JPS59162937A - Dry granulating apparatus - Google Patents

Abstract

PURPOSE:To enhance treating capacity by reducing the generation of a fine powder, by combining a roll type compression molding apparatus wherein plural lines of a trigonal prism shaped projections are provided to the surface of one roll among a pair of rolls, a gear type coarsely grinding and screening apparatus and a roll type grinding apparatus. CONSTITUTION:Trigonal prism shaped projections 12 are provided to the molding surface of one roll 11a among a pair of the rolls of a roll type compression molding apparatus in a plurality of lines so as to surround the circumferential surface thereof and a powder is supplied to the nip with the opposed roll 4b to obtain a grooved plate shaped molded product. In the next step, the peak interval (k) between each pair of teeth of the gears 13a, 13b of a gear type coarsely grinding and screening apparatus is adjusted to about 3/4 on the basis of the thickness of the plate shaped molded product and said molded product is ground to form coarse granules while the adhered substance is removed by a scraping gear 14. In addition, the above mentioned coarse granules are passed through roll type grinding apparatuses 9-1a, 9-1b to obtain desired granules. By this mechanism, a granule yield is largely enhanced and the stage numbers of the roll type grinding apparatuses can also be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a dry granulation device widely used in the pharmaceutical, agrochemical and food industries, etc. The present invention relates to a dry granulation device comprising a combination of a roll-type compression molding device provided with a triangular prism-shaped ridge surrounding the ridge, a gear set coarse crushing 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.

FIG. 1 is an example of this, in which the powder 2 in the feed hopper 1 is transferred to the forming roll 4-a by a vertical screw 8.

4-b and compressed with the optimum pressure for molding the powder 2 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-integrated crushing device (composed 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 are obtained. Furthermore, a roll type crushing device commonly called a roll granulator, that is, a three-stage roller 9-1- whose cut section 2- has a vertical groove with a triangular cross section is used.
a, ot-b, 9-2-a, 9-2- b+ 9-8
-a, 9-8-b (Fig. 3 shows one stage of rollers, but the granules 10 are obtained by passing the granules through the groove pitch P of 1, for example, 3 mtrg, 2 m, and 111 m in order from the top of the three-stage roll). It will be done. Note that depending on the physical properties and the size of the required granules, two-stage rollers 9-1-
A, 9-1-b, 9-2-a, and 9-2-b may also take care of equipment.

Furthermore, since the granules 10 contain fine powder generated during coarse crushing or granulation, they are 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 mainly two possible reasons for this.

(2) The molding rolls 4-a and 4-b have the structure shown in FIG. 2, and the plate-shaped molded product 5 is easily susceptible to variations in molding pressure 8-force transmission and powder supply.

The center part is hard and both ends are soft. 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 that relies only on a method that generates a large number of fine powders, such as rubbing the crushed material against the punching plate 7 due to the impact of a rotor and the centrifugal force. ing.

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.

2.8 stages of rollers 9-1-a, 9-1-b.

As mentioned above, the granulator consisting of 9-2-a, 9-2-b, 9-3-a, and 9-8-b has a small groove pitch P of the triangular vertical grooves, and may be difficult to produce.

Since the groove spacing between opposing rollers is an important factor in granulation, high manufacturing precision is required.

Therefore, equipment costs are extremely high. On the other hand, during operation, powder adhesion occurs in the valleys of the vertical grooves, so in the current 4-way type, 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 one drawing.

FIG. 4 shows a royal elevational view of an improved forming roll of the roll-type compression molding apparatus of the present invention, and FIG. 5 shows a plan cross-sectional view of a molded product obtained by the roll of FIG. 4.

As shown in FIG. 4, in one embodiment of the present invention, a plurality of rows of triangular prism-shaped ridges surrounding the circumference are provided on the forming surface of one of the pair of rolls. It is effective for the protuberance to have an equilateral triangular shape or a shape close to it.

It is preferable that the intervals provided during roll forming are equal, and the pitch B of the protrusions varies depending on the size of the target granules, but when considering granulation in the pharmaceutical industry and manufacturing accuracy, it is approximately 1. ~Qsm [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 is obtained. In the case of the pitch B-4m carried out this time, T+ -1, 2m, T,
-0.8~0.411II11 The part corresponding to the protrusion becomes very thin, and when it is applied to the gear set coarse pulverizer shown in Figure 6 below, 76 parts are cut off by the shock, resulting in what is called ``Himokawa Udon''. Good coarse granules can be obtained by arranging and crushing noodle-like molded products.

Note that the cross section of the plate-shaped molded product shown in FIG. 5 has a noodle-like cross section that is substantially the same throughout.

Uniform molding can be achieved, and the drawbacks of the conventional dry granulation apparatus described above can be improved.

Figure 6 is a mechanical diagram of a gear set coarse crushing and granulating device in which two gears 18-a and 18-b are arranged in parallel, and the pitch k between the gear teeth of both gears is 1 of the thickness T of the plate-shaped molded product. It will be adjusted within the next few days. The gear teeth may have their peaks facing each other or may be offset like peaks and valleys, but it is particularly effective to combine the peaks.

Mechanically, this device uses shearing force, so generation of fine powder is extremely small.In addition, the scraping gear 14 with the same waveform is connected to gears 18-a and 18-b (in Fig. 6, gears 18-a and 18-b) (Only the 18-a side is shown.) By engaging the gears 18-a and 18-b, deposits on the gears 18-a and 18-b can be removed and stable coarse granules can be produced. However, gear 13-a
.

The scraping gear 18-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 arrow S using a known method such as a cylinder or cam mechanism.
It is arranged to periodically spread over the entire surface of the gear teeth of gears 18-a and 18-b. Also, gears 18-a, 18-
b and the gear teeth of the scraping gear 14 are as shown in Fig. 7 (
The shapes shown in (a) and (b) are considered, and particularly good results have been obtained with (b).

Preferred P1+θl + tl+P2 +θ2 and t
t is as shown in Table 1.

Table 1 Next, by using the improved forming roll shown in Figure 1 and the gear set coarse granulation device shown in Figure 6, the coarse granules become stable as described above, and as a result, the conventional 8-stage coarse granules are stabilized. Diagram 1 that was necessary
The granulator has two rolls 9-2-a, 9-2-b,
9-8-a.

9-8-'b or one stage roll 9- depending on powder physical properties
Equipment can be reduced to 8-a and 9-8-b.

Furthermore, depending on the size of the granules required, by installing the newly developed gear set coarse crushing and granulating device in two to eight stages, it is possible to obtain granules without using a conventional extremely 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-2 Further explanation will be added on how to scrape off the deposits.

The method for the gear set roll was explained in Fig. 6, but
As shown in FIGS. 8 and 9, for the vertically grooved roll shown in FIG. 1 used as a conventional granulator, a scraper with 9-notches 17 in the same gear teeth as the vertically grooved gear teeth is used. By meshing the vertical gear rolls 16 for removal (an appropriate clearance may be maintained in consideration of wear of the gear teeth and notches of both rolls), it becomes possible to scrape off deposits. 1. Although only the vertical gear roll 16 for scraping with respect to roll 9-1-a is depicted in FIGS. 8 and 9, roll 9-1-b
The same applies to Furthermore, the roll 9-2-a in FIG.
There is no need to explain that the same applies to 9-2-b, 9-8-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 the drawing]

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. FIG. 8 is a plan elevation view showing one stage of fluted rolls of a roll granulator. FIG. 4 is a plan elevation view of an improved forming roll according to the present invention. 1 figure 5
1 is a plan cross-sectional view of a molded product obtained by the improved forming roll shown in FIG. FIG. 8 is a perspective view showing the mechanism of the gear device for scraping the vertically grooved roll, and FIG. 9 is a plan sectional view showing a portion of FIG. 8. 11--2(

Claims (1)

[Claims] 1. A roll-type compression molding device, a gear-set 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 coarse crushing and granulation device. 8. A gear-set coarse crushing and granulating device that incorporates a deposit removal gear that can reciprocate from side to side in the gear groove. 4. Roll granulator-0 that incorporates a gear for removing deposits in the groove of the vertically grooved roll