SILO FOR BULK GRAIN STORAGE

Abstract

A silo for the bulk storage of grain, in which grain is discharged through a large number of non-clogging openings 116, closed by individually actuated rotary flaps 119. According to the invention, a cam 119, controlled by sensors 167 and 168 that regulate the grain level in the infeed conveyor, controls the discharge rate by opening or closing the rotary flaps.

Description

"Silo for bulk grain storage" This application relates to a certificate of addition to the main patent No. 86 00683 filed on January 20, 1986, which relates to a silo for the bulk storage of cereals or other granular or powdery products. This silo includes a storage building whose base consists of an inclined slab on which rests a metal plate equipped with vibrators, designed to ensure the emptying of the silo, the evacuation of the grains being done by a recovery conveyor. The conveyors currently in use all have a limited number of discharge openings per cell, generally one automated, electro-mechanical or electro-pneumatic opening, and several manual drawers. Such an opening system is not suitable for the vibrating floor, which requires multiple closely spaced openings, allowing good evacuation of the grains along the entire length of the recovery conveyor. The purpose of this addition is to improve the transfer of grains in the retrieval conveyor, and to simplify the assembly of the vibrating floor. The silo considered in this addition is characterized in that the conveyor box lid is composed of sections each having one or more sets of two openings, each set being closed by a pivoting flap mounted under the lid. According to a particular feature of the invention, a cam moved in translation along the cover by a cable, pivots the flaps when opening or closing, depending on the direction of its movement. Advantageously, the movement of the cam, at opening or closing, is controlled by the level of the product in the box of the retrieval conveyor. In a preferred embodiment of the invention, but which is not exclusive of the latter, two cams circulate in opposite directions from the center of the silo, each actuating half of the pivoting flaps. According to another feature of the invention, the ventilation ducts and sealing membranes are held in place by special profiles, bolted to the foundation slab. Other improvements to the silo brought about by this addition will become apparent through the following description of an example implementation given by way of illustration and not limitation, and in which: - Figure 1 is a partial top view inside the storage building. - Figure 2 is a partial cross-sectional view, along line III-III of Figure 1. - Figure 3 is a larger-scale partial top view of the reclaimed conveyor box. - Figure 4 is a partial cross-sectional view of the conveyor cover, along line II of Figure 3. - Figure 5 is a partial cross-sectional view of the conveyor cover, along line II-II of Figure 3. - Figure 6 is a larger scale detail view of Figure 2, in the vicinity of the central channel. - Figure 7 is a partial longitudinal section view, along line IV-IV of Figure 1. - Figures 8, 9 and 10 are larger scale detail views of figure 7. In the example of implementation shown in these figures, the silo under consideration includes a storage building 1, delimited by walls 2 and by two inclined slabs 18 on either side of a drainage channel 10. A metal plate 19 rests on slab 18 Consisting of 26 juxtaposed sheets, at least some of which carry a vibrator 32. With reference to Figure 2, the drainage channel 10 consisting of a bottom slab 53 and two side walls 51 contains a metal box 43, housing a recovery conveyor not shown. With reference to figures 3 and 4, the metal box 43 has side walls 44 and a hood 47. The hood 47 is composed of covers 115, which may include at least one set of two openings 116, preferably circular, and preferably aligned on the longitudinal axis of the hood 47. In the middle of two associated openings 116, a bore 117 provided in the cover 115 receives a pivot 118, integral with a flap 119 disposed under the cover 115. The pivot 118 is held in position by a nut 12U and a lock nut 121, which compress a return spring 122 between a washer 123 and an anti-friction washer 124 made of Teflon or equivalent, in contact with the upper face of the cover 115. An arm 125, fixed to the pivot 118 under the cowling 115, comprises two vertical wings 126 and 127. An open airfoil 128 is attached to the upper part of each of the walls 44 inside the housing 43, the opening of the airfoil preferably facing the bottom of the housing. A shuttle 129 of oblong shape travels within the airfoil 128, the ends 130 of which are tapered to facilitate the shuttle's movement within the airfoil 128. The diane portion of the shuttle 129 is fixed to a cam finger 133, which slides within the opening of the airfoil 128. The relative position of the flap 119, the arm 125, and the cam finger 133 is such that, with the flap closing the two openings 116, the cam finger 133 abuts against the wing 126 of the arm 125. In a particular embodiment of the present invention, but which in itself is not exclusive of the latter, each end 130 of the shuttle 129 has an axial eye stud 131, connected to a cable 132. With reference to figures 3 and 5, the translation of the shuttle 129 is obtained by the rotation of a capstan 134 on which the cable 132 is wound. The shaft 134a of the capstan 134, which can slide in an oblong hole 134b made in the hood 47, is connected to a geared motor 135, mounted on the hood 47 in the immediate vicinity of the wall 2 of the silo. The base 138 of the geared motor 135 can slide between two slides 139 fixed to the upper part of the cover 47 parallel to the longitudinal string of the casing 43. A screw 140 fixed in translation to the base 138, and screwing into a stop 141 fixed on the cover 47, ensures the translational movement of the base 138, in the axis of the casing 43. The cable 132 is engaged at the four corners of the cover 47 in grooved pulleys 136, the flanges 137 of which are rigidly fixed to the walls 44. Referring to Figure 6, a vibrating rod 142, arranged vertically along the axis of an opening 116, is rigidly fixed to a support 143, bolted to the base of a vibrating plate 26. End plates 144, screwed or nailed to the wall 51 of the discharge channel and screwed to the conveyor cover 47, are preferably part of hoppers (not shown) designed to make the cover 47 self-cleaning. The lower part of the plates 26 rests on a flexible seal 145, arranged parallel to the discharge channel. A housing 166 is fixed to the side wall 44 of the conveyor box 43, opposite an opening 165 made in the wall 44. Two level probes, 167 and 168, are mounted on the housing 166 parallel to the longitudinal axis of the box 43, and electrically connected to the control panel, not shown, of the geared motor 135. The probes 167 and 168 can be capacitive, finned, ultrasonic, infrared or other, their detection element being located inside the housing 43. With reference to figure 7, a wire 146, stretched across the top of a ventilation duct 41 along its entire length, is connected to the middle of a wire 147, the ends of which are fixed to the edges of the sheets 26 adjoining the duct 41. Referring to Figure 8, the seal between the 9-wall 41 and the vibrating sheet 26 is ensured by a strip 148, made of spring steel or equivalent material. One lateral edge of the strip 148 is engaged in a groove of a horizontally arranged rigid "H" profile 149, the other groove of the profile 149 fitting onto the edge of the sheet 26, to which it is fixed by riveting, bolting, or keying 150. The other lateral edge of the strip 148 is engaged in a recess 151 of the horizontal flange 152 of a rigid profile 103, fixed to the slab 18 by anchor bolts 86. The inclined flange 153 of the profile 103 has a groove 154, into which the sheet 102 of the ventilation duct 41 is engaged. In another sealing system, represented in figure 9, the profile 103 has a groove 155 in which a lateral bead 156 of a flexible membrane 106 is housed. The bead 156 has a groove 157 into which the sheet metal 102 of the ventilation duct 41 engages. The membrane 106 has at its other lateral end, a bead 158, preferably having a trapezoidal cross-section. A profile 169, preferably formed by elastic interlocking of two rigid elements 159 and 160, has a gouge 161 in which the bead 158 of the membrane 106 is housed, and a groove 162 that can fit into the edge of the sheet 26. The profile elements 159 and 160 are joined by self-threading screws 163, and fixed to the sheet 2b by riveting, bolting or keying 164. Figure 10 represents another method of connecting the membrane 106 with the sheet 26. In this example, the flexible membrane 106 and its ridges 156 and 158 are obtained by bi-extrusion, the ridge 158, of higher rigidity, including the groove 162 for fixing to the sheet 26. The operation of the silo emptying system described in the example above is as follows. When the geared motor starts, the "optimal level" probe 168, detecting no product, confirms that the motor has started. The rotating cable 132 causes the shuttle 129 to move, which, through the action of the cam finger 133 on the wing 126 of the arm 125, causes the flap 119 to rotate and the orifices 116 to open. When the level of the product entering the conveyor reaches the probe 168, it causes the motor-reducer 135 to stop, and therefore the shuttle 129 to stop. In the event that the level of the product in the conveyor increases until it reaches the "maximum level" probe 167, this triggers the starting of the geared motor in the opposite direction, causing the shuttle 129 to return to its starting point, and the openings to the passage of the shuttle to close, thus reducing the flow in the conveyor box. As soon as the product level in the container 43 drops sufficiently to release the probe 167, the probe stops the geared motor, thus stopping the closing movement of the orifices 116. If the product level continues to fall below the level of the probe 168, the probe activates the geared motor in the direction of opening the orifices 116, in order to increase the drainage flow rate. This results in a fully automated opening system, ensuring optimal discharge flow, while avoiding overloading of the conveyor. The shutters 119 are kept in contact with the underside of the lid 115 by the compressive force of the return spring 122, adjustable by the device tightening 120 and 121. The tension of cable 132 is adjusted by translating the base 138 of the geared motor 135, by simple action on screw 140. A single shuttle can be sufficient to open all the openings of a conveyor, by traveling from one wall of the silo to the other. However, it may be imperative to maintain the symmetry of the silo loading at all times, for structural reasons. In this case, two shuttles 129 chemi nant on each side of the lid 47 and in two directions Opposite each other, starting from the center of the silo, they allow for preservation an equal number of orifices 116 in the open position, on the one hand and on the other side of the center of the silo. It is agreed that the movement of the two shuttles should be slightly offset, so that avoid their simultaneous action on two aspects 119. It goes without saying that a chain could replace cable 132 without departing from the present invention. In this In this case, the return pulleys 136 and the capstan 134 would be replace them with toothed gears. Similarly, a motorized shuttle, moving on a rack and pinion, or by any Another means would fall without restriction within the scope of the present invention. Furthermore, the opening system could be housed in a closed casing, the profiles 128 then being oriented with the opening towards the longitudinal axis of the hood 47, and held between the covers 115 and a closing plate. lower. The latter would have screw openings & screws of the orifices 116, connected to these by sections of tube of the same internal diameter, the shutters 119 s,e then piercing under the lower face of the box thus formed. The rods 142, subjected to the vibrations of the sheets 26, prevent the clogging of the associated openings. Wire 146, set into vibration by means of wire 147 connected to vibrating plates 26, allows the evacuation of grains which would otherwise tend to remain at the top of the ventilation duct 41. Finally, the various profiles and membranes described ensure the rapid assembly and efficiency of the sealing system. This results in a fully automatic drainage system, allowing optimal drainage flow without overload, clogging-free, and fully self-cleaning.

Claims

DEMANDS 1 - Bulk grain storage silo according to claim 1 of the main patent, characterized in that the transfer of grain from the vibrating plates (26) into the retrieval conveyor is carried out by a large number of openings (116) in a hood (47), closed by individually operated rotating flaps (119). 2 - Storage silo according to claim 1, characterized in that a rotating flap (119) closes two contiguous openings (116), symmetrical with respect to the center of rotation of the flap. 3 - Storage silo according to claim 2, characterized in that a shuttle (129) actuates the opening and closing of the rotating flaps (119) by means of a cam finger (133). 4 - Storage silo according to claims 1 to 3, characterized in that two shuttles (129) moving in opposite directions each actuate half of the rotating flaps (119) a- from the center of the silo. 5 - Storage silo according to claims 1 to 4, characterized in that the number of open orifices (116) is controlled by the loading level of the recovery conveyor, by means of capacitive, paddle, ultrasonic, infrared or other level probes (167) and (168). 6 - Storage silo according to claim 1, characterized in that rods (142) attached to the lower edge of the sheets (26) vibrate in relation to the openings (116). 7 - Storage silo according to claim 1, characterized in that a wire (146) stretched at the top of a ventilation duct (41) is set into vibration by connection with a wire (147) whose ends are connected to the vibrating plates (26). 8 - Storage silo according to claim 1, characterized in that a rigid profile (103) has a groove (154) into which the edge of a sheet (102) of a ventilation duct (41) fits. 9 - Storage silo according to claim 8, characterized in that the base of the profile (103) has a recess (151) in which the wing of a sealing strip (148) is housed, the other wing of the strip engaging in a groove of a rigid horizontal H-profile (149), the other groove of which fits and is fixed on the edge of the sheet (26). 10 - Storage silo according to claim 1, characterized in that a rigid profile-(103) has a groove (155) in which the lateral bead (156) of a flexible membrane (106) is housed, which bead has a groove (157) in which the edge of a sheet (102) of a ventilation duct (41) fits. 11 - Storage silo according to claim 10, characterized in that the other end of the membrane (106) is formed into a bead (158) fitting into the groove (161) of a rigid profile (169), comprising a groove (162) for fitting and fixing on the edge of the sheet (26). 12 - Storage silo according to claims 10 and 11, characterized in that the profile (169) is composed of two profiles (159) and (160), assembled by elastic interlocking. 13 - Storage silo according to claim 10, characterized in that the flexible membrane (106) and its ridges (156) and (158) are obtained by bi-extrusion, the ridge (158) having a higher rigidity, and a groove (162) for fitting and fixing on the edge of the sheet (26).