FR2823644A1 - Method for destroying weeds uses burner with deflector at its base which generates layer of flame at angle to ground - Google Patents

Abstract

The method for destroying weeds (3) uses a burner (1) with a deflector (5) at its base which generates a layer of flame (8) at an angle of 0 -45 deg to the ground (2). A screen (9) is mounted above this to deflect the top of the flame. An Independent claim is included for the burner.

Description

internal wall of the booster.

  PROCESS FOR THERMAL WEEDING OF PLANTS ON THE GROUND AND

DEVICE FOR IMPLEMENTING IT

  The present invention relates to thermal weeding of plants on the ground and more particularly to weeding using a flame generated by

a burner.

  Such a technique is well known.

  In general, it is implemented according to two main methods. Either the flame, generated for example by an individual burner or a burner burner, is sent directly to the plants, or it is kept away from the plants, which are struck by the hot gas thresholds

from combustion.

  In the first case, the flame in contact with the ground and by blast effect will spread, and by the phenomenon of convection will rise from side to side and

across the burning area.

  The high temperature of the streams which will thus spread and rise, risks causing dogats on the aerial part of the plants located in the desUerbege area, for example vines whose unwanted plants are to be destroyed between the rows and between the vines. This method can therefore only be used on surfaces where all the vegetation they

bear must be destroyed.

  In the second case, it is only the hot combustion gases that are used and channeled for this purpose on the plants to be destroyed. If this method allows a more selective action by saving for example the plants of culture, it is less effective because the temperature of the gases reaching the plants to be destroyed is much lower than that of the generating flame and if we want an action really efficient the poor performance of the system leads to prohibitive consumption and to resort to overpowered burner systems and / or to complex forced ventilation devices, necessarily more bulky, heavy and expensive. The present invention aims precisely to remedy the drawbacks of known systems, in particular in the context of their use in areas o coexist both with harmful soil plants and plants

  culture to be preserved, such as vines in particular.

  To this end, the invention relates to a process for thermal weeding of plants on the ground, in which a thermal source is moved above the ground at a determined speed, characterized in that it consists in generating a flame towards the ground, to burst said flame along a sheet whose general plane forms with the ground an angle of between 0 and 45 approximately and to adapt the geometry of the sheet and / or its direction as a function of the direction of movement of said thermal source and of the area to be weeded. A subject of the invention is also a thermal weeding device for implementing the above process, comprising, mounted on a movable frame, at least one burner or the like supplied by an on-board gas or liquid fuel source and means command / control of the burner, characterized in that it further comprises a deflector forming a flame spreader interposed between the ground and the burner so as to deflect the flame and spread it out according to a tilting sheet by determined relation to the ground and of determined width and a screen deflector substantially parallel to the ground, having an orifice for the passage of the flame and cooperating with the spark gap to press against the ground said sheet

  from the spark gap to the periphery of the screen deflector.

  According to a first embodiment, the spark gap has a conical upper face whose axis is substantially coincident with that of the burner, the screen deflector preferably having a rectangular planar shape, and arranged with its plane interposed between said burner. and the poldle dudlt Aclateur. According to a second mode of rdaNsabon, Federator presents a higher planar face lncUnde AventueRement mobilue and adjustable in incUnaison and odenion by ppo the acne din of eng engeun Following a trolAme mode of rdaNsation, double slope donl a [6te est para "Ale la

  Fengln poet's displacement dectlon.

  Raising yet another mode of rdaUsatlon, the carrying chAss is provided with two identical sets of weeding each comprising a burner or the like, a deflector-Aclator and a dABector-Acran, the two sets being mounted loose and adjustable so as to adjust their Apartment and / or their

individual posonneme.

  The technique according to the invention provides a burn zone which is perfectly of the same kind as a large vress of Avacuabon of combustion gases at ground level, which does not have any negative effect on the proportion of any cultivation plants being found. proximk6. In addition, from the fak of the work of the dector-Acran the thermal delight above the

burner area is very small.

  Finally, the explosion of the Damme allows the latter to cover a very expected surface area, a high temperature, which increases the time.

  of brOlage and therefore provides remarkable efAcackA and performance.

  Other characteristics and advantages will emerge from the description which

  will follow modes of implementation of the procAd of [invention, descApton given by example only and with reference to the appended drawings on read: - Figure 1 is a diagram illustrating the principle implemented in procAdA of lnveon; - gu 2 e a top view of the epos 1 dposk; - Figures 3 and 4 are similar views ceHes of Figures 1 and 2, illustrating a second mode of implementation of the invention; - Figure 5 illustrates a variant use of the device of Figure 4; - Figures 6 and 7 are views similar to those of Figures 1 and 2, illustrating a third embodiment of _uvre of the invention; - Figure 8 is a sectional view along line Vlli-VIII of the device of Figures 6 and 7; - Figure 9 is a schematic side elevation view of a weed control device according to the invention in semi-mounted version coupled to a tractor; - Figure 10 is a top view of the assembly of Figure 9; - Figures 11 and 12 illustrate the use of a machine of the type of Figures 9, 10 for the desUerbage of two planting lines in the row; - Figure 13 is a schematic view in plunging perspective of a weeding device according to the invention in manual displacement version 1 5, and - Figure 14 is a side elevational view of the machine of Figure 1 3. In FIGS. 1 and 2, there is shown diagrammatically at 1 an individual burner directed towards the ground 2 covered with plants 3 to be destroyed, the axis of the burner nozzle being substantially perpendicular to the ground. The burner 1 is connected, via an adjustable mono-regulator 4, to a source of fuel, gaseous or

liquid, not shown.

  Between the burner 1 and the ground 2 is interposed a deflector 5 acting

  flame spreader 6 generated by burner 1.

  The spark gap 5 is a conical metal part, the point 6 is substantially in the axis of the burner, and the flame 7 explodes into a conical sheet 8 at the height of the spark gap. The sheet 8 is oriented by the inclined face of said spark gap 5 in a direction, symbolized by the arrow F in the figure

  1, which forms an angle with the ground of about twenty degrees.

  Beyond the spark gap 5, the conical sheet 8 is confined in a space of low height delimited between the ground and a flat screen deflector 9 arranged

  parallel to the ground 2, at a suitable height, adjustable.

  The screen deflector 9 is substantially at the height of the point 6 of the cone of the spark gap 5 and has a circular orifice 10 centered on the point 6 and of

  diameter slightly greater than the diameter of the spark gap 5.

  The screen 9 has a generally rectangular shape. In 11 is shown schematically the ignition and safety device of the burner 1. The set of members 1, 5, 9, 11 is mounted on a chassis of a self-propelled machine, towed or moved manually, according to the envisaged uses. The machine is moved for example along arrow A, the deflector assembly 5, 9 burner 1 being adjustable in height with respect to the ground, at the

  like the cutting device of a mower for example.

  As the machine advances, the plants 3, for example herbs, are burnt, the burned area being represented at B in FIG. 2, however, the burned area is shown along a ring ZB delimited by the conical sheet 8, beyond the spark gap 5, over its entire periphery. The width of the screen 9 corresponds substantially to the outside diameter of the burning zone ZB. The combustion gases escape and rise (arrows G) beyond the screen 9, on the four sides of the latter. Due to the existence of the screen 9 above the burning zone ZB, the thermal radiation above the burner 1 is weak and insufficient to damage any crop plants located near the weeding device. Similarly, the bursting of the flame G by the deflector 5 accelerates the evacuation of the combustion gases at ground level and these gases, diffused in all directions and which have time to cool before escaping from the outside the screen 9 due to the lengthening of their route under said screen 9, no longer present a danger to the aerial parts of the

any crop plants.

  Such a device is effective because the spark gap 5 increases the floor area

  covered by the flame so that a larger amount of plants is.

  at the same time, in contact with a high temperature flux.

  The efficiency of the device is thus substantially improved in

  comparison with traditional thermal weedkillers.

  The embodiment of Figures 3 and 4 differs from that of Figures 1 and 2 by the shape of the spark gap 5 'which is a simple rectangular inclined plane, the inclination being towards the rear of the device relative to the direction of displacement A. The spark gap 5 'bursts the flame 6 along a flat sheet 8' whose plane F 'forms with the ground an angle of the same order as that of the arrow F of the

  Figure 1, about twenty degrees.

  The screen 9 'is pierced with a suitable orifice 10', that is to say rectangular in correspondence with the shape of the spark gap 5 ', the lower part of the latter extending substantially under the screen 9 '' so as to channel the

8 'burn sheet.

  The burn zone ZB '(Figure 4) is approximately shaped

1 5 rectangular.

  The burning width of the device is substantially identical to that of the previous device and determined by the dimension (taken perpendicularly

  to direction A) of spark gap 5 '.

  FIG. 5 illustrates a variant of the device of FIG. 4 in which the spark gap 5 "is a rectangular plane inclined but laterally and no longer towards the rear of the machine. The rectangular orifice 10" of the screen 9 " is willing

  Consequently. The burn zone ZB 'is lateral.

  In the embodiment of FIGS. 6 to 8, the spark gap 5 "'is rectangular and has an upper face in the form of a roof with a double slope, the central edge 12 of which is parallel to the direction A. The orifice 10"' of the screen

  9 "'is rectangular, corresponding to the shape of the spark gap 5"'.

  The flame 6 is split into two opposing, symmetrical layers 8a, 8b directed towards the two lateral flanks of the machine. The inclination of the two upper faces of the spark gap 5 "'is similar to that of the previous spark gaps (5,

5 ', 5 ").

  The burn zones ZB "'are double and symmetrical.

  Figures 9 and 10 show a weed control device according to the invention in semi-mounted version, moved by means of a three-point hitch

points by a tractor 13.

  The device comprises two separate, identical assemblies 14 and 15, articulated on a chassis 16 carried on which is fixed a reservoir 17 of

  fuel for example gas under pressure.

  Each assembly 14, 15 rests on the ground by a roller 18 at the rear of the assembly and comprises for example a spark gap such as the spark gap 5 in FIGS. 1 and 2, the heat-treated area being a strip 19 in the axis

of each set 14, 15.

  The assemblies 14, 15 are advantageously mounted so as to be able to adjust their spacing (double arrow 20) and / or their angular orientation (double arrow 21), as illustrated by the dashed assemblies 14 ', 1 5'. Figures 11 and 12 illustrate the use of a machine such as that of Figures 10, 1 1 to treat in one pass two planting lines

parallels P1 and P2.

  For this purpose, the spark gaps of the two release assemblies 14 "and" are of the spark gap type 5 "of FIG. 5 for lateral treatment.

(ZB burn zone ").

  Figures 13 and 14 illustrate a manual displacement version of the

device of the invention.

  On a frame 22 mounted on wheels 23 are arranged a reservoir 24 for example of compressed gas, a burner 1, a spark gap of the spark gap type 5 'of FIGS. 3 and 4 and a screen 9'. The burner is hidden under a protective casing 25 which also makes it possible to recover calories ensuring, during very cold outside temperatures, the heating of the gas bottle

24, thus avoiding icing.

  At the rear of the chassis 22 is arranged a system of handles 26 for

  push and steer the device. The spark gap 5 'directs the sheet 8' forwards.

  In general, the various spark gaps of the various embodiments can be mounted adjustable in position relative to the burner 1, or even in orientation relative to the direction of operation of the weeding apparatus. The inclination of the burning blanket (8, 8 ', 8a, 8b) can vary within an inclination range of from 0 to 45 approximately. The screen deflector can also be mounted adjustable in position relative to the spark gap. The burner 1 can be simple and individual or multiple and formed

a ramp for example.

  It should finally be noted that the device of the invention can of course be used for other tasks than weeding, for example sterilization of the soil, destruction of vermin, drying, dogelage or denigrating of

floors or surfaces.

Claims (6)

  1. A method of thermal weeding of plants (3) on the ground (2), in which a thermal source (1) is moved above the ground at a determined speed, characterized in that it consists in generating a flame (6) towards the ground (2) to burst said flame along a sheet (8, 8 ', 8 ", 8a, 8b) whose general plane forms with the ground an angle between 0 and 45 approximately and to adapt the geometry of the tablecloth and / or its direction as a function of the direction of movement of said thermal source (1) and of the zone to be weeded. 2. Device for implementing the method according to claim, comprising, mounted on a movable frame, at least one burner and / or the like supplied by a source of gaseous or liquid fuel on board and means for controlling / controlling the burner, characterized in that it further comprises a deflector forming a flame spreader (5, 5 ', 5 ", 5"') interposed between the ground (2) and the burner (1) so as to deflect the flame (6 ) and spread it out according to a sheet (8, 8 ', 8 ", 8a, 8b) of inclination relative to the ground determined and of determined length and a screen deflector (9, 9', 9", 9 "') substantially parallel to the ground, having an orifice (10, 10', 10", 10 "') for the passage of the flame (6) and cooperating with the spark gap (5, 5', 5", 5 "') to press said sheet (8, 8', 8", 8a, 8b) against the ground from the spark gap   to the periphery of the screen deflector (9, 9 ', 9 ", 9"').   3. Device according to claim 2, characterized in that the spark gap (5) has a conical upper face whose axis is substantially coincident with that of the burner (1), the screen deflector (9) being rectangular in shape preferably and arranged with its plane interposed between led it   burner (1) and the tip (6) of said spark gap (5).   4. Device according to claim 2, characterized in that the spark gap (5 ', 5 ") has a flat inclined upper face possibly movable and adjustable in inclination and orientation relative to the direction of movement (A) of the carrier.   5. Device according to claim 2, characterized in that the spark gap (5 "') has an upper face in the form of a double slope roof whose edge   (12) is parallel to the direction of movement (A) of the carrier.   6. Device according to one of claims 3 to 5, characterized in that   that the supporting frame (16) is provided with two identical sets (14, 15; 14 ", 15") of weeding each comprising a burner (1) or the like, a deflector-spark gap (5, 5 ', 5 ", 5 "') and a screen deflector (9, 9', 9", 9 "'), the two assemblies being mounted mobile and adjustable so as to adjust their   spacing and / or their individual positioning.