VARIABLE GRASS-LENGTH INJECTION

Abstract

Yarn injection device for injecting yarn sections into a substrate, wherein the yarn injection device comprises:a yarn storage for holding a number of spools with yarn,a feeding device configured to feed lengths of yarn to an injection unit, the feeding device comprising: ?a number of yarn tubes, each yarn tube defining a yarn channel configured to accommodate a respective yarn, ?a number of cutting devices located being configured to cut a number of yarn sections,the injection unit comprising: ?an injection needle guide defining a number of first passages extending over a vertical distance and a number of second passages extending over a horizontal distance, ?a number of moveable injection needles configured to pass through the first holes of the injection needle guide, wherein yarn sections in the yarn tubes located below the moveable injection needles are injected into the substrate when the moveable injection needles move downward through the injection needle guide, ?at least one needle actuator configured to move the number of moveable injection needles,a fluid flow assembly, wherein at least one fluid communication channel extends between the injection needle guide and the depressurized or pressurized compartment, wherein the fluid flow assembly is configured to create a flow of fluid through each fluid communication channel, each injection needle guide and each yarn tube in order to apply a drag force on the yarns and move the yarns through the second passages in the injection needle guide.

Claims

1.-59. (canceled)

60. A yarn injection device for injecting yarn sections into the ground, wherein the yarn injection device comprises: a yarn storage comprising a number of spool holders for holding a number of spools with yarn, a feeding device configured to feed lengths of yarn via respective supply paths from the storage to an injection unit, the feeding device comprising: a number of yarn tubes, each yarn tube defining a yarn channel configured to accommodate a respective yarn, and a number of cutting devices located at a side of the number of yarn tubes and being configured to cut a number of yarn sections from the respective yarns extending from the yarn storage into the yarn tubes, wherein the feeding device is configured to feed an adjustable length of yarn to the yarn injection device, the injection unit comprising: an injection needle guide defining a number of first passages extending over a vertical distance and a number of second passages extending over a horizontal distance, wherein each first passage intersects a respective second passage, and wherein each yarn channel is fluidly connected to a respective second passage, a number of moveable injection needles moveable between an upper needle position and a lower needle position and configured to pass through the first passages of the injection needle guide, wherein when yarn sections in the yarn tubes are located below the moveable injection needles and the moveable injection needles move downward through the injection needle guide, the yarn sections are injected into the substrate, at least one needle actuator configured to move the number of moveable injection needles between the upper needle position and the lower needle position, a fluid flow assembly comprising at least one fluid communication channel and a depressurized compartment having an underpressure, wherein the at least one fluid communication channel extends between the injection needle guide and the depressurized compartment, wherein the supply paths extend from the respective spool holders via the feeding device to the injection unit, and the feeding device is configured to supply the yarns to the injection unit, and wherein the fluid flow assembly is configured to create a flow of fluid through each fluid communication channel, each injection needle guide and each yarn tube in order to apply a drag force on the yarns and move the yarns through the second passages in the injection needle guide, wherein the yarn injection device further comprises a cutting device moving system configured to move the number of cutting devices towards or away from an intersection of the first passages and the second passages.

61. The yarn injection device according to claim 60, wherein the at least one fluid communication channel comprises a channel valve located between the depressurized compartment and the injection needle guide, the channel valve being moveable between an open state and a closed state, wherein in the open state the channel valve allows communication of a fluid flow between the depressurized compartment and the injection needle guide, the number of yarn tubes, and/or the feeding device, and wherein in the closed state the channel valve inhibits communication of a fluid flow between the depressurized compartment and the injection needle guide, the number of yarn tubes, and/or the feeding device, wherein in particular the fluid is air.

62. The yarn injection device according to claim 60, wherein the feeding device is configured to feed an adjustable length of yarn to the injection device, and wherein the device further comprises a cutting device moving system configured to move the number of cutting devices towards or away from the intersection.

63. The yarn injection device according to claim 60, wherein the number of yarn tubes are extendable tubes extending between the injection needle guide and the cutting devices, and wherein the cutting device is moveable with respect to the intersection of the first passages and the second passages to vary the length of the extendable tubes.

64. The yarn injection device according to claim 60, wherein the yarn is not clamped prior to or during cutting.

65. The yarn injection device according to claim 60, wherein the feeding tubes are flexible and/or moveable.

66. The yarn injection device according to claim 60, wherein the fluid flow assembly further comprises a suction pump and a suction buffer tank, and wherein the fluid communication channel is connected to the suction pump and/or the suction buffer tank and the suction buffer tank is the depressurized compartment.

67. The yarn injection device according to claim 60, wherein the injection needle guide comprises a shutter assembly, wherein the shutter assembly is moveable between a closed state and an open state, and wherein in the closed state the shutter assembly closes off the first passages.

68. The yarn injection device according to claim 67, wherein the shutter assembly comprises two sliders and a slider actuator, wherein the slider actuator moves the two sliders between the closed state and the open state, and wherein a first slider is located below the second passages and a second slider is located above the second passages.

69. The yarn injection device according to claim 68, wherein each slider defines a number of slider holes, wherein in the open state of the shutter assembly, the slider holes are substantially aligned with the first passages, and wherein in the open state the moveable injection needles are moveable through the first passages and the slider holes.

70. The yarn injection device according to claim 69, wherein the injection needle guide comprises a biased shutter located on a lower side of the hole, wherein a default position of the biased shutter is in the closed state and the biased shutter is configured to be moved into the open state by the downward movement of the moveable injection needles.

71. The yarn injection device according to claim 60, wherein the slider holes and/or the first passages are larger than the moveable injection needle in a direction substantially parallel to the second passages.

72. The yarn injection device according to claim 60, wherein the fluid flow assembly comprises a waste receptacle removably located within the suction buffer tank, wherein the waste receptacle comprises a plurality of holes, wherein the waste receptacle is configured to collect and retain waste entering the suction buffer tank from the fluid communication channel.

73. The yarn injection device according to claim 60, wherein each of the number of cutting devices comprises a yarn passage and a moveable knife, wherein a yarn extends from the feeding device through the yarn passage and into a respective yarn tube, wherein the knife is moveable between an open state and a closed state, wherein the knife is configured to cut the yarn at the yarn passage when moved from the open state to the closed state, and wherein the knife closes off the yarn passage in the closed state and inhibits a fluid flow in the yarn tube.

74. The yarn injection device according to claim 60, wherein the yarn injection device further comprises a moving assembly, the moving assembly comprising a frame and wheels and/or tracks mounted to the frame, configured to allow the yarn injection device to move over a surface, wherein the suction buffer tank and the suction pump are located left of the injection needle guide and a drive system of the moving assembly is located right of the injection needle guide in side view to create an even weight distribution.

75. A method for injecting yarn section into the ground using a yarn injection device comprising: a yarn storage comprising a number of spool holders for holding a number of spools with yarn, a feeding device comprising: a number of yarn tubes configured to accommodate yarn, and a number of cutting devices, wherein the feeding device is configured to feed an adjustable length of yarn to the yarn injection device, and an injection unit comprising: an injection needle guide defining a number of first passages extending over a vertical distance and a number of second passages extending over a horizontal distance, wherein each first passage intersects a respective second passage, and wherein each yarn channel is fluidly connected to a respective second passage, a number of moveable injection needles, at least one needle actuator, and a fluid flow assembly comprising at least one fluid communication channel and a depressurized compartment having an underpressure, wherein the at least one fluid communication channel extends between the injection needle guide and the depressurized compartment, wherein the yarn injection device further comprises a cutting device moving system configured to move the number of cutting devices towards or away from an intersection of the first passages and the second passages, the method defining a cycle comprising the steps: a) supplying yarn from the yarn storage along a supply path to the feeding device, b) feeding a length of yarn into the number of yarn tubes with the feeding device, c) communicating a fluid flow to the number of yarn tubes to apply a drag force on the yarn and feed the yarn through the number of yarn tubes and the number of second passages of the injection needle guide, d) cutting the yarn into yarn sections with the number of cutting devices, wherein the yarn sections are at least partially located in the number of yarn tubes and the injection needle guide, e) moving the number of moveable injection needles downwards through the number of first passages, wherein the yarn sections are engaged by the number of moveable injection needles and are inserted in a substrate below the injection needle guide, the method further comprising: adjusting the length of yarn which is fed to the yarn injection injection device, and moving the number of cutting devices towards or away from an intersection of the first passages and the second passages by the cutting device moving system.

76. The method according to claim 75, wherein the at least one fluid communication channel comprises a channel valve that is moveable between an open state and a closed state, wherein prior to step d) the channel valve is moved from the open state to the closed state, wherein the cycle further comprises the steps: f) moving the moveable injection needles upwards through the first passage, wherein the yarn sections are left in the substrate below the injection needle guide, g) moving the cutting device to the open state and moving the channel valve to the open state, h) repeating step a)-e), wherein the yarn injection device comprises a moving assembly, wherein the yarn injection device is moved over a lateral distance after step f) and before a subsequent step e), and wherein steps g)-d) are executed while the yarn injection device is moving.

77. The method according to claim 75, wherein prior to step d) the moveable injection needles are moved downwards to an intermediate position, wherein in the intermediate position, the moveable injection needles exert a friction force on the yarn keeping the yarn in place during step d).

78. The method according to claim 75, wherein the fluid flow assembly further comprises a suction pump and a suction buffer tank, wherein the at least one fluid communication channel is connected to the suction pump and/or the suction buffer tank, and wherein the fluid flow assembly creates an underpressure and/or a fluid flow in at least one of the feeding device, the number of yarn tubes, and the injection needle guide during step c).

79. The method according to claim 75, wherein the injection needle guide comprises a shutter assembly that is moveable between a closed state and an open state, wherein in the closed state the shutter assembly closes off the first passage, and wherein the shutter assembly is moved to the open state prior to step e).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0121] FIG. 1 shows an isometric view of a yarn injection device.

[0122] FIG. 2 shows an isometric view of a yarn injection device.

[0123] FIGS. 3A and 3B show a side view of a yarn injection device.

[0124] FIGS. 4A, 4B, and 4C show isometric views of part of the feeding device.

[0125] FIGS. 5A and 5B show the injection needle guide and part of the feeding device.

[0126] FIGS. 6A, 6B and 6C show the injection needle guide and part of the feeding device.

[0127] FIGS. 7A and 7B show the injection needle guide together with a moveable injection needle.

[0128] FIG. 8 show a side view of the yarn injection device comprising a moving assembly.

[0129] FIG. 9 show an isometric view of the yarn injection device comprising a moving assembly.

DETAILED DESCRIPTION OF THE DRAWINGS

[0130] In FIGS. 1, 2, 3A, and 3B, a general overview of a yarn injection device 10 for injecting yarn sections 1 into a substrate 2 is shown.

[0131] A feeding device 20 is configured to feed lengths of yarn via supply paths 22 from spool holders of a yarn storage (depicted in FIGS. 8 and 9) via the feeding device and to an injection unit 30. To do so, the feeding device comprises a number of yarn tubes 24 that each define a yarn channel that is configured to accommodate yarn that is to be fed to the injection unit 30. In operation, when a desired length of yarn has been fed into and through the injection unit 30, a number of cutting devices 26 that are located at a side of the number of yarn tubes cut a number of yarn sections 1 from the yarn extending from the yarn storage into the yarn tubes.

[0132] When the yarn sections have been cut, the injection unit injects them into the substrate. To this end, the injection unit comprises an injection needle guide 32 that guides a number of moveable injection needles 38 into the substrate. Besides defining a number of first passages 34 that extend over a vertical distance 341 and are intended to guide the number of moveable injection needles, the injection needle guide 32 also defines a number of second passages 36 that extend over a horizontal distance 361. The second passages 36 are intended to guide yarn through the injection needle guide 32 and to below the number of moveable injection needles. For this reason each first passage intersects a respective second passage and each yarn channel us fluidly connected to a respective second passage.

[0133] In the side views of FIGS. 3A and 3B, the injection needle 38 is located above the injection needle guide 32 in the upper needle position and the number of yarn tubes 24 is located on the right of the injection needle guide. The area denoted by numeral 98 in FIG. 3A is depicted in detail in FIG. 3B. The number of cutting devices 26 is located on the right of the yarn tubes and can be actuated by a cutting actuator 261, the feeding device 20 is located on the right of the number of cutting devices, and the fluid communication channel 42 is located on the left injection needle guide. The cutting device comprises a knife 266 that is moved with respect to a static part 267 by the cutting actuator 261 to cut the yarn. Here, the knife 266 is moved in a direction normal to the plane of the cross-section. However, other directions are also possible. The fluid communication channel 42 serves the purpose of communicating an underpressure from a depressurized compartment located on the left of injection needle guide 32 to the injection needle guide and the feeding device The depressurized compartment 44 is located on the left of the injection needle guide.

[0134] When a yarn is located below the moveable injection needles, the moveable injection needles can move from an upper needle position to a lower needle position while passing through the holes of the injection needle guide 32. This movement is actuated by at least one needle actuator 37. The yarn sections 1 in the yarn tubes are then injected into the substrate 2 during this movement. In order for the yarn section 1 not to get stuck in the device, a fluid flow assembly 40 comprising at least one fluid communication channel 42 and a depressurized compartment 44 is provided. Here, the fluid flow assembly is located on an opposite side of the injection needle guide 32 relative to the yarn tube 24 and the depressurized compartment has an underpressure. Because the fluid communication channel 42 extends between the injection needle guide 32 and the depressurized compartment 44, a flow of fluid can be created through the fluid communication channel 42, the injection needle guide 32 and the yarn tube 24 in order to apply a drag force on a yarn and move the yarn through the injection needle guide 32.

[0135] Because it would require a lot of energy to keep the depressurised compartment 44 under a constant underpressure while also communicating this underpressure with the outside world via any of the other components, a channel valve 422 is located between the depressurized compartment 44 and the injection needle guide 32. In an open state the channel valve 422 allows communication of a fluid flow between the depressurized compartment 44 and the injection needle guide 32, the number of yarn tubes 24 and/or the feeding device. In a closed state, the channel valve 422 inhibits communication of a fluid flow between the depressurized compartment and the injection needle guide, the number of yarn tubes, and/or the feeding device.

[0136] Since an underpressure is communicated to the injection needle guide 32, when an injection needle moves to an upper position after having injected a yarn section 1 into the substrate 2, a small amount of fluid will be sucked in through the first passage 34. The sucked in fluid will travel to the depressurized vessel and in doing so may suck along some debris (substrate that has attached itself to the injection needle, yarn waste, etc.). In order to prevent this debris to loosely fly around, a waste receptacle 442 is removably located within the depressurized compartment 44. Because the waste receptacle comprises a plurality of holes and acts like a filter, waste entering the depressurized compartment can be collected and retained before being thrown out after removing the receptacle.

[0137] Also, because fluid is not only sucked in through the injection needle 32 but also through other nooks and crannies, the underpressure in the depressurized compartment 44 may drop over time. To overcome this a pump may be connected to the depressurized compartment. A pressure sensor 47 is located within the depressurized compartment and is connected to a control unit 52 that is configured to read out the pressure sensor and to provide a user with pressure data so the user may intervene. The control unit may also control any of the cutting device, the channel valve, the feeding device the shutter assembly 33, the moveable injection needles, and/or the fluid flow assembly. In particular, the control unit is configured to control a cycle, wherein in the cycle, the feeding device is operated to feed lengths of yarn to the injection unit, thereafter the number of cutting device cut the lengths of yarn and the injection needles inject the lengths of yarn in the substrate.

[0138] As one will understand, different substrate conditions may require different injection depths of yarn, e.g. an irrigation pipe may be located close to the surface and requires a smaller injection depth than directly besides the pipe. If the depth of the injection will vary, to create a uniform yarn length above the substrate, the yarn section must be shortened. To be able to adjust the length of the yarn section 1, feeding device 20 can feed an adjustable length of yarn to the injection unit 30. A deeper penetration will require a longer length and a shallower penetration will require a shorter length. Also, the cutting device 26 is moveable along the direction indicated by arrow 263 (see also FIG. 3A) by a cutting device moving system 262 with respect to the intersection of the first passages 34 and the second passages 36 to adjust the cut length of the yarn section. To allow the moving of the cutting device, the yarn tubes 24 are telescoping tubes comprising three sections 242A, 242B, 242C that can slide into one another. The three sections 242A, 242B, 242C have an inner diameter that substantially matches the outer diameter of a subsequent tube to form a tight seal. Further, the yarn tubes 24 are guided by flanges 245 that are connected to guides 246 to allow the telescopic tubes to lengthen and shorten. To be able to operate under a wide variety of substrate conditions, the distance from the cutting device 26 to the intersection is adjustable over a continuous range of preferably 40-300 mm, more preferably 55-350 mm, even more preferably 90-200 mm in a stepless manner. In order to be able to adjust the length of the yarn section 1 and to communicate a pressure from the depressurized compartment 44 to the feeding device, the yarn tubes 24 are extendable. In particular, the yarn tubes are telescoping tubes. As can be seen, no clamping is done and is necessary to be done to be able to cut the yarn section 1.

[0139] Looking at FIGS. 4A, 4B, and 4C, the feeding device 20 is shown independently. The feeding device 20 comprises two rollers 28A, 28B that have a continuous surface and are pressed together by a roller presser 282A, 282B. A roller presser can take multiple forms such as a spring or an actuator. During operation, a first end of a yarn is placed between the rollers and the rollers are driven by a roller actuator 202. The rotation of the rollers 28A, 28B then feeds the yarn to the injection needle guide. By letting the control unit control a number of revolutions of the hollers 28A, 28B the length of the yarn section fed to the injection unit can be controlled. To guide the yarn to the yarn tubes 24, a feeding guide 272 guides individual yarns into feeding tubes 27 that extend to the cutting device. Because the feeding tubes 27 are of a constant length and are flexible, when the cutting device 26 and or the feeding device are moved together or relative to each other a distance between the cutting device and the rollers 28A, 28B along which a yarn extends, remains constant. The feeding device 20 may be located at a distance above the injection needle guide to make it easily accessible to an operator for the operator to place yarn between the rollers. Because the injection needle guide is located close to the ground, if the feeding device would be close to it, an operator would have to bend over to reach it. Therefore, the distance is in the range of 50-150 cm for the operator to easily reach the feeding device.

[0140] Turning to FIGS. 5A, 5B, 6A, 6B and 6C, the cutting device 26 is shown together with the injection needle guide 32. When a pressure is communicated to the injection needle guide 32, the fluid may escape through the first passages 34. To reduce the amount of lost pressure, the injection needle guide 32 comprises a shutter assembly 33 that is moveable between a closed and an open state in which it respectively closes off the first passages 34 and doesn't close off the first passages 34.

[0141] The shutter assembly comprises a first slider located 334A located below the second passages 36 and a second slider 334B located above the second passages 36. Each slider can be moved in a lateral direction by a slider actuator 336 between the closed state and the open state. In the open state, a number of slider holes 338A defined in the first slider 334A and a number of holes 338B defined in the second slider 334B substantially align with the first passages 34 for the moveable injection needles to be moveable through the first passages and the slider holes. In order for the moveable injection pin to be able to pass through the injection needle guide and the sliders, at least the number of slider holes 338A defined in the first slider 334A and the first passages 34 are larger than the moveable injection needle in a direction substantially parallel to the second passages 36. This is schematically depicted in FIG. 6C. Here, the large circular part of the hole 338 allows the needle to pass through and the oval sections extending to the sides accommodate the yarn when the needle passes through the injection needle guide together with the yarn. This allows the injection needle to extend through the slider hole and the first passage together with two ends of the yarn section next to it without jamming.

[0142] In the figures, the feeding tubes 27 have been left away to more clearly show the cutting device 26. The cutting device comprises a yarn passage 264 to which a feeding tube extends. The yarn passage is formed in the static part 267. After the yarn exits the feeding tube, the yarn passes through the yarn passage 264 of the cutting device and into the yarn tube 24 located on the opposite side of the cutting device relative to the feeding tube. A knife 266 is disposed in front of the yarn passages and is moveable between an open state and a closed state by a knife actuator 261. The knife may have the form of a plate with a number of holes 269. Each hole is associated with a yarn passage 264. The holes 269 may be conical. In the open state the holes 269 are aligned with the respective yarn passages 264. In the closed state the holes 269 are non-aligned with the yarn passages. By moving from the open state to the closed state, the knife cuts each yarn in each yarn passage. Because, in the closed state, the knife 266 closes off the yarn passage 264, it inhibits a fluid flow in the yarn tube 24.

[0143] Turning further to FIGS. 7A and 7B, part of the injection unit is shown. In particular, a needle beam 385 is shown located above the injection needle guide 32. In order for the actuators 37 to move all injection needles 38 (of which only one is depicted) simultaneously, all the injection needles 38 are fixed to the needle beam 385. The needles are placed in needles holes 386 that extend through the needle beam. The needle beam 385 further defines fixating holes 381 in which a fixating means such as a screw can be threaded against the injection needle to fix the injection needle 38 to the needle beam 385. When the needle beam is moved in a vertical direction between an upper position and a lower position, the injection needles move through the injection needle guide 32.

[0144] Looking at FIGS. 8 and 9, the yarn injection device further comprises a moving assembly 60 that is connected to the feeding device 20, the injection unit 20, and the fluid flow assembly comprising the depressurized compartment 44 and the fluid communication channel 42. The area denoted by numeral 99 is depicted in detail in FIGS. 3A and 3B. The moving assembly 60 comprises a frame 62 and wheels 64 that are mounted to the frame. When the injection needles have injected yarn sections into the substrate 2, the moving assembly 60 can be used to move the device over a surface of the substrate 2 to move to a subsequent injection location. Here, the yarn injection device can inject a following row of yarns sections.

[0145] Besides being connected to the feeding device 20, the injection unit 30, and the fluid flow assembly, the moving assembly 60 also supports the yarn storage 12. This yarn storage comprises spool holders 122 for holding spools 124 of yarn to store the yarns that are to be fed to the injection unit.

[0146] To create an even weight distribution, the depressurized compartment 44, i.e. the suction buffer tank, and the suction pump 46 are located left of the injection needle guide of the injection unit 30 and a drive system 66 of the moving assembly 60 is located right of the injection needle guide. These parts are relatively heavy and therefore largely contribute to the weight distribution.

[0147] In a not depicted embodiment, the fluid flow assembly comprises a pressurized compartment instead of a depressurized compartment as described above. The pressurized compartment has an overpressure and the fluid communication channel extends between the injection needle guide and the pressurized compartment. The principle of operation and the general lay-out are substantially similar to that described above. The main difference is that the fluid communication channel does not connect to the injection needle guide on the left of the injection needle guide, but may connect to the injection needle guide, the yarn tubes, and/or the feeding tubes on the right side on the injection needle guide.

[0148] Similarly to the underpressure described above, the overpressure will create a flowing fluid passing through the second passage away from the feeding device and will, by exerting a force on the yarn, pull the yarn through the injection needle guide.

[0149] The terms a or an, as used herein, are defined as one or more than one. The term plurality, as used herein, is defined as two or more than two. The term another, as used herein, is defined as at least a second or more. The terms including and/or having, as used herein, are defined as comprising i.e., open language, not excluding other elements or steps.

[0150] Any reference signs in the claims should not be construed as limiting the scope of the claims or the invention. It will be recognized that a specific embodiment as claimed may not achieve all of the stated objects.

[0151] The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0152] White lines between text paragraphs in the text above indicate that the technical features presented in the paragraph may be considered independent from technical features discussed in a preceding paragraph or in a subsequent paragraph.