WO1998006249A1

WO1998006249A1 - Improvements to ground penetrating implements

Info

Publication number: WO1998006249A1
Application number: PCT/GB1997/002145
Authority: WO
Inventors: John Michael Claxton
Original assignee: John Michael Claxton
Priority date: 1996-08-13
Filing date: 1997-08-11
Publication date: 1998-02-19
Also published as: AU3857497A

Abstract

An attachment for a foot-driven, ground penetrating implement such as a spade, comprising a foot pad (18), preferably faced with a resilient layer (20) and means such as an underside channel (15) by means of which the foot pad can be securely fixed to the top edge of the ground penetrating portion of the implement, as by means of screws (7) extending through the walls (8) of the channel.

Description

Improvements to Ground Penetrating Implements

This invention relates to improvements to ground penetrating implements, in particular exemplified by ground penetrating implements used in the garden.

Conventional ground penetrating implements generally referenced 10 in Figure 1 such as spades, forks, "lawn edgers" and the like usually comprise a blade 1 with an upper edge, herein termed bar 2, neck 3, shaft 4 and handle 5, where for simplicity the term "blade" is used to designate the ground penetrating portion of the implement.

When in use the ground penetrating portion of the implement 10 is usually a substantial portion, if not the entirety, of the blade 1. As the ground may be compact, dry with obstacles such as stones dispersed within it, the ground engaging edge, herein termed bar 6, of the implement needs to be thick enough to withstand damage from ground impact and robust enough to withstand the torque forces experienced when the implement is in use.

The advent of modern materials, be it laminates, alloys etc., has meant that the ground engaging bar 6 of the blade 1 of suh ground penetrating implements can be relatively thin.

The thin nature of the ground engaging bar 6 has positive advantages for anyone using the implement 10 as the force per unit area exerted on tiie ground during the implement's 10 normal use is maximised if the bar 6 is as thin as is practically possible.

Slightly curving the blade 1 also enhances the structural strength of the blade 1, increasing the amount of torque that the blade 1 can cope with, without damage. Through both the design of the blade and the nature of the materials used in the construction of the blade 1, the cross-sectional area of the bar 2, blade 1 and bar 6 in practical terms is substantially the same.

In use, such implements 10 are held by the user by the handle 5 and shaft 4, the arch of the user's foot being placed onto the bar 2 where pressure is applied to aid the penetration of the bar 6 into the ground.

During the professional use of such implements 10, purpose built footwear is usually supplied to the user of such an implement 10. This footwear is usually thick soled to protect the wearer's foot from damage caused by the repeated downward applied pressure of uie foot onto the bar 2 to affect ground penetration of the implement 10.

However, much of the non-professional use of such implements 10 carried out by, for example, DIY garden enthusiasts is performed with non-purpose built footwear. More often than not, the preferred footwear of choice used by such non-professionals is the widely available sports shoe or "trainer".

As a result, it is not uncommon for much bruising to occur on the underside of the foot used to engage the bar 2 of the implement 10 by such non-professional users of these implements 10.

The manufacturers of such ground penetrating implements have recognised this problem and have attempted to solve it through the following methods:

1) U.K. Patent Application No. 8923737.4 employs a tapered blade wherein the cross-sectional area of the bar 2 is substantially greater than the cross-sectional area of the ground engaging bar 6. This integral construction of a "flanged" bar 2 does indeed overcome the problem of bruising and injury to the underside of the foot by a non-professional user.

2) U.K. Patent Application No. 8312968 once again employs an integral essentially flanged foot rest to substantially reduce the risk of bruising or otherwise to the foot of the user of such an implement.

3) U.S. Patent No. 5 402 853 also employs an integral foot rest for use with a weed pulling implement and achieve the same effect as the previous two U.K. patent applications.

All of these forms of foot rest do indeed alleviate the problem as outlined in this specification hereinbefore described. However, the integral construction of these "flanged" implements forces the non-professional to buy each product on an individual basis if the non-professional wants to reduce the risk of injury to his or her foot. As each implement is likely to be expensive, this is certainly a financial problem to the non-professional.

Furthermore, many non-professionals already have access to a range of existing ground penetrating implements 10 that have been "lying around" a garage or shed for a number of years that are still perfectly serviceable and that do not have "flanged" bars 2. As such, there is a tremendous reluctance to purchase the implements that are the subject of the existing patent applications hereinbefore described and, as such, the problem of foot injury still persists. As yet, there is no financially cheap solution to this foot injury problem.

It is an object of the present invention to provide a cheap alternative that solves the problems hereinbefore described and that can be readily utilised with existing ground penetrating implements that the non-professional already has in his/her possession. However, as will be apparent hereinafter, the invention may find application by all individuals involved in digging work, especially individuals using a variety of ground penetrating implements and individuals involved in prolonged and/or extensive digging work.

In its broadest aspect, the invention provides an attachment for a foot-driven, ground penetrating implement (such as a spade), comprising a pad for engagement by the foot and means for mounting said pad to the ground penetrating portion of the implement or to the adjacent region of the implement shaft, whereby in use to spread the force applied to the ground penetrating portion over an increased area of the sole of the user's foot.

Preferably, the means enabling the attachment to be readily demountable comprises a channel on the underside of the foot pad which is so proportioned as to embrace the edge region of the blade, and one or more screws penetrating the or each of the channel walls to bear against the blade face and trap the blade edge region of that face within the channel.

More preferably still, the channel is no more than three quarters the length of the pad.

Preferably, the channel as specified in the previous paragraph is substantially centrally located on the underside of the foot pad, along die longitudinal axis thereof.

Preferably, the channel as specified in the previous two paragraphs is substantially straight.

Optionally, for every two screws penetrating a selected one of the channel walls, there is another screw penetrating the other channel wall.

The said (or) other screw may be positioned between, preferably approximately .__

-5- midway between, the said two screws.

Preferably, the foot pad is faced on its foot-engaging surface with resilient material.

Preferably, the padded portion of the foot pad is located within a recess of the top surface of the pad in its normal attitude of operation.

Preferably, the padded region of the foot pad is ribbed or treaded.

The invention also includes within its scope an attachment substantially as herein described with reference to and as illustrated in any appropriate selection or combination of Figures 2 to 5 of the accompanying drawings.

The invention also includes within its scope the combination of an attachment according to any of the preceding statements and an implement adapted to carry it.

In the accompanying drawings :-

Figure 1 illustrates the essential features of a typical ground penetrating implement, in this particular example a spade;

Figure 2 illustrates side, underside and end views of one particular embodiment of the invention;

Figure 3 illustrates side, underside and end views of another embodiment of this particular invention;

Figure 4 illustrates a spade incorporating one of the preferred embodiments of the present invention;

Figure 5 illustrates a spade incorporating another preferred embodiment of the present invention;

Figure 6 illustrates side, underside and end views of another embodiment of the present invention;

Figure 7 illustrates two end view portions of separate embodiments of the attachment that show different types of resilient materials incorporated into the top surface of the attachment pad in its normal attitude of operation; and

Figure 8 illustrates a perspective view of yet a further alternative embodiment of the present invention that incorporates an integral ribbed non-resilient top surface for the attachment pad.

Throughout this section of the specification, the use of the word "integral" is intended to cover not only something which is formed from the outset as one single-entity component, but also anything which, whilst being assembled from a plurality of initially disparately-produced integers, ends up as one overall and normally non-dismantlable structure.

Figure 2 illustrates one embodiment of the present invention and illustrates an attachment for a foot-driven ground penetrating implement such as a spade and is generally referenced 11. The attachment 11 includes a foot-engaging pad 16, which in use projects from the blade region 1 or the blade-adjacent shaft region (or neck) 3 of the implement to engage the sole of the implement-user's foot in a way which spreads the otherwise excessively localised force imposed on the sole by the blade edge or bar 2 as the foot drives the blade 1 into the ground. Integral with the underside of the foot-engaging pad 16, is a channel 15 formed from a sheet of material pressed into a "C" shape and rivetted onto the pad 16.

In this particular embodiment, the channel 15 is formed from the protruding surfaces 8 of the "C" as illustrated in Figure 2. The channel 15 is substantially centrally located on the underside of the pad 16 and is substantially continuous throughout its length except for a plurality of threaded apertures 9 so designed as to accept screws 7. The length of the channel 15 which in this embodiment is substantially straight, extends three quarters of the way down the length of the underside of the foot-engaging pad 16.

The channel 15 embraces the bar 2 in use and is secured to the blade 1 via the screws 7. As the neck 3 of the shaft 4 of the implement 10 is typically of greater cross-sectional area than the rest of the shaft 4, the attachment 11 is so fitted to the bar 2 that the portion of the foot engaging pad 11 that extends beyond the limit of the channel 15 is that part of the attachment 11 which abuts the neck 3 of the implement 10 when in use. ' As can be seen, the attachment 11 is readily demountable and can be fitted to most forms of ground penetrating implements of the type generally referenced in this specification.

In this particular embodiment, the threaded apertures 9 are to be found on both walls of the channel forming portions 8 and, as such, the screws 7 can penetrate each respective wall of the channel 15. Furthermore, as specifically indicated in Figure 2, for every two screws 7 penetrating a selected one of the channel walls 8, there is another screw 7 penetrating the other channel wall 8. In addition, the said or other screw 7 is positioned between, preferably approximately midway between, the other two screws 7.

The width of the channel 15 in this particular embodiment is sufficiently wide enough to accommodate any curvature in the blade 1. Figure 3 illustrates an alternative embodiment of the present invention and illustrates an attachment generally referenced 12 which once again comprises a foot-engaging pad 16 with a substantially parallel sided straight continuous channel 15 cut into walls 8 of the foot pad 16 providing a channel of integrally formed construction. The channel 15, as can be seen in Figure 3, is centrally located along die underside of the foot pad 16 and, once again, the channel 15 runs along substantially three quarters of the length of the foot pad. That portion of the foot pad 16 Λat extends beyond the channel 15 is recessed 17 to receive a portion of a clamping member 13 known commercially as a jubilee clip. A portion of the inner wall of the jubilee clip when in use is in contiguous relationship with the exterior wall of the curved surface 14, that exterior wall forming one wall of the recess 17.

The interior wall of the curved surface 14 and substantially the remainder of the interior wall of the jubilee clip when in use fit around the neck 3 of the implement 10, the channel 15 embracing the bar 2 of the implement 10 at the same time. The jubilee clip is tightened forming a further embodiment of an attachment which spreads the otherwise excessively localised force imposed on the sole by the bar 2 that forms part of the blade 1 of the implement 10. This particular embodiment of the present invention is illustrated in its in use position more clearly in Figure 5.

Of course the embodiments just described have been described by way of example only and a number of modifications can be made without departing from the scope of the invention. For instance, the foot pad 16 could incorporate a layer of resilient material 20 on the top or sole-engaging surface of the attachment in its in use position. For example, Figure 6 illustrates an alternative embodiment generally referenced 18 that incorporates such a layer 20 on the top surface of the attachment pad in its normal attitude of operation. In this particular embodiment, the resilient layer 20 seats or is otherwise located within a recessed 98/0

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21 top region of the foot pad 16 in such a manner that each surface of the recess 21 is in contiguous relationship with some aspect of the resilient layer 20. The purpose of the recess 21 is to prevent lateral or other movement of the resilient layer 20 when the attachment 18 is in use, i.e. when those forces that would be exerted on the padded layer 20 by a user's shoe are urged onto it. In this particular embodiment, the layer 20 is treaded or ribbed to aid the "grip" of the wearer's shoe onto the attachment. In alternative embodiments not illustrated, not every surface of the layer 20 need necessarily be in contiguous relationship with each surface of the recess 21.

In the embodiment illustrated in Figure 6, it will also be noted that the channel 15 of the attachment pad 18 is not centrally located along the longitudinal axis of the attachment 18. In fact one of the protruding surfaces 8 that make up the channel 15 in this particular embodiment forms the leading edge of the attachment 18. This type of attachment when fitted to a spade or fork in the correct manner enables substantially "vertical" penetration of the ground penetrating implement followed by a rotary levered movement to remove the "sod" or other material with minimal interference or contact of the attachment 18 on the ground, as the ground penetrating implement is used in its rotary/levering action to remove the "sod" or other material. Furthermore, in this particular embodiment, the opposite protruding surface 8 that does not form part of the leading edge of the attachment 18 is further strengthened by a thickened region 19 that runs the entire length of the protruding surface 8. For the avoidance of doubt, the term "length" when describing the preferred embodiments of this specification refers to that axis which is the longitudinal axis of the channel 15. The screws 7 in this particular embodiment will accept so-called .Allen keys. The underside surface 31 of the resilient layer 20 in its normal attitude of operation is provided with a detachable sheet to reveal a "gummed" or otherwise "sticky" underside surface 31 to enable the resilient layer 20 to be adhered to the recessed region 21 of the attachment 18. In alternative embodiments not illustrated, this resilient layer 20 could be attached by other means known to the sleilled addressee of this specification.

In an alternative embodiment not illustrated, the walls 8 of the second embodiment of this invention as illustrated in Figure 3 could be apertured in a similar manner to the first embodiment illustrated in Figure 2 to receive screws to aid the securing of the second embodiment of this invention to the blade 1.

In yet a further alternative embodiment not illustrated, the channel 15 could be tapered either along its length (or along its height; in other words, the thinnest portion of the taper is along the underside of the foot-engaging pad 16 where the channel 15 meets the pad 16). These particular configurations could aid embodiments that are merely "friction-fit" systems. In other alternative embodiments, the channel 15 could be curved (and/or tapered in the manner described above) to aid embracement of the pad 16 to the digging implement 10.

Figure 8 illustrates a further alternative embodiment of the present invention and it will be immediately apparent that in this particular embodiment the whole attachment generally referenced 32 can be cast as a single integral unit to be supplied wiui screws 7. The treaded or ribbed top surface 29 of the attachment 32 is, by definition, integral with the attachment 32, the treaded region 29 and the attachment 32 together forming a single-entity component from the outset. The treaded region 29 is not made of resilient material. The reinforcing member 30 in this particular embodiment is curved as opposed to straight edged as illustrated in Figure 6 and the exterior face 28 of one of the protruding surfaces 8 is devoid of apertures adapted to receive screws 7. Therefore in this particular embodiment the screws 7 only run along the length of the opposite exterior face of the protruding surface 8 of the attachment 32.

In alternative embodiments not illustrated, the location of the apertures 9 adapted to receive screws 7 need not necessarily be in linear alignment along the or each length of the protrusions 8. There may be advantages in offsetting these apertures in a generally non-linear arrangement, for example the middle aperture 9 could be raised or lowered along the height of the attachment. Likewise, either of the end apertures could also be raised or lowered such that the "three in a line" arrangement of apertures could be "two in a line" with an offset or, alternatively, three completely offset. Furthermore, in each of the relevant respective embodiments illustrated, not only are the apertures 9 arranged in a linear fashion, each of the apertures are equidistant from each other. In alternative embodiments not illustrated, at least two apertures need not necessarily be equidistant from each other. In addition, currently, each respective aperture 9 located along the length of one of the protruded surfaces 8 is in parallel alignment (with respect to the general plane of the top surface of the attachment in its normal attitude of operation) with the apertures 9 located on the opposite protruded surface 8 of the attachment. In other embodiments this need not necessarily be so.

Turning now to Figure 7, this illustrates two embodiments of part of the attachment generally referenced 24 seen from the end. In these two embodiments, there is shown a padded region 25 formed from resiliently flexible material located within a recessed top region of the foot pad and these embodiments will now be described in further detail.

In the upper embodiment illustrated in Figure 7, the walls of the recessed surface 26 are straight and angled away from the vertical. The resilient layer 25 need not necessarily be adhered to the attachment 24 as a result of this angled recess. It could simply be a "friction-fit" type arrangement. The resilient layer 25 in this particular embodiment is not treaded or ribbed; however it does protrude beyond the top surface of the attachment 24. It will be seen from the top embodiment of Figure 7, that the face 35 of the recessed surface 26 is curved and the complementary face of the resilient layer 25 is also so sized and shaped as to lie in contiguous relationship with the surface 35 when in use. It will also be apparent that the sloping edges of the recessed surface 26 are straight along their entire length.

In the lower embodiment of Figure 7, the resilient layer 25 is treaded and does not protrude beyond the top surface of the attachment 24. Furthermore, the surface 36 of the recessed surface 27 is substantially straight whilst the angled surfaces of the recessed surface 27 are curved along their entire length.

In yet further embodiments not illustrated, the attachment pad itself could be made of a sufficiently resilient but relatively rigid material, for example a plastics material, the sides 8 of the channel 15 gripping the bar 2 and blade 1 when the attachment is in use simply as a result of the resilient nature and design.

Preferred materials for the manufacture of the attachment are metals, plastics, metal alloys or any appropriate selection or combination of the above. Preferably, the metal used is aluminium, from which the attachment pad is formed by extrusion. Examples of plastics materials are polyurethanes, polythenes or polypropylenes suistably adapted for the purpose and such methods are known to relevant skilled addressees of this specification and the skilled person in this particular instance will be a polymer chemist.

Claims

•13-Claijns

1. An attachment for a foot-driven, ground penetrating implement (such as a spade), comprising a pad for engagment by the foot and means for mounting said pad to the ground penetrating portion of the implement or to the adjacent region of the implement shaft, whereby in use to spread the force applied to the ground penetrating portion over an increased area of the sole of the user's foot.

2. .An attachment according to claim 1, wherein the foot pad and the mounting means are integrally formed.

3. An attachment according to claim 2, wherein the foot pad has an underside walled channel for engagement over the top edge of the ground penetrating portion of die implement.

4. An attachment according to claim 3, in which the walls of the channel are penetrated by tightenable screws to enable the attachment to be fixed to the top region of the ground penetrating portion.

5. An attachment according to any of claims 1 to 4, made of extruded aluminium.

6. An attachment according to any of claims 1 to 5, in which the mounting means includes a clip for gripping the shaft of the implement adjacent the blade.

7. An attachment according to any of claims 1 to 6, in which the foot pad is faced on top with a resilient layer.

8. An attachment according to claim 4 or any claim appendant thereto, wherein the channel has sufficient width to accommodate curvature of the top of the ground penetrating portion.

9. .An attachment according to claim 1, in which the foot pad has a ribbed or treaded surface for engagment by the user's foot.

10. An attachment according to any of claims 1 to 9, in combination with a foot- driven ground penetrating implement to which the attachment is releasably mountable.