GB2354788A

GB2354788A - Apparatus for driving posts into the ground

Info

Publication number: GB2354788A
Application number: GB9923268A
Authority: GB
Inventors: Keith Frank Meade; John Uphill
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-10-02
Filing date: 1999-10-02
Publication date: 2001-04-04
Also published as: GB9923268D0

Abstract

An apparatus (10) for driving a post (42) into the ground, comprises: a tube (12) for use in a generally vertically-extending orientation such that an upper end of a post to be driven projects into an open lower end of the tube; a weight (16) slidable inside the tube; and a mechanism (28,30,38) for repeatedly raising the weight up the tube and then letting the weight drop down the tube so as to impact the upper end of the post. By enclosing the weight in the tube, it is difficult for somebody to put their hand in the path of the weight. The mechanism for raising and dropping the weight may include a cable or rope (38) attached to the weight and extending upwardly through the tube. An abutment (18) is mounted in the lower end of the tube and arranged to engage the weight to prevent the weight escaping from the lower end of the tube in the case where the rope breaks or comes loose.

Description

2354788 TITLE Apparatus For Driving Posts Into The Ground

DESCRIPTION

This invention relates to apparatus for driving posts into the ground.

A simple way of driving a post into the ground is to hit the top of it repeatedly with a harnmer or the back of an axe. This can be hard work. Furthermore, in the case of a wooden post, if it is not hit square and true, the post is likely to split or splinter. Also, until the post has "started", it is necessary to steady it, and this is usually done by hand. If the hammer misses, while the post is being steadied, nasty and painful injuries can be caused.

A safer way of driving a post into the ground manually employs a driving tool comprising an upright tube with an open lower end, a closed upper end, and a pair of handles on the outside. The tube is placed over the top of the post and then is repeatedly raised and allowed to drop so that the inside of the closed upper end of the tube repeatedly strikes the top of the post to drive it into the ground. Using such a driving tool is, however, still hard work.

It is also known to provide an attachment for an excavator, tractor or the like, comprising a vertical slide along which a heavy weight can run, and a mechanism for repeatedly raising the weight up the slide and then letting it drop down the slide so as to impact the upper end of the post positioned near the bottom of the slide. If somebody should put their hand in the path of the weight, they are likely to suffer a serious injury. Also, the mechanism includes a cable or rope which is attached to the weight and which can, in time, break or come loose, whereupon the weight can fall to the ground causing injury to anybody who may be in its way.

In accordance with the present invention, there is provided an apparatus for driving a post into the ground, comprising: a tube for use in a generally vertically-extending orientation such that an upper end of a post to be driven projects into an open lower end of the tube, a weight slidable inside the tube, and a mechanism for repeatedly raising the weight up the tube and then letting the weight drop down the tube so as to impact the upper end of the post. By enclosing the weight in a tube, it is far more difficult for somebody to put their hand in the path of the weight.

Preferably, the apparatus further includes means for limiting the movement of the weight so that the weight cannot escape from the lower end of the tube. For example, there may be an abutment mounted in the lower end of the tube and arranged to engage the weight to prevent the weight escaping from the lower end of the tube. This is particularly useful in the case where the mechanism for raising and dropping the weight includes a cable or rope which is attached to the weight and which might, in time, break or come loose.

A specific embodiment of the present invention will now be described, purely by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a sectioned side view of a post driving apparatus of one embodiment of the invention in a first position; and Figure 2 is a side view of the apparatus of Figure 1, but in a second position, and also showing a post.

Referring to the drawings, a post driving apparatus 10 includes a circular-cylindrical steel tube 12 which is used in a generally vertical configuration and which has a bracket 14 welded to it for mounting the apparatus 10 onto the jib of a "mini- digger" or the like so that the mini-digger can hold the tube 12 in a desired position for operation. A cylindrical steel weight 16 is a loose sliding fit in the tube 12, and an internal flange 18 is welded to the lower end of the tube 12 to prevent the weight 16 escaping from the lower end of the tube 12. A generally semi-circular plate 20 is fitted to the upper end of the tube 12 so as to half-close that end of the tube. The semi-circular plate 20 may be welded to the tube 12, but preferably is removably mounted on it. At least one upright bracket 22 is welded to the semi- circular plate 20 to provide a mounting for a pulley 24. At least one ftirther outwardly -projecting bracket 26 is welded to the outside of the tube 12 to provide a mounting for an L-shaped crank 28 and a hydraulic ram 30. The shorter arm of the crank 28 is pivotally mounted adjacent its distal end to the bracket 26. The hydraulic ram 30 acts between the bracket 26 and the root of the crank 28 and has a union 32 for connection to the hydraulic system of the mini-digger so that the ram 30 can be extended under hydraulic pressure and then rapidly allowed to contract. The longer arm of the crank 28 projects upwardly and has a pulley 34 mounted adjacent its distal end. The top of the weight 16 has an eye 36 to which is attached one end of a rope 38. The rope 38 extends vertically up the tube 12, around the pulley 24, around the pulley 34 and has its other end attached to an eye 40 formed in the bracket 22.

In the position shown in Figure 1, the weight 16 is resting on the flange 18 at the bottom of the tube 12, the longer arm of the crank 28 is generally vertical, and there is little or no slack in the rope 38. In order to drive a post 42 into the ground, the ram 30 is extended SO as to pivot the longer arm of the crank 28 away from the tube 12 and thus draw the weight 16 up to the top of the tube 12, as shown in Figure 2. The post 42 is held in position ready for driving by a banksman, and the mini-digger operator then positions the tube 12 over the post 42 5 so that the post projects up into the lower third or quarter of the tube 12, as shown in Figure 2. The banksman can then stand clear. The mini-digger operator then operates the hydraulic system so that the hydraulic ram 30 is repeatedly extended and then allowed to contract rapidly, and therefore the weight 16 is repeatedly raised up the tube 12 and then dropped onto the top of the post 42 so as to drive the post 42 into the ground. If need be, the apparatus 12 as a whole can be lowered, by lowering the jib of the mini-digger, so that the post can be driven to a sufficient depth into the ground.

It will be appreciated from the foregoing that the banksman can stand clear of the apparatus 12 before the apparatus 12 commences to drive the post 42 into the ground, and furthermore that, if the rope 38 should break before the banksman has stood clear, the flange 18 will prevent the weight 16 falling from the bottom of the tube 12 and injuring the banksman. It should be noted that, because the wall of the tube 12 is closed, the risk of accidental injury, by somebody putting their fingers where they should not, is reduced.

It will also be appreciated that the apparatus can be used without a banksman. In this case, the mini-digger operator would position the apparatus so that the tube 12 is cVrectly above the place where the post 42 is to be driven and so that the height of the bottom of the tube 12 above the ground is slightly less than the length of the post 42. The operator would then insert the top of the post 42 into the tube 12 with the post 42 canted over slightly. The operator would then straighten the post and rest its lower end in position. The operator would then return to the mini-digger and lower the apparatus 12 so that the post 42 projects further into the tube 12, and then commence the driving operation described above.

It should be noted that the embodiment of the invention has been described above purely by way of example and that many modifications and developments may be made thereto within the scope of the present invention.

Claims

I An apparatus for driving a post into the ground, comprising:

a tube for use in a generally vertically-extending orientation such that an upper end of a post to be driven projects into an open lower end of the tube; a weight slidable inside the tube; and a mechanism for repeatedly raising the weight up the tube and then letting the weight drop down the tube so as to impact the upper end of the post.
2. An apparatus as claimed in claim 1, further including means for limiting the movement of the weight so that the weight cannot escape from the lower end of the tube.
3. An apparatus as claimed in claim 2, wherein the limiting means comprises an abutment mounted in the lower end of the tube and arranged to engage the weight to prevent the weight escaping from the lower end of the tube.
4. An apparatus as claimed in any preceding claim, wherein the mechanism for raising and dropping the weight includes a cable or rope attached to the weight and extending upwardly through the tube, and a drive for pulling and releasing the cable or rope.
5. An apparatus for driving a post into the ground, substantially as described with reference to the drawings.