JP7750753B2 - Foldable air bed - Google Patents

Description

Application of Article 30, Paragraph 2 of the Patent Act (1) October 20, 2021 to October 22, 2021 (Exhibition date: October 21, 2021 to October 22, 2021) Crisis Management Industry Exhibition 2021, Tokyo Big Sight Aomi Exhibition Building (1-4 Aomi, Koto-ku, Tokyo) Announced from October 21, 2021 to October 22, 2021 at the Crisis Management Industry Exhibition 2021 held from October 20, 2021 to October 22, 2021

The present invention relates to a foldable air bed.

BACKGROUND ART Conventionally, as simple beds for use in leisure activities or for use in disasters and evacuation, collapsible or foldable types have been proposed.
For example, Patent Document 1 discloses a portable camping bed, which includes an air mattress to be attached to a support base, and describes a simple bed that can be used by assembling the support rods and leg rods that make up the support base to the air mattress.

Patent Document 2 also discloses a folding bed. The folding bed is configured by interconnecting the support and the sheet, which are provided with a support body having a number of support rods and an insertion bag into which part of the support body is inserted. The document also shows an embodiment in which the support body and the sheet can be folded while still interconnected.

Jitsuto No. 963320 Jitsuto No. 3028453

However, the above-mentioned conventional techniques have the following problems.
That is, the portable camping bed disclosed in Patent Document 1 requires assembly work when in use and disassembly work when storing, which is time-consuming and labor-intensive. In addition, in order to store the disassembled portable camping bed compactly, the air inside the air mattress needs to be vented, which is troublesome work.

On the other hand, the folding bed disclosed in Patent Document 2 is constructed by interconnecting a support and a sheet, and can be used simply by unfolding the support. Therefore, while the folding bed does not require assembly or disassembly when in use or for storage, because the surface on which the user lies is constructed from a single sheet, there is a problem that it is poor at distributing body pressure in localized areas such as the back of the head and lower back, making it difficult to provide a comfortable sleep. Furthermore, when lying on a single sheet, cold air is easily transmitted from the space below the sheet and from the floor, creating the problem of feeling cold when used at night or in winter.

The present invention was made in consideration of the above-mentioned problems. Specifically, the object of the present invention is to provide a simple bed that shortens the time and effort required when using and storing the bed, is comfortable to sleep on, and is less susceptible to cold air from the space below the bed surface or the floor.

The foldable air bed of the present invention comprises an air mattress section having an upper surface, a lower surface, an air layer between the upper surface and the lower surface, and a ventilation section that allows ventilation between the air layer and the outside, and legs for supporting the air mattress section, wherein the air mattress section comprises side materials and a cushion body contained in the side materials, the cushion body being made of a foamed resin molded body having a thickness of 2 cm to 5 cm, the legs being made up of a plurality of rib members and can be folded together, and can be changed between a closed state in which the legs are folded and the air mattress section is positioned between the opposing rib members, and an open state in which the legs are unfolded and the air mattress section is unfolded, and is characterized in that the volume of the air mattress section in the closed state is smaller than the volume of the air mattress section in the open state.

The foldable air bed of the present invention, with the above-described configuration, can be easily switched between a closed state in which the legs are folded, thereby placing the air mattress between the opposing rib members, and an open state in which the legs are unfolded, thereby unfolding the air mattress. Therefore, the foldable air bed of the present invention can reduce the time and effort required for use and storage. Furthermore, because the surface on which the user lies is made up of the air mattress, the present invention provides a comfortable sleeping surface and excellent heat retention.

1 is a perspective view of a foldable air bed according to a first embodiment of the present invention in an open state; FIG. 1 is a perspective view of a foldable air bed according to a first embodiment of the present invention in a closed state; FIG. 3 is a cross-sectional view of the air mattress portion of the foldable air bed shown in FIG. 1 taken along line III-III. FIG. 10 is a perspective view of a fourth embodiment of a folding air bed of the present invention in an open state.

[First embodiment]
A first embodiment of a foldable air bed of the present invention will be described below with reference to Figures 1 to 3. In all the drawings, similar components are given the same reference numerals, and duplicated descriptions will be omitted where appropriate.
Fig. 1 is a perspective view of a foldable air bed 100 according to a first embodiment of the present invention in an open state. Fig. 2 is a perspective view of the foldable air bed 100 according to a first embodiment of the present invention in a closed state. Fig. 3 is a cross-sectional view of the air mattress part 10 of the foldable air bed 100 shown in Fig. 1 taken along III-III.
In the present invention, the "open state" refers to a state in which the legs 30 are spread out, thereby spreading out the air mattress unit 10 so that it can be used as a bed. On the other hand, the "closed state" refers to a state in which the legs 30 are folded up and the air mattress unit 10 is placed between the opposing rib members 32, 32, making it suitable for storage, transportation, etc. Note that in the present invention, "the air mattress unit 10 is placed between the opposing rib members 32, 32 or the outer edge support members 40, 40" means that at least a portion of the air mattress unit is placed between the rib members 32, 32 or the outer edge support members 40, 40 that face each other in the closed state, and also includes a state in which a portion of the air mattress unit protrudes outward from between the rib members 32, 32 or the outer edge support members 40.
In the present invention, an air bed refers to a structure comprising an air mattress section having an upper surface, a lower surface, an air layer between the upper and lower surfaces, and a ventilation section that allows ventilation between the air layer and the outside. Here, the ventilation section may be, for example, a vent hole attached to the side material that constitutes the air mattress section, or the ventilation section may be a breathable side material that constitutes at least a part of the upper and/or lower surface. In other words, the present invention encompasses both an embodiment in which the upper and/or lower surface that constitutes the air mattress section is made of a breathable material, and an embodiment in which the upper and/or lower surface is made of a non-breathable material with ventilation holes.

As shown in Figures 1 to 3, the foldable air bed 100 is comprised of an air mattress portion 10 and legs 30, and is a simple foldable bed that can be folded into a closed state as shown in Figure 2, or unfolded into an open state as shown in Figure 1.

(Air mattress section)
The air mattress unit 10 has an upper surface 12 and a lower surface 14, with an air layer 20 between the upper surface 12 and the lower surface 14. The air layer 20 and the outside of the air mattress unit 10 are configured to be ventilated by a ventilation section 16. More specifically, the air mattress unit 10 includes a hollow, bag-shaped side material 11 having an upper surface 12 and a lower surface 14, with the interior of the side material 11 constituting the air layer 20. The upper surface 12 forms the sleeping surface for the user in the open state. The air mattress unit 10 is provided with a ventilation section 16 to allow ventilation between the inside and outside of the air mattress unit 10, which allows a significant thickness of the air layer 20 to be created inside the air mattress unit 10 in the open state, and allows at least a portion of the air inside the air mattress unit 10 to be discharged in the closed state, thereby reducing the volume of the air mattress unit 10.

In this embodiment, the ventilation sections 16 are provided as air vents 18 that penetrate the thickness direction of the side material 11 that constitutes the air mattress section 10 and are provided at appropriate locations on the air mattress section 10. In the foldable air bed 100, which is rectangular when viewed from above, the air vents 18 are provided on each of the opposing short sides of the air mattress section 10, as shown in Figure 1, to facilitate the flow of air into and out of the rectangular air mattress section 10. However, the locations and number of the air vents 18 are not limited to this. For example, the air vents 18 may also be provided near the center of the underside 14.

Furthermore, the ventilation section 16 of the present invention is not limited to the ventilation hole 18 described above. For example, as in the second embodiment described below, if the air mattress section 10 is constructed using a breathable side member made of a breathable material, the breathable member itself can serve as the ventilation section 16.

In this embodiment, the side material 11 constituting the air mattress portion 10 is a non-breathable side material made of a non-breathable material, and the air mattress portion 10 is provided with a cushion body 50 enclosed within this non-breathable side material (side material 11).
The material constituting the non-breathable side material (side material 11) can be appropriately selected from sheet-like materials that are gas impermeable both inside and outside the air mattress portion 10, and examples include synthetic leather, artificial leather, resin sheets, and resin composites formed by laminating a resin sheet (resin layer) onto fabric. When the side material 11 is made of a non-breathable material, it is preferable to provide ventilation holes 18 as the ventilation portion 16, as described above.

The cushion body 50 can be appropriately selected from among elastically deformable members with cushioning properties that can secure the air layer 20 inside the air mattress portion 10. For example, materials that constitute the cushion body 50 include foamed resin molded bodies and foamed resin beads. Foamed resin molded bodies have air bubbles inside, so when enclosed in the side material 11, the foamed resin molded bodies themselves can constitute the air layer 20. On the other hand, foamed resin beads contain air inside the beads and also have air between the beads, so the air layer 20 can be constituted by a group of foamed resin beads.
Examples of resins constituting the foamed resin molded body and foamed resin beads described above include urethane resins and polyolefin-based resins. Among these, urethane foam is preferred for the cushion body 50 because it exhibits moderate resilience and good cushioning properties when open, and is easy to fold when closed. Furthermore, the foamed resin molded body used as the cushion body 50 in the present invention preferably has some or all of its internal cells in an open-cell structure, and urethane foam with an open-cell structure is more preferred. Here, the open-cell structure refers to adjacent cells in the foamed resin molded body being connected to each other so that they can breathe.
The apparent density of the urethane foam is not limited, but from the viewpoint of achieving a good balance between cushioning properties and foldability, it is preferably 10 kg/ ^m3 or more, more preferably 12 kg/ ^m3 or more, and is preferably 70 kg/ ^m3 or less.

The thickness of the foamed resin molded cushion body 50 is not particularly limited, but from the perspective of providing good sleeping comfort and heat retention, it is preferably 1 cm or more, and more preferably 2 cm or more. From the perspective of ease of folding and compactness for storage, it is preferably 6 cm or less, and more preferably 5 cm or less. It is preferable that the height dimension of the side material 11 be equal to or greater than the thickness dimension of the cushion body 50; in this case, the thickness of the foamed resin molded cushion body 50 will be equal to the thickness of the air layer 20 in the open state.

As described above, the air mattress portion 10, which contains the cushion body 50 inside, has good cushioning properties and is excellent at dispersing body pressure in localized areas where weight is likely to be applied, such as the back of the head and lower back, providing a comfortable sleep.In addition, the air layer 20 prevents cold air from the space below the air mattress portion 10 or the floor from reaching the user, making it suitable not only for leisure activities but also for use in evacuation shelters, for example.

Furthermore, when the cushion body 50 is made of a foamed resin molded body, the following additional excellent effect is achieved. Specifically, foamed resin molded bodies exhibit self-restoring properties, whereby the internal air bubbles are crushed when external pressure is applied, reducing their apparent volume, and then returning to their original shape when the external pressure is released. Therefore, by changing the state from the open state shown in Figure 1 to the closed state shown in Figure 2 while the air vents 18 are open, the cushion body 50 made of foamed resin molded body is compressed by the rib members 32, making it possible to reduce the volume of the air mattress section 10 without any special air exhaust work. Furthermore, by changing the state from the closed state shown in Figure 2 to the open state shown in Figure 1 while the air vents 18 are open, the self-expanding properties of the foamed resin molded body cause the side material 11 to expand from the inside, and air flows into the interior through the air vents 18, without any special air supply work, providing the air mattress section 10 in a state suitable for use.

The air vents 18 may always be open, but may also be sealed with a sealing plug (not shown) as appropriate, for example, to maintain a good state after closing, or to maintain a sufficient thickness of the air layer 20 when a user lies on the upper surface 12 in the open state. This sealing plug ensures the cushioning properties of not only the cushion body 50 but also the air mattress portion 10 itself.

In this embodiment, the air mattress section 10 has the internal space of the side material 11 partitioned lengthwise into multiple partitioned regions 52, and each partitioned region 52 contains a cushioning body 50 that fits exactly within the dimensions of its respective internal space. Adjacent partitioned regions 52, 52 are partitioned by a bonding portion 64 that extends widthwise of the air mattress section 10. The bonding portion 64 is formed by joining the upper surface 12 and the lower surface 14 by any means such as fusion, adhesion, or sewing. Note that when the bonding portion 64 is formed by means such as fusion or adhesion, it is preferable to leave a through-hole 66 alongside the bonding portion 64 rather than completely partitioning the partitioned regions 52, 52 to allow ventilation between adjacent partitioned regions 52, 52.

As a variation of this embodiment, the present invention includes an embodiment in which the internal space of the air mattress portion 10 is not partitioned in any way, and the cushion body 50 contained within the side material 11 is made of a continuous foamed resin molded body. This embodiment will be described below as the fourth embodiment.

The air mattress unit 10 is configured to be approximately parallel to the surface on which it is placed when open, but as shown in Figures 1 and 3, for example, one end of the air mattress unit 10 in the longitudinal direction (the end on the left side of the paper in Figures 1 and 3) may be tilted slightly upward so that the user's head fits comfortably when lying down, even without a pillow.

(Sleeping comfort evaluation)
The sleeping comfort of the foldable air bed 100 equipped with the air mattress section 10 can be evaluated by the user's sensory evaluation as well as, for example, head pressure measurement as described below.
First, a pressure sensor mat is placed in the area of the foldable air bed 100 that comes into contact with the head when the bed is in the open position. An adult weighing approximately 60 kg lies supine on the mat, and the maximum pressure on the head is measured. The smaller the maximum pressure value, the better the pressure dispersion and the better the sleeping comfort. An example of such a pressure sensor mat is XSENSOR (USA registered trademark) manufactured by X Sensor Technology.
In the present invention, the range of maximum head pressure is not particularly limited, taking into consideration the influence of the subject's physique and weight, but from the perspective of providing a bed that is more comfortable to sleep on, the maximum head pressure is preferably 100N or less, more preferably 80N or less, even more preferably 70N or less, and particularly preferably 60N or less.

(leg)
Next, the legs 30 will be described. The legs 30 are configured to support the air mattress unit 10. In particular, in the open state, the legs 30 are required to support the air mattress unit 10 while the user is lying on the upper surface 12. When the foldable air bed 100 is changed between the open state and the closed state, the legs 30 and the air mattress unit 10 are deformed in unison, so the air mattress unit 10 is attached directly or indirectly to the legs 30.
In relation to the present invention, the phrase "the air mattress section 10 is indirectly attached to the leg section 30" refers to a state in which the air mattress section 10 is attached and supported by another support member (outer edge support member 40) connected to the leg section 30, as in this embodiment, and the phrase "the air mattress section 10 is directly attached to the leg section 30" refers to a state in which the air mattress section 10 is attached, fixed, and supported directly to the leg section 30 consisting of the rib member 32 (not shown).

The rib members 32 that make up the leg section 30 are made of materials strong enough to support the air mattress section 10. Examples of rib members 32 include long members made of metal or resin, and hollow tubular rib members 32 are preferred from the perspective of reducing weight.

The leg portion 30 is composed of a plurality of bone members 32, which can be folded together without being disassembled.
In this embodiment, the leg section 30 includes a plurality of first rib members 321 extending vertically from the floor surface, second rib members 322, 322 that intersect with each other when the long sides of the air mattress section 10 are viewed from the front, and third rib members 323 that intersect with each other when the short sides of the air mattress section 10 are viewed from the front. Each rib member 32 is connected to each of the other rib members 32 by connecting members. The term "connected" here does not mean that the relative positions of the connected rib members 32 are fixed, but rather means that the relative positions of the connected rib members 32 can be changed when force is applied.
For example, as shown in Fig. 1, a first rib member 321 and two intersecting second rib members 322 are connected by connecting members 34, and when force is applied, they slide on the connecting members 34, changing their relative positional relationship and enabling them to change to the closed state shown in Fig. 2. Similarly, the lower ends of the second rib member 322 and the third rib member 333 are connected by connecting members 35, and their relative positional relationship can be changed between the open state and the closed state.

The leg portions 30 and the air mattress portion 10 described above may be directly or indirectly connected. In this embodiment, an outer edge support member 40 (described below) is provided on the outer edge of the air mattress portion 10, and the air mattress portion 10 and the leg portions 30 are indirectly connected via the outer edge support member 40.

(Outer edge support member)
The foldable air bed 100 of this embodiment is provided with outer edge support members 40 along the outer edge of the air mattress portion 10. By providing the outer edge support members 40, flexing of the air mattress portion 10 when the user lies on it in the open state is effectively suppressed. In this embodiment, long members are provided along the long sides of the air mattress portion 10, which is rectangular in top view. The long members can be made of materials similar to the rib members 32 described above.
In this embodiment, the outer edge support member 40 has four elongated members arranged along one long side, and the ends of each of the two vertically aligned elongated members are connected to the ends of the rib members 32 by connecting members 36, so that when the legs 30 are folded into the closed state, they form a W-shape as shown in Figure 2. The same is true for the other long side.

In this embodiment, a tunnel-shaped loop portion 62 is provided along the outer edge of the long side of the air mattress portion 10, and the outer edge support member 40 is attached to the air mattress portion 10 by passing the outer edge support member 40 through this loop portion 62. The loop portion 62 may be formed integrally with the air mattress portion 10 by folding back the end of the outer edge of the long side of the side material constituting the air mattress portion 10 and securing this end to the air mattress portion 10 itself at a predetermined position using an appropriate securing means. Alternatively, the loop portion 62 may be created separately from the air mattress portion 10 and secured to the outer edge of the long side of the air mattress portion 10 using an appropriate securing means, thereby providing a post-installation. The securing means may be any means that provides sufficient bonding strength to support the air mattress portion 10 with the outer edge support member 40, such as sewing, adhesive bonding, welding, or other joining means, or joining members such as hook-and-loop fasteners or hooks.

When the legs 30 are folded, the outer edge support members 40 are also folded in conjunction with each other, and the air mattress unit 10, which has the outer edge support members 40 on its outer edge, is also folded, so that the air mattress unit 10 is positioned between the opposing rib members 32, 32 and between the outer edge support members 40, 40, as shown in Figure 2. Note that in the present invention, if the outer edge support members 40 are not provided, the air mattress may be positioned only between the opposing rib members 32, 32 when the legs 30 are folded (not shown).
Here, "the rib members 32, 32 or the outer edge support members 40 facing each other" does not necessarily mean that they are adjacent to each other, but also means that they are facing each other in a positional relationship that allows them to be connected by a straight line when the legs are folded. More specifically, in this embodiment, multiple outer edge support members 40 are provided continuing from the rib members 32. The multiple outer edge support members 40 bend together with the legs 30 while forming valley folds, thereby folding the air mattress unit 10 into a closed state with the top surface 12 facing inward. As a result, the air mattress unit 10 is positioned between the opposing outer edge support members 40, 40 and/or between the opposing rib members 32, 32 (leg members 30, 30) and is compressed by these. Therefore, as the cushion body 50 contracts, air in the air layer 20 naturally flows out through the ventilation portion 16 (open ventilation holes 18) provided in the air mattress unit 10, reducing the volume of the air mattress unit 10.
In this way, by folding the legs 30, the foldable air bed 100 can exhaust the air inside the air mattress section 10 without any special exhaust work, and the volume of the air mattress section 10 in the closed state can be smaller than the volume of the air mattress section 10 in the open state.

Furthermore, as described above, by switching from the closed state to the open state, the cushion body 50 contained within the air mattress portion 10 self-inflates, allowing air to flow into the reduced-volume air mattress portion 10 without any special air supply work.

[Second embodiment]
A second embodiment of the present invention will now be described.
The present invention includes a second embodiment in which the air mattress portion comprises a breathable side material made of a breathable material and a cushion body enclosed in the breathable side material. This second embodiment is configured in the same manner as the foldable air bed 100 of the first embodiment described above, except that some or all of the components constituting the side material 11 are breathable side materials. Therefore, illustrations of the second embodiment will be omitted, and the description of the first embodiment should be referred to as appropriate for the configuration other than the breathable side material.

The material that makes up the breathable side material can be appropriately selected from materials that exhibit gas permeability both inside and outside the air mattress portion 10, such as woven fabrics and knitted fabrics. More specifically, canvas, which is a plain weave fabric woven from linen or cotton, and Oxford cloth, which is a basket weave, are preferred because they are strong and feel good against the skin. When the side material 11 is made from a breathable side material, the breathable side material itself becomes the ventilation portion 16.

In the second embodiment, the foldable air bed, like the first embodiment, has a cushion enclosed within the side material (breathable side material). Therefore, when the bed is changed from a closed state to an open state, the cushion self-inflates, pushing out the breathable side material, thereby ensuring a sufficient air layer inside the air mattress portion.

[Third embodiment]
A third embodiment of the present invention will now be described.
The present invention encompasses a third embodiment in which the air mattress portion includes a non-breathable side material made of a non-breathable material, and the non-breathable side material has ventilation holes as ventilation sections and a sealing plug that can be repeatedly attached and detached from the ventilation section. This third embodiment is configured similarly to the foldable air bed 100 of the first embodiment, except that no cushion body is housed inside the non-breathable side material (side material 11) and that a sealing plug is required to seal the ventilation section. Therefore, illustrations of the third embodiment will be omitted, and for the configuration other than the two differences 2 described above, please refer to the description of the first embodiment as appropriate.

In the third embodiment, when the foldable air bed is in the open position, sufficient air is artificially supplied to the air mattress section through the air vents, which are then sealed with a sealing plug, thereby maintaining the cushioning properties of the air mattress section. Furthermore, when changing from the open position to the closed position, the sealing plug is removed, leaving the air vents open, and the legs are folded up. This causes the air mattress section to be sandwiched between the opposing ribs or outer edge support members and compressed, naturally releasing the air inside and reducing its volume.

[Fourth embodiment]
A fourth embodiment of the present invention will be described below with reference to Fig. 4. Fig. 4 is a perspective view of a foldable air bed 100 according to the fourth embodiment of the present invention in an open state.
The foldable air bed 100 of the fourth embodiment differs from the foldable air bed 100 of the first embodiment in that the interior of the air mattress portion 10 is not partitioned but is a single space, and the cushion body 50 housed in the air mattress portion 10 is composed of a series of foamed resin molded bodies. In other respects, the foldable air bed 100 of the fourth embodiment is configured in the same way as the foldable air bed 100 of the first embodiment, so for similar configurations, please refer to the description of the first embodiment as appropriate.

The folding air bed 100 of the fourth embodiment has an easy-to-manufacture structure, and because the cushion body 50 is a continuous piece, it is more comfortable to lie on. Furthermore, the folding air bed 100 of the fourth embodiment has substantially the same configuration as the first embodiment, and exhibits the same excellent effects as the first embodiment described above.

As a modification of the fourth embodiment, the side material of the folding bed 100 of the fourth embodiment can be changed from non-breathable to breathable, and the ventilation holes 18 can be omitted as appropriate.

Although the first to fourth embodiments of the present invention have been described above, the above-described embodiments do not limit the present invention in any way. For example, the structure of the legs and the method of folding the legs are not limited to the above-described aspects.
As an example, by folding the legs in a direction that creates a valley fold in an area of approximately half the length of the air mattress portion, the air mattress portion can be positioned between the bone members that make up the legs or between the outer edge support members, and by compressing it, the air in the air layer can be easily expelled.
In addition, in order to maintain a good closed state, the outer periphery of the foldable air bed in the folded state may be restrained by a restraining means such as string or rubber, or a stopper may be provided that is arranged between one rib member and another rib member, one outer edge support member and another outer edge support member, or one rib member and one outer edge support member to fix the distance between them when the bed is folded.
In addition, in the present invention, the air mattress portion can be folded or unfolded in conjunction with the movement of the legs in the open and closed states, so they are normally kept connected. However, the air mattress portion may be configured to be detachable from the legs (or the outer edge support members) as needed for cleaning or replacement.

Example 1
An air mattress was prepared, with an internal space of 185 cm long, 50 cm wide, and 5 cm high, and consisting of a bag-shaped, non-breathable side material made of a resin composite (TPU composite) consisting of a polyester fabric with a urethane resin sheet bonded to one side. Legs and peripheral support members attached to the upper ends of the legs, similar to those shown in Figure 1, were also prepared. The peripheral support members were passed through loops on the outer edges of the long sides of the air mattress, indirectly connecting the air mattress and the legs. This foldable air bed was designated Example 1. Note that Example 1 corresponds to the third embodiment described above, and the distance from the floor to the underside of the air mattress was 38 cm.

Example 2
A foldable air bed was fabricated in the same manner as in Example 1, except that the dimensions of the internal space of the non-breathable side material were changed to the values shown in Table 1, and a urethane foam (apparent density: 16 kg/m ³ , 40% compression hardness: 50 N, resilience modulus of 19% or less, open-cell structure) measuring 180 cm in length, 50 cm in width, and 1 cm in thickness was placed inside the non-breathable side material as a cushion body, and this was designated Example 2. Note that Example 2 corresponds to the fourth embodiment described above.

(Examples 3 to 7)
Foldable air beds were prepared in the same manner as in Example 2, except that the dimensions of the internal space of the non-breathable side material and the dimensions of the urethane foam contained inside the non-breathable side material were changed to the values in Table 1, and these were designated Examples 3 to 7.

(Comparative Example 1)
A cot was fabricated in the same manner as in Example 1, except that a sheet (Oxford fabric, length 185 cm x width 50 cm) made by basket weaving cotton thread was used instead of the air mattress portion, and this was designated Comparative Example 1. The distance from the floor surface to the underside of the sheet was 38 cm.

Using the examples and comparative examples obtained as described above, sleeping comfort evaluation 1 (body sensation evaluation), sleeping comfort evaluation 2 (head pressure measurement), heat retention evaluation, and foldability evaluation were performed as follows, and the results are shown in Table 1.

(Sleeping comfort rating 1; subjective rating)
Ten monitors each lay on the bed in a supine position to check the comfort of the bed, and rated it as follows. The most common evaluation results are shown in the table below.
◎: There is almost no strain on the body and the sleeping comfort is very good.
Good: Moderate cushioning and comfortable to sleep on.
△: It feels a little hard, but not so hard that you feel like you're hitting the bottom.
×: Feels like hitting the bottom and is hard.

(Sleeping comfort rating 2: head pressure measurement)
A pressure sensor mat (XSENSOR (USA registered trademark), manufactured by X Sensor Technology, Inc.) was placed on the top surface of the bed so as to overlap the area where the head would come into contact. An adult weighing 60 kg lay on the mat, and the maximum pressure in the head area was measured.

In the sleeping comfort evaluation 1 described above, it was confirmed that the sleeping comfort of all the examples was improved compared to the comparative examples, and that excellent sleeping comfort was achieved by making the air layer of an appropriate thickness in particular.
Furthermore, in the sleeping comfort evaluation 2, it was confirmed that the maximum head pressure was significantly reduced in all of the examples compared to the comparative example 1. Furthermore, from the results of the sleeping comfort evaluations 1 and 2, it was confirmed that the smaller the numerical value of the maximum head pressure, the better the sleeping comfort.

(Heat retention evaluation)
In an environment with a room temperature of 23°C, a temperature sensor (Ondotori TR-72Ui, manufactured by T&D Corporation) was placed near the center of the top surface of a folding air bed. A 35 cm x 35 cm x 1 cm aluminum plate heated to a temperature of 50°C was placed so that it was in contact with the sensor part of the temperature sensor, and a blanket was quickly placed over the entire top surface of the bed. The temperature of the aluminum plate was measured and a temperature curve was obtained. The slope of the approximation equation for the sample temperature curve was calculated in the range from time T0, when the aluminum plate temperature was 40°C, to time T1, when the aluminum plate temperature was 30°C.
The same test as above was conducted except that Comparative Example 1 was used as a blank, and the slope of the approximation equation for the temperature curve of the blank was calculated in the same manner as above. Then, the heat retention rate was calculated from the following formula (1).
[Equation 1]
Heat retention rate (%) = (blank slope - sample slope) ÷ blank slope × 100 (1)
The heat retention rate calculated as described above was evaluated according to the following criteria.
◎: Heat retention rate is 50% or more.
Good: Heat retention rate is 40% or more and less than 50%.
△: Heat retention rate is 10% or more and less than 40%.
×: Heat retention rate is less than 10%.

The above heat retention evaluation confirmed that all of the Examples had improved heat retention compared to Comparative Example 1, in which the bed surface was made of a sheet. In particular, Examples 2 to 7, which had an air mattress portion with a urethane foam cushion inside the side material, were confirmed to exhibit excellent heat retention.

(Evaluation of foldability)
The volume V1 of the bed when it was folded and the volume V0 when the air mattress portion was removed from the bed and the legs and outer edge support members were folded were determined, and the ratio (V1/V0) of volumes V1 and V0 was confirmed and evaluated according to the following criteria: The volumes V1 and V0 were calculated using the following formula (2) by measuring the height T (cm) from the floor to the highest position when the bed was folded and placed on the floor (see Figure 2), the dimension W1 (cm) of the largest horizontal part observed when looking straight at the long side, and the dimension W2 (cm) of the largest horizontal part observed when looking straight at the short side.
[Equation 2]
Volume (cm ³ ) = Height T (cm) × Dimension W1 (cm) × Dimension W2 (cm) (2)
The ratio of the volumes V1 and V0 calculated as described above was evaluated according to the following criteria.
⊚: The ratio (V1/V0) is 1.2 or less.
◯: The ratio (V1/V0) is greater than 1.2 and is 3 or less.
△: The ratio (V1/V0) exceeds 3.

The above foldability evaluation confirmed that all of the examples with an open, significantly thick air mattress section could be folded compactly without any special ventilation work.

The present invention described above encompasses the following technical ideas.
(1) an air mattress part having an upper surface, a lower surface, an air layer between the upper surface and the lower surface, and a ventilation part that allows ventilation between the air layer and the outside;
and legs for supporting the air mattress portion,
The leg portion is composed of a plurality of bone members and is foldable as a unit;
a closed state in which the leg portions are folded and the air mattress portion is disposed between the opposing rib members;
an open state in which the leg portions are spread and the air mattress portion is spread;
can be changed to
A foldable air bed, characterized in that the volume of the air mattress portion in the closed state is smaller than the volume of the air mattress portion in the open state.
(2) An outer edge support member is provided along the outer edge of the air mattress portion,
The outer edge support member is connected to the leg portion, and the outer edge support member is folded in conjunction with the leg portion being folded, and
A foldable air bed as described in (1) above, in which the air mattress portion is folded inside the folded outer edge support member.
(3) A foldable air bed as described in (1) or (2) above, in which the air mattress portion comprises a breathable side material made of a breathable material and a cushion body enclosed in the breathable side material.
(4) The air mattress portion includes a non-breathable side material made of a non-breathable material and a cushion body enclosed in the non-breathable side material,
A foldable air bed according to (1) or (2) above, wherein the non-breathable side material has ventilation holes as the ventilation portion.
(5) The air mattress portion includes a non-breathable side material made of a non-breathable material,
A foldable air bed according to (1) or (2) above, wherein the non-breathable side material has a ventilation hole as the ventilation part and a sealing plug that can be repeatedly attached and detached to the ventilation part.

10...Air mattress portion 11...Side material 12...Upper surface 14...Lower surface 16...Ventilation portion 18...Ventilation hole 20...Air layer 30...Leg portion 32...Rib member 321...First rib member 322...Second rib member 323...Third rib member 34, 35, 36...Connecting member 40...Outer edge support member 50...Cushion body 52...Divided area 62...Loop portion 64...Attachment portion 66...Penetration portion 100...Foldable air bed

Claims (3)

an air mattress section having an upper surface, a lower surface, an air layer between the upper surface and the lower surface, and a ventilation section that allows ventilation between the air layer and the outside;
and legs for supporting the air mattress portion,
The air mattress portion includes a side material and a cushion body enclosed in the side material,
The cushion body is made of a foamed resin molded body having a thickness of 2 cm or more and 5 cm or less,
The leg portion is composed of a plurality of bone members and is foldable as a unit;
a closed state in which the leg portions are folded and the air mattress portion is disposed between the opposing rib members;
an open state in which the leg portions are spread and the air mattress portion is spread;
can be changed to
A foldable air bed, characterized in that the volume of the air mattress portion in the closed state is smaller than the volume of the air mattress portion in the open state. An outer edge support member is provided along the outer edge of the air mattress portion,
The outer edge support member is connected to the leg portion, and the outer edge support member is folded in conjunction with the leg portion being folded, and
2. The foldable air bed according to claim 1, wherein the air mattress portion is folded inside the folded outer edge support member. The air mattress portion includes a non-breathable side material made of a non-breathable material and a cushion body enclosed in the non-breathable side material,
3. A foldable air bed according to claim 1 or 2, wherein the non-breathable side material has ventilation holes as the ventilation portions.