although the reverse direction may be used if preferred) thereby causing members 1 6 to flail or beat the terrain 40 which is to be cleared. Any debris which is thrown up by this action impinges against plate 34 and is thereby prevented from damaging either the tractor 10 or selected components of the apparatus 11. When the apparatus 11 is out of use retraction of the boom 12 and of ram 35 permits plate 34 to fold relatively flat onto carriage 31 and shaft 15 and members 16 can then be placed onto plate 34 as shown in Fig. 3. If the apparatus 11 is to be removed from the tractor 10 it can be rendered self-stable on carriage 31 by provision of support leg 39 or alternatively jockey wheels.

It will be evident from the drawings that various accessories are mounted on the tractor 10 for use in conjunction with the apparatus 11. These will not be described in detail but comprise a periscopic operators sight 42; a foam-delivering marker system 44 to delineate the lateral boundaries of terrain cleared; a stapled-tapedelivering marker system 46 for use with or in place of system 44; a rear-mounted tractor winch 48; and tractor-wheel cage extensions 50 for aiding traction on soft ground.

Claims (Filed on 8/9/83) 1. Terrain clearance apparatus adapted to be mounted on a tractor, said apparatus comprising an articulated boom having boom elevation and extension hydraulic rams, the distal boom end carrying a drive shaft rotatable about a horizontal axis, hydraulic drive means connected to the drive shaft and mounted on the boom for actuation from the tractor, said drive shaft being provided with a plurality of terrain-clearing flail members.

2. Apparatus as claimed in claim 1, wherein said flail members are in the form of metal chains.

3. Apparatus as claimed in claim 2, wherein each chain terminates in a plurality of groundclearing chain fragments at the chain end remote from the drive shaft.

4. Apparatus as claimed in any preceding claim, including a protector mechanism located, when the boom is in its in-use extended position, intermediate the ends of the boom.

5. Apparatus as claimed in claim 4, wherein the protector mechanism is mounted on a wheeled carriage which is adapted for separate attachment to the tractor on which the boom is mounted.

6. Apparatus as claimed in claim 5, wherein the protector mechanism is adapted to be mounted on a hydraulically-powered tractor hitch so as to be adjustable in elevation.

7. Apparatus as claimed in claim 6, wherein the protector mechanism incorporates wheels and is arranged relative to the boom to provide support for the boom when the boom is in its extended in-use position.

8. Apparatus as claimed in any preceding claim, wherein the boom comprises a pair of articulated members arranged in parallel with the drive shaft extending therebetween at the distal ends thereof.

9. Terrain clearance apparatus as claimed in claim 1, and substantially as hereinbefore described with reference to the accompanying drawings.

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

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. up by this action impinges against plate 34 and is thereby prevented from damaging either the tractor 10 or selected components of the apparatus 11. When the apparatus 11 is out of use retraction of the boom 12 and of ram 35 permits plate 34 to fold relatively flat onto carriage 31 and shaft 15 and members 16 can then be placed onto plate 34 as shown in Fig. 3. If the apparatus 11 is to be removed from the tractor 10 it can be rendered self-stable on carriage 31 by provision of support leg 39 or alternatively jockey wheels. It will be evident from the drawings that various accessories are mounted on the tractor 10 for use in conjunction with the apparatus 11. These will not be described in detail but comprise a periscopic operators sight 42; a foam-delivering marker system 44 to delineate the lateral boundaries of terrain cleared; a stapled-tapedelivering marker system 46 for use with or in place of system 44; a rear-mounted tractor winch 48; and tractor-wheel cage extensions 50 for aiding traction on soft ground. Claims (Filed on 8/9/83)

1. Terrain clearance apparatus adapted to be mounted on a tractor, said apparatus comprising an articulated boom having boom elevation and extension hydraulic rams, the distal boom end carrying a drive shaft rotatable about a horizontal axis, hydraulic drive means connected to the drive shaft and mounted on the boom for actuation from the tractor, said drive shaft being provided with a plurality of terrain-clearing flail members.

2. Apparatus as claimed in claim 1, wherein said flail members are in the form of metal chains.

3. Apparatus as claimed in claim 2, wherein each chain terminates in a plurality of groundclearing chain fragments at the chain end remote from the drive shaft.

4. Apparatus as claimed in any preceding claim, including a protector mechanism located, when the boom is in its in-use extended position, intermediate the ends of the boom.

5. Apparatus as claimed in claim 4, wherein the protector mechanism is mounted on a wheeled carriage which is adapted for separate attachment to the tractor on which the boom is mounted.

6. Apparatus as claimed in claim 5, wherein the protector mechanism is adapted to be mounted on a hydraulically-powered tractor hitch so as to be adjustable in elevation.

7. Apparatus as claimed in claim 6, wherein the protector mechanism incorporates wheels and is arranged relative to the boom to provide support for the boom when the boom is in its extended in-use position.

8. Apparatus as claimed in any preceding claim, wherein the boom comprises a pair of articulated members arranged in parallel with the drive shaft extending therebetween at the distal ends thereof.

9. Terrain clearance apparatus as claimed in claim 1, and substantially as hereinbefore described with reference to the accompanying drawings.