AU717695B2 - Guide post driver - Google Patents

Description

AUSTRALIA

Patents Act 1990 PETER GEOFFREY TURNER, DENNIS WYNWOOD

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: Guide Post Driver The following statement is a full description of this invention including the best method of performing it known to us:c r Guide post driver Field of the Invention The present invention relates to a post driver for driving roadside posts and similar articles into the ground. More particularly the present invention relates to improved post drivers that can be used, among other things, to remove posts as well as to drive them and/or to drive posts that might otherwise be damaged when being driven into the ground.

Background Art It is well known to drive star pickets and other posts using a post driver comprising a heavy tube closed at one end. The tube is placed over the post to be driven. Manual raising and forceful dropping of the tube serves to drive the post into the ground. Typically the driver will be provided with manually graspable handles to facilitate the raising and dropping of the driver, however if the cross sectional area of the tube is small 15 enough it is possible for a user to merely grasp the tube itself.

Disclosure of the Invention According to a first aspect, the present invention consists in a post driver provided with manually grippable means allowing the driver to be manually raised and lowered in driving a post into the ground, the post driver being characterised in that elongate guide means are provided inside the driver adapted to closely surround the post or parts thereof and to maintain the relative lateral positions of the driver and the post during S•driving of the post.

In a preferred embodiment, the post driver includes a cap member 25 adapted to be removably positioned on the top of a post and a driving member including a tubular member having a closed end and an open end and slidable on the cap member so that a driving force can be applied to a post through the cap member, the elongate guide means being provided inside the cap member.

The cap member can be rectangular in cross-section and be provided with a pair of slides down each inside surface of each of two opposed side walls, the slides defining between them the guide means to receive and guide the edges of a steel post.

In a further preferred embodimnent, the post driver further comprises an elongate member having a free end, the elongate member being slidably ,-iAAZ. attached to the tubular member such that it may slide between a first position in which its free end is distal the open end of the tubular member and a second position in which the free end lies adjacent the open end of the tubular member, the elongate member being provided at its free end with an engagement means adapted to be engaged with an aperture in a post such that upward movement of the post driver may be transmitted to a post to urge it upwardly relative to ground into which the post has been drive.

The elongate member is preferably a rod of steel or some similar material having at its free end a hook or other engagement means for connection with an aperture in a post that is to be removed from the ground.

The rod is preferably slidable in a short sleeve welded or otherwise attached to the outside of the post driver adjacent to its open end, the rod being slidable within the sleeve. The rod is preferably provided at its end distal to the engagement means with a boss or lug that will be struck by the upper end of the sleeve as the post driver is lifted upwardly. The upward force applied to the rod is transmitted to a post to be lifted from the ground by engagement of the engagement means on the lower end of the rod with an aperture in the post.

The sliding rod might get in the way during the use of the driver to drive posts into the ground unless it can be parked out of the way during such use of the driver. For this reason the boss or lug on the upper end of the rod is preferably provided with means to allow it to be held in position alongside the tubular body of the post driver when the rod is not in use.

S• Preferably the boss or lug includes a laterally extending arm that can be swung over the upper, closed, end of the tubular body and engaged with 25 some complementary locking device to keep the rod in position alongside the tubular body of the post driver when required.

In preferred embodiments of the present invention the cap is rectangular in cross-section and is provided with a pair of slides down each inside surface of each of two opposed sidewalls. The slides define between them a guide path to receive the edges of a steel post. The presence of the slides means that the cap may be positioned positively on the top of a post to be driven into the ground. This avoids damage to the upper end of the post during the driving process. It also avoids damage to reflectors and like articles already attached to the upper end of a post to be driven into the ground.

Preferred Embodiment of the Invention A preferred embodiment of the invention is hereinafter described with reference to the accompanying drawings in which:- Figure 1 is a side elevational view of a post driver according to the present invention, Figure 2 is a front elevational view of the post driver of Figure 1, Figure 3 is a rear elevational view of the post driver of Figure 1, Figure 4 is a cross sectional view along IV-IV of Figure 2, Figure 5 is a plan view of the post driver of Figure 1, Figure 6 is a side elevational view of a cap member for use with the post driver of Figure 1, Figure 7 is a front elevational view of the cap member of Figure 6, Figure 8 is a rear elevational view of the cap member of Figure 6, Figure 9 is an underneath plan view of the cap member of Figure 6 15 showing the position of a post if the cap were in use, Figure 10 is a sectional view along X-X of Figure 7, Figure 11 is a plan view of the cap member of Figure 6, and Figure 12 is perspective view of a post of the type adapted to be driven by the post driver of Figure 1 incorporating the cap of Figure 6.

The post driver 10 comprises a cap 11 and a tubular body 12. The cap is designed to fit over a post 13, as seen in Figure 12 which comprises a rolled steel section having a central web 14, a pair of angled flanges "I flanking the central section 14, and a pair of lateral flanges 16 that flank the angled flanges 15 and lie in a plane parallel to that of the central web 14.

25 The cap 11 comprises a rectangular section steel tube 17 closed at one end by a plate 18. On the inside surface of each of two side walls 19 of the tube 17 is a slide member 21. Each slide member 21 has an elongate slot on its inwardly facing surface adapted to receive one of the lateral flanges 16 of a post of the type of Figure 12. Each of the slides 21; which are formed of high density polypropylene, is attached to the associated side walls by screws 22.

The tubular body 12 is formed of steel and is closed by a plate 23 at one end. The size and shape of the interior of the tubular body 12 is such that it will comfortably receive the cap 11. A D-shaped handle 24 is attached to the exterior of each of two side walls 25 of the tube 12 to allow a user to grip the post driver 10 in use and to raise and drop it conveniently. Although the embodiment of the present invention described includes the cap 11 carrying the slide members 21, it would be quite possible, and in some cases advantageous, to eliminate the cap and position the slide members 21 in the tubular body 12.

An elongate rod 26 is provided on the outside of the tubular body 12.

The rod 26 is adapted to slide longitudinally of the tubular body 12 through a sleeve 27 welded onto the exterior of one of the side walls 25 of the tubular body 12. The sleeve 27 is supported on the tubular body 12 not only by being itself welded to the tubular body 12 but also by a pair of supporting straps 28 welded to the sleeve 27 and the tubular body 12. The rod 26 has a turned over end portion 29 at its lower end and a boss 31 at its upper end.

The boss 31 has a radially extending flange 32 projecting from it in a plane 600 from the plane of the end portion 29 of the tubular body 12.

The upper surface of the plate 23 at the upper end of the tubular body 12 is provided with a pair of upstanding tabs 33 lying in planes at 6(f to one 15 another. The tabs are sited on the plate 23 at the mid-point of its side adjacent to the sidewall of the tubular body 12 carrying the sleeve 27. The flange 32 and each of the tabs 33 are provided with transverse holes so that when the flange 32 is aligned with either of the tabs the respective holes are in alignment and a C-clip may be inserted through those holes to secure the flange 23, and the rod 26 to which it is connected, in a desired orientation.

In use the post driver 10 is carried to a job with the cap 11 slid into the inside of the tubular body 12. The rod 26 will lie in its retracted position alongside the tubular body 12 and with the flange 32 lying adjacent one of the tabs 33 such that the end portion 29 of the rod 26 projects across the 25 mouth of the tubular body 12. This positioning of the end portion 29 of the rod 26 prevents the cap 11 sliding out of the tubular body 12. The rod 26 is held securely in the desired orientation by C-clip 34 extending through the aligned holes in the flange 32 and the respective tab 33.

When it is desired to drive a post 13 the cap 11 is removed from the tubular body 12 and slid over the upper end of the post 13. The rod is secured in its retracted position alongside the tubular body 12 but with the rod rotated so that the flange 32 lies adjacent the other of the tabs 33. This ensures that the end portion 29 of the rod 26 will not interfere with the movement of the tubular body 12 relative to the cap 11 and the post 13. The C-clip 34 is removed to allow the rotation of the rod 26 and then inserted into Sthe holes in the flange 32 and the hole in the other of the tabs 33. The 6 tubular body is then manually raised using handles 24 and is brought down sharply to impart a driving force to the post 13.

If it is desired to remove a post 13 that has already been driven into the ground the cap 11 is placed over the post 13. The tubular body 12 is again slid over the cap 11 and the post 13. The flange 32 on the rod 26 is turned so that it is free of the plate 23 and can be slid into its extended position in which it projects substantially beyond the lower end of the tubular body 12.

The upturned end portion 29 of the rod 26 is then engaged with an aperture in the post 13. If desired the C-clip hay be inserted through a hole (not shown) on the tip of the end portion 29 to prevent the rod 26 from being inadvertently dislodged from the hole 35. If the tubular body 12 is now raised sharply the tubular body 12 will move upwardly relative to the rod 26 and the sleeve 27 will strike the boss 31. This in turn will transmit an .e upward force through the rod 26 to the post 13. Eventually the post will be dislodged from the ground by the upward forces applied to it.

It will be appreciated by persons skilled in the art that numerous ••go variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

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Claims (7)

1. A post driver provided with manually grippable means allowing the driver to be manually raised and lowered in driving a post into the ground, the post driver being characterised in that elongate guide means are provided inside the driver adapted to closely surround the post or parts thereof and to maintain the relative lateral positions of the driver and the post during driving of the post.

2. A post driver as claimed in claim 1 in which the post driver includes a cap member adapted to be removably positioned on the top of a post and a driving member including a tubular member having a closed end and an open end and slidable on the cap member so that a driving force can be applied to a post through the cap member, the elongate guide means being provided inside the cap member.

3. A post driver as claimed in claim 2 in which the cap member is 15 rectangular in cross-section and is provided with a pair of slides down each inside surface of each of two opposed sidewalls, the slides define between them the guide means to receive and guide the edges of a steel post. S*4. A post driver as claimed in claims 2 or 3 further comprising an elongate member having a free end, the elongate member being slidably attached to the tubular member such that it may slide between a first 'position in which its free end is distal the open end of the tubular member and a second position in which the free end lies adjacent the open end of the """tubular member, the elongate member being provided at its free end with an engagement means adapted to be engaged with an aperture in a post such that upward movement of the post driver may be transmitted to a post to urge it upwardly relative to ground into which the post has been driven. A post driver as claimed in claim 4 in which the elongate member is a rod of steel or some similar material having at its free end a hook or other engagement means for connection with an aperture in a post that is to be removed from the ground.

6. A post driver as claimed in claims 4 or 5 in which the elongate member is slidable within a sleeve welded or otherwise attached to the outside of the tubular member adjacent to its open end.

7. A post driver as claimed in any one of claims 4 to 6 in which the elongate member is provided at its end distal to the engagement means with 8 a boss or lug that will be struck by the upper end of the sleeve as the post driver is lifted upwardly.

8. A post driver as claimed in claim 7 in which the boss or lug on the upper end of the elongate member is provided with means to allow the elongate member to be held in position alongside the tubular member of the post driver when the elongate member is not in use.

9. A post driver as claimed in claim 7 or claim 8 in which the boss or lug includes a laterally extending arm that can be swung over the upper, closed, end of the tubular body and engaged with a complementary locking device to keep the elongate member in position alongside the tubular member of the post driver when the elongate member is not in use. A post driver substantially as hereinbefore described with reference to Figures 1 to 11 of the accompanying drawings. Dated this nineteenth day of January 2000 PETER GEOFFREY TURNER, and DENNIS WYNWOOD Patent Attorneys for the Applicant: 00-660 F.B. RICE CO. C