JPH0788085B2 - Assembled case - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention relates to an assembling type case using a composite corrugated body constituted by adhering a flat plate liner material to a corrugated core body.

<Prior Art> As a conventional composite corrugated body, a corrugated core is formed by arranging a large number of corrugated rows formed by alternately providing vertical peaks and troughs on a sheet material in a plane straight line. ,
A single-sided cardboard in which a flat plate liner is bonded to one surface of this corrugated core or a double-sided cardboard in which a flat plate liner is bonded to both surfaces of a corrugated core is known.

When the single-sided cardboard and the double-sided cardboard are compared, the single-sided cardboard is far more advantageous in terms of cost. Therefore, it is conceivable to use the single-sided cardboard to form the assembled case. To use the single-sided cardboard 1 to make a prefabricated case 5 in which the flap pieces on the upper surface can be opened and closed as shown in FIG. 10 (A), normally, as shown in FIG. 10 (B). Corrugated row 2 as shown
-2 is orientated in the lateral direction of the blanks and cut into a predetermined size as shown in the drawing, and a ruled line is attached and supplied to an automatic box making machine to make a box.

<Problems to be Solved by the Invention> However, in the conventional single-sided cardboard, the in-plane compressive strength in the x direction orthogonal to the corrugated row 2 in FIG. 10 (A), that is, in the lateral grain direction of the cardboard is extremely low. turn into. Therefore, for example, as shown in FIG. 10 (C), when the corrugated strips 2 are arranged along the longitudinal direction of the case to form the assembly type case as shown,
Since the case is extremely weak against the load from above, it is usually necessary to cut as shown in Fig. 10 (B) and make the box as shown in Fig. 10 (A). Will be limited.

Further, in the conventional single-sided cardboard, the out-of-plane bending strength in the vertical plane direction orthogonal to the x direction in FIG. 9 is also extremely low and it is easy to bend. Therefore, the assembly type case shown in FIG. In addition, when wet, the bottom surface is likely to slip out.

Since the in-plane compressive strength and the out-of-plane bending strength are low as described above, in the conventional assembly type case, the flap piece (I) in the opening portion of the case is folded while the body is folded and flattened when not in use. (III) was curved or bent, and was easily damaged, and the storage efficiency of the contents was reduced.

Furthermore, since the conventional one-sided cardboard has low out-of-plane compression strength, it is not possible to obtain sufficient cushioning properties on each side of the case, and as a result, as a case for storing and carrying relatively heavy contents or a relatively large assembly type. It was totally unsuitable as a case.

Further, in the conventional single-sided cardboard 1, since the joint portion between the corrugated strip 2-2 and the flat plate liner 4 becomes a parallel line shape along the mountain portion of the corrugated strip 2-2, this single-sided cardboard ruled line is attached. If the part matches the parallel line part, it is easy to bend along that part, but if the other scoring parts are misaligned with respect to the parallel line part, accurate bending along the ruled line will occur. It was difficult.

That is, in the conventional single-sided cardboard, it is difficult to accurately bend the crease forming part in the longitudinal direction (y direction) of the corrugated row, and the dimensional accuracy of the case is significantly impaired during the box making process. Only the part corresponding to the periphery of the above has a high cost structure such as a double-sided liner attached or a double core for reinforcement.

Also, the conventional single-sided cardboard is apt to warp and deform,
Stripe-shaped grooves are formed on the flat plate liner surface, resulting in poor printability.
It was not suitable for precision printing such as POS bars.

Further, as is clear from FIG. 10 (B), the unfolded sheet of single-sided cardboard for forming the assembling type case must be cut so that the corrugated row direction is the lateral direction. It has been pointed out that since the cutting direction is limited, edge cutting is likely to occur and cutting efficiency is reduced.

The present invention has been made in view of the above problems,
Its purpose is to have sufficient strength in all of in-plane compressive strength, out-of-plane bending strength and out-of-plane compressive strength, and therefore cut in any direction of the corrugated row without being constrained in the arrangement direction of the corrugated row. (EN) An assembling type case that can be made into a box and that is unlikely to cause bulging of the body or slipping out of the bottom, accurate dimensional accuracy of the crease marking part, excellent printing suitability, and improved cutting efficiency. It is in.

<< Means for Solving the Problems >> In order to achieve the above object, in the assembling type case according to the present invention, a corrugated row is formed by alternately applying vertical peaks and troughs to the sheet material. Along with the corrugated rows meandering in a plane waveform, the amplitude ratio H / L (L: wavelength, H: amplitude) of each cross-sectional wave of the corrugated rows is set to 0.2 or more, and the corrugated rows between the corrugated rows in the planar shape are Meandering polymerization rate D / L
(D: the amplitude of the plane meandering wave) is 0.5 or more, and further, the meandering ratio D / N (N: the wavelength of the plane meandering wave) of each corrugated row in the planar shape is 0.15 or more to form a corrugated core body, A flat plate liner is bonded to at least one surface of the corrugated core body to form a reinforced composite corrugated body, and the composite corrugated body is provided with ruled lines that define four rectangular sections continuous in the lateral direction in the development view, and each rectangle Upper and lower flap pieces that can be independently bent are formed above and below the upper and lower ruled lines of the section, and a margin is formed on the side edge of the rectangular section at either one of the left and right side ends. The rectangular section is folded along the ruled line, and the margin is adhered to the rectangular section at the other side end so that the upper flap piece can be opened and closed to make a box.

<Example> Hereinafter, a preferred example of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an example of a single-sided reinforced composite corrugated body 10 which constitutes an assembling type case according to the present invention, which is composed of a corrugated core body 11 and a flat plate liner 12. This corrugated core body 11 is a corrugated row 13 formed by alternately forming peaks M and valleys V in the vertical direction in the x direction.
Are made to meander in a wavy shape in the y direction in a plane, and these corrugated rows are parallel to each other. Then, the flat plate liner 12 is mounted on the corrugated row at the mountain portion M of the corrugated row 13.
It is glued together with 13.

The shape of the corrugated strips 13 of the corrugated core body 11 is defined by the amplitude ratio H / L, the meandering polymerization ratio D / L, and the meandering ratio D / N in FIG. Here, the amplitude ratio H / L indicates the relationship between the amplitude H and the wavelength L of the cross-sectional wave obtained by cutting the corrugated row 13 along the vertical plane in the x direction in FIG. 1, and FIG.
(F) shows the amplitude ratio when H is kept constant and L is variously changed. As is clear from this figure, as the amplitude ratio increases significantly, the cross-sectional wave rises with an angle θ formed between it and the bottom gradually increasing, and as a result, an out-of-plane wave applied vertically downward from the peak of the cross-sectional wave. It can be said that the strength against the compressive force increases in proportion to the angle θ. When H / L is too small, not only the out-of-plane compressive strength is small, but also the distance between adjacent corrugated rows is naturally increased, and the number of corrugated rows included in the corrugated core body of a predetermined area is increased. Also less. Therefore, the practical range is H / L ≧ 0.2.

As shown in FIG. 1 and FIG. 3, the meandering polymerization rate D / L shows the relationship between the amplitude D of each corrugated strip and the wavelength L of the cross-sectional wave when the corrugated strip is viewed in plan. Shows.

Here, FIG. 3A shows the joining state between the adjacent corrugated strip rows 13a and 13b and the flat plate liner 12 when the amplitude D and the wavelength N of the plane wave of the corrugated strip are kept constant and the wavelength L of the sectional wave is sequentially changed. )-(E). These drawings (A) to (E) show the corrugated rows in a plan view, and the tops of the corrugated rows 13a and 13b adjacent to each other in the x direction.
M ₁ and M ₂ are shown by a solid line in a meandering shape, the valley bottom V of both rows is shown by a dotted line, S ₂ is an upper tangent of the valley bottom V, S ₃ is a central transverse line of the valley bottom V, B is a single-sided reinforced composite corrugated body 10
Shows the bottom surface of.

When D / L = 0.4 in FIG. 3 (A), at the cross-sectional position along the line S ₁ , as shown in FIG. 3 (A1), the corrugated strip 13
Only the top portion of a is joined to the flat plate liner 12 at equal intervals with the wavelength N of the corrugated strip, and the whole is in a state of being lifted from the bottom surface B of the composite corrugated body. On the other hand, S ₂
At the cross-sectional position along the line, as shown in FIG. 3 (A2), the corrugated strip 13a has the valley bottom V at the same level as the wavelength N and at the same level as the bottom surface B of the composite corrugated body, but the entire corrugated strip 13a is a flat plate liner. Separated from twelve. At the cross-section position along S ₃ , both corrugated strips 13a, 13a,
The central portion of 13b is at the same level as the bottom surface B of the composite corrugated body at an interval of 1/2 of the wavelength N, but the whole is largely separated from the flat plate liner 12 as in the case of the cross-sectional position along the line S ₂ above. is doing.

Thus, when D / L = 0.4, when cut in the y direction at an arbitrary position orthogonal to the x direction, the corrugated strip at the cut position is floating from the bottom surface B of the composite corrugated body or separated from the flat plate liner 12. ing. Such a state always occurs when D / L <0.5.

That is, when the cross sections (A ₁ ), (A ₂ ), and (A ₃ ) of the single-sided reinforced composite corrugated body with D / L <0.5 are viewed as a truss structure,
Since there is no portion where the portion corresponding to the web of the truss extends to the entire wall thickness (T) of the composite corrugated body, the first truss structure has a low bending strength in the vertical plane direction orthogonal to the x direction.

Then, when the D / L = 0.5, as shown in FIG. 3 (B), S ₁
The line and the line S ₂ are overlapped with each other, and at the cross-sectional position along the lines S ₁ and S ₂ , as shown in FIG. 3 (B1), the corrugated strip 13a is joined to the flat plate liner 12 at equal intervals with the wavelength N. At the same time, it is at the same level as the bottom surface of the composite corrugated body 10. Thus, when D / L = 0.5, when D / L = 0.4, other D / L
Compared to the case of L <0.5, when the cross section along the S ₁ / S ₂ line is viewed as a truss structure, the web of the truss extends to the entire thickness of the composite corrugated body, and D / L < It can be said that the structure changed to the second truss structure, which is qualitatively different from the case of 0.5, and the out-of-plane bending strength in the y direction is significantly increased as a whole. That is, in the second truss structure, the angle of inclination of the web of the truss becomes steep, and the number of triangular truss units composed of the web material (the line segment of the inclining corrugated body) and the flange material (horizontal flat liner) becomes steep. Is increasing.

Then, as a further strengthened structure without changing the quality of the second truss structure, there is a structure in which D / L exceeds 0.5, for example, D / L = 0.8, and FIG. 3 (C1) and As is clear from (C2), regarding the unit length in the y direction of the cross section between the S ₁ line and the S ₂ line, the location where the corrugated strip 13a is joined to the flat plate liner 12 and the bottom surface of the composite corrugated body are the same. The number of levels is increased, the truss configuration density is further increased, and the out-of-plane bending strength between the S ₁ line and the S ₂ line and also between the S ′ ₁ line and the S ′ ₂ line is increased. However, S ₁ line ~ S '
_In the section between the ₁ lines (not including these lines), as is clear from FIG. 3 (C3) showing the cross-sectional positions along the S ₃ line, all the corrugated strips 13a, 13b at these cross-sectional positions are Separated from flat liner 12.

Further, when D / L = 1.0, as shown in FIG. 3 (D), line S _{1 and} line S ₃ overlap, and at the cross-sectional position along this line, corrugated strips 13a and 13b have wavelength N. It is joined to the flat plate liner 12 at an interval of 1/2 of the above and extends in a corrugated shape to the bottom level B of the composite corrugated body. Therefore, D / L =
In the state of 1.0, FIG. 3 sections as shown in S ₁ line to S _'1 line in (C) disappears, in any cross-sectional position orthogonal to the x-direction, the corrugated strip 13a, 13b than the wavelength N It is joined to the flat plate liner 12 at a sufficiently small interval and extends to the bottom level of the composite corrugated body. When viewed as a truss structure, the truss is composite at any position orthogonal to the x direction. In order to extend the entire thickness of the corrugated body, the structure has changed to the third truss structure where the structure has undergone a further qualitative change compared to the case of 0.5 ≦ D / L <1.0, and the maximum out-of-plane bending strength is 0.5 ≦ Compared with the case of D / L <1.0, it will be further increased. That is, the web inclination angle of the unit triangular truss is steeper than that of the second truss structure, and more points are joined to the flat plate liner 12 or the bottom level B of the composite corrugated body is increased.
Further, the number of triangular truss units made of the web material and the flange material is further increased.

Further, there is a third truss structure which is further strengthened without changing its quality and has a D / L exceeding 1.0, for example, 1.2. In this case, FIG. 3 (E1) ，
As shown in (E2), the wave front of the waveform extending between the flat plate liner 12 and the composite corrugated body is sharpened at an arbitrary cross-sectional position orthogonal to the x direction as compared with the case where D / L = 1.0, That is, the web inclination angle of the unit triangular truss becomes steeper, more joints are formed with the flat plate liner 12 or more portions reach the bottom level B of the composite corrugated body, and the out-of-plane maximum bending strength is further increased. This tendency is considered to increase in proportion to the increase in D / L.

The above relationship between the meandering polymerization rate D / L and the out-of-plane maximum bending stress index M is shown in a graph when the amplitude rate (H / L = 0.1, 0.2, 0.3, 0.4, 0.5, 0.6) is used as a parameter constant. As shown in the figure. That is, when D / L <0.5, each corrugated strip is separated from the flat plate liner 12 in the y-direction cross section at an arbitrary position in FIG. 1 or the bottom surface (B) of the composite corrugated body.
Out of plane bending strength is relatively small because
The truss structure of gradually increases as the D / L approaches 0.5. When D / L = 0.5, there is a part of the cross section of the corrugated strip in the y direction that is joined to the flat plate liner and is at the same level as the bottom surface of the composite corrugated body.
It suddenly shifts to a second truss structure, which is qualitatively different from the case of 0.5, whereby the increase rate of the out-of-plane bending strength becomes much larger than before. As the D / L increases beyond 0.5, it is joined to the flat plate liner as described above, and becomes the same level as the bottom surface of the composite corrugated body in the x-direction section of the y-direction cross section (S ₁ ~ in FIG. 3C). since the number of structurally advantageous triangular truss units between S ₂ and S 'between ₁ to S ₂₎ is increased gradually, significant more than in the case of D / L <0.5 If D / L exceeds 0.5 The rate of increase is steep and the maximum bending stress index increases. Then, when D / L becomes 1.0, the corrugated strip joins with the flat plate liner and extends to the bottom surface level of the composite corrugated body at an arbitrary position in the y-direction cross section.
Compared with the case of 5 ≦ D / L <1.0, the transition to the third truss structure is suddenly made again, and the out-of-plane bending strength is further increased. And
As the D / L increases beyond 1.0, the number of places where the corrugated strip joins the flat plate liner and the number of places where it extends to the bottom of the composite corrugated body increases, so the rate of increase is greater than when D / L <0.5. As a result, the gradient becomes steeper and the maximum bending stress index increases.

As is clear from the graph of FIG. 4, the preferable range for obtaining a large out-of-plane bending strength is D / L ≧ 0.5, and the most preferable range is D / L ≧ 1.0. And
As described above, since the amplitude ratio H / L is 0.2 or more in a preferable range, the preferable range of the present invention that satisfies both is D / L ≧ 0.
It can be said that it is within the range indicated by the diagonal lines of 5, H / L> 0.2.

Next, the meandering ratio D / which is the third element that defines the shape of the corrugated row 13 that constitutes the corrugated core body 11 according to the present invention.
Looking at N, this meandering ratio shows the relationship between the amplitude D and the wavelength N when each corrugated strip is viewed in a plane.
As is clear from FIG. 5, the corrugated strip meanders deeper (larger) as D / N increases when N is constant.

Here, regarding each of the corrugated strips (A) to (D), regarding the angle α formed by the horizontal line in the y direction at the maximum inclination position of the meandering wave, α increases as D / N increases. In, the component in the x direction gradually increases. This means that the larger the D / N, the greater the strength, which corresponds to the bending stress in the direction orthogonal to the x direction. In practice, if D / N> 0.15, D / L ≧ 0.5 A large maximum bending strength can be obtained.
When this relationship is shown in the graph of FIG. 6, the curved portion shown by the diagonal lines is a suitable meandering ratio D / N of the corrugated core body 11 of the present invention.
It can be said that the meandering polymerization rate is within the range of D / L.

For the above reasons, the corrugated core used in the present invention preferably has an amplitude rate H / L> 0.2, a meandering polymerization rate D / L ≧ 0.5,
By setting the meandering ratio D / N> 0.15, more preferably H / L> 0.
2, D / L ≧ 1.0, D / N> 0.15.

Next, the single-sided reinforced composite corrugated body (H / L = 0.5, D / L = 1.0, D / N = 0.3) according to the present invention obtained as described above is shown in FIG. Single-sided cardboard (H / L = 0.5)
Was compared with the strength.

Table 1 shows the in-plane compressive strength test results.

As is clear from Table 1, when comparing the composite corrugated body used in the present invention with the conventional single-sided cardboard,
The in-plane compressive strengths in the y direction are almost the same, but it is clear that in the x direction, the composite corrugated body has about 3 times the strength as compared with the conventional one.

Table 2 shows the results of the out-of-plane compressive strength test. From this table, the single-sided reinforced composite corrugated body used in the present invention has an out-of-plane compressive strength of about 1.7 times that of the conventional single-sided cardboard. It is clear.

Table 3 shows the test results of the out-of-plane bending strength in the plane direction perpendicular to the x direction in FIGS. 1 and 10, and from this table, the single-sided reinforced composite corrugated body according to the present invention is It is clear that it has an extremely high flexural strength of about 20 times that of cardboard.

As described above, it can be said that the single-sided reinforced composite corrugated body used in the present invention is significantly superior to the conventional single-sided cardboard in various structural strength performances.

As described above, the single-sided reinforced composite corrugated body having many excellent properties is cut into a predetermined shape and bent to obtain the assembled case according to the present invention.

FIG. 7 (A) shows a deployable sheet 15 for obtaining the assembled case according to the first embodiment of the present invention. In this deployable sheet 15, the corrugated rows 13 meander in a lateral direction. A plate liner material 12 is bonded to one surface of the corrugated core body 11 so that the corrugated core body 11 is located on the inner surface of the case that is disposed in the box. And in this unfolding sheet 15, four horizontally long rectangular sections II, IV, which are continuous in the horizontal direction,
A ruled line 14 defining V and VI is formed, and an upper flap I and a lower flap III that can be independently bent are formed above and below the upper and lower ruled lines of each horizontally long rectangular section. In the illustrated example, the margin 16 is formed on the side edge of the horizontally long rectangular section V at the left side end. And when this unfolded sheet is sent to the automatic box making machine, it is folded along the ruled line 14,
The glue margin 16 is adhered to the horizontally long rectangular section II on the right side end, and then the four lower flaps III are sequentially folded and joined by the fasteners (not shown), as shown in FIG. 7 (B). A so-called A type assembly type case 17 as shown is obtained.

FIG. 8 (A) shows a developing sheet 15a for obtaining an assembled case according to the second embodiment of the present invention. In this unfolding sheet, the longitudinal direction of the corrugated row 13 extends in the longitudinal direction of the unfolding sheet 15a, and other configurations are the same as in the case of the first embodiment.

In the above-mentioned first and second embodiments, the flat plate liner material 12 is adhered so as to be located on the outer surface of the box-formed case, but this is taken into consideration in consideration of convenience when printing on the surface. Therefore, the flat plate liner material may be located on the inner surface if necessary.

Further, in the above-described embodiment, only the case where the corrugated row extends along the longitudinal direction or the lateral direction of the expansion sheet has been described, but the corrugated row is inclined at an arbitrary angle with respect to the longitudinal direction of the expansion sheet. It may be formed or cut in the left state.

Next, the assembled case (7th embodiment) according to the first embodiment of the present invention.
Fig. (B)) and the conventional assembling type case (K180-SCP120) shown in Fig. 11 (B) in the vertical direction (I-III) of Fig. 7.
Direction) and the results are shown in Table 4.

As is apparent from the test results, when the present invention product and the conventional product are compared, the compressive strength in the I-III direction, that is, the vertical direction is 2.65 times greater in the case of the present invention product than in the case of the conventional product. It became a thing.

It is apparent that the out-of-plane compressive strength of each surface itself, that is, the cushioning performance, which is strongly required for the assembled case, is improved by about 1.7 times as compared with the conventional product as shown in Table 2 above. .

The material of the single-sided reinforced composite corrugated body according to the present invention is paper or a paper-based material, which is a simple composite of various papers or a laminated composite of various papers and films made of various non-paper-based substances. There are various other materials such as processed papers coated with, impregnated with or adhered to the body or various cellulose or non-cellulosic materials, and combinations of the above various materials are also effective in the present invention.

Further, in the above-mentioned embodiment, the case of the assembling type case using the single-sided reinforced composite corrugated body in which the flat plate liner is bonded to one side of the corrugated core has been described, but the double-sided reinforced composite in which the flat plate liner is bonded to both sides of the corrugated core is described. Even when forming an assembly type case using a corrugated body,
Compared with the case where the assembly type case is formed using the conventional double-sided corrugated cardboard, excellent effects are exhibited in the same relative relationship as the relationship between the single-sided cardboard and the single-sided reinforced composite corrugated body in the above-mentioned embodiment.

<< Effect >> As described above, the assembling type case according to the present invention forms the corrugated rows by alternately providing the peaks and the valleys in the vertical direction, and corrugated cores formed by meandering the corrugated rows in a plane. Since the corrugated core itself has excellent in-plane compressive strength, vertical out-of-plane compressive strength and out-of-plane bending strength, the assembled case manufactured has a large compressive strength in the front and rear and left and right. However, the cushioning property of protecting the contents against external impact is excellent, and since the flap piece at the opening has a large bending strength, it is sufficiently protected against bending, bending, breakage and the like.

In particular, the single-sided reinforced composite corrugated body used in the present invention has an in-plane compressive strength in the x direction that is extremely larger than that of a conventional single-sided cardboard, and has a strength equal to or greater than the in-plane compressive strength in the y direction. It is possible to cut a corrugated row in any direction to obtain a spread sheet, and to fabricate a prefabricated case having sufficient strength in all surface directions.

The fact that the corrugated striations can be cut in any direction means that a single-sided reinforced composite corrugated body is continuously manufactured with the maximum economical width, and the expansion sheet body is vertically and horizontally combined within the maximum width. Therefore, it is possible to cut so as to obtain the minimum scrap, and the width efficiency is improved, and as a result, high productivity can be obtained.

Further, since the core material that constitutes the conventional assembling type case is formed by forming the straight corrugated strips in parallel only in one direction (y direction), warp deformation easily occurs in the state of the deployable sheet, Although it tends to cause a failure in the automatic box making machine, in the case of the assembling type case of the present invention, corrugations are formed in the x direction and the y direction of the corrugated core body,
No warp deformation occurs even in the state of the expandable sheet, and no shape distortion occurs in the case body after box making.

In addition, since the core material and the flat plate liner material that constitute the conventional assembling type case are bonded in parallel straight lines, the bonding density is low, and the striped uneven surface is formed by the bonding portion and the non-bonding portion. It was easy to form and printability was poor. On the other hand, in the case of the assembling type case of the present invention, since the bonding between the corrugated core body and the flat sheet material is on a meandering parallel curve, the bonding density is increased and warp deformation is prevented. It prevents the occurrence of such striped uneven surface, maintains the flatness of each surface of the case, and
Precision printing suitability for S-bar etc. is greatly improved.

Further, in the present invention, since the bonding portion between the corrugated core body and the flat plate liner material is on a meandering curve, when a ruled line is provided along the longitudinal direction of the corrugated row, this ruled line is often the above-mentioned bonded line. Since it passes through the joint part intermittently, the ruled line can be bent surely and precisely. In particular, the meandering polymerization rate
When D / L ≧ 1, even if the ruled line is provided at any position, the ruled line is bent more precisely because it always intersects with the corrugated row at a plurality of positions.

[Brief description of drawings]

FIG. 1 is a partial perspective view showing the flat plate liner material of the composite corrugated body used in the present invention by partially breaking it, and FIG.
(F) is a cross-sectional shape of a corrugated strip that constitutes a composite corrugated body, showing the relationship between its wavelength and its wave height.
FIGS. 4 (A) to 4 (E) are diagrams showing the positional relationship between corrugated strips and the positional relationship between the corrugated strips and the flat liner material at different meandering polymerization rates of the corrugated strips constituting the composite corrugated body, FIG. Is a graph showing the relationship between the meandering polymerization rate, the amplitude rate, and the out-of-plane maximum bending strength index, FIG.
(F) is a diagram showing different meandering rates of corrugated strips constituting the composite corrugated body, FIG. 6 is a graph showing the relationship between the meandering polymerization rate, the amplitude rate and the out-of-plane maximum bending strength index, FIG. 7 (A). ) And (B) are respectively a development sheet diagram and a box-making diagram of the assembling type case according to the first embodiment of the present invention.
9 (A) and 9 (B) are respectively a development sheet diagram and a box-making diagram of an assembling type case according to a second embodiment of the present invention.
FIG. 10 is a partial perspective view showing a conventional single-sided cardboard flat cardboard paper partially broken, and FIGS. 10A to 10C are a development sheet diagram and a box-making diagram of a conventional assembling type case, respectively. 10 …… Composite corrugated body 11 …… Corrugated core body 12 …… Flat liner material 13 …… Corrugated strip 15 …… Deployment sheet 16 …… Assembled case M …… Top, V …… Valley bottom

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-1-8031 (JP, A) JP 54-23035 (JP, B2)

Claims (1)

[Claims] 1. A sheet material is alternately provided with vertical ridges and troughs to form corrugated rows, and the corrugated rows are meandered in a flat corrugated shape so that cross-sectional waves of each corrugated row are formed. The amplitude ratio H / L (L: wavelength, H: amplitude) is 0.2 or more, and the meandering polymerization rate between the corrugated rows in a planar shape
Set the D / L (D: amplitude of plane meandering wave) to 0.5 or more, and further set the meandering ratio D / N (N: wavelength of plane meandering wave) of each corrugated row in a planar shape to 0.15 or more, And forming a reinforced composite corrugated body by adhering a flat plate liner to at least one surface of the corrugated core body, and providing the composite corrugated body with ruled lines defining four rectangular sections continuous in the lateral direction in the developed view. , Upper and lower flap pieces that can be independently bent are formed above and below the upper and lower ruled lines of each rectangular section, and the margins on the side edges of the rectangular section at either one of the left and right side ends. Is formed, the rectangular section is folded along the ruled line, and the glue margin is adhered to the rectangular section at the other side end so that the upper flap piece can be opened and closed to make a box. Assembled case.