Cover for bed mattress and method for manufacturing same

Abstract

When an inner material of a bed mattress is soft, the inner material is compressed by a cover body and the flatness of the inner material is inhibited. As a result, at a corner portion, the linearity of an edge portion on a boundary between flat surfaces may be impaired, and the design may not be exhibited as intended. In a cover body of the present invention for covering an inner material of a bed mattress, a corner portion of the inner material includes a pair of flat portions arranged vertically and an edge portion between the pair of flat portions, the cover body includes a corner covering portion covering the corner portion of the inner material, the corner covering portion is formed of a continuous fabric, and the corner covering portion includes a variable portion facing the edge portion of the inner material and a sheet portion facing each of the flat portions, and the variable portion has a shape-retaining property lower than that of the sheet portion.

Description

TECHNICAL FIELD

[0001] The present invention relates to an improvement of a cover body for a bed mattress and a method for sewing the same.BACKGROUND ART

[0002] A bed mattress includes an inner material having cushioning properties, and a cover body covering the inner material.

[0003] It is preferable to make the cover body removable from the inner material for ease of washing and the like, and for ease of changing the design.

[0004] Patent Literature 1 is referred to as literature disclosing a technique related to the present invention.CITATIONS LISTPATENT LITERATURE

[0005] Patent Literature 1: JP 2020-81382 ASUMMARY OF INVENTIONTECHNICAL PROBLEMS

[0006] The cushioning properties of the inner material of the bed mattress are adjusted in various ways depending on the aspects of usage required for the bed mattress.

[0007] Here, the following problems have been observed when softness is required for the inner material of the bed mattress.

[0008] In general, to avoid occurrence of wrinkles on the front surface of the cover body, the inner material is tightly and entirely covered with the cover body. At this time, when the inner material of the bed mattress is soft, the inner material is compressed in the thickness direction by the cover body, causing the side surface of the bed mattress to deform. A bed mattress including a plate-shaped inner material is to have flat upper and side surfaces. However, when the inner material is soft, the inner material is compressed by the cover body, and the side surface of the inner material bulges outward or becomes wrinkled, so that the flatness is hindered. As a result, the linearity of an edge portion on the boundary between the upper surface (or the lower surface) and the side surface, or the boundary between the side surfaces, may be impaired at a corner portion of the bed mattress, and the design may not be exhibited as intended.

[0009] By preparing a plurality of pieces of fabric, sewing the edge portions thereof together to form a cover body, and positioning the sewn edge portions to face the edge portion of the inner material, the linearity of the portion of the cover body facing the edge portion can be ensured. However, it takes time and effort to sew the plurality of pieces of fabric together, and when a sewn portion is present at the corner covering portion of the cover body, and the sewn portion faces the corner portion of the inner material, the corner covering portion cannot completely follow the corner portion of the inner material, thereby creating a space therebetween, even if only slightly. This space may impair the design of the corner portion of the bed mattress.

[0010] Ensuring the linearity of a section facing an edge portion of an inner material in a cover body that entirely covers the inner material is also required for a type of cover body that covers the upper surface and the side surfaces of an inner material and leaves the bottom surface open (cf. FIG. 5). This is because, in such a type of cover body main portion 30, a linear elastic body such as rubber is sewn into end edges 34 of side fabric portions 32L, 32S facing the side surfaces of an inner material 10 (edge portions facing the bottom edge of the inner material 10), so that the inner material 10 may be compressed in the thickness direction.

[0011] Such a type of cover body main portion 30 further has a problem of displacement relative to the inner material 10. That is, when a user rolls over in bed, as illustrated in FIG. 5(B), the cover body main portion 30 may be displaced as the user moves. If the elastic force of the linear elastic body at the end edge 34 is increased to prevent displacement, the compressive force in the thickness direction of the inner material 10 increases and the deformation of the inner material 10 is promoted, so that a certain limitation is imposed on the elastic force of the linear elastic body.SOLUTIONS TO PROBLEMS

[0012] The present invention has been made to solve the above problems, and a first aspect thereof is defined as follows. That is, a cover body that entirely covers an inner material of a bed mattress, in which a corner portion of the inner material includes a pair of flat portions arranged vertically and an edge portion between the pair of flat portions, the cover body includes a corner covering portion covering the corner portion of the inner material, the corner covering portion includes a continuous fabric, and the corner covering portion includes a variable portion facing the edge portion of the inner material and a sheet portion facing each of the flat portions, and the variable portion has a shape-retaining property lower than that of the sheet portion.

[0013] According to the cover body defined as above, by positioning the variable portion of the corner covering portion to face the edge portion of the corner portion of the inner material and positioning the sheet portion of the corner covering portion to face the flat portion of the inner material, the corner covering portion can face the inner material along the corner portion of the inner material without a gap. This is caused by the following: a space is unlikely to be formed between the cover body and the inner material because the corner covering portion is formed of a continuous fabric; and / or the variable portion facing the edge portion of the inner material deforms preferentially due to having a small shape-retaining property. In other words, the stress of the cover body concentrates on the variable portion, thereby suppressing the deformation of the sheet portion.

[0014] Since the deformation of the sheet portion is suppressed in the corner covering portion of the cover body, the deformation of the side surfaces, the upper surface, and the lower surface of the bed mattress is suppressed, and the flatness thereof is maintained. Since the deformation of the side surfaces, the upper surface, and the lower surface of the mattress is suppressed, the linearity of the edge portion connecting the respective flat surfaces is also maintained.

[0015] The deformation of the corner covering portion concentrates on the variable portion having a small shape-retaining property. In other words, even if the variable portion having a small shape-retaining property deforms, this does not cause deformation of the edge portion of the inner material, and the variable portion rather deforms along the edge portion. Thus, the linearity of the edge portion of the inner material is maintained.

[0016] A cover body defined in a second aspect of the present invention is defined as follows.

[0017] In the cover body defined in the first aspect, a part of the continuous fabric is folded and sewn in the sheet portion of the corner covering portion.

[0018] According to the cover body of the second aspect defined as above, the fabric is folded and sewn, thereby increasing the shape-retaining property of the sheet portion. Since the fabric constitutes the corner covering portion including the deformation portion, the number of components of the cover body can be minimized. This enables a reduction in the manufacturing cost of the cover body.

[0019] A cover body defined in a third aspect of the present invention is defined as follows.

[0020] In the cover body defined in the first aspect, the sheet portion of the corner portion is reinforced by another member.

[0021] According to the cover body of the third aspect defined as above, the shape-retaining property can be increased by reinforcing the sheet portion with another member. The degree of reinforcement of the sheet portion can be arbitrarily adjusted by selecting material characteristics or the like of another member.

[0022] When the cover body is of a type that covers the upper surface and the side surfaces of the inner material and leaves the bottom surface open, another aspect (sixth aspect) of the present invention is defined as follows. That is, a cover body covering an upper surface and side surfaces of an inner material of a bed mattress, and leaving a bottom surface of the inner material open, in which a corner portion of the inner material includes a pair of the side surfaces arranged vertically and an edge portion between the pair of side surfaces, the cover body includes a corner covering portion covering the corner portion of the inner material, and the corner covering portion includes a variable portion facing the edge portion of the inner material, a first side contact portion and a second side contact portion facing the respective side surfaces of the pair of side surfaces, and a bottom contact portion facing the bottom surface of the inner material, and the variable portion has a shape-retaining property lower than those of the first side contact portion and the second side contact portion.

[0023] According to the cover body of the sixth aspect defined as above, the linearity of the section facing the edge portion is ensured by the presence of the variable portion. Furthermore, even if a force is applied to the upper surface of the cover body with movement of a user, the bottom contact portion provided in the corner covering portion contacts the bottom surface of the inner material, and the movement is suppressed. Accordingly, displacement of the cover body relative to the inner material does not occur.

[0024] The variable portion of the cover body as described above can be configured as follows (seventh aspect).

[0025] That is, the first side contact portion and the second side contact portion are connected by the bottom contact portion, and the variable portion is formed by opening a portion facing the edge portion or by bringing edges into an unconnected state, the edges facing each other in the first side contact portion and the second side contact portion.

[0026] An eighth aspect of the present invention is defined as follows. That is, the cover body defined in the sixth aspect further includes: an upper fabric portion facing the upper surface of the inner material; a side fabric portion facing each of the side surfaces of the inner material; and a corner fabric portion constituting the corner covering portion.

[0027] In the cover body of the eighth aspect defined as above, since the three fabric portions, which are the upper fabric portion, the side fabric portion, and the corner fabric portion, are independent, the degree of freedom in designing each fabric portion is improved.

[0028] Note that a part of the upper fabric portion and a part of the side fabric portion can be made of the same continuous fabric.

[0029] A ninth aspect of the present invention is defined as follows. That is, in the cover body defined in the eighth aspect, in the corner fabric portion, fabric of each of the first side contact portion and the second side contact portion has a shape-retaining property higher than that of fabric of the side fabric portion.

[0030] According to the cover body of the eighth aspect defined as above, in the fabric facing the side surface of the inner material, the shape-retaining properties of the first and second side contact portions of the corner fabric portion are enhanced. This makes it possible to suppress deformation of the inner material due to compression.

[0031] A measure for enhancing the shape-retaining properties of the first and second side contact portions of the corner fabric portion is arbitrary, but for example, as defined in a tenth aspect, superimposing the corner fabric portion on the side fabric portion can be employed. When such a measure is employed, the rigidity of the superimposed portion formed by the side fabric portion and each of the first and second side contact portions increases, thereby enhancing the shape-retaining property thereof. The superimposed portion is sewn by stitching, thereby enabling further improvement in the shape-retaining property. A reinforcing sheet can also be applied to the superimposed portion.

[0032] Each of the first and second side contact portions of the corner fabric portion may be continuously coupled to the side fabric portions. In this case, the shape-retaining property can be improved by applying the reinforcing sheet to each of the first and second side contact portions.

[0033] As long as the reinforcing sheet is made of a material having rigidity higher than that of the side fabric portion, the material characteristics of the reinforcing sheet are not particularly limited. A thin plate of a flexible polymeric material such as a foam material can be employed.

[0034] Another aspect (thirteenth aspect) of the present invention is defined as follows. That is, a cover body covering an upper surface and side surfaces of an inner material of a bed mattress, and leaving a bottom surface of the inner material open, in which a corner portion of the inner material includes a pair of the side surfaces arranged vertically and an edge portion between the pair of side surfaces, the cover body includes a single piece of original fabric including an upper fabric portion facing the upper surface of the inner material, side fabric portions facing the side surfaces, and a corner fabric portion facing the corner portion, the side fabric portions, continuous with respective sides of the upper fabric portion formed in a rectangular shape in the original fabric, are arranged such that adjacent ones of the side fabric portions are orthogonal to each other, and in the corner fabric portion, a ridge line disposed between the adjacent side fabric portions and directed outward from a corner part of the upper fabric portion is folded in a mountain fold along an edge portion of the corner portion, and the ridge line folded in the mountain fold serves as a variable portion, and in the corner fabric portion, a folded portion excluding the ridge line is sewn to have a shape-retaining property higher than that of the variable portion.

[0035] According to the cover body of the thirteenth aspect defined as above, an action similar to that of the cover body defined in the first aspect is exerted. Furthermore, since the cover body is formed from a single piece of original fabric, effective use of fabric is promoted, and cost reduction can be achieved.BRIEF DESCRIPTION OF DRAWINGS

[0036] FIG. 1 is a schematic view illustrating a relationship between an inner material and a cover body. FIG. 2 is a schematic view illustrating a state in which the inner material is covered with the cover body according to an embodiment of the present invention. FIG. 3 is a schematic view illustrating a state in which the inner material is covered with a cover body according to another embodiment of the present invention. FIG. 4 is a schematic view illustrating a cover body according to another embodiment of the present invention and a state in which the inner material is covered with the cover body. FIG. 5(A) illustrates an exploded perspective view of a conventional inner material and a cover body covering the upper surface and the side surfaces of the inner material and leaving the bottom surface open, and FIG. 5(B) illustrates a schematic view illustrating displacement of the cover body relative to the inner material. FIG. 6 illustrates a cover body of another embodiment that covers the inner material, FIG. 6(A) illustrates a top-side perspective view, and FIG. 6(B) illustrates a bottom-side perspective view. FIG. 7 illustrates a corner covering portion that is applied to the cover body of FIG. 6, FIG. 7(A) illustrates a back-side perspective view, and FIG. 7(B) illustrates a developed view. FIG. 8 illustrates a cover body according to another embodiment of the present invention, FIG. 8(A) illustrates a top-side perspective view, and FIG. 8(B) illustrates a developed view. FIG. 9 is a bottom-side perspective view of a state in which the inner material is covered with the cover body of FIG. 8, and a corner covering portion of another embodiment is applied. FIG. 10 illustrates a corner covering portion of another embodiment, FIG. 10(A) illustrates a back-side perspective view, and FIG. 10(B) illustrates a developed view. FIG. 11 is a bottom-side perspective view illustrating an example of a cover body including a bottom fabric portion. DESCRIPTION OF EMBODIMENTS

[0037] Hereinafter, embodiments of the present invention will be described.

[0038] FIG. 1 illustrates an inner material 10 and a cover body 20, FIG. 1A illustrates the inner material 10, FIG. 1B illustrates the cover body 20, and FIG. 1C illustrates a bed mattress 1 in which the inner material 10 is covered with the cover body 20.

[0039] The inner material 10 is a plate-shaped cushion member.

[0040] The cushion member can be arbitrarily selected according to the application and use situation of the bed mattress. For example, a filament three-dimensional conjugate fiber (trade name: Airfiber, manufactured by Airweave Inc.), a polyurethane foam, and the like can be selected. The inner material 10 may be formed of the same material as a whole, or may be formed of different materials (material characteristics, degrees of foaming) in the thickness direction and / or the width direction to adjust hardness and repulsive force.

[0041] The shape of the inner material 10 can be arbitrarily designed according to the bed serving as a base, but is generally a rectangular thin plate shape.

[0042] Therefore, the inner material 10 includes an upper surface (flat surface 11) and side surfaces (flat portions 12, 13) orthogonal to each other, the adjacent flat portions include an edge portion 15 linear in the vertical direction, and the flat portions 12, 13 adjacent to the flat surface 11 include edge portions 16, 17 linear in the horizontal direction. At least a pair of flat portions and the edge portion form a corner portion. For example, the flat portion 12, the flat portion 13, and the edge portion 15 form a corner portion 19.

[0043] In this example, as the inner material 10, a filament three-dimensional conjugate fiber having a height of 10 to 600 mm, a width of 300 to 2500 mm, and a length of 1000 to 2500 mm is employed.

[0044] The cover body 20 is made of fabric and is a bag body having the same outer diameter dimension as the outer dimension of the inner material 10. One side can be opened and closed by a linear fastener to accommodate the inner material 10.

[0045] Reference numeral 21 in the figure denotes a corner covering portion, which faces the corner portion of the inner material 10.

[0046] In the following description, attention will be paid to the corner covering portion 21 and the corner portion 19, where the side surface (flat portion 12) and the side surface (flat portion 13) are connected by the edge portion 15 in the inner material 10.

[0047] FIG. 2A illustrates a detailed configuration of the corner covering portion 21 of the cover body 20.

[0048] The corner covering portion 21 is made of a single piece of fabric 25 and includes a variable portion 22 and sheet portions 23.

[0049] The variable portion 22 is sandwiched by the sheet portions 23, and the fabric 25 is not folded in any way in the variable portion 22 and is formed as a single piece. In the sheet portion 23, the fabric 25 is folded downward from the variable portion 22, and the folding is triple and sewn with reinforcing thread 27.

[0050] According to the corner covering portion 21 configured as described above, the fabric 25 is continuous on the design surface (uppermost surface). Therefore, the corner covering portion 21 can be provided with a unique design. For example, it is easy to form a pattern on the corner covering portion 21.

[0051] In the example of FIG. 2(B), the end edge of the sheet portion 23 (the edge opposite to the variable portion 22) extends to the middle of each of the flat portion 12 and the flat portion 13. If the corner covering portion 21 of the cover body 20 exhibits its function and does not cause any deformation of the corner portion 19 of the inner material 10 to follow its original shape, the design as a bed mattress is not impaired.

[0052] Naturally, the sheet portion of the cover body 20 may be provided to face the entire surface of the flat portion 12 and the entire surface of the flat portion 13 of the inner material 10, or the relatively short sheet portion 23 illustrated in FIG. 2(A) may be repeatedly arranged.

[0053] The degree of folding (superimposition) of the fabric 25 in the sheet portion 23 is arbitrarily selected according to the shape-retaining property required for the sheet portion 23 in consideration of the bending property of the fabric 25 itself, the density of sewing, and the like. To pull out the end edge of the fabric 25 from the sheet portion 23, folding is performed an odd number of times of 3 or more.

[0054] As long as a sufficient shape-retaining property can be ensured for the sheet portion 23, the density of sewing can also be arbitrarily selected.

[0055] The sewing pattern is arbitrary, and a general-purpose stitch pattern can be employed to provide any design to the sheet portion 23.

[0056] The color and thickness of the reinforcing thread 27 are also arbitrarily selected. Sewing the sheet portion 23 with one reinforcing thread 27 is preferable from the viewpoint of ease of sewing, but the fabric of one sheet portion 23 may also be sewn using a plurality of reinforcing threads 27, each having a different color or stitch pattern.

[0057] The cover body 20 illustrated in FIG. 2 can be formed as follows.

[0058] A continuous fabric 25 is prepared. The width of the fabric 25 is three times or more the total width of the flat portions 12, 13 of the inner material 10.

[0059] Next, a portion facing the edge portion of the inner material 10, that is, the variable portion 22, is defined. At this time, the fabric is provided on both sides of the variable portion 22, with widths equal to or greater than three times the widths of the flat portion 12 and the flat portion 13, respectively.

[0060] Next, the portion of the fabric 25 on each side of the variable portion 22 is folded in a triple manner and temporarily secured with a needle, a tape, or the like.

[0061] The folded portion is sewn by stitching.

[0062] In the cover body 20 formed in this manner, the shape-retaining property of the variable portion 22, in which the fabric 25 is a single piece, is lower than the shape-retaining property of the sheet portion 23, in which the fabric 25 is folded in a triple manner and reinforced by stitching.

[0063] As a result, when the inner material 10 is tightly covered with the cover body 20, the variable portion of the corner covering portion of the cover body deforms along the edge portion of the inner material 10 to maintain the linearity, and the sheet portion having the high shape-retaining property faces the flat portion of the inner material to maintain the flatness.

[0064] FIG. 3 illustrates a corner covering portion 121 of a cover body according to another embodiment. Note that the same elements as those in FIG. 2 are denoted by the same reference numerals, and the description thereof will be omitted.

[0065] The corner covering portion 121 has a structure in which a variable portion 122 is sandwiched between sheet portions 123, 123, and the sheet portions 123, 123 and the variable portion 122 are connected by a continuous fabric 25. A reinforcing sheet 130 is attached to the back surface (the surface facing the inner material 10) of the sheet portion 123 to make the shape-retaining property of the sheet portion 123 higher than that of the variable portion 122.

[0066] By attaching the reinforcing sheet 130 to the back surface of the sheet portion 123, the continuous fabric 25 is exposed in a plain state on the front surface of the corner covering portion 121. This provides simple design to the corner covering portion 121.

[0067] In the above example, the reinforcing sheet 130 is attached to the back surface of the sheet portion 123, but a bag can be provided in the sheet portion 123, and the reinforcing sheet can be inserted into the bag. It is not avoided to sew the reinforcing sheet 130 to the fabric of the sheet portion 123.

[0068] As long as the material of the reinforcing sheet 130 has higher rigidity than that of the fabric 25, the material characteristics of the reinforcing sheet 130 are not particularly limited. A thin plate of a flexible polymeric material such as a foam material can be employed.

[0069] FIG. 4 illustrates a corner covering portion 221 of a cover body of another embodiment. Note that the same elements as those in FIG. 2 are denoted by the same reference numerals, and the description thereof will be omitted.

[0070] The corner covering portion 221 has a structure in which a variable portion 222 is sandwiched between sheet portions 223, 223, and the sheet portions 223, 223 and the variable portion 222 are connected by a continuous fabric 25.

[0071] In this example, a short second folded portion 2231 is provided at a portion connected to the variable portion 222 in the sheet portion 223. Although the fabric 25 is also folded in the second folded portion 2231, the density of sewing with the reinforcing thread 27 is smaller than that of a main body portion 2233 of the variable portion 222, and the shape-retaining property is between those of the main body portion 2233 and the variable portion 222.

[0072] This enables smooth deformation between the variable portion 222 and the sheet portion 223.

[0073] By providing the second folded portion 2231, the width of the variable portion 222 can be further narrowed.

[0074] The width of the second folded portion 2231 is not particularly limited, but can be the same as or twice the width of the variable portion 222.

[0075] FIG. 6 illustrates a cover body 30A of another example.

[0076] The cover body 30A has a configuration in which a corner covering portion 40 is superimposed on the conventional cover body main portion 30. Note that the same elements as those in FIGS. 1 and 5 are denoted by the same reference numerals, and the description thereof will be omitted.

[0077] The cover body main portion 30 includes an upper fabric portion 31 and side fabric portions 32L, 32S. In this example, the long belt-shaped side fabric portion 32L and the short belt-shaped side fabric portion 32S are prepared, and one edge of each of those portions is sewn to the peripheral edge of the rectangular upper fabric portion 31 to form the bottomless box type cover body main portion 30. At this time, the facing edges of the side fabric portion 32L and the side fabric portion 32S may or may not be sewn together.

[0078] A corner fabric portion cut out in the developed view illustrated in FIG. 7(B) is bent along dotted lines to form the three-dimensional corner covering portion 40 illustrated in FIG. 7(A). A first side contact portion 41 and a second side contact portion 42 are superimposed on the side fabric portion 32L and the side fabric portion 32S, respectively, and are sewn at a fine pitch by stitching. In this example, an inner edge 411 of the first side contact portion 41 and an inner edge 412 of the second side contact portion 42 are sewn together.

[0079] In such a state, the shape-retaining properties of the first side contact portion 41 and the second side contact portion 42, which are superimposed on and sewn to the side fabric portion 32S and the side fabric portion 32L, respectively, are higher than the shape-retaining property of the connection portion between the inner edge 411 of the first side contact portion 41 and the inner edge 412 of the second side contact portion 42. A linear section obtained by sewing the inner edge 411 of the first side contact portion 41 and the inner edge 412 of the second side contact portion 42 is a variable portion facing the edge portion 15 of the inner material 10.

[0080] When the facing end edges of the side fabric portion 32L and the side fabric portion 32S are connected, the sewing of the inner edge 411 of the first side contact portion 41 and the inner edge 412 of the second side contact portion 42 can be omitted.

[0081] A material for forming the corner covering portion 40 is not particularly limited, but is preferably the same as, or the same type of fabric material as, that for the cover body main portion 30.

[0082] The widths of the first side contact portion 41 and the second side contact portion 42 are preferably equal to each other, but the widths may be different from each other. The widths can be 1 / 4 to 1 / 1 of the thickness of the inner material 10.

[0083] According to the cover body 30A configured as described above, bottom contact portions 43 of the corner covering portion 40 arranged at the respective corner portions of the inner material 10 contact the bottom surface of the inner material 10. Therefore, even when a force parallel to the upper surface of the inner material 10 is applied, the cover body 30A is not displaced relative to the inner material 10.

[0084] Furthermore, the shape-retaining properties of the first side contact portion 41 and the second side contact portion 42 are higher than the shape-retaining property of the linear section (variable portion) in which the inner edge 411 of the first side contact portion 41 and the inner edge 422 of the second side contact portion 42 contact each other. Therefore, the variable portion easily follows the edge portion 15 of the inner material 10 and its linearity can be ensured, and even if the cover body 30A compresses the inner material 10, the shape of the side surface can be prevented from collapsing.

[0085] FIG. 8 illustrates a cover body 30B of another embodiment. In FIG. 8, the same elements as those in FIG. 6 are denoted by the same reference numerals, and the description thereof will be omitted.

[0086] The cover body 30B is formed from a single piece of fabric (original fabric) illustrated in FIG. 8(B). The original fabric includes a rectangular upper fabric portion 31, side fabric portions 32L, 32S, and a corner fabric portion 50.

[0087] The long band-shaped side fabric portions 32L, 32L are continuous with a pair of long edges of the upper fabric portion 31, and the short band-shaped side fabric portions 32S, 32S are continuous with a pair of short edges of the upper fabric portion 31.

[0088] The corner fabric portion 50 has a fan shape and is continuously formed between the side fabric portion 32L and the side fabric portion 32S. The corner fabric portion 50 is also continuous with a corner part of the upper fabric portion 31.

[0089] The corner fabric portion 50 is folded as follows. A ridge line 51, which extends outward from the corner part of the upper fabric portion 31 and divides the corner fabric portion 50 into two parts, is folded into a mountain fold. A ridge line 53, which divides a portion between the ridge line 51 and each of the ridge lines 55, 55 defining the end edges of the side fabric portion 32L and the side fabric portion 32S into two parts, is folded into a valley fold. The ridge lines 51, 55 are then brought into alignment. By sewing the superimposed fabric portions in this state, a bottomless box-shaped cover body 30B is formed as illustrated in FIG. 8(A).

[0090] FIG. 9 illustrates a state in which the inner material 10 is covered with the cover body 30B of FIG. 8. In this example, a corner covering portion 140 is attached to each corner part of the cover body 30B (cf. FIG. 10). The attachment is performed by sewing a first side contact portion 141 and a second side contact portion 142 to the side fabric portion 32L and the side fabric portion 32S, respectively.

[0091] In the corner covering portion 140, the first side contact portion 141 and the second side contact portion 142 are connected by a bottom contact portion 143. An inner edge 1411 of the first side contact portion 141 and an inner edge 1421 of the second side contact portion 142 are separated from each other.

[0092] According to the corner covering portion 140 configured in this manner, compared to the corner covering portion 40 in FIG. 7, the bottom contact portion 143 is shifted to the center side as viewed from the corner part of the inner material 10 and has a larger area, so that the cover body 30B is less likely to be displaced relative to the inner material 10.

[0093] In the corner covering portion 140, a space portion between the first side contact portion 141 and the second side contact portion 142 constitutes a variable portion.

[0094] FIG. 11 illustrates a cover body 30C of another embodiment. In FIG. 11, the same elements as those in FIG. 6 are denoted by the same reference numerals, and the description thereof will be omitted.

[0095] The cover body 30C includes a bottom fabric portion 35. The bottom fabric portion 35 is sewn to the side fabric portions 32L, 32S and has an open portion formed in a circular shape at the center, the open portion opening the bottom surface of the inner material 10. A linear elastic body such as rubber body is sewn into a peripheral edge 134 of the open portion. The shape of the open portion is not particularly limited, but is a shape that enables the inner material 10 to be inserted into or removed from the cover body 30C through the open portion.

[0096] The present invention is not limited to the above description of the embodiments and examples of the invention. Various modifications that can be easily conceived by those skilled in the art without departing from the scope of the claims are also included in the present invention.REFERENCE SIGNS LIST

[0097] 1 bed mattress 10 inner material 11, 12, 13 flat portion 15, 16, 17 edge portion 19 corner portion 20, 30A, 30B, 30C cover body 21, 40, 121, 221, 140 corner covering portion 22, 122, 222 variable portion 23, 123, 223 sheet portion 27 reinforcing thread 31 upper fabric portion 32L, 32S side fabric portion 35 bottom fabric portion 41, 141 first side contact portion 42, 142 second side contact portion 43, 143 bottom contact portion 50 corner fabric portion 130 reinforcing sheet

Examples

Embodiment Construction

[0037]Hereinafter, embodiments of the present invention will be described.

[0038]FIG. 1 illustrates an inner material 10 and a cover body 20, FIG. 1A illustrates the inner material 10, FIG. 1B illustrates the cover body 20, and FIG. 1C illustrates a bed mattress 1 in which the inner material 10 is covered with the cover body 20.

[0039]The inner material 10 is a plate-shaped cushion member.

[0040]The cushion member can be arbitrarily selected according to the application and use situation of the bed mattress. For example, a filament three-dimensional conjugate fiber (trade name: Airfiber, manufactured by Airweave Inc.), a polyurethane foam, and the like can be selected. The inner material 10 may be formed of the same material as a whole, or may be formed of different materials (material characteristics, degrees of foaming) in the thickness direction and / or the width direction to adjust hardness and repulsive force.

[0041]The shape of the inner material 10 can be arbitrarily designed acco...

TECHNICAL FIELD

[0001] The present invention relates to an improvement of a cover body for a bed mattress and a method for sewing the same.BACKGROUND ART

[0002] A bed mattress includes an inner material having cushioning properties, and a cover body covering the inner material.

[0003] It is preferable to make the cover body removable from the inner material for ease of washing and the like, and for ease of changing the design.

[0004] Patent Literature 1 is referred to as literature disclosing a technique related to the present invention.CITATIONS LISTPATENT LITERATURE

[0005] Patent Literature 1: JP 2020-81382 ASUMMARY OF INVENTIONTECHNICAL PROBLEMS

[0006] The cushioning properties of the inner material of the bed mattress are adjusted in various ways depending on the aspects of usage required for the bed mattress.

[0007] Here, the following problems have been observed when softness is required for the inner material of the bed mattress.

[0008] In general, to avoid occurrence of wrinkles on the front surface of the cover body, the inner material is tightly and entirely covered with the cover body. At this time, when the inner material of the bed mattress is soft, the inner material is compressed in the thickness direction by the cover body, causing the side surface of the bed mattress to deform. A bed mattress including a plate-shaped inner material is to have flat upper and side surfaces. However, when the inner material is soft, the inner material is compressed by the cover body, and the side surface of the inner material bulges outward or becomes wrinkled, so that the flatness is hindered. As a result, the linearity of an edge portion on the boundary between the upper surface (or the lower surface) and the side surface, or the boundary between the side surfaces, may be impaired at a corner portion of the bed mattress, and the design may not be exhibited as intended.

[0009] By preparing a plurality of pieces of fabric, sewing the edge portions thereof together to form a cover body, and positioning the sewn edge portions to face the edge portion of the inner material, the linearity of the portion of the cover body facing the edge portion can be ensured. However, it takes time and effort to sew the plurality of pieces of fabric together, and when a sewn portion is present at the corner covering portion of the cover body, and the sewn portion faces the corner portion of the inner material, the corner covering portion cannot completely follow the corner portion of the inner material, thereby creating a space therebetween, even if only slightly. This space may impair the design of the corner portion of the bed mattress.

[0010] Ensuring the linearity of a section facing an edge portion of an inner material in a cover body that entirely covers the inner material is also required for a type of cover body that covers the upper surface and the side surfaces of an inner material and leaves the bottom surface open (cf. FIG. 5). This is because, in such a type of cover body main portion 30, a linear elastic body such as rubber is sewn into end edges 34 of side fabric portions 32L, 32S facing the side surfaces of an inner material 10 (edge portions facing the bottom edge of the inner material 10), so that the inner material 10 may be compressed in the thickness direction.

[0011] Such a type of cover body main portion 30 further has a problem of displacement relative to the inner material 10. That is, when a user rolls over in bed, as illustrated in FIG. 5(B), the cover body main portion 30 may be displaced as the user moves. If the elastic force of the linear elastic body at the end edge 34 is increased to prevent displacement, the compressive force in the thickness direction of the inner material 10 increases and the deformation of the inner material 10 is promoted, so that a certain limitation is imposed on the elastic force of the linear elastic body.SOLUTIONS TO PROBLEMS

[0012] The present invention has been made to solve the above problems, and a first aspect thereof is defined as follows. That is, a cover body that entirely covers an inner material of a bed mattress, in which a corner portion of the inner material includes a pair of flat portions arranged vertically and an edge portion between the pair of flat portions, the cover body includes a corner covering portion covering the corner portion of the inner material, the corner covering portion includes a continuous fabric, and the corner covering portion includes a variable portion facing the edge portion of the inner material and a sheet portion facing each of the flat portions, and the variable portion has a shape-retaining property lower than that of the sheet portion.

[0013] According to the cover body defined as above, by positioning the variable portion of the corner covering portion to face the edge portion of the corner portion of the inner material and positioning the sheet portion of the corner covering portion to face the flat portion of the inner material, the corner covering portion can face the inner material along the corner portion of the inner material without a gap. This is caused by the following: a space is unlikely to be formed between the cover body and the inner material because the corner covering portion is formed of a continuous fabric; and / or the variable portion facing the edge portion of the inner material deforms preferentially due to having a small shape-retaining property. In other words, the stress of the cover body concentrates on the variable portion, thereby suppressing the deformation of the sheet portion.

[0014] Since the deformation of the sheet portion is suppressed in the corner covering portion of the cover body, the deformation of the side surfaces, the upper surface, and the lower surface of the bed mattress is suppressed, and the flatness thereof is maintained. Since the deformation of the side surfaces, the upper surface, and the lower surface of the mattress is suppressed, the linearity of the edge portion connecting the respective flat surfaces is also maintained.

[0015] The deformation of the corner covering portion concentrates on the variable portion having a small shape-retaining property. In other words, even if the variable portion having a small shape-retaining property deforms, this does not cause deformation of the edge portion of the inner material, and the variable portion rather deforms along the edge portion. Thus, the linearity of the edge portion of the inner material is maintained.

[0016] A cover body defined in a second aspect of the present invention is defined as follows.

[0017] In the cover body defined in the first aspect, a part of the continuous fabric is folded and sewn in the sheet portion of the corner covering portion.

[0018] According to the cover body of the second aspect defined as above, the fabric is folded and sewn, thereby increasing the shape-retaining property of the sheet portion. Since the fabric constitutes the corner covering portion including the deformation portion, the number of components of the cover body can be minimized. This enables a reduction in the manufacturing cost of the cover body.

[0019] A cover body defined in a third aspect of the present invention is defined as follows.

[0020] In the cover body defined in the first aspect, the sheet portion of the corner portion is reinforced by another member.

[0021] According to the cover body of the third aspect defined as above, the shape-retaining property can be increased by reinforcing the sheet portion with another member. The degree of reinforcement of the sheet portion can be arbitrarily adjusted by selecting material characteristics or the like of another member.

[0022] When the cover body is of a type that covers the upper surface and the side surfaces of the inner material and leaves the bottom surface open, another aspect (sixth aspect) of the present invention is defined as follows. That is, a cover body covering an upper surface and side surfaces of an inner material of a bed mattress, and leaving a bottom surface of the inner material open, in which a corner portion of the inner material includes a pair of the side surfaces arranged vertically and an edge portion between the pair of side surfaces, the cover body includes a corner covering portion covering the corner portion of the inner material, and the corner covering portion includes a variable portion facing the edge portion of the inner material, a first side contact portion and a second side contact portion facing the respective side surfaces of the pair of side surfaces, and a bottom contact portion facing the bottom surface of the inner material, and the variable portion has a shape-retaining property lower than those of the first side contact portion and the second side contact portion.

[0023] According to the cover body of the sixth aspect defined as above, the linearity of the section facing the edge portion is ensured by the presence of the variable portion. Furthermore, even if a force is applied to the upper surface of the cover body with movement of a user, the bottom contact portion provided in the corner covering portion contacts the bottom surface of the inner material, and the movement is suppressed. Accordingly, displacement of the cover body relative to the inner material does not occur.

[0024] The variable portion of the cover body as described above can be configured as follows (seventh aspect).

[0025] That is, the first side contact portion and the second side contact portion are connected by the bottom contact portion, and the variable portion is formed by opening a portion facing the edge portion or by bringing edges into an unconnected state, the edges facing each other in the first side contact portion and the second side contact portion.

[0026] An eighth aspect of the present invention is defined as follows. That is, the cover body defined in the sixth aspect further includes: an upper fabric portion facing the upper surface of the inner material; a side fabric portion facing each of the side surfaces of the inner material; and a corner fabric portion constituting the corner covering portion.

[0027] In the cover body of the eighth aspect defined as above, since the three fabric portions, which are the upper fabric portion, the side fabric portion, and the corner fabric portion, are independent, the degree of freedom in designing each fabric portion is improved.

[0028] Note that a part of the upper fabric portion and a part of the side fabric portion can be made of the same continuous fabric.

[0029] A ninth aspect of the present invention is defined as follows. That is, in the cover body defined in the eighth aspect, in the corner fabric portion, fabric of each of the first side contact portion and the second side contact portion has a shape-retaining property higher than that of fabric of the side fabric portion.

[0030] According to the cover body of the eighth aspect defined as above, in the fabric facing the side surface of the inner material, the shape-retaining properties of the first and second side contact portions of the corner fabric portion are enhanced. This makes it possible to suppress deformation of the inner material due to compression.

[0031] A measure for enhancing the shape-retaining properties of the first and second side contact portions of the corner fabric portion is arbitrary, but for example, as defined in a tenth aspect, superimposing the corner fabric portion on the side fabric portion can be employed. When such a measure is employed, the rigidity of the superimposed portion formed by the side fabric portion and each of the first and second side contact portions increases, thereby enhancing the shape-retaining property thereof. The superimposed portion is sewn by stitching, thereby enabling further improvement in the shape-retaining property. A reinforcing sheet can also be applied to the superimposed portion.

[0032] Each of the first and second side contact portions of the corner fabric portion may be continuously coupled to the side fabric portions. In this case, the shape-retaining property can be improved by applying the reinforcing sheet to each of the first and second side contact portions.

[0033] As long as the reinforcing sheet is made of a material having rigidity higher than that of the side fabric portion, the material characteristics of the reinforcing sheet are not particularly limited. A thin plate of a flexible polymeric material such as a foam material can be employed.

[0034] Another aspect (thirteenth aspect) of the present invention is defined as follows. That is, a cover body covering an upper surface and side surfaces of an inner material of a bed mattress, and leaving a bottom surface of the inner material open, in which a corner portion of the inner material includes a pair of the side surfaces arranged vertically and an edge portion between the pair of side surfaces, the cover body includes a single piece of original fabric including an upper fabric portion facing the upper surface of the inner material, side fabric portions facing the side surfaces, and a corner fabric portion facing the corner portion, the side fabric portions, continuous with respective sides of the upper fabric portion formed in a rectangular shape in the original fabric, are arranged such that adjacent ones of the side fabric portions are orthogonal to each other, and in the corner fabric portion, a ridge line disposed between the adjacent side fabric portions and directed outward from a corner part of the upper fabric portion is folded in a mountain fold along an edge portion of the corner portion, and the ridge line folded in the mountain fold serves as a variable portion, and in the corner fabric portion, a folded portion excluding the ridge line is sewn to have a shape-retaining property higher than that of the variable portion.

[0035] According to the cover body of the thirteenth aspect defined as above, an action similar to that of the cover body defined in the first aspect is exerted. Furthermore, since the cover body is formed from a single piece of original fabric, effective use of fabric is promoted, and cost reduction can be achieved.BRIEF DESCRIPTION OF DRAWINGS

[0036] FIG. 1 is a schematic view illustrating a relationship between an inner material and a cover body. FIG. 2 is a schematic view illustrating a state in which the inner material is covered with the cover body according to an embodiment of the present invention. FIG. 3 is a schematic view illustrating a state in which the inner material is covered with a cover body according to another embodiment of the present invention. FIG. 4 is a schematic view illustrating a cover body according to another embodiment of the present invention and a state in which the inner material is covered with the cover body. FIG. 5(A) illustrates an exploded perspective view of a conventional inner material and a cover body covering the upper surface and the side surfaces of the inner material and leaving the bottom surface open, and FIG. 5(B) illustrates a schematic view illustrating displacement of the cover body relative to the inner material. FIG. 6 illustrates a cover body of another embodiment that covers the inner material, FIG. 6(A) illustrates a top-side perspective view, and FIG. 6(B) illustrates a bottom-side perspective view. FIG. 7 illustrates a corner covering portion that is applied to the cover body of FIG. 6, FIG. 7(A) illustrates a back-side perspective view, and FIG. 7(B) illustrates a developed view. FIG. 8 illustrates a cover body according to another embodiment of the present invention, FIG. 8(A) illustrates a top-side perspective view, and FIG. 8(B) illustrates a developed view. FIG. 9 is a bottom-side perspective view of a state in which the inner material is covered with the cover body of FIG. 8, and a corner covering portion of another embodiment is applied. FIG. 10 illustrates a corner covering portion of another embodiment, FIG. 10(A) illustrates a back-side perspective view, and FIG. 10(B) illustrates a developed view. FIG. 11 is a bottom-side perspective view illustrating an example of a cover body including a bottom fabric portion. DESCRIPTION OF EMBODIMENTS

[0037] Hereinafter, embodiments of the present invention will be described.

[0038] FIG. 1 illustrates an inner material 10 and a cover body 20, FIG. 1A illustrates the inner material 10, FIG. 1B illustrates the cover body 20, and FIG. 1C illustrates a bed mattress 1 in which the inner material 10 is covered with the cover body 20.

[0039] The inner material 10 is a plate-shaped cushion member.

[0040] The cushion member can be arbitrarily selected according to the application and use situation of the bed mattress. For example, a filament three-dimensional conjugate fiber (trade name: Airfiber, manufactured by Airweave Inc.), a polyurethane foam, and the like can be selected. The inner material 10 may be formed of the same material as a whole, or may be formed of different materials (material characteristics, degrees of foaming) in the thickness direction and / or the width direction to adjust hardness and repulsive force.

[0041] The shape of the inner material 10 can be arbitrarily designed according to the bed serving as a base, but is generally a rectangular thin plate shape.

[0042] Therefore, the inner material 10 includes an upper surface (flat surface 11) and side surfaces (flat portions 12, 13) orthogonal to each other, the adjacent flat portions include an edge portion 15 linear in the vertical direction, and the flat portions 12, 13 adjacent to the flat surface 11 include edge portions 16, 17 linear in the horizontal direction. At least a pair of flat portions and the edge portion form a corner portion. For example, the flat portion 12, the flat portion 13, and the edge portion 15 form a corner portion 19.

[0043] In this example, as the inner material 10, a filament three-dimensional conjugate fiber having a height of 10 to 600 mm, a width of 300 to 2500 mm, and a length of 1000 to 2500 mm is employed.

[0044] The cover body 20 is made of fabric and is a bag body having the same outer diameter dimension as the outer dimension of the inner material 10. One side can be opened and closed by a linear fastener to accommodate the inner material 10.

[0045] Reference numeral 21 in the figure denotes a corner covering portion, which faces the corner portion of the inner material 10.

[0046] In the following description, attention will be paid to the corner covering portion 21 and the corner portion 19, where the side surface (flat portion 12) and the side surface (flat portion 13) are connected by the edge portion 15 in the inner material 10.

[0047] FIG. 2A illustrates a detailed configuration of the corner covering portion 21 of the cover body 20.

[0048] The corner covering portion 21 is made of a single piece of fabric 25 and includes a variable portion 22 and sheet portions 23.

[0049] The variable portion 22 is sandwiched by the sheet portions 23, and the fabric 25 is not folded in any way in the variable portion 22 and is formed as a single piece. In the sheet portion 23, the fabric 25 is folded downward from the variable portion 22, and the folding is triple and sewn with reinforcing thread 27.

[0050] According to the corner covering portion 21 configured as described above, the fabric 25 is continuous on the design surface (uppermost surface). Therefore, the corner covering portion 21 can be provided with a unique design. For example, it is easy to form a pattern on the corner covering portion 21.

[0051] In the example of FIG. 2(B), the end edge of the sheet portion 23 (the edge opposite to the variable portion 22) extends to the middle of each of the flat portion 12 and the flat portion 13. If the corner covering portion 21 of the cover body 20 exhibits its function and does not cause any deformation of the corner portion 19 of the inner material 10 to follow its original shape, the design as a bed mattress is not impaired.

[0052] Naturally, the sheet portion of the cover body 20 may be provided to face the entire surface of the flat portion 12 and the entire surface of the flat portion 13 of the inner material 10, or the relatively short sheet portion 23 illustrated in FIG. 2(A) may be repeatedly arranged.

[0053] The degree of folding (superimposition) of the fabric 25 in the sheet portion 23 is arbitrarily selected according to the shape-retaining property required for the sheet portion 23 in consideration of the bending property of the fabric 25 itself, the density of sewing, and the like. To pull out the end edge of the fabric 25 from the sheet portion 23, folding is performed an odd number of times of 3 or more.

[0054] As long as a sufficient shape-retaining property can be ensured for the sheet portion 23, the density of sewing can also be arbitrarily selected.

[0055] The sewing pattern is arbitrary, and a general-purpose stitch pattern can be employed to provide any design to the sheet portion 23.

[0056] The color and thickness of the reinforcing thread 27 are also arbitrarily selected. Sewing the sheet portion 23 with one reinforcing thread 27 is preferable from the viewpoint of ease of sewing, but the fabric of one sheet portion 23 may also be sewn using a plurality of reinforcing threads 27, each having a different color or stitch pattern.

[0057] The cover body 20 illustrated in FIG. 2 can be formed as follows.

[0058] A continuous fabric 25 is prepared. The width of the fabric 25 is three times or more the total width of the flat portions 12, 13 of the inner material 10.

[0059] Next, a portion facing the edge portion of the inner material 10, that is, the variable portion 22, is defined. At this time, the fabric is provided on both sides of the variable portion 22, with widths equal to or greater than three times the widths of the flat portion 12 and the flat portion 13, respectively.

[0060] Next, the portion of the fabric 25 on each side of the variable portion 22 is folded in a triple manner and temporarily secured with a needle, a tape, or the like.

[0061] The folded portion is sewn by stitching.

[0062] In the cover body 20 formed in this manner, the shape-retaining property of the variable portion 22, in which the fabric 25 is a single piece, is lower than the shape-retaining property of the sheet portion 23, in which the fabric 25 is folded in a triple manner and reinforced by stitching.

[0063] As a result, when the inner material 10 is tightly covered with the cover body 20, the variable portion of the corner covering portion of the cover body deforms along the edge portion of the inner material 10 to maintain the linearity, and the sheet portion having the high shape-retaining property faces the flat portion of the inner material to maintain the flatness.

[0064] FIG. 3 illustrates a corner covering portion 121 of a cover body according to another embodiment. Note that the same elements as those in FIG. 2 are denoted by the same reference numerals, and the description thereof will be omitted.

[0065] The corner covering portion 121 has a structure in which a variable portion 122 is sandwiched between sheet portions 123, 123, and the sheet portions 123, 123 and the variable portion 122 are connected by a continuous fabric 25. A reinforcing sheet 130 is attached to the back surface (the surface facing the inner material 10) of the sheet portion 123 to make the shape-retaining property of the sheet portion 123 higher than that of the variable portion 122.

[0066] By attaching the reinforcing sheet 130 to the back surface of the sheet portion 123, the continuous fabric 25 is exposed in a plain state on the front surface of the corner covering portion 121. This provides simple design to the corner covering portion 121.

[0067] In the above example, the reinforcing sheet 130 is attached to the back surface of the sheet portion 123, but a bag can be provided in the sheet portion 123, and the reinforcing sheet can be inserted into the bag. It is not avoided to sew the reinforcing sheet 130 to the fabric of the sheet portion 123.

[0068] As long as the material of the reinforcing sheet 130 has higher rigidity than that of the fabric 25, the material characteristics of the reinforcing sheet 130 are not particularly limited. A thin plate of a flexible polymeric material such as a foam material can be employed.

[0069] FIG. 4 illustrates a corner covering portion 221 of a cover body of another embodiment. Note that the same elements as those in FIG. 2 are denoted by the same reference numerals, and the description thereof will be omitted.

[0070] The corner covering portion 221 has a structure in which a variable portion 222 is sandwiched between sheet portions 223, 223, and the sheet portions 223, 223 and the variable portion 222 are connected by a continuous fabric 25.

[0071] In this example, a short second folded portion 2231 is provided at a portion connected to the variable portion 222 in the sheet portion 223. Although the fabric 25 is also folded in the second folded portion 2231, the density of sewing with the reinforcing thread 27 is smaller than that of a main body portion 2233 of the variable portion 222, and the shape-retaining property is between those of the main body portion 2233 and the variable portion 222.

[0072] This enables smooth deformation between the variable portion 222 and the sheet portion 223.

[0073] By providing the second folded portion 2231, the width of the variable portion 222 can be further narrowed.

[0074] The width of the second folded portion 2231 is not particularly limited, but can be the same as or twice the width of the variable portion 222.

[0075] FIG. 6 illustrates a cover body 30A of another example.

[0076] The cover body 30A has a configuration in which a corner covering portion 40 is superimposed on the conventional cover body main portion 30. Note that the same elements as those in FIGS. 1 and 5 are denoted by the same reference numerals, and the description thereof will be omitted.

[0077] The cover body main portion 30 includes an upper fabric portion 31 and side fabric portions 32L, 32S. In this example, the long belt-shaped side fabric portion 32L and the short belt-shaped side fabric portion 32S are prepared, and one edge of each of those portions is sewn to the peripheral edge of the rectangular upper fabric portion 31 to form the bottomless box type cover body main portion 30. At this time, the facing edges of the side fabric portion 32L and the side fabric portion 32S may or may not be sewn together.

[0078] A corner fabric portion cut out in the developed view illustrated in FIG. 7(B) is bent along dotted lines to form the three-dimensional corner covering portion 40 illustrated in FIG. 7(A). A first side contact portion 41 and a second side contact portion 42 are superimposed on the side fabric portion 32L and the side fabric portion 32S, respectively, and are sewn at a fine pitch by stitching. In this example, an inner edge 411 of the first side contact portion 41 and an inner edge 412 of the second side contact portion 42 are sewn together.

[0079] In such a state, the shape-retaining properties of the first side contact portion 41 and the second side contact portion 42, which are superimposed on and sewn to the side fabric portion 32S and the side fabric portion 32L, respectively, are higher than the shape-retaining property of the connection portion between the inner edge 411 of the first side contact portion 41 and the inner edge 412 of the second side contact portion 42. A linear section obtained by sewing the inner edge 411 of the first side contact portion 41 and the inner edge 412 of the second side contact portion 42 is a variable portion facing the edge portion 15 of the inner material 10.

[0080] When the facing end edges of the side fabric portion 32L and the side fabric portion 32S are connected, the sewing of the inner edge 411 of the first side contact portion 41 and the inner edge 412 of the second side contact portion 42 can be omitted.

[0081] A material for forming the corner covering portion 40 is not particularly limited, but is preferably the same as, or the same type of fabric material as, that for the cover body main portion 30.

[0082] The widths of the first side contact portion 41 and the second side contact portion 42 are preferably equal to each other, but the widths may be different from each other. The widths can be 1 / 4 to 1 / 1 of the thickness of the inner material 10.

[0083] According to the cover body 30A configured as described above, bottom contact portions 43 of the corner covering portion 40 arranged at the respective corner portions of the inner material 10 contact the bottom surface of the inner material 10. Therefore, even when a force parallel to the upper surface of the inner material 10 is applied, the cover body 30A is not displaced relative to the inner material 10.

[0084] Furthermore, the shape-retaining properties of the first side contact portion 41 and the second side contact portion 42 are higher than the shape-retaining property of the linear section (variable portion) in which the inner edge 411 of the first side contact portion 41 and the inner edge 422 of the second side contact portion 42 contact each other. Therefore, the variable portion easily follows the edge portion 15 of the inner material 10 and its linearity can be ensured, and even if the cover body 30A compresses the inner material 10, the shape of the side surface can be prevented from collapsing.

[0085] FIG. 8 illustrates a cover body 30B of another embodiment. In FIG. 8, the same elements as those in FIG. 6 are denoted by the same reference numerals, and the description thereof will be omitted.

[0086] The cover body 30B is formed from a single piece of fabric (original fabric) illustrated in FIG. 8(B). The original fabric includes a rectangular upper fabric portion 31, side fabric portions 32L, 32S, and a corner fabric portion 50.

[0087] The long band-shaped side fabric portions 32L, 32L are continuous with a pair of long edges of the upper fabric portion 31, and the short band-shaped side fabric portions 32S, 32S are continuous with a pair of short edges of the upper fabric portion 31.

[0088] The corner fabric portion 50 has a fan shape and is continuously formed between the side fabric portion 32L and the side fabric portion 32S. The corner fabric portion 50 is also continuous with a corner part of the upper fabric portion 31.

[0089] The corner fabric portion 50 is folded as follows. A ridge line 51, which extends outward from the corner part of the upper fabric portion 31 and divides the corner fabric portion 50 into two parts, is folded into a mountain fold. A ridge line 53, which divides a portion between the ridge line 51 and each of the ridge lines 55, 55 defining the end edges of the side fabric portion 32L and the side fabric portion 32S into two parts, is folded into a valley fold. The ridge lines 51, 55 are then brought into alignment. By sewing the superimposed fabric portions in this state, a bottomless box-shaped cover body 30B is formed as illustrated in FIG. 8(A).

[0090] FIG. 9 illustrates a state in which the inner material 10 is covered with the cover body 30B of FIG. 8. In this example, a corner covering portion 140 is attached to each corner part of the cover body 30B (cf. FIG. 10). The attachment is performed by sewing a first side contact portion 141 and a second side contact portion 142 to the side fabric portion 32L and the side fabric portion 32S, respectively.

[0091] In the corner covering portion 140, the first side contact portion 141 and the second side contact portion 142 are connected by a bottom contact portion 143. An inner edge 1411 of the first side contact portion 141 and an inner edge 1421 of the second side contact portion 142 are separated from each other.

[0092] According to the corner covering portion 140 configured in this manner, compared to the corner covering portion 40 in FIG. 7, the bottom contact portion 143 is shifted to the center side as viewed from the corner part of the inner material 10 and has a larger area, so that the cover body 30B is less likely to be displaced relative to the inner material 10.

[0093] In the corner covering portion 140, a space portion between the first side contact portion 141 and the second side contact portion 142 constitutes a variable portion.

[0094] FIG. 11 illustrates a cover body 30C of another embodiment. In FIG. 11, the same elements as those in FIG. 6 are denoted by the same reference numerals, and the description thereof will be omitted.

[0095] The cover body 30C includes a bottom fabric portion 35. The bottom fabric portion 35 is sewn to the side fabric portions 32L, 32S and has an open portion formed in a circular shape at the center, the open portion opening the bottom surface of the inner material 10. A linear elastic body such as rubber body is sewn into a peripheral edge 134 of the open portion. The shape of the open portion is not particularly limited, but is a shape that enables the inner material 10 to be inserted into or removed from the cover body 30C through the open portion.

[0096] The present invention is not limited to the above description of the embodiments and examples of the invention. Various modifications that can be easily conceived by those skilled in the art without departing from the scope of the claims are also included in the present invention.REFERENCE SIGNS LIST

[0097] 1 bed mattress 10 inner material 11, 12, 13 flat portion 15, 16, 17 edge portion 19 corner portion 20, 30A, 30B, 30C cover body 21, 40, 121, 221, 140 corner covering portion 22, 122, 222 variable portion 23, 123, 223 sheet portion 27 reinforcing thread 31 upper fabric portion 32L, 32S side fabric portion 35 bottom fabric portion 41, 141 first side contact portion 42, 142 second side contact portion 43, 143 bottom contact portion 50 corner fabric portion 130 reinforcing sheet

Examples

Embodiment Construction

[0037]Hereinafter, embodiments of the present invention will be described.

[0038]FIG. 1 illustrates an inner material 10 and a cover body 20, FIG. 1A illustrates the inner material 10, FIG. 1B illustrates the cover body 20, and FIG. 1C illustrates a bed mattress 1 in which the inner material 10 is covered with the cover body 20.

[0039]The inner material 10 is a plate-shaped cushion member.

[0040]The cushion member can be arbitrarily selected according to the application and use situation of the bed mattress. For example, a filament three-dimensional conjugate fiber (trade name: Airfiber, manufactured by Airweave Inc.), a polyurethane foam, and the like can be selected. The inner material 10 may be formed of the same material as a whole, or may be formed of different materials (material characteristics, degrees of foaming) in the thickness direction and / or the width direction to adjust hardness and repulsive force.

[0041]The shape of the inner material 10 can be arbitrarily designed acco...

Claims

1. A cover body that entirely covers an inner material of a bed mattress, wherein a corner portion of the inner material includes a pair of flat portions arranged vertically and an edge portion between the pair of flat portions, the cover body comprises a corner covering portion covering the corner portion of the inner material, the corner covering portion includes a continuous fabric, and the corner covering portion includes a variable portion facing the edge portion of the inner material and a sheet portion facing each of the flat portions, and the variable portion has a shape-retaining property lower than that of the sheet portion.

2. The cover body according to claim 1, wherein a part of the continuous fabric is folded and sewn in the sheet portion of the corner covering portion.

3. The cover body according to claim 1, wherein the sheet portion of the corner portion is reinforced by another member.

4. A bed mattress, wherein the inner material is covered with the cover body according to claim 1.

5. A method for manufacturing the cover body according to claim 2, the method comprising: preparing the continuous fabric; defining, in the continuous fabric, a variable portion facing the edge portion of the inner material; folding a portion at each end of the variable portion in the continuous fabric; and sewing the folded portion.

6. A cover body covering an upper surface and side surfaces of an inner material of a bed mattress, and leaving a bottom surface of the inner material open, wherein a corner portion of the inner material includes a pair of the side surfaces arranged vertically and an edge portion between the pair of side surfaces, the cover body comprises a corner covering portion covering the corner portion of the inner material, and the corner covering portion includes a variable portion facing the edge portion of the inner material, a first side contact portion and a second side contact portion facing the respective side surfaces of the pair of side surfaces, and a bottom contact portion facing the bottom surface of the inner material, and the variable portion has a shape-retaining property lower than those of the first side contact portion and the second side contact portion.

7. The cover body according to claim 6, wherein the first side contact portion and the second side contact portion are connected by the bottom contact portion, and the variable portion is formed by opening a portion facing the edge portion or by bringing edges into an unconnected state, the edges facing each other in the first side contact portion and the second side contact portion.

8. The cover body according to claim 6, further comprising an upper fabric portion facing the upper surface of the inner material; a side fabric portion facing each of the side surfaces of the inner material; and a corner fabric portion constituting the corner covering portion.

9. The cover body according to claim 8, wherein, in the corner fabric portion, fabric of each of the first side contact portion and the second side contact portion has a higher shape-retaining property than fabric of the side fabric portion.

10. The cover body according to claim 8, wherein the corner fabric portion is superimposed on the side fabric portion.

11. The cover body according to claim 8, wherein, in the side fabric portion, a linear elastic body is attached to an edge portion facing a bottom edge of the inner material.

12. The cover body according to claim 8, further comprising a bottom fabric portion including an open portion that opens a part of the bottom surface of the inner material, wherein a linear elastic body is attached to a peripheral edge of the open portion of the bottom fabric portion.

13. A cover body covering an upper surface and side surfaces of an inner material of a bed mattress, and leaving a bottom surface of the inner material open, wherein a corner portion of the inner material includes a pair of the side surfaces arranged vertically and an edge portion between the pair of side surfaces, the cover body comprises a single piece of original fabric including an upper fabric portion facing the upper surface of the inner material, side fabric portions facing the side surfaces, and a corner fabric portion facing the corner portion, the side fabric portions, continuous with respective sides of the upper fabric portion formed in a rectangular shape in the original fabric, are arranged such that adjacent ones of the side fabric portions are orthogonal to each other, and in the corner fabric portion, a ridge line disposed between the adjacent side fabric portions and directed outward from a corner part of the upper fabric portion is folded in a mountain fold along an edge portion of the corner portion, and the ridge line folded in the mountain fold serves as a variable portion, and in the corner fabric portion, a folded portion excluding the ridge line is sewn to have a shape-retaining property higher than that of the variable portion.

Images