JP4380169B2

JP4380169B2 - Thrust sliding bearing

Info

Publication number: JP4380169B2
Application number: JP2003030419A
Authority: JP
Inventors: 和幸宮田; 亮平金子
Original assignee: Oiles Corp
Current assignee: Oiles Corp
Priority date: 2003-02-07
Filing date: 2003-02-07
Publication date: 2009-12-09
Anticipated expiration: 2023-02-07
Also published as: JP2004239379A

Description

【０００１】
【発明の属する技術分野】
本発明は、スラスト滑り軸受、特に四輪自動車におけるストラット型サスペンション（マクファーソン式）の滑り軸受として組込まれて好適なスラスト滑り軸受、特に合成樹脂製のスラスト滑り軸受に関する。
【０００２】
【従来の技術】
一般に、ストラット型サスペンションは、主として四輪自動車の前輪に用いられ、主軸と一体となった外筒の中に油圧式ショックアブソーバを内蔵したストラットアッセンブリにコイルばねを組合せたものである。斯かるサスペンションは、ストラットの軸線に対してコイルばねの軸線を積極的にオフセットさせ、該ストラットに内蔵されたショックアブソーバのピストンロッドの摺動を円滑に行わせる構造のものと、ストラットの軸線に対してコイルばねの軸線を一致させて配置させる構造のものとがある。いずれの構造においても、ステアリング操作によりストラットアッセンブリがコイルばねと共に回転する際、当該回転を円滑に行わせるべく車体の取付部材とコイルばねの上部ばね座との間にスラスト軸受が配されている。
【０００３】
【特許文献１】
特開平１１−３０３８７３号公報
【特許文献２】
特開２００２−２５７１４６号公報
【０００４】
【発明が解決しようとする課題】
このスラスト軸受には、ボール若しくはニードルを使用したころがり軸受又は合成樹脂製の滑り軸受が使用されている。しかしながら、ころがり軸受は、微少揺動及び振動荷重等によりボール若しくはニードルに疲労破壊を生ずる虞があり、円滑なステアリング操作を維持し難いという問題がある。滑り軸受は、ころがり軸受に比べて摩擦トルクが高いので、スラスト荷重が大きくなると摩擦トルクが大きくなり、ステアリング操作を重くする上に、合成樹脂の組合せによっては、スティックスリップ現象を生じ、往々にして当該スティックスリップ現象に起因する摩擦音を発生するという問題がある。
【０００５】
また滑り軸受には、グリース等の潤滑剤が適用されるのであるが、斯かる潤滑剤が摺動面に所望に介在する限りにおいては、上記のような摩擦音は殆ど生じないのであるが、長期の使用による潤滑剤の消失等で摩擦音が生じ始める場合もあり得る。
【０００６】
なお、上記の問題は、ストラット型サスペンションに組込まれるスラスト滑り軸受に限って生じるものではなく、一般のスラスト滑り軸受においても同様に生じ得るのである。
【０００７】
本発明は前記諸点に鑑みてなされたものであって、その目的とするところは、グリース等の潤滑剤を長期に亘って摺動面に介在させることができる上に、斯かる潤滑剤をスラスト荷重受けにも利用でき、而して、スラスト荷重が大きくなっても摩擦トルクはほとんど変わらず、低い摩擦トルクをもって摺動面を構成できて、長期の使用でも斯かる低い摩擦係数を維持できる上に、摺動面での摩擦音の発生がなく、しかも、ストラット型サスペンションにスラスト滑り軸受として組込んでもころがり軸受と同等の滑らかなステアリング操作を確保し得るスラスト滑り軸受を提供することにある。
【０００８】
【課題を解決するための手段】
本発明の第一の態様のスラスト滑り軸受は、環状面を有した第一の軸受体と、この第一の軸受体に当該第一の軸受体の軸心の回りで回転自在となるように重ね合わされると共に第一の軸受体の環状面に対面した環状面を有する第二の軸受体と、両環状面に摺動自在に接触して両環状面間に介在されている小径の弾性リングと、小径の弾性リングと協働して環状の密閉空間を形成するように、両環状面に摺動自在に接触して両環状面間に介在されていると共に小径の弾性リングよりも大径であって小径の弾性リングの径方向の外側に配された大径の弾性リングと、密閉空間に充填された潤滑剤とを具備している。
【０００９】
第一の態様のスラスト滑り軸受によれば、小径及び大径の弾性リングにより形成された密閉空間に潤滑剤を充填しているために、密閉空間に配された潤滑剤を長期に亘って維持できる上に、密閉空間に維持された潤滑剤を小径及び大径の弾性リングと両環状面との間の摺動面に弾性リングの弾性変形により徐々に供給できて潤滑剤を長期に亘って摺動面に介在させることができる上に、密閉空間に充填された潤滑剤をスラスト荷重受けにも利用でき、而して、スラスト荷重が大きくなっても摩擦トルクはほとんど変わらず、低い摩擦トルクをもって摺動面を構成できて、長期の使用でも斯かる低い摩擦係数を維持できる上に、摺動面での摩擦音の発生がなく、しかも、ストラット型サスペンションにスラスト滑り軸受として組込んでもころがり軸受と同等の滑らかなステアリング操作を確保し得る。
【００１０】
斯かるスラスト滑り軸受では、好ましくは本発明の第二の態様のスラスト滑り軸受のように、小径及び大径の弾性リングは、スラスト荷重下で、密閉空間の容積を小さくするように撓み変形するようになっている。
【００１１】
本発明では、その第三の態様のスラスト滑り軸受のように、少なくとも、スラスト荷重下での小径及び大径の弾性リングの弾性変形により容積が減少された密閉空間を隙間なしに満たす量の潤滑剤を具備していればよいのであるが、その第四の態様のスラスト滑り軸受のように、スラスト無荷重下で密閉空間を隙間なしに満たす量の潤滑剤を具備していてもよい。
【００１２】
小径及び大径の弾性リングは、好ましくは本発明の第五の態様のスラスト滑り軸受のように、天然ゴム、合成ゴム又は熱可塑性エラストマーからなっており、小径及び大径の弾性リングの少なくとも一方の断面形状は、本発明の第六の態様のスラスト滑り軸受のように、略円形であっても、本発明の第七の態様のスラスト滑り軸受のように、各環状面に対面する側に環状の凹みを有した略矩形状であってもよい。
【００１３】
小径及び大径の弾性リングの夫々は、本発明の第八の態様のスラスト滑り軸受のように、各環状面に対面する面に環状の凹みを有していてもよく、この場合には、環状の各凹みは、小径及び大径の弾性リングの夫々の各環状面への接触で密閉されており、しかも、本発明の第九の態様のスラスト滑り軸受のように、斯かる密閉された環状の各凹みに更に潤滑剤が充填されているとよい。
【００１４】
潤滑剤は、本発明の第十の態様のスラスト滑り軸受のように、グリース及び潤滑油のうちの少なくとも一つを含んでおり、好ましくは本発明の第十一の態様のスラスト滑り軸受のように、シリコーン系グリースからなる。
【００１５】
本発明のスラスト滑り軸受では、両軸受体は、合成樹脂製であることが好ましく、具体的には、その第十二の態様の滑り軸受のように、ポリアセタール樹脂、ポリアミド樹脂、ポリエステル樹脂、ポリオレフィン樹脂、ポリカーボネート樹脂及びフッ素樹脂のうちの少なくとも一つを含む合成樹脂からなっているとよく、より好ましくは、その第十三の態様の滑り軸受のように、第一の軸受体は、ポリアセタール樹脂からなっており、第二の軸受体は、ポリアセタール樹脂、ポリアミド樹脂、ポリエステル樹脂、ポリオレフィン樹脂、ポリカーボネート樹脂及びフッ素樹脂のうちの少なくとも一つを含む合成樹脂からなっている。ポリエステル樹脂の場合は、熱可塑性ポリエステル樹脂が好ましい。
【００１６】
本発明のスラスト滑り軸受では、好ましくはその第十四の態様の滑り軸受のように、第一の軸受体は、その径方向の外周縁部で第二の軸受体に当該第二の軸受体の径方向の外周縁部において弾性嵌着されるようになっており、また、本発明の第十五の態様の滑り軸受のように、両軸受体のその径方向の外周縁部及び内周縁部のうちの少なくとも一方において両軸受体間には、ラビリンスが形成されるようになっており、斯かるラビリンスにより第一の軸受体と第二の軸受体との間の摺動面への塵埃、泥水等の侵入を好ましく阻止できるようになる。
【００１７】
本発明の第十六の態様の滑り軸受では、第二の軸受体は、その環状面に一体的に形成された大径及び小径の一対の環状突起を有しており、小径及び大径の弾性リングは、一対の環状突起のうちの大径の環状突起よりも径方向の内側に配されていると共に一対の環状突起のうちの小径の環状突起よりも径方向の外側に配されており、斯かる一対の環状突起により両弾性リングを径方向に関して位置決めできる上に、スラスト荷重下での両弾性リングの撓み方向を規制できて効果的に密閉空間の容積を減少できる。
【００１８】
次に本発明及びその実施の形態を、図に示す好ましい例を参照して説明する。なお、本発明はこれら例に何等限定されないのである。
【００１９】
【発明の実施の形態】
図１及び図２において、本例の四輪自動車におけるストラット型サスペンションに用いるためのスラスト滑り軸受１は、環状面２を有すると共に合成樹脂製、例えばポリアセタール樹脂製の第一の軸受体としての上ケース３と、上ケース３に当該上ケース３の軸心Ｏの回りでＲ方向に回転自在となるように重ね合わされると共に上ケース３の環状面２に対面した環状面４を有する合成樹脂製、例えばポリアセタール樹脂製の第二の軸受体としての下ケース５と、両環状面２及び４に摺動自在に接触して両環状面２及び４間に介在されている小径の弾性リング６と、径方向の内周面で弾性リング６の径方向の外周面と協働して環状の密閉空間７を形成するように、両環状面２及び４に摺動自在に接触して両環状面２及び４間に介在されていると共に弾性リング６よりも大径であって弾性リング６の径方向の外側に配された大径の弾性リング８と、環状面２と環状面４との間で弾性リング６の径方向の外周面から弾性リング８の径方向の内周面まで連続的に伸びた環状の空間の全体からなる密閉空間７に充填されたシリコーン系グリースからなる潤滑剤９とを具備している。
【００２０】
内周面１１によって規定された貫通孔１２を有する環状の上ケース３は、環状面２を有した円環状の上ケース本体部１３と、上ケース本体部１３の環状面２に一体に形成されていると共に下ケース５に向かって垂下した最内周側円筒状垂下部１４と、最内周側円筒状垂下部１４の径方向の外側に配されていると共に環状面２に一体に形成されており、しかも、下ケース５に向かって垂下した内周側円筒状垂下部１５と、上ケース本体部１３の径方向の外周縁に一体に形成された円筒状垂下係合部１６と、円筒状垂下係合部１６の径方向の内側であって内周側円筒状垂下部１５の径方向の外側に配されていると共に環状面２に一体に形成されている外周側円筒状垂下部１７と、円筒状垂下係合部１６の径方向の内周面に形成された係合フック部１８と、上ケース本体部１３の径方向の内周側において当該上ケース本体部１３の外面１９に一体に形成されている円筒部２０とを備えて、一体形成されている。
【００２１】
貫通孔１２と同心、同径であって内周面２１によって規定された貫通孔２２を有した環状の下ケース５は、環状面４を有した円環状の下ケース本体部２３と、下ケース本体部２３の径方向の内周縁に一体に形成されていると共に最内周側円筒状垂下部１４の径方向の内側に配されるように上ケース３に向かって突出した最内周側円筒状突出部２４と、最内周側円筒状突出部２４の径方向の外側に配されていると共に環状面４に一体に形成されており、しかも、最内周側円筒状垂下部１４及び内周側円筒状垂下部１５間に配されるように上ケース３に向かって突出した内周側円筒状突出部２５と、内周側円筒状突出部２５の径方向の外側に配されていると共に環状面４に一体に形成されており、しかも、内周側円筒状垂下部１５の径方向の外側に配されるように上ケース３に向かって突出した小径の環状突起２６と、下ケース本体部２３の径方向の外周縁に一体に形成されていると共に、円筒状垂下係合部１６及び外周側円筒状垂下部１７間に配されるように上ケース３に向かって突出した円筒状突出係合部２７と、円筒状突出係合部２７の径方向の内側であって環状突起２６の径方向の外側に配されていると共に環状面４に一体に形成されており、しかも、外周側円筒状垂下部１７の径方向の内側に配されるように上ケース３に向かって突出していると共に環状突起２６よりも大径の環状突起２８と、円筒状突出係合部２７の径方向の外周面に形成されていると共に、係合フック部１８に係合する係合フック部２９とを備えて、一体形成されている。
【００２２】
上ケース３は、その径方向の外周縁部の円筒状垂下係合部１６の係合フック部１８で下ケース５における径方向の外周縁部の円筒状突出係合部２７の係合フック部２９にスナップフィット式に弾性係合して下ケース５に弾性嵌着されるようになっている。
【００２３】
上ケース３及び下ケース５のその径方向の外周縁部及び内周縁部のうちの少なくとも一方、本例では両縁部において、上ケース３及び下ケース５間には、上ケース本体部１３、最内周側円筒状垂下部１４及び内周側円筒状垂下部１５と下ケース本体部２３、最内周側円筒状突出部２４、内周側円筒状突出部２５及び環状突起２６とによりラビリンス（迷路）３１が、上ケース本体部１３、円筒状垂下係合部１６及び外周側円筒状垂下部１７と下ケース本体部２３、円筒状突出係合部２７及び環状突起２８とによりラビリンス３２が夫々形成されるようになっており、斯かる内周縁部のラビリンス３１及び外周縁部のラビリンス３２により密閉空間７への外部からの塵埃、泥水等の侵入が防止されている。
【００２４】
弾性リング６は、天然ゴム、合成ゴム又は熱可塑性エラストマーからなって、その断面形状は略円形であり、弾性リング８も、天然ゴム、合成ゴム又は熱可塑性エラストマーからなって、その断面形状は略円形である。弾性リング６及び８は、環状突起２６よりも径方向の外側に配されていると共に環状突起２８よりも径方向の内側に配されており、斯かる弾性リング６及び８は、スラスト荷重下で両環状面２及び４に押されて密閉空間７の容積を小さくするように撓み変形するようになっている。
【００２５】
密閉空間７には、スラスト無荷重下で密閉空間７を隙間なしに満たす量の潤滑剤９が充填されており、斯かる量の潤滑剤９は、スラスト荷重下でも弾性リング６及び８の弾性変形によりその容積が減少された密閉空間７を隙間なしに満たす量となり、密閉空間７に隙間なしに満たされた潤滑剤９は、弾性変形する弾性リング６及び８と共にスラスト荷重を受けて弾性リング６及び８の負荷を軽減することになる。
【００２６】
以上のスラスト滑り軸受１は、図３に示すようなストラット型サスペンションアセンブリにおけるコイルばね４１の上部ばね座４２と、油圧ダンパのピストンロッド４３が固着される車体側の取付部材４４との間に装着されて用いられる。この場合、貫通孔１２及び２２にピストンロッド４３の上部が上ケース３及び下ケース５に対して軸心Ｏの回りでＲ方向に回転自在になるようにして挿通される。
【００２７】
図３に示すようにスラスト滑り軸受１を介して装着されたストラット型サスペンションアセンブリでは、ステアリング操作に際してはコイルばね４１を介する上部ばね座４２の軸心Ｏの回りでの相対的なＲ方向の回転は、上ケース３に対する下ケース５の同方向の相対的な回転で滑らかに行われる。
【００２８】
スラスト滑り軸受１によれば、弾性リング６及び８により形成された密閉空間７に潤滑剤９が充填されているために、密閉空間７に配された潤滑剤９を長期に亘って維持できる上に、密閉空間７に維持された潤滑剤９を弾性リング６及び８と両環状面２及び４との間の摺動面に弾性リング６及び８の略楕円形への弾性変形により徐々に供給できて潤滑剤９を長期に亘って摺動面に介在させることができる上に、密閉空間７に充填された潤滑剤９をスラスト荷重受けにも利用でき、而して、スラスト荷重が大きくなっても摩擦トルクはほとんど変わらず、低い摩擦トルクをもって摺動面を構成できて、長期の使用でも斯かる低い摩擦係数を維持できる上に、摺動面での摩擦音の発生がなく、しかも、ストラット型サスペンションにスラスト滑り軸受として組込んでもころがり軸受と同等の滑らかなステアリング操作を確保し得る。
【００２９】
ところで、前記のスラスト滑り軸受１では断面形状が略円形の弾性リング６及び８を用いたが、これに代えて、図４に示すように、環状面２及び４の夫々に対面する側に環状の凹み５１及び５２を有した略矩形状の弾性リング６及び８を用いてもよく、この場合、凹み５１及び５２の夫々は、弾性リング６及び８の夫々の環状面２及び４の夫々への摺動自在な接触で密閉されており、斯かる密閉された凹み５１及び５２の夫々にも、シリコーン系グリースからなる潤滑剤を隙間なしに充填するとよい。
【００３０】
図４に示すスラスト滑り軸受１では、密閉空間７に配された潤滑剤９の漏出を効果的に防ぎ得ると共に、潤滑剤９を弾性リング６及び８と両環状面２及び４との間の摺動面に凹み５１及び５２からも供給できる結果、更に長期に亘って低い摩擦トルクをもって摺動面を構成できて、長期の使用でも斯かる低い摩擦係数を維持できる。
【００３１】
なお、図４に示すスラスト滑り軸受１において凹み５１及び５２の夫々を複数個設けてもよい。
【００３２】
【発明の効果】
本発明によれば、グリース等の潤滑剤を長期に亘って摺動面に介在させることができる上に、斯かる潤滑剤をスラスト荷重受けにも利用でき、而して、スラスト荷重が大きくなっても摩擦トルクはほとんど変わらず、低い摩擦トルクをもって摺動面を構成できて、長期の使用でも斯かる低い摩擦係数を維持できる上に、摺動面での摩擦音の発生がなく、しかも、ストラット型サスペンションにスラスト滑り軸受として組込んでもころがり軸受と同等の滑らかなステアリング操作を確保し得るスラスト滑り軸受を提供することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態の好ましい一例の断面図である。
【図２】図１に示す例の下ケース及び弾性リングの平面図である。
【図３】図１に示す例をストラット型サスペンションに組込んだ例の説明図である。
【図４】本発明の実施の形態の好ましい他の例の一部の断面図である。
【符号の説明】
１スラスト滑り軸受
２、４環状面
３上ケース
５下ケース
６、８弾性リング
７密閉空間
９潤滑剤[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thrust slide bearing, and more particularly to a thrust slide bearing suitable for being incorporated as a slide bearing of a strut suspension (McPherson type) in a four-wheeled vehicle, and more particularly to a thrust slide bearing made of synthetic resin.
[0002]
[Prior art]
Generally, a strut suspension is mainly used for a front wheel of a four-wheeled vehicle, and is a combination of a coil spring and a strut assembly in which a hydraulic shock absorber is incorporated in an outer cylinder integrated with a main shaft. Such a suspension has a structure in which the axis of the coil spring is positively offset with respect to the axis of the strut to smoothly slide the piston rod of the shock absorber built in the strut, and the axis of the strut. On the other hand, there is a structure in which the axis of the coil spring is arranged to coincide. In any structure, when the strut assembly rotates together with the coil spring by a steering operation, a thrust bearing is disposed between the mounting member of the vehicle body and the upper spring seat of the coil spring so that the rotation is smoothly performed.
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-303873 [Patent Document 2]
Japanese Patent Laid-Open No. 2002-257146
[Problems to be solved by the invention]
As this thrust bearing, a rolling bearing using a ball or a needle or a synthetic resin sliding bearing is used. However, the rolling bearing has a problem that it may be difficult to maintain a smooth steering operation because the ball or needle may be damaged due to a slight swing and vibration load. Sliding bearings have higher frictional torque than rolling bearings, so when the thrust load increases, the frictional torque increases, and the steering operation becomes heavy, and depending on the combination of synthetic resins, a stick-slip phenomenon often occurs. There is a problem of generating a frictional noise caused by the stick-slip phenomenon.
[0005]
In addition, a lubricant such as grease is applied to the slide bearing. As long as such a lubricant is present on the sliding surface as desired, the frictional noise as described above hardly occurs. There may be a case where frictional noise starts to occur due to disappearance of the lubricant or the like due to the use of.
[0006]
The above-mentioned problem does not occur only in the thrust sliding bearing incorporated in the strut type suspension, and can occur in the general thrust sliding bearing as well.
[0007]
The present invention has been made in view of the above-mentioned points. The object of the present invention is to allow a lubricant such as grease to be interposed on the sliding surface over a long period of time, and to add such a lubricant to the thrust. It can also be used as a load receiver. Thus, even if the thrust load increases, the friction torque hardly changes, and the sliding surface can be configured with a low friction torque, and such a low coefficient of friction can be maintained even during long-term use. Another object of the present invention is to provide a thrust sliding bearing that does not generate frictional noise on the sliding surface and that can ensure a smooth steering operation equivalent to a rolling bearing even if it is incorporated in a strut suspension as a thrust sliding bearing.
[0008]
[Means for Solving the Problems]
The thrust slide bearing according to the first aspect of the present invention has a first bearing body having an annular surface, and the first bearing body is rotatable about the axis of the first bearing body. A second bearing body that has an annular surface that is superimposed and faces the annular surface of the first bearing body, and a small-diameter elastic ring that is slidably in contact with both annular surfaces and interposed between the annular surfaces And slidably touching both annular surfaces so as to cooperate with the small-diameter elastic ring to form an annular sealed space and being interposed between both annular surfaces and having a larger diameter than the small-diameter elastic ring In addition, a large-diameter elastic ring disposed on the outer side in the radial direction of the small-diameter elastic ring and a lubricant filled in the sealed space are provided.
[0009]
According to the thrust sliding bearing of the first aspect, since the lubricant is filled in the sealed space formed by the small-diameter and large-diameter elastic rings, the lubricant disposed in the sealed space is maintained for a long period of time. In addition, the lubricant maintained in the sealed space can be gradually supplied to the sliding surface between the elastic ring of the small and large diameters and the two annular surfaces by elastic deformation of the elastic ring, and the lubricant can be supplied over a long period of time. In addition to being able to intervene on the sliding surface, the lubricant filled in the sealed space can also be used for thrust load reception, so the friction torque hardly changes even if the thrust load increases, and the low friction torque In addition to being able to maintain such a low coefficient of friction even for long-term use, there is no generation of friction noise on the sliding surface, and even if it is incorporated as a thrust sliding bearing in a strut type suspension, the rollers It may ensure a smooth steering operation equivalent to the bearing.
[0010]
In such a thrust sliding bearing, preferably, the small-diameter and large-diameter elastic rings are bent and deformed to reduce the volume of the sealed space under a thrust load, as in the thrust sliding bearing of the second aspect of the present invention. It is like that.
[0011]
In the present invention, as in the thrust sliding bearing of the third aspect, at least lubrication in an amount that fills the sealed space with a reduced volume due to elastic deformation of the small-diameter and large-diameter elastic rings under a thrust load without a gap. However, as in the thrust sliding bearing of the fourth aspect, the lubricant may be provided in an amount that fills the sealed space without a gap under no thrust load.
[0012]
The small-diameter and large-diameter elastic rings are preferably made of natural rubber, synthetic rubber or thermoplastic elastomer as in the thrust sliding bearing of the fifth aspect of the present invention, and at least one of the small-diameter and large-diameter elastic rings. The cross-sectional shape is substantially circular as in the thrust sliding bearing of the sixth aspect of the present invention, but on the side facing each annular surface as in the thrust sliding bearing of the seventh aspect of the present invention. A substantially rectangular shape having an annular recess may be used.
[0013]
Each of the small-diameter and large-diameter elastic rings may have an annular recess on the surface facing each annular surface, like the thrust slide bearing of the eighth aspect of the present invention. The annular recesses are sealed by contact with the respective annular surfaces of the small-diameter and large-diameter elastic rings, and such a sealed slide bearing as in the thrust sliding bearing of the ninth aspect of the present invention. It is preferable that each annular recess is further filled with a lubricant.
[0014]
The lubricant contains at least one of grease and lubricating oil, like the thrust sliding bearing of the tenth aspect of the present invention, and preferably the thrust sliding bearing of the eleventh aspect of the present invention. And made of silicone grease.
[0015]
In the thrust sliding bearing of the present invention, both bearing bodies are preferably made of synthetic resin. Specifically, as in the sliding bearing of the twelfth aspect, polyacetal resin, polyamide resin, polyester resin, polyolefin The first bearing body is preferably a polyacetal resin, such as the sliding bearing of the thirteenth aspect, preferably made of a synthetic resin containing at least one of resin, polycarbonate resin and fluororesin. The second bearing body is made of a synthetic resin including at least one of polyacetal resin, polyamide resin, polyester resin, polyolefin resin, polycarbonate resin, and fluororesin. In the case of a polyester resin, a thermoplastic polyester resin is preferable.
[0016]
In the thrust slide bearing of the present invention, preferably, like the slide bearing of the fourteenth aspect, the first bearing body is connected to the second bearing body at the outer peripheral edge in the radial direction. The outer peripheral edge portion and the inner peripheral edge in the radial direction of both bearing bodies are elastically fitted to the outer peripheral edge portion in the radial direction of the two bearing bodies, as in the sliding bearing of the fifteenth aspect of the present invention. A labyrinth is formed between the bearing bodies in at least one of the parts, and the labyrinth causes dust on the sliding surface between the first bearing body and the second bearing body. Intrusion of muddy water and the like can be preferably prevented.
[0017]
In the sliding bearing of the sixteenth aspect of the present invention, the second bearing body has a pair of large-diameter and small-diameter annular protrusions integrally formed on the annular surface, and the small-diameter and large-diameter The elastic ring is disposed radially inward of the large-diameter annular protrusion of the pair of annular protrusions and is disposed radially outward of the small-diameter annular protrusion of the pair of annular protrusions. Further, both the elastic rings can be positioned in the radial direction by such a pair of annular projections, and the bending direction of the both elastic rings under a thrust load can be regulated, so that the volume of the sealed space can be effectively reduced.
[0018]
Next, the present invention and its embodiments will be described with reference to preferred examples shown in the drawings. The present invention is not limited to these examples.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2, a thrust sliding bearing 1 for use in a strut suspension in the four-wheeled vehicle of this example has an annular surface 2 and is a top bearing body made of synthetic resin, for example, polyacetal resin. A synthetic resin having a case 3 and an upper surface 3, which is superposed on the upper case 3 so as to be rotatable in the R direction around the axis O of the upper case 3 and has an annular surface 4 facing the annular surface 2 of the upper case 3. A lower case 5 as a second bearing body made of, for example, polyacetal resin, and a small-diameter elastic ring 6 interposed between the annular surfaces 2 and 4 while slidably contacting the annular surfaces 2 and 4 Both annular surfaces 2 and 4 are slidably contacted with each other so as to form an annular sealed space 7 in cooperation with the radially outer circumferential surface of the elastic ring 6 on the radially inner circumferential surface. Between 2 and 4 A large-diameter elastic ring 8 having a diameter larger than that of the elastic ring 6 and disposed on the outer side in the radial direction of the elastic ring 6, and a radial outer periphery of the elastic ring 6 between the annular surface 2 and the annular surface 4 And a lubricant 9 made of silicone grease filled in a sealed space 7 consisting of the entire annular space continuously extending from the surface to the radially inner peripheral surface of the elastic ring 8.
[0020]
An annular upper case 3 having a through hole 12 defined by the inner peripheral surface 11 is formed integrally with an annular upper case main body 13 having an annular surface 2 and an annular surface 2 of the upper case main body 13. The innermost cylindrical drooping portion 14 that hangs down toward the lower case 5 and the radially outer side of the innermost circumferential cylindrical drooping portion 14 and are formed integrally with the annular surface 2. In addition, an inner circumferential cylindrical hanging portion 15 that hangs down toward the lower case 5, a cylindrical hanging engagement portion 16 that is integrally formed on the outer peripheral edge in the radial direction of the upper case main body portion 13, and a cylinder An outer peripheral cylindrical drooping portion 17 that is disposed radially outside the inner drooping engagement portion 16 and outside the inner circumferential cylindrical drooping portion 15 and formed integrally with the annular surface 2. And an engagement hook portion formed on the radially inner peripheral surface of the cylindrical hanging engagement portion 16 8, and a cylindrical portion 20 formed integrally with the outer surface 19 of the upper case body portion 13 at the inner peripheral side of the radial direction of the upper case body 13, are integrally formed.
[0021]
An annular lower case 5 having a through hole 22 that is concentric and the same diameter as the through hole 12 and is defined by the inner peripheral surface 21 includes an annular lower case body 23 having an annular surface 4, and a lower case The innermost cylinder formed integrally with the inner peripheral edge in the radial direction of the main body 23 and projecting toward the upper case 3 so as to be arranged on the inner side in the radial direction of the innermost cylindrical hanging part 14. The cylindrical protrusion 24 and the innermost cylindrical protrusion 24 are arranged on the outer side in the radial direction and are formed integrally with the annular surface 4. An inner peripheral cylindrical protrusion 25 that protrudes toward the upper case 3 so as to be disposed between the peripheral cylindrical hanging parts 15, and a radially outer side of the inner peripheral cylindrical protrusion 25. And is formed integrally with the annular surface 4, and the radially outer side of the inner circumferential side cylindrical hanging portion 15. A small-diameter annular protrusion 26 projecting toward the upper case 3 and a radially outer peripheral edge of the lower case main body 23 so as to be disposed, and the cylindrical hanging engagement portion 16 and the outer peripheral side A cylindrical protruding engagement portion 27 protruding toward the upper case 3 so as to be disposed between the cylindrical hanging portions 17, and a radial direction of the annular protrusion 26 inside the cylindrical protruding engagement portion 27 in the radial direction. And is formed integrally with the annular surface 4, and protrudes toward the upper case 3 so as to be arranged on the radially inner side of the outer circumferential cylindrical hanging portion 17 and is annular. An annular projection 28 having a diameter larger than that of the projection 26 and an engagement hook portion 29 that is formed on the outer peripheral surface in the radial direction of the cylindrical projecting engagement portion 27 and that engages with the engagement hook portion 18 are provided. , Are integrally formed.
[0022]
The upper case 3 has an engagement hook portion 18 of the cylindrical hanging engagement portion 16 at the outer peripheral edge portion in the radial direction and an engagement hook portion of the cylindrical protrusion engagement portion 27 at the outer peripheral edge portion in the radial direction in the lower case 5. 29 is elastically engaged with the lower case 5 by snap-fitting.
[0023]
At least one of the outer peripheral edge and the inner peripheral edge in the radial direction of the upper case 3 and the lower case 5, in this example, both edges, the upper case main body 13, between the upper case 3 and the lower case 5, The labyrinth is formed by the innermost cylindrical drooping portion 14 and the inner circumferential cylindrical drooping portion 15 and the lower case main body 23, the innermost circumferential cylindrical projection 24, the inner circumferential cylindrical projection 25, and the annular projection 26. The labyrinth 32 is composed of the (maze) 31 by the upper case main body portion 13, the cylindrical hanging engagement portion 16 and the outer circumferential cylindrical hanging portion 17, the lower case main body portion 23, the cylindrical protruding engagement portion 27 and the annular protrusion 28. The labyrinth 31 at the inner peripheral edge and the labyrinth 32 at the outer peripheral edge prevent the entry of dust, muddy water, and the like from the outside into the sealed space 7.
[0024]
The elastic ring 6 is made of natural rubber, synthetic rubber or a thermoplastic elastomer, and its cross-sectional shape is substantially circular. The elastic ring 8 is also made of natural rubber, synthetic rubber or a thermoplastic elastomer, and its cross-sectional shape is substantially It is circular. The elastic rings 6 and 8 are disposed on the radially outer side than the annular protrusion 26 and are disposed on the radially inner side with respect to the annular protrusion 28. The elastic rings 6 and 8 are subjected to a thrust load. The two annular surfaces 2 and 4 are pushed and deformed so as to reduce the volume of the sealed space 7.
[0025]
The sealed space 7 is filled with an amount of lubricant 9 that fills the sealed space 7 without a gap under no thrust load, and the amount of lubricant 9 is sufficient for the elasticity of the elastic rings 6 and 8 even under a thrust load. The amount of the lubricant 9 filled in the sealed space 7 with no gap is filled with the elastic space 6 and 8 that is elastically deformed and receives a thrust load. The load of 6 and 8 will be reduced.
[0026]
The thrust sliding bearing 1 described above is mounted between the upper spring seat 42 of the coil spring 41 and the mounting member 44 on the vehicle body to which the piston rod 43 of the hydraulic damper is fixed in the strut type suspension assembly as shown in FIG. To be used. In this case, the upper part of the piston rod 43 is inserted into the through holes 12 and 22 so as to be rotatable in the R direction around the axis O with respect to the upper case 3 and the lower case 5.
[0027]
As shown in FIG. 3, in the strut type suspension assembly mounted via the thrust slide bearing 1, the relative rotation in the R direction around the axis O of the upper spring seat 42 via the coil spring 41 is performed during the steering operation. Is smoothly performed by the relative rotation of the lower case 5 with respect to the upper case 3 in the same direction.
[0028]
According to the thrust slide bearing 1, since the sealed space 7 formed by the elastic rings 6 and 8 is filled with the lubricant 9, the lubricant 9 disposed in the sealed space 7 can be maintained for a long time. In addition, the lubricant 9 maintained in the sealed space 7 is gradually supplied to the sliding surface between the elastic rings 6 and 8 and the two annular surfaces 2 and 4 by elastic deformation of the elastic rings 6 and 8 into a substantially elliptical shape. In addition, the lubricant 9 can be interposed on the sliding surface over a long period of time, and the lubricant 9 filled in the sealed space 7 can also be used as a thrust load receiver, so that the thrust load increases. However, the friction torque is almost the same, and the sliding surface can be constructed with a low friction torque, so that the low friction coefficient can be maintained even after long-term use, and there is no generation of friction noise on the sliding surface. Thrust slip on mold suspension Incorporated as received may ensure a smooth steering operation equivalent to even rolling bearings.
[0029]
By the way, the thrust sliding bearing 1 uses the elastic rings 6 and 8 having a substantially circular cross section, but instead of this, as shown in FIG. 4, the annular surfaces 2 and 4 are annular on the side facing each other. The substantially rectangular elastic rings 6 and 8 having the recesses 51 and 52 may be used, in which case the recesses 51 and 52 respectively go to the respective annular surfaces 2 and 4 of the elastic rings 6 and 8 respectively. It is preferable that each of the sealed recesses 51 and 52 is filled with a lubricant made of silicone grease without a gap.
[0030]
In the thrust sliding bearing 1 shown in FIG. 4, the lubricant 9 disposed in the sealed space 7 can be effectively prevented from leaking, and the lubricant 9 is disposed between the elastic rings 6 and 8 and the annular surfaces 2 and 4. As a result of being able to supply the sliding surface also from the recesses 51 and 52, the sliding surface can be constructed with a low friction torque for a long period of time, and such a low coefficient of friction can be maintained even in long-term use.
[0031]
A plurality of each of the recesses 51 and 52 may be provided in the thrust slide bearing 1 shown in FIG.
[0032]
【The invention's effect】
According to the present invention, a lubricant such as grease can be interposed on the sliding surface for a long period of time, and such a lubricant can also be used for a thrust load receiver, thus increasing the thrust load. However, the friction torque is almost the same, and the sliding surface can be constructed with a low friction torque, so that the low friction coefficient can be maintained even after long-term use, and there is no generation of friction noise on the sliding surface. It is possible to provide a thrust sliding bearing that can ensure a smooth steering operation equivalent to that of a rolling bearing even if it is incorporated as a thrust sliding bearing in a mold suspension.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a preferred example of an embodiment of the present invention.
FIG. 2 is a plan view of a lower case and an elastic ring in the example shown in FIG.
FIG. 3 is an explanatory diagram of an example in which the example shown in FIG. 1 is incorporated in a strut suspension.
FIG. 4 is a partial cross-sectional view of another preferred example of an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Thrust slide bearing 2, 4 Annular surface 3 Upper case 5 Lower case 6, 8 Elastic ring 7 Sealed space 9 Lubricant

Claims

A first bearing body having an annular surface, and the first bearing body so as to be rotatable about the axis of the first bearing body, and overlaid on the annular surface of the first bearing body A second bearing body having annular surfaces facing each other, a small-diameter elastic ring slidably contacting both annular surfaces and interposed between both annular surfaces, and a small-diameter elastic ring on the radially inner peripheral surface In order to form an annular sealed space in cooperation with the radially outer circumferential surface of the ring, the annular surface is slidably in contact with each other and is interposed between the annular surfaces and has a larger diameter than the small-diameter elastic ring. The diameter of the small-diameter elastic ring between the large-diameter elastic ring arranged radially outside the small-diameter elastic ring and the annular surface of the first bearing body and the annular surface of the second bearing body The sealed space comprising the entire annular space continuously extending from the outer peripheral surface in the direction to the inner peripheral surface in the radial direction of the large-diameter elastic ring The small and large diameter elastic rings are bent and elastically deformed to reduce the volume of the sealed space under a thrust load. And a lubricant that fills the sealed space without any gaps, with the volume reduced by elastic deformation of the elastic rings having a small diameter and a large diameter under a thrust load. Is a thrust slide bearing that is adapted to receive a thrust load together with a small-diameter and large-diameter elastic ring that elastically deforms under a thrust load.

The thrust sliding bearing according to claim 1, further comprising an amount of lubricant that fills the sealed space without a gap under no thrust.

The thrust sliding bearing according to claim 1 or 2, wherein the small-diameter and large-diameter elastic rings are made of natural rubber, synthetic rubber or thermoplastic elastomer.

4. The thrust slide bearing according to claim 1, wherein a cross-sectional shape of at least one of the small diameter and large diameter elastic rings is substantially circular.

The thrust sliding bearing according to any one of claims 1 to 3, wherein a cross-sectional shape of at least one of the small-diameter and large-diameter elastic rings is a substantially rectangular shape having an annular recess on a side facing each annular surface.

Each of the small-diameter and large-diameter elastic rings has an annular recess on the surface facing each annular surface, and each annular recess is in contact with each annular surface of the small-diameter and large-diameter elastic ring. The thrust slide bearing according to any one of claims 1 to 5, wherein the thrust slide bearing is hermetically sealed.

The thrust sliding bearing according to claim 6, further comprising a lubricant filled in a sealed annular recess.

The thrust sliding bearing according to any one of claims 1 to 7, wherein the lubricant includes at least one of grease and lubricating oil.

The thrust sliding bearing according to any one of claims 1 to 8, wherein the lubricant is made of silicone grease.

The thrust according to any one of claims 1 to 9, wherein the two bearing bodies are made of a synthetic resin including at least one of polyacetal resin, polyamide resin, polyester resin, polyolefin resin, polycarbonate resin, and fluororesin. Plain bearing.

The first bearing body is made of polyacetal resin, and the second bearing body is made of synthetic resin containing at least one of polyacetal resin, polyamide resin, polyester resin, polyolefin resin, polycarbonate resin, and fluororesin. The thrust slide bearing according to any one of claims 1 to 10.

The first bearing body is elastically fitted to the second bearing body at the outer peripheral edge in the radial direction at the outer peripheral edge in the radial direction of the second bearing body. The thrust slide bearing according to any one of the above.

The labyrinth is formed between both bearing bodies in at least one of the outer peripheral edge part and the inner peripheral edge part in the radial direction of the both bearing bodies, according to any one of claims 1 to 12. Thrust sliding bearing.

The second bearing body has a pair of large-diameter and small-diameter annular protrusions integrally formed on the annular surface, and the small-diameter and large-diameter elastic ring is a large-diameter of the pair of annular protrusions. The annular projections according to any one of claims 1 to 13, wherein the annular projections are arranged on the inner side in the radial direction and are arranged on the outer side in the radial direction with respect to the small-diameter annular projection of the pair of annular projections. Thrust sliding bearing.