SOIL COVERING AND PLANTING APPARATUS

Abstract

A soil bed covering and planting apparatus is adapted to be carried along the length of a soil bed by a conveyer vehicle and includes a cover material reel configured to retain and supply a sheet of cover material, and a compaction roller configured to feed cover material over a soil bed and to press the cover material onto the soil bed. Two spike hammers are positioned adjacent to and at opposite sides of the compaction roller, each being configured to drive at least one spike through the cover material into the soil bed. An actuation structure is associated with each spike hammer and urges the spike hammer against a spike. A piercing assembly forms a series of holes in the sheet of cover material and engages with a drive structure that reciprocates the piercing assembly to drive one end of the piercing assembly through the sheet of cover material.

Claims

1. A soil bed covering and planting apparatus adapted to be carried along the length of a soil bed by a conveyer vehicle, the apparatus including: a cover material reel configured to retain and supply a sheet of cover material, a compaction roller configured to feed cover material supplied by the cover material reel over a soil bed and being configured to press the cover material on to the soil bed, two spike hammers positioned adjacent to and at opposite sides of the compaction roller, each being configured to drive at least one spike through the cover material and into the soil bed to secure the cover material to the soil bed, an actuation structure associated with each spike hammer configured to urge the spike hammer against a spike, and a piercing assembly arranged to form a series of holes in the sheet of cover material, the piercing assembly being engaged with a drive structure which is configured to reciprocate the piercing assembly to drive one end of the piercing assembly through the sheet of cover material.

2. A soil bed covering and planting apparatus as claimed in claim 1 wherein the piercing assembly defines a hollow bore configured to receive at least one plant to be planted in the soil bed, the piercing assembly also defining an entry port through which a plant can be introduced to the hollow bore.

3. A soil bed covering and planting apparatus as claimed in claim 2 wherein the end of the piercing assembly driven through the cover material defines a pair of jaws movable between an open configuration and a closed configuration, wherein in the closed configuration the jaws define a piercing blade and in the open configuration the jaws define a delivery port which allows a plant located in the hollow bore to exit the bore and be delivered to the soil bed through a hole formed in the cover material by the piercing assembly.

4. A soil bed covering and planting apparatus as claimed in claim 3 wherein the drive structure moves the piercing assembly so that one end of the assembly is driven through the sheet of cover material to form a planting hole in the underlying soil bed with action of gravity and/or the impact of the lower end of the piercing assembly with the cover material and soil bed causing a plant introduced into the hollow bore to move down the bore.

5. A soil bed covering and planting apparatus as claimed in claim 1 wherein the drive structure is associated with a trigger mechanism which includes a magnetic sensor and a ground following wheel incorporating a number of magnets mounted on a side of the wheel, the magnets being positioned to rotate past a magnetic sensor.

6. A soil bed covering and planting apparatus as claimed in claim 1 wherein the drive structure configured to reciprocate the piercing assembly includes at least one pneumatic ram.

7. A soil bed covering and planting apparatus as claimed in claim 1 which includes a support frame and the piercing assembly is engaged with the support frame through a lateral adjustment mechanism.

8. A soil bed covering and planting apparatus as claimed in claim 1 which includes a support frame and the piercing assembly engaged with the support frame through a height adjustment mechanism.

9. A soil bed covering and planting apparatus as claimed in claim 1 which includes a support frame and the piercing assembly engaged with the support frame using a resilient tilt mounting.

10. A soil bed covering and planting apparatus as claimed in claim 1 wherein the actuation structure associated with a spike hammer includes a pneumatic ram assembly.

11. A soil bed covering and planting apparatus as claimed in claim 1 wherein the actuation structure associated with a spike hammer includes a trigger mechanism which incorporates a ground travelling wheel rotated by the progress of the conveyor vehicle.

12. A soil bed covering and planting apparatus as claimed in claim 1 wherein the compaction roller defines a ground contact profile which is complementary to the profile of the soil bed to be prepared

13. A soil bed covering and planting apparatus as claimed in claim 12 wherein the compaction roller has a cylindrical form with a tapered central waist which complements the shape of a ridged soil bed.

14. A soil bed covering and planting apparatus as claimed in claim 1 which includes a ridging structure configured to form a raised ridge of soil as the conveyor vehicle moves along the length of a soil bed.

15. A soil bed covering and planting apparatus as claimed in claim 14 wherein the ridging structure incorporates at least two substantially vertically orientated soil collection blades which are angled towards an open apex region.

16. A soil bed covering and planting apparatus as claimed in claim 1 which includes an irrigation conduit reel configured to retain and supply a length of irrigation conduit over the soil bed and under the cover material.

17. A soil bed covering and planting apparatus as claimed in claim 16 wherein the irrigation conduit is fed out on top of the soil bed offset from the centre of the width of the sheet of cover material.

18. A soil bed covering and planting apparatus as claimed in claim 1 which includes an air pump and at least one pneumatic accumulator tank.

19. A soil bed covering and planting apparatus as claimed in claim 18 which includes a plurality of pneumatic accumulator tanks.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Additional and further aspects of the present invention will be apparent to the reader from the following description of embodiments, given in by way of example only, with reference to the accompanying drawings in which:

[0057] FIG. 1 shows a side view of a soil bed preparation apparatus as provided in accordance with one embodiment of the invention, and

[0058] FIG. 2 shows a detailed view of the ridging structure integrated in the apparatus of FIG. 1,

[0059] FIGS. 3a, 3b, 3c, 3d and 3e show a number of perspective views of the cover reel, compaction roller and irrigation conduit reel provided in the apparatus shown with respect FIG. 1,

[0060] FIG. 4 shows a view of one of the two spike hammers integrated into the apparatus of FIG. 1,

[0061] FIG. 5 shows components of the trigger mechanism which operates one of the spike hammers integrated provided the apparatus of FIG. 1,

[0062] FIG. 6 shows a view of the piercing assembly provided in the apparatus of FIG. 1,

[0063] FIGS. 7a, 7b and 7c show the range of motion and configuration of the piercing assembly of FIG. 6 during various stages of operation,

[0064] FIGS. 8a, 8b and 8c show the motion of the side mounted pneumatic rams and lever arms of FIG. 6 as the jaws moved from their closed to open positions,

[0065] FIG. 9 shows components of the trigger mechanism which triggers the actions of the piercing assembly shown with respect to FIGS. 7b and 7c,

[0066] FIG. 10 shows a side schematic view of a soil planting and covering apparatus provided in accordance with an alternative embodiment to that shown with respect to FIGS. 1 to 9,

[0067] FIG. 11 shows an end view of the piercing assembly illustrated with respect to FIG. 10,

[0068] FIG. 12 shows a side view of the piercing assembly illustrated with respect to FIGS. 10 and 11,

[0069] FIG. 13 shows perspective and side views of the drive structure which moves the piercing assembly illustrated with respect to FIGS. 11 and 12,

[0070] FIGS. 14a through 14g illustrate the sequence of operational of movements performed by the piercing assembly of FIGS. 11-13 relative to the rotation of a ground following wheel trigger mechanism,

[0071] FIGS. 15a, 15b and 15c show front, side and top views of one of the spike hammers shown with respect to FIG. 10,

[0072] FIG. 16 shows components of a spike magazine drive system incorporated into the spike hammer shown with respect to FIGS. 15a-15c,

[0073] FIG. 17 show an exploded schematic view of parts of the spike hammer illustrated in FIGS. 15a-c, and

[0074] FIGS. 18a through 18e illustrate the sequence of operational movements performed by the spike hammer of FIGS. 15 through 17 relative to the rotation of a ground following wheel trigger mechanism.

[0075] Further aspects of the invention will become apparent from the following description of the invention which is given by way of example only of particular embodiments.

BEST MODES FOR CARRYING OUT THE INVENTION

[0076] FIG. 1 shows a side view of a soil covering and planting apparatus 1 as provided in accordance with a preferred embodiment of the invention.

[0077] In the embodiment shown the invention defines a main support frame 2 used to locate a ridging structure 3, irrigation conduit reel 4, cover material reel 5, a pair of spike hammers 6 and compaction roller 7, piercing assembly 8 and pneumatic accumulator tank 9. These components are mounted on the support frame 2 which is lifted and moved along the length of a soil bed by a conveyer vehicle tractor 10. The tractor is also used to lift and support an air pump 11 which supplies compressed air to the accumulator tank 9.

[0078] In the embodiment shown the apparatus 1 is configured to move along a flat area of soil. As it moves over the soil bed it forms a raised ridge through the action of the ridging structure, applies a length of irrigation conduit supplied by the irrigation conduit reel, and then covers the raised ridged bed with a sheet of weed deterrent cover material supplied by the cover material reel and pressed and pinned into place by the spike hammers and compaction roller. The piercing assembly mounted to the rear of the support frame then operates to cut a series of holes in the cover material at the top of the ridged soil bed and to deposit a plant into the hole formed under each cut.

[0079] FIG. 2 shows a detailed view of the ridging structure 3 integrated in the apparatus of FIG. 1. As can be seen from FIG. 2 this structure incorporates two sets of paired angled blades 12 which project upwards from the soil towards an open apex region 13 at the rear of the structure. The front of the structure defines an open leading throat which is used to collect soil from a wide span to be mounted into the ridged soil bed.

[0080] FIGS. 3a, 3b, 3c, 3d and 3e show a number of perspective views of the cover reel 5, compaction roller 6 and irrigation conduit reel 4 provided in the apparatus shown with respect FIG. 1. In the views shown the progress of the conveying tractor is moving in the direction of left to right. This collection of components is arranged so that the irrigation conduit reel 4 firstly deploys its conduit 14 directly onto the soil bed. The cover reel 5 then supplies a loose sheet of material 15 down to the compaction roller 6 by way of a series of intermediate spreading and tensioning rollers 16, as shown in FIG. 3d. The compaction roller 6 then compresses the irrigation conduit and cover material onto the soil bed, with a following of spike hammers (not shown) being used to turn to pin the edges of the cover material in place.

[0081] FIG. 3e also shows a perspective view of the compaction roller 6, and illustrates how in this embodiment defines a ground contact profile which is complementary to the profile or shape of the soil bed to be prepared. The compaction roller has a cylindrical form with a tapered central waist which complements the shape of the ridged soil bed.

[0082] FIG. 4 shows a view of one of the two spike hammers 7 integrated into the apparatus of FIG. 1. As can be seen from FIG. 5 an array of staple shaped spikes 17 are arranged on a track leading to the spike hammer 7. An operator urges the staples 17 towards and underneath the spike hammer as it is reciprocated up and down by a pneumatic ram based actuation system 18.

[0083] FIG. 5 shows components of the trigger mechanism which operates one of the spike hammers 7 integrated provided the apparatus of FIG. 1.

[0084] Preferably each actuation structure 18 engaged with a spike hammer includes a trigger mechanism 19 which controls the placement distance between spikes used to secure one edge of the cover material to the soil bed. These trigger mechanisms can be used to trigger the application of a driving force by the actuation structure to a spike hammer at particular times or when the conveyor vehicle has traveled a certain distance.

[0085] In this embodiment the trigger mechanism 19 incorporates a ground travelling wheel 20 which is rotated by the progress of the tractor. This ground travelling wheel rotates a gear 21 connected via a drive chain 22 through to a cam mechanism (not shown) which repetitively trips a trigger switch (not shown) operating the associated spike hammer. The delay time between hammer triggersand hence the distance between adjacent pins or staplescan be adjusted by changing the size of the gear mounted to the ground travelling wheel.

[0086] FIG. 6 shows a view of the piercing assembly provided in the apparatus of FIG. 1. FIGS. 7a, 7b and 7c show the range of motion and configuration of the piercing assembly integrated into the apparatus of FIG. 1 during various stages of operation.

[0087] In the embodiment shown the piercing assembly incorporates an elongate shaft 23 which defines a hollow interior bore. The top of this shaft is open and defines an inlet port 24 which can receive plants into the hollow interior bore of the shaft. The opposite end of the assembly defines a pair of jaws 25, shown in a closed configuration in FIGS. 7a and 7b, and in an open configuration in FIG. 7c. As can be seen from FIGS. 7a and 7b the leading edges of these jaws are the first surfaces to contact the sheet of cover material and together define a piercing blade 26. As can be seen from FIG. 7c the same jaws placed in an open configuration define a delivery port 27 giving access to the hollow interior of the bore and allowing a plant to drop down into the soil bed exposed by the action of the piercing assembly.

[0088] FIG. 6 shows in more detail components of the piercing assembly 8 which are used to move the shaft 23 up and down and to open and close the pair of jaws 25.

[0089] The shaft is connected to the end of a hydraulic ram system 28 which operates to reciprocate the shaft up and down, piercing the cover material and positioning the delivery port 27 adjacent to the underlying soil.

[0090] A series of lever arms 29 are connected to each jaw 25 located at the lower end of the shaft. An additional side mounted pneumatic ram 30 is provided for each jaw and linked to these lever arms, with the side rams being actuated in a timed manner to synchronise with the vertical reciprocal motion applied by hydraulic ram system 28.

[0091] FIGS. 8a, 8b and 8c show the motion of the side mounted pneumatic rams and lever arms as the jaws moved from their close to open positions. As can be seen from these figures each side mounted ram can push the topmost lever arm towards the shaft to open the jaws and expose the delivery port. Motion of the side hydraulic ram in the opposite direction will act to close the jaws.

[0092] FIG. 9 shows components of the trigger mechanism 31 which triggers the actions of the piercing assembly shown with respect to FIGS. 7b and 7c. This component therefore controls the distance between each plant deposited by the piercing assembly. This trigger mechanism incorporates a ground travelling wheel 32 which is rotated by the progress of the tractor.

[0093] A series of magnets 33 are mounted on the side of the wheel 32 at the same distance from the centre of the wheel to align with a magnetic sensor 34 and associated trigger electronics. As the ground wheel rotates each of the sensors shown will move past the magnetic sensor to induce a trigger pulse in the associated electronic which is used to actuate the operation of the piercing mechanism 8.

[0094] In the embodiment shown the piercing mechanism is actuated every time a magnet passes the sensor. However the behaviour of this component can be modified in other embodiments by the addition of further magnets to the wheel and/or triggering of the piercing mechanism only after the passage of a set number of magnets has been detected.

[0095] FIG. 10 shows a side schematic view of a soil covering and planting apparatus 101 as provided in accordance with an alternative embodiment to that shown with respect to FIGS. 1 to 9

[0096] Similarly with the embodiment shown with respect to FIGS. 1 to 9 the apparatus 101 of FIG. 10 also incorporates a support frame 102 which is used to mount and support the various other components of the apparatus. A ridging structure 103 is mounted to the front or forward end of the support frame and forms the leading component of the apparatus when moved along a soil bed. This ridging structure 103 shapes a loose mound of soil which is then pressed together by a set of compaction rollers 107. The end insert view 107a shown illustrates how each compaction roller 107 defines a ground contact profile which is complimentary to the profile of the soil bed being prepared. In the embodiment shown each compaction roller has a cylindrical form with a tapered central waist which complements the shape of the ridged soil bed.

[0097] An irrigation conduit reel 104 is provided to deploy a length of irrigation conduit on to the soil bed with the assistance of a series of translation rollers 110. This conduit is sandwiched between the soil bed and a layer of weed deterrent cover material supplied by a cover material reel 105. Cover material supplied by the cover material reel 105 is pressed into the soil bed by one of the compaction rollers 107 with the irrigation conduit located underneath the cover material.

[0098] The apparatus 101 also includes a pair of spike hammers 106 with one shown by the side view provided as FIG. 10. The construction and operation of these components of the invention are shown and discussed in more detail respect to FIGS. 15 to 18.

[0099] The final component of the apparatus mounted to the support frame 102 is a piercing assembly 108. The piercing assembly 108 and spike hammers 106 are connected to and powered by a pneumatic drive system which includes a series of accumulator tanks 109. The construction and operation of the piercing assembly 108 is shown and discussed in more detail with respect to FIGS. 11 to 14.

[0100] In particular, FIG. 11 shows an end view of the piercing assembly illustrated with respect to FIG. 10, while FIG. 12 shows a side view of the same piercing assembly. When used the piercing assembly 108 is arranged to form a series of holes in the sheet of cover material. These piercing operations are completed using a drive structure 135 configured to reciprocate the piercing assembly to drive one end of the piercing assembly through the sheet of cover material.

[0101] The piercing assembly defines a hollow bore 123 configured to receive at least one plant to be planted in the soil bed. Plants are fed into this hollow bore through an entry port 124.

[0102] The end of the piercing assembly driven through the cover material defines a pair of jaws 125 which are movable between an open configuration and a closed configuration, as shown in further detail with respect to FIGS. 14a through 14g. In the closed configuration shown in FIG. 11 the jaws define a piercing blade 126 which is driven through the sheet of cover material by the drive structure to form a planting hole in the underlying soil bed.

[0103] The drive structure 135 includes a pneumatic ram 128 assembly linked to the hollow bore 123 and terminating jaws 125. This ram is used to reciprocate the hollow bore and jaws up and down as shown with respect to FIGS. 14a through 14g. The ram is used to rapidly force the bore downwards and the closed jaws through the cover material so that the action of gravity and the impact with the cover material and soil causes a plant within the hollow bore to move down the bore. The jaws are then moved into the open configuration to define a delivery port (not shown) which allows a plant located in the hollow bore to be delivered to the planting hole formed in soil bed through the hole formed in the cover material. FIG. 14e shows the formation of this delivery port 127 when the jaws are opened.

[0104] FIGS. 11 and 12 also illustrate the provision of a lateral adjustment mechanism 136 which provides an intermediary component used to engage the piercing assembly 108 with the support frame 102. In the embodiment shown the piercing assembly and its associated drive structure 135 are suspended from a threaded shaft 137 linked to an electric drive motor 138.

[0105] Forward and backwards operation of this motor rotates the driveshaft to produce a lateral translation in the suspended piercing assembly. This feature therefore allows for precise adjustment of the relative position of the piercing assembly to the left and right on the support frame to adjust for deviations in the soil bed being traversed by the apparatus.

[0106] FIG. 12 also shows the provision of a resilient tilt mounting 139 and a height adjustment mechanism 143 used as intermediary components to engage the piercing assembly 108 with the support frame 102. In the embodiment shown the resilient tilt mounting is engaged with and suspends the lateral adjustment mechanism discussed above. This component is in turn suspending by a pivot connection 140 from the height adjustment mechanism which is engaged directly with the support frame.

[0107] The height adjustment mechanism incorporates a further pneumatic ram assembly 144 which lifts or lowers the pivot connection 140 relative to the support frame. This feature therefore allows for precise adjustment of the relative height of the piercing assembly 108 on the support frame 102 to adjust for deviations in height of the soil bed being traversed by the apparatus. This feature can also be used to control the depth of the planting hole formed by the operation of the piercing assembly.

[0108] The resilient tilt mounting 139 utilises the pivot connection 140 to the height adjustment mechanism 143 in combination with spring returns 141 to minimize the length of a cut formed in the surface of the cover material as the apparatus moves forward along the length of a soil bed. A deformable braking and steading element is also provided, as implemented in this embodiment by rubber tipped stop 142.

[0109] As a piercing and planting operation is taking place the support frame is still moving forward along the length of the soil bed and will therefore drag the jaw of the hollow bore along the length of the cover material in front of where a plant has been deposited. This can inadvertently rip or cut a longer hole in the cover material than is desirable if the piercing assembly is rigidly mounted to the support frame. However the resilient tilt mounting allows the resistance experienced by the jaw as the apparatus moves forward to be translated into a backward tilting motion in the piercing assembly. Once the jaws are clear of the soil bed and cover material the return springs will draw the piercing assembly back into a substantially vertical orientation and ready for the next piercing operation. The rubber tipped stop 142 brakes the motion of the piercing assembly as it moves back to a vertical orientation, as well as steadying and damping down vibrations in the piercing assembly when used.

[0110] FIG. 13 shows additional shuttle components 130 of the drive structure 135 which are used to open and close the jaws of the piercing assembly as the pneumatic ram assembly 128 reciprocates the hollow bore. This pair of shuttle components are each formed by a guide head 145 linked by a drive shaft 146 to a pneumatic ram drive assembly 147. Each guide head is linked to one of two lever arms 129 which are linked by a sequence of pivot connections to either side of the jaws. The ram 147 associated with each shuttle assembly is operated by control signals supplied by a trigger mechanism 131, formed in this embodiment by a magnetic sensor 134 mounted on the support frame 102 adjacent to a ground following wheel 132. This wheel has a magnet 133 mounted to its side in a position where the magnet will rotate past the sensor with every revolution of the wheel.

[0111] FIGS. 14a through 14g illustrate the sequence of operational movements performed by the piercing assembly of FIGS. 11-13 under the action of the drive mechanism and relative to the rotation of this ground following wheel based trigger mechanism 131.

[0112] FIG. 14a (1) shows the initial positioning of the piercing assembly as a plant is dropped through the entry port of the hollow bore and as the trigger mechanism's wheel mounted magnet rotates into alignment with the sensor.

[0113] FIG. 14b (2) shows the plant falling through the hollow bore under the action of gravity towards the jaws. At this stage of a piercing operation the rotating magnet is aligned with the sensor and a trigger signal is sent to each of the shuttle mechanisms to pull the guide heads away from the hollow bore and to activate the pneumatic ram to drive the hollow bore downwards. The guide heads of the shuttles are engaged with shoulder regions B of the lever arms as illustrated by FIG. 13.

[0114] FIG. 14c (3) shows the pneumatic ram having driven the hollow bore and jaw downwards through a cover material to form a planting hole in the underlying soil bed. The guide heads of the shuttles are engaged with shoulder regions A of the lever arms as illustrated by FIG. 13.

[0115] FIG. 14d (4) shows the guide heads beginning to be driven inwards towards the hollow bore and acting against shoulder regions A of the lever arms.

[0116] FIG. 14e (5) shows the piercing assembly after the guide heads have moved inwards and pulled the lever arms inwards towards the hollow bore, forcing the jaws to move from their closed to open configurations. This allows the plant inside the hollow bore to drop out through the exit port defined by the open jaws through the pierced cover material and into the planting hole formed by the jaws.

[0117] FIG. 14f (6) shows the operation of the pneumatic ram to lift the hollow bore upwards while the jaws remain in the open configuration. The upper sections of the tilt arms move past the guide heads of the shuttle mechanisms As discussed with reference to FIG. 12, the resilient tilt mounting provided with the piercing assembly allows it to tilt at this stage of the piercing operation to minimise the size of the hole formed in the cover material as the jaws are drawn upwards and away from the soil bed.

[0118] FIG. 14g (7) shows a return to the starting configuration of the piercing assembly prior to the supply of a plant into the interior of the hollow bore. As can be seen from this figure the wheel mounted magnet is again about to rotate into alignment with the sensor to trigger another cycle of the piercing and planting operation completed by the apparatus.

[0119] FIGS. 15a, 15b and 15c show front, side and top views of one of the spike hammers 106 of the apparatus 101 shown with respect to FIG. 10. These figures show a number of views of one of the two spike hammers positioned on opposite sides of the support frame 102 and used to drive spikes through the cover material and into the soil bed.

[0120] The spike hammer incorporates an actuation structure, which is formed in this embodiment by a hydraulic ram 118. This ram is configured to apply a driving force to a hammer element 148 which contacts the spike 117 to be driven through a sheet of cover material. The operation of the actuation structure is controlled by the components of a trigger mechanism 119, shown in further detail with respect to FIGS. 17 and 18a through 18e.

[0121] The spike hammer also includes a spike magazine drive system 149, as shown in further detail in FIG. 16. A magazine 151 of staple based spikes 117 is provided for use with the spike hammer, with a hydraulically driven pusher head 150 being provided to urge these spikes towards the end of the magazine and towards the hammer element.

[0122] FIG. 17 show an exploded schematic view of parts of the spike hammer illustrated in FIGS. 15a-c. These figures show the location of the hammer element 148 within a guide channel 152 which positions the top of the hammer element underneath the hydraulic ram 118. The hammer element is shown in perspective view 148a and top view 148b, while the guide channel is shown in perspective view 152a, front view 152b and top view 152c. The guide channel positions the bottom end of the hammer element adjacent to the spike magazine, allowing spikes to be introduced under the hammer element for subsequent driving through the cover material. Also shown is operator pedal 153 which allows for control of the spike magazine drive system shown with respect to FIG. 16.

[0123] These figures also show the provision of elements of the spike hammer trigger mechanism 119 which includes a magnetic sensor 154 mounted to the guide adjacent to a magnet 155 mounted to the front face of the hammer element. As illustrated by FIGS. 18c, 18d and 18e, this trigger mechanism also includes a second magnetic sensor 157 mounted to the support frame adjacent to a ground following wheel 156 with a further magnet 158 mounted to the side of this wheel.

[0124] FIGS. 18a through 18e illustrate the sequence of operational movements performed by the spike hammer 106 of FIGS. 15 through 17 relative to the rotation of a ground following wheel trigger mechanism 119.

[0125] FIG. 18a shows the initial state of the spike magazine prior to the use of the apparatus. FIG. 18b shows the loading of the spike magazine to ready the apparatus for use, with a user engaging the pedal to urge the loaded spikes towards the guide and hammer element.

[0126] FIG. 18c shows the spike hammer ready for use with the ground following wheel 156 rotating the magnet 158 into proximity with the sensor 157. Magnetic sensor 154 mounted to the guide does not detect the presence of magnet 155 mounted to the hammer element, indicating that the hammer element is located in the raised position shown in FIGS. 18a-c and 18e.

[0127] FIG. 18d shows the activation of the pneumatic ram 118 by a control signal issued from the magnet sensor 157 determining the magnet 158 is rotating past it. The bottom end of the hammer element is rapidly moved into contact with the adjacent spike and drives it through a sheet of weed mat. Magnetic sensor 154 detects the presence of magnet 155 mounted near the top of the hammer element and indicates that the hammer element is in the lowered position shown with respect to FIG. 18d.

[0128] FIG. 18e shows the spike hammer being reset for another operational cycle after the magnet has rotated past the sensor. The spike has been driven into the cover material and is falling behind the apparatus as it moves forward. The spike magazine drive system urges the next adjacent spike into the guide while the hammer element is drawn upwards by the pneumatic ram, with the system arriving back at the same configuration shown with respect to FIG. 18c.

[0129] In the preceding description and the following claims the word comprise or equivalent variations thereof is used in an inclusive sense to specify the presence of the stated feature or features. This term does not preclude the presence or addition of further features in various embodiments.

[0130] It is to be understood that the present invention is not limited to the embodiments described herein and further and additional embodiments within the spirit and scope of the invention will be apparent to the skilled reader from the examples illustrated with reference to the drawings. In particular, the invention may reside in any combination of features described herein, or may reside in alternative embodiments or combinations of these features with known equivalents to given features. Modifications and variations of the example embodiments of the invention discussed above will be apparent to those skilled in the art and may be made without departure of the scope of the invention as defined in the appended claims.