JP4258683B2

JP4258683B2 - Caster swivel

Info

Publication number: JP4258683B2
Application number: JP25839698A
Authority: JP
Inventors: 宏和酒向; 禎久高野
Original assignee: Shishiai KK
Current assignee: Shishiai KK
Priority date: 1998-09-11
Filing date: 1998-09-11
Publication date: 2009-04-30
Anticipated expiration: 2018-09-11
Also published as: JP2000085308A

Description

【０００１】
【発明の属する技術分野】
本発明は、キャスター旋回装置に関し、詳しくは水に晒されやすい環境下でも使用できる簡単な構成で防錆性及び旋回性に優れるキャスター旋回装置に関するもので、さらに例えばボートキャスターのようにキャスター旋回装置を水中で作動させても防錆性を維持できるキャスター旋回装置に関する。
【０００２】
【従来の技術】
キャスターは台車やワゴン、家具等に多用されている。ところで、キャスターが使用されるものの中には、水に晒され易い環境で使用されるものがあり、ボートキャスターや冷凍室を出入りする台車等が例示される。そして、このような状況下で継続して使用し続ければ、キャスター旋回装置内に水が浸入して錆が発生し、旋回性に障害が生じるばかりか、錆が隆起してくると、ついには旋回できなくなり耐久性を著しく低下させることがあった。
【０００３】
そこで、従来より防水措置を講じたキャスター旋回装置が提供されている。
【０００４】
例えば、固定板と軸受板とを近接させ、この固定板の下部円形部の外周縁と前記軸受板の上部円形部の外周縁とを円弧状に形成し、両外周縁間に生じる空間部に、断面を円形にしたゴム製Ｏリングを圧接させたキャスターホイールが提供されている（特開平６−１４３９０７号参照）。しかし、このキャスターホイールは、ゴム製のＯリングが固定板と軸受板の両者に圧接されるものであるため、摩擦抵抗が大きくなりキャスターの円滑な旋回を妨げる虞があった。
【０００５】
また、車輪を軸架する股金具の水平係合板の外周縁と台板の突縁との間にシール材を液密に介在させるキャスターが提供されている（実公昭５６−２０２４２号参照）。しかし、このキャスターも、シール材で股金具と台板の両者を液密に介在させるものであるため、上記と同様に摩擦抵抗が大きくなりキャスターの円滑な旋回を妨げる虞があった。
【０００６】
また、上記従来の防水性のキャスター旋回装置は、例えば冷凍室を出入りする台車等水気の多いところで使用されるものであり、ボートキャスターのようにキャスター旋回装置自体を水中で作動させるような過酷な条件下での使用には不向きであった。
【０００７】
【発明が解決しようとする課題】
そこで、本発明は従来のキャスター旋回装置の上記不具合を解消するために提供されたもので、その目的とするところは、簡単な構成で防錆性と旋回性に優れるキャスター旋回装置を提供することにある。また、ボートキャスターのようなキャスター旋回装置自体を水中で作動させても防錆性を維持できる旋回性に優れるキャスター旋回装置を提供することにある。
【０００８】
【課題を解決するための手段】
以下、上記課題を解決するために、本発明が採った手段を説明する。
【０００９】
上記課題を解決するために、請求項１に記載のキャスター旋回装置が採った手段は、「柱状体でその上面は台車等の運搬体に固着され、その下面はベアリングボールを収納する円環状ボール溝が刻設される固定部と、
上部と下部とからなり、上部は柱状体でその上面は前記固定部に刻設される前記円環状ボール溝に相対向する円環状ボール溝が刻設され、下部は前記上部から垂設される車輪支持脚である、前記固定部と連通して形成される軸挿通孔に挿入される軸により支持され前記ベアリングボールを介して旋回自在な車輪支持部と、
からなるキャスター旋回装置において、
前記固定部と前記車輪支持部に刻設される前記円環状ボール溝を前記ベアリングボールの半径寸法より浅い溝深さに刻設することにより、前記固定部と前記車輪支持部を接触させることなく両者間に間隙を形成し、前記円環状ボール溝より外周方向にある前記間隙の一部に、円環状シールの断面形状が六角形に形成され、固定部における逆凹部の上面と車輪支持部の水平面とが線接触するように挟着されることを特徴とするキャスター旋回装置」を内容とする。
【００１０】
請求項１に記載のキャスター旋回装置は、固定部と車輪支持部と円環状シールとからなる簡単な構成を採り、固定部と車輪支持部の間には、間隙が形成される。そして、円環状ボール溝より外周方向にある間隙には、円環状シールが挟着されるので、間隙内は浸水しにくく、ベアリングボールや間隙内が錆びることを防ぐことができる。また、円環状シールは主に固定部と摺動するだけなので、円環状シールに対する摩擦抵抗が小さくなりキャスター旋回装置を円滑に旋回させることができる。
【００１１】
固定部と車輪支持部の上部は柱状体により形成され、この柱状体は通常円柱体で形成されるが、八角柱等の角柱体であってもよく、また通常前記柱状体は扁平に形成される。
【００１２】
円環状シールは、耐水性、耐摩耗性及び機械的強度のある材料から形成され、合成樹脂、合成ゴム等が好適に使用できる。また、挟着による密着性を高めるためには、弾性を備える材料が好ましい。さらに、摩擦抵抗を減じるために潤滑性をも備える材料、例えばウレタン、四フッ化エチレン、メラミン、ポリエチレン等を好適に使用できる。そして、このように形成される円環状シールは、間隙内に挟着される。
【００１３】
上記課題を解決するために請求項２に記載のキャスター旋回装置が採った手段は、「固定部は断面形状が逆凹字状の円柱体で、固定部下面には円環状ボール溝が刻設され、車輪支持部の上部は断面形状が凸字状の円柱体で、この円柱体の凸部の上面には円環状ボール溝が刻設され、前記固定部と前記車輪支持部間に形成される間隙に円環状シールが挟着されること」を内容とする。
【００１４】
請求項２に記載のキャスター旋回装置においては、固定部と車輪支持部間に円環状の間隙が形成されるので、この間隙内に挟着される円環状シールは主に固定部と摺動するだけなので摩擦抵抗が小さくなり摺動が滑らかで、キャスター旋回装置を円滑に旋回させることができると共に、上記間隙内は浸水しにくくなり、ベアリングボールや間隙内が錆びることを防ぐことができる。
【００１６】
上記課題を解決するために請求項３に記載のキャスター旋回装置が採った手段は、「円環状シールは、ウレタン樹脂により形成され、固定部と車輪支持部間に形成される間隙に挟着されること」を内容とする。
【００１７】
請求項３に記載のキャスター旋回装置は、固定部と車輪支持部間の間隙には耐水性、耐摩耗性、機械的強度及び潤滑性に優れるウレタン樹脂からなる円環状シールが挟着されるので、キャスター旋回装置を頻回に旋回させても摩耗しにくく、耐久性と旋回性に優れた防錆性のあるキャスター旋回装置を得ることができる。
【００１８】
さらに、キャスター旋回装置が採った手段は、「円環状シールは、ゴム部材を基材とし、このゴム部材の少なくとも固定部と車輪支持部の各接触面側に四フッ化エチレン樹脂層が接着されて形成され、固定部と車輪支持部間に形成される間隙に挟着されること」を内容とすることもできる。
【００１９】
さらに、係るキャスター旋回装置は、固定部と車輪支持部間にできる間隙に基材たるゴム部材を少なくとも固定部と車輪支持部の各接触面側に潤滑性の高い四フッ化エチレン樹脂層が接着される円環状シールが挟着されるので、摺動がより滑らかとなり、防錆性に優れるだけでなく、キャスター旋回装置の旋回がより円滑になる。
【００２０】
さらに、キャスター旋回装置は、「柱状体でその上面は台車等の運搬体に固着され、前記柱状体の下面はベアリングボールを収納する円環状ボール溝が刻設される固定部と、上部と下部とからなり、上部は柱状体でその上面は前記固定部に形成される前記円環状ボール溝に相対向する円環状ボール溝が刻設され、下部は前記上部から垂設される車輪支持脚である、前記固定部と前記車輪支持部に連通して形成される軸挿通孔に挿入される軸により支持され前記ベアリングボードを介して旋回自在な車輪支持部とからなるキャスター旋回装置において、前記固定部と前記車輪支持部に刻設される円環状ボール溝を前記ベアリングボールの半径寸法より浅い溝深さに刻設することにより、前記固定部と前記車輪支持部を接触させることなく両者間に間隙を形成し、この間隙内の壁面及び軸挿通孔の壁面を防錆性被膜でコーティングし、前記ベアリングボールを防錆性材料により形成したこと」を内容とすることもできる。
【００２１】
係るキャスター旋回装置は、上記構成により固定部及び車輪支持部内に水が浸入しても、これら固定部と車輪支持部間の間隙内の壁面や軸挿通孔の壁面は錆ることがない。防錆性被膜には、フッ素樹脂、ナイロン、ポリエチレン等のコーティングや溶融亜鉛メッキ、ユニクロームメッキ等の金属メッキが例示される。また、ベアリングボールは防錆性材料により形成されるので、上記と同様に水が浸入しても錆びることがない。防錆性材料からなるベアリングボールには、ステンレス、セラミックス等により形成されるものが例示される。このように、係るキャスター旋回装置は、固定部と車輪支持部間の間隙内に円環状シールを挟着しなくとも防錆が可能で、簡単な構成で円滑にキャスター旋回装置を旋回させることができる。
【００２２】
さらに、キャスター旋回装置は、「固定部は断面形状が逆凹字状の円柱体で、この固定部下面には円環状ボール溝が刻設され、車輪支持部の上部は断面形状が凸字状の円柱体で、この円柱体の凸部の上面には円環状ボール溝が刻設され、前記固定部と前記車輪支持部間の間隙内の壁面及び軸挿通孔の壁面を防錆性被膜でコーティングしたこと」を内容とすることもできる。
【００２３】
係るキャスター旋回装置は、円柱状の中空である逆凹部を備える固定部と円柱状の凸部を備える車輪支持部間に形成される間隙内のすべての壁面と軸挿通孔の壁面が防錆性被膜でコーティングされるので、キャスター旋回装置内が錆びることがない。また、間隙内に円環状シールが挟着されないので、円環状シールが固定部や車輪支持部と摺動することがなく、より滑らかにキャスターを旋回させることができる。
【００２４】
さらに、キャスター旋回装置が採った手段は、「固定部と車輪支持部間の間隙内の壁面及び軸挿通孔の壁面をコーティングする防錆性被膜が四フッ化エチレン樹脂であること」を内容とすることもできる。
【００２５】
係るキャスター旋回装置は、固定部と車輪支持部間の間隙内の壁面及び軸挿通孔の壁面が四フッ化エチレン樹脂でコーティングされるので、防錆はもちろんのこと、潤滑性のある四フッ化エチレン樹脂により旋回が滑らかとなり、キャスター旋回装置を円滑に旋回させることができる。
【００２６】
【発明の実施の形態】
以下、図面に基づいて本発明を詳細に説明する。
【００２７】
図１は固定部２１を断面形状が逆凹字状の扁平な円柱体に形成し、車輪支持部２２の上部を断面形状が凸字状の扁平な円柱体に形成し、間隙２６には円環状シール１０が挟着される第１の実施の形態に係るキャスター旋回装置５０を示す一部切欠き側面図である。図２は前記キャスター旋回装置５０を詳細に示す図１の部分拡大図である。
【００２８】
固定部２１及び車輪支持部２２は通常鋳物で形成されるが、剛性の高い材料であれば他の金属やプラスチック等からなる材料から形成してもよい。固定部２１には、台車等に固定部２１を固着させるためのフランジ３３が形成され、台車等に螺合される。図１及び図２に示すように固定部２１は、断面形状が逆凹字状の扁平な円柱体に形成されるので、その内側には扁平な円柱状中空である逆凹部２１ａが形成される。また、車輪支持部２２の上部は断面形状が凸字状の扁平な円柱体に形成されるので、扁平な円柱状の凸部２２ａが形成される。前記逆凹部２１ａの上面にはベアリングボール２４の円環状ボール溝２３ａが刻設され、該円環状ボール溝２３ａに相対向して前記凸部２２ａの上面に刻設されるベアリングボール２４の円環状ボール溝２３ｂとの間に多数のベアリングボール２４が収納されるので、車輪支持部２２は固定部２１に沿って旋回自在となる。そして、凸部２２ａの直径は凹部２１ａの直径より僅かに縮形して形成されているため、固定部２１と車輪支持部２２間には間隙２６が形成されることとなる。そして、車輪支持部２２の下部は上部から垂設される車輪支持脚３０からなり車輪３４を支持する。
【００２９】
固定部２１と車輪支持部２２の各々の中心部には、軸２５を挿入するための軸挿通孔３２が連通して形成されており、この軸挿通孔３２に挿入される軸２５で車輪支持部２２は支持される。この軸２５はボルトからなり、該ボルトは固定部２１の軸挿通孔３２に挿入され、車輪支持部２２の上部の下端部中央にパッキン２７を介装させてナット３１により旋回可能に螺合されるので、軸挿通孔３２の内部を浸水しにくくすることができる。
【００３０】
また、固定部２１と車輪支持部２２に各々刻設されるベアリングボール２４の円環状ボール溝２３ａ、２３ｂは、ベリングボール２４の半径寸法より浅い溝深さに刻設されているので、ベアリングボール２４は上下に相対向して刻設される円環状ボール溝２３ａ、２３ｂ内に収まりきらず、固定部２１の下面と車輪支持部２２の上面は接触することなく、固定部２１と車輪支持部２２間には間隙２６ができることとなり、キャスター旋回装置５０は旋回可能となる。また、ベアリングボール２４を安定して収納するためには、円環状ボール溝２３ａ、２３ｂの溝周り長を前記ベアリングボール２４の半径より長く形成することが好ましい。
【００３１】
なお、ベアリングボール２４は、剛性のある材料で形成され、ステンレス等の合金やセラミックス等が例示される。
【００３２】
上記間隙２６内には、図１及び図２に示すようにウレタン樹脂からなる円環状シール１０が挟着されるので、キャスター旋回装置５０内を浸水しにくくすることができる。ウレタン樹脂はエーテル系、エステル系のいずれでもよい。また、ウレタン樹脂には、ステアリン酸亜鉛等の滑剤やガラス繊維、セラミック繊維、カーボン繊維、タルク等の充填剤を加えてもよい。また、図２に詳細に示すように円環状シール１０は、断面形状が六角形状に形成され、固定部２１下面と車輪支持部２２の水平面２２ｃとは、線接触するように挟着されるので摩擦抵抗が小さくなり、キャスター旋回装置５０は防錆性と共に旋回性に優れる。また、円環状シール１０は耐摩耗性に優れるウレタン樹脂により形成されるので、キャスター旋回装置５０は耐久性に優れる。なお、円環状シール１０により閉状態になる間隙２６内にはグリスが充填される。
【００３３】
図３は、固定部２１と車輪支持部２２が第１の実施の形態に係るキャスター旋回装置５０と同様の構造に形成されたキャスター旋回装置５０であって、固定部２１と車輪支持部２２間にできる間隙２６ｂにゴム部材１１ａを基材とし、ゴム部材１１ａの固定部２１と車輪支持部２２の接触面に四フッ化エチレン樹脂層を接着した円環状シール１１（１１ａ、１１ｂ）を挟着した第２の参考形態に係るキャスター旋回装置５０を示す。なお、四フッ化エチレン樹脂の接着層１１ｂは、接着剤によりゴム部材１１ａに接着されている。
【００３４】
この円環状シール１１（１１ａ、１１ｂ）は、図４に詳細に示すように、このゴム部材１１ａの四フッ化エチレン樹脂の接着層１１ｂは、主として間隙２６内における固定部２１の水平面２１ｃと摺動し、また四フッ化エチレン樹脂は極めて潤滑性が高いので、摩擦抵抗が小さくキャスター旋回装置５０を円滑に旋回させることができる。
【００３５】
図５及び図６は、固定部２１と車輪支持部２２が図１及び図２に示す第１の実施の形態に係るキャスター旋回装置５０と同様の構造に形成されたキャスター旋回装置５０であって、固定部２１と車輪支持部２２間に形成される間隙２６内の壁面２８及び軸挿通孔３２の壁面２９を四フッ化エチレン樹脂の防錆性被膜１２を粉末溶射法によりコーティングし、ステンレスで形成されたベアリングボール２４を使用する第３の実施の形態に係るキャスター旋回装置５０を示す。四フッ化エチレン樹脂は、水に濡れにくいという特性を備えるので、固定部２１内や車輪支持部２２内が浸水しても、間隙２６内の壁面２８及び軸挿通孔３２の壁面２９は錆びることがない。また、四フッ化エチレン樹脂は潤滑性が高いので、円環状ボール溝をもコーティングすることによりベアリングボール２４の回転が滑らかになり、キャスター旋回装置５０をより円滑に旋回させることができる。さらに、ベアリングボール２４はステンレスにより形成されているので、錆びることがない。また、本発明に係るキャスター旋回装置５０は円環状シール１０、１１を形成する必要がなく、また車輪支持部２２の下端部中央にパッキン２７を介装する必要もないので、キャスター旋回装置５０は簡単な構成でより円滑に旋回させることができる。
【００３６】
【発明の効果】
本発明は、以上説明したように構成されているので、以下に記載されるような効果を奏する。
【００３７】
請求項１に記載のキャスター旋回装置５０は、固定部２１と車輪支持部２２間に形成される間隙２６内に円環状シール１０、１１が挟着されるので、キャスター旋回装置５０は防錆性に優れ、ベアリングボール２４や間隙２６内が錆びることを防ぐことができ、耐久性に優れたキャスター旋回装置５０が得られる。また、円環状シール１０、１１は主に間隙２６内の固定部２１と摺動するだけなので、円環状シール１０、１１に対する摩擦抵抗は小さく、旋回性に優れたキャスター旋回装置５０内を簡単な構成で安価に製造できる。
【００３８】
請求項２に記載のキャスター旋回装置５０において、車輪支持部２２における円柱状の凸部２２ａの直径は、固定部２１に形成される中空状で円柱状の逆凹部２１ａの直径より縮径して形成されるので、間隙２６が形成され、円環状シール１０、１１を間隙２６に挟着でき、上記効果に加え、種々の防錆性に優れるキャスター旋回装置を提供することができる。
【００３９】
請求項３に記載のキャスター旋回装置５０は、円環状シール１０が耐水性、耐摩耗性、機械的強度及び潤滑性に優れるウレタン樹脂で形成されるので、上記請求項１の効果に加え、より耐久性と摺動性に優れるキャスター旋回装置５０を得ることができる。
【００４０】
また、円環状シール１１（１１ａ、１１ｂ）の少なくとも固定部２１と車輪支持部２２の各接触面側に潤滑性に優れる四フッ化エチレン樹脂層が接着されるので、上記請求項１の効果に加え、より摺動が滑らかとなり、より旋回性に優れたキャスター旋回装置５０を得ることができる。
【図面の簡単な説明】
【図１】第１の実施の形態に係るキャスター旋回装置を示す一部切欠き側面図である。
【図２】図１の部分拡大図である。
【図３】第２の実施の形態に係るキャスター旋回装置を示す一部切欠き側面図である。
【図４】図３の部分拡大図である。
【図５】第３の実施の形態に係るキャスター旋回装置を示す一部切欠き側面図である。
【図６】図５の部分拡大図である。
【符号の説明】
１０．１１．円環状シール
１１ａ．ゴム部材
１１ｂ．四フッ化エチレン樹脂の接着層
１２．防錆性被膜
２１．固定部
２２．車輪支持部
２３ａ．２３ｂ．円環状ボール溝
２４．ベアリングボール
２５．軸
２６．間隙
２８．固定部と車輪支持部間にできる間隙の壁面
２９．軸挿通孔の壁面
３０．車輪支持脚
３２．軸挿通孔
５０．キャスター旋回装置[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a caster swivel device, and more particularly to a caster swivel device that has a simple structure that can be used even in an environment that is easily exposed to water, and that is excellent in rust prevention and swivel properties. The present invention relates to a caster turning device that can maintain rust prevention even when operated in water.
[0002]
[Prior art]
Casters are widely used for carts, wagons, furniture, and so on. By the way, some of the casters are used in an environment that is easily exposed to water, and examples include boat casters and carts that enter and exit the freezer compartment. And if you continue to use under such circumstances, water will enter the caster swivel device and rust will be generated, causing trouble in turning performance, and finally when rust rises, It was impossible to turn, and durability could be significantly reduced.
[0003]
Therefore, a caster turning device with a waterproof measure has been provided conventionally.
[0004]
For example, the fixed plate and the bearing plate are brought close to each other, the outer peripheral edge of the lower circular portion of the fixed plate and the outer peripheral edge of the upper circular portion of the bearing plate are formed in an arc shape, and the space portion generated between the outer peripheral edges is formed. A caster wheel is provided in which a rubber O-ring having a circular cross section is press-contacted (see JP-A-6-143907). However, in this caster wheel, since the rubber O-ring is pressed against both the fixed plate and the bearing plate, there is a possibility that the frictional resistance is increased and the smooth rotation of the caster is hindered.
[0005]
Further, a caster is provided in which a sealing material is liquid-tightly interposed between the outer peripheral edge of the horizontal engagement plate of the crotch bracket that pivots the wheel and the protruding edge of the base plate (see Japanese Utility Model Publication No. 56-20242). However, since this caster also has both the crotch metal fitting and the base plate interposed in a liquid-tight manner by a sealing material, there is a possibility that the frictional resistance increases as described above and the smooth rotation of the caster is hindered.
[0006]
Further, the conventional waterproof caster swivel device is used in a place where there is a lot of moisture, such as a cart entering and exiting a freezer compartment, and is severe such as operating the caster swivel device underwater like a boat caster. Not suitable for use under conditions.
[0007]
[Problems to be solved by the invention]
Accordingly, the present invention is provided to solve the above-described problems of the conventional caster swiveling device, and its object is to provide a caster swiveling device that has a simple structure and is excellent in rust prevention and swiveling properties. It is in. It is another object of the present invention to provide a caster swivel device that is excellent in swivelability that can maintain rust prevention even when a caster swivel device such as a boat caster is operated in water.
[0008]
[Means for Solving the Problems]
Hereinafter, the means taken by the present invention to solve the above problems will be described.
[0009]
In order to solve the above-mentioned problem, the means adopted by the caster turning device according to claim 1 is as follows: "A columnar body whose upper surface is fixed to a carrier such as a carriage, and whose lower surface is an annular ball for housing a bearing ball. A fixing part in which a groove is engraved,
It consists of an upper part and a lower part, the upper part is a columnar body, the upper surface is engraved with an annular ball groove opposite to the annular ball groove engraved in the fixed part, and the lower part is suspended from the upper part A wheel support leg, a wheel support part supported by a shaft inserted into a shaft insertion hole formed in communication with the fixed part and pivotable via the bearing ball;
In the caster turning device consisting of
By engraving the annular ball groove carved in the fixed part and the wheel support part to a groove depth shallower than the radial dimension of the bearing ball, the fixed part and the wheel support part are not brought into contact with each other. A gap is formed between the two and the cross-sectional shape of the annular seal is formed in a hexagonal shape in a part of the gap in the outer circumferential direction from the annular ball groove . The contents of the caster swivel device are characterized by being sandwiched so as to be in line contact with the horizontal plane .
[0010]
The caster turning device according to the first aspect adopts a simple configuration including a fixing portion, a wheel support portion, and an annular seal, and a gap is formed between the fixing portion and the wheel support portion. Since the annular seal is sandwiched in the gap in the outer peripheral direction from the annular ball groove, it is difficult for the inside of the gap to be submerged and the bearing ball and the gap can be prevented from being rusted. Further, since the annular seal mainly slides with the fixed portion, the frictional resistance against the annular seal is reduced, and the caster turning device can be smoothly turned.
[0011]
The upper part of the fixed part and the wheel support part is formed by a columnar body, and this columnar body is usually formed by a cylindrical body, but may be a prismatic body such as an octagonal column, and the columnar body is usually formed flat. The
[0012]
The annular seal is formed of a material having water resistance, wear resistance and mechanical strength, and a synthetic resin, a synthetic rubber or the like can be suitably used. Moreover, in order to improve the adhesiveness by pinching, the material provided with elasticity is preferable. Furthermore, a material having lubricity in order to reduce the frictional resistance, such as urethane, tetrafluoroethylene, melamine, polyethylene, etc. can be suitably used. The annular seal formed in this way is sandwiched in the gap.
[0013]
In order to solve the above-mentioned problem, the means adopted by the caster turning device according to claim 2 is as follows: “The fixing portion is a cylindrical body having a reverse concave shape in cross section, and an annular ball groove is formed on the lower surface of the fixing portion. The upper part of the wheel support part is a cylindrical body having a convex cross section, and an annular ball groove is formed on the upper surface of the convex part of the cylindrical body, and is formed between the fixed part and the wheel support part. The annular seal is sandwiched between the gaps ”.
[0014]
In the caster turning device according to claim 2 , since an annular gap is formed between the fixed portion and the wheel support portion, the annular seal sandwiched in the gap mainly slides on the fixed portion. Therefore, the frictional resistance is reduced, the sliding is smooth, the caster turning device can be smoothly turned, the inside of the gap is difficult to be submerged, and the bearing ball and the inside of the gap can be prevented from being rusted.
[0016]
In order to solve the above-mentioned problem, the means adopted by the caster turning device according to claim 3 is as follows: “The annular seal is formed of urethane resin and is sandwiched between gaps formed between the fixed portion and the wheel support portion. "".
[0017]
In the caster turning device according to claim 3, an annular seal made of urethane resin having excellent water resistance, wear resistance, mechanical strength and lubricity is sandwiched between the fixed portion and the wheel support portion. Even if the caster swiveling device is swung frequently, it is hard to be worn, and a caster swiveling device having rust resistance and excellent durability and swiveling property can be obtained.
[0018]
Further, the means adopted by the caster turning device is: “The annular seal is made of a rubber member as a base material, and a tetrafluoroethylene resin layer is adhered to at least the contact surface side of the fixed portion and the wheel support portion of the rubber member. It is also possible for the content to be “to be formed and sandwiched in a gap formed between the fixed portion and the wheel support portion”.
[0019]
Further, the caster turning device has a rubber member as a base material in a gap formed between the fixed part and the wheel support part, and a highly lubricated tetrafluoroethylene resin layer is bonded to at least each contact surface side of the fixed part and the wheel support part. Since the annular seal is sandwiched, the sliding becomes smoother and the rust prevention is not only excellent, but also the turning of the caster turning device becomes smoother.
[0020]
Furthermore, the caster swivel device has a "columnar body, the upper surface of which is fixed to a carrier such as a carriage, and the lower surface of the columnar body is provided with a fixed portion in which an annular ball groove for housing a bearing ball is engraved, and an upper portion and a lower portion. The upper part is a columnar body, the upper surface is engraved with an annular ball groove opposed to the annular ball groove formed in the fixed part, and the lower part is a wheel support leg suspended from the upper part. The caster swivel device comprising a wheel support portion supported by a shaft inserted into a shaft insertion hole formed in communication with the fixed portion and the wheel support portion, the wheel support portion being turnable via the bearing board. An annular ball groove formed on the wheel support portion and the wheel support portion is formed at a groove depth shallower than the radial dimension of the bearing ball, so that the fixed portion and the wheel support portion are not in contact with each other. To form a gap, the wall surfaces of the wall and the shaft insertion hole in the gap coated with rust-preventive coating, wherein the bearing balls formed by rust material "a may also be a content.
[0021]
Even if water permeates into the fixed part and the wheel support part with the above-described configuration, the caster turning device does not rust on the wall surface in the gap between the fixed part and the wheel support part or the wall surface of the shaft insertion hole. Examples of the anticorrosive film include coatings such as fluororesin, nylon and polyethylene, and metal plating such as hot dip galvanization and unichrome plating. Further, since the bearing ball is formed of a rust-proof material, it does not rust even when water enters as described above. Examples of bearing balls made of a rust-proof material include those formed of stainless steel, ceramics, and the like. Thus, the caster swiveling device can prevent rust without sandwiching an annular seal in the gap between the fixed portion and the wheel support portion, and can smoothly swivel the caster swiveling device with a simple configuration. it can.
[0022]
Furthermore, the caster swivel device says, "The fixed part is a cylindrical body with a cross-sectionally inverted concave shape, and an annular ball groove is engraved on the lower surface of this fixed part, and the upper part of the wheel support part is convex in cross-sectional shape. An annular ball groove is formed on the upper surface of the convex portion of the cylindrical body, and the wall surface in the gap between the fixed portion and the wheel support portion and the wall surface of the shaft insertion hole are covered with a rust-proof coating. "Coating" can also be included.
[0023]
The caster swivel device is rustproof on all wall surfaces in the gap formed between the fixed portion having the reverse hollow concave portion and the wheel support portion having the cylindrical convex portion and the wall surface of the shaft insertion hole. Since it is coated with a film, the inside of the caster turning device will not rust. Further, since the annular seal is not sandwiched in the gap, the annular seal does not slide with the fixed portion or the wheel support portion, and the caster can be rotated more smoothly.
[0024]
Furthermore, the means adopted by the caster turning device is that the rust preventive coating that coats the wall surface in the gap between the fixed part and the wheel support part and the wall surface of the shaft insertion hole is tetrafluoroethylene resin. You can also
[0025]
Since the caster turning device is coated with tetrafluoroethylene resin on the wall surface in the gap between the fixed part and the wheel support part and the wall surface of the shaft insertion hole, not only rust prevention but also lubricated tetrafluoride is provided. The turning is smooth by the ethylene resin, and the caster turning device can be turned smoothly.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings.
[0027]
Figure 1 is formed in a flat cylindrical body of the fixing part 21 is cross-sectional shape inverted concave shape, the upper portion of the wheel support portion 22 is the cross-sectional shape formed in a convex-shaped flat cylinder, while gap 26 is It is a partially notched side view which shows the caster turning apparatus 50 which concerns on 1st Embodiment by which the annular seal 10 is clamped. FIG. 2 is a partially enlarged view of FIG. 1 showing the caster turning device 50 in detail.
[0028]
The fixed portion 21 and the wheel support portion 22 are usually formed of a casting, but may be formed of a material made of other metals, plastics, or the like as long as the material is highly rigid. The fixing portion 21 is formed with a flange 33 for fixing the fixing portion 21 to a cart or the like and is screwed to the cart or the like. As shown in FIGS. 1 and 2, the fixing portion 21 is formed in a flat cylindrical body having a reverse concave shape in cross section, and therefore, a reverse concave portion 21 a that is a flat cylindrical hollow is formed inside thereof. . Moreover, since the upper part of the wheel support part 22 is formed in a flat cylindrical body having a convex cross-sectional shape, a flat cylindrical convex part 22a is formed. An annular ball groove 23a of a bearing ball 24 is formed on the upper surface of the reverse concave portion 21a, and an annular shape of the bearing ball 24 is formed on the upper surface of the convex portion 22a so as to face the annular ball groove 23a. Since a large number of bearing balls 24 are accommodated between the ball grooves 23 b, the wheel support portion 22 can turn along the fixed portion 21. Since the diameter of the convex portion 22a is slightly smaller than the diameter of the concave portion 21a, a gap 26 is formed between the fixed portion 21 and the wheel support portion 22. And the lower part of the wheel support part 22 consists of the wheel support leg 30 suspended from the upper part, and supports the wheel 34. As shown in FIG.
[0029]
A shaft insertion hole 32 for inserting the shaft 25 is formed in the center of each of the fixed portion 21 and the wheel support portion 22, and the wheel 25 is supported by the shaft 25 inserted into the shaft insertion hole 32. Part 22 is supported. The shaft 25 is composed of a bolt, and the bolt is inserted into the shaft insertion hole 32 of the fixed portion 21 and is screwed so as to be pivotable by a nut 31 with a packing 27 interposed in the center of the lower end portion of the upper portion of the wheel support portion 22. Therefore, the inside of the shaft insertion hole 32 can be made difficult to be submerged.
[0030]
Further, the annular ball grooves 23a and 23b of the bearing ball 24 respectively carved in the fixed portion 21 and the wheel support portion 22 are carved into a groove depth shallower than the radial dimension of the belling ball 24. 24 does not fit in the annular ball grooves 23a and 23b engraved opposite to each other in the vertical direction, and the lower surface of the fixed portion 21 and the upper surface of the wheel support portion 22 do not contact each other, and the fixed portion 21 and the wheel support portion 22 A gap 26 is formed between them, and the caster turning device 50 can turn. Further, in order to stably store the bearing ball 24, it is preferable that the circumferential length of the annular ball grooves 23a and 23b is longer than the radius of the bearing ball 24.
[0031]
The bearing ball 24 is formed of a rigid material, and examples thereof include alloys such as stainless steel and ceramics.
[0032]
Since the annular seal 10 made of urethane resin is sandwiched in the gap 26 as shown in FIGS. 1 and 2, it is possible to make it difficult for the caster turning device 50 to be submerged. The urethane resin may be either ether type or ester type. In addition, a lubricant such as zinc stearate and a filler such as glass fiber, ceramic fiber, carbon fiber, and talc may be added to the urethane resin. Further, as shown in detail in FIG. 2, the annular seal 10 has a hexagonal cross section, and the lower surface of the fixed portion 21 and the horizontal surface 22 c of the wheel support portion 22 are sandwiched so as to be in line contact with each other. The frictional resistance is reduced, and the caster turning device 50 is excellent in turning performance as well as rust prevention. Further, since the annular seal 10 is formed of a urethane resin having excellent wear resistance, the caster turning device 50 is excellent in durability. The gap 26 that is closed by the annular seal 10 is filled with grease.
[0033]
FIG. 3 shows a caster turning device 50 in which the fixed portion 21 and the wheel support portion 22 are formed in the same structure as the caster turning device 50 according to the first embodiment, and between the fixed portion 21 and the wheel support portion 22. An annular seal 11 (11a, 11b) in which a rubber member 11a is used as a base material and a tetrafluoroethylene resin layer is bonded to the contact surface of the fixing portion 21 and the wheel support portion 22 of the rubber member 11a is sandwiched in the gap 26b. The caster turning apparatus 50 according to the second reference embodiment is shown. The adhesive layer 11b of tetrafluoroethylene resin is bonded to the rubber member 11a with an adhesive.
[0034]
As shown in detail in FIG. 4, the annular seal 11 (11 a, 11 b) is formed by sliding the tetrafluoroethylene resin adhesive layer 11 b of the rubber member 11 a mainly on the horizontal surface 21 c of the fixed portion 21 in the gap 26. Further, since the tetrafluoroethylene resin has extremely high lubricity, the frictional resistance is small and the caster turning device 50 can be smoothly turned.
[0035]
5 and 6 show a caster turning device 50 in which the fixing portion 21 and the wheel support portion 22 are formed in the same structure as the caster turning device 50 according to the first embodiment shown in FIGS. 1 and 2. The wall surface 28 in the gap 26 formed between the fixed portion 21 and the wheel support portion 22 and the wall surface 29 of the shaft insertion hole 32 are coated with a rustproof coating 12 of tetrafluoroethylene resin by a powder spraying method, and made of stainless steel. A caster turning device 50 according to a third embodiment using a formed bearing ball 24 is shown. Since the tetrafluoroethylene resin has a characteristic that it is difficult to get wet with water, the wall surface 28 in the gap 26 and the wall surface 29 of the shaft insertion hole 32 are rusted even if the inside of the fixed portion 21 or the wheel support portion 22 is submerged. There is no. Further, since the tetrafluoroethylene resin has high lubricity, the bearing ball 24 can be smoothly rotated by coating the annular ball groove, and the caster turning device 50 can be turned more smoothly. Furthermore, since the bearing ball 24 is made of stainless steel, it does not rust. Further, the caster turning device 50 according to the present invention does not need to form the annular seals 10 and 11, and it is not necessary to interpose the packing 27 at the center of the lower end portion of the wheel support portion 22. It can be turned more smoothly with a simple configuration.
[0036]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
[0037]
In the caster turning device 50 according to the first aspect, since the annular seals 10 and 11 are sandwiched in a gap 26 formed between the fixed portion 21 and the wheel support portion 22, the caster turning device 50 has an antirust property. Thus, it is possible to prevent the bearing ball 24 and the gap 26 from being rusted, and the caster turning device 50 having excellent durability can be obtained. Further, since the annular seals 10 and 11 mainly slide only with the fixed portion 21 in the gap 26, the frictional resistance against the annular seals 10 and 11 is small, and the inside of the caster turning device 50 excellent in turning performance can be easily obtained. The structure can be manufactured at low cost.
[0038]
In the caster turning device 50 according to claim 2 , the diameter of the columnar convex portion 22a in the wheel support portion 22 is smaller than the diameter of the hollow and cylindrical reverse concave portion 21a formed in the fixed portion 21. Since it is formed, a gap 26 is formed, and the annular seals 10 and 11 can be sandwiched between the gaps 26. In addition to the above effects, a caster swivel device having various rust prevention properties can be provided.
[0039]
In the caster turning device 50 according to claim 3, since the annular seal 10 is formed of urethane resin having excellent water resistance, wear resistance, mechanical strength and lubricity, in addition to the effect of the above-mentioned claim 1, The caster turning device 50 having excellent durability and slidability can be obtained.
[0040]
Further , since the tetrafluoroethylene resin layer having excellent lubricity is adhered to at least the contact surface side of the fixed portion 21 and the wheel support portion 22 of the annular seal 11 (11a, 11b), the effect of the above-mentioned claim 1 is achieved. in addition, more sliding is smooth, it is possible to obtain a caster swivel 50 having more excellent turning performance.
[Brief description of the drawings]
FIG. 1 is a partially cutaway side view showing a caster turning device according to a first embodiment.
FIG. 2 is a partially enlarged view of FIG.
FIG. 3 is a partially cutaway side view showing a caster turning device according to a second embodiment.
4 is a partially enlarged view of FIG. 3;
FIG. 5 is a partially cutaway side view showing a caster turning device according to a third embodiment.
6 is a partially enlarged view of FIG. 5;
[Explanation of symbols]
10.11. Annular seal 11a. Rubber member 11b. 11. Adhesive layer of tetrafluoroethylene resin Antirust coating 21. Fixing part 22. Wheel support 23a. 23b. Annular ball groove 24. Bearing ball 25. Shaft 26. Gap 28. Wall surface of gap formed between fixed part and wheel support part 29. Wall surface of shaft insertion hole 30. Wheel support leg 32. Shaft insertion hole 50. Caster swivel

Claims

A columnar body whose upper surface is fixed to a carrier such as a carriage, and whose lower surface is a fixed portion in which an annular ball groove for housing a bearing ball is engraved,
It consists of an upper part and a lower part, the upper part is a columnar body, the upper surface is engraved with an annular ball groove opposite to the annular ball groove engraved in the fixed part, and the lower part is suspended from the upper part A wheel support leg, a wheel support part supported by a shaft inserted into a shaft insertion hole formed in communication with the fixed part and pivotable via the bearing ball;
In the caster turning device consisting of
By engraving the annular ball groove carved in the fixed part and the wheel support part to a groove depth shallower than the radial dimension of the bearing ball, the fixed part and the wheel support part are not brought into contact with each other. A gap is formed between the two, and an annular seal having a hexagonal cross-sectional shape is formed in a part of the gap in the outer circumferential direction from the annular ball groove . A caster swivel device characterized by being sandwiched so as to be in line contact with a horizontal plane .

The fixed part is a cylindrical body having an inverted concave cross section, and an annular ball groove is engraved on the lower surface of the fixed part, and the upper part of the wheel support part is a cylindrical body having a convex cross section. annular ball groove on the upper surface of the convex portion are engraved, according to claim 1, gap annularly seal formed between the said fixed part wheel support portion, characterized in that it is clamped Caster turning device.

The caster turning device according to claim 1 or 2, wherein the annular seal is formed of urethane resin and is sandwiched in a gap formed between the fixed portion and the wheel support portion.