JPS6365372B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an improvement of a dry granulation device that is widely used in the pharmaceutical, agrochemical, food, and other industries. The present invention relates to a dry granulation device consisting of a combination of a type compression molding device, a gear type coarse granulation device, and a roll granulator. Roll compression molding and granulation equipment are generally used as a dry granulation method, which is a method of granulating powder containing components that are easily decomposed by water. Figure 1 shows an example of this, with powder 2 in supply hopper 1.
Forming rolls 4-a, 4-b with vertical screw 3
The powder 2 is pressed into the powder 2 and compressed with the optimum pressure to form a plate-shaped molded product 5. This plate-shaped molded product 5 is crushed by the rotational impact force of the rotor 6 using a rotor-type crusher (consisting of a rotor 6 and a punching plate 7), and the crushed material is rubbed against the punching plate 7 by the rotational centrifugal force. By passing through the holes, predetermined coarse granules 8 can be obtained. Furthermore, a roll-type crushing device commonly known as a roll granulator, that is, three stages of rollers 9-1-a, 9-1-b, 9-2-a, each having vertical grooves with a triangular cut section, is used. ,9-2-
b, 9-3-a, 9-3-b (Figure 3 shows a single-stage roller, but the groove pitch P is, for example, 3 mm, 2 mm, and 1 mm from the top of the 3-stage roll). Granules 10 are obtained. Note that depending on the physical properties and the required size of the granules, two-stage rollers 9 may be used.
-1-a, 9-1-b, 9-2-a, 9-2-b
In some cases, equipment measures may be taken. Also, this granule 10
Since the powder contains fine powder generated during coarse crushing or granulation, it is generally classified using a sieving device, and the fine powder is returned to the supply hopper 1 for reuse. The conventionally used devices described above have the following drawbacks. 1. Since a large amount of fine powder is generated, processing capacity is reduced and problems with powder adhesion are likely to occur. There are two main reasons for this. The molding rolls 4-a and 4-b have the structure shown in FIG. 2, and the plate-shaped molded product 5 thereof is susceptible to variations in molding pressure transmission and powder supply, and is hard at the center and soft at both ends. Therefore, it is difficult to maintain operation under optimal conditions during coarse crushing and granulation. As a method for converting a plate-like molded product having a large volume into granules having a small volume, the method relies only on a method that generates a large amount of fine powder, in which the crushed material is rubbed against the punching plate 7 by the impact of a roller and the resulting centrifugal force. There is. In addition, in a large-sized machine, the width of the plate-shaped molded product 5 becomes large, and this becomes an even more serious drawback. 2 Three stages of rollers 9-1-a, 9-1-b,
9-2-a, 9-2-b, 9-3-a, 9-3
As mentioned above, the granulator consisting of B has a small groove pitch P of the triangular vertical grooves, and the groove spacing between opposing rollers is an important factor in granulation, so high manufacturing precision is required. Become. Therefore, equipment costs are extremely high. On the other hand, during operation, powder adheres to the troughs of the vertical grooves, so currently a plate-shaped scraper is generally used to remove it. However, it is difficult to achieve high precision due to its structure, and the effect is not always achieved. The device of the present invention was obtained as a result of intensive studies aimed at improving such conventional devices. The present invention will be explained below based on the drawings. FIG. 4 shows a plan elevational view of an improved forming roll of the roll-type compression molding apparatus of the present invention, and FIG. 5 shows a plan sectional view of a molded product obtained by the roll of FIG. 4. Figure 4
As shown in the figure, in the present invention, a plurality of rows of circumferential triangular prism-shaped ridges 12 are provided on the forming surface of one of the pair of rolls. It is effective for the ridges 12 to have an equilateral triangular shape or a shape close to it, and the intervals provided on the roll forming surface are preferably equal intervals, and the pitch B of the ridges varies depending on the size of the target granulated product. Considering granulation in the pharmaceutical industry and manufacturing accuracy, approximately 1 to 6 mm.
(Effect confirmed at 4 mm) is preferable. When the roll-type compression molding apparatus of the present invention is used, a plate-shaped molded product having the shape shown in FIG. 5 can be obtained. In the case of pitch B = 4 mm, T ₁ = 1.2 mm and T ₂
= 0.3 to 0.4 mm, the part corresponding to the bumps is very thin, and when it is applied to the gear-type coarse granulation machine shown in Figure 6 below, the T ₂ part is cut off by the shot, forming a noodle shape called "Himokawa Udon". Good coarse granules can be obtained by aligning and crushing the particles. The cross section of the plate-shaped molded product in FIG. Since it is less susceptible to variations in pressure transmission and powder supply, uniform molding can be achieved and the drawback 1 of the conventional dry granulation apparatus described above can be improved. Figure 6 is a mechanical diagram of a gear-type coarse crushing and granulating device in which two gears 13-a and 13-b are arranged in parallel.The distance k between the gear teeth of both gears is the thickness of the plate-shaped molded product
Adjusted to within 3/4 of T ₁ . The gear teeth may be arranged with the peaks facing each other or offset like peaks and valleys, but it is particularly effective to combine the peaks. Mechanically, this device uses shearing force, so there is very little generation of fine powder.
(Only the gear 13-a side is shown in Figure 6.) By meshing with the gears 13-a and 13,
-B deposits can be removed and stable coarse granules can be produced. However, the gears 13-a, 13-b and the scraping gear 14 may be held with an appropriate clearance between them to prevent wear. The scraping gear 14 is incorporated via a bearing into a shaft 15 that performs reciprocating motion as indicated by the arrow S using a known method such as a cylinder or cam mechanism, and the scraping gear 14 is installed on the entire surface of the gear teeth of the gears 13-a and 13-b. It seems to be prevalent periodically. Further, the gear teeth of the gears 13-a, 13-b and the scraping gear 14 may have the shapes shown in A and B of FIG. 7, and particularly good results have been obtained with B. Preferable P ₁ , θ ₁ , t ₁ , P ₂ , θ ₂ and t ₂ are as shown in Table 1.

[Table] Next, by using the improved forming roll shown in Fig. 4 together with the gear-type coarse granulation device shown in Fig. 6, the coarse granules become stable as described above, and as a result, generally the The granulator in Figure 1, which required three stages, has two rolls 9.
-2-a, 9-2-b, 9-3-a, 9-3-b
Or one stage roll 9-3- depending on powder physical properties
Equipment can be reduced to a, 9-3-b. Furthermore, depending on the size of the granules required, by installing two or three stages of the newly developed gear-type coarse granulator, it is possible to produce granules without using a conventional very expensive granulator. In both cases, it is possible to greatly increase yield and reduce equipment costs. Table 2 shows the distribution of granules produced by the conventional dry granulation apparatus and the granules produced by the apparatus of the present invention.

[Table] Add further explanation on how to scrape off deposits. Although the method for the gear type roll was explained in Fig. 6, the method for the vertically grooved roll shown in Fig. 1 used as a conventional granulator can also be applied to the vertically grooved gear teeth as shown in Figs. 8 and 9. Notch 17 on the same gear tooth
It is possible to scrape off deposits by meshing the vertical gear rolls 16 for scraping, each having an appropriate clearance (an appropriate clearance may be maintained in consideration of the wear of the gear teeth and notches of both rolls). becomes. In addition, in FIGS. 8 and 9, the roll 9-1-a
Although only the vertical gear roll 16 for scraping is shown, the same applies to the roll 9-1-b. Furthermore, the rolls 9-2-a, 9-2- in Fig. 1
There is no need to explain that the same applies to b, 9-3-a, and 9-3-b. As described above, the apparatus according to the present invention can solve all of the above-mentioned drawbacks of the conventional dry granulation apparatus.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a conventional dry roll granulation device, Fig. 2 is a plan elevation view of a conventional forming roll, and Fig. 3 is a plan elevation view showing one stage of fluted rolls of a roll granulator. , FIG. 4 is a plan elevational view of the improved forming roll according to the present invention, FIG. 5 is a plan cross-sectional view of a molded product obtained by the improved forming roll of FIG. 4, and FIG. 6 is a gear type coarse granulation granulator according to the present invention. A perspective view of the device and the scraping gear device, FIG. 7 is an elevational view showing the gear teeth in the device of FIG. 6, FIG. 8 is a perspective view showing the mechanism of the scraping gear device for the fluted roll,
9 is a plan cross-sectional view showing a portion of FIG. 8.

Claims (1)

[Claims] A roll-type compression molding device, a gear-type coarse crushing and granulating device, and a roll granulator, in which a plurality of rows of triangular prism-shaped ridges surrounding the circumference are provided on the surface of one roll of a pair of rolls. A dry granulation device consisting of a combination of 2. The dry granulation device according to claim 1, wherein a gear for removing deposits that can reciprocate from side to side is incorporated in the gear groove of the 2-gear type coarse crushing and granulation device. 3. The dry granulation device according to claim 1, wherein a gear for removing deposits is incorporated in the groove of the vertically grooved roll of the roll granulator.