JPS599343B2 - Method and apparatus for sealing inner seam edges of coated paper cups - Google Patents

Description

Detailed Description of the Invention The present invention involves rolling a flat half-finished piece into a cylindrical body, overlapping the seam edges, and applying a sealing material to the part that will become the inner seam edge before rolling the half-finished piece. The present invention relates to a method and apparatus for sealing the inner seam edge of a coated paper cup cylinder.

The cylindrical body of a paper cup is usually formed by rolling a flat blank piece and slightly overlapping the seams.

In this case, the half-finished piece is usually coated on one side with, for example, plastic, and the other side is coated because it is necessary to seal it to the outside because it stores liquid in a paper cup. One side will be the inside of the cup.

Disadvantages of cups made in this manner include an uncoated inner seam edge in the overlap area.

Through this uncoated inner seam edge, for example oils and fats can penetrate into the paper layer, deteriorating the performance of the paper cup over time and causing particularly unsightly discoloration.

Therefore, various methods of sealing this inner seam edge have been attempted.

First, attempts were made to apply glue to the cut edges (open ends) to seal them, but this method did not provide a satisfactory sealing effect and caused manufacturing difficulties as the glue adhered to the cup forming tool. It ended in a result.

Folding back the inner cup edge so that the inner seam edge also has a coating will also result in this area of the cup being thicker than other parts, making further processing difficult, such as rolling the mouth or bottom. Because of the difficulty, it has not been put to practical use.

The sealing effect of the cup material was also difficult because the materials were thick and overlapped.

Therefore, attempts were made to create a tapered shape on the inner seam edge to prevent the cup wall from becoming thick after folding.

However, even here, it was not possible to expect an absolutely reliable sealing effect, and seal 1 of the paper cup was only achieved by coating the inside with auxiliary plastic foil.

However, cups manufactured by this method are extremely expensive.

A sealing method is also known in which flat blank blanks are piled up and then a sealing material is manually applied to the area that will later become the inner seam edge of the cylinder.

The disadvantage of this method is that the sealant gets in between the stacked individual blanks, causing the sealing surfaces to adhere to each other, making subsequent sealing operations impossible or difficult. .

SUMMARY OF THE INVENTION It is therefore an object of the invention to provide a method in which the internal seam edges in question can be sealed by mechanical manipulation.

This objective can be achieved by aligning and fixing the individual blanks before applying a sealant.

In this case, it is sufficient to take out the semi-processed pieces one by one, separate them, adjust the orientation, and then bend them slightly.

That is, in this way, strength is imparted to the blank, while the sealant application member is brought closer to the edge of the blank without deforming the blank or using areas where the sealant should not be applied. This is because it is possible.

It is convenient because the sealing material does not invade the sealing surface, there is no fear that the sealing material will be applied over an unnecessarily wide area, and the liquid sealing material can be spot-coated and then dried.

A device that separates the blank pieces one by one and aligns them with a conveyance path, and at least one device that grips, fixes, and bends the blank pieces.
The method of the invention can be carried out in a very simple manner by using an apparatus comprising a pair of clamping jaws and a sealant applicator movable relative to the clamping jaws in contact with the side edges of the blank. Performed mechanically.

In a preferred embodiment, a small
In both cases, one spot coating strip is provided in the coating device.

In this way, the sealing material can be applied only to the side edges in the spot coating process, and the spot coating piece is made of a transparent and absorbent material and is filled with the sealing material under a certain amount of pressure. This can be done very easily by attaching it to one end of the conduit.

In particular, if the conduit is connected to a tank filled with sealing liquid and equipped with a liquid level control device and placed at least at the same height as the open end of the conduit, it is possible to coat the side edges of a large number of workpieces in sequence. can.

In this embodiment, the spot coating strip is located at one end of the communication tube, and the amount of liquid in which the spot coating strip is immersed can be controlled by a liquid level spool in the tank.

Correct positioning of the blank is a prerequisite in order to ensure that this spot application takes place precisely on the side edges only.

In order to separate the half-finished pieces one by one and arrange their positions, a known suction arm is provided to take out the half-finished pieces one by one from the stack of half-finished pieces and send them to a conveyance path, and the axis of the conveyance path is This can be achieved very easily by comprising a plurality of small support rollers that are moved obliquely, and by providing a lateral stop edge on the side of the conveyance path that corresponds to the direction of movement of these small support rollers.

With this configuration, the blanks on the conveying path are guided into abutment against the stop edge, so that a lateral force alignment takes place.

A stopper piece is provided in the vicinity of the clamp jaw to limit the movement of the blank piece on the conveyance path in the feeding direction, and after applying the sealant, pivots out of the area to enable the subsequent movement of the blank piece.

Preferably, the blanks are guided along the conveyance path by a movable feed plate that periodically operates in conjunction with the suction arm.

A preferred embodiment includes a rail-like lower clamping block disposed below the conveying path such that the clamping jaws are longitudinally aligned with the conveying path, and an upper clamping jaw descending from above to cooperate with the conveying path. Consists of.

The lower clamping block and the upper clamping jaw each have concave or convex surfaces in facing relation to each other, the length measured in the feed direction approximately matching the width of the blank extending in this direction. do.

In this way, the aligned and restrained blanks are held and slightly bent, which strengthens the paper, and the sealant is applied by abutting the spot coated strips against the side edges. There is no risk that the semi-finished piece will break or be damaged.

The spot-coated blanks can then be sent to a drying device.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

The first step is to stack a number of half-finished pieces 6, which are processed into a rounded cup cylinder as shown in Fig. 2 by overlapping both edges 2 and 3 over a certain width 4 and joining them together. This is a semi-processed paper stack 1 shown in the figure.

This processing operation can be carried out very easily if the plastic layer 5 provided on one side of the semi-finished paper piece 60 is heat-sealed to adhere the overlap area.

The individual blanks 6, shown by the rounded shapes 6a in FIG. If a liquid or a liquid substance is injected into the overlap area, it will invade the overlap area, and there will be a point inside the overlap area 4 (Fig. 3) where it will leak beyond this to the outside. cormorant.

Therefore, it was decided to provide a layer of sealing material 7 on this side edge 2 by the method of the present invention using the apparatus shown in FIG.

For this purpose, the semi-processed paper pieces are taken out one by one by a suction arm (not shown) from below the semi-processed paper pile 1, and
0 onto a feed roller 9 driven by 0 in the feed direction 8.

Behind the feed roller 9 is a feed plate 11 provided on a chain rotating between shafts 10 and 10a, for example.

The blank 6 from the feed roller 9 is captured by the feed plate 11 and advanced in the feed direction 8 .

In addition to the movable feed plate 11, a conveyance path 12 is constituted by a plurality of small support rollers 13 located on the same plane, and the semi-finished piece 6 is made to run on this conveyance path 12.

In the illustrated embodiment, the axis of the small support rollers is not perpendicular to the feeding direction 8, but is arranged at an angle such that the semi-finished piece 6 carried on the small support rollers 13 moves to the left on these small support rollers. be.

Since the surface of the small support roller is configured to contact the back side of the blank workpiece 6, the workpiece is guided to the left on the conveyance path 12 by the feed plate 11 until it collides with the stop edge 14. .

Once abutted, the blank is aligned in its lateral position and is further fed by the feed plate 11 to position 6b, where it reaches position 11a.

The half-finished piece 6 at this position 6b collides with the two restraining pieces 15, and at this moment the feeding operation of the feeding plate 11 ends.

The blank 6 in position 6b has a pair of clamping jaws 16 extending approximately along the feed direction 8 as schematically shown in the drawings.
and the lower clamp block 16a and upper clamp block 16a as shown in detail in FIGS. 5 and 6.
It is held between the jaws 16b.

The lower clamp block 16a has a concave notch 17,
The upper clamping jaws 16b each have a convex lower surface 18, so that the blank 6 in position 6b is given a slight curvature.

This curvature strengthens the paper blank itself and provides some resistance to mechanical contact.

This mechanical contact is effected by a spot application strip 19 of an absorbent and permeable material impregnated with a liquid sealant, as schematically shown in the drawings.

As is clear from FIG. 4, the spot application piece 19 is provided at one end of the conduit 20 whose other end opens into a tank 21, and the surface of the liquid sealing material 230 in the tank 21 is provided with the spot application piece 19. A liquid level control device is provided to control the liquid level to be at the same level as or higher than the end of the conduit 20 provided.

By controlling the liquid level of the sealing material 23 in the tank 21, the amount of sealing material absorbed by the absorbent spot application strip 19 can be controlled, as is clear from FIG.

Move this spot application piece 19 in the direction of arrow 24 and
It is brought into contact with the side edge 2 of the half-finished piece 6 at the position.

For this reason, the side edge 2 of the spot application piece 190 is fixed.
, and move it perpendicular to the side edge 2.

In this spot coating process, the side edges are wetted, and there is no need to provide a sealing material in the overlap area 4, thereby saving the effort.

Next, the stopper piece 15 is lowered, and the feed plate 11 at the position 11a is moved again to place the blank piece 6 at the position 6b on the feed roll 25, thereby sending the blank piece to the drying device 26. The workpiece occupies position 6C, where the side edges 2 are dried.

The blanks removed from the drying device 26 are sent to a known device for shaping them into the shape shown in FIG.

For example, as shown in FIG.
While the side edges of one blank are being coated with sealant at position 6b, the second blank is sent from feed roller 9 to a conveying path consisting of small support rollers 13, and so on. The times are set sequentially.

If the upper clamping jaw 16b and the lower clamping block 16a are provided with corrugated clamping surfaces 27 and 28 corresponding to each other as shown in FIG. Since it is not necessary to make the coated piece higher than a certain height, it is particularly useful for wide blank pieces.

Therefore, if this clamp is adopted, by controlling the liquid level of the sealing material in the spot coating device as described above, it is possible to supply the sealing material only above a certain height of the spot coating member. It's advantageous.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view showing an apparatus for carrying out the method of the present invention, and FIG. 2 is a perspective view showing a cylindrical body made from a blank piece cut as shown in FIG. FIG. 3 is an enlarged view showing the overlapping position of the side surface of the cup in FIG. 2 together with the edge seal formed by the device shown in FIG. 1, and FIG. 4 is a spot coating device provided for applying the sealing material. FIG. 5 shows an embodiment of a pair of clamping jaws for fixing a blank in the application position, and FIG. 6 shows another embodiment of a pair of clamping jaws. 1 is a stack of semi-processed paper pieces, 2 and 3 are side edges, 4 is an overlapping area, 5 is a plastic layer, 6 is a semi-processed piece, 7 is a sealing material, 9 is a feed roller, and 13 is a support roller. , 14 is a restraining edge,
15 is a stopper piece, 19 is a clamp jaw, 19 is a spot application piece, 23 is a liquid seal treatment material, 27. 28 each indicate a clamping surface.

Claims (1)

[Scope of Claims] 1 A flat half-finished piece is rolled into a cylindrical body, and the seam edges thereof are overlapped, and at this time, a sealing material is applied to the part that will become the inner seam edge before rolling the half-finished piece. This is a method of sealing the inner seam edge of a coated paper cup, which involves taking out the semi-finished pieces 6 one by one from the semi-finished piece pile 1, adjusting their position, bending them slightly at this position, and holding them. The half-finished piece 6 is fixed, and then,
A method for sealing the inner seam edge of a coated paper cup, characterized in that a sealing agent 23 is spot-coated in liquid form on the side edge 2 of a blank 6 and the sealing agent 23 is dried. 2. A coated paper cup in which a flat semi-finished piece is rolled into a cylindrical body, the seam edge of the cylinder is made to overlap, and a sealing material is applied to the part that will become the inner seam edge before rolling the semi-finished piece. a sealing device for the inner seam edge of the machine, which separates the blank pieces 6 one by one from the blank stack 1 and aligns them at a predetermined position on the conveyance path 120;
at least one pair of clamp jaws 16 for gripping, fixing, and bending the aligned blanks, and a clamp for contacting the side edges 2 of the blanks. and a spot application device for applying a sealing material 23 movably mounted on the jaws. 3. The apparatus according to claim 2, characterized in that the spot coating apparatus is provided with at least one spot coating piece 19 impregnated with a sealing material 23. 4. The spot application piece 19 is made of a transparent and absorbent material and is provided at one end of a conduit 20 filled with a sealing material 23 under pressure. The device described. 5 In order to separate the blank pieces 6 one by one and adjust their positions, a suction arm is included to take out the blank pieces 6 one by one from the blank stack 1 and send them to a conveyance path, and the conveyance path has an axis centered in the feed direction 8.
It includes a plurality of small support rollers 13 that are obliquely moved relative to each other.
4. The device according to claim 2, further comprising: 4. 6. The device according to claim 5, wherein all the small support rollers 13 are arranged so that their axes are parallel to each other. 1 When applying the sealant, the semi-finished piece 6 on the conveyance path 12
After stopping the movement in the feeding direction 8 and applying the sealant,
The clamping jaws 16 move the stop piece 15, which pivots out of the area, to allow the blank to move further in the feed direction.
7. The device according to claim 5 or 6, characterized in that the device is provided near the. 8 Periodically moves in the feed direction 8 together with the suction arm to move the semi-finished piece 6 along the conveyance path 12 to the sealing material application position, and when applying the sealing material, it is moved and blocked by the stopper piece 15 to seal the material. 8. The apparatus according to claim 7, further comprising a feed plate 11 for feeding the semi-finished piece in the feed direction 8 after coating the material so as to cooperate with the stopper piece 15. 9. A rail-shaped lower clamp block 16a arranged below the conveyor path 12 such that the clamp jaws 16 are aligned with the conveyor path 12 in the longitudinal direction, and an upper clamp block 16a lowered from above and cooperating therewith. 3. A device according to claim 2, characterized in that it comprises a jaw 16b. 10 The lower clamping block 16a and the upper clamping jaw 16b are each provided with mutually corresponding concave or protruding surfaces 17, 18 whose length, measured in the feed direction 8, approximately corresponds to the width of the blank 60 extending in this direction. 10. The device according to claim 9, characterized in that: 11 Mutually corresponding clamping surfaces 27.2 of the lower clamping block 16a and the upper clamping jaw 16b
11. The device according to claim 10, characterized in that 8 is formed in a wave shape.