JPS58126117A - Blister forming drum - Google Patents

Abstract

PURPOSE:To form uniformly the top thickness of blister without thickness dispersion by a method wherein a thermoplastic sheet is sucked through sheet inlet ports and heated when the sheet is stuck to the peripheral surface of a drum body. CONSTITUTION:A drum body 31 is made from material having a large heat conductivity and cooled by the water circulated in the drum. Multiple concave pockets 34 are arranged on the peripheral wall surface 31b of the drum body 31 in the circumferential and axial direction. Material of small heat conductivity forms the peripheral wall and bottom on each concave pocket 34, which has a slit inlet port. The thermoplastic sheet is heated as it is stuck to the peripheral wall surface 31b of the drum body 31 through the inlet ports. The thermoplastic sheet is stretched, heated only at points where blisters are formed and the remaining section continues to be cooled. Thus, blisters are formed uniformly without thickness dispersion.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a blister forming drum that forms blisters by suctioning a heated thermoplastic sheet, and particularly relates to a blister forming drum that forms blisters by sucking a heated thermoplastic sheet, and particularly relates to a blister forming drum that forms blisters by sucking a heated thermoplastic sheet. suction and bring it into close contact with the peripheral wall of the drum body,
To provide a drum for forming blister blister using a polypropylene sheet, capable of forming blisters without variation by heating only the necessary parts.

First, a blister pack machine to which a blister forming drum according to the present invention is applied and a packaged product manufactured using the same will be explained. The packaging product 1 is generally used as a small packaging form for pharmaceutical tablets or capsules.
As shown in the first round and (B), the tablets are placed in a blister 3 formed on a vinyl chloride sheet 2 according to the size and shape of the tablets, aluminum foil 4 is thermally bonded to the bottom surface, and perforations are made for separation and cutting. 5 is arranged in a grid pattern.

This packaged product 1 is manufactured by a Pristapack machine 6 whose schematic configuration is shown in FIG. A thermoplastic vinyl chloride sheet 7 is unrolled from a reel 8, and is first vertically perforated in the longitudinal direction between a vertically perforated roll 9 and a roll 10 in contact with it, and then horizontally perforated. 1
1 allows horizontal perforations to be made in a direction perpendicular to the longitudinal direction. Subsequently, the sheet 7 is formed by arranging a plurality of concave pristers on a curved surface, and rotates in the direction of arrow A at a speed corresponding to the traveling speed of the sheet 7.
At this time, the drum 12 is heated by a heater 13 provided opposite to the circumferential surface of the drum 12 . The sheet 7 is sufficiently heated by the heater 13 and the suction operation is completed at a position B before it leaves the drum 12, and the sheet 7 is suctioned into the concave pocket and a blister is vacuum-formed. The sheet 7 becomes a blister-formed sheet 7a.

Next, tablets or capsules are automatically supplied one by one from the hopper 14 to the formed blisters by the supply roller 15, and the blister-formed sheet 7a further travels to reach between a pair of seal rollers 16 and 17.

On the other hand, the aluminum foil 18 is checked for printing pitch by a phototube 19, and is pulled out from the reel 21 while the feed amount is adjusted by the operation of the braking device 2o.
is thermally bonded to.

The formed blister is filled with tablets, etc., and aluminum foil 18
The sheet that has been thermally bonded to the back side is heated using tension roller 2.
A constant tension is applied by feed roller 23.
24, and the punching trimming mechanism 251
The product is then punched out and transported by a conveyor 26 as a packaged product shown in FIG. The punched waste is taken up by the take-up reel 2.
It is wound and arranged by 7.

Regarding the quality of the above-mentioned pharmaceutical packaging product 1, firstly, it is required to have sufficient moisture resistance. Generally, a vinyl chloride sheet is used as the sheet 7 because of its good moldability as described above. On the other hand, a polypropylene sheet is a thermoplastic resin sheet that is significantly superior to vinyl chloride in terms of moisture resistance. This polypropylene sheet is cheaper than vinyl chloride sheets, and is desired to be used as a substitute for vinyl chloride sheets.

However, polypropylene sheets have poor moldability, and when conventional drums are used, the thickness of the top of the blister becomes thin, and in some cases, holes may be formed at the top of the blister during molding. The portion of the sheet that was not formed became wavy and wrinkled due to the effects of heating, causing poor adhesion to the aluminum foil and causing the sheet to fail the moisture-proof pinhole test, making it impossible to use the polypropylene sheet in practice.

Therefore, the present invention relates to a blister forming drum that can form blisters with good stability so that not only vinyl chloride sheets but also polypropylene sheets can be used.One embodiment of the drum will be explained in detail below. .

FIG. 3 shows a blister forming drum according to the present invention. The blister forming drum 30 consists of a drum body 31 and side plate members 32. The drum main body 31 and the side plate member 32 are supported on a shaft 33 in a system in which the side end surfaces 31a and 321 are brought into contact with each other. The upper plate member 32 is fixed so as not to rotate, and the drum main body 31 rotates while the side end surface 31a is in sliding contact.

The drum body 31 is made of a material with high thermal conductivity, such as aluminum, and is cooled by circulating water inside. Further, on the peripheral wall surface 31b of the drum body 31, as shown in FIGS. 4 and 5 (A) and (B), a plurality of concave pockets 34 are arranged in the circumferential direction and the axial direction. It is a provision. This concave pocket 34 is made of a material having low thermal conductivity, such as polyimide resin, for the peripheral wall portion 35a and the bottom portion 35.
b, and has a structure having slit-shaped suction ports 36a to 36d. Each concave pocket 34 has suction ports 36a to 3.
6d and communicates with the axial suction path 37 of the drum body 31. The suction passages 37 are arranged along a circle with a radius R1, one for each group of concave pockets aligned in the axial direction.

Reference numeral 38 denotes suction holes which are an important part of the present invention, and are arranged in the drum axial direction between adjacent axially aligned concave pocket groups, and communicate with the suction passage 39 in the drum body 31. There is. The suction passages 39 are arranged one by one for each suction hole group aligned in the axial direction along a circle with a radius R2 ("%R1,>R1). 40 is a suction groove, and a predetermined suction hole 38
The grooves are formed on the surface of the drum body so as to enter into the openings of adjacent concave pockets of each group of concave pockets aligned in the axial direction of the drum.

Each suction passage 37, 38 is connected to the side end surface 31 of the drum body 31.
It opens at a.

Further, on the side end surface 32a of the side plate member 32, a first arcuate groove 41 and a second arcuate groove 42 are formed at the position of the radius R8, and a third arcuate groove 43 is formed at the position of the radius R2. be.

The first groove 41 is formed at position B, and the pipe 44
It is in communication with a suction pump 45 for completely forming the blister through it. The second and third grooves 42 and 43 are formed at positions preceding the first groove 41 in the rotational direction of the drum body 31 over a predetermined angle. In particular, -43 of the third groove is formed over an angular range (position B-0) corresponding to the heater 13 in FIG. -E). Second groove 4
2 is a suction pump 47 for forming a blister half through a pipe 46
It is a communication. The third #lI 43 communicates with a sheet adsorption suction pump 49 through a pipe 48.

Next, the operation when the blister forming drum 30 having the above structure is assembled in place of the drum 12 shown in FIG. 2 and forming a blister using a polypropylene sheet as the thermoplastic sheet will be described.

Depending on the speed at which the polypropylene sheet 50 is pulled out from the reel 8, the drum body 31 rotates in the direction indicated by the arrow. The sheet 50 is the drum body 3 in the aspect of the drum body 31.
Moves in unison with 1. Now, in the section of the drum body 31 that faces the heater 13 (the section between positions C and B), the suction path 39 faces the third arcuate groove 43, and the suction Air is sucked by the pump 49 through the suction hole 38 and suction #40, and the sheet 50 is attracted onto the peripheral wall surface 31b of the drum body 31'. That is, the sheet 50 is in close contact with the peripheral wall surface 31b of the drum body due to its own tension and the suction action, and when it moves to a location facing the heater 13, it does not rise above the peripheral wall surface 31b. It is maintained in close contact with the peripheral wall surface 31b.

Therefore, while the sheet 50 is heated by the heater 13,
When moving, the portions of the sheet 50 other than those facing the concave pockets 34, that is, the portions forming a grid pattern as a whole, are heated by the heater 13, but are removed by the water-cooled drum body 31 and are not heated at all. It is kept uniformly cooled without being heated, and the only part that is heated is the part that supports and opposes the concave pocket 34, that is, the part that is stretched to form a blister.

Therefore, in the blister-formed polypropylene sheet 50a that has passed through the portion facing the heater 13 and left the drum body 31, the grid-patterned sheet portion where no blisters are formed remains unaffected by heating and remains flat. Therefore, there are no wrinkles like in the conventional method. Therefore, the sheet 50a and Al [18 are thermally bonded well, no defective adhesion occurs, and the packaged product has excellent moisture resistance.

Note that the suction hole 38 is a small hole with a diameter of 0.7 cm, and the sheet is not sucked into the mosquito attraction hole 38, so that no protrusion is formed.

In addition, when the sheet 50 is in contact with the peripheral wall surface of the drum body only by the action of its own tension as in the conventional case, the sheet 50 is in a state of being in complete contact with the wall surface of the drum storage body F-J. This is difficult, and during movement, the sheet 50 repeatedly lifts up, albeit slightly, from the peripheral wall surface of the drum body, and then comes into close contact with it. If the sheet 50 floats even slightly, the sheet 50 will be heated and its temperature will rise. For this reason, the portion of the sheet that would normally be heated is heated and cooled repeatedly during the movement of the portion facing the heater 13, resulting in undulating wrinkles. But 1. According to the invention, the sheet portion that should not be heated is located at position 0-
In section B, as described above, the drum body is in close contact with the peripheral wall surface of the drum body and is not actually heated but is maintained in a cooled state, so that no wrinkles occur and the drum body is kept in its original flat state.

Further, while the sheet 50 moves from position 11D to position E, the blister is suctioned and gradually formed into a semi-formed state, and at position E, it is strongly suctioned and molded into a complete shape. FIG. 6 shows a molded pristar 51. Here,
Since the sheet that is sucked and expanded to form a blister is only the portion facing each concave pocket 34, each blister 51 is formed with no variation in thickness at the top, and the thickness etc. are constant. Become something. At this point, the sheet comes into contact with the inner wall surface of the concave pocket 34 during blister forming, but since the concave pocket 34 has a peripheral wall 35m and a bottom 35b made of polyimide resin, the heated sheet 50 Even when it comes into contact with the surfaces of the peripheral wall portion 35a and the bottom portion 35b, it is not cooled and remains heated. That is, the sheet during blister formation is kept in a heated state even during the blister formation, and the heated portion expands in a concave manner to form a blister, so that a blister with a thick concave portion is obtained.

Thereby, using polypropylene sheet as the thermoplastic rate, the packaging product 1 shown in FIG. 1 (5), (B)
can be realized.

Of course, it is also possible to use a general vinyl chloride sheet for the blister forming drum 30, and in this case, the blisters can be formed more uniformly and with less variation than in the past, and in some cases, It becomes possible to use a thinner sheet than the sheet, and it is possible to reduce material costs.

As described above, the blister forming drum according to the present invention has a plurality of concave pockets on its curved surface, and sucks the heated thermoplastic sheet that is transferred in contact with the curved surface and absorbs the thermoplastic sheet according to the shape of the concave pockets. In a blister forming drum for continuously forming blisters, the drum body is made of a material with high thermal conductivity, and a plurality of sheet suction holes are provided between the concave pockets, and the drum body is made of a material with high thermal conductivity. Since the thermoplastic sheet is heated using the sheet suction holes and is heated while being in close contact with the surface of the drum body, the thermoplastic sheet is heated only at the part where it is stretched and the blister is formed, and the other parts are heated. The part is kept in a cooled state without being heated during the process, and therefore, even if a polypropylene sheet with poor moldability is used, the sheet part that stretches to form a blister is the same for each blister. ．． As a result, the blister can be formed uniformly without any unevenness in the top thickness, and the rest of the sheet is kept cool, unaffected by heating, and returned to its original flat state without wrinkles. It is possible to obtain packaging products with excellent moisture resistance using polypropylene sheets, with no loss of adhesion with aluminum foil, and when using vinyl chloride J receipt, it is thinner than conventional sheets. Even if a sheet is used, it is possible to form a blister well, and it has a length that allows a thin sheet to be used and to reduce material purchasing costs.

[Brief explanation of the drawing]

Figures 1 (A) and (5) are respectively a plan view and a side view of an example of a packaged product, and Figure 2 schematically shows the overall configuration of a blister pack machine to which the blister forming drum of the present invention can be applied. FIG. 3 is a perspective view showing an embodiment of the blister forming drum according to the present invention broken down into a drum body and a side plate member, and FIG. 4 shows a part of the drum body in FIG. 3. 5(5) and (5) are a plan view showing the - concave pocket of the drum in FIG. 43 and a sectional view taken along the VB-VB line, and FIG. ] is a perspective view of a blister formed by concave pockets. 300. Blister forming drum, 31... Drum body, 31b... #Wall surface, 32... Side plate member, 33.
-e axis, 34... concave l kerato, 35a... circumference 1!
IIS 135b e *-bottom, 36a-36d*
ss slit-shaped suction port, 37.39---suction path, 38
s 38a """Suction hole, 40...Suction groove,
41, 42, 43...1 circular arc groove, 44, 46.48...
...Piping, 45°47.49...Suction pump, 50.
...Polypropylene sheet, 51...Blister. Figure 5 (A) 抛 (B) 4 Figure 6 Violet

Claims (1)

[Claims] A blister forming drum that has a plurality of concave pockets on its curved surface and sucks a heated thermoplastic sheet that is transferred in contact with the curved surface and continuously forms blisters according to the shape of the concave pockets, A plurality of sheet suction holes are provided in the drum main body made of a large heat-conducting material so as to open between the recessed pockets, and the thermoplastic sheet is sucked using the sheet suction holes to form the drum body. A blister forming drum characterized by being heated while being in close contact with the surface of the main body.