Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
DEVICE FOR INSERTING SYNTHETIC FIBERS INTO THE GROUND
Document Type and Number:
WIPO Patent Application WO/2017/183977
Kind Code:
A1
Abstract:
The invention provides a device for inserting synthetic fibres into the ground, comprising a vehicle with a frame, a plurality of rotatable rolls on which synthetic fibres are wound, conveying means for conveying the fibres from the rolls to respective insertion positions above the ground, pin-shaped insertion elements arranged in at least one row above fibres at the insertion positions, and first moving means for moving the insertion elements up and down. The conveying means comprise a number of aligned side-by-side pairs of clamping elements, wherein the clamping elements are provided on connecting elements that extend along the length of the at least one row. The device further comprises cutting means for cutting the fibres at positions between two adjacent clamping elements of two adjacent, aligned pairs of clamping elements. The conveying means further comprise guide means for moving the connecting elements provided with the clamping elements in an endless path. The pin-shaped insertion elements extend within the endless path, at least in the upper position. The connecting elements are pivotally interconnected.

Inventors:
DE BRUIJN, Jeroen Jozef Maria (Taxandriaweg 15, 5142 PA WAALWIJK, 5142 PA, NL)
Application Number:
NL2017/050253
Publication Date:
October 26, 2017
Filing Date:
April 20, 2017
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
DESSO SPORTS B.V. (Taxandriaweg 15, 5142 PA WAALWIJK, 5142 PA, NL)
International Classes:
E01C13/08; D05C15/18
Domestic Patent References:
1993-04-29
Foreign References:
NL2014189A2015-08-25
NL2014189A2015-08-25
Attorney, Agent or Firm:
ALGEMEEN OCTROOI- EN MERKENBUREAU B.V. (P.O. Box 645, 5600 AP EINDHOVEN, 5600 AP, NL)
Download PDF:
Claims:
CLAIMS

1 . A device for inserting synthetic fibres (43) into the ground (13), comprising a vehicle (1) with a frame (37, 38), which can be driven in a direction of movement (59) across the ground, a plurality of rotatable rolls (14) on which synthetic fibres are wound, conveying means (21 , 23, 25, 41 , 42) for conveying the fibres relative to the frame from the rolls to respective insertion positions above the ground, wherein the fibres extend parallel to the direction of movement and to each other at the associated insertion positions, pin-shaped insertion elements (72) arranged in at least one row that extends horizontally, transversely to the direction of movement above fibres at the insertion positions, first moving means (71 ) for moving the insertion elements up and down between an upper position and a lower position relative to the frame, wherein lower ends of the insertion elements are located above the fibres at the insertion positions in the upper position and wherein the lower ends of the insertion elements are inserted into the ground in the lower position, wherein the fibres are carried along by the insertion elements and pressed into the ground during the downward movement of the insertion elements from the upper position to the lower position, the conveying means comprising a number of aligned side-by- side pairs of clamping elements (41 , 42) for the clamping of a fibre by the clamping elements of aligned pairs of clamping elements and for the clamping of side-by-side fibres by the clamping elements of side-by-side pairs of clamping elements, wherein the clamping elements are provided on connecting elements (33) that extend along the length of the at least one row, the device further comprising cutting means for cutting the fibres at positions between two adjacent clamping elements of two adjacent, aligned pairs of clamping elements, the conveying means further comprising guide means for moving the connecting elements provided with the clamping elements in an endless path relative to the frame, wherein the pin-shaped insertion elements extend within the endless path, at least in the upper position, characterised in that the connecting elements are pivotally interconnected.

2. A device according to claim 1 , characterised in that the conveying means comprise an endless conveying element (21 ) to which the connecting elements are connected, for example at an end thereof, wherein the guide means comprise a set of pulley means over which the endless conveying element is passed.

3. A device according to claim 2, characterised in that the connecting elements form an integral part of the endless conveying element.

4. A device according to claim 2 or 3, characterised in that the conveying means comprise two endless conveying elements (21 ), wherein each of the connecting elements is connected to a conveying element at one end thereof and to the other conveying element at an opposite end, wherein the guide means for each conveying element comprise a set of pulley means, over which pulley means the associated conveying element is passed.

5. A device according to claim 2, 3 or 4, characterised in that said one or are said two endless conveying elements are configured as a chain comprising pivotally interconnected links and that the pulley means are configured as sprockets that engage the chain.

6. A device according to claim 5, characterised in that each connecting element is connected to only one link of a chain.

7. A device according to any one of the preceding claims, characterised in that the clamping elements of a pair of clamping elements are provided on the same connecting element, so that the clamping elements in question are rigidly interconnected via said connecting element.

8. A device according to any one of claims 1 -6, characterised in that the clamping elements of a pair of clamping elements are provided on different connecting elements, so that the clamping elements in question are pivotally interconnected via said connecting elements.

9. A device according to any one of claims 2-8, characterised in that the clamping elements are in line with the conveying element or with the two conveying elements, seen in horizontal direction perpendicular to the conveying direction.

10. A device according to any one of claims 2-8, characterised in that the clamping elements are located on the inner side of the endless conveying element, seen in horizontal direction perpendicular to the conveying direction.

1 1 . A device according to any one of claims 2-8, characterised in that the clamping elements are located on the outer side of the endless conveying element, seen in horizontal direction perpendicular to the conveying direction.

12. A device according to any one of the preceding claims, characterised in that the endless path comprises at least one rectilinear part.

13. A device according to any one of the preceding claims, characterised in that the cutting means are provided along a rectilinear part of the endless path.

14. A device according to any one of the preceding claims, characterised in that the endless path is unround.

15. A device according to any one of the preceding claims, characterised in that the pin-shaped insertion elements are provided in at least two parallel rows.

16. A device according to claim 15, characterised in that the first moving means are configured to move the at least two rows of insertion elements up and down in an asynchronous manner.

17. A device according to claim 15 or 16, characterised in that the first moving means are configured to move the at least two rows of insertion elements up and down independently of each other.

18. A device according to any one of the preceding claims, characterised in that the cutting means comprise an elongate cutting element that can be moved back and forth between a non-operative position and an operative position by second moving means, wherein the cutting element cuts fibres being clamped by pairs of clamping elements on the outer side of one of the clamping elements of the respective pairs of clamping elements upon being moved from the non-operative position to the operative position.

19. A device according to claim 18, characterised in that the cutting element is an endless flexible cutting element that is passed over a number of pulley means, which pulley means are rotatable relative to a subframe that can be moved back and forth by the second moving means, wherein the cutting element has a first part and a second part that extend parallel to each other, spaced apart by a distance such that during movement of the cutting element from the non-operative position to the operative position the first part of the cutting element cuts fibres being clamped by pairs of clamping elements on one outer side of one of the clamping elements of the respective pairs of clamping elements and the second part of the cutting element cuts the fibres being clamped by the pairs of clamping elements on the outer side of the other of the clamping elements of the respective pairs of clamping elements.

20. A device according to any one of the preceding claims, characterised in that the first moving means are provided on the inner side of the endless path of the connecting elements.

Description:
Title: Device for inserting synthetic fibres into the ground

Description

The invention relates to a device for inserting synthetic fibres into the ground, the device comprising a vehicle with a frame, which can be driven in a direction of movement across the ground, a plurality of rotatable rolls on which synthetic fibres are wound, conveying means for conveying the fibres relative to the frame from the rolls to respective insertion positions above the ground, wherein the fibres extend parallel to the direction of movement and to each other at the associated insertion positions, pin-shaped insertion elements arranged in at least one row that extends horizontally, transversely to the direction of movement above fibres at the insertion positions, first moving means for moving the insertion elements up and down between an upper position and a lower position relative to the frame, wherein lower ends of the insertion elements are located above the fibres at the insertion positions in the upper position and wherein the lower ends of the insertion elements are inserted into the ground in the lower position, wherein the fibres are carried along by the insertion elements and pressed into the ground during the downward movement of the insertion elements from the upper position to the lower position, the conveying means comprising a number of aligned side-by-side pairs of clamping elements for the clamping of a fibre by the clamping elements of aligned pairs of clamping elements and for the clamping of side-by-side fibres by the clamping elements of side-by-side pairs of clamping elements, wherein the clamping elements are provided on connecting elements that extend along the length of the at least one row, the device further comprising cutting means for cutting the fibres at positions between two adjacent clamping elements of two adjacent, aligned pairs of clamping elements, the conveying means further comprising guide means for moving the connecting elements provided with the clamping elements in an endless path relative to the frame, wherein the pin-shaped insertion elements extend within the endless path, at least in the upper position.

Such a device is described in Dutch patent application NL 2014189

A. In the device described therein, use is made of two rotating drums. The drums are accommodated in units at the front and at the rear of a central, moving part. On the outer side of the drum, pairs of a front clamp and a rear clamp that rotate along with the drum are provided both behind one another and beside one another. The clamps of pairs of clamps arranged behind one another clamp an artificial grass strand part. After being clamped, the artificial grass strand parts are cut at positions between the successive pairs. Provided inside the drum is a row of insertion pins that can be moved up and down by means of actuators disposed outside the drum. During the downward movement, each of the insertion pins carries along an artificial grass strand part and inserts it into the ground.

The known device has several drawbacks. Performing maintenance on the insertion pins in the drum is difficult, for example, because of the limited amount of space that is available. Furthermore it is necessary to operate the device at half speed over a considerable length, viz roughly the distance between the two drums, at the end of a swath of ground into which fibres are inserted, so as to insert the fibres into the ground in a constant pattern. For a comparable reason, the device described in the aforesaid document can only be operated at half its capacity also at the beginning of a swath of ground until the moment the rear drum, too, reaches said swath.

The object of the invention is to provide a solution to or at least an improvement as regards the above problems, whether or not in possible embodiments of the invention. In order to achieve that object, the connecting elements are pivotally interconnected, whereas the above-discussed prior art device has rigid connections. The pivotal connections between the connecting elements offer much more freedom of design, so that it is for example possible to create more space for performing maintenance work within the endless path of the connecting elements.

An effective way of moving the connecting elements in the endless path can be obtained if the conveying means comprise an endless conveying element to which the connecting elements are connected at one end thereof, wherein the guide means comprise a set of pulley means over which the endless conveying element is passed, or, in particular if the conveying means comprise two endless conveying elements, wherein each of the connecting elements is connected to a conveying element at one end thereof and to the other conveying element at an opposite end, wherein the guide means for each conveying element comprise a set of pulley means, over which pulley means the associated conveying element is passed. With a view to achieving constructional simplicity it may be preferable if the connecting elements form an integral part of the endless conveying element.

It may in particular be advantageous if said one or said two endless conveying elements are configured as a chain comprising pivotally interconnected links, and if the pulley means are configured as sprockets that engage the chain. Pivoting of the connecting elements relative to each other can thus be realised via the pivotable links of the conveyor chain.

It may be advantageous in that case, for example with a view to achieving constructional simplicity, if each connecting element is connected to only one link of a chain. If two chains are used, each connecting element will be connected to one link (not more) of one chain and to one link (not more) of the other chain.

Likewise for reasons of constructional simplicity it may furthermore be preferable, whether or not in combination with the preceding possible embodiment, that the clamping elements of a pair of clamping elements are provided on different connecting elements, so that the clamping elements in question are pivotally interconnected via said connecting elements.

It may also be preferable that the clamping elements of a pair of clamping elements are provided on the same connecting element, so that the clamping elements in question are rigidly interconnected via said connecting element. The rigid interconnection between the clamping elements of a pair of clamping elements, prevents changes in the tensile stress in the fibre, at least in the part between two clamping elements, during movement in the endless path of the connecting element.

In order to prevent the tensile stress in the fibre becoming too high when turns are made, which is a potential risk in particular if the clamping elements of a pair of clamping elements are not rigidly interconnected, it may be preferable that the clamping elements are in line with the conveying element, or with the two conveying elements, seen in horizontal direction perpendicular to the conveying direction, or that the clamping elements are located on the inner side of the endless conveying element, seen in horizontal direction perpendicular to the conveying direction. It may also be preferable, however, that the clamping elements are located on the outer side of the endless conveying element, seen in horizontal direction perpendicular to the conveying direction. The fibre being clamped by the clamping elements can thus more easily be cut by the cutting means and the fibre can moreover be positioned closer to the ground in the insertion position, so that insertion of the fibre into the ground can take place in a more reliable manner.

For reasons of constructional simplicity it may furthermore be preferable if the endless path comprises at least one rectilinear part, wherein furthermore preferably the cutting means are provided along a rectilinear part of the endless path.

The greater freedom of design that the invention offers generally makes it possible to design the endless path as an unround path, for example a rectilinear or triangular path, so that more efficient use can be made of the available space.

The advantages of the invention in particular come to light if the pin- shaped insertion elements are provided in at least two parallel rows. Thus an increased capacity can be realised, also because the two parallel rows may be positioned relatively close together.

In order to reduce the mechanical load on the device according to the invention, it is as a rule advantageous if, in the case that at least two rows of pin elements are used, the first moving means are configured to move the at least two rows of insertion elements up and down in an asynchronous manner.

In use it may also be advantageous if the first moving means are configured to move the at least two rows of insertion elements up and down independently of each other, for example at the end of a swath of ground.

If the cutting means comprise an elongate cutting element that can be moved back and forth between a non-operative position and an operative position by second moving means, wherein the cutting element cuts fibres being clamped by pairs of clamping elements on the outer side of one of the clamping elements of the respective pairs of clamping elements upon being moved from the non-operative position to the operative position, said cutting of the fibres can take place very quickly.

If the cutting element is an endless flexible cutting element that is passed over a number of pulley means, which pulley means are rotatable relative to a subframe that can be moved back and forth by the second moving means, wherein the cutting element has a first part and a second part that extend parallel to each other, spaced apart by a distance such that during movement of the cutting element from the non-operative position to the operative position the first part of the cutting element cuts fibres being clamped by pairs of clamping elements on one outer side of one of the clamping elements of the respective pairs of clamping elements and the second part of the cutting element cuts the fibres being clamped by the pairs of clamping elements on the outer side of the other of the clamping elements of the respective pairs of clamping elements, the fibres can be cut simultaneously on the two opposite outer sides of adjacent pairs of clamping elements in a single stroke of the cutting element.

The above embodiments of the cutting means can also be used advantageously with insertion devices according to the prior art. The invention for that purpose provides a device for inserting synthetic fibres into the ground, the device comprising a vehicle with a frame, which can be driven in a direction of movement across the ground, a plurality of rotatable rolls on which synthetic fibres are wound, conveying means for conveying the fibres relative to the frame from the rolls to respective insertion positions above the ground, wherein the fibres extend parallel to the direction of movement and to each other at the associated insertion positions, pin-shaped insertion elements arranged in at least one row that extends horizontally, transversely to the direction of movement above fibres at the insertion positions, first moving means for moving the insertion elements up and down between an upper position and a lower position relative to the frame, wherein lower ends of the insertion elements are located above the fibres at the insertion positions in the upper position and wherein the lower ends of the insertion elements are inserted into the ground in the lower position, wherein the fibres are carried along by the insertion elements and pressed into the ground during the downward movement of the insertion elements from the upper position to the lower position, the conveying means comprising a number of aligned side-by-side pairs of clamping elements for the clamping of a fibre by the clamping elements of aligned pairs of clamping elements and for the clamping of side-by-side fibres by the clamping elements of side-by-side pairs of clamping elements, wherein the clamping elements are provided on connecting elements that extend along the length of the at least one row, the device further comprising cutting means for cutting the fibres at positions between two adjacent clamping elements of two adjacent, aligned pairs of clamping elements, the conveying means further comprising guide means for moving the connecting elements provided with the clamping elements in an endless path relative to the frame, wherein the pin-shaped insertion elements extend within the endless path, at least in the upper position, wherein the cutting means comprise an elongate cutting element that can be moved back and forth between a non-operative position and an operative position by second moving means, wherein the cutting element cuts fibres being clamped by pairs of clamping elements on the outer side of one of the clamping elements of the respective pairs of clamping elements upon being moved from the non-operative position to the operative position and wherein the cutting element may be an endless flexible cutting element that is passed over a number of pulley means, which pulley means are rotatable relative to a subframe that can be moved back and forth by the second moving means, wherein the cutting element has a first part and a second part that extend parallel to each other, spaced apart by a distance such that during movement of the cutting element from the non-operative position to the operative position the first part of the cutting element cuts fibres being clamped by pairs of clamping elements on one outer side of one of the clamping elements of the respective pairs of clamping elements and the second part of the cutting element cuts the fibres being clamped by the pairs of clamping elements on the outer side of the other of the clamping elements of the respective pairs of clamping elements.

In order to utilize the width of the device according to the invention as optimally as possible, it may be preferable that the first moving means are provided on the inner side of the endless path of the connecting elements.

The invention will now be explained in more detail by means of a description of an insertion device according to the invention, in which reference is made to the following schematic figures.

Figure 1 is a perspective view of an insertion device according to the invention;

Figure 2 is a side view of the insertion device of figure 1 ;

Figure 3 is a vertical longitudinal sectional view of the injection unit of the insertion device of figures 1 and 2; Figures 4A and 4B are perspective views of one side of the injection unit of figure 3;

Figure 5 is a side view of a part of the conveying device that forms part of the injection unit of figure 3;

Figure 6 is a sectional view along the line VI-VI in figure 5;

Figure 7 is a horizontal view transversely to the view shown in figure

6;

Figure 8 is a perspective view of the clamping system that forms part of the conveying device;

Figure 9 is a perspective view of the cutting device that forms part of the injection unit of figure 3;

Figures 10a and 10b are side views showing the cutting device of figure 9 in the non-operative position and the operative position, respectively;

Figure 1 1 shows a part of a conveying device that can form an alternative to the conveying device of figure 5;

Figure 12 is a sectional view along the line XI I-XI I in figure 9.

Figure 1 shows a device for inserting synthetic fibres into the ground. The insertion device is configured as a self-propelled vehicle 1 . The vehicle 1 comprises a drive unit 2 provided with an injection unit 3 at the front thereof, which injection unit is moved forward in the direction of movement 59 by the drive unit 2 in use.

The drive unit 2 comprises two tracks 5, which pass over sprockets 4. The sprockets 4 are mounted for rotation relative to the chassis of the drive unit 2, which chassis supports a housing 6. In the housing 6 an electric motor is provided, which drives one of the two sprockets 4 associated with a track 5. The electric motor is connected to batteries 7 provided at the rear of the housing 6. The batteries 7 also function as counterweights for the injection unit 3. The drive unit 2 is further provided with a water container 8 on top of the batteries 7, which container also functions as a counterweight when filled with water. At the rear of the tracks 5, the drive unit 2 is provided with a roller drum 9 (not shown in figure 1 ) under the batteries 7.

At the front, the injection unit 3 comprises a roller drum 10 comparable to the roller drum 9. The drive unit 2 and the injection unit 3 are connected via a hinge 1 1. Furthermore provided between the drive unit 2 and the injection unit 3 is a hydraulic cylinder 12 which, when its length is increased in comparison with the length shown in figure 2, causes the injection unit 3 to hinge clockwise about the hinge 1 1 , causing the roller drum 10 to move clear of the ground 13 over which the tracks 5 are moving. This makes it easier to make turns, for example 180 degree turns at the end of a swath.

Using the injection unit 3, fibres can be inserted into the ground 13. The injection unit 3 comprises (see also figure 3) a frame which comprises, inter alia, uprights 37, longitudinal girders 38 and cross members, so that the frame can be regarded as a cage construction. As shown in figure 3, the height of the injection unit 3 is greater than the length. Alternatively, the length may be greater than the height. The width of the injection unit 3 (perpendicular to the plane of the drawing in figure 3) is of course strongly connected with the number of fibres 43 that can be inserted into the ground by means of the injection unit 3. The injection unit 3 further comprises a conveying device for conveying the fivers relative to the frame from rolls 14 to insertion positions above the ground 13, from which insertion positions the fibres are inserted into the ground, as will become clear hereinafter. The rolls 14 are provided on either side of the cage-like frame within the housing 15 which is supported by the frame and which covers the upper side of the frame. The conveying means comprise, inter alia, a guide hose for each roll 14, into which the fibres 43 being unwound from the respective rolls 14 are introduced to be delivered in a horizontal line that extends perpendicular to the direction of movement 59 to the area indicated by the arrow 16 in figure 3.

The conveying device further comprises two endless conveyor chains 21 , which are each made up of identical links 22. The conveyor chains 21 are provided on the sides of the frame of the injection unit 3, spaced about 1 .8 m apart. Four sprockets 23a, 33b, 23c, 23d are provided for each conveyor chain 21 , which sprockets are rotatably mounted to uprights 37 of the frame. The sprocket 23a can be driven, via a drive belt 19, by a driving motor 25, which is likewise mounted to an upright 37 of the frame. The sprockets 23a - 23d are arranged in a rectangular pattern, so that each of the conveyor chains 21 also extends in a substantially rectangular path.

The two conveyor chains 21 are interconnected via connecting elements 33 (see also figure 7). Each of the connecting elements 33 comprises a rectangular connecting plate 24 and, at the corner points of the plate 24, two connecting strips 25 each provided with two slots 26 and two connecting strips 27 provided with a through hole. Provided in the connecting plates 24 are a plurality of aligned slotted holes 27, which extend parallel to and between the rows of clamping elements 41 , 42 (yet to be discussed). Each connecting element 33 further comprises a hinge bracket 28 for each connecting strip 25 and the hinge bracket 29 for each connecting strip 27. A hinge pin 30, 31 extends between two legs of the hinge brackets 28 and the hinge brackets 29. The connecting strips 25, 27 extend between the two legs of the associated hinge bracket 28, 29, with the associated hinge pins 30, 31 extending through the slots 26 and through the through hole in the respective connecting strip 27, respectively. The hinge brackets 28, 29 are connected by means of a link 22, to which end each link 22 is provided with a transverse connecting plate 32.

Instead of effecting the connection between the clamping elements 41 , 42 by means of a connecting plate 24, it would also be possible to realise the connection by means of two connecting strips extending directly opposite each other, or at least near and parallel to the two chains 21 , on two opposite longitudinal sides. Thus a rectangular area would remain open between the clamping elements 41 , 42 and the two connecting strips. This area could be utilised for moving a positioning plate having the same shape as the recess or being smaller up and down when the two clamping elements 41 , 42 in question are in a lower position, in which the fibres 43 held by the clamping elements 41 , 42 can be pressed into the ground by pins 72. The positioning plate could be provided with holes, for example in the form of slotted holes 78, directly below the pins 72, through which the pins 72 move during their up and down movement. The positioning plate would be in a neutral position, under the clamping elements 41 , 42 while the chains 21 are being driven. The neutral position would be such that the positioning plate would be located outside the path of the chains 21 , the clamping elements 41 , 42 or any other part that moves along with the chains 21 . Once the chains 21 are stationary, the positioning plate would move upward to a position in which the positioning plate abuts the bottom side of the fibres 43. This would lead to a more reliable engagement of the fibres 43 by the pins 72. The positioning plate would in any case return to the neutral position before driving of the chains 21 is resumed. In the interim the positioning plate could be moved downward until it makes contacts with the ground or is positioned closely above the ground. The positioning plate would in that case have to take up this position at the moment when the pins move upward again. The positioning plate can thus offer resistance against the ground moving upward along with the pins. This may be advantageous in particular if the upper side of the ground is formed by sods that do not properly connect to the underlying soil yet. The use of such a positioning plate would also be possible without there being any question of a rigid connection between the clamping elements 41 , 42.

Two links 22 are present between the links 22 to which the hinge brackets 28, 29 associated with a connecting element 33 are attached. Furthermore, a link 22 to which a hinge bracket 29 is attached is pivotally connected to a link 22 to which a hinge bracket 28 for an adjacent connecting element 33 is attached. The use of shorter or longer (seen in the longitudinal direction of the chains 21 ) connecting elements 33 that extend along three or five links 22, for example, enables the device 1 to switch over to the insertion of fibres of a different length, as will become clearer hereinafter.

The connecting elements 33 further comprise two parallel horizontal rows of clamping elements 41 , 42. The row in question extends perpendicular to the direction of movement 59, and the clamping elements 41 and the clamping elements 42 in a row are spaced apart by a distance that corresponds to the spacing between the fibres being delivered at position 16.

Each of the clamping elements 41 is aligned with a clamping element 42, so that pairs of clamping elements 41 , 42 between which fibres 43 can be clamped are provided. Each of the clamping elements 42 comprises a clamping strip 44, which is welded in place on the connecting plate 24, and a movable clamping strip 45. The movable clamping strips 45 are interconnected via a connecting strip 46. A guide section 34 is provided for guiding a reciprocating horizontal movement of the connecting strip 46 with the associated clamping strips 45, which guide section is rigidly connected to the plate 24. The connecting strip 46 is provided with a stop plate 47 at one end. A hole is provided in the stop plate 47, through which a guide shaft 48 extends. On the outer side of the stop plate 47, the guide shaft 48 is provided with a retaining collar 49. At the end opposite the collar 49, the guide shaft 48 is provided with the front (seen from the stop plate 47) fixed clamping strip 44. A compression spring 50 is provided under the guide shaft 48 between this first fixed clamping strip 44 and the stop plate 47. The action of the compression spring 50 causes the movable clamping strip 45 of a clamping element 41 to press against the associated fixed clamping strip 44, making it possible to clamp a fibre 43 between the fixed clamping strip 44 and the movable clamping strip 45.

The clamping elements 41 are configured similarly to the clamping elements 42, more specifically comprising a fixed clamping strip 51 and a movable clamping strip 42, therefore, which movable clamping strips 52 are fixedly connected to the connecting strip 53 provided with a stop plate 54 at the end thereof, which connecting strip 53 is guided by the guide section 39.

According to an alternative embodiment for the clamping elements 41 , 42, use may also be made of clamping elements which each comprise two rows of block-shaped clamping portions. As is the case with the clamping elements 41 , 42, the rows extend transversely to the fibres 43, seen in the longitudinal direction of the rows. The block-shaped clamping portions may form part of one single component, for example made by machining. The number of clamping portions of each row is greater than the number of side-by-side fibres 43. Each of the fibres extends between two adjacent blocks of each of the two rows. According to the alternative embodiment, the clamping elements further comprise a pin for each of the fibres 43, which, in a neutral position thereof, is located between two opposite block-shaped portions of two different rows. The pins can be moved jointly, parallel to the longitudinal direction of the rows, from the neutral position to a clamping position. During such movement the fibres 43 are carried along by the pins and passed over part of the circumference of the pins. In the clamping position, each of the fibres 43 is clamped between a pin on the one hand and two facing corner edges of two opposite block-shaped clamping elements associated with two different rows on the other hand. Unlike the situation in which clamping elements 41 , 42 are used, the fibres 43 do not retain their straightness upon being clamped but form a loop-shaped turn around the pins, with each of the fibres 43 being clamped at two discrete positions.

By making use of a cam body 55 in the path of the stop plates 47 and 54, the stop plates 47 and 54 can be pushed in the direction of the associated clamping elements 41 , 42 against the spring action of compression springs 50, 56, as a result of which the movable clamping strips 45, 52 of the associated fixed clamping strips 44, 51 are moved and the clamping engagement of the springs 43 in the clamping elements 41 , 42 can be released, or space can be created between the respective clamping strips 44, 45 and 51 , 52 for positioning a fibre 43 therebetween so as to realise a clamping engagement as soon as the contact between the cam body 55 and the stop plates 47, 54 is lost. Said latter clamping engagement of each of the fibres 43 is effected below position 16 in figure 3 causing each of the clamping elements 41 , 42 associated with the connecting element that is indicated by numeral 33' in figure 3 to clamp a fibre 43. The cam body 55 has such a length and is positioned such that the clamping elements 41 , 42 are opened shortly before the clamping elements 41 , 42 move into the path of the fibres 43, as a result of which the fibres 43 move between the clamping strips 44, 45 or 51 , 52. The clamping elements 41 , 42 will then close again as a result of the stop plates 47, 54 coming clear of the cam body 55. The cam body 55 may either be rigidly connected to the frame of the injection unit 3, as may for example be useful upon introduction of the fibres 43 into the clamping elements 41 , 42, or be movable, as is for example shown in figures 6 and 7.

Directly below the level of the connecting element 33' in figure 3, the injection unit 3 is provided with a cutting unit 61 (see also figures 9-1 Ob) at the rear side (seen in the direction of movement 59) of the injection unit 3. The cutting unit is of the band saw type and comprises a band saw 62, which is passed over four pulleys 63a, 63b, 63c, 63d that are rotatably mounted to a rectangular framework 64. The pulleys 63a - 63d are also arranged in a rectangle, so that the band saw 62 has an upper part that extends between the pulleys 63b and 63c and a lower part that extends between the pulleys 63d and 63a, which lower and upper part extend parallel to each other and which have a length just a little greater than the length of the rows of clamping elements 41 and 42 on each of the connecting elements 33. A driving motor 65 mounted to the framework 64 is provided for driving the band saw 62, which driving motor is connected to the pulley 63a via a transmission 66. The distance between the upper part and the lower part of the band saw 62 corresponds to the centre-to-centre distance between four links 22. The whole of, inter-alia, the band saw 62, the four pulleys 63a-63d, the framework 64, the driving motor 65 and the transmission 66 is protected by a cover 57 that is mounted to the framework 64.

The dimension of the connecting plate 24, seen in the longitudinal direction of the chains 21 , has been selected to be slightly shorter than the centre-to- centre distance between four links 22, so that there is some space between two connecting plates 24 of two adjacent connecting elements 33. The cutting unit 61 is configured to operate within this space.

The cutting unit 61 is connected to the frame of the injection unit 3 via a parallelogram construction 67. More specifically, one side of the parallelogram construction 67 is connected to the upright parts of the framework 64, whilst the opposite part of the parallelogram constructions 67 engages uprights 37 of the frame of the injection unit 3. Furthermore, a cylinder 68 is provided between the parallelogram construction 67 and the frame of the injection unit 3, by means of which the cutting unit 61 can be moved to and fro between a non-operative position as shown in figures 3 and 10a and an operative position as shown in figure 10b. In the operative position, the upper and the lower part of the band saw 62 extend exactly at the upper side of a connecting element 33 and exactly at the bottom side of the connecting element 33, respectively, so that the fibres 43 being clamped by the clamping elements 41 , 42 can be cut loose and short lengths of fibre 43 are formed, the length of which corresponds to the distance between the upper part and the lower part of the band saw 62.

Because the fibres 43 have been cut by the cutting unit 61 , the connecting elements 33 can make a 90 degree turn at the pulley 23b, with the vertical orientation of the fibres changing into a horizontal orientation of the fibres 43. In this turn, the slots 26 in the connecting strips 25 move along the hinge pins 30 associated with the hinge brackets 28.

The cutting unit 61 may also comprise other means for effecting the reciprocating movement between the non-operative position and the operative position, wherein the movement in question takes place perpendicularly to the fibres 43, for example. The position 16 at which the fibres are introduced may furthermore be located on the side of the injection unit 3 opposite the cutting unit 61 , so that a reliable clamping engagement of the fibres 43 by the clamping elements 41 , 42 is obtained already at the moment when cutting of the fibres 43 by means of the cutting unit 61 takes place. The cutting unit 61 may also be fitted with cutting means other than the band saw 62, for example with two pairs of two circular knives which can be driven for rotation about vertical axes of rotation and which are movable transversely to the plane of the drawing in figure 3. The cutting unit 61 may also be provided at the upper side of the injection unit 3. The injection unit 3 further comprises two injection devices 71 which can operate independently of each other. Each injection device 71 comprises a row of pins 72. The pins are provided at the bottom side of a connecting beam 73, which connecting beam 73 can be moved up and down between an upper position, in which the lower ends of the pins 72 extend above the ground 13 again, and a lower position, in which the lower ends of the pins 72 are inserted into the ground 13. The up-and-down movement is effected by means of a crank connecting rod mechanism 75. The injection devices 71 further comprise a driving motor 76 connected to an upright 37 of the frame of the injection unit 3, which drives the associated crank connecting rod mechanism 75 via a drive belt 77. Alternatively, a driving motor such as the driving motor 76 may be connected directly to the crank connecting rod mechanism, i.e. without use being made of a transmission. It is furthermore possible in that case for the driven shaft of the driving motor to extend parallel to the direction of movement 59, for example in order to thus create space to make it easier to replace or perform maintenance on the pins 72.

As appears from figure 3, the pins 72 of the two respective injection devices 71 are positioned directly above the slotted holes 78 that are provided in the connecting plates 24 (see figure 7). During the downward stroke of the pins 72, the pins 72 carry along the fibres 43 being clamped between a pair of clamping elements 41 and 42 through the slotted holes 78 and insert them into the ground 13. During the downward movement of the pins 72, the clamping engagement of the respective fibres 43 by the clamping elements 41 , 42 is released as a result of cylinders 79 (figure 7) being activated. The cylinders 79 are connected to a cam body 55 via a rod mechanism 90, which cam body can thus be operated to be in contact or not in contact with a stop plate 47, 54. When contact is made, the stop plates 47 and 54 will be forced in the direction of the associated clamping elements 41 , 42 and the clamping elements 41 , 42 in question will open, therefore. The timing of this is selected so that this will take place at the moment when or very shortly after the lower ends of the pins 72 come into engagement with the fibres 43. To realise a good engagement of the fibres 43 by the pins 72, the lower ends of the pins 72 are provided with a V-shaped groove.

During the retracting movement of the pins 72, the fibres 43, folded in half, remain behind in the ground 13. The spacing between the pins 72 associated with the two different injection devices will in that case be selected so that the pins associated with the rear (seen in the direction of movement 59) injection device 71 will insert the fibres into the ground at positions located between the positions where fibres 43 have already been inserted in the ground 13 by means of the front injection device 71 .

In the area underneath the injection devices 71 , the chains 21 and thus the fibres 43 will move in the same direction as the direction of movement 59 of the vehicle 1. Alternatively, the directions in question could be opposed to each other, in which case the cutting unit 61 could be located at the front of the injection unit 3, for example.

The injection devices 71 are provided entirely on the inner side of the endless conveyor chains 21 . Between the two injection devices 71 a space 80 is available, so that an operator 99 will have easy access to the two injection devices 71 within the cage-like frame and will be able to quickly correct any malfunctions or perform maintenance. Also refer to figure 4b in this connection.

The injection unit 3 may further comprise means, for example in the vertical rising part of the path of the conveyor chain 21 (i.e. on the left in figure 3), for removing any fibres that have unexpectedly not been engaged by the pins 72, because such fibres 43 might otherwise cause malfunctions. A blowing device or a finger that moves in horizontal direction perpendicular to the plane of the drawing in figure 3 in the area between a pair of clamping elements 41 , 42 may be considered in this connection. It is advantageous in that regard to open the clamping elements 41 , 42 so as to make it easier to remove any fibres 43 that have remained behind.

In use, the conveyor chain 21 moves in steps, the size of the steps equalling the spacing between two successive connecting elements 33. While the conveyor chain is stationary, the cutting device 61 as well as the two injection devices 71 are active. It is furthermore advantageous if also the aforesaid removing means are active while the conveyor chain is stationary.

The injection unit 3 further comprises a platform 91 on both longitudinal sides, which platforms can be swung up so as to reduce the width of the injection unit 3 during road transport. From the lowered platforms 91 , the operator 99 has easy access to the interior of the cage-like frame of the injection unit 3, more specifically in particular to the aforesaid space 80 between the injection devices 71 . To make such access possible, the housing 15 is provided with a recess 93 on both longitudinal sides of the injection unit 3. For the sake of safety, the injection unit 3 is provided with a covering 94 on both longitudinal sides, for example in the form of a mesh, which covering can be removed. On the side facing the drive unit 2, the injection device 3 further comprises a raised platform 95 above the front sprockets 4. Standing on said platform, the operator will have a good view of the introduction of fibres 43 into the clamping elements 41 , 42 and of the cutting device 61 .

The invention is not limited to the embodiment as described above with reference to figures 1 -1 Ob. Countless variants are conceivable, for example in which a combustion engine drives the vehicle, in which only three sprockets are provided for each conveyor chain 21 , so that the conveyor chain 21 moves in a triangular path, in which shorter conveyor chains 21 are used, so that the device will be more compact and lighter, in which only one injection device 71 or, on the contrary, more than two injection devices are provided, in which a different type of endless flexible conveyor element, such as a toothed belt, is used instead of conveyor chains 21 , and/or in which a different type of pulley means, such as a strip- shaped, for example, (chain) guide or a guide roller is used instead of sprockets 23, and/or in which the clamping elements of a pair of clamping elements are not rigidly interconnected.

An example of the latter embodiment is shown in figures 1 1 and 12, which are comparable to figures 5 and 6. As shown in figures 1 1 and 12, two connecting strips 24' are used instead of a single connecting plate 24. Each connecting strip 24' is connected to a link 22 of the chain 21 at the ends thereof. Each connecting strip 24' is provided with a single row of clamping elements 41 ' or with a single row of clamping elements 42'. The clamping elements 41 ' and 42' can be operated in a similar manner as the clamping elements 41 , 42, using a cam body 55' which itself may be operated via a rod mechanism 90'. In contrast to the situation shown in figures 5 and 6, the clamping elements 41 ' and 42' are in line with the two chains 21 , seen in horizontal direction perpendicular to the conveying direction 4, so that the fibres 43 move in a path comparable to that of the chains 21 instead of in a larger path as shown in figures 5 and 6, in which the clamping elements 41 and 42 are located on the outer side of the endless path of the conveyor chains 21 , seen in horizontal direction perpendicular to the conveying direction 4.

According to a further variant, facing clamping elements of adjacent pairs of clamping elements are rigidly interconnected, but the two clamping elements of each pair of clamping elements are not rigidly interconnected. The embodiment of figures 1 1 and 12 could for that purpose be adapted by rigidly interconnecting the two connecting strips 24' that are located relatively close together in the centre of figure 1 1 and accordingly rigidly interconnecting the other pairs of two connecting strips 24' that are located relatively close together. In order to make it possible to make turns, use could be made of slide connections, for example comprising slots 26 and pins 30 (see figure 8).