JPS6045353A - Film molding apparatus for ptp - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a film forming apparatus for FTP, particularly a drum-type forming apparatus for forming pockets for accommodating tablets or capsules in a polyvinyl chloride film by vacuum forming means. Regarding improvements.

As is well known, FTP, especially press-through-p packaging using polyvinyl chloride film,
ack) is a packaging form that is extremely widespread today as a simple packaging form for pharmaceutical tablets and capsules.

Packaging methods that have been widely used in the past for the purpose of continuous mass production of packaging bodies use a molding drum whose surface has been subjected to mold release treatment (for example, fluororesin treatment), and is continuously fed. By suctioning the thermally softened film from the inside of the drum, no engravings or crevices are formed on the drum.
This product naturally has an inner shape corresponding to the outer shape of the pocket to be shaped), and a pocket having an outer shape along the cavity surface is formed, and then desired tablets, etc. are filled one by one into the bottom of this pocket. After that, the opening is further sealed with aluminum foil laminate, and finally the package is punched out into a certain shape.

According to the second method, the packaging line can be moved virtually continuously and at a constant speed from forming pockets on the film to final dollying, which not only simplifies the conveyance mechanism. It has the advantage that it requires less maintenance and management effort. However, on the other hand, when using the drum L and the molding device, there is a drawback that the thickness of the shaped pocket bottom becomes extremely thin. That is, in the case of a normally used film having a thickness of about 300 mm, the thickness of the side wall and bottom of the pocket, especially the thickness of the corner portion, becomes as thin as approximately 40 mm or less. However, since polyvinyl chloride film, which is often used for this purpose, is not a material with particularly good barrier properties against water vapor permeation, it is inevitable that this thin bottom portion becomes a weak point against water vapor permeation. Therefore, the FTP shaped by this drum forming method cannot guarantee a sufficient shelf life unless it is further packaged with a material having excellent gas permeability resistance such as polyvinylidene chloride film or aluminum foil.

It is technically possible to overcome the above-mentioned drawbacks of the continuous forming means using a rotating suction drum by applying known sheet forming means such as pneumatic forming and plug assist forming. In fact, the deep drawing technology used in plastic cups and the like is actually far incomparable to the drawing level in FTP. However, the adoption of such measures necessarily
Significantly reduces the flow rate of the production line in the production of 'P. In addition, if such a deep drawing process exists in the middle of a line, a complicated adjustment mechanism will be required to adjust the speed difference between the speeds of the front and rear lines, resulting in a large increase in equipment costs and maintenance and management. Unable to avoid disadvantage. The present invention relates to a simple and effective means that can substantially solve the problems in the rotary drum type molding means described above.

The gist of the present invention resides in providing pressurized gas injection means directed toward the axial direction of the tram close to the outer surface of the FTP forming drum on the forming side adjacent to the heating roll. The attached Figure 1 schematically shows the second concept, and its feature is that pressurized air is injected toward the axial direction of the drum on the outer surface of the forming drum adjacent to the heating roll. The problem lies in the fact that the means have been established.

In the drawing, the molding equipment @ (I) is the upper molding drum (
2], a heating roll (3) located slightly away from and below the drum, a small presser roll f4 located on the side of the roll [3], and a side surface of the drum [2].
The nostle [61] that opens toward the axis (1) of the wooden tram (2) is installed in the air pipe (15).

A large number of grooves (7, 7) are formed on the circumferential surface of the drum (2).
...-) are bored radially, and the bottom of each of these recesses has small openings (=small intake holes, 8a, 8a・φ・) that are connected to the suction passage (8) inside the drum. Mark.

Note: In the actual molding drum, vacuum air channels and suction rings for connecting the channels with external vacuum sources, etc.
Since it requires a complicated configuration or is unrelated to the configuration of the present invention, it will be omitted in the main text. For details, please refer to the publicly known capital 4, for example, Japanese Utility Model Application Publication No. 149021/1983 filed by the applicant of the present application.

In known devices of this kind, the film (F) is fed by a separate feed roller (not shown) to the heated roll [3] and pressed tightly against the barrel surface of said roll [3] by a presser roll (4). After being heated and softened for about half a week, the roll is fed to the next forming drum [2]. As mentioned above, a large number of recesses (7) are carved on the circumferential surface of this drum (2), and a suction passage f8) is opened at the bottom of each of these recesses, and the softened film (F) is Since suction is performed as soon as the upper surface of the recess is reached, a pocket (P) corresponding to the inner shape of the recess is formed in the film (F). However, as mentioned above, since this suction is performed to forcibly stretch the film against the wall of the recess, only a pocket having an extremely thin bottom compared to the thickness of the film CF) is obtained. However, in the device of the present invention, pressurized gas is ejected from the nozzle (6) in response to the suction action from inside the drum, so the same action as when T-degree compressed air molding is used together is performed. As a result, when the film thickness is 300 pL, the thickness at the bottom, especially at the corners, increases to 70 to 80 squares or more. That is, the thickness of this bottom portion is twice or more than that without the gas injection means, and the effect brought about by this is obvious. In addition, the gas (usually clean air) injected here rapidly hardens the surface of the softened film (F) that has just been shaped, increasing the hardness of the film. Not only that, but also the transparency is improved. Furthermore, since the overall cooling rate is increased, the peripheral speed of the forming roll can be increased compared to the conventional method. As described above, although the device of the present invention is very simple, its effects are extremely large.

FIG. 2 shows a more concrete example of an apparatus to which the above-described inventive principle is applied. The air pipe (5) is arranged close to the heating roll (3) and parallel to the rotation axis (9) of the forming drum (2).One end of the upper air pipe +51
Accumulator 1111 via synchronous valve (10)
The accumulator is further connected to the compressor 1 via an air filter U21.

The above synchronization/help 110) is adjusted to control the flow of high-pressure air to the air pipe 15) at intervals according to the rotation angle of the forming drum [2], and the center and axis of each recess are For a certain period of time centered on the time when the line connecting the center (A) and the direction of each nozzle coincide, that is, while suction is being performed on the softened film (F), the direction of the axis of the drum (2) The opposite side shoots air. As a result, the film (F) is subjected to a pulling and suppressing action from both sides toward the inner wall of the recess [7]. Note that the number f14 in the figure is a shielding plate that prevents the jet air from hitting the heating roll.

Although it is difficult to understand why the difference in wall pressure of the shaped film decreases due to the air injection described below,
Probably, as a result of both suppression and suction occurring simultaneously, the forming speed is naturally faster than when only suction is used, and the resin constituting the film (F) is still in the glass transition state. This is probably due to the fact that shaping is completed during this period. In any case, the results achieved by the inventors make an important contribution to the development of the FTP packaging field.

The embodiments of the invention have been described above, but as mentioned above, the gist of the present invention is that the FTP molding drum is located near the outside 1fii of the drum on the molding side adjacent to the heating roll.
Since the pressurized gas injection means is provided in the direction of the axis of the drum, it goes without saying that this concept can be modified to a certain extent within the range that can be realized.

[Brief explanation of drawings]

Fig. 1 is a schematic side view showing the principle of the device of the present invention;
The figure is a partially cutaway perspective view of a main part showing an embodiment of the device of the present invention. The meanings of the symbols in each figure are as follows: □ l・The molding apparatus of the present invention (whole), 2: Molding drum, 3: Heating roll, 4: Presser roll, 5: Air pipe, 6: Gas injection nozzle, 7 : Recess in 2, 8: Suction passage in 2 (8a:
8 opening), ' 9: 2 rotating shaft, 1O2 synchronous valve, 11 near accumulator, 12: air filter, 13: compressor, 14: shielding plate; A: 2 axis, F2 PTP film, P, blur, 1.
. Patent applicant: Maruho Automatic Machine Co., Ltd. Agent: Kiyoshi Kadowaki, patent attorney

Claims (1)

[Scope of Claims] [1] An FTP molding drum characterized in that the outer surface of the drum on the molding side adjacent to the heating roll is provided with pressurized gas injection means directed toward the axial direction of the drum.
film forming equipment. [2] The gas injection means is a large number of gas blowing ports arranged in parallel in the axial direction of the drum on the outer surface of the FTP forming drum on the forming side adjacent to the heating roll, 2. The device according to claim 1, wherein the blow-off ports are configured to face each recess of the forming drum and inject pressurized gas in the axial direction of the drum. (3) The injection of pressurized gas forms the opening surface of the nozzle)
- The device according to claim 1 or 2, wherein the device is adjusted to perform the process intermittently each time a pocket of the film to be formed reaches a line connecting the axis of the ram.