Support structure for cantilevered staircase

Abstract

To provide a cantilevered staircase with improved safety.SOLUTION: A support structure for a cantilevered staircase comprises a tread and a lower support that supports the tread from below, and it comprises a fixing member that is positioned vertically above and below one end side of the tread and the lower support, respectively, and that sandwiches and fixes the tread and the lower support.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a support structure for a cantilevered staircase. [Background technology]

[0002] Conventionally, cantilevered stairs are known in which one end of the treads that make up the stairs is fixed and supported by a structure such as a pillar (see, for example, Patent Document 1). The cantilevered stairs are selected as an ascending and descending structure based on the structural and design requirements of the building. The amount of deflection of stair treads is regulated by the Quality Housing Components (BL Components) Certification System. However, there are no regulations regarding safety, and strength calculations are required to ensure safety. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-275404 A Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Document 1 discloses a technique for inserting a fastener into a hole formed on the side of the step plate and fixing it to the frame. However, depending on the thickness and material of the step plate, such a support structure may not be strong enough. Therefore, it is considered to provide a separate support member that supports the step plate from below. When the step plate and the support member are made of different materials, it is difficult to fix the step plate and the support member with fasteners or the like depending on the combination of materials. In this case, the step plate and the support member are joined by adhesion, welding, or the like. In this case, the joint between the step plate and the support member may come off.

[0005] The present disclosure has been made in consideration of the above, and aims to provide a cantilevered staircase with improved safety. [Means for solving the problem]

[0006] The present disclosure relates to a support structure for a cantilever staircase comprising a step and a lower support that supports the step from below, the support structure comprising fixing members that are respectively arranged vertically above and vertically below one end side of the step and the lower support, and that clamp and fix the step and the lower support. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a perspective view showing the support structure of the cantilever staircase according to the first embodiment. [Diagram 2] FIG. 2 is a side view showing the support structure of the cantilever staircase according to the first embodiment. [Diagram 3] FIG. 2 is a bottom view showing the support structure of the cantilever staircase according to the first embodiment. [Figure 4] FIG. 2 is an enlarged bottom view of one end side of the footboard according to the first embodiment. [Diagram 5] FIG. 2 is a side view showing the fixing member according to the first embodiment. [Figure 6] FIG. 11 is a side view showing a fixing member according to the second embodiment. [Figure 7] FIG. 1 is a conceptual side view showing the relationship between a cantilevered staircase and a user's field of view. [Figure 8] FIG. 1 is a conceptual side view showing the relationship between a cantilevered staircase and a user's field of view. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] As shown in Figs. 1 to 3, the support structure 100 for the cantilevered staircase according to this embodiment includes a step 10, a lower support 20 that supports the step 10 from below, and a pair of fixing members 31 and 32 that clamp and fix one end of the step 10 and the lower support 20. In the following description, the frame 40 to which the step 10 is fixed is described as a pillar. On the other hand, the object to which the step 10 is fixed is not limited to a pillar, and it is sufficient if it has a predetermined strength or more that can support at least the weight of a user of the cantilevered staircase. The object may be, for example, a beam or girder. In each drawing, the longitudinal direction (width direction) of the step 10 is shown as the X direction, the lateral direction (front-rear direction) of the step 10 is shown as the Y direction, and the vertical direction (thickness direction) is shown as the Z direction.

[0009] (Stepping board) As shown in Figs. 2 and 3, the step 10 is a plate-like member having a length L1X in the X direction, a length L1Y in the Y direction, and a length (thickness) L1Z in the Z direction. The step 10 has a uniform thickness, and the thickness L1Z is preferably 30 mm or less. From the viewpoint of ensuring safety as a residential staircase, the length L1X is preferably 750 mm or more. In Figs. 2 and 3, the step 10 is shown as a substantially rectangular step, but the shape of the step 10 is not limited to a rectangular shape. When the shape of the step 10 is not rectangular, the length L1X in the X direction, the length L1Y in the Y direction, and the length (thickness) L1Z in the Z direction in this specification each refer to the maximum length.

[0010] The step 10 is preferably made of, for example, fiber reinforced plastic, and more preferably made of carbon fiber reinforced plastic (hereinafter, "CFRP"). This is because the cantilever staircase support structure 100 according to this embodiment can be preferably applied to point loads and materials with low compressive strength. On the other hand, the material constituting the step 10 is not limited to the above. The step 10 may be made of wood, glass, steel, etc.

[0011] When the step board 10 is made of CFRP, the CFRP is not particularly limited, but it is preferable that the carbon fiber constituting the CFRP has a Young's modulus (tensile elastic modulus) of 500 GPa or more and a tensile strength of 2000 MPa or more. An example of the carbon fiber is a pitch-based carbon fiber. This can reduce the amount of deflection of the step board 10 even if the thickness L1Z of the step board 10 is 30 mm or less.

[0012] The step board 10 is obtained, for example, by overlapping and bonding CFRP prepreg sheets. The CFRP prepreg sheet is a sheet in which carbon fibers are uniformly impregnated with a matrix resin such as a thermosetting resin or a thermoplastic resin. The CFRP prepreg sheet is preferably one in which the carbon fibers are aligned in a predetermined direction. The step board 10 is preferably configured so that the predetermined direction in which the fibers are oriented is along the X direction of the step board 10. The predetermined direction and the X direction of the step board 10 are preferably approximately parallel, but may have a certain angle. Specifically, the angle between the predetermined direction and the X direction of the step board 10 is preferably 0° or more and less than 45°.

[0013] At one end of the footboard 10 in the X direction (the end toward the pillar 40), holes are formed on both ends in the Y direction. The holes are arranged so as to communicate with holes h1 formed in the fixing members 31 and 32.

[0014] (lower support) The lower support 20 supports the footboard 10 from below. The lower support 20 abuts against and supports the footboard 10, and is fixed directly or indirectly to the column 40. In this embodiment, the lower support 20 includes a support plate 21 and a rib 22, as shown in Figs. 1 to 3.

[0015] As shown in Figs. 2 and 3, the support plate 21 is a plate-like member having a length L2X in the X direction, a length L2Y in the Y direction, and a length (thickness) L2Za in the Z direction. The main surface of the support plate 21 abuts against the underside of the footboard 10. The support plate 21 and the footboard 10 are bonded, for example, with an adhesive or the like. The support plate 21 extends from one end side (the column 40 side) of the footboard 10 to the other end side. The material constituting the support plate 21 is not particularly limited, but is preferably a metal material. Examples of metal materials include steel and the like. The shape of the support plate 21 is not limited to a rectangular shape as shown in Figs. 2 and 3. When the shape of the support plate 21 is not rectangular, the length L2X in the X direction, the length L2Y in the Y direction, and the length (thickness) L2Za in the Z direction each refer to the maximum length.

[0016] The rib 22 is a component that is joined to the underside of the support plate 21 by welding or the like, and is disposed so as to protrude below the footboard 10. The maximum length of the rib 22 in the Z direction is L2Zb. By providing the rib 22 on the support plate 21, the amount of deflection of the footboard 10 can be further reduced. The rib 22 may be formed integrally with the support plate 21, or may be formed separately from the support plate 21 and joined to the support plate 21 by welding or the like.

[0017] As shown in Fig. 3, the rib 22 is preferably disposed in the center of the support plate 21 in the Y direction. The rib 22 is preferably inclined so that the length in the thickness direction Z tapers from the pillar 40 side toward the tip side of the footboard 10. The reason for this will be described later, but with the above configuration, the rib 22 can be disposed so as to be difficult to see, thereby improving the design.

[0018] A hole portion extending from one end side to the other end side in the X direction is formed in an end portion of one end side (pillar 40 side) of the rib 22 in the X direction. The hole portion is disposed so as to communicate with a hole portion h2 formed in the fixing member 32.

[0019] The support plate 21 is required to have a certain strength to suppress the bending of the tread 10. On the other hand, by configuring the support plate 21 to be difficult to see, the design of the cantilever staircase support structure 100 can be improved. The configuration of such a support plate 21 that is difficult to see will be described below with reference to the conceptual diagrams of Figures 7 and 8.

[0020] FIG. 7 is a side view showing a schematic relationship between the lines of sight V1-V3 of a person M ascending or descending stairs and a blind spot area R1 below the step. The lines of sight V1-V3 can be set taking into consideration the eye level. For example, in FIG. 7, the angles between the lines of sight V1-V3 and the horizontal direction (Y direction) are V1: 51.1°, V2: 32.6°, and V3: 16.8°, respectively. The height H1 of the lines of sight of person M can be set taking into consideration the average height of Japanese people, and can be set to, for example, 1400 mm.

[0021] In FIG. 7, there is no gap between adjacent step boards in the Y direction. There is a gap H2 between the top surfaces of the step boards in the Z direction. The gap H2 is, for example, 190 mm. The thickness L1Z of the step board is, for example, 30 mm. Under the above conditions, among the step boards 10a, 10b, and 10c whose lower areas may be in the field of view of the person M, the lower area R1 of the step board 10c arranged at the top is the smallest area of ​​the blind spot of the person M under the step boards. Therefore, by arranging the support plate 21 so that it is within the area R1 as much as possible, it is possible to make the support plate 21 difficult to see. The height H3 of the area R1 is about 32 mm under the above conditions.

[0022] Fig. 8 is a side view showing a schematic relationship between the line of sight V of a person M standing beside the stairs and viewing the step 10 from the side, and the blind spot area R2 below the step. The line of sight V can be set taking into consideration the eye level. For example, in Fig. 8, the angle between the line of sight V and the horizontal direction (Y direction) is V: 2.9°.

[0023] In FIG. 8, the distance LX between the step board 10 and person M is, for example, 2000 mm. The height H1 of the line of sight of person M is, for example, 1400 mm, similar to FIG. 7. The length L1X of the step board 10 in the X direction is, for example, 750 mm. The thickness L1Z of the step board 10 is, for example, 30 mm. For example, under the above conditions, an area R2 that is difficult for person M to see is determined. The height H4 of area R2 is approximately 37 mm under the above conditions.

[0024] The support plate 21 is preferably disposed so as to be included in at least one of the regions R1 and R2, and more preferably disposed so as to be included in both the regions R1 and R2. Under the conditions of Fig. 7 and Fig. 8, the height H3 is approximately 32 mm, which is smaller than the height H4. Therefore, the thickness (length in the Z direction) of the support plate 21 is preferably within 32 mm.

[0025] In the conditions of FIG. 7 and FIG. 8, if the thickness L2Za of the support plate 21 is 5 mm, the length L2Y in the Y direction of the support plate 21 included in both the region R1 and the region R2 is about 177 mm, and the length L2X in the X direction is about 632 mm. If the thickness L2Za of the support plate 21 is 5 mm at most, it is possible to configure the step plate and the support plate 21 so that the deflection of the step plate is 6 mm or less. Since the length L2X in the X direction of the support plate 21 included in both the region R1 and the region R2 varies depending on the length L1X in the X direction of the step plate 10, the preferable range of the length L2X can be determined by the ratio with the length L1X. From the above, it is clear that the length L2X of the support plate 21 that is difficult to see is 0.84 times or less than the length L1X. In this specification and the claims, the above 0.84 times is a value rounded off to two decimal places.

[0026] Similarly, the area S2 of the underside of the support plate 21 that is difficult to see can also be defined as the area S2 of the underside of the support plate 21 relative to the area S1 of the underside of the footboard 10 in Fig. 3. This is because the area S1 can be calculated from the lengths L1X and L1Y, and the area S2 can be calculated from the lengths L2X and L2Y. From the above, it is preferable that the area S2 of the underside of the support plate 21 that is difficult to see is 0.71 times or less the area S1. In this specification and claims, the above 0.71 times is a value rounded off to two decimal places.

[0027] When the lower support tool 20 has a rib 22, the rib 22 is preferably disposed so as to be included in both the region R1 and the region R2. That is, it is preferable that the sum of the maximum length L2Zb of the rib 22 in the Z direction and the thickness L2Za of the support plate 21 is 32 mm or less. Even if the above cannot be satisfied, by making the rib 22 have a tapered shape as described above, the rib 22 has a shape similar to the region R2, so that it is easy to dispose the rib 22 in the region R2. Therefore, the rib 22 can be disposed so as to be difficult to see.

[0028] (Fixing member) The fixing member 31 is disposed vertically above one end side (the column 40 side) of the step plate 10 as shown in Figs. 1 and 2. Similarly, the fixing member 32 is disposed vertically below one end side (the column 40 side) of the step plate 10 as shown in Figs. 1 and 2. The fixing members 31 and 32 clamp and fix the step plate 10 and the end of one end side of the lower support 20. In this embodiment, the fixing members 31 and 32 clamp and fix the support plate 21 together with the step plate 10 as shown in Fig. 5. With the above configuration, the support plate 21 is mechanically fixed to the fixing members 31 and 32. Therefore, for example, even if the joint between the support plate 21 and the step plate 10 is peeled off, the support plate 21 can be prevented from falling off. Furthermore, a higher strength can be obtained compared to the case where the support plate 21 and the fixing members 31 and 32 are fixed by welding or the like. In this embodiment, the fixing members will be described below as a pair of fixing members 31 and 32. On the other hand, the fixing member according to the present disclosure need only be capable of clamping the footboard 10 and one end of the lower support 20, and is not limited to a pair of fixing members.

[0029] The material constituting the fixing members 31 and 32 is not particularly limited, but is preferably a metallic material. Examples of metallic materials include steel.

[0030] The fixing members 31 and 32 are fastened to each other at both ends in the Y direction while sandwiching the footboard 10 and the support plate 21. In this embodiment, the fixing members 31 and 32 have fixing holes h1 formed in both ends in the Y direction, as shown in Figures 3 and 4.

[0031] As shown in Fig. 5, the fixing members 31 and 32 are plate-like members having a generally T-shaped configuration with both ends in the Y direction narrowed. By narrowing both ends in the Y direction of the fixing members 31 and 32, the depth L3Z of the hole h1 formed at both ends can be reduced. This makes it easier to adjust the thicknesses L3Y and L5X around the hole h1, which will be described later.

[0032] In this embodiment, the fixing member 31 and the fixing member 32 have substantially the same shape and are arranged symmetrically in the vertical direction. However, the fixing member 32 has a recess r1 formed according to the cross-sectional shape of the support plate 21. The end of one end of the support plate 21 is arranged in the recess r1 of the fixing member 32, and the end of one end of the footboard 10 is arranged further above. In this embodiment, the recess r1 penetrates the fixing member 32 in the X direction. On the other hand, the recess r1 does not have to penetrate in the X direction. For example, the recess r1 may be a recess that opens at the tip side of the footboard 10 and does not penetrate to the column 40 side. The fixing member 31 is arranged above the footboard 10. The holes h1 of the fixing members 31 and 32 and the holes formed on one end side of the footboard 10 are arranged to communicate with each other. By inserting and fastening the fixing tool f1 into the above-mentioned communicating hole, the fixing members 31 and 32 clamp and fix the end of the footboard 10 and the end of one end of the lower support tool 20. The fastener f1 may be, for example, a bolt and a nut.

[0033] The thickness (length in the X direction) L4X of the fixing members 31 and 32 is preferably set to be equal to or greater than the hole diameter of the hole portion h1 plus twice the nominal diameter of the fixing device f1. This ensures sufficient strength of the fixing members 31 and 32. The axial force of the fixing device f1 is preferably equal to or greater than 12,500 N in total. This ensures safety when a person stands on the footboard 10 even if the joint between the support plate 21 and the footboard 10 is peeled off. The axial force of the fixing device f1 depends on the nominal diameter and torque of the fixing device f1. From the above viewpoint, the nominal diameter of the fixing device f1 is preferably equal to or greater than 8 mm. This allows the axial force of each fixing device f1 to be equal to or greater than 6,250 N. The torque varies depending on the nominal diameter, but for example, when the nominal diameter is 8 mm, it can be set to 12.5 N·m, and when the nominal diameter is 10 mm, it can be set to 24.5 N·m.

[0034] It is preferable that the length L4X is equal to or less than the length L3X, which is the length from one end of the tread 10 to the location where the interior wall is disposed. This allows the fixing members 31 and 32 to be disposed in positions that cannot be seen from the outside, improving the design of the cantilever staircase support structure 100. From the above viewpoint, it is preferable that L4X is equal to or greater than 20 mm and equal to or less than 45 mm.

[0035] The depth L3Z of the hole h1 shown in Fig. 5 (equal to the length in the Z direction at both ends in the Y direction of the fixing members 31 and 32) is preferably shorter than L3Y and L5X, which are the thicknesses around the hole h1 shown in Fig. 4. With the above-mentioned configuration, buckling and uneven thickness of the fixing members 31 and 32 can be suppressed.

[0036] The front surface of the fixing member 32 is formed with a fixing hole h2 penetrating in the X direction. The hole h2 is arranged so as to communicate with a hole formed in an end portion of the rib 22 on one end side in the X direction (the column 40 side). In this state, a fastener f2 is inserted into the hole h2 and fastened, whereby the one end side of the rib 22 in the X direction is fixed by the fixing member 32. With the above configuration, even if the joint between the rib 22 and the support plate 21 is peeled off, the rib 22 can be prevented from falling off. Furthermore, the above configuration can be easily processed by simply forming the hole h2 in the fixing member 32.

[0037] For example, a fixing hole h4 penetrating in the X direction is formed on the front surface of the fixing members 31 and 32. The fixing members 31 and 32 can be fixed by inserting a fastener into the hole h4 and fastening it to the pillar 40.

[0038] Second Embodiment Other embodiments of the present disclosure will be described below. Configurations similar to those in the first embodiment will be denoted by the same reference numerals and descriptions thereof may be omitted.

[0039] As shown in FIG. 6, the support structure 110 for the cantilever staircase according to the second embodiment includes a fixing member 31 and a fixing member 32a.

[0040] The fixing member 31 has the same configuration as the first embodiment, and is disposed vertically above one end side (the column 40 side) of the step plate 10. As shown in FIG. 6, the fixing member 32a is disposed vertically below one end side (the column 40 side) of the step plate 10. The fixing members 31 and 32a clamp and fix the end of the step plate 10 and one end side of the lower support 20. In this embodiment, as shown in FIG. 6, the fixing members 31 and 32a clamp and fix the support plate 21 and the rib 22 together with the step plate 10. With the above configuration, the support plate 21 and the rib 22 are mechanically fixed to the fixing members 31 and 32. Therefore, for example, even if the joint between the support plate 21 and the step plate 10 or the joint between the rib 22 and the support plate 21 is peeled off, the support plate 21 and the rib 22 can be prevented from falling off.

[0041] The fixing member 32a is formed with a recess r2 corresponding to the cross-sectional shape of the support plate 21 and the rib 22. The end portions of the support plate 21 and the rib 22 on one end side are arranged in the recess r2 of the fixing member 32a, and the end portion of the footboard 10 on one end side is arranged further above. In this embodiment, the recess r2 penetrates the fixing member 32a in the X direction. On the other hand, the recess r2 does not have to penetrate in the X direction. For example, the recess r2 may be a recess that opens at the tip side of the footboard 10 and does not penetrate to the column 40 side. The fixing member 31 is arranged above the footboard 10. The holes h1 of the fixing member 31 and the fixing member 32a and the holes formed on one end side of the footboard 10 are arranged so as to communicate with each other. By inserting and fastening the fastener f1 into the above-mentioned communicating hole portion, the footboard 10, as well as the ends of the support plate 21 and the rib 22 on one end side are clamped and fixed by the fixing member 31 and the fixing member 32a.

[0042] A hole h3 is formed in the lower surface of the fixing member 32a, penetrating the recess r2 in the Y direction. In this embodiment, a hole is formed in one end of the rib 22 in the X direction (on the column 40 side) that extends vertically upward from the vertical lower end in the Y direction. The hole is arranged to communicate with the hole h3. By inserting a fastener f3 into the hole h3 and fastening it, the rib 22 and the fixing member 32a can be fixed more firmly.

[0043] The support structure for stairs according to the embodiment of the present disclosure has been described above. However, the present disclosure is not limited to the above embodiment and can be modified as appropriate. [Explanation of symbols]

[0044] 100, 110 Staircase support structure, 10, 10a, 10b, 10c Tread, 20 Lower support, 21 Support plate, 22 Rib, 31, 32, 32a Fixing member

Claims

1. A support structure for a cantilever staircase comprising a step and a lower support that supports the step from below, A support structure for a cantilever staircase, comprising fixing members respectively arranged vertically above and below one end side of the step and the lower support, and clamping and fixing the step and the lower support.

2. The support structure for a cantilever staircase as described in claim 1, wherein the lower support device comprises a plate-shaped support plate that abuts against the lower surface of the tread and a rib that protrudes downward from the support plate.

3. The support structure for a cantilever staircase according to claim 2 , wherein the fixing member clamps and fixes at least the support plate together with the tread.

4. The support structure for a cantilever staircase according to claim 2 , wherein the fixing member clamps and fixes the support plate and the rib together with the tread.

5. The support structure for a cantilever staircase according to claim 2 , wherein the rib is fixed to the fixing member by inserting a fixing device from the main body side.

6. The support structure for a cantilever staircase as described in claim 2, wherein the rib is arranged in a recess provided in the fixing member and is fixed to the fixing member by inserting a fixing device into the fixing member from below.

7. 3. The support structure for a cantilever staircase according to claim 1 or 2, wherein the tread is made of fiber reinforced plastic.

8. 3. The support structure for a cantilever staircase according to claim 1 or 2, wherein the tread is made of carbon fiber reinforced plastic.

9. The support structure for a cantilever staircase according to claim 8, wherein the thickness of the tread is 30 mm or less.

10. The lower support extends from one end side of the footboard to the other end side, 3. A support structure for a cantilever staircase as described in claim 1 or 2, wherein the longitudinal length of the lower support is 0.84 times or less the longitudinal length of the tread.

11. The support structure for a cantilever staircase as described in claim 10, wherein the area of ​​the lower surface of the lower support is 0.71 times or less the area of ​​the lower surface of the tread.

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