EP2039851A2

EP2039851A2 - A post driver

Info

Publication number: EP2039851A2
Application number: EP20080164831
Authority: EP
Inventors: Joseph Anthony Brennan; Michael Richard Brennan
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-09-20
Filing date: 2008-09-22
Publication date: 2009-03-25
Also published as: IE20080765A1; IES20080764A2

Abstract

The present invention is directed to a post driver comprising a support frame having a post driver unit mounted thereon, wherein, the post driver further comprises an articulated arm mounted on an opposing side of the support frame to the post driver unit. The advantage of using an articulated arm is that the articulated arm may operate in part as a counterweight to the post driver unit on the post driver. Furthermore, the articulated arm may be manoeuvred to alter the location of the counterweight on the post driver thus allowing the post driver to operate more efficiently and more safely on inclined surfaces. By having the articulated arm mounted on an opposing side to the post driver, the stability of the post driver is optimised. The articulated arm may be an excavator arm, and more preferably a back actor.

Description

Introduction

This invention relates to a post driver comprising a support frame having a post driver unit mounted thereon. In particular, the invention is related to post drivers which are designed to be transported by tractors, farm machinery and the like.
Post drivers are typically used in the erection of fencing. Prior to the advent of post driver, farmhands and labourers would have to manually insert each post of a fence into the ground. By inserting a plurality of posts into the ground at a predefined distances from each other, a screening element such as meshed wire, barbed wire or wooden boards is placed between the posts to form the fence. This was very labour intensive and time consuming. The advent of post drivers allowed users to insert an individual post into the ground without requiring too much manual involvement. The post drivers that were developed commonly comprised a post holding element which was struck repeatedly by a hammer element to drive a post held by the post holder into the ground.
One example of such a post driver is described in European Patent Application EP07114208 , filed by the applicant. The post driver described comprises a support frame, a mast mounted on the support frame, a post holder slidably mounted on the mast and a hammer slidably mounted on the mast above the post holder to urge the post holder downwards relative the mast and to drive a post held by the post holder into the ground. A counterweight is also provided on the support frame to stabilise the post driver during operation. The post driver is further provided with alignment means to ensure correct alignment of the post whilst it is being driven into the ground. The alignment of the post is achieved by tilting the mast of the post driver relative to the surface of the ground into which the post is being driven. The entire disclosure of EP07114208 , but in particular those parts relating to the construction of the post driver, is incorporated herein by way of reference.
One problem addressed in EP07114208 is that a post driver may be required to operate on a sloped surface. If a user wishes to drive the posts into the ground in a substantially vertical orientation, it is necessary to tilt the post driver unit relative to the support frame to arrange the mast, post holder and hammer into the substantially vertical orientation required. The post driver described in EP07114208 works well and does indeed solve this problem, however a stability issue arises when the post driver is operated on a relatively steep slope.
Under normal operation on a flat surface, the counterweight balances the post driver whilst the post driver unit is operating. When the post driver is required to work on an inclined surface, the counterweight will no longer be in an ideal position to balance the post driver unit. The mast, post holder and hammer of the post driver unit are tilted to drive the post in at an angle to the surface of the ground and the post driver unit will therefore exert different forces on the support frame. The counterweight will no longer be in the ideal position to counteract these forces. Thus, the counterweight may not be providing optimised stability to the post driver when the post driver is set on an inclined surface. This stability problem will hamper the efficient erection of fencing as the user of the post driver may have to lessen the force applied with each hammer stroke to account for the reduced stability of the post driver. The reduction in force of each hammer stroke will result in a longer construction time for the fencing. Moreover, the reduced stability will pose a safety hazard to the user of the post driver.
A separate problem with current post drivers is that the post drivers are specifically designed to only perform the task of driving posts into the ground. Many potential purchasers of post drivers are dissuaded from purchasing the post driver due to its limited functionality. This problem is known to impact on the commercial uptake of post drivers.
It is a goal of the present invention to provide a post driver apparatus that overcomes at least one of the above mentioned problems.

Statements of Invention

The present invention is directed to a post driver comprising a support frame having a post driver unit mounted thereon, wherein, the post driver further comprises an articulated stabilising arm mounted on the support frame, said articulated stabilising arm moveable between a plurality of stabilising positions within a predefined area to cause a change in the weight distribution of the post driver and allow the stability of the post driver to be altered.
In this way, the articulated arm may operate in part as a counterweight to the post driver unit on the post driver. Furthermore, the articulated arm may be manoeuvred to alter the location of the counterweight, provided for by the articulated arm, on the post driver thus allowing the post driver to operate more efficiently and more safely on inclined surfaces.
In a further embodiment, the articulated arm is mounted on an opposing side of the support frame to the post driver unit.
By having the articulated arm mounted on an opposing side to the post driver, the stability of the post driver is optimised. The weight distributed across the post driver is primarily grouped at two points: the point on the support frame where the post driver unit is mounted and the point on the support frame where the articulated arm is mounted. The weights of the post driver unit and the articulated arm are the main factors that influence the weight distribution and the stability of the post driver.
This is more stable than other known post drivers which do not have any adjustable counter weights and have the post driver unit mounted in line with the 3-point hitch.
Furthermore, by moving the articulated arm of the present invention, the position of this point of the weight distribution is altered to allows the stability of the post driver to be adjusted to different terrains, and more particularly to inclined surfaces.
In a further embodiment, the articulated arm is mounted on an opposing side of the support frame to the post driver unit.
In a further embodiment, means is provided for carrying a counterweight at an outer end of the articulated arm.
In a further embodiment, the post driver further comprises a counterweight detachably mounted on the support frame.
By having such a device, the counterweight may be detached from the support frame and may be carried by the excavator unit in a position remote from the support frame body thereby increasing the effectiveness of the counterweight. This will help to reduce the size and weight of counterweight required.
In a further embodiment, a plurality of pre-defined complementary mounting points are provided on the support frame with each of which the counterweight is detachably engagable.
This is done in response to whether the post driver is in transit, or, whether one of either the articulated arm or post driver unit is being used.
In a further embodiment, the counterweight is detachably engagable with a free end of the articulated arm.
In a further embodiment, the support frame comprises outriggers to further stabilise the assembly during use.
In a further embodiment, the articulated arm has a ground engaging plate at a free end of the arm to enable the arm to act as an outrigger. This will help to reduce the amount of counterweights that must be provided on the post driver as the articulated arm can act as an additional outrigger.
In a further embodiment, means is provided for mounting a tool at an outer free end of the articulated arm.
In a further embodiment, the articulated arm comprises an elongate excavator arm which is mounted on the support frame by an articulated joint.
By specifying the articulated arm as an excavator arm, all of the advantages of the articulated arm such as adjustable stability points are maintained and there is the additional advantage of having an excavator to assist with construction of the fencing. Up to now, it has been necessary to supply an independent excavator arm by way of a separate excavator or mechanical digger. The excavator arm is very useful to assist in constructing a fence by either digging holes or trenches, or by preparing a plot of land for fencing by moving soil to flatten the land or create a raised platform of soil. By adding the advantages associated with an excavator arm, the post driver of the present invention becomes a less specialised piece of machinery and is therefore more attractive to potential purchasers as the post driver provides this increased functionality.
In a further embodiment, the elongate excavator arm is a back actor. This is seen as a particularly advantageous embodiment of the invention.
In a further embodiment, the articulated arm is rotatably mounted on a slidable carriage mounted on the support frame. The slidable carriage will allow the articulated arm greater movement and hence greater adjustment of the stability point.
In a further embodiment, the elongate excavator arm comprises a digging bucket at a free end of the elongate excavator arm.
In addition to the earth moving capabilities of the digging bucket, a major advantage of this embodiment is that the digging bucket may also be used to provide various improvements to the stability of the post driver. Counterweights may be placed and secured within the bucket and lifted outwardly from the post driver to provide extra weight to stabilise the post driver. The moment resulting from the remote placement of the counterweights from the support frame will increase the effectiveness of the counterweights in comparison to simply connecting the counterweights directly to the support frame. This could allow for lighter counterweights to be used, which is advantageous for numerous reasons such as transportation and safety. Alternatively, the excavator arm may dig partially into the ground to act as an anchored outrigger.
In a further embodiment, the tool comprises a digging bucket, a grappling claw, an auger screw, a breaker or hoe ram.
Similarly to above, a grappler may secure counterweights in its claws and hold these counterweights remotely from the support frame of the post driver. Alternatively, the grappler may grab hold of a nearby object such as a tree or sturdy wall to act as an anchored outrigger. The auger screw may screw itself into the ground to enable the excavator arm to act as an anchored outrigger. The breaker or hoe ram will assist with the construction of the fencing.
In a further embodiment, the post driver unit comprises a mast having a post holder slidably mounted on the mast and moveable between a raised position and a lowered position; the post driver unit further comprising means slidably mounted on the mast above the post holder for urging the post holder from the raised position to the lowered position.
In a further embodiment, the post driver unit further comprises a striker plate which is slidably mounted on the mast intermediate the post holder and the means for urging the post holder from the raised position to the lowered position.
In a further embodiment, the mast is pivotably mounted on the support frame to allow posts to be inserted into the ground at varying angles relative to the surface of the ground, and, the post driver unit further comprises alignment means to automatically tilt the mast in response to alignment sensors.
In a further embodiment, the alignment sensors are mercury tilt sensors or electronic lilt sensors.
In a further embodiment, the post holder comprises a post receiving socket which holds a post by a force-fit.
In a further embodiment, the post receiving socket is demountably connected to the post holder.
In a further embodiment, operation of the articulated arm and the post driver unit is controlled by a system of hydraulic rams, each of the hydraulic rams comprises at least one valve to control the operation of said ram, a solenoid is operably connected to each valve and a remote control unit is operable to control each solenoid by means of a wireless signal.
This is seen as particularly advantageous as the remote control unit will allow operation of the post driver by an operator located remote from the post driver. This will significantly reduce the possibility of the operator being injured while operating the post driver. Furthermore, this will allow greater flexibility to the operator in the areas in which the post driver may be used and finally it is envisaged that this will allow for an improved fence to be provided as the operator will be able to align the posts with greater accuracy by being able to view the fence from a remote location as the posts are being driven into the ground.
In a further embodiment, the assembly further comprises a conventional 3-point hitch to allow the assembly to be transported by a vehicle having a complementary 3-point linkage.

Detailed Description of the Invention

The invention will be more clearly understood by the following description of some embodiments thereof, given by way of example only with reference to the accompanying drawings, in which:

Fig. 1 is a perspective view of a post driver according to the present invention;
Fig. 2 is a further perspective view of the post driver of Fig. 1 with the articulated arm retracted;
Fig. 3 is a further perspective view of the post driver of Fig.1 with the articulated arm extended;
Fig. 4 is a rear side perspective view of the post driver of Fig. 3;
Fig. 5 is a side view of the post driver of Fig. 3;
Fig. 6 is a front side view of a further embodiment of the post driver of the present invention;
Fig. 7 is a rear perspective view of the post driver of Fig. 6;
Fig. 8 is diagrammatic representation of a remote control unit for use with the post driver of the present invention;
Fig. 9 is a side view of the post driver of the present invention with the articulated arm acting as an additional outrigger; and,
Fig. 10 is perspective view of the post driver of the present invention with the articulated arm mounting an auger screw.

Referring to the drawings and initially to Figs. 1-5 thereof, there is provided a post driver indicated generally by the reference numeral 100. The post driver 100 comprises a support frame indicated generally by reference numeral 102 having a post driver unit indicated generally by reference numeral 104 and an articulated arm indicated generally by reference numeral 106 mounted thereon. The articulated arm 106 and the post driver unit 104 are mounted on substantially opposing sides of the support frame 102. In a further embodiment (not shown), the articulated arm 106 may be mounted in close proximity to the post driver unit 104, with an appropriate counterweight on the opposing side. However, it is preferable to use the articulated arm 106 in part as a counterweight to the post driver unit 104. Support legs 108 may be extended downwardly and/or outwardly and downwardly from the support frame 102 to act as stabilising supports and outriggers for the post driver 100. A detachable counterweight 110 is mounted on the support frame 102. In further embodiments, the counterweight may be secured to the support frame at a number of predefined connection points to allow the user of the post driver 100 to redistribute the weight of the post driver 100 depending on whether the post driver is in transit, or one of the post driver unit 104 or articulated arm 106 is in use. A control panel 112 is also mounted on the support frame 102. The control panel 112 may be used to control the post driver unit 104 and/or the articulated arm 106.
The post driver unit 104 comprises an extendable mast section 114 that is pivotably connected to the support frame 102. A post holder 116 as is known in the art is slidably mounted on the mast section 104. The post holder 116 may comprise a detachable post receiving socket which receives and secures the posts. Differently sized post receiving sockets may be used to hold differently sized posts. In a preferable embodiment, the post holder 116 comprises means to rotate and twist a held post (not shown) to assist with inserting the post into the ground.
A hammer 118 is slidably mounted on the mast 114 above the post holder 116. A lifting line (not shown) is connected to the hammer 118. The lifting line is connected to an actuating means (not shown) via a pulley 120. The actuating means raises the hammer 118 to a predetermined height from the post holder 116 and releases the hammer 118 to allow the hammer 118 to fall under gravity. The hammer 118 strikes the post holder 116 and drives the held post into the ground. It is also known to alternatively use a ram to directly raise and lower the hammer 118 relative to the post holder 116.
A lateral tilting ram 122 is connected intermediate the support frame 102 and the mast 114 of the post driver unit 104. The lateral tilting ram 122 can tilt the post driver unit 104 relative to the support frame 102 to allow a post to be driven into an inclined slope in a vertical orientation. The lateral tilting ram 122 is operable to tilt the post driver unit 104 in a lateral direction relative to the support frame 102.
The articulated arm 106 is mounted to the support frame by an articulated joint 124. The articulated arm 106 comprises a boom 126 hingedly connected to a dipperstick 128 which in turn is hingedly connected to a digging bucket 130. In further embodiments, the articulated arm 106 may only comprise a single boom having means for attaching a digger bucket 130, grappler, auger screw, pincer or counterweight at the free end. Furthermore, the articulated arm 106 may be mounted on a slidable carriage (not shown) which is mounted on the support frame 102. A boom ram 200 is connected intermediate the boom 126 and the dipperstick 128, and a dipperstick ram 202 is connected intermediate the dipperstick 128 and the digging bucket 130.
As can be seen particularly in Fig. 4, the post driver 100 comprises a 3-point hitching mechanism indicated generally by reference numeral 400. This 3-point hitching mechanism 400 comprises a pair of lower hitching points 402 and an upper hitching point 404. The lower hitching points are connected directly to the support frame 102 and the upper hitching point is connected to the support frame 102 via a transverse tilting ram 406. The lower hitching points 402 allow the post driver to be rotably connected to a tractor (not shown) and the transverse tilting ram 406 may be then employed to tilt the post driver 102 in a transverse, orthogonal direction to the lateral tilting ram 122. The adjustable support legs 108, the lateral titling ram 122 and the transverse tilting ram 406 may combine to allow for tilting and adjustment of the post driver unit 104 and in particular the mast 114 in all directions. The post driver 100 may therefore be employed on all terrains.
Referring particularly to Fig. 5, the post driver 100 is seen to comprise a safety shield 500 that is mounted along a side of the mast 114. The safety shield 500 is positioned between the control panel 112 and the post holder 116/hammer 118 portion of the post driver unit 104. A user standing in proximity to the control panel 112 will be protected from any wood splinters or the like which may be expelled by the post holder 116 and/or the hammer 118.
Referring to Figs. 6 and 7, wherein like parts previously described have been assigned the same reference numerals, a post driver is provided indicated generally by reference numeral 600. The post driver 600 comprises a striker plate 602 mounted on the mast 114 between the hammer 118 and the post holder 116.
With reference to Fig. 8, wherein like parts previously described have been assigned the same reference numerals, a portion of a remote control system indicated generally by reference numeral 800 is provided. The remote control system 800 comprises the control panel 112 connected to a receiver 802. A transmitter 804 comprising control buttons 806 and an antenna 808 sends a wireless signal 810 from the antenna 808 in response to inputs made by a user via the control buttons 806. The wireless signal 810 is received by the receiver 802. Valves 812 in the control panel 112 are controlled by means of manually-operated levers 814 or by means of solenoids 816. The valves 812 are connected to a hydraulic system (not shown) which is used to control the various rams associated with the post driver 100, 600.
In use, a user will mount the post driver 100, 600 onto a tractor (not shown) by means of the 3-point hitching mechanism 400 on the rear of the tractor. The post driver 100, 600 is transported to the work area and the support legs 108 of the post driver 100, 600 are lowered into position. The post driver unit 104 is tilted and adjusted to the desired angle, and the articulated arm 106 is manoeuvred into the most ideal position to provide maximum stability to the post driver 100, 600. The post driver 100, 600 is operated in the normal manner thereafter. Automatic tilting sensors such as mercury sensors or electronic tilt sensors may be used to align the mast 114 to a desired angle. Sensors in the post driver 100, 600 may be used to measure the weight exerted at each stability point of the stability triangle, and an approximate "ideal" position for the articulated arm 106 may be calculated, and displayed to a user. With reference to Fig. 9, the articulated arm 106 is shown used as an additional outrigger or support leg for the post driver 100, 600.
With reference to Fig. 10, wherein like parts previously described have been assigned the same reference numeral, a post driver indicated generally by reference numeral 1000 is provided. The articulated arm 106 of the post driver 1000 is mounted with an auger screw 1002 as opposed to a digging bucket 130. Similarly, a grappler (not shown) or a pincer (not shown) or a further counterweight (not shown) may be mounted at the end of the articulated arm 106.
It will be understood that various other uses of the articulated arm 106 would be apparent to those skilled in the art and the uses and advantages are not limited to those described herein. For example, the digger bucket 130 may be useful in refilling holes previously made by posts that were not in alignment with other posts. Furthermore, different attachments such as a spike, a fork or shovel head may be provided instead of the digging bucket 130.
Hydraulic power is the preferred mode of powering the equipment although it will be understood that other methods of powering the equipment, such as electrical and pneumatic means, could be utilised without departing from the scope of the present invention. For reasons of clarity, many of the hydraulic cables have been removed from the drawings but their implementation would be understood by one skilled in the art.
Furthermore, it is envisaged that a power take off from the tractor could be used or alternatively a separate power supply on the post driver 100, 600, 1000 could be used to operate the hydraulics system and in turn the articulated arm 106 and the post driver unit 104.
It will be understood that the detachable counterweight 110 may be detached and mounted in the digging bucket 130 of the articulated arm 106. In a further embodiment (not shown), a counterweight is fixedly mounted on the support frame 102 by a welded connection or the like.
In a further embodiment, the articulated arm 106 may swivel about relative to the support frame 102.
In the specification the terms "comprise, comprises, comprised and comprising" or any variation thereof and the terms "include, includes, included and including" or any variation thereof are considered to be totally interchangeable and they should all be afforded the widest possible interpretation and vice versa.
The invention is not limited to the embodiments hereinbefore described which may be varied in both construction and detail with the scope of the appended claims.

Claims

A post driver comprising a support frame having a post driver unit mounted thereon, characterised in that, the post driver further comprises an articulated stabilising arm mounted on the support frame, said articulated stabilising arm moveable between a plurality of stabilising positions within a predefined area to cause a change in the weight distribution of the post driver and allow the stability of the post driver to be altered.
A post driver as claimed in claim 1, wherein, the articulated arm is mounted on an opposing side of the support frame to the post driver unit.
A post driver as claimed in claim 1 or claim 2, wherein, means is provided for carrying a counterweight at an outer end of the articulated arm.
A post driver as claimed in any preceding claim, wherein, the post driver further comprises a counterweight detachably mounted on the support frame.
A post driver as claimed in claim 4, wherein, a plurality of pre-defined complementary mounting points are provided on the support frame with each of which the counterweight is detachably engagable.
A post driver as claimed in claims 4 or 5, wherein, the counterweight is detachably engagable with a free end of the articulated arm.
A post driver as claimed in any preceding claim, wherein, the articulated arm has a ground engaging plate at a free end of the arm to enable the arm to act as an outrigger.
A post driver as claimed in any preceding claim, wherein, means is provided for mounting a tool at an outer free end of the articulated arm.
A post driver as claimed in any preceding claim, wherein, the articulated arm comprises an elongate excavator arm which is mounted on the support frame by an articulated joint.
A post driver as claimed in claim 9, wherein, the elongate excavator arm is a back actor.
A post driver as claimed in any preceding claim, wherein, the articulated arm is rotatably mounted on a slidable carriage mounted on the support frame.
A post driver as claimed in claim 8, wherein, the tool comprises a digging bucket, a grappling claw, an auger screw, a breaker or hoe ram.
A post driver as claimed in any preceding claim, wherein, the mast is pivotably mounted on the support frame to allow posts to be inserted into the ground at varying angles relative to the surface of the ground, and, the post driver unit further comprises alignment means to automatically tilt the mast in response to alignment sensors.
A post driver as claimed in claim 13, wherein, the alignment sensors are mercury tilt sensors or electronic lilt sensors.
A post driver as claimed in any preceding claim, wherein, operation of the articulated arm and the post driver unit is controlled by a system of hydraulic rams, each of the hydraulic rams comprises at least one valve to control the operation of said ram, a solenoid is operably connected to each valve and a remote control unit is operable to control each solenoid by means of a wireless signal.