JPH0118346Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a blister forming drum that forms blisters by suctioning a heated thermoplastic sheet.

First, a blister packing machine to which the blister forming drum of the present invention is applied and a packaged product manufactured using the same will be explained. Packaging product 1
is generally used as a small packaging form for pharmaceutical tablets or capsules, and as shown in Fig. 1A and B, tablets are placed in a blister 3 formed on a vinyl chloride sheet 2 according to the size and shape of the tablet. An aluminum foil 4 is thermally bonded to the lower surface of the aluminum foil 4, and perforations 5 for separation and cutting are provided in a grid pattern.

This packaged product 1 is manufactured by a blister pack 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. 11 allows horizontal perforations to be made in a direction perpendicular to the longitudinal direction. Subsequently, the sheet 7 is attached to the peripheral surface of a blister forming drum 12, which is formed by aligning a plurality of concave blisters on the peripheral surface and rotates in the direction of arrow A at a speed corresponding to the traveling speed of the sheet 7, At this time, drum 1
It is heated by a heater 13 provided facing the circumferential surface of 2. After the sheet 7 is sufficiently heated by the heater 13, a suction operation is performed at a position B before it leaves the drum 12, and the sheet 7 is sucked into the concave pocket to form a blister under vacuum. sheet 7
becomes a blister-formed sheet 7a.

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

On the other hand, the aluminum foil 18 is checked for printing pitch by a phototube 19, is pulled out from the reel 21 while the feed amount is adjusted by the operation of the braking device 20, and is transferred to the blister-formed sheet 7a between the pair of seal rollers 16 and 17. is thermally bonded to.

The formed blister is filled with tablets, etc., and the aluminum foil 18 is thermally bonded to the sheet from the back side, and a tension roller 22 applies a certain tension to the sheet.
It is intermittently transferred by feed rollers 23 and 24,
It is punched out by the punching trimming mechanism 25, and the first
The packaged product shown in the figure is carried out by a conveyor 26. The punched waste is wound up and organized by a take-up reel 27.

BACKGROUND ART The blister forming drum 12 of the blister packing machine 6 described above is configured to perform a suction operation only at position B to form blisters in one step.

Problems that the invention aims to solve: As a result, the sheet stretches rapidly and strongly, and the formed blisters inevitably have a thinner top, and this top thickness tends to vary between blisters. This was not fully satisfactory for pharmaceutical packaging, which requires strict moisture resistance. In addition, as a thermoplastic sheet, it is desired to use a polypropylene sheet, which has much better moisture resistance than a vinyl chloride sheet and is also cheaper, but this polypropylene sheet has poor moldability, so When using a molded blister, the top of the molded blister became extremely thin and sometimes had holes, making it unusable.

Means to Solve the Problems Therefore, the present invention makes it possible to form blisters gradually, not all at once, so that it is possible to control blister formation, to form high-quality blisters, and to form them as thermoplastic sheets. A polypropylene sheet can also be used.

Embodiment FIG. 3 shows an embodiment of a blister forming drum according to the present invention. This blister forming drum 30
is configured to continuously perform suction for forming the blister half, and the drum body 31 and the side plate member 3
2 and more. The drum body 31 and the side plate member 32 are supported on a shaft 33 in a positional relationship such that their side end surfaces 31a and 32a abut each other. The side plate member 32 is fixed so as not to rotate, and the drum main body 31 rotates in accordance with the running of the sheet attached to the peripheral wall surface 31b.

The drum body 31 is made of a material with high thermal conductivity, such as aluminum, and is cooled by circulating water inside. The peripheral wall surface 31 of this drum body 31
B is provided with a plurality of concave pockets 34 and suction holes 35, as shown in FIGS. 4 and 5A and 5B.

The concave pockets 34 are arranged circumferentially and axially. The concave pocket 34 is made of a material having low thermal conductivity, such as polyimide resin, for forming an opening peripheral portion 36a, a peripheral wall portion 36b, and a bottom portion 36c, and has slit-shaped suction ports 37a to 37d. As shown in FIG.
Cut out notches 40a~ from all sides with metal saw 39.
40d is press-fitted into the stepped hole 41 of the drum body 31 with the cut side facing downward, and a recess of a predetermined shape is bored in this small piece. Further, each concave pocket 34 has suction ports 37a to 37a.
It communicates with the suction path 42 through 37d. The suction passage 42 extends in the axial direction of the drum body, and is provided for each group of concave pockets aligned in the axial direction, and the opening to the side end surface 31a is radial.
They are lined up along the R ₁ circle.

The suction hole 35 is a small hole with a diameter of 0.7 mm,
The concave pockets are aligned in the axial direction of the drum between adjacent axially aligned concave pocket groups, and communicate with the suction passage 43 within the drum body. One suction passage 43 is provided for each suction hole group aligned in the axial direction.
The openings to the side end surface 31a are arranged along a circle with a radius R ₂ (>R ₁ ). Further, suction grooves 44 are formed on the surface of the drum body, extending from predetermined suction holes 35a. The grooves 44 extend between adjacent concave pockets of each drum axially aligned concave pocket group.

Further, the side end surface 32a of the side plate member 32 has a radius
A first arcuate groove 45 and a second arcuate groove 46 are formed at the position _R1 , and a third arcuate groove 47 is formed at the position _R2 . The first groove 45 is formed at position B and communicates with a suction pump 49 for complete blister molding through a pipe 48. Third groove 47
is formed over an angular range (position B-C section) corresponding to the heater 13 in FIG.
It communicates with a sheet suction pump 51 through the suction pump 51 .

The second groove 46 is an important part of the present invention, and is located at a position preceding the first groove 45 in the rotational direction of the drum body and at an angle included within the extension range of the third groove 47. It is formed within the range (position DE section). This second groove 46 communicates with a suction pump 53 for forming a blister half through a pipe 52. The suction force of this suction pump 53 is set to an appropriate value smaller than the suction force of the above-mentioned suction pump 49.

Next, the blister forming drum 30 having the above structure is assembled in place of the drum 12 shown in FIG. 2, and the operation when forming a blister using a polypropylene sheet as the thermoplastic sheet is shown in FIG. 7A.
- E, FIG. 8, and FIG. 9 will be described together.

The polypropylene sheet 54 moves integrally with the drum body 31 around the drum body 31. In the section of the peripheral surface of the drum body that faces the heater 13 (position C-B section), the suction path 43 faces the third arcuate groove 47, and the suction pump 51 draws air through the suction hole 35 and the suction groove 44. is attracted,
The sheet 54 is attracted onto the peripheral wall surface 31b of the drum body 31. Therefore, when the sheet 54 moves through the heating section, only the portion facing the concave pocket 34 is heated, and the other portion that is in close contact with the cooled peripheral wall surface 31b of the drum body 31 is actually heated. It is said that the liquid remains cooled. Therefore, in the blister-formed sheet 54a, the sheet portion of the grid-like pattern in which the blister is not formed remains flat without being affected by heating, and no wavy wrinkles occur. Therefore, the sheet 54a and the aluminum foil 18 are thermally bonded well, and the bonded portion has excellent moisture resistance. In addition, in FIG. 8, L indicates a heating section.

When the sheet 54 in this partially heated state moves through the position DE section, which is the section before reaching position B, the suction path 42 faces the second arcuate groove 46,
The air inside the concave pocket 34 flows through the suction path 42 and the groove 46.
Through the suction pump 53, suction is performed with a relatively weak force. Further, the temperature of the sheet 54 is low at position C and increases as it moves to position B.
becomes easier to expand. Therefore, the heated sheet 54 is expanded and gradually drawn into the concave pocket 34, and blister forming progresses. That is,
In the position, the sheet 54 becomes a first stage semi-formed blister 55a which is slightly retracted into the concave pocket 34, as shown in FIG. 7A, and in the position, the sheet is further retracted, as shown in FIGS. 7B and C, respectively. The second-stage semi-formed blister 55b and the third-stage semi-formed blister 55c are shown in FIG. This becomes a semi-formed blister 55d. This semi-formed blister 55
The shape of d can be changed by changing the suction force by the suction pump 53.

When the sheet 54 reaches position B (position), the suction path 43 faces the first groove 45, and the air in the concave pocket 34 is suctioned with a strong force by the suction pump 49, and the sheet 54 is further The blister is expanded and drawn into the concave pocket 34, and is brought into close contact with the peripheral wall 36b and bottom 36c of the concave pocket 34 as shown in FIG. It will be done.

In FIG. 8, M indicates a suction section for half-forming, and N indicates a suction section for complete molding.

As mentioned above, since the blister 56 is formed from a flat sheet through the half-formed blister 55d, the rapidity of sheet expansion during blister forming is slow, and the suction force of the suction pump 53 for half-blister forming is slow. By setting it appropriately, it becomes possible to control the progress of blister forming, so that the blister 56 is formed under the best conditions. Also, when the blister half is formed, the sheet 54 comes into close contact with the inner surface of the concave pocket 34,
Since the concave pocket 34 is made of polyimide resin, which is a material with low thermal conductivity, the concave pocket 34
The portion of the sheet that is in close contact with the inner wall surface of the pocket is not immediately cooled due to the removal of heat, but is maintained in a heated state in the same way as the portion of the sheet that is away from the bottom surface of the pocket.
For this reason, when the forming of the semi-formed blister progresses, and from the semi-formed blister 55d, the blister 56
When molding, in addition to the sheet portion that is spaced apart from the pocket bottom surface, the sheet portion that is in close contact with the pocket peripheral wall portion 36b is also expanded. That is, the blister 56 is formed in the state shown in FIG. 7A by uniformly stretching the entire heated sheet portion, so that the thickness of the top portion does not decrease much compared to the thickness of the sheet material. Ru.

As a result, it is possible to form blisters well even on polypropylene sheets with poor formability, and even if a thinner vinyl chloride sheet than before is used as a vinyl chloride sheet, a blister with approximately the same thickness at the top as before can be formed. become. Therefore, polypropylene sheets can be used as thermoplastic sheets,
In addition, in the case of vinyl chloride sheets, thin vinyl chloride sheets can be used without any problems, and both material costs can be reduced, and especially in the former case, packaging products with excellent moisture resistance can be obtained. .

FIG. 10 shows another embodiment of the blister forming drum according to the present invention. This blister forming drum 60 has a structure in which suction for forming blister halves is performed intermittently with pauses, and has substantially the same structure as the drum 30 shown in FIG. 3. In FIG. 9, the same components as those shown in FIG. 3 are given the same reference numerals, and their explanations will be omitted. The drum body 31 of the drum 60 is exactly the same as the drum body 31 shown in FIG.
The side plate member 32 is the same as the side plate member 32 of FIG. 3 except that the number 6 is omitted and suction ports 61a to 61d are provided. The suction ports 61a, 61b, 61c, and 61d are located at predetermined pitches along an arc of radius _R1 at the above-mentioned positions.
, are placed at locations corresponding to . Each of the suction ports 61a to 61d communicates with a suction pump 53 for forming a blister half through piping 62a to 62d, respectively.

When this drum 60 is used, the relationship between sheet heating, half-forming of the blister, and complete molding is as shown in FIG. In the figure, the sheet heating section L and the blister complete forming section N are the same as in FIG. Regarding the blister half-forming section, suction for half-blister forming is performed only when the same suction path 42 faces each suction port 61a to 61d, and when the suction path 42 is located between each suction port. This is not performed when the side face 32a is facing the side end face 32a. That is, the suction for forming the blister half is performed intermittently with pauses in between, and as shown in FIGS.
As shown in D, the blister half-forming progresses. 1st
In Figure 1, M ₁ to _{M 4} indicate the blister half-forming section,
O ₁ to _{O 3} indicate pause sections.

In this way, performing the blister half-forming intermittently with a break in the middle is particularly effective when using a vinyl chloride sheet. That is, vinyl chloride sheets have a remarkable property of being restored when heated, so much so that when heat is applied to a formed blister, it returns to its original flat state. For this reason, due to the heating during the half-forming pause period, the semi-formed blister tends to return to its original flat state, and the thickness is restored as the thickness approaches the thinned portion. Therefore, thinning of the top of the blister is effectively prevented, and a blister having a sufficient thickness at the top can be formed.

The operation when completing the blister from the state shown in FIG. 7D and the effect of the concave pocket formed by embedding the polyimide resin are exactly the same as in the above case.

Effects of the Invention As described above, according to the blister forming drum of the present invention, the semi-formed blister is heated in the suction pause section without any suction force being applied, and the thermoplastic sheet is heated in the semi-formed state. For example, the thickness of the blister part can be effectively restored, the blister can be formed more easily than when suction is applied continuously, and the blister can be of stable quality. Blisters can be molded into polypropylene sheets, which could not be used in the past due to poor moldability, and when using vinyl chloride sheets, blisters can be molded into sheets that are even thinner than before. Further, since the drum body is composed of a drum body and a side plate member, the suction operation for half-blister forming can be performed stably, and the structure of the forming drum can be simplified.

[Brief explanation of drawings]

1A and 1B are a plan view and a side view of an example of a packaged product, respectively; FIG. 2 is a diagram schematically showing the overall configuration of a blister packing 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 of the present invention disassembled into the drum body and side plate members, FIG. 4 is a side view showing a part of the drum body in FIG. 3, and FIG. Figure 5A
and B are a plan view and a sectional view taken along the line VB-VB of the drum shown in FIG. 3, FIG. 6 is a diagram showing a method for manufacturing the recessed pocket shown in FIGS. Figures A to D are diagrams showing the state of the semi-formed blister at different stages of the blister semi-forming process;
Figure E shows the state when the blister is completely formed.
FIG. 8 is a diagram showing the heating section, half-blister forming section, and completely blister forming section in the drum in FIG. 3 in correspondence; FIG. 9 is an enlarged perspective view of the formed blister; and FIG. 10. 11 is a perspective view showing a blister forming drum according to another embodiment of the present invention, and FIG. 11 shows the heating section, half-blister forming section, pause section, and complete blister forming section of the drum in FIG. 10 in correspondence with each other. It is a diagram. 30, 60...Blister forming drum, 31...
...Drum body, 32, 32A...Side plate member, 33
... shaft, 34 ... concave pocket, 35 ... suction hole, 36a ... opening surrounding section, 36b ... peripheral wall section,
36c...bottom, 37a-37d...slit suction port, 42, 43...suction path, 44...suction groove, 45...first circular arc groove, 46...second circular arc groove, 47 ...Third arcuate groove, 49... Suction pump for complete blister formation, 51... Suction pump for sheet adsorption, 53... Suction pump for forming blister half, 54... Polypropylene sheet, 55a~
55d...Semi-formed blister, 56...Blister,
61a to 61d...suction ports.

Claims (1)

[Claims for Utility Model Registration] Having a plurality of concave pockets on the circumferential surface, and of the plurality of concave pockets, a plurality of concave pockets are provided in communication with each group of concave pockets arranged in the axial direction. a drum body whose other end has a plurality of suction passages opened circumferentially distributed on a side end surface, and which transports a thermoplastic sheet which is in a heated state and attached to the circumferential surface according to its rotation; The thermoplastic sheet is placed in contact with the side end surface of the drum body so as not to rotate, and the thermoplastic sheet is suctioned through the suction path and the concave pocket before reaching the blister forming point to semi-form the blister. A blister forming drum comprising a side plate member having a mechanism for intermittently suctioning between pause sections and a mechanism for suctioning to completely form the blister at the blister forming point.