JP7014547B2

JP7014547B2 - Exposed stairs structure

Info

Publication number: JP7014547B2
Application number: JP2017160371A
Authority: JP
Inventors: 康司菅原; 湖持田
Original assignee: Wood One Co Ltd
Current assignee: Wood One Co Ltd
Priority date: 2017-06-23
Filing date: 2017-08-23
Publication date: 2022-02-01
Anticipated expiration: 2037-08-23
Also published as: JP2019007323A

Description

本発明は、露出階段である直線階段の下部に、露出階段である廻り階段が接続される露出階段構造に関するものである。 The present invention relates to an exposed staircase structure in which a circular staircase, which is an exposed staircase, is connected to the lower part of a straight staircase, which is an exposed staircase.

露出階段は、高級感があって、軽快な印象を受けるので、玄関ホール等の演出の為に用いられる場合が多い。大半が直線階段としての施工であり、廻り階段部分までも露出とする例は僅かしかなかった。 Exposed stairs have a high-class feel and give a light impression, so they are often used for the production of entrance halls and the like. Most of the work was done as straight stairs, and there were only a few cases where even the surrounding stairs were exposed.

以下に、露出階段である直線階段に廻り階段を組み合わせた代表的な構造例を示す（特許文献１乃至３参照）。
特許文献１又は２に記載の発明では、露出階段のササラ桁上部を通常の固定方法で上階に固定する。一方、廻り階段部分をブロック状の箱型階段とした上で、柱と腰板に渡した力桁受木にササラ桁下部を固定するかあるいは、床に直接ササラ桁下部を固定している。要するに露出階段は直線部分のみで、廻り階段部分は箱型階段となる。廻り階段部分裏面側は表面から隠蔽されているので補強材等を設けることも容易で、強度面でも有利となる。 The following is a typical structural example in which a straight staircase, which is an exposed staircase, is combined with a circular staircase (see Patent Documents 1 to 3).
In the invention described in Patent Document 1 or 2, the upper part of the Sasara girder of the exposed staircase is fixed to the upper floor by a usual fixing method. On the other hand, after the surrounding stairs are made into block-shaped box-shaped stairs, the lower part of the Sasara girder is fixed to the force girder receiving tree passed to the pillar and the wainscot, or the lower part of the Sasara girder is fixed directly to the floor. In short, the exposed stairs are only straight parts, and the surrounding stairs are box-shaped stairs. Since the back surface side of the surrounding staircase portion is concealed from the front surface, it is easy to provide a reinforcing material or the like, which is advantageous in terms of strength.

特許文献３に記載の発明は、露出階段のササラ桁は通常の露出階段のように施工した上で、廻り階段部分は廻り階段とする部分のみ補助支柱を複数設置して廻り踏板を設置する。ササラ桁にて支持できない部分は補助支柱が支持する。強度面では直線の露出階段同等で問題無いが、廻り踏板裏面には、ササラ桁や補助支柱等が林立状態となってしまうので、隙間は僅かしか無い。
また、直線ササラ桁の下部を廻り階段とは別に支柱で支持しているものもある。 In the invention described in Patent Document 3, the sasara girder of the exposed staircase is constructed like a normal exposed staircase, and a plurality of auxiliary columns are installed only in the portion of the rotating staircase to be the rotating staircase, and the rotating tread is installed. Auxiliary columns support the parts that cannot be supported by the Sasara girder. In terms of strength, there is no problem with a straight exposed staircase, but there is only a small gap on the back of the stair tread because the sasara girders and auxiliary columns are in a forested state.
In addition, there are some that go around the lower part of the straight Sasara girder and support it with columns separately from the stairs.

実公昭６２－００７７８２号公報Jikken Akira 62-007782 Gazette 特開２００９－２３５６８８号公報Japanese Unexamined Patent Publication No. 2009-235688 特許第５６２５１６１号公報Japanese Patent No. 5625161

しかしながら、従来の階段の場合、以下のような問題点があった。
特許文献１又は２のように、直線階段は露出階段にもかかわらず廻り階段部分のみ箱型階段の構造とした場合、一つの階段の途中で階段の雰囲気が変わってしまうので違和感がある。 However, in the case of the conventional stairs, there are the following problems.
As in Patent Document 1 or 2, if the straight staircase has a box-shaped staircase structure only in the surrounding staircase despite being an exposed staircase, the atmosphere of the staircase changes in the middle of one staircase, which makes it uncomfortable.

特許文献３のように、階下の廻り階段２～３段分のみ別途支持柱を設けて支持する場合、この部分はササラ桁、支柱等が林立し、廻り階段の内部が混沌とした状態となってしまうので、露出階段が本来持つ軽快感を喪失してしまう。
また、掃除を行う際には、支柱等が林立しているので掃除機のノズルが入り難く、特に埃が溜まり易い床面付近の掃除が困難である。 As in Patent Document 3, when a support pillar is separately provided and supported only for the 2 to 3 steps of the round stairs downstairs, Sasara girders, pillars, etc. stand in this part, and the inside of the round stairs becomes chaotic. Therefore, the lightness that the exposed stairs originally have is lost.
In addition, when cleaning, it is difficult for the nozzle of the vacuum cleaner to enter because the columns and the like are standing in a forest, and it is particularly difficult to clean the vicinity of the floor surface where dust easily collects.

また、直線ササラ桁の下部を廻り階段とは別に支柱で支持する場合には、直線階段の重量を支え、かつ、前にずれようとする力に対抗できる様に、太く大きな部材あるいは金属などの強い部材を使う必要がある。 In addition, when the lower part of the straight Sasara girder is supported by a support column separate from the stairs, a thick and large member or metal is used to support the weight of the straight stairs and to counter the force of shifting forward. It is necessary to use strong materials.

そこで、本発明の目的とするところは、構造が単純で廻り階段も露出階段で違和感が無い露出階段構造を提供することにある。 Therefore, an object of the present invention is to provide an exposed staircase structure having a simple structure and having an exposed staircase that does not give a sense of discomfort.

上記の目的を達成するために、本発明の請求項１に記載の露出階段構造は、露出階段である直線階段（１００）の下部に三段廻り階段（２００）が接続される階段構造であって、前記三段廻り階段（２００）は、第一廻り踏板（３１）、前記第一廻り踏板（３１）の一段下段の第二廻り踏板（３２）及び前記第二廻り踏板（３２）の一段下段の第三廻り踏板（３３）を支持する廻りササラ桁（４０）を有し、前記廻りササラ桁（４０）は、前記直線階段（１００）と同じ方向に延びるように前記三段廻り階段（２００）における外周側に配置され、前記第一廻り踏板（３１）、前記第二廻り踏板（３２）及び前記直線階段（１００）の一方の直線ササラ桁（１）を支持する第一桁部材（４１）と、前記直線階段（１００）と垂直方向に延びるように前記三段廻り階段（２００）における外周側に配置され、前記第二廻り踏板（３２）及び前記第三廻り踏板（３３）を支持する第二桁部材（４２）と、前記三段廻り階段（２００）における内周側に配置され、前記第一廻り踏板（３１）、前記第二廻り踏板（３２）、前記第三廻り踏板（３３）及び前記直線階段（１００）の他方の直線ササラ桁（１）を支持する平面視略Ｌ字状の第三桁部材（４３）と、を備え、前記直線階段（１００）の直線ササラ桁（１）の上部の接続端部（１ａ）と、梁等の階上構造部材（２）と、が接続部材（１０，２０）を介して接続され、さらに前記第一桁部材（４１）、前記第二桁部材（４２）及び前記第三桁部材（４３）は全て木製で、しかも前記三段廻り階段（２００）は蹴込み板と他の支柱及び力桁受木を有さないことを特徴とする。 In order to achieve the above object, the exposed stair structure according to claim 1 of the present invention is a stair structure in which a three-step round stair (200) is connected to the lower part of a straight stair (100) which is an exposed stair. The three-step round staircase (200) is one step of the first round tread (31), the second round tread (32) one step lower of the first round tread (31), and the second round tread (32). It has a rotating sasara girder (40) that supports the lower third round tread (33), and the rotating sasara girder (40) extends in the same direction as the straight stairs (100). A first girder member (1) arranged on the outer peripheral side of the 200) and supporting one of the straight sasara girders (1) of the first stair tread (31), the second stair tread (32) and the straight stairs (100). 41) and the second round tread (32) and the third round tread (33) are arranged on the outer peripheral side of the three-step round stair (200) so as to extend in the direction perpendicular to the straight stair (100). The second girder member (42) to be supported and the first round tread (31), the second round tread (32), and the third round tread arranged on the inner peripheral side of the three-step round staircase (200). (33) and a third girder member (43) having a substantially L-shape in plan view supporting the other straight sasara girder (1) of the straight stairs (100), and the straight sasara of the straight stairs (100). The connecting end portion (1a) on the upper part of the girder (1) and the floor structural member (2) such as a beam are connected via the connecting member (10, 20), and further, the first girder member (41). The second girder member (42) and the third girder member (43) are all made of wood, and the three-step round staircase (200) does not have a riser plate, other columns, and a force girder receiver. It is characterized by.

また、請求項２に記載の露出階段構造は、前記直線ササラ桁（１）の接続端部（１ａ）に、上方及び前方に開口する取付溝（１ｂ）が形成されるとともに、前記接続部材（１０，２０）は、凸状又は凹状の第一嵌合部（１５）を有し、前記取付溝（１ｂ）から突出しないように前記取付溝（１ｂ）に装着される第一接続金具（１０）と、前記第一接続金具（１０）の第一嵌合部（１５）と嵌合する凹状又は凸状の第二嵌合部（２２）を有し、前記階上構造部材（２）に取付けられる第二接続金具（２０）と、を備えることを特徴とする。 Further, in the exposed staircase structure according to claim 2 , a mounting groove (1b) that opens upward and forward is formed at the connection end portion (1a) of the straight line sasara girder (1), and the connection member (1b). The first connecting fitting (10) has a convex or concave first fitting portion (15) and is mounted in the mounting groove (1b) so as not to protrude from the mounting groove (1b). ), And a concave or convex second fitting portion (22) that fits with the first fitting portion (15) of the first connection fitting (10), and the floor structure member (2) has a concave or convex second fitting portion (22). It is characterized by comprising a second connection fitting (20) to be attached.

また、請求項３に記載の露出階段構造は、前記第一桁部材（４１）と前記第二桁部材（４２）の互いに接する側の端部を互いに上下に重ねて接合することを特徴とする。 Further, the exposed staircase structure according to claim 3 is characterized in that the ends of the first girder member (41) and the second girder member (42) on the side in contact with each other are overlapped and joined to each other. ..

また、請求項４に記載の露出階段構造は、直線階段（１００）の下部に廻り階段（２００）が接続される露出階段構造であって、前記廻り階段（２００）は、廻り踏板（３１，３２，３３）及び廻り踏板（３１，３２，３３）を支持する廻りササラ桁（４０）を有し、
前記廻りササラ桁（４０）は、前記直線階段（１００）と同じ方向に延びるように前記廻り階段（２００）における外周側に配置される第一桁部材（４１）と、前記直線階段（１００）と異なる方向に延びるように前記廻り階段（２００）における外周側に配置される第二桁部材（４２）と、前記廻り階段（２００）における内周側に配置される第三桁部材（４３）と、を備え、前記直線階段（１００）の左右それぞれの直線ササラ桁（１）の上部の接続端部（１ａ）と、階上構造部材（２）と、が接続部材（１０）を介して接続されるとともに、一方の前記直線ササラ桁（１）の下部の接続端部（１ｄ）が前記第一桁部材（４１）の上部に接続されるとともに、他方の前記直線ササラ桁（１）の下部の接続端部（１ｄ）が前記第三桁部材（４３）の上部に接続され、しかも前記第一桁部材（４１）と前記第三桁部材（４３）における、前記直線ササラ桁（１）の下部の接続端部（１ｄ）が接続された部位の下部が設置面に支持されることを特徴とする。 Further, the exposed staircase structure according to claim 4 is an exposed staircase structure in which a rotating staircase (200) is connected to a lower portion of a straight staircase (100), and the rotating staircase (200) is a rotating tread plate (31, It has a rotating sasara girder (40) that supports 32,33) and a rotating tread (31,32,33).
The peripheral sasara girder (40) has a first girder member (41) arranged on the outer peripheral side of the circular staircase (200) so as to extend in the same direction as the straight staircase (100), and the linear staircase (100). The second girder member (42) arranged on the outer peripheral side of the circular staircase (200) so as to extend in a different direction from the above, and the third girder member (43) arranged on the inner peripheral side of the circular staircase (200). And, the connection end portion (1a) at the upper part of the straight line Sasara girder (1) on each of the left and right sides of the straight staircase (100), and the upstairs structural member (2) are connected via the connection member (10). At the same time as being connected, the connecting end portion (1d) at the lower part of the straight line Sasara girder (1) is connected to the upper part of the first girder member (41), and the other straight line Sasara girder (1). The lower connecting end (1d) is connected to the upper part of the third girder member (43), and the straight line sasara girder (1) in the first girder member (41) and the third girder member (43). It is characterized in that the lower part of the portion to which the connecting end portion (1d) of the lower part is connected is supported by the installation surface.

また、請求項５に記載の露出階段構造は、直線階段（１００）の下部に廻り階段（２００）が接続される露出階段構造であって、前記廻り階段（２００）は、廻り踏板（３１，３２，３３）及び廻り踏板（３１，３２，３３）を支持する廻りササラ桁（４０）を有し、
前記廻りササラ桁（４０）は、前記直線階段（１００）と同じ方向に延びるように前記廻り階段（２００）における外周側に配置される第一桁部材（４１）と、前記直線階段（１００）と異なる方向に延びるように前記廻り階段（２００）における外周側に配置される第二桁部材（４２）と、前記廻り階段（２００）における内周側に配置される第三桁部材（４３）と、を備え、前記直線階段（１００）の左右それぞれの直線ササラ桁（１）の上部の接続端部（１ａ）と、階上構造部材（２）と、が接続部材（１０）を介して接続されるとともに、一方の前記直線ササラ桁（１）の下部の接続端部（１ｄ）が前記第一桁部材（４１）の上部に接続されるとともに、他方の前記直線ササラ桁（１）の下部の接続端部（１ｄ）が前記第三桁部材（４３）の上部に接続され、しかも前記第一桁部材（４１）と前記第三桁部材（４３）における、前記直線ササラ桁（１）の下部の接続端部（１ｄ）が接続された部位の下部が設置面に支持され、前記第一桁部材（４１）は複数の木質部材からなり、前記直線ササラ桁（１）の下部の接続端部（１ｄ）が接続される部材には略鉛直方向の繊維方向となる木質部材（４１ｄ）、他の部材には階段の傾斜方向の繊維方向となる木質部材（４１ｅ）、を含むことを特徴とする。 Further, the exposed staircase structure according to claim 5 is an exposed staircase structure in which a rotating staircase (200) is connected to a lower portion of a straight staircase (100), and the rotating staircase (200) is a rotating tread plate (31, It has a rotating sasara girder (40) that supports 32,33) and a rotating tread (31,32,33).
The peripheral sasara girder (40) has a first girder member (41) arranged on the outer peripheral side of the circular staircase (200) so as to extend in the same direction as the straight staircase (100), and the linear staircase (100). The second girder member (42) arranged on the outer peripheral side of the circular staircase (200) so as to extend in a different direction from the above, and the third girder member (43) arranged on the inner peripheral side of the circular staircase (200). And, the connection end portion (1a) at the upper part of the straight line Sasara girder (1) on each of the left and right sides of the straight staircase (100), and the upstairs structural member (2) are connected via the connection member (10). At the same time as being connected, the connecting end portion (1d) at the lower part of the straight line Sasara girder (1) is connected to the upper part of the first girder member (41), and the other straight line Sasara girder (1). The lower connecting end (1d) is connected to the upper part of the third girder member (43), and the straight line sasara girder (1) in the first girder member (41) and the third girder member (43). The lower part of the portion to which the connecting end portion (1d) of the lower part is connected is supported by the installation surface, the first girder member (41) is composed of a plurality of woody members, and the lower part of the straight line Sasara girder (1) is connected. The member to which the end portion (1d) is connected includes a wood member (41d) in the fiber direction in the substantially vertical direction, and the other members include a wood member (41e) in the fiber direction in the inclined direction of the stairs. It is a feature.

また、請求項６に記載の露出階段構造は、直線階段（１００）の下部に廻り階段（２００）が接続される露出階段構造であって、前記廻り階段（２００）は、廻り踏板（３１，３２，３３）及び廻り踏板（３１，３２，３３）を支持する廻りササラ桁（４０）を有し、
前記廻りササラ桁（４０）は、前記直線階段（１００）と異なる方向に延びるように前記廻り階段（２００）における外周側に配置される第二桁部材（４２）と、前記廻り階段（２００）における内周側に配置される第三桁部材（４３）と、を備え、前記直線階段（１００）の直線ササラ桁（１）の上部の接続端部（１ａ）と、階上構造部材（２）と、が接続部材（１０）を介して接続されるとともに、前記直線ササラ桁（１）の下部の接続端部（１ｄ）が前記第三桁部材（４３）に接続され、しかも前記第三桁部材（４３）における、前記直線ササラ桁（１）の下部の接続端部（１ｄ）が接続された部位の下部が接地面に支持されることを特徴とする。 Further, the exposed staircase structure according to claim 6 is an exposed staircase structure in which a rotating staircase (200) is connected to a lower portion of a straight staircase (100), and the rotating staircase (200) is a rotating tread plate (31, It has a rotating sasara girder (40) that supports 32,33) and a rotating tread (31,32,33).
The peripheral sasara girder (40) has a second girder member (42) arranged on the outer peripheral side of the circular staircase (200) so as to extend in a direction different from that of the straight staircase (100), and the circular staircase (200). A third girder member (43) arranged on the inner peripheral side of the staircase, the connection end portion (1a) at the upper part of the straight line sasara girder (1) of the straight staircase (100), and the floor structure member (2). ) Is connected via the connecting member (10), and the connecting end portion (1d) at the lower part of the straight line Sasara girder (1) is connected to the third girder member (43). The girder member (43) is characterized in that the lower portion of the portion to which the connecting end portion (1d) of the lower portion of the straight line sasara girder (1) is connected is supported by the ground contact surface.

ここで、上記括弧内の記号は、図面および後述する発明を実施するための形態に掲載された対応要素または対応事項を示す。 Here, the symbols in parentheses indicate the corresponding elements or corresponding items described in the drawings and the embodiment for carrying out the invention described later.

本発明によれば、三段廻り階段も蹴込み板を有さない露出階段で、しかも第一桁部材、第二桁部材及び第三桁部材は全て木製なので、その上部に接続される露出階段である直線階段と連続性があり、違和感が無い。
また、本発明によれば、三段廻り階段は蹴込み板と他の支柱及び力桁受木を有さないので、構造が単純である。よって、三段廻り階段であっても直線階段の露出階段が持つ軽快感を有し、しかも内部の掃除が楽である。 According to the present invention, the three-step round staircase is also an exposed staircase without a riser plate, and since the first girder member, the second girder member and the third girder member are all made of wood, the exposed staircase connected to the upper part thereof. There is continuity with the straight stairs, and there is no sense of discomfort.
Further, according to the present invention, the three-step round staircase does not have a riser plate, other columns, and a force girder receiver, so that the structure is simple. Therefore, even if it is a three-step staircase, it has the light feeling of an exposed staircase of a straight staircase, and it is easy to clean the inside.

また、本発明によれば、直線階段の直線ササラ桁の上部の接続端部と、梁等の階上構造部材と、が接続部材を介して接続され、接続部材は、直線ササラ桁の荷重によって三段廻り階段が水平移動してしまわないだけの接続強度を有するので、三段廻り階段に求められる強度が低い。 Further, according to the present invention, the connecting end of the upper part of the straight sasara girder of the straight staircase and the floor structural member such as a beam are connected via the connecting member, and the connecting member is connected by the load of the straight sasara girder. Since the connection strength is such that the three-step stairs do not move horizontally, the strength required for the three-step stairs is low.

また、本発明によれば、特に接続部材は、凸状又は凹状の第一嵌合部を有し、取付溝から突出しないように取付溝に装着される第一接続金具と、第一接続金具の第一嵌合部と嵌合する凹状又は凸状の第二嵌合部を有し、階上構造部材に取付けられる第二接続金具と、を備えるので、直線ササラ桁の荷重によって三段廻り階段が水平移動してしまわないだけの接続強度となる。 Further, according to the present invention, in particular, the connection member has a first fitting portion having a convex or concave shape, and a first connection fitting and a first connection fitting which are mounted in the mounting groove so as not to protrude from the mounting groove. It has a concave or convex second fitting part that fits with the first fitting part of the above, and is equipped with a second connection fitting that can be attached to the upstairs structural member. The connection strength is such that the stairs do not move horizontally.

また、本発明によれば、第一桁部材と第二桁部材の互いに接する側の端部を互いに上下に重ねて接合するので、三段廻り階段の強度を向上することができる。 Further, according to the present invention, since the ends of the first girder member and the second girder member on the side where they are in contact with each other are vertically overlapped and joined to each other, the strength of the three-step round staircase can be improved.

また、直線ササラ桁の下部の接続端部が接続された第一桁部材と第三桁部材における部位の下部が接地面に支持されるので、直線ササラ桁を第一桁部材や第三桁部材でそれぞれ支持可能である。
特に、第一桁部材は複数の木質部材からなり、直線ササラ桁が接続される部材の繊維方向は略鉛直方向で、他の部材の少なくとも一つの繊維方向は階段の傾斜方向となるようにすると、強度を確保可能である。 Further, since the lower part of the portion of the first girder member and the third girder member to which the connecting end of the lower part of the straight sasara girder is connected is supported by the ground plane, the straight sasara girder can be used as the first girder member or the third girder member. Can be supported by.
In particular, the first girder member is composed of a plurality of woody members, and the fiber direction of the member to which the straight Sasara girder is connected is substantially vertical, and the fiber direction of at least one of the other members is the inclination direction of the stairs. , Strength can be secured.

本発明の第一実施形態に係る露出階段構造における三段廻り階段の第一桁部材を示す図であり、（ａ）は平面図、（ｂ）は側面図である。It is a figure which shows the 1st girder member of the 3 step round stairs in the exposed stairs structure which concerns on 1st Embodiment of this invention, (a) is a plan view, (b) is a side view. 本発明の第一実施形態に係る露出階段構造における三段廻り階段の第二桁部材を示す図であり、（ａ）は平面図、（ｂ）は正面図である。It is a figure which shows the 2nd girder member of the 3 step round stairs in the exposed stairs structure which concerns on 1st Embodiment of this invention, (a) is a plan view, (b) is a front view. 本発明の第一実施形態に係る露出階段構造における三段廻り階段の第三桁部材を示す図であり、（ａ）は平面図、（ｂ）は正面図、（ｃ）は側面図である。It is a figure which shows the 3rd girder member of the 3 step round stairs in the exposed stairs structure which concerns on 1st Embodiment of this invention, (a) is a plan view, (b) is a front view, (c) is a side view. .. 本発明の第一実施形態に係る露出階段構造における三段廻り階段を示す斜視図である。It is a perspective view which shows the three steps around the stairs in the exposed step structure which concerns on 1st Embodiment of this invention. 本発明の第一実施形態に係る露出階段構造における三段廻り階段を示す斜視図である。It is a perspective view which shows the three steps around the stairs in the exposed step structure which concerns on 1st Embodiment of this invention. 本発明の第一実施形態に係る露出階段構造における三段廻り階段を示す斜視図である。It is a perspective view which shows the three steps around the stairs in the exposed step structure which concerns on 1st Embodiment of this invention. 本発明の第一実施形態に係る露出階段構造における第一接続金具を示す斜視図である。It is a perspective view which shows the 1st connection metal fitting in the exposed staircase structure which concerns on 1st Embodiment of this invention. 本発明の第一実施形態に係る露出階段構造における第二接続金具を示す斜視図である。It is a perspective view which shows the 2nd connection metal fitting in the exposed staircase structure which concerns on 1st Embodiment of this invention. 本発明の第一実施形態に係る露出階段構造における第一接続金具と第二接続金具との嵌合時の状態を示す側面図である。It is a side view which shows the state at the time of fitting of the 1st connection metal fitting and the 2nd connection metal fitting in the exposed staircase structure which concerns on 1st Embodiment of this invention. 本発明の第二実施形態に係る露出階段構造における三段廻り階段の第一桁部材、第二桁部材、及び第三桁部材を示す平面図および側面図である。It is a top view and the side view which shows the 1st girder member, the 2nd girder member, and the 3rd girder member of the three-step round staircase in the exposed staircase structure which concerns on the 2nd Embodiment of this invention. 本発明の第二実施形態に係る露出階段構造における三段廻り階段を示す斜視図である。It is a perspective view which shows the three steps around the stairs in the exposed step structure which concerns on the 2nd Embodiment of this invention. 本発明の直線ササラ桁と廻りササラ桁の設置を示す図である。It is a figure which shows the installation of the straight Sasara girder and the circular Sasara girder of this invention. 本発明の他の実施形態に係る露出階段構造における三段廻り階段の第三桁部材を示す図であり、（ａ）は平面図、（ｂ）は正面図、（ｃ）は側面図である。It is a figure which shows the 3rd girder member of the 3 step round stairs in the exposed stairs structure which concerns on other embodiment of this invention, (a) is a plan view, (b) is a front view, (c) is a side view. ..

(第一実施形態)
図１乃至図９を参照して、本発明の第一実施形態に係る露出階段構造を説明する。
この露出階段構造は、露出階段である直線階段１００の下部に三段廻り階段２００が接続される。そして、直線階段１００だけでなく三段廻り階段２００も蹴込み板を有さない露出階段であることを特徴とする（例えば図５参照）。
本実施形態においては、直線階段１００から見て梁等の階上構造部材２の方向を前方とし、また直線階段１００の直線ササラ桁１の厚さ方向を左右方向とした。つまり、直線階段から階上構造部材２の方向を向いたときの右を、本実施形態における右としている。
なお、図１については紙面左方が本実施形態における前方、図２については紙面左方が本実施形態における左方、図３（ｃ）については紙面左方が本実施形態における後方である。 (First embodiment)
The exposed staircase structure according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 9.
In this exposed staircase structure, a three-step round staircase 200 is connected to the lower part of a straight staircase 100 which is an exposed staircase. Not only the straight staircase 100 but also the three-step round staircase 200 is an exposed staircase having no riser plate (see, for example, FIG. 5).
In the present embodiment, the direction of the upper-floor structural member 2 such as a beam is set to the front when viewed from the straight stairs 100, and the thickness direction of the straight Sasara girder 1 of the straight stairs 100 is set to the left-right direction. That is, the right side when facing the direction of the upstairs structural member 2 from the straight staircase is the right side in the present embodiment.
In FIG. 1, the left side of the paper is the front in the present embodiment, in FIG. 2, the left side of the paper is the left in the present embodiment, and in FIG. 3C, the left side of the paper is the rear in the present embodiment.

まず、三段廻り階段２００について説明する。
三段廻り階段２００は、第一廻り踏板３１、第二廻り踏板３２、第三廻り踏板３３の三枚の廻り踏板３０と、廻り踏板３０を支持する外周側及び内周側の廻りササラ桁４０を有するとともに、他の支柱及び力桁受木を有さない。
また、三段廻り階段２００は露出階段であるので、蹴込み板を有さない。 First, the three-step round staircase 200 will be described.
The three-step round staircase 200 includes three round treads 30, a first round tread 31, a second round tread 32, and a third round tread 33, and a round fillet girder 40 on the outer peripheral side and the inner peripheral side that supports the round tread 30. And does not have other stanchions and stair treads .
Further, since the three-step round staircase 200 is an exposed staircase, it does not have a riser plate.

廻り踏板３０は、上から順番に第一廻り踏板３１、第二廻り踏板３２、第三廻り踏板３３となっている。つまり、第一廻り踏板３１の一段下段が第二廻り踏板３２、第二廻り踏板３２の一段下段が第三廻り踏板３３である。
本実施形態における廻り踏板３０は従来の廻り踏板と同様の形状である。つまり、第一廻り踏板３１と第三廻り踏板３３は平面視直角三角形であり、第二廻り踏板３２は平面視で一つの角だけが直角の四角形である。 The rotating treads 30 are, in order from the top, the first rotating tread 31, the second rotating tread 32, and the third rotating tread 33. That is, the lower one step of the first round tread 31 is the second round tread 32, and the lower one step of the second round tread 32 is the third round tread 33.
The stair tread 30 in the present embodiment has the same shape as the conventional stair tread. That is, the first round tread 31 and the third round tread 33 are right-angled triangles in a plan view, and the second round tread 32 is a quadrangle in which only one corner is right-angled in a plan view.

廻りササラ桁４０は、第一桁部材４１、第二桁部材４２及び第三桁部材４３からなり、それらは全て基本板厚が７２ｍｍの木製材である。 The peripheral sasara girder 40 is composed of a first girder member 41, a second girder member 42, and a third girder member 43, all of which are wooden materials having a basic plate thickness of 72 mm.

第一桁部材４１は、図１に示すように板材であり、直線階段１００と同じ方向（前後方向）に延びるように三段廻り階段２００における外周側に立設配置される。
ここでの外周側とは三段廻り階段２００における左側である。
第一桁部材４１は、第一本体部４１ａと、第一本体部４１ａの前端から下方に突出する脚部４１ｃと、第一本体部４１ａの下部後端から後方に突出する後方突出部４１ｂと、を備える。
第一本体部４１ａの下端と後方突出部４１ｂの下端は高さ位置が一致しており、後方突出部４１ｂの上端は第一本体部４１ａの高さ位置の略中央である。 As shown in FIG. 1, the first girder member 41 is a plate material, and is erected on the outer peripheral side of the three-step round staircase 200 so as to extend in the same direction (front-back direction) as the straight staircase 100.
The outer peripheral side here is the left side of the three-step round staircase 200.
The first girder member 41 includes a first main body portion 41a, a leg portion 41c protruding downward from the front end of the first main body portion 41a, and a rear protruding portion 41b protruding rearward from the lower rear end of the first main body portion 41a. , Equipped with.
The lower end of the first main body portion 41a and the lower end of the rear protruding portion 41b have the same height position, and the upper end of the rear protruding portion 41b is substantially the center of the height position of the first main body portion 41a.

また、第一本体部４１ａの後端（後方突出部４１ｂが無い部分）は右方から左方に向かって後方に突出している。
第一桁部材４１の第一本体部４１ａには第一廻り踏板３１が上載され、後方突出部４１ｂには第二廻り踏板３２が上載される。このとき、第一本体部４１ａの後端に形成された斜面に第二廻り踏板３２を沿わせて配置される。 Further, the rear end of the first main body portion 41a (the portion without the rear protruding portion 41b) protrudes rearward from the right side to the left side.
The first round tread 31 is mounted on the first main body portion 41a of the first girder member 41, and the second round tread 32 is mounted on the rear protruding portion 41b. At this time, the second round tread 32 is arranged along the slope formed at the rear end of the first main body portion 41a.

第二桁部材４２は、図２に示すように板材であり、直線階段１００と垂直方向（左右方向）に延びるように三段廻り階段２００における外周側に立設配置される。
第二桁部材４２は、第二本体部４２ａと、第二本体部４２ａの上端から上方に突出する第二上部４２ｂと、を備える。
第二上部４２ｂの左端は、第二本体部４２ａの左端から第二桁部材４２の厚さ分だけ右に位置する。また、第二上部４２ｂの高さ（第二本体部４２ａの上端からの高さ）は第二本体部４２ａの高さよりも若干高い。
また、第二上部４２ｂの右端は、後方から前方に向かって右方に突出している。 As shown in FIG. 2, the second girder member 42 is a plate material, and is vertically arranged on the outer peripheral side of the three-step round staircase 200 so as to extend in the direction perpendicular to the straight staircase 100 (left-right direction).
The second girder member 42 includes a second main body portion 42a and a second upper portion 42b protruding upward from the upper end of the second main body portion 42a.
The left end of the second upper portion 42b is located to the right by the thickness of the second girder member 42 from the left end of the second main body portion 42a. Further, the height of the second upper portion 42b (height from the upper end of the second main body portion 42a) is slightly higher than the height of the second main body portion 42a.
Further, the right end of the second upper portion 42b projects to the right from the rear to the front.

第二桁部材４２の第二本体部４２ａの左端に、第一桁部材４１の後方突出部４１ｂの後端が上から重ねられる。つまり、第一桁部材４１と第二桁部材４２の互いに接する側の端部が互いに上下に重ねされて接合される。
また、第二上部４２ｂには第二廻り踏板３２が上載され、第二本体部４２ａには第三廻り踏板３３が上載される。このとき、第二上部４２ｂの右端の斜面には第三廻り踏板３３を添わせて配置される。 The rear end of the rear protruding portion 41b of the first girder member 41 is overlapped with the left end of the second main body portion 42a of the second girder member 42 from above. That is, the ends of the first girder member 41 and the second girder member 42 on the side where they are in contact with each other are overlapped and joined to each other.
Further, the second step plate 32 is mounted on the second upper portion 42b, and the third step plate 33 is mounted on the second main body portion 42a. At this time, the third round tread 33 is arranged along the slope at the right end of the second upper portion 42b.

第三桁部材４３は、図３に示すように平面視略Ｌ字状であり、三段廻り階段２００における内周側に立設配置される。
また、第三桁部材４３は、第三本体部４３ａと、第三本体部４３ａの後端から右方に突出する右方突出部４３ｂと、第三中間部４３ｃと、を備える。
右方突出部４３ｂ、第三中間部４３ｃ、第三本体部４３ａが下から順に一段目、二段目、三段目を構成する。
右方突出部４３ｂの後端は、右方から左方に向かって後方に突出している。ここで形成される斜面に沿って第二廻り踏板３２が配置される。右方突出部４３ｂの高さは第三本体部４３ａの高さの略１／３である。
また、第三中間部４３ｃは後方から前方に向かって右方に突出している。ここで形成されてる斜面に沿って第三廻り踏板３３が配置される。第三中間部４３ｃの高さは第三本体部４３ａの高さの略２／３である。
また、第三本体部４３ａの前端には直線階段１００の右側の直線ササラ桁１が上載されるとともに、第三本体部４３ａの前端以外の部分には第一廻り踏板３１が上載される。
また、第三桁部材４３は、図１３に示すように平面視略台形状で、上記同様に各廻り踏み板が配置されるための加工を施してあるものでも良く、さまざまな平面形状が考えられる。 As shown in FIG. 3, the third girder member 43 has a substantially L-shape in a plan view, and is vertically arranged on the inner peripheral side of the three-step round staircase 200.
Further, the third girder member 43 includes a third main body portion 43a, a right protruding portion 43b projecting to the right from the rear end of the third main body portion 43a, and a third intermediate portion 43c.
The right protruding portion 43b, the third intermediate portion 43c, and the third main body portion 43a constitute the first stage, the second stage, and the third stage in this order from the bottom.
The rear end of the right protruding portion 43b projects rearward from the right to the left. The second round tread 32 is arranged along the slope formed here. The height of the right protruding portion 43b is approximately 1/3 of the height of the third main body portion 43a.
Further, the third intermediate portion 43c projects to the right from the rear to the front. The third round tread 33 is arranged along the slope formed here. The height of the third intermediate portion 43c is approximately 2/3 of the height of the third main body portion 43a.
Further, a straight line sasara girder 1 on the right side of the straight staircase 100 is mounted on the front end of the third main body portion 43a, and a first stair tread 31 is mounted on a portion other than the front end of the third main body portion 43a.
Further, the third girder member 43 may have a substantially trapezoidal shape in a plan view as shown in FIG. 13, and may be processed for arranging the surrounding treads in the same manner as described above, and various plane shapes can be considered. ..

廻りササラ桁４０はこのように構成及び配置されるので、図５に示すように第二桁部材４２と第三桁部材４３との間には空隙Ｓが形成される。 Since the peripheral sasara girder 40 is configured and arranged in this way, a gap S is formed between the second girder member 42 and the third girder member 43 as shown in FIG.

ここで、直線ササラ桁１や廻り踏板３０からの視点で、それらがどこに配置されるか述べる。
直線階段１００の左側の直線ササラ桁１の下端は、第一桁部材４１の第一本体部４１ａの前部に上載されるとともに固定される。
直線階段１００の右側の直線ササラ桁１の下端は、第三桁部材４３の第三本体部４３ａの前端に上載されるとともに固定される。
そして、三段廻り階段２００に対する直線ササラ桁１の固定位置は前後に微調整可能である。 Here, it will be described where they are arranged from the viewpoint of the straight line Sasara girder 1 and the stair tread 30.
The lower end of the straight sasara girder 1 on the left side of the straight staircase 100 is placed on and fixed to the front portion of the first main body portion 41a of the first girder member 41.
The lower end of the straight line Sasara girder 1 on the right side of the straight staircase 100 is placed on and fixed to the front end of the third main body portion 43a of the third girder member 43.
The fixed position of the straight line Sasara girder 1 with respect to the three-step round staircase 200 can be finely adjusted back and forth.

第一廻り踏板３１は、第一桁部材４１の第一本体部４１ａと第三桁部材４３の第三本体部４３ａに架け渡すように上載されるとともに固定される。
第二廻り踏板３２は、第一桁部材４１の後方突出部４１ｂと第二桁部材４２の第二上部４２ｂ、第三桁部材４３の第三中間部４３ｃに架け渡すように上載されるとともに固定される。
第三廻り踏板３３は、第二桁部材４２の第二本体部４２ａと第三桁部材４３の右方突出部４３ｂに架け渡すように上載されるとともに固定される。 The first stair tread 31 is mounted and fixed so as to be bridged between the first main body portion 41a of the first girder member 41 and the third main body portion 43a of the third girder member 43.
The second round tread 32 is mounted and fixed so as to be bridged over the rear protruding portion 41b of the first girder member 41, the second upper portion 42b of the second girder member 42, and the third intermediate portion 43c of the third girder member 43. Will be done.
The third round tread 33 is mounted and fixed so as to be bridged over the second main body portion 42a of the second girder member 42 and the right protruding portion 43b of the third girder member 43.

次に、三段廻り階段２００に接続される直線階段１００について説明する。
この直線階段１００自体は、通常の露出階段であり、左右の直線ササラ桁１と踏板からなる。そして、直線ササラ桁１の上部の接続端部１ａに取り付けられる接続部材１０，２０に特徴を有する。
接続部材１０，２０は、これを介して直線階段１００を階上構造部材２に取り付けるものであり、第一接続金具１０と、第二接続金具２０と、を備える。 Next, the straight staircase 100 connected to the three-step round staircase 200 will be described.
The straight staircase 100 itself is a normal exposed staircase, and is composed of left and right straight line Sasara girders 1 and treads. The connecting members 10 and 20 attached to the connecting end portion 1a at the upper part of the straight line Sasara girder 1 are characterized.
The connecting members 10 and 20 attach the straight stairs 100 to the upstairs structural member 2 via the connecting members 10, 20 and include a first connecting metal fitting 10 and a second connecting metal fitting 20.

第一接続金具１０は、図７に示すように第一本体板１１と、二枚の第一側板１２と、第一上板１３と、係止部１５と、を備える金属部材である。
第一本体板１１は鉛直方向に延び、縦に二つの取付孔（図示しない）が形成されている。この取付孔を介して第一接続金具１０は直線ササラ桁１の取付溝１ｂの奥壁に取り付けられる。
第一側板１２は、二枚あり、それぞれが第一本体板１１の左右両端から前方に向かって立設し互いに向かい合う。また、第一側板１２の相対する位置にそれぞれ支持孔１２ａが形成されている。 As shown in FIG. 7, the first connection fitting 10 is a metal member including a first main body plate 11, two first side plates 12, a first upper plate 13, and a locking portion 15.
The first main body plate 11 extends in the vertical direction, and two mounting holes (not shown) are formed vertically. The first connection fitting 10 is attached to the back wall of the attachment groove 1b of the straight line Sasara girder 1 through this attachment hole.
There are two first side plates 12, each of which stands forward from the left and right ends of the first main body plate 11 and faces each other. Further, support holes 12a are formed at opposite positions of the first side plate 12.

第一上板１３は、第一本体板１１の上端から前方に向かって立設する。第一上板１３の下面は第一側板１２の上端からは離間している。また、第一上板１３の略中央に孔が形成されている。
第一本体板１１と二枚の第一側板１２と第一上板１３は一枚の金属の板状部材をプレス加工によって一体的に形成してなる。これらの厚さは３ｍｍである。 The first upper plate 13 is erected from the upper end of the first main body plate 11 toward the front. The lower surface of the first upper plate 13 is separated from the upper end of the first side plate 12. Further, a hole is formed substantially in the center of the first upper plate 13.
The first main body plate 11, the two first side plates 12, and the first upper plate 13 are formed by integrally forming a single metal plate-shaped member by press working. These thicknesses are 3 mm.

係止部１５は、直径が第一側板１２の支持孔１２ａの直径未満で略等しい棒状部材である。そして、左右方向に延びるように第一側板１２の支持孔１２ａを挿通し、渡すようにして二つの支持孔１２ａによって支持される。このとき、係止部１５は支持孔１２ａに通しただけであり、係止部１５と第一側板１２とは固定していない。
また、係止部１５の長さは第一側板１２の外側表面間の距離と略等しく、二つの支持孔１２ａに係止部１５を挿通した状態では第一側板１２の外側表面から係止部１５が突出せず、係止部１５の先端が第一側板１２の外側表面と面一になっている。 The locking portion 15 is a rod-shaped member having a diameter smaller than or substantially equal to the diameter of the support hole 12a of the first side plate 12. Then, the support hole 12a of the first side plate 12 is inserted so as to extend in the left-right direction, and is supported by the two support holes 12a so as to pass through. At this time, the locking portion 15 is only passed through the support hole 12a, and the locking portion 15 and the first side plate 12 are not fixed.
Further, the length of the locking portion 15 is substantially equal to the distance between the outer surfaces of the first side plate 12, and when the locking portion 15 is inserted through the two support holes 12a, the locking portion is locked from the outer surface of the first side plate 12. 15 does not protrude, and the tip of the locking portion 15 is flush with the outer surface of the first side plate 12.

第二接続金具２０は、図８に示すように第二本体板２１と、二枚の第二側板２２と、第二上板２３と、を備える金属部材である。
第二本体板２１は、鉛直方向に延び、縦に二つの取付孔が形成されている。この取付孔を介して第二接続金具２０は階上構造部材２に取り付けられる。 As shown in FIG. 8, the second connection fitting 20 is a metal member including a second main body plate 21, two second side plates 22, and a second upper plate 23.
The second main body plate 21 extends in the vertical direction, and two mounting holes are formed vertically. The second connection fitting 20 is attached to the upstairs structural member 2 through this attachment hole.

第二側板２２は、二枚あり、それぞれが第二本体板２１の左右両端から後方に向かって立設し互いに向かい合う。
第二側板２２は、上方が開口するように略Ｕ字状の案内溝２２ａが形成された受けフックをそれぞれ構成しており、第二側板２２自体の形状は略Ｊ字状となっている。
また、受けフックの案内溝２２ａはその下部において上方から下方になるにつれて僅かに前方に向かうように形成されている。
第二側板２２の外側表面間の距離は、第一側板１２の内側表面間の距離よりも短い。 There are two second side plates 22, each of which stands rearward from the left and right ends of the second main body plate 21 and faces each other.
The second side plate 22 each constitutes a receiving hook in which a substantially U-shaped guide groove 22a is formed so as to open upward, and the shape of the second side plate 22 itself is substantially J-shaped.
Further, the guide groove 22a of the receiving hook is formed so as to slightly move forward from the upper side to the lower side in the lower portion thereof.
The distance between the outer surfaces of the second side plate 22 is shorter than the distance between the inner surfaces of the first side plate 12.

第二上板２３は、第二本体板２１の上端から後方に向かって立設しており、第二上板２３の下面は第二側板２２の上端からは離間している。
このような第二本体板２１と二枚の第二側板２２と第二上板２３は、一枚の金属の板状部材をプレス加工によって一体的に形成してなる。これらの厚みも３ｍｍである。
第二上板２３の略中央に雌ネジ２３ａが形成されている。つまり、第二上板２３の略中央に孔が形成されるとともにその孔にタップが切られている。
この雌ネジ２３ａの位置は、第一接続金具１０と第二接続金具２０との嵌合時において第一上板１３の孔１３ａ直下となる第二上板２３の部分である。 The second upper plate 23 stands rearward from the upper end of the second main body plate 21, and the lower surface of the second upper plate 23 is separated from the upper end of the second side plate 22.
Such a second main body plate 21, two second side plates 22, and a second upper plate 23 are integrally formed by pressing a single metal plate-shaped member. These thicknesses are also 3 mm.
A female screw 23a is formed substantially in the center of the second upper plate 23. That is, a hole is formed substantially in the center of the second upper plate 23, and a tap is cut in the hole.
The position of the female screw 23a is a portion of the second upper plate 23 that is directly below the hole 13a of the first upper plate 13 when the first connecting metal fitting 10 and the second connecting metal fitting 20 are fitted.

このように構成された接続部材１０，２０が用いられる直線階段１００の階上構造部材２への取付構造について説明する。
直線ササラ桁１は直線階段１００において左右それぞれに配置される。ここでは左右一方について説明する。
直線ササラ桁１の上部の接続端部１ａには、上方及び前方に開口する取付溝１ｂが形成されている。一方、接続端部１ａは下方には開口していない。取付溝１ｂ自体の形状は直方体状である。 The mounting structure of the straight staircase 100 to which the connecting members 10 and 20 configured in this way are used will be described.
The straight line Sasara girder 1 is arranged on each of the left and right sides of the straight staircase 100. Here, one of the left and right sides will be described.
A mounting groove 1b that opens upward and forward is formed at the connection end portion 1a at the upper portion of the straight line Sasara girder 1. On the other hand, the connection end 1a is not open downward. The shape of the mounting groove 1b itself is a rectangular parallelepiped.

このような取付溝１ｂから第一接続金具１０が突出（露出）しないように第一接続金具１０はコーチボルトによって装着される。
一方、第二本体板２１がコーチボルトによって階上構造部材２に取り付けられる。 The first connection fitting 10 is mounted by a coach bolt so that the first connection fitting 10 does not protrude (expose) from such a mounting groove 1b.
On the other hand, the second main body plate 21 is attached to the upstairs structural member 2 by a coach bolt.

そして、図９に示すように係止部１５を受けフック２２の案内溝２２ａ内に落とし込むことで第一接続金具１０を第二接続金具２０と嵌合させるとともに、ボルトＢを第一上板１３の孔１３ａを介して第二上板２３の雌ネジ２３ａに対して螺合させる。
最後に、踏板をササラ桁１の接続端部１ａの上面に木ねじによって着脱自在に取付ける。更に、木ねじの頭を踏板に埋め込んで隠すために頭の上部に着脱可能な蓋を施しても良い。 Then, as shown in FIG. 9, the locking portion 15 is received and dropped into the guide groove 22a of the hook 22 to fit the first connection fitting 10 to the second connection fitting 20, and the bolt B is attached to the first upper plate 13. It is screwed into the female screw 23a of the second upper plate 23 through the hole 13a.
Finally, the tread is detachably attached to the upper surface of the connection end 1a of the Sasara girder 1 by a wood screw. Further, a removable lid may be provided on the upper part of the head in order to embed the head of the wood screw in the tread and hide it.

この第一接続金具１０と第二接続金具２０とが強固に嵌合可能なことにより、直線ササラ桁１の荷重によって三段廻り階段２００が水平移動してしまわないだけの接続強度を有している。すなわち、接続部材１０，２０が直線階段１００の荷重の水平成分を受けている。
また、第一接続金具１０と第二接続金具２０とをボルトＢにて螺合することにより、上下方向に地震などで力が加わった場合でも、金具が外れることを防ぐ構造となっている。さらに、ササラ桁上端に踏み板が設置されることで、取付溝１ｂの上部が踏板でふさがれるので、ボルトＢが緩んだ場合でもボルトＢが長ければボルトＢの頭部が踏板に当ることで、抜けることも防止される。 Since the first connection fitting 10 and the second connection fitting 20 can be firmly fitted, the connection strength is such that the three-step round staircase 200 does not move horizontally due to the load of the straight Sasara girder 1. There is. That is, the connecting members 10 and 20 receive the horizontal component of the load of the straight staircase 100.
Further, by screwing the first connecting metal fitting 10 and the second connecting metal fitting 20 with the bolt B, the metal fitting is prevented from coming off even when a force is applied in the vertical direction due to an earthquake or the like. Furthermore, by installing the tread on the upper end of the Sasara girder, the upper part of the mounting groove 1b is blocked by the tread, so even if the bolt B is loose, if the bolt B is long, the head of the bolt B will hit the tread. It is also prevented from coming off.

以上のように構成された露出階段構造によれば、三段廻り階段２００も蹴込み板を有さない露出階段で、しかも第一桁部材４１、第二桁部材４２及び第三桁部材４３は全て木製なので、その上部に接続される露出階段である直線階段１００と連続性があり、違和感が無い。
また、三段廻り階段２００は蹴込み板と他の支柱及び力桁受木を有さないので、図５に示すように構造が単純である。よって、三段廻り階段２００であっても直線階段１００の露出階段が持つ軽快感を有し、しかも内部の掃除が楽である。例えば、内部に掃除機のノズルや自動掃除機が容易に入り、またこのスペースに自動掃除機等を収納することも可能である。 According to the exposed staircase structure configured as described above, the three-step round staircase 200 is also an exposed staircase having no riser plate, and the first girder member 41, the second girder member 42, and the third girder member 43 are Since it is all made of wood, it has continuity with the straight staircase 100, which is an exposed staircase connected to the upper part, and there is no sense of discomfort.
Further, since the three-step round staircase 200 does not have a riser plate, other columns, and a force girder receiving tree, the structure is simple as shown in FIG. Therefore, even if it is a three-step round staircase 200, it has a light feeling that the exposed staircase of the straight staircase 100 has, and it is easy to clean the inside. For example, a vacuum cleaner nozzle or an automatic vacuum cleaner can be easily inserted inside, and an automatic vacuum cleaner or the like can be stored in this space .

また、直線階段１００の直線ササラ桁１の上部の接続端部１ａと、梁等の階上構造部材２と、が接続部材を介して接続され、接続部材１０，２０は、直線ササラ桁１の荷重によって三段廻り階段２００が水平移動してしまわないだけの接続強度を有するので、従来のものに比べて三段廻り階段２００に求められる強度が低い。
特に接続部材１０，２０は、凸状又は凹状の第一嵌合部１５を有し、取付溝１ｂから突出しないように取付溝１ｂに装着される第一接続金具１０と、第一接続金具１０の第一嵌合部１５と嵌合する凹状又は凸状の第二嵌合部２２を有し、階上構造部材２に取付けられる第二接続金具２０と、を備えるので、直線ササラ桁１の荷重によって三段廻り階段２００が水平移動してしまわないだけの接続強度となる。 Further, the connecting end portion 1a on the upper part of the straight sasara girder 1 of the straight staircase 100 and the floor structural member 2 such as a beam are connected via the connecting member, and the connecting members 10 and 20 are the straight sasara girder 1. Since the connection strength is such that the three-step round staircase 200 does not move horizontally due to the load, the strength required for the three-step round staircase 200 is lower than that of the conventional one.
In particular, the connecting members 10 and 20 have a convex or concave first fitting portion 15, and the first connecting fitting 10 mounted on the mounting groove 1b so as not to protrude from the mounting groove 1b, and the first connecting fitting 10 The linear sasara girder 1 has a second fitting portion 22 having a concave or convex shape to be fitted with the first fitting portion 15 of the above, and a second connection fitting 20 to be attached to the upstairs structural member 2. The connection strength is such that the three-step round staircase 200 does not move horizontally due to the load.

さらに、第一桁部材４１と第二桁部材４２の互いに接する側の端部を互いに上下に重ねて接合するので、三段廻り階段２００の強度を向上することができる。 Further, since the ends of the first girder member 41 and the second girder member 42 on the side where they are in contact with each other are vertically overlapped and joined to each other, the strength of the three-step round staircase 200 can be improved.

（第二実施形態）
図１０及び図１１を参照して、本発明の第二実施形態に係る露出階段構造を説明する。
図１０（ａ）は第一実施形態の第一桁部材４１を第一部材４１ｄと第二部材４１ｅの二つの部材からなるようにしたもので、図１１に示すように、第一部材４１ｄは左側の直線ササラ桁１の下端および第一廻り踏板３１を支え、第二部材４１ｅは、第一廻り踏板３１、第二廻り踏板３２および第二桁部材４２を支える。第一部材４１ｄと第二部材４１ｅの互いに接する側の端部を互いに上下に重ねてコーチボルト等で上下に接合すると強度的に優れる。 (Second embodiment)
The exposed staircase structure according to the second embodiment of the present invention will be described with reference to FIGS. 10 and 11.
FIG. 10A shows the first girder member 41 of the first embodiment made of two members, the first member 41d and the second member 41e, and as shown in FIG. 11, the first member 41d is The lower end of the straight Sasara girder 1 on the left side and the first round tread 31 are supported, and the second member 41e supports the first round tread 31, the second round tread 32 and the second girder member 42. It is excellent in strength when the ends of the first member 41d and the second member 41e on the side where they are in contact with each other are vertically overlapped with each other and joined vertically with a coach bolt or the like.

この際、第一桁部材４１の第一部材４１ｄの木質繊維方向を鉛直方向とし、例えば第二部材４１ｅは直線ササラ桁１と同様の繊維方向あるいは階段の傾斜方向と同様の繊維方向を持つ部材とすることで、直線ササラ桁１からの圧縮加重に対する強度を確保した上で、傾斜方向の力にも耐え、かつ、必要な木材の幅を抑えた木取りができる様になり、コストも低減され、デザインの自由度も増すことが出来る。
図１０（ｂ）は第一実施形態に係る第二桁部材４２の変形例であり、第二廻り踏板３２、第三廻り踏板３３を支える。 At this time, the wood fiber direction of the first member 41d of the first girder member 41 is the vertical direction, and for example, the second member 41e is a member having the same fiber direction as the straight Sasara girder 1 or the same fiber direction as the inclined direction of the stairs. By doing so, it becomes possible to secure the strength against the compression load from the straight Sasara girder 1, to withstand the force in the inclined direction, and to reduce the required width of the wood, and the cost is also reduced. , The degree of freedom in design can also be increased.
FIG. 10B is a modified example of the second girder member 42 according to the first embodiment, and supports the second round tread plate 32 and the third round tread plate 33.

これら第一桁部材４１の第二部材４１ｅと第二桁部材４２との支える関係は、第一実施形態の場合とは逆となっており、第二桁部材４２の左端下部を切り欠いた場合、第一桁部材４１の加重を支えることが出来ないので、支え方を逆にして第一桁部材４１を接地させ、第二桁部材４２をこの上に置いて支える設計とした。
図１０（ｃ）は第一実施形態の第三桁部材４３の変形例であり、側面略台形形状をして、第一桁部材４１の第一部材４１ｄと同様のデザインとし、デザインの統一性を高めている。また、繊維方向を第一桁部材４１の第一部材４１ｄ同様に鉛直方向としている。 The relationship of supporting the second member 41e of the first girder member 41 and the second girder member 42 is opposite to that of the first embodiment, and the lower left end of the second girder member 42 is cut out. Since it is not possible to support the load of the first girder member 41, the support method is reversed so that the first girder member 41 is grounded and the second girder member 42 is placed on this to support it.
FIG. 10C is a modification of the third girder member 43 of the first embodiment, in which the side surface is substantially trapezoidal and has the same design as the first member 41d of the first girder member 41. Is increasing. Further, the fiber direction is set to the vertical direction as in the first member 41d of the first girder member 41.

第一桁部材の第一部材４１ｄ、第二部材４１ｅや、第三桁部材４３などに使用する木質材料は、所定の繊維方向で使用するのが好ましく、例えば、無垢の木材、集成材、単板積層材などを用いると良い。
積層した木質材料を使用する場合、主たる繊維方向を所定方向に向けることで、同様に好適に使用でき、一部の合板や、配向性ストランドボードなどで繊維方向の多数を同一方向に配向したものは、強度を考慮して使用可能である。
このように、廻りササラ桁４０（４１，４２，４３）は適宜その構成及び配置を変形することが出来る。 The wood material used for the first member 41d, the second member 41e, the third girder member 43, etc. of the first girder member is preferably used in a predetermined fiber direction, for example, solid wood, laminated wood, veneer. It is advisable to use a board laminated material or the like.
When using laminated wood-based materials, it can be used similarly favorably by directing the main fiber direction to a predetermined direction, and some plywood, oriented strand board, etc. with many fiber directions oriented in the same direction. Can be used in consideration of strength.
In this way, the peripheral sasara girder 40 (41, 42, 43) can be appropriately modified in its configuration and arrangement.

次に図１２を参照して、本願発明の露出階段の、廻り階段と直線階段の施工について説明する。
まず、三段廻り階段２００を施工する。次に階上構造部材２に接続部材の一方である第二接続金具２０を所定の位置に取り付ける。直線ササラ桁１には予め所定の位置に接続部材の他方である第一接続金具１０を取り付けておく。 Next, with reference to FIG. 12, the construction of the circular staircase and the straight staircase of the exposed staircase of the present invention will be described.
First, the three-step round staircase 200 is constructed. Next, the second connecting fitting 20, which is one of the connecting members, is attached to the upstairs structural member 2 at a predetermined position. The first connecting metal fitting 10, which is the other side of the connecting member, is attached to the straight line Sasara girder 1 in advance at a predetermined position.

この状態で、直線ササラ桁１の下端を廻りササラ桁４０に載せると共に、その上部の接続部１ａの取付溝１ｂの第一接続端部１０に、階上構造部材２に取り付けてある第二接続部材２０を差込み、直線ササラ桁１を上方から下ろしながら階上構造部材２に近付けることで、接続部材１０，２０をはめ込む。
次に直線ササラ桁１の下端を、コーチボルトＣを用いて廻りササラ桁４０に固定すると共に、直線ササラ桁１上端の接続部材１０，２０同士を、ボルトＢを締めて固定する。
この様に、長尺で、重量のある、直線ササラ桁１を、廻りササラ桁４０の上に載せながら梁２にも固定することが、接続部材１０，２０の使用による容易な位置決めと、その架台となる廻りササラ桁４０の支えとで、容易に行えるようになった。 In this state, the lower end of the straight line Sasara girder 1 is rotated and placed on the Sasara girder 40, and the second connection attached to the upper structural member 2 at the first connection end portion 10 of the mounting groove 1b of the connection portion 1a above the straight line Sasara girder 1. The connecting members 10 and 20 are fitted by inserting the member 20 and bringing the straight line Sasara girder 1 closer to the upstairs structural member 2 while lowering it from above.
Next, the lower end of the straight line sasara girder 1 is fixed to the rotating sasara girder 40 by using a coach bolt C, and the connecting members 10 and 20 at the upper ends of the straight line sasara girder 1 are fixed by tightening the bolts B.
In this way, the long and heavy straight line Sasara girder 1 can be fixed to the beam 2 while being placed on the rotating Sasara girder 40, and easy positioning by using the connecting members 10 and 20 and its positioning. With the support of the rotating Sasara girder 40 that serves as a stand, it has become easier to do.

上記の手順の三段廻り階段の施工は、次のように行うことも出来る。
三段廻り階段２００を、廻りササラ桁４０と第一廻り踏板３１、第二廻り踏板３２を組み上げる事で変形しない枠組みとする。この状態で床には固定しないで、所定位置に置いた上で、上記の直線ササラ桁１の設置をし、直線ササラ桁１の下端を廻りササラ桁４０に上載し固定する。その後、第二桁部材４２（図１０（ｂ））の右端をコーチボルトで、各廻りササラ桁４１，４２，４３を金具などにて、床に固定し、その上で第三廻り踏板３３を設置することで、階上構造部材２を基準として、直線階段、廻り階段の位置が順に定まって行くように施工され、細かな誤差を吸収した位置合わせが容易に行えた。 The construction of the three-step stairs in the above procedure can also be performed as follows.
The three-step round staircase 200 is made into a framework that does not deform by assembling the round sasara girder 40, the first round tread 31, and the second round tread 32. In this state, the straight line Sasara girder 1 is installed after being placed in a predetermined position without being fixed to the floor, and the lower end of the straight line Sasara girder 1 is placed around the lower end of the straight line Sasara girder 1 and fixed on the Sasara girder 40. After that, the right end of the second girder member 42 (FIG. 10 (b)) is fixed to the floor with a coach bolt, and the surrounding sasara girders 41, 42, 43 are fixed to the floor with metal fittings or the like, and the third round tread 33 is placed on the floor. By installing the stairs, the positions of the straight stairs and the round stairs were determined in order based on the upper floor structural member 2, and the alignment was easily performed by absorbing small errors.

この誤差は、直線ササラ桁１を取り付ける階上構造部材２である梁の面の鉛直面からの傾きや、それを支える柱のわずかな傾き、床高さの誤差などの集積で、設計状態とは異なる配置となることから生じる。階段はその全長が長いので、これらのわずかな誤差の集積でも端部では大きな誤差が生じやすいので、この様に現場でのあわせが容易な様に施工できる本願の階段構造は大きな利点となる。
また、三段廻り階段２００を組み立てた後は、この全体で直線ササラ桁１から加わる力を支えることとなり、第一桁部材４１と第三桁部材４３の直線ササラ桁１直下で支持するのみならず、第一桁部材４１や第二桁部材４２にある床などへの設置する部分や、これらの固定金具などでもこの力を分散して支える。
廻りササラ桁４０は、直下の床を大引き、束などで下支えされた設置面に設置されている。
上記ササラ桁１，４０の固定後に、直線階段の踏板や手摺、化粧材などの施工を行い、階段を完成させる。 This error is due to the accumulation of the inclination of the beam, which is the floor structural member 2 to which the straight Sasara girder 1 is attached, from the vertical surface, the slight inclination of the columns supporting it, and the error of the floor height. Arises from the different arrangements. Since the total length of the stairs is long, even if these slight errors are accumulated, a large error is likely to occur at the end. Therefore, the staircase structure of the present application, which can be constructed so as to be easily adjusted on site, is a great advantage.
Further, after assembling the three-step round staircase 200, the force applied from the straight Sasara girder 1 will be supported as a whole, and if it is only supported directly under the straight Sasara girder 1 of the first girder member 41 and the third girder member 43. Instead, this force is distributed and supported by the parts to be installed on the floor of the first girder member 41 and the second girder member 42, and the fixing metal fittings thereof.
The rotating Sasara girder 40 is installed on an installation surface that is supported by a bundle or the like by pulling the floor directly underneath.
After fixing the Sasara girders 1 and 40, the stairs are completed by constructing the treads, handrails, decorative materials, etc. of the straight stairs.

（第三実施形態）
露出階段には従来から、片側をササラ桁１で、他方を壁の構造材にて、その踏板を支える様にした直線階段がある。この場合、直線ササラ桁１は片側のみであるが、これを廻り階段の廻りササラ桁４３の片側で受ける構造に応用できる。
すなわち、廻り階段の外側にあたる部分が壁の場合は、廻りササラ桁の第一桁部材４１の役割が壁の構造材で行われるので、その場合の三段廻り階段は、第二桁部材４２、第三桁桁部材４３、および、各廻り踏板３１，３２，３３で構成される。直線ササラ桁１は、第三桁部材４３で支えられる。
廻り階段の内側にあたる部分が壁（直線階段の部分が壁）の場合は、廻りササラ桁４０の第三桁部材４３の役割が壁の構造材で行われることも可能なので、その場合の三段廻り階段は、第一桁部材４１、第二桁部材４２、及び各廻り踏板３１，３２，３３で構成される。このとき、直線ササラ桁１は、第一桁部材４１で支えられる。
いずれにしても、直線ササラ桁の施工は、これまでの実施例と同様に行える。 (Third embodiment)
Conventionally, the exposed stairs have a straight staircase in which one side is a sasara girder 1 and the other side is a structural material of a wall to support the tread. In this case, the straight line Sasara girder 1 is only on one side, but it can be applied to a structure in which it is received on one side of the round stairs around the Sasara girder 43.
That is, when the part corresponding to the outside of the round staircase is a wall, the role of the first girder member 41 of the round sasara girder is played by the structural material of the wall. It is composed of a third-girder girder member 43 and tread plates 31, 32, 33, respectively. The straight line Sasara girder 1 is supported by the third girder member 43.
When the part corresponding to the inside of the round stairs is a wall (the part of the straight stairs is the wall), the role of the third girder member 43 of the round sasara girder 40 can be played by the structural material of the wall, so the three steps in that case. The round staircase is composed of a first girder member 41, a second girder member 42, and round treads 31, 32, 33. At this time, the straight line Sasara girder 1 is supported by the first girder member 41.
In any case, the construction of the straight Sasara girder can be performed in the same manner as in the previous embodiments.

なお、以上の実施形態において、第一接続金具１０と第二接続金具２０からなる接続部材１０，２０によって直線階段１００を階上構造部材２に接続したが、これに限られるものではなく、直線階段１００を階上構造部材２に強固に接続可能であれば他の方法を採用してもよい。 In the above embodiment, the straight staircase 100 is connected to the upstairs structural member 2 by the connecting members 10 and 20 composed of the first connecting fitting 10 and the second connecting fitting 20, but the present invention is not limited to this and is a straight line. Other methods may be adopted as long as the stairs 100 can be firmly connected to the upstairs structural member 2.

また、本願で言う「ササラ桁」は、独立した桁であるが、その上面で踏板を支えるもののみでなく、その側面に例えば溝を切り欠く、あるいは、金具を取り付けることで踏板を支える様な、桁でも可能である。しかし、独立した桁なので壁面に固定された側板は含まれない。 Further, the "Sasara girder" referred to in the present application is an independent girder, but it is not only a girder that supports the tread on its upper surface, but also a groove is cut out on the side surface thereof, or a metal fitting is attached to support the tread. , Digits are also possible. However, since it is an independent girder, the side plate fixed to the wall surface is not included.

上記の実施例では第二桁部材４２が、直線階段の方向から９０度の方向に置かれたが、周り階段のデザインに応じて、例えば７０度とするなど、より直線階段の方向を向いた（直線階段から鈍角に曲がる）廻り階段とすることもでき、この場合は踏み板３１，３２，３３がその開いた角度の分だけ長く、また形状を変えて設計されるなど、適宜変更される。
廻り階段の段数も３段以上にし廻りササラ桁、踏板の数を適宜変更してよい。 In the above embodiment, the second girder member 42 is placed in the direction of 90 degrees from the direction of the straight stairs, but depending on the design of the surrounding stairs, it faces the direction of the straight stairs more, for example, 70 degrees. It can also be a round staircase (turning at an obtuse angle from a straight staircase), and in this case, the tread plates 31, 32, 33 are lengthened by the open angle, and the shape is changed as appropriate.
The number of steps of the round stairs may be 3 or more, and the number of round sasara girders and treads may be changed as appropriate.

また、第一桁部材４１と第二桁部材４２の互いに接する側の端部を互いに上下に重ねて接合したが、これに限られるものではない。 Further, the ends of the first girder member 41 and the second girder member 42 on the side where they are in contact with each other are vertically overlapped and joined, but the present invention is not limited to this.

また、第三廻り踏板３３の高さ位置を本実施形態の係るものよりも高く設計した場合、第二桁部材４２の下部に空隙Ｓを形成してもよい。
このように設計変更した場合、各廻り踏板３０を廻りササラ桁４０によって支持可能なように各廻りササラ桁４０も適宜変更可能である。 Further, when the height position of the third round tread 33 is designed to be higher than that of the present embodiment, a gap S may be formed in the lower part of the second girder member 42.
When the design is changed in this way, each round sasara girder 40 can be appropriately changed so that each round tread 30 can be supported by the round sasara girder 40.

また、第一桁部材４１の脚部４１ｃを除いた下端を水平にしているが、例えばここを直線ササラ桁１が延びる方向と平行なデザインとなるように適宜変更してもよい。
同様に、第一桁部材４１の脚部４１ｃや第三桁部材４３の端面を鉛直ではなく角度を持たせるようにする等のデザイン上の変更は適宜行うことができる。 Further, although the lower end of the first girder member 41 excluding the leg portion 41c is horizontal, for example, the design may be appropriately changed so as to be parallel to the direction in which the straight line Sasara girder 1 extends.
Similarly, design changes such as making the legs 41c of the first girder member 41 and the end faces of the third girder member 43 have an angle instead of being vertical can be appropriately made.

さらには、廻り階段は三段廻り階段２００である必要は無く、四段廻り階段であってもよい。このとき、廻りササラ桁４０は廻り踏板３０を異なる高さにおいて支持可能なように適宜加工される。 Further, the round staircase does not have to be a three-step round staircase 200, and may be a four-step round staircase. At this time, the rotating sasara girder 40 is appropriately processed so that the rotating tread 30 can be supported at different heights.

また、第一桁部材４１、第二桁部材４２、第三桁部材４３を固定金具を用いてそれぞれ床に固定してもよい。
以上では、直線ササラ桁１を梁などの階上構造材２に取り付けると記載しているが、梁や柱などの階上構造部材２の表面に、石膏ボードや合板、更にはクロス貼りなどを行って表面仕上げ材が施された後に、第二接続金具２０を取り付けてササラ桁１を取り付ける場合でも同様の効果が生じる。 Further, the first girder member 41, the second girder member 42, and the third girder member 43 may be fixed to the floor using fixing metal fittings, respectively.
In the above, it is described that the straight Sasara girder 1 is attached to the upper floor structural material 2 such as a beam, but gypsum board, plywood, and further cloth is attached to the surface of the upper floor structural member 2 such as a beam and a pillar. The same effect is obtained when the second connection fitting 20 is attached and the gypsum gypsum 1 is attached after the surface finishing material is applied.

１直線ササラ桁
１ａ上部の接続端部
１ｂ取付溝
１ｃ欠き込み
１ｄ下部の接続端部
２階上構造部材（梁）
１０第一接続金具（接続部材）
１１第一本体板
１２第一側板
１２ａ支持孔
１３第一上板
１３ａ孔
１５係止部（第一嵌合部）
２０第二接続金具（接続部材）
２１第二本体板
２２第二側板（受けフック、第二嵌合部）
２２ａ案内溝
２３第二上板
２３ａ雌ネジ
３０廻り踏板
３１第一廻り踏板
３２第二廻り踏板
３３第三廻り踏板
４０廻りササラ桁
４１第一桁部材
４１ａ第一本体部
４１ｂ後方突出部
４１ｃ脚部
４１ｄ第一部材
４１ｅ第二部材
４２第二桁部材
４２ａ第二本体部
４２ｂ第二上部
４３第三桁部材
４３ａ第三本体部
４３ｂ右方突出部
４３ｃ第三中間部
１００直線階段
２００三段廻り階段（廻り階段）
Ｂボルト
Ｃコーチボルト
Ｓ空隙 1 Straight line Sasara girder 1a Upper connection end 1b Mounting groove 1c Notch 1d Lower connection end 2 Upstairs structural member (beam)
10 First connection fitting (connection member)
11 First main body plate 12 First side plate 12a Support hole 13 First upper plate 13a hole 15 Locking part (first fitting part)
20 Second connection fitting (connection member)
21 Second body plate 22 Second side plate (receiving hook, second fitting part)
22a Guide groove 23 Second upper plate 23a Female screw 30 Rotating step plate 31 First rotating tread 32 Second rotating tread 33 Third rotating tread 40 Circular Sasara girder 41 First girder member 41a First main body 41b Rear protrusion 41c Leg 41d 1st member 41e 2nd member 42 2nd girder member 42a 2nd main body 42b 2nd upper part 43 3rd girder member 43a 3rd main body 43b Right protruding part 43c 3rd intermediate part 100 Straight stairs 200 Three-step round stairs (Around the stairs)
B bolt C coach bolt S void

Claims

It is a staircase structure in which a three-step round staircase is connected to the bottom of a straight staircase that is an exposed staircase.
The three-step round staircase has a round sasara girder that supports a first round tread, a second round tread that is one step lower of the first round tread, and a third round tread that is one step lower of the second round tread.
The surrounding Sasara girder is
A first girder member that is arranged on the outer peripheral side of the three-step round staircase so as to extend in the same direction as the straight staircase and supports one of the straight tread plate, the second round tread plate, and the straight staircase. When,
A second girder member arranged on the outer peripheral side of the three-step round staircase so as to extend in the direction perpendicular to the straight staircase and supporting the second round tread and the third round tread.
Arranged on the inner peripheral side of the three-step round staircase, it has a substantially L-shaped plan view that supports the first round tread, the second round tread, the third round tread, and the other straight Sasara girder of the straight stair. With a third girder member,
The connecting end of the upper part of the straight Sasara girder of the straight staircase and the upstairs structural member are connected via the connecting member.
Further, the first girder member, the second girder member and the third girder member are all made of wood.
Moreover, the three-step round staircase has an exposed staircase structure that does not have a riser plate, other columns, and a force girder receiving tree.

At the connection end of the straight Sasara girder, mounting grooves that open upward and forward are formed, and at the same time,
The connecting member is
A first connection fitting having a convex or concave first fitting portion and mounted in the mounting groove so as not to protrude from the mounting groove.
It has a concave or convex second fitting portion that fits with the first fitting portion of the first connection fitting, and is characterized by comprising a second connection fitting that is attached to the floor structure member. The exposed staircase structure according to claim 1 .

The exposed staircase structure according to claim 1 or 2 , wherein the ends of the first girder member and the second girder member on the side where they are in contact with each other are vertically overlapped and joined to each other.

It is an exposed staircase structure in which a round staircase is connected to the bottom of a straight staircase.
The round staircase has a round tread and a round sasara girder that supports the round tread.
The surrounding Sasara girder is
The first girder member arranged on the outer peripheral side of the staircase so as to extend in the same direction as the straight staircase,
A second girder member arranged on the outer peripheral side of the staircase so as to extend in a direction different from that of the straight staircase.
A third girder member arranged on the inner peripheral side of the stairs is provided.
The connection end of the upper part of each of the left and right straight Sasara girders of the straight staircase and the upstairs structural member are connected via the connecting member, and are also connected.
The lower connecting end of one of the straight Sasara girders is connected to the upper part of the first girder member, and the lower connecting end of the other straight Sasara girder is connected to the upper part of the third girder member.
Moreover, the exposed staircase structure is characterized in that the lower portion of the portion of the first girder member and the third girder member to which the lower connection end of the straight Sasara girder is connected is supported by the installation surface.

It is an exposed staircase structure in which a round staircase is connected to the bottom of a straight staircase.
The round staircase has a round tread and a round sasara girder that supports the round tread.
The surrounding Sasara girder is
The first girder member arranged on the outer peripheral side of the staircase so as to extend in the same direction as the straight staircase,
A second girder member arranged on the outer peripheral side of the staircase so as to extend in a direction different from that of the straight staircase.
A third girder member arranged on the inner peripheral side of the stairs is provided.
The connection end of the upper part of each of the left and right straight Sasara girders of the straight staircase and the upstairs structural member are connected via the connecting member, and are also connected.
The lower connecting end of one of the straight Sasara girders is connected to the upper part of the first girder member, and the lower connecting end of the other straight Sasara girder is connected to the upper part of the third girder member.
Moreover, in the first girder member and the third girder member, the lower part of the portion where the connection end portion of the lower part of the straight line Sasara girder is connected is supported by the installation surface.
The first girder member is composed of a plurality of woody members. The member to which the connecting end of the lower part of the straight Sasara girder is connected is a woody member having a fiber direction in a substantially vertical direction, and the other members are in the inclined direction of the stairs. An exposed staircase structure characterized by including a wood member, which is in the fiber direction of the.

It is an exposed staircase structure in which a round staircase is connected to the bottom of a straight staircase.
The round staircase has a round tread and a round sasara girder that supports the round tread.
The surrounding Sasara girder is
A second girder member arranged on the outer peripheral side of the staircase so as to extend in a direction different from that of the straight staircase.
A third girder member arranged on the inner peripheral side of the stairs is provided.
The connecting end of the upper part of the straight Sasara girder of the straight staircase and the upstairs structural member are connected via the connecting member, and at the same time.
The lower connecting end of the straight Sasara girder is connected to the upper part of the third girder member.
Moreover, the exposed staircase structure is characterized in that the lower part of the portion of the third girder member to which the lower part of the straight line Sasara girder is connected is supported by the installation surface.