GB2233599A

GB2233599A - Pole-mounted chain saw for tree pruning

Info

Publication number: GB2233599A
Application number: GB8915267A
Authority: GB
Inventors: Simon Richard Pallister; Patrick John Gilbert Sanders
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-07-04
Filing date: 1989-07-04
Publication date: 1991-01-16
Anticipated expiration: 2009-07-04
Also published as: GB8915267D0; GB2233599B

Abstract

A small power-operated chain-saw (12) is mounted on top of a rigid pole or series of connected poles (13) with an operating handle (14) at the bottom end of the pole(s). The arrangement enables an operator to carry out power trimming and branch pruning from distances greater than his reach with normal hand-held power tools, and improves a great deal on the scope and efficiency of traditional manual extension tools. The chain-saw (11) may be replaced with a reciprocating blade cutter or trimmer. The cutting head is mounted on a variable-position joint (19) so that the plane of the cuts it makes relative to the axis of the mounting pole(s) can be altered. <IMAGE>

Description

"POWERED POLE-SAW" This invention relates to a power operated saw mounted on top of a pole.

The pruning and trimming of the smaller branches of trees and hedges that are beyond normal standing reach can at present be carried out from the ground using either a "parrot's beak" type of shear operated by a wire or cord and mounted on a long pole or by a fixed saw blade on a pole which is manually moved up and down to provide the cutting action.

The former method has limitations as to si of branch that can be cut and the latter, in addition to requiring much time and physical labour, is also prone to entrapment of the flat blade in the cut by the movements of the sawn branch. The only current practical alternative to these two methods is to raise the operator to branch height with a hand saw, power saw or trimmer by mechanical hoist, by ladder or by climbing.

This invention will allow an operator to prune and trim trees and hedges at a height well beyond normal reach from ground level with minimum physical effort and much saving of time. In addition it will be possible to make cuts of larger diameter and at angles previously impossible to pole mounted pruning devices.

This invention will also allow an operator aloft in a tree to reduce personal risk and time spent aloft by enabling him to reach many smaller branches that may require trimming from one safely belayed position.

According to this invention a very small and light chain-saw driven by a low voltage electric or other suitably powered motor is mounted at the top of a pole or series of connected poles. The angle and plane of operation of the saw in relation to the pole(s) is adjustable. The operation of the saw may be controlled by switches at the handgrip which is at the opposite end of the pole(s) from the saw blade. The Pole-Saw can be provided as a complete purpose-built kit or as an adaptation for existing sets of poles. The chain-saw may be replaced if required by a reciprocating blade or hedge clipper bar. The saw head may be fitted with 'dogs' to protect the mechanism and assist in control of the object being cut.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 shows a very small (e.g. 6-inch) bar chain-saw in position on a pole, with an operating handle; the motor in this example is mounted with the saw and is powered by a lead-acid type 12-volt battery.

Figure 2 shows a saw-head unit tilted in 2 different planes relative to the mounting-pole axis.

Figure 3 shows an example of an operating handle unit.

Figure 4 shows an example of a connection between 2 intermediate pole sections having in this case lockable threaded spigot and socket joints and internal power supply cable connections. The poles may be constructed of metal or of non-conductive material as required.

Referring to the drawings, the Pole-Saw comprises a motor driven sawhead (12) mounted on a lockable ball- or equivalent type of joint (19) on the end of a rigid pole assembly (13). The saw is operated by switches mounted on a handgrip (14) at the other end of the rigid pole assembly and power in this example is provided from a 12 volt lead-acid vehicletype battery (16) suitably connected through a circuit breaker (15).

The Pole-Saw is assembled to a length suitable for the task in hand and the saw-head (12) is offered up to a branch that requires lopping. A safety switch (23) is operated releasing the trigger lock so that the trigger (21) can be squeezed to allow electric current to the drive motor. The motor drives the saw which is used to cut the branch. When the branch has been cut the trigger is released and the saw stops.

If a drive motor is powered other than by electricity, the operating controls are still contained in the hand grip (14).

A power supply may be mounted on the Pole-Saw or be separate from it as indicated in Figure 1.

A drive motor may be mounted at any suitable position on the pole either with or remote from the saw head.

A folding or detachable anti-twist device, such as a rod at right angles to the pole(s) which will bear against the operator's upper forearm, may be fitted as required.

A chain saw-head may be fitted with a means of lubricating the chain as required whilst in use.

Claims

1. A powered pole-saw comprising a rigid pole assembly with a small power-driven chain-saw at one end and a handgrip with control switches at the other end.

2. Any powered pole-saw as claimed in Claim 1 which can be adapted to operate a reciprocating blade or hedge-clipper assembly in place of the chain-saw.

3. A powered pole-saw as claimed in Claims 1 and 2 wherein means are provided to securely adjust the plane of the cutting edges to different angles with respect to the pole axis.

4. Any powered pole-saw as claimed in any previous claim using electricity or internal combustion to drive its motor.

5. Any powered pole-saw as claimed in any previous claim which has its motor mounted at any position on the pole.

6. Any powered pole-saw as claimed in any previous claim wherein suitable means of lubricating the saw is provided on the pole-saw.

7. Any powered pole-saw as claimed in any previous claim wherein a braking system is provided to stop the cutting movement as required for safety or operating purposes.

8. Any powered pole-saw as claimed in any previous claim wherein an anti-twist device that is folding, removable or fixed is fitted, with the object of controlling rotational movement of the pole.