JP2000515452A

JP2000515452A - Rotatable grounding structure

Info

Publication number: JP2000515452A
Application number: JP09519231A
Authority: JP
Inventors: グレィミィ・アルフレッド・チャンドラー; グレゴリィ・リチャード・ヘイドン; ステファン・ハワード; ブライアン・フランク・マンガーノ
Original assignee: エアボスタイヤズピィーティーワイリミティッド
Priority date: 1995-11-20
Filing date: 1996-11-20
Publication date: 2000-11-21
Also published as: CN1089299C; EP0865368A4; CN1207708A; WO1997018959A1; EP0865368A1

Abstract

(57)【要約】タイヤなどの回転可能な地面接地構造体。タイヤは内面(１５)と相対する両側面(２３)からなる弾性変形可能体(１１)を有する。該体には多数の空洞(１１)が設けられ、該空洞は該体の各両側面上に設けられた第１組(３１)と第２組(３２)からなる。各空洞は該体の各側面(２３)に一端が開放しており、もう一端は閉鎖している。各側面上の第１組(３１)の空洞は内面(１５)から離れる方向で同じ側面上の第２組(３２)の空洞の外側に設けられる。各側面上の第１組(３１)の空洞(３３)は同じ側面上の第２組(３２)の空洞(３４)に対して回転方向にずれた配置となつている。該体の一方の側の第１組(３１)の空洞(３３)は該体のもう一方の側の第１組(３１)の空洞(３３)に対して回転方向にずれた配置となっており、該体の一方の側の第２組(３２)の空洞(３４)は該体のもう一方の側の第２組(３２)の空洞(３４)に対して回転方向にずれた配置となっている。この配置により、該体(１１)の各側面(２３)上の空洞(３３、３４)は回転方向にずれた状態となり、空洞(３３、３４)のいずれも回転方向と直交する方向で互いに一列に配置されない。 (57) [Summary] A rotatable ground contact structure such as a tire. The tire has an elastically deformable body (11) consisting of both sides (23) facing the inner surface (15). The body is provided with a number of cavities (11), the cavities comprising a first set (31) and a second set (32) provided on each side of the body. Each cavity is open at one end on each side (23) of the body and closed at the other end. The first set of cavities on each side is provided outside the second set of cavities on the same side in a direction away from the inner surface. The cavities (33) of the first set (31) on each side are rotationally offset from the cavities (34) of the second set (32) on the same side. The cavities (33) of the first set (31) on one side of the body are rotationally offset from the cavities (33) of the first set (31) on the other side of the body. The second set of cavities (34) on one side of the body are rotationally offset from the second set of cavities (34) on the other side of the body; Has become. With this arrangement, the cavities (33, 34) on each side (23) of the body (11) are shifted in the rotational direction, and all of the cavities (33, 34) are aligned with each other in a direction perpendicular to the rotational direction. Not placed in

Description

【発明の詳細な説明】発明の名称回転可能な地面接地構造体産業上の分野本発明は、地上接地面にクッション作用をもたらす回転可能な地面接地構造体に関する。例えば、地面接地構造体は車輪用タイヤ又は無端軌道用の地面接地構造体からなる。更に詳細に述べると、本発明は非空気式を特徴とするような地面接地構造体に関する。従来の技術本発明は、この明細書中で内容が引用されている国際出願ＰＣＴ／ＡＵ９５／００５１４号に記載のタイヤの改良品である。上記国際出願は、ホイールリムなどの回転可能な支持具と係合する内面を有する弾性変形可能体からなるタイヤ型の回転可能地面接地構造体を示している。環状体には弾性能を増すための多数の空洞が設けられている。該空洞は、周方向に間隔が開くように配置された第１組の空洞と、周方向に間隔が開くように配置された第２組の空洞からなる。該空洞は該体を横断状に延び、タイヤの反対側に通じている。第１組の空洞は内面から離れる方向で、第２組の外側に位置しており、第１組の各空洞は（回転方向と直交する方向で）第２組の各空洞と一列に並んでいる。この構造では、荷重の軸受けウェブを設置する硬部分は隣接する空洞間で規定される。そのような構造の欠点は、タイヤの両側面間を横断状に延びる比較的硬い部分と柔らかい部分が交互に現れることである。この硬い部分は該硬部分に相当し、柔らかい部分は空洞の部位に相当する。この交互の軟硬部は円滑な走行に貢献するものとならない。本発明は、走行の性能を向上させた地面接地構造体を提供するものである。発明の概要本発明は、内面及び相対する両側面を有する弾性変形可能体からなり、該体の両側面上には多数の空洞が設けられ、各空洞の一端は該体のそれぞれの側面上に開放され、もう一端は閉鎖されるか断面先細り形状となしてあり、該体の一方の側面上の空洞はもう一方の側面上の空洞に対して、回転方向にずれた配置となっている。そのような構造では、空洞は回転方向においてジグザグ配置となり、硬い部分と柔らかい部分の配置は上記国際出願で記載されたタイヤよりも安定した走行により貢献するものとなる。空洞は、該体の両側面上の第１組の空洞からなるが、該体の両側面上の第２組の空洞を設けてもよい。該第２組の空洞はそれぞれその一端は該体の各側面上に開放され、もう一端は閉鎖されるか変形断面部分からなる。各側面上の第１組の空洞は、内面から離れる方向で、同じ側面上の第２組の空洞の外側に設けられ、各側面上の第１組の空洞は、同じ側面上の第２組の空洞に対して回転方向にずれた配置となっている。一方の側面上の第１組の空洞は該体のもう一方の側面上の第１組の空洞に対して回転方向にずれた配置となっており、また一方の側面上の第２組の空洞は該体のもう一方の側面上の第２組の空洞に対して回転方向にずれた配置となっている。そのような構造では、該体の各側面上の空洞は回転方向に於いてジクザグ配置となっているため、該空洞は回転方向と直交する方向に於いて一つとして他の空洞と一列に並ぶことはない。このように空洞は分離した軟硬部を回避した、或いは少なくともその影響を抑えた状態で該体内に配置されるので、尚一層安定した走行を提供するものとなる。該体の各側面上の空洞はその外端は開放状態であるが、その内端は閉鎖状態とするのが好ましい。各空洞の内端はタイヤ中心の手前で終わるのが好ましい。そのような構造では、地面接地構造体には該体内に周方向に延びる中央ウェブが設けられる。該中央ウェブは、側面に隣接する外側部分より硬い構造の中央部分を地面接地構造体に形成する。これはタイヤには好ましい特徴である。中央ウェブが存在することで、地面接地構造体は操作中にしばしば受ける強度なねじれ圧に耐え得るものとなる。各組の空洞は、該構造体の回転方向に於いて間隔を有しており、各組の隣接する空洞の間隔は、回転方向に於ける空洞の最大幅とほぼ同じである。しかしながら、空洞とその間隔の相関寸法は、例えば、地面接地構造体の生産に用いられる異なるゴム化合物に適合する程度に変えることができる。空洞の断面寸法が空洞の間隔より短いものでは、放射状の荷重軸受けウェブを該体の各側面上の空洞間に形成してもよい。空洞はその断面形状が円形のものが好ましい。第１組の空洞の円形形状は、円弧の凹側が対向関係にある１組の離れた円弧とその円弧を連結する中間線からなる。２つの円弧が異なる湾曲半径を有するものでは、大きい円弧がタイヤの内側に設けられる。円弧間を連結する中間線は湾曲していてもよく、結果として空洞の断面形状が卵形のような閉鎖曲線となってもよい。各空洞は該体内でその長さ全体に亘って、縦方向で且つ実質上一定した整列状態にあるのが好ましい。空洞は回転方向と直交するように該体の軸方向に延びてもよい。一方、空洞或いは少なくとも空洞の一部は軸方向に傾斜した状態で、その結果回転方向に傾斜したものとなしてもよい。第２組の空洞は一般的に円形状断面をなしているが、例えば第１組の空洞の形状のように他の適当な断面形状をなしてもよい。地面接地構造体は一個体の構造体としてもよいし、或いは多数の地面接地セグメントからなして、それらを互いに組み合わせて地面接地構造組立品を形成してもよい。一個体の構造体からなる地面接地構造体は地面接地構造組立品よりも操作中の熱発生が低いという利点がある。これは一個体の構造体には、地面接地構造組立品に存在し地面接地構造体の回転動作中に摩擦されるものとなるセグメント間の接合点がないためである。本発明は又、他のセグメントと共に組み合わされて上記の地面接地構造体を形成する地面接地セグメントを提供するものである。本発明は更に、内面及び相対する両側面を有する弾性変形可能体からなり、該体には多数の空洞が設けられ、該空洞は該体の両側面上に設けられた第１組の空洞と第２組の空洞からなり、各空洞は一端が該体の各側面上に開放されており、もう一端は閉鎖しているか或いは断面先細り形状となしてあり、各側面上の第１組の空洞は内面から離れる方向で、同じ側面上の第２組の空洞の外側に設けられ、各側面上の第１組の空洞は同じ側面上の第２組の空洞に対して回転方向にずれた配置となっており、該体の一方の側面上の第１組の空洞は該体のもう一方の側面上の空洞に対して回転方向にずれた配置となっており、該体の一方の側面上の第２組の空洞は該体のもう一方の側面上の第２組の空洞に対して回転方向にずれた配置となっている回転可能な地面接地構造体を提供するものである。本発明は更に、内面及び相対する両側面を有する弾性変形可能な環状体からなり、該体には多数の空洞が設けられ、該空洞は該体の両側面上に設けられた第１組の空洞と第２組の空洞からなり、各空洞は一端が該体の各側面上に開放されており、もう一端は閉鎖しているか或いは断面先細り形状となしてあり、各側面上の第１組の空洞は内面から離れる方向で、同じ側面上の第２組の空洞の外側に放射状に設けられ、各側面上の第１組の空洞は同じ側面上の第２組の空洞に対して周方向にずれた配置となっており、該体の一方の側面上の第１組の空洞は該体のもう一方の側面上の第１組の空洞に対して周方向にずれた配置となっており、該体の一方の側面上の第２組の空洞は該体のもう一方の側面上の第２組の空洞に対して周方向にずれた配置となっているタイヤを提供するものである。図面の簡単な説明本発明は、以下の添付図面で示される幾つかの実施態様の説明を参照することにより、より理解されるものである。図１は、第１実施態様によるタイヤの斜視図であり、内部に設けられた空洞の詳細がわかるよう一部切り取って示す。図２は第１実施態様によるタイヤの部分断面図である。図３は、隠れた詳細部が背面側のタイヤの表面を表すために示された以外は、図１と同様である。図４は、タイヤの端面図である。図５は、図２の４−４線の横断面図である。図６は、回転動作中の一定荷重下でのタイヤの歪みを示すグラフである。図７は、前記国際出願に記載されたタイヤに関して図６と同様に示す。図８と９は、異なる空洞の配列をもつ他のタイヤに関して説明するために、図６と同様に示す。図１０は、第２実施態様によるタイヤの斜視図であり、内部に設けられた空洞の詳細がわかるよう一部切り取って示す。図１１は、第２実施態様によるタイヤの部分断面図である。図１２は、隠れた詳細部が背面側のタイヤの表面を表すために示された以外は、図１１と同様である。実施例図面に示されるそれぞれの実施態様は、元来フォークリフトに於けるような商用や工業用として使われる非空気式のタイヤからなる回転可能な地面接地構造体に関する。図１から５に於いて、第１実施態様によるタイヤはゴムのような弾性材料で形成された環状体１１からなる。環状体１１は適当な補強剤１２を組み合わせてもよい。環状体１１は、（図示されていない）ホイールリムのような回転可能な支持具と係合する内面１５を備えた放射構造の内端部１３と地面に接触する外面１９を含む放射構造の外端部１７からなる。タイヤの接地面の溝の形２１は地面と係合する外面１９に設けられる。１組の相対する側面壁２３は内端部１３と外端部１７との間にわたる。本実施態様に於いては、内端部１３は通常のスプリットリムタイヤのホイールリムと係合するよう構成される。多数の縦方向の空洞３０はその弾性能を高めてクッション性のある走行を提供するために環状体内に設けられる。該空洞は２組配列され、タイヤの各側面上に第１組の空洞３１と第２組の空洞３２が配置される。第１組の空洞３１は周方向に間隔を開けて配置された一連の空洞３３からなり、第２組の空洞３２は周方向に間隔を開けて配置された一連の空洞３４からなる。第２組３２の空洞３４は、図面に示すごとく、第１組３１の空洞３３の内側に放射状に配置される。それぞれの空洞３３，３４はその外端３５でタイヤのそれぞれの側面壁２３上に開放されており、タイヤに対して軸方向に該体を横断状に延びている。空洞３３，３４はそれぞれその内端３６で閉鎖されており、空洞の長さはタイヤの半分より短く、空洞の内端がタイヤの中心の手前で終わるものとなっている。この配列に於いて、タイヤの中心部分には環状体１１の周方向に延びる荷重軸受け中央ウェブ３７が設けられている。第１及び第２組の空洞３３，３４は円形状断面を呈する。更に詳しく述べると、第１組３１の各空洞３３はその断面形状が卵形の細長い閉鎖曲線３８を呈している。。各空洞３３の断面形状を規定する閉鎖曲線３８は該空洞の断面形状に於ける放射状の外端部と放射状の内端部を規定しているそれぞれ２つの円弧３９ａ，３９ｂと見なされる。２つの円弧３９ａ，３９ｂは、中間線３９ｃ，３９ｄによってつながれ、完全な閉鎖曲線となす。その際、該中間線３９ｃ，３９ｄは弓状となす。各空洞３３を形成する細長い閉鎖曲線３８はその長さ方向に中心をとる長軸を有する。閉鎖曲線３８は又、該長軸と交差し、該曲線の最大横軸寸法に相当するもう一つの軸をもつ。空洞３３はそれぞれ、より広い方の端がタイヤの放射状の内端側に配置されるようになされる。この配列は、タイヤの通常の荷重条件で歪む際に、空洞の断面形状に鋭角な角を形成させないという利点がある。確かに、卵形の空洞は通常の操作条件では次第に荷重されるにつれ、一般に円形状に歪む傾向がある。断面卵形状の各空洞３３と該空洞の位置は、該空洞の重心がタイヤの放射状の内端に向かって設けられた該端に隣接するように配列される。この配列では、卵形の長軸がタイヤの放射状方向に延びる。第２組３２の空洞３４は断面形状が一般的に円形を成している。各組の空洞３３，３４は図１及び図２に最もよく表されるように、タイヤの各側面上に周方向に間隔を開けて配置される。特に、第１組３１の空洞３３は、タイヤの周方向に於ける断面形状の最大寸法と同じ間隔を開けて配置される。すなわち、第１組３１にある隣接する空洞３３の間の間隔４３は、空洞の断面形状を規定する閉鎖曲線３８の最大横寸法に相当する。同様に、各第２組３２の空洞３４の間の間隔４５は円形状断面の直径にほぼ等しい。タイヤの各側面上にある第１組及び第２組の空洞３３，３４は、図１及び図２で最もよく表されるようにお互いに対して、周方向にずれている。これは、第１組３１の隣接する空洞３３の間の間隔４３が、タイヤの各側面上で第２組３２の空洞３４に対して放射線状に並んでいることから明らかである。同様に、第２組３２の隣接する空洞３４間の間隔４５は、第１組３１の空洞３３に対して放射線状に配置している。更に、タイヤの一方の側面上にある第１組３１の空洞３３は、図２に見られるように、タイヤのもう一方の側面上の対応する空洞３３に対して、周方向にずれている。同様に、タイヤの各側面上にある空洞のうち第２組３２の空洞３４はそれぞれ、タイヤのもう一方の側面上の対応する空洞３４に対して周方向にずれている（ジグザグ配置となしてある）。タイヤの各側面上の空洞３３，３４をずらし、又、タイヤの反対側の対応する空洞をずらした状態では、タイヤの両側面上にある空洞３３，３４はどれ一つタイヤのもう一方の側面上にある空洞に対して放射線状に配置していない。更に、環状体１１にはその放射状の内端部とその外端部の間で中央ウェブ３１から離れて放射状に延びる荷重軸受けウェブはない。この形態は次の点で特に利点がある。即ち、タイヤが回転する際、タイヤには過度の歪みがなく、そのため規則的な走行を提供できるものとなる。このことは図面の図５から８を参照すればより良く理解できる。図５は荷重状態で滑らかな表面上を回転する際の実施態様によるタイヤの歪みの変動の大きさを示す。図面より、歪みが比較的高頻度で生じ、その大きさは比較的小規模であることがわかる。確かに、歪みの変動の大きさは荷重状態でタイヤの総歪みのおよそ２．５％である。該実施態様に係るタイヤによる走行を前記の国際出願ＰＣＴ／ＡＵ９５／００５１４に記載のタイヤがによる走行と図６を参照して比較する。そのようなタイヤ（模式図状に示される）では、第１組の空洞Ａは第２組の空洞Ｂと放射状に一列に並び、且つ、放射状に広がる荷重軸受けウェブＣは該空洞の間に規定される。該空洞Ａ及びＢはタイヤを貫通し、その反対側上に開放している。荷重軸受けウェブＣに相当するタイヤの硬部分にはほとんど歪みはないが、該空洞Ａ及びＢがある部分では図６に見られるようにかなりの歪みがある。確かに、歪みの変動の大きさは荷重状態で総歪みのおよそ１０％である。従って、タイヤは極めて不規則な走行をすることになる。中空部Ａ及びＢはタイヤ本体を貫通しているが、それらを周方向にずらしてやることで走行は幾分改良される。この配列は図７に示されるが、それによれば歪みの変動の大きさは多少規則的ではあるが、本実施態様に係るタイヤ程規則的ではないことが明らかである。図７に於ける歪みの変動の大きさは荷重状態で総歪みのおよそ７．５％である。該グラフは２つのピーク、即ち空洞Ａによる大きなピークと空洞Ｂによる小さなピークを示す。空洞ＡおよびＢをその内端を閉鎖してタイヤの反対側で一列に並べることによって、走行は更に改良される。この配列では中央荷重軸受けウェブができる。図８に於ける歪みの変動の大きさは荷重状態で総歪みのおよそ５％である。図５に示される本実施態様のタイヤの歪みと図８に於けるタイヤの歪みを比較すると、空洞が周方向にずれるように空洞をタイヤの反対側でずらしたことによる利点は明らかである。本実施態様のタイヤは図６，７及び８に示されたタイヤよりも全般的に剛構造である。この剛性度の増大はタイヤ内の空洞の配列によるものである。この増大された剛性度は、タイヤ構成用の軟性ゴムを使用することで相殺することができる。これは、弾性ヒステレリスがほとんどないという利点を有するので、熱をほとんど発生せずタイヤの寿命も長くなる。上記により、第１の実施態様が比較的滑らかな走行を提供するため、空気タイヤがパンクしにくいという利点を有することが明らかである。該タイヤには前記述の国際出願に記載されたタイヤよりもゴムの使用を少なくしてもよい。代わりに硬質ゴムが使用される場合、空洞の配列により増大される剛性を相殺するために、該空洞は大きくしてもよい。更に、本タイヤは、中央ウェブの存在による耐久性を向上させて、操作中に受けやすい強いるねじれ圧にも耐え得るものとなる。図１０，１１，１２に、第２実施態様に係るタイヤ１１を示す。該タイヤはタイヤの各側面上に空洞の一組３１だけがある以外は第１実施態様と同様であり、これは第１実施態様のタイヤにある空洞の第１組３１に相当する。この第２実施態様では、空洞の該組３１はタイヤの各側面上の周方向に間隔を開けて配置された一連の空洞３３からなる。タイヤの一方の側面上にある空洞３３は参照数字３３ａでそれぞれ示され、タイヤのもう一方の側面上にある空洞３３は参照数字３３ｂでそれぞれ示される。タイヤの一方の側面上にある該空洞３３ａは、図１０で最もよく示されるように、もう一方の側面上にある空洞３３ｂに対して周方向にずれている（ジグザグは位置となっている）。第１及び第２実施態様では、空洞３３は卵形をなす。空洞３３（及び第１実施態様にある空洞３４）はもちろん他の適当な形をなしてもよい。例えば、各空洞３３の円弧３９ａ，３９ｂを連結する中間線３９ｃ，３９ｄは直線或いは、代わりに第１実施態様に記載された弓状のような適当な形をなしてもよい。更に、二つの円弧３９ａ，３９ｂは湾曲半径が等しくない図面で示される配合の代わりに、湾曲半径を等しいものと成してもよい。又更に各空洞３３の円弧の一つの湾曲半径を残りの円弧の湾曲半径に対して、実施態様に示された場合のようにかなり大きくする代わりに、極僅かだけ大きくなしてもよい。本発明の範囲は実施態様に記載された範囲に限定されるものではない。BACKGROUND OF THE INVENTION Field of the name rotatable ground-contacting structure Industry The present invention relates rotatable ground-contacting structure that provides cushioning to the ground contact surface. For example, the ground contact structure may be a tire for a wheel or a ground contact structure for an endless track. More particularly, the present invention relates to a ground contact structure, such as a non-pneumatic feature. BACKGROUND OF THE INVENTION The present invention is an improvement of the tire described in International Application No. PCT / AU95 / 00514, the contents of which are incorporated herein. The above international application shows a tire-type rotatable ground contact structure comprising an elastically deformable body having an inner surface that engages a rotatable support such as a wheel rim. The annular body is provided with a number of cavities for increasing the elasticity. The cavities comprise a first set of cavities circumferentially spaced and a second set of cavities circumferentially spaced. The cavity extends transversely through the body and leads to the opposite side of the tire. The first set of cavities is located outside of the second set, away from the inner surface, and each first set of cavities is aligned with the second set of cavities (in a direction orthogonal to the direction of rotation). I have. In this configuration, the rigid part on which the load bearing web is located is defined between adjacent cavities. A disadvantage of such a construction is that relatively hard and soft portions alternate between the two sides of the tire. The hard portion corresponds to the hard portion, and the soft portion corresponds to the hollow portion. This alternate soft portion does not contribute to smooth running. The present invention provides a ground contact structure with improved running performance. SUMMARY OF THE INVENTION The present invention comprises an elastically deformable body having an inner surface and opposing sides, wherein a number of cavities are provided on both sides of the body, one end of each cavity being provided on a respective side of the body. It is open and the other end is closed or tapered in cross section, and the cavity on one side of the body is rotationally offset from the cavity on the other side. In such a configuration, the cavities are in a zigzag arrangement in the direction of rotation, and the arrangement of the hard and soft parts contributes to a more stable running than the tire described in the international application. The cavity comprises a first set of cavities on both sides of the body, but a second set of cavities on both sides of the body may be provided. The second set of cavities each has one end open on each side of the body and the other end closed or comprises a deformed cross-section. A first set of cavities on each side is provided outside of a second set of cavities on the same side in a direction away from the inner surface, and a first set of cavities on each side is a second set of cavities on the same side. Are arranged in the rotational direction with respect to the cavity. The first set of cavities on one side is rotationally offset from the first set of cavities on the other side of the body, and the second set of cavities on one side. Are rotationally offset from the second set of cavities on the other side of the body. In such a configuration, the cavities on each side of the body are zigzag in the direction of rotation so that the cavities line up with the other cavities as one in the direction perpendicular to the direction of rotation. Never. In this way, the cavity is disposed inside the body while avoiding the separated soft and hard parts, or at least suppressing the influence thereof, thereby providing a still more stable running. The cavities on each side of the body are open at the outer end, but preferably closed at the inner end. The inner end of each cavity preferably ends short of the center of the tire. In such a construction, the ground contact structure is provided with a central web extending circumferentially into the body. The central web forms a central portion of the structure that is stiffer than the outer portion adjacent the side to the ground contact structure. This is a desirable feature for tires. The presence of the central web allows the ground contact structure to withstand the high torsional pressures often experienced during operation. Each set of cavities has a spacing in the direction of rotation of the structure, and the spacing between adjacent cavities of each set is about the same as the maximum width of the cavities in the direction of rotation. However, the correlated dimensions of the cavities and their spacing can be varied, for example, to suit different rubber compounds used in the production of ground contact structures. If the cross-sectional dimensions of the cavities are less than the spacing between the cavities, radial load bearing webs may be formed between the cavities on each side of the body. The cavity preferably has a circular cross section. The circular shape of the first set of cavities consists of a set of distant arcs with the concave sides of the arcs facing each other and an intermediate line connecting the arcs. Where the two arcs have different radii of curvature, a large arc is provided inside the tire. The intermediate line connecting the arcs may be curved, so that the cross-sectional shape of the cavity may be an oval-shaped closed curve. Each cavity is preferably in a longitudinal and substantially constant alignment throughout its length within the body. The cavity may extend in the axial direction of the body orthogonal to the direction of rotation. On the other hand, the cavity or at least a part of the cavity may be inclined in the axial direction, so that it is inclined in the rotation direction. The second set of cavities generally has a circular cross-section, but may have any other suitable cross-sectional shape, for example, the shape of the first set of cavities. The ground contact structure may be a single structure, or may be made up of multiple ground contact segments, which are combined together to form a ground contact structure assembly. A single-structure ground contact structure has the advantage of lower heat generation during operation than a ground contact structure assembly. This is because a single structure does not have any junctions between the segments that are present in the ground contact structure assembly and will be rubbed during rotation of the ground contact structure. The present invention also provides a ground contact segment that is combined with other segments to form the above ground contact structure. The invention further comprises an elastically deformable body having an inner surface and opposing sides, wherein the body is provided with a plurality of cavities, the cavities comprising a first set of cavities provided on both sides of the body. A second set of cavities, each cavity being open at one end on each side of the body and the other end being closed or tapered in cross section, and a first set of cavities on each side. Is located away from the inner surface and outside the second set of cavities on the same side, the first set of cavities on each side being rotationally offset with respect to the second set of cavities on the same side. Wherein the first set of cavities on one side of the body is rotationally offset with respect to the cavities on the other side of the body; Of the second set of cavities are rotationally offset from the second set of cavities on the other side of the body. It is to provide a rolling possible ground ground structure. The invention further comprises an elastically deformable annular body having an inner surface and opposing sides, wherein the body is provided with a plurality of cavities, the cavities being a first set of cavities provided on both sides of the body. A cavity and a second set of cavities, each cavity being open at one end on each side of the body and the other end closed or tapered in cross-section; Cavities are radially provided outside the second set of cavities on the same side in a direction away from the inner surface, and the first set of cavities on each side are circumferentially relative to the second set of cavities on the same side. A first set of cavities on one side of the body are circumferentially offset from a first set of cavities on the other side of the body. , A second set of cavities on one side of the body is circumferentially offset from a second set of cavities on the other side of the body. This is to provide the tires that have been installed. BRIEF DESCRIPTION OF THE DRAWINGS The invention can be better understood with reference to the following description of several embodiments, illustrated in the accompanying drawings. FIG. 1 is a perspective view of a tire according to a first embodiment, partially cut away to show details of a cavity provided therein. FIG. 2 is a partial sectional view of the tire according to the first embodiment. FIG. 3 is similar to FIG. 1 except that the hidden details are shown to represent the rear tire surface. FIG. 4 is an end view of the tire. FIG. 5 is a cross-sectional view taken along line 4-4 in FIG. FIG. 6 is a graph showing the strain of the tire under a constant load during the rotation operation. FIG. 7 shows the tire described in the international application in the same manner as FIG. FIGS. 8 and 9 are shown similarly to FIG. 6 to describe another tire having a different arrangement of cavities. FIG. 10 is a perspective view of a tire according to a second embodiment, partially cut away to show details of a cavity provided therein. FIG. 11 is a partial sectional view of a tire according to the second embodiment. FIG. 12 is similar to FIG. 11 except that the hidden details are shown to represent the rear tire surface. Each of the embodiments shown in the Examples drawings relates rotatable ground-contacting structure consisting of a tire of a non-pneumatic used originally as commercial and industrial, as in the forklift. 1 to 5, the tire according to the first embodiment comprises an annular body 11 formed of an elastic material such as rubber. The annular body 11 may be combined with an appropriate reinforcing agent 12. The annulus 11 has an outer end 13 that includes an inner end 13 of the radiating structure with an inner surface 15 that engages a rotatable support such as a wheel rim (not shown) and an outer surface 19 that contacts the ground. It consists of an end 17. A groove 21 in the tire tread is provided on the outer surface 19 which engages the ground. A pair of opposing side walls 23 extend between the inner end 13 and the outer end 17. In this embodiment, the inner end 13 is configured to engage a wheel rim of a conventional split rim tire. A number of longitudinal cavities 30 are provided in the annulus to enhance their resilience and provide cushioned travel. The cavities are arranged in two sets, with a first set of cavities 31 and a second set of cavities 32 on each side of the tire. The first set of cavities 31 comprises a series of circumferentially spaced cavities 33 and the second set of cavities 32 comprises a series of circumferentially spaced cavities 34. The cavities 34 of the second set 32 are arranged radially inside the cavities 33 of the first set 31 as shown in the drawing. Each cavity 33, 34 is open at its outer end 35 on a respective side wall 23 of the tire and extends axially across the body with respect to the tire. The cavities 33, 34 are each closed at its inner end 36, the length of the cavities being shorter than half of the tire, with the inner end of the cavity ending short of the center of the tire. In this arrangement, a central portion of the tire is provided with a load bearing central web 37 extending in the circumferential direction of the annular body 11. The first and second sets of cavities 33, 34 have a circular cross section. More specifically, each cavity 33 of the first set 31 has an elongated closed curve 38 having an oval cross section. . The closed curve 38 defining the cross-sectional shape of each cavity 33 can be considered as two arcs 39a, 39b respectively defining a radial outer end and a radial inner end in the cross-sectional shape of the cavity. The two arcs 39a, 39b are connected by the middle lines 39c, 39d to form a complete closed curve. At this time, the intermediate lines 39c and 39d are formed in an arc shape. The elongate closure curve 38 forming each cavity 33 has a major axis centered in its length. Closure curve 38 also has another axis that intersects the major axis and corresponds to the largest transverse dimension of the curve. Each of the cavities 33 is adapted such that the wider end is located on the radial inner end side of the tire. This arrangement has the advantage that no sharp corners are formed in the cross-sectional shape of the cavity when the tire is distorted under normal load conditions. Indeed, oval cavities generally tend to distort into a circular shape as they are progressively loaded under normal operating conditions. The cavities 33 having an oval cross section and the locations of the cavities are arranged such that the center of gravity of the cavities is adjacent to the end provided toward the radially inner end of the tire. In this arrangement, the long axis of the oval extends in the radial direction of the tire. The cavities 34 of the second set 32 have a generally circular cross section. Each set of cavities 33, 34 is circumferentially spaced on each side of the tire, as best seen in FIGS. In particular, the cavities 33 of the first set 31 are arranged at the same interval as the maximum dimension of the cross-sectional shape in the circumferential direction of the tire. That is, the spacing 43 between adjacent cavities 33 in the first set 31 corresponds to the maximum lateral dimension of the closed curve 38 that defines the cross-sectional shape of the cavities. Similarly, the spacing 45 between the cavities 34 of each second set 32 is approximately equal to the diameter of the circular cross section. The first and second sets of cavities 33, 34 on each side of the tire are circumferentially offset with respect to one another, as best illustrated in FIGS. This is evident from the fact that the spacing 43 between adjacent cavities 33 of the first set 31 is radially aligned with the cavities 34 of the second set 32 on each side of the tire. Similarly, the spacing 45 between adjacent cavities 34 of the second set 32 is radially arranged with respect to the cavities 33 of the first set 31. Further, the cavities 33 of the first set 31 on one side of the tire are circumferentially offset from the corresponding cavities 33 on the other side of the tire, as seen in FIG. Similarly, each of the cavities 34 of the second set 32 of the cavities on each side of the tire is circumferentially offset with respect to the corresponding cavities 34 on the other side of the tire (in a zigzag arrangement). is there). With the cavities 33, 34 on each side of the tire offset and the corresponding cavities on the opposite side of the tire offset, any one of the cavities 33, 34 on both sides of the tire will have one of the other sides of the tire. Not radially arranged with respect to the cavity above. Furthermore, the annular body 11 does not have a load bearing web extending radially away from the central web 31 between its radial inner end and its outer end. This configuration has particular advantages in the following points. That is, when the tire rotates, the tire does not have excessive distortion, so that regular running can be provided. This can be better understood with reference to FIGS. 5 to 8 of the drawings. FIG. 5 shows the magnitude of tire strain variation according to an embodiment when rolling over a smooth surface under load. From the drawing, it can be seen that the distortion occurs relatively frequently and the size is relatively small. Indeed, the magnitude of the strain variation is approximately 2.5% of the tire's total strain under load. The running with the tire according to this embodiment is compared with the running with the tire described in the international application PCT / AU95 / 00514 with reference to FIG. In such a tire (shown schematically), a first set of cavities A is radially aligned with a second set of cavities B, and a radially extending load bearing web C is defined between the cavities. Is done. The cavities A and B pass through the tire and open on the other side. The hard portion of the tire corresponding to the load bearing web C has little distortion, but where there are cavities A and B, there is considerable distortion as seen in FIG. Indeed, the magnitude of the strain variation is approximately 10% of the total strain under load. Thus, the tire will travel very irregularly. Although the hollow portions A and B penetrate the tire main body, their running is somewhat improved by shifting them in the circumferential direction. This arrangement is shown in FIG. 7, which shows that the magnitude of the strain variation is somewhat regular, but not as regular as the tire according to this embodiment. The magnitude of the strain variation in FIG. 7 is approximately 7.5% of the total strain under load. The graph shows two peaks, a large peak due to cavity A and a small peak due to cavity B. Running is further improved by lining the cavities A and B with their inner ends closed and on the opposite side of the tire. This arrangement results in a central load bearing web. The magnitude of the variation of the strain in FIG. 8 is approximately 5% of the total strain under the load condition. Comparing the tire distortion of this embodiment shown in FIG. 5 with the tire distortion in FIG. 8, the advantage of shifting the cavity on the opposite side of the tire so that the cavity is shifted in the circumferential direction is clear. The tire of this embodiment has a generally more rigid structure than the tire shown in FIGS. This increase in stiffness is due to the arrangement of cavities in the tire. This increased stiffness can be offset by using soft rubber for tire construction. This has the advantage of having very little elastic hysteresis, so that it generates little heat and extends the life of the tire. From the above, it is clear that the first embodiment has the advantage that the pneumatic tire is less likely to puncture because it provides a relatively smooth running. The tires may use less rubber than the tires described in the aforementioned international application. If a hard rubber is used instead, the cavity may be large to offset the increased stiffness due to the arrangement of the cavity. Furthermore, the present tire has improved durability due to the presence of the central web, and can withstand the torsional pressure that is likely to be experienced during operation. FIGS. 10, 11, and 12 show a tire 11 according to the second embodiment. The tire is similar to the first embodiment except that there is only one set of cavities 31 on each side of the tire, which corresponds to the first set of cavities 31 in the tire of the first embodiment. In this second embodiment, the set of cavities 31 comprises a series of circumferentially spaced cavities 33 on each side of the tire. The cavities 33 on one side of the tire are designated by reference numeral 33a, respectively, and the cavities 33 on the other side of the tire are designated by reference numeral 33b, respectively. The cavity 33a on one side of the tire is circumferentially offset from the cavity 33b on the other side (the zigzag is in position), as best shown in FIG. . In the first and second embodiments, the cavity 33 has an oval shape. The cavity 33 (and the cavity 34 in the first embodiment) may of course have any other suitable shape. For example, the intermediate lines 39c, 39d connecting the arcs 39a, 39b of each cavity 33 may be straight or alternatively have a suitable shape, such as the bow described in the first embodiment. Further, the two arcs 39a, 39b may have equal radii of curvature instead of the blend shown in the figures where the radii of curvature are not equal. Still further, instead of making the radius of curvature of one of the arcs of each cavity 33 larger than the radius of curvature of the remaining arcs, as shown in the embodiment, it may be made only slightly larger. The scope of the present invention is not limited to the scope described in the embodiment.

───────────────────────────────────────────────────── フロントページの続き (31)優先権主張番号ＰＮ８５３６ (32)優先日平成８年３月７日(1996．3．7) (33)優先権主張国オーストラリア（ＡＵ） (81)指定国ＥＰ(ＡＴ，ＢＥ，ＣＨ，ＤＥ，ＤＫ，ＥＳ，ＦＩ，ＦＲ，ＧＢ，ＧＲ，ＩＥ，ＩＴ，ＬＵ，ＭＣ，ＮＬ，ＰＴ，ＳＥ)，ＯＡ(ＢＦ，ＢＪ，ＣＦ，ＣＧ，ＣＩ，ＣＭ，ＧＡ，ＧＮ，ＭＬ，ＭＲ，ＮＥ，ＳＮ，ＴＤ，ＴＧ)，ＡＰ(ＫＥ，ＬＳ，ＭＷ，ＳＤ，ＳＺ，ＵＧ)，ＥＡ(ＡＭ，ＡＺ，ＢＹ，ＫＧ，ＫＺ，ＭＤ，ＲＵ，ＴＪ，ＴＭ)，ＡＬ，ＡＭ，ＡＴ，ＡＵ，ＡＺ，ＢＡ，ＢＢ，ＢＧ，ＢＲ，ＢＹ，ＣＡ，ＣＨ，ＣＮ，ＣＵ，ＣＺ，ＤＥ，ＤＫ，ＥＥ，ＥＳ，ＦＩ，ＧＢ，ＧＥ，ＨＵ，ＩＬ，ＩＳ，ＪＰ，ＫＥ，ＫＧ，ＫＰ，ＫＲ，ＫＺ，ＬＣ，ＬＫ，ＬＲ，ＬＳ，ＬＴ，ＬＵ，ＬＶ，ＭＤ，ＭＧ，ＭＫ，ＭＮ，ＭＷ，ＭＸ，ＮＯ，ＮＺ，ＰＬ，ＰＴ，ＲＯ，ＲＵ，ＳＤ，ＳＥ，ＳＧ，ＳＩ，ＳＫ，ＴＪ，ＴＭ，ＴＲ，ＴＴ，ＵＡ，ＵＧ，ＵＳ，ＵＺ，ＶＮ (72)発明者グレゴリィ・リチャード・ヘイドンオーストラリア国、ウエスタンオーストラリア州、ソレント、ビュークレストウェイ 19 (72)発明者ステファン・ハワードオーストラリア国、ウエスタンオーストラリア州、ウェンブレイ、バレットストリート９ (72)発明者ブライアン・フランク・マンガーノオーストラリア国、ウエスタンオーストラリア州、クローリイ、クックストリート 26、ユニット１────────────────────────────────────────────────── ─── Continuation of front page (31) Priority number PN8536 (32) Priority Date March 7, 1996 (1996.3.7) (33) Countries claiming priority Australia (AU) (81) Designated countries EP (AT, BE, CH, DE, DK, ES, FI, FR, GB, GR, IE, IT, L U, MC, NL, PT, SE), OA (BF, BJ, CF) , CG, CI, CM, GA, GN, ML, MR, NE, SN, TD, TG), AP (KE, LS, MW, SD, S Z, UG), EA (AM, AZ, BY, KG, KZ, MD , RU, TJ, TM), AL, AM, AT, AU, AZ , BA, BB, BG, BR, BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, G E, HU, IL, IS, JP, KE, KG, KP, KR , KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ, P L, PT, RO, RU, SD, SE, SG, SI, SK , TJ, TM, TR, TT, UA, UG, US, UZ, VN (72) Inventor Gregory Richard Haydon Western Australia, Australia View Crestway, Sorrento, Province of Leah 19 (72) Inventor Stephen Howard Western Australia, Australia Leah, Wembley, Bullet Story To 9 (72) Inventor Brian Frank Mangano Western Australia, Australia Leah, Crawley, Cook Street 26, unit 1

Claims

[Claims] 1. An elastically deformable body having an inner surface and opposing sides, each side of the body being There are a number of cavities on the surface, one end of each cavity on each side of the body It is open and the other end is closed or tapered in cross section. The cavity on one side is offset from the other side in the rotational direction. A rotatable ground contact structure, characterized in that: 2. In a rotatable ground contact structure as set forth in claim 1, the cavity is defined as Consisting of a first set of cavities provided on each side of the body, on each side of the body A second set of cavities is provided, each second set of cavities on each side of the body. One end is open and the other end is closed or tapered in cross section. And the first set of cavities on each side is spaced apart from the inner surface by a first set of cavities on the same side. Outside the two sets of cavities, the first set of cavities on each side is the second set of cavities on the same side. Rotationally offset relative to the set of cavities, on one side of the body Of the first set of cavities are rotationally oriented relative to the first set of cavities on the other side of the body. And a second set of cavities on one side of the body Rotationally displaced relative to the second set of cavities on the other side It is characterized by the following. 3. A rotatable ground contact structure as claimed in claim 1 or 2, Make sure that the cavity on each side is open on each side at the outer end and closed at the inner end. Features. 4. In the rotatable ground contact structure described in claim 3, each of the cavities is The ends are characterized by ending shortly before the center of the body. 5. A rotatable ground contact structure as claimed in any of the preceding claims. The cavities of each set are spaced apart in the direction of rotation of the structure, The spacing between adjacent cavities should be about the same as the largest dimension of the cavity in the direction of rotation It is characterized by the following. 6. A rotatable ground contact structure as claimed in any of the preceding claims. The cavity has a circular cross section. 7. In a rotatable ground contact structure as set forth in claim 6, a first set of empty The sinus is characterized by an oval cross section. 8. In a rotatable ground contact structure as set forth in claim 7, each cavity is an egg. Characterized in that the large end of the shape is arranged towards the inner surface of the body I do. 9. In a rotatable ground contact structure as claimed in claim 6, 7, or 8 Each section of the first set of cavities is a set of spaced arcs and an intermediate line connecting the arcs And the concave portions of the arc are in an opposite relationship. 10. In a rotatable ground contact structure as set forth in claim 9, the arcs are different. It has a characteristic bending radius. 11. In a rotatable ground contact structure as claimed in claim 9 or 10, The line connecting the arcs is curved. 12. In a rotatable ground contact structure as claimed in claim 9 or 10, The line connecting the arcs is substantially a straight line. 13. In a rotatable ground contact structure as set forth in claim 6, a second set of empty The sinus is characterized by having a substantially circular cross section. 14． A rotatable ground contact structure as claimed in any of the preceding claims. , Each cavity is longitudinally and substantially constant in its body over its length range It is characterized by being installed in. 15. A rotatable ground contact structure as claimed in any of the preceding claims. The cavity extends axially into the body and is orthogonal to the direction of rotation. 16. A rotatable ground contact structure as claimed in any of claims 1-14. And the cavity is inclined with respect to the rotation direction. 17． A rotatable ground contact structure as claimed in any of the preceding claims. , Characterized in that the body is annular. 18. A rotatable ground contact structure as claimed in any of the preceding claims. , Wherein the structure is a single solid structure. 19. A rotatable ground contact structure as claimed in any one of claims 1 to 17 The structure consists of a number of ground contact segments, which are assembled It is characterized by forming a ground contact structure complex. 20. Assembled with the other segments to form a ground contact as claimed in claim 19. A ground contact segment capable of forming a ground structure. 21. It consists of an elastically deformable annular body having both sides facing the inner surface, A number of cavities are provided, the cavities being a first set of cavities provided on each side of the body. A cavity and a second set of cavities, each cavity being open at one end on each side of the body. The other end is closed or tapered in cross section, on each side Of the first set of cavities are in a direction away from the inner surface and outside of the second set of cavities on the same side. Radially provided, a first set of cavities on each side is a second set of cavities on the same side And a first set on one side of the body. The cavities are circumferentially offset with respect to the first set of cavities on the other side of the body And the second set of cavities on one side of the body is on the other side of the body. It is characterized in that it is displaced circumferentially with respect to the second set of cavities above. Tires. 22. A rotatable ground contact structure substantially as herein described with the accompanying drawings.