JP3677861B2 - Granule sorting method and granule sorting apparatus using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is a method of selecting a granule capable of selecting and removing contaminants that have been difficult to select conventionally, such as glass particles mixed in a group of rice grains, such as a selection of particles having a very small specific gravity difference. The present invention relates to a particle sorting apparatus.
[0002]
[Prior art]
Conventionally, various methods have been used as means for selectively removing foreign matters mixed in grains such as rice grains. For example, in the case of rice grains, i) grain size selection based on netting, ii) specific gravity selection based on specific gravity difference, iii) color selection based on color difference, and iv) metal selection based on electromagnetic wave fluctuation difference. Are known.
[0003]
[Problems to be solved by the invention]
However, especially when focusing on the removal of contaminants in rice grains, it cannot be removed by the above conventional sorting method. For example). Hereinafter, in order to promote understanding of the present invention, the removal of glass pieces in rice grains will be described as an example.
The main cause of glass fragments in rice grains is traffic accidents on rural roads. This car accident breaks the windshield of the car and breaks it into the rice when it is harvested. Unlike conventional glass, this glass piece has been considered to have a specific gravity equal to or smaller than that of rice grains, and it has been determined that it cannot be removed by any conventional sorting method. However, according to the investigation by the present inventor, most of the mixed glass pieces have a specific gravity of about 2.3. Therefore, the present inventor paid attention to why this glass piece cannot be removed by the conventional specific gravity sorting method even though the specific gravity is larger than that of rice grains.
As a result of detailed examination of this cause, most of the glass pieces that could not be removed conventionally have a volume smaller than that of rice grains, and there are many sharp irregularities on the surface, and the specific gravity is larger than that of rice grains, but the difference is large. Because of its small size, the value of weight / surface area (value divided by weight divided by surface area) is very close to or less than that of rice grains, and one rice grain has a specific gravity of about 1.6, from large grains to small grains, The smallest particles are about 5 mm long, about 2.4 mm wide, and about 1.7 mm thick. They have a rugby ball-like shape, and the surface is extremely smooth. I found out that the difference was the main cause.
[0004]
Hereinafter, in each of the above-described sorting and removing methods, removal of glass pieces mixed in rice grains is taken as an example, and the difficulty of removal will be described.
i) Grain size selection
The grain size selection of rice grains is usually performed by using a “longitudinal sieve” in which wires are stretched at a predetermined interval in one direction, and foreign matters mixed in the rice grains are dropped from between the wires. And the space | interval of this wire is set as 1.7 mm so that a rice grain may not fall as an example. However, as described above, since the glass piece has many sharp irregularities on the surface, even if it is about 1.5 mm square on the surface, it will be caught on the wire and will not fall easily. It will remain.
[0005]
ii) Specific gravity sorting
Conventional specific gravity sorting is performed by inclining a perforated plate with a long hole opened in the entire surface, with the opening direction being oblique to the plate surface, and from below to above the long hole of the perforated plate. The rice is allowed to pass through, and only the rice grains having a specific gravity smaller than that of the foreign substances are floated to separate and sort the rice grains and the foreign substances.
Such specific gravity sorting is based on the assumption that foreign matter does not float due to wind because it is intended for foreign matter whose specific gravity is significantly greater than that of rice grains, particularly stone (specific gravity is about 3.0). Therefore, a glass piece having a smaller specific gravity difference than rice grains easily floats and cannot be removed.
[0006]
Further explanation of this point is as follows. As the size (dimension) of an object decreases, the surface area per unit volume increases. This is because the volume of the object is proportional to the cube of the size, whereas the surface area is proportional to the square of the size. Therefore, the smaller the volume, the smaller the volume / surface area value (the value obtained by volume / surface area). Since the buoyancy received by the object is constant per unit surface area if the medium is the same, in general, the smaller the particle body, the easier it is to float.
On the other hand, whether or not an object floats in the medium depends on whether or not the buoyancy received is greater than the weight of the object. That is, the above-mentioned value of the weight / surface area value represents the ease of floating in the same medium regardless of the specific gravity.
Here, considering this in the case of the rice grains and glass pieces, “firstly, the glass pieces to be removed have a smaller volume than the rice grains”, “secondly, the surface of the rice grains is smooth. On the other hand, since the surface of the glass piece has many sharp irregularities, the value of the volume / surface area of the glass piece becomes smaller than that of rice grains. Therefore, the difference in specific gravity between the two is offset by the difference in properties, and as a result, the weight / surface area value of the glass piece is very close to or less than that of rice grains, and in some cases, it tends to float more than rice grains. That can happen.
[0007]
iii) Color selection
In the color sorting, foreign matter is determined and removed based on the color of the surface. Needless to say, the glass piece has a color similar to that of rice grains, and therefore cannot be sorted and removed.
[0008]
iv) Metal sorting
Glass pieces are insulators, unlike metal foreign objects, and naturally cannot be removed by metal sorting.
[0009]
As described above, with the conventional sorting and removing method, it has been impossible to surely remove the glass pieces mixed in the rice grains.
[0010]
[Means for Solving the Problems]
Under such circumstances, the present inventor conducted intensive research and led to the concept of “volume selection” in addition to the above four selection methods, resulting in a difference in specific gravity represented by glass pieces in rice grains. Have devised a grain sorting method and a grain sorting apparatus using the same.
In such a method of selecting particles in the present invention, a number of elongated holes whose opening direction is oblique to the plate surface are opened, In the same direction as the opening direction of the long hole, 7 ° to 14 ° with respect to the horizontal direction direction Perforated plate provided in a slanted direction; 350 to 650 reciprocations per minute with an amplitude of 6 mm to 12 mm in a direction of 40 ° to 90 ° with respect to the horizontal direction in the same direction as the tilting direction of the perforated plate While moving and passing an air flow from the bottom to the top of the long hole of the perforated plate; the rice grain has a slightly higher specific gravity and smaller volume than the rice grain, and there are many sharp irregularities on the surface 1 g of the area of the porous plate from above the inclination on the porous plate ² 5.5m per hour ^Three This can be realized by flowing down at the following flow rate.
[0012]
In addition, the flow rate of air passing through the long hole of the perforated plate is set to 1 m of the perforated plate area during idling. ² 30m per minute ^Three ~ 45m ^Three It is good also as the selection method of the granule used as the range of this. This air flow rate condition is particularly suitable as a method for selecting rice grains.
[0013]
In addition, another method for selecting particles can be realized by using one of the above-described methods for selecting particles and a method for selecting particles according to the size difference between the particles and the particles. Even in this case, the flow rate of air passing through the long holes of the perforated plate is set to 1 m of the perforated plate area during idling. ² 30m per minute ^Three ~ 45m ^Three If it is within the range, it is particularly suitable as a method for selecting rice grains.
[0014]
Furthermore, for the grain sorting apparatus of the present invention, a number of long holes whose opening direction is oblique to the plate surface are opened, In the same direction as the opening direction of the long hole, with respect to the horizontal direction 7 ° -14 ° direction A perforated plate provided to be inclined to the surface; the same And a driving means for reciprocating with an amplitude of 6 mm to 12 mm in a direction of 40 ° to 90 ° with respect to the horizontal direction; a group of particles to the perforated plate, that is, a specific gravity slightly larger than the rice grain in the rice grain; The flow rate of the particle group mixed with glass pieces having a small volume and having many sharp irregularities on the surface is defined as 1 m of the perforated plate area. ² 5.5m per hour ^Three This can be realized by including a flow rate control means to be controlled below; and a blowing means for allowing an air flow to pass from the bottom to the top of the long hole of the perforated plate.
[0016]
Also, the area of the perforated plate is 1 m at the time of idling from the blower means to the long hole of the perforated plate ² 30m per minute ^Three ~ 45m ^Three May be passed through. Under this air flow rate condition, the grain sorting device is particularly suitable for rice grains.
[0017]
[Action]
Next, the operation of the present invention will be described. In the present invention, (1) the opening direction of the long hole of the perforated plate through which air passes, (2) the inclination angle of the perforated plate, (3) the direction in which the perforated plate reciprocates, and (4) the reciprocating motion of the perforated plate. By setting the amplitude and frequency, and (5) the flow rate of the particles flowing down on the perforated plate within a predetermined range, it is only possible to reliably select foreign substances with a small specific gravity difference such as glass pieces in rice grains for the first time. Can be removed. Here, as explained in the section of the means for solving the above-mentioned problems, the present invention is based on the concept of “volume selection”, but here, the point of removal of glass pieces in rice grains is taken as an example. In the following, the operation of selecting foreign substances having a small specific gravity difference from rice grains such as glass pieces by the concept of “volume selection” will be described in detail.
[0018]
The glass piece which is the subject of the present invention has a specific gravity of about 2.3, a specific gravity difference is smaller than that of about 1.6 of rice grains, and most of the volume is smaller than that of rice grains, and the surface has many sharp edges. Since unevenness exists, it cannot be reliably removed by conventional specific gravity sorting. This is because, as already described, the conventional specific gravity sorting method targets foreign substances such as stones, and presupposes that the foreign substances are submerged in the lower layer by floating only the rice grains by the wind. That is, the foreign matter such as stones to be removed has a large specific gravity relative to the rice grains, and thus has a large weight / surface area value and does not easily float by the wind.
Therefore, in the case of a glass piece, the surface area is large because the volume is smaller than that of rice grains and there are many sharp irregularities on the surface, and the specific gravity is close to that of rice grains. Since the buoyancy per unit weight by the wind is equivalent to that of rice grains, the value of the sapphire floats together with the rice grains and cannot be removed by conventional specific gravity sorting.
[0019]
About this, as described in the above-mentioned ii) specific gravity selection without needing to explain it again, the volume / surface area value generally leads to the fact that smaller particles are more likely to float if the specific gravity is equal. It can be understood from the value of the weight / surface area that the ease of floating in the same medium can be derived regardless of the specific gravity.
[0020]
On the other hand, the present invention is characterized in that foreign matter is sunk down and removed in the particle group mainly by vibration (small reciprocating motion). That is, in the present invention, for example, when the rice grain group flows down from the upper part of the perforated plate and the rice grain group flows down from the lower end of the inclination, the subsidence of the glass pieces in the rice grain group almost depends on the action of the wind. It is something that will be done. In general, when large and small grains such as soybean and sesame are mixed in a container and shaken up and down (small reciprocating motion), small sesame is separated into a lower layer and large soybean is separated into an upper layer. This is a separation by volume difference, using a mediating means called reciprocating motion to drop small grains of sesame from the gaps between large grains of soybeans, which is the principle of “volume separation” of the present invention.
[0021]
As described above, in the present invention, vibrations are imparted to the rice grains by reciprocating motion on the perforated plate installed at an inclination, and the rice grains supplied from above the perforated plate flow down from the lower end of the inclination, mainly by vibration. A piece of glass is allowed to sink to the lower layer. For this purpose, the inclination angle of the porous plate (2) is in the range of 7 ° to 14 °, the direction in which the porous plate (3) reciprocates is in the range of 40 ° to 90 ° with respect to the horizontal direction, 4) The amplitude of the reciprocating motion of the perforated plate in the range of 6 mm to 12 mm is set to 350 to 650 times per minute, and the flow rate of the particles flowing on the perforated plate of (5) is set to 1 m of the perforated plate area. ² 5.5m per hour ^Three Each of the following flow rates must be set. If even one of the conditions is not met, the glass pieces cannot sink to the lower layer of the rice grain group before the rice grain group flows down from the lower end of the slope, and the glass piece flows down from the perforated plate together with the rice grain. Here, there is a critical significance in the numerical range of (2) to (5) above.
In “volume selection”, it takes a relatively long time for the glass pieces existing in the rice grain group to sink to the lower layer, and according to the condition setting in the above range (5), the flow rate of the rice grain group is Although it is about 25% of the conventional specific gravity sorting, the glass pieces can be surely sunk before the rice grain group flows down from the end in the inclined downward direction. Therefore, in the present invention, it seems that the processing capacity is inferior to the conventional specific gravity sorting at first glance, but in the past, since it could not be removed sufficiently by one specific gravity selection, two or three specific gravity sorters were installed. However, since the present invention has only a small effect, it is sufficient to install only one unit according to the present invention, which can contribute to productivity improvement and cost reduction.
The basic principle of the present invention is based on the new concept of “volume sorting” as described above. Contrary to conventional specific gravity sorting, larger glass pieces are less likely to sink to the lower layer, making sorting difficult. It becomes. Therefore, in the present invention, a function of “specific gravity selection” is provided as a subordinate to “volume selection”. However, it is more desirable to use the sorting method of the present invention in combination with the sorting method that removes foreign matter according to the difference in size between the particles and the foreign matter.
[0022]
Further, in the present invention, the air flow passing from the bottom to the top of the long hole of the perforated plate mainly contributes to the sinking action of the glass piece and the promotion of the movement of the glass piece above the perforated plate. ing. That is, first, the air flow blows upward from the bottom of the rice grain group, thereby forming an appropriate gap between the rice grains to promote the settlement of the glass pieces in the rice grain group, and secondly, the above (3) By the synergistic action of the reciprocating force in the diagonally up and down direction of (4), the sinked glass piece acts to move upward the inclination of the perforated plate. When the glass piece moves upward in the inclined direction of the perforated plate, only the glass piece can be taken out from the inclined upper end of the perforated plate. Therefore, the presence of the air flow is useful for adding a function of specific gravity selection by wind power to volume selection by vibration (small reciprocating motion) and exerting these two synergistic effects.
In view of the above, it is desirable that the air flow blows upwardly with respect to the perforated plate. From this point, regarding the above-mentioned (1), the long hole is inclined upward and downward with respect to the plate surface of the perforated plate. And shall be.
[0023]
In addition, when the thickness of the rice grain group flowing down on the perforated plate is partially increased, the glass piece cannot sink to the lower part until the rice grain group flows down from the inclined lower end of the perforated plate at that part, and it is thicker. In the part that has become, the air flow does not blow through efficiently due to the heavy pressure, and as a result, the glass pieces that have settled in the lower part are blown up to the upper part. Therefore, it is important to make the flow bed thickness of the rice grain group uniform. For this purpose, when the rice grain group is supplied onto the perforated plate, the rice grain group may be diffused and flowed down to a wide area.
[0024]
And the air flow rate passing through the long hole of the perforated plate is set to 1 m of the area of the perforated plate during idling. ² 30m per ^Three ~ 45m ^Three If it is in the range, the glass piece does not float by the passing air, and the synergistic action of the vibration force in the diagonally up and down directions (3) and (4) described above works more efficiently. This air flow range is particularly suitable when the grains are rice grains.
Here, the size and density of the long holes to be opened in the perforated plate are not particularly limited, but this is a natural prerequisite that the long holes are opened in such a size that the rice grains do not pass through. Since the rice grain group flows down over a wide area of the perforated plate, the size of the long holes, the density of open holes, and the flow condition of the rice grain group are considered to be almost constant. This is because it is sufficient to limit only how much air flow per unit time passes with respect to the area of the perforated plate.
[0025]
By such an effect | action, the supplied rice grain group is isolate | separated from a glass piece as follows.
When the rice grains mixed with glass pieces flow down from the top of the perforated plate, the gap between the rice grains is created by the action of the subordinate air flow, while the volume selection by the reciprocating motion of the perforated plate. A glass piece having a volume smaller than that of the rice grain sinks, and a two-layer structure of a lower layer including the glass piece and an upper layer made of only the rice grain is formed. Here, since the long hole opened in the perforated plate is opened upward in the inclined direction of the perforated plate, that is, in the oblique direction with respect to the plate surface of the perforated plate, the force for conveying the rice grains upward is inclined. Although it works, since the perforated plate is installed in an inclined state, the force for conveying the rice grains upward and the gravity are balanced, and the rice grains become a layer of a certain thickness and stop almost on the spot. However, as new rice grains continue to be supplied, only the glass pieces sink due to the reciprocating motion, and only the rice grains from which the glass pieces have been removed flow downward as if they were a surface avalanche, and below the perforated plate. It is taken out from the end.
On the other hand, the glass piece contained in the rice grain group is formed in the lower layer of the rice grain group by a synergistic effect of the force due to the reciprocating motion of the perforated plate in the diagonally up and down direction and the air flow blown in the same direction as the inclined direction of the perforated plate. While sinking, it moves upward and is taken out from the upper end of the perforated plate.
[0026]
【Example】
Subsequently, as a specific example for realizing the grain sorting method of the present invention, details of the grain sorting apparatus of the present invention will be described based on the drawings.
FIG. 1 shows an overall structural diagram of a granule sorting apparatus 1 of the present invention. The example in the figure is slit-shaped and has an opening direction D _H A large number of long holes 3 that are inclined with respect to the plate surface are opened, and a large specific gravity discharge port 5 is provided at the upper end. _H The angle θ _P Is the opening direction D of the long hole 3 _H A perforated plate 7 provided to be inclined in the same direction as 7 ° to 14 °; and the perforated plate 7 is supported by a support spring plate (not shown), and in the same direction as the inclined direction of the perforated plate 7. , Horizontal direction L _H The angle θ _V Direction D in the range of 40 ° to 90 ° _V And a driving means 9 that reciprocates with an amplitude of 6 mm to 12 mm; and a flow amount of the particle group to the porous plate 7 is set to 1 m of the porous plate area. ² 5.5m per hour ^Three A flow rate control means 11 to be controlled below; a blower means 13 for allowing an air flow to pass through the long hole 3 of the perforated plate 7 from below to above; a perforation provided at an appropriate upper position above the slope of the perforated plate 7; And a diffusion supply means 15 for diffusing and flowing down the particle group on the plate 7.
[0027]
In more detail with reference to FIGS. 2 and 3 below, the perforated plate 7 is attached to the housing 17 at a predetermined angle. The drive means 9 includes an electric motor 19 and a camshaft pulley 21, both of which are connected by a transmission means 23 such as a belt. The cam shaft pulley 21 is provided with a cam 25, and a cam follower 27 of the cam 25 is connected to the housing 17. On the other hand, the air blowing means 13 has a porous plate area of 1 m during idling. ² 30m per minute ^Three ~ 45m ^Three A general fan 29 having the ability to pass the air flow is used, and is connected by the transmission means 23 such as the belt, and the motor 17 reciprocates and blows air by the single motor 19. The power of However, instead of such driving means 9, the casing 17 may be fixed and only the perforated plate 7 may be reciprocated. Also, the air blowing means 13 may be an air flow that is sent by intake air from an appropriate position above the porous plate 7, apart from the exhaust type that sends the air flow from below the porous plate 7 as shown in the figure.
As shown in FIG. 2, the perforated plate 7 has a slit-like long hole 3 opened over almost the entire surface, and is surrounded by a standing wall 33 that opens a discharge port 31 for small specific gravity grains such as rice grains. It has a structure. On the other hand, a large specific gravity discharge port 5 such as a glass piece is mainly provided at the upper end, and the large specific gravity particles can be discharged by opening and closing the shutter plate 35.
[0028]
A raw material supply port 37 formed by a combination of the flow rate control means 11 and the diffusion supply means 15 is provided at an appropriate position above the inclination of the perforated plate 7, while diffusing a group of grains such as rice grains over a wide area, as shown in FIG. It is made to flow down to the flow area d shown by the oblique line. As described in the section of the above-mentioned operation, this is for making the thickness of the lower layer of the particle group uniform. An example of diffusion and flow down is shown. However, this flow area may be formed by various diffusion forms, and is not limited to this example.
[0029]
As shown in FIG. 3, this diffusion supply means 15 has a structure in which a rough wire net 41 is provided in two steps in the upper and lower stages in the shape of a horse's back inside a reverse funnel-shaped guide member 39 that opens toward the upper surface of the perforated plate 7. It is. In addition, a funnel-shaped raw material receiving member 43 is provided on the upper portion of the guide member 39. ² 5.5m per hour ^Three The following granule groups are supplied. The particle group supplied to the raw material receiving member 43 passes through the eyes of the two wire meshes 41, 41 and falls down, or is bounced by the meshes and slides down to the side. It spreads in the entire direction or in the front-rear direction and flows down on the perforated plate 7. Since the diffusion supply means 15 has a function of diffusing and flowing down the particle group on the porous plate 7 as described above, it can take various structures other than this example.
[0030]
As described above, the flow rate control means 11 sets the flow rate of the particle group flowing down to the porous plate 7 to 1 m of the porous plate area. ² 5.5m per hour ^Three The following control is performed, not limited to the present embodiment, and any position may be used as long as it is a pre-process of the diffusion supply means 15, and a known flow valve or the like may be used. For example, the area of the porous plate 7 is 0.34 m. ² In this case, when this is applied to the rice grain group, the flow rate by the following calculation may be set. 5.5 (Control flow rate: m ^Three /Hour)×0.78 (apparent specific gravity of rice grains) × 0.34 (area of perforated plate 7: m ² ) = 1.45 (flow rate: ton / hour). In other words, the flow rate may be controlled to 1.45 tons or less per hour, and if this flow rate is exceeded, the sorting rate decreases. The smaller the specific gravity difference, the smaller the flow rate may be.
[0031]
In such a granular material sorting apparatus 1, it is most desirable that the optimum air volume can be monitored with respect to the long hole of the porous plate 7 as described above. However, because of the structure of this device, measurement during its operation is impossible, so it was set while measuring by the method shown in FIG. 4 in the idling state. As shown in the figure, the raw material supply port 37 is removed and blown by the blower means 13 from under the porous plate 7, and the lower end of the cylindrical vinyl sheet 47 is placed on the bottom wall 33 of the porous plate 7 by a tape 49 so as not to escape the wind. Then, all the air blown out from the long hole 3 of the perforated plate 7 was allowed to pass through the exhaust tube 53 provided at the upper end of the vinyl sheet 47, and the passing air amount was measured by the anemometer 55. At this time, the inner diameter of the exhaust pipe 53 was adjusted so that the wind speed was in the range of 5 m to 8 m per second so that the cross-sectional area of the exhaust pipe 53 was too small and excessive back pressure was not applied. As a result, when the granule is a rice grain, 1 m of the perforated plate area during idling ² 30m per minute ^Three ~ 45m ^Three It was measured that the air flow rate was appropriate.
[0032]
In the present invention as described above, the conditions may be determined by the following tendency in each of the above condition setting ranges. (1) The more inclined the surface of the granular material, the more inclined θ _P Make it smaller. (2) The larger the granular body, the longer the amplitude (reciprocating distance) of the porous plate 7 is increased. (3) As the amplitude of the porous plate 7 is shorter, the number of reciprocating motions per minute is increased. (4) The air flow rate per unit time passing through the long hole 3 of the porous plate 7 is decreased as the number of reciprocating motions per minute of the porous plate 7 is increased or the specific gravity of the granular material is decreased.
[0033]
Hereinafter, the operation of the present apparatus will be described in more detail with reference to FIGS. 1 to 3 by taking as an example a case where glass pieces are mixed in rice grains. The perforated plate 7 is 0.34 m as described above. ² The one of the area is used. First, after the present sorting apparatus 1 is idled and the rice grain group is continuously supplied from the flow rate control means 11 to the diffusion supply means 15, the rice grain group is diffused by the metal nets 41 and 41 having a rough net shape. It falls in a wide area and evenly in the falling area d on the perforated plate 7. Here, D of the porous plate 7 _V And the reciprocating motion up and down shown in the direction, and the air flow blowing in the diagonally upward direction opposite to the discharge port 31 of the small specific gravity particles from the countless long holes 3 opened in the perforated plate 7. Due to the action, the rice grain group that has fallen to the position of the flow-down area d of the perforated plate 7 first moves in the direction of the discharge port 5 of the large specific gravity grains, and becomes a layer having a thickness of about 1 cm and the tip (left end in the figure) It gradually spreads downward in a layered manner (right direction in the figure) while filling, and when the entire surface of the porous plate 7 is filled, it overflows from the discharge port 31 of small specific gravity particles and flows down to the outside of the porous plate 7, Thereafter, as long as the supply of the rice grain group continues, the rice grain group continues to flow from the downstream area d to the discharge port 31 for the small specific gravity grains. However, in this flow state, not all of the layer having a thickness of 1 cm flows in the downward direction of the slope, but the upper layer portion flows downward in the slope (right side of the figure), while the lower layer portion reversely inclines upward (see the figure). Gradually move to the left).
[0034]
It is D of perforated plate 7 _V This is because the reciprocating motion in the diagonally up and down direction shown in FIG. 5 and the air flow blown out from the numerous long holes 3 are blown out in the direction of the large specific gravity discharge port 5. And the lower layer part moves to the direction of the discharge port 5 of the large specific gravity grain, but the rice grain of the small specific gravity in the rice grain group floats in the meantime, toward the discharge port 31 of the small specific gravity grain in the opposite direction. And flow. And in this flow process, D _V Among the rice grains that flow on the perforated plate 7 by the reciprocating motion in the diagonally up and down direction, a glass piece having a specific gravity slightly larger and smaller in volume than the rice grains is the same as in the case of soybean and sesame as described above. It gradually sinks to the lower part of the. At this time, as described above, a part of the air flow that blows out from the many long holes 3 of the perforated plate 7 blows through the layer of the rice grain group from the bottom to the top, thereby forming a gap between the rice grains, and friction with the rice grains. Reduced to promote the smooth settlement of the glass piece. In this way, the glass piece gradually sinks in the layer of rice grains by receiving the volume selection action by the vibration of the reciprocating motion, but the sinking speed is extremely slow. However, in the present invention, the flow rate of the rice grains flowing on the porous plate 7 is 1 m of the porous plate area. ² 5.5m per hour ^Three Since the moving speed of the rice grain group is slow, the glass particles having a slow settlement speed will finish sinking to the lower layer of the rice grain group before reaching the discharge port 31 of the small specific gravity grain due to the volume selection action by vibration. . And if it sinks to the lower layer part of a rice grain group, a glass piece will be gradually sent to the direction of the discharge port 5 of a large specific gravity grain by the air flow which blows off from the many long holes 3, and a reciprocating motion. At this time, the flow rate of air blown from the many long holes 3 of the porous plate 7 is 1 m of the porous plate 7 area. ² 30m per minute ^Three ~ 45m ^Three Since the amount is much smaller than in the past, for example, even a glass piece having a small volume and a large surface area contained in the rice grain group is not blown upward.
[0035]
Further, the rice grain group flowing down on the porous plate 7 is diffused by the action of the diffusion supply means 15 and flows almost uniformly in the wide area of the flowing region d of the porous plate 7, so it is partially necessary. An overly thick layer that is thicker than that is not formed. Therefore, the air flow that flows intermittently due to the reciprocating motion of the perforated plate 7 and flows through a slight gap between the rice grain group and the perforated plate 7 is not obstructed, and the air flow is unevenly distributed by hitting the thick layer portion. No glass piece is blown above the rice grain group.
That is, this glass piece is blown up when the layer of rice grains becomes partly thick, a heavy pressure is applied to that part, and even if the porous plate 7 is reciprocating, the lower part of the thick layer is in close contact with the porous plate 7. As a result, the air flow that has flowed through the lower part of the rice grain group up to that part is sealed off, so the air flow is blown up from the bottom of the rice grain group at that position, It is generated by blowing the glass piece that has sunk in the lower layer part to the upper layer part of the rice grain group.
Accordingly, the supply from the diffusion supply means 15 prevents the overlying layer from being generated, and acts to move the glass piece that has settled in the lower layer portion of the rice grain group as it is without being lifted to the upper layer portion. The piece of glass that has smoothly moved to the upper side of the slope in this way eventually reaches the discharge port 5 (the left end in the figure) of the large specific gravity particle, and the glass piece or stone particle (the stone particle has a specific gravity) that moves from various places of the perforated plate 7. Since it is large, it is easily sorted) and stays in the vicinity. When a certain amount of large specific gravity particles accumulate, the shutter 35 is pulled to open the discharge port 5 for large specific gravity particles, and foreign matter is discharged to the outside. Of course, the shutter 35 is left open, and foreign matter does not have to stay.
[0036]
And in this invention, since the grain size selection which sorts out the large foreign material from a rice grain group can also be used together, a foreign material can be removed more completely. In addition, since the present invention sorts mainly by the difference in volume, it goes without saying that it can cope with not only sorting of rice grains but also sorting of all other grains.
[0037]
【The invention's effect】
According to the present invention, the following excellent effects are brought about mainly by the description in the section of the above action.
The grain sorting method of the present invention is realized for the first time by a completely new concept that does not correspond to any of the conventional methods, that is, the concept of volume sorting, in sorting and removing foreign substances mixed in the grain. Therefore, with a very simple method and device structure, for example, glass fragments in rice grains and small specific gravity stone grains such as pumice, which were previously said to be impossible to sort and remove, have a very small specific gravity difference and large grain sorting. However, foreign substances having a small volume that cannot be removed can be efficiently removed. Especially when applied to rice grains, the effects brought by the food industry, which is extremely afraid of foreign matter, is immensely great.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an explanatory diagram showing an example of the structure of a granule sorting apparatus for realizing the present invention.
FIG. 2 is an explanatory diagram showing an example of the structure of a perforated plate used in the granule sorting apparatus of the present invention.
FIG. 3 is an explanatory diagram showing an example of the structure of the diffusion supply means used in the granule sorting apparatus of the present invention.
FIG. 4 is an explanatory diagram showing a method for measuring the flow rate of air passing through a perforated plate in the granule sorting apparatus of the present invention.
[Explanation of symbols]
1 Granule sorter 35 Shutter plate
3 Long hole 37 Raw material supply port
5 Large specific gravity discharge port 39 Guide member
7 Perforated plate 41 Wire mesh
9 Driving means 43 Raw material receiving member
11 Flow control means 47 Vinyl sheet
13 Blowing means 49 Tape
15 Diffusion supply means 51 Guard plate
17 Housing 53 Exhaust tube
19 Electric motor 55 Anemometer
21 Camshaft pulley
23 Transmission means
25 cams
27 Cam Follower
29 fans
31 Small specific gravity outlet
33 Standing wall

Claims (5)

A number of long holes whose opening direction is oblique to the plate surface are opened, and are inclined in the same direction as the opening direction of the long holes in a direction of 7 ° to 14 ° with respect to the horizontal direction. The perforated plate provided
The reciprocating motion is performed 350 to 650 times per minute with an amplitude of 6 mm to 12 mm in the same direction as the inclined direction of the perforated plate and in the direction of 40 ° to 90 ° with respect to the horizontal direction. Against the air flow from the bottom to the top,
A grain group in which a glass piece having a specific gravity slightly larger and smaller in volume than the rice grain and having many sharp irregularities on the surface is mixed in the rice grain on the perforated plate from the upper side of the slope to 1 m of the perforated plate area. ^A method of selecting granules to flow down at a flow rate of 5.5 m ³ or less per ² per hour. The air flow rate passing through the long holes of the porous plate, screening methods of the granules according to claim 1, wherein the range of 1 m ² per minute per 30m ³ ~45m ³ of the porous plate area during idling.   A method for selecting particles, wherein the method for selecting particles according to claim 1 and the method for removing particles according to the difference in size between the particles and the particles are used in combination. A number of long holes whose opening direction is oblique to the plate surface are opened, and are inclined in the same direction as the opening direction of the long holes in a direction of 7 ° to 14 ° with respect to the horizontal direction. A perforated plate provided;
Drive means for reciprocating the perforated plate in the same direction as the inclination direction and in the direction of 40 ° to 90 ° with respect to the horizontal direction with an amplitude of 6 mm to 12 mm;
The amount of flow of particles into the perforated plate, that is, the amount of particles mixed with glass pieces that have a slightly larger specific gravity and a smaller volume than the rice grains, and that have many sharp irregularities on the surface, A flow rate control means for controlling to below 5.5 m ³ per hour per 1 m ^{2 of} area;
A blower means for passing an air flow from the bottom to the top of the long hole of the perforated plate. With respect to the long hole of the porous plate from the blowing means, granules sorting apparatus according to claim 4, wherein passing the porous plate 1m per per ² minute area 30m ³ ~45m ³ of the air flow during idling.

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