JPH0632205Y2 - Nozzle tip for high viscosity coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a nozzle tip attached to a sleeve tip in order to prevent clogging by a coating agent in a spray nozzle for coating a tablet with a film base material.

(Prior Art) Some conventional spray nozzles have a cylindrical body (61) extending from the tip of a nozzle sleeve (60) as shown in FIG.

(Problems to be solved by the invention) However, in the conventional nozzle, since the cylindrical body (61) is formed of the same stainless steel material as the nozzle sleeve (60), when a highly viscous coating agent is sprayed, As shown in FIG. 11, agglomerates of the coating agent may adhere to the tip of the cylindrical body (61) and cause blockage (62).

In particular, an acrylic resin used as a film base material when coating an enteric-coated preparation tends to form an aggregate during spraying, which often hinders coating, and in some cases clogs the nozzle tip. There are times.

When this acrylic resin is sprayed using a conventional nozzle, aggregates with a length of about 3 mm are formed into a cylindrical body (6
1) Formed at the tip, there were problems that the amount of spray liquid fluctuated and the spray pattern was disturbed.

Therefore, it is necessary to monitor the coating condition,
It is an obstacle to unmanned process.

(Means for Solving the Problem) Therefore, a nozzle tip for coating a high-viscosity agent, which is disposed at the tip of the nozzle sleeve and is composed of a cylindrical body made of a material having excellent releasability, was devised.

That is, in a nozzle for coating a tablet with a film base material, a nozzle cylinder body formed of a material having excellent releasability composed of tetrafluoroethylene resin and opened and closed by a needle valve is provided at the tip of the nozzle sleeve. A nozzle tip for coating high-viscosity material, in which the outer peripheral surface of the body is tapered toward the tip and the inner peripheral surface is tapered toward the tip toward the tip. The taper angle is 10 to 20 °, and the reverse taper angle of the inner peripheral surface is 50 to 60 °.

(Operation) According to the present invention, by using the nozzle tip made of tetrafluoroethylene resin and having excellent releasability, the coating agent agglomerate does not adhere to the tip of the tip and the nozzle tip is clogged for coating. There is no obstacle.

Therefore, it is not necessary to monitor the coating state, and the process can be unmanned.

Further, at the tip of the tip, the outer peripheral surface is formed in a tapered shape toward the tip, and the inner peripheral surface is formed in a divergent inverse taper shape toward the tip, so that the coating agent is well diffused. Adhesion of aggregates can be prevented more effectively.

Further, the non-fine taper angle of the outer peripheral surface is optimally about 10 to 20 °, and the divergent taper angle of the inner peripheral surface is 5 °.
The most suitable range is 0 to 60 °.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

First, a system for coating a tablet with a film substrate will be described with reference to FIG.

In FIG. 8, (1) is a coating device,
A coating pan (2) is rotatable in the coating device (1) and is rotated by a motor (not shown). (A) is a tablet coated in the coating pan (2).

Inside the coating pan (2), the nozzle (3)
Is provided.

(4) is a liquid feed pump, and this liquid feed pump (4) always operates during the operation of the coating apparatus (1), and the coating agent (f) in the tank (5) is fed by the liquid feed pipe (6). Is constantly supplied to the nozzle (3) via the. A drain pipe (7) is a route for reducing the excess coating agent (f) or draining the cleaning liquid when it is not sprayed from the nozzle (3).

(10) is a working air control valve, and by opening this working air control valve (10), a working air supply pipe (11)
Air can be supplied through the needle to activate the needle valve (40) shown in FIG. 3 of the supply nozzle (3). When the operating air control valve (10) is opened, the needle valve (40) is opened and the coating agent (f) is sprayed from the nozzle (3). On the contrary, the operating air control valve (10).
Spraying is stopped when is closed.

Reference numeral (12) is a spray air control valve, and the spray air supply valve (13) is opened by opening the spray air control valve (12).
Air can be ejected from the tip of the nozzle (3) via the.

Reference numeral (14) is an air supply fan, which is constantly heated in the coating pan (2) via an air conditioner (16), a heat exchanger (17), and a filter (18) connected by an air supply duct (15). And the coated tablets (A) are dried.

(20) is an exhaust fan, and an exhaust duct (21),
The coating pan (2) is evacuated through the dust collector (22).

In the system as described above, the uncoated tablets (A) are carried into the coating pan (2), and the coating pan (2) is rotated in the arrow direction.

The operating air control valve (10) is opened while rotating, and the coating agent (f) is ejected from the nozzle (3). At this time,
At the same time, the atomizing air control valve (12) is opened, and air is ejected from the tip of the nozzle (3) to atomize the coating agent (f).

The atomized coating agent (f) is uniformly attached to the tablets (A) by the rotation of the coating pan (2).

When the tablets (A) in the pan are evenly coated,
The working air control valve (10) and the atomizing air control valve (12) are closed and the atomization is stopped.

Then, the coating pan (2) is continuously rotated for a while, and when the surface of the tablet (A) is dried, the rotation is stopped and the coated tablet (A) is removed from the inside of the coating pan (2).
And the coating is completed.

However, in the above coating process, when a highly viscous coating agent is sprayed, agglomerates of the coating agent (f) adhere to the tip of the nozzle (3),
May cause blockage.

Especially, the inside of the coating pan (2) has an air supply fan (14).
When the tablet (A) is an enteric-coated preparation or the like, a highly viscous acrylic resin or the like is used as the coating agent (f) because the heated air supplied by Aggregates of (f) are likely to be generated, which often adhere to the tip of the nozzle (3) and hinder the coating.

In order to solve the above technical problems, the present invention is provided at the tip of the sleeve that constitutes the nozzle (3), and is formed of a material that is made of tetrafluoroethylene resin and has excellent releasability. In addition, a nozzle tip for coating a high-viscosity agent, which is composed of a specially shaped cylindrical body, is devised.

Hereinafter, the nozzle tip for coating the high-viscosity agent of the present invention will be described.

First, the nozzle (3) will be described.

Figures 1 and 2 show a nozzle (3),
0) is a spray air supply port, (31) is a liquid supply port, (32)
Is a liquid discharge port, and (33) is a working air supply port.

Besides, (34) is a mounting metal for fixing the nozzle (3).

As shown in FIG. 3, the nozzle (3) includes a nozzle body (36), a cap (37) screwed to the tip thereof,
A cylinder cap (38) screwed to the rear end and a nozzle sleeve (3) screwed in the nozzle body (36).
9) and the needle valve (4) that moves back and forth inside the nozzle body (36) and the nozzle sleeve (39).
0) and.

A piston (41) is attached to the needle valve (40), and a spring (42) arranged in the cylinder cap (38) presses the piston (41) from the rear surface, so that the needle valve tip ( 41 ') is always urged to close the tip of the nozzle (3).

Then, the gap (4
3) has a cave (4) extending from the working air supply port (33).
4) are in communication, and therefore the working air supply port (33)
By injecting air from above, the piston (41) is retracted against the spring (42), and the needle valve tip (4
1 ') can be retracted from the tip of the nozzle (3).

Next, as shown in FIG. 4, the liquid supply port (31) communicates with a liquid storage chamber (45) formed between the nozzle sleeve (39) and the nozzle body (36), and the liquid supply port (31)
The coating agent (f) sent from the liquid storage chamber (45), the nozzle sleeve (39) and the needle valve (4).
It enters into the gap with 0).

When air is not press-fitted into the working air supply port (33), the needle valve (40) pressed by the spring (42) blocks the tip of the nozzle sleeve (39) as described above. The agent (f) does not eject from the tip of the nozzle sleeve (39), flows into the liquid return chamber (46) behind the liquid storage chamber (45), and returns to the return hole (47).
It is designed to be discharged from the liquid discharge port (32) via the.

Next, in the liquid storage chamber (45), the needle valve (40)
When the needle valve (40) is pushed down by pressurizing air from the working air supply port (33), the plug (51) is attached to the plug (51) as shown in FIG.
1) The liquid return chamber (4) behind the liquid storage chamber (45)
6) is blocked to prevent the coating agent (f) from returning,
The coating agent (f) is ejected from the tip of the nozzle sleeve (39) opened by the retreat of the needle valve (40).

As shown in FIG. 6, air is sent from the atomizing air supply port (30) into the nozzle body (36), and a circular hole (3) is formed in the cap (37).
Air is ejected from between 7 ') and the nozzle sleeve (39) to atomize the coating agent (f) ejected from the tip of the sleeve (39) to the nozzle.

In the above-mentioned structure, the nozzle tip (50), which is a feature of the present invention, is arranged at the tip of the nozzle sleeve (39) as shown in FIGS.

The nozzle tip (50) is made of a material having excellent releasability so that the coating agent (f) does not adhere thereto, and is made of tetrafluoroethylene resin.

Further, as shown in FIG. 7, the nozzle tip (50) is
At the tip end, the outer peripheral surface (50 ') is formed in a taper shape that is not tapered toward the tip, for example, a taper shape of about 15 °, and the inner peripheral surface (50 ") is tapered toward the tip, such as a divergent taper. By forming the taper in a reverse taper shape of about 60 °, the releasability from the coating agent (f) is further improved.

That is, since the outer peripheral surface (50 ') is formed in a tapered shape toward the tip, when the coating agent is ejected from the inner hole (37') formed in the cap (37), the tapered surface is formed. Along the inner surface (50 ″) of the nozzle tip (50), and thus toward the center of the diffusion surface of the coating agent that is ejected in a wide range. This is because they are well diffused without aggregation.

In the present invention, the nozzle material in which the coating agent is hard to adhere is selected so as not to cause the film formation on the nozzle discharge port in the coating device. A possible material shape was devised.c A nozzle tip shape was devised by using the spray mechanism of the two-fluid nozzle spray pressure to minimize the chance of film formation. What has been done The above a to d are devised. For a and d, tetrafluoroethylene resin is used, and for b, the formed film is blown tangentially, so the tip of the nozzle outer peripheral surface is used. It is formed in a taper shape that is thin toward the end. For c, it prevents the coating liquid from staying at the nozzle tip. Made it more minimization of film generation opportunities through the effect toward the distal end of the nozzle periphery to achieve the a divergent tapered, in which so as make the spray pattern from the nozzle.

In the nozzle (3) configured as described above, the working air supply pipe (11) is connected to the working air supply port (33), and the liquid sending pipe (6) is connected to the liquid supply port (31). In addition, the drainage pipe (7) is connected to the liquid discharge port (32), the spray air supply pipe (13) is connected to the spray air supply port (30), and coating is performed by the system described above with reference to FIG. By doing so, even if the coating agent (f) having high viscosity is sprayed, the aggregate of the coating agent (f) at the tip of the nozzle tip (50) does not adhere.

Therefore, even if an acrylic resin is used as the film base material when coating the enteric preparation, the formation of aggregates can be effectively prevented.

The results of various experiments conducted to construct the present invention are shown below.

As shown in FIG. 9, a: inner diameter [mm] of nozzle tip (50) b: outer diameter [mm] of nozzle tip (50) c: inner diameter [mm] of circular hole (37 ′) d: outer peripheral surface of tip (50 ′) taper angle [°] e: the reverse taper angle [°] of the inner peripheral surface (50 ″) of the chip is set, and a large number of nozzles having a to e of various values are manufactured, and the respective nozzles are manufactured. In, the formation time of aggregates and the maximum length of aggregates were actually measured.

In addition, acrylic resin is used for the coating agent (f), and the liquid feeding amount is 64 to 74 (ml / min) and the liquid temperature is 15.15 to
The experiment was conducted under the conditions of 19.05 ° C., air supply temperature 53.7 to 55.05 ° C., and exhaust temperature 37.2 to 40.65 ° C.

As a result, a: about 1.8 [mm], b: about 3 [mm], c: about 5 [mm], d: 10 to 20 [°], e: 50 to 60 [°]. The production time of the aggregate was 8.5 hours, and the maximum length of the aggregate was 3 mm or less.

An experiment was also performed in which the length of the nozzle tip (50) was changed, but the result did not change.

In addition, a nozzle tip (50) was manufactured by making an impregnated carbon fiber in a tetrafluoroethylene resin, and an experiment was conducted. However, the exfoliation was better when not impregnated.

(Effect of the Invention) In any case as described above, the present invention has the following effects.

The formation of agglomerates was very slow and the products were small, so there was no need to monitor the coating status during working hours.

In addition, the heat insulation of the nozzle tip was improved, and it became difficult to promote the formation of aggregates even at a high air supply temperature.

The sealability was improved by the contact between the needle valve and the nozzle tip, and liquid leakage was eliminated.

[Brief description of drawings]

1 and 2 are a side view and a front view of the nozzle, FIG. 3 is a nozzle cross-sectional view of the WW plane of FIG. 2, FIG. 4 is a nozzle cross-sectional view of the XX plane of FIG. 2, and FIG. Fig. 2 Nozzle cross section of YY plane, Fig. 6 Nozzle cross section of ZZ plane of Fig. 2, Fig. 7 enlarged cross section of nozzle tip, Fig. 8 tablet coating system diagram, 9 is a sectional view of the nozzle tip, and FIGS. 10 and 11 are sectional views of the nozzle tip according to the prior art. f ... Coating agent 1 ... Coating device 3 ... Nozzle 30 ... Spraying air supply port 31 ... Liquid supply port 32 ... Liquid discharge port 33 ... Working air supply port 39 ... Nozzle sleeve 40 ... Needle valve 50 ... Nozzle tip

Claims (2)

[Scope of utility model registration request] 1. A nozzle for coating a tablet with a film base, comprising a nozzle cylinder body formed of a material having excellent releasability made of tetrafluoroethylene resin at the tip of the nozzle sleeve and opened and closed by a needle valve. A nozzle tip for coating a high-viscosity agent, which is provided, wherein the outer peripheral surface of the cylindrical body is formed in a taper shape that is not thin toward the tip and the inner peripheral surface is formed in a taper shape that is divergent toward the tip. 2. The nozzle tip for coating a high viscosity agent according to claim 1, wherein the taper angle of the outer peripheral surface is 10 to 20 ° and the reverse taper angle of the inner peripheral surface is 50 to 60 °.