JP3081702U - Foam resin cushioning member - Google Patents

Abstract

(57) Abstract: A foamed resin cushioning member having various rigidities and energy absorption rates is obtained from a minimum number of foamed resin sheets having different thicknesses. SOLUTION: A plurality of foamed resin sheets having different thicknesses formed by including a large number of bubbles in a synthetic resin are selectively laminated, and the laminated surfaces are bonded by heat welding.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 2. Description of the Related Art Conventionally, for example, products such as electric devices (hereinafter simply referred to as products) that are produced in factories and transported to stores or the like have been stored in boxes such as cardboard to facilitate transporting operations. In order to prevent the product from being damaged by an impact or the like generated during transportation, a foamed resin sheet containing a large number of air bubbles in a synthetic resin is provided between the box and the product. Is inserted. The present invention relates to an improvement of the foamed resin cushioning member.

[0002]

[Prior art]

 However, since there are so many types of the products, the shapes and weights of the products are various, and since they are various from precise ones to rugged ones, the allowable impact load during transportation is limited. The size also varies significantly between individual products. On the other hand, in order to improve the transportation efficiency, it is necessary to minimize the volume of the box housing the product.

Therefore, the foamed resin cushioning member is given to the box body during transportation with a deformation within a range in which a gap between a box body such as a cardboard and a product housed in the box body is allowed. It is required that the impact value be buffered to an impact value that the product can withstand. In addition, since the foamed resin cushioning member is basically discarded once used, it is necessary to minimize the volume from the viewpoint of resource saving and cost reduction.

In order to satisfy this requirement, a material having a large energy absorption amount per unit volume (hereinafter referred to as an energy absorption rate) is formed so that the required energy can be absorbed by the deformation within the allowable thickness range. Is secured. On the other hand, materials with a high energy absorption rate have high rigidity and a large amount of force transmission per unit deformation, so for products with a small allowable impact load, a material with a lower energy absorption rate, that is, a material with a low rigidity, must be selected. Materials are selected so as to satisfy the two contradictory conditions that must be met.

[0005]

[Problems to be solved by the invention]

 Conventionally, a foamed resin cushioning member is designed from a foamed resin sheet of a predetermined thickness by selecting a material with an energy absorption rate determined by the properties of the raw material and the foaming rate, and design-determining the thickness and shape. It has been used as a foamed resin cushioning member which has a desired impact absorption capacity by cutting and molding and satisfies the allowable impact value of the product. As a result, foamed resin sheets of the same material but different thicknesses, foamed resin sheets of different foaming ratios, foamed sheets of different materials and various types of sheets are required. Because the cushioning member is designed. Not only is it difficult to manage the foamed resin sheet, but also in such a variety of products, the amount is limited, making it difficult to respond to requests for reduction in manufacturing costs.

[0006] In such a situation, the present inventor has studied various types of foamed resin cushioning members, and as a result, although it is an extremely general rule, a product to be packaged with a large size needs more energy. It is necessary to absorb it, and the allowable value of impact resistance is relatively large due to its own weight. For example, when five foam resin sheets having skin layers on both sides with a thickness of 3 mm are laminated, there are two When three foamed resin sheets with skin layers were stacked and made the same thickness, the energy absorption amount was smaller in the latter case, but the amount of force transmitted to the product could be reduced to a cushioning member. Applying the above general rules to this, it is possible to prepare almost all foamed resin cushioning materials by preparing three to four types of foamed resin sheets of the same material and the same foaming rate and thickness. confirmed.

Here, the rigidity is defined as P / δ, where δ is a unit length mm when a force p (kg) is applied to the foamed resin cushioning member and δ is a deformation amount mm (strain) per unit area mm ^2. It can be expressed as In addition, the force applied from the outside to the product housed in the box body such as the cardboard via the foamed resin cushioning member is transmitted by the force absorbed by the foamed resin cushioning member. Therefore, the energy absorption rate of the foamed resin cushioning member is represented by a ratio of a force applied from the box to the foamed resin cushioning member and a force transmitted to the product via the foamed resin cushioning member. Amount.

[0008]

[Means for Solving the Problems]

 That is, in order to solve the above problems, the first means of the present invention corresponds to claim 1, and a foamed resin sheet formed by laminating a plurality of foamed resin sheets formed by including a large number of bubbles in a synthetic resin. In the resin cushioning member, the laminating surface of the foamed resin sheet is bonded by heat welding.

According to the first means of the present invention, when laminating a plurality of materials of the same material and having the same foaming rate and bonding them together, the bonding surface can be formed on a surface stronger than the foamed portion, and thus the foaming can be achieved. Since it is possible to give a higher energy absorption rate than that made of the resin buffer itself, there is an effect that it can be replaced with a foaming material of a harder material or a material having a lower foaming rate than those conventionally used.

The second means of the present invention corresponds to claim 2, wherein the plurality of laminated foamed resin sheets have the same or different plate thicknesses.

According to the second means of the present invention, there is an effect that the energy absorption rate can be selected within a predetermined range by appropriately selecting the plate thickness while maintaining the same lamination thickness.

The third means of the present invention corresponds to claim 3, wherein the lamination surface of the plurality of foamed resin sheets is cured by heating to form a skin layer.

According to the third means of the present invention, there is an effect that the skin layer can be reliably formed on the bonding surface, and the first means and the second means of the present invention can be reliably established. .

[0014]

[Embodiment of the invention]

 The synthetic resin used as the foamed resin sheet in the present invention is a synthetic resin having thermoplasticity, such as polypropylene, manufactured by a well-known mechanical or chemical foaming technique. The laminated surface of the foamed resin sheet is formed by bonding by heat welding. The foamed resin cushioning member of the present invention is cut into various shapes by a cutting machine such as a press machine and inserted between the cardboard and the product. Being used.

[0015]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing one embodiment of the present invention. In this embodiment, a foamed resin cushioning member 1a is formed by laminating two foamed resin sheets 2a and 2b, and a lamination surface 3a thereof will be described later. Bonded by heat welding. The thickness ta of each of the two foamed resin sheets 2a and 2b is larger than tb.

FIG. 2 is a schematic view for explaining a method of manufacturing the foamed resin cushioning member 1a. In this figure, reference numerals 4a and 4b denote winding frames around which foamed resin sheets 2a and 2b are wound, respectively. 5a and 5b are pressurizing rollers, 6 is a heated hot air blower equipped with hot air jets 6a and 6b, and 7 is a reel around which the foamed resin buffer member 1a is wound.

Therefore, the two foamed resin sheets 2 a, 2 b wound around the winding frames 4 a, 4 b, respectively, are welded to the laminated surface 3 a shown in FIG. It is heated at a suitable temperature (about 130 ° C. in the case where the synthetic resin forming the two foamed resin sheets 2a and 2b is, for example, polypropylene) and pressed by the pressure rollers 5a and 5b to adhere. Is done.

As described above, the foamed resin cushioning member 1 a to which the laminated surface 3 is bonded by heat welding is wound around the reel 7 as shown in the figure. The foamed resin cushioning member 1a wound around the winding frame 7 is used after being cut into an appropriate shape by a cutting machine (not shown) such as a press. FIGS. 3 and 4 show another embodiment. The foamed resin cushioning member 1b shown in FIG. 3 is composed of three foamed resin sheets 2a, 2b, 2c with respective plate thicknesses ta, tb, tc. Are laminated, and the laminated surfaces 3a and 3b are bonded by heat welding.

The foamed resin cushioning member 1c shown in FIG. 4 is formed by laminating a foamed resin sheet 2d in which the thickness td of the foamed resin sheet 2d is smaller than the thickness ta of the foamed resin sheet 2a. Bonded by welding.

As described above, the embodiment of the present invention has been described in which two or three foamed resin sheets are laminated. However, the present invention is not limited to this. Thus, it is possible to extremely easily manufacture a foamed resin cushioning member having a plate thickness that exactly matches the gap between a product such as a cardboard box and a product without any gap. Further, a thin sheet-like skin layer melted by heating is formed on the laminating surface of the plurality of laminated foamed resin sheets, whereby the rigidity suitable for a cushioning member can be enhanced.

[0021]

[Effect of the invention]

 As is clear from the above description, the foamed resin cushioning member of the present invention has a simple structure in which the laminated surface of the foamed resin sheet is bonded by heat welding, and a foamed resin sheet having a large thickness as in the past is prepared. It is possible to prepare a foamed resin cushioning member that fits exactly into the gap between the product such as a cardboard box and the product without any gap.

Further, the foamed resin cushioning member of the present invention does not use an adhesive, so that the manufacturing operation is easy, and thus the manufacturing cost can be significantly reduced. In addition, a skin layer cured by heating is formed on the laminating surface of the foamed resin sheet, thereby improving rigidity suitable as a cushioning member.

[Brief description of the drawings]

FIG. 1 is a perspective view of a foamed resin cushioning member according to an embodiment of the present invention.

FIG. 2 is a schematic view illustrating a method of manufacturing a foamed resin cushioning member according to an embodiment of the present invention.

FIG. 3 is a perspective view of a foamed resin cushioning member according to another embodiment of the present invention.

FIG. 4 is a perspective view of a foamed resin cushioning member according to another embodiment of the present invention.

[Explanation of symbols]

 1a, 1b, 1c Foamed resin sheet 2a, 2b, 2c, 2d Foamed resin sheet 3a, 3b Laminated surface 4a, 4b Foamed resin sheet frame 5a, 5b Pressure roller 6 Heated hot air blower 6a, 6b Hot air jet 7 Reaming frame of foamed resin cushioning member

Claims (3)

[Utility model registration claims] 1. A foamed resin cushioning member formed by laminating a plurality of foamed resin sheets formed by including a large number of air bubbles in a synthetic resin, wherein the laminated surfaces of the foamed resin sheets are bonded by heat welding. A foamed resin cushioning member characterized by the above-mentioned. 2. The foamed resin cushioning member according to claim 1, wherein the plurality of laminated foamed resin sheets have the same or different thicknesses. 3. The foamed resin according to claim 1, wherein a laminating surface of the plurality of foamed resin sheets has a thin sheet-like skin layer melted by heating. Cushioning member.