Patent Application
20240099470
The present invention relates to an easy-assembly bed that is waterproof, lightweight, and can be easily assembled. The easy-assembly bed according to the present invention can also be used as a multipurpose table. Furthermore, the easy-assembly bed according to the present invention has a top plate that is usable as a lightweight board for transporting people and objects.
In recent years, there has been a series of disasters that have caused widespread damage. Often, temporary evacuation to safe places is conducted in disaster areas. However, if damages occur to houses or over a wide area, the evacuation may continue for a certain period. In such cases, it is necessary to secure privacy and safe beds as well as food and clothing.
Most shelters generally have wooden floors. Lying directly on the wooden floor takes away body temperature even with a mat laid on the floor. Energy is also necessary to get up from the floor when waking up.
The easy-assembly bed is effective in such situations. The bed has a use surface that is positioned at a certain height from the floor, and therefore both in the case of shifting from a standing posture to a lying posture and in the case of waking up and then standing up, it is easy to shift one's posture by temporarily sitting on the use surface.
On the other hand, the beds used in such cases are often stored in normal situations. In other words, it is necessary to transport the beds from a storage place to an evacuation place. Moreover, since the demand for beds is high in evacuation places, it is necessary to transport a large number of beds.
Beds made of corrugated cardboard are very advantageous in terms of transportation, since the corrugated cardboard is lightweight. Patent Literature 1 provides a corrugated cardboard bed that can be transported without a bulky volume. The beds made of corrugated cardboard in recent years take advantage of the lightweight of the material and make full use of structures such as U-shaped or B-shaped structures that exhibit increased compression strength even though the number of components increases slightly. As a result, a certain level of strength is ensured despite the beds being made of corrugated cardboard.
Patent Literature 2 discloses a bed using plastic cardboard to solve the problem in that the corrugated cardboard has low water resistance. The plastic corrugated cardboard is made of corrugated cardboard that is formed by using a resin such as a polypropylene, so as to have both strength and water resistance.
Patent Literature 3 discloses a bed made of wood, which allows easy assembly. While wooden beds were conventionally assembled by connecting each part with fastening tools such as bolts, use of notched joints allows the beds to be assembled simply by locking notches to each other.
As shown in Patent Literature 1, the number of components of the bed made of corrugated cardboard increases in order to ensure strength. As described above, the bed made of corrugated cardboard also has poor water resistance. Hence, in the event of disasters caused by a large amount of water, such as rain or flood, the strength of the bed is lost when the bed is exposed to water. In addition, when the bed made of corrugated cardboard is wet, a sanitary environment may be compromised due to reasons such as generation of insects such as psocoptera, posing a serious problem.
Meanwhile, the plastic corrugated cardboard as shown in Patent Literature 2 is made of plastic and therefore has high water resistance. However, the plastic corrugated cardboard has a corrugated cardboard structure in which a core with a waveform cross-section is interposed between upper and lower planar liners, which poses a problem in that water penetrates into the inside of the corrugated cardboard. In addition, it cannot be said that the plastic corrugated cardboard is structured to be resistant to forces applied in a direction perpendicular to the liners.
The wooden beds as shown in Patent Literature 3 are well-proven in terms of strength and water resistance. However, even though wood floats on water, the specific gravity is close to 1, and each member is heavy. Therefore, it cannot be said that the wooden beds are suitable for bulk transportation.
Moreover, the notched joints used in the wooden bed can provide a solid connection when respective locking grooves are formed with a negative tolerance and are hammered with a mallet or the like at the time of assembling a bed. However, a substantial amount of time and effort is required to disassemble the bed. On the other hand, when the locking grooves are formed with a positive tolerance, although assembling and disassembling the bed becomes easy, the bed experiences more rattling after assembly and there is a lack of connectivity between the members. As a result, when an attempt is made to lift the assembled bed, the components fall, and it is difficult to handle the assembled bed as an integrated article.
The present invention has been conceived in light of the above-mentioned problems, and provides an easy-assembly bed that is lightweight, highly water resistant, and can be easily assembled.
Specifically, an easy-assembly bed according to the present invention is an easy-assembly bed including: a top plate and a leg portion, the leg portion having a plurality of leg members that are linked using notched joints, wherein:
In the easy-assembly bed according to the present invention, since the front and rear board members are respectively placed on the front and rear surfaces of the foam plate, and the cut ends that are side surfaces, the foam plate, and the front and rear board members are molded with a molded resin, the foam plate is sealed with the resin and the front and rear board members. Therefore, since the foam body is completely protected from penetration of water, it has excellent water resistance.
In addition, since the center part is formed with a foam body, the specific gravity is low, and the specific gravity of the top plate and the leg portion is lower than that of wood. Naturally, both the top plate and the leg portion float on water. Furthermore, since the top plate is mostly made of a foam body, it has high heat retaining properties. This makes it possible to suppress a decrease in the body temperature of a person who sleeps on the top plate.
Moreover, as the structure of the foam body sandwiched between the board members made of plastic is strong, a bed with sufficient strength can be obtained even with a small number of components (a top plate and several leg members). Furthermore, since the number of components is small, it is extremely easy to assemble the assembly bed, and even those who have never seen the assembly bed can assemble the bed in a few minutes without instructions. Since the number of components is small and all the components are planar, the bed does not become bulky when the components are stored.
In addition, not only does the molded resin portion that is molded with a molded resin seal the foam body and the upper and lower top plates, but the molded resin portion can also be formed continuously with an additional shape portion, which exhibits other functions. Specifically, the additional shape portion is an L-form shape or the like provided on the rear surface of the top plate so as to lock the leg portion and the top plate. Therefore, it is not necessary to separately prepare components that exhibit such functions.
Since the resin molding is also applied to the parts of the locking grooves, the molded resin absorbs the tolerance between the components when the leg members are joined together by notched joints. This makes it easy to assemble and disassemble the bed, and the leg portion is not wobbly when the bed is assembled. As a result, when the leg members are connected to one another, they can be carried as a leg portion.
In addition, since the assembly bed according to the present invention has no metal part, there is no interaction with magnetism or radiation. Therefore, it is possible to directly examine a living body laid on the top plate by CT or MRI. It is also possible to place the bed itself in an MRI chamber. More specific examples of use include use as a top plate of an ambulance stretcher or use as a stretcher at a security inspection place in an airport.
Hereinafter, an easy-assembly bed according to the present invention will be described with reference to the drawings. The following description illustrates an embodiment of the present invention and is not intended to limit the present invention to the following description. The following description may be modified to the extent that it does not depart from the spirit of the present invention.
The easy-assembly bed according to the present invention can also be used as a multipurpose table as is. Furthermore, a top plate of the easy-assembly bed according to the present invention can be used as a transportation lightweight board, when the top plate is used as a single unit.
The top plate 10 is formed into a size and a shape that allows a person to lie on the plate. Although the top plate 10 is typically fabricated into a rectangle shape in plan view, the shape is not limited thereto. For convenience in transportation, the top plate 10 may be constituted of two or more top plates 10.
A height of about 30 cm is preferably adopted for the leg members 20 in order to avoid bacteria (viruses) and dust that move from the floor to the top plate 10. The leg members 20 may also have an arch shape as a reinforcing structure. The leg members 20 include locking grooves 22 (denoted by 22u or 22d in
The short leg members 20c, 20d and 20e each have two locking grooves 22, and the long leg members 20a and 20b each have three locking grooves 22, one each at both ends and in the center. The long leg members 20a and 20b each include upward locking grooves 22u. The short leg members 20c, 20d and 20e each include two downward locking grooves 22d, one each at both ends.
By engaging the locking grooves 22d of the short leg members 20c, 20d and 20e with the locking grooves 22u of the long leg members 20a and 20b, the long leg members 20a and 20b are connected to the short leg members 20c, 20d and 20e by notched joints. The leg portion 30 is completed by locking the three short leg members 20c, 20d and 20e to the two long leg members 20a and 20b (see
The bed members 40 each have a plate-shaped foam plate 42 arranged in a center layer in the thickness direction, with a front board member 44 and a rear board member 46 being bonded to the front surface and the rear surface of the foam plate 42. The foam plate 42 with the front board member 44 and the rear board member 46 bonded thereto is referred to as a bonded material 48. The parts corresponding to the side surfaces of the bonded material 48 are referred to as cut ends 48a. The bonded material 48 of the top plate 10 may be referred to as a “top plate bonded material” and the bonded material 48 of each of the leg members 20 may be referred to as a “grooved bonded material”.
In the bed members 40, parts of the cut ends 48a are covered with a molded resin. The molded resin parts are each referred to as a molded resin portion 50. It can be said that in the molded resin portion 50, the front board member 44, the rear board member 46, and the foam plate 42 are molded at the cut ends 48a. The molded resin portion 50 of the top plate 10 may be referred to as a “top plate molded resin portion”, and the molded resin portion 50 of each of the leg members 20 may be referred to as a “leg member molded resin portion.”
The foam plate 42 is formed in the shape of a plate. Although the shape in plan view is not particularly limited, the thickness is small in comparison with the length and width. For the foam plate 42, materials that can typically be used as a foam body can be used. Examples of the materials include a polyurethane-based resin, a polystyrene-based resin, and a polyolefin-based resin. Here, a polyolefin includes a polyethylene and a polypropylene. Materials such as a phenol resin, a polyvinyl chloride, a urea resin, silicone, a polyimide, and a melamine resin can also be used. Note that the foam plate 42 of the top plate 10 may be referred to as a “top plate foam plate” and the foam plate 42 of each of the leg members 20 may be referred to as a “grooved foam plate”.
For the front board member 44 and the rear board member 46, plate-shaped resin or plate-shaped FRP can be suitable for use because the material itself is lightweight, strong, and water resistant. Here, the front board member 44 and the rear board member 46 may be made of different materials. The front board member 44 and the rear board member 46 may also be different in thickness. The front board member 44 and the rear board member 46 are bonded to the foam plate 42 with an adhesive. As a suitable adhesive to be used, a two-component epoxy-based adhesive or a two-component urethane-based adhesive can be used because no oxygen is present in the vicinity of the center of the foam plate 42, and therefore the adhesive needs to have a property of being curable even without air during curing. The front board member 44 and the rear board member 46 of the top plate 10 may be referred to as a “top plate front board member” and a “top plate rear board member”, respectively, and the front board member 44 and the rear board member 46 of each of the leg members 20 may be referred to as a “grooved front board member” and a “grooved rear board member,” respectively.
While the molded resin portion 50 covers all the cut ends 48a of the bonded material 48 with a molded resin, an additional shape portion 52 that is formed with a molded resin may further be provided. With reference to
The regulation shapes 12a are locked to the corner parts of the leg portion 30 when the top plate 10 is locked to the leg portion 30. Further, the regulation shapes 12a regulate the top plate 10 to prevent the top plate 10 from shifting over the leg portion 30.
The molded resin portion 50 is formed by attaching a mold corresponding to the molded resin portion 50 to the part of the cut ends 48a after the bonded material 48 is formed, and injecting a molded resin into the mold. In this case, when the shape corresponding to the additional shape portion 52 is also formed, the additional shape portion 52 can also be formed concurrently with the formation of the molded resin portion 50.
As the molded resin usable for the molded resin portion 50, the resin usable for the foam plate 42 can be used. However, the cut ends 48a of the bed members 40 may be subjected to accidental external force that is generated when the cut ends 48a are hit or rubbed. At the locking grooves 22 of the leg members 20, the molded resin portions 50 slide in contact with each other when the leg members 20 are locked to each other. Therefore, a highly durable urethane resin is a suitable material to be used for the molded resin portions 50.
There is no upper limit to a thickness 50t of the molded resin portion 50 as long as water cannot penetrate through the cut ends 48a of the bonded material 48. However, in many cases, the specific gravity of the molded resin is 1 g/cm3 or more. Thus, as the thickness 50t of the molded resin portion 50 becomes greater, the specific gravity of the easy-assembly bed 1 becomes higher. For the molded resin portion 50, a thickness 50t of about 2 to 10 mm is suitable.
On the other hand, a formation length 50L of the molded resin portion 50 may be formed greater than a thickness 48t of the bonded material 48. Here, the formation length 50L is the length of the molded resin covering the cut ends 48a of the bonded material 48 in the thickness direction of the bed members 40, and specifically, the length is the thickness of the bed members 40 as viewed from the side of the cut ends 48a (see
For example, to link the leg members 20 with notched joints without wobbling, the locking grooves 22 require high precision machining. However, the greater the formation length 50L of the molded resin portion 50 is formed than the thickness 48t of the bonded material 48, the more dimensional error can be absorbed. Of course, the formation length 50L of the molded resin portion 50 may be equal to the thickness 48t of the bonded material 48.
Again as can be seen in
When the center layer is made of wood, a tape-shaped or flat plate-shaped material referred to as a cut end decorative material is bonded for reinforcement of the side surfaces. However, in each of the bed members 40 constituting the top plate 10 and the leg members 20, since the center layer is the foam plate 42, sufficient bonding strength cannot be obtained by bonding the cut end decorative materials to the foam plate 42 with an adhesive.
However, as in the present invention, when the penetrated regions 48f are formed in the foam plate 42 by molding the cut ends 48a of the bonded material 48, the molded resin portion 50 and the foam plate 42 can be bonded with a sufficiently strong bonding strength.
In the easy-assembly bed 1 according to the present invention, it is desirable that a total specific gravity of the top plate 10 and five leg members 20 is 0.6 g/cm3 or less. This is because the total weight can be reduced, and a large force is not required at the time of assembling and disassembling. In addition, when the specific gravity is 0.6 g/cm3 or less, the bed sufficiently floats on water. The specific gravity of the bed members 40 is determined by the size of each portion which is determined by the strength required for the bed. While the lower the specific gravity the better, there is no point in specifying a lower limit since there is no possibility of the specific gravity becoming zero or negative. In reality, 0.1 g/cm3 or more or 0.3 g/cm3 or more may be a realistic lower limit.
A method of assembling the easy-assembly bed 1 according to the present invention is as shown in
As shown in
One top plate 14 and the four leg members 20 are combined into a shape like that of a low dining table. This is referred to as a “half table 3.” Now, for the sake of convenience, two half tables 3 in
At the end sides opposite to the end sides where the link shapes 12b are formed, the L-shaped regulation shapes 12a shown in
The easy-assembly bed according to the present invention can be used as a bed and also as a multipurpose table. For example, the easy-assembly bed 1 shown in
By forming the legs 12c with such additional shape portions 52, it is possible to create spaces for hands to be inserted into when, for example, lifting the top plate 16 with an injured person being laid on, wherein the top plate 16 placed directly on the ground. In other words, the top plate 16 itself, with the additional shape portions 52 (legs 12c) added to the molded resin portion 50, can be used in the field of medical treatment. Such a top plate 16 can be referred to as a medical transportation lightweight board. The medical transportation lightweight board may also be made splittable as shown in
The medical transportation lightweight board using the top plate 16 does not use any metal at all and thus can be used for CT and MRI as it is. In other words, in an emergency, it is possible to perform a detailed examination of an injured person laying on the medical transportation lightweight board by CT or MRI without transferring the injured person to another stretcher or the like.
An easy-assembly bed of a type shown in
Load heads 60 were adjusted to apply ½ of load PF (kN) to a portion between the short leg members 20c and 20d and to a portion between the short leg members 20d and 20e. A sinking volume in the middle of the top plate 10 was defined as a displacement δ (mm) due to the load PF. The result of the load test is shown in
In
The easy-assembly bed according to the present invention can be suitably used as an emergency bed, and is also usable as a regular bed since it is lightweight and excellent in portability. The easy-assembly bed according to the present invention can also be used as a multipurpose table. Furthermore, the easy-assembly bed according to the present invention has a top plate that is usable as a medical lightweight board.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2020-211252 | Dec 2020 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2021/046966 | 12/20/2021 | WO |
