JPH06345058A - Trowel for heat-seal - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a heat-sealing iron capable of performing complete heat-sealing even when the surface shape of the packaged object has irregularities and steps. [Structure] A heat part of a heat-sealing iron is composed of a substrate, a pressure element, and a heating element. The pressure element is connected to the substrate with an elastic body such as a coil spring interposed therebetween, and the tip side is connected to the tip side. The structure has a heating element interposed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a heating iron used for heat-sealing an object to be packaged.

[0002]

2. Description of the Related Art When a finished product is put in a cardboard or the like and packed in a factory for manufacturing electric products, it is common to wrap the entire surface with a thin sheet in order to protect the surface of the product.

In such a case, conventionally, the product was wrapped in a sheet and the overlapping portion of the sheet was sealed by adhering it with a vinyl tape or the like, but this takes time for the packaging work and the vinyl tape or the like is peeled off. It was easy and the packaging was not good. Therefore, recently, a heat-sealing packaging method has been developed and popularized, which enables the packaging work to be performed easily and in a short time, and has a beautiful finish.

That is, in heat seal packaging, as shown in FIG. 5, the object to be packaged 1 is wrapped with an overlap film 2,
The heated metal iron 3 is pressed against the overlapping portions 2a at the left and right ends to apply a pressure P to bond the two overlapping films of the overlapping portions 2a.

[0005]

However, the structure of the heat-sealing trowel according to the prior art described above has no problem when the surface shape of the object to be packaged 1 is flat, but the structure of the object to be packaged 1 If there are irregularities or steps on the surface,
There were the following problems.

For example, as shown in FIG. 6, when the surface of the article to be packaged 1 has a concave portion 1a, when it is wrapped with an overlap film 2, the concave portion 1a of the article to be packaged 1 and the overlap film 2 are wrapped. There is a gap between and.

In this state, when the trowel 3 is applied to the overlapping portion 2a of the overlap film 2 and a pressure P is applied, the trowel 3 is a rigid body, so that the wrapping object 1 and the trowel 3 are separated from each other. The pressure distribution 4 of the pressure applied to the sandwiched overlap film 2a becomes non-uniform as shown in FIG.

That is, the portion W of the overlap film 2 corresponding to the concave portion 1a of the article to be packaged 1 is not pressed by the iron 3 and the article to be packaged 1 from both sides with a sufficient pressure.
There has been a problem that the adhesion of the part becomes insufficient or no adhesion occurs at all.

Therefore, even if the surface of the article to be packaged has a surface shape having irregularities or steps, the structure of the heat-sealing trowel is such that the pressure distribution applied to the overwrapped film is uniform. It has problems that must be solved.

[0010]

In order to solve the above-mentioned problems, a heat-sealing iron according to the present invention is a heat-sealing iron having a heat portion for heat-welding overlapping portions of a film or sheet member. Therefore, the heating portion is configured to follow the shape along the surface shape of the overlapping portion.

Further, the heating section comprises a substrate, a plurality of pressurizers arranged on the substrate via elastic bodies, and means for heating the pressurizers; the elastic body comprises a coil spring. The elastic body is a leaf spring; the elastic body is a heat-sealing trowel that also serves as heating means.

[0012]

With the above structure, the heat-sealing trowel according to the present invention is adapted to follow the surface shape of the object to be packaged. When the heat portion of the heat-sealing iron is brought into contact with the overlapping portion wrapped with, uniform pressure is also applied to the overlapping film in the portion corresponding to the uneven portion and the step, and complete heat sealing is performed.

Further, the heat-sealing trowel according to the present invention,
By configuring the substrate, a plurality of pressurizers connected to the substrate via elastic bodies, and a means for heating the pressurizer, each pressurizer is heated by the heating means at a temperature suitable for heat sealing. In addition, the distance between the tip of each presser and the substrate can be independently changed by the action of the elastic body.

That is, the heat portion of the heat-sealing iron is
If the pressure is applied to the substrate from above by applying it to the overlapping part of the film or sheet member that wraps the packaged object, all the pressurizers will be The film or sheet member can be heated and welded by abutting against corresponding portions of the surface of the package with a uniform pressing force.

Further, when the elastic body constituting the heating portion of the iron is constituted by the coil springs unique to each pressurizer, each pressurizer is independently expanded and contracted by each coil spring, and as a result, the tip of each pressurizer is wrapped. Accurately follows the surface shape of an object. Therefore, the heat-sealing trowel using the coil spring in the heating part is suitable for a packaged object having a complicated surface shape.

Further, when the elastic body constituting the heating section is constituted by, for example, one leaf spring common to a plurality of pressurizers,
The independence of the operation of each presser is less than in the case of the coil spring shown in the previous term. However, for example, when the surface shape of the article to be packaged changes relatively gently, the structure can sufficiently follow it. With this structure, a simple and low-cost heat sealing iron can be obtained.

If the elastic body forming the heating portion of the iron has a heating means, the heat-sealing iron can be made smaller and lighter.

[0018]

Embodiments of the heat-sealing iron according to the present invention will be described below with reference to the drawings. As shown in FIG. 1, the heat section 5 of the heat-sealing iron according to the first embodiment of the heat-sealing iron according to the present invention includes a substrate 6, a plurality of pressurizers 7, a plurality of coil springs 8, Heating element 9 and substrate 6
And a connecting plate 10 that connects the heating element 9 with each other.

The substrate 6 is formed of a suitable lightweight rigid material in the shape of an elongated rectangle, and its length is appropriately determined by the length of the object to be heat-sealed. Further, since the substrate 6 directly receives the external pressure from above when heat sealing is performed manually or automatically, it has a structure having a strength capable of withstanding the external force.

The pressurizer 7 is formed of a plurality of heat conductors such as metal and ceramics, and is formed in a cylindrical shape having the same size. A lower end of a coil spring 8 having a predetermined length and a predetermined elasticity is connected to each of the pressurizers 7 to form a unit (unit component). The presser 7
If a flange portion is provided on the upper surface of the heat generating element 9 and the flange portion is brought into contact with the upper surface of the heat generating element 9, the tip of each pressurizing element 7 will be the heat generating element 9.
It can be maintained so that it projects the same length from the underside of the. Further, the pressurizing element 7 and the coil spring 8 which is an elastic body may not be connected to each other, but may be biased by the coil spring 8 from above the position determined by the flange portion described above.

A required number of units including the pressurizers 7 and the coil springs 8 are arranged in a line in the longitudinal direction of the substrate 6 at equal intervals, and the upper ends of the coil springs 8 are arranged on the substrate 6.
Connect to the underside of.

Note that the smaller the diameter of the pressurizer 7 and the smaller the arrangement intervals, the more the pressurizers 7 are arranged and the better the followability of the iron 5 to the surface shape of the article 1 to be packaged. Of course, the units described above can be arranged in a plurality of rows, and by doing so, it is possible to follow the three-dimensional surface shape of the article to be packaged 1.

The heating element 9 is formed in a plate shape having the same length as the substrate 6, and has a function of generating heat by electric heat or the like. The heating element 9 is provided with through holes 9a in the same number as the pressurizing elements 7 in the longitudinal direction at the same intervals as the pressurizing elements 7. Through hole 9a
The diameter of is slightly larger than the diameter of the pressurizer 7.

Each pressurizing element 7 is inserted into the corresponding through hole 9a of the heating element 9 so that the tip of the pressing element 7 projects from the lower surface of the heating element 9 by an appropriate length. And the heating element 9
Is fixed in parallel to the substrate 6 by a connection plate 10 made of a heat insulating material and at a position as close to the tip of the pressurizer 7 as possible.

In this way, each pressurizing element 7 is heated through the through hole 9a of the heating element 9 to maintain the temperature required for heat sealing, and the elastic force of the coil spring 8 with the upper end of the coil spring 8 as a fulcrum. Thus, it is possible to freely slide up and down through the through hole 9a.

That is, the distance between the tip of the pressurizing member 7 and the substrate 6 is structured so that it can be freely expanded and contracted by the action of the coil spring 8. In addition, in the pressurizer 7,
It goes without saying that the movable range can be limited by attaching a stopper by the flange portion, which has been described in the previous term, to make it urged.

Now, in order to perform heat sealing of the article to be packaged 1 wrapped by the film or sheet member (overlap film in the embodiment) 2 by the heat portion 5 of the heat sealing iron having the above-mentioned structure, After setting the heating portion 5 of the trowel on the overlapping portion of the wrap film 2, a downward pressure P is applied to the substrate 6.

Then, when the surface of the article to be packaged 1 is flat, the tips of the pressurizers 7 abut the overlap film 2 almost at the same time, and the contracted lengths of the coil springs 8 are the same. Uniform pressure is applied to the overlap film 2 so that heat sealing is completely performed at one time.

However, as shown in FIG. 2, when the surface of the article to be packaged 1 has an uneven shape, the overlap film 2 is in close contact with the surface of the article to be packaged 1 in the flat portion. For example, as soon as the pressurizer 7 corresponding to the portion indicated by the arrow A comes into contact with the overlap film 2, pressure is applied to the overlap film 2 and heat sealing is performed.

Further, in the uneven portion and the stepped portion of the article to be packaged 1, for example, the portion shown by the arrow B, since the overlap film 2 and the surface of the article to be packaged 1 are separated from each other, the presser 7 is placed in the overlap film 2. Even if it comes into contact with, the overlap film 2 is not pressured. That is, as described above, this was a problem with the conventional rigid heat-sealing iron.

In the structure having the heat portion 5 of the heat-sealing iron according to the present invention, even if the package 1 has the uneven portion and the step, for example, the pressurizer 7 contacts a part of the convex portion. Even if they come into contact with each other, the expansion and contraction of the coil spring 8 keeps pressing the substrate 6 and brings the substrate 6 close to the object to be packaged 1 to follow the surface shape of the object to be packaged 1 having irregularities and steps. Uniform pressure can be applied.

That is, when a pressure is further applied to the substrate 6 to overcome the resistance of the coil spring 8 connected to the pressurizer 7 already in contact with the article to be packaged 1, the coil spring 8 contracts and the substrate 6 The object 1 is approached by the contracted length of the coil spring 8.

According to this principle, when pressure is continuously applied to the substrate 6, the substrate 6 out of the surface of the article to be packaged 1 is
From the closest position to the farthest position (recess), the presser 7 sequentially pushes the overlap film 2 and abuts the object to be packaged 1, and as a result, all the pressers 7 are uneven on the overlap film 2. It is possible to perform heat welding by applying a uniform pressure following the shape of the portion, and complete heat sealing can be performed.

The heat section 5 of the heat-sealing iron, which is composed of a unit consisting of the pressurizer 7 and the coil spring 8, is
Since each unit can be independently expanded and contracted, the conformability to the surface shape of the article to be packaged 1 is good. Further, since the number of units can be arbitrarily selected depending on the object of heat sealing, there is versatility. Furthermore, since individual units can be replaced, maintainability is excellent.

In the above embodiment, the heating element 9 heats the pressurizer 7 through the wall surface of the through hole 9a.
It is not necessary to heat the entire heating element 9, and any structure can be used as long as it can heat the pressurizer 7 through the wall surface of the through hole 9a.

Therefore, the structure may be such that only the wall surface portion of the through hole 9a has a heat generating function, and as a modification thereof, the pressurizing member 7 itself has a heat generating function.
A unit composed of a pressurizer that generates heat and a coil spring 8 can be used. In this case, the reference numeral 9 shown has only a function as a guide for sliding the pressurizer 7 up and down.

Next, the heat part 11 of the iron which is the second embodiment of the heat-sealing iron according to the present invention is shown in FIGS.
2, the substrate 6, the plurality of pressurizers 7, and the heating element 9
And a leaf spring 12.

The substrate 6 is formed of a suitable lightweight material in the shape of an elongated rectangle. The length of the substrate 6 is appropriately selected according to the length of the object to be heat-sealed. The substrate 6 is formed in an appropriate shape so that it can be easily gripped. Further, the substrate 6 directly receives an external pressure manually or automatically when heat-sealing, so that the substrate 6 needs to have a strength capable of withstanding the external force.

The pressurizer 7 is made of a heat conductor such as metal or ceramic and is formed into a cylindrical shape having the same size. The upper end of each pressurizer 7 is connected to the central portion 12a of the leaf spring 12 at equal intervals.

The leaf spring 12 is composed of one strip-shaped thin elastic plate. That is, both end portions of the elastic plate are bent in the same direction at a right angle, and the corrugated portions 12b and 12c are formed in the bent portions. Both ends of the leaf spring 12 thus formed in a U-shape are fixed to the lower surface of the substrate 6.

The central portion 12a of the leaf spring 12 thus formed is parallel to the lower surface of the substrate 6 when there is no pressure. The leaf spring 12 is movable up and down by the expansion and contraction of the corrugated portions 12b and 12c, and the distance between any point of the central portion 12a and the substrate 6 is maximum depending on the pressure applied to that point. It takes a value between the value C (see FIG. 3) and the minimum value D (see FIG. 4).

The heating element 9 is formed in the same length as the substrate 6 and has a function of generating heat by electric heat or the like. The heating element 9 is provided with through holes 9a in the longitudinal direction at the same intervals as the pressurizing elements 7 and in the same number as the pressurizing elements 7. The diameter of the through hole 9 a is slightly larger than the diameter of the pressurizer 7.

Each pressurizing member 7 is provided with a corresponding through hole 9a.
And the tip is projected from the lower surface of the heating element 9 by an appropriate length. Then, the heating element 9 is fixed in parallel to the substrate 6 and at a position near the tip of the presser 7 by the connection plate 10 made of a heat insulating material. As described in the first embodiment, if each pressurizing element 7 is provided with a flange portion and the flange portion is brought into contact with the upper surface of the heating element 9,
The tip of the pressurizer 7 can be maintained so as to protrude from the lower surface of the heating element 9 by the same length.

In this way, the pressurizer 7 is heated through the through hole 9a of the heating element 9 and is maintained at a temperature suitable for heat sealing, and at the same time the leaf spring 12 causes the through hole 9a.
It has a structure that allows it to slide up and down freely inside.

That is, the distance between the tip of the pressing element 7 and the substrate 6 can be freely expanded and contracted by the action of the leaf spring 12. As described above, it goes without saying that the pressurizer 7 can be provided with a stopper such as a flange to limit the movable range. Further, the pressurizing member 7 may be positioned and arranged by a flange portion and may be biased by the leaf spring 12.

Now, the heating part 11 of the trowel having the above structure
In order to perform the heat sealing of the article to be packaged 1 wrapped with the overlap film 2, by setting the heating part 11 of the trowel on the overlapping part of the overlap film 2 as shown in FIG. Downward pressure P on the substrate 6
Add.

Then, when the surface of the object to be packaged 1 is flat, the tips of the pressurizers 7 simultaneously contact the overlap film 2, and the central portion 12a of the leaf spring 12 and the substrate 6 are contacted.
That is, the distance is reduced while maintaining the parallelism, and therefore, the overlap film 2 is heated and welded under a condition that a uniform pressure is applied, and the heat sealing is simultaneously performed completely.

However, as shown in FIG. 4, when the surface shape of the article to be packaged 1 has irregularities, the overlap film 2 is in close contact with the surface of the article to be packaged 1 at the flat portion. As soon as the pressurizer 7 corresponding to the portion comes into contact with the overlap film 2, the overlap film 2 is immediately released.
Heat is applied by applying pressure to.

However, since the overlap film 2 and the surface of the object to be packaged 1 are separated from each other in the uneven portion and the stepped portion, the pressurizing element 7 is used for the overlap film 2.
Even if it comes into contact with, the overlap film 2 is not pressured.

In the heat section 11 of the heat-sealing iron, due to the expanding and contracting function of the leaf spring 12, even if the pressurizer 7 has already abutted on a part of the article to be packaged 1, the substrate 6 is still pressed. The substrate 6 can be brought close to the article to be packaged 1.

That is, even if the existing pressurizer 7 is in contact with the object to be packaged 1, when the pressure that overcomes the resistance of the leaf spring 12 is further applied to the substrate 6, the leaf spring 12 is compressed and the substrate 6
Approaches the object to be packaged 1.

According to this principle, when pressure is continuously applied to the substrate 6, the substrate 6 out of the surface of the article to be packaged 1 is
From the closest position to the farthest position (recess), the pressure element 7 sequentially presses the overlap film 2 and contacts the object to be packaged 1, and as a result, all the pressure elements 7 are overlapped. A uniform heat is applied to the product, and complete heat sealing is performed.

The heat portion 11 of the heat-sealing iron constituted by the leaf spring 12 has a followability with respect to the surface shape of the article to be packaged 1 as compared with the heat portion 5 of the iron using the coil spring 8 of the first embodiment. Although it is inferior, it has an advantage of low manufacturing cost because of its simple structure.

Further, as a third embodiment of the heat-sealing iron according to the present invention, an elastic body having a heat generating function may be attached to the substrate 6 and a plurality of pressurizers may be attached to the elastic body. . In this way, the heating element 9 as shown in FIGS. 1 to 4 becomes unnecessary, and a heat-sealing iron having a simpler structure can be obtained.

[0055]

As described above, since the heat portion of the heat-sealing iron according to the present invention is deformed according to the surface shape of the packaged object, even when the packaged object has irregularities or steps. Since heat welding can be performed by applying pressure evenly, it is possible to eliminate the incomplete heat sealing of uneven portions and stepped portions as in the conventional case, and to improve the reliability of heat sealing. Play.

Further, in order to follow the surface shape of the article to be packaged, a plurality of heated pressurizers are arranged on the substrate through an elastic body, so that the heat part of the heat-sealing iron is heated. There is an effect that can be realized easily and at low cost.

In particular, by constructing the elastic body with a coil spring unique to each pressurizer, a heat-sealing iron which follows the surface shape of the article to be packaged very faithfully and has high versatility and maintainability is realized. There is an effect that can be said.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing the configuration of a heat-sealing iron according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of an operation of the embodiment.

FIG. 3 is an explanatory diagram showing the structure of a heat-sealing iron according to a second embodiment of the present invention.

FIG. 4 is an explanatory diagram of an operation of the embodiment.

FIG. 5 is an explanatory view showing a heat-sealing iron according to the prior art.

FIG. 6 is an explanatory diagram showing a relationship between the trowel and an article to be packaged having an uneven portion and a step.

FIG. 7 is an explanatory diagram showing a pressure distribution of the trowel.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Packaged object 1a Recess 2 Overlap film 2a Overlap film overlapping part 3 Trowel 4 Pressure distribution curve 5 Heat part 6 Substrate 7 Pressurizer 8 Coil spring 9 Heating element 9a Through hole 10 Heat insulating material 11 Heat part 12 Leaf spring 12a Center part 12b, 12c of leaf spring 12 Corrugated part P Pressure

Claims (5)

[Claims] 1. A heat-sealing trowel comprising a heating portion for heating and welding an overlapping portion of a film or sheet member, wherein the heating portion follows a shape along the surface shape of the overlapping portion. Trowel for heat sealing, which is characterized by 2. The heating unit comprises a substrate, a plurality of pressurizers arranged on the substrate via an elastic body, and means for heating the pressurizer. Trowel for heat seal described. 3. The heat sealing iron according to claim 1, wherein the elastic body is a coil spring. 4. The heat-sealing iron according to claim 1, wherein the elastic body is a leaf spring. 5. The iron for heat-sealing according to claim 2, wherein the elastic body also serves as the heating means.