JPH0697888B2 - Seed coating equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an apparatus for producing coated seeds. More specifically, the present invention relates to a seed coating device used for coating seeds one by one with a powder material for coating and the like.

[0002]

2. Description of the Related Art By coating seeds,
The seeds can be easily handled, and the seeds can be stored for a long time. In addition, since the coated seeds can be mechanically sown, this not only helps to save the seeding amount, shortens the seeding time, saves the thinning labor, but also keeps the intervals between the plants so that the seeds can grow. It can be expected to have advantages such as a uniform product, and eventually a uniform shape and quality of the harvested product and less waste.

In order to facilitate mechanical sowing, it is necessary to coat seeds with an inorganic substance or the like to increase the bulk.

Conventionally, as a method for producing coated seeds, an aqueous solution of a water-soluble binder such as starch, PVA, CMC, MC, HPC and gelatin, and diatomaceous earth, aluminum hydroxide, barium hydroxide, magnesium hydroxide, calcium sulfate, Using powder materials such as basic magnesium carbonate, silica, calcium sulfite, calcium carbonate, calcium silicate, illite, halosite, microsite, vermiculite, peat moss, sand and clay,
A method is known in which both are alternately applied to the surface of seeds for coating.

That is, seeds are placed in a coating container, and while the coating container is rotated, an aqueous binder solution is applied to the surface of the seeds by a spray method or the like, and then a powder material is charged to bond the powders and the seeds. By repeating such an operation, the surface of the seed is coated with the powder material to a desired thickness.

[0006]

However, the commonly known seed coating container is merely a container having an integral shape. When seeds are coated using such a conventional coating container, the coating container is inclined, so that the flow of the seeds is apt to occur and it is difficult to coat the seeds one by one. The volumetric efficiency of the seeds is smaller than that of the seeds, and the flow condition of the seeds becomes extremely poor when the number of rotations of the coating container is increased, which tends to cause variations in the particle size distribution and lower productivity. Since the coat layer is soft, there were problems such as the coat layer cracking easily during mechanical seeding, automatic filling, or transportation.

[0007] Further, it is necessary for the coated seed to absorb the moisture in the soil so that the coating layer is easily disintegrated,
As a result, the amount of water-soluble binder used is naturally limited.

On the other hand, the present inventors have found that CMC (serogen 6
As a device for coating seeds with a binder such as A, Daiichi Kogyo Seiyaku Co., Ltd., an attempt was made to divert a centrifugal fluidized coating granulator for producing a preparation, granular food, or the like. However, as a result of experiments, it has been found that it is not suitable to use the above-mentioned coating granulator for preparations and the like as a coating apparatus for seeds.

That is, the above-mentioned coating granulator for preparations and the like is a granulator for producing tablets and the like, and even though it is effective for granulating tablets and the like, it is a biological and special It has been revealed that the coating of seeds having different shapes and sizes causes the following new problems.

The seeds dried abnormally during coating and the powder material did not adhere sufficiently to the seeds. When a large amount of a water-soluble binder was added to solve this problem, the coating layer varied and the coating seed particle size also varied. The water in the cells of the seeds was excessively evaporated during the coating, and the growth of the seeds was inhibited or the seeds were killed. When very light weight (average weight per grain varies depending on the type of seed, about 0.013 to 0.00032 g) and a flat shape that is susceptible to wind resistance is put into the coating container, the seed will be Without causing sufficient frictional contact pressure with the inner wall surface of the fixed container, the particles flew upward, and good seed coating was not performed.

On the other hand, a granulating machine for pharmaceuticals having a structure in which the upper surface of a rotating dish-shaped portion provided at the bottom of a fixed cylindrical container is formed as a flat surface over the entire surface (for example, Japanese Patent Publication No. 47-477).
(See Japanese Patent Laid-Open No. 94) was diverted for seeds. However, in the structure of the rotating dish-shaped portion, when extremely lightweight and specially shaped seeds are put into the coating container, the seed group is unlikely to generate a whirlpool circulation flow during coating. As a result, the coating layer formed on the surface of the seed is too soft, and the coating layer having a uniform thickness cannot be obtained, which causes variations in the size of the coated seed.

[0012] Furthermore, a granulating machine for preparations (see, for example, Japanese Patent Publication No. 46-22544) having a structure in which the upper surface of the rotary dish-like portion is largely curved substantially from the central portion to the outer peripheral end is used for seeds. It was also tried to divert as.
However, in the structure of the rotating dish-shaped portion, not only the seed coat layer does not have an appropriate hardness, but also the particle size of the coated seed varies. The inventors of the present invention conducted repeated studies to investigate the cause, and when the rotary dish-shaped portion was largely curved, the seeds on the rotary dish-shaped portion were allowed to reach the outer peripheral edge portion. , As a result of the centrifugal force acting on the seeds being greatly attenuated and the seeds not hitting the inner wall surface of the fixed cylindrical container strongly, individual seeds may not be given sufficient frictional contact pressure with the wall surface of the fixed cylindrical container. I determined that it was the cause.

[0013]

[Means for Solving the Problems] The present inventors have focused their attention on the above-mentioned problems and have conducted earnest research to develop a seed coating apparatus having no difficulty. As a result, a powder material and a water-soluble binder are obtained. In a device for coating seeds using, a fixed cylindrical container having an open type and a bottom of the coating chamber having a closed structure, and an inoculum surface provided at the bottom of the fixed cylindrical container and having a smooth inoculum surface are formed. The present invention has led to the invention of a seed coating apparatus (Claim 1) characterized by having a rotating dish-shaped portion.

Further, in an apparatus for coating seeds using a powder material and a water-soluble binder, a fixed cylindrical container which is an open type and whose bottom of the coating chamber has a closed structure, and this fixed cylindrical container The inoculum surface of the central surface area is formed in a flat surface at the bottom of the, and the inoculum surface of the outer peripheral edge side connected to this central surface area forms a gentle rising curved surface toward the outer peripheral side. The present invention has led to the invention of a seed coating apparatus (claim 2), characterized in that it has a rotating dish-shaped portion formed so as to draw.

[0015]

EFFECT OF THE INVENTION According to the seed coating apparatus of the present invention described above, the particle size distribution of the coated seed is small and a uniform particle size is obtained, the productivity is high, and the coat layer has an appropriate hardness. And has excellent disintegration in water,
It is possible to easily produce seeds that are evenly coated one by one.

Further, as a result of the powder material being sufficiently adhered to the seeds, it is possible to further improve the uniformity of the thickness of the coat layer, and thus the uniformity of the particle size of the coated seeds. In addition, it is possible to avoid growth inhibition and death of seeds. Besides,
Even if the seeds are extremely light and have a generally flat shape or other special shape that is easily affected by wind, the seeds in the coating chamber generate a whirlpool-like vortex circulation flow, and Since a sufficient frictional contact pressure can be obtained between the inner wall surface of the fixed container side, it becomes easier to form a coat layer of appropriate hardness one grain by one grain on the surface of all seeds in the coating chamber. The effect is obtained.

[0017]

An embodiment of the seed coating apparatus according to the present invention will be described in detail with reference to the drawings.

As shown in FIG. 1, a rotary plate-shaped part 1 having a bottom plate part for receiving a large amount of seeds to be put into a container and having a smooth inoculum surface, and the rotary plate-shaped part 1 And a fixed cylindrical container 2 for smoothing the flow state of seeds when rotating at a high speed and preventing the seeds from jumping out by centrifugal force.

As is clear from FIGS. 1, 4, and 5, the fixed cylindrical container 2 has an open upper end, so that the inside of the fixed cylindrical container 2 is kept at room temperature. On the other hand, the bottom of the coating chamber is formed to have a closed structure, and the coating is performed under the non-convection condition of air.

With such a structure, since the inside of the coating chamber is kept at room temperature, abnormal drying of the seed during coating and excessive evaporation of water in the seed cells are avoided. In addition, since the bottom of the fixed cylindrical container 2 is formed so that the bottom of the coating chamber has a closed structure, even if the seed has a generally flat shape that is susceptible to wind resistance, the seed is blown off during coating. There is no chance of being caught or flying around.

The nozzle of the spray gun 8 is a rotating dish-shaped portion 1.
Facing the inside of the fixed cylindrical container 2 almost at the boundary between the fixed cylindrical container 2 and the fixed cylindrical container 2, and spraying the water-soluble binder from the spray gun 8 onto the seeds intermittently or continuously, The powder material is introduced intermittently or continuously from the powder material feeder 9 facing the inside so that the surface of each seed is coated with the powder material.

The rotating dish-shaped part 1 having a smooth inoculum surface may have a structure in which the whole inoculum surface is formed into a flat surface as shown in FIG. According to
The rotating dish-shaped portion 1 having the structure shown in FIG. 3 is used.

The rotary dish-shaped portion 1 shown in FIG. 3 has a shape in which the outer peripheral side of the upper surface of the flat plate is raised and curved so as to draw a gentle curve upward. In other words, the rotating dish-shaped portion 1 provided at the bottom of the fixed cylindrical container 2 has the inoculum surface in the central surface area formed on the flat surface 1a, and the outer peripheral edge portion continuous with the central surface area. The inoculum surface is formed so as to draw a gentle rising curved surface 1b toward the outer peripheral side. With such a structure, even in the case of extremely lightweight and specially shaped seeds, a whirlpool flow circulation flow easily occurs in the coating chamber, and the centrifugal force acting on the seeds is almost attenuated. The seeds reach the inner wall surface of the fixed cylindrical container 2 without moving.

The number of rotations of the rotary dish 1 having a smooth inoculum surface should, of course, be selected as an optimum value depending on the size of the apparatus, the amount of seeds, the shape of seeds and the size thereof. Generally less than 300r.pm, preferably 150-
250 rpm is good. Rotation speed is adjusted by the variable speed electric motor 3
Alternatively, it can be performed by a suitable transmission.

The rotary dish 1 having a smooth inoculum surface is
It is configured to be removable from the drive shaft 4 of the variable speed electric motor 3. This is because, as described above, it is necessary to select and use the shape of the rotary dish-shaped portion 1 having a smooth inoculum surface according to the seed preparation amount, the shape of the seed and the size thereof.

When coating extremely light and flat seeds, such as lettuce and carrot, one by one, it is particularly effective to use the rotary dish 1 shown in FIG.

The rotating dish-shaped portion 1 is formed so that the inoculum surface on the outer peripheral edge side which is continuous with the central surface area of the rotating dish-shaped portion forms a gentle rising curved surface 1b toward the outer peripheral side.
Even if the individual seeds are extremely light and have a flat shape, this seed group can be smoothly made into a whirlpool-like flow state. As a result, the particle size distribution of the product becomes smaller,
The seeds are surely coated one by one.

Since the inoculum surface in the central surface area of the rotary dish 1 is formed on the flat surface 1a, the centrifugal force generated by the rotation of the rotary dish 1 is on the rotary dish 1. The large effect is exerted on the seed, and the centrifugal force is hardly attenuated until the seed reaches the vicinity of the curved surface 1b of the rotary dish-shaped portion 1. As a result, a large frictional contact pressure is secured between the individual seeds and the inner wall surface of the fixed cylindrical container 2.

The types of seeds coated by using the seed coating apparatus of the present invention are as follows.

[0030]

[Table 1]

As a result of seeds growing to a predetermined size as a result of coating for a certain period of time by the seed coating apparatus shown in FIG. 1, the shoots 6 are transferred from the chute 6 to the saucer 7 via the dampers 5 on the side walls of the fixed cylindrical container 2. It is configured so that it can be taken out. The mounting position of the chute 6 may be set on the side wall near the bottom of the fixed cylindrical container 2 as shown in FIG. 1, but in the case of coating in a continuous operation system, the coated seeds of the fixed cylindrical container 2 are coated. It can also be taken out as an overflow form from above.

The present invention is a seed coating apparatus having the above-mentioned structure, and FIG. 4 shows a state in which the coating apparatus is stopped, and the height H of the effective volume entering the fixed cylindrical container 2 is H. Is a number that increases as the seed is coated.

Further, FIG. 5 shows a state in which the seed coating apparatus is in operation. Inside the fixed cylindrical container 2, the seed group forms a vortex state like a "nawa" and rotates while flowing uniformly, while the water-soluble binder is evenly applied to the surface of each seed. Therefore, local agglomeration of the powder material does not occur. Therefore, the particle size distribution of the coated seed is narrowed, and the volume efficiency is 1.5 to 3 times as high as that of a commonly used coating container having the same diameter.

Further, when the apparatus of the present invention is used, the water-soluble binder is applied to the surface of the powder to homogenize the bonds between the powders and between the particles / seed, and there is no partial bond defect, so that the entire structure is improved. As a result, a coated seed having high hardness can be produced.

It should be noted that the coated layer produced by using the apparatus of the present invention has a coat layer which is easily broken by the water content in the soil at the time of sowing, and has no effect even when compared with the case of sowing ordinary uncoated seed. Has no effect on germination and growth.

The fact that many properties are simultaneously improved in this way has never been known in the past, and is truly surprising.

The powder material for coating applied to the apparatus of the present invention is usually used as described above, but as a result of experiments, the average particle diameter thereof is preferably 10 μm or less, preferably Is preferably 1 μm or less.

Although a water-soluble binder is also commonly used, its addition amount can be 0.1 to 20% by weight based on the powder material for coating,
It is preferably 0.5 to 5% by weight.

Experimental examples for further clarifying the present invention are shown below, but the present invention is not limited to these experimental examples.

[Experimental Example 1] A seed coating apparatus having the structure shown in FIG. 1 was used, and a rotating dish-shaped portion having a smooth inoculum surface was 200 mmφ having the structure shown in FIG. Using a coating container having a size of 200 mmφ, 500 g of Chinese cabbage seeds were charged, and coating was performed until the average particle size grew to 3.0 mmφ.

The powder material was 3500 g of diatomaceous earth having an average particle size of 5 μ, and the binder was 1500 cc of a 2% by weight aqueous solution of CMC (Serogen 6A Daiichi Kogyo Seiyaku). The obtained results are as shown in Table 2.

[0042]

[Table 2]

[Experimental Example 2] The seed coating apparatus having the structure shown in FIG. 1 was used, and the rotating dish-shaped portion having a smooth inoculum surface was 200 mmφ having the structure shown in FIG. Using a coating container having a size of 200 mmφ, 200 g of ginseng seeds were charged and coating was performed until the average particle size grew to 3.5 mmφ.

The powder material used was 2500 g of diatomaceous earth having an average particle size of 5 μ, and the binder used was 1200 cc of a 2% by weight aqueous solution of CMC (Serogen 6A Daiichi Kogyo Seiyaku). The obtained results are as shown in Table 3.

[0045]

[Table 3]

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a seed coating apparatus showing an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view showing an example of the structure of a rotary dish-shaped portion provided in the coating apparatus.

FIG. 3 is a vertical cross-sectional view showing another example of the structure of the rotary dish-shaped portion provided in the coating apparatus.

FIG. 4 is a vertical cross-sectional explanatory view showing a stopped state in which a seed coating operation is performed using the seed coating apparatus of the present invention.

FIG. 5 is a vertical cross-sectional explanatory view showing an operating state in which a seed coating operation is performed using the seed coating apparatus of the present invention.

[Explanation of symbols]

 1 Rotating Dish 1a Flat Surface 1b Curved Surface 2 Fixed Cylindrical Container 3 Variable Speed Electric Motor 4 Drive Shaft 5 Damper 6 Chute 7 Saucepan 8 Spray Gun 9 Powder Material Feeder

Claims (2)

[Claims] 1. An apparatus for coating seeds using a powder material and a water-soluble binder, which is an open type and has a fixed cylindrical container whose bottom in the coating chamber has a closed structure. A seed coating device, comprising: a rotating dish-shaped portion provided on the bottom of the, and having a smooth inoculum surface. 2. A device for coating seeds using a powder material and a water-soluble binder, which is an open type and has a fixed cylindrical container formed so that the bottom of the coating chamber has a closed structure, and the fixed cylindrical container. The inoculum surface of the central surface area is formed in a flat surface at the bottom of the, and the inoculum surface of the outer peripheral edge side connected to this central surface area forms a gentle rising curved surface toward the outer peripheral side. A coating device for seeds, comprising: a rotating dish-shaped portion formed so as to be drawn.