GB2379150A

GB2379150A - Ground Work Enabling Apparatus

Info

Publication number: GB2379150A
Application number: GB0216062A
Authority: GB
Inventors: William Lyle Warke
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-07-11
Filing date: 2002-07-11
Publication date: 2003-03-05
Also published as: GB0216062D0

Abstract

An enabling apparatus having a chassis 10 driven by powered ground engaging means and a mounting mechanism for carrying a work head 12, the mechanism being capable of raising or lowering the head above or below ground level and also being capable of oscillating the head. The mounting mechanism preferably comprises two legs 18 pivotally connected to a cross member at their upper ends, their lower ends providing an anchorage 22 for the head. The legs may also be connected to a crankshaft 24a via arms 26, the crankshaft being driven to oscillate the legs and head, and also acting as a flywheel to neutralise unwanted vibrations. Preferably a selection of work heads are provided that may be used with the apparatus. One of the work heads may be a blade for turf cutting.

Description

GROUND WORK ENABLING APPARATUS This invention relates to an enabling apparatus for use in work on the ground, the apparatus having a selection of different work heads for fitting thereto to enable the performing of different tasks on or to the ground. Primarily, the apparatus is for use as a turf cutting apparatus. Turf cutting apparatus has been used by green-keepers and grounds-staff in the sports-turf sector of their industry for many years, mostly to remove old tired turf or simply to strip off and replace worn or compacted areas. Landscapers and contractors also find turf-cutting apparatus very useful for removing grass surfaces in preparation for shrub beds and pathways, etc. or to be re-laid after construction work has been carried out.

Pedestrian and tractor-mountable versions of turf-cutting apparatus are presently available. The tractor-mountable apparatus is normally used by a specialist contractor for the purpose of stripping larger areas of turf or by personnel in turf farms for harvesting. Pedestrian-operated apparatus is more suitable for the purpose identified above and obviously the more portable the apparatus is the better. A lightweight compact apparatus is therefore desirable. However, achieving this type of apparatus without sacrificing performance from lack of traction, and without sacrificing operator comfort due to increasing vibration levels, has so far proved impossible.

Heretofore, existing cutting apparatus has an oscillating work head which can be adjusted to the required depth and pulled or pushed through the turf by a groundengaging drum or wheels. The drum or wheels have ribbed or cleated rubber treads or, in some cases, metal mesh attached to afford better traction by gripping the ground.

These measures have all been used because pedestrian operated apparatus struggle

to gain enough traction to propel the work head through the ground, especially in hard or compacted soil conditions. Several traction and vibration problems will apply in performing other work tasks using the selection of work heads.

An object of the present invention is to provide a lightweight compact enabling apparatus designed to obviate or mitigate the fore-mentioned traction and vibration problems and to increase the range of tasks the apparatus can perform.

Accordingly, the present invention is an enabling apparatus having a chassis carried by power-driven, ground-engaging means and a mounting mechanism for carrying a work head, the mounting mechanism being capable of articulation in a substantially vertical direction to raise or lower the work head above or below ground level and having means to oscillate the work head.

Preferably, the mounting mechanism comprises two transversely spaced legs united at their upper ends to a cross-member through pivot arrangements and their bottom ends each providing an anchorage for a respective limb of the work head. Both legs are also beneficially connected together by the oscillation means in the form of a crankshaft arrangement coupled by arms to the legs between their ends, the crankshaft being driven to impart the oscillation to the legs and work head. The crankshaft is beneficially designed to act as a flywheel to counter-balance and neutralise vibrations caused by the oscillating movements through the crankshaft having an increased diametered section between its arms, the section being provided with a row of shallow holes aligned with eccentric journals on the crankshaft- Preferably also, a selection of work heads are provided to be used, one at a time, with the apparatus. Desirably, one work head is a cutter blade for turf cutting, the blade being U-shaped with its web substantially the width of the chassis, and in the direction of travel, having a spine of greater thickness trailing the leading cutting edge.

Preferably also, the spine is hollow and its upper front face, in the direction of travel, has an increasing slope.

Alternatively, the spine is of invented channel shape.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which :- Fig. 1 is a diagrammatic cross-sectional view of a work head in the form of a cutter blade to be attached to an enabling apparatus, the cutter blade being shown in an in-use position cutting turf from the ground; Figs 2A and 2B are respectively a side cross-sectional view and an end view in the direction of arrow'A'of the enabling apparatus to which a cutter blade is fitted, part of a casing chassis being cut away for clarity ; Fig. 2C is a side cross-sectional view of the apparatus in a tilted position; Figs 3A, 3B and 3C are respectively a perspective view, a front view and a cross-sectional view on the line !) !-)) ! of Fig 3B of the cutter blade.

Fig. 4 is a side cross-sectional view of an enabling apparatus similar to Fig. 2A but with the cutter blade differently positioned than in Fig. 2A; Fig. 5 is a perspective view of a modified cutter blade ; Fig 6A is a perspective view of a pair of work heads to be used with an enabling apparatus, and Figs 7 B, C, D and E are perspective views of other single work heads; Fig. 7 is a perspective view of part of the mounting mechanism and crankshaft arrangement having a horizontal rack of four work heads of the type shown in Fig. 7A; Fig. 8 is a perspective view of a horizontal rack of work heads comprising a series of equi-spaced coulter blades for fitment to an enabling apparatus;

Fig. 9 is a perspective view of a vertical rack of two cutter blades for use in digging a trench; Fig. 10 is a diagrammatic cross-sectional view of the vertical rack of two cutter blades as shown in Fig. 10 shown in an in-use position cutting the trench from the ground; Fig. 11A is a perspective view of a surface work head in the form of a roller fitted to the mounting mechanism, and Figs 12B, 12C and 12D are perspective views of three other surface work heads; and Figs. 12 and 12A are respectively a diagrammatic cross-sectional view of a work head similar to that shown in Fig. 7A and to its passage through the ground and a cross-sectional view of the cutter.

Referring to the drawings, an enabling apparatus has a chassis 10 carried by power-driven, ground-engaging means and a mounting mechanism for carrying a work head shown as a cutter blade 12. The mounting mechanism is capable of articulation in a substantially vertical direction to raise or lower the blade 12 above or below ground level. Means are provided to oscillate the blade 12. The blade 12 is U-shaped with its web 12A substantially the width of the chassis 10, and in the direction of travel, has a stiffening spine 14 of greater thickness than the blade 12 trailing the leading cutting edge of the blade 12.

The cutter blades 12 have sides 12A which act as knives to slice the turf 8 to width. In the interests of leaving a clean edge on the cut turf, the sides 12B have a forward cutting edge angled forward relative to the turf surface to effect a slicing action rather than a torn ragged edge.

The spine 14 is hollow and its upper front face, in the direction of travel has an increasing slope.

The mounting mechanism comprises two transversely spaced legs 18 united at their upper ends to a hollow cross-member 20 through pivot arrangements and their bottom ends each providing an anchorage 22 for a respective limb 12B of the blade 12.

Both legs 18 are also connected together by the oscillation means in the form of a crankshaft arrangement 24 coupled by connecting rods 26 to the legs 18 at a pivot point 19 between the upper and bottom ends. The crankshaft arrangement 24 is driven to impart oscillation to the legs 18 and blade 12. The crankshaft arrangement 24, comprises a crankshaft 24A with an increased diametered section 28 centred between its connecting rods 26. The connecting rods 26 each have a large and a small end.

The small ends are connected to the legs 18 and the large ends contain bearings which run on eccentric journals 32 on the crankshaft 24A. The crankshaft 24A is supported at both ends by main bearings 30 which anchor the crankshaft 24A to the chassis 10. The crankshaft 24A is designed to act as a flywheel to counter-balance and neutralise vibrations generated by initial energy created by the oscillating movements of the legs 18 and connecting rods 26, and the section 28 of increased diameter is provided with a row of four shallow holes 34 aligned with the eccentric journals 32 on the crankshaft 24A. This makes the crankshaft 24A out-of-balance in a direction opposite to the throw of the crankshaft 24A thereby neutralising the vibrations. The mounting mechanism is differently positioned in Figs. 2A and 2B so as to make it easier for the operator to raise the work head clear of the ground such as by tilting it forward as shown in Fig. 2C without need to undo the depth setting mechanism. The balance around the centred (front) wheel axle makes it easy for the operator to tilt the apparatus forward to raise the implement clear of the ground by virtue of the placement of the

implement to the extreme rear of the apparatus a sufficient distance from the said centre wheel axle. The grip roller is located directly in front of the implement and makes a significant contribution to traction by virtue of the downward force implied by the implement in the ground and which can be applied also by the operator. Further the said layout of the apparatus ensures that no wheels or roller disturb the cut or treated turf.

Towards the bottom end of the legs 18, two apertures and a lower radius recess 36 at the bottom end are provided in vertical alignment. Two nut and bolt arrangements 38 are engaged through the apertures and carry on one side of the legs 18 a clamp-plate 40. The top of the limb 12B of each blade 12 has a downward openended slot 42 with a stub pin 44 provided below the slot 42 and extending inwardly and the cutter blade 12 is attached to the lower end of the respective leg 18 by sliding the slotted side 12B under the clamp-plate 40 until the pin 44 is located in the radius recess 36 at the bottom side of said leg 18. The blade 12 is secured by tightening the clampplate 40 through the nut and bolt arrangements 38. The upper ends of the legs 18 are pivotally attached to a respective depth-set arm 46 at pivot point 48. The depth-set arms 46 are angularly disposed to each other and fixedly attached to the tubular cross member 20 which spans between side panel upright sections 50 on both sides of a casing which forms the chassis 10 of the apparatus. A clamp rod 52 extends through the hollow centre of cross member 20 threaded at one end 52A to facilitate a clamp handle 54. A further handle 56 is fixedly attached to a depth set arm 46 on the cross member 20 to rotate the cross member 20 about the clamp rod 52 to raise and lower the blade 12 via arms 46 and legs 18. The handle is differently located in Fig. 2A. The cross member 20 is clamped between the said side panel upright sections 50 by

tightening clamp handle 54 on clamp rod 52 thereby locking and maintaining the blade 12 at the desired set depth of cut.

The cutter blades 12 are driven in oscillations forwards and backwards via the crankshaft 24A. Resistance is encountered on the forward (cutting) stroke with relatively no resistance in the backward stroke. For this reason high traction or forward propulsion in the apparatus is vital. The cutter blade 12 utilises the backward stroke of the blade to help propel the apparatus forward.

An advantage of the cutter blade 12 is that due to the stiffening spine 14, the cutting area or knife section of the blade 12 can be much thinner than heretofore and therefore more efficient at cutting or slicing through the soil (Fig. 1). This efficiency lasts throughout the life of the blade 12 indicated by the shaded area Fig. 1, i. e. until the cutting area 12A is worn back to the stiffening spine 14. The stiffening spine 14 of the blade 12 is deeper in profile than the traditional solid blade. Cutting efficiency is nonetheless gained because the turf 8 at this point has already been cut and is free to rise over this spinal part thereby reducing the traction required to propel it through the soil.

A prime mover in the form of a petrol engine 60 is provided on the chassis casing 10 to the front of the apparatus with the crankshaft arrangement 24 and blade 12 to the rear as shown in Fig. 4. From a power take off shaft 62 to which a sprocket wheel 64 is fast, the drive is through a chain belt 66 to a sprocket wheel 68 at one end of the crankshaft 24A. From the crankshaft 24A, a second chain belt 70 transfers power to a third sprocket wheel 72 on a shaft 71 carrying three ground engaging wheels (as shown in Fig 2B). The wheels 74 have cleated surfaces. Power is further transferred from the wheels 74 to a rear roller 76 by a third chain belt 78. A clutch mechanism is incorporated to disconnect the wheels and roller from the drive to enable

them to free wheel and for transport purposes. Operators handle 80 is provided as shown in FIG 2A with rubber vibration adsorbing mountings 82. A clampable pivot point 84 is provided to allow the handle 80 to be folded over the chassis casing 10 within the confines of the apparatus.

Turf cutter blades 12 oscillate at up to one thousand times per minute thereby generating vibrations which inevitably reach the operator's handles 80. The lightweight blade design has a further advantage over the exiting heavier solid type blade in that its light weight reduces the inertial energy generated by the oscillations creating less vibrations and improving operator comfort.

The spine 14'may alternatively be of inverted channel shape as shown in FIG.

6.

The forward and backward motion imparted by the apparatus is ideally suited for a range of tasks apart from removing or stripping turf 8. Specially designed work heads developed to utilise the said forward and backward motion to perform drainage sub-soil cultivation and surface treatments and are described hereinafter. The sub-soil treatment work heads as shown in Fig. 7 have been designed to perform their task at a selected depth with minimal damage or disturbance to the grass surface. This has been achieved by mounting the head on the bottom edge of a thin coulter blade 90. In one form the blade 90 to be used as a sub-soil cultivator is shown at Fig. 7A with its pair, each with a single horizontal plate extension 92 extending at right angles from the bottom of the coulter blade 90. A coulter blade 90 having a double horizontal plate extension 94 is shown at Fig 7B. To minimise the traction requirements, the extensions 94 can be extended and angled upwards at the trailing edge (as shown). The trailing edges of extensions 92,94 may be serrated (Figs 7C and E). Taking advantage of the backward stroke which arcs slightly upwards, the serrated extensions 92,94 impales

the soil and the said backward stroke loosening and cultivating it while at the same propelling the apparatus forward. A coulter blade 90 may in a further form be for drainage by creating a tunnel, the bottom of the blade 90 having a mole 96 to tunnel a drain in the sub-soil as shown in Fig. 7D. The mole may also have a hollow portion at its trailing end which could be stretched by a special tool forming a tapered end of a larger diameter of the reminder or flared in a bell shape as shown in Fig 13A in order to create a larger drain tunnel in the soil see Fig 13. This method of increasing the diameter of the mole would be more cost effective from a manufacturing point of view than a solid pin. It would also be lighter thereby keeping vibrations to a minimum. The mole may also have a serrated plate extension 98 as shown in Fig. 7E. This would perform in the same manner as described for the sub-soil cultivator, assisting the apparatus to propel the mole 96 through the ground while at the same time, cultivating the immediate soil above the drain, which could otherwise be sealed. This would increase the efficiency of the drain by encouraging moisture seepage from above. All the blades 90 could be mounted singularly on each leg 18, or rack mounted as shown in Fig 8. Rack mounted vertical-cut blades 90 without extension plates as shown in Fig 9 would be suitable for vertical cutting horizontal grasses, removing thatch and moss or adjusted deeper to scarify the soil.

A popular and effective method of draining soil is to dig a trench and fill it with free draining material. This method is labour intensive and very disruptive to any grass surface. The work head described in the following is designed to save labour, disruption and leave very little trace of work having been done. The work head is a narrower blade of the standard cutter blade 12 illustrated in Figs. 1,3 & 6. A trenchblade as shown in Fig. 10 has a narrow cut which is achieved by rack mounting the sides 12B'with two vertically-spaced blades 12'raked as shown in Fig 10 with the top

blade leading the bottom blade. This narrow blade 12'is designed to cut a deep narrow trench which, when the earth is removed, could be filled with a free draining material, such as suitably sized graded stones or pebbles. With reference to Fig. 11, a suitable thickness of turf could firstly be removed from the said drainage trench before the sub-soil is removed. The cut turf 8 could be rolled into suitable bundles for relaying.

The sub-soil could be removed in suitable sized blocks by a narrow spade. The subsoil could then be replaced with the free draining material. The cut turf 8 could then be re-laid on top of the material. This operation could be performed in either of two operations, firstly as described above or secondly using a work head with a single narrow trench blade which has an adjustable height mounting facility in which it can be set first to remove the turf then deeper to remove the sub-soil. The use of the first work head is preferred since it eliminated a second follow-up operation. Also, the total operation is carried out quicker and with consistent accuracy, eliminating errors from work head misalignment when taking the second deeper out and allowing the removed turf to fit accurately over the free draining material leaving minimum trace that the drainage work had been carried out.

Other surface treatment work heads are ideally suited for use with the enabling apparatus. These work heads are reel implements A, B, C and D which traditionally have been rolled over the ground to smooth, level or aerate the surface. The problem with this type of implement is the weight required to effectively treat the surface. These implements are shown adapted to fit on to the enabling apparatus as shown in Fig 12 and would perform their task effectively because the action of the mounting mechanism would roll them backward and forward over the surface as the apparatus moves forward. In addition to the work head coming into contact with the ground more than once forward and backward, the natural arc towards the ground on the forward stroke

imparted by the mounting mechanism would effectively help to drive these work heads into the ground. The reel work heads could be fashioned in such a manner as to be assembled in two halves. This would enable the axles to be angled right and left to apply opposing forces on each reel or roller. This would impart a sideways movement to the ground contacting work head effecting a slicing action like a harrow. The sideways action on the ground would alternate right and left with the said forward and backward stroke.

The oscillating implement principles could be applied and incorporated into larger machines including tractor mounting units, to perform ground work on large areas such as Golf Fairways, Football Pitches or Agriculture Land. Multiple legs (18) (fig. 5) would be crank driven, singularly, or in sets of two or more in a matter out of phase with each other in opposite directions, thereby keeping vibration levels to a minimum, while helping to propel the implement through or even over the ground with the minimum of traction requirements.

For turf cutting, the advantages of the apparatus are that (a) maximum traction to weight ratio has been achieved by applying drive to the central wheels and the rear roller which are designed to grip the turf thereby pushing and pulling the cutter blade 12 forward. Low friction blade 12A has been designed to reduce the traction requirements.

(b) vibration levels have been reduced by use of the lightweight cutter blade design.

Additionally, the crankshaft is designed to act as a flywheel to counter-balance the oscillating mechanism, which drives the cutter blade. Operator comfort has been enhanced by incorporating rubber mountings on the operator's handles (c) the apparatus is balanced on the said central main wheels by mounting the engine to the front and the heavy crankshaft and blade mechanism to the rear.

Pedestrian turf-cutter operators by their nature are narrow machines with a tendency to be top heavy. A low centre of gravity has been maintained by mounting heavy components such as the engine as low a possible. The low centre of gravity is balanced around the main drive wheels for maximum traction and manoeuvrability. A clutch may additionally be incorporated to disconnect the central wheels and rear roller from the drive to enable them to freewheel for transport (d) the engine and mounting mechanism layout described has the added advantage of keeping the apparatus compact and portable. In addition to a clampable pivot point which enables the operators handles to fold within the confines of the apparatus, portability has been further addressed by incorporating hinge into the depth-setting handle to enable it to fold horizontally across the top of the apparatus (e) a range of work head designs have been developed to utilise the forward and backward motion imparted by the apparatus to perform a number of turf or grass maintenance tasks. A quick change method of mounting the work heads has been developed.

The enabling apparatus can be adapted for incorporation into trailer or tractor mounting units for larger areas such as golf fairways, football pitches or agricultural land.

Variations and modifications can be made without departing from the scope of the invention described above and as claimed hereinafter.

Claims

CLAIMS 1. An enabling apparatus having a chassis carried by power-driven, groundengaging means and a mounting mechanism for carrying a work head, the mounting mechanism being capable of articulation in a substantially vertical direction to raise or lower the work head above or below ground level and having means to oscillate the work head.
2. An enabling apparatus as claimed in Claim 1, wherein a mounting mechanism comprises two transversely spaced legs united at their upper ends to a cross-member through pivot arrangements and their bottom ends each providing an anchorage for a respective limb of the work head.
3. An enabling apparatus as claimed in Claim 2, wherein both legs are also connected together by the oscillation means in the form of a crankshaft arrangement coupled by arms to the legs between their ends, the crankshaft being driven to impart the oscillation to the legs and work head.
4. An enabling apparatus as claimed in Claim 3, wherein the crankshaft is designed to act as a flywheel to counter-balance and neutralise vibrations caused by the oscillating movements through the crankshaft having a section of increased diametered between its arms, the section being provided with a row of shallow holes aligned with eccentric journals on the crankshaft.

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5. An enabling apparatus as claimed in any one of the preceding claims, wherein a selection of work heads are provided to be used, one at a time, with the apparatus.
6. An enabling apparatus as claimed in Claim 5, wherein one work head is a cutter blade for turf cutting, the blade being U-shaped with its web substantially the width of the chassis, and in the direction of travel, having a spine of greater thickness trailing the leading cutting edge.
7. An enabling apparatus as claimed in Claim 6, wherein the spine is hollow and its upper front face, in the direction of travel, has an increasing slope.
8. An enabling apparatus as claimed in Claim 6, wherein the spine is of inverted channel shape.
9. An enabling apparatus as claimed in Claim 5, wherein for each leg of each limb of a work head is provided with a downwardly open-ended slot with a stub pin provided below the slot and substantially aligned therewith.
10. An enabling apparatus substantially as hereinbefore described with reference to the accompany drawings,