JPH056105Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an apparatus for fusing and welding plastic films in an L-shaped sealer.

[Prior Art] In a conventional L-shaped sealer, such as that disclosed in Japanese Utility Model Application Publication No. 58-86316, the upper and lower films are separated by lowering the L-shaped sealer onto an L-shaped seal pedestal. is disconnected at the same time,
The cut edge was welded, and the seal pedestal was made of heat-resistant rubber or the like and had a flat top surface. Further, the L sealer had a cutting blade sandwiched and held between the left and right half members constituting the heat bar, and the cutting blade portion of the cutting blade was made to protrude from between the left and right half members.

When the L sealer is lowered, the cutting blade presses the upper and lower films against the sealing pedestal, cuts the film by biting into the pedestal, and at the same time, the left and right half members press the upper and lower films and weld them together. It was hot.

[Problems to be solved by the invention] However, according to the conventional fusing and welding device as described above, the cutting edge of the cutting blade is straight, so if the cutting edge is not good, the cutting ability by pressing will be poor. There is a problem in that operation troubles frequently occur due to the fact that the lower film is left uncut, and the upper and lower films must be cut in a two-stage operation.

Additionally, in order to avoid such inconveniences, heat wires were sometimes used to fuse the film, but there was a problem in that the heat wires would burn out during continuous operation, resulting in disconnection of the heat wires. .

Furthermore, as disclosed in, for example, Japanese Utility Model Application Publication No. 57-43130, a concave groove is formed to cross the film transport path, and a heated cutting blade is provided protruding from the center of the width of the seal bar. There is a synthetic resin film fusing device made of. However, even in this device, the cutting edge of the cutting blade is straight,
Moreover, like the device disclosed in the above-mentioned Japanese Utility Model Publication No. 58-86316, satisfactory results cannot be obtained by simply pushing the film, so the cutting blade is moved in the transverse direction of the film to perform the cutting. the result,
The structure of the sealer itself becomes complicated, leading to increased costs.

In view of the above-mentioned circumstances, this idea was developed by making the cutting blade not only have a cutting action due to its sharpness, but also an effective fusing action due to heat, so that it can cut the underlying film in one step. The object of the present invention is to provide a fusing and welding device that can cut all at once.

[Means for Solving the Problems] The configuration of this means for achieving the above object includes an L-shaped seal bar and a seal pedestal,
In a plastic film fusing and welding device that sequentially fuses and seals bi-folded films that are housed inside to be packaged and is supplied intermittently in an L-shape, a blade is installed at the center of the width of the seal bar from the sealing surface of the seal bar. The cutter blade has a protruding portion, and the blade portion is formed into a saw blade shape with sharp cutting edges arranged at equal intervals, and the seal holder has a similar blade on the surface of the holder opposite to the cutter blade. The gist is that a groove is formed that is large enough to loosely fit the cutter blade.

[Function] According to the above structure, the upper and lower films stretched over the groove are stopped by the film holder so that they do not shift, so the cutting edge of the cutting blade reliably penetrates the upper and lower films, and the cutting edge and the cutting edge are separated. Even if there is a part of the film that does not tear between the film and the film, it is susceptible to high heat, so the heat melts and contracts, causing the tear to expand.

[Example] Next, an example of this invention will be described based on the drawings.

FIG. 6 schematically shows a packaging machine for an L-type sealer, in which a film feeding device 4 from a roll film 3 is provided next to a belt conveyor 2 that supplies packaged articles a to a sealing device 1. 4
A film opening device 5 is provided in front of the camera.

The film opening device 5 consists of an upper guide plate 6 above the belt conveyor 2 and a lower guide plate 7 on the back side, and a pair of left and right support rods 8 and 9 that sandwich the belt conveyor 2 so that the article a can pass between them. Both guide plates 6 and 7 are integrally connected, and the entrance 10 for article a is
is opened obliquely on the opposite side of the feeding device 4.

That is, both guide plates 6 and 7 of the opening device 5 are both right-angled equilateral triangles of the same size, and the oblique sides facing the right angle portion 13 are positioned as the entrance edges 11 and 12 for the article a.

Then, while applying the upper piece f ₁ of the bifold film f unrolled from the roll film 3 to the upper surface of the upper guide plate 6, and inserting the lower piece f ₂ under the lower guide plate 7, Rim 11,
Fold it back at 12 and turn it inward to open the opening device 5.
At the entrance 10 of the film F, the film F is turned upside down and opened, and in this state it can be drawn out from the opening device 5 into the sealing device 1.

In the sealing device 1, an L sealer 15 is provided on a seal pedestal 14 so as to be openable and closable, and when the L sealer 15 is operated, the film f is melted and welded, and the packaged article a is transferred to the next heat tunnel (not shown) on a discharge belt conveyor 18. It is starting to be sent.

The device of this invention consists of the structure of the seal pedestal 14 and the L sealer 15, and especially the shape of the cutting blade 37 thereof.

The seal pedestal 14 has a receiving plate 4 on the upper surface of the base 39.
A pair of left and right seal cushions 41, 41 are provided on the upper surface of the receiving plate 40, and a gap is left between the two seal cushions 41, 41 to form a concave groove 42 into which the cutting blade 37 enters. It is provided. The receiving plate 40 is made of silicone rubber, and the seal cushions 41, 41 are made of sponge-like rubber.

In the L-sealer 15, a heat bar 20 is fixed to the base frame 19 in a spaced manner via connecting pieces 21 and 22, and a blade portion 38 of a cutting blade 37 protrudes from the center of the width of the heat bar 20. . Further, film pressers 23, 23 which also serve as heat insulation covers are provided on both sides of the heat bar 20, and both film pressers 23, 2
3 is biased downward by a spring 26.

The heat bar 20 consists of left and right half members 33, 33 made of a metal with good thermal conductivity such as an aluminum alloy or a copper alloy, and has a pipe heater 2 in the center.
7 through holes 28 are provided, and a split groove 29 is formed below the through hole 28 to sandwich the cutting blade 37.
An opening 30 opening in an inverted V shape is provided at the lower end of the opening 9. Then, the cutting blade 37 is fixed by tightening both half members 33, 33 with screws 34, and the cutting blade 37 is made to protrude to a length reaching the receiving plate 40 of the seal holder 14.

The cutting blade 37 has a blade portion 38 formed by an inclined surface at the lower end of a length-shaped main body 37a made of metal with good thermal conductivity.
In addition, by continuously providing the chevron-shaped notches 45, the blade portion 38 is formed into a sawtooth shape, and has cutting edges 46 dotted at intervals. Further, the elongated main body 37a has elongated holes 4 through which screws 34 are inserted at appropriate intervals.
8 is provided.

The cutting blade 37 and the heat bar 20 are coated with Teflon to prevent film from adhering to them.

In the above embodiment, the article a placed on the belt conveyor 2 enters the film f opened by the opening device 5 and is wrapped by the sealing device 1. 15 is lowered, as _shown in FIG _.
Since f ₁ and f ₂ are strongly stretched over the groove 42 between the seal cushions 41 and 41, when the cutting edge 46 of the cutting blade 37 enters the groove 42 as shown in FIG. ₁ , it breaks through f ₂ .

Even if the cutting edge 46 breaks through the films f ₁ and f ₂ , a film 49 (black portion) remains between the cutting edges 46 as shown in FIG. 5, but the cutting edge 46 moves upward. Since the remaining film 49 is thicker and retains a larger amount of temperature, the slope 51 of the remaining film 49 is
The remaining amount is reduced by being fused and melted. That is, the number of cuts gradually increases in the films f ₁ and f ₂ .

Next, as shown in FIG. 4c, the heat bar 20
When the two half members 33, 33 press the films f ₁ , f ₂ onto the seal cushions 41, _{41, both the films f 1 , f 2 are} welded. In order to press it even more firmly, use the cutting edge 4.
6 becomes easier to bite into, and cut blade 3
7 and the half members 33, 33 on both sides thereof, the films f ₁ and f ₂ shrink outward (in the direction of arrow P) by receiving high heat, so that a tear 52 is created by the blade 38. The shrinking action causes further tearing, and both the upper and lower films f ₁ and f ₂ are completely cut.

Further, since the seal cushions 41, 41 are made of sponge-like rubber that easily causes friction, the lower film _f2 , which is fused thereto, is likely to be immovably pressed by the cutting blade 37 and the half members 33, 33. , due to this, the cutting edge 46 to the films f ₁ and f ₂
The biting becomes good.

[Effects of the invention] As explained above, according to this invention, the blade portion of the cutting blade is formed into a sawtooth shape with sharp cutting edges protruding at equal intervals, and the seal pedestal has a cutter in the center of the upper surface width. A groove into which the cutting edge of the cutting blade can penetrate is provided, and the upper and lower films on the seal holder are fixed and stretched over the groove so that they do not shift due to the pressure of the film holder. It penetrates through the film and reliably forms a tear in it, and since the upper and lower films easily receive heat from the cutting blade and heat bar, the tear expands and continues all at once due to film melting and heat shrinkage, making it possible to operate both the upper and lower films in one step. It has the excellent effect of being able to cut reliably.

In particular, the cutting and welding apparatus of the present invention exhibits remarkable effects when used for so-called laminate films (for example, gas barrier films) in which films are laminated in multiple layers.

Note that similar actions and effects can be obtained by using the device of the present invention not only for L-shaped sealers but also for half-folding sealers and the like.

[Brief explanation of the drawing]

The drawings show one embodiment, and FIG. 1 is a partial longitudinal sectional view, FIG. 2 is a front view of the cutting blade, FIG. 3 is a sectional view taken along the line A-A in FIG. 2, and FIG. 4 is a film. Explanatory diagram showing the fusing and welding procedure in the order of figures a, b, and c, No. 5
The figure is an explanatory view showing the cutting state of the cutting blade into the film, and FIG. 6 is a perspective view of the packaging machine showing an example of use. 14... Seal pedestal, 15... Sealer, 20...
...Heat bar, 23...Film presser, 37...
Cutting blade, 38...Blade portion, 41...Seal cushion, 42...Concave groove, 46...Blade tip, f...Film, _f1 ...Upper film, _f2 ...Lower film.

Claims (1)

[Claims for Utility Model Registration] 1. A plastic film fusing and welding device that is equipped with a seal bar and a seal pedestal, stores an article to be packaged inside, and sequentially fusing and seals bi-folded films that are intermittently supplied, The seal bar has a cutter blade whose blade protrudes from the sealing surface of the seal bar at the center of the width thereof, and the blade part is formed into a saw blade shape with sharp cutting edges arranged at equal intervals. A fusing and welding device for plastic film, characterized in that a groove large enough for the cutter blade to be loosely fitted therein is formed on the surface of the seal holder facing the cutter blade. 2. On the seal surface sandwiching the groove of the seal pedestal,
A plastic film fusing and welding apparatus according to claim 1, which is provided with a sealing member made of an elastic material. 3. The plastic film fusing and welding apparatus according to claim 1, wherein the plastic film is a laminate film.