FR2750619A1 - Rotary mixer for coating grains and seeds - Google Patents

Abstract

A mixer comprises a vessel (1) open at the top (5) and having a polygonal cross-section perpendicular to its longitudinal axis (2), the vessel in use being rotated about axis (2) and oscillated about a different axis (8). Also claimed are use thereof, wherein the vessel is rotated about axis (2) for a time and oscillated about axis (8) for at least some of that time, and application of the mixer to coating of grains and seeds.

Description

 The present invention relates to a mixer for pulverulent products, in particular intended for the treatment of seeds and / or seeds, as well as a method implementing said mixer, and its application to the coating of said seeds and / or seeds.

 Although more particularly developed for such uses, the invention may, in general, be used in all sectors of economic activity in which it is necessary to brew pulverulent products.

 Currently, more and more seeds and / or seeds are, before their use, treated and coated with various products such as, for example, insecticides and / or fungicides. In fact, this process makes it possible to avoid multiplying the spreading of chemicals in the fields once said seeds and / or seeds are in place.

 To obtain such a coating, there are different continuous or discontinuous processes.

 According to continuous processes, said seeds and / or seeds are driven in a given direction, for example, by means of an endless screw, and they are sprinkled during their course of treating product.

 Although satisfactory in certain cases, these methods do not make it possible to obtain a homogeneous distribution of said treating product around said seeds and / or seeds.

 According to batch processes, kneaders are used, with a rotating cylindrical tank and / or a rotating bottom, into which the treating product is introduced and said seeds and / or seeds are brewed.

 However, such methods also do not make it possible to obtain a homogeneous coating.

 In addition, the movement imposed on the products treated in the various processes and / or devices mentioned above too often lead to the alteration of the seeds and / or treated seeds. Indeed, in the case of the use of an endless screw, said seeds and / or seeds are compressed against the walls of the screw while, in known mixers, the too high speed of rotation of the latter causes numerous shocks destructive.

 The object of the present invention is to provide a mixer for pulverulent products which overcomes the aforementioned drawbacks and makes it possible to obtain a homogeneous mixing of said products.

 Another object of the present invention is to provide a mixer for pulverulent products provided with means for spraying a treating product which allows a regular distribution of said treating product on said pulverulent products.

 Another object of the present invention is to provide a mixer for pulverulent products which does not alter the mixed products.

 Another object of the present invention is to provide a mixer for pulverulent products as well as its application to the coating of seeds and / or seeds which make it possible to reduce cycle times.

 Other objects and advantages of the present invention will appear during the description which follows which is given only for information and which is not intended to limit it.

The present invention relates to a mixer for pulverulent products, in particular intended for the treatment of seeds and / or seeds, comprising a rotating tank, having at least a longitudinal axis, a bottom and an upper opening, as well as means for driving said tank in rotation around its longitudinal axis, characterized in that:
- said tank is of polygonal section,
- Said mixer also comprises means for oscillating said tank around a second axis, oriented in a direction different from said longitudinal axis, in order to promote homogeneity of stirring.

The invention also relates to a method using the mixer for pulverulent products, described above, in particular intended for the treatment of seeds and / or seeds, in which:
an angular transport surface of said pulverulent products is provided in a continuous movement of rotation about itself around a longitudinal axis,
- Oscillating said longitudinal axis at least temporarily simultaneously with said rotational movement of said transport surface about a second axis, oriented in a direction different from said longitudinal axis.

 The invention further relates to an application of said mixer, further comprising means for spraying a treating product inside the tank, for coating seeds and / or seeds.

The invention will be better understood on reading the following description accompanied by the attached drawings which form an integral part thereof and among which:
FIG. 1 describes, in side view, an exemplary embodiment of the mixer according to the invention,
FIG. 2 is a sectional view along the line II-II shown in FIG. 1,
FIG. 3 is a top view illustrating the lower half of an exemplary embodiment of the interior of the mixer tank according to the invention,
FIG. 4 is a top view illustrating the upper half of an embodiment of the interior of the mixer tank according to the invention,
- Figure 5 is a developed view of the tank shown in Figures 3 and 4 above.

FIG. 6 is a schematic perspective view of the lower half of the tank shown in FIG. 3,
FIG. 7 is a sectional view, along the line VII-VII shown in FIG. 3, of the tank illustrated in FIGS. 3 and 4 above,
- Figure 8 illustrates the section, in the direction marked VII-VII in Figure 3 above, of a second embodiment of the interior of the tank of the mixer according to the invention.

 The present invention relates to a mixer for pulverulent products, in particular intended for the treatment of seeds and / or seeds.

 Although more particularly developed for the coating of said seeds and / or seeds, it can be used, in general, in all sectors of economic activity in which it is desired to brew powdery products.

 As shown in Figures 1 and 2, the mixer according to the invention comprises a rotating tank 1, having a longitudinal axis 2, a bottom 3 and lateral flanks 4 defining an upper opening 5. According to the invention, the section of said tank 1 along a plane orthogonal to its longitudinal axis 2 is polygonal, for example along a substantially regular polygon.

 Said mixer also comprises, on the one hand, means 6 for driving said tank 1 in rotation about its longitudinal axis 2 and means 7 for oscillating said tank 1 around a second axis 8, oriented in a different direction.

 The structure of the tank 1 combined with its drive in two distinct movements thus makes it possible to promote the homogeneity of the stirring of the pulverulent products introduced into said mixer.

 The tank 1 has, for example, a support frame 9 comprising, in particular, a stirrup 10 at the level of which said tank 1 is subject to free rotation about its longitudinal axis 2, in particular by means of a shaft II provided in the bottom of said tank 1 and cooperating with the bottom of said stirrup 10.

 The frame 9 also comprises, for example, a support shaft 12 of said stirrup 10, provided for free rotation on each side of the tank 1 at its lateral sides 4, said axis 8 of oscillation of said tank 1 being constituted , in particular, of said support shaft 12.

 The means 6 for driving said tank 1 in rotation are subject, for example, to said caliper 10 and consist, in particular, of a motor 13, actuating a geared motor 14 at the outlet of which is a first toothed wheel 15 cooperating, by through a chain 16, with a second toothed wheel 17, provided on the shaft 11 of the tank 1.

 The means 7 for oscillating said tank 1 are subject, for example, to the frame 9 in the vicinity of the shaft 12 for supporting the stirrup 10.

They consist, in particular, of a motor 18, associated with a geared motor 19 driving, via a first toothed wheel 20, a second toothed wheel 21, subject to said support shaft 12 of the caliper 10 .

 As developed below, said means 7 for oscillating the tank 1 are able, for example, to operate, at least temporarily simultaneously with the rotational driving of said tank 1 around its longitudinal axis 2.

 Furthermore, according to the embodiment shown, said longitudinal axis 2 and the oscillation axis 8 of the tank 1 are located in the same plane and / or are perpendicular to each other, the oscillation axis 8 being provided, substantially, in the lower part of said tank 1.

 The latter is optionally provided, under its bottom 3, with reinforcements 35.

 If we now refer to Figures 3 to 8, we see that the mixer according to the invention further comprises, for example, deflectors 22, constituting, in particular, slope breaks and level breaks at level inside said tank 1, according to the direction of rotation of the latter.

 The presence of said deflectors 22 thus implies a reduction in the kneading volume inside said tank 1, the latter having a substantially prismatic external appearance while the shape of its internal cavity approximates, for its part, to a polyhedron, substantially regular.

 Thanks to said deflector 22, the mixing in the vein of powdered products is further improved, these causing, in a way, an additional movement of threshing.

 In addition, according to the illustrated embodiment, still in order to promote the homogeneity of stirring of the pulverulent products, said deflectors 22 are provided, optionally, opposite, on the one hand on the bottom of the tank 3 and on the other side of the tank opening side 5, so as to allow, in addition, a movement back and forth of at least a portion of said pulverulent products along the longitudinal axis 2 of said tank 1.

 As more specifically illustrated, in particular, in FIGS. 3 and 4, said deflectors 22 are provided, according to the embodiment shown, at least the number of n / 2 on the bottom of the tank 3 and at least the number of n / 2 on the opening side of tank 5, n provided as a pair, being the number of lateral sides 4 of the polygon forming the section of tank 1.

 In addition, said deflectors 22 are distributed, for example, on the tank bottom side 3 eVou tank opening 5, regularly along the lateral flanks 4 of said tank 1. They thus define, in particular, n / 2 angular sectors, for example of same surface.

 If we now refer to FIGS. 5 to 7, FIG. 5 illustrating in dotted lines the trace of the deflectors 22 on each of the lateral flanks 4 of the tank 1, it can be seen that the deflectors on the bottom of the tank 3, called bottom deflectors 22b , consist, for example, of two walls 23, 24, provided in the vicinity of two contiguous lateral flanks 4, one of the walls 23, called the first wall, ensuring at least a break in slope and the other 24, called the second wall , ensuring a level break, in the direction of rotation of said tank 1, the latter, illustrated by the arrow marked 25, being defined, according to the embodiment represented by the clockwise direction when looking at tank 1 from opening 5 to bottom 3.

 Furthermore, said deflectors on the tank opening side 5, called high deflectors 22h, consist for example of a wall 26, also provided in the vicinity of two contiguous lateral flanks 4.

 More specifically, according to the embodiment illustrated in particular in Figure 6, said two walls 23, 24 of the bottom deflectors 22b constitute, in particular, a dihedral in which the first wall 23 is in the form of a parallelogram, adjacent to two lateral flanks 4 contiguous of the tank 1, having a common edge, called edge 27b relating to the bottom deflector 22b, one of the vertices 23a of said parallelogram being on said edge 27b relating to the bottom deflector 22b. In addition, said first wall 23 is orthogonal to one of the lateral flanks, called straight flanks 4d, while it is inclined between the other flank, said deflected flank 4f and the tank bottom 3.

 The other vertex 23b on the side of said parallelogram located on the right flank 4d is located, for example, on the lateral edge adjacent to said edge 27b relative to the bottom deflector 22b, at its summit on the bottom of the tank 3.

 Furthermore, the second wall 24 is, in particular, in the form of a triangle, adjacent to the tank bottom 3 and to the deflected flank 4f, said second wall 24 being orthogonal to said first wall 23, along a sharp or softened edge .

 Said second wall 24 is located, at the level of said deflected flank 4f, for example, at a slight distance from the lateral edge adjacent to the edge 27b relative to the bottom deflector 22b, so as to form a groove with the neighboring bottom deflector 22b .

 As regards the wall 26 of the top deflectors 22 h, this is, for example, in the form of a triangle whose apex 26 a is on the common edge between two contiguous lateral flanks 4, called edge 27 h relative at the top deflector 22h, and whose base, oriented towards the tank opening side 5, has ends 26b, 26C located in the vicinity and / or on the two lateral edges 27 surrounding said edge 27h relating to the top deflector 22h.

 The apex 26a of said wall 26 is, for example, in the middle of tank 1, substantially at the same level as the edge of the parallelogram forming said first wall 23 provided on said deflected sides 4f.

Furthermore, one of the vertices 26b is located on one of the vertices of said tank 1, on the tank opening side 5, on the lateral edge adjacent to said edge 27h relative to the high deflector 22h, The other summit 26C of the base of said triangle being provided, at a distance from the top of the other lateral edge surrounding said edge 27h relative to the top deflector 22h, on the edge of the top of the tank 1 joining its last two lateral edges
According to the illustrated embodiment, the bottom deflectors 22b and top 22h are offset with respect to each other, one of said lateral flanks 4 relating to a top deflector 22h being a straight flank 4d of a first bottom deflector 22h and l another side flank relative to the same top deflector 22h being a deflected flank 4f of a second separate bottom deflector 22f.

 As a remark, it can be noted that the tank 1 can also rotate in the opposite direction of rotation to that illustrated. Likewise, it is also conceivable to provide low deflectors 22b forming a dihedral with a double slope, symmetrical with respect to the plane defined by the edge common to said deflector 22b and the center of the tank bottom 3, the direction of rotation then being indifferent. .

 Furthermore, the mixer 1 has, optionally, on the tank opening side 5, inclined flanks 28, adjacent to said lateral flanks 4, forming a truncated pyramid whose base is therefore a polygon and whose fictitious apex is on the longitudinal axis 2 of said tank 1, outside of the latter. They make it possible, in particular, to avoid premature ejection of the pulverulent products during the movements of said tank 1.

 Referring now to FIG. 8, it can be seen that, according to the illustrated embodiment, the upper edge 29 of the wall 26 forming the top deflectors 22h is subject, at each of its vertices, to the edge of said inclined sides 28 defining the opening of the tank 1.

 However, as mentioned above, the deflectors 22 make it possible, if necessary, to give the pulverulent product a movement back and forth. Indeed, in combination with the oscillations of the tank 1 around the second axis 8, the first wall 23 of the bottom deflectors 22b makes it possible to guide at least part of said pulverulent products, as illustrated by the arrow marked 29, towards the middle of the tank and the wall 26 of the top deflectors 22h enables the said pulverulent products to be folded down, as illustrated by the arrow marked 30, in the direction of the tank bottom 3.

 According to the illustrated embodiment, said tank 1 is of hexagonal section, in a substantially regular hexagon.

 The mixer also comprises, optionally, means for spraying, not shown, a product treating inside the tank 1.

 It could be, for example, a spray cane, introduced horizontally into said tank 1, the ejection end of said cane being, substantially, in the middle of the tank during spraying.

 Said mixer can also further comprise, in particular, means, not shown, for circulating a flow of hot air inside the tank 1. They consist, for example, of a fan, associated with a flexible blowing sleeve, capable of being introduced into said tank 1 through its opening 5.

 Such a flow of hot air will favor, in particular, the fixing of the spraying treatment products on the kneaded powdery products. In fact, said treating products most often consist of active agents dissolved in a solvent and said air flow makes it possible to accelerate the evaporation of the solvents while also making it possible to avoid sticking of said materials. powdery between them.

 The present invention also relates to a method using the mixer, described above, for powdery products, in particular intended for the treatment of seeds and / or seeds.

 Referring again to Figures 1 and 2, we see that, according to the method according to the invention, there is provided an angular transport surface 1 of said pulverulent products in continuous rotation movement on itself about a longitudinal axis 2 and said longitudinal axis 2 is made to oscillate, as illustrated by the arrow marked 31, at least temporarily simultaneously with said rotational movement of said transport surface 1, around a second axis 8, oriented in a direction different from said longitudinal axis 2 .

 In addition, the trajectory of said pulverulent products is optionally deflected locally along said transport surface 1 by providing for slope and / or level breaks.

 According to an exemplary implementation, said angular surface 1 is driven at a slow speed of rotation around the longitudinal axis 2, said longitudinal axis 2 performing, continuously, simultaneously, at least one oscillation, of maximum amplitude of 90 ", around said second axis 8, during a stirring operation.

 The speed of rotation around axis 2 may thus vary, for example, between 0 and 40 revolutions / minute and will thus promote, in particular, the reduction of too violent shocks between the particles forming said pulverulent product. As for the oscillations around the axis 8, they are carried out, in particular, continuously between the vertical, the opening 5 of the tank 1 being oriented upwards, and the horizontal, and, more precisely, for example , between an angle of 60 to 85 relative to the horizontal and the horizontal.

The different phases of a kneading are, in particular, the following. The powdery products are first introduced into the tank 1,
The opening 5 of the latter being oriented upwards, said pulverulent products are then kneaded in the tank 1 by combining the various stirring movements described above then, after stopping said movements, said tank 1 is emptied by tilting this last down, as shown by the arrow marked 32.

 It is also conceivable to orient said tank horizontally, as illustrated by the arrow marked 33, in the washing position.

 The present invention also relates to the application of the mixer described above to the coating of seeds and / or seeds. According to this particular use, said seeds and / or seeds are brewed according to the different stages mentioned above, the spraying of the coating treatment product being carried out, after introduction of said seeds and / or seeds into the tank 1, the latter having been then tilted horizontally.

 It should also be noted that, according to this example of application, when said tank 1 is in the stirring movement, a flow of hot air is circulated, if necessary, so as, as previously mentioned, to favor the fixing of the treating product. on said seeds and / or seeds.

 However, care must be taken not to exceed a certain temperature so as not to risk damaging their germ by excessive heat.

 For example, the treating products used are insecticides, fungicides or the like.

 Different coating examples are given below for a tank 1 having lateral flanks 4 with a height of 1 m, a hexagonal bottom 3 inscribed in a circle of 1.60 in diameter and inclined flanks 28 to 45 of a height of 400 mm.

 According to this embodiment, the pulverulent products are treated in portions of 250 kg, the tank I being half filled. A brewing operation is carried out, for example, in one minute, thus making it possible in particular to achieve a throughput of 15 tonnes / hour.

 With rapeseed, the sprayed treatment products are, for example, based on ophthanol, the quantity used being, substantially, from 12 to 14 liters / quintal of seeds and / or seeds. Under the same conditions, for other cereals, the dose of sprayed treatment product may vary, in particular, from 2 to 14 liters.

 Naturally, other implementations, within the reach of those skilled in the art, could have been envisaged without departing from the scope of the present invention.

Claims (12)

 1. Mixer for powdery products, in particular intended for the treatment of seeds and / or seeds, comprising a rotating tank (1), having at least one longitudinal axis (2), a bottom (3) and an upper opening (5), thus that means (6) for driving said tank (1) in rotation about its longitudinal axis (2), characterized in that:  - said tank (1) is of polygonal section,  - Said mixer also comprises means (7) for oscillating said tank (1) around a second axis (8), oriented in a direction different from said longitudinal axis, in order to promote homogeneity of stirring.  2. Mixer according to claim 1, further comprising deflectors (22), constituting slope breaks and / or level breaks inside said tank (1), according to the direction of rotation of this  s last.  3. Mixer according to claim 2, in which said deflectors (22) are provided, opposite, on the one hand on the tank bottom side (3) and on the other hand on the tank opening side (5), so as to allow, in addition, a movement back and forth of at least a portion of said pulverulent products, along the longitudinal axis (2) of said tank (1).  4. Mixer according to claim 2, in which n being the number of lateral sides (4) of the polygon, said deflectors (22) are provided:  - at least the number of n / 2 on the tank bottom side (3),  - at least the number of n / 2 on the tank opening side (5), and are distributed regularly along the lateral sides (4) of said tank (1),  - Said baffle side deflectors (3), called bottom deflectors (22b), being made up of two walls (23, 24), provided in the vicinity of two contiguous lateral sides (4), one of the walls (23) said first wall , ensuring, at least one break in slope, and the other (24), said second wall, ensuring a break in level, in the direction of rotation of said tank (1),  - Said deflectors on the tank opening side (5), called the top deflector (22h), being made up of a wall (26) provided in the vicinity of two contiguous lateral flanks (4).  5. Mixer according to claim 4, in which:  - said two walls (23, 24) of the bottom deflectors (22b) constitute a dihedral:  - The first wall (23) in the form of a parallelogram, adjacent to two lateral bottoms (4) contiguous with the tank (1), having a common edge, called edge (27b) relating to the bottom deflector (22b) , one of the vertices (23a) of said parallelogram located on said edge (27b) relating to the bottom deflector (22b), said first wall (23) being orthogonal to one of said lateral flanks, called straight flank (4d), and inclined between the other side, called deflected side (4f), and the bottom of the tank (3),  the second wall (24) being in the form of a triangle, adjacent to the tank bottom (3) and to the deflected side (4f), said second wall (24) being orthogonal to said first wall (23),  - Said wall (26) of the top deflectors (22h) is in the form of a triangle whose apex (26a) is on the common edge between two contiguous lateral flanks (4), called edges (27h) relating to the high deflector (22h), and whose base, oriented towards the tank opening side (5), has ends (26b, 26C) located in the vicinity and / or on the two lateral edges (27) surrounding said edge (27h) relating to the high deflector (22h), one of said lateral flanks being a straight flank (4d) of a first low deflector (22b) and the other being a deflected flank (4f) of a separate second low deflector (22b).  6. The mixer of claim 1, wherein said polygon is a hexagon.  7. Mixer according to claim 1, further comprising means for spraying a treating product inside the tank (1).  8. Mixer according to claim 1, further comprising means for circulating a flow of hot air inside the tank (1).  9. Method using the mixer, for powdery products, according to claim 1, in particular intended for the treatment of seeds and / or seeds, in which:  an angular transport surface (1) of said pulverulent products is provided in a continuous movement of rotation about itself around a longitudinal axis (2),  - Oscillating said longitudinal axis (2) at least temporarily simultaneously with said rotational movement of said transport surface (1), around a second axis (8), oriented in a direction different from said longitudinal axis (2).  10. The method of claim 9, wherein locally deflects the path of said pulverulent products along said transport surface (1) by providing breaks in slope and / or level (22).  11. The method as claimed in claim 9, in which said angular surface (1) is driven at a slow speed of rotation, said longitudinal axis (2) continuously carrying out at least one oscillation, with a maximum amplitude of 90 ", during a brewing operation.  12. Application of the mixer according to CLAIM 7 to the coating of seeds and / or seeds.