WO2011054060A1

WO2011054060A1 - Elevatable utility boom

Info

Publication number: WO2011054060A1
Application number: PCT/AU2010/001489
Authority: WO
Inventors: Mark Richard Willcocks
Original assignee: Willcocks Nominees Pty Limited
Priority date: 2009-11-09
Filing date: 2010-11-09
Publication date: 2011-05-12

Abstract

This invention relates to a utility boom for carrying out operations at elevated positions, such as tree trimming. The boom is mounted on a body for location near an object to which an operation is to be carried out, such as near a tree. The boom comprises a first arm mounted to the body and a second arm mounted to the first arm. The inclination and rotation of the first arm relative to the body is adjustable and the inclination and rotation of the second arm relative to the first arm also is adjustable. Accordingly, the position of a remote end of the boom is controllable by adjusting the inclination and rotation of the first arm and the second arm.

Description

ELEVATABLE UTILITY BOOM

Field of the Invention This invention relates to utility booms for carrying out operations at an elevated position. The invention has particular, although not exclusive, application to remote tree-trimming operations. Background of the Invention

Tree-trimming and removal is a dangerous process which generally requires persons to access the tree by Aerial Lift (Elevating Work Platform (EWP) ) , climbing or ladder. There are numerous incidents each year of falls, crushing, electrocution and other hazards that cause death or serious injury.

Generally speaking, current tree-trimming operations involve a worker operating a saw, being a chainsaw, circular saw, hand saw or secateurs. The worker may be on the ground to access relatively low branches or may be in the basket of a cherry-picker, climbing the tree or on a ladder to access higher branches.

Manoeuvrability of the saw plays an important role in ensuring that branches are trimmed correctly to current aboricultural standards. Specifically, when branches are trimmed and the future health of the tree is of concern, the branch should be trimmed perpendicularly to the branch and just beyond a branch bark collar without damaging any other part of the tree.

Also of importance to tree trimming and removals are (a) the safety of other persons assisting and of the cutter themself and (b) the protection of property, for example from falling tree limbs and debris . Tree work is generally hard physical labour in a dangerous environment. Such work for long hours is generally not recommended.

While remotely operated boom mounted saws are known, they have limited manoeuvrability of the saw compared to a worker wielding a saw. This reduced manoeuvrability limits the extent to which remotely operated booms are suited to access branches for trimming and to obtain the correct branch-trimming angle or for removal. For example, access to a tree may be restricted by other branches, fixed objects on the ground, electrical conductors or the terrain .

It is the object of the subject invention to provide a utility boom with an improved range of movement.

Summary of the Invention

The invention provides a utility boom for carrying out operations at elevated positions , the boom being mounted on a body for location near an object to which an

operation is to be carried out, the boom comprising:

(a) a first arm mounted to the body and wherein the inclination and rotation of the first arm relative to the body is adjustable; and (b) a second arm mounted to the first arm and wherein the inclination and rotation of the second arm relative to the first arm is adjustable, wherein the position of a remote end of the boom is controllable by adjusting the inclination and rotation of the first arm and the second arm. Instead of the utility boom being limited to a range of radial directions stemming from the body, the position from which the second arm stems (i.e. where it is mounted to the first arm) can be off-set from the body. This off- set position enables the boom to approach an object from a range of directions that are not available with a single axis of rotation. Accordingly, the utility boom provides improved manoeuvrability because the utility boom is operable to approach an object from a range of angles for a given location of the body. This is an advantage in circumstances when the position of the body is limited and in circumstances when re-positioning the body is too time- consuming . The first arm may be rotatable about a first axis that is generally upright relative to the body.

The second arm may be rotatable about a second axis that is generally upright relative to the body.

The first arm includes a platform and the second arm is mounted on the platform.

The first arm may be configured so as to maintain the platform in a predetermined orientation as the first arms is elevated, whereby causing the second arm to maintain a given angle of inclination.

The remote end of the boom may have means for carrying out an operation according the nature of the means.

The operation means may comprise a range of

interchangeable equipment for enabling a range of

different operations to be carried out.

The operation means may be adapted for tree-trimming operations . In particular, the remote end of the boom preferably has cutting means for trimming limbs and/or branches of trees. The tree-trimming means preferably is a saw mounted on a remote end of the second arm. More preferably, the saw is a chain saw, circular saw or shear. It may also have a grab for holding branches . The operations means preferably is operable remotely via controls located on the body. Alternatively, the operation means may be operable via radio remote controls .

The first and second arm may comprise two or more portions that are telescopically extendible from a transport position to extend the overall reach of the boom.

Extendibility of either the first and second arm enables the boom to be used for a greater range of operations , for example clearing branches from relatively low trees and from relatively high trees .

The first arm and/or the second arm may be formed

partially or wholly from an electrically insulative material.

The electrically insulative material preferably is fibre reinforced plastics and, more preferably, the material is fibreglass. However, it will be appreciated that any material with suitable strength and electrical insulative properties may also be used.

When working at elevated positions around power lines , there is always a risk that the boom or the operator may come into contact with power lines. While the risk of contacting power lines is difficult to control, the applicant has realised that the risk of injury is readily reduced significantly by constructing the boom of

materials that do not conduct electricity. The risk is further reduced by enabling operations to be controlled from a location away from the remote end of the boom.

The first arm may be connected to the second arm by a rotation mechanism. Similarly, the first arm may be connected to the body by another rotation mechanism. The first and second arms may be operated by controls located on the body. Alternatively, the controls may be located remote from the body and the boom.

Preferably, the elevation and rotation of the first and second arms are independently controllable .

The elevation and rotation of the first and second arms are actuated by hydraulic means .

The utility boom may be mounted on a wheeled vehicle so that it is transportable to sites where operations are to be carried out and is manoeuvrable at sites to a desired position.

The wheeled vehicle may be a motorised vehicle or may be a trailer.

The vehicle may have stabilisation means for levelling the body on site and/or for stabilising the body during operation of the boom.

Brief Description of the Drawings

An embodiment of the utility boom will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a side elevation view of an embodiment of a utility boom fitted in a travelling position to a utility vehicle ;

Figure 2 is a side elevation view of the utility boom in Figure 1 fitted to a utility vehicle with the boom in a fully extended position;

Figure 3 is a top view the utility boom in Figure 1 fitted to a utility vehicle with the boom in a first stage of extension;

Figure 4 is a top view the utility boom in Figure 1 fitted to a utility vehicle with the boom in a second stage of extension; and

Figure 5 is a top view the utility boom fitted in Figure 1 to a utility vehicle with the boom in the fully extended position. Detailed description of an embodiment

The description which follows is in the context of an embodiment of the utility boom as a tree-trimming

apparatus. However, it will be appreciated that the utility boom may be used for other applications by fitting alternative operating tools on the remote end of the utility boom to carry out other operations .

A utility boom 10 for trimming trees is shown in Figures 1 to 5.

The boom 10 is mounted on a body, in the form of utility vehicle 20, that is able to be located near trees that are to be trimmed. The boom 10 has a first arm, in the form a dual member linkage 30, mounted to the vehicle 20 and a second arm, in the form of a three-stage arm 40 mounted to the linkage 30. The linkage 30 comprises two parallel linkages 32 that are each connected to a linkage swivel 34 at one end and to a boom swivel 36 at their opposite end. The linkage swivel 34 is mounted to the vehicle 20 and enables the linkage 30 to pivot about a generally vertical axis relative to the vehicle 20 and to pivot through an arc of approximately 180°, thereby enabling the boom swivel to be positioned at a desired point in an arc about the linkage swivel 34.

A lifting ram 38 connects the linkage swivel 34 to the uppermost of the two parallel linkages 32 and can be extended to raise the linkage 30 relative to the vehicle 20. However, it will be appreciated that the lifting ram 38 may be arranged in alternative positions to cause the linkage 30 to be raised to an inclined position.

The arm 40 is formed from three concentric and telescopic stages, 42, 44 and 46. Stage 42 of the arm 40 is linked to the boom swivel 36 via a platform 50 and a further

hydraulic lifting ram 52 extends between the platform 50 and the arm 40 to enable elevation of the arm 40 relative to the platform. The swivel 36 enables the arm 40 to be rotated through a 360° arc relative to the linkage 30.

The parallel configuration of the linkage 30 with two parallel linkages 32 ensures that the boom swivel 36 is maintained in the same orientation for all elevated positions of the linkage 30. This means that the axis of rotation of the arm 40 about the boom swivel 36 remains generally vertical relative to the vehicle 20.

Equipment (not shown) placed on the end of the third stage 46 can be raised to an elevated position by elevation of either or both of the linkage 30 or the arm 40. In

addition, independent swivelling of the linkage 30 and the arm 40 enables elevated positions to be reached by a variety of different paths.

This is important in the event that the most direct paths are blocked by tree limbs or if the risk of contacting power lines is too great via the primary access path. The range of freedom provided by having an extendible boom with two independently elevatable and rotatable portions makes position of the vehicle 20 a relatively low priority when considering how to access an elevated location.

Specifically, without the two independently elevatable and rotatable portions, conventional cherry-pickers must be positioned to provide liner access within a vertical plane intersecting the elevated position and the vehicle which the cherry-picker is mounted. Such a limitation does not apply to the utility boom 10 is with two independently elevatable and rotatable arms .

The range of positions that can be reached by the boom 10 is illustrated in Figures 3, 4 and 5, each of which are drawn to the same scale for direct comparison. The line marked "L" represents the limit of reach of the boom 10 for a given arm 40 extension. The line L in Figure 5 indicates the maximum reach of the boom 10 when the arm 40 is fully extended. It will be appreciated that positions falling within the area bound by the line L can be reached by suitable configurations of the linkage 30 and the arm 40. Positions close to the vehicle 20 can be reached by directing the linkage 30 away from the desired position and by directing the arm 40 back to the desired position.

The region in which the arm 40 overhangs the linkage 30 cannot be reached when the boom 10 is fully retracted. This is not a concern because, in practice, such positions are low and could be accessed by ladder or accessed from the ground by a hand-held saw or hand-held extendable saw.

Maximum vertical reach of the boom 10 is shown in Figure 2 with both the linkage 30 and the arm 40 fully elevated and the arm 40 fully extended. According to one embodiment, this maximum height is about 15m. However it will be appreciated that the reach for alternative embodiments may be greater than 15m. For example, the linkage 30 may be extendible and the arm 40 may have longer telescopic stages 42, 44 and 46 or may have more than three

telescopic stages. Components for causing the arm 40 to extend and retract are housed inside the arm 40 to prevent snagging on objects during operation.

While the boom 10 is mounted on the utility vehicle 20, it will be appreciated that the boom 10 could alternatively be mounted on any type of vehicle, including a trailer. Depending on the size of the vehicle, lateral stabilisers may be fitted to ensure safe use of the boom 10. However, the extent to which lateral stabilisers are required is reduced in the circumstances that the arm 40 is equipped with remotely controlled equipment, thereby reducing the weight, and the torque on the arm 40 that it generates in comparison to the effect of a basket and worker suspended from the utility boom 10.

During transport, the arm 40 is supported and locked to the vehicle 20 by first and second transport supports 60. Once the vehicle 20 is in position for operation, a saw module may be attached to the remote end of the third stage 46. The boom 10 is then unlocked from the transport supports 60 so that the saw module may be positioned for removing branches and limbs from trees .

The arm 40 carries a reel 70 of hydraulic line for

connecting hydraulic pumps with hydraulically operated equipment mounted to the arm 40, such as a saw module. However, the boom may be fitted with pneumatically or electrically powered equipment. In such circumstances, the hydraulic reel 70 would be replaced with other forms of conduits for conveying power to the equipment.

It will be appreciated, however, that power conduits may be located elsewhere on the boom 10 or body 20. Indeed, it will be appreciated that a reel may not be required and that any suitable alternative for conveying power to the equipment may be used instead. If there is a risk of contacting power lines, the arm 40 is formed of an electrically insulative material such a fibre reinforced plastics. In addition, all parts of the boom 10 above the platform 50 may be formed of insulative material, such as fibreglass. The linkage 30 may also be formed of insulative material. In the event that the arm 40 contacts power lines, the vehicle 20 and the operator are safe from electrocution. The preferred material is glass fibre reinforced plastics, but it will be

appreciated that suitable alternative materials may be used provided they have the required electrical insulation and strength properties.

In the claims which follow and in the preceding

description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

Statements in this specification regarding "known" aspects are not to be taken as an admission that the aspects form part of the common general knowledge of a skilled person in Australia or any other jurisdiction.

Claims

CLAIMS :

1. A utility boom for carrying out operations at elevated positions , the boom being mounted on a body for location near an object to which an operation is to be carried out, the boom comprising:

(a) a first arm mounted to the body and wherein the inclination and rotation of the first arm

relative to the body is adjustable; and

(b) a second arm mounted to the first arm and wherein the inclination and rotation of the second arm relative to the first arm is adjustable, wherein the position of a remote end of the boom is controllable by adjusting the inclination and rotation of the first arm and the second arm.

2. The utility boom as defined in claim 1, wherein the first arm is rotatable about a first axis that is generally upright relative to the body.

3. The utility boom as defined in claim 1 or claim 2, wherein the second arm is rotatable about a second axis that is generally upright relative to the body.

4. The utility boom as defined in any one of the preceding claims, wherein the first arm includes a

platform and the second arm is mounted on the platform.

5. The utility boom as defined in claim 4, wherein the first arm is configured so as to maintain the platform in a predetermined orientation as the first arms is elevated, whereby causing the second arm to maintain a given angle of inclination.

6. The utility boom as defined in any one of the preceding claims , wherein a remote end of the boom is able to be equipped with interchangeable operation means for enabling a range of different operations to be carried out.

7. The utility boom as defined in claim 6, wherein the operation means is adapted for tree-trimming

operations .

8. The utility boom as defined in claim 7 , wherein the remote end of the boom is equipped with cutting means for trimming limbs and/or branches of trees.

9. The utility boom as defined in claim 8, wherein the tree-trimming means is a saw or a grab for holding branches .

10. The utility boom as defined in claim 9, the saw is a chain saw, circular saw or shear.

11. The utility boom as defined in any one of claims 6 to 10, wherein the operation means is operable remotely via controls located on the body or operable from a location remote from the body and the boom.

12. The utility boom as defined in claim 11, wherein the operation means is operable via radio remote controls .

13. The utility boom as defined in any one of the preceding claims, wherein the first and second arm may comprise two or more portions that are telescopically extendible from a transport position to extend the overall reach of the boom.

14. The utility boom as defined in any one of the preceding claims, wherein the first arm and/or the second arm may be formed partially or wholly from an electrically insulative material .

15. The utility boom as defined in claim 13, wherein the electrically insulative material is fibre reinforced plastics, such as fibreglass.

16. The utility boom as defined in any one of the preceding claims, wherein the first and second arms are operated by controls located on the body or operable from a location remote from the body and the boom.

17. The utility boom as defined in claim 16, wherein the elevation and rotation of the first and second arms are independently controllable.

18. The utility boom as defined in any one of the preceding claims , wherein the elevation and rotation of the first and second arms are actuated by hydraulic means.

19. The utility boom as defined in any one of the preceding claims , wherein the utility boom is mounted on a wheeled vehicle so that the utility boom is transportable to sites where operations are to be carried out and is manoeuvrable at sites to a desired position.

20. The utility boom as defined in claim 19, wherein the wheeled vehicle is a motorised vehicle or is a

trailer.

21. The utility boom as defined in claim 20, wherein the vehicle includes stabilisation means for levelling the body on site and/or for stabilising the body during operation of the boom.