【０００１】
【発明の属する技術分野】
本発明はまくら木に係り、更に詳しくは、道床に対する位置ずれの発生を防止したまくら木に関する。また本発明は、まくら木表面の摩耗を抑えたまくら木に関する。
【０００２】
【従来の技術】
従来より、まくら木には、木製やＰＣ（Ｐｒｅｓｔｒｅｓｓｅｄ Ｃｏｎｃｒｅｔｅ）製のものが一般に使用されている。木製まくら木は、軽量で振動にも強いが、耐用年数が短く、軌道の道床抵抗が小さい欠点があり、木材資源の枯渇の面からも採用を控える傾向にある。一方、ＰＣ製まくら木は、曲げ荷重に対して強く耐用年数も長いが、重量が重く、敷設工事が大がかりになる嫌いがあり、更に、振動に弱いためにレールの分岐部等には不向きである。
【０００３】
そこで、近年、これらのまくら木に代わるものとして、繊維強化硬質合成樹脂発泡体を素材とした合成木材で製された合成まくら木が使用されている。合成まくら木は、軽くて強度があり耐久性に優れているだけでなく、振動にも強いのでレールの継ぎ目や分岐部に多用されている。
【０００４】
ところで、レールの継ぎ目や分岐部では列車の通過に伴う振動が大きく、軌道の圧密化が進んで軌道沈下が生じ、軌道が上下したり、まくら木が道床横方向（レールと交差する方向）や道床縦方向（レール方向）にずれを生じるといった所謂「あおり現象」が生じ易い。特に、合成まくら木は重量が軽いために「あおり現象」を生じ易い。そこで、合成木材製の分岐まくら木では、予め、底面に突条部材を取り付けたものを使用するなどして、まくら木の道床横方向への位置ずれを防止する対策が採られていた。
【０００５】
また、前記したように、分岐まくら木では「あおり現象」が生じ易く、まくら木上面では、タイプレートとの接触による摩擦摩耗によって凹みが生じたり、まくら木底面や側面では、バラストとの接触による摩擦摩耗によって凹みや損傷が発生する。そこで、「あおり現象」が生じ易い場所では、まくら木の表面にゴム板などの耐摩耗性部材を貼付して摩擦摩耗の発生を防止していた。
【０００６】
【発明が解決しようとする課題】
ところが、前記した突条部材を設けた合成まくら木は、道床横方向への位置ずれを防止する効果はあるものの、道床縦方向への位置ずれを防止する効果は殆ど期待できなかった。
また、まくら木の上下動や位置ずれに伴う摩擦摩耗を防止するための耐摩耗性部材（ゴム材）は高価なため、まくら木の上面に貼付することはあっても底面や側面にまで貼付されることは少なく、充分な耐摩耗効果が得られず耐久性に問題を残していた。
【０００７】
本発明はこのような問題に鑑みて提案されるもので、まくら木の道床縦方向や道床横方向への位置ずれを効果的に抑制するまくら木を提供することを目的としている。また、同時に提案される本発明は、コストを抑えつつ耐摩耗性を向上したまくら木を提供することを目的としている。
【０００８】
【課題を解決するための手段】
前記目的を達成するために提案される請求項１に記載のまくら木は、まくら木の底面に、当該まくら木の長手方向へ延びる突条を形成した構成とされている。
【０００９】
まくら木の底面に長手方向へ延びる突条を形成すると、まくら木を幅方向から見たときの高さは本体部分の高さに突条の高さを加えたものとなる。従って、まくら木を幅方向（道床縦方向）から見たときのバラスト接触面積が増加し、まくら木の位置ずれに抗するバラスト（道床）の抗力が増大して道床縦方向への位置ずれが抑制される。
【００１０】
本発明において、突条は、まくら木の底面の幅方向中央部に長手方向へ向けて設ける構成や、まくら木の底面の幅方向両端部近傍に長手方向へ向けて設ける構成を採ることができる。また、この突条は、まくら木の底面に長手方向全長に渡って設けても良く、長手方向の一部に設けても良い。また、長手方向へ延びる突条を複数設けることも可能である。
まくら木の底面に長手方向に延びる突条を設けると、まくら木の断面２次モーメントが増加し、長手方向の曲げ剛性（ＥＩ）を向上させることができる。
【００１１】
突条は、例えば、まくら木の底面に長手方向へ向けて角材を接合して形成することができる。また、従来サイズのまくら木よりも高さの高い角柱材を使用して、この角柱材の底面における突条の形成部位以外の部分を切削して突条を有するまくら木を形成することも可能である。
【００１２】
請求項２に記載の発明は、請求項１に記載のまくら木において、まくら木の長手両側面に、当該まくら木の高さ方向へ延びる突条を形成した構成とされている。
【００１３】
まくら木の長手両側面に高さ方向へ延びる突条を形成すると、まくら木を長手方向（道床横方向）から見たときの幅は本体部分の幅に突条の幅を加えたものとなる。従って、まくら木を道床横方向から見たときのバラスト接触面積が増加し、まくら木の位置ずれに抗するバラストの抗力が増大して道床横方向への位置ずれが抑制される。
【００１４】
本発明において、高さ方向へ延びる突条は、まくら木の長手両側面に高さ方向全長に渡って設けても良く、高さ方向の一部に設けても良い。また、高さ方向へ延びる突条を複数設けることも可能である。
突条は、例えば、まくら木の長手両側面に高さ方向へ向けて角材を接合して形成することができる。また、従来サイズのまくら木よりも幅の広い角柱材を使用して、この角柱材の長手両側面における突条の形成部位以外の部分を切削して突条を有するまくら木を形成することも可能である。
【００１５】
請求項３に記載の発明は、まくら木の底面に、当該まくら木の幅方向へ延びる突条を形成すると共に、まくら木の長手両側面に、当該まくら木の高さ方向へ延びる突条を形成した構成とされている。
【００１６】
まくら木の底面に幅方向へ延びる突条を形成すると、まくら木を長手方向から見たときの高さは本体部分の高さに突条の高さを加えたものとなる。従って、まくら木を長手方向（道床横方向）から見たときのバラスト接触面積が増加し、まくら木の位置ずれに抗するバラストの抗力が増大して道床横方向への位置ずれが抑制される。
【００１７】
また、まくら木の長手両側面に高さ方向へ延びる突条を形成すると、請求項２に記載のまくら木と同様の理由により、まくら木の道床横方向への位置ずれが抑制される。
則ち、本発明のまくら木によれば、まくら木の底面及び長手両側面に設けた突条により、まくら木の道床横方向への位置ずれを一層抑制することが可能となる。
【００１８】
請求項４に記載の発明は、請求項３に記載のまくら木において、まくら木の底面に幅方向へ延びる突条とまくら木の長手両側面に高さ方向へ延びる突条との端部同士を接続して一体的に形成した構成とされている。
【００１９】
本発明の構成によれば、まくら木の長手両側面から底面にかけてコ字状の突条が形成され、まくら木を長手方向から見たときの幅及び高さが増加してバラスト接触面積が増大する。これにより、まくら木の道床横方向への位置ずれに抗するバラストの抗力が増大して道床横方向への位置ずれが抑制される。
【００２０】
コ字状の突条を形成する構成としては、例えば、角材をまくら木の底面と長手両側面に接合して形成したり、あるいは、予め角材をコ字状に接合した突条部材を、まくら木の底面側から挿入して底面及び長手両側面に接合する構成を採ることも可能である。また、方形板材をコ字状に切削して形成された一体化した突条部材を用いることも可能である。
【００２１】
請求項５に記載の発明は、請求項１乃至４のいずれか１項に記載のまくら木において、突条は、レール又はタイプレートが固定されるまくら木の上面部位に対応した底面及び／又は長手両側面の部位近傍に設けられる構成とされている。
【００２２】
列車の通過に伴ってまくら木に加わる力は全てレール又はタイプレートを介して伝達される。このため、レールやタイプレートが固定される部位から離れた底面や長手両側面に突条を設けると、列車の通過に伴ってまくら木へ力が加わる部位とバラストの抗力が加わる突条の部位との間隔が開いてまくら木に撓みや挫屈が生じ易い。
【００２３】
本発明によれば、レールやタイプレートの固定部位に対応した底面や長手両側面に突条を設けるので、レールやタイプレートから伝達される力が加わる部位の近傍に突条による抗力が加わる。これにより、まくら木の撓みや挫屈の発生を抑えつつ、まくら木の道床横方向や道床縦方向への位置ずれを効果的に抑止することが可能である。
【００２４】
請求項６に記載の発明は、請求項１乃至５のいずれか１項に記載のまくら木において、突条は、当該突条のまくら木表面からの突出長が軌道上に敷設されるバラストの平均粒径と略等しい構成とされている。
【００２５】
ここで、まくら木表面からの突条の突出長がバラストの平均粒径に比べて著しく小さいときは、まくら木を長手方向又は幅方向から見たときのバラスト接触面積の増加が極めて少ない。このため、バラストの抗力の増加が少なく位置ずれの抑止効果の向上が期待できない。
一方、まくら木表面からの突条の突出長がバラストの平均粒径に比べて大きいときは、バラスト接触面積の増加によって位置ずれの抑止効果は向上するが、反面、突条の突出長の増加に伴ってまくら木の敷設作業性が著しく低下する。
【００２６】
まくら木表面からの突条の突出長はバラストの平均粒径と略等しくするのが良い。突条の突出長がバラストの平均粒径と略等しいときは、まくら木の表面に当接するバラストの突出長が突条の突出長と略等しくなり、突条の先端部にバラストの中央部が当接する状態が生じ難い。これにより、まくら木に長手方向や幅方向へ位置ずれを生じさせる力が加わったときに、突条の先端部がバラストを乗り越えてずれるような不具合が生じ難く、安定した抗力を受けて位置ずれを防止することが可能となる。
【００２７】
請求項７に記載の発明は、レール又はタイプレートが固定されるまくら木の上面部位、及び、当該上面部位に対応した底面及び長手両側面の部位に耐摩耗性部材を取り付けた構成とされている。
【００２８】
列車の通過に伴って、まくら木は下方や道床縦方向あるいは道床横方向へ向けて大きな力を受け、まくら木の底面の道床が圧密化して軌道が上下する所謂「あおり現象」が生じ易く、レールやタイプレートとの摩擦摩耗によってまくら木の上面に凹みが生じたり、バラストとの摩擦摩耗によってまくら木の底面や長手側面に凹みや損傷が生じ易い。
【００２９】
本発明によれば、前記したように、レール又はタイプレートが固定されるまくら木の上面部位、及び、上面部位に対応した底面及び長手両側面の部位に耐摩耗性部材を取り付けているので、レールやタイプレートとの摩擦摩耗やバラストとの摩擦摩耗の発生を効果的に抑止することができる。
耐摩耗性部材としては、適宜のものを採用可能であるが、クロロプレンゴム（ＣＲ）やスチレンブタジエンゴム（ＳＢＲ）などの一般的な合成ゴムを用いれば、省コスト化を図りつつ充分な耐摩耗性を発揮させることができる。
【００３０】
本発明において、耐摩耗性部材は種々の形状を採ることができる。例えば、板状の耐摩耗性部材を、まくら木の上面、底面及び長手両側面の各々に個別に接合する構成を採ることができる。
また、まくら木の上面から長手両側面及び底面にかけてを覆う方形筒形状の上面又は底面に位置する部位を切り離した一体化された耐摩耗性部材を用いることができる。この構成によれば、切り離し部分を押し広げつつ耐摩耗性部材をまくら木に容易に装着して接合することが可能である。
【００３１】
更に、左右に分離して形成された断面がコ字状の一対の耐摩耗性部材を用いる構成を採ることができる。この構成によれば、まくら木を敷設したままの状態でまくら木の幅方向から一対の耐摩耗性部材を容易に装着することが可能である。
【００３２】
また、耐摩耗性部材は、まくら木の上面において少なくともタイプレートがまくら木に当接する部位よりも広い面積を有する形状とすることにより、タイプレートによる摩擦摩耗を効果的に抑えることができる。
まくら木の底面及び長手両側面についても、少なくとも、タイプレートがまくら木の上面に固定される部位に対応した部位に耐摩耗性部材を設けることにより、バラストによる摩擦摩耗を効果的に防止することができる。
【００３３】
また、本発明において、耐摩耗性部材をまくら木の表面に取り付ける構造としては種々のものを採用可能である。例えば、まくら木の上面、底面及び長手両側面に耐摩耗性部材をそのまま貼付する取付構造を採ることができる。
また、まくら木の上面に耐摩耗性部材の厚さと略同一深さの帯状の溝を削設し、この溝に耐摩耗性部材を嵌入させて貼付することにより、まくら木の上面と耐摩耗性部材の表面とを同一面に形成する取付構造とすることができる。また、まくら木の底面や長手両側面にも同様の溝を設けて、底面や長手両側面に位置する耐摩耗性部材がまくら木の表面と同一面を形成する取付構造を採ることも可能である。
【００３４】
請求項８に記載の発明は、請求項７に記載のまくら木において、耐摩耗性部材は、まくら木の底面への当接部位が上面への当接部位に比べてまくら木の長手方向に長く形成され、まくら木の長手両側面への当接部位は上面側から底面側に向かうに連れて幅広となるように形成される構成とされている。
【００３５】
前記したように、列車の通過に伴う力は、全てレール又はタイプレートを介してまくら木へ伝達される。従って、まくら木の上面においてレール又はタイプレートの当接部位に印加される力は、まくら木の有する剛性に応じて底面側に近づくに連れて長手方向へ広がる部位で摩擦運動を生じさせる。このため、まくら木の底面に近い部位ほど、上面に比べて広い範囲で摩擦摩耗が生じて凹みや損傷が生じ易い。
本発明によれば、まくら木の底面側に向かうに連れて耐摩耗性部材を長手方向へ長く形成することにより、摩擦摩耗の生じ易い部位を覆って凹みや損傷の発生を防止することが可能となる。
【００３６】
請求項９に記載の発明は、請求項７又は８に記載のまくら木において、まくら木の底面及び／又は長手両側面に、前記耐摩耗性部材の側縁に沿って縁材を取り付けた構成とされている。
【００３７】
まくら木を道床に敷設すると、底面及び長手両側面の大部分はバラストに埋没する。このため、請求項７又は８に記載したまくら木では、まくら木に取り付けられた耐摩耗性部材の側縁にバラストが食い込んで剥がれるような不具合が生じ易い。特に、まくら木の底面及び長手両側面に耐摩耗性部材をその厚さ分だけ突出させて接合する取付構造では、耐摩耗性部材の側縁とまくら木の表面との間に段差が生じるために側縁に一層バラストが食い込み易くなる。
【００３８】
しかし、本発明によれば、耐摩耗性部材の側縁に沿って縁材を取り付けることにより、耐摩耗性部材の側縁が保護されてバラストの食い込みによる剥がれが防止され耐久性が向上する。
耐摩耗性部材として、前記した方形筒形状の底面に位置する部位を切り離した形状や、左右に分離して形成された断面がコ字状の形状を採用する場合は、まくら木の底面において耐摩耗性部材が切り離されている部分の側縁に沿って縁材を設けることもできる。この構成によれば、耐摩耗性部材の側縁が縁材で保護されてバラストの食い込みによる剥がれを防止可能である。
縁材には、例えば、適宜の厚さの板材を用いることができる。
【００３９】
請求項１０に記載の発明は、請求項９に記載のまくら木において、縁材は、当該縁材のまくら木表面からの突出長が前記耐摩耗性部材のまくら木表面からの突出長以上であって略等しいか、又は、当該縁材のまくら木表面からの突出長が軌道上に敷設されるバラストの平均粒径と略等しい構成とされている。
【００４０】
ここで、縁材に、耐摩耗性部材の耐久性を向上させる機能だけを要求する場合は、縁材のまくら木表面からの突出長が耐摩耗性部材のまくら木表面からの突出長以上であって略等しい形状とするのが良い。これにより、耐摩耗性部材の表面と縁材の表面とが略同一面を形成し、耐摩耗性部材の側縁が縁材に保護されてバラストの食い込みが防止される。この構成では、縁材として、耐摩耗性部材と同一厚さを有する板材を採用することができる。
【００４１】
一方、縁材に、耐摩耗性部材の耐久性を向上させる機能に加えて、まくら木の位置ずれを防止する機能を要求する場合は、縁材を、まくら木表面からの突出長が軌道上に敷設されるバラストの平均粒径と略等しい突条形状とするのが良い。この構成によれば、耐摩耗性部材の側縁が縁材で保護されるうえに、請求項５に記載したまくら木と同様の理由により、突条形状を呈する縁材によってまくら木の位置ずれを効果的に抑止可能である。この構成では、縁材としてバラストの平均粒径と略等しい高さを有する角材などを用いることが可能である。
【００４２】
請求項１１に記載の発明は、請求項７乃至１０のいずれか１項に記載のまくら木において、まくら木の底面における耐摩耗性部材が取り付けられていない部位に、まくら木の長手方向及び／又はまくら木の幅方向へ延びる突条を形成した構成とされている。
【００４３】
本発明によれば、耐摩耗性部材によってまくら木の摩擦摩耗が抑えられて耐久性が向上するうえに、前記請求項１，３に記載したまくら木と同様の理由により、まくら木の道床横方向あるいは道床縦方向への位置ずれを効果的に抑止することが可能となる。
また、本発明において、耐摩耗性部材としてまくら木の底面の部位で切り離された形状のものを採用する場合は、当該底面の切り離し部分に長手方向に沿って突条を形成しても良い。この構成によれば、まくら木の道床縦方向への位置ずれを抑止すると共に、耐摩耗性部材の側縁が保護されて耐久性が向上する。
【００４４】
請求項１２に記載の発明は、請求項７乃至１０のいずれか１項に記載のまくら木において、まくら木の底面における耐摩耗性部材が取り付けられている部位に、まくら木の長手方向及び／又はまくら木の幅方向へ延びる突条を形成した構成とされている。
【００４５】
本発明によれば、耐摩耗性部材によってまくら木の摩耗が抑えられて耐久性が向上する上に、前記請求項１及び３に記載したまくら木と同様の理由により、まくら木の道床横方向および道床縦方向への位置ずれを軌道部の位置近傍を中心に効果的に抑止することができる。
【００４６】
また、請求項１３に記載の発明は、請求項１１又は１２に記載のまくら木において、突条は、当該突条のまくら木表面からの突出長が軌道上に敷設されるバラストの平均粒径と略等しい構成とされている。
本発明によれば、まくら木の摩擦摩耗が抑えられて耐久性が向上すると共に、前記請求項６に記載したまくら木と同様の理由により、まくら木の道床横方向及び／又は道床縦方向への位置ずれを効果的に防止することが可能となる。
【００４７】
ここで、請求項１乃至１３に記載のまくら木において、まくら木をコンクリートで製することが可能である。ここに、コンクリート製のまくら木とは、予めストレスを加えた鋼材をコンクリートに内蔵させて一体的に固着させたＰＣ（Ｐｒｅｓｔｒｅｓｓｅｄ−Ｃｏｎｃｒｅｔｅ）製のものを指す。製造に際しては、予め突条や縁材を形成した成形型にコンクリートを流し込んで硬化させることにより、突条や縁材を一体的に形成したコンクリート性のまくら木とすることができる。
ＰＣ製まくら木によれば、耐摩耗性、低価格の長所を生かしつつ道床横方向及び／又は道床縦方向への位置ずれを抑止したまくら木を構成することができる。
【００４８】
また、請求項１乃至１３に記載のまくら木において、まくら木や突条、縁材は、長繊維強化硬質合成樹脂発泡体を素材とする合成木材を用いて製することができる。特に、紫外線劣化を受けないガラス繊維強化硬質樹脂発泡体の板材で成されたまくら木であれば、耐久性、加工性が向上すると共に軽量化を図ることができる。
まくら木にかかる応力は、主としてレールを支点とする曲げモーメントに起因するものであり、まくら木の長手方向への高い曲げ剛性（ＥＩ）が要求される。そこで、まくら木や突条、縁材を合成木材で成する場合、合成木材に含まれる繊維方向が各部材の長手方向となるようにするのが良い。則ち、合成木材の繊維方向を各部材の長手方向へ合わせたものや、或いは、繊維方向の異なる合成木材を積層した部材とすることにより、高い曲げ剛性を得ることができる。
【００４９】
ガラス長繊維強化硬質合成樹脂発泡体は、ガラス繊維、炭素繊維、金属繊維、セラミック繊維等の無機質繊維、芳香族ポリアミド繊維等の合成繊維や天然繊維等の有機質繊維等を補強材として含み、マトリクスとして、ウレタン樹脂、エポキシ樹脂、ビニルエステル樹脂、不飽和ポリエステル樹脂、フェノール樹脂などの熱硬化樹脂等の発泡体が例示される。また、圧縮強度の向上や低コスト化を図るために、発泡樹脂中に炭酸カルシウム、石膏、タルク、水酸化アルミニウム、クレー等の無機充填材、シラスバルーン、パーライト、ガラスバルーン等の軽量骨材などの各種添加材が添加されても良い。これらの中でも、好適な材料としては硬質ウレタン樹脂をガラス長繊維で補強した発泡体であり、例えば、商品名「エスロンネオランバーＦＦＵ」（積水化学工業株式会社製）が挙げられる。
【００５０】
【発明の実施の形態】
以下に、図面を参照して本発明の好適な実施形態を説明する。
図１（ａ）は第１実施形態のまくら木１を示す斜視図、図１（ｂ）は（ａ）の分解斜視図である。
まくら木１は、通常サイズのまくら木本体２０の底面２０ｂの幅方向中央部に、長手方向へ向けて全長に渡って角材２１を接合して突条２１を形成したものである。角材２１は、道床に敷設されるバラストの平均粒径に近い高さとされ、本実施形態では、角材２１の高さを５０ｍｍとしている。
本実施形態では、まくら木１を構成するまくら木本体２０及び角材２１に、ガラス長繊維強化硬質ウレタン樹脂発泡体を素材とする合成木材を用いている。
【００５１】
このまくら木１によれば、図１（ａ）の様に、まくら木１をＡ方向（レール方向：道床縦方向）から見たときの高さは、まくら木本体２０の高さに突条（角材）２１の高さを加えたものとなり、突条２１を設けない場合に比べて道床縦方向におけるバラスト接触面積が増加する。これにより、まくら木１に道床縦方向へ向けて加わる力に抗するバラストの抗力が増大して道床縦方向への位置ずれが抑制される。
【００５２】
また、本実施形態のまくら木１では、突条２１の突出長がバラストの平均粒径と略等しいので、まくら木の底面２０ｂに当接するバラストの突出長が突条２１の突出長と略等しくなる。これにより、突条の先端部にバラストの中央部が当接することが少なく、まくら木に道床縦方向へ向けて力が加わった際に、突条２１の先端部がバラストを乗り越えてずれるような不具合が生じ難くなり、突条２１はバラストから安定した抗力を受けて位置ずれを防止することが可能となる。
【００５３】
尚、本実施形態では、まくら木本体２０に角材２１を接合することにより突条２１を形成しているが、例えば、通常サイズよりも高い合成木材製角柱材の底面の長手両側縁近傍を長手方向全長に渡って切削してまくら木と一体化された長手方向へ延びる突条を形成することも可能である。
【００５４】
また、本実施形態のまくら木１は、通常サイズのまくら木本体２０の底面２０ｂに角柱材を取り付けた構造であり、まくら木の断面積が底部で増加すると共に、長手方向全長に渡って角柱材が取り付けられることによりバラストとの接触面積が増加して道床横抵抗力が増大し、結果的に道床横方向への位置ずれも抑制される。
【００５５】
図２（ａ）は第２実施形態のまくら木２を示す斜視図、図２（ｂ）は（ａ）の分解斜視図である。
まくら木２は、まくら木本体２０の底面２０ｂに４本の角材２２を接合して突条２２を形成したものである。角材２２は、まくら木本体２０の長手端部から長手方向に向けてタイプレートＴの固定位置を超える部位に至る長さを有しており、この角材２２をまくら木本体２０の底面２０ｂに長手両端部から長手両側縁に沿って４本接合している。
【００５６】
このまくら木２によれば、図２（ａ）の様に、タイプレートＴの固定される部位の近傍においてＡ方向から見たときの高さは、まくら木本体２０の高さに突条（角材）２２の高さを加えたものとなり、突条２２を設けない場合に比べてバラスト接触面積が増加する。これにより、まくら木２に道床縦方向へ向けて加わる力に抗するバラストの抗力が増大して道床縦方向への位置ずれが抑制される。
【００５７】
また、本実施形態のまくら木２は、レールから伝達される力が加わるタイプレートＴとバラストからの抗力が加わる突条２２とを近接配置した形状を採用しているので、まくら木２に加わる力や抗力による撓みの発生を低減して撓みに伴う摩擦の発生を抑えつつ道床縦方向への位置ずれを効果的に抑制可能である。
また、まくら木２を道床に敷設すると、底面２０ｂに対向して形成される突条２２，２２の隙間にバラストが嵌入して突条２２に対して大きな摩擦力を発生し、道床縦方向への位置ずれの抑制効果が増大する。
【００５８】
また、本実施形態のまくら木２は、図１の場合と同様に、まくら木の断面積が底部で増加すると共に、長手方向のバラストとの接触面積が増加して道床横抵抗力が向上し、結果的に道床横方向への位置ずれも抑制される。
【００５９】
図３（ａ）は第３実施形態のまくら木３を示す斜視図、図３（ｂ）は（ａ）の分解斜視図である。まくら木３は、まくら木本体２０の底面２０ｂに角材２３，２４を接合して突条２３，２４を形成したものである。
【００６０】
角材２３は、まくら木本体２０の長手端部から長手中央に向けてタイプレートＴの固定位置を超える部位に至る長さを有しており、この角材２３をまくら木本体２０の底面２０ｂの長手両端部から長手両側縁に沿って４本接合している。また、角材２４は、対向する角材２３，２３の長手両端部間を掛け渡すようにしてまくら木本体２０の底面２０ｂに幅方向へ向けて接合されている。則ち、まくら木３は、まくら木本体２０の底面２０ｂに、長手方向へ延びる突条２３と幅方向へ延びる突条２４を形成している。
【００６１】
このまくら木３によれば、図３（ａ）の様に、まくら木３をＢ方向（道床横方向：レールと直交する方向）から見たときのバラスト接触面積が突条２４を設けない場合に比べて増加する。これにより、まくら木３に道床横方向へ向けて加わる力に抗するバラストの抗力が増大して道床横方向への位置ずれが抑制され、しかも、突条２３によって、前記第２実施形態のまくら木２と同様に道床縦方向の位置ずれが抑制される。
【００６２】
また、まくら木３を道床に敷設すると、底面２０ｂに突条２３，２４によって形成される方形枠の内部にバラストが嵌入して突条２３，２４に対する摩擦力が強大となり、道床縦方向及び道床横方向への位置ずれの抑制効果が増大する。
尚、突条２３，２４により形成される方形枠の内部のまくら木底面に耐摩耗性材を貼りつけると、剥がれにくく、耐久性を向上させることができる。
【００６３】
図４（ａ）は第４実施形態のまくら木４を示す斜視図、図４（ｂ）は（ａ）の分解斜視図である。まくら木４は、まくら木本体２０に、その底面２０ｂから長手両側面２０ｃにかけて延びるコ字状の位置ずれ防止部材２５を接合することにより、突条２５ａ，２５ｂを形成したものである。
【００６４】
位置ずれ防止部材２５は、図４（ｂ）の様に、まくら木本体２０の底面２０ｂに沿って幅方向に延びる水平部２５ａと、当該水平部２５ａの両端からまくら木本体２０の長手両側面２０ｃに沿って上方に延びる垂直部２５ｂを備えて一体化して製されており、水平部２５ａ及び垂直部２５ｂの断面形状はいずれも方形である。位置ずれ防止部材２５は、タイプレートＴの固定部位の両端部近傍に各々２個ずつ固定されている。
【００６５】
このまくら木４によれば、図４（ａ）の様に、まくら木４をＢ方向（道床横方向）から見たときのバラスト接触面積が、位置ずれ防止部材２５を設けない場合に比べて増加する。これにより、まくら木４に道床横方向へ向けて加わる力に抗するバラストの抗力が増大して道床横方向への位置ずれが抑制される。
尚、本実施例では、一体化して形成された位置ずれ防止部材２５を用いたが、例えば、角材を接合して同形状の位置ずれ防止部材２５を形成することも可能である。
【００６６】
図５（ａ）は第５実施形態のまくら木５を示す斜視図、図５（ｂ）は（ａ）のまくら木５を底面側から見た分解斜視図である。
本実施形態のまくら木５は、前記第４実施形態のまくら木４に長手方向へ延びる突条を追加した構成である。
則ち、まくら木５は、前記まくら木４において、タイプレートＴの固定部位に隣接して配置される道床横方向の位置ずれ防止部材２５の水平部２５ａ同士の間に角材２６を接合して突条２６を形成したものである。角材２６は、道床横方向の位置ずれ防止部材２５の水平部２５ａの中央部同士を繋ぐように設けられ、これによって、突条２６はまくら木本体２０の底面２０ｂの幅方向中央部に長手方向へ向けて形成される。
【００６７】
このまくら木５によれば、図５（ａ）の様に、まくら木５をＡ方向（道床縦方向）から見たときのバラスト接触面積が、突条２６を設けない場合に比べて増加する。これにより、前記第４実施形態のまくら木４に示した道床横方向への位置ずれ防止効果に加えて、まくら木５に道床縦方向へ向けて加わる力に抗するバラストの抗力が増大して道床縦方向への位置ずれが抑制される。則ち、まくら木５は、道床横方向と道床縦方向の両方向の位置ずれが抑制される。
【００６８】
図６（ａ）は第６実施形態のまくら木６を示す斜視図、図６（ｂ）は（ａ）の分解斜視図である。
前記第５実施形態のまくら木５では、タイプレートＴの固定部位に隣接配置される位置ずれ防止部材２５同士の間に突条２６を形成した。
これに対して、本実施形態のまくら木６は、タイプレートＴの固定部位に隣接して配置される位置ずれ防止部材２５同士の間を除く部位に、まくら木本体２０の底面２０ｂの幅方向中央部に長手方向へ向けて角材２７，２８を配して突条２７，２８を形成したものである。
【００６９】
則ち、角材２７は、まくら木本体２０の長手両端部側に位置する道床横方向の位置ずれ防止部材２５とまくら木本体２０の長手端部との間に接合されて突条２７を形成する。また、角材２８は、まくら木本体２０の長手内方に位置する道床横方向の位置ずれ防止部材２５同士の間に接合されて突条２８を形成している。
【００７０】
このまくら木６によれば、突条２７，２８が前記第５実施形態のまくら木５の突条２６に比べて長くなり、図６（ａ）の様に、まくら木６にＡ方向（道床縦方向）へ向けて加わる力に抗するバラストの抗力が一層増大して道床縦方向への位置ずれを効果的に抑制することが可能である。則ち、まくら木６は、道床横方向と道床縦方向の両方向の位置ずれが抑制される。
【００７１】
次に、図７は第７実施形態のまくら木７を示す斜視図である。
本実施形態のまくら木７は、まくら木本体２０のタイプレートＴの固定部位近傍に、表面に沿って帯状に耐摩耗性部材３０を取り付けたものである。
則ち、まくら木本体２０のタイプレート固定部位２０ｄと、当該固定部位２０ｄに対応する底面２０ｂ及び長手両側面２０ｃの部位に耐摩耗性部材３０を取り付けたものである。
【００７２】
耐摩耗性部材３０は、上面部３０ａ、底面部３０ｂ及び側面部３０ｃを備えて形成され、これらの各部はまくら木本体２０の上面２０ａ、底面２０ｂ及び長手両側面２０ｃに接合される。
耐摩耗性部材３０の上面部３０ａは、タイプレート固定部位２０ｄよりも広い面積を有しており、タイプレートＴをまくら木本体２０に固定する際は、タイプレートＴとまくら木本体２０との間に耐摩耗性部材３０が介在して取り付けられる。また、耐摩耗性部材３０の底面部３０ｂ及び側面部３０ｃのまくら木本体２０の長手方向へ向かう長さは上面部３０ａと同一である。
【００７３】
本実施形態のまくら木７を道床に敷設すると、まくら木本体２０の底面２０ｂ及び長手両側面２０ｃの下部側がバラストに埋没する。しかし、耐摩耗性部材３０が取り付けられているので、タイプレートＴとまくら木本体２０のタイプレート固定部位２０ｄとの間に生じる摩擦、及び、まくら木本体２０の底面２０ｂや長手両側面２０ｃとバラストとの間に生じる摩擦に対して耐摩耗性を発現して、まくら木本体２０の表面に凹みや損傷が生じることが防止される。
【００７４】
耐摩耗性部材３０としては、弾性を有する合成ゴム材や合成樹脂材を用いることができ、例えば、クロロプレンゴム（ＣＲ）、スチレンブタジエンゴム（ＳＢＲ）、ウレタンゴム、イソシアネート樹脂などを採用することができる。中でも、一般的に使用されるクロロプレンゴムやスチレンブタジエンゴムは安価であり、充分な耐摩耗性を発揮するので好適である。
【００７５】
ところで、本実施形態のまくら木７において、まくら木本体２０に取り付ける耐摩耗性部材３０は種々の形状を採ることができる。
例えば、図８（ａ）の様に、耐摩耗性部材３０を、上面部材３０ａ、底面部材３０ｂ及び側面部材３０ｃ，３０ｃの分離した４枚の板材で形成できる。
そして、これらの部材をまくら木本体２０の上面２０ｃ、底面２０ｂ及び長手両側面２０ｃ，２０ｃに樹脂接着剤などで接合して、まくら木本体２０の表面に耐摩耗性部材３０を取り付ける構成を採ることができる。
この構成では、図８（ｂ）の様に、耐摩耗性部材３０がその厚さだけまくら木本体２０の表面から突出した状態で接合される。
【００７６】
また、図９（ａ）の様に、耐摩耗性部材３０を、まくら木本体２０の表面に沿って平面部３０ａ、側面部３０ｃ及び底面部３０ｂを有する方形筒形状に形成された部材の底面部３０ｂに、長手方向に向けて切り離し部３０ｄを設けた一体化された形状とすることも可能である。
【００７７】
この耐摩耗性部材３０は、図９（ａ）の様に、側面部３０ｃ，３０ｃを僅かに外方へ押し広げつつまくら木本体２０の長手端部から挿入して装着したり、あるいは、図９（ｂ）の様に、側面部３０ｃ，３０ｃを外方へ押し広げつつまくら木本体２０に上面２０ａから被せて装着することができる。
また、この耐摩耗性部材３０は、図９（ｃ）の様に、切り離し部３０ｄがまくら木本体２０の底面２０ｂに位置するように取り付けたり、逆に、図９（ｄ）の様に、切り離し部３０ｄがまくら木本体２０の上面２０ａに位置するように取り付けることが可能である。
【００７８】
また、耐摩耗性部材３０の別の形状として、図１０（ａ）の様に、左右に分離された断面がコ字状の一対の溝型部材３１，３１を組み合わせた構成を採ることができる。則ち、溝型部材３１は、まくら木本体２０の上面２０ａ、長手両側面２０ｃ及び底面２０ｂに沿うように、平面部３０ａ、側面部３０ｃ及び底面部３０ｂを備えて断面がコ字状に形成された部材である。
この耐摩耗性部材３０は、まくら木本体２０の長手両側面２０ｃを挟むようにして一対の溝型部材３１を両側から被せて装着することができ、まくら木７を敷設したままの状態における耐摩耗性部材３０の取り付けが可能となる。
この耐摩耗性部材３０をまくら木本体２０に取り付けると、上面２０ａ及び底面２０ｂに長手方向に向けて切り離し部３１ｄが形成される。
【００７９】
ここで、前記図８〜図１０に示した耐摩耗性部材３０は、いずれも素材を異形押出により腑形成形して製するのが良い。耐摩耗性部材３０をこの成形法を用いて製することにより、形状が安定すると共に、まくら木本体２０へ接合した場合に剥がれが生じにくい。
【００８０】
一方、耐摩耗性部材３０をまくら木本体２０の表面に取り付ける際の取付構造についても種々のものを採用することができる。
例えば、図１１（ａ），（ｂ）の様に、まくら木本体２０の上面２０ａ、底面２０ｂ及び長手両側面２０ｃに、耐摩耗性部材３０の上面部３０ａ、底面部３０ｂ及び側面部３０ｃをその厚さだけ突出させて接合する構成を採用できる。
【００８１】
また、図１１（ｃ）の様に、予め、まくら木本体２０の上面２０ａに、耐摩耗性部材３０の厚さと略等しい深さの帯状の溝部２１を幅方向全長に渡って形成し、耐摩耗性部材３０の上面部３０ａを溝部２１に嵌入させて装着する構成を採ることができる。この構成によれば、図１１（ｄ）の様に、耐摩耗性部材３０の上面部３０ａとまくら木本体２０の上面部２０ａが略同一面となり、まくら木本体２０の他の面では、耐摩耗性部材３０がその厚さだけ突出する。
【００８２】
また、図１１（ｅ）の様に、まくら木本体２０の上面２０ａの溝部２１に対向させて、底面２０ｂにも、耐摩耗性部材３０の厚さと略等しい深さの帯状の溝部２２を幅方向全長に渡って形成し、耐摩耗性部材３０の上面部３０ａ及び底面部３０ｂを各々溝部２１，２２に嵌入させて装着する構成を採ることができる。この構成によれば、図１１（ｆ）の様に、耐摩耗性部材３０の上面部３０ａ及び底面部３０ｂは各々まくら木本体２０の上面２０ａ及び底面２０ｂと略同一面となり、まくら木本体２０の長手両側面２０ｃでは、耐摩耗性部材３０がその厚さだけ突出する。
【００８３】
更に、図１１（ｇ）の様に、まくら木本体２０の上面２０ａ及び底面２０ｂに設けた溝部２１，２２に対応させて、長手両側面２０ｃにも、耐摩耗性部材３０の厚さと略等しい深さの帯状の溝部２３，２３を高さ方向全長に渡って形成し、耐摩耗性部材３０の上面部３０ａ、底面部３０ｂ及び側面部３０ｃの全てを各々溝部２１，２２，２３に嵌入させて装着する構成を採ることができる。この構成によれば、図１１（ｈ）の様に、まくら木本体２０の表面と耐摩耗性部材３０の表面が全て略同一面となる状態で取り付けられる。
【００８４】
この図１１（ａ）〜（ｈ）に示した耐摩耗性部材３０の取付構造において、まくら木本体２０の表面と耐摩耗性部材３０の表面とが略同一面を形成するものでは、まくら木７の敷設時に、バラストが耐摩耗性部材３０の側縁に食い込み難く、剥がれが防止されて耐久性を向上させることができる。
尚、本実施形態のまくら木７は、前記図８〜図１０に示した耐摩耗性部材３０の形状と前記図１１に示した耐摩耗性部材３０の取付構造とを適宜に組み合わせて形成することが可能である。
【００８５】
図１２は第８実施形態のまくら木８を示す斜視図、図１３はそのまくら木８の耐摩耗性部材の取付状態を示す分解斜視図、斜視図及び側面図である。本実施形態のまくら木８は、前記第７実施形態のまくら木７の構成を一部変更したものである。
【００８６】
則ち、まくら木８は、図１３（ａ）の様に、まくら木本体２０の上面２０ａ、底面２０ｂ及び長手両側面２０ｃに耐摩耗性部材３０を形成する上面部材３２ａ、底面部材３２ｂ及び側面部材３２ｃを各々接合したもので、図１３（ｂ）の様に、まくら木本体２０の表面から耐摩耗性部材３２はその厚さだけ突出して取り付けられる。
【００８７】
まくら木８に採用する耐摩耗性部材３２は、図１３（ａ）の様に、まくら木本体２０の上面２０ａに当接する上面部材３２ａについては、第７実施形態に採用した耐摩耗性部材３０と同一形状である。
一方、まくら木本体２０の底面２０ｂへ当接する底面部材３２ｂは、上面部材３２ａに比べてまくら木本体２０の長手方向に長く形成され、まくら木本体２０の長手両側面へ当接する側面部材３２ｃは上面側から底面側に向かうに連れて幅広となるように形成されている。
【００８８】
ここで、本実施形態では、図１３（ｃ）の様に、耐摩耗性部材３２の側面部材３２ｃの形状を台形形状とし、この側面部材３０ｃの底辺と傾斜辺が成す角度θを略４５度に形成している。これにより、タイプレートＴを介してまくら木本体２０の上面２０ａに加わる力に起因して、まくら木本体２０の有する剛性に応じて底面２０ｂに近づくに連れて長手方向へ摩擦の生じる範囲が広がっても、摩擦摩耗に伴う損傷を効果的に抑制することが可能となる。
【００８９】
尚、角度θが４５度よりも小さい場合は側面部材３０ｃ及び底面部材３０ｂの面積が低下して摩擦の生じ易い部位を覆うことができない。また、角度θが４５度よりも大きい場合は、摩擦の生じ易い部位を充分に覆うことができるが、側面部材３０ｃ及び底面部材３０ｂの面積が増加してコストが増大する。
側面部材３０ｃの底辺と傾斜辺で成す角度θは略４５度が最適である。
【００９０】
また、本実施形態ではまくら木本体２０の各表面に耐摩耗性部材３２を形成する上面部材３２ａ、底面部材３２ｂ及び側面部材３２ｃを接合する構成を採用したが、例えば、前記図９に示した様に、一体化して形成された耐摩耗性部材を用いることも可能であり、前記図１０に示した様に、分離形成された一対の溝型部材を組み合わせた耐摩耗性部材を用いることも可能である。
また、耐摩耗性部材３２のまくら木本体２０への取付構造についても、前記図１１に示した構造を適宜採用可能である。
【００９１】
図１４（ａ）は第９実施形態のまくら木９を示す斜視図、（ｂ）はその部分分解斜視図、（ｃ）は（ａ）のＡ−Ａ矢視断面図、（ｄ）は（ｃ）の円内拡大図である。
本実施形態のまくら木９は、前記第７実施形態のまくら木７において、まくら木本体２０の底面２０ｂ及び長手両側面２０ｃに、耐摩耗性部材３０の側縁に沿って縁材４０，４１を接合したものである。
耐摩耗性部材３０は、図１４（ｂ）の様に、まくら木本体２０の表面に上面部材３０ａ、底面部材３０ｂ及び側面部材３０ｃを各々接合して形成され（図８参照）、まくら木本体２０の表面から耐摩耗性部材３０がその厚さだけ突出する取付構造（図１１（ｂ）参照）を採用している。
【００９２】
縁材４０は、図１４（ｂ）の様に、耐摩耗性部材３０よりも僅かに厚く、まくら木本体２０の幅と略等しい長さを有する平板材であり、その長手側縁を耐摩耗性部材３０の底面部材３０ｂの側縁と突き合わせるようにしてまくら木本体２０の底面２０ｂに接合されている。この縁材４０は、耐摩耗性部材３０の底面部材３０ｂの対向する２カ所の側縁に各々接合されている。
【００９３】
また、縁材４１は、縁材４０と同一の厚さを有し、まくら木本体２０の高さと略等しい長さを有する平板材であり、その長手側縁を耐摩耗性部材３０の側面部材３０ｃの側縁と突き合わせるようにしてまくら木本体２０の長手両側面２０ｃに接合されている。この縁材４１は、耐摩耗性部材３０の側面部材３０ｃの対向する２カ所の側縁に各々接合されている。
【００９４】
このように、縁材４０，４１をまくら木本体２０の底面２０ｂ及び長手両側面２０ｃに接合すると、図１４（ｃ），（ｄ）の様に、耐摩耗性部材３０の底面部材３０ｂ及び側面部材３０ｃの表面よりも縁材４０，４１の表面が僅かに突出した状態で取り付けられる。
従って、まくら木９を道床に敷設すると、耐摩耗性部材３０ｂ，３０ｃの側縁が縁材４０，４１で完全に保護されてバラストの食い込みが防止され、耐摩耗性部材３０の剥がれを防止し耐久性を向上させることが可能となる。
【００９５】
図１５（ａ）は第１０実施形態のまくら木１０を示す斜視図、（ｂ）は（ａ）の部分分解斜視図、（ｃ）は（ａ）のＡ−Ａ矢視断面図である。
本実施形態のまくら木１０は、前記第９実施形態で示したまくら木９の縁材４０，４１の形状を変更したものである。
【００９６】
まくら木１０に採用する縁材２５は、前記第４実施形態のまくら木４（図４参照）に採用した位置ずれ防止部材２５と同様の形状である。則ち、縁材２５は、まくら木本体２０の底面２０ｂに沿って幅方向に延びる水平部２５ａと、当該水平部２５ａの両端からまくら木本体２０の長手両側面２０ｃに沿って上方に延びる垂直部２５ｂを備えて一体化して製されており、水平部２５ａ及び垂直部２５ｂの断面形状はいずれも方形である。
【００９７】
そして、２個の縁材２５を、その側縁を耐摩耗性部材３０の底面部材３０ｂ及び側面部材３０ｃの側縁に沿わせるようにまくら木本体２０の底面２０ｂ側から挿入して接合固定している。このように縁材２５を取り付けると、図１５（ｃ）の様に、耐摩耗性部材３０の底面部材３０ｂ及び側面部材３０ｃの表面よりも縁材２５の水平部２５ａ及び垂直部２５ｂが突出した状態で取り付けられる。
【００９８】
従って、まくら木１０を道床に敷設すると、耐摩耗性部材３０ｂ，３０ｃの側縁が縁材２５で保護されてバラストの食い込みが防止され、耐摩耗性部材３０の剥がれを防止し耐久性を向上させることが可能となる。
また、縁材２５が突条を形成して、前記第４実施形態のまくら木４（図４参照）に採用した位置ずれ防止部材２５と同様の機能を発現し、まくら木１０の道床横方向への位置ずれを効果的に抑制することが可能となる。
【００９９】
図１６（ａ）は第１１実施形態のまくら木１１を示す斜視図、（ｂ），（ｃ）は（ａ）の部分分解斜視図、（ｄ）は（ａ）のＡ−Ａ矢視断面図である。
本実施形態のまくら木１１は、前記第１０実施形態のまくら木１０において、耐摩耗性部材３０の形状及び取付構造を変更したものである。
【０１００】
則ち、耐摩耗性部材３０は、図１６（ｂ）の様に、まくら木本体２０の表面に沿うように方形筒形状に成形された底面部３０ｂに長手方向に切り離し部３０ｄを設けて一体化された形状を有する（図９参照）。
また、まくら木本体２０の上面２０ａに溝部２１を形成し、耐摩耗性部材３０の上面部３０ａを溝部２１に嵌入させて装着する取付構造を採用している（図１１（ｃ），（ｄ）参照）。
【０１０１】
そして、まくら木１１は、図１６（ｂ）の様に、まくら木本体２０に耐摩耗性部材３０を装着して接合し、この後に、図１６（ｃ）の様に縁材２５を耐摩耗性部材３０の側縁に沿って取付固定して製される。
このまくら木１１では、図１６（ｄ）の様に、耐摩耗性部材３０の上面部３０ａはまくら木本体２０の上面２０ａと同一面となり、耐摩耗性部材３０の切り離し部３０ｄはまくら木本体２０の底面２０ｂに位置する。
【０１０２】
従って、本実施形態のまくら木１１によれば、前記第１０実施形態のまくら木１０と同様に、まくら木１１を道床に敷設すると、耐摩耗性部材３０の底面部３０ｂ及び側面部３０ｃの側縁が縁材２５で保護されてバラストの食い込みが防止されると共に、縁材２５が突条を形成して、まくら木１１の道床横方向への位置ずれを効果的に抑制する。
【０１０３】
尚、本実施形態のまくら木１１において、耐摩耗性部材３０の切り離し部３０ｄが位置するまくら木本体２０の底面２０ｂに、板状の縁材を接合する構成としても良い。この構成によれば、耐摩耗性部材３０の切り離し部３０ｄが縁材によってバラストから保護されて剥がれが防止される。
【０１０４】
図１７（ａ）は第１２実施形態のまくら木１２を示す斜視図、（ｂ），（ｃ）はまくら木１２の組み立て手順を底面側から見た分解斜視図、（ｄ）はまくら木１２を底面側から見た斜視図である。
本実施形態のまくら木１２は、前記第１１実施形態のまくら木１１において、耐摩耗性部材３０の取付構造を変更すると共に、耐摩耗性部材３０の切り離し部３０ｄの部位に突条２６を形成したものである。
【０１０５】
則ち、前記第１１実施形態のまくら木１１では、まくら木本体２０の上面２０ａに溝部２１を設けた取付構造であったが、本実施形態のまくら木１２では、図１７（ｂ）の様に、まくら木本体２０に溝部を設けず、一体的に製された耐摩耗性部材３０をまくら木本体２０に装着する構成である。
また、耐摩耗性部材３０の側縁に沿って取り付けられる縁材２５，２５の水平部２５ａ同士の間に角材２６を配して突条２６を形成しており、この角材２６は、耐摩耗性部材３０の切り離し部３０ｄの部位に位置する。
【０１０６】
本実施形態のまくら木１２によれば、突条２６は、まくら木本体２０の底面２０ｂの幅方向中央部に長手方向へ向けて形成されるので、前記第１１実施形態のまくら木１１の効果に加えて、まくら木１２の道床縦方向への位置ずれを抑制することができる。
また、角材２６が耐摩耗性部材３０の切り離し部３０ｄの部位に取り付けられるので、切り離し部３０ｄの側縁がバラストから保護され、耐摩耗性部材３０の剥がれが防止されて耐久性が向上する。
【０１０７】
図１８（ａ）は第１３実施形態のまくら木１３を示す斜視図、（ｂ）はまくら木１３を底面側から見た分解斜視図、（ｃ）はまくら木１３を底面側から見た斜視図である。
本実施形態のまくら木１３は、前記第１２実施形態のまくら木１２において、まくら木本体２０の長手方向へ延びる突条の位置を変更したものである。
則ち、前記第１２実施形態のまくら木１２では、耐摩耗性部材３０の側縁に隣接配置される縁材２５同士の間に突条２６を形成したものであった。
これに対して、本実施形態のまくら木６は、隣接配置される縁材２５同士の間を除く部位に、まくら木本体２０の長手方向へ向けて角材２７，２８を配して突条２７，２８を形成したものである。
【０１０８】
則ち、角材２７は、まくら木本体２０の長手外方に位置する縁材２５とまくら木本体２０の長手端部との間に接合されて突条２７を形成し、角材２８は、まくら木本体２０の長手内方に位置する縁材２５同士の間に接合されて突条２８を形成している。
【０１０９】
本実施形態のまくら木１３によれば、突条２７，２８の長さが、前記第１２実施形態のまくら木１２の突条２６に比べて長いので、まくら木１３の道床縦方向への位置ずれを一層抑制することが可能となる。
尚、本実施形態では、耐摩耗性部材３０の切り離し部３０ｄに角材を設けていないが、前記第１２実施形態と同様に、当該切り離し部３０ｄに角材２６を接合することにより、耐摩耗性部材３０の耐久性及びまくら木１３の道床縦方向への位置ずれ抑制効果を一層向上させることが可能である。
【０１１０】
また、図１８（ｄ）は、まくら木１３に、突条２８’を追加して形成したまくら木１３’を底面側から見た斜視図である。則ち、まくら木１３’は、耐摩耗性部材３０の側縁に隣接して配置される縁材２５同士の間において、まくら木本体２０の底面２０ｂの幅方向中央部に長手方向へ向けて角材２８’を接合して突条２８’を形成したものである。
このまくら木１３’によれば、突条２７，２８’，２８がまくら木本体２０の長手方向へ向けて全長に渡って設けられた構造となり、図１８（ｃ）に示したまくら木１３に比べて、耐摩耗性部材３０の耐久性向上及び道床縦方向への位置ずれ防止効果を一層向上させることができる。
【０１１１】
図１９（ａ）は第１４実施形態のまくら木１４を示す斜視図、（ｂ）はまくら木１４を底面側から見た分解斜視図、（ｃ）はまくら木１４を底面側から見た斜視図である。
本実施形態のまくら木１４は、前記第１０実施形態のまくら木１０において、まくら木本体２０の底面２０ｂの耐摩耗性部材３０が取り付けられていない部位に、まくら木本体２０の幅方向へ向けて複数の角材２９を接合して複数の突条２９を形成したものである。本実施形態では、角材２９は縁材２５の水平部２５ａ及び垂直部２５ｂよりも小さい断面積を有するものを用いている。
【０１１２】
角材２９は、まくら木本体２０の長手両端部近傍であって縁材２５の外方に各々１本ずつ接合され、まくら木本体２０長手中央部近傍であって隣接する縁材２５同士の間に間隔をおいて２本接合している。
本実施形態のまくら木１４によれば、前記まくら木１０と同様に耐摩耗性部材３０の耐久性が向上すると共に、突条２９によってまくら木１４の道床横方向への位置ずれを一層抑制することが可能となる。
【０１１３】
以上、本発明の実施形態を説明したが、前記第２〜第６実施形態のまくら木に採用した突条２２〜２８、及び、前記第１０〜第１４実施形態のまくら木に採用した縁材２５及び突条２６〜２８については、前記第１実施形態のまくら木１と同様に、まくら木本体２０の表面からの突出長が、道床に敷設されるバラストの平均粒径（５０ｍｍ）と略等しくなるように製した。これにより、前記第１実施形態のまくら木１と同様の理由により、突条あるいは縁材がバラストから安定した抗力を受けることができ、まくら木の位置ずれを効果的に防止可能である。
【０１１４】
また、前記第２〜第１４実施形態のまくら木２採用したまくら木本体及び突条、縁材の素材については特に言及していないが、第１実施形態のまくら木と同様に合成木材を用いて製することにより、製造性、耐久性が向上すると共に軽量化を図ることが可能である。
また、前記本発明のまくら木は、合成木材に限らずコンクリートで製することも可能であり、耐久性、耐摩耗性が向上すると共に、位置ずれを効果的に防止したＰＣ製まくら木とすることができる。
【０１１５】
次に、前記した本発明の実施形態に係るまくら木の形状を定めるのに際して検討した試験まくら木の構造及び道床横抵抗力の試験結果について、図２０を参照して説明する。
標準まくらぎ５０の寸法は、図２０（ａ）の様に、長さ（Ｌ）２２００ｍｍ×幅（Ｗ）２３０ｍｍ×高さ（Ｈ）１４０ｍｍであり、この標準まくら木５０の断面形状を、図２０（ｂ）〜（ｈ）に示すように変えた試験まくら木５１〜５７を試作して道床横抵抗力を求めた。各試験まくら木５１〜５７の形状は次の通りである。
【０１１６】
試験まくら木５１は、図２０（ｂ）の様に、標準まくら木５０の底面中央部に長手方向に沿って全長に渡って幅ｗ１（１２０ｍｍ）、高さｈ１（４０ｍｍ）の断面形状が略半円形の溝部を設けたもので、溝部の角は半径Ｒ（４０ｍｍ）で湾曲させている。
試験まくら木５２は、図２０（ｃ）の様に、標準まくら木５０の底面中央部に長手方向に沿って全長に渡って幅ｗ２（７０ｍｍ）、高さｈ２（３５ｍｍ）の溝を設けた形状である。
【０１１７】
試験まくら木５３（既に特許公告された形状）は、図２０（ｄ）の様に、標準まくら木５０の長手両端部の底面に、幅方向の全長に渡って長さｗ３（１５０ｍｍ）、高さｈ３（４０ｍｍ）の板体（パッキン）を取り付けている。
試験まくら木５４は、図２０（ｅ）の様に、標準まくら木５０の底面中央部に長手方向に沿って全長に渡って幅ｗ４（５０ｍｍ）、高さｈ４（５０ｍｍ）の角材を取り付けた形状である。
【０１１８】
試験まくら木５５は、図２０（ｆ）の様に、標準まくら木５０の底面から長手両側面に渡るコ字状の位置ずれ防止部材５５ａを６個取り付けた構造である。位置ずれ防止部材５５ａは、高さｈ５（５０ｍｍ）、幅ｗ５（５０ｍｍ）の角材をコ字状に接続して形成したものである。
試験まくら木５６は、図２０（ｇ）の様に、前記試験まくら木５１の溝部に、所定間隔をおいて仕切壁５６ａを設けた形状である。
また、試験まくら木５７は、図２０（ｈ）の様に、前記試験まくら木５２の溝部に、所定間隔をおいて仕切壁５７ａを設けた形状である。
【０１１９】
これらの試験まくら木５１〜５７の道床横抵抗力の測定に際しては、試験まくら木５１〜５７の長手方向（道床横方向）へ向けて加重を印加し、試験まくら木の変位量（位置ずれ量）が２ｍｍになったときの荷重を道床横抵抗力とした。結果は表１に示す通りである。
【０１２０】
表１より、底面に溝部を設けた試験まくら木５１，５２では、標準まくら木５０の有する道床横抵抗力３０８（ｋｇｆ）よりも低い略２５０（ｋｇｆ）となった。これは、溝部を設けたために、試験まくら木５１，５２の本体重量が軽くなったためと考えられる。
また、溝部に仕切壁５６ａ，５７ａを設けた試験まくら木５６，６７では、道床横抵抗は略２９０（ｋｇｆ） に増大するものの、標準まくら木５０よりも低い値であった。
【０１２１】
しかし、試験まくら木５３では、まくらぎの断面積が底面側で増加することにより、道床横方向の抵抗力が４２７（ｋｇｆ） となり、標準まくら木５０に比べて略１．４倍に増加している。
また、試験まくら木５４では、道床横方向の抵抗力が４１３（ｋｇｆ） となり、標準まくら木５０に比べて略１．３５倍に増加し、試験まくら木５３と同様の効果がある。これはまくらぎの断面が圧力の大きい底面部で増加し、更に長手方向全長に渡って凸状体を設けることにより、位置ずれ防止効果が大きいと考えられる。
また、試験まくら木５５では、道床横方向の抵抗力が６７０（ｋｇｆ） となり、標準まくら木５０に比べて略２．２倍に増大した。これはまくらぎの断面積が、側面部から底面部にかけて略１．９５倍に増加した形状効果によるものと考えられる。
【０１２２】
【表１】
【０１２３】
【発明の効果】
請求項１〜４に記載の本発明のまくら木によれば、まくら木の道床縦方向あるいは道床横方向への位置ずれを効果的に防止することができる。
請求項５，６に記載の本発明によれば、簡単な構成によって位置ずれの防止効果を一層向上させたまくら木を提供することができる。
請求項７，８に記載の本発明によれば、レールやタイプレートとまくら木との間や、まくら木とバラストとの間に生じる摩擦摩耗の発生を効果的に抑止することができ、耐久性を向上させたまくら木を提供できる。
請求項９〜１３に記載の本発明によれば、耐摩耗性部材の耐久性が向上する共とに、まくら木の位置ずれをも防止する効果を奏するまくら木を提供できる。
【図面の簡単な説明】
【図１】（ａ）は本発明の実施形態に係るまくら木を示す斜視図、（ｂ）は（ａ）の分解斜視図である。
【図２】（ａ）は本発明の別の実施形態に係るまくら木を示す斜視図、（ｂ）は（ａ）の分解斜視図である。
【図３】（ａ）は本発明の別の実施形態に係るまくら木を示す斜視図、（ｂ）は（ａ）の分解斜視図である。
【図４】（ａ）は本発明の別の実施形態に係るまくら木を示す斜視図、（ｂ）は（ａ）の分解斜視図である。
【図５】（ａ）は本発明の別の実施形態に係るまくら木を示す斜視図、（ｂ）は（ａ）のまくら木を底面側から見た分解斜視図である。
【図６】（ａ）は本発明の別の実施形態に係るまくら木を示す斜視図、（ｂ）は（ａ）のまくら木を底面がわら見た分解斜視図である。
【図７】（ａ）は本発明の別の実施形態に係るまくら木を示す斜視図、（ｂ）は（ａ）の分解斜視図である。
【図８】（ａ）は図７に示すまくら木の部分分解斜視図、（ｂ）は（ａ）の斜視図である。
【図９】（ａ）〜（ｄ）は、耐摩耗性部材の形状及びその装着方法を示す斜視図である。
【図１０】（ａ），（ｂ）は、別の耐摩耗性部材の形状及びその装着方法を示す斜視図である。
【図１１】（ａ）〜（ｈ）は、耐摩耗性部材をまくら木に取り付ける場合の取付構造を示す斜視図である。
【図１２】（ａ）は本発明の別の実施形態に係るまくら木を示す斜視図である。
【図１３】（ａ）は図１２に示すまくら木の部分分解斜視図、（ｂ）は図１２に示すまくら木の部分斜視図、（ｃ）は（ｂ）の側面図である。
【図１４】（ａ）は本発明の別の実施形態に係るまくら木を示す斜視図、（ｂ）は（ａ）の部分分解斜視図、（ｃ）は（ａ）のＡ−Ａ矢視断面図、（ｄ）は（ｃ）の円内拡大図である。
【図１５】（ａ）は本発明の別の実施形態に係るまくら木を示す斜視図、（ｂ）は（ａ）の部分分解斜視図、（ｃ）は（ａ）のＡ−Ａ矢視断面図である。
【図１６】（ａ）は本発明の別の実施形態に係るまくら木を示す斜視図、（ｂ），（ｃ）は（ａ）の部分分解斜視図、（ｄ）は（ａ）のＡ−Ａ矢視断面図である。
【図１７】（ａ）は本発明の別の実施形態に係るまくら木を示す斜視図、（ｂ）は（ａ）のまくら木に耐摩耗性部材を取り付ける状態を示す分解斜視図、（ｃ）は（ａ）のまくら木を底面側から見た部分分解斜視図、（ｄ）は（ａ）のまくら木を底面側から見た斜視図である。
【図１８】（ａ）は本発明の別の実施形態に係るまくら木を示す斜視図、（ｂ）は（ａ）のまくら木を底面側から見た分解斜視図、（ｃ）は（ａ）のまくら木を底面側から見た斜視図、（ｄ）は（ｃ）のまくら木に更に突条を追加したまくら木を底面側から見た斜視図である。
【図１９】（ａ）は本発明の更に別の実施形態に係るまくら木を示す斜視図、（ｂ）は（ａ）のまくら木を底面側から見た分解斜視図、（ｃ）は（ａ）のまくら木を底面側から見た斜視図である。
【図２０】（ａ）は標準まくら木の正面図及び側面図、（ｂ）〜（ｈ）は試験まくら木の正面図及び側面図である。
【符号の説明】
１，２，３，４，５，６，７，８ まくら木
９，１０，１１，１２，１３，１４ まくら木
２０ まくら木（本体）
２０ａ まくら木（本体）の上面
２０ｂ まくら木（本体）の底面
２０ｃ まくら木（本体）の長手両側面
２１，２２，２３，２４，２５ａ，２５ｂ 突条
２６，２７，２８，２８’２９ 突条
２５，４０，４１ 縁材
３０，３２ 耐摩耗性部材[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to sleepers, and more particularly, to a sleeper that is prevented from being displaced from a track bed. The present invention also relates to a pillow with reduced wear on the pillow surface.
[0002]
[Prior art]
Conventionally, wooden pillows made of wood or PC (Pressed Concrete) have been generally used. Wooden sleepers are lightweight and resistant to vibrations, but have the drawbacks of short service life and low track bed resistance, and their use tends to be refrained from the depletion of timber resources. On the other hand, sleepers made of PC are strong against bending loads and have a long service life, but they are heavy and dislike the need for large-scale laying work, and are not suitable for branch sections of rails because they are weak against vibration. .
[0003]
Therefore, in recent years, synthetic pillows made of synthetic wood made of fiber-reinforced hard synthetic resin foam have been used as an alternative to these pillows. Synthetic sleepers are not only light, strong and durable, but also resistant to vibration, so they are often used for rail joints and branches.
[0004]
By the way, at the joints and branches of the rails, the vibration accompanying the passage of the train is large, the track consolidation progresses, the track sinks, the track moves up and down, and the pillows are crossed with the track bed (the direction crossing the rail) and the track bed. The so-called "tilt phenomenon" in which a shift occurs in the vertical direction (rail direction) is likely to occur. In particular, the synthetic sleepers are liable to cause the "tilting phenomenon" due to their light weight. Therefore, in the case of the branch pillow made of synthetic wood, measures have been taken to prevent the lateral displacement of the pillow in the lateral direction of the track bed by using a ridge member attached to the bottom surface in advance.
[0005]
Also, as described above, `` tilting phenomenon '' is likely to occur in the branch pillow, and on the top of the pillow, dents are generated due to friction and wear due to contact with the tie plate, and on the bottom and side surfaces of the pillow, due to friction and wear due to contact with the ballast. Dent and damage occur. Therefore, in places where the "tilting phenomenon" is likely to occur, a wear-resistant member such as a rubber plate is attached to the surface of the sleeper to prevent the occurrence of frictional wear.
[0006]
[Problems to be solved by the invention]
However, although the synthetic sleeper provided with the above-mentioned ridge member has the effect of preventing the lateral displacement of the track bed, the effect of preventing the longitudinal displacement of the track bed could hardly be expected.
Also, since the wear-resistant member (rubber material) for preventing frictional wear due to vertical movement and displacement of the sleeper is expensive, it may be stuck to the top of the sleeper but also to the bottom and side surfaces. However, a sufficient abrasion resistance effect was not obtained and there was a problem in durability.
[0007]
The present invention has been proposed in view of such a problem, and an object of the present invention is to provide a sleeper that effectively suppresses a displacement of the sleeper in a vertical direction and a horizontal direction of the track floor. Another object of the present invention is to provide a sleeper with reduced wear and improved wear resistance.
[0008]
[Means for Solving the Problems]
The sleeper according to claim 1 proposed to achieve the object has a configuration in which a ridge extending in a longitudinal direction of the sleeper is formed on a bottom surface of the sleeper.
[0009]
When a ridge extending in the longitudinal direction is formed on the bottom surface of the pillow, the height of the pillow when viewed from the width direction is the sum of the height of the main body portion and the height of the ridge. Therefore, the ballast contact area when the sleeper is viewed from the width direction (vertical direction) is increased, the drag of the ballast (track) against the positional shift of the sleeper increases, and the positional shift in the vertical direction is suppressed. You.
[0010]
In the present invention, a configuration in which the ridge is provided in the center of the bottom of the sleeper in the width direction in the longitudinal direction, or a configuration in which the protrusion is provided in the vicinity of both ends in the width direction of the bottom of the sleeper in the longitudinal direction can be adopted. The ridge may be provided on the bottom surface of the sleeper over the entire length in the longitudinal direction, or may be provided on a part of the longitudinal direction. It is also possible to provide a plurality of ridges extending in the longitudinal direction.
By providing the ridge extending in the longitudinal direction on the bottom surface of the sleeper, the secondary moment of area of the sleeper is increased, and the bending stiffness (EI) in the longitudinal direction can be improved.
[0011]
The ridge can be formed by, for example, joining a square member to the bottom surface of the sleeper wood in the longitudinal direction. In addition, it is also possible to form a pillow having a ridge by cutting a portion other than a portion where the ridge is formed on the bottom surface of the prism using a prism material having a height higher than that of the conventional-sized pillow. .
[0012]
According to a second aspect of the present invention, in the sleeper according to the first aspect, a ridge extending in the height direction of the sleeper is formed on both longitudinal sides of the sleeper.
[0013]
When the ridge extending in the height direction is formed on both longitudinal sides of the sleeper, the width of the pillow when viewed from the longitudinal direction (lateral direction of the roadbed) is the width of the main body portion plus the width of the ridge. Therefore, the ballast contact area when the sleeper is viewed from the lateral side of the track bed increases, and the drag of the ballast against the positional shift of the sleeper increases, thereby suppressing the lateral displacement of the track floor.
[0014]
In the present invention, the ridges extending in the height direction may be provided on both longitudinal sides of the sleeper over the entire length in the height direction, or may be provided on a part of the height direction. It is also possible to provide a plurality of ridges extending in the height direction.
The ridge can be formed, for example, by joining square members to the longitudinal both sides of the sleeper in the height direction. In addition, it is also possible to form a sleeper having a ridge by cutting a portion other than a portion where the ridge is formed on both longitudinal side surfaces of the prism using a wider prism material than the conventional-sized pillow. is there.
[0015]
The invention according to claim 3 has a configuration in which a ridge extending in the width direction of the sleeper is formed on the bottom surface of the sleeper, and a ridge extending in the height direction of the sleeper is formed on both longitudinal sides of the sleeper. Have been.
[0016]
When a ridge extending in the width direction is formed on the bottom surface of the pillow, the height of the pillow when viewed from the longitudinal direction is the sum of the height of the main body portion and the height of the ridge. Accordingly, the ballast contact area when the sleeper is viewed from the longitudinal direction (lateral side of the track) is increased, the drag of the ballast against the positional shift of the sleeper is increased, and the positional shift in the lateral direction of the track is suppressed.
[0017]
In addition, when ridges extending in the height direction are formed on both longitudinal side surfaces of the sleeper, the displacement of the sleeper in the lateral direction of the track bed is suppressed for the same reason as the sleeper according to the second aspect.
In other words, according to the sleeper of the present invention, it is possible to further suppress displacement of the sleeper in the lateral direction of the track bed by the ridges provided on the bottom surface and the both longitudinal side surfaces of the sleeper.
[0018]
According to a fourth aspect of the present invention, in the sleeper according to the third aspect, the ends of the ridge extending in the width direction on the bottom surface of the pillow and the ridges extending in the height direction on both longitudinal sides of the pillow are connected. And are integrally formed.
[0019]
According to the configuration of the present invention, a U-shaped ridge is formed from both longitudinal side surfaces to the bottom surface of the sleeper, and the width and height of the sleeper when viewed from the longitudinal direction are increased, so that the ballast contact area is increased. Thereby, the drag of the ballast against displacement of the pillows in the lateral direction of the track bed is increased, and displacement in the lateral direction of the track bed is suppressed.
[0020]
As a configuration for forming a U-shaped ridge, for example, a square member is formed by joining a bottom surface and both longitudinal side surfaces of a sleeper, or a ridge member in which a square member is joined in a U shape in advance, It is also possible to adopt a configuration of inserting from the bottom surface side and joining to the bottom surface and both longitudinal side surfaces. Further, it is also possible to use an integrated ridge member formed by cutting a square plate material into a U-shape.
[0021]
According to a fifth aspect of the present invention, in the sleeper according to any one of the first to fourth aspects, the ridges have a bottom surface and / or a longitudinal side corresponding to an upper surface portion of the sleeper to which the rail or the tie plate is fixed. It is configured to be provided near the surface portion.
[0022]
All the forces applied to the sleepers as the train passes are transmitted via rails or tie plates. For this reason, if ridges are provided on the bottom surface or on both longitudinal sides away from the part where the rail or tie plate is fixed, the parts where the force is applied to the pillows as the train passes and the parts where the drag of the ballast is added The spacing of the pillows increases, and the pillow is likely to bend or buckle.
[0023]
According to the present invention, the ridges are provided on the bottom surface and the longitudinal side surfaces corresponding to the fixing portions of the rail and the tie plate, so that the reaction force from the ridge is applied near the portion to which the force transmitted from the rail or the tie plate is applied. Thereby, it is possible to effectively suppress the displacement of the sleeper in the lateral direction of the track bed and in the vertical direction of the track bed, while suppressing the bending and buckling of the sleeper.
[0024]
According to a sixth aspect of the present invention, in the sleeper according to any one of the first to fifth aspects, the ridge has an average particle size of a ballast laid on a track with a protrusion length of the ridge from the surface of the pillow. The diameter is substantially equal to the diameter.
[0025]
Here, when the protrusion length of the ridge from the pillow surface is significantly smaller than the average particle size of the ballast, the increase in the ballast contact area when the pillow is viewed from the longitudinal direction or the width direction is extremely small. For this reason, the increase in the drag of the ballast is so small that an improvement in the effect of suppressing the displacement cannot be expected.
On the other hand, when the protrusion length of the ridge from the surface of the pillow is larger than the average particle size of the ballast, the effect of suppressing displacement can be improved by increasing the ballast contact area, but on the other hand, the protrusion length of the ridge increases. As a result, the workability of laying the pillows is significantly reduced.
[0026]
The protrusion length of the ridge from the surface of the pillow should be substantially equal to the average particle size of the ballast. When the projection length of the ridge is approximately equal to the average particle size of the ballast, the projection length of the ballast in contact with the surface of the sleeper is approximately equal to the projection length of the ridge, and the center of the ballast is in contact with the tip of the ridge. The contact state is unlikely to occur. As a result, when a force causing a displacement in the longitudinal direction or the width direction is applied to the pillow, it is unlikely that the leading end of the ridge slips over the ballast and the displacement is reduced due to stable drag. It can be prevented.
[0027]
The invention according to claim 7 is configured such that a wear-resistant member is attached to a top surface portion of a sleeper to which a rail or a tie plate is fixed, and a bottom portion and a longitudinal side portion corresponding to the top surface portion. .
[0028]
With the passage of the train, the sleepers are subjected to a large force in the downward direction, in the vertical direction of the track bed, or in the horizontal direction of the track bed, so that the track bed at the bottom of the sleeper is compacted and the track goes up and down. A dent is generated on the upper surface of the sleeper due to frictional wear with the tie plate, and a dent or damage is easily generated on the bottom surface or the longitudinal side surface of the sleeper due to frictional wear with the ballast.
[0029]
According to the present invention, as described above, the wear-resistant member is attached to the top portion of the sleeper to which the rail or tie plate is fixed, and to the bottom portion and the longitudinal side portions corresponding to the top portion. Generation of friction and wear with the ballast and tie plate and friction and wear with the ballast can be effectively suppressed.
As the abrasion-resistant member, any suitable one can be adopted. However, if a general synthetic rubber such as chloroprene rubber (CR) or styrene-butadiene rubber (SBR) is used, sufficient abrasion resistance can be achieved while reducing costs. Ability can be exhibited.
[0030]
In the present invention, the wear-resistant member can take various shapes. For example, a configuration in which a plate-shaped wear-resistant member is individually joined to each of the top surface, the bottom surface, and both longitudinal side surfaces of the sleeper can be adopted.
Further, an integrated wear-resistant member in which a portion located on the upper surface or the bottom surface of the rectangular cylindrical shape covering the upper surface from the upper surface to the both side surfaces and the bottom surface of the sleeper is cut off can be used. According to this configuration, it is possible to easily attach and attach the wear-resistant member to the sleeper while spreading the separated portion.
[0031]
Further, a configuration using a pair of abrasion-resistant members having a U-shaped cross section formed separately from the left and right can be adopted. According to this configuration, it is possible to easily attach the pair of wear-resistant members from the width direction of the sleeper while the sleeper is laid.
[0032]
Further, the abrasion-resistant member has a shape having at least a larger area on the upper surface of the sleeper than a portion where the tie plate comes into contact with the sleeper, so that frictional wear due to the tie plate can be effectively suppressed.
Even at the bottom and both sides of the sleeper, by providing a wear-resistant member at least in a portion corresponding to a portion where the tie plate is fixed to the upper surface of the sleeper, it is possible to effectively prevent frictional wear due to ballast. .
[0033]
In the present invention, various structures can be adopted as a structure for attaching the wear-resistant member to the surface of the sleeper. For example, an attachment structure in which a wear-resistant member is directly attached to the top, bottom, and both sides of the sleeper can be employed.
In addition, by forming a band-shaped groove having a depth substantially equal to the thickness of the wear-resistant member on the upper surface of the pillow, and fitting and attaching the wear-resistant member to the groove, the upper surface of the pillow and the wear-resistant member are removed. Can be formed on the same surface as the mounting structure. Further, it is also possible to adopt a mounting structure in which similar grooves are provided on the bottom surface and both longitudinal sides of the sleeper, and the wear-resistant members located on the bottom surface and both longitudinal sides form the same surface as the surface of the sleeper.
[0034]
According to an eighth aspect of the present invention, in the sleeper according to the seventh aspect, the wear-resistant member is formed such that a contact portion with the bottom surface of the sleeper is longer in a longitudinal direction of the sleeper than a contact portion with the upper surface. The contact portions of the sleeper with respect to the longitudinal both side surfaces are formed so as to become wider from the upper surface side to the bottom surface side.
[0035]
As mentioned above, all the forces associated with the passage of the train are transmitted to the sleepers via rails or tie plates. Therefore, the force applied to the abutment portion of the rail or the tie plate on the upper surface of the sleeper causes a frictional motion at a portion that spreads in the longitudinal direction as approaching the bottom side according to the rigidity of the sleeper. For this reason, a portion closer to the bottom surface of the sleeper is more likely to generate dents and damage due to friction and wear in a wider range than the top surface.
According to the present invention, by forming the wear-resistant member longer in the longitudinal direction toward the bottom of the sleeper, it is possible to cover a portion where friction and wear are likely to occur and prevent dents and damage from occurring. Become.
[0036]
According to a ninth aspect of the present invention, in the sleeper according to the seventh or eighth aspect, an edge material is attached to a bottom surface and / or both longitudinal side surfaces of the sleeper along a side edge of the wear-resistant member. ing.
[0037]
When pillows are laid on the roadbed, most of the bottom and both sides are buried in the ballast. For this reason, in the sleeper according to the seventh or eighth aspect, a problem that the ballast bites into the side edge of the wear-resistant member attached to the sleeper and peels off easily occurs. In particular, in a mounting structure in which a wear-resistant member is protruded and joined to the bottom surface and both longitudinal side surfaces of the sleeper by the thickness thereof, a step occurs between a side edge of the wear-resistant member and the surface of the sleeper, so that a side difference is generated. Ballast is more likely to bite into the rim.
[0038]
However, according to the present invention, by attaching the edge material along the side edge of the wear-resistant member, the side edge of the wear-resistant member is protected, the peeling due to the penetration of the ballast is prevented, and the durability is improved.
When the abrasion-resistant member adopts a shape in which a portion located on the bottom surface of the above-described square cylindrical shape or a U-shaped cross section formed by separating the left and right sides is used, the abrasion resistance on the bottom surface of the sleeper is provided. An edge material may be provided along a side edge of a portion where the sex member is separated. According to this configuration, the side edge of the wear-resistant member is protected by the rim material, so that the ballast can be prevented from peeling off due to bite.
For the edge material, for example, a plate material having an appropriate thickness can be used.
[0039]
According to a tenth aspect of the present invention, in the sleeper according to the ninth aspect, the edge material has a projection length of the edge material from the surface of the sleeper that is greater than or equal to a projection length of the wear-resistant member from the surface of the sleeper. The configuration is such that the length of the edge material protruding from the surface of the pillow is substantially equal to the average particle size of the ballast laid on the track.
[0040]
Here, when the edge material is required to have only the function of improving the durability of the wear-resistant member, the length of the edge material protruding from the pillow surface is equal to or longer than the length of the wear-resistant member protruding from the pillow surface. It is preferable that the shapes be substantially equal. Thereby, the surface of the wear-resistant member and the surface of the edge material form substantially the same plane, and the side edge of the wear-resistant member is protected by the edge material, thereby preventing the ballast from biting. In this configuration, a plate having the same thickness as the wear-resistant member can be employed as the edge member.
[0041]
On the other hand, if the edge material is required to have the function of preventing the displacement of the sleepers in addition to the function of improving the durability of the wear-resistant member, the edge materials should be laid on the track with the protruding length from the surface of the sleepers. It is preferable to use a ridge shape substantially equal to the average particle size of the ballast to be formed. According to this configuration, the side edges of the wear-resistant member are protected by the edge material, and for the same reason as the sleeper according to the fifth aspect, the edge material having a ridge shape can reduce the displacement of the sleeper. Can be deterred. In this configuration, it is possible to use, as an edge material, a square material having a height substantially equal to the average particle size of the ballast.
[0042]
According to an eleventh aspect of the present invention, in the sleeper according to any one of the seventh to tenth aspects, a portion of the bottom surface of the sleeper to which the wear-resistant member is not attached is provided in a longitudinal direction of the sleeper and / or a sleeper. It is configured such that a ridge extending in the width direction is formed.
[0043]
According to the present invention, frictional wear of the sleeper is suppressed by the wear-resistant member and durability is improved. In addition, for the same reason as the sleeper described in the above-mentioned claims 1, 3, the trackbed is in the lateral direction or the trackbed. The displacement in the vertical direction can be effectively suppressed.
Further, in the present invention, when a wear-resistant member having a shape cut off at the bottom of the sleeper is adopted, a ridge may be formed in the cut-off portion of the bottom along the longitudinal direction. According to this configuration, the displacement of the sleeper in the vertical direction of the roadbed is suppressed, and the side edge of the wear-resistant member is protected, thereby improving the durability.
[0044]
According to a twelfth aspect of the present invention, in the sleeper according to any one of the seventh to tenth aspects, a portion of the bottom surface of the sleeper to which the wear-resistant member is attached is provided in the longitudinal direction of the sleeper and / or in the sleeper. It is configured such that a ridge extending in the width direction is formed.
[0045]
According to the present invention, wear of the sleeper is suppressed by the wear-resistant member, and the durability is improved. In addition, for the same reason as the sleeper described in the above-described claims 1 and 3, the track bed lateral direction and the track bed longitudinal direction are used. The displacement in the direction can be effectively suppressed centering around the position of the track portion.
[0046]
According to a thirteenth aspect of the present invention, in the sleeper according to the eleventh or twelfth aspect, the protruding length of the ridge is substantially equal to the average particle size of the ballast laid on the track. It has the same configuration.
According to the present invention, the friction wear of the sleeper is suppressed, the durability is improved, and for the same reason as the sleeper described in the above-mentioned claim 6, the shift of the sleeper in the lateral direction of the track bed and / or in the vertical direction of the track bed. Can be effectively prevented.
[0047]
Here, in the sleeper according to the first to thirteenth aspects, the sleeper can be made of concrete. Here, the concrete sleepers refer to those made of PC (Pressure-Concrete) in which steel material to which stress has been applied in advance is built in concrete and fixed integrally. At the time of manufacturing, concrete is poured into a molding die in which ridges and rims are formed in advance and hardened, whereby a concrete sleeper in which ridges and rims are integrally formed can be obtained.
According to the sleeper made of PC, it is possible to construct a sleeper that suppresses displacement in the lateral direction of the track bed and / or the vertical direction of the track bed while making use of the advantages of wear resistance and low cost.
[0048]
In the pillows according to the first to thirteenth aspects, the pillows, the ridges and the edge material can be manufactured using synthetic wood made of a long fiber reinforced hard synthetic resin foam. In particular, if the pillow is made of a glass fiber reinforced hard resin foam plate that is not deteriorated by ultraviolet light, durability and workability can be improved and the weight can be reduced.
The stress applied to the sleeper is mainly caused by a bending moment with the rail as a fulcrum, and a high bending rigidity (EI) in the longitudinal direction of the sleeper is required. Therefore, when the pillows, ridges, and rims are made of synthetic wood, it is preferable that the direction of the fibers contained in the synthetic wood be the longitudinal direction of each member. That is, high bending rigidity can be obtained by using a synthetic wood in which the fiber direction is adjusted to the longitudinal direction of each member or a member in which synthetic woods having different fiber directions are laminated.
[0049]
The glass long fiber reinforced hard synthetic resin foam contains inorganic fibers such as glass fibers, carbon fibers, metal fibers, and ceramic fibers, synthetic fibers such as aromatic polyamide fibers, and organic fibers such as natural fibers as a reinforcing material, and a matrix. Examples include foams such as thermosetting resins such as urethane resins, epoxy resins, vinyl ester resins, unsaturated polyester resins, and phenol resins. In addition, in order to improve compressive strength and reduce costs, inorganic fillers such as calcium carbonate, gypsum, talc, aluminum hydroxide, and clay in foamed resin, and lightweight aggregates such as shirasu balloons, pearlite, and glass balloons May be added. Among them, a suitable material is a foam in which a hard urethane resin is reinforced with long glass fibers, and for example, a product name “Eslon Neo Lumber FFU” (manufactured by Sekisui Chemical Co., Ltd.) is exemplified.
[0050]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1A is a perspective view showing a sleeper 1 according to the first embodiment, and FIG. 1B is an exploded perspective view of FIG.
The sleeper 1 is formed by joining a square member 21 over the entire length in the longitudinal direction to a central portion in the width direction of a bottom surface 20b of a sleeper body 20 of a normal size to form a ridge 21. The timber 21 has a height close to the average particle size of the ballast laid on the roadbed. In the present embodiment, the height of the timber 21 is 50 mm.
In the present embodiment, synthetic wood made of long glass fiber reinforced hard urethane resin foam is used for the sleeper body 20 and the square member 21 that constitute the sleeper 1.
[0051]
According to the pillow 1, as shown in FIG. 1A, the height of the pillow 1 when viewed from the A direction (rail direction: vertical direction of the track bed) is equal to the height of the pillow body 20. 21 and the ballast contact area in the vertical direction of the track bed increases as compared with the case where the ridge 21 is not provided. Thereby, the drag of the ballast against the force applied to the pillow tree 1 in the vertical direction of the track bed increases, and the displacement in the vertical direction of the track bed is suppressed.
[0052]
Further, in the sleeper 1 of the present embodiment, since the protrusion length of the ridge 21 is substantially equal to the average particle diameter of the ballast, the protrusion length of the ballast in contact with the bottom surface 20b of the sleeper is substantially equal to the protrusion length of the ridge 21. As a result, the center of the ballast is less likely to abut against the leading end of the ridge, and when a force is applied to the pillow in the vertical direction of the roadbed, the leading end of the ridge 21 slips over the ballast. Is less likely to occur, and the ridge 21 can receive a stable drag from the ballast to prevent the displacement.
[0053]
In this embodiment, the ridges 21 are formed by joining the square members 21 to the pillow main body 20. For example, the vicinity of the both longitudinal edges of the bottom surface of the synthetic wood prism member having a higher size than the normal size is defined in the longitudinal direction. It is also possible to cut over the entire length to form a longitudinally extending ridge integrated with the sleeper.
[0054]
Further, the sleeper 1 of the present embodiment has a structure in which a prism material is attached to the bottom surface 20b of the normal-size sleeper body 20, the cross-sectional area of the sleeper increases at the bottom, and the prism material is attached over the entire length in the longitudinal direction. As a result, the contact area with the ballast increases, the lateral resistance of the roadbed increases, and as a result, the displacement in the lateral direction of the roadbed is suppressed.
[0055]
FIG. 2A is a perspective view showing the sleeper 2 according to the second embodiment, and FIG. 2B is an exploded perspective view of FIG.
The sleeper 2 is formed by joining four square members 22 to the bottom surface 20b of the sleeper body 20 to form the ridges 22. The square member 22 has a length extending from the longitudinal end of the sleeper body 20 to a portion beyond the fixing position of the tie plate T in the longitudinal direction, and the square member 22 is attached to the bottom surface 20b of the sleeper body 20 at both longitudinal ends. And four are joined along both longitudinal side edges.
[0056]
According to the sleeper 2, as shown in FIG. 2A, the height of the tie plate T in the vicinity of the fixed portion when viewed from the A direction is the same as the height of the sleeper main body 20 as a ridge (square). 22 and the ballast contact area increases as compared with the case where the ridge 22 is not provided. Thereby, the drag of the ballast against the force applied to the pillow 2 in the vertical direction of the track bed increases, and the positional displacement in the vertical direction of the track bed is suppressed.
[0057]
In addition, the sleeper 2 of the present embodiment adopts a shape in which the tie plate T to which the force transmitted from the rail is applied and the ridge 22 to which the drag from the ballast is applied are arranged close to each other. It is possible to effectively suppress the displacement in the vertical direction of the track bed while suppressing the occurrence of the bending due to the drag to suppress the generation of the friction due to the bending.
When the pillow 2 is laid on the roadbed, a ballast is inserted into a gap between the ridges 22 and 22 formed to face the bottom surface 20b to generate a large frictional force on the ridges 22, and the pillows 2 extend vertically. The effect of suppressing displacement is increased.
[0058]
Also, in the sleeper 2 of the present embodiment, similarly to the case of FIG. 1, the cross-sectional area of the sleeper increases at the bottom, the contact area with the ballast in the longitudinal direction increases, and the roadbed lateral resistance improves. The displacement in the lateral direction of the track bed is also suppressed.
[0059]
FIG. 3A is a perspective view showing the sleeper 3 according to the third embodiment, and FIG. 3B is an exploded perspective view of FIG. The sleeper 3 is formed by joining square members 23, 24 to the bottom surface 20 b of the sleeper body 20 to form ridges 23, 24.
[0060]
The square member 23 has a length extending from the longitudinal end of the sleeper body 20 toward the center in the longitudinal direction to a position beyond the fixing position of the tie plate T. And four are joined along both longitudinal side edges. The square member 24 is joined to the bottom surface 20b of the pillow main body 20 in the width direction so as to bridge between the longitudinal ends of the opposed square members 23, 23. That is, the pillow 3 forms a ridge 23 extending in the longitudinal direction and a ridge 24 extending in the width direction on the bottom surface 20 b of the pillow main body 20.
[0061]
According to the sleeper 3, as shown in FIG. 3A, the ballast contact area when the sleeper 3 is viewed from the direction B (the lateral direction of the roadbed: the direction perpendicular to the rail) is smaller than the case where the ridge 24 is not provided. Increase. Thereby, the drag of the ballast against the force applied to the pillow 3 in the lateral direction of the track bed increases, and the displacement in the lateral direction of the track bed is suppressed, and the ridge 23 allows the pillow 2 of the second embodiment to be restrained. In the same manner as described above, the displacement of the roadbed in the vertical direction is suppressed.
[0062]
Further, when the pillow 3 is laid on the track bed, the ballast fits into the inside of the rectangular frame formed by the ridges 23 and 24 on the bottom surface 20b, and the frictional force against the ridges 23 and 24 becomes large. The effect of suppressing displacement in the direction is increased.
When a wear-resistant material is attached to the bottom of the pillow inside the rectangular frame formed by the ridges 23 and 24, the pillow is less likely to be peeled off, and the durability can be improved.
[0063]
FIG. 4A is a perspective view showing the sleeper 4 of the fourth embodiment, and FIG. 4B is an exploded perspective view of FIG. The sleeper 4 is formed by joining a U-shaped misalignment preventing member 25 extending from the bottom surface 20b to the longitudinal side surfaces 20c of the sleeper body 20 to the sleeper body 20, thereby forming protrusions 25a and 25b.
[0064]
As shown in FIG. 4B, the displacement prevention member 25 includes a horizontal portion 25a extending in the width direction along the bottom surface 20b of the sleeper body 20, and two longitudinal side surfaces 20c of the sleeper body 20 from both ends of the horizontal portion 25a. The horizontal portion 25a and the vertical portion 25b have a rectangular cross section. The two displacement prevention members 25 are fixed to the vicinity of both ends of the fixing portion of the tie plate T, respectively.
[0065]
According to the sleeper 4, as shown in FIG. 4A, the ballast contact area when the sleeper 4 is viewed from the direction B (the lateral direction of the roadbed) is increased as compared with the case where the displacement prevention member 25 is not provided. . Thereby, the drag of the ballast against the force applied to the pillow 4 in the lateral direction of the track bed increases, and the positional displacement in the lateral direction of the track bed is suppressed.
In this embodiment, the misalignment preventing member 25 formed integrally is used. However, it is also possible to form a misalignment preventing member 25 having the same shape by joining square members, for example.
[0066]
FIG. 5A is a perspective view showing the sleeper 5 according to the fifth embodiment, and FIG. 5B is an exploded perspective view of the sleeper 5 of FIG.
The sleeper 5 of the present embodiment has a configuration in which a ridge extending in the longitudinal direction is added to the sleeper 4 of the fourth embodiment.
That is, the pillow 5 is formed by joining the square members 26 between the horizontal portions 25a of the lateral misalignment preventing member 25 arranged adjacent to the fixing portion of the tie plate T in the pillow 4 to form a ridge. 26 is formed. The timber 26 is provided so as to connect the central portions of the horizontal portions 25a of the member 25 for preventing displacement in the lateral direction of the track bed, whereby the ridges 26 extend in the longitudinal direction to the central portion in the width direction of the bottom surface 20b of the sleeper body 20. Formed towards.
[0067]
According to the sleeper 5, as shown in FIG. 5A, the ballast contact area when the sleeper 5 is viewed from the A direction (vertical direction of the roadbed) is increased as compared with the case where the ridge 26 is not provided. Thus, in addition to the effect of preventing the lateral shift of the track bed shown in the pillow 4 of the fourth embodiment, the ballast resistance against the force applied to the pillow 5 in the vertical direction of the bed is increased, and The displacement in the direction is suppressed. That is, the pillow 5 is suppressed from being displaced in both the horizontal direction and the vertical direction.
[0068]
FIG. 6A is a perspective view showing the sleeper 6 according to the sixth embodiment, and FIG. 6B is an exploded perspective view of FIG.
In the sleeper 5 according to the fifth embodiment, the ridge 26 is formed between the misalignment preventing members 25 arranged adjacent to the fixing portion of the tie plate T.
On the other hand, the sleeper 6 of the present embodiment has a central portion in the width direction of the bottom surface 20b of the sleeper body 20 in a portion except between the displacement prevention members 25 arranged adjacent to the fixing portion of the tie plate T. Are provided with square members 27, 28 in the longitudinal direction to form ridges 27, 28.
[0069]
In other words, the timber 27 is joined between the roadbed lateral displacement prevention member 25 located at the longitudinal ends of the sleeper body 20 and the longitudinal end of the sleeper body 20 to form the ridges 27. Further, the square members 28 are joined between the positional deviation prevention members 25 in the lateral direction of the roadbed located inside the longitudinal direction of the sleeper body 20 to form the ridges 28.
[0070]
According to the pillow 6, the ridges 27 and 28 are longer than the ridges 26 of the pillow 5 of the fifth embodiment, and as shown in FIG. The resistance of the ballast against the force applied toward the road further increases, and the displacement in the vertical direction of the track bed can be effectively suppressed. That is, displacement of the pillow 6 in both the horizontal direction and the vertical direction is suppressed.
[0071]
Next, FIG. 7 is a perspective view showing a sleeper 7 according to a seventh embodiment.
The sleeper 7 according to the present embodiment has a wear-resistant member 30 attached in a belt shape along the surface near a fixing portion of the tie plate T of the sleeper body 20.
That is, the abrasion-resistant member 30 is attached to the tie plate fixing portion 20d of the sleeper body 20, and the portions of the bottom surface 20b and the longitudinal side surfaces 20c corresponding to the fixing portion 20d.
[0072]
The abrasion-resistant member 30 is formed with an upper surface portion 30a, a bottom surface portion 30b, and a side surface portion 30c, and these portions are joined to the upper surface 20a, the bottom surface 20b, and both longitudinal side surfaces 20c of the sleeper body 20.
The upper surface portion 30a of the wear-resistant member 30 has a larger area than the tie plate fixing portion 20d, and when fixing the tie plate T to the pillow main body 20, the upper surface portion 30a is located between the tie plate T and the pillow main body 20. The abrasion resistant member 30 is attached with it interposed. The length of the bottom surface 30b and the side surface 30c of the wear-resistant member 30 in the longitudinal direction of the sleeper body 20 is the same as that of the upper surface 30a.
[0073]
When the sleeper 7 according to the present embodiment is laid on the roadbed, the lower surface of the bottom surface 20b and the lower longitudinal sides 20c of the sleeper body 20 are buried in the ballast. However, since the wear-resistant member 30 is attached, the friction generated between the tie plate T and the tie plate fixing portion 20d of the sleeper body 20, and the ballast between the bottom surface 20b and the longitudinal side surfaces 20c of the sleeper body 20 and the ballast. Abrasion resistance is exhibited with respect to the friction generated between the pillows, and dents and damages on the surface of the sleeper body 20 are prevented.
[0074]
As the wear-resistant member 30, a synthetic rubber material or a synthetic resin material having elasticity can be used. For example, chloroprene rubber (CR), styrene butadiene rubber (SBR), urethane rubber, isocyanate resin, or the like can be used. it can. Among them, generally used chloroprene rubber and styrene butadiene rubber are suitable because they are inexpensive and exhibit sufficient abrasion resistance.
[0075]
By the way, in the sleeper 7 of the present embodiment, the wear-resistant member 30 attached to the sleeper body 20 can take various shapes.
For example, as shown in FIG. 8A, the wear-resistant member 30 can be formed of four separated plate members of an upper member 30a, a lower member 30b, and side members 30c, 30c.
Then, these members are joined to the upper surface 20c, the bottom surface 20b, and both longitudinal side surfaces 20c, 20c of the sleeper body 20 with a resin adhesive or the like, and the wear-resistant member 30 is attached to the surface of the sleeper body 20. it can.
In this configuration, as shown in FIG. 8B, the abrasion-resistant member 30 is joined in a state of protruding from the surface of the pillow main body 20 by the thickness thereof.
[0076]
Also, as shown in FIG. 9A, the wear-resistant member 30 is formed by forming the wear-resistant member 30 along the surface of the sleeper body 20 into a rectangular cylindrical shape having a flat portion 30a, a side portion 30c, and a bottom portion 30b. It is also possible to form an integrated shape in which a cut-off portion 30d is provided on the 30b in the longitudinal direction.
[0077]
As shown in FIG. 9A, the wear-resistant member 30 is inserted by being inserted from the longitudinal end of the pillow main body 20 while slightly expanding the side surfaces 30c, 30c outward. As shown in (b), the side portions 30c, 30c can be mounted on the pillow main body 20 from the upper surface 20a while being spread outward.
Further, the wear-resistant member 30 is attached such that the detaching portion 30d is located on the bottom surface 20b of the sleeper body 20, as shown in FIG. 9C, or conversely, as shown in FIG. It can be mounted so that the part 30d is located on the upper surface 20a of the sleeper body 20.
[0078]
Further, as another shape of the wear-resistant member 30, as shown in FIG. 10A, a configuration in which a pair of groove-shaped members 31, 31 having a U-shaped cross section separated into right and left can be adopted. . That is, the groove-shaped member 31 is provided with a flat portion 30a, a side portion 30c, and a bottom portion 30b so as to be along the upper surface 20a, the longitudinal side surfaces 20c, and the bottom surface 20b of the sleeper body 20, and has a U-shaped cross section. It is a member.
The abrasion-resistant member 30 can be mounted by covering a pair of groove-shaped members 31 from both sides so as to sandwich the longitudinal both side surfaces 20c of the pillow main body 20, and the abrasion-resistant member 30 in a state where the pillow 7 is laid down. Can be attached.
When the wear-resistant member 30 is attached to the sleeper body 20, a cut-off portion 31d is formed on the top surface 20a and the bottom surface 20b in the longitudinal direction.
[0079]
Here, the abrasion-resistant member 30 shown in FIGS. 8 to 10 is preferably formed by shaping a material by profile extrusion. By manufacturing the wear-resistant member 30 using this molding method, the shape is stabilized, and peeling is less likely to occur when the wear-resistant member 30 is joined to the sleeper body 20.
[0080]
On the other hand, various attachment structures can be used for attaching the wear-resistant member 30 to the surface of the sleeper body 20.
For example, as shown in FIGS. 11A and 11B, the upper surface portion 30a, the lower surface portion 30b, and the side surface portion 30c of the wear-resistant member 30 are provided on the upper surface 20a, the bottom surface 20b, and both longitudinal side surfaces 20c of the sleeper body 20. It is possible to adopt a configuration of joining by projecting only by the thickness.
[0081]
In addition, as shown in FIG. 11C, a band-shaped groove 21 having a depth substantially equal to the thickness of the wear-resistant member 30 is previously formed on the upper surface 20a of the sleeper body 20 over the entire length in the width direction. It is possible to adopt a configuration in which the upper surface portion 30a of the sex member 30 is fitted into the groove portion 21 to be fitted. According to this configuration, as shown in FIG. 11D, the upper surface portion 30a of the wear-resistant member 30 and the upper surface portion 20a of the sleeper body 20 are substantially flush with each other. The member 30 protrudes by its thickness.
[0082]
As shown in FIG. 11E, a band-like groove 22 having a depth substantially equal to the thickness of the wear-resistant member 30 is also formed on the bottom surface 20b of the sleeper body 20 in the width direction so as to face the groove 21 on the upper surface 20a. A configuration may be adopted in which the upper surface portion 30a and the bottom surface portion 30b of the wear-resistant member 30 are fitted into the grooves 21 and 22, respectively, and are formed over the entire length. According to this configuration, as shown in FIG. 11F, the upper surface portion 30a and the bottom surface portion 30b of the wear-resistant member 30 are substantially flush with the upper surface 20a and the bottom surface 20b of the sleeper body 20, respectively. On both side surfaces 20c, the wear resistant member 30 protrudes by its thickness.
[0083]
Further, as shown in FIG. 11 (g), corresponding to the grooves 21 and 22 provided on the upper surface 20a and the bottom surface 20b of the sleeper body 20, the longitudinal side surfaces 20c have a depth substantially equal to the thickness of the wear-resistant member 30. The belt-like grooves 23, 23 are formed over the entire length in the height direction, and all of the upper surface 30a, the bottom surface 30b, and the side surface 30c of the wear-resistant member 30 are fitted into the grooves 21, 22, 23, respectively. A configuration for mounting can be adopted. According to this configuration, as shown in FIG. 11 (h), the pillow main body 20 and the surface of the wear-resistant member 30 are all mounted on the same plane.
[0084]
In the mounting structure of the wear-resistant member 30 shown in FIGS. 11A to 11H, if the surface of the pillow main body 20 and the surface of the wear-resistant member 30 form substantially the same plane, At the time of laying, the ballast is unlikely to bite into the side edge of the wear-resistant member 30, and the ballast is prevented from peeling, so that the durability can be improved.
The sleeper 7 of the present embodiment is formed by appropriately combining the shape of the wear-resistant member 30 shown in FIGS. 8 to 10 and the mounting structure of the wear-resistant member 30 shown in FIG. Is possible.
[0085]
FIG. 12 is a perspective view showing the sleeper 8 according to the eighth embodiment, and FIG. 13 is an exploded perspective view, a perspective view, and a side view showing an attached state of the wear-resistant member of the sleeper 8. The sleeper 8 according to the present embodiment is obtained by partially changing the configuration of the sleeper 7 according to the seventh embodiment.
[0086]
That is, as shown in FIG. 13 (a), the sleeper 8 has an upper surface member 32a, a lower surface member 32b, and a side surface member 32c which form the wear-resistant members 30 on the upper surface 20a, the bottom surface 20b, and both longitudinal side surfaces 20c of the sleeper body 20. As shown in FIG. 13B, the abrasion-resistant member 32 is attached by protruding from the surface of the sleeper body 20 by the thickness thereof.
[0087]
As shown in FIG. 13A, the wear-resistant member 32 used for the sleeper 8 is the same as the wear-resistant member 30 used in the seventh embodiment for the upper surface member 32a that contacts the upper surface 20a of the sleeper body 20. Shape.
On the other hand, the bottom member 32b abutting on the bottom surface 20b of the sleeper body 20 is formed longer in the longitudinal direction of the sleeper body 20 than the upper surface member 32a, and the side members 32c abutting on both longitudinal sides of the sleeper body 20 are from the upper surface side. It is formed so that it becomes wider toward the bottom surface side.
[0088]
Here, in this embodiment, as shown in FIG. 13C, the shape of the side member 32c of the wear-resistant member 32 is a trapezoidal shape, and the angle θ formed by the bottom side and the inclined side of the side member 30c is approximately 45 degrees. Is formed. Due to the force applied to the upper surface 20a of the sleeper body 20 via the tie plate T, the range in which friction occurs in the longitudinal direction as it approaches the bottom surface 20b in accordance with the rigidity of the sleeper body 20 increases. In addition, it is possible to effectively suppress damage caused by friction and wear.
[0089]
If the angle θ is smaller than 45 degrees, the area of the side surface member 30c and the bottom surface member 30b is reduced, and it is not possible to cover a portion where friction easily occurs. When the angle θ is larger than 45 degrees, the portion where friction easily occurs can be sufficiently covered, but the area of the side member 30c and the bottom member 30b increases, and the cost increases.
The optimum angle θ between the bottom side and the inclined side of the side member 30c is approximately 45 degrees.
[0090]
Further, in the present embodiment, the configuration in which the upper surface member 32a, the bottom surface member 32b, and the side surface member 32c which form the wear-resistant member 32 on each surface of the pillow main body 20 is employed, for example, as shown in FIG. In addition, it is also possible to use a wear-resistant member integrally formed, and as shown in FIG. 10, it is also possible to use a wear-resistant member obtained by combining a pair of separated groove-shaped members. It is.
Also, the structure shown in FIG. 11 can be appropriately adopted as the structure for attaching the wear-resistant member 32 to the sleeper body 20.
[0091]
14A is a perspective view showing the sleeper 9 of the ninth embodiment, FIG. 14B is a partially exploded perspective view, FIG. 14C is a cross-sectional view taken along the line AA of FIG. 14A, and FIG. FIG.
In the sleeper 9 of the present embodiment, in the sleeper 7 of the seventh embodiment, the edge members 40 and 41 are joined to the bottom surface 20b and both longitudinal side surfaces 20c of the sleeper body 20 along the side edges of the wear-resistant member 30. Things.
The wear-resistant member 30 is formed by joining an upper surface member 30a, a bottom surface member 30b, and a side member 30c to the surface of the sleeper body 20 as shown in FIG. 14B (see FIG. 8). An attachment structure (see FIG. 11B) in which the wear-resistant member 30 protrudes from the surface by the thickness thereof is employed.
[0092]
As shown in FIG. 14B, the rim member 40 is a flat plate member that is slightly thicker than the abrasion-resistant member 30 and has a length substantially equal to the width of the pillow main body 20. It is joined to the bottom surface 20b of the pillow main body 20 so as to abut the side edge of the bottom member 30b of the member 30. The edge members 40 are respectively joined to two opposing side edges of the bottom member 30b of the wear-resistant member 30.
[0093]
The rim member 41 is a flat plate having the same thickness as the rim member 40 and having a length substantially equal to the height of the pillow main body 20, and has a longitudinal side edge formed by the side member 30 c of the wear-resistant member 30. Are joined to both longitudinal side surfaces 20c of the pillow body 20 so as to abut against the side edges of the pillow. The edge members 41 are respectively joined to two opposing side edges of the side member 30c of the wear-resistant member 30.
[0094]
When the edge members 40 and 41 are joined to the bottom surface 20b and the longitudinal side surfaces 20c of the sleeper body 20, the bottom member 30b and the side members of the wear-resistant member 30 are provided as shown in FIGS. The edge members 40 and 41 are attached with their surfaces slightly projecting from the surface of 30c.
Therefore, when the pillow 9 is laid on the roadbed, the side edges of the wear-resistant members 30b, 30c are completely protected by the edge members 40, 41, so that the ballast is prevented from being bitten, and the wear-resistant member 30 is prevented from peeling off. It is possible to improve the performance.
[0095]
15A is a perspective view showing the sleeper 10 of the tenth embodiment, FIG. 15B is a partially exploded perspective view of FIG. 15A, and FIG. 15C is a cross-sectional view of FIG.
The sleeper 10 according to the present embodiment is obtained by changing the shapes of the edge members 40 and 41 of the sleeper 9 shown in the ninth embodiment.
[0096]
The rim member 25 used for the sleeper 10 has the same shape as the misalignment preventing member 25 used for the sleeper 4 (see FIG. 4) of the fourth embodiment. That is, the rim member 25 is composed of a horizontal portion 25a extending in the width direction along the bottom surface 20b of the sleeper body 20, and a vertical portion 25b extending upward along both longitudinal side surfaces 20c of the sleeper body 20 from both ends of the horizontal portion 25a. The horizontal section 25a and the vertical section 25b have a rectangular cross section.
[0097]
Then, the two edge members 25 are inserted and fixed from the bottom surface 20b side of the sleeper body 20 such that the side edges thereof are along the side edges of the bottom member 30b and the side member 30c of the wear-resistant member 30. I have. When the rim member 25 is attached in this manner, the horizontal part 25a and the vertical part 25b of the rim member 25 protrude from the surfaces of the bottom member 30b and the side member 30c of the wear-resistant member 30, as shown in FIG. Installed in state.
[0098]
Therefore, when the pillow 10 is laid on the roadbed, the side edges of the wear-resistant members 30b and 30c are protected by the rim material 25, thereby preventing the ballast from biting, preventing the wear-resistant member 30 from peeling off, and improving the durability. It becomes possible.
In addition, the rim member 25 forms a ridge to exhibit the same function as the misalignment prevention member 25 employed in the sleeper 4 of the fourth embodiment (see FIG. 4), and the pillow 10 moves the pillow 10 in the lateral direction of the roadbed. The displacement can be effectively suppressed.
[0099]
FIG. 16A is a perspective view showing the sleeper 11 according to the eleventh embodiment, FIGS. 16B and 16C are partially exploded perspective views of FIG. 16A, and FIG. 16D is a cross-sectional view of FIG. It is.
The sleeper 11 of the present embodiment is obtained by changing the shape and the mounting structure of the wear-resistant member 30 in the sleeper 10 of the tenth embodiment.
[0100]
That is, as shown in FIG. 16B, the wear-resistant member 30 is integrated by providing a cut-off portion 30d in the longitudinal direction on a bottom portion 30b formed in a rectangular cylindrical shape along the surface of the pillow body 20. (See FIG. 9).
Also, a groove 21 is formed on the upper surface 20a of the pillow main body 20, and a mounting structure is adopted in which the upper surface 30a of the wear-resistant member 30 is fitted into the groove 21 for mounting (FIGS. 11C and 11D). reference).
[0101]
Then, as shown in FIG. 16 (b), the pillow 11 is attached to the pillow main body 20 by attaching the wear-resistant member 30 thereto. It is manufactured by being attached and fixed along the side edges of 30.
As shown in FIG. 16D, the upper surface 30a of the abrasion-resistant member 30 is flush with the upper surface 20a of the pillow main body 20, and the separation portion 30d of the abrasion-resistant member 30 is connected to the bottom surface of the pillow main body 20. 20b.
[0102]
Therefore, according to the sleeper 11 of the present embodiment, similarly to the sleeper 10 of the tenth embodiment, when the sleeper 11 is laid on the roadbed, the side edges of the bottom surface 30b and the side surface 30c of the wear-resistant member 30 are edged. In addition to being protected by the material 25 to prevent the ballast from biting, the edge material 25 forms a ridge to effectively suppress the displacement of the sleeper 11 in the lateral direction of the roadbed.
[0103]
In the sleeper 11 according to the present embodiment, a plate-like rim may be joined to the bottom surface 20b of the sleeper body 20 where the cut-off portion 30d of the wear-resistant member 30 is located. According to this configuration, the cut-off portion 30d of the wear-resistant member 30 is protected from the ballast by the edge material, and peeling is prevented.
[0104]
FIG. 17A is a perspective view showing the sleeper 12 of the twelfth embodiment, FIGS. 17B and 17C are exploded perspective views of the assembling procedure of the sleeper 12 viewed from the bottom side, and FIG. It is the perspective view seen from.
The sleeper 12 according to the present embodiment is different from the sleeper 11 according to the eleventh embodiment in that the mounting structure of the wear-resistant member 30 is changed and the ridge 26 is formed at a portion of the cut-off portion 30 d of the wear-resistant member 30. It is.
[0105]
That is, the pillow 11 of the eleventh embodiment has a mounting structure in which the groove 21 is provided on the upper surface 20a of the pillow main body 20, but the pillow 12 of the present embodiment has a pillow as shown in FIG. In this configuration, a grooved portion is not provided in the main body 20, and the integrally formed wear-resistant member 30 is attached to the sleeper main body 20.
Further, a ridge 26 is formed by arranging a square member 26 between the horizontal portions 25a of the edge members 25, 25 attached along the side edges of the wear-resistant member 30. It is located at the site of the separation part 30 d of the sex member 30.
[0106]
According to the sleeper 12 of the present embodiment, the ridge 26 is formed at the center in the width direction of the bottom surface 20b of the sleeper main body 20 in the longitudinal direction, so that in addition to the effect of the sleeper 11 of the eleventh embodiment, Therefore, it is possible to suppress the displacement of the pillow 12 in the vertical direction of the roadbed.
In addition, since the square member 26 is attached to the portion of the cut-off portion 30d of the wear-resistant member 30, the side edge of the cut-off portion 30d is protected from ballast, the peeling of the wear-resistant member 30 is prevented, and the durability is improved.
[0107]
18A is a perspective view showing the sleeper 13 of the thirteenth embodiment, FIG. 18B is an exploded perspective view of the sleeper 13 as viewed from the bottom side, and FIG. 18C is a perspective view of the sleeper 13 as viewed from the bottom side. .
The sleeper 13 of the present embodiment is obtained by changing the position of the ridge extending in the longitudinal direction of the sleeper body 20 in the sleeper 12 of the twelfth embodiment.
That is, in the sleeper 12 of the twelfth embodiment, the ridge 26 is formed between the edge members 25 arranged adjacent to the side edges of the wear-resistant member 30.
On the other hand, in the sleeper 6 of the present embodiment, square members 27, 28 are arranged in a portion excluding between the edge members 25 arranged adjacent to each other in the longitudinal direction of the sleeper body 20, and the ridges 27, 28 are provided. Is formed.
[0108]
That is, the square member 27 is joined between the edge member 25 located outside the longitudinal direction of the sleeper body 20 and the longitudinal end of the sleeper body 20 to form a ridge 27, and the square member 28 is formed of the sleeper body 20. The ridges 28 are formed by being joined between the edge members 25 located inside the longitudinal direction.
[0109]
According to the sleeper 13 of the present embodiment, the length of the ridges 27 and 28 is longer than the length of the ridge 26 of the sleeper 12 of the twelfth embodiment. It can be suppressed.
In the present embodiment, no square member is provided at the cut-off portion 30d of the wear-resistant member 30. However, as in the twelfth embodiment, the square member 26 is joined to the cut-off portion 30d to form the wear-resistant member. It is possible to further improve the durability of the sleeper 30 and the effect of suppressing the displacement of the sleepers 13 in the vertical direction of the roadbed.
[0110]
FIG. 18D is a perspective view of a sleeper 13 ′ formed by adding a ridge 28 ′ to the sleeper 13 as viewed from the bottom side. That is, the pillow 13 ′ is provided between the edge members 25 arranged adjacent to the side edges of the abrasion-resistant member 30 and at the center in the width direction of the bottom surface 20 b of the pillow main body 20 in the longitudinal direction. Are joined to form a ridge 28 '.
According to the pillow 13 ', the ridges 27, 28', 28 are provided along the entire length of the pillow main body 20 in the longitudinal direction, and compared with the pillow 13 shown in FIG. It is possible to further improve the durability of the wear-resistant member 30 and the effect of preventing displacement of the wear-resistant member 30 in the vertical direction of the roadbed.
[0111]
19A is a perspective view showing the sleeper 14 of the fourteenth embodiment, FIG. 19B is an exploded perspective view of the sleeper 14 as viewed from the bottom side, and FIG. 19C is a perspective view of the sleeper 14 as viewed from the bottom side. .
The pillow 14 of the present embodiment is different from the pillow 10 of the tenth embodiment in that a plurality of square lugs are provided in the width direction of the pillow main body 20 at a portion of the bottom surface 20b of the pillow main body 20 where the wear-resistant member 30 is not attached. 29 are formed to form a plurality of ridges 29. In the present embodiment, the square member 29 has a smaller cross-sectional area than the horizontal portion 25a and the vertical portion 25b of the edge member 25.
[0112]
The square members 29 are respectively joined one by one to the outside of the edge member 25 near the longitudinal both ends of the sleeper body 20, and the gap between the adjacent edge members 25 near the longitudinal center part of the sleeper body 20 is set. Are joined together.
According to the sleeper 14 of the present embodiment, similarly to the sleeper 10, the durability of the wear-resistant member 30 is improved, and the ridge 29 can further suppress the positional shift of the sleeper 14 in the lateral direction of the roadbed. It becomes.
[0113]
As described above, the embodiments of the present invention have been described. However, the ridges 22 to 28 adopted for the sleepers of the second to sixth embodiments, and the edge material 25 adopted for the sleepers of the tenth to fourteenth embodiments, As for the ridges 26 to 28, similarly to the sleeper 1 of the first embodiment, the protrusion length from the surface of the sleeper body 20 is set to be substantially equal to the average particle diameter (50 mm) of the ballast laid on the roadbed. Made. Thereby, for the same reason as the sleeper 1 of the first embodiment, the ridge or the edge member can receive a stable drag from the ballast, and the displacement of the sleeper can be effectively prevented.
[0114]
Further, the pillow main body, the ridges, and the material of the rim used in the pillows 2 of the second to fourteenth embodiments are not particularly mentioned, but are manufactured using synthetic wood as in the pillows of the first embodiment. As a result, productivity and durability can be improved, and the weight can be reduced.
In addition, the sleeper of the present invention is not limited to synthetic wood, and can be made of concrete. In addition to durability and abrasion resistance, the sleeper can be a PC sleeper that effectively prevents displacement. it can.
[0115]
Next, a description will be given, with reference to FIG. 20, of the structure of the test sleeper and the test result of the lateral resistance of the track bed examined when determining the shape of the sleeper according to the embodiment of the present invention.
The dimensions of the standard sleeper 50 are, as shown in FIG. 20 (a), length (L) 2200 mm × width (W) 230 mm × height (H) 140 mm. Test pillows 51 to 57 changed as shown in (b) to (h) were prototyped, and the track bed lateral resistance was determined. The shapes of the test sleepers 51 to 57 are as follows.
[0116]
As shown in FIG. 20 (b), the cross section of the test sleeper 51 having a width w1 (120 mm) and a height h1 (40 mm) is substantially semicircular along the longitudinal direction at the center of the bottom surface of the standard sleeper 50. And the corner of the groove is curved with a radius R (40 mm).
As shown in FIG. 20C, the test sleeper 52 has a shape in which a groove having a width w2 (70 mm) and a height h2 (35 mm) is provided along the longitudinal direction at the center of the bottom surface of the standard sleeper 50. is there.
[0117]
As shown in FIG. 20 (d), the test sleeper 53 (the shape already published in the patent) has a length w3 (150 mm) and a height h3 on the bottom surface of both ends of the standard sleeper 50 over the entire length in the width direction. (40 mm) plate (packing) is attached.
As shown in FIG. 20 (e), the test sleeper 54 has a shape in which a square lumber having a width w4 (50 mm) and a height h4 (50 mm) is attached to the center of the bottom surface of the standard sleeper 50 along the longitudinal direction along the entire length. is there.
[0118]
As shown in FIG. 20 (f), the test sleeper 55 has a structure in which six U-shaped misalignment preventing members 55a extending from the bottom surface of the standard sleeper 50 to both longitudinal sides are attached. The displacement prevention member 55a is formed by connecting square members having a height h5 (50 mm) and a width w5 (50 mm) in a U-shape.
As shown in FIG. 20 (g), the test sleeper 56 has a shape in which partition walls 56a are provided at predetermined intervals in the grooves of the test sleeper 51.
As shown in FIG. 20 (h), the test sleeper 57 has a shape in which partition walls 57a are provided at predetermined intervals in grooves of the test sleeper 52.
[0119]
When measuring the lateral resistance of the test pillows 51 to 57, the weight is applied in the longitudinal direction (lateral direction of the trajectory) of the test pillows 51 to 57, and the displacement (position displacement) of the test pillows is 2 mm. The load at the time of becoming was defined as the roadbed lateral resistance. The results are as shown in Table 1.
[0120]
As shown in Table 1, the test pillows 51 and 52 having the groove on the bottom surface have an approximately 250 (kgf) lower than the track bed lateral resistance 308 (kgf) of the standard pillow 50. This is considered to be due to the fact that the body weight of the test sleepers 51 and 52 was reduced due to the provision of the grooves.
In the test sleepers 56 and 67 having the partition walls 56a and 57a provided in the grooves, the track bed lateral resistance increased to approximately 290 (kgf), but was lower than the standard sleeper 50.
[0121]
However, in the test sleeper 53, the cross-sectional area of the sleeper increases on the bottom side, so that the lateral resistance of the track bed becomes 427 (kgf), which is approximately 1.4 times as large as that of the standard sleeper 50.
In the test pillow 54, the resistance in the lateral direction of the track bed is 413 (kgf), which is approximately 1.35 times that of the standard pillow 50, and has the same effect as the test pillow 53. This is thought to be due to the fact that the cross section of the sleeper increases at the bottom portion where the pressure is large, and furthermore, by providing the convex body over the entire length in the longitudinal direction, the effect of preventing the displacement is large.
In the test sleeper 55, the resistance in the lateral direction of the track bed was 670 (kgf), which was approximately 2.2 times as large as that of the standard sleeper 50. This is considered to be due to the shape effect that the cross-sectional area of the sleeper increased approximately 1.95 times from the side surface to the bottom surface.
[0122]
[Table 1]
[0123]
【The invention's effect】
According to the sleeper of the present invention described in claims 1 to 4, displacement of the sleeper in the vertical direction of the track bed or in the horizontal direction of the track bed can be effectively prevented.
According to the fifth and sixth aspects of the present invention, it is possible to provide a sleeper in which the effect of preventing displacement is further improved by a simple configuration.
According to the present invention as set forth in claims 7 and 8, it is possible to effectively suppress the occurrence of friction and wear generated between the rail or the tie plate and the sleeper, or between the sleeper and the ballast, thereby improving durability. Can provide improved sleepers.
According to the present invention described in claims 9 to 13, it is possible to provide a sleeper that has an effect of improving the durability of the wear-resistant member and also preventing the displacement of the sleeper.
[Brief description of the drawings]
FIG. 1A is a perspective view showing a sleeper according to an embodiment of the present invention, and FIG. 1B is an exploded perspective view of FIG.
FIG. 2A is a perspective view showing a sleeper according to another embodiment of the present invention, and FIG. 2B is an exploded perspective view of FIG.
3A is a perspective view showing a sleeper according to another embodiment of the present invention, and FIG. 3B is an exploded perspective view of FIG.
4A is a perspective view showing a sleeper according to another embodiment of the present invention, and FIG. 4B is an exploded perspective view of FIG.
5A is a perspective view showing a sleeper according to another embodiment of the present invention, and FIG. 5B is an exploded perspective view of the sleeper of FIG.
FIG. 6A is a perspective view showing a sleeper according to another embodiment of the present invention, and FIG. 6B is an exploded perspective view of the sleeper of FIG.
7A is a perspective view showing a sleeper according to another embodiment of the present invention, and FIG. 7B is an exploded perspective view of FIG.
8A is a partially exploded perspective view of the sleeper shown in FIG. 7, and FIG. 8B is a perspective view of FIG.
FIGS. 9A to 9D are perspective views showing a shape of a wear-resistant member and a mounting method thereof.
FIGS. 10A and 10B are perspective views showing the shape of another wear-resistant member and a mounting method thereof.
11 (a) to 11 (h) are perspective views showing a mounting structure when a wear-resistant member is mounted on a sleeper.
FIG. 12A is a perspective view showing a sleeper according to another embodiment of the present invention.
13A is a partially exploded perspective view of the sleeper shown in FIG. 12, FIG. 13B is a partial perspective view of the sleeper shown in FIG. 12, and FIG. 13C is a side view of FIG.
14A is a perspective view showing a sleeper according to another embodiment of the present invention, FIG. 14B is a partially exploded perspective view of FIG. 14A, and FIG. 14C is a cross-sectional view of FIG. FIG. 4D is an enlarged view of the circle in FIG.
15A is a perspective view showing a sleeper according to another embodiment of the present invention, FIG. 15B is a partially exploded perspective view of FIG. 15A, and FIG. 15C is a cross-sectional view of FIG. FIG.
FIG. 16 (a) is a perspective view showing a sleeper according to another embodiment of the present invention, (b) and (c) are partially exploded perspective views of (a), and (d) is an A- view of (a). It is arrow A sectional drawing.
17A is a perspective view showing a sleeper according to another embodiment of the present invention, FIG. 17B is an exploded perspective view showing a state in which a wear-resistant member is attached to the sleeper of FIG. FIG. 3A is a partially exploded perspective view of the sleeper seen from the bottom, and FIG. 4D is a perspective view of the sleeper shown in FIG.
18A is a perspective view showing a sleeper according to another embodiment of the present invention, FIG. 18B is an exploded perspective view of the sleeper of FIG. FIG. 3D is a perspective view of the sleeper seen from the bottom side, as viewed from the bottom side. FIG. 4D is a perspective view of the sleeper obtained by further adding a ridge to the sleeper of FIG.
FIG. 19 (a) is a perspective view showing a sleeper according to still another embodiment of the present invention, (b) is an exploded perspective view of the sleeper of (a) viewed from the bottom side, and (c) is (a). It is the perspective view which looked at the sleeper from the bottom side.
20A is a front view and a side view of a standard sleeper, and FIGS. 20B to 20H are a front view and a side view of a test sleeper.
[Explanation of symbols]
1,2,3,4,5,6,7,8 pillow
9,10,11,12,13,14 Sleeper
20 sleepers (body)
20a Top of pillow (body)
20b Bottom of sleeper (body)
20c Longitudinal sides of sleeper (body)
21, 22, 23, 24, 25a, 25b ridge
26,27,28,28'29 ridge
25, 40, 41 Edge material
30, 32 wear-resistant members
